基于代谢组学对氯胺酮引起的机体代谢特征及毒性机制研究

Ketamine abuse has become a global social problem. Conventional determination of ketamine and its metabolites was usually conducted under short-term drug usage situation. Metabolomics can be used to reveal the correlation between the metabolome and the pathophysiological changes in organism via the analyses of endogenous small-molecule metabolites, which may open a new avenue for elucidating the mechanisms of toxicity and addiction caused by ketamine. Based on our previous studies showing that the metabolome in ketamine addictive animals was altered, we propose to investigate the metabolome in rats that are exposed to ketamine without or with addiction to it by using NMR, LC/Mass spectrometry, and combining with pattern recognition and computer analysis. It is expected that a "metabolome-effect" relationship model will eventually be established after analyzing the characteristic changes in endogenous metabolites, the pharmacokinetic profile of ketamine and their metabolites, the addictive behavior, and biochemical parameters changes in vivo. With such model, the relationship between the characteristic metabolomics and the in vivo effect of ketamine can be explained. In addition, biomarkers related to drug use and addiction can also be found to clarity its mechanisms of toxicity/ addiction. The expected outcomes from the project will also provide experimental and theoretical basis for ketamine-related forensic practice, screening of effective drugs treating addiction withdrawal so as to find effective clinical therapy for drug addiction patients, and metabolomic study on other addictive substances.

氯胺酮滥用已成全球社会公害，通常检测氯胺酮方法只能反映短期用药情况，代谢组学则通过分析内源性小分子代谢物来揭示代谢组与机体病理生理变化相关性，为阐明其体内作用过程和致毒成瘾机制提供了新途径。基于我们前期发现给予氯胺酮大鼠体内代谢组发生改变，本课题以氯胺酮染毒未成瘾和成瘾大鼠为研究对象，采用核磁共振及色谱-质谱联用等技术进行氯胺酮的代谢组学研究，获取内源性代谢组数据，用模式识别方式和计算机分析寻找机体代谢特征，再结合毒性作用、成瘾行为表现、生化指标、氯胺酮原药及其代谢物的体内含量变化，建立"组-效"关联。解析代谢组特征信息与氯胺酮体内作用的关系，揭示氯胺酮引起机体的代谢特征，找到与氯胺酮中毒及成瘾相关的生物标记物，阐明其毒性作用和成瘾的分子机制，将为氯胺酮有关法医学实践、筛选和开发有效戒断药物及治愈成瘾患者提供新的实验基础和研究思路，也为其他成瘾物质的代谢组学研究奠定理论和实验基础。

项目背景: 氯胺酮滥用已成全球社会公害，目前对于氯胺酮的检测方法只能反映短期用药情况。代谢组学则通过分析内源性小分子代谢物来揭示代谢组与机体病理生理变化相关性，为阐明滥用物质体内作用过程和致毒、成瘾机制提供了新途径。.主要研究内容：在前期工作基础上优化氯胺酮成瘾模型和多种氯胺酮给药模型；进一步开发、建立了基于GC-MS，LC-MS的代谢组学分析平台, 利用NMR、GC-MS和LC-MS技术对模型大鼠体液、脑组织及氯胺酮的膀胱毒性等进行了代谢组学分析；除此之外，我们还对氯胺酮的神经保护作用进行了初步研究。.重要结果：（1）氯胺酮成瘾前后，大鼠尿液代谢组明显改变，其中差异最大的有1,3,7-三甲基尿酸、肌氨酸、甘氨酸、组胺、牛磺酸、2-氨基己二酸等代谢物，为潜在的尿液氯胺酮成瘾生物标记物；（2）氯胺酮成瘾大鼠的尿液代谢组具有性别差异；（3）长期氯胺酮给药可诱导的膀胱炎，膀胱炎模型大鼠尿液代谢组研究发现多种差异代谢物，主要参与亚油酸代谢，β-丙氨酸代谢和乙醛酸代谢途径；（4）氯胺酮重复给药可引起大鼠前额叶皮质、海马及纹状体的代谢组显著改变，其中嘌呤代谢，嘧啶代谢，丙氨酸-天冬氨酸-谷氨酸代谢，甘油磷脂代谢和精氨酸-脯氨酸代谢途径改变显著；（5）低剂量氯胺酮通过增加脑ATP的含量，降低TNF-α和IL-6等炎症因子，调控mTOR通路等途径改善颅脑损伤后大鼠的学习记忆功能，增强海马的神经可塑性。.科学意义：本项目为成瘾物质的体内过程研究、筛选和开发有效戒断药物及临床治疗成瘾患者及涉及氯胺酮等毒物（毒品）有关的法医学实践提供新的实验基础和研究思路，对揭示氯胺酮毒理学作用机制、阐明其耐受及成瘾行为发生、发展的影响因素具有重要的科学研究价值和社会意义。