The Antioxidant Effects of Propofol in Menadione-Induced Oxidative Stress in Human Monocyte THP-1 Cells

Abstract

Background: Propofol, thiopental, citosol, and midazolam are widely used as sedatives for the critically ill in the intensive care unit. These patients usually suffer from cellular injuries caused by oxidative stress from free radicals, predominantly due to the lack of a sufficient defense system against these species. Therefore, the antioxidant activities of sedative drugs may be clinically important. We attempt to evaluate the antioxidant and reactive oxygen species scavenging activities of these clinically relevant intravenous sedatives. Methods: By using Menadione, Hydrogen peroxide and Cumene hydroperoxide to create oxidative stress in human monocyte THP-1 cell line, we evaluate the antioxidative activity of propofol, thiopental, citosol, and midazolam by means of flow cytometry to investigate the intracellular reactive oxygen species scavenging ability of these drugs in human monocyte THP-1 cell line. Results: Propofol expressed an excellent scavenging activity compared with the other intravenous anesthetics, especially on menadione-induced superoxide in THP-1 cells. Propofol also significantly inhibits the intracellular GSH depletion and the decrease of mitochondrial transmembrane potential (△Ψ(subscript m)) induced by menadione in THP-1 cells. The expression of two antioxidant enzymes, superoxide dismutase (SOD) and gamma-glutamylcysteine synthetase (y-GCS), is inhibited by menadione treatment. Pretreatment with propofol can maintain the expression of SOD and y-GCS in menadione-treated THP-1 cells. The expression of another antioxidant enzyme, catalase, is not obviously affected by menadione and propofol. Conclusions: Propofol, of the four drugs tested in the present study, showed the most antioxidant and reactive oxygen species scavenging activities.