Preparation And Anti-Glioma Effect Of Nano-sized Liposomal Celastrol

Part one:Preparation of nano-sized Liposomal celastrol and distribution of nano-sized Liposomal celastrol in miceObjective:To prepare nano-sized liposomal Celastrol with high encapsulation efficiency and good stability,study the distribution of nano-sized Liposomal celastrol in mice.Methods:we obtained nano-sized liposomal celastrol by the thin film dispersed method.The RP-HPLC-UV analysis method of celastrol was studied and proved to be accurate and reliable for quantitative analysis in vitro through methodology investigation. Sephadex column chromatography was created to be an encapsulation efficiency determination method of nano-sized liposomal celastrol.Durg concentration in tissue of mice was determined by the method of LC-MS/MS.Result:The encapsulation efficiency was 71.67%,the particle size of the liposome was 128.1nm.Loading efficiency was 2.19%.Observation of TEM showed that nano-sized liposomal celastrol was round with smooth surfaces.Inner core was Celastrol,surrounding was phosphatides.C_max and AUC and MRT and t_1/2 of nano-sized liposomal celastrol was increased compared with active compound Celastrol.Target index in of nano-sized liposomal celastrol in lung and brain and heart was 3.54 and 2.79 and 2.66.Conclusion:Nano-sized liposomal may serve as availability carrier of Celastrol. Nano-sized liposomal Celastrol could increase blood concentration and half life. Nano-sized liposomal Celastrol had good targeting efficiency in brain and lung and heart. Part two:Nano-sized liposomal Celastrol on the inhibition of a human malignant glioma cell line SHG-44 in vivoObjective:To investigate antitumor effects of nano-sized liposomal Celastrol on the growth of a human malignant glioma cell line SHG-44 in vivo.To compare the toxic effect between nano-sized liposomal Celastrol and active compound of Celastrol.Methods:SRB colorimetric assay was used to evaluate antitumor effect on three glioma cell lines.Animal models were constructed on BALB/c nude mice with subcutaneously transplanted neoplasma of SHG-44 glioma.The nude mice bearing with SHG44 glioma were divided into six groups by random selection,which were treated with different doses of nano-sized liposomal Celastrol or active compound of Celastrol(4mg/kg,and 1mg/kg,every day for four weeks)or with Cisplatin(2 mg/kg,) or blank nanoliposomes.The dimension of xenografts was measured and the living state and weight of nude mice with SHG-44 glioma were observed.The concentration of Celastrol in xenografts was determined by liquid chromatography-trandem mass spectrometry.The parameters concerning heart,liver and kidney function were measured and the morphology of organ tissues was observed pathologically.Results:Nano-sized liposomal Celastrol and active compound Celastrol have the similar cytotoxicity in vitro assay.Nano-sized liposomal Celastrol and active compound Celastrol at 4mg/kg can inhibit the growth of xenografts in nude mice with SHG44 glioma (P＜0.05) compared with the control and the tumor volume was reduced by 68.4%and 66.5%.Nano-sized liposomal Celastrol at 1mg/kg can inhibit the growth of xenografts in nude mice with SHG44 glioma while active compound Celastrol at 1mg/kg cannot.Active compound Celastrol reduce the weight of nude mice with SHG-44 glioma while nano-sized liposomal Celastrol haven' the same the toxic effect.Conclusion:It is demonstrated that nano-sized liposomal Celastrol can achieved the same therapeutic effects with lower dosage.The side-effect of nano-sized liposomal Celastrol is less than the same dosage of active compound Celastrol.Nano-sized liposomal Celastrol had good targeting efficiency in xenograft,DTI was 2.51.