4. Cellular mechanisms of potential anti-diarrhoea drugs isolated from Traditional Chinese Medicine (in collaboration with Prof. Brian J. Harvey, Royal College of Surgeon, Dublin, Ireland)

Berberine (黃連素) has been employed for over two thousand years as an Eastern remedy for gastroenteritis and secretory diarrhoea. Similarly, extracts of berberine-containing plants have served as traditional folk remedies in Hindu medicine. More recently, several small clinical trials have provided evidence that berberine is effective in treating secretory diarrhoea. Berberine, a benzodioxoloquinolozine alkaloid derived from plants of the genera Berberis and Coptis, has a varied pharmacology including antibiotic activity against bacteria, fungi, and protozoa and anti-motility properties. While these provide plausible proposals to partially explain its effects in-vivo, the mechanism(s) by which berberine improves diarrhoeal disorders remain to be elucidated. In this study we will determine the cellular signal pathways and membrane transporters involved in the anti-secretory and anti-motility effects of berberine. In particular, we will identify the K+ channel type targeted by berberine in human and rat isolated colon, and in the human colonic T84 cell line.

This work is made possible by an award from the Wellcome Trust (UK) Collaborative Research Grant.