Aegle marmelos impedes onset of insulin resistance syndrome in rats provided with drinking fructose from weaning to adulthood stages of development - a mechanistic study.

In this study, we explored the effect of aqueous extract of leaves of Aegle marmelos (AM) on hepatic carbohydrate metabolism and insulin downstream signalling in rats given fructose (15%) in drinking water from weaning to adulthood. Wistar albino rats (4 weeks old) were randomly divided into normal control (NC), fructose control (FC), and treatment (AMT) groups and were fed for a period of 8 weeks the following diets: chow + water, chow + fructose (15%), and chow + fructose (15%) + AM (500 mg/kg per day, p.o.), respectively. Compared with the NC group, the FC group was found to have significantly (p < 0.05) raised levels of fasting blood glucose, lipid, visceral mass, plasma insulin and leptin, glycogen, and gluconeogenesis enzyme but decreased glycolytic enzyme activity. Raised levels of glucose transporter 2 protein but decreased activity of phosphatidylinositol-3-kinase (PI3K/Akt) and Janus kinase - signal transducer and activator of transcription-3 (JAK-STAT3) in hepatic tissue indicate a state of insulin and leptin resistance in the FC group. A significant (p < 0.05) lowering of physical and glycemic parameters, strengthening of the hepatic glycolytic pathway over the gluconeogenic pathway, and upregulation of the PI3K/Akt and JAK-STAT3 pathways was observed in the AMT group, as compared with the FC group. For the first time, the mechanism underlying the development of insulin resistance syndrome is delineated here, along with the potential of A. marmelos to impede it.

Interaction of aqueous leaf extract of Aegle marmelos (L.) Corr. with cholinergic, serotonergic and adrenergic receptors: an ex vivo study.

OBJECTIVES: The aim was to study interaction of aqueous leaf extract of Aegle marmelos (AM) with cholinergic, serotonergic, and adrenergic receptor systems using appropriate rat tissues-ileum, fundus and tracheal chain, respectively. MATERIALS AND METHODS: Cumulative concentration-response curves (CRC) were constructed at various doses on each tissue for AM and respective standard agonist. The CRC was again plotted in presence and absence of respective standard antagonist to confirm the interaction of receptor system and AM. RESULTS: AM induced concentration-dependent contractions in isolated rat ileum (0.2-6.4 mg/ml) and fundus (0.2-3.2 mg/ml) that were inhibited significantly (P < 0.05) in the presence of atropine (10(-7) M) and ketanserin (10(-6) M), respectively. The relaxant effect, produced by AM (0.2 mg/ml) on carbachol (10(-5) M) precontracted rat tracheal chain, was also inhibited significantly (P < 0.05) by propranolol (1 ng/ml). CONCLUSION: It may be concluded that AM possesses agonistic activity on cholinergic, serotonergic and adrenergic receptors.