College of Pharmacy, Chungbuk National University, Cheongju, Republic of Korea.
Obesity (Silver Spring). 2018 Jul;26(7):1153-1160. doi: 10.1002/oby.22145. Epub 2018 May 3.
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.
吲哚-3-甲醇（I3C）是十字花科蔬菜中天然存在的一种化合物，其代谢产物 3,3′-二吲哚甲烷（DIM）可降低高脂肪饮食诱导肥胖小鼠的体重和血清葡萄糖水平。本研究旨在确定 I3C 或 DIM 是否可以通过增强胰岛素敏感性来增加 3T3-L1 脂肪细胞中的葡萄糖摄取，以及涉及的机制。
使用包括低浓度胰岛素在内的混合脂肪生成诱导剂将 3T3-L1 前脂肪细胞分化。
DIM 而非 I3C 通过上调过氧化物酶体增殖物激活受体γ和 CCAAT/增强子结合蛋白α 促进脂肪细胞分化。DIM 还通过增加脂肪细胞中葡萄糖转运蛋白 4 的表达来增强葡萄糖摄取。这与 DIM 增强分化早期胰岛素信号转导中间物 Akt、胰岛素受体底物-1 和胰岛素受体的磷酸化有关。
我们的研究结果表明，DIM 可能通过激活胰岛素信号通路来改善胰岛素敏感性，从而增强葡萄糖摄取。
