伊班膦酸钠对大鼠膝骨关节炎关节软骨及软骨下骨的影响

目的观察伊班膦酸钠对大鼠膝骨关节炎关节软骨及软骨下骨的影响,并从MAPKs信号通路探讨其作用机制。方法将30只3月龄SD雄性大鼠随机分成3组(每组10只)。假手术组、前交叉韧带切断术组(ACLT组)、前交叉韧带切断术+伊班膦酸钠治疗组(治疗组)。其中ACLT组及治疗组均行ACLT术(膝关节前交叉韧带切断术)处理。术后1w,治疗组予以腹腔注射伊班膦酸钠10μg/kg,1 w 1次,共12 w;ACLT组腹腔注射生理盐水,剂量参照伊班膦酸钠,1w 1次,共12 w。12 w后处死动物,对关节软骨行Mankin评分、软骨下骨显微CT及骨组织定量分析、以及对MAPKs信号通路和MMP-13 mRNA表达水平进行分析。结果 1ACLT组的骨体积分数(BV/TV)、骨小梁数量(Tb.N)显著低于假手术组(P0.05、P0.05),骨小梁厚度(Tb.Th)两组之间差异无明显统计学意义、而骨小梁间隔(Tb.Sp)显著高于假手术组(P0.01);治疗组骨体积分数(BV/TV)、骨小梁数量(Tb.N)明显高于ACLT组(P0.05、P0.05),骨小梁厚度(Tb.Th)两组之间差异无明显统计学意义,而骨小梁间隔(Tb.Sp)显著低于ACLT组(P0.05)。2ACLT组的Mankin评分明显高于假手术组(P0.01);治疗组的Mankin评分明显低于ACLT组(P0.05)。3ACLT组中MAPKs信号通路(C-JUN、ERK1及P38)和MMP-13水平明显高于假手术组(P0.01、P0.01、P0.01、P0.01);治疗组的MAPKs信号通路(C-JUN、ERK1及P38)和MMP-13水平明显低于ACLT组(P0.01、P0.01、P0.01、P0.01)。结论伊班膦酸钠可能通过调控MAPKs信号通路的机制缓解大鼠膝骨关节炎关节软骨退变,并且抑制软骨下骨的骨质疏松。

Effect of ibandronate sodium on the articular cartilage and subchondral bone in rat model of knee osteoarthritis

Objective To observe the effect of ibandronate sodium on articular cartilage and the subchondral bone in a rat model of knee osteoarthritis, and to investigate whether the mechanism of ibandronate sodium is via the MAPKs signal pathway. Methods Thirty 3-month-old male SD rats were randomly divided into 3 groups (10 rats in each group): Sham-operated group, anterior cruciate ligament transection (ACLT) with intraperitoneal injection of saline (ACLT group), and anterior cruciate ligament transection with intraperitoneal injection of ibandronate sodium (the treatment group). One week after ACLT, rats in the treatment group received intraperitoneal injection of ibandronate sodium 10ug/kg once a week for 12 weeks. Rats in the ACLT group were injected with normal saline. The rats were sacrificed in 12 weeks. Mankin score was used to evaluate the cartilage of the joint. Micro-computed tomography and histology analysis were performed to evaluate subchondral micro-architecture. The expression of MMP-13 mRNA, a signal of MAPKs pathway, was determined. Results (1) The bone volume fraction (BV/TV) and trabecular bone number (Tb.N) in ACLT group were significantly lower than those in Sham-operated group (P<0.05). Trabecular thickness (Tb.Th) was not statistically different between the two groups. Trabecular separation (Tb.Sp) was significantly higher in ACLT group than that in Sham-operated group (P<0.01). BV/TV and trabecular number (Tb.N) in treatment group were significantly higher than those in ACLT Group (P<0.05). Tb.Th was not statistically different between the two groups. Tb.Sp was significantly lower in treatment group than that in ACLT group (P<0.05). (2) The Mankin score in ACLT group was significantly higher than that in Sham-operated group (P<0.01). The Mankin score in treatment group was significantly lower than that in ACLT group (P<0.05). (3) The molecules in MAPKs signal pathway (C-JUN, P38, and ERK1) and MMP-13 levels in ACLT group were significantly higher than those in Sham-operated group (P<0.01). The molecules in MAPKs signal pathway (C-JUN, ERK1, and P38) and MMP-13 levels in treatment group were significantly lower than those in ACLT group (P<0.01). Conclusion Ibandronate sodium inhibits subchondral bone loss and articular cartilage degeneration in ACLT rats, at least partially, by inhibiting MAPKs signaling pathway.