氧化和ER压力是因胰岛素生物合成和棕酸在胰岛素生成细胞中的增加而产生的
Brenda Vidrio-Huerta1, Thomas Plötz1, Stephan Lortz1
1Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
Journal of molecular endocrinology
|December 6, 2023
概括
在早期的2型糖尿病 (T2DM) 中,高胰岛素需求会导致内分泌网膜 (ER) 压力和细胞损伤. 将其与棕酸相结合,会加速功能障碍并触发细胞亡,强调减少胰岛素需求的必要性.
科学领域:
- 细胞生物学 细胞生物学
- 内分泌学 在内分泌学.
- 代谢疾病 代谢疾病
背景情况:
- 早期的2型糖尿病 (T2DM) 涉及胰岛素抵抗,因胰岛素分泌增加而得到补偿.
- 工作负载假设表明持续高胰岛素需求导致β细胞功能障碍和死亡.
- 由葡萄糖/脂质毒性加剧的内质网膜 (ER) 应激,与此过渡有关.
研究的目的:
- 研究过度胰岛素折叠对ER光H2O2生成,ER应激和细胞活力的影响.
- 为了检查高胰岛素和棕酸 (PA) 对胰腺β细胞功能的联合作用.
主要方法:
- 胰岛素在RINm5F细胞中表达,使用多克西环素调节的Tet-On系统.
- 使用光传感器蛋白TriPer.2量化ER光H2O2.
- 提高胰岛素表达和棕酸对细胞活力,ER压力和亡的影响进行了评估.
主要成果:
- 单独增加胰岛素表达就增加了ER光H2O2,并降低了细胞活力,但没有诱导细胞亡.
- 结合胰岛素表达和棕酸显著增加了ER压力,细胞亡和细胞死亡.
- ER局部化的催化酶表达证实了H2O2检测特异性,但没有减轻ER压力或细胞死亡.
结论:
- 单独高胰岛素可以诱导ER光H2O2,轻度ER压力,并降低活力.
- 超胰岛素与棕酸结合加快β细胞功能障碍并触发亡.
- 在早期T2DM中降低高胰岛素需求对于预防由葡萄糖/脂毒性引起的β细胞损伤至关重要.
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