(+)-Catechin & Proanthocyanidin Fraction of Uncaria gambir Roxb. Improve Adipocytes Differentiation & Glucose Uptake of 3T3-L1 Cells Via Sirtuin-1, Peroxisome Proliferator-Activated Receptor γ (PPAR γ), Glucose Transporter Type 4 (GLUT-4) Expressions

Purpose: To improve adipocytes differentiation & glucose uptake activity of 3T3-L1 cells through sirtuin-1, peroxisome proliferator-activated receptor γ (PPAR γ), glucose transporter type 4 (GLUT-4) of (+)-catechin & proanthocyanidin fraction Uncaria gambir Roxb. Methods: Adipocytes differentiation activity of (+)-Catechin of Uncaria gambir Roxb. was determined by oil red O staining method & glucose uptake activity was determined by measuring 2-deoxyglucose uptake on 3T3-L1 cells. The ability of (+) - catechin as an activator of sirtuin-1 was assessed by administration of (+) - catechin with the presence of a specific inhibitor of sirtuin-1, nicotinamide. Metformin 1 mM & 5 mM were used as positive control. Sirtuin-1, PPAR γ & GLUT-4 expressions were determined by RT-PCR. Results: (+)-Catechin & proanthocyanidin fraction of Uncaria gambir Roxb. were found to increase adipocyte differentiation & glucose uptake by increasing activity of sirtuin-1 as well as metformin (P ≤0.05). PPAR γ, GLUT-4 and sirtuin-1 expressions were known to be responsible for this activities. Conclusion: These results indicate that (+)–catechin & proanthocyanidin fraction of Uncaria gambir Roxb. could be utilized as a renewable bioresource to develop potential antidiabetic and antiobesity agents.