Affiliation:
1. Department of Anatomy and Convergence Medical Sciences, College of Medicine, Institute of Medical Science, Tyrosine Peptide Multiuse Research Group, Anti-Aging Bio Cell Factory Regional Leading Research Center, Gyeongsang National University, 15 Jinju-daero 816 Beongil, Jinju 52727, Gyeongnam, Republic of Korea
Abstract
Glutamine (Gln), a non-essential amino acid, is synthesized de novo by glutamine synthetase (GS) in various organs. In the brain, GS is exclusively expressed in astrocytes under normal physiological conditions, producing Gln that takes part in glutamatergic neurotransmission through the glutamate (Glu)–Gln cycle. Because the Glu–Gln cycle and glutamatergic neurotransmission play a pivotal role in normal brain activity, maintaining Gln homeostasis in the brain is crucial. Recent findings indicated that a neuronal Gln deficiency in the medial prefrontal cortex in rodents led to depressive behaviors and mild cognitive impairment along with lower glutamatergic neurotransmission. In addition, exogenous Gln supplementation has been tested for its ability to overcome neuronal Gln deficiency and reverse abnormal behaviors induced by chronic immobilization stress (CIS). Although evidence is accumulating as to how Gln supplementation contributes to normalizing glutamatergic neurotransmission and the Glu–Gln cycle, there are few reviews on this. In this review, we summarize recent evidence demonstrating that Gln supplementation ameliorates CIS-induced deleterious changes, including an imbalance of the Glu–Gln cycle, suggesting that Gln homeostasis is important for emotional and cognitive functions. This is the first review of detailed mechanistic studies on the effects of Gln supplementation on emotional and cognitive functions.
Funder
National Research Foundation of Korea
Commercializations Promotion Agency for R&D Outcomes
Subject
Inorganic Chemistry,Organic Chemistry,Physical and Theoretical Chemistry,Computer Science Applications,Spectroscopy,Molecular Biology,General Medicine,Catalysis
Reference100 articles.
1. Roles of glutamine in neurotransmission;Albrecht;Neuron Glia Biol.,2010
2. Glutamine and glutamate: Nonessential or essential amino acids?;Watford;Anim. Nutr.,2015
3. Fernández-Montoya, J., Avendaño, C., and Negredo, P. (2017). The glutamatergic system in primary somatosensory neurons and its involvement in sensory input-dependent plasticity. Int. J. Mol. Sci., 19.
4. The biology and pathobiology of glutamatergic, cholinergic, and dopaminergic signaling in the aging brain;Gasiorowska;Front. Aging Neurosci.,2021
5. An energy budget for signaling in the grey matter of the brain;Attwell;J. Cereb. Blood Flow. Metab.,2001