脂肪组织中的压力信号通路调节肝脏的胰岛素抵抗
Guadalupe Sabio1, Madhumita Das, Alfonso Mora
1Howard Hughes Medical Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA.
概括
高脂肪饮食会激活c-Jun NH2终端激酶1 (JNK1),导致胰岛素抵抗. 向脂肪组织中的JNK1可以通过预防肝脏的胰岛素抵抗来治疗代谢综合征.
科学领域:
- 代谢性疾病是一种代谢性疾病.
- 分子生物学分子生物学
- 内分泌学 在内分泌学.
背景情况:
- 高脂肪饮食激活c-Jun NH2终端激酶1 (JNK1),这是一个关键调节器,与胰岛素抵抗有关.
- 胰岛素抵抗是代谢综合征的核心特征,这是一个增加心脏病,中风和2型糖尿病风险的疾病群.
- 脂肪组织中的JNK1信号传递是代谢障碍的潜在治疗点.
研究的目的:
- 研究脂肪组织JNK1在饮食引起的胰岛素抵抗中的特定作用.
- 阐明脂肪JNK1影响肝脏胰岛素敏感性的分子机制.
主要方法:
- 在脂肪组织中产生具有选择性JNK1基因切除的基因工程小鼠.
- 进行高脂肪饮食以评估饮食诱导的代谢变化.
- 分析胰岛素抵抗标记物,炎症性细胞因子表达和肝脏和脂肪组织中关键蛋白质信号通路.
主要成果:
- 脂肪组织中选择性的JNK1缺陷显著抑制了高脂肪饮食引起的肝脏胰岛素抵抗.
- 脂肪组织中的JNK1激活促进了互白素-6 (IL-6) 的分泌.
- 脂肪酸衍生的IL-6导致肝脏中抑制细胞因子信号传递3 (SOCS3) 的表达增加,这是已知的肝脏胰岛素抵抗的调解者.
结论:
- 脂肪组织中的JNK1激活是肝脏胰岛素抵抗的关键驱动因素.
- 准脂肪组织中JNK1信号传递是对抗代谢综合征和胰岛素耐药性的有前途的治疗策略.
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