National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center for Biotherapy, Chengdu 610041, PR China.
Key Laboratory of Transplant Engineering and Immunology, West China Hospital, Sichuan University, Chengdu 610041, China.
Neuropharmacology. 2019 Apr;148:377-393. doi: 10.1016/j.neuropharm.2017.10.001. Epub 2017 Oct 4.
The brain is a high energy-consuming organ that typically utilizes glucose as the main energy source for cerebral activity. When glucose becomes scarce under conditions of stress, ketone bodies, such as β-hydroxybutyrate, acetoacetate and acetone, become extremely important. Alterations in brain energy metabolism have been observed in psychostimulant abusers; however, the mode of brain metabolic programming in cocaine dependence remains largely unknown. Here, we profiled the metabolites and metabolic enzymes from brain nucleus accumbens (NAc) of mice exposed to cocaine. We found that cocaine modified energy metabolism and markedly activated ketogenesis pathway in the NAc. The expression of HMG-CoA synthase 2 (HMGCS2), a critical rate-limiting ketogenesis enzyme, was markedly up-regulated. After switching metabolic pathways from ketogenesis to glycolysis through activation of glucokinase, cocaine-evoked metabolic reprogramming regained homeostasis, and the cocaine effect was attenuated. Importantly, both the pharmacological and genetic inhibition of HMGCS2 significantly suppressed cocaine-induced ketogenesis and behavior. In conclusion, cocaine induces a remarkable energy reprogramming in the NAc, which is characterized by HMGCS2-driven ketogenesis. Such effect may facilitate adaptations to cocaine-induced energy stress in the brain. Our findings establish an important link between drug-induced energy reprogramming and cocaine effect, and may have implication in the treatment of cocaine addiction.
大脑是一个高能耗器官,通常利用葡萄糖作为大脑活动的主要能量来源。当应激条件下葡萄糖变得稀缺时,酮体(如β-羟丁酸、乙酰乙酸和丙酮)就变得极其重要。在使用精神兴奋剂的人身上观察到了大脑能量代谢的改变;然而,可卡因依赖的大脑代谢编程模式在很大程度上仍然未知。在这里,我们对暴露于可卡因的小鼠伏隔核(NAc)中的代谢物和代谢酶进行了分析。我们发现可卡因改变了 NAc 中的能量代谢,并显著激活了酮体生成途径。酮体生成的关键限速酶 HMG-CoA 合酶 2(HMGCS2)的表达显著上调。通过激活葡萄糖激酶将代谢途径从酮体生成转变为糖酵解后,可卡因引起的代谢重编程恢复了平衡,可卡因的作用减弱。重要的是,HMGCS2 的药理学和遗传抑制均显著抑制了可卡因诱导的酮体生成和行为。总之,可卡因在 NAc 中诱导了显著的能量重编程,其特征是 HMGCS2 驱动的酮体生成。这种效应可能有助于大脑适应可卡因引起的能量应激。我们的发现建立了药物诱导的能量重编程与可卡因效应之间的重要联系,并可能对可卡因成瘾的治疗具有启示作用。