title: Plasma Angiotensin-(1-7) is a Potential Biomarker for Alzheimer's Disease.
abstract: Brain angiotensin-(1-7) (Ang-(1-7)) concentration has been shown to be reduced and inversely correlated with tau pathology in a mouse model of Alzheimer's disease (AD). In this study, to determine whether the concentration of Ang-(1-7) and the activity of its converting enzyme angiotensin-converting enzyme 2 were altered in plasma under AD context, the plasma samples from 110 AD patients and 128 age- and gender-matched controls were screened. In AD patients, the plasma concentration of Ang-(1-7) was significantly reduced (15.63±4.35pg/mL vs. 19.58±3.22pg/mL, P<0.001) and positively correlated with cognitive functions (R=0.66, P<0.001). Meanwhile, receiver-operating characteristic analysis showed that the Ang-(1-7) concentration in plasma could distinguish AD patients from controls with the sensitivity and specificity of 69.1% and 74.2%, respectively, when the optimal cut-off value (18.2 pg/mL) was chosen. These findings indicate that plasma Ang-(1-7) may represent a potential biomarker for AD diagnosis, and further suggest an involvement of this heptapeptide in the pathogenesis of this disease.
authors.affiliation: Department of Neurology, Nanjing First Hospital, Nanjing Medical University, No.68, Changle Road, Nanjing, China. jt870918@163.com.
authors.forename: Teng
authors.initials: T
authors.lastname: Jiang
authors.forename: Lan
authors.initials: L
authors.lastname: Tan
authors.forename: Qing
authors.initials: Q
authors.lastname: Gao
authors.forename: Huan
authors.initials: H
authors.lastname: Lu
authors.forename: Xi-Chen
authors.initials: XC
authors.lastname: Zhu
authors.forename: Jun-Shan
authors.initials: JS
authors.lastname: Zhou
authors.forename: Ying-Dong
authors.initials: YD
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood* / Q000150:complications; D000803:Angiotensin I / Q000097:blood*; D000085962:Angiotensin-Converting Enzyme 2; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010446:Peptide Fragments / Q000097:blood*; D007703:Peptidyl-Dipeptidase A / Q000097:blood; D011569:Psychiatric Status Rating Scales; D012680:Sensitivity and Specificity; D013223:Statistics as Topic
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D000803:Angiotensin I; D007703:Peptidyl-Dipeptidase A; C000705307:ACE2 protein, human; C000705328:Ace2 protein, mouse; D000085962:Angiotensin-Converting Enzyme 2; C118790:angiotensin I (1-7)