Plant Compounds Used to Treat the Digestive System

1. Plant Compounds Used to Treat the Digestive System

2. Irritable Bowel Syndrome (IBS) • Mentha X piperita – peppermint • Traditional ethnomedical uses: • digestive problems • intestinal spasms • irritable bowel syndrome

3. Irritable Bowel Syndrome (IBS) • The active compound in peppermint is peppermint oil: contains high concentration of menthol, also some menthone • Numerous double-blind placebo controlled human clinical trials have demonstrated the effectiveness of peppermint oil in treating IBS • Cappello, G.; et al. (2007). Peppermint oil (Mintoil) in the treatment of irritable bowel syndrome: A prospective double blind placebo-controlled randomized trial. Digestive and Liver Disease39 (6): 530–536. • 75% of patients who took peppermint oil capsules for four weeks had a significant reduction in IBS

4. after dinner mints • Peppermint oil also relaxes the gastro-esophageal sphincter, which promotes burping

5. Constipation • Plantago afra, P. ovata – psillium • Traditional ethnomedical uses: seeds and seed husks used as a laxative to treat constipation • Active components: whole seed preparation • Mechanism: seeds add bulk to soften stools (takes 1-3 days)

6. Constipation • Senna alexandria – senna • seeds traditionally used to treat constipation • sennosides A & B are the active compounds

7. Constipation • Pharmaceutical derivative of sennosides is danthron • a stimulant laxative that causes muscle contractions of the intestinal wall • now considered carcinogenic, so only used in terminally ill patients (e.g., for opiate-related constipation)

8. Constipation • Rhamnus spp. – cascara sagrada, buckthorn, bear berry • Active components – anthraquinone derivatives • R. purshiana (cascara sagrada) was used by indigenous people of CA and the Pacific NW, also early settlers • Stimulant laxative • Common ingredient in over-the-counter laxatives until it was banned by the FDA in May, 2002.

9. Constipation • Ricinus communis – castor oil • seed oil is used in low dosage as a laxative, in high dosage as a cathartic • in low dose, caster oil acts directly on the intestinal mucosa to change water/electrolyte balance (osmotic laxative)

10. Diarrhea • Papaver somniferum – opium poppy • In its native range, Hmong and many other cultural groups used opium fruit capsule latex to treat diarrhea

11. Diarrhea • Traditional active opium preparations for treatment of diarrhea: • morphine (single compound) • opium tincture • paregoric of opium (opium, camphor oil, anise oil, & benzoic acid) • Synthetic opiate treatments: • loperamide (Imodium) • diphenoxylate in Lomotil (also contains atropine)

12. Diarrhea • Opiates reduce diarrhea by: • reducing propulsive contractions in the large and small intestine • reducing gastric secretions • this occurs through agonism of opioid recepters in the gut

13. Diarrhea • Atropa belladona – belladona • Anticholinergic effects of atropine at muscarinic receptors in intestine tissues reduce intestinal motility (mimic sympathetic response) • Hyoscyamus niger or Madragora officinarum in the Solanaceae can also be taken as intestinal antispasmodics (hyoscyamine = active compound)

14. Diarrhea • Croton lechleri – sangre de drago • Native to western Amazon basin, S. America • Traditional ethnomedical uses: • diarrhea • ulcers • herpes skin infections • wound healing • tuberculosis • pneumonia

15. Diarrhea • Sangre de drago’s anti-diarrhea action is due to a proanthocyanidin compound • acts through inhibition of cAMP-mediated fluid and chloride secretion in the villi of the small intestine • useful in treating secretory diarrheas (e.g., travelers’ diarrhea, HIV-associated diarrhea)

16. Diarrhea • Berberis spp. – barberry (Europe), Oregon grape (W. US) • Active compound: berberine • Mechanism: berberine directly inhibits ion transport across the intestinal endothelium • Useful for secretory diarrheas & dysentery

17. Nausea / Motion Sickness • Zingiber officinale – ginger • clinical trials (and long use in Chinese traditional medicine & Ayurveda) indicate ginger is an effective antiemetic • S. Phillips, R. Ruggier, & S. E. Hutchinson. 1993. Zingiber officinale (Ginger)–an antiemetic for day case surgery. Anesthesia 48(8): 715-717.

19. Anti-helminthic Plants • Anti-helminthics are drugs that expel intestinal worms from the body, either by stunning (aka vermifuges) or killing (aka vermicides) the worms • It is estimated that ¼ of the world’s population is infected with intestinal helminths • Children are particularly susceptible to helminthic infection, which is associated with poor immune response, malnutrition, anemia, and stunted/slowed physical and intellectual development

20. Anti-helminthic Plants • Many plants contain compounds that are toxic to insects (herbivores) - some of these compounds are effective in combating intestinal worms

21. Anti-helminthic plant compounds • Nicotiana tabacum, N. rustica - tobacco • Nicotine is an effective insect neurotoxin, and tobacco was traditionally used as an anti-helminthic • N. tabacum is the variety of tobacco commonly grown for smoking – N. rustica has a much higher (3x) nicotine content in its leaves, and is now grown as a source of nicotine for organic pesticides

22. Anti-helminthic plant compounds • Dryopteris filix-mas – Male Fern, Worm Fern • Very common fern throughout N. temperate areas of the world • Until recent times, the rhizome was used to expel tapeworms • The only fern to have appeared in the USP

23. Anti-helminthic plant compounds • Artemisia maritima, A. cina, A. absinthum, Artemisia spp. – wormwood, wormseed • Traditionally used as antihelminthics (for roundworms) • Active compound: santonin • No longer used, as it had potentially fatal side effects (convulsions, seizures…) • Also altered color vision (xanthopsia)

24. Anti-helminthic plant compounds • Tanacetum vulgare – Tansy • Related to wormwood (also in the Asteraceae) • Contains compounds toxic to insects, including thujone (like wormwood) and possibly santonin • Long used as an insect repellent, preservative, and worm treatment

25. Anti-helminthic plant compounds • Punica granatum – pomegranate • peel of fruit high in tannins, traditionally used as a treatment for intestinal worms in Ayurvedic and Chinese medicine

26. Anti-helminthic plant compounds • Agrimonia pilosa – agrimony • native to China • traditionally used for a variety of purposes, including anti-infective and haemostatic • source of compound agrimophol, which is an antihelminthic

27. Anti-helminthic plant compounds • Areca catechu – areca palm (areca nut) • source of alkaloid compound arecoline • arecoline is a nicotinic and muscarinic receptor agonist • also acts as an antihelminthic, and is used to treat worms

28. Anti-helminthic plant compounds • Peganum harmala – Harmal • Native from Eastern Mediterranean to India • Active compound in harmal seeds is harmaline – a CNS stimulant and reversible MAO-A inhibitor • Seeds traditionally ground and used as an anti-helminthic • Ancient Greks used harmala seeds to get rid of tapeworms

29. Anti-helminthic plant compounds • Digenea simplex • a marine red algae native to Eastern Pacific (Philippines, Japan) • used as an antihelminthic (round worms) in Eastern medicine • source of kainic acid (active compound)

30. Anti-helminthic plant compounds • Kainic acid is an agonist of glutamate (stimulatory) receptors in the brain • In higher concentrations, it is a potent CNS stimulant and neurodegenerative agent – used in neuroscience research to model epilepsy and Alzheimer’s

31. Anti-helminthic plant compounds • Quisqualis indica – Rangoon creeper • Native to SE Asia • Fruit/seeds used to kill intestinal worms

32. Anti-helminthic plant compounds • Source of quisqualic acid, an agonist of AMPA (glutamate) receptors in the brain • Like kainic acid, quisqualic acid is also used in neurological research due to its excitotoxicity in the neurons of the brain and spinal cord