ABSTRACT
OBJECTIVES: To examine the effects of whole body vibration (WBV) on bone properties in growing rats, and to explore the optimal conditions for enhancing bone properties. METHODS: Thirty-six 4-week-old male rats were divided into 1 control and 5 experimental groups. Each experimental group underwent WBV at 15, 30, 45, 60, and 90 Hz (0.5 g, 15 min/d, 5 d/wk) for 8 weeks.We measured bone size, muscle weight and bone mechanical strength of the right tibia. Trabecular bone mass and trabecular bone microstructure (TBMS) of the left tibia were analyzed by micro-computed tomography. Serum levels of bone formation/resorption markers were also measured. RESULTS: WBV at 45 Hz and 60 Hz tended to enhance trabecular bone mass and TBMS parameters. However, there was no difference in maximum load of tibias among all groups. Serum levels of bone resorption marker were significantly higher in the 45-Hz WBV group than in the control group. CONCLUSIONS: WBV at 45–60 Hz may offer a potent modality for increasing bone mass during the period of rapid growth. Further studies are needed to explore the optimal WBV conditions for increasing peak bone mass and TBMS parameters. WBV modality may be a potent strategy for primary prevention against osteoporosis.
Subject(s)
Animals , Humans , Male , Rats , Bone Resorption , Osteoporosis , Primary Prevention , Tibia , VibrationABSTRACT
Aim To investigate the effect of curcumin against high-fat-diet induced C57BL/6J mice bone changes and the correlation between the expression of cathepsin K and curcumin.Methods Curcumin treated C57BL/6J mice had been on high fat diet for 12 weeks.The HE, Alizarin red S staining and Safranin O/fast green staining of femur were employed to evaluate bone microstructure, bone metabolism and bone development.The expressions of cathepsin K were assessed by Western blot and immunohistochemical staining.Results Histopathological results showed that curcumin could improve the destruction of trabecular bone structure, cartilage development and bone calcification.Biomechanical results proved that curcumin could improve the bone strength of the type 2 diabetic mice induced by high fat.The results of immunohistochemistry and Western blot assay indicated that curcumin could significantly inhibit the expression of cathepsin K in bone tissues of mice.Conclusion Curcumin can increase bone strength, improve bone microstructure, and enhance the degree of bone calcification, which may be achieved by inhibiting the expression of cathepsin K.
ABSTRACT
This study investigated how different treadmill running periods effected bone mechanical strength in ovariectomized mice. Eighty female ICR mice aged 12-weeks-old were used. All mice were divided into 8 groups (<i>n</i>=10) randomly, and had either a sham-operation (<i>n</i>=10) or an ovariectomy (<i>n</i>=70). The SHAM group and one OVX group (NR) were used as non-running control groups, with the remainder comprising the treadmill running groups : the LA (8 m/min), MA (16 m/min), and HA (24 m/min) groups which ran for 12 weeks, and the LB (8 m/min), MB (16 m/min), HB (24 m/min) groups which ran for 6 weeks for 25 min on 5 days/week. After this experiment, maximum loads for the femur and tibia were measured by three-pointed bending test, and the bone mechanical strength of the bones was calculated. Also, the dry bone weight and ash content of the bones were measured. Maximum femur and tibia load and bone mechanical strength were affected by running speed and term significantly. Maximum load and bone mechanical strength of tibia were shown as an interaction. Bone mechanical strength in all running groups was higher than that in the NR group, significantly. This study suggested that treadmill running prevented a reduction of bone mechanical strength, and that treadmill running was most effective in the LA and MA groups (running at low and medium speed and for a long period).