Empagliflozin Improves Cardiac Function in Rats with Chronic Heart Failure

Empagliflozin Improves Cardiac Function in Rats with Chronic Heart Failure | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Empagliflozin Improves Cardiac Function in Rats with Chronic Heart Failure Zhenzhen Wang, Qian Liu, Xiaofang Wang, Pengpeng Wang, Zhuwen Wang, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3107228/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 11 Aug, 2023 Read the published version in Naunyn-Schmiedeberg's Archives of Pharmacology → Version 1 posted 7 You are reading this latest preprint version Abstract Objective To examine the effect of empagliflozin on cardiac function in rats with chronic heart failure and the possible mechanism. Methods Forty 6-week-old male SD rats were randomly divided into the control group, empagliflozin treatment group, and sham-operated group. SD rats in the control group and empagliflozin treatment group were subjected to ligation of the anterior descending coronary artery to induce an acute myocardial infarction model. SD rats in the sham-operated group were only subjected to threading of the anterior descending branch of the coronary artery without ligation. On the second day after surgery, the control group and sham operation group were given physiological saline by gavage, while the empagliflozin treatment group was given empagliflozin (30 mg/kg/day) by gavage. Sixteen weeks later, cardiac function, intracellular reactive oxygen species (ROS) levels, mitochondrial membrane potential (MMP), serum brain natriuretic peptide, hypersensitive C-reactive protein (hs-CRP), iNOS expression levels and myocardial morphological changes were observed. Results Compared with that in the control group, heart function in the empagliflozin treated group was significantly improved, MMP was increased, intracellular ROS levels were decreased, and NT -proBNP and hs-CRP were significantly reduced, and HE staining showed that the cell oedema was less than that in the control group, tissue arrangement was more orderly, and iNOS expression was inhibited. Conclusion Empagliflozin can improve cardiac function in rats with chronic heart failure, and the mechanism may involve inhibiting inflammation, reducing myocardial oxidative stress, and improving myocardial fibrosis. Chronic heart failure Empagliflozin Reactive oxygen species Hypersensitive C-reactive protein Membrane potential Figures Figure 1 Figure 2 Figure 3 Introduction With the ageing of the population in China and the increasing incidence of cardiovascular diseases (CVDs) such as coronary heart disease, atrial fibrillation, and hypertension, the number of patients with heart failure (HF) is increasing yearly. Chronic heart failure (CHF) is the final stage of various heart diseases and the final stage for CVD prevention and control. It is estimated that the current number of CVD patients is 290 million [1] . At present, there are over 13.7 million HF patients (with a prevalence rate of 1.3%) in China [2] , resulting in a huge burden on the social and economic health of the country. HF has a high incidence rate and mortality. The one-year mortality of CHF patients is 7.2%, and the one-year hospitalization rate is 31.9%, while the mortality and hospitalization rates of acute HF patients are as high as 17.4% and 43.9%, respectively [3] . Although significant breakthroughs have been made in the treatment of HF in the past decade, the incidence rate and mortality of HF patients are still high [4-5] . Currently, the treatment of HF remains a major challenge in cardiology. Diabetes is an independent risk factor for HF. Every 1% increase in glycosylated haemoglobin can increase the incidence rate of HF from 8% to 36%. In recent years, the novel hypoglycaemic drug sodium glucose cotransporter 2 inhibitor (SGLT-2i) has shown significant cardiovascular benefits, and SGLT-2i has been included in the 2021 European Society of Cardiology (ESC) Guidelines for the Diagnosis and Treatment of Acute and Chronic Heart Failure. The pathogenesis of HF is relatively complex. At present, treatment of HF has shifted from traditional cardiac strengthening, diuresis, and vasodilation by targeting the body's haemodynamics to treatment based on neurohumoural mechanisms. Treatment options mainly include renin angiotensin aldosterone system (RAAS) inhibitors, β receptor blockers, aldosterone receptor antagonists, positive inotropic drugs, and diuretics [6] ; Previous studies have shown that dapagliflozin reduces blood volume, increases haematocrit, and enhances the oxygen carrying capacity of the body [7-9] . The DAPA-HF test and the latest EMPEROR Reduced test showed that SGLT-2 inhibitors could reduce the risk of cardiovascular death or the composite event endpoint of hospitalization due to HF in patients with HF with reduced ejection fraction (EF%), whether these patients had diabetes or not [10] . In addition, CANTOS research has shown that inflammation is an important cardiovascular risk factor, and anti-inflammatory treatment can improve the prognosis of CVDs [11] . However, the mechanism by which empagliflozin can treat CHF is not clear. Thus, we established a CHF rat model by ligating the anterior descending branch of the coronary artery in SD rats to study the effect of empagliflozin on heart function during CHF and the possible mechanisms. 1 Materials and Methods 1.1 Groupings and processing The animal experiment was carried out in strict accordance with the "Regulations on the Management of Experimental Animals" issued by the State Council of the People's Republic of China. This experiment was approved by the Experimental Animal Ethics Committee of the Second Affiliated Hospital of Chongqing Medical University. Male SD rats were provided by Chongqing Medical University and were randomly divided into a control group of 15 rats (AMI + NS), an empagliflozin-treated group of 14 rats (AMI + empagliflozin), and a sham-operated group of 11 rats (sham-operated + NS). The ischaemic HF model was established as previously described [ 12 ] by ligating the left anterior descending artery in the control group and the empagliflozin-treated group. The sham-operated group were only subjected to threading without ligation at the same site. Postoperative intraperitoneal injection of penicillin (4000 U/d * 3 days) was performed to prevent infection. On the second day after surgery, the control group and sham operation group were given physiological saline by gavage, while the treatment group was given empagliflozin (30 mg/kg/day) by gavage for a total of 16 weeks. Empagliflozin (10 mg/tablet) was purchased from Shanghai Bollinger Ingerhan Pharmaceutical Co., Ltd. The rat hypersensitive C-reactive protein (hs-CRP) enzyme-linked immunosorbent assay (ELISA) kit was purchased from Shenzhen Zike Biotechnology Co., Ltd. The IP lysis buffer was obtained from Shanghai Biyuntian Biotechnology Co., Ltd., and the N-terminal pro-B-type natriuretic peptide (NT-proBNP) ELISA kit for rats was purchased from Shanghai Xitang Biotechnology Co., Ltd. iNOS antibodies (Beijing Boorsen Biotechnology Co., Ltd. ), the HX-200 animal ventilator (Chengdu Taimeng Technology Co., Ltd. ), and the Vivid Doppler ultrasound instrument (probe frequency 10 MHz, GE company) were used. 1.2 Echocardiographic detection of cardiac function and specimen collection After 16 weeks of gavage, SD rats were intraperitoneally anaesthetized with chloral hydrate, placed on their backs, and fixed on the operating table. The cardiac function of each group of rats was measured by ultrasound. The long axis of the left ventricle was displayed on a two-dimensional ultrasound section, and M-ultrasound was used to measure the left ventricular end diastolic diameter (LVIDd), left ventricular internal diameter (LVIDs), and EF%. After the cardiac function testing, blood was collected from the inferior vena cava, the rats were decapitated, and the heart was removed by thoracotomy. The tissues were washed with physiological saline, and vascular tissue, the atrium, the right ventricle, and fibrotic areas were removed after left ventricular infarction. The remaining noninfarcted myocardium of the left ventricle was prepared into paraffin sections, and the remaining portion was stored in liquid nitrogen for later use. Blood was collected at 950 days, centrifuged for 20 minutes to extract the supernatant, and stored at -20 ℃ for future use. 1.3 Intracellular reactive oxygen species (ROS) levels and mitochondrial membrane potential (MMP) were measured by flow cytometry Twenty milligrams of noninfarcted left ventricular myocardial tissue was cut into 1–2 mm fragments with ophthalmic scissors, 2 ml of 0.25% trypsin was added, and the tissue was digested in a 37°C water bath for 3 minutes, centrifuged at 500 r for 1 minute. Then, 1 ml of foetal bovine serum was added to terminate the digestion. The differential adhesion method was used to separate myocardial cells, and a cell counting plate was used to count the number of myocardial cells. Each group contained 1.0 × 10 6 resuspended cells suspended in DCFH-DA diluted 1:1000 with serum-free culture medium. A total of 1.0 × 10 6 resuspended cells were added to 0.5 ml of Rh123 staining solution, and ROS levels and the MMP were detected by flow cytometry. 1.4 ELISA analysis of blood BNP levels The preserved SD rat plasma was tested according to the instructions of the rat BNP kit. 1.5 ELISA analysis of blood hs-CRP levels The preserved SD rat plasma was diluted appropriately and analysed according to the kit instructions. The absorbance value was measured using ELISA at a wavelength of 450 nm, and a standard curve was drawn using the standard sample provided by the kit. Serum levels of hs-CRP in each group were calculated, and each sample was examined 3 times. 1.6 HE staining and immunohistochemical analysis of iNOS expression Rat myocardial tissue was fixed with 4% paraformaldehyde for 24 hours and embedded in paraffin (5 µm) for HE staining. The immunohistochemical steps were carried out according to the kit instructions (Beijing Zhongshan Jinqiao Company). The paraffin sections were dewaxed with xylene and rehydrated through a gradient, and antigen repair was performed with citric acid solution. Goat serum sealing was performed at room temperature for 1 hour, and diluted rabbit-derived iNOS polyclonal antibodies (1:250) were added dropwise. The samples were incubated overnight at 4°C. Goat anti-rabbit secondary antibodies were added the next day. The horseradish enzyme-labelled albumin working solution (S-A/HRP) was incubated at room temperature for 30 minutes, followed by DAB staining and haematoxylin staining. The film was sealed, and myocardial morphology and iNOS expression were observed under a microscope. The integrated optical density (IOD) of iNOS-positive myocardial cells in each group was measured using Image-Pro Plus (IPP) software to determine the relative protein expression of iNOS. 1.7 Statistical analysis The experimental data were analysed with SPSS 21.0 statistical software, and the experimental results were subjected to a normal distribution. Indicators with a normal distribution and homogeneity of variance between groups were compared by ANOVA; otherwise, the rank sum test was used. The difference was statistically significant at P < 0.05. 2 Results 2.1 Feeding situation Eight SD rats in the model group died, and one rat in the sham surgery group died. The causes of death were infection, acute left HF, and malignant arrhythmia. The remaining 31 SD rats reached the experimental endpoint. 2.2 Cardiac function test results At 16 weeks after ligation of the left anterior descending artery, the control group showed a significant increase in LVIDd and LVIDs (P < 0.05) compared with the sham-operated group, while LVEF decreased significantly (P < 0.05). Compared with the control group, the empagliflozin treatment group showed a significant reduction in LVIDd and LVIDs (P < 0.05) and a significant increase in LVEF (P < 0.05), as shown in Table 1 and Fig. 1 . Table I. Echocardiographic Parameters of Rats with HF Following MI (χ ± s) Sham group control group Empagliflozin group 4 weeks following MI LVIDd (cm) 0.55 ± 0.04 0.69 ± 0.11 a 0.64 ± 0.04 b LVIDs (cm) 0.26 ± 0.09 0.55 ± 0.11 a 0.47 ± 0.11 b LVEF (%) 90.9 ± 2.74 73.3 ± 8.21 a 76.9 ± 3.79 b 16 weeks following MI LVIDd (cm) 0.52 ± 0.03 0.73 ± 0.09 a 0.57 ± 0.04 b LVIDs (cm) 0.21 ± 0.04 0.5 ± 0.11 a 0.28 ± 0.06 b LVEF (%) 92.5 ± 3.03 70.5 ± 9.54 a 85.1 ± 6.37 b a P<0.05, compared with the sham group; b P<0.05, compared with the control group. 2.3 Myocardial ROS and MMP Compared with the sham surgery group (107.14 ± 4.79), the control group (196.85 ± 12.25) and empagliflozin-treated group (133.16 ± 12.25) showed significant increases in intracellular ROS in myocardial cells (P < 0.05). The empagliflozin treatment group showed a significant decrease compared to the control group (P < 0.05). Compared with that in the sham operation group (104.73 ± 4.31), the MMP in the control group (32.76 ± 7.7) and empagliflozin treatment group (80.21 ± 14.98) decreased. The empagliflozin treatment group showed an increase compared to the control group, as shown in Fig. 2. 2.4 Serum BNP levels Compared to those in the sham surgery group (8.76 ± 0.46 µg/L), serum BNP levels were significantly increased in the control group (22.7 ± 1.23 µg/L) and empagliflozin treatment group (13.5 ± 0.59 µg/L) (P < 0.05). The empagliflozin treatment group showed a significant decrease compared to the control group (P < 0.05). 2.5 Serum levels of hs-CRP Compared to those in the sham surgery group (10.1 ± 0.37 µg/L), serum BNP levels were significantly increased in the control group (29.4 ± 1.02 µg/L) empagliflozin treatment group (14.3 ± 0.53 µg/L) (P < 0.05). The empagliflozin treatment group showed a significant decrease compared to the control group (P < 0.05). 2.6 HE staining and iNOS expression in the myocardium of rats in each group HE staining showed that in the sham surgery group [percentage of oedematous cells among total cells: (12 ± 0.13)%], the myocardial fibres were arranged neatly, the cytoplasm was rich and uniform, and the nucleus was intact. The control group showed significant myocardial tissue oedema compared to the sham surgery group [percentage: (79 ± 0.53)%] (P < 0.05), and the myocardial fibres were broken and disordered, there was nuclear disappearance, and a large amount of fibrous tissue formed around the infarcted area. Compared with that in the control group, myocardial tissue oedema in the empagliflozin treatment group was significantly reduced [percentage: (31 ± 0.29)%] (P < 0.05). The arrangement was relatively neat, the nucleus was relatively intact, and fibrosis around the infarction was reduced, as shown in Fig. 3 . The expression level of iNOS [IOD (15.67 ± 2.41)] in the sham operation group was very low, while the expression level of iNOS in the control group [IOD (1254 ± 23.18)] and empagliflozin treatment group [IOD 109.83 ± 15.09)] was significantly higher than that in the sham operation group (P < 0.05); the expression level of iNOS in the empagliflozin treatment group was significantly lower than that in the control group (P < 0.05), as shown in Fig. 3 . 3 Discussion In this study, it was found that empagliflozin had anti-inflammatory effects, reduced myocardial oxidative stress, stabilized cell membrane potential, and inhibited myocardial fibrosis, thereby improving heart function in rats with HF. Empagliflozin is a novel oral hypoglycaemic drug that is a SGLT-2i. Previous studies have shown that SGLT-2i can significantly reduce the risk of cardiovascular death and hospitalization rate for HF, but the mechanism of action is still not fully understood. Research has shown that oxidative stress is present in almost all forms of CVD and plays a crucial role in energy regulation within myocardial cells. Oxidative stress is defined as a state in which cells and/or the body produce excessive ROS that exceed endogenous antioxidant defence capabilities, thereby damaging proteins, lipids, and DNA. Active oxygen includes superoxide (O-2 ·), hypochlorite (HOCl) and hydrogen peroxide (H2O2). Under normal physiological conditions, the generation of ROS in the heart is minimal, and there is an antioxidant defence system that clears ROS to maintain metabolic balance. However, in response to certain harmful stimuli, cardiac oxidative antioxidant homeostasis is disrupted, and the accumulated O-2 · is highly diffused and damages myocardial cells [ 13 – 14 ] . In addition, ROS can reduce myocardial cell contraction in a concentration-dependent manner [ 15 – 16 ] , leading to a certain degree of cardiac dysfunction [ 17 – 18 ] . This study showed a significant increase in myocardial ROS levels in rats with CHF, confirming that CHF rats were in a state of oxidative stress at this time, while myocardial ROS levels in rats treated with empagliflozin were significantly lower than those in the control group. Oxidative stress plays an important role in the occurrence and development of HF; it can mediate cell proliferation, myocardial remodelling, and myocardial apoptosis by activating various signalling pathways, thereby causing further deterioration of cardiac function. Moreover, the role of mitochondrial dysfunction in CVDs has been fully confirmed. A decrease in the MMP is a sign of early apoptosis. This study showed that the MMP of CHF rats was lower than that of sham rats, the MMP of CHF rats was higher than that of control rats after treatment with empagliflozin, and intracellular ROS levels were lower than those in the control group. These results suggested that empagliflozin could stabilize MMP, improve mitochondrial function and increase left ventricular EF% in rats with HF by reducing myocardial ROS production. Empagliflozin can reduce myocardial cell apoptosis and improve cardiac function in HF rats. These results are consistent with previous studies showing that empagliflozin reduces oxidative stress and improves cardiac function [ 19 – 20 ] . Inflammation is an important factor in the severity of CHF. The increase in proinflammatory biomarkers in patients with HF is related to disease severity. Inflammatory cytokines not only lead to endothelial dysfunction but also increase the development of myocardial fibrosis [ 21 ] . Previous studies have shown that inflammation plays a crucial role in ischaemic myocardial damage, leading to the deterioration of cardiac structure and function, thereby promoting structural changes and functional decline in ischaemic heart disease [ 22 ] . Inflammatory reactions are present during the entire occurrence and development of HF in patients. hs-CRP, which is a biomarker of inflammation, was significantly elevated in the serum of CHF rats compared to sham-operated rats. The serum levels of hs-CRP in the empagliflozin-treated group were decreased compared to those in the control group, indicating that empagliflozin has anti-inflammatory effects. Furthermore, this study showed that myocardial fibres in HF rats were disrupted and arranged in a disordered manner, which was accompanied by the disappearance of cell nuclei and the formation of a large amount of fibrous tissue around the infarcted area. After treatment with empagliflozin, myocardial cell tissue oedema in HF rats was significantly reduced, and fibrosis around the infarcted area was reduced, indicating that empagliflozin could inhibit myocardial fibrosis. In addition, studies have shown a significant increase in iNOS levels in the myocardial cells of patients with HF [ 23 – 24 ] . INOS can catalyse the synthesis of excess NO from L-arginine, which in turn reacts with O2 to form the strong oxidant peroxynitrite ion (ONOO-), which can cause tissue damage and participate in the development of CHF [ 25 ] . The results of this study showed a significant increase in iNOS levels in the myocardial tissue of HF rats compared to sham-operated rats, which is consistent with the significant increase in iNOS levels in the myocardium of HF patients reported by Umar [ 23 ] . However, iNOS levels in the myocardial tissue of HF rats was significantly decreased after treatment with empagliflozin. This finding suggests that empagliflozin can alleviate oxidative stress in CHF rats by downregulating iNOS expression, thereby improving cardiac function in CHF rats. In summary, empagliflozin ameliorated cardiovascular risk factors and played a role in cardiovascular protection by exerting anti-inflammatory effects, reducing oxidative stress, stabilizing cell membrane potential, inhibiting myocardial fibrosis, increasing the EF% and other mechanisms. However, its mechanism of action is still not fully understood. We believe that with further research, the mechanism by which empagliflozin affects CHF will be revealed, providing new therapeutic targets for CHF. Conclusion This study demonstrated that empagliflozin improves cardiac function in the context of CHF. Its mechanism may be related to inhibiting inflammation, reducing myocardial oxidative stress, and improving myocardial fibrosis. Declarations Declarations Ethical Approval The animal experiment was carried out in strict accordance with the "Regulations on the Management of Experimental Animals" issued by the State Council of the People's Republic of China. This experiment was approved by the Experimental Animal Ethics Committee of the Second Affiliated Hospital of Chongqing Medical University. Competing interests The authors have no relevant financial or non-financial interests to disclose. Funding This work was supported by Shandong Province Medical and Health Technology Development Plan Project. Author contribution All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Zhenzhen Wang, QianLiu, Xiaofang Wang, Pengpeng Wang,Fenglei Zhang and Zhuwen Wang. The first draft of the manuscript was written by Zhenzhen Wang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Data availability All source data for this study are available upon reasonable request from the authors. References HU S T, GAO R L, LIU L S, et al.Summary of the 2018 Report on Cardiovascular Diseases in China.Chinese Circulation Journal, 2019,34:209–220. HaoG, WangX, ChenZ, et al. Prevalence of heart failure and left ventricular dysfunction in China: the China Hypertension Survey, 2012–2015. Eur J Heart Fail, 2019, 21:1329–1337. MURPHY S P,IBRAHIM N E,JANUZZI J L.Heart failure with reduced ejection fraction: a review.JAMA,2020,324:488–504. SIMPSON J,JHUND P S,LUND L H,et al.Prognostic models derived in PARADIGM-HF and validated in AT-MOSPHERE and the Swedish Heart Failure Registry to predict mortality and morbidity in chronic heart failure.JAMA Cardiol,2020,5:432–441. UCHMANOWICZ I,LEE C S,VITALE C,et,al.Frailty and the risk of all-cause mortality and hospitalization in chronic heart failure:a meta-analysis.ESC Heart Fail,2020,7:3427–3437. Packer M, Anker SD, Butler J, et al. Cardiovascular and renal outcomes with empagliflozin in heart failure. N Engl J Med, 2020, 383: 1413–1424. Testani JM, Chen J, McCauley BD, Kimmel SE, Shannon RP. Potential effects of aggressive decongestion during the treatment of decompensated heart failure on renal function and survival. Circulation 2010;122:265–72. Kataoka H. Biochemical determinants of changes in plasma volume after decongestion therapy for worsening heart failure. J Card Fail 2019;25:213–7. Ohara K, Masuda T, Murakami T, et al. Effects of the sodium-glucose cotransporter 2 inhibitor dapagliflflozin on flfluid distribution: a comparison study with furosemide and tolvaptan. Nephrology (Carlton) 2019;24:904–11. Zannad F, Ferreira JP, Pocock SJ, et al.SGLT2 inhibitors in patients with heart failure with reduced ejection fraction:a meta-analysis of the EMPEROR-Reduced and DAPA-HF trials.Lancet,2020,396:819–829. Ridker PM, Everett BM, Thuren T, et al.Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease.N Engl J Med,2017,377:1119–1131. Wu H, Zhu Q, Cai M,et al.Effect of Inhibiting Malonyl-CoA Decarboxylase on Cardiac Remodeling after Myocardial Infarction in Rats.Cardiology. 2014,127:236–244. HalliwellB. Reactive species and antioxidants. Redox biology is a fundamental theme of aerobic life. Plant Physiol, 2006,141:312–322. Palmieri V, Innocenti F, Guzzo A, et al.Left ventricular systolic longitudinal function as predictor of outcome in patients with sepsis.Circ Cardiovasc Imaging,2015,8:e003865. KwonSH, PimentelDR, RemondinoA, et al. H(2)O༈2༉regulates cardiac myocyte phenotype via concentration-dependent activation of distinct kinase pathways. J Mol Cell Cardiol, 2003,35:615–621. SabriA, ByronKL, SamarelAM, et al. Hydrogen peroxide activates mitogen-activated protein kinases and Na+-H + exchange in neonatal rat cardiac myocytes. Circ Res, 1998,82:1053–1062. Wu Y,Yao YM,Lu ZQ.Mitochondrial quality control mechanisms as potential therapeutic targets in sepsis-induced multiple organ failure. J Mol Med(Berl).2019,97:451–462. CantonM, NeverovaI, MenaboR, et al. Evidence of myofibrillar protein oxidation induced by postischemic reperfusion in isolated rat hearts. Am J Physiol Heart Circ Physiol, 2004,286:H870-H877. Lee TM,Chang NC,Lin SZ.Dapagliflozin, a selective SGLT2 inhibbitor, attenuated cardiac fibrosis by regulating the macrophage polarization via STAT3 signaling in infarcted rat hearts. Free Radic Biol Med,2017,104:298–310. Tanajak p, Sa-Nguanmoo P,Sivasinprasasn S, et al.Cardioprotection of dapagliflozin and vildagliptin in rats with cardiac ischemia-reperfusion injury. J Endocrinol,2018,236:69–84. Briasoulis A,Androulakis E,Christophides T,et al.The role of inflmmation and cell death in the pathogenesis,progression and treatment of heart failure.Heart Fail Rev,2016,21:169–176. WilhelmiMH, LeyhRG, WilhelmiM, et al.Upregulation of endothelial adhesion molecules in hearts with congestive and ischemic cardiomyopathy: immunohistochemical evaluation of inflammatory endothelial cell activation.Eur J Cardiothorac Surg, 2005, 27:122–127. Umar S, van der Laarse A.Nitric oxide and nitric oxide synthase isoforms in the normal, hypertrophic, and failing heart.Mol Cell Biochem. 2010,333:191–201. Li W, Olshansky B.Inflammatory cytokines and nitric oxide in heart failure and potential modulation by vagus nerve stimulation.Heart Fail Rev. 2011,16:137–45. Giordano FJ.Oxygen, oxidative stress, hypoxia, and heart failure.J Clin Invest. 2005,115:500–8. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 11 Aug, 2023 Read the published version in Naunyn-Schmiedeberg's Archives of Pharmacology → Version 1 posted Editorial decision: Major revision 05 Jul, 2023 Reviews received at journal 04 Jul, 2023 Reviewers agreed at journal 28 Jun, 2023 Reviewers invited by journal 28 Jun, 2023 Editor assigned by journal 27 Jun, 2023 Submission checks completed at journal 27 Jun, 2023 First submitted to journal 25 Jun, 2023 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3107228","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":213802760,"identity":"3c951868-f05d-4e0f-bfd6-377ccd04a57e","order_by":0,"name":"Zhenzhen Wang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYBACgwNgSkKOX/7wgQMffhCvxcZYcgZb4sGZPcRrSUvccIPH+DAHGzFajp89/PLHn8OJDbd7Phxm4GGQ5xc7gF+L2Zm8NAsJnsPGjXPObjhcYMFgOHN2AgEtB3LMDAwkDss2M+RuODyDhyHB4DYhLeffmBkkGBxmbGPIeXCYh40ILfY3cowfHEhIU+yRyGEgTovljTdmjA0HbIwleI4ZAANZgrBfDM7nGH/88UdCzv548+MPH37YyPNLE9ACBGwSSBwJnMqQAfMHopSNglEwCkbByAUAYxxO57KxwV8AAAAASUVORK5CYII=","orcid":"","institution":"Department of Cardiology, People’s Hospital of Dongying, No. 317, Dong Cheng Nan Yi Road, Dongying, Shandong Province, China","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Zhenzhen","middleName":"","lastName":"Wang","suffix":""},{"id":213802761,"identity":"594ffce6-14d1-4e91-9912-a025b94e44ed","order_by":1,"name":"Qian Liu","email":"","orcid":"","institution":"Department of Cardiology, People’s Hospital of Dongying, No. 317, Dong Cheng Nan Yi Road, Dongying, Shandong Province, China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Qian","middleName":"","lastName":"Liu","suffix":""},{"id":213802762,"identity":"fcf19142-ac50-45ee-b369-5d5a6bbf50cc","order_by":2,"name":"Xiaofang Wang","email":"","orcid":"","institution":"Department of Cardiology, People’s Hospital of Dongying, No. 317, Dong Cheng Nan Yi Road, Dongying, Shandong Province, China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xiaofang","middleName":"","lastName":"Wang","suffix":""},{"id":213802763,"identity":"232645d0-42a3-4a54-aa69-6cad6c0fccc5","order_by":3,"name":"Pengpeng Wang","email":"","orcid":"","institution":"Dezhou Municipal Hospital of Shandong Province, China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Pengpeng","middleName":"","lastName":"Wang","suffix":""},{"id":213802764,"identity":"232b802d-b031-4f99-a1cb-9c464fdfbe34","order_by":4,"name":"Zhuwen Wang","email":"","orcid":"","institution":"Department of Cardiology, People’s Hospital of Dongying, No. 317, Dong Cheng Nan Yi Road, Dongying, Shandong Province, China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zhuwen","middleName":"","lastName":"Wang","suffix":""},{"id":213802765,"identity":"2d232b8d-1338-418d-8dda-803c49be57c3","order_by":5,"name":"Fenglei Zhang","email":"","orcid":"","institution":"Department of Cardiology, People’s Hospital of Dongying, No. 317, Dong Cheng Nan Yi Road, Dongying, Shandong Province, China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Fenglei","middleName":"","lastName":"Zhang","suffix":""}],"badges":[],"createdAt":"2023-06-25 14:29:21","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3107228/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3107228/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00210-023-02655-7","type":"published","date":"2023-08-11T21:57:17+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":39381133,"identity":"896c36ae-7481-45db-8128-a7f5c7683a2d","added_by":"auto","created_at":"2023-06-30 17:13:04","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":324884,"visible":true,"origin":"","legend":"\u003cp\u003eEchocardiographic measurements of the rats in the different groups (16 weeks).\u003c/p\u003e\n\u003cp\u003eA: Normal cardiac function in the sham group. B: Diminished cardiac function in the AMI group. C: Improved cardiac function in the empagliflozin group compared with the AMI group.\u003c/p\u003e","description":"","filename":"FIG1.png","url":"https://assets-eu.researchsquare.com/files/rs-3107228/v1/4d0113f3b5c79b0bf9656d33.png"},{"id":39381134,"identity":"86e95760-d56b-4ca2-896f-1162b337ac3e","added_by":"auto","created_at":"2023-06-30 17:13:05","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":266046,"visible":true,"origin":"","legend":"\u003cp\u003eA1. sham surgery group. B1. Control group. C1. Empagliflozin treatment group.\u003c/p\u003e\n\u003cp\u003eROS levels and MMP level in the myocardial cells of rats in each group\u003c/p\u003e","description":"","filename":"FIG2.png","url":"https://assets-eu.researchsquare.com/files/rs-3107228/v1/b44d6a28092072ca2c630ac9.png"},{"id":39381135,"identity":"863b3e1b-50ba-4ca6-a25b-fb05aec4386d","added_by":"auto","created_at":"2023-06-30 17:13:05","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":2375513,"visible":true,"origin":"","legend":"\u003cp\u003eMyocardial samples of the area surrounding of the infarction, as visualized by HE staining (HE × 400) and IHC staining (× 400).\u003c/p\u003e","description":"","filename":"FIG3.png","url":"https://assets-eu.researchsquare.com/files/rs-3107228/v1/cec4a3f53008a0e2d737f60d.png"},{"id":44737057,"identity":"338d55e3-00dc-4434-8fa7-5d7cd0ad60d0","added_by":"auto","created_at":"2023-10-16 22:32:54","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2537723,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3107228/v1/ef921ea8-05b1-4a7a-a008-fe516085810c.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Empagliflozin Improves Cardiac Function in Rats with Chronic Heart Failure","fulltext":[{"header":"Introduction","content":"\u003cp\u003eWith the ageing of the population in China and the increasing incidence of cardiovascular diseases (CVDs) such as coronary heart disease, atrial fibrillation, and hypertension, the number of patients with heart failure (HF) is increasing yearly. Chronic heart failure (CHF) is the final stage of various heart diseases and the final stage for CVD prevention and control. It is estimated that the current number of CVD patients is 290 million \u003csup\u003e[1]\u003c/sup\u003e. At present, there are over 13.7 million HF patients (with a prevalence rate of 1.3%) in China\u003csup\u003e[2]\u003c/sup\u003e, resulting in a huge burden on the social and economic health of the country. HF has a high incidence rate and mortality. The one-year mortality of CHF patients is 7.2%, and the one-year hospitalization rate is 31.9%, while the mortality and hospitalization rates of acute HF patients are as high as 17.4% and 43.9%, respectively\u003csup\u003e[3]\u003c/sup\u003e. Although significant breakthroughs have been made in the treatment of HF in the past decade, the incidence rate and mortality of HF patients are still high\u003csup\u003e[4-5]\u003c/sup\u003e. Currently, the treatment of HF remains a major challenge in cardiology.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp;Diabetes is an independent risk factor for HF. Every 1% increase in glycosylated haemoglobin can increase the incidence rate of HF from 8% to 36%. In recent years, the novel hypoglycaemic drug sodium glucose cotransporter 2 inhibitor (SGLT-2i) has shown significant cardiovascular benefits, and SGLT-2i has been included in the 2021 European Society of Cardiology (ESC) Guidelines for the Diagnosis and Treatment of Acute and Chronic Heart Failure. The pathogenesis of HF is relatively complex. At present, treatment of HF has shifted from traditional cardiac strengthening, diuresis, and vasodilation by targeting the body\u0026apos;s haemodynamics to treatment based on neurohumoural mechanisms. Treatment options mainly include renin angiotensin aldosterone system (RAAS) inhibitors,\u0026nbsp;\u0026beta;\u0026nbsp;receptor blockers, aldosterone receptor antagonists, positive inotropic drugs, and diuretics\u003csup\u003e[6]\u003c/sup\u003e; Previous studies have shown that dapagliflozin reduces blood volume, increases haematocrit, and enhances the oxygen carrying capacity of the body\u003csup\u003e[7-9]\u003c/sup\u003e. The DAPA-HF test and the latest EMPEROR Reduced test showed that SGLT-2 inhibitors could reduce the risk of cardiovascular death or the composite event endpoint of hospitalization due to HF in patients with HF with reduced ejection fraction (EF%), whether these patients had diabetes or not\u003csup\u003e[10]\u003c/sup\u003e. In addition, CANTOS research has shown that inflammation is an important cardiovascular risk factor, and anti-inflammatory treatment can improve the prognosis of CVDs\u003csup\u003e[11]\u003c/sup\u003e. However, the mechanism by which empagliflozin can treat CHF is not clear. Thus, we established a CHF rat model by ligating the anterior descending branch of the coronary artery in SD rats to study the effect of empagliflozin on heart function during CHF and the possible mechanisms.\u003c/p\u003e"},{"header":"1 Materials and Methods","content":"\u003cdiv id=\"Sec2\" class=\"Section2\"\u003e \u003ch2\u003e1.1 Groupings and processing\u003c/h2\u003e \u003cp\u003e The animal experiment was carried out in strict accordance with the \"Regulations on the Management of Experimental Animals\" issued by the State Council of the People's Republic of China. This experiment was approved by the Experimental Animal Ethics Committee of the Second Affiliated Hospital of Chongqing Medical University. Male SD rats were provided by Chongqing Medical University and were randomly divided into a control group of 15 rats (AMI\u0026thinsp;+\u0026thinsp;NS), an empagliflozin-treated group of 14 rats (AMI\u0026thinsp;+\u0026thinsp;empagliflozin), and a sham-operated group of 11 rats (sham-operated\u0026thinsp;+\u0026thinsp;NS). The ischaemic HF model was established as previously described\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e by ligating the left anterior descending artery in the control group and the empagliflozin-treated group. The sham-operated group were only subjected to threading without ligation at the same site. Postoperative intraperitoneal injection of penicillin (4000 U/d * 3 days) was performed to prevent infection. On the second day after surgery, the control group and sham operation group were given physiological saline by gavage, while the treatment group was given empagliflozin (30 mg/kg/day) by gavage for a total of 16 weeks.\u003c/p\u003e \u003cp\u003eEmpagliflozin (10 mg/tablet) was purchased from Shanghai Bollinger Ingerhan Pharmaceutical Co., Ltd. The rat hypersensitive C-reactive protein (hs-CRP) enzyme-linked immunosorbent assay (ELISA) kit was purchased from Shenzhen Zike Biotechnology Co., Ltd. The IP lysis buffer was obtained from Shanghai Biyuntian Biotechnology Co., Ltd., and the N-terminal pro-B-type natriuretic peptide (NT-proBNP) ELISA kit for rats was purchased from Shanghai Xitang Biotechnology Co., Ltd. iNOS antibodies (Beijing Boorsen Biotechnology Co., Ltd. ), the HX-200 animal ventilator (Chengdu Taimeng Technology Co., Ltd. ), and the Vivid Doppler ultrasound instrument (probe frequency 10 MHz, GE company) were used.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e1.2 Echocardiographic detection of cardiac function and specimen collection\u003c/h2\u003e \u003cp\u003eAfter 16 weeks of gavage, SD rats were intraperitoneally anaesthetized with chloral hydrate, placed on their backs, and fixed on the operating table. The cardiac function of each group of rats was measured by ultrasound. The long axis of the left ventricle was displayed on a two-dimensional ultrasound section, and M-ultrasound was used to measure the left ventricular end diastolic diameter (LVIDd), left ventricular internal diameter (LVIDs), and EF%. After the cardiac function testing, blood was collected from the inferior vena cava, the rats were decapitated, and the heart was removed by thoracotomy. The tissues were washed with physiological saline, and vascular tissue, the atrium, the right ventricle, and fibrotic areas were removed after left ventricular infarction. The remaining noninfarcted myocardium of the left ventricle was prepared into paraffin sections, and the remaining portion was stored in liquid nitrogen for later use. Blood was collected at 950 days, centrifuged for 20 minutes to extract the supernatant, and stored at -20 ℃ for future use.\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.3 Intracellular reactive oxygen species (ROS) levels and mitochondrial membrane potential (MMP) were measured by flow cytometry\u003c/b\u003e \u003c/p\u003e \u003cp\u003eTwenty milligrams of noninfarcted left ventricular myocardial tissue was cut into 1\u0026ndash;2 mm fragments with ophthalmic scissors, 2 ml of 0.25% trypsin was added, and the tissue was digested in a 37\u0026deg;C water bath for 3 minutes, centrifuged at 500 r for 1 minute. Then, 1 ml of foetal bovine serum was added to terminate the digestion. The differential adhesion method was used to separate myocardial cells, and a cell counting plate was used to count the number of myocardial cells. Each group contained 1.0 \u0026times; 10\u003csup\u003e6\u003c/sup\u003e resuspended cells suspended in DCFH-DA diluted 1:1000 with serum-free culture medium. A total of 1.0 \u0026times; 10\u003csup\u003e6\u003c/sup\u003e resuspended cells were added to 0.5 ml of Rh123 staining solution, and ROS levels and the MMP were detected by flow cytometry.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e1.4 ELISA analysis of blood BNP levels\u003c/h2\u003e \u003cp\u003eThe preserved SD rat plasma was tested according to the instructions of the rat BNP kit.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e1.5 ELISA analysis of blood hs-CRP levels\u003c/h2\u003e \u003cp\u003e The preserved SD rat plasma was diluted appropriately and analysed according to the kit instructions. The absorbance value was measured using ELISA at a wavelength of 450 nm, and a standard curve was drawn using the standard sample provided by the kit. Serum levels of hs-CRP in each group were calculated, and each sample was examined 3 times.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e1.6 HE staining and immunohistochemical analysis of iNOS expression\u003c/h2\u003e \u003cp\u003eRat myocardial tissue was fixed with 4% paraformaldehyde for 24 hours and embedded in paraffin (5 \u0026micro;m) for HE staining. The immunohistochemical steps were carried out according to the kit instructions (Beijing Zhongshan Jinqiao Company). The paraffin sections were dewaxed with xylene and rehydrated through a gradient, and antigen repair was performed with citric acid solution. Goat serum sealing was performed at room temperature for 1 hour, and diluted rabbit-derived iNOS polyclonal antibodies (1:250) were added dropwise. The samples were incubated overnight at 4\u0026deg;C. Goat anti-rabbit secondary antibodies were added the next day. The horseradish enzyme-labelled albumin working solution (S-A/HRP) was incubated at room temperature for 30 minutes, followed by DAB staining and haematoxylin staining. The film was sealed, and myocardial morphology and iNOS expression were observed under a microscope. The integrated optical density (IOD) of iNOS-positive myocardial cells in each group was measured using Image-Pro Plus (IPP) software to determine the relative protein expression of iNOS.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e1.7 Statistical analysis\u003c/h2\u003e \u003cp\u003eThe experimental data were analysed with SPSS 21.0 statistical software, and the experimental results were subjected to a normal distribution. Indicators with a normal distribution and homogeneity of variance between groups were compared by ANOVA; otherwise, the rank sum test was used. The difference was statistically significant at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"2 Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n \u003ch2\u003e2.1 Feeding situation\u003c/h2\u003e\n \u003cp\u003eEight SD rats in the model group died, and one rat in the sham surgery group died. The causes of death were infection, acute left HF, and malignant arrhythmia. The remaining 31 SD rats reached the experimental endpoint.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2 Cardiac function test results\u003c/h2\u003e\n \u003cp\u003eAt 16 weeks after ligation of the left anterior descending artery, the control group showed a significant increase in LVIDd and LVIDs (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) compared with the sham-operated group, while LVEF decreased significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Compared with the control group, the empagliflozin treatment group showed a significant reduction in LVIDd and LVIDs (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and a significant increase in LVEF (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), as shown in Table 1 and Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eTable I. Echocardiographic Parameters of Rats with HF Following MI (\u0026chi;\u0026thinsp;\u0026plusmn;\u0026thinsp;s)\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Taba\" border=\"1\"\u003e\n \u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u003cbr\u003e\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSham group\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003econtrol group\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEmpagliflozin group\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4 weeks following MI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLVIDd (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.69\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.64\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLVIDs (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.47\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLVEF (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e90.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e73.3\u0026thinsp;\u0026plusmn;\u0026thinsp;8.21\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e76.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.79\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16 weeks following MI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLVIDd (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLVIDs (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLVEF (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e92.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e70.5\u0026thinsp;\u0026plusmn;\u0026thinsp;9.54\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e85.1\u0026thinsp;\u0026plusmn;\u0026thinsp;6.37\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003e\u003csup\u003e\u0026nbsp;\u003cstrong\u003ea\u003c/strong\u003e\u0026nbsp;\u003c/sup\u003e \u003cstrong\u003eP\u0026lt;0.05, compared with the sham group;\u003c/strong\u003e \u003csup\u003e\u003cstrong\u003eb\u003c/strong\u003e\u003c/sup\u003e\u003cstrong\u003eP\u0026lt;0.05, compared with the control group.\u003c/strong\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3 Myocardial ROS and MMP\u003c/h2\u003e\n \u003cp\u003eCompared with the sham surgery group (107.14\u0026thinsp;\u0026plusmn;\u0026thinsp;4.79), the control group (196.85\u0026thinsp;\u0026plusmn;\u0026thinsp;12.25) and empagliflozin-treated group (133.16\u0026thinsp;\u0026plusmn;\u0026thinsp;12.25) showed significant increases in intracellular ROS in myocardial cells (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The empagliflozin treatment group showed a significant decrease compared to the control group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Compared with that in the sham operation group (104.73\u0026thinsp;\u0026plusmn;\u0026thinsp;4.31), the MMP in the control group (32.76\u0026thinsp;\u0026plusmn;\u0026thinsp;7.7) and empagliflozin treatment group (80.21\u0026thinsp;\u0026plusmn;\u0026thinsp;14.98) decreased. The empagliflozin treatment group showed an increase compared to the control group, as shown in Fig. 2.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003e2.4 Serum BNP levels\u003c/h2\u003e\n \u003cp\u003eCompared to those in the sham surgery group (8.76\u0026thinsp;\u0026plusmn;\u0026thinsp;0.46 \u0026micro;g/L), serum BNP levels were significantly increased in the control group (22.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.23 \u0026micro;g/L) and empagliflozin treatment group (13.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.59 \u0026micro;g/L) (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The empagliflozin treatment group showed a significant decrease compared to the control group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003e2.5 Serum levels of hs-CRP\u003c/h2\u003e\n \u003cp\u003eCompared to those in the sham surgery group (10.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.37 \u0026micro;g/L), serum BNP levels were significantly increased in the control group (29.4\u0026thinsp;\u0026plusmn;\u0026thinsp;1.02 \u0026micro;g/L) empagliflozin treatment group (14.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.53 \u0026micro;g/L) (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The empagliflozin treatment group showed a significant decrease compared to the control group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003e2.6 HE staining and iNOS expression in the myocardium of rats in each group\u003c/h2\u003e\n \u003cp\u003eHE staining showed that in the sham surgery group [percentage of oedematous cells among total cells: (12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13)%], the myocardial fibres were arranged neatly, the cytoplasm was rich and uniform, and the nucleus was intact. The control group showed significant myocardial tissue oedema compared to the sham surgery group [percentage: (79\u0026thinsp;\u0026plusmn;\u0026thinsp;0.53)%] (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), and the myocardial fibres were broken and disordered, there was nuclear disappearance, and a large amount of fibrous tissue formed around the infarcted area. Compared with that in the control group, myocardial tissue oedema in the empagliflozin treatment group was significantly reduced [percentage: (31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29)%] (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The arrangement was relatively neat, the nucleus was relatively intact, and fibrosis around the infarction was reduced, as shown in Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eThe expression level of iNOS [IOD (15.67\u0026thinsp;\u0026plusmn;\u0026thinsp;2.41)] in the sham operation group was very low, while the expression level of iNOS in the control group [IOD (1254\u0026thinsp;\u0026plusmn;\u0026thinsp;23.18)] and empagliflozin treatment group [IOD 109.83\u0026thinsp;\u0026plusmn;\u0026thinsp;15.09)] was significantly higher than that in the sham operation group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05); the expression level of iNOS in the empagliflozin treatment group was significantly lower than that in the control group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), as shown in Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"3 Discussion","content":"\u003cp\u003eIn this study, it was found that empagliflozin had anti-inflammatory effects, reduced myocardial oxidative stress, stabilized cell membrane potential, and inhibited myocardial fibrosis, thereby improving heart function in rats with HF.\u003c/p\u003e \u003cp\u003eEmpagliflozin is a novel oral hypoglycaemic drug that is a SGLT-2i. Previous studies have shown that SGLT-2i can significantly reduce the risk of cardiovascular death and hospitalization rate for HF, but the mechanism of action is still not fully understood. Research has shown that oxidative stress is present in almost all forms of CVD and plays a crucial role in energy regulation within myocardial cells. Oxidative stress is defined as a state in which cells and/or the body produce excessive ROS that exceed endogenous antioxidant defence capabilities, thereby damaging proteins, lipids, and DNA. Active oxygen includes superoxide (O-2 \u0026middot;), hypochlorite (HOCl) and hydrogen peroxide (H2O2). Under normal physiological conditions, the generation of ROS in the heart is minimal, and there is an antioxidant defence system that clears ROS to maintain metabolic balance. However, in response to certain harmful stimuli, cardiac oxidative antioxidant homeostasis is disrupted, and the accumulated O-2 \u0026middot; is highly diffused and damages myocardial cells\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e. In addition, ROS can reduce myocardial cell contraction in a concentration-dependent manner\u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e, leading to a certain degree of cardiac dysfunction \u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e. This study showed a significant increase in myocardial ROS levels in rats with CHF, confirming that CHF rats were in a state of oxidative stress at this time, while myocardial ROS levels in rats treated with empagliflozin were significantly lower than those in the control group. Oxidative stress plays an important role in the occurrence and development of HF; it can mediate cell proliferation, myocardial remodelling, and myocardial apoptosis by activating various signalling pathways, thereby causing further deterioration of cardiac function. Moreover, the role of mitochondrial dysfunction in CVDs has been fully confirmed. A decrease in the MMP is a sign of early apoptosis. This study showed that the MMP of CHF rats was lower than that of sham rats, the MMP of CHF rats was higher than that of control rats after treatment with empagliflozin, and intracellular ROS levels were lower than those in the control group. These results suggested that empagliflozin could stabilize MMP, improve mitochondrial function and increase left ventricular EF% in rats with HF by reducing myocardial ROS production. Empagliflozin can reduce myocardial cell apoptosis and improve cardiac function in HF rats. These results are consistent with previous studies showing that empagliflozin reduces oxidative stress and improves cardiac function\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eInflammation is an important factor in the severity of CHF. The increase in proinflammatory biomarkers in patients with HF is related to disease severity. Inflammatory cytokines not only lead to endothelial dysfunction but also increase the development of myocardial fibrosis\u003csup\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e. Previous studies have shown that inflammation plays a crucial role in ischaemic myocardial damage, leading to the deterioration of cardiac structure and function, thereby promoting structural changes and functional decline in ischaemic heart disease\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. Inflammatory reactions are present during the entire occurrence and development of HF in patients. hs-CRP, which is a biomarker of inflammation, was significantly elevated in the serum of CHF rats compared to sham-operated rats. The serum levels of hs-CRP in the empagliflozin-treated group were decreased compared to those in the control group, indicating that empagliflozin has anti-inflammatory effects. Furthermore, this study showed that myocardial fibres in HF rats were disrupted and arranged in a disordered manner, which was accompanied by the disappearance of cell nuclei and the formation of a large amount of fibrous tissue around the infarcted area. After treatment with empagliflozin, myocardial cell tissue oedema in HF rats was significantly reduced, and fibrosis around the infarcted area was reduced, indicating that empagliflozin could inhibit myocardial fibrosis. In addition, studies have shown a significant increase in iNOS levels in the myocardial cells of patients with HF\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e. INOS can catalyse the synthesis of excess NO from L-arginine, which in turn reacts with O2 to form the strong oxidant peroxynitrite ion (ONOO-), which can cause tissue damage and participate in the development of CHF\u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e. The results of this study showed a significant increase in iNOS levels in the myocardial tissue of HF rats compared to sham-operated rats, which is consistent with the significant increase in iNOS levels in the myocardium of HF patients reported by Umar\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e. However, iNOS levels in the myocardial tissue of HF rats was significantly decreased after treatment with empagliflozin. This finding suggests that empagliflozin can alleviate oxidative stress in CHF rats by downregulating iNOS expression, thereby improving cardiac function in CHF rats.\u003c/p\u003e \u003cp\u003eIn summary, empagliflozin ameliorated cardiovascular risk factors and played a role in cardiovascular protection by exerting anti-inflammatory effects, reducing oxidative stress, stabilizing cell membrane potential, inhibiting myocardial fibrosis, increasing the EF% and other mechanisms. However, its mechanism of action is still not fully understood. We believe that with further research, the mechanism by which empagliflozin affects CHF will be revealed, providing new therapeutic targets for CHF.\u003c/p\u003e \u003cp\u003e \u003cb\u003eConclusion\u003c/b\u003e This study demonstrated that empagliflozin improves cardiac function in the context of CHF. Its mechanism may be related to inhibiting inflammation, reducing myocardial oxidative stress, and improving myocardial fibrosis.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eDeclarations\u003c/h2\u003e \u003cp\u003eEthical Approval\u003c/p\u003e \u003cp\u003eThe animal experiment was carried out in strict accordance with the \"Regulations on the Management of Experimental Animals\" issued by the State Council of the People's Republic of China. This experiment was approved by the Experimental Animal Ethics Committee of the Second Affiliated Hospital of Chongqing Medical University.\u003c/p\u003e \u003cp\u003eCompeting interests\u003c/p\u003e \u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis work was supported by Shandong Province Medical and Health Technology Development Plan Project.\u003c/p\u003e\u003ch2\u003eAuthor contribution\u003c/h2\u003e \u003cp\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Zhenzhen Wang, QianLiu, Xiaofang Wang, Pengpeng Wang,Fenglei Zhang and Zhuwen Wang. The first draft of the manuscript was written by Zhenzhen Wang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e \u003cp\u003eAll source data for this study are available upon reasonable request from the authors.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHU S T, GAO R L, LIU L S, et al.Summary of the 2018 Report on Cardiovascular Diseases in China.Chinese Circulation Journal, 2019,34:209\u0026ndash;220.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHaoG, WangX, ChenZ, et al. Prevalence of heart failure and left ventricular dysfunction in China: the China Hypertension Survey, 2012\u0026ndash;2015. Eur J Heart Fail, 2019, 21:1329\u0026ndash;1337.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMURPHY S P,IBRAHIM N E,JANUZZI J L.Heart failure with reduced ejection fraction: a review.JAMA,2020,324:488\u0026ndash;504.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSIMPSON J,JHUND P S,LUND L H,et al.Prognostic models derived in PARADIGM-HF and validated in AT-MOSPHERE and the Swedish Heart Failure Registry to predict mortality and morbidity in chronic heart failure.JAMA Cardiol,2020,5:432\u0026ndash;441.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUCHMANOWICZ I,LEE C S,VITALE C,et,al.Frailty and the risk of all-cause mortality and hospitalization in chronic heart failure:a meta-analysis.ESC Heart Fail,2020,7:3427\u0026ndash;3437.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePacker M, Anker SD, Butler J, et al. Cardiovascular and renal outcomes with empagliflozin in heart failure. N Engl J Med, 2020, 383: 1413\u0026ndash;1424.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTestani JM, Chen J, McCauley BD, Kimmel SE, Shannon RP. Potential effects of aggressive decongestion during the treatment of decompensated heart failure on renal function and survival. Circulation 2010;122:265\u0026ndash;72.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKataoka H. Biochemical determinants of changes in plasma volume after decongestion therapy for worsening heart failure. J Card Fail 2019;25:213\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOhara K, Masuda T, Murakami T, et al. Effects of the sodium-glucose cotransporter 2 inhibitor dapagliflflozin on flfluid distribution: a comparison study with furosemide and tolvaptan. Nephrology (Carlton) 2019;24:904\u0026ndash;11.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZannad F, Ferreira JP, Pocock SJ, et al.SGLT2 inhibitors in patients with heart failure with reduced ejection fraction:a meta-analysis of the EMPEROR-Reduced and DAPA-HF trials.Lancet,2020,396:819\u0026ndash;829.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRidker PM, Everett BM, Thuren T, et al.Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease.N Engl J Med,2017,377:1119\u0026ndash;1131.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWu H, Zhu Q, Cai M,et al.Effect of Inhibiting Malonyl-CoA Decarboxylase on Cardiac Remodeling after Myocardial Infarction in Rats.Cardiology. 2014,127:236\u0026ndash;244.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHalliwellB. Reactive species and antioxidants. Redox biology is a fundamental theme of aerobic life. Plant Physiol, 2006,141:312\u0026ndash;322.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePalmieri V, Innocenti F, Guzzo A, et al.Left ventricular systolic longitudinal function as predictor of outcome in patients with sepsis.Circ Cardiovasc Imaging,2015,8:e003865.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKwonSH, PimentelDR, RemondinoA, et al. H(2)O༈2༉regulates cardiac myocyte phenotype via concentration-dependent activation of distinct kinase pathways. J Mol Cell Cardiol, 2003,35:615\u0026ndash;621.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSabriA, ByronKL, SamarelAM, et al. Hydrogen peroxide activates mitogen-activated protein kinases and Na+-H + exchange in neonatal rat cardiac myocytes. Circ Res, 1998,82:1053\u0026ndash;1062.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWu Y,Yao YM,Lu ZQ.Mitochondrial quality control mechanisms as potential therapeutic targets in sepsis-induced multiple organ failure. J Mol Med(Berl).2019,97:451\u0026ndash;462.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCantonM, NeverovaI, MenaboR, et al. Evidence of myofibrillar protein oxidation induced by postischemic reperfusion in isolated rat hearts. Am J Physiol Heart Circ Physiol, 2004,286:H870-H877.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee TM,Chang NC,Lin SZ.Dapagliflozin, a selective SGLT2 inhibbitor, attenuated cardiac fibrosis by regulating the macrophage polarization via STAT3 signaling in infarcted rat hearts. Free Radic Biol Med,2017,104:298\u0026ndash;310.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTanajak p, Sa-Nguanmoo P,Sivasinprasasn S, et al.Cardioprotection of dapagliflozin and vildagliptin in rats with cardiac ischemia-reperfusion injury. J Endocrinol,2018,236:69\u0026ndash;84.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBriasoulis A,Androulakis E,Christophides T,et al.The role of inflmmation and cell death in the pathogenesis,progression and treatment of heart failure.Heart Fail Rev,2016,21:169\u0026ndash;176.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWilhelmiMH, LeyhRG, WilhelmiM, et al.Upregulation of endothelial adhesion molecules in hearts with congestive and ischemic cardiomyopathy: immunohistochemical evaluation of inflammatory endothelial cell activation.Eur J Cardiothorac Surg, 2005, 27:122\u0026ndash;127.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUmar S, van der Laarse A.Nitric oxide and nitric oxide synthase isoforms in the normal, hypertrophic, and failing heart.Mol Cell Biochem. 2010,333:191\u0026ndash;201.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLi W, Olshansky B.Inflammatory cytokines and nitric oxide in heart failure and potential modulation by vagus nerve stimulation.Heart Fail Rev. 2011,16:137\u0026ndash;45.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGiordano FJ.Oxygen, oxidative stress, hypoxia, and heart failure.J Clin Invest. 2005,115:500\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"naunyn-schmiedebergs-archives-of-pharmacology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"nsap","sideBox":"Learn more about [Naunyn-Schmiedeberg's Archives of Pharmacology](https://www.springer.com/journal/210)","snPcode":"210","submissionUrl":"https://submission.nature.com/new-submission/210/3","title":"Naunyn-Schmiedeberg's Archives of Pharmacology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Chronic heart failure, Empagliflozin, Reactive oxygen species, Hypersensitive C-reactive protein, Membrane potential","lastPublishedDoi":"10.21203/rs.3.rs-3107228/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3107228/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eObjective\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTo examine the effect of empagliflozin on cardiac function in rats with chronic heart failure and the possible mechanism.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eForty 6-week-old male SD rats were randomly divided into the control group, empagliflozin treatment group, and sham-operated group. SD rats in the control group and empagliflozin treatment group were subjected to ligation of the anterior descending coronary artery to induce an acute myocardial infarction model. SD rats in the sham-operated group were only subjected to threading of the anterior descending branch of the coronary artery without ligation. On the second day after surgery, the control group and sham operation group were given physiological saline by gavage, while the empagliflozin treatment group was given empagliflozin (30 mg/kg/day) by gavage. Sixteen weeks later, cardiac function, intracellular reactive oxygen species (ROS) levels, mitochondrial membrane potential (MMP), serum brain natriuretic peptide, hypersensitive C-reactive protein (hs-CRP), iNOS expression levels and myocardial morphological changes were observed.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eCompared with that in the control group, heart function in the empagliflozin treated group was significantly improved, MMP was increased, intracellular ROS levels were decreased, and NT -proBNP and hs-CRP were significantly reduced, and HE staining showed that the cell oedema was less than that in the control group, tissue arrangement was more orderly, and iNOS expression was inhibited.\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e \u003cp\u003eEmpagliflozin can improve cardiac function in rats with chronic heart failure, and the mechanism may involve inhibiting inflammation, reducing myocardial oxidative stress, and improving myocardial fibrosis.\u003c/p\u003e","manuscriptTitle":"Empagliflozin Improves Cardiac Function in Rats with Chronic Heart Failure","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-06-30 17:13:00","doi":"10.21203/rs.3.rs-3107228/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2023-07-05T05:27:35+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-07-04T21:32:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"d72b0b06-982a-4b0e-8e47-a9af651212be","date":"2023-06-28T23:45:10+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2023-06-28T18:54:31+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-06-27T22:32:17+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-06-27T22:32:16+00:00","index":"","fulltext":""},{"type":"submitted","content":"Naunyn-Schmiedeberg's Archives of Pharmacology","date":"2023-06-25T14:20:14+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"naunyn-schmiedebergs-archives-of-pharmacology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"nsap","sideBox":"Learn more about [Naunyn-Schmiedeberg's Archives of Pharmacology](https://www.springer.com/journal/210)","snPcode":"210","submissionUrl":"https://submission.nature.com/new-submission/210/3","title":"Naunyn-Schmiedeberg's Archives of Pharmacology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"9f8c1152-63db-42f0-810e-427317852648","owner":[],"postedDate":"June 30th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2023-10-16T22:29:02+00:00","versionOfRecord":{"articleIdentity":"rs-3107228","link":"https://doi.org/10.1007/s00210-023-02655-7","journal":{"identity":"naunyn-schmiedebergs-archives-of-pharmacology","isVorOnly":false,"title":"Naunyn-Schmiedeberg's Archives of Pharmacology"},"publishedOn":"2023-08-11 21:57:17","publishedOnDateReadable":"August 11th, 2023"},"versionCreatedAt":"2023-06-30 17:13:00","video":"","vorDoi":"10.1007/s00210-023-02655-7","vorDoiUrl":"https://doi.org/10.1007/s00210-023-02655-7","workflowStages":[]},"version":"v1","identity":"rs-3107228","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3107228","identity":"rs-3107228","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}