Basic Study to Review Whether Dietary Modifications for the Repression of the Body-fat Accumulation, Muscle-mass Loss and Bone Mineral Density （BMD） Loss in Postmenopausal Women: Effects of Dietary Amino Acid Supplements to the Diet on Muscle-mass, Femoral Bone Mineral Density and Running Activity of the Ovariectomized Adult Rats under Food-restriction

The present study aims to review whether dietary modifications will prevent body fat accumulation, muscle mass wasting and bone mineral density loss in postmenopausal women who incorporate physical exercise into daily life. 9-week-old ovariectomized Wistar strain female rats were divided into four groups: CA-Ex, Gln-Ex, Leu-Ex and CitD-Ex. Depending on which group they were in, the rats were given a 20％ casein protein based experimental diet supplemented with nothing （control diet, CA-Ex）; 5％ of L-glutamine （Gln-Ex）; 5％ of L-leucine （Leu-Ex）; or 2.5％ of L-citrulline＋2.5％ of D-serine （CitD-Ex）, each 11 g per day for 10 weeks. All of these rats were housed in individual cage with a running wheel for 10 weeks. A sham operation was carried out on another group of rats （Sham） and were given the same diet as CA-Ex, the control diet. Results were as follows: 1） Uterus weights of the ovariectomized rats, that is group CA-Ex, Gln-Ex, Leu-Ex and CitD-Ex, appeared to show lower values than that of the group Sham. 2） No significant differences were observed in a）changes in body weight, b）blood analyses, c）liver, kidney, uterus and muscle weights, and d）femoral-bone mineral density in groups Gln-Ex, Leu-Ex, and CitD-Ex as compared to the group CA-Ex. 3） Relatively higher running activity was observed in group CitD-Ex than that of group CA-Ex. This observation suggests that increasing dietary L-citrulline plus D-serine in postmenopausal rats may lead to an increase in physical activity. Further research is needed to understand the physiological and nutritional significance of the unexpected results that dietary amino acid may accelerate the physical activity.departmental bulletin pape