光控释活性氧响应的共载榄香烯和二氢卟吩e6脂质体的制备、表征及体外抗膀胱癌5637细胞活性研究OA

Objective Reactive oxygen species(ROS)-responsive co-loaded elemene(Ee)and chlorin e6(Ce6)liposomes(Ee-Ce6-L)were prepared,characterization of their physicochemical properties,and evaluated for their inhibitory effects on bladder cancer 5637 cells.Methods The synergistic ratio of elemene and Ce6(Ee+Ce6)was screened using the MTT assay.Ee-Ce6-L was prepared via the thin-film hydration method and characterized for morphology,particle size,encapsulation efficiency,drug loading capacity,stability,ROS generation capacity,and in vitro release rate.MTT assays evaluated the cytotoxicity of Ee-Ce6-L against 5637 cells.Annexin V-FITC/PI double staining was used to study the apoptotic effects of Ee-Ce6-L on cells.Fluorescence microscopy and a fluorometer were employed to examine its impact on ROS generation capacity and mitochondrial membrane potential(MMP).Western blotting analysis was conducted to investigate the expression of apoptosis pathway-related proteins.Results Ee+Ce6 exhibited synergistic effects across the 40:1 to 200:1 concentration range,with optimal synergy observed at 120:1;Ee-Ce6-L exhibited good stability and dispersibility.After irradiation with 660 nm laser,the particle size changed from(194.27±0.20)nm to(390.97±2.76)nm,and the ζ potential shifted from(-19.06±0.07)mV to(-6.30±0.34)mV.In vitro release experiments demonstrated that Ee-Ce6-L exhibits dual functions of sustained release and light-controlled drug release;the encapsulation efficiencies of elemene and Ce6 were(94.02±0.38)%and(96.95±0.70)%,respectively,while the drug loading capacities of Ee and Ce6 were(11.51±0.46)%and(2.32±0.01)%;Ee-Ce6-L exhibited strong singlet oxygen generation capacity;In vitro cell experiments demonstrated that Ee-Ce6-L promoted apoptosis in 5637 cells by increasing ROS production and reducing MMP,as well as by decreasing B-cell lymphoma-2(Bcl-2)protein expression while increasing Bcl-2-associated X protein(Bax),cleaved poly ADP-ribose polymerase(cleaved PARP),and cleaved cystein-asparate protease-3(cleaved Caspase-3)protein expression.Conclusion Ee-Ce6-L exhibits ROS-responsive release properties and synergistically inhibits 5637 cell proliferation and induces apoptosis through the combined effects of traditional Chinese medicine and phototherapy.