title: Evaluations of therapeutic efficacy of intravitreal injected polylactic-glycolic acid microspheres loaded with triamcinolone acetonide on a rabbit model of uveitis.
abstract: Conventional treatments of uveitis are not ideal because of the short period of therapeutic efficacy. In the present study, biodegradable polylactic-glycolic acid microspheres loaded with triamcinolone acetonide (TA) were prepared to achieve sustained drug release and their therapeutic efficacy was investigated on a rabbit model of uveitis. TA-loaded microspheres (TA-MS) were prepared by the solvent evaporation method and characterized for encapsulation efficiency, particle size, morphology and in vitro release. The therapeutic efficacy was studied on the rabbit experimental uveitis model based on scoring of the inflammation, aqueous leukocyte counting, aqueous protein determination and histological examination. The TA-MS exhibited smooth and intact surfaces with an average diameter of 50.87 μm. The drug-loading coefficient and encapsulation efficiency were 15.2 ± 0.6 % and 91.24 ± 3.77 %, respectively. The drug release from TA-MS lasted up to 87 days, but only 46 days for TA suspension. The change in surface morphology also showed sustained drug release from TA-MS. TA-MS exhibited improved therapeutic efficacy in lipopolysaccharide -induced uveitis compared to TA suspension, especially in regard to the inhibition of inflammation. The TA-MS had a longer-term therapeutic effect on intraocular inflammation in LPS-induced uveitis in rabbits compared to TA suspension. The results suggested that TA-MS can be developed as a potential sustained-release system for the treatment of uveitis.
authors.affiliation: Department of Ophthalmology, Peking University Third Hospital, Beijing, 100191, People's Republic of China.
authors.forename: Wenchang
authors.initials: W
authors.lastname: Li
authors.forename: Bing
authors.initials: B
authors.lastname: He
authors.forename: Wenbing
authors.initials: W
authors.lastname: Dai
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Yuling
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D004195:Disease Models, Animal; D004337:Drug Carriers / Q000008:administration & dosage*; D006016:Glycolates; D058449:Intravitreal Injections; D019344:Lactic Acid; D008863:Microspheres; D011091:Polyesters; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011817:Rabbits; D014222:Triamcinolone Acetonide / Q000008:administration & dosage*; D014605:Uveitis / Q000188:drug therapy* / Q000473:pathology
chemical_list: D000893:Anti-Inflammatory Agents; D004337:Drug Carriers; D006016:Glycolates; D011091:Polyesters; D011108:Polymers; C031149:glycolic acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C033616:poly(lactide); D014222:Triamcinolone Acetonide