Effects of the prostaglandin analogue misoprostol on inflammatory mediator release by human monocytes

The effect of misoprostol (M) on IL-1 beta, TNF-alpha, and lipid mediator release (assessed by RIA) by adherent (assessed by electron microscopy) human monocytes were studied in vitro. Human monocytes stimulated with E. Coli-derived lipopolysaccharide showed an increase in both IL-1 beta and TNF-alpha release. Incubation of the monocytes with LPS and M (18 hrs.), resulted in a reduction of both IL-1 beta and TNF-alpha levels. Leukotriene B4 levels did not increase in response to LPS or M. LPS also caused an increase in thromboxane (TXB2). M decreased TXB2 levels. 6-keto PGF1 alpha (6KP). Incubation with LPS and M stimulated release. LPS caused an increase in PGE2 levels. M (100 microM) caused an increase in PGE2 levels, M (1 microM) had no effect on PGE2. These data suggest a possible immunomodulatory role for misoprostol in inflammatory diseases.