Momordica cymbalaria fruit extract attenuates high-fat diet-induced obesity and diabetes in C57BL/6 mice.

OBJECTIVES: The present study was aimed to evaluate the effect of methanolic fruit extract of Momordica cymbalaria (MeMC) against high-fat diet-induced obesity and diabetes in C57BL/6 mice. MATERIALS AND METHODS: In the present study, six weeks old male C57BL/6 mice were divided into four groups. G-1 and G-2 served as lean control and HFD control, G-3 and G-4 received MeMC 25 and 50 mg/kg, BW doses; all the treatments were given for a period of 11 weeks. The parameters such as body weight, fasting blood glucose, insulin, cholesterol, free fatty acid, and oral glucose tolerance tests were performed, further, at the end of the study fasting body weight, and weights of organs such as the liver, heart, and adipose tissue were measured and the liver tissue was subjected to histopathology evaluation, and insulin resistance was expressed as HOMA-IR index. RESULTS: The high-fat diet fed C57 mice showed significant elevation of body weight (P<0.01), blood glucose (P<0.01), insulin (P<0.01), cholesterol (P<0.01), free fatty acid (P<0.01), and HOMA-IR index (P<0.01) along with significant elevation of all organ weights and reduction in oral glucose tolerance (P<0.01) and brown adipose weight (P<0.01). The histopathology showed significant fatty infiltration and hypertrophy of hepatocytes. Interestingly, MeMC (50 mg/kg) alleviated all the HFD-induced perturbances significantly. Further, the HPLC analysis of MeMC revealed the presence of gallic acid and rutin as chief ingredients. CONCLUSION: MeMC possesses potent antidiabetic activity and ameliorates insulin resistance in HFD diet fed C57 mice.

Methanolic leaf extract of Gymnema sylvestre augments glucose uptake and ameliorates insulin resistance by upregulating glucose transporter-4, peroxisome proliferator-activated receptor-gamma, adiponectin, and leptin levels in vitro.

AIMS: The present study was undertaken to evaluate the effect of methanolic leaf extract of Gymnema sylvestre (MLGS) on glucose transport (GLUT) and insulin resistance in vitro. MATERIALS AND METHODS: Peroxisome proliferator-activated receptor-gamma (PPAR-γ) and GLUT-4 expression were assessed in L6 myotubes for concluding the GLUT activity, and adiponectin and leptin expression was studied in 3T3 L1 murine adipocyte cell line to determine the effect of MLGS (250-750 µg/ml) on insulin resistance. RESULTS: The findings of the experiments have demonstrated a significant and dose-dependent increase in glucose uptake in all the tested concentrations of MLGS, further the glucose uptake activity of MLGS (750 µg/ml) was at par with rosiglitazone (50 µg/ml). Concomitantly, MLGS has shown enhanced GLUT-4 and PPAR-γ gene expressions in L6 myotubes. Furthermore, cycloheximide (CHX) had completely abolished the glucose uptake activity of MLGS when co-incubated, which further confirmed that glucose uptake activity of MLGS was linked to enhanced expression of GLUT-4 and PPAR-γ. In addition, in another experimental set, MLGS showed enhanced expression of adiponectin and leptin, thus confirms the ameliorative effect of MLGS on insulin resistance. CONCLUSION: These findings suggest that MLGS has an enhanced glucose uptake activity in L6 myotubes, and ameliorate the insulin resistance in 3T3 L1 murine adipocyte cell line in vitro.

Methanolic extract of Momordica cymbalaria enhances glucose uptake in L6 myotubes in vitro by up-regulating PPAR-γ and GLUT-4.

The present study was undertaken to evaluate the influence of the methanolic fruit extract of Momordica cymbalaria (MFMC) on PPARγ (Peroxisome Proliferator Activated Receptor gamma) and GLUT-4 (Glucose transporter-4) with respect to glucose transport. Various concentrations of MFMC ranging from 62.5 to 500 µg·mL(-1) were evaluated for glucose uptake activity in vitro using L6 myotubes, rosiglitazone was used as a reference standard. The MFMC showed significant and dose-dependent increase in glucose uptake at the tested concentrations, further, the glucose uptake activity of MFMC (500 µg·mL(-1)) was comparable with rosigilitazone. Furthermore, MFMC has shown up-regulation of GLUT-4 and PPARγ gene expressions in L6 myotubes. In addition, the MFMC when incubated along with cycloheximide (CHX), which is a protein synthesis inhibitor, has shown complete blockade of glucose uptake. This indicates that new protein synthesis is required for increased GLUT-4 translocation. In conclusion, these findings suggest that MFMC is enhancing the glucose uptake significantly and dose dependently through the enhanced expression of PPARγ and GLUT-4 in vitro.