著者

Rie Hashimoto Atsuko Sakai Masumi Murayama Arisa Ochi Tomoki Abe Katsuya Hirasaka Ayako Ohno Shigetada Teshima-Kondo Hiroaki Yanagawa Natsuo Yasui Mikiko Inatsugi Daisuke Doi Masanori Takeda Rie Mukai Junji Terao Takeshi Nikawa

出版者

The University of Tokushima Faculty of Medicine

雑誌

The Journal of Medical Investigation (ISSN:13431420)

巻号頁・発行日

vol.62, no.3.4, pp.177-183, 2015 (Released:2015-09-18)

参考文献数

20

被引用文献数

9 22

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Background: In recent years, the number of bedridden people is rapidly increasing due to aging or lack of exercise in Japan. This problem is becoming more serious, since there is no countermeasure against it. In the present study, we designed to investigate whether dietary proteins, especially soy, had beneficial effects on skeletal muscle in 59 volunteers with various physical activities. Methods: We subjected 59 volunteers with various physical activities to meal intervention examination. Persons with low and high physical activities were divided into two dietary groups, the casein diet group and the soy diet group. They ate daily meals supplemented with 7.8 g of powdered casein or soy protein isolate every day for 30 days. Bedridden patients in hospitals were further divided into three dietary groups: the no supplementation diet group, the casein diet group and the soy diet group. They were also subjected to a blood test, a urinalysis, magnetic resonance imaging analysis and muscle strength test of the knee before and after the meal intervention study. Results: Thirty-day soy protein supplementation significantly increased skeletal muscle volume in participants with low physical activity, compared with 30-day casein protein supplementation. Both casein and soy protein supplementation increased the volume of quadriceps femoris muscle in bedridden patients. Consistently, soy protein significantly increased their extension power of the knee, compared with casein protein. Although casein protein increased skeletal muscle volume more than soy protein in bedridden patients, their muscle strength changes by soy protein supplementation were bigger than those by casein protein supplementation. Conclusions: The supplementation of soy protein would be one of the effective foods which prevent the skeletal muscle atrophy caused by immobilization or unloading. J. Med. Invest. 62: 177-183, August, 2015

著者

Katsuya HIRASAKA Shinobu SAITO Saki YAMAGUCHI Riho MIYAZAKI Yao WANG Marie HARUNA Shigeto TANIYAMA Atsushi HIGASHITANI Junji TERAO Takeshi NIKAWA Katsuyasu TACHIBANA

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.62, no.3, pp.178-184, 2016 (Released:2016-07-26)

参考文献数

34

被引用文献数

17

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Proinflammatory cytokines contribute to the progression of muscle wasting caused by ubiquitin-proteasome-dependent proteolysis. We have previously demonstrated that isoflavones, such as genistein and daidzein, prevent TNF-α-induced muscle atrophy in C2C12 myotubes. In this study, we examined the effect of dietary flavonoids on the wasting of muscle. Mice were divided into the following four groups: vehicle-injected (control) mice fed the normal diet (CN); tumor-bearing mice fed the normal diet (TN); control mice fed the isoflavone diet (CI); and tumor-bearing mice fed the isoflavone diet (TI). There were no significant differences in the intake of food or body weight gain among these four groups. The wet weight and myofiber size of gastrocnemius muscle in TN significantly decreased, compared with those in CN. Interestingly, the wet weight and myofiber size of gastrocnemius muscle in TI were nearly the same as those in CN and CI, although isoflavone supplementation did not affect the increased tumor mass or concentrations of proinflammatory cytokines, such as TNF-α and IL-6, in the blood. Moreover, increased expression of muscle-specific ubiquitin ligase genes encoding MAFbx/Atrogin-1 and MuRF1 in the skeletal muscle of TN was significantly inhibited by the supplementation of isoflavones. In parallel with the expression of muscle-specific ubiquitin ligases, dietary isoflavones significantly suppressed phosphorylation of ERK in tumor-bearing mice. These results suggest that dietary isoflavones improve muscle wasting in tumor-bearing mice via the ERK signaling pathway mediated-suppression of ubiquitin ligases in muscle cells.

著者

Madoka KOHNO Anayt ULLA Rina TANIGUCHI Akane OHISHI Kako HIRAYAMA Yuma TAKEMURA Shoichiro TAKAO Yuki KANAZAWA Yuki MATSUMOTO Masafumi HARADA Tomoya FUKAWA Hiro-omi KANAYAMA Takayuki UCHIDA Toshio SUZUKI Takeshi NIKAWA

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.6, pp.521-526, 2022-12-31 (Released:2022-12-31)

参考文献数

21

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Various dietary protein supplements are used by the elderly and bedridden to maintain their skeletal muscle mass and functions. High-quality proteins act as an anabolic driver and help to improve muscle strength and performance. Previously, we reported that soy protein significantly attenuates denervation-induced loss of muscle mass and myofiber cross sectional area in mice with inhibition of ubiquitination and degradation of IRS-1 in tibialis anterior muscle. It also increased muscle volume and strength in bedridden patients. In the present study, we investigated the effects of dietary soybean supplementation on muscle functions in taxi drivers lacking vigorous physical exercise. We conducted a case-control study on 25 healthy, male taxi drivers between the ages of 36 and 71 y performing minimal physical exercise. They were divided into two dietary groups: the soybean diet group (n=13) who ate daily meals (dinner) supplemented with 50 g of steamed soybean for 30 d and the control diet group (n=12) who received no soybean supplement. Next, we measured the muscle cross-sectional area (CSA) and muscle strength and function in both the groups before and after 30 d of soybean intake. The body weights of both diet groups did not differ significantly over time. However, after 30 d of soybean supplementation, the soybean-fed group developed significantly higher muscle CSA and grip strength compared to the control groups. In conclusion, dietary soybean supplementation improved muscle function in taxi drivers who lacked exercise.

著者

Nobuhiko TACHIBANA Masanori FUKAO Tomoko IRIE Yusuke IRISAWA Hirotaka SHIRONO Motoko OARADA Takeshi NIKAWA Tetsuya FUKAYA

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.66, no.5, pp.449-455, 2020-10-31 (Released:2020-10-31)

参考文献数

24

被引用文献数

2

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Although muscle atrophy can be caused by disuse and lifestyle-related syndromes, it may be possible to prevent this condition through dietary intervention. We hypothesized that a diet including red bell pepper juice (RBPJ) and soy protein isolate (SPI) would prevent muscle atrophy. Accordingly, an experimental diet containing RBPJ and/or SPI was administered for 18 d to normal C57BL/6J mice. The control group was administered a casein diet. Four days before the end of the test period, denervation-induced muscle atrophy and/or sham operation were performed. Anterior tibialis muscle samples were then obtained to assess muscle degradation and perform metabolome analysis. Under the denervation condition, the 20% SPI diet did not alter the mRNA expression levels of muscle atrophy marker genes compared with the 20% casein group. Although the diet comprising RBPJ and 20% casein did not prevent muscle atrophy compared with the control group, the diet containing RBPJ and 20% SPI did. Metabolome analysis revealed that a diet including RBPJ and SPI induced a greater than 1.5-fold change in the levels of 20 muscle atrophy-related metabolites. In particular, the level of S-adenosylmethionine, which concerned with energy metabolism and lifespan, showed a strong positive correlation with the muscle atrophy marker. These findings suggest that a diet including RBPJ and soy protein suppress gene expressions related with muscle atrophy. Further research in humans is needed to confirm whether a combination of RBPJ and SPI can indeed prevent muscle atrophy.