Inhibition of histamine-induced inflammatory reactions in intestinal mucosa by STW 5

Herbal medicine is a therapeutic option in the therapy of irritable bowel syndrome (IBS), a disease, for which an inflammatory etiology is discussed. In such inflammatory reactions in the gastrointestinal tract, histamine seems to be an important trigger. So the question raised, whether STW 5, a herbal medicine with clinically proven efficacy in the therapy of IBS (2), and consisting of a fixed combination of 9 herbal extracts, has anti-inflammatory and antioxidant effects (3). For the measurements of these effects a pharmacological model involving mucosa preparations from mouse ileum was developed. As a marker of inflammatory reactions, free radical production was measured via luminol-enhanced chemiluminescence. Histamine (5 to 100µmol/L) strongly increased this parameter. Similar to the antioxidant trolox, STW 5 had a significant inhibitory effect even in dilutions down to 0.1µl/ml). From the extracts contained in STW 5, those from peppermint and chamomile showed highest effects, that of greater celandine herb was least active. It can be concluded, that ileal mucosa preparations stimulated by histamine are a model with significant relevance in studies on diseases involving intestinal inflammation. The inhibitory effects exerted by STW 5 and its constituents in that reaction might be involved in its therapeutic effects.

References: 1. Breunig et al. 2007, J Physiol 583:731.

2. Madisch et al. 2004, Aliment Pharmacol Ther 19, 271–279; Germann et al. 2006, Phytomedicine, 13, SV, 45–50.