Effect and Mechanism of Rapamycin Inhibiting mTOR on Heart Valve Cell Calcification in Experimental Rats / 中国循环杂志

ABSTRACT

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 groups①Normal 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.