Effect of matrine on PPAR-γ and caveolin-1 expressions in foam cells derived from monocytes

AIM: To study the effect of matrine on PPAR-γ and caveolin-1 expressions and cholesterol ester (CE) in foam cells derived from monocytes. METHODS: The accumulation of cholesterol in monocytes was measured by fluorescence spectrophotometric method. The lipid peroxide within cells was detected by TBARS method; the foam cells were observed by oil red O staining. PPAR-γ mRNA and PPAR-γ, caveolin-1 levels were determined by RT-PCR and Western blot respectively. RESULTS: In the monocytes incubated with PMA and oxy-low density lipoprotein (ox-LDL), CE and lipid peroxide (MDA) increased from (3.4±0.6) mg/L, and (0.43±0.07) nmol/L to (64.8±6.8) mg/L and (8.50±1.23) nmol/L (P0.05) respectively, and foam cells increased from (4.7±2.2)% to (77.8±7.0)% (P0.05). In low, middle, high-dose matrine groups the contents of CE and MDA were (29.7±4.9) mg/L and (1.92±0.46) nmol/L, (5.8±1.3) mg/L and (0.6±0.08) nmol/L, (3.4±0.6) mg/L and (0.43±0.07) nmol/L respectively; and the foam cells accounted for (46.2±5.8)%, (16.3±3.4)%, and (4.8±1.5)% respectively, the levels of PPAR-γ mRNA and PPAR-γ, caveolin-1 protein were (6.4±2.2), (0.6±0.08), (0.5±0.09), (7.4±2.2), (0.6±0.08), (0.6±0.07), (8.6±2.7), (0.6±0.06), (0.7±0.06) respectively. The above changes were alleviated in the matrine treatment groups and the differences were significant between the matrine treatment and the ox-LDL+PMA groups (P0.05). CONCLUSION: The mechanism of anti-artherosclerosis by matrine may be related to its roles in reducing cholesterol accumulation and increasing the expression level of PPAR-γ and caveolin-1 in foam cells derived from monocytes.