The herbal combination preparation STW 5 is active in DSS-induced colitis

Herbal extracts often have strong anti-inflammatory properties. To these belongs the phytomedicine STW 5, a combination preparation of nine herbal extracts used in the therapy of functional gastrointestinal diseases, including irritable bowel syndrome (IBS). Earlier pharmacological studies, e.g. in TNBS induced colitis, an experimental model for Crohn's disease, suggest that STW 5 has anti-inflammatory properties. So we decided to test it also in a model of Dextran Sodium Sulphate (DSS) induced colitis, which relates more to ulcerative colitis in man. DSS was administered to rats in the drinking water for 7 days, leading to lesions in the colon, associated with changes in plasma levels of various relevant mediators. STW 5 was administered once daily orally in 3 dose levels (1, 2.5 and 5ml/Kg) during DSS administration. It reduced the symptom score, colon shortening and colon mass index in a dose dependent manner. The levels of TNFα and myeloperoxidase activity (as inflammation parameters) as well as the levels of glutathione, glutathione peroxidase, and superoxide dismutase (as oxidative stress parameters) were measured in colonic tissue as well as in the blood. The changes in these parameters induced by DSS were favourably influenced by STW 5 in a manner comparable to sulfasalazine (300mg/Kg) which was used as a reference standard drug. The findings point to the potential therapeutic usefulness of STW 5 not only in IBS, but also in ulcerative colitis.