{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T01:33:21Z","timestamp":1787967201747,"version":"build-2784847793"},"reference-count":49,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,8]],"date-time":"2023-04-08T00:00:00Z","timestamp":1680912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Massachusetts Lions Eye Research Foundation","award":["EY025961"],"award-info":[{"award-number":["EY025961"]}]},{"name":"Palatin Technologies Inc.","award":["EY025961"],"award-info":[{"award-number":["EY025961"]}]},{"DOI":"10.13039\/100000053","name":"NIH\/NEI","doi-asserted-by":"publisher","award":["EY025961"],"award-info":[{"award-number":["EY025961"]}],"id":[{"id":"10.13039\/100000053","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The endogenous neuropeptide \u03b1-Melanocyte Stimulating Hormone (\u03b1-MSH) is a potent suppressor of inflammation and has an essential role in maintaining the normal anti-inflammatory microenvironment of the retina. While the therapeutic use of \u03b1-MSH peptide in uveitis and diabetic retinopathy models has been demonstrated, its short half-life and instability limit its use as a therapeutic drug. A comparable analog, PL-8331, which has a stronger affinity to melanocortin receptors, longer half-life, and, so far, is functionally identical to \u03b1-MSH, has the potential to deliver melanocortin-based therapy. We examined the effects of PL-8331 on two mouse models of retinal disease, Experimental Autoimmune Uveoretinitis (EAU) and Diabetic Retinopathy (DR). PL-8331 therapy applied to mice with EAU suppressed EAU and preserved retinal structures. In diabetic mice, PL-8331 enhanced the survival of retinal cells and suppressed VEGF production in the retina. In addition, retinal pigment epithelial cells (RPE) from PL-8331-treated diabetic mice retained normal anti-inflammatory activity. The results demonstrated that the pan-melanocortin receptor agonist PL-8331 is a potent therapeutic drug to suppress inflammation, prevent retinal degeneration, and preserve the normal anti-inflammatory activity of RPE.<\/jats:p>","DOI":"10.3390\/ijms24086928","type":"journal-article","created":{"date-parts":[[2023,4,10]],"date-time":"2023-04-10T03:49:29Z","timestamp":1681098569000},"page":"6928","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Stimulating the Melanocortin System in Uveitis and Diabetes Preserves the Structure and Anti-Inflammatory Activity of the Retina"],"prefix":"10.3390","volume":"24","author":[{"given":"Tat Fong","family":"Ng","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Boston University Chobanian and Avedisian School of Medicine, Boston, MA 02118, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0330-8591","authenticated-orcid":false,"given":"Andrew W.","family":"Taylor","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Boston University Chobanian and Avedisian School of Medicine, Boston, MA 02118, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1016\/j.tips.2015.07.007","article-title":"Resolution Pharmacology: Opportunities for Therapeutic Innovation in Inflammation","volume":"36","author":"Perretti","year":"2015","journal-title":"Trends Pharm. 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