Open AccessAcute effect of glucose on cerebral blood flow, blood oxygenation, and oxidative metabolism
Author(s) -
Xu Feng,
Liu Peiying,
Pascual Juan M,
Xiao Guanghua,
Huang Hao,
Lu Hanzhang
Publication year - 2015
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.22658
Subject(s) - postprandial , cerebral blood flow , ingestion , medicine , endocrinology , carbohydrate metabolism , metabolism , chemistry , oxidative phosphorylation , blood flow , citric acid cycle , insulin , biology , biochemistry
While it is known that specific nuclei of the brain, for example hypothalamus, contain glucose‐sensing neurons thus their activity is affected by blood glucose level, the effect of glucose modulation on whole‐brain metabolism is not completely understood. Several recent reports have elucidated the long‐term impact of caloric restriction on the brain, showing that animals under caloric restriction had enhanced rate of tricarboxylic acid cycle (TCA) cycle flux accompanied by extended life span. However, acute effect of postprandial blood glucose increase has not been addressed in detail, partly due to a scarcity and complexity of measurement techniques. In this study, using a recently developed noninvasive MR technique, we measured dynamic changes in global cerebral metabolic rate of O 2 (CMRO 2 ) following a 50 g glucose ingestion ( N = 10). A time dependent decrease in CMRO 2 was observed, which was accompanied by a reduction in oxygen extraction fraction (OEF) with unaltered cerebral blood flow (CBF). At 40 min post‐ingestion, the amount of CMRO 2 reduction was 7.8 ± 1.6%. A control study without glucose ingestion was performed ( N = 10), which revealed no changes in CMRO 2 , CBF, or OEF, suggesting that the observations in the glucose study was not due to subject drowsiness or fatigue after staying inside the scanner. These findings suggest that ingestion of glucose may alter the rate of cerebral metabolism of oxygen in an acute setting. Hum Brain Mapp 36:707–716, 2015 . © 2014 Wiley Periodicals, Inc .