Dr. Cheng Zhan et al. revealed how the brain regulates blood glucose levels during stress

On June 15th 2017，Dr. Cheng Zhan et al. published a paper entitled “A Central Catecholaminergic Circuit Controls Blood Glucose Levels during Stress” in Neuron. The authors studied the neural mechanisms underlying stress-induced hyperglycemia, and identified a key neural circuit, the PVN (Hypothalamic paraventricular nucleus)-VLM (Ventral lateral medulla)-Spinal cord, which mediates stress-induced hyperglycemia in mice.

Glucose is the main energy source for mammals. When facing significant threats (stressors), glucose stores are mobilized, resulting in a rapid elevation of blood glucose levels. This process, referred to as stress-induced hyperglycemia, is well accepted as a fundamental adaptive response to threats. Despite its importance, relatively little is known about the neural circuitry that controls this adaptive response.

The authors applied both restraint, footshock, and Lipopolysaccharide stress experimental models and a state-of-the-art cell-type-specific ablation approach to survey the roles of three different populations, and found that only the VLM CA neuron population is required in controlling stress-induced hyperglycemia. Moreover, they found that the selective activation of VLM CA neurons induced hyperglycemia, and determined that descending neuronal projections to the spinal cord are sufficient for this induction. They then mapped the whole-brain monosynaptic inputs of VLM CA neurons and found that the PVN-VLM circuit increased blood glucose levels. The major scientific implication of this study is a considerably deeper understanding of the mechanisms in the brain that control energy metabolism, particularly during periods when animals are under stress. This is important because the majority of studies in this field have to date focused on animals in a resting state.

Zhe Zhao, Liang Wang, and Wenling Gao, who are technicians from the Imaging Facility of NIBS, are the co-first authors of this paper. Cheng Zhan is the corresponding author of this study. The other authors are Fei Hu, Juen Zhang, Yuqi Ren, Rui Lin, Qiru Feng, Minmin Luo (of Prof. M.M. Luo’s lab at NIBS); Mingxiu Cheng and Sen Song (of Prof. S. Song’s lab at Tsinghua University); Dapeng Ju (of E.Q. Zhang’s lab at NIBS); Qingsheng Chi and Dehua Wang (of the Institute of Zoology, CAS). This study was funded by MOST, NSFC, and the Beijing Municipal Government. The great majority of the work for this study was conducted at the National Institute of Biological Sciences, Beijing.