炎症诱导的氧化通过降低脂肪细胞中Sp1转录活性来抑制PPARα的表达和功能
Jungin Kwon1, Yumeko Aoki1, Haruya Takahashi1
1Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011, Japan.
Biochimica et biophysica acta. Gene regulatory mechanisms
|September 22, 2023
概括
氧化 (NO) 通过抑制Sp1活性,抑制脂肪细胞中氧酶增殖器激活受体α (PPARα) 基因表达. 这种机制可能解释了肥胖和炎症中PPARα的减少.
科学领域:
- 分子生物学分子生物学
- 代谢调节 代谢调节 代谢调节
- 细胞信号传递 细胞信号传递
背景情况:
- 过氧体增殖器激活受体α (PPARα) 的激活可以治疗高脂血症.
- 在肥胖期间,PPARα基因表达在脂肪组织中减少,但机制尚不清楚.
- 氧化 (NO) 参与炎症和代谢过程.
研究的目的:
- 阐明NO影响脂肪细胞中PPARα基因表达的分子机制.
- 研究Sp1 (特异性蛋白1) 在NO介导PPARα调节中的作用.
- 探索这种机制在炎症状况和肥胖中的相关性.
主要方法:
- 在体外研究中,使用使用NO供体或脂聚糖 (LPS) 治疗的10T1/2脂肪细胞.
- 使用急性和慢性炎症小鼠模型的体内研究.
- 药理上抑制氧化合成酶2 (NOS2) 和内质网膜 (ER) 压力.
- 促进体突变和染色体免疫沉降 (ChIP) 试验用于评估Sp1结合.
主要成果:
- NO抑制了小鼠脂肪细胞和白脂肪组织 (WAT) 中的PPARαmRNA表达.
- NOS2抑制减弱了PPARα的NO诱导抑制.
- 经期应激抑制剂部分挽救了PPARα的NO诱导抑制.
- NO降低了Sp1与PPARα促进体的结合,可能是通过降低Sp1的表达.
结论:
- 氧化通过抑制Sp1转录活性来抑制脂肪细胞中的PPARα基因表达.
- 这种NO介导的途径提供了在炎症和潜在的肥胖期间在WAT中PPARα下调的分子机制.
- 准NO信号可能为与PPARα失调相关的代谢障碍提供治疗策略.
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