在禁食期间调节适应性行为,通过下丘脑Foxa2进行调节
Jose P Silva1, Ferdinand von Meyenn, Jessica Howell
1The Rockefeller University, Laboratory of Metabolic Diseases, 1230 York Avenue, New York, New York 10021, USA.
Nature
|December 4, 2009
概括
叉头盒转录因子Foxa2通过控制素和黑色素缩激素 (MCH) 表达来调节养行为. 这种转录因子作为大脑中的代谢传感器,影响食物摄入和代谢.
科学领域:
- 神经科学是一个神经科学.
- 代谢调节 代谢调节 代谢调节
- 分子生物学分子生物学
背景情况:
- 侧面的下丘脑区域是一个关键的大脑区域,用于调节养行为,兴奋和有动机的行为.
- 素和黑色素缩激素 (MCH) 是横向下丘脑中的神经,通过食被抑制,并在禁食期间释放.
- 整合与食相关的信号和神经表达的精确分子机制尚不清楚.
研究的目的:
- 调查转录因子Foxa2在侧向下丘脑中调节素和MCH表达中的作用.
- 阐明胰岛素信号如何影响Foxa2活性和随后的神经的表达.
- 确定Foxa2操纵对养行为,新陈代谢和葡萄糖平衡的影响.
主要方法:
- 利用小鼠的基因操纵来研究Foxa2功能,包括构成性和条件激活模型.
- 研究了Foxa2与MCH和素基因的促进体的结合.
- 评估了Foxa2激活对食物消耗,身体组成,身体活动和胰岛素敏感性的影响.
主要成果:
- 通过与它们的促进体结合,Foxa2直接调节素和MCH的表达.
- 胰岛素信号促进了Foxa2的核排斥,降低了和肥胖状态下的MCH和素表达.
- 构成性或条件激活Foxa2增加了MCH和素的表达,导致增加食物摄入量,新陈代谢和胰岛素敏感性,以及增加体力活动.
结论:
- 福克萨2在侧面的下丘脑区域作为一个关键的代谢传感器.
- 福克萨2集成了代谢信号来调节养行为,能量消耗和生理反应.
- 向Foxa2可能为肥胖和糖尿病等代谢障碍提供治疗潜力.
相关概念视频
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01:16Hormones Regulating Blood Glucose
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