微RNA 29通过底层的miR-29-OXPHOS复杂通路调节β细胞线粒体代谢和胰岛素分泌
E Cowan1, J Sun2, A Hamilton1,3
1Unit of Islet Cell Exocytosis, Department of Clinical Sciences Malmö, Lund University Diabetes Centre, Lund University, Lund, Sweden.
Acta physiologica (Oxford, England)
|May 27, 2024
概括
微RNA-29 (miR-29) 在调节β细胞线粒体功能和胰岛素分泌方面发挥着至关重要的作用. 减少miR-29表达增强了胰岛素分泌,可能作为葡萄糖毒性的补偿机制.
科学领域:
- 内分泌学 在内分泌学.
- 分子生物学分子生物学
- 线粒体生物学 线粒体生物学
背景情况:
- 微RNAs (miRNAs) 是β细胞功能的关键调节者.
- 线粒体功能障碍和胰岛素分泌受损是糖尿病的特征.
- 鉴定参与β细胞线粒体代谢的关键miRNA是必不可少的.
研究的目的:
- 确定调节β细胞线粒体代谢的关键miRNAs.
- 为了阐明新的β细胞miRNA-线粒体通路.
- 研究miR-29在β细胞功能和线粒体活动中的作用.
主要方法:
- 使用TargetScan. 的miRNA-目标相互作用的生物信息预测.
- 在不同的葡萄糖条件下测量INS-1 832/13细胞中的miRNA表达和胰岛素分泌.
- 在miR-29沉默细胞中评估胰岛素分泌,线粒体复合物I基因表达和氧化酸化 (OXPHOS).
- 从糖尿病模型 (GK大鼠,db/db小鼠) 和人类2型糖尿病 (T2D) 岛屿中评估miR-29表达.
主要成果:
- 预计miR-29,miR-15和miR-124将准线粒体的cis-eGenes,miR-29将准至少12个.
- 在高葡萄糖培养的细胞中观察到减少miR-29表达和胰岛素分泌.
- MiR-29敲击增强了胰岛素分泌,线粒体综合体I和II表达,以及OXPHOS.
- 在不同的糖尿病模型和疾病中,MiR-29表达模式有所不同.
结论:
- MiR-29是通过miR-29-OXPHOS途径进行β细胞线粒体代谢和胰岛素分泌的关键调节者.
- 减少miR-29表达似乎是一种补偿机制,在葡萄糖毒性下增强胰岛素分泌.
- 这些发现突出了miR-29作为糖尿病的潜在治疗点.
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