Effects of Chinese herbal drug-containing serum on oxidative damage and apoptosis of umbilical vein endothelial cells induced by oxidized low-density lipoprotein

OBJECTIVE: To investigate the effects of Chinese herbal drug-containing serum, prepared by administration of Chinese herbal medicine for activating blood (Xiongshao Capsule, XS) or for activating blood and detoxifying (Xiongshao Capsule plus Huanglian Capsule, XSHL) in rats, on cell viability, oxidative damage and apoptosis of human umbilical vein endothelial cells (HUVECs) induced by oxidized low-density lipoprotein (ox-LDL). METHODS: Thirty-two rats were randomly divided into 4 groups: control group, positive control group (simvastatin 1.8 mg/kg), activating blood (XS, 0.135 g/kg) group, and activating blood and detoxifying (XS Capsule 0.135 g/kg and Huanglian Capsule 0.135 g/kg, XSHL) group. Corresponding drugs were continuously administered to the rats for 7 days and then drug-containing serum was harvested 1 hour after the last administration. HUVECs isolated from newborn children by collagenase digestion were stimulated by ox-LDL (100 μg/mL) [corrected] and incubated with corresponding drug-containing serum for 24 hours. Untreated HUVECs were also used as a normal control. The morphology and structure of HUVECs were observed by an inverted microscope. Cell viability was measured by methyl thiazolyl tetrazolium method, and cell membrane damage was determined by lactate dehydrogenase (LDH) leakage. Activity of superoxide dismutase (SOD) was examined by spectrophotometry, and content of malondialdehyde (MDA) in the cell lysate was examined by thiobarbituric acid assay. HUVECs were stained with Annexin V-fluorescein isothiocyanate and propidium iodide and analyzed on a flow cytometry to determine apoptosis. RESULTS: Compared with the normal HUVECs, the cell viability and the activity of SOD were significantly decreased while the content of MDA and apoptosis rate were significantly increased after 24-hour ox-LDL stimulation (P<0.01, P<0.05). Simvastatin-, XS-, and XSHL-containing serum significantly promoted the ox-LDL-stimulated HUVEC viability and inhibited early apoptosis (P<0.01, P<0.05), while had no significant effect on LDH leakage. Simvastatin-containing serum and XS-containing serum also showed significant decrease in MDA content and increase in SOD activity, while XSHL-containing serum showed no significant effects. There was no significant difference between the XS-containing serum group and the XSHL-containing serum group. CONCLUSION: Both sera containing XSHL and XS show protective action against the oxidative damage and apoptosis of HUVECs induced by ox-LDL.