Central Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University. Beijing Maternal and Child Health Care Hospital, Beijing, 100026, China.
College of Kinesiology and Health, Capital University of Physical Education and Sports, Beijing, China.
Biochimie. 2023 Jun;209:85-94. doi: 10.1016/j.biochi.2023.02.004. Epub 2023 Feb 9.
Diet-induced obesity in mice and humans is commonly associated with an imbalance between energy intake and expenditure. Reportedly, creatine can enhance energy expenditure in brown adipose tissue and reduce hepatic triglycerides accumulation; however, the molecular mechanism underlying the role of exogenous creatine supplementation in regulating lipid droplet mobilization remains elusive. Herein, we employed a high-fat diet (HFD)- induced mouse model to investigate the role of creatine in regulating lipolysis and lipophagy in brown adipose tissue and the liver. Exogenous creatine supplementation ameliorated HFD-induced obesity, increased insulin sensitivity and improved glucose homeostasis. Creatine supplementation enhanced the expression of uncoupling protein 1 (UCP1), cell death-inducing DNA fragmentation factor alpha-like effector A (CIDEA), and other brown adipose tissue-specific thermogenic genes Cpt1a, Gyk, and Pgc1β in brown adipose tissue. Furthermore, creatine inhibited the expression of CIDEA, which promotes hepatic lipid accumulation. Creatine stimulated the expression of triglyceride lipase adipose triglyceride lipase, and phospho-hormone-sensitive lipase (HSL) induced increased lipolysis in brown adipose tissue and the liver. Meanwhile, reduced LC3B expression was accompanied by an increased level of p62 in HFD-fed mice, indicating diminished basal autophagy in brown adipose tissue and the liver; however, creatine enhanced P62/LC3B induced lipophagy in brown adipose tissue and the liver. Collectively, our results suggest that creatine may function as a brown adipose tissue activator to increase whole-body energy metabolism via coordinated lipolysis and lipophagy in brown adipose tissue and the liver.
饮食诱导的肥胖症在小鼠和人类中通常与能量摄入和消耗之间的失衡有关。据报道,肌酸可以增强棕色脂肪组织中的能量消耗并减少肝脏甘油三酯的积累;然而,外源性肌酸补充调节脂滴动员的分子机制仍不清楚。在此,我们采用高脂肪饮食(HFD)诱导的小鼠模型来研究肌酸在调节棕色脂肪组织和肝脏中的脂肪分解和脂自噬中的作用。外源性肌酸补充改善了 HFD 诱导的肥胖,增加了胰岛素敏感性并改善了葡萄糖稳态。肌酸补充增强了棕色脂肪组织中解偶联蛋白 1(UCP1)、细胞死亡诱导 DNA 片段化因子α样效应物 A(CIDEA)和其他棕色脂肪组织特异性产热基因 Cpt1a、Gyk 和 Pgc1β的表达。此外,肌酸抑制了 CIDEA 的表达,促进了肝脏脂质的积累。肌酸刺激甘油三酯脂肪酶脂肪甘油三酯脂肪酶和磷酸化激素敏感脂肪酶(HSL)的表达,诱导棕色脂肪组织和肝脏中的脂肪分解增加。同时,在 HFD 喂养的小鼠中,LC3B 表达减少伴随着 p62 水平升高,表明棕色脂肪组织和肝脏中的基础自噬减少;然而,肌酸增强了 P62/LC3B 诱导的棕色脂肪组织和肝脏中的脂自噬。总的来说,我们的结果表明肌酸可能作为一种棕色脂肪组织激活剂,通过协调棕色脂肪组织和肝脏中的脂肪分解和脂自噬来增加全身能量代谢。
Mol Metab. 2020-10
Physiol Behav. 2014-2-10