{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T07:25:45Z","timestamp":1778225145199,"version":"3.51.4"},"reference-count":53,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,5,17]],"date-time":"2020-05-17T00:00:00Z","timestamp":1589673600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["EY028773; EY019706; GM122744"],"award-info":[{"award-number":["EY028773; EY019706; GM122744"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"name":"International Retina Research Foundation","award":["International Retina Research Foundation"],"award-info":[{"award-number":["International Retina Research Foundation"]}]},{"name":"Carl Marshall &amp; Mildred Almen Reeves Foundation","award":["Carl Marshall & Mildred Almen Reeves Foundation"],"award-info":[{"award-number":["Carl Marshall & Mildred Almen Reeves Foundation"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The retinal pigment epithelium (RPE), the outermost layer of the retina, provides essential support to both the neural retina and choroid. Additionally, the RPE is highly active in modulating functions of immune cells such as microglia, which migrate to the subretinal compartment during aging and age-related degeneration. Recently, studies have highlighted the important roles of microRNA (miRNA) in the coordination of general tissue maintenance as well as in chronic inflammatory conditions. In this study, we analyzed the miRNA profiles in extracellular vesicles (EVs) released by the RPE, and identified and validated miRNA species whose expression levels showed age-dependent changes in the EVs. Using co-culture of RPE and retinal microglia, we further demonstrated that miR-21 was transferred between the two types of cells, and the increased miR-21 in microglia influenced the expression of genes downstream of the p53 pathway. These findings suggest that exosome-mediated miRNA transfer is a signaling mechanism that contributes to the regulation of microglia function in the aging retina.<\/jats:p>","DOI":"10.3390\/ijms21103541","type":"journal-article","created":{"date-parts":[[2020,5,18]],"date-time":"2020-05-18T02:43:42Z","timestamp":1589769822000},"page":"3541","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":45,"title":["Exosomal MiRNA Transfer between Retinal Microglia and RPE"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1049-2208","authenticated-orcid":false,"given":"Dorothea R.","family":"Morris","sequence":"first","affiliation":[{"name":"Department of Ophthalmology &amp; Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sarah E.","family":"Bounds","sequence":"additional","affiliation":[{"name":"Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huanhuan","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei-Qun","family":"Ding","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yan","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology &amp; Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA"},{"name":"Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0349-7636","authenticated-orcid":false,"given":"Yin","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Neurobiology and Anatomy, University of Texas Health Science Center at Houston, Houston, TX 77030, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4755-5452","authenticated-orcid":false,"given":"Jiyang","family":"Cai","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology &amp; Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA"},{"name":"Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1089\/ars.2009.2598","article-title":"Mitochondrial turnover and aging of long-lived postmitotic cells: The mitochondrial-lysosomal axis theory of aging","volume":"12","author":"Terman","year":"2010","journal-title":"Antioxid. 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