Effect of Caspase Inhibitor Ac-DEVD-CHO on Apoptosis of Vascular Smooth Muscle Cells Induced by Artesunate

Abstract

Numerous studies have shown that the proliferation and apoptosis of vascular smooth muscle cells play a key role in restenosis. Artesunate is a triterpenoid with a peroxide structure and its antimalarial, antitumor, and antiangiogenetic activities can inhibit the proliferation and apoptosis of multifarious cells. Apoptosis is caused by the activation of a series of intracellular proteolytic enzymes, among which caspase-dependent apoptosis was the earliest to be recognized. The purpose of this article is to study the effects of caspase-3 inhibitor Ac-DEVD-CHO on proliferation and apoptosis of vascular smooth muscle cells induced by Artesunate and to explore the mechanism of Artesunate-induced apoptosis of vascular smooth muscle cells. By using the method based on methyl thiazolyl tetrazolium to observe the effects of Artesunate on the growth and proliferation of vascular smooth muscle cells; observing the change in cell shape before and after Artesunate administration by transmission electron microscopy; detecting the changes in cell cycle and apoptosis rates before and after drug administration by flow cytometry; detecting the activity of caspase-3 in the caspase apoptosis pathway by the Western Blot method, we found that Artesunate inhibits the growth and proliferation of vascular smooth muscle cells in a dose- and time-dependent manner within the concentration range of 7.5–120 μg/mL, and the inhibition rate of Artesunate can be as high as 89.49 % at a concentration of 120 μg/mL after acting for 72 hours; vascular smooth muscle cells show a typical apoptosis peak due to the effects of higher concentration of Artesunate. Compared with the control group, the higher-concentration group shows major variability, Ac-DEVD-CHO, however, can significantly decrease this induction; it has been detected by Western Blot that Artesunate can induce caspase-3 activity dramatically in vascular smooth muscle cells, but this activation may be remarkably inhibited by Ac-DEVD-CHO.