Protective effect of losartan on injury induced by ox-LDL in endothelial cells and the relationship with asymmetric dimethylarginine / 中南大学学报(医学版)

ABSTRACT

OBJECTIVE@#To investigate the protective effect of losartan against on injury induced by ox-LDL in endothelial cells and the relationship with asymmetric dimethylarginine (ADMA).@*METHODS@#Endothelial injury was induced by incubation with ox-LDL 100 mg/L in cultured HUVECs for 24 h, and the levels of ADMA, lactate dehydrogenase (LDH), nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) in the conditioned medium were measured. The activity of dimethylarginine dimethylaminohydrolase (DDAH) of cultured endothelial cells was also determined.@*RESULTS@#Incubation of endothelial cells with ox-LDL 100 mg/L for 24 h induced a marked elevation of the levels of ADMA, LDH and TNF-alpha in the conditioned medium and a significant decrease in the activity of DDAH and the content of NO (P < 0.05). Pretreatment with losartan (10(-8) - 10(-6) mmol/L) significantly inhibited the increased levels of ADMA, LDH and TNF-alpha, attenuated the decreased levels of NO and the decreased activity of DDAH induced by ox-LDL (P < 0.05).@*CONCLUSION@#Losartan may preserve ox-LDL-induced endothelial cell injury by increasing the DDAH activity and decreasing the ADMA level.