Metabonomics Study Of Blood And Urine In Patients With Calcium Kidney Stones

Objectives Metabolomics method is used to study the pathogenesis of calcium-containing kidney stones and find potential molecular markers for blood and urine metabolism.Methods Between May 2016 and February 2017,we collected blood and urine specimens from 24 patients with kidney stones and 30 healthy controls.Supernatant is collected after centrifugation within 30 minutes and stored in liquid nitrogen.Samples were examined using ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry(UPLC-LTQ/Orbitrap MS).Principal Component Analysis(PCA)and Partial Least Squares-Discriminant Analysis(PLS-DA)methods for pattern recognition.Find differential metabolites by the importance of predictors(VIP values)and correlation coefficients(P values).The Kyoto Biogen and Genome Encyclopedia(KEGG)database was used to identify the metabolic pathways involved in potential biomarkers.Results There was no significant difference in age,sex ratio and BMI between the two groups.Thirteen cases of stone samples obtained from 24 patients with stones,including 5 pure calcium oxalate stones(38.5%),6 mixed stones(46.2%)containing calcium oxalate as the main component,and 2 mixed stones(15.4%)containing carbonate apatite as the main component.Twenty patients underwent 24-hour urinalysis,including 2 cases of hypercalciuria(10%),20 cases of hyperoxaluria(100%),14 cases of hypoxicuria(70%),2 cases(10%)of hypernatremia and 8 cases(40%)of low urine output.Compared with the normal control group,uric acid,choline,carnitine,creatine,3-hydroxydodecanoic acid,methionine,hypoxanthine,perillyl alcohol,3-propyl acrolein,4-aminobutyraldehyde,3-buten-1-amine,phenylalanine,proline,tyrosine,valine,tryptophan and butanone metabolites were up-regulated in patients with kidney stones,anddodecanedioic acid,aconitic acid,7-oxo-11 E,13-tetradecadienoic acid,citric acid,2,5-furandicarboxylic acid,3-furoic acid,3-oxoglutaric acid,trans-aconitate,aminoacetone,sphinganine,caproaldehyde and C16 sphingosine metabolites were down-regulated.In urea,3-aminopropanal,urea,creatinine and choline metabolites were up-regulated,salicylic acid,decanoyl-L-carnitine,3-hydroxyhippuric acid,succinic acid,delta-guanidinovaleric acid,itaconic acid,salicylic acid,n-Acetyl-DL-tryptophan,glutaric acid,hippuric acid,N-acetylcadaverine,adipic acid,N-acetyl-L-aspartate,p-tolyl Sulfate,aspartyl-proline,uracil,polyethylene-oxidized,oxoglutaric acid,hydroxyprolyl-histidine,aconitic acid,citric acid,threonic acid,tiglic acid,aminohippuric acid,3-hydroxy-L-proline,histidine,2-piperidinone,N-isovalerylglycine,acetyl-DL-leucine,tyrosine,indoleacrylic acid,N-Formyl-L-glutamate,1-methyladenosine,N-Alpha-acetyllysine,tryptophan,butyryl-L-carnitine,aspartyl-Leucine and piperidine metabolites were down-regulated.The metabolites with simultaneous changes in blood and urine are aconitic acid,citric acid and choline,and metabolites with reversed changes are tyrosine and tryptophan.The above differential metabolites are mainly involved in arginine and valine metabolism,phenylalanine,tyrosine and tryptophan metabolism,histidine metabolism,TCA cycle,sphingolipid metabolism,energy metabolism and purine metabolism.Conclusions The formation of calcium-containing kidney stones involves multiple metabolic pathways.Small molecules of hematuria metabolism are expected to be markers for the diagnosis of calcium-containing kidney stones.