著者
Yukina YAMAMOTO YUMEN Shunsuke MORITA Mayu YOSHIKAWA Hirofumi SONOKI Hiroshi IWAMOTO Yasuhiro TAKEDA Aki OGAWA Yukiko KOBAYASHI Masashi KUWAHATA Yasuhiro KIDO
出版者
Center for Academic Publications Japan
雑誌
Journal of Nutritional Science and Vitaminology (ISSN:03014800)
巻号頁・発行日
vol.68, no.5, pp.383-389, 2022-10-31 (Released:2022-10-31)
参考文献数
20

The indicator amino acid oxidation method is a relatively new method for determining protein requirements. Our hypothesis was that the protein requirement of the casein-whey protein mixture (70% casein and 30% whey protein) was lower than the protein requirement of plain casein, because casein and whey proteins compensate for the lack of the first-limiting amino acids. The optimal mixing ratio was determined based on the amino acid scoring pattern which is used to calculate the digestible indispensable amino acid score. In this study, digestibility was not considered to determine the optimal mixing ratio because dairy protein is a good source of digestible protein. This study aimed to evaluate the protein requirements of Japanese young men by consuming casein and casein-whey protein mixture. Ten healthy young men (22±0.2 y old) participated in 12 experiments according to a graded protein intake (0.5, 0.7, 0.9, 1.0, 1.2, 1.4 g/kg/d) of casein and casein-whey protein mixture. The mean protein requirement was calculated as the breakpoint of breath 13CO2 enrichment using change-point regression models. The mean protein requirements of Japanese young men by consuming casein and casein-whey protein mixture were estimated to be 1.00 g/kg/d and 0.90 g/kg/d, respectively. These estimated requirements were consistent with the protein quality expected from the amount of the first-limiting amino acids. The indicator amino acid oxidation method may be useful to evaluate protein quality.
著者
Hiroki Sugiyama Yukiko Kobayashi Yoshio Sumida Sayori Wada Michiyo Tani Yoshiaki Shizukawa Koji Shirota Yukiko Sasai Taro Suzuki Wataru Aoi Yuji Naito Masashi Kuwahata
出版者
SOCIETY FOR FREE RADICAL RESEARCH JAPAN
雑誌
Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)
巻号頁・発行日
vol.70, no.1, pp.46-53, 2022 (Released:2022-01-01)
参考文献数
32
被引用文献数
2

The aim of this study was to investigate whether a nutritional intervention motivating increased vegetable consumption would be an effective treatment and diet therapy for patients with non-alcoholic fatty liver disease. We examined 15 patients with this disease (5 men and 10 women). During the 6-month intervention period, all participants received a small amount of vegetables twice a month as a nutritional education tool aimed at increasing vegetable consumption. They also received nutritional counseling and underwent ultrasound and blood biochemical examinations at baseline and 3 and 6 months after initiation of the intervention. Moreover, they were requested to submit dietary records for any 2 days. Green, white, and total vegetable intakes were significantly higher at 3 and 6 months than at baseline in 8 patients. These patients had significantly lower alanine amino­transferase and triglyceride concentrations than those whose vegetable intake did not increase. Additionally, green vegetable intake significantly negatively correlated with weight at 3 and 6 months (r = −0.617, p = 0.032 and r = −0.848, p = 0.008, respectively). These results suggest that our nutritional approach effectively increased vegetable consumption in at least some patients with non-alcoholic fatty liver disease, consequently improving their condition.
著者
Yukimi Yano Chihiro Maeda Ichiro Kaneko Yukiko Kobayashi Wataru Aoi Masashi Kuwahata
出版者
SOCIETY FOR FREE RADICAL RESEARCH JAPAN
雑誌
Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)
巻号頁・発行日
vol.69, no.2, pp.122-130, 2021 (Released:2021-09-01)
参考文献数
37
被引用文献数
1

We recently reported that dietary cystine maintained plasma mercaptalbumin levels in rats fed low-protein diets. The present study aimed to compare the influence of low-protein diets supplemented with cystine and methionine, which is another sulfur amino acid, on plasma mercaptalbumin levels in rats. Male Sprague–Dawley rats were fed a 20% soy protein isolate diet (control group), 5% soy protein isolate diet (low-protein group) or 5% soy protein isolate diet supplemented with either methionine (low-protein + Met group) or cystine (low-protein + Cyss group) for 1 week. The percentage of mercaptalbumin within total plasma albumin of the low-protein + Met group was significantly lower than that of the control and low-protein + Cyss groups. No significant differences in the mRNA levels of tumor necrosis factor-α, interleukin-6, interleukin-1β, and cyclooxygenase 2 in blood cells were observed between the low-protein + Met and low-protein + Cyss groups. Treatment with buthionine-(S,R)-sulfoximine, an inhibitor of glutathione synthesis, did not influence the percentage of mercaptalbumin within total plasma albumin in rats fed the low-protein diet supplemented with cystine. These results suggest that supplementation with cystine may be more effective than that with methionine to maintain plasma mercaptalbumin levels in rats with protein malnutrition. Cystine might regulate plasma mercaptalbumin levels via the glutathione-independent pathway.
著者
Akane Miki Yoshitaka Hashimoto Muhei Tanaka Yukiko Kobayashi Sayori Wada Masashi Kuwahata Yasuhiro Kido Masahiro Yamazaki Michiaki Fukui
出版者
日本酸化ストレス学会
雑誌
Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)
巻号頁・発行日
vol.61, no.1, pp.74-77, 2017 (Released:2017-07-01)
参考文献数
31
被引用文献数
15

Dietary acid load is important information, however, survey of food intake needs time and skill. Therefore, it is difficult to survey food intake from all patients. It remains to be elucidated the association between dietary acid load and urinary pH in patients with type 2 diabetes. In this cross-sectional study of 173 patients, we investigated the relationship between urinary pH and dietary acid load, assessed with potential renal acid load. Habitual food and nutrient intake was assessed by a self-administered diet history questionnaire. Urinary pH was negatively correlated with potential renal acid load (r = –0.24, p = 0.002). Multivariate regression analysis revealed that potential renal acid load (standardized regression coefficient = –0.21, p = 0.036) was associated with urinary pH after adjusting for covariates. In addition, according to the receiver operator characteristic analysis, the optimal cut-off point of urinary pH for high dietary acid load, defined as potential renal acid load over 7.0 mEq/day was 5.7 (area under the receiver operator characteristic curve 0.63 (95% CI 0.54–0.71), sensitivity = 0.56, specificity = 0.70, p = 0.004). Urinary pH was associated with dietary acid load in patients with type 2 diabetes. We suggest that urinary pH can be a practical screening marker for dietary acid load in patients with type 2 diabetes.