[Comparison of differential metabolites in urine of the middle school students with chronic fatigue syndrome before and after exercise].

To study the differential metabolites in urine and the characteristics of metabolic pathway of middle school students with chronic fatigue syndrome (CFS) before and after exercise, and then explain the metabolic mechanism of CFS.Eight male middle school students (age:17-19) with CFS were selectedas the CFS group according to CFS screening criteria of the U.S. centers.At the same time, 8 male health students of the same age from the same school were selected as the control group. They were administrated to do one-time exercise on the improved Harvard step (up and down steps 30 times/min for 3minutes). Their urinewascollected before and after exercise, and the differential metabolitesin urine were detected by liquid chromatography-mass spectrometry (LC-MS). The multidimensional statistical methods were used to analyze the metabolites by principal component analysis (PCA) and orthogonal projections to latent structures-discriminant analysis (OPLS-DA). Finally, MetPA database was used to analyze the metabolites and to construct the correlativemetabolic pathways.

Compared with the control group, the creatine, indoleacetaldehyde, phytosphingosine and pyroglutamic acid were selected as differential metabolites and the contents of those were decreased significantly (P<0.05 or P<0.01) in CFS groupbefore the step movement. However, 11 differential metabolitesin CFS group were selected out after exercise, which were nonanedioic acid, methyladenosine, acetylcarnitine, capric acid, corticosterone, creatine, levonorgestrel, pantothenic acid, pyroglutamic acid, xanthosine and xanthurenic acid in sequence, the contents of methyladenosine and creatinewere significantly increased (P<0.05) and the contents of the other 9 differentialmetabolites were significantly decreased (P<0.05 or P<0.01)compared with the control group.The 15 differential metabolites mentioned above were input MetPA database in order to analyze the metabolic pathways weighted score.The results showed that the arginine-proline metabolism pathway disordersweredetected in theCFS group before exercise, the marker metabolite wascreatine. And 3 metabolic pathwaysdisorder weredetectedin the CFS groupafter exercise, which were arginine-proline metabolism, biosynthesis of pantothenic acid and CoA, steroid hormone biosynthesis, and the marker metabolites, in turn, werecreatine, pantothenic acid and corticosterone.

The disorder of arginine-proline metabolic pathway is detected in CFS middle school students before exercise intervention. After exercise, it can be detected that the steroid hormone biosynthetic metabolic pathway, pantothenic acid and CoA metabolic pathways also have metabolic disorders.