Rapamycin Attenuates Endothelial Apoptosis Induced by Low Shear Stress via mTOR and Sestrin1 Related Redox Regulation

Figure 5

Upregulation of sestrin1 expression by rapamycin protected ECs from LSS insults via mTORC2 inhibition. Upregulation of sestrin1 expression by rapamycin protected ECs from LSS insults via mTORC2 inhibition. (a) HUVECs were treated with siRNA against rictor, raptor, or scrambled control siRNA (ctrl siRNA). 48 h after transfection, cells were harvested for the detection of Rictor, Raptor, and GAPDH protein levels by western blot. ((b)-(c)) Percentage of knockdown rictor or raptor was analyzed relative to GAPDH, ^∗𝑃<0.05; 𝑛=3. ((d)-(e)) 48 h after transfection, sestrin1 expression was significantly elevated in rictor siRNA or raptor siRNA group, ^∗𝑃<0.05; 𝑛=4. (f) Rapamycin (RAPA) reduced LSS induced sestrin1 decreasing,^∗𝑃<0.05, 𝑛=4. (g) After mTORC1 inhibition with raptor siRNA transfection for 48 h, HUVECs were exposed to LSS or kept static. Expression of sestrin1 determined by real time PCR was reduced after LSS exposure, ^∗𝑃<0.05, 𝑛=4. (h) After inhibition of mTORC2 with rictor siRNA, sestrin1 expression was not decreased by LSS in HUVECs as compared with static group, 𝑃=0.7731, 𝑛=4.

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