Glutamine and Glutamate Complex, as Measured by Functional Magnetic Resonance Spectroscopy, Alters During Face-Name Association Task in Patients with Mild Cognitive Impairment and Alzheimer’s Disease

Article type: Research Article

Authors: Jahng, Geon-Ho^{a; *} | Oh, Janghoon^b | Lee, Do-Wan^c | Kim, Hyug-Gi^b | Rhee, Hak Young^d | Shin, Wonchul^d | Paik, Jong-Woo^e | Lee, Kyung Mi^f | Park, Soonchan^a | Choe, Bo-Young^c | Ryu, Chang-Woo^a

Affiliations: [a] Department of Radiology, Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, Gangdong-gu, Seoul, Republic of Korea | [b] Department of Biomedical Engineering, Graduate School, Kyung Hee University, Giheung-gu, Yongin-si, Gyeonggi-do, Republic of Korea | [c] Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seocho-Gu, Seoul, Republic of Korea | [d] Department of Neurology, Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, Gangdong-gu, Seoul, Republic of Korea | [e] Department of Mental Health, Kyung Hee University Hospital, College of Medicine, Kyung Hee University, Dongdaemun-gu, Seoul, Republic of Korea | [f] Department of Radiology, Kyung Hee University Hospital, College of Medicine, Kyung Hee University, Dongdaemun-gu, Seoul, Republic of Korea

Correspondence: [*] Correspondence to: Geon-Ho Jahng, PhD, Professor of Radiology, Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, #892 Dongnam-ro, Gangdong-Gu, Seoul 134-727, Republic of Korea. Tel.: +82 2 440 6187; Fax: +82 2 440 6932; E-mail: ghjahng@gmail.com.

Abstract: Background: The metabolite response during a memory task in Alzheimer’s disease (AD) patients is unknown. Objective: To investigate the metabolite changes in subjects with AD, amnestic mild cognitive impairment (aMCI), and cognitively normal (CN) elderly during a memory task using functional magnetic resonance spectroscopy (fMRS). Methods: This study involved 23 young normal controls (YC), 24 CN elderly, 24 aMCI, and 24 mild and probable AD individuals. fMRS data were acquired at the precuneus and posterior cingulate brain regions during a face-name association task. Statistical analyses of quantified metabolites were performed to evaluate differences of the metabolite values between the stimulation conditions and among the four subject groups. Receiver operating curve analysis was performed to evaluate whether the metabolic changes after functional activations can differentiate the subject groups. Result: Glutamine and glutamate complex (Glx) was statistically significantly different between the fixation and repeat conditions in aMCI (p = 0.0492) as well as between the fixation and the novel conditions in the AD (p = 0.0412) group. The total N-acetylaspartate (tNAA) was statistically significantly different among the four subject groups in the fixation condition (DF = 3, F = 7.673, p <  0.001), the novel condition (DF = 3, F = 6.945, p <  0.001), and the repeat condition (DF = 3, F = 7.127, p <  0.001). tNAA, tCr, and mIns could be used to differentiate CN from aMCI. Furthermore, tNAA, tCr, Glx, and Glu could also differentiate CN from AD, and aMCI from AD. Conclusion: Glx was altered during a stimulation that may be used to evaluate neuronal dysfunction in a demented patient. tNAA and tCr were reduced in patients with AD.

Keywords: Alzheimer–s disease, functional magnetic resonance spectroscopy, glutamine and glutamate complex (Glx), mild cognitive impairment, total N-acetylaspartate (tNAA)

DOI: 10.3233/JAD-150877

Journal: Journal of Alzheimer's Disease, vol. 52, no. 1, pp. 145-159, 2016