{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:36:50Z","timestamp":1787027810166,"version":"build-2736575974"},"reference-count":47,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,19]],"date-time":"2022-12-19T00:00:00Z","timestamp":1671408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000968","name":"American Heart Association","doi-asserted-by":"publisher","award":["18CDA34080403"],"award-info":[{"award-number":["18CDA34080403"]}],"id":[{"id":"10.13039\/100000968","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000968","name":"American Heart Association","doi-asserted-by":"publisher","award":["P30EY004068"],"award-info":[{"award-number":["P30EY004068"]}],"id":[{"id":"10.13039\/100000968","id-type":"DOI","asserted-by":"publisher"}]},{"name":"WSU-grant boost (ASI)","award":["18CDA34080403"],"award-info":[{"award-number":["18CDA34080403"]}]},{"name":"WSU-grant boost (ASI)","award":["P30EY004068"],"award-info":[{"award-number":["P30EY004068"]}]},{"name":"Department of Ophthalmology, Visual and Anatomical Sciences (OVAS), Wayne State University","award":["18CDA34080403"],"award-info":[{"award-number":["18CDA34080403"]}]},{"name":"Department of Ophthalmology, Visual and Anatomical Sciences (OVAS), Wayne State University","award":["P30EY004068"],"award-info":[{"award-number":["P30EY004068"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Purpose: Mitochondrial dysfunction is central to breaking the barrier integrity of retinal endothelial cells (RECs) in various blinding eye diseases such as diabetic retinopathy and retinopathy of prematurity. Therefore, we aimed to investigate the role of different mitochondrial constituents, specifically those of oxidative phosphorylation (OxPhos), in maintaining the barrier function of RECs. Methods: Electric cell-substrate impedance sensing (ECIS) technology was used to assess in real time the role of different mitochondrial components in the total impedance (Z) of human RECs (HRECs) and its components: capacitance (C) and the total resistance (R). HRECs were treated with specific mitochondrial inhibitors that target different steps in OxPhos: rotenone for complex I, oligomycin for complex V (ATP synthase), and FCCP for uncoupling OxPhos. Furthermore, data were modeled to investigate the effects of these inhibitors on the three parameters that govern the total resistance of cells: Cell\u2013cell interactions (Rb), cell\u2013matrix interactions (\u03b1), and cell membrane permeability (Cm). Results: Rotenone (1 \u00b5M) produced the greatest reduction in Z, followed by FCCP (1 \u00b5M), whereas no reduction in Z was observed after oligomycin (1 \u00b5M) treatment. We then further deconvoluted the effects of these inhibitors on the Rb, \u03b1, and Cm parameters. Rotenone (1 \u00b5M) completely abolished the resistance contribution of Rb, as the Rb became zero immediately after the treatment. Secondly, FCCP (1 \u00b5M) eliminated the resistance contribution of Rb only after 2.5 h and increased Cm without a significant effect on \u03b1. Lastly, of all the inhibitors used, oligomycin had the lowest impact on Rb, as evidenced by the fact that this value became similar to that of the control group at the end of the experiment without noticeable effects on Cm or \u03b1. Conclusion: Our study demonstrates the differential roles of complex I, complex V, and OxPhos coupling in maintaining the barrier functionality of HRECs. We specifically showed that complex I is the most important component in regulating HREC barrier integrity. These observed differences are significant since they could serve as the basis for future pharmacological and gene expression studies aiming to improve the activity of complex I and thereby provide avenues for therapeutic modalities in endothelial-associated retinal diseases.<\/jats:p>","DOI":"10.3390\/cells11244128","type":"journal-article","created":{"date-parts":[[2022,12,19]],"date-time":"2022-12-19T07:27:30Z","timestamp":1671434850000},"page":"4128","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Relative Importance of Different Elements of Mitochondrial Oxidative Phosphorylation in Maintaining the Barrier Integrity of Retinal Endothelial Cells: Implications for Vascular-Associated Retinal Diseases"],"prefix":"10.3390","volume":"11","author":[{"given":"Shaimaa","family":"Eltanani","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thangal","family":"Yumnamcha","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Gregory","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9528-7483","authenticated-orcid":false,"given":"Mahmoud","family":"Elshal","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA"},{"name":"Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt"},{"name":"Department of Pharmacology, Wayne State University, Detroit, MI 48201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamed","family":"Shawky","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA"},{"name":"Department of Biochemistry, Faculty of Pharmacy, Horus University, New Damietta 34518, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8480-6252","authenticated-orcid":false,"given":"Ahmed S.","family":"Ibrahim","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Visual, and Anatomical Sciences, Wayne State University, Detroit, MI 48201, USA"},{"name":"Department of Pharmacology, Wayne State University, Detroit, MI 48201, USA"},{"name":"Department of Biochemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1171","DOI":"10.1161\/CIRCRESAHA.111.300233","article-title":"Mitochondria and endothelial function","volume":"112","author":"Kluge","year":"2013","journal-title":"Circ. 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