This study determined the influence of γ-aminobutyric acid (GABA) on brain protein synthesis via the mammalian target of rapamycin (mTOR) pathway. Experiments were carried out on three groups of 6-wk-old male rats with 0%, 0.5%, and 1% GABA.
View Article and Find Full Text PDFThe purpose of this study was to determine whether the regulation of brain protein synthesis was mediated through changes in the plasma concentration of growth hormone (GH) when dietary γ-aminobutyric acid (GABA) treatment was manipulated in hypophysectomized or sham-operated aged rats. Experiments were done on four groups of hypophysectomized and sham-operated (24-wk-old) male rats given 0% or 0.5% GABA added to a 20% casein diet.
View Article and Find Full Text PDFJ Nutr Sci Vitaminol (Tokyo)
August 2011
We have shown that urinary urea excretion increased in rats given a lower quality protein. The purpose of present study was to determine whether the composition of dietary amino acids affects urea synthesis. Experiments were done on three groups of rats given diets containing a 10% gluten amino acid mix diet or 10% casein amino acid mix diet or 10% whole egg protein amino acids mix diet for 10 d.
View Article and Find Full Text PDFJ Nutr Sci Vitaminol (Tokyo)
April 2011
We have shown that the rate of brain protein synthesis in aged rats depended on the quality and quantity of dietary protein consumed. The purpose of this study was to determine whether the quality and quantity of dietary protein affected the phosphorylation of eukaryotic initiation factor (eIF) 4E-binding protein 1 (4E-BP1) and ribosomal protein S6 kinase (S6K1) and regulated the brain protein synthesis. Two experiments were done on three groups of 24-wk-old male rats given diets containing 20% casein, 20% gluten, or 20% gelatin (Experiment 1), and 20% casein, 5% casein or 0% casein (Experiment 2) for 10 d.
View Article and Find Full Text PDFThe mortality of individuals suffering from depression has been increasing, especially post-menopausal women; therefore, their care and treatment are important to maintain a high quality of life. In the present study, we evaluated the antidepressant-like effects of a major isoflavonoid, genistein (4',5,7-trihydroxyisoflavone), using a behavioral model of depression, the forced swimming test (FST), in ovariectomized rats. Daily administration of genistein to ovariectomized rats at a dosage of 10 mg/kg of body weight/d for 14 d significantly reduced the immobility time during the FST without changing motor dysfunction.
View Article and Find Full Text PDFWe have shown that urinary urea excretion decreased in rats fed a low gluten diet supplemented with dietary limiting amino acids. The purpose of present study was to determine whether the addition of dietary limiting amino acids to a low gluten diet affected the synthesis and degradation of N-acetylglutamate and regulated urea synthesis. Experiments were done on two groups of rats, given diets containing 10% gluten or 10% gluten+0.
View Article and Find Full Text PDFJ Nutr Sci Vitaminol (Tokyo)
February 2009
The purpose of this study was to determine whether gamma-aminobutyric acid (GABA) affects the rate of brain protein synthesis in ovariectomized female rats. Experiments were done on two groups of 24-wk-old ovariectomized female rats given 0 or 0.5% GABA added to the 20% casein diet.
View Article and Find Full Text PDFJ Nutr Sci Vitaminol (Tokyo)
February 2008
The purpose of this study was to determine whether the growth hormone (GH) affects the rate of brain protein synthesis in hypophysectomized aged rats. Experiments were conducted on three groups of 24-wk-old male rats: group 1 were hypophysectomized to reduce the level of plasma GH, group 2 were hypophysectomized and treated with GH and group 3 were sham-operated controls. The fractional rates of protein synthesis in the brains of hypophysectomized rats with GH were significantly greater than those in hypophysectomized rats without GH.
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