title: Intravitreal administration of dexamethasone-loaded PLGA-TPGS nanoparticles for the treatment of posterior segment diseases.
abstract: The purpose of this research was to investigate the possibility of dexamethasone (DEX)-loaded PLGA-TPGS nanoparticles (NPs) in rabbits after intravitreal administration for the treatment of posterior segment diseases. The DEX-loaded PLGA-TPGS NPs were fabricated and characterized in terms of surface morphology, particle size and size distribution, entrapment efficiency, and in vitro drug release. The animals were classified randomly into two groups: experimental group with thirty rabbits, and control group with eighteen rabbits. Rabbits in the experimental group received intravitreal injections of 0.1 mL of DEX-loaded PLGA-TPGS NPs suspension and the control rabbits received intravitreal injection of 0.1 mL DEX (20 g/L in saline). The DEX concentrations in plasma and the ocular tissues such as the cornea, aqueous humor, lens, iris, vitreous humor, and chorioretina were determined by HPLC. The DEX-loaded PLGA-TPGS nanoparticle suspension were transparent and maintained a sustained release of DEX for about 45 days in vitreous and provided relatively constant DEX levels for more than 30 days with a mean concentration of 3.93 mg/L. Based on the area-under-the-curve (AUC), the bioavailability of DEX in the experimental group was significantly higher than that in the control group administrated with regular DEX. These results suggest that intravitreal administration of DEX-loaded PL.3A-TPGS NPs leads to a sustained release of DEX with a high bioavailability, providing a basis for a novel approach to treat posterior segment diseases.
authors: Xili Hospital, Shenzhen, 518055, P R. China.
authors: Chenming
authors: C
authors: Yang
authors: Liqin
authors: L
authors: Jiang
authors: Sijiang
authors: S
authors: Bu
authors: Lihua
authors: L
authors: Zhang
authors: Xiaojun
authors: X
authors: Xie
authors: Qingguo
authors: Q
authors: Zeng
authors: Dunwan
authors: D
authors: Zhu
authors: Yi
authors: Y
authors: Zheng
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D003907:Dexamethasone / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D004058:Diffusion; D005128:Eye Diseases / Q000188:drug therapy / Q000378:metabolism; D058449:Intravitreal Injections / Q000379:methods; D019344:Lactic Acid / Q000737:chemistry*; D008422:Materials Testing; D008657:Metabolic Clearance Rate; D053769:Nanocapsules / Q000008:administration & dosage* / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D057972:Posterior Eye Segment / Q000378:metabolism*; D011817:Rabbits; D014018:Tissue Distribution; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000893:Anti-Inflammatory Agents; D053769:Nanocapsules; D014810:Vitamin E; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D011092:Polyethylene Glycols; D003907:Dexamethasone; C014225:tocophersolan