Effects of low-carbohydrate diet and resistance exercise training on physical characteristics and concentrations of plasma metabolites and hormones / 体力科学

We clarify the effect of combination of low-carbohydrate diet and resistance exercise training on physical characteristics and plasma concentrations of metabolites and hormones in humans. Intervention of low-carbohydrate diet and resistance exercise training were performed on 7 healthy men and 3 women (age 39.6 ± 7.0 year; BMI 25.1 ± 3.6 kg/m2) for 8 - 12 weeks. Physical characteristics and 106 test items including and blood concentrations of metabolites and hormones were measured before and after the intervention. The effects of intervention were analyzed by a paired t-test, in which multiple testing was corrected by the method of Storey (significant variation q <0.1). In both men and women, carbohydrate and energy intake per day were low, and protein intake per day was almost the same as the recommended dietary allowance. Because carbohydrate intake were limited (174 kcal), resulting in reduction of total energy (1186 kcal). After the intervention, body weight, BMI (Body Mass Index), fat mass, body fat, muscle mass and body water content significantly decreased, while muscle mass per body mass significantly increased. Glycine, 3-methyl histidine, inorganic phosphorous, urea nitrogen, urea nitrogen per creatinine, were significantly increased, while HbA1c, white blood cell count, β-aminoisobutyric acid, adrenalin, free T4, blood ammonia, γGTP, cholinesterase, and leptin were decreased.

Effects of teriparatide on bone in autochthonous transgenic model mice for diabetes mellitus (Akita mice)

OBJECTIVES@#The purpose of this study is to evaluate the effects of teriparatide (TPTD) on bone mineral density (BMD), bone strength, and bone quality in Akita mouse models of diabetes mellitus.@*METHODS@#Twelve-week-old female Akita mice and control mice (C57/BL/6NCrSlc) were divided into 4 groups: control mice treated with vehicle (n = 7) or TPTD (n = 6); and Akita mice treated with vehicle (n = 6) or TPTD (n = 7). TPTD or vehicle was administered subcutaneously 3 times a week for 8 weeks. Blood glucose, serum sclerostin, total tibial BMD, femoral shaft bone strength, and bone quality using Fourier-transform infrared spectroscopy imaging were evaluated.@*RESULTS@#No significant differences in serum sclerostin levels were evident among these groups after 8 weeks of treatment. TPTD significantly increased BMD in control mice (+12.7%, P = 0.02) and Akita mice (+29.2%, P = 0.001) compared with vehicle. Maximum load and stiffness were significantly higher in Akita mice treated with TPTD than in Akita mice treated with vehicle (+56.6%, P = 0.03 and + 90.5%, P = 0.02, respectively). On Fourier-transform infrared spectroscopy imaging, the mineral/matrix ratio was significantly lower in Akita mice treated with vehicle than in control mice (−12.2%, P = 0.02), and TPTD treatment significantly increased the mineral/matrix ratio (P = 0.003).@*CONCLUSIONS@#TPTD thus improved BMD and bone strength in both control mice and Akita mice, with improvements in the mineral/matrix ratio among Akita mice.

Effects of combined therapy of alendronate and low-intensity pulsed ultrasound on metaphyseal bone repair after osteotomy in the proximal tibia of glucocorticoid-induced osteopenia rats

OBJECTIVES: Glucocorticoid (GC) treatment inhibits activation of runt-related transcription factor 2 (Runx2), which is essential for osteoblast differentiation from stem cells. As a result, GC treatment results in bone loss, GC-induced osteoporosis (GIO), elevated fracture risk, and delayed bone healing. Bisphosphonates such as alendronate (ALN) are recommended for treating or preventing GIO, and lowintensity pulsed ultrasound (LIPUS) facilitates fracture healing and maturation of regenerated bone. Combined therapy with ALN and LIPUS may stimulate cancellous bone healing in GIO rats. Here, we examined the effect of ALN and LIPUS on cancellous bone osteotomy repair in the proximal tibia of GIO rats. METHODS: Prednisolone (10 mg/kg body weight/day) was administered for 4 weeks to induce GIO in 6-month-old female Sprague-Dawley rats. Tibial osteotomy was then performed and daily subcutaneous injection of ALN (1-µg/kg body weight) was subsequently administered alone or in combination with LIPUS (20 min/day) for 2 or 4 weeks. RESULTS: ALN significantly increased bone mineral density (BMD) at 2 and 4 weeks, and ALN + LIPUS significantly increased BMD at 4 weeks. Bone union rates were significantly increased after 2 and 4 weeks ALN and ALN + LIPUS treatment. Lastly, ALN and ALN + LIPUS significantly increased the proportion of Runx2 positive cells at 4 weeks. CONCLUSIONS: ALN monotherapy and combined ALN and LUPUS treatment augmented BMD and stimulated cancellous bone repair with increased Runx2 expression at the osteotomy site in GIO rats. However, the combined treatment had no additional effect on cancellous bone healing compared to ALN monotherapy.

Direct Determination of Trace Nitrogen Dioxide by Atmospheric Pressure Ionization Mass Spectrometry(APIMS)without Conversion to Nitric Oxide

The aim of this study was to develop a new method for the determination of NO2 levels encountered in clinical settings as well as in environmental studies, using a bi−component atmospheric pressure ionization mass spectrometry(APIMS). Hydrogen (1%) diluted in pure argon was ionized by corona discharge in the first ionization component. Fifty ml of the analyte diluted in 250ml of composite air or carbon dioxide (CO2) was introduced into the second ionization component and analyzed. When composite air was used as the sample carrier gas, NO in the analyte was oxygenated and there was an increase in the NO2 content from that in the original analyte. However, when CO2 was used as the sample carrier gas, the level of NO2 in the analyte could be determined because CO2 did not change the NO2 content from that in the original analyte. A calibration curve with good linearity was obtained using the UG−410 APIMS system, with a regression equation of Y(%)=5.513*10-2 X(ppb) and a detection limit of 0.9ppb. Since APIMS detects NO2 directly within its system, the concentration of NO does not need to be measured. This system may be of great help in the accurate detection and determination of the concentration of low levels of NO2 during inhaled NO therapy