冬凌草甲素降低糖皮质激素诱导的大鼠股骨颈骨折风险

Oridonin in the reduction of the risk of glucocorticoid induced femoral neck fracture in rats

目的观察冬凌草甲素(ORI)对糖皮质激素诱导的大鼠股骨颈骨折风险的影响。方法将30只4月龄SPF级SD大鼠随机分为对照组(n=10)、地塞米松皮下注射组(DEX组,n=10)、地塞米松皮下注射+ORI补充组(DEX+ORI组,n=10)。对照组给予0.1 ml生理盐水肌内注射;DEX组按照1 mg/kg剂量行肌内注射,每周2次。DEX+ORI组自DEX注射(同DEX组)的第1天起,即予以腹腔注射ORI(剂量2 mg/kg,每周2次)。上午8:00准时给药,共计8周。8周后,对所有大鼠进行血清学、骨密度、骨微形态学、生物力学检测,并比较各组间差异。结果与对照组比较,DEX组大鼠血清中Ⅰ型前胶原氨基末端前肽(P1NP)水平,腰椎、股骨、胫骨的骨密度,股骨干微形态指标(骨体积分数、骨小梁数目、骨小梁厚度)和生物力学指标(股骨颈极限载荷、刚度、骨折强度)均明显降低(P<0.05),血清Ⅰ型胶原羧基端肽(CTX-1)水平、骨小梁分离度、结构模式指数明显升高(P<0.05)。与DEX组比较,DEX+ORI组血清P1NP,腰椎、股骨、胫骨的骨密度,股骨干微形态指标(骨体积分数、骨小梁数目、骨小梁厚度)和生物力学指标(股骨颈极限载荷、刚度、骨折强度)明显升高(P<0.05)、血清CTX-1水平、骨小梁分离度、结构模式指数明显降低(P<0.05)。结论ORI能够有效预防糖皮质激素诱导的大鼠股骨颈骨折,增加骨强度和骨密度,有效降低股骨颈骨折风险。

Objective To observe the effect of oridonin(ORI)on the risk of femoral neck fracture induced by glucocorticoid in rats.Methods Thirty 4-month-old SPF SD rats were randomly divided into control group,dexamethasone(DEX)group,and DEX+ORI group(n=10,each).The control group was given intramuscular injection of 0.1 ml normal saline;the DEX group was given intramuscular injection of dexamethasone(1 mg/kg,twice a week).In DEX+ORI group,oridonin(2 mg/kg,twice a week)was injected intraperitoneally from the first day of intramuscular injectin of dexamethasone(1 mg/kg,twice a week).The drug was given at 8:00 for 8 weeks.After 8 weeks,the serum indexes,bone mineral density(BMD),bone microstructuk and biomechanical indexs of all rats were detected and compared.Results Compared with the control group,serum procollagen type I N-terminal propeptide(P1 NP)level,BMD of lumbar spine,femur and tibia,microstructure indexs(bone volume fraction,number of trabeculae,thickness of trabecular bone)and biomechanical indexs(ultimate load,stiffness and fracture strength of femoral neck)in DEX group were significantly decreased(P<0.05),and serum C-telopeptide of type I collagen(CTX-1)level,trabecular separation degree and structural pattern index were significantly increased(P<0.05).Compared with DEX group,serum P1 NP level,BMD of lumbar spine,femur and tibia,microstructure indexs(bone volume fraction,trabecular number,trabecular thickness),and biomechanical indexs(ultimate load,stiffness and fracture strength of femoral neck)in DEX+ORI group were significantly increased(P<0.05),serum CTX-1 level,trabecular separation degree and structural pattern index were significantly decreased(P<0.05).Conclusion Oridonin can effectively prevent the risk of femoral neck fracture induced by glucocorticoid,increase bone strength and BMD,and effectively reduce the risk of femoral neck fracture.