The pathophysiology of sarcopenia is complex and must be further explored. While metabolic acidosis may be a risk factor for sarcopenia, it remains unclear whether acidic urine is related to sarcopenia. The purpose of the present study was to investigate the association between sarcopenia and urine pH in the elderly.An elderly population (n = 123 [male = 46]; mean age = 81.7 years) was classified into 2 groups based on the sarcopenia status according to their strength, requirement of assistance in walking, their ability to rise from a chair their ability to climb stairs, and their history of falls. Urinalysis was measured using dipstick tests.The sarcopenia group (n = 32) was significantly older, had less exercise habit and showed a lower urine pH (mean pH = 5.5) in comparison to the nonsarcopenia group (mean pH = 6.2, P < .01). A multivariate analysis that was adjusted for age, male sex, body mass index, uro-renal variables and exercise habit revealed that urine pH (odds ratio, 0.43; 95% confidence interval, 0.22-0.85, P = .02), age and less exercise habit were independently and significantly associated with sarcopenia.The findings of the present study suggest a potential association between metabolic acidosis and the pathophysiology of sarcopenia in the elderly. As urine pH is a simple biomarker that can be obtained using dipstick tests, it is therefore expected to be helpful for detecting sarcopenia in the clinical setting.Abbreviations: BMI = body mass index, GFR = glomerular filtration rate, SARC-F = strength, assistance in walking, rising from a chair, climbing stairs, and falls.

The present study aimed to assess if there is a gender difference in thermal perception, and estrogen is involved in the mechanism. MethodsMale (M group) and female ICR mice were used (n=6 and 18, respectively). Each mouse was placed a device for temperature measurement in the abdominal cavity under general anesthesia. Female mice were divided to three groups: two groups were bilaterally ovariectomized with and without estradiol replacement (E2 and N groups) and one sham‐operated (F group). Mice were placed in an experiment box (50x12x15 cm), of which 5 Pertier boards at the bottom. Each board temperature was controlled by computer program, and changed each 6 min for 90 min. The temperature was selected from either of 28°C, 31°C, 34°C, 37°C, and 40°C with a difference from that of the other boards. Abdominal temperature (Tabd) and the position of a mouse and its board temperature were recorded every 1 min. Experiment was started after 60‐min baseline period with all boards set at 34°C. Mice were habituated to the box 2‐3 times before the experiment. ResultsDuring the housing period before the experiment, there were no differences in Tabd among the groups; however, during the experiment, Tabd was higher in the F group than in the M group. In addition, the F group preferred 40°C board, but the M group 34°C board. There were no differences in Tabd and temperature preference of the board among the F, E2 and N groups. Conclusion In this experimental condition, male mice showed higher environmental condition than female mice. However, estradiol is not likely mechanism for the difference. Grant Funding Source: MEXT.KIBANKEISEI