Low Dose of Curcumin Combined with Exercise Synergistically Induces Beige Adipocyte Formation in Mice

Curcumin (Cur) has various biological effects, including anti-obesity and anti-diabetic properties. However, the molecular mechanisms by which Cur exerts these effects remain unclear. In addition, high doses of Cur have been administered in most animal and human trials to date, due mainly to the poor water solubility of native Cur and its low oral bioavailability. In our previous study, we demonstrated that a highly bioavailable Cur formulation (4.5 mg/kg) induces the formation of beige adipocytes in inguinal white adipose tissue (iWAT) in mice. In the present study, to enhance Cur-mediated beige adipocyte formation and reduce the required functional Cur dose, we investigated whether a low dose of Cur combined with exercise synergistically induced beige adipocyte formation. Cur (1.5 mg Cur/kg, daily) combined with exercise for 4 wk significantly induced beige adipocyte formation in iWAT in mice. This effect was associated with the elevation of interleukin-6 level following subsequent Cur administration combined with exercise. These results indicate that exercise combined with Cur synergistically enhances biological activity and reduces the required Cur dose. These findings suggest that Cur could be used as a dietary supplement during exercise to enhance exercise-mediated health benefits.