Effect of asiatic acid on fracture healing in mice

Abstract:

Objective：To investigate the effect of two different dosages asiatic acid on the fracture healing in mice. Methods：Thirty-six C57 mice of 12 weeks were suffered right femoral fracture and were divided into three groups（n=12）：the blank control group which was treated with saline of 0.2 mL；the low-dose asiatic acid group which was treated with asiatic acid at a dose of 5 μg/g and amount of 0.2 mL；high-dose asiatic acid group which was treated with asiatic acid at a dose of 15 μg/g and amount of 0.2 mL. All treatments were performed twice a week via subcutaneously in－jections. X-ray images of the right lower limb were performed before and 8 weeks after drug administration. After 8 weeks of administration，micro-computer tomography（CT） analysis，three-point bending mechanical test and decalcified bone histological analysis were performed. Results：After 8 weeks of treatment，healing in three groups was in different degree. X-ray data showed that callus formation was incomplete in the blank control group and the low-dose asiatic acid group；callus formation was com－plete and density of trabecular bone was uniformly in the high-dose treatment group. Results of micro-CT showed that the bone volume ratio（BV/TV） or bone mineral density（BMD） in the low-dose treatment group was increased by 13.0%（P=0.264） or 7.6%（P=0.215） than that in the blank control. In addition，BV/TV or BMD in the high-dose treatment group was also increased by 28.3%（P=0.020） or 15.8%（P=0.009） than that in the blank control. Data of the mechanical test showed that asiatic acid was able to enhance the femur’s mechanical property；maximal load and Young’s modulus were increased by 26.37%（P=0.025） and 10.00%（P=0.183） in the low-dose group or 42.89%（P=0.007） and 25.19%（P=0.035） in the high-dose group. And histological results showed that mineralization was incomplete and non-union at the fracture ends inside the callus in the control group，while mineralization was complete in two asiatic acid treatment groups，with a better bone healing effect in the high-dose group. Conclusion：The high dose of asiatic acid can promote the ossification and accelerate the healing process of fracture，and enhance the mechanical properties in mice.