Indole‐3‐carbinol (I3C), a naturally occurring compound found in cruciferous vegetables, and its metabolite 3,3′‐diindolylmethane (DIM) reduce body mass and serum glucose levels in high‐fat‐diet‐induced obese mice. This study aimed to determine whether I3C or DIM could increase glucose uptake via enhanced insulin sensitivity in 3T3‐L1 adipocytes, as well as the mechanism involved.
3T3‐L1 preadipocytes were differentiated by using a mixture of adipogenic inducers, including a suboptimal concentration of insulin.
DIM, but not I3C, increased adipocyte differentiation through upregulation of peroxisome proliferator‐activated receptor γ and CCAAT/enhancer‐binding protein α. DIM also enhanced glucose uptake by increasing expression of glucose transporter 4 in adipocytes. This was associated with DIM‐enhanced phosphorylation of the signaling intermediates Akt, insulin receptor substrate‐1, and insulin receptor early in differentiation.
Our findings suggest that DIM may improve insulin sensitivity through the activation of the insulin signaling pathway, leading to enhanced glucose uptake.