A new role for glucose-sensing neurons under torpor and hibernation

Q神经元诱导的低温和低代谢(QIH)已被报道引起低温和低代谢。我们发现，一旦动物进入QIH，血糖稳态就会迅速恢复，而新的稳态不会受到禁食的干扰，禁食对糖代谢有强烈的刺激作用。QIH动物表现出许多2型糖尿病的迹象，这表明这些动物存在葡萄糖代谢不足，处于“糖尿病样”状态。我们还发现，当体温升高时，QIH动物表现出正常的糖代谢。基础血糖、血浆胰岛素和全身糖代谢的差异完全取消。与此相一致的是，加热后QIH动物个体组织的葡萄糖代谢也明显增加。QIH小鼠存在胰岛素抵抗，提示可能是糖敏感神经元及其下游神经元受到QIH的干扰。我们对下丘脑几个核团的葡萄糖感觉进行了评估，发现在QIH过程中，葡萄糖感觉发生了变化。与上述结果一致，QIH动物加温后下丘脑的葡萄糖敏感性至少部分恢复。这些结果是在2023年日本生理学会的一次会议上公布的。

The Q-neuron-induced hypothermia and hypometabolism (QIH) has been reported to induce hypothermia and hypometabolism. We found that the glucose homeostasis is reset quickly once the animals entered QIH, and the new homeostasis was not disturbed by fasting, a strong stimulus on glucose metabolism. The QIH animals showed many indicators of type 2 diabetes, suggesting these animals had glucose hypometabolism and were under a “diabetes-like” state. We also found that the QIH animals shows normal glucose metabolism when the body temperature was heating up. The differences of basal blood glucose, plasma insulin, and systemic glucose metabolism are fully abolished. In line with these, glucose metabolism from individual tissues of QIH animals were also clearly increase after heating up. The insulin resistance of QIH mice suggests that glucose-sensing neuron or its downstream neurons may be disturbed by QIH. We have evaluated the glucose-sensing on several hypothalamic nuclei and found the glucose-sensing was altered during QIH. In line with the above results, the glucose sensitivity of hypothalamus was at least partially recovered when the QIH animals were heating up. These results were presented at a meeting of the Japanese Physiological Society in 2023.