Dietary animal proteins alter monoamine metabolism in the brain.
Several amino acids have effects on mental function, including sedative, antidepressant-like and anxiolytic-like effects. However, the influence of integrated amino acid nutrition as protein constituents on mental function remains unclear. Therefore, the purpose of the present study was to compare the influence of chicken, pork and beef protein extracts on brain monoamine metabolism in mice. Changes in monoamine levels and their turnover rates in the brain were induced by different protein sources. In particular, chicken protein group showed the highest norepinephrine levels in the hippocampus and hypothalamus, and beef protein extract caused an activation of the serotonergic system in the hypothalamus, although there were no significant differences in amino acid compositions of these protein extracts. Therefore, it was revealed that amino acid compositions in dietary protein did not induce alteration in monoamine metabolism. However, there were differences in small molecular peptides, such as creatine, carnosine and anserine levels in animal protein extracts. In conclusion, monoamine metabolism was altered by dietary protein sources. However, it was indicated that the alteration in monoamine metabolism may be independent from amino acid compositions in dietary protein. In addition, alteration in monoamine metabolism depending on the dietary protein sources may be induced by small molecular peptides.
Laboratory of Regulation in Metabolism and Behavior, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Higashi, Fukuoka, Japan.
Mao
M
Nagasawa
Tatsuro
T
Murakami
Mikako
M
Sato
Yoshihisa
Y
Takahata
Fumiki
F
Morimatsu
Mitsuhiro
M
Furuse
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D002417:Cattle; D002645:Chickens; D004044:Dietary Proteins / Q000032:analysis / Q000494:pharmacology*; D008297:Male; D008460:Meat; D051379:Mice; D008813:Mice, Inbred ICR; D008970:Molecular Weight; D010455:Peptides / Q000032:analysis; D013552:Swine
D000596:Amino Acids; D015306:Biogenic Monoamines; D004044:Dietary Proteins; D010455:Peptides