title: Effects of fenofibrate on adiponectin expression in retinas of streptozotocin-induced diabetic rats.
abstract: Adiponectin has been associated with increased risks of microvascular complications in diabetes; however, its role in the development of diabetic retinopathy (DR) is unknown. Fenofibrate is a lipid-lowering agent that has been shown to be capable of preventing DR progression. We investigated the expression of adiponectin and its receptors in DR and evaluated the effects of fenofibrate on their expression. The mRNA and protein levels of adiponectin and its receptors were elevated in retinas of streptozotocin-induced diabetic rats and were suppressed following fenofibrate treatment. Immunofluorescence staining demonstrated that adiponectin and adipoR1 were expressed in cells located within blood vessels, the retinal ganglion, and the inner nuclear layer. AdipoR1 was strongly expressed whereas adipoR2 was only weekly expressed in vascular endothelial cells. The in vitro experiments showed that adiponectin expression was induced by high glucose concentrations in RGC-5 and RAW264.7 cells and was suppressed following fenofibrate treatment. AdipoR1 and adipoR2 levels in RGC-5 cells were elevated in high glucose concentrations and suppressed by fenofibrate. Our results demonstrated that adiponectin may be a proinflammatory mediator in diabetic retinas and fenofibrate appears to modulate the expression of adiponectin and its receptors in diabetic retinas, effectively reducing DR progression.
authors.affiliation: Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan.
authors.forename: Ying-Jung
authors.initials: YJ
authors.lastname: Hsu
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei 100, Taiwan.
authors.forename: Lu-Chun
authors.initials: LC
authors.lastname: Wang
authors.affiliation: Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan ; Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan.
authors.forename: Wei-Shiung
authors.initials: WS
authors.lastname: Yang
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei 100, Taiwan.
authors.forename: Chung-May
authors.initials: CM
authors.lastname: Yang
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, College of Medicine, National Taiwan University, No. 7 Chung-Shan South Road, Taipei 100, Taiwan.
authors.forename: Chang-Hao
authors.initials: CH
authors.lastname: Yang
mesh_terms: D052242:Adiponectin / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001082:Aqueous Humor / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D002460:Cell Line; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000139:chemically induced / Q000188:drug therapy* / Q000235:genetics; D003930:Diabetic Retinopathy / Q000097:blood / Q000209:etiology / Q000235:genetics / Q000517:prevention & control*; D005260:Female; D011345:Fenofibrate / Q000494:pharmacology*; D018836:Inflammation Mediators / Q000378:metabolism*; D051379:Mice; D012333:RNA, Messenger / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D054419:Receptors, Adiponectin / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D012160:Retina / Q000187:drug effects* / Q000378:metabolism; D013311:Streptozocin
chemical_list: D052242:Adiponectin; C499920:Adipoq protein, rat; D000893:Anti-Inflammatory Agents; D001786:Blood Glucose; D018836:Inflammation Mediators; D012333:RNA, Messenger; D054419:Receptors, Adiponectin; C504339:adiponectin receptor 1, rat; C506573:adiponectin receptor 2, rat; D013311:Streptozocin; D011345:Fenofibrate