Effects Of Propofol On The Expression And Activity Of Angiotensin-converting Enzyme In Human Pulmonary Microvascular Endothelial Cells Induced By Lipopolysaccharide In Vitro

Objective This study is aimed to investigate the effects of propofol pretreatment on the expression and activity of angiotensin-converting enzyme (ACE) in human pulmonary microvascular endothelial cells (HPMVCs) induced by lipopolysaccharide (LPS).Methods HPMVCs were randomly assigned to one of the following four groups (n=8each):control group, propofol (50μM), LPS (5μg/ml) and propofol (50μM) combined with LPS. Propofol was administered1h before LPS. After being incubated for12h,24h,48h and72h, cell viability was determined by Cell Counting Kit-8(CCK-8) assay. After incubation for12h, ACE activity in culture medium as well as in cell lysate were determined by an improved spectrophotometric method, real-time PCR was applied for detecting the mRNA expression of ACE, TNF-a, IL-1β and MCP-1, and the protein concentration of TNF-a, IL-1β and MCP-1in medium was detected with ELISA kits.Results Survival of HPMVCs at12h,24h,48h and72h was not influenced by drugs in each group (P>0.05). Propofol alone had no significant effect on HPMVCs in terms of ACE activity and expression, as well as the expression of TNF-a, IL-1β and MCP-1(P>0.05). LPS significantly increased ACE activity in the medium but decreased both cellular ACE activity and ACE mRNA expression. LPS increased expression of TNF-a, IL-1β and MCP-1(P<0.05). Pretreatment of propofol significantly attenuated LPS-induced effects on HPMVCs (P<0.05).Conclusions Propofol may protect pulmonary microvascular endothelial cells via up-regulation of ACE expression and inhibition of TNF-α, IL-1β and MCP-1level.