Effect of selected Indian Medicinal Plants on PPARγ expression using 3T3 L1 Adipocytes as an In Vitro model

Abstract

Introduction: Azadirachta indica, Gymnema sylvestre, Momordica charantia, Syzygium cumini, and Trigonella
foenum-graecum are known for their antidiabetic effects; however, molecular mechanism/s have not been evaluated.
We have attempted to elucidate a possible mechanism, namely, effect on peroxisome proliferator-activated
receptor-g expression of these plant extracts using 3T3-L1 adipocytes. Materials and Methods: 3T3 L1 fibroblasts
were initially differentiated into adipocytes, following which RNA was extracted and reverse transcribed to cDNA
for evaluation of PPARγ expression. Relative expression was normalized using GAPDH. Relative messenger
RNA expression level was calculated according to ΔΔCT method and compared with Pioglitazone, a known
insulin sensitizer. Results: M. charantia, S. cumini, and G. sylvestre showed an increase in PPARγ expression as
compared to Control cells. Pioglitazone also showed ~2.5-fold increase in PPARγ expression. Of these three plant
extracts, hydroalcoholic extract of M. charantia showed maximum PPARγ expression with ~4.3-fold increase
which was statistically significant compared to control and reference standards. Discussion: Activation of PPARγ
leads in improvement of insulin sensitivity through binding of synthetic drugs resulting in a decrease in insulin and
glucose levels in patients with diabetes. Conclusion: Our data thus demonstrates that M. charantia, G. sylvestre,
and S. cumini can be considered as PPAR modulators, acting through the PPAR signaling pathway resulting in
enhanced transcription during adipocyte differentiation. This could be beneficial in the management of diabetes
and its long-term complications with lesser toxicities.