Comparative effects of STW 5 and STW 5-II in dextran sodium sulfate-induced colitis

Abstract

STW 5 (Iberogast®) is an herbal preparation consisting of nine different extracts namely, Iberis amara, Matricaria recutita, Carum carvi, Melissa officinalis, Mentha piperita, Glycyrrhiza glabra, Silybum marianum, Angelica archangelica and Chelidonium majus. A sister preparation, STW 5-II, has been developed lacking the 3 last components. Both STW 5 and STW 5-II were found effective clinically in gastrointestinal disorders such as functional dyspepsia and irritable bowel syndrome (1,2,3). We have recently shown that STW 5 is useful in experimentally induced ulcerative colitis (4). Present study compares the effect of both preparations in colitis induced in Wistar rats by giving them 5% Dextran sodium sulfate (DSS) in drinking water for 1 week. Treated rats were given either STW 5 or STW 5-II (2 ml/Kg) orally during DSS administration and for 1 week after its stoppage. One day later, animals were sacrificed, the colon was excised to determine its length and weight. Colon segments were examined histologically, while homogenates were used to assess relevant biochemical parameters and cytokines. Both preparations had similar qualitative effects on colon length and mass index, protected against inhibition of reduced glutathione, glutathione peroxidase and superoxide dismutase induced by DSS, against the elevation in myeloperoxidase, and protected against the elevation in TNFα and CINC-3 (inflammatory mediators). The histological changes induced by DSS were to a large extent prevented by both. The findings point to the potential usefulness of both STW 5 and STW 5-II in ulcerative colitis with only few differences in their efficacy.