Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto, Japan.
Nat Metab. 2021 Feb;3(2):196-210. doi: 10.1038/s42255-021-00342-6. Epub 2021 Feb 18.
Ketone bodies are generated in the liver and allow for the maintenance of systemic caloric and energy homeostasis during fasting and caloric restriction. It has previously been demonstrated that neonatal ketogenesis is activated independently of starvation. However, the role of ketogenesis during the perinatal period remains unclear. Here, we show that neonatal ketogenesis plays a protective role in mitochondrial function. We generated a mouse model of insufficient ketogenesis by disrupting the rate-limiting hydroxymethylglutaryl-CoA synthase 2 enzyme gene (Hmgcs2). Hmgcs2 knockout (KO) neonates develop microvesicular steatosis within a few days of birth. Electron microscopic analysis and metabolite profiling indicate a restricted energy production capacity and accumulation of acetyl-CoA in Hmgcs2 KO mice. Furthermore, acetylome analysis of Hmgcs2 KO cells revealed enhanced acetylation of mitochondrial proteins. These findings suggest that neonatal ketogenesis protects the energy-producing capacity of mitochondria by preventing the hyperacetylation of mitochondrial proteins.
酮体在肝脏中产生,可在禁食和热量限制期间维持全身热量和能量稳态。先前已经证明,新生儿酮体生成独立于饥饿而被激活。然而,酮体生成在围产期的作用尚不清楚。在这里,我们表明新生儿酮体生成在维持线粒体功能方面起着保护作用。我们通过破坏限速酶羟甲基戊二酰辅酶 A 合酶 2 基因(Hmgcs2),生成了一种酮体生成不足的小鼠模型。Hmgcs2 敲除(KO)新生儿在出生后几天内会发展为微小泡性脂肪变性。电子显微镜分析和代谢物分析表明,Hmgcs2 KO 小鼠的能量产生能力受到限制,乙酰辅酶 A 积累。此外,Hmgcs2 KO 细胞的乙酰组分析显示线粒体蛋白的乙酰化增强。这些发现表明,新生儿酮体生成通过防止线粒体蛋白的过度乙酰化来保护线粒体的能量产生能力。