Urine Aging-related Proteome Analysis Of Healthy Humans

Background Urine is an easily available and non-invasive body fluid.Proteomics studies based on mass spectrometry have shown that urine contains thousands of proteins and is a potential source of biomarkers for various diseases.Aging is the pathological basis of many diseases.The changes of proteome in the elderly may reflect the physiological process of aging.Therefore,the study of age-related proteomics may help to understand the physiological changes related to aging and provide clues for the follow-up study of aging mechanism and markers.Methods 14 healthy men and 15 healthy women were enrolled and divided them into three groups according to their ages(20～30,40～50 and over 60 years old).250 ml urine was collected per person,the urine proteins were digested and then peptides were analyzed by label-free 2DLC/MS/MS approach,screening of age-related urinary protein.Meanwhile,we sought to provide insight into function of age-related proteins based on protein functional annotation.Results A total of 3008 proteins were identified in the urine of 29 healthy adults.In male group,there were 100 proteins differentially expressed in three groups,66 were over-expressed and 34 were under-expressed.In female group,there were 94 proteins differentially expressed in three groups,79 were overexpressed and 15 were under-expressed.There were 12 differential expressed proteins related to aging in both male and female groups.Protein function analysis showed that the up-regulated protein pathways in male group were mainly in protein homeostasis,vitamin metabolism and glucose metabolism,while the down regulated protein pathways were mainly in immune system and signal transduction pathway.The up-regulated protein pathways in female group were mainly concentrated in amino acid metabolism and vitamin metabolism.However,the down regulated protein pathways are mainly concentrated in the immune system.In general,the characteristics of protein related to aging including the involvement in the process of tissue remodeling,increased coagulation and fibrinolysis and immune disorders.Conclusions In this study,we compared the proteomic differences of urine in three different age groups of human.Proteins related to aging can be found in urine,which may be used as biomarkers of aging and providing basis for subsequent discovery of disease biomarkers.