大鼠气管内注入纳米二氧化钛后的血浆代谢组学研究

目的 运用一维磁共振氢谱(1H MR)结合模式识别的代谢组学技术探讨大鼠气管内注入纳米二氧化钛(nano-TiO2)的毒效应,并寻找毒效应的靶器官及生物标志物.方法 将24只SD大鼠按数字表法随机分为4组,分别为高剂量组(40.0 mg/kg nano-TiO2)、中剂量组(4.0 mg/kg nano-riO2)、低剂量组(0.4 mg/kg nano-TiO2)和对照组(生理盐水),每组各6只大鼠.按0.1 ml/100 g采用非暴露式气管内注入方式,染毒1次.观察1周后,进行血浆1H MR检测,并对代谢图谱进行主成分分析(PCA).同时摘取心、肺、肝、肾等器官作组织病理学检查.结果 血浆代谢组学分析表明:高剂量组乳酸相对含量(37.86±2.58)×10-3]、柠檬酸相对含量(2.21±0.45)×10-3]、胆碱相对含量(7.74±0.76)×10-3]和肌酸相对含量(4.17 d-1.15)×10-3]低于对照组(52.07±5.12)×10-3、(3.01±0.21)×10-3、(9.28±0.78)×10-3、(8.59±2.64)×10-3](t值分别为-6.024、-3.177、-3.374、-4.215,P值均<0.05);而葡萄糖相对含量(19.41±1.72)×10-3]高于对照组(14.45±2.45)×10-3](t=2.802,P<0.05);中剂量组乳酸相对含量(44.39±5.09)×10-3]和肌酸相对含量(3.67±0.76)×10-3]低于对照组(52.07±5.12)×10-3、(8.59±2.64)×10-3](t值分别为-3.254、-4.694,P值均<0.05);低剂量组丙酮酸相对含量(3.84±0.70)×10-3]高于对照组(3.13×±0.46)×10-3](t=2.787,P<0.05),胆碱相对含量(8.10±0.72)×10-3]低于对照组(9.28±0.78)×10-3](t=-2.602,P<0.05).各剂最组大鼠各个组织脏器均未见明显的病理变化.结论 大鼠肺脏、肝脏、肾脏和心脏是nano-TiO2气管注入染毒的靶器官;乳酸、丙酮酸、匍萄糖、柠檬酸、胆碱和肌酸可作为寻找nano-TiO2致机体毒作用靶器官的参考生物标志物.

Metabonomic study of plasma after intratracheully instilling titanium dioxide nanoparticles in rats

Objective 1H magnetic resonance (1H MR) speetroseopic technique in combination with pattern recognition technique were applied to analyze toxic effects of rats which were intratracheally instilled with titanium dioxide nanoparticles (nano-TiO2) as well as to detect the target organs and biomarkers associated with the toxic effects. Methods Twenty-four SD male rats were divided into 4 groups randomly which were high dose group(40 mg/kg nano-TiO2), moderate dose group(4 mg/kg nano-TiO2), low dose group(0.4 mg/kg nano-TiO2) and control group (0.9% NaC1 solution) respectively,there were six rats per group. All rats were exposed to the object by single intratracheally instilling at a volume of 0.1 ml/ 100 g. After one week observation, 1H MR spectra of plasma were measured and analyzed by principal component analysis. Histopathologic examination for tissues such as heart, lung, liver, and kidney were performed simultaneously. Results The relative content of lactace (37.86±2.58)×10-3], citrate (2.21±0.45)×10-3],choline(7.74±0.76)×10-3] and creatine (4.17±1.15)×10-3] in high dose group were significantly decreased as compared with those(52.07±5.12)×10-3, (3.01±0.21)×10-3, (9.28±0.78)×10-3, (8.59±2.64)×10-3] in control group (t values were-6.024,-3.177, -3.374,-4.215 respectively, P<0.05), however the relative content of glucose (19.41±1.72)×10-3] was significantly increased compared with that (14.45±2.45)×10-3] in control group (t value was 2. 802,P<0.05). The relative content of lactace(44.39±5.09)×10-3] land creatine (3.67±0.76)×10-3] in moderate group was significantly decreased compared with those (52.07±5.12)×10-3, (8.59±2.64)×10-3] in control group (t values were-3.254,-4.694 respectively, P<0.05). The relative content of pyruvate(3.84±0.70)×10-3]was significantly increased in low dose group as compared with that (3.13±0.46)×10-3] in control group (t value was 2.787, P<0.05), however the relative content of creatine (8.10±0.72)×10-3] was significantly decreased compared with that (9.28±0.78)×10-3] in control group (t value was -2.602, P<0.05). No significant difference was found between other experimental groups and control group. No visible damage was found in histopathologic examination. Conclusion Lung, liver, kidney and heart were the target organs of rats which were intratracheally instilling titanium dioxide nanoparticles. Lactate, pyruvate, glucose, citrate, choline and creatine can be presumed as the biomarkers when searching the target organs of the toxic effects.