In vitro Evidence

Curcumin activates AMPK and suppresses gluconeogenic gene expression in hepatoma cells
Biochem Biophys Res Commun. 2009;388(2):377-82
Over 23 million people in the United States and 250 million people across the world are affected by diabetes, a group of metabolic chronic disease, which is characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both.

Since time immemorial, number of plants and their derivatives with purported anti-diabetic properties has been used in folk medicine, traditional healing systems, and even as complementary and alternative therapy. Several botanical, herbal and biological products have been shown to lower blood glucose or decrease complications related to diabetes.

For centuries, Curcuma longa (Turmeric) has been widely used in indigenous medicine for the treatment of a variety of inflammatory conditions and other diseases, including diabetes. Several researchers have showed that Curcumin and Tetrahydrocurcumin are effective against diabetes by lowering blood glucose levels. Curcumin has also been known to play a protective role against nephropathy, retinopathy and islet damage in rodents. However, there is still a lack of clarity on the mechanism of action at molecular level in mediating the glucose-lowering action.
Objective:

To study the effects of Curcumin, Curcumin C3 Complex® and Tetrahydrocurcuminoids (THCs) on metabolic targets which modulate insulin action, at concentrations comparable to its bioavailability.

Study Design:

Hep3B human hepatoma cells and H4IIE rat hepatoma cells were cultured according to the standard procedure. Different parameters including insulin receptor tyrosine kinase activity, glucose uptake, α-glucosidase and dipeptidyl peptidase-4 inhibitory activity were evaluated.

Results:
  • Curcuminoids did not improve in vitro IR-TK activity either in the presence or absence of insulin
  • Curcuminoids did not inhibit α-glucosidase activity or dipeptidyl protease-4 activity
  • Curcuminoids suppressed dexamethasone-induced gluconeogenic gene expression in a dose-dependent manner
Conclusion

This novel mechanism of action, along with its well-characterized anti-oxidant and anti-inflammatory properties, its tolerability and promising findings suggested that Curcuminoids may offer a complementary approach in the management of diabetes.