Antioxidant effects of herbal therapies used by patients with inflammatory bowel disease: an in vitro study.
BACKGROUND
Herbal remedies used by patients for treatment of inflammatory bowel disease include slippery elm, fenugreek, devil's claw, Mexican yam, tormentil and wei tong ning, a traditional Chinese medicine. Reactive oxygen metabolites produced by inflamed colonic mucosa may be pathogenic. Aminosalicylates (5-ASA) are antioxidant and other such agents could be therapeutic.


OBJECTIVE
To assess the antioxidant effects of herbal remedies in cell-free oxidant-generating systems and inflamed human colorectal biopsies.


METHODS
Luminol-enhanced chemiluminescence in a xanthine/xanthine oxidase cell-free system was used to detect superoxide scavenging by herbs and 5-ASA, and fluorimetry to define peroxyl radical scavenging using a phycoerythrin degradation assay. Chemiluminescence was used to detect herbal effects on generation of oxygen radicals by mucosal biopsies from patients with active ulcerative colitis.


RESULTS
Like 5-ASA, all herbs, except fenugreek, scavenged superoxide dose-dependently. All materials tested scavenged peroxyl dose-dependently. Oxygen radical release from biopsies was reduced after incubation in all herbs except Mexican yam, and by 5-ASA.


CONCLUSIONS
All six herbal remedies have antioxidant effects. Fenugreek is not a superoxide scavenger, while Mexican yam did not inhibit radical generation by inflamed biopsies. Slippery elm, fenugreek, devil's claw, tormentil and wei tong ning merit formal evaluation as novel therapies in inflammatory bowel disease.
Langmead
L
L
Academic Department of Adult and Paediatric Gastroenterology, Barts and the London, Queen Mary's, School of Medicine and Dentistry, London, UK.
Dawson
C
C
Hawkins
C
C
Banna
N
N
Loo
S
S
Rampton
D S
DS
D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D000975:Antioxidants / Q000627:therapeutic use*; D002478:Cells, Cultured; D003113:Colonoscopy; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy* / Q000201:enzymology; D008297:Male; D019804:Mesalamine / Q000627:therapeutic use*; D008875:Middle Aged; D008517:Phytotherapy; D028321:Plant Preparations / Q000627:therapeutic use*; D014969:Xanthine Oxidase / Q000378:metabolism
D000894:Anti-Inflammatory Agents, Non-Steroidal; D000975:Antioxidants; D028321:Plant Preparations; D019804:Mesalamine; D014969:Xanthine Oxidase