Recombinant Adiponectin Peptide Ameliorates Cortical Neuron Damage Induced by Chronic Cerebral Hypoperfusion by Inhibiting NF-κB Signaling and Regulating Microglial Polarization

Recombinant Adiponectin Peptide Ameliorates Cortical Neuron Damage Induced by Chronic Cerebral Hypoperfusion by Inhibiting NF-κB Signaling and Regulating Microglial Polarization | 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 Recombinant Adiponectin Peptide Ameliorates Cortical Neuron Damage Induced by Chronic Cerebral Hypoperfusion by Inhibiting NF-κB Signaling and Regulating Microglial Polarization li'an Huang, Wenxian Li, Di Wei, Zheng Zhu, Shuqin Zhan, Ru Zhang, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-137422/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Chronic cerebral hypoperfusion (CCH) is common in multiple central nervous system diseases that are associated with neuronal death and cognitive impairment. Microglial activation-mediated polarization changes may be involved in CCH-induced neuronal damage. Adiponectin (APN) is a fat-derived plasma protein that affects neuroprotection. This study investigated whether a recombinant APN peptide (APN-P) improved the cognitive function of CCH rats by regulating microglial polarization in the cortex. Methods A CCH rat model was established through bilateral common carotid artery occlusion (BCCAO) surgery. An antibody microarray was used to analyze differentially expressed proteins in the cerebral cortex of CCH rats compared to the sham rats. APN-P and a solvent control were used to intervene at different time points. Western blotting and immunofluorescence staining were conducted to examine the status of microglial polarization in different treatment groups. qRT-PCR was used to detect the expression levels of inflammatory and anti-inflammatory genes. Neuronal morphology was assessed via Nissl staining, and cognitive function was assessed with the Morris water maze test. In vitro , by inhibiting the expression of NF-κB in BV2 microglia and using Transwell co-culture systems of BV2 microglia and neurons, the effects of APN-P on neuroprotection and the underlying mechanism were investigated. Results In the cortical microglia of 12-week-old CCH rats, the expression of APN protein was significantly downregulated compared to the sham rats. CCH damages neurons and activates cortical microglial polarization to an M1-type by upregulating inflammatory factors. APN-P supplementation upregulated APN expression in cortical microglia, with neuronal survival as well as microglial polarization from an M1 toward an M2 phenotype in CCH cortex. In vivo and in vitro experiments revealed that APN-P promoted the expression of anti-inflammatory factors and neuronal survival by inhibiting NF-κB signaling, thus improving the cognitive function in CCH rats. Conclusions Our study revealed a novel mechanism by which APN-P suppresses the NF-κB pathway and promotes microglial polarization from M1 toward the M2-type to reduce neuron damage in the cortex after CCH. Neurobiology of Disease Chronic cerebral hypoperfusion Adiponectin microglial polarization neuron damage NF-κB Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Full Text Due to technical limitations, full-text HTML conversion of this manuscript could not be completed. However, the latest manuscript can be downloaded and accessed as a PDF. Supplementary Files Additionalfile1TableS1.docx Additional file 1 Table S1. Animal groups and number of rats used in the research. The number of rats in each group for each test were shown in the Table. Additionalfile2FigureS1.tif Additional file 2 Figure S1. Full gels of APN, iNOS, Arg-1, NF-κB, p-NF-κB and β-actin in vivo and in vitro. Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-137422","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research","associatedPublications":[],"authors":[{"id":7197682,"identity":"54657566-3734-4e0b-9850-16115018ddf5","order_by":0,"name":"li'an Huang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8UlEQVRIiWNgGAWjYBACAzBZIMHAwMx+4MCHCgk5fuK0GAC1sPMkPpxxxsJYsoE4LUDMz2BszNlWkbiBkBZzieRnD78YWMibMzOkSTPOk2DcwMD88NENPFosZ6SZG8sYSBjubGY8Jl24TYLZnIHN2DgHn8NuJJhJSxgADT8MtGXmNgk2ywYeNmn8WtK/gbTYA7WYSfPOkeAxOEBQS46Z5AcDiUSgFmNj3gYJCcJazrwpkwYGcvKGw6BAPiZhINlMyC/H07dJ/qios91w/jgwKmvq6vvZmx8+xqcFBJh5ULkElIMA4w8iFI2CUTAKRsEIBgA72UhHuwzsUwAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0002-0416-7532","institution":"Jinan University First Affiliated Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"li'an","middleName":"","lastName":"Huang","suffix":""},{"id":7197683,"identity":"9f7b946b-e260-4a37-8f47-921b9cddcf4f","order_by":1,"name":"Wenxian Li","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Wenxian","middleName":"","lastName":"Li","suffix":""},{"id":7197684,"identity":"fa60bb5d-6242-449b-a9b3-320da1e6f676","order_by":2,"name":"Di Wei","email":"","orcid":"","institution":"The Fourth Military Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Di","middleName":"","lastName":"Wei","suffix":""},{"id":7197685,"identity":"0dc6cd62-f2e4-4314-8013-e865d673a087","order_by":3,"name":"Zheng Zhu","email":"","orcid":"","institution":"University of California Davis","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zheng","middleName":"","lastName":"Zhu","suffix":""},{"id":7197686,"identity":"4ecd57cb-3223-4c85-9d80-e1eb440a73c0","order_by":4,"name":"Shuqin Zhan","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shuqin","middleName":"","lastName":"Zhan","suffix":""},{"id":7197687,"identity":"b60bc3f6-3b2e-46a9-85aa-337f43727256","order_by":5,"name":"Ru Zhang","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Ru","middleName":"","lastName":"Zhang","suffix":""},{"id":7197688,"identity":"ed9ec7e7-12db-4beb-9860-1535820cd2fb","order_by":6,"name":"Huqing Wang","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Huqing","middleName":"","lastName":"Wang","suffix":""},{"id":7197689,"identity":"50051f81-4b4b-4c4a-9ec4-3a16946b7aa1","order_by":7,"name":"Guilian Zhang","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Guilian","middleName":"","lastName":"Zhang","suffix":""}],"badges":[],"createdAt":"2020-12-28 22:57:05","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-137422/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-137422/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":4643816,"identity":"049d94a5-9329-4fcd-8ca8-6194ccbc1167","added_by":"auto","created_at":"2021-01-01 00:10:51","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":304643,"visible":true,"origin":"","legend":"Microglial activation and decreased expression of APN in the cortex of CCH rats. \na. A flowchart of the animal experiments. \nb. Representative images of Iba-1+ and NeuN+ cells in the cortexes of sham and CCH rats at the 2nd, 4th, 8th, and 12th week after BCCAO surgery. Magnification ×20, scale bar = 100 μm. \nc. Quantification of the Iba-1+ cells in the cortex region of rats in different groups. \nd. There was a negative correlation between the Iba-1+ and NeuN+ cell numbers. Values are mean ± SD, n = 3 slices from 4 animals per group, *P \u003c 0.05, **P \u003c 0.01 vs sham group, Student’s t test and Pearson correlation analysis. ROI, 200μm2. \ne. A heat map representation of the protein level analysis of antibody arrays that show that APN was the most statistically significant among 10 proteins in the cortex of CCH 12w rats compared to the sham (fold change = -4.23, P \u003c 0.05; n = 6 animals per group). \nf. Representative images of APN expression in Iba-1+ cells in the cortex region of sham and CCH rats at the 12th week after BCCAO surgery. Magnification ×60, scale bar = 30 μm. \ng. Quantification of the ratio of APN in Iba-1+ cells in cortex region. Values are mean ± SD, n = 3 slices from 3 animals per group, **P \u003c 0.01 vs sham group, Student’s t test. ROI, 100μm2. ","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/f45b47b763b3e2232daeb648.png"},{"id":4643669,"identity":"32e4eb98-6a66-4ea3-84ba-57d567b3ae71","added_by":"auto","created_at":"2021-01-01 00:04:51","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":295408,"visible":true,"origin":"","legend":"CCH polarizes microglia toward M1 phenotypes, while APN-P promotes M2 phenotypes in the rat cortex \na. The amino acid sequence of APN-P [23]. \nb, c. Western blotting analysis of the relative protein levels of APN, iNOS, and Arg-1 expressed in \nvivo. \nd. Representative images of CD16 expression in Iba-1+ cells in the cortex of sham, CCH, and CCH rats with APN-P treatment groups. Magnification ×60, scale bar = 30 μm. \ne. Representative images of CD206 expression in Iba-1+ cells in cortex of sham, CCH and, CCH with APN-P treatment groups. Magnification ×60, scale bar = 30 μm. \nf. Quantification of the Iba-1+ cell number in the cortex of different treatment groups. \ng. Quantification of CD16 in Iba-1+ cells (%) in the cortex of different treatment groups. \nh. Quantification of CD206 in Iba-1+ cells (%) in the cortex of different groups. \ni. Quantification of the CD16/CD206 ratio in the cortex of different treatment groups. \nj. Quantification of the CD206/CD16 ratio in the cortex of different treatment groups. \nValues are mean ± SD, n = 3 slices from 3 animals per group, **P \u003c 0.01 CCH vs sham groups, ##P \n\u003c 0.01 CCH+APN-P vs CCH groups, One way ANOVA test, Tukey tests. ROI, 100μm2.","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/7fd8312b69fdf422df0b7b29.png"},{"id":4643774,"identity":"e6568b17-78b4-49ad-8e64-d1f97db571ac","added_by":"auto","created_at":"2021-01-01 00:07:52","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":114037,"visible":true,"origin":"","legend":"CCH induces inflammatory responses, while APN-P treatment induces anti-inflammatory responses in the rat cortex the mRNA expression of (a) iNOS, (b) IL-6, (c) IL-18, (d) IL-1β, (e) TNF-α, (f) Arg-1, (g) IL-10, and (h) TGF-β in the cortex of rats in different groups. Values are mean ± SD, n = 6 animals per group, **P \u003c 0.01 CCH vs sham groups, ##P \u003c 0.01 CCH+APN-P vs CCH groups, One way ANOVA test, Tukey tests. ","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/f2db57cedd56bcd76f19cb9b.png"},{"id":4643770,"identity":"7a4a5f32-266f-4a2e-b291-61ab2ea0e067","added_by":"auto","created_at":"2021-01-01 00:07:51","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":292216,"visible":true,"origin":"","legend":"APN-P promotes the microglia M2 phenotype in LPS-induced BV2 cells Representative immunofluorescent images of (a) CD16 and (b) CD206 expression in Iba-1+ cells in BV2 cells from control, LPS, and LPS+APN-P treatment groups. Magnification ×60, scale bar = 30 μm. Quantification of (c) CD16 in Iba-1+ cells (%), (d) CD206 in Iba-1+ cells (%), (e) CD16/CD206 ratio, and (f) CD206/CD16 ratio in BV2 cells of different groups. Values are mean ± SD, n = 3 slices from 3 animals per group, **P \u003c 0.01 LPS vs control group, ##P \u003c 0.01 vs LPS group, One way ANOVA test, Tukey tests. ROI, 100μm2. ","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/9df457a3be0973857f98b0ee.png"},{"id":4643772,"identity":"365e2759-27a1-40a1-9062-bae7f38187e6","added_by":"auto","created_at":"2021-01-01 00:07:51","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":110712,"visible":true,"origin":"","legend":"APN-P promotes the microglial M2 phenotype and anti-inflammatory responses via NF-κB pathway inhibition \na. Western blotting analysis of in vivo NF-κB and p-NF-κB protein expression. b. Quantification of the in vivo p-NF-κB/NF-κB ratio. Values are mean ± SD, n = 3 samples per group, **P＜0.01 CCH vs sham group, ##P＜0.01 \nCCH+APN-P vs CCH group, One way ANOVA test, Tukey tests. c. Western blotting analysis of the protein expression of NF-κB, p-NF-κB, iNOS and Arg-1 in vivo. d. Quantification of the in vitro p-NF-κB/NF-κB ratio relative to iNOS and Arg-1 expression levels in control, LPS treatment, LPS + BAY and LPS + APN-P treated groups. Values are mean ± SD, n = 3 samples per group, *P \u003c 0.05, **P＜0.01 LPS vs control group, #P \u003c 0.05, ##P＜0.01 vs LPS group, One way ANOVA test, Tukey tests. The mRNA expression of (e) iNOS, (f) IL-6, (g) IL-18, (h) IL-1β, (i) TNF-α, (j) Arg-1, (k) IL-10, and (m) TGF-β in BV2 cells in different groups. Values are mean ± SD, n = 6 samples per group, **P＜0.01 LPS vs control group, ##P＜0.01 vs LPS group, One way ANOVA test, Tukey tests.","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/592ee7d6f2d6ce63e864f559.png"},{"id":4643674,"identity":"b8ab086c-7122-4341-94a4-74bb5cbba209","added_by":"auto","created_at":"2021-01-01 00:04:51","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":177318,"visible":true,"origin":"","legend":"Effects of APN-P on neuron protection a. Sections of the cortex and the hippocampal CA1 region were obtained and treated with Nissl staining. Magnification ×40, scale bar = 50 μm. b. Quantitative analysis of neuronal damage of the cortex region. c. Quantitative analysis of neuronal damage of the hippocampal CA1 region. Values are mean ± SD, n = 3 samples per group, **P＜0.01 CCH vs sham group, ##P＜0.01 CCH+APN-P vs CCH group, One way ANOVA test, Tukey tests. ROI, 200μm2. d. Flowchart of in vitro experiments (a microglia-neuron co-culture system). e. Quantitative analysis of neuronal viability of BV2 cells from different groups after co-culturing using a CCK-8 test. Values are mean ± SD, n = 5 samples per group, **P＜0.01 LPS vs control group, ##P＜0.01 vs LPS group, One way ANOVA test, Tukey tests. f. Representative images of CMFDA-labeled neurons (green) after co-culturing with different BV2 cells. Magnification ×40, scale bar = 100 μm. g. The quantification of the CMFDA fluorescence intensity in different groups. \nValues are mean ± SD, n = 3 samples per group, **P＜0.01 LPS vs control group, ##P＜0.01 vs \nLPS group, One way ANOVA test, Tukey tests. ","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/7c3c920ba4cf763492953515.png"},{"id":4643773,"identity":"a544544f-aa75-442c-9539-552be6b18623","added_by":"auto","created_at":"2021-01-01 00:07:52","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":93654,"visible":true,"origin":"","legend":"CCH exacerbates cognitive deficits, while APN-P improved cognitive function in rats a. EL of rats trained in a Morris water maze (day 1 to day 5). Values are mean ± SD, n = 6 samples per group, **P \u003c 0.01 CCH 4w vs sham group, ##P \u003c 0.01CCH 4w + APN-P vs CCH 4w group; **’P \u003c 0.01 CCH 8w vs sham group, ##’P \u003c 0.01 CCH 8w + APN-P vs CCH 8w group; **’’P \u003c 0.01 CCH 12w vs sham group, ##’’P \u003c 0.01 CCH 12w + APN- P vs CCH 12w group, Two-way ANOVA, Bonferroni post hoc test. b. Number of platform location crosses indicating that the CCH and CCH+APN-P treatment groups were significantly different from each other on day 6. c. Stay time of each treatment group on the platform during a single 60-s probe trial (day 6). Values are mean ± SD, n = 6 samples per group, **P \u003c 0.01 CCH vs sham group, ##P \u003c 0.01 CCH + APN-P vs CCH group, Two-way ANOVA, Bonferroni post hoc test. d. Representative images of the number of platform location crosses of each treatment group in the Morris water maze. ","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/76d3c63ebe6948ccbfb943d5.png"},{"id":4643677,"identity":"6cf29c01-3367-4a23-9bd9-8af8985c83c1","added_by":"auto","created_at":"2021-01-01 00:04:52","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":65498,"visible":true,"origin":"","legend":"Graphical abstract APN-P inhibited the NF-κB pathway and regulated microglial polarization from an M1 toward an M2 phenotype, which alleviated the inflammatory response and cortical neural injury, rescuing CCH-induced cognitive impairment.","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/6022762d14e1662cc5ac0054.png"},{"id":13570709,"identity":"ddb6fa7e-b520-4a90-9792-6628bba1449c","added_by":"auto","created_at":"2021-09-17 03:44:48","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":909042,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript4.pdf","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1_covered.pdf"},{"id":4643896,"identity":"5f0063ac-31cc-43fd-be84-4ceb472adf84","added_by":"auto","created_at":"2021-01-01 00:13:55","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":861797,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript4.pdf","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1_stamped.pdf"},{"id":4643769,"identity":"633e0f9f-111e-47ce-8e1b-c8f36bdfae33","added_by":"auto","created_at":"2021-01-01 00:07:51","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":21115,"visible":true,"origin":"","legend":"Additional file 1 Table S1. Animal groups and number of rats used in the research. The number of rats in each group for each test were shown in the Table. ","description":"","filename":"Additionalfile1TableS1.docx","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/ba921c6333099ad142b6b9a4.docx"},{"id":4643678,"identity":"45c44610-a674-4b93-99f0-d1e161e0b656","added_by":"auto","created_at":"2021-01-01 00:04:52","extension":"tif","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":1505392,"visible":true,"origin":"","legend":"Additional file 2 \nFigure S1. Full gels of APN, iNOS, Arg-1, NF-κB, p-NF-κB and β-actin in vivo and in vitro. ","description":"","filename":"Additionalfile2FigureS1.tif","url":"https://assets-eu.researchsquare.com/files/rs-137422/v1/4ae94f7d0c8327d2f1957349.tif"}],"financialInterests":"","formattedTitle":"\u003cp\u003eRecombinant Adiponectin Peptide Ameliorates Cortical Neuron Damage Induced by Chronic Cerebral Hypoperfusion by Inhibiting NF-κB Signaling and Regulating Microglial Polarization\u003c/p\u003e","fulltext":[{"header":"Full Text","content":"Due to technical limitations, full-text HTML conversion of this manuscript could not be completed. However, the latest manuscript can be downloaded and \u003ca href='/article/rs-137422/latest.pdf' target='_blank'\u003e accessed as a PDF.\u003c/a\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Chronic cerebral hypoperfusion, Adiponectin, microglial polarization, neuron damage, NF-κB ","lastPublishedDoi":"10.21203/rs.3.rs-137422/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-137422/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e Chronic cerebral hypoperfusion (CCH) is common in multiple central nervous system diseases that are associated with neuronal death and cognitive impairment. Microglial activation-mediated polarization changes may be involved in CCH-induced neuronal damage. Adiponectin (APN) is a fat-derived plasma protein that affects neuroprotection. This study investigated whether a recombinant APN peptide (APN-P) improved the cognitive function of CCH rats by regulating microglial polarization in the cortex. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e A CCH rat model was established through bilateral common carotid artery occlusion (BCCAO) surgery. An antibody microarray was used to analyze differentially expressed proteins in the cerebral cortex of CCH rats compared to the sham rats. APN-P and a solvent control were used to intervene at different time points. Western blotting and immunofluorescence staining were conducted to examine the status of microglial polarization in different treatment groups. qRT-PCR was used to detect the expression levels of inflammatory and anti-inflammatory genes. Neuronal morphology was assessed via Nissl staining, and cognitive function was assessed with the Morris water maze test. In vitro , by inhibiting the expression of NF-κB in BV2 microglia and using Transwell co-culture systems of BV2 microglia and neurons, the effects of APN-P on neuroprotection and the underlying mechanism were investigated. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e In the cortical microglia of 12-week-old CCH rats, the expression of APN protein was significantly downregulated compared to the sham rats. CCH damages neurons and activates cortical microglial polarization to an M1-type by upregulating inflammatory factors. APN-P supplementation upregulated APN expression in cortical microglia, with neuronal survival as well as microglial polarization from an M1 toward an M2 phenotype in CCH cortex. In vivo and in vitro experiments revealed that APN-P promoted the expression of anti-inflammatory factors and neuronal survival by inhibiting NF-κB signaling, thus improving the cognitive function in CCH rats. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e Our study revealed a novel mechanism by which APN-P suppresses the NF-κB pathway and promotes microglial polarization from M1 toward the M2-type to reduce neuron damage in the cortex after CCH.\u003c/p\u003e","manuscriptTitle":"Recombinant Adiponectin Peptide Ameliorates Cortical Neuron Damage Induced by Chronic Cerebral Hypoperfusion by Inhibiting NF-κB Signaling and Regulating Microglial Polarization","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2021-01-01 00:04:49","doi":"10.21203/rs.3.rs-137422/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f9c1036a-d010-4abc-b491-5a875ca52d81","owner":[],"postedDate":"January 1st, 2021","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":1677657,"name":"Neurobiology of Disease"}],"tags":[],"updatedAt":"2021-01-12T13:24:26+00:00","versionOfRecord":[],"versionCreatedAt":"2021-01-01 00:04:49","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-137422","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-137422","identity":"rs-137422","version":["v1"]},"buildId":"cBFmMYwuxLRRLfASyISRj","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}