Preparation Of Schisandra B-polymeric Micelles And Its Protective Effect On Neural Cells SH-SY5Y

Object: The optimal preparation process of Schisandrin B polymer micelles was established and the method of determination of encapsulation efficiency was established.The protective effect of Schisandra chinensis polymer micelles on SH-SY5 Y of nerve cells and its mechanism were discussed.Method:(1)Preparation of Schisandra Ethylene polymer micelles and establishment of its encapsulation efficiency method: The preparation process of Schisandra chinensis micelles was optimized by orthogonal design,and the Schisandra B-type micelles were prepared by ultrasonic method through Zetasizer Nano series.Nanoparticle size analyzer and transmission electron microscope were used to detect the particle size,potential and morphology of Schisandra chinensis polymer micelles.The content of Schisandrin B in micelles was determined by high performance liquid chromatography and the encapsulation efficiency and drug loading were calculated.Tested by methodological investigation.(2)Protective effect of Schisandra chinensis polymer micelles on nerve cells SH-SY5 Y and its mechanism: The in vitro release ability of Sch B-PM was determined by high performance liquid chromatography.Cellular uptake experiments were observed by laser confocal microscopy and fluorescence inverted microscope.MTT assay was used to determine the effect of Sch B-PM on cell viability and cytotoxicity.Flow cytometry was used to detect intracellular ROS content and intracellular antioxidants and peroxide content by ROS,MDA,GSH and SOD kits.The apoptosis was measured.The expression levels of Bcl-2,Bax,Caspase3,Nrf2,HO-1,Keap1 and BDNF in SH-SY5 Y were detected by Western Blotting.The expression levels of Bcl-2,Bax,Caspase3,Nrf2,HO-1,Keap1 and BDNF genes in SH-SY5 Y were detected by RT-PCR.Result:(1)The best process is organic phase dichloromethane,mPEG-PLA 4mg,PLA4 mg,dichloromethane 2mL,water phase 1mL;the prepared micelles are regular spherical or spheroidal,the average micelle particle size is(90±0.95)nm The zeta potential was(-2.94±0.30)mV;the average encapsulation efficiency of Schisandra chinensis micelles was(51.17±0.02)%,and the average drug loading was(10.03±0.40)%.(2)The Sch B release in Sch B-PM was more than 48 hours,stable after 12 hours,and the cumulative release of Sch B was about 70%.The coumarin-6 fluorescence intensity was most pronounced after 4 h and 6 hof incubation.which means that SH-SY5 Y cells have the ability to internalize micelles.The 5?g/mL Sch B-PM group performed better than the other groups after H2O2-induced SH-SY5 Y cell pretreatment for 12 h.Both Sch B and Sch B-PM cleared ROS production,decreased MDA content(p <0.05),increased total GSH levels(p <0.05),and maintained intracellular SOD activity for 12 h at 5 ?g/mL(p < 0.05).In the apoptosis experiment,the total apoptosis rate of the blank control group was(3.40±0.13)%,the total apoptosis rate of the model group was(49.10±2.91)%,and the total apoptosis rate of Sch B group was(34.60±1.25)%.Sch B-PM The total apoptotic rate was(28.60±1.06)%.Compared with the blank control group,the total apoptosis rate of the model control group was significantly increased(P<0.01).Compared with the model group,the total apoptosis rate of Sch B and Sch B-PM groups.Significantly decreased(P<0.05,P<0.01).At the protein level,it was proved that Sch B and Sch B-PM can up-regulate the expression levels of Nrf2,HO-1,Bcl-2 and BDNF proteins in nerve cells(P<0.01),and down-regulate Keap1,Bax and Caspase-3proteins in nerve cells.The expression level(P<0.01).At the genetic level,it was proved that Sch B and Sch B-PM can up-regulate the expression levels of Nrf2,HO-1,Bcl-2 and BDNF genes in neurons(P<0.01),and down-regulate the Keap1,Bax and Caspase-3 genes in neurons.The expression level(P<0.01).Conclusion:(1)In this study,the preparation method and encapsulation efficiency of Schisandrin B polymer micelles were established.The results show that the method is accurate,simple and reliable,and can be used for drug content and encapsulation in Schisandra ethylene polymer micelles.The determination of the rate provides a theoretical basis for the future research of the new preparation of Schisandra B.(2)Sch B and Sch B-PM can up-regulate the expression levels of Nrf2,HO-1,Bcl-2 and BDNF protein genes and down-regulate Keap1,Bax and Caspase-3 by promoting the Nrf2/HO-1 signaling pathway.The expression of the protein gene inhibits oxidative damage and apoptosis of neuronal cells,and plays a protective role for neuronal cells.