{"paper_id":"380a82a8-ac36-486f-8621-163d50ad0fa7","body_text":"Manuscript accepted for publication\nProvisionally accepted for publication\nNARRATIVE REVIEW\nAntioxidant therapy in endometriosis treatment: systematic review\nAntioxidant therapy in endometriosis treatment\nLaura Pivazyan 1, Eva Nakhapetyan 2, Sapiyat Isaeva 1, Veronika Tarlakyan 3,*, Anastasia Laevskaya 4, Eduard Ayryan 3, Valeriia Seregina 1\n1 FS BI «National medical research center for obstetrics, gynecology and perinatology named after academician V.I.Kulakov» Ministry of health \nof the Russian Federation, Moscow, Russia.\n2 P irogov Russian National Research Medical University , Moscow, Russia.\n3 I .M. Sechenov First Moscow State Medical University (Sechenov University) , Moscow, Russia.\n4 Botkin Hospital, Moscow, Russia.\n*C\norresponding author: Veronika Tarlakyan MBBS – I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991,\nMoscow, Russia.\nEmail: vtarlakyan00@mail.ru. \nORCID: 0000-0003-1163-2874. \nDoi\n: 10.36129/jog.2025.239 \n\nManuscript accepted for publication\n \n \nABSTRACT \nObjective. To summarize current knowledge on the effectiveness of antioxidant therapy in endometriosis treatment. \nMaterials and Methods. A systematic review was conducted per PRISMA guidelines and registered in PROSPERO 2023 CRD42023454705. \nStudies published until November 2024 were identified through PubMed, The Cochrane Library, ClinicalTrials.gov, Google Scholar, and \nMEDLINE. COVIDENCE software was used for screening. Risk of bias was assessed using the Cochrane Handbook. \nResults. Out of 512 studies, 11 were included in the systematic review. Endometriotic cysts weight and volume are dose-dependent \nparameters that are significantly lower in antioxidant treatment groups (p <0.05) Neither histological cell scores nor trichrome fibrosis scores \nshowed statistically significant differences among treatment and control groups (p > 0.05) in 2 out of 3 studies. Significantly lower levels of \nTOS, NO and OSI are evaluated in the antioxidant group compared to control. However, no significant differences were observed in MDA, SOD \nand CAT levels. The number of follicles was significantly increased, and the atretic follicles number was significantly decreased after therapy (p \n<0.05). The IVF, cleavage, blastocyst formation rates and blastocyst number were significantly higher in treatment group compared the control. \nConclusions. Antioxidants may be considered as a possible component of endometriosis therapy to potentially enhance fertility outcomes and \nslow disease progression, though current evidence is preliminary and requires further validation. \nKey words \nEndometriosis; antioxidants; treatment; oxidative stress. \nAbbreviations: TOS, total oxidant status; NO, nitric oxide; OSI, oxidative stress index; MDA, malondialdehyde; SOD, superoxide dismutase; \nCAT, catalase; IVF, In vitro fertilization.  \n \nIntroduction  \nEndometriosis is an estrogen-dependent inflammatory gynecological disease defined by the presence of endometrial-like mucosa outside the \nuterine cavity. The pathogenesis of endometriosis is supported by several theories, such as immunological, implantation (Sampson's theory), \ndysontogenetic, dissemination, metaplastic, genetic, hormonal, etc. [1] Endometriosis has an impact on fertility, affecting the ovarian reserve, \nembryo quality, implantation and normal anatomical structure of the reproductive organs and surrounding tissues . However, the mechanisms \nleading to endometriosis-associated infertility are not fully understood. Currently, the role of oxidative stress (OS) leading to iron metabolism \ndisorders in the pathogenesis of endometriosis is widely discussed.  Endometriotic lesions are resistant to ferroptosis - iron-mediated \nprogrammed non-apoptotic cell death, which allows their implantation in the peritoneal cavity [2]. There is a need for further research in this \narea due to its high relevance, theoretical and practical importance. \nA microenvironment with a high level of reactive oxygen species (ROS), free radicals and iron is created as a result of cyclic changes in ectopic \nendometriotic lesions, which increases their adhesion and the progression of the disease.  \n\nManuscript accepted for publication\n \n \nThe presence of ROS in cells is a physiological process due to their formation in normal oxidative metabolism. They control the ovarian cycle, \nsteroidogenesis and ovulation [3]. However, the imbalance between free radicals and the antioxidant system causes oxidative stress, leading to \na reduction in oocyte quality [4]. \nIn this systematic review, we observe the efficiency of antioxidants supplementation in endometriosis treatment.  \n \nMaterials and methods \nStudy design \nOur systematic review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses \n(PRISMA) statement [5]. \nThe present systematic review has been registered in the PROSPERO international prospective registry of systematic reviews by the National \nInstitute of Health Research (NIHR). The registration number is PROSPERO 2023 CRD42023454705.  \nSearch strategy \nTo identify relevant articles, we conducted an electronic database search using several databases: PubMed, Google Scholar, ClinicalTrials.gov, \nCochrane library to identify studies using key words and MeSH terms. The date of the last screening was November 26, 2024. Using the \nadvanced search tool on PubMed, the following combination of key words was used: ((endometriosis) OR (endometrioma)) AND (antioxidants) \nAND (oxidative stress) AND (treatment). No filters or limits were used. Additionally, the search was conducted using MeSH terms \n(endometriosis [MeSH Terms]) AND ((antioxidants[MeSH Terms]) AND (treatment [MeSH Terms]) AND (oxidative stress [MeSH Terms]). \nThe Cochrane Library electronic database search strategy was conducted. The combination of the search was as follows: ((endometriosis) OR \n(endometrioma)) AND (antioxidants) AND (oxidative stress) AND (treatment). No filters or limits were used. MeSH terms were also screened \n(MeSH descriptor: [Endometriosis] explode all trees and with qualifier(s): [antioxidants - MeSH]). \nThe search was also conducted in the ClinicalTrials.gov electronic database using an advanced search combination: endometriosis | \nantioxidants.  \n \nStudy selection \nFor search conducting and further screening COVIDENCE software was used. To ensure the quality and accuracy of the search results, two \ninvestigators performed the search independently. After the initial search, all articles were reviewed based on their titles and abstracts. The full \ntexts of the studies that appeared to be appropriate according to their titles and abstracts were reviewed. Potential trials were also identified by \nsearching the reference lists of the eligible trials. We included randomized (RCTs) and non-randomized clinical trials. Only articles written in \n\nManuscript accepted for publication\n \n \nEnglish were included. Abstracts from congresses and unpublished articles were not included. As this is a review of published studies, \nInstitutional Review Board (IRB) approval was not sought. \nTwo investigators (E.N., I.S) independently read the full texts of the preselected articles to verify their eligibility. Any studies with duplicate \nrecords were excluded. To minimize potential bias during the review process, any disagreements about the inclusion or exclusion of \npreselected studies were resolved with the help of a third author (A.L). \nInclusion criteria \nThe inclusion criteria specified autograft endometriosis mice or rat models and women with endometriosis related infertility, receiving \nantioxidant therapy.  \nStudies that described high levels of oxidative stress markers due to non endometriosis-related reasons, phytoalexins, antioxidant decoctions \nas a therapy were excluded.  \nData Extraction and quality assessment  \nThe studies included were independently collected by two authors (E.N., I.S) using a standardized data extraction procedure. We obtained the \nfollowing characteristics from our studies: study design, type of animal model, types of antioxidants and regimens used, and the number of \npatients in each groups and the follow-up duration. \nThe analysis in animal models was aimed to evaluate the level of oxidative stress markers, embryo and oocyte quality, implant weight, volume \nand histological cell scores of endometriotic lesions after antioxidant therapy \nThe analysis of human studies was aimed to establish the pregnancy outcomes in addition to previously mentioned parameters. \nRisk of bias was assessed for each included study using the Cochrane Handbook for Systematic Reviews of Interventions [6]. Two reviewers \n(V.T., A.L) independently assessed the quality of the selected studies. A third investigator (L.P) was involved in the case of inconsistencies. In \naccordance with the Cochrane Handbook for Systematic Reviews of Interventions, the RoB 2 tool [7] was used to assess the risk of bias for \nrandomized controlled trials and ROBINS-I [8] for non-randomized trials, SYRCLE’s RoB tool for animal model studies [9].  \n \nResults  \nSummary of Included Studies  \nThe study selection process is illustrated by the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flow chart \ndiagram (Figure 1).  \n\nManuscript accepted for publication\n \n \nA total of 512 publications were identified through an electronic database search of PubMed, Google Scholar, and ClinicalTrials.gov., Cochrane \nlibrary.  \nOf these, 425 studies were screened for title and abstract. 388 were excluded, 38 were selected for eligibility assessment. After screening the \nfull-text articles, 27 were excluded for failing to meet the eligibility criteria. The references of the selected studies were additionally searched for \nother eligible studies and 7 studies were identified. Finally, 11 trials that met the criteria were included in the systematic review. A total of 73 \nrats, 14 mice and 759 women from ten trials were analyzed. The detailed summary of the studies analysis is shown in Table 1-2. \nAntioxidants effectiveness in animal population  \nIn 4 studies, endometriosis was induced by transplanting autologous uterine tissue onto the peritoneal wall of female Wistar albino rats [10,11] \nand female NMRI mice [12,13]. \nThe vitamin C effectiveness in animal population \nOzlem Ulas Erten et al [10] and Yildirim Durak et al [11] evaluated the efficacy of vitamin C in the prevention and regression of endometriotic \nimplant development in an experimentally induced autografted endometriosis rat model. Implant weight and volume, histological cell scores and \ntrichrome fibrosis scores were measured. Both authors suggest that histological scores are independent of vitamin C dosage, in contrast to \nimplant volume. However, the exact reason for their insensitivity is not mentioned. It could either be due to the small number of animals \nincluded or the lack of direct effects. \nHayedeh Hoorsan et al [12] conducted a study on the efficacy of vitamin C endometriosis treatment in the NMRI mouse model. In contrast to \nthe previous two studies, the authors found a significant difference not only in the volume of endometriotic implants but also in the trichrome \nfibrosis scores (p=0.03). Follicle, atretic follicle and corpus luteum counts were also measured. The number of follicles was significantly \nincreased (p=0.0005) and the number of atretic follicles was significantly decreased (p=0.006) after vitamin C therapy. \nL-arginine, L-carnitine effectiveness in animal population \nThe other study based on the induced endometriosis mouse model was conducted by Eshrat Kalehoei et al [13]. The authors compared the \neffects of L-arginine (LA), L-carnitine (LC), bone morphogenetic stem cells (BMSC-CM) on endometriosis-induced oocyte quality and levels of \noxidative stress markers. In the endometriosis group, mice treated with LC, LA or BMSC-CM had significantly lower levels of oxidative stress \nmarkers compared to control. In normal and endometriosis treatment groups In vitro fertilisation (IVF), cleavage and blastocyst formation rates \nwere significantly improved compared to the control (p < 0.05).  \nAntioxidants effectiveness in human population  \nOther 7 studies were based on the follicular fluid and plasma samples collected from women with endometriosis related infertility.  \nThe vitamin C effectiveness in human population \n\nManuscript accepted for publication\n \n \nIn human population, the efficacy of vitamin C supplementation was analyzed by Xiang Lu et al [14]. There was no significant difference in \nfertilization, implantation and pregnancy rates between all participants. The number of oocytes and frozen embryos in endometriosis groups \nwas significantly lower than in control (P<0.05).  Treatment with vitamin C for 2 months improved its serum and follicular fluid concentration in \npatients with endometriosis, however did not affect oxidative stress markers rate. The results could be as follows because of several limitations: \nsmall sample size and only one time point measurement (2 months of vitamin C supplementation): comparison of different time points was not \nperformed.  \nN-acetyl-cysteine, L-carnitine effectiveness in human population \nVanessa S. I. et al. conducted two studies [15,16] in which the percentage of meiotically normal oocytes in metaphase II, presumptive zygotes, \ncleavage rate, blastocyst formation rate and hatching rate were measured. The number of meiotically abnormal and normal metaphase II \noocytes was similar in all 9 groups. The authors suggest that follicular fluid (FF) from infertile women with endometriosis increases the \npercentage of meiotically abnormal oocytes. There was no significant difference between groups in cleavage (p=0.54) and blastocyst formation \n(p=0.4349) rates. However, the hatching rate was higher in the control follicular fluid group than in the endometriosis follicular fluid (EFF) group. \nThe addition of antioxidants in CFF groups did not affect the hatching rate. The addition of N-acetylcysteine reduces the destructive effects of \nFF on the oocyte meiotic spindle and increases hatching rate.  The addition of L-carnitine completely prevents this destructive effect on the \nmeiotic spindle, but is less effective in terms of hatching rate. \nThe vitamin C and vitamin E combination effectiveness in human population.  \nThe effect of combined vitamin C + vitamin E treatment was evaluated by Jennifer Mier-Cabrera et al [17], Nalini Santanam et al [18] and Leila \nAmini et al [19].  \nJennifer Mier-Cabrera et al [17] analyzed the lipid hydroperoxide (LOOH) and malondialdehyde (MDA) rate in plasma and peritoneal fluid. \nThere was a statistically significant difference in plasma LOOH and MDA concentrations between control and treatment groups.  Leila Amini et \nal [19] held randomized, triple-blind placebo-controlled clinical trial, where statistically reduced MDA (p=0.002) and reactive oxygen species \n(ROS) (p < 0.001) levels in treatment group compared to placebo were evaluated. \nAnti- myeloperoxidase therapy human population \nNalini Santanam et al [18] suggested that the level of myeloperoxidase (MPO) - one of the oxidative stress markers - depends on the severity \nof endometriosis. Mean MPO levels in follicular fluid collected from women with severe endometriosis were significantly higher than in control \nand mild endometriosis groups. Combination antioxidant treatment did not significantly reduce MPO levels in both groups. \nAstaxanthin therapy in human population \nSahar Rostami et al. conducted a study on the efficacy of astaxanthin (AST) on oxidative stress markers, cytokine levels and associated \nreproductive technology (ART) outcomes in infertile women with endometriosis [20].  All parameters were reduced after antioxidant therapy \n\nManuscript accepted for publication\n \n \nexcept serum catalase (CAT), IL-1b, IL-6 levels. Embryo quality, number of metaphase II oocytes improved significantly after therapy. However, \nthe number of embryos transferred, fertilisation rate and pregnancy rate were similar in both groups. \nVisualisation tools were provided by the ROBVIS application [21]. According to the ROBINS-I tool, the overall risk of bias for non-randomised \ntrials was 66,7 % low and 33,3% serious (Figure 2). Based on the RoB 2 tool (Figure 3), randomized trials had a 75% chance of low risk of bias \nand an 25% chance of some concern regarding the overall risk of bias.  The SYRCLE’s RoB tool was used to assess the quality of included \nanimal studies (Figure 4). The risk of allocation concealment and random housing could not be confirmed because none of the studies offered \ncomplete information.  \n \nDiscussion \nThere is increasing evidence to suggest that specific diet patterns and nutrients may modulate the pathophysiological processes underlying \nendometriosis.  \nIn this systematic review, we evaluated the efficiency of antioxidants supplementation in endometriosis treatment. We found out that \nantioxidants reduce the severity of endometriosis symptoms by affecting the pathogenesis of the disease.  \nOxidative stress occurs when the balance between reactive oxygen species production and antioxidant capacity is disturbed, either by \ninsufficient antioxidant protection or by increased ROS production. The relationship between ROS production and the progression of \nendometriosis has been studied previously [22]. Due to dysregulation of iron metabolism, these abnormal endometriotic lesions are thought to \nbe resistant to ferroptosis. Ferroptosis is a form of regulated, iron-catalyzed cell death caused by excessive lipid peroxidation in cell \nmembranes. This process was first described by Dixon in 2012 [23].  \nLi B et al [24] found out that there was an excess expression of ferroptosis-associated genes in the ectopic and eutopic endometrium in \npatients with endometriosis, showing a general trend towards inhibition of the ferroptosis pathway. Increased transferrin receptors (TFR1) and \nRas gene mutations in abnormal endometriotic cells directly affect ferroptosis resistance. A local imbalance in iron homeostasis leads to \noxidative stress in the intraperitoneal cavity, inflammation and ferroptosis in intact peripheral tissues. Iron-dependent ROS synthesis is based \non the Fenton reaction: Fe2+ + H2O2 → Fe3+ + OH- + OH-.  As a result, a hydroxyl radical (-OH) is formed, leading to lipid peroxidation and \naccumulation of lipid LOOH, which damages the membrane.  This is why ectopic endometriotic tissue has higher levels of lipid peroxidation \nproducts than normal endometrial tissue. This is also confirmed by other studies [17, 25].  \nIn addition, we observe changes in enzyme levels - SOD and indicators such as TAC, TOS and OSI in serum and FF. The decrease in TAC and \nSOD between patients with and without endometriosis is confirmed. It is noted that there was a significant difference in this indicator in FF as \nopposed to serum between both groups [14]. Total antioxidant response (TAR) is also lower in patients with endometriosis, leading to an excess \nof OSI [26]. Treatment with AST improved TAC and SOD levels [19].  LC and LA administration also improved the TAC, reduced TOS, NO and \nOSI (P<0.05) [16]. However, vitamin C treatment showed no difference in oxidative stress markers and enzyme levels [14]. But there is \nevidence that vitamin C prevents the progression of endometriotic lesion development by reducing their weight, size and volume [10-12]. \n\nManuscript accepted for publication\n \n \nVitamin C and vitamin E combination significantly suppressed levels of MPO (a neutrophil marker that is increased due to oxidative stress and \ndepends on the severity of endometriosis) in FF [18]. These findings support previous data [26].  \nIt should be mentioned that immune cells play a crucial role in ectopic endometriotic lesions detection and elimination.  It is known that \noxidative stress impairs the efficiency of the immune system, leading to reduced recognition of abnormal endometrial tissue, allowing its \ninvasion, accumulation and growth in the pelvic and abdominal cavity. Antioxidants are known to stimulate the whole process of phagocytosis \n[27]. Yildirim Durak et al [11] found that NK cell (Natural killer cells) levels were significantly lower in control groups than in those on antioxidant \ntherapy (P < 0.01). Similar results have been reported in other studies [28,29]. It should be noted that the decrease in cellular immunity \ncorrelates with the severity of the disease. Whether this decrease in NK cells is a cause or a consequence of the severity of endometriosis \nremains unclear. The reduction in cellular immunity is related to the \"endometriotic disease theory\", also known as Sampson's theory, according \nto which the most important factor in the development of endometriosis is not the initial implantation in the peritoneal cavity, but cell mutations \nthat cannot be eliminated due to the reduced number of immune cells.  It is these ectopic endometriotic cells, ignored by regulatory factors in \nthe peritoneal fluid, that trigger the disease [30].  \nAll of the above factors affect fertility in women with endometriosis.  The granulosa cells and the surrounding cumulus cells in the follicle are \ninvolved in the maturation of the oocyte. This process depends on the intrafollicular environment. If it is damaged, the developmental \ncompetence of the oocytes, the quality of the embryos and the clinical pregnancy rate are reduced. In the case of antioxidant therapy, IVF, \ncleavage and blastocyst formation rates are increased compared to no treatment. It is also important to highlight that this finding is potentially \nhelpful for translation into clinical practice [13-16,19]. High-level antioxidant diet can significantly influence inflammatory processes, which are \ndirectly related to the pathophysiology of endometriosis.  \n \nStrengths and limitations of the study \nThe limitations we encountered were mainly related to the available data sources. The patients were not similar between studies: rats and mice \nwith induced endometriosis, human. The heterogeneity of the antioxidants should also be mentioned. A total of 6 antioxidants were included in \nthis review, but it is difficult to compare them because of differences in regimen and dosage in each study. Studies in animal models have a \nlower quality of evidence than those in humans. It is important to emphasize that more research is needed in human to assess the clinical \nrelevance and to establish the efficacy of antioxidants, as clinical trials evaluating their effects on endometriosis are still relatively limited.  \nThe main strength of this study is that we observed antioxidant supplementation as a therapy that affect oxidative stress – the main aspect of \nendometriosis pathogenesis. All previously published reviews were aimed to analyze the types of oxidative stress markers and their levels in \npatients with endometriosis, but did not observe and summarize any medications for their reduction.  \nImplications for future studies may include investigating the development of targeted antioxidant treatment, the possibility of delivering \nantioxidants directly to endometriotic lesions. This could potentially increase the efficacy of antioxidant therapy and minimize potential side \neffects.  \n\nManuscript accepted for publication\n \n \nConclusion \nAntioxidants may be considered as a possible component of endometriosis therapy to potentially enhance fertility outcomes and slow disease \nprogression, though current evidence is preliminary and requires further validation. This type of treatment reduces oxidative stress markers \nconcentration, suspend endometriotic lesions progression and improve oocyte developmental competence. However, there is still controversy \nabout the antioxidant treatment as a monotherapy of endometriosis. That is why more clinical trials to make stronger recommendations is \nneeded. \n \nCompliance with Ethical Standards \nAuthors’ contribution   \nL.P ., E.N., S.I., V.T., A.L., and V.S. contributed to **Conceptualization**. E.N., I.S., and A.L. were responsible for **Data curation** and **Writing \n– original draft**. L.P ., V.T., and V.S. contributed to **Writing – review & editing**. All authors read and approved the final version of the \nmanuscript. \nFunding \nThe authors received no financial support for the research, authorship, and/or publication of this article. \nStudy registration \nPROSPERO CRD42023454705. \nDisclosure of interests \nThe authors declare that they have no competing interests. \nEthical approval \nNot applicable. This article is a narrative review and does not involve human participants, animal subjects, or medical records. \nInformed consent  \nNot applicable. \nData sharing  \nData sharing is not applicable to this article as no new data were created or analyzed in this study. \n \n\nManuscript accepted for publication\n \n \nReferences \n[1] Czyzyk A, Podfigurna A, Szeliga A, Meczekalski B. Update on endometriosis pathogenesis. Minerva Ginecol. 2017;69(5):447–461. \ndoi:10.23736/S0026-4784.17.04048-5. \n[2] Ng SW, Norwitz SG, Taylor HS, Norwitz ER. Endometriosis: The role of iron overload and ferroptosis. Reprod Sci. 2020;27(7):1383–1390. \ndoi:10.1007/s43032-020-00164-z. \n[3] Kobayashi H, Yoshimoto C, Matsubara S, Shigetomi H, Imanaka S. Current understanding of and future directions for endometriosis-related \ninfertility research with a focus on ferroptosis. Diagnostics (Basel). 2023;13(11):1926. doi:10.3390/diagnostics13111926. \n[4] Kao SH, Huang HC, Hsieh RH, Chen SC, Tsai MC, Tzeng CR. Oxidative damage and mitochondrial DNA mutations with endometriosis. Ann \nNY Acad Sci. 2005;1042:186–194. doi:10.1196/annals.1338.021. \n[5] Page MJ, Moher D, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. PRISMA 2020 explanation and elaboration: updated guidance \nand exemplars for reporting systematic reviews. BMJ. 2021;372:n160. doi:10.1136/bmj.n160. \n[6] Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, et al. Cochrane Handbook for Systematic Reviews of Interventions version \n6.1 (updated September 2020). Cochrane, 2020. Available from: www.training.cochrane.org/handbook. \n[7] Sterne JAC, Savović J, Page MJ, Elbers RG, Blencowe NS, Boutron I, et al. RoB 2: a revised tool for assessing risk of bias in randomized \ntrials. BMJ. 2019;366:l4898. \n[8] Sterne JAC, Hernán MA, Reeves BC, Savović J, Berkman ND, Viswanathan M, et al. ROBINS-I: a tool for assessing risk of bias in \nnonrandomized studies of interventions. BMJ. 2016;355:i4919. \n[9] Hooijmans CR, Rovers MM, de Vries RB, Leenaars M, Ritskes-Hoitinga M, Langendam MW. SYRCLE's risk of bias tool for animal studies. \nBMC Med Res Methodol. 2014;14:43. doi:10.1186/1471-2288-14-43. \n[10] Erten OU, Ensari TA, Dilbaz B, Cakiroglu H, Altinbas SK, Çaydere M, et al. Vitamin C is effective for the prevention and regression of \nendometriotic implants in an experimentally induced rat model of endometriosis. Taiwan J Obstet Gynecol. 2016;55(2):251–257. \ndoi:10.1016/j.tjog.2015.07.004. \n[11] Durak Y, Kokcu A, Kefeli M, Bildircin D, Çelik H, Alper T. Effect of vitamin C on the growth of experimentally induced endometriotic cysts. J \nObstet Gynaecol Res. 2013;39(7):1253–1258. doi:10.1111/jog.12050. \n[12] Hoorsan H, Simbar M, Tehrani FR, Fathi F, Mosaffa N, Riazi H, et al. The effectiveness of antioxidant therapy (vitamin C) in an \nexperimentally induced mouse model of ovarian endometriosis. Womens Health (Lond). 2022;18:17455057221096218. \ndoi:10.1177/17455057221096218. \n\nManuscript accepted for publication\n \n \n[13] Kalehoei E, Moradi M, Azadbakht M, Zhaleh H, Abadi SAL, Mahdiuni H, et al. Therapeutic effects of L-arginine, L-carnitine, and \nmesenchymal stem cell-conditioned medium on endometriosis-induced oocyte poor quality in an experimental mouse model. J Obstet \nGynaecol Res. 2023;49(4):1180–1188. doi:10.1111/jog.15569. \n[14] Lu X, Wu Z, Wang M, Cheng W. Effects of vitamin C on the outcome of in vitro fertilization-embryo transfer in endometriosis: A randomized \ncontrolled study. J Int Med Res. 2018;46(11):4624–4633. doi:10.1177/0300060518786918. \n[15] Giorgi VS, Da Broi MG, Paz CC, Ferriani RA, Navarro PA. N-acetyl-cysteine and l-carnitine prevent meiotic oocyte damage induced by \nfollicular fluid from infertile women with mild endometriosis. Reprod Sci. 2016;23(3):342–351. doi:10.1177/1933719115602772. \n[16] Giorgi VSI, Ferriani RA, Navarro PA. Follicular fluid from infertile women with mild endometriosis impairs in vitro bovine embryo \ndevelopment: Potential role of oxidative stress. Rev Bras Ginecol Obstet. 2021;43(2):119–125. doi:10.1055/s-0040-1718443. \n[17] Mier-Cabrera J, Genera-García M, De la Jara-Díaz J, Perichart-Perera O, Vadillo-Ortega F, Hernández-Guerrero C. Effect of vitamins C \nand E supplementation on peripheral oxidative stress markers and pregnancy rate in women with endometriosis. Int J Gynaecol Obstet. \n2008;100(3):252–256. doi:10.1016/j.ijgo.2007.08.018. \n[18] Santanam N, Zoneraich N, Parthasarathy S. Myeloperoxidase as a potential target in women with endometriosis undergoing IVF. Reprod \nSci. 2017;24(4):619–626. doi:10.1177/1933719116667225. \n[19] Amini L, Chekini R, Nateghi MR, Haghani H, Jamialahmadi T, Sathyapalan T, et al. The effect of combined vitamin C and vitamin E \nsupplementation on oxidative stress markers in women with endometriosis: A randomized, triple-blind placebo-controlled clinical trial. Pain Res \nManag. 2021;2021:5529741. doi:10.1155/2021/5529741. \n[20] Rostami S, Alyasin A, Saedi M, Nekoonam S, Khodarahmian M, Moeini A, et al. Astaxanthin ameliorates inflammation, oxidative stress, \nand reproductive outcomes in endometriosis patients undergoing assisted reproduction: A randomized, triple-blind placebo-controlled clinical \ntrial. Front Endocrinol. 2023;14:1144323. doi:10.3389/fendo.2023.1144323. \n[21] McGuinness LA, Higgins JPT. Risk-of-bias VISualization (robvis): An R package and Shiny web app for visualizing risk-of-bias \nassessments. Res Syn Meth. 2020;12(1):55–617. doi:10.1002/jrsm.1411. \n[22] Scutiero G, Iannone P, Bernardi G, Bonaccorsi G, Spadaro SA, Volta CA, et al. Oxidative stress and endometriosis: A systematic review of \nthe literature. Oxid Med Cell Longev. 2017;2017:7265238. doi:10.1155/2017/7265238. \n[23] Dixon SJ, Lemberg KM, Lamprecht MR, Skouta R, Zaitsev EM, Gleason CE, et al. Ferroptosis: An iron-dependent form of nonapoptotic cell \ndeath. Cell. 2012;149(5):1060–1072. doi:10.1016/j.cell.2012.03.042. \n[24] Li B, Duan H, Wang S, Li Y . Ferroptosis resistance mechanisms in endometriosis for diagnostic model establishment. Reprod Biomed \nOnline. 2021;43(1):127–138. doi:10.1016/j.rbmo.2021.04.002. \n\nManuscript accepted for publication\n \n \n[25] de Lima CB, Cordeiro FB, Camargo M, Zylbersztejn DS, Cedenho AP , Bertolla RP, et al. Follicular fluid lipid peroxidation levels in women \nwith endometriosis during controlled ovarian hyperstimulation. Hum Fertil (Camb). 2017;20(1):48–54. doi:10.1080/14647273.2016.1246753. \n[26] ODF, Waelkens E, Peterse DP , Lebovic D, Meuleman C, Tomassetti C, et al. Evaluation of total, active, and specific myeloperoxidase \nlevels in women with and without endometriosis. Gynecol Obstet Investig. 2018;83(2):133–139. doi:10.1159/000475664. \n[27] Assaf L, Eid AA, Nassif J. Role of AMPK/mTOR, mitochondria, and ROS in the pathogenesis of endometriosis. Life Sci. 2022;306:120805. \ndoi:10.1016/j.lfs.2022.120805. \n[28] Fan D, Wang X, Shi Z, Jiang Y, Zheng B, Xu L, et al. Understanding endometriosis from an immunomicroenvironmental perspective. Chin \nMed J (Engl). 2023;136(16):1897–1909. doi:10.1097/CM9.0000000000002649. \n[29] Wang L, Li L, Li Y, Huang C, Lian R, Wu T, et al. History of endometriosis is associated with decreased peripheral NK cytotoxicity and \nincreased infiltration of uterine CD68+ macrophages. Front Immunol. 2021;12:711231. doi:10.3389/fimmu.2021.711231. \n[30] Chen S, Liu Y , Zhong Z, Wei C, Liu Y , Zhu X. Peritoneal immune microenvironment of endometriosis: Role and therapeutic perspectives. \nFront Immunol. 2023;14:1134663. doi:10.3389/fimmu.2023.1134663. \n \n \n \n \n \n \n \n \n \n \n \n \n \n\nManuscript accepted for publication\n \n \nTable 1. Description of selected studies included in the review (rats and mice) \nFirst author, year \nof publication \nTitle  Population Follow up \nperiod  \nIntervention  Comparison Outcomes  \nOzlem Ulas Erten \net al., 2016 \n[10] \nVitamin C is effective for \nthe prevention and \nregression of \nendometriotic implants in \nan experimentally induced \nrat model of endometriosis \n \n \nFemale Wistar Albino Rats \n(n=33) \n \nWeight=209g-270g \n \nA group (n=11)  \nB group (n=11)  \nC group (n=11)  \n \n \n42 days  Surgical induced endometriosis \n(autograft model) \n \nA group: 1\nst operation + intravenous \nvitamin C 500mg/kg every 2 days \n \nB group: 1st operation;  2nd operation + \nintravenous vitamin C 500 mg/kg every 2 \ndays \n \nC group (1st operation;  2nd operation) \nVitamin C vs no \nvitamin C \nin all groups \nImplant volume at the 2nd operation (mm3)   \nImplant volume at the 3rd operation (mm3)  \nWeight 1 (initial) (g) \nWeight 2 (final) (g)  \nHistological cell scores  \nTrichrome fibrosis scores \n \n \n \nYildirim Durak et \nal., 2013 \n[11] \nEffect of vitamin C on the \ngrowth of experimentally \ninduced endometriotic \ncysts. \nFemale Wistar Albino Rats \n(n=40) \n \nV1 group (n=10)  \nV2 group (n=10) \nV3 group (n=10)   \nC group (n=10)  \n \n \n6 weeks Surgical induced endometriosis \n(autograft model) \n \nV1 group: 0.5 mg (2mg/kg) vit C/1 mL \nwater for 6 weeks \nV2 group: 1.25 mg (5 mg/kg) vit C/1 mL \nwater for 6 weeks \nV3 group: 2.5 mg (10 mg/kg) vit C/1 mL \nwater for 6 weeks  \nC group: distillated water 1 mL for 6 weeks \n \nFinal surgical assessment \nVitamin C vs no \nvitamin C in all \ngroups \nImplant volume after opertaion (mm3)  \nWeight of cyst (mg) \nHistological cell scores  \nTrichrome fibrosis scores  \nNK cell contents  \n \n \n \n \nEshrat Kalehoei \net al., 2023 \n[13] \nTherapeutic effects of L-\narginine, L-carnitine, and \nmesenchymal stem cell-\nconditioned medium on \nendometriosis-induced \noocyte poor quality in an \nAdult female NMRI mice (6–\n8 weeks old). \n(n=not stated) \n \n 1. EMS induction  \n2. IVF  \n \n1. control  \n2. 250 mg/kg LA \n3. 250 mg/kg LC \n1. In vitro maturation of immature oocytes: \nGV (%) \n\nManuscript accepted for publication\n \n \nexperimental mouse \nmodel \n1. Normal group  \n2. EMS-induced group \nLA: 250 mg/kg  \nLC: 250 mg/kg LC \nBMSC-CM: 100 μL of CM/mouse \n \n4. 100 μL BMSC-\nCM \n \nGVBD (%)  \nMII (%)  \nDEG (%) \n \n2. Blastocysts cell number \nN. Blast  \nN. total cells  \nN. TE  \nN. ICM  \nTE/ICM \n \n3. The percentage of different steps of mice emb  \ndevelopment \nN. MII \nIVF (%)  \nCleavage (%) \nMorula (%)  \nBlastocyst (%) Degenerated (%) \n \n4. blood serum antioxidant capacity \nTAC (nmol/mL) \nNO (nmol/mL) \nTOS (nmol/mL) \nOSI \n \nAll these outcomes are assessed in both EMS a  \nnormal groups and according to different antioxi  \ntherapy (CO, LA, LC, BMSC-CM). \n \n\nManuscript accepted for publication\n \n \nHayedeh \nHoorsan et al., \n2022 \n[12] \nThe effectiveness of \nantioxidant therapy \n(vitamin C) in an \nexperimentally induced \nmouse model of ovarian \nendometriosis  \nMature, virgin female NMRI \nmice (n=14) \n \nA group (n=7)  \nB group (n=7)  \n \nNot stated Surgical induced endometriosis \n(autograft model) \n \n2\nnd surgery (assessment of the \nendometriotic implants) \n \nA group: 50 mg/kg (0.5 mL) vit C every 2 \ndays for 4 weeks \nB group: a 0.5 mL mix of water and starch \n \nFinal surgical assessment \n \n \nVitamin C vs no \nvitamin C \nin all groups \nImplant volume at the 2nd operation (mm3) \nImplant volume at the 3rd operation (mm3)  \nWeight 1 (initial) (g) \nWeight 2 (final) (g) \nHistological cell scores   \nTrichrome fibrosis scores  \nFollicle number  \nAtretic follicle number  \nCorpus luteum number \n \nAbbrevations: NK, natural killer; vit C, vitamin C, EMS, endometriosis; IVF, in vitro fertilization; LA, L-arginine; LC, L-carnitine; BMSC-CM, bone \nmorphogenetic stem cells GV: Germinal vesicle; GVBD: Germinal vesicle break down; MII, metaphase II; DEG: degenerate oocytes; GVBD: \nGerminal vesicle break down; TOS, total oxidant status; NO, nitric oxide; TAC, total antioxidant capacity; OSI, oxidative stress index; CO, \ncontrol. \n \n \n \n \n \n \n \n \n\nManuscript accepted for publication\n \n \nTable 2. Description of selected studies included in the review (patients - human) \nFirst \nauthor, \nyear of \npublication \nTitle  Population Follow up \nperiod  \nIntervention  Comparison Outcomes  \nVanessa \nS. I. et al., \n2015  \n[15] \nN-Acetyl-\nCysteine and L-\nCarnitine \nPrevent Meiotic \nOocyte Damage \nInduced by \nFollicular Fluid \nFrom Infertile \nWomen With \nMild \nEndometriosis \nFF samples from \ninfertile women \n(n=22) \n \n1. EMS-\nassociated \ninfertility (n=11) \n \n2. other infertility \n(n=11)  \n \n \n \nFebruary \n2009 - \nFebruary \n2011 \n1. Laparoscopic \nsurgery in women \nwith EMS. \n2. FF-collection  \n3. Bovine oocyte \ncollection  \n4. In Vitro Maturation \n \n1.NAC 1.5 mmol/L \n2. LC 0.6 mg/mL \n3.NAC 1.5 mmol/L + \nLC 0.6 mg/mL \n \n1. (No-FF) \n2. (CFF) \n3. (C + \nNAC 1.5 \nmmol/L) \n4. (C + LC \n0.6 mg/mL) \n5. (C + \n2Ao);  \n6. (EFF) \n7. (E + NAC \n1.5 mmol/L) \n8. (E + LC \n0.6 mg/mL)  \n9. (E + \n2Ao). \nMI, n (%) \nTI, n (%) \nPA, n (%) \nTotal no. of \nMII, n (%)  \nAnalyzable \nMII, n (%)  \nNormal MII, n \n(%) \nVanessa \nS. I. et al., \n2021 \n[16] \nFollicular Fluid \nfrom Infertile \nWomen with \nMild \nEndometriosis \nImpairs In Vitro \nBovine Embryo \nDevelopment: \nFF samples from \ninfertile women \n(n=22) \n \nFebruary \n2009 - \nFebruary \n2011\n \n1. Laparoscopic \nsurgery in women \nwith EMS. \n2. FF-collection  \n3. Bovine oocyte \ncollection  \n1. (No-FF) \n2. (CFF) \n3. (C + \nNAC 1.5 \nmmol/L) \nPresumptive \nzygotes (n) \nCleavage rate \n% (n) \n\nManuscript accepted for publication\n \n \nPotential Role of \nOxidative Stress \n1. EMS-\nassociated \ninfertility (n=11) \n \n2. other infertility \n(n=11)  \n \n4. In Vitro Maturation \n5. In Vitro \nFertilization \n6. n Vitro Embryo \nCulture \n \n1.NAC 1.5 mmol/L \n2.  LC 0.6 mg/mL \n3.NAC 1.5 mmol/L + \nLC 0.6 mg/mL \n \n4. (C + LC \n0.6 mg/mL) \n5. (C + \n2Ao);  \n6. (MEFF) \n7. (MEFF + \nNAC 1.5 \nmmol/L) \n8. (MEEF + \nLC 0.6 \nmg/mL)  \n9. (MEFF + \n2Ao). \nBlastocysts \nformation rate \n% (n) \nHatching rate \n% (n) \nXiang Lu \net al., \n2018  \n[14] \nEffects of \nvitamin C on the \noutcome of in \nvitro fertilization–\nembryo transfer \nin endometriosis: \nA randomized \ncontrolled study \nPatients with \nEMs (n=280) \n Group 1 \n– Vit C \ntreatment \n(n=160) \n Group 2 \n– no vit C \n(n=120) \nPatients with no \nEMs (n=150) \nJune 2013 \n-\nDecember \n2016.\n \n1. IVF-ET procedure \n2. Vit. C treatment  \n \nGroup 1 (n=160) \nreceived 1000 \nmg/day from 2 \nmonths before IVF-\nET treatment until 2 \nweeks after ET  \nEMS \npatients vs \nno EMS \npatients.  \n \nEMS \npatients \ntreated with \nvit C/ not \ntreated with \nvit C \n1. Laboratory \nand pregnancy \noutcomes in \nEMS patients/ \nno EMS \npatients \nTotal Gn \ndosage \nNo. of \nretrieved \noocytes \nFertilization \nrate (%) \nHigh-grade \nembryo rate \n(%) \n\nManuscript accepted for publication\n \n \nImplantation \nrate (%) \nClinical \npregnancy rate \n(%) \nNo. of frozen \nembryos \n \n2. Changes in \nserum levels \nof VitC and \noxidative \nstress markers \nin EMS \npatients with \nvit C/ no vit C \nSerum levels \nof VitC \n(μmol/L) \nSerum levels \nof SOD (U/L) \nSerum levels \nof \nTAC(mmol/L) \nSerum levels \nof MDA(μM) \nSerum levels \nof ROS(cps) \n \n\nManuscript accepted for publication\n \n \n \n \n Jennifer \nMier-\nCabrera et \nal., 2008 \n[17] \nEffect of \nvitamins C and E \nsupplementation \non peripheral \noxidative stress \nmarkers and \npregnancy rate \nin women with \nendometriosis \nPatients with \nEMs (n=34) \n \nGroup 1 – Vit C \nand Vit E \ntreatment (n=16) \n \nGroup 2 – \nplacebo (n=18) \n \n15 months Group 1 - 343 mg of \nvitamin C and 84 mg \nof vitamin E \n \nVit C and vit \nE patints \ngroup vs \nplacebo \ngroup \n1. Oxidative \nstress marker \nlevels in \nwomen with \nendometriosis \n((Baseline, at \n2 months, at 4 \nmonths, at 6 \nmonths in PF, \nplasma). \nLOOH \n(μmol/L)  \nMDA (μmol/L) \n \n2. Pregnancy \nrate  \nNalini \nSantanam \net al., \n2016 \n[18] \nMyeloperoxidase \nas a Potential \nTarget in \nWomen With \nEndometriosis \nUndergoing IV \nPatients (n=117) \nComplete data \n(n=68). \n \nNo EMs group \n(n=41) \nMild EMs group \n(n=20) \nNot stated  1. IVF  \n2. Collection of FF \n3. Collection of \nBlood Plasma \n \nPatients received \n800 IU of vit E and \n1000 IU of vit C for a \nminimum of 8 weeks: \n \nVit C and vit \nE patints \ngroup vs \nplacebo \ngroup \nMPO level \n(ng/ml) \n\nManuscript accepted for publication\n \n \nModerate/severe \nEMs group (n=7) \n \nNo EMs group vit \nC+E (n=5) \nMild EMs group vit \nC+E (n=5) \nModerate/severe \nEMs group vit C+E \n(n=4) \n \n \n \n \nSahar \nRostami et \nal., 2023  \n[20] \nAstaxanthin \nameliorates \ninflammation, \noxidative stress, \nand reproductive \noutcomes in \nendometriosis \npatients \nundergoing \nassisted \nreproduction: A \nrandomized, \ntriple-blind \nplacebo-\ncontrolled \nclinical trial \nInfertile patients \n(n=73) with \nEMs.  \n \nComplete data \n(n=50). \n \nAST group \n(n=25) \nPlacebo group \n(n=25) \n \nDecember \n2021 - \nSeptember \n2022. \n1. IVF  \n2. Blood and FF \ncollection \n \nAST group: 6 mg \ndaily of oral AST for \n12 weeks \nPlacebo group: 6 mg \ndaily of placebo \ncapsules for 12 \nweeks \nAST \ntreatment \nvs placebo \n1. OS markers \nand cytokine \nlevels \nMDA \nSOD \nCAT \nTAC \nL-1b \nIL-6 \nTNF-a \n \n2. ART \noutcomes \n\nManuscript accepted for publication\n \n \nNumber of \noocytes  \nGV  \nMI  \nMII  \nOocyte \nmaturity rate \n(MII %)  \nFertilized  \nFertilization \nrate (%)  \nNumber of \nfrozen \nembryos  \nHigh-quality \nembryos  \nFrozen \nembryos  \nNumber of \ntransferred \nembryos \n\nManuscript accepted for publication\n \n \nLeila \nAmini et \nal., 2021  \n[19] \nThe Effect of \nCombined \nVitamin C and \nVitamin E \nSupplementation \non Oxidative \nStress Markers \nin Women with \nEndometriosis: A \nRandomized, \nTriple-Blind \nPlacebo-\nControlled \nClinical Trial \nPatients with \nendometriosis \n(n=60) \n \nA group (n=30) \nB group (n=30) \n \nJune 2017 \n- \nNovember \n2017 \nA group: vitamin C \n1000 mg/day (2 \ntablets/500 mg) + \nvitamin E 800 IU/day \n(2 tablets/400 IU) for  \n8 weeks. \n \nB group (placebo \npills (mannitol and \nmagnesium stearate \npolyvinylpyrrolidone)) \nfor 8 weeks. \nVit C and vit \nE patints \ngroup vs \nplacebo \ngroup \n1. OS markers \nlevels \nMDA \nROS \nTAC \n \n2. VAS score \nof \ndysmenorrhea, \ndyspareunia \n \nAbbrevations: CFF, control follicular fluid; OS, oxidative stress; ROS, reactive oxygen species; LC, L-carnitine; NAC, N-Acetyl-Cysteine; BMSC-\nCM, bone morphogenetic stem cells; TOS, total oxidant status; NO, nitric oxide; TAC, total antioxidant capacity; OSI, oxidative stress index; \nIVF, In vitro fertilization; SOD, superoxide dismutase; MDA, malondialdehyde; FF, follicular fluid; EFF, endometriosis follicular fluid; CFF, control \nfollicular fluid; LOOH, lipid hydroperoxide; MPO, myeloperoxidase; AST, astaxanthin; ART, associated reproductive technology; CAT, catalase; \nTAR, Total antioxidant response; NK, Natural killer; EMS, endometriosis; TNF-a, Tumor necrosis factor; IL-1b, interleukin 1b; IL-6, interleukin 6; \nGV, germinal vesicle; MI, metaphase I. PA, spontaneous parthenogenetic activation; TI, telophase \n  \n \n \n \n \n \n \n \n\n \n \nFigure 1. PRISMA flow chart diagram. The effectiveness of antioxidant therapy in women with endometriosis. \n \n \nManuscript accepted for publication\n\n \n \nFigure 2. ROBINS-1 tool for non-randomized trials \n \nDomains: \nD1: Bias due to confounding. \nD2: Bias due to selection of participants. \nD3: Bias in classification of interventions. \nD4: Bias due to deviations from intended interventions. \nD5: Bias due to missing data. \nD6: Bias in measurement of outcomes. \nD7: Bias in selection of the reported result. \n \n \n \n \n \nManuscript accepted for publication\n\n \n \nFigure 3. RoB2 tool for randomized trials \n \nDomains: \nD1: Bias arising from the randomization process. \nD2: Bias due to deviations from intended intervention. \nD3: Bias due to missing outcome data. \nD4: Bias in measurement of the outcome. \nD5: Bias in selection of the reported result \nManuscript accepted for publication","source_license":"CC0","license_restricted":false}