The Pilot Study For The Characteristics Of Urine Amino Acids Metabolism In Neurodegenerative Disease

Chapter 1 The Pilot study for the biomarkers of amnestic mild cognitive impairmentObjective:MCI is increasingly recognized to be the prodromal stage of AD.The purpose of this study was to explore a noninvasive biomarker that can assist in diagnosis of aMCI.Methods:Urinary differentially metabolized amino acids were detected by targeted approach from 98 aMCI patients and 110 healthy elders.Then,we validated from 26 healthy controls and 26 aMCI patients who were recruited from the memory clinic and evaluate the value in diagnosis of aMCI.Results:We discovered that arginine and cysteine are different in a community cohort study and validated that one of them,arginine,was significantly lower in aMCI(p=0.019,q=0.097).Additionally,we found aMCI patients had significantly reduced GABR with a decrease in both arginine and ornithine concentrations(p=0.013,q=0.027).When GABR is 0.523,the sensitivity and specificity reaches the maximal value(AUC=0.797).Conclusion:aMCI patients have dysregulated arginine metabolism,and urine GABR may be a potentially useful diagnostic biomarker for aMCI in older adults.Chapter 2 The Pilot study for the the characteristic of urine amino acids metabolism in Parkinson's disease.Objective:Previous studies found that Amino acids metabolism are dysregulated in Parkinson's disease(PD),which may play an essential role in pathogenesis of PD.The purpose of this study was to analyze the characteristic of urine amino acids metabolism in PD.Methods:Urinary differentially metabolized amino acids were detected by targeted approach from 54 PD patients and 54 healthy controls.Result:We discovered that the level of methionine(p=0.0025)and tyrosine(p<0.001)in PD was significantly higher than control while arginine was lower(p<0.001).The level of methionine and arginine were significantly associated with UPDRS score and H-Y stage(p<0.05).Conclusion:PD patients have dysregulated arginine,methionine and tyrosine metabolism.The level of methionine and arginine may have a correlaction with the severity of motor symptoms.