Graduate Program in Biochemical and Molecular Nutrition, Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA 02111, USA.
Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA.
Cell Rep. 2017 Dec 5;21(10):2737-2747. doi: 10.1016/j.celrep.2017.11.048.
The central mechanisms controlling glucose and lipid homeostasis are inadequately understood. We show that α2δ-1 is an essential regulator of glucose and lipid balance, acting in steroidogenic factor-1 (SF1) neurons of the ventromedial hypothalamus (VMH). These effects are body weight independent and involve regulation of SF1 neuronal activity and sympathetic output to metabolic tissues. Accordingly, mice with α2δ-1 deletion in SF1 neurons exhibit glucose intolerance, altered lipolysis, and decreased cholesterol content in adipose tissue despite normal energy balance regulation. Profound reductions in the firing rate of SF1 neurons, decreased sympathetic output, and elevated circulating levels of serotonin are associated with these alterations. Normal calcium currents but reduced excitatory postsynaptic currents in mutant SF1 neurons implicate α2δ-1 in the promotion of excitatory synaptogenesis separate from its canonical role as a calcium channel subunit. Collectively, these findings identify an essential mechanism that regulates VMH neuronal activity and glycemic and lipid control and may be a target for tackling metabolic disease.
中央机制控制葡萄糖和脂质稳态理解不足。我们表明,α2δ-1 是葡萄糖和脂质平衡的重要调节剂,作用于腹内侧下丘脑 (VMH) 的甾体生成因子-1 (SF1) 神经元。这些影响与体重无关,涉及 SF1 神经元活性和交感神经输出到代谢组织的调节。因此,SF1 神经元中 α2δ-1 缺失的小鼠表现出葡萄糖不耐受、脂解改变和脂肪组织胆固醇含量降低,尽管能量平衡调节正常。SF1 神经元放电率显著降低、交感神经输出减少和循环中血清素水平升高与这些改变有关。正常的钙电流但减少兴奋性突触后电流在突变 SF1 神经元中暗示 α2δ-1 在促进兴奋性突触发生中的作用与其作为钙通道亚基的典型作用分开。总的来说,这些发现确定了一种调节 VMH 神经元活性和血糖和脂质控制的基本机制,可能是治疗代谢疾病的靶点。