Max Planck Institute of Immunobiology and Epigenetics, Stuebeweg 51, D-79108 Freiburg, Germany.
Cell. 2012 Oct 12;151(2):414-26. doi: 10.1016/j.cell.2012.09.021.
Diabetes, obesity, and cancer affect upward of 15% of the world's population. Interestingly, all three diseases juxtapose dysregulated intracellular signaling with altered metabolic state. Exactly which genetic factors define stable metabolic set points in vivo remains poorly understood. Here, we show that hedgehog signaling rewires cellular metabolism. We identify a cilium-dependent Smo-Ca(2+)-Ampk axis that triggers rapid Warburg-like metabolic reprogramming within minutes of activation and is required for proper metabolic selectivity and flexibility. We show that Smo modulators can uncouple the Smo-Ampk axis from canonical signaling and identify cyclopamine as one of a new class of "selective partial agonists," capable of concomitant inhibition of canonical and activation of noncanonical hedgehog signaling. Intriguingly, activation of the Smo-Ampk axis in vivo drives robust insulin-independent glucose uptake in muscle and brown adipose tissue. These data identify multiple noncanonical endpoints that are pivotal for rational design of hedgehog modulators and provide a new therapeutic avenue for obesity and diabetes.
糖尿病、肥胖症和癌症影响着全球超过 15%的人口。有趣的是,这三种疾病都存在细胞内信号失调与代谢状态改变的情况。确切地说,哪些遗传因素决定了体内稳定的代谢平衡点仍知之甚少。在这里,我们展示了 hedgehog 信号通路会重新编排细胞的代谢方式。我们发现了一个依赖纤毛的 Smo-Ca(2+)-Ampk 轴,它可以在激活后几分钟内引发快速的类似瓦堡样代谢重编程,这对于适当的代谢选择性和灵活性是必需的。我们表明 Smo 调节剂可以将 Smo-Ampk 轴与经典信号脱耦,并鉴定出环巴胺是一类新的“选择性部分激动剂”,能够同时抑制经典 hedgehog 信号和激活非经典 hedgehog 信号。有趣的是,体内 Smo-Ampk 轴的激活可以在肌肉和棕色脂肪组织中驱动强大的胰岛素非依赖性葡萄糖摄取。这些数据确定了多个对 hedgehog 调节剂的合理设计至关重要的非经典终点,并为肥胖症和糖尿病提供了新的治疗途径。