Cyclophilin A Expression In Foam Cells Derived From Smooth Muscle Cells And Effect Of Amlodipine

PartⅠ. Change of Cyclophilin A Expression in Smooth Muscle Cells Induced by Ox-LDLAIM To observe the mRNA and protein expression of Cyclophilin A in smooth muscle cells induced by oxidized low density lipoprotein(ox-LDL)of different concentration and different time and to analyze the effect of Cyclophilin A on smooth muscle cells induced by ox-LDL.METHODS Rat aortic vascular smooth muscle cells isolated by enzyme digestion applicated generally in our own laboratory were treated with different concentration (0,20,40,80,160 mg/L)of ox-LDL for 72 hours. RT-polymerase chain reaction(RT-PCR)and Western blot analysis were used to detect the change of mRNA and protein expression of Cyclophilin A. Then 80 mg/L ox-LDL was chosen into smooth muscle cells for different tim(e0,24,48,72,96h). RT-PCR and Western blot analysis were also used to detect the change of mRNA and protein expression of Cyclophilin A respectively. Integrated with documents, we chose the cells were treated with 80mg/L ox-LDL for 0 and 72h. Oil Red O Dye experiment showed the lipid droplets in the cells of the two groups. High Performance Liquid Chromatography(HPLC) analysis was peformed the relative value of cellular cholesterol easter and total cholesterol.RESULTS With the increasing of the concentration of ox-LDL, the mRNA and protein expression of Cyclophilin A in the cells was significantly decreased in a concentration-dependent manner. When 80mg/L ox-LDL was treated with the cells for different time, the expression of Cyclophilin A was also significantly decreased in a time-dependent manner. P< 0.05,there was significant discrepancy. Oil Red O dye showed that there were a lot of lipid droplets accumulated in the smooth muscle cells induced by 80mg/L ox-LDL for 72 hours, the relative value of cellular cholesterol easter and total cholesterol detected by HPLC analysis was 57.9%(>50%). This kind of cells were consistent with the character of the foam cells.CONCLUSION Ox-LDL can suppress the expression of Cyclophilin A in the smooth muscle cells.PartⅡ. Function of Amlodipine on Cellular Cholesterol Accumulation in Foam Cells Derived from Smooth Muscle Cells Induced by Ox-LDL and on the Expression of Cyclophilin AAIM To study the function of Amlodipine of different concentration on cellular cholesterol accumulation in foam cells derived from smooth muscle cells induced by ox-LDL and on the expression of Cyclophilin A to explore the new antiatherosclerotic role of Amlodipine. METHODS Considering the result above-mentioned,we chose the concentration and time of ox-LDL treated to be 80 mg/L and 72h, at the same time, we constructed the model of foam cells derived from smooth muscle cells induced by ox-LDL.The experiment groups included 6 groups:control group, ox-LDL group, different concentration(0.1,1.0,10.0μM)of Amlodipine pretreated for 1h and treated with 80 mg/L ox-LDL for 72h group and Amlodipine(10.0μM) treated alone without ox-LDL group. Oil Red O Dye experiment showed the lipid droplets in the cells of each group. High Performance Liquid Chromatography(HPLC) analysis was peformed the content of cellular total cholesterol and cholesterol ester. RT-PCR and Western-blot analysis were used to detect the mRNA and protein expression of Cyclophilin A. Then the function of Amlodipine on cellular cholesterol accumulation in foam cells derived from smooth muscle cells induced by ox-LDL and on the expression of Cyclophilin A was analyzed to explore the new antiatherosclerotic role of Amlodipine.RESULTS Oil Red O dye showed that with the treatment of Amlodipine, the lipid droplets were greatly decreased in a concentration-dependent manner vs 80mg/L ox-LDL for 72 h group. HPLC analysis was peformed the content of cellular total cholesterol and cholesterol ester were both significantly increased with ox-LDL treatment but decreased after Amlodipine treatment. RT-PCR and Western-blot analysis showed that with ox-LDL and Amlodipine treatment, Cyclophilin A expression were greatly increased in a concentration-dependent manner.CONCLUSION Amlodipine can up-regulate the expression of Cyclophilin A, relieve the cellular cholesterol accumulation and delay the foam cells derived from smooth muscle cells induced by ox-LDL.