Study on urine metabolomics of left-behind children with vitamin D deficiency under 1 year old in Zunyi area based on nuclear magnetic resonance / 中华实用儿科临床杂志

ABSTRACT

Objective To explore the characteristic changes in urinary metabolites in left-behind children with vitamin D deficiency under 1 year old in Zunyi area by metabolomic nuclear magnetic resonance (NMR) in order to provide new biomarkers for early diagnosis of vitamin D deficiency.Methods From January to August 2018,blood tests and urine collection were carried out on the left-behind children under 1 year old in Fenggang county,Bozhou district and Zheng'an county under Zunyi city by stratified sampling.Forty children diagnosed as a vitamin D deficiency were selected as a vitamin D deficiency group,and 40 children with normal urine test were selected as a healthy control group.For urine sampling,SIMCA-P + software was applied to analyze the integral value of hydrogen spectrogram by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) was used to distinguish the difference in urine metabolites between two groups of the left-behind children.Orthogonal partial least squares discriminant analysis (OPLS-DA) was used to screen different metabolites.Results The serum level of 25-hydroxy vitamin D [25-(OH) D] [(32.0 ± 3.6) nmol/L] in the healthy control group was higher than that in the vitamin D deficiency group [(15.8±2.3) nmol/L],and the difference was statistically significant (P ＜ 0.05).PCA and PLS-DA analysis showed significant differences in urine metabolites between the healthy control group and the vitamin D deficiency group (P ＜ 0.05).OPLS-DA indicated R2X =0.365,Q2 =0.978,which further verified the difference of metabolites.Compared with the healthy control group,the urine of methyl malonic acid,3-hydroxy butyrate,N-acetyl glycoprotein signal,glutamic acid,dimethyl glycine,2-ketone glutaric acid,taurine,fumaric acid salt level increased significantly in the vitamin D deficiency group,and the differences were statistically significant (| r| ＞ 0.602,all P ＜ 0.05,df =39).However,the levels of ethyl malonic acid,creatine,choline,glycerophosphalocholine and equine were significantly decreased,and the differences were statistically significant (| r | ＞ 0.602,all P ＜ 0.05,df =39).Conclusions The left-behind children under 1 year old with vitamin D deficiency in Zunyi region are mainly characterized by disorder in energy metabolism,lipid metabolism,amino acid metabohsm and intestinal microbial metabolism disorders,and their differential metabolites have potential application value in early diagnosis and pathogenesis of vitamin D deficiency.