Effect of habitual exercise on urinary liver-type fatty acid-binding protein levels in middle-aged and older adults.

The purpose of this study was to examine the effect of habitual exercise on urinary liver-type fatty acid-binding protein (L-FABP), which can reflect the degree of various stresses on renal proximal tubule related to the progression of renal disease, in middle-aged and older adults. Cross-sectional and interventional approaches were used to comprehensively achieve this purpose. In the cross-sectional study, we investigated the relationship between physical activity levels and urinary L-FABP levels in 130 middle-aged and older adults. In the interventional study, subjects (n=31) were divided into two groups: exercise (n=19) and control group (n=12), whereby we examined the effects of 12-week aerobic exercise training on urinary L-FABP levels. The cross-sectional study showed that the urinary L-FABP levels were significantly lower in the higher physical activity group than in the lower physical activity group (P<.05). In the interventional study, 12-week aerobic exercise training significantly decreased urinary L-FABP levels (P<.01). Furthermore, the relative changes in urinary L-FABP levels were significantly correlated with the relative changes in physical activity levels and mean arterial pressure after intervention (r=-.374 and r=.530, respectively). Our results revealed that the urinary L-FABP levels were lower in the higher physical activity individuals, and aerobic exercise training decreased urinary L-FABP levels. These results suggest that habitual exercise appears to be associated with a decrease in the degree of several stresses on renal proximal tubule and to be beneficial for kidney health in middle-aged and older adults.

Effects of Aerobic and Resistance Training Combined with Fortified Milk on Muscle Mass, Muscle Strength, and Physical Performance in Older Adults: A Randomized Controlled Trial.

OBJECTIVES: Fortified milk and resistance training (RT) increase muscle mass, muscle strength, and physical performance in older adults, but it remains unclear whether RT combined with aerobic training (AT) would have stronger effects on these outcomes. The purpose of this study was to examine the effects of aerobic and resistance training (ART) combined with fortified milk consumption on muscle mass, muscle strength, and physical performance in older adults. DESIGN: Open-labeled randomized controlled trial. SETTING: University of Tsukuba. PARTICIPANTS: Fifty-six older adults aged 65-79. INTERVENTION: Participants were randomly allocated into resistance training (RT + fortified milk, n = 28) and aerobic and resistance training (ART + fortified milk, n = 28) groups. All participants attended supervised exercise programs twice a week at University of Tsukuba and ingested fortified milk every day for 12 weeks. Skeletal muscle index ([SMI]: appendicular lean mass/height2) was assessed using dual-energy X-ray absorptiometry as a muscle mass measure. One-repetition maximum strength was measured using four kinds of resistance training machines (chest press, leg extension, leg curl, and leg press) as muscle strength measures. Sit-to-stand and arm curl tests were also assessed as physical performance measures. MEASUREMENTS: The primary measurements were muscle mass and strength. The secondary outcomes were physical performance, blood samples, habitual diet, habitual physical activity, and medication use. RESULTS: Although the muscle strength and physical performance measures significantly improved in both groups, SMI significantly improved in only the RT group. There was no significant difference in the change in SMI and muscle strength measures between the two groups. However, the change in sit-to-stand and arm curl measures in the ART group were significantly higher than those in the RT group. CONCLUSIONS: These results suggest that AT before RT combined with fortified milk consumption has similar effects on skeletal muscle mass and strength compared with RT alone, but it may be a more useful strategy to improve physical performance in older adults. Although the mechanism of our intervention is uncertain, our program would be an effective prevention for sarcopenia in older adults.

Disulfide linkage patterns of pig zona pellucida glycoproteins ZP3 and ZP4.

Zona pellucida, a transparent envelope surrounding the mammalian oocyte, plays major roles in fertilization and consists of three or four glycoproteins. Primary structures, and especially the positions of cysteine (Cys) residues in the zona glycoproteins, are well conserved among mammals. In this study, we analyzed the disulfide linkages of pig ZP3 and ZP4 purified from ovaries. While disulfide linkage patterns of four Cys residues in the N-terminal halves of the ZP domains of ZP3 and ZP4 were identical to those previously reported for mice, rats, humans, and fish, the disulfide linkage patterns of six Cys residues in the C-terminal half of the ZP domain in ZP4, as well as eight Cys residues in the C-terminal region of the ZP domain and a following region unique to ZP3, were different from those previously reported. Thus, higher-order structures of zona glycoproteins might not be conserved in the C-terminal regions.