[Effect of ursolic acid on caspase-3 and PARP expression of human MCF-7 cells].

OBJECTIVE: To study the effect of ursolic acid (UA), apentacyclic triterpene acid, on MCF-7 cell apoptosis, and probable mechanism involved by detecting the expressions of caspase-3 and poly ADP-ribose polymerase(PARP) at protein level. METHOD: MCF-7 cells were cultured with different concentrations of UA. Growth inhibition of UA on MCF-7 cells was evaluated by MTT assay. Cell cycle and sub-G1 peak were performed by FCM. Morphologic changes of UA-treated cells were observed by light microscope. Apoptotic cells with condensed or fragmented nuclei were visualized by Ho 33258 staining by a fluorescence microscope (EX: U. V.). The protein expression of caspase-3 and PARP was analyzed by immunofluorescence cell staining (SABC-Cy3). RESULT: 24 hours after UA treatment, inhibition of MCF-7 cell growth was concentration-dependent. The IC50 value for UA was (22.6 +/- 3.0) micromo x L(-1). Cell cycle anaysis by FCM showed that 50 micromol x L(-1) of UA arrested MCF-7 cell cycle at G0 - G1 phase. Morphological changes of MCF-7 Cells exhibited many of the hallmark features of apoptosis, including chromatin clumps and aggregation and DNA fragmentation. UA increased caspase-3 protein expression. CONCLUSION: The results suggest that UA evokes MCF-7 cell apoptosis is correlation with the up-regulation of caspase-3. Our study indicated that UA might be a potential Chinese medical component for breast neoplasm.

Effects of simvastatin on activities of endogenous antioxidant enzymes and angiotensin-converting enzyme in rat myocardium with pressure-overload cardiac hypertrophy.

AIM: To investigate effects of simvastatin (Sim) on the activities of antioxidant enzymes and angiotensin-converting enzyme in rat myocardium with pressure-overload cardiac hypertrophy. METHODS: Left ventricular hypertrophy (LVH) was induced by partly constricting rat abdominal aorta between the left and right renal artery. Rats were given ig Sim 1.8 and 3.6 mg . kg-1 . d-1 for 8 weeks following 6 weeks aortic constriction. Activities of antioxidant enzymes and angiotensin-converting enzyme, and lipid peroxidation of left ventricular (LV) tissue were determined. RESULTS: Contents of angiotensin II and thiobarbituric acid reactive substances (TBARS), and activity of ACE in LVH group (n = 8) were increased by 163 %, 90 %, and 130 %, respectively (P < 0.01)compared with sham-operated group (n = 7), and were decreased by 30 %, 37 %, and 51 %, respectively (P < 0.01) in high dosage Sim treatment group (n = 9) compared with LVH group. Activities of catalase and glutathione peroxidase of LV tissue in LVH group were decreased by 29 % and 23 % (P < 0.01) compared with sham-operated group, and were increased by 32 % and 22 % (P < 0.01) in high dosage Sim treatment group compared with LVH group. Activity of Cu, Zn-superoxide dismutase (SOD) of LV tissue was increased by 33 % in LVH group compared with sham-operated group. Sim treatment did not significantly affect activity of Cu,Zn-SOD. CONCLUSION: Alteration of redox status in myocardium is associated with cardiac hypertrophy and inhibitory effects of Sim on cardiac hypertrophy in rats model might be linked to its antioxidant effects.