尼古丁信号刺激小鼠和人类胰腺α细胞中的葡萄糖分泌
Alexander Hamilton1,2,3, Quan Zhang1,4, Rui Gao1,5
1Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford and Churchill Hospital, Oxford, U.K.
Diabetes
|October 30, 2024
概括
尼古丁急性刺激胰腺α细胞中的,增加葡萄糖分泌. 这表明,尼古丁可能通过破坏葡萄糖调节来加剧胰岛素抵抗.
科学领域:
- 内分泌学 在内分泌学.
- 神经生物学 神经生物学 神经生物学
- 代谢研究研究 代谢研究
背景情况:
- 吸烟是已知的2型糖尿病的危险因素,与尼古丁诱导的胰岛素抵抗有关.
- 尼古丁对胰腺小岛激素分泌的直接影响尚不清楚.
- 尼古丁作为一种对离子体胆固醇受体的激动剂.
研究的目的:
- 为了研究尼古丁对胰腺小岛激素产生的急性调节.
- 检查尼古丁对细胞质动力学和阿尔法细胞中的葡萄糖分泌的影响.
- 为了比较尼古丁在α和β细胞中激活的信号通路.
主要方法:
- 焦显微镜在小鼠和人类小岛上图像细胞质 (Ca2+) 动态.
- 测量尼古丁的反应中孤立的小鼠岛屿的葡萄糖分泌.
- 通过细胞内二甲基糖醇水平评估metabotropic胆固醇信号传递.
主要成果:
- 尼古丁在约70%的葡萄糖分泌α细胞中急性刺激了细胞溶液Ca2+,但在胰岛素分泌β细胞中没有.
- 这种的增加与显著刺激葡萄糖分泌 (2.5倍) 相关联.
- 尼古丁诱导的升主要涉及细胞外流入,而阿尔法细胞和β细胞之间的metabotropic信号传递有所不同.
结论:
- 胰腺小岛激素的副交感调节涉及阿尔法 (离子和转基因) 和β (转基因) 细胞中不同的信号通路.
- 尼古丁对阿尔法细胞的作用微调了由乙胆诱导的葡萄糖外细胞.
- 持续的尼古丁刺激可以通过增加葡萄糖释放来减弱胰岛素敏感性.
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