Protective Effects And Mechanisms Of Curcumin On Dopaminergic Cells

Abstract objective to investigate the cytoprotection of curcumin against rotenone-induced injury and the molecular mechanisms underlying in PC12 cells.Methods:the insulted mode of PC 12 Cells was established with rotenone (Ro),cell viability was determined using MTT reduction assay;the content of reactive oxygen species(ROS) was detected with the method of DCFH-DA staining,chromatometry to detect the total activity of SOD;DCFH-DA staining to measure the level of intracellular ROS;flow cytometric analysis to survey the rate of cell apoptosisResults:0.1μmol/L-1.0μmol/L Curcumin significantly decreased the inhibitory rate of Rotenone on the growth of PC 12 cells for 24h; 0.1μmol/L-1.0μmol/L Curcumin significantly ameliorate the changes in the morphology of PC 12 cells;increased the activities of intracellular SOD;decreased the production of intracellular ROS and inhibited the apoptosis of PC 12 cells induced by Rotenone for 24h.Conclusion:Curcumin can resist rotenone-induced cytotoxicity probably by the mechanism of scavenging intracellular ROS and increasing the activity of antioxidase. Purpose to investigate the effect of Curcumin on aggregtion of alph-synuclein and its mechanism to resist the Rotenone-induced injury to PC 12 cells.Methods the cellular mode of parkinson's disease was established by adoption of rat pheochromocytoma strain PC12 cells and utilization of Rotenone to induce injury to them;Cell viability was assessed with MTT,Enzymatic activity of three hydrolases in proteasome was measured by detection of the fluorophore of various cleavaged synthetic fluorogenic peptides;The expression and aggregation of a-synuclein in PC12 cells was observed by Western blot and immunofluorescence respectively and cell apoptosis by flow cytometry.Results Cell viability and activity of proteasome of Rotenone group were decreased dramatically;The expression and aggregation of a-synuclein and cell apotosis of Rotenone group increased apparently.0.5μmol/L and 1.0μmol/L Curcumin allowed Cell viability and activity of proteasome of PC 12 cells to increase significantly after co-incubation of Curcumin-pretreated PC12 cells with Ro for 24h and the resistant role of 5.0μmol/L and 10μmol/L Curcumin on the injury of Ro-induced PC12 cells decreased apparantly.Conclusion low concentrion of Curcumin was able to induce the activity of proteasome and inhibit the expression and aggregation of a-synuclein in PC12 cells and thereby to alleviate the injury of Rotenone-induced PC 12 cells. Abstract:To explore the protective effects of curcumin on dopaminergic cells by inducing the expression of heat shock protein70(Hsp70), inhibiting anormal expression and aggregation of a-synuclein and promoting proteasome system to degrade abnomal a-synuclein.Methods:The cellular model for overexpressing a-synuclein was established by adoption of rat pheochromocytoma strain PC 12 cells treated with Rotenone.Cell viability was assessed with MTT,Enzymatic activity of three hydrolases in proteasome was measured by detection of the fluorophore of various cleavaged synthetic fluorogenic peptides;Western blot was used to dectect the expression of Hsp70 and a-synuclein;immunofluorescence to observe their expression andα-synuclein aggregation.Results:At Rotenone group,cell viability,activity of proteasome were decreased dramatically(P<0.01),the expression level of Hsp70 and a-synuclein were increased significantly(P<0.01).Pretreatment with 0.5μmol/L and 1.0μmol/L Curcumin allowed cell viability,activity of proteasome in PC12 cells to increase significantly after co-incubation with Rotenone for 24h campared with Rotenone group(P<0.01),the expression level of Hsp70 to incease significantly(P<0.05,P<0.01 respectively),and significantly reduce a-synuclein expression (P<0.05) and aggregation;The protection of 5.0μmol/L and 10μmol/L Curcumin against the injury of Ro-induced PC12 cells decreased apparantly. Cell viability, activity of three hydrolases in proteasome are not significantly different from those of Rotenone group (P>0.05).Conclusion low concentrion of Curcumin was able to induce higher expression of Hsp70 and the activity of proteasome and therefore inhibit the anormal expression and aggregation of a-synuclein in PC 12 cells and thereby to alleviate the injury of Rotenone-induced PC 12 cells. Objective:To explore the effects of microglia on the impairment of dopaminergic cells and the mechanisms of Curcumin's protective effects on them by inhibitting microglia activation.Methods:The cellular model of PD was established by adoption of rat pheochromocytoma strain PC12 cells treated with Rotenone,PC12 cells were treated with the medium from Curcumin-pretreated-BV-2 cells which were conditioned with Rotenone,and the blank control group was established.Cell viability was assessed with MTT;DCFH-DA staining was used to measure the level of intracellular ROS in BV-2 cells;flow cytometric analysis to survey the rate of cell apoptosis;Western blot was used to dectect the level of NADPH oxidase combining with membrane of BV-2 cell.Results:Compared with the control group,the level of ROS in Curcumin-pretreated-BV-2 cells groups was decreased(P<0.01);Cell viability of PC 12 cells treated with MCMC was increased and the rate of apoptosis of them was decreased(P<0.01).The cell viability and rate of apoptosis of PC12 cells treated only with 5nM Rotenone were not different with those of blank control group(P>0.05).The level of NADPH oxidase P47-phox-combined with BV-2 cellular membrane of BV-2 activated by Rotenone was increased significantly(P <0.01),and the pretreatment of BV-2 cells with Curcumin made the level of NADPH oxidase P47-phox-combined with BV-2 cellular membrane decline significantly(P< 0.05)Results:Microglia in which NADPH oxidase was activated by Rotenone impair dopaminergic cells by producing ROS.Curcumin protects dopaminergic cells by inhibitting activation of NADPH oxidase in microglia and decreasing the production of ROS.