Cystatin C protection of human umbilical vein endothelial cell against oxidative stress injury through activating autophagy

Cystatin C (CysC)-induced autophagy may play a beneficial role in preventing subarachnoid hemorrhage-induced cerebral vasospasm. The role of CysC in endothelial cells (ECs) autophagy is unknown. This study explores the role of CysC during the process of oxidative stress in human umbilical vein endothelial cells (HUVECs). Oxidized LDL (oxLDL) was used to stimulate HUVECs in vitro study. The lactate dehydrogenase (LDH) release and malondialdehyde (MDA) level were assayed. Western blot is used to detect the expression levels of LC3 and P62. The present study demonstrated that LDH release and MDA levels increased after oxLDL exposure, however, CysC and NAC (N-acetyl-cysteine) decreased LDH release and MDA levels induced by oxLDL. The difference was a statistically significant amount (P<0.05). Additionally, compared with oxLDL group, CysC increased LC3II expression and alleviated P62 expression in CysC+oxLDL group (P<0.05). The results of the present study suggested that CysC protects against oxidative stress injury through activating autophagy in HUVECs. Key words: oxLDL, oxidative stress, CysC, human umbilical vein endothelial cells (HUVECs), autophagy.