中科院PLoS解析菌血症代谢组研究新发现

　　

近日，依托于中科院武汉物理与数学研究所的中国科学院生物磁共振分析重点实验室的生物医学代谢组学研究组，在菌血症的代谢组研究方面取得新进展，相关研究结果发表在PLoS ONE上。

菌血症（bacteremia）是指外界的细菌经由体表或感染的入口进入血液系统内繁殖并随血流在全身播散，从而激发炎症反应，导致全身炎症反应综合征（systemic inflammatory response syndrome, SIRS）和多系统器官功能障碍综合症（multiple organ dysfunction syndrome，MODS）。鉴定与菌血症有关的代谢产物并监视其动态变化有助于深入了解菌血症的发生和发展机制，同时也为对该病进行饮食干预提供了理论基础。

生物医学代谢组学组董方聪博士，采用基于NMR的代谢组学方法并结合多变量数据分析手段，研究了宿主对肺炎克雷伯菌感染的菌血症代谢应答。发现肺炎克雷伯菌感染的菌血症扰乱了机体的能量代谢，主要表现在促进了糖酵解、三羧酸循环，脂质的氧化和磷酸肌酸的分解；诱导了宿主的抗细菌内毒素，抗炎症和抗氧化反应。最后，菌血症也导致宿主肠道菌群的紊乱。研究结果还表明，额外的补充葡萄糖和富含高脂和高胆碱的食物摄入可以有效地缓解菌血症病人的病情。

原文摘要：

Metabolic Response to Klebsiella pneumoniae Infection in an Experimental Rat Model

Bacteremia, the presence of viable bacteria in the blood stream, is often associated with several clinical conditions. Bacteremia can lead to multiple organ failure if managed incorrectly, which makes providing suitable nutritional support vital for reducing bacteremia-associated mortality. In order to provide such information, we investigated the metabolic consequences of a Klebsiella pneumoniae (K. pneumoniae) infection in vivo by employing a combination of 1H nuclear magnetic resonance spectroscopy and multivariate data analysis. K. pneumoniae was intravenously infused in rats; urine and plasma samples were collected at different time intervals. We found that K. pneumoniae-induced bacteremia stimulated glycolysis and the tricarboxylic acid cycle and also promoted oxidation of fatty acids and creatine phosphate to facilitate the energy-demanding host response. In addition, K. pneumoniae bacteremia also induced anti-endotoxin, anti-inflammatory and anti-oxidization responses in the host. Furthermore, bacteremia could cause a disturbance in the gut microbiotal functions as suggested by alterations in a range of amines and bacteria-host co-metabolites. Our results suggest that supplementation with glucose and a high-fat and choline-rich diet could ameliorate the burdens associated with bacteremia. Our research provides underlying pathological processes of bacteremia and a better understanding of the clinical and biochemical manifestations of bacteremia.