3. Effect of Scutellariae radix and its major flavonoids on experimental ulcerative colitis in rats

Scutellariae Radix (Huangqin), the root of Scutellaria baicalensis Georgi, has been frequently used in combination with other herbs in Kampo medicines or Traditional Chinese medicines (TCM) for centuries. Scutellariae Radix has been shown to possess anti-inflammatory, anti-pyretic, anti-allergic, anti-convulsant, anti-viral and anti-tumor properties. Therefore, it has been used to treat inflammatory - related disorders such as gastroenteritis in China and Japan for many years. Many biological activities of Scutellariae Radix are related to the flavonoids in the herb. Examples are baicalein, baicalin, and wogonin.

Inflammatory bowel disease (IBD) includes both ulcerative colitis and Crohn's disease, which are major chronic inflammatory diseases of the gastrointestinal tract in human. Conventional therapies used in IBD are not totally successful and their side effects remain a major clinical problem. Therefore, there is an increasing interest in using TCM as an alternative or adjunct therapy. The most frequently used TCM is Oren-gedoku-to (Huang Lian Jie Du Tang). It is a Traditional Chinese herbal medicine consisting of a mixture of four herbs, including Scutellariae Radix. Among the four herbs, recent studies suggest that Scutellariae Radix has the strongest pharmacological effect against murine colitis and baicalein is the most active ingredient. However, the physiological basis and the precise mechanism of action of Scutellariae Radix or its individual constituents are still unclear.

The purpose of the present proposal is to investigate whether the total extract and the major flavonoids derived from Scutellariae Radix have beneficial effect in treating experimental ulcerative colitis in rats. Experiments will be conducted using morphological, histological, biochemical and electrophysiological approaches.

This work is made possible by an award from the Direct Grant of Research, CUHK.