Tacrolimus protects vascular endothelial cells from injuries caused by Ox-LDL by regulating endoplasmic reticulum stress

OBJECTIVE: To study the protective effect of tacrolimus on endothelial cells under the action of oxidized low-density lipoprotein (Ox-LDL), and to explore the mechanism of tacrolimus in protecting endothelial cells. MATERIALS AND METHODS: Human umbilical vein endothelial cells (HUVEC) were used and they were divided into the blank group, tacrolimus group, ox-LDL injury group, and tacrolimus + ox-LDL (tacrolimus treatment) group, for treatment. The cell viability was detected via methyl thiazolyl tetrazolium (MTT) assay; the cytotoxic response was detected via lactate dehydrogenase (LDH) release assay, and the proportion of apoptotic cells was detected via flow cytometry. Moreover, the releases of superoxide dismutase (SOD), reactive oxygen species (ROS), were detected, and the expression levels of apoptosis-related molecules, and the endoplasmic reticulum stress(ERS)-related molecules were detected via polymerase chain reaction (PCR) and Western blotting. RESULTS: Ox-LDL could significantly reduce the viability of endothelial cells, increase the cytotoxicity and induce the apoptosis, while tacrolimus could effectively reduce such a toxic effect in a dose-dependent manner (p<0.05). Also, tacrolimus could significantly reduce the oxidative stress response of cells caused by ox-LDL and the expressions of ERS-related proteins, and protect the cells from oxidative stress injury (p<0.05). CONCLUSIONS: Tacrolimus regulates ERS of endothelial cells to reduce ox-LDL-induced injuries.