Department of Cellular Regenerative Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan.
Louis Pasteur Center for Medical Research, 103-5 Tanaka-Monzen-cho, Sakyo-ku, Kyoto, 606-8225, Japan.
Sci Rep. 2024 May 11;14(1):10789. doi: 10.1038/s41598-024-61774-0.
Brown adipocytes are potential therapeutic targets for the prevention of obesity-associated metabolic diseases because they consume circulating glucose and fatty acids for heat production. Angiotensin II (Ang II) peptide is involved in the pathogenesis of obesity- and cold-induced hypertension; however, the mechanism underlying the direct effects of Ang II on human brown adipocytes remains unclear. Our transcriptome analysis of chemical compound-induced brown adipocytes (ciBAs) showed that the Ang II type 1 receptor (AGTR1), but not AGTR2 and MAS1 receptors, was expressed. The Ang II/AGTR1 axis downregulated the expression of mitochondrial uncoupling protein 1 (UCP1). The simultaneous treatment with β-adrenergic receptor agonists and Ang II attenuated UCP1 expression, triglyceride lipolysis, and cAMP levels, although cAMP response element-binding protein (CREB) phosphorylation was enhanced by Ang II mainly through the protein kinase C pathway. Despite reduced lipolysis, both coupled and uncoupled mitochondrial respiration was enhanced in Ang II-treated ciBAs. Instead, glycolysis and glucose uptake were robustly activated upon treatment with Ang II without a comprehensive transcriptional change in glucose metabolic genes. Elevated mitochondrial energy status induced by Ang II was likely associated with UCP1 repression. Our findings suggest that the Ang II/AGTR1 axis participates in mitochondrial thermogenic functions via glycolysis.
棕色脂肪细胞是预防肥胖相关代谢性疾病的潜在治疗靶点,因为它们可以消耗循环中的葡萄糖和脂肪酸来产热。血管紧张素 II(Ang II)肽参与肥胖和冷诱导性高血压的发病机制;然而,Ang II 对人棕色脂肪细胞的直接作用的机制尚不清楚。我们对化学化合物诱导的棕色脂肪细胞(ciBAs)的转录组分析表明,血管紧张素 II 型 1 受体(AGTR1),而不是 AGTR2 和 MAS1 受体,表达。Ang II/AGTR1 轴下调线粒体解偶联蛋白 1(UCP1)的表达。同时用β-肾上腺素能受体激动剂和 Ang II 处理会减弱 UCP1 的表达、甘油三酯脂解和 cAMP 水平,尽管 Ang II 通过蛋白激酶 C 途径主要增强 cAMP 反应元件结合蛋白(CREB)磷酸化。尽管脂解减少,但 Ang II 处理的 ciBAs 中的偶联和非偶联线粒体呼吸均增强。相反,Ang II 处理后糖酵解和葡萄糖摄取被强烈激活,而葡萄糖代谢基因的转录没有全面改变。Ang II 诱导的线粒体能量状态升高可能与 UCP1 抑制有关。我们的研究结果表明,Ang II/AGTR1 轴通过糖酵解参与线粒体产热功能。