RESUMO
Objective: To explore the effect of oxidative stress injury on the mechanism of vascular smooth muscle cell (VSMC) calciifcation induced by calcium and phosphorus in experimental rats. Methods: The VSMC calcification was induced by incubating the cells with calcium chloride (CaCl2) andβ-sodium glycerophosphate (β-GP) for 8 days, and the cells were divided into 4 groups: ① Control group, ② Calcification group,③ Calciifcation+H2O2 group, ④ Calciifcation+catalase group. The calcium nodule formation and calcium deposition in VSMC were detected by Alizarin red staining and o-cresolphthalein complexone method, the reactive oxygen species (ROS) was detected by DCFH-DA probe staining and the protein expression of Runx2 was examined by Western blot analysis. Results: Compared with Control group, Calciifcation group showed the higher ROS production, more calcium nodule and calcium deposition, higher Runx2 protein expression;while compared with Calciifcation group, the above indexes were even higher in Calciifcation+H2O2 group, P0.05. Conclusion: CaCl2 andβ-GP treatment may induce VSMC calciifcation via activating ROS-Runx2 signal pathway in experimental rats.
RESUMO
Objective: To investigate the effect and mechanism of rapamycin inhibiting mammalian target of RAPA (mTOR) on heart valve cell calciifcation in experimental rats. Methods: The rat’s valvular interstitial cells were isolated and the cells were cultured in 4 groups:①Normal control group,②Calciifcation group,③Rapamycin group and ④Calciifcation + rapamycin group. The apoptosis rates of valvular interstitial cells were detected by flow cytometry, calcium deposition was observed by Alizarin S staining, the calcified nodules were counted and the protein expressions of bmp-2, osteocalcin, osteopontin, smad-1 and caspase-3 were examined by Western blot analysis. Results: The rat's valvular interstitial cells were suceessfully isolated; the cell apoptosis rates were similar among different groups,P>0.05. The calciifed nodule in Calciifcation group (0.471 ± 0.091) was more than Normal control group (0.104 ± 0.023), while the nodule in Calciifcation + rapamycin group (0.237 ± 0.039) was less than Calciifcation group, allP0.05. Conclusion: Rapamycin may down-regulate the targeting protein expressions of bmp-2, osteopontin and smad-1 via inhibiting mTOR, therefore, reducing the valvular interstitial cell calcification which might be related to mTOR pathway suppression in experimental rats.