基于GC-MS检测机械性窒息死大鼠脾组织代谢物时序性变化推断死亡时间  

Postmortem interval (PMI) estimation by time-dependent changes of metabolites of spleen in rats by GC-MS

作　　者：蔡山青 苏锐冰 汤畅 李嘉敏 吕俊耀 徐小虎 于晓军 Cai Shanqing;Su Ruibing;Tang Chang;Li Jiamin;Lv Junyao;Xu Xiaohu;Yu Xiaojunl(Medicolegal Department of Shantou University Medical College,Shantou G uangdong,515041;King-Med Diagnostics limited company of Changsha City of Hunan Province,Changsha 410000)

机构地区：[1]汕头大学医学院法医学教研室,广东汕头515041 [2]湖南长沙金域医学检验所有限公司,湖南长沙410000

出　　处：《中国法医学杂志》2018年第3期229-235,共7页Chinese Journal of Forensic Medicine

基　　金：国家自然科学基金项目(81072508);"十二五"国家科技支撑计划项目子课题(2012BAK02B02);汕头大学医学院创新强校工程.重大项目培育计划NSFC青年基金培育项目(923-38040227)

摘　　要：目的利用GC-MS检测窒息死SD-大鼠脾组织中代谢产物的时序性变化规律来推测其死亡时间(PMI)。方法密闭橡胶囊封闭大鼠口鼻致捂死,置于25℃、75%湿度的恒温恒湿箱中,分别于0h、24h、48h、72h、96h、120h 6个时间点提取脾组织,GC-MS检测各时间点脾脏组织中代谢物变化,逐步多元回归分析推断PMI方程。结果通过谱库定性分析,共检测出40种代谢物,构成了大鼠窒息死模型脾组织的"代谢物谱"。建立PLS-DA模型,通过VIP>1且Kruskal-Wallis检验(P<0.05)筛选出17种重要的代谢物,其中L-亮氨酸、L-脯氨酸、L-丙氨酸、L-赖氨酸、L-谷氨酸、亚油酸、L-色氨酸、磷酸等8种物质,简单线性回归方程R^2均大于0.69,多元逐步回归方程为Y_(PM)I=2.138+15.537X_(谷氨酸)+123.225X_(脯氨酸)(R^2=0.886,SE=14.56)。结论尸体脾组织代谢物呈时序性变化规律,与死亡时间存在明显线性关系,代谢组学理论和检测技术可作为PMI推断新方法,可进一步深入研究。Objective We performed a study to detect the correlations between the change of metabolites and the time of death in the spleen tissue of the asphyxiated SD rats with the technology of Gas chromatography-mass spectroscopy for the estimation of postmortem interval （PMI）. Methods A closed rubber balloon was used to seal the mouth and nose of rats to death, and then the rats were placed in awith a constant temperature of 25 C and humidity of 75% temperature and humidity chamber. The spleen tissues were extracted at 6 time points （Oh, 24h, 48h, 72h, 96h and 120h ） to detect the change of metabolites by GC-MS. PMI equation was inferred by stepwise multivariate regression analysis. Results We finally got 40 kinds of metabolitesby qualitative analysis of spectral library, which were the ＂metabolite spectrum＂ of the spleen tissue of the asphyxiated rat model. 17 kinds of important metabolites were screened by VIP 〉 1 in a PLS-DA model and P 〈 0. 05 in Kruskal-Wallis test, The top eight was L-leucine, L-proline, L-alanine, L-glutamic acid, linoleic acid, Octadecadienoic acid, L-tryptophan, and phosphoric acid , respectively and all their R2 was greater than 0. 69. The equation of multivariate stepwise regression was YPMI = 2. 138 ＋ 15. 537Xclu ＋ 123. 225Xpro （ R2 = 0. 886, SE = 14. 56 ）. Conclusion The metabolites of spleen tissue of cadaver have a regularity of time-dependent change and have obvious linear relationship with postmortem interval, which can be used as a new method of PMI estimation and further studied.

关 键 词：法医病理学 死亡时间 GC-MS 脾 窒息 

分 类 号：DF795.1[医药卫生—法医学]