在胰腺β细胞中,内质网膜应激会通过ATF4介导的PDE4D表达引发因克雷丁脱敏和β细胞功能障碍
Ji-Hye Lee1,2, Hanguk Ryu1, Hyejin Lee1
1Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea.
American journal of physiology. Endocrinology and metabolism
|September 20, 2023
概括
在2型糖尿病 (T2D) 中,胰腺β细胞功能通过PERK-ATF4通路受到内质网膜应激损害. 这项研究表明,ATF4可以调节PDE4D,减少cAMP信号传递,导致β细胞衰竭,这是T2D治疗的可向途径.
科学领域:
- 内分泌学和新陈代谢学
- 细胞和分子生物学 细胞和分子生物学
- 糖尿病研究 糖尿病研究
背景情况:
- 胰腺β细胞功能障碍和损失是2型糖尿病 (T2D) 进展的核心.
- 细胞内膜网膜 (ER) 应激,特别是通过PERK-ATF4通路,与β细胞病理有关.
- 连接ER压力与β细胞功能障碍的精确分子机制仍然不完全理解.
研究的目的:
- 阐明PERK-ATF4途径调解β细胞功能障碍的分子事件.
- 研究ATF4在调节4D化酶 (PDE4D) 表达和cAMP信号传递中的作用.
- 评估在T2D中准ATF4-PDE4D途径的治疗潜力.
主要方法:
- 产生的β细胞特异性转基因小鼠过度表达ATF4.4.
- 使用了缺少叶丁受体 (db/db) 的T2D小鼠模型.
- 通过药理抑制ATF4通路和PDE4活动.
- 评估了β细胞功能,胰岛素分泌和cAMP信号传递.
主要成果:
- 在β细胞中ATF4的过度表达模仿了加速T2D表型,包括功能障碍和损失.
- 而ATF4,而不是CHOP,直接促进了PDE4D的表达,导致cAMP信号的减少和失效的胰岛素/葡萄糖反应.
- 糖尿病db/db小鼠表现出高核ATF4和PDE4D表达,与β细胞功能受损相关.
- 药理上抑制ATF4或PDE4改善了db/db和ATF4转基因小鼠的葡萄糖耐受性和胰岛素分泌.
结论:
- 在T2D中,ER压力通过ATF4介导的PDE4D升调促进β细胞衰竭.
- ATF4-PDE4D轴通过降低cAMP信号调节来破坏β细胞功能.
- 向ATF4-PDE4D通路代表了一种有前途的治疗策略,用于在T2D中保存β细胞功能.
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