积雪草酸对小鼠骨折愈合的影响研究

Effect of asiatic acid on fracture healing in mice

摘要:

目的：探讨高低2种剂量积雪草酸对小鼠骨折愈合的影响。方法：对36只12周龄C57小鼠麻醉后行右侧股骨骨折术。骨折术后实验分为3组，每组12只，分别是：空白对照组，给予生理盐水（0.2 mL）每周2次皮下注射；低剂量积雪草酸组，给予低剂量积雪草酸水溶液（5 μg/g，0.2 mL）每周2次皮下注射；高剂量积雪草酸组，给予高剂量积雪草酸水溶液（15 μg/g，0.2 mL）每周2次皮下注射。术后给药前和给药后8周行右下肢X线摄像。给药后8周进行取材，行微型计算机断层扫描分析、三点弯曲力学测试和脱钙骨组织形态学分析。结果：经过8周治疗后，各组均呈现不同程度愈合。X线影像结果提示，空白对照组和低剂量积雪草酸治疗组骨痂生长不完全，高剂量积雪草酸治疗组骨痂形成较完整，骨小梁密度均匀；微型计算机断层扫描分析定量结果显示，与空白对照组相比，低剂量积雪草酸治疗组骨组织体积百分数和骨密度分别升高13.0%（P=0.264）或7.6%（P=0.215），而高剂量积雪草酸组骨组织体积百分数和骨密度分别升高28.3%（P=0.020）或15.8%（P=0.009）。股骨生物力学结果提示，与空白对照组相比，积雪草酸治疗有助于提高股骨生物力学性能，低剂量组最大载荷和杨氏模量分别增加26.37%（P=0.025）和10.00%（P=0.183），高剂量组最大载荷和杨氏模量分别增加42.89%（P=0.007）和25.19%（P=0.035）。形态学结果提示，空白对照组骨折端未完全愈合且矿化不完全，接受高低2种剂量积雪草酸治疗的骨折区矿化完全，高剂量组骨组织修复效果较为理想。结论：高剂量积雪草酸有助于加速小鼠股骨骨折骨化和愈合，并提高其生物力学性能。

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.