紫光抑制热生成由素5下丘脑神经元
Kevin X Zhang1,2,3,4, Shane D'Souza1,2,3, Brian A Upton1,2,3,4
1The Visual Systems Group, Abrahamson Pediatric Eye Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
Nature
|September 4, 2020
概括
紫光激活了一个涉及下丘脑中Opsin 5 (OPN5) 神经元的深层大脑通路. 这种途径通常抑制棕色脂肪组织 (BAT) 热生成,调节体温.
科学领域:
- 神经科学
- 生理学
- 生物化学
背景情况:
- 奥普辛是与G蛋白结合的受体,在动物中作为光探测器起作用.
- 奥普辛5 (OPN5) 是一种对可见紫光敏感的保守奥普辛.
- 在视网膜,皮肤,尤其是下丘脑前视区域 (POA) 中发现了OPN5.
研究的目的:
- 为了研究大脑中的新光传感途径.
- 确定OPN5在下丘脑前视区域 (POA) 在温度调节中的作用.
- 阐明OPN5影响棕色脂肪组织 (BAT) 活动的机制.
主要方法:
- 在POA神经元中对OPN5的表达分析.
- 对表达OPN5的POA神经元进行化学刺激.
- 在寒冷条件下对OPN5-null小鼠进行表型分析.
- 紫光光刺激实验
- 在体外测量细胞内cAMP水平.
主要成果:
- OPN5在质感应热感应神经元中表达.
- 表达OPN5的POA神经元投射并抑制BAT活动.
- OPN5零小鼠表现出过度活跃的BAT,体温升高和过度发热.
- 紫光刺激在野生类型的小鼠中急性抑制了BAT温度,但不是OPN5-null.
- 紫光增加了OPN5表达POA神经元中的cAMP.
结论:
- 一个涉及POA中的OPN5的深层大脑紫色光敏感光受体通路调节了BAT热生成.
- 这种途径通常会抑制BAT活动.
- 在POA中OPN5代表了调节体温和能量消耗的新目标.
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