Activation of AMPK by berberine promotes adiponectin multimerization in 3T3-L1 adipocytes.

Adiponectin is assembled into trimer (LMW), hexamer (MMW) and high-molecular-weight (HMW) multimer in adipocytes. The HMW adiponectin is more metabolically active and closely associated with peripheral insulin sensitivity. In this study, we reported that berberine, an isoquinoline alkaloid with insulin-sensitizing effect, inhibits the expression of adiponectin, but promotes the assembly of HMW adiponectin and increases the ratio of HMW to total adiponectin. Berberine activates AMPK. Knockdown of AMPKα1 abolishes the effect of berberine. Activation of AMPK by AICAR also increases the level of HMW adiponectin. Our study suggested that activation of AMPK by berberine promotes adiponectin multimerization.