Antidiabetic effect of Dodonaea viscosa (L). Lacq. aerial parts in high fructose-fed insulin resistant rats: A mechanism based study.

To study the effect and mode of action of water extract (DVW) and polar fraction of ethanol extract (DVE-4) of D. viscosa in high-fructose diet induced insulin resistance in male Wistar rats. D. viscosa’s effects were evaluated on a battery of targets involved in glucose homeostasis (in vitro studies). Rats were rendered insulin resistant by feeding 66% (w/w) fructose and 1.1% (v/w) coconut oil mixed with normal pellet diet (NPD) for six weeks. DVW and DVE4 at different doses were administered simultaneously. At the end of the study, blood glucose, oral glucose tolerance test, lipid profile and insulin were estimated and homeostatic model assessment (HOMA) levels were calculated. In addition, enzymatic and non-enzymatic liver antioxidant levels were also estimated. Quantification of biomarker quercetin was done using HPLC. Fructose diet with DVW, DVE-4 significantly reduced blood glucose, serum insulin, HOMA, lipid profiles and significantly improved glucose tolerance and HDL-c levels. In addition, these extract and fraction also decreased oxidative stress by improving endogenous antioxidants. In different bioassays, DVW and DVE-4 inhibited protein tyrosine phosphatase-1B with IC50 65.8 and 54.9 g/ml respectively and showed partial inhibition of dipeptidyl peptidase-IV. Moreover, DVW and DVE-4, at 10 mg/ml showed 60 and 54.2% binding to peroxisome proliferator-activated receptor-g. Further, 2.1% (w/w) of quercetin was quantified in bioactive-DVE-4 using HPLC method. The results provide pharmacological evidence of D. viscosa in treatment of prediabetic conditions and these effects may be mediated by interacting with multiple targets operating in diabetes mellitus.

Evaluation of Ammannia baccifera Linn. for antiurolithic activity in albino rats.

Ethanolic extract of A. baccifera was tested for its antiurolithic activity in male albino rats. Urinary stones were induced by implantation of zinc discs in the urinary bladder. The stones formed were mainly of magnesium ammonium phosphate with traces of calcium oxalate. Ethanolic extract of A. baccifera (2g/kg/day, po) was found to be effective in reducing the formation of stones as also in dissolving the pre-formed ones. There was a significant increase in the urinary excretion of calcium, magnesium and oxalate, four weeks after implantation of zinc discs. Treatment with A. baccifera has significantly reduced calcium and magnesium levels in the prophylactic group while it has reversed the levels of these ions to normal values in the curative group.

Evaluation of Musa (Paradisiaca Linn. cultivar)--"Puttubale" stem juice for antilithiatic activity in albino rats.

The fresh juice of Musa stem (Puttubale) was tested for its antilithiatic activity. Zinc discs were implanted in the urinary bladder of albino rats to induce urolithiasis. The stones formed were mainly of magnesium ammonium phosphate with traces of calcium oxalate. Musa stem juice (3 mL/rat/day orally) was found to be effective in reducing the formation and also in dissolving the pre-formed stones.