Gut microbiota of mice putatively modifies amino acid metabolism in the host brain. Issue 6 (10th April 2017)

• Record Type: Journal Article
• Authors: Kawase, Takahiro; Nagasawa, Mao; Ikeda, Hiromi; Yasuo, Shinobu; Koga, Yasuhiro; Furuse, Mitsuhiro
• Is Part Of: British journal of nutrition. Volume 117:Issue 6(2017)
• Page Start: 775
• Page End: 783
• Publication Date: 2017-04-10
• Subjects: Gut microbiota, -- Germ-free mice, -- D-Amino acids, -- L-Amino acids, -- Brain, -- Ageing; Nutrition -- Periodicals; 572.4
• DOI: 10.1017/S0007114517000678
• Languages: English
• ISSNs: 0007-1145

Abstract

Abstract: Recently, it has been found that the gut microbiota influences functions of the host brain by affecting monoamine metabolism. The present study focused on the relationship between the gut microbiota and the brain amino acids. Specific pathogen-free (SPF) and germ-free (GF) mice were used as experimental models. Plasma and brain regions were sampled from mice at 7 and 16 weeks of age, and analysed for freed - andl -amino acids, which are believed to affect many physiological functions. At 7 weeks of age, plasma concentrations ofd -aspartic acid (d -Asp), l -alanine (l -Ala), l -glutamine (l -Gln) and taurine were higher in SPF mice than in GF mice, but no differences were found at 16 weeks of age. Similar patterns were observed for the concentrations ofl -Asp in striatum, cerebral cortex and hippocampus, andl -arginine (l -Arg), l -Ala andl -valine (l -Val) in striatum. In addition, the concentrations ofl -Asp, d -Ala, l -histidine, l -isoleucine (l -Ile), l -leucine (l -Leu), l -phenylalanine andl -Val were significantly higher in plasma of SPF mice when compared with those of GF mice. The concentrations ofl -Arg, l -Gln, l -Ile andl -Leu were significantly higher in SPF than in GF mice, but those ofd -Asp, d -serine andl -serine were higher in some brain regions of GF mice than in those of SPF mice. In conclusion, the concentration of amino acids in the host brain seems to be dependent on presence of the gut microbiota. Amino acid metabolism in the host brain may be modified by manipulating microbiota communities.