Interleukin-1β and tumor necrosis factor-α affect cytochrome P450 expression in cynomolgus macaque hepatocytes

The cynomolgus macaque, partly due to its evolutionary closeness to humans, is an important nonhuman primate species used in drug metabolism studies. In humans, expressions of cytochromes P450 (P450s), including the important drug-metabolizing enzyme P450 3A4, are affected by various cytokines. However, this phenomenon has not been fully investigated in cynomolgus macaques. In this study, the effects of cytokines on P450 expression were investigated using the quantitative polymerase chain reaction to evaluate mRNA expression. Hepatocytes from cynomolgus macaques were treated with lipopolysaccharide and various cytokines, including interleukin (IL)-1β, IL-2, IL-6, interferon-γ, and tumor necrosis factor-α, and the expression levels of 11 P450s were compared with those of solvent-treated controls. Tumor necrosis factor-α significantly decreased cynomolgus P450 2C8 and 2C76 mRNA expression in multiple lots of cynomolgus hepatocytes investigated. IL-1β significantly decreased cynomolgus P450 1A1, 2C8, 2C19, and 2C76 mRNA expression, but increased P450 3A5 mRNA expression in multiple lots of hepatocytes. Moreover, P450 1A1-and 2C19-mediated drug oxidations were significantly and dose-dependently suppressed by IL-1β, under the present limited conditions. These results suggest that cytokines can influence hepatic P450 mRNA expression levels in cynomolgus macaques, just as cytokines are reported to affect P450 expression in humans.