Disease relevance of Gymnema

• OBJECTIVES: In light of evidence that some complications of diabetes mellitus may be caused or exacerbated by oxidative damage, we investigated the effect of Gymnema montanum leaf extract (GLEt) on tissue antioxidant defense systems in alloxan-induced diabetes in rats [1].
• The complete amino acid sequence of a sweet-taste-suppressing peptide, gurmarin, from the leaves of Gymnema sylvestre was determined by the Edman analysis of peptides derived from digests obtained with Staphylococcus aureus V8 protease, pyroglutamyl aminopeptidase, and lysyl endopeptidase [2].
• GS4, a water-soluble extract of the leaves of Gymnema sylvestre, was administered (400 mg/day) to 27 patients with insulin-dependent diabetes mellitus (IDDM) on insulin therapy [3].

High impact information on Gymnema

• Gymnemic acids are the saponins with a triterpenoid structure contained in Gymnema sylvestre leaves and have the hypoglycemic effects [4].
• Fecal steroid excretion is increased in rats by oral administration of gymnemic acids contained in Gymnema sylvestre leaves [4].
• An extract of Gymnema sylvestre leaves and purified gymnemic acid inhibits glucose-stimulated gastric inhibitory peptide secretion in rats [5].
• The increase in the portal immunoreactive gastric inhibitory peptide induced by glucose was significantly depressed by concomitantly infused leaf extract of Gymnema sylvestre, purified gymnemic acid and phlorizin but not by cytochalasin B [5].
• Gurmarin (10 microg/ml), a protein extracted from Gymnema sylvestre, depressed significantly (40-50%) the phasic taste responses to sugars (sucrose, fructose, lactose, and maltose) and saccharin sodium recorded from the greater superficial petrosal nerve (GSP) innervating palatal taste buds in the rat [6].

Biological context of Gymnema

• Effects of seishin-renshi-in and Gymnema sylvestre on insulin resistance in streptozotocin-induced diabetic rats [7].
• Comparative effects of chromium, vanadium and gymnema sylvestre on sugar-induced blood pressure elevations in SHR [8].
• Structure-activity relationships of triterpenoid derivatives extracted from Gymnema inodorum leaves on glucose absorption [9].
• The evoked potentials for four taste qualities (i.e., sweet-sucrose, salty-sodium chloride, sour-tartaric acid, and bitter-quinine-HCl) were measured before and after treatment with a sweet suppressing agent (i.e., gymnema sylvestre extract) to the tongue of a human [10].

Anatomical context of Gymnema

• Gastric inhibitory peptide release into the portal vein in response to duodenal infusion of D-glucose was studied in the presence of a leaf extract of Gymnema sylvestre, purified gymnemic acid and inhibitors of some putative glucose sensors and carriers in the intestinal lumen [5].
• Furthermore, pectic substances, including those purified from Gymnema sylvestre, inhibited histamine release from isolated rat peritoneal mast cells, which had been induced by the antigen [11].

Associations of Gymnema with chemical compounds

• Preference for 0.01 M sucrose and a mixture of 0.03 M sucrose and 0.03 mM quinine-HCl significantly decreased at 1-2 days after the start of the gymnema diet and subsequently returned closely to the control levels within about a week [12].
• Pregnane glycosides, gymnepregosides G-Q from the roots of Gymnema alternifolium [13].
• Three new oleanane-type triterpene glycosides (1-3), along with the sodium salt of alternoside II (4), were isolated from an ethanol extract of the leaves of Gymnema sylvestre [14].
• A new sweet taste inhibitor (Gymnema sylvestre extract) strongly suppressed neural responses to mixtures of MSG and IMP as well as sucrose, but only weakly or negligibly to individual solutions of these umami substances [15].
• The administration of the dried leaf powder of Gymnema sylvestre regulates the blood sugar levels in alloxan diabetic rabbits [16].

References