Effects of fatty acids, nutrients and whole body vibration on bone histomorphometry, mechanical properties and metabolic parameters in male rat

The aims of this study are to investigate the effects of consumption of fatty acids, nutrients and application of vibration on bone histomorphometry and mechanical properties in addition to metabolic bone parameters in rat. Fifty six male Wistar rats were divided into seven independent groups and treated for 8 weeks as followings: (1) Control (received regular rat chaw food and drinking water); (2) RV (regular food + vibration); (3) SPM (regular food + vibration + calcium + vitamin D + boron); (4) CA (SPM + canola oil); (5) SU (SPM + sunflower oil); (6) CA + SU (SPM + Canola oil + Sunflower oil); and (7) CO (SPM + coconut oil). After 8 weeks, plasma samples were analyzed for vitamin D, parathyroid hormone, calcitonin, testosterone, free testosterone, and estrogen levels. The right femur bone was excised for histomorphometric and geometric analyses. The left femur and fifth lumbar vertebra were also used for evaluation of mechanical properties. Our results indicated that compact bone area and number of osteocytes in all treatment groups and energy to maximal load in RV compared to control group were significantly increased (P<0.05). The decline in trabecular separation area, femoral neck maximal load, and femoral neck stiffness in SPM compared to control, RV and both groups were significant (P<0.05). Also, several significant changes in spongy bone and trabecular separation areas, femoral neck maximal load and stiffness, lumbar maximal load and lumbar energy to maximal load between control and different treatment groups were detected (P<0.05). Decrease of trabecular separation area in CA, CA+SU, and CO groups compared to control group and femoral neck deformation in SU compared to CA group were significant. Finally, significant increase in estrogen level in CO group compared to all other groups was detected. Our findings demonstrated that combination of whole body vibration and coconut oil has beneficial effects on bone histomorphometry, mechanical properties and metabolic parameters.