Gymnema sylvestre

Gymnema sylvestre
in Karyavattam University Campus of Kerala, India.
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Gentianales
Family: Apocynaceae
Subfamily: Asclepiadoideae
Genus: Gymnema
Species: G. sylvestre
Binomial name
Gymnema sylvestre
R. Br.

Gymnema sylvestre (Sinhalese: මස්බැද්ද / Masbadda)(Malayalam:ചക്കരക്കൊല്ലി ,Tamil:சிறுகுறிஞ்சா) is an herb native to the tropical forests of southern and central India and Sri Lanka. Chewing the leaves suppresses the sensation of sweet. This effect is attributed to the eponymous gymnemic acids. G. sylvestre has been used in herbal medicine as a treatment for diabetes for nearly two millennia,[1] and though there is insufficient scientific evidence to draw definitive conclusions about its efficacy[2] two small clinical trials have shown gymnema to reduce glycosylated hemoglobin levels.[3] Common names include gymnema,[4] cowplant, Australian cowplant, gurmari, gurmarbooti, gurmar, periploca of the woods, meshasringa (मेषशृंग), Bedki cha pala (बेडकीचा पाला) and miracle fruit[5][6](also a common name for two unrelated plants).

Chemical composition

The major bioactive constituents of G. sylvestre are a group of oleanane-type triterpenoid saponins known as gymnemic acids. The latter contain several acylated (tigloyl, methylbutyroyl etc.,) derivatives of deacylgymnemic acid (DAGA) which is the 3-O-glucuronide of gymnemagenin (3,16,21,22,23,28-hexahydroxy-olean-12-ene). The individual gymnemic acids (saponins) include gymnemic acids I-VII, gymnemosides A-F, and gymnemasaponins.

G. sylvestre leaves contain triterpene saponins belonging to oleanane and dammarene classes. Oleanane saponins are gymnemic acids and gymnemasaponins, while dammarene saponins are gymnemasides. Besides this, other plant constituents are flavones, anthraquinones, hentriacontane, pentatriacontane, α and β-chlorophylls, phytin, resins, d-quercitol, tartaric acid, formic acid, butyric acid, lupeol, β-amyrin-related glycosides and stigmasterol. The plant extract also tests positive for alkaloids. Leaves of this species yield acidic glycosides and anthroquinones and their derivatives.

Use as herbal medicine

The effects of the herb are not entirely known. Gymnema reduces the taste of sugar when it is placed in the mouth. From extract of the leaves were isolated glycosides known as gymnemic acids, which exhibit anti-sweet activity.[7] This effect lasts up to about 2 hours. Some postulate that the herb may block sugar receptors on the tongue. This effect was observed in isolated rat neurons.[8]

The active ingredients are thought to be the family of compounds related to gymnemic acid: purified gymnemic acids are widely used as experimental reagents in taste physiology[9] and have also an anti-diabetic effect in animal models,[10] reduce intestinal transport of maltose in rats when combined with acarbose,[11] and reduce absorption of free oleic acid in rats.[12]

Historically, the leaves were used for stomach ailments, constipation, water retention, and liver disease; however, these claims are not supported by scientific studies.[13]

A water-soluble extract of G. sylvestre caused reversible increases in intracellular calcium and insulin secretion in mouse and human β-cells when used at a concentration (0.125 mg/ml) without compromising cell viability. This in vitro data suggests that extracts derived from G. sylvestre may be useful as therapeutic agents for the stimulation of insulin secretion in individuals with type 2 diabetes.[14] The rise in insulin levels may be due to regeneration of the cells in the pancreas.[15] G. sylvestre can also help prevent adrenal hormones from stimulating the liver to produce glucose in mice, thereby reducing blood sugar levels.[16] Clinical trials with type 2 diabetics in India have used 400 mg per day of water-soluble acidic fraction of the Gymnema leaves administered for 18–20 months as a supplement to the conventional oral drugs. During GS4 supplementation, the patients showed a significant reduction in blood glucose, glycosylated haemoglobin and glycosylated plasma proteins, and conventional drug dosage could be decreased. Five of the 22 diabetic patients were able to discontinue their conventional drug and maintain their blood glucose homeostasis with GS4 alone. These data suggest that the beta cells may be regenerated/repaired in Type 2 diabetic patients on GS4 supplementation. This is supported by the appearance of raised insulin levels in the serum of patients after GS4 supplementation.[17] Though for the moment G. sylvestre cannot be used in place of insulin to control blood sugar by people with either type 1 or type 2 diabetes, further evidence of its positive effect is accumulating[18]

Alternative names

Despite the part used being the leaf, one common name of this species is miracle fruit,[4][5][6] a name shared by two other species: Synsepalum dulcificum and Thaumatococcus daniellii.[5] Both species are used to alter the perceived sweetness of foods.

In English the species is also known as gymnema, cowplant, and Australian cowplant.

This species also goes under many other names such as; Gurmari, Gurmarbooti, Gurmar, periploca of the woods and Meshasringa. The Hindi word Gur-mar (Madhunaashini in Sanskrit, Chakkarakolli in Malayalam,Podapatri in Telugu), literally means sugar destroyer. Meshasringa (Sanskrit) translates as "ram's horn", a name given to the plant from the shape of its fruits. Gymnema derives from the Greek words "gymnos" (γυμνὀς) and "nēma" (νῆμα) meaning "naked" and "thread" respectively; the species epitheton sylvestre means "of the forest" in Latin.[19]

References

  1. "Gymnema sylvestre - Gurmar". Flowersofindia.net. Retrieved 2011-02-18.
  2. Yeh, GY; Eisenberg, DM; Kaptchuk, TJ; Phillips, RS (2003). "Systematic review of herbs and dietary supplements for glycemic control in diabetes". Diabetes Care 26 (4): 1277–94. doi:10.2337/diacare.26.4.1277. PMID 12663610.
  3. Nahas, Richard; Moher M (June 2009). "Complementary and alternative medicine for the treatment of type 2 diabetes". Can Fam Physicia 55 (6): 591–596. PMC 2694078. PMID 19509199.
  4. 4.0 4.1 Duke, James A., ed. (2002). Handbook of medicinal herbs (2nd ed.). CRC Press. p. 855. ISBN 0-8493-1284-1.
  5. 5.0 5.1 5.2 Wiersema, John Harry; León, Blanca (1999). World Economic Plants: A Standard Reference. CRC Press. p. 661. ISBN 0-8493-2119-0.
  6. 6.0 6.1 Rehm, Sigmund, ed. (1994). Multilingual dictionary of agronomic plants. Springer. p. 91. ISBN 0-7923-2970-8.
  7. Kinghorn, A. Douglas; Compadre, César M. (2001). "Less Common High-Potency Sweeteners". In Nabors, Lyn O'Brien. Alternative Sweeteners. CRC Press. pp. 209–33. ISBN 978-0-8247-0437-7.
  8. Lemon, CH; Imoto, T; Smith, DV (2003). "Differential gurmarin suppression of sweet taste responses in rat solitary nucleus neurons". Journal of neurophysiology 90 (2): 911–23. doi:10.1152/jn.00215.2003. PMID 12702710.
  9. Hellekant, G; Ninomiya, Y; Danilova, V (1998). "Taste in chimpanzees. III: Labeled-line coding in sweet taste". Physiology & behavior 65 (2): 191–200. doi:10.1016/S0031-9384(97)00532-5. PMID 9855466.
  10. Sugihara, Y; Nojima, H; Matsuda, H; Murakami, T; Yoshikawa, M; Kimura, I (2000). "Antihyperglycemic effects of gymnemic acid IV, a compound derived from Gymnema sylvestre leaves in streptozotocin-diabetic mice". Journal of Asian natural products research 2 (4): 321–7. doi:10.1080/10286020008041372. PMID 11249615.
  11. Luo, H; Wang, LF; Imoto, T; Hiji, Y (2001). "Inhibitory effect and mechanism of acarbose combined with gymnemic acid on maltose absorption in rat intestine". World journal of gastroenterology 7 (1): 9–15. PMID 11819725.
  12. Wang, LF; Luo, H; Miyoshi, M; Imoto, T; Hiji, Y; Sasaki, T (1998). "Inhibitory effect of gymnemic acid on intestinal absorption of oleic acid in rats". Canadian journal of physiology and pharmacology 76 (10–11): 1017–23. doi:10.1139/cjpp-76-10-11-1017. PMID 10100884.
  13. Shanmugasundaram KR; Panneerselvam C; Sumudram P; Shanmugasundaram ERB (1981). "Insulinotropic activity of G. sylvestre, R.Br. and Indian medicinal herb used in controlling diabetes mellitus". Pharmacol Res Commun 13 (5): 475–486. doi:10.1016/S0031-6989(81)80074-4. PMID 7027275.
  14. Asare-Anane, H; Huang, GC; Amiel, SA; Jones, PM; Persaud, SJ (2005). "Stimulation of insulin secretion by an aqueous extract of Gymnema sylvestre: role of intracellular calcium". Endocrine Abstracts 10: DP1.
  15. Persaud SJ; Al-Majed H; Raman A; Jones PM (1999). "Gymnema sylvestre stimulates insulin release in vitro by increased membrane permeability". J Endocrinol 163 (2): 207–212. doi:10.1677/joe.0.1630207. PMID 10556769.
  16. Gholap S; Kar A (2003). "Effects of Inula racemosa root and Gymnema sylvestre leaf extracts in the regulation of corticosteroid induced diabetes mellitus: involvement of thyroid hormones". Pharmazie 58 (6): 413–415. PMID 12857006.
  17. Baskaran, K.; Kizar Ahamath B, Radha Shanmugasundaram K, Shanmugasundaram ER. (Oct 1990). "Antidiabetic effect of a leaf extract from Gymnema sylvestre in non-insulin-dependent diabetes mellitus patients". J.Ethnopharmacol. 30 (3): 295–300. doi:10.1016/0378-8741(90)90108-6. PMID 2259217. Retrieved 8 August 2013.
  18. Joffe DJ; Freed SH (2001). "Effect of extended release gymnema sylvestre leaf extract (Beta Fast GXR) alone or in combination with oral hypoglycemics or insulin regimens for type 1 and type 2 diabetes". Diabetes in Control Newsletter 76 (1).
  19. "Gymnema". The New International Encyclopædia. Retrieved 2011-05-08.

Further reading

External links

Media related to Gymnema sylvestre at Wikimedia Commons