[关键词]
[摘要]
目的 探讨瑞舒伐他汀对骨质疏松大鼠腺苷酸活化蛋白激酶(AMPK)/沉默信息调节因子1(Sirt1)/核转录因子-κB(NF-κB)通路和骨微结构的影响。方法 将雌性SD大鼠随机分为假手术组、模型组、雌二醇(0.05 mg/kg)组、瑞舒伐他汀(1.0、2.0、4.0 mg/kg)组,每组12只。采用双侧卵巢切除术复制大鼠骨质疏松症模型。术后第9周雌二醇组和瑞舒伐他汀各剂量组ip相应药物,1次/d,连续给药12周。假手术组和模型组ip等体积生理盐水。ELISA法检测血清骨代谢标志物成骨特异性转录因子(CBF-α1)、Ⅰ型胶原交联羧基端肽(CTXI)、Ⅰ型前胶原氨基端原肽(PINP)、骨钙素(OC)水平和血清雌二醇(E2)、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)、白细胞介素1β(IL-1β)水平;Micro-CT扫描大鼠右侧股骨观察大鼠股骨远端骨微结构变化,分析骨小梁骨密度(BMD)、骨体积分数(BV/TV)、骨小梁数量(Tb.N)、骨小梁间隔(Tb.Sp)、骨小梁厚度(Tb.Th);苏木精–伊红(HE)染色观察骨组织形态学变化;Western blotting法检测骨组织Sirt1、AMPK、p-AMPK、NF-κB p65、NF-κ Bp65(acetyl K310)蛋白表达。结果 与假手术组相比,模型组大鼠血清E2、骨代谢相关标志物CBF-α1、CTX-Ⅰ、PINP、OC水平、BMD明显降低,炎症因子IL-6、TNF-α、IL-1β水平明显升高,骨小梁微结构参数BV/TV、Tb.N、Tb.Th明显降低,Tb.Sp明显升高(P<0.05),骨小梁出现断裂,排列疏松,骨组织p-AMPK/AMPK、Sirt1蛋白表达明显降低,NF-κB p65(acetyl K310)/NF-κB p65蛋白表达明显升高(P<0.05);与模型组相比,瑞舒伐他汀2.0、4.0 mg/kg组大鼠血清E2、骨代谢相关标志物CBF-α1、CTX-Ⅰ、PINP、OC水平、BMD明显升高(P<0.05),炎症因子IL-6、TNF-α、IL-1β水平下降,骨小梁微结构参数BV/TV、Tb.N、Tb.Th增加,Tb.Sp明显降低(P<0.05),新生骨小梁,形态相对完整;骨组织p-AMPK/AMPK、Sirt1蛋白表达明显升高,NF-κB p65(acetyl K310)/NF-κB p65蛋白表达明显降低(P<0.05)。结论 瑞舒伐他汀可改善骨质疏松大鼠的骨微结构,对骨质疏松具有保护作用,其作用机制可能与激活AMPK和Sirt1蛋白表达,降低NF-κB p65乙酰化水平有关。
[Key word]
[Abstract]
Objective To investigate the effects of rosuvastatin on AMP-activated protein kinase (AMPK)/silent information regulator 1 (Sirt1)/nuclear factor-κB (NF-κB) pathway and bone microstructure in osteoporosis rats.Methods Female SD rats were randomly divided into sham operation group, model group, estradiol (0.05 mg/kg) group and rosuvastatin (1.0, 2.0, and 4.0 mg/kg) groups, with 12 rats in each group. Osteoporosis (OP) model was established by bilateral ovariectomy. At 9th week after operation, the estradiol group and rosuvastatin groups were ip administered with corresponding drugs, once daily for 12 weeks. The sham operation group and model group were ip administered with equal volume of normal saline. After 12 weeks of administration, the samples were collected and related indexes were detected. The levels of serum core-binding factor α1 (CBF-α1), cross linked C-telopeptide of type Ⅰ collagen (CTXI), procollagen I N-terminal propeptide (PINP), osteocalcin (OC), estradiol (E2), interleukin-6 (IL-6), tumor necrosis factor (TNF-α), and interleukin-1β (IL-1β) were detected by ELISA method. The right femur of rats was scanned by Micro-CT, the changes of bone microstructure of distal femur were observed, and trabecular bone mineral density (BMD), bone volume fraction (BV/TV), trabecular number (Tb. N), trabecular septum (Tb.Sp), and trabecular thickness (Tb.Th) were analyzed. Hematoxylin eosin (HE) staining was used to observe the morphological changes of bone tissue. The protein expression of Sirt1, AMPK, p-AMPK, NF-κB p65, and NF-κB p65 (acetyl K310) was detected by Western blotting method.Results Compared with those in the sham operation group, the serum E2, CBF-α1, CTX-Ⅰ, PINP, OC, and BMD were significantly lower in the model group, the levels of inflammatory factors IL-6, TNF-α, and IL-1β were significantly higher, bone trabecular microstructure parameters BV/TV, Tb.N, and Tb.Th were significantly lower, Tb.Sp was significantly higher (P < 0.05), while the trabeculae were broken and arranged loosely, the protein expression of p-AMPK/AMPK and Sirt1 in bone tissue was significantly lower, and the protein expression of NF-κB p65 (acetyl K310)/NF-κB p65 was significantly higher (P < 0.05). Compared with those in the model group, the serum E2, CBF-α1, CTX-Ⅰ, PINP, OC, and BMD were significantly higher in the rosuvastatin 2.0 and 4.0 mg/kg groups, the levels of inflammatory factors IL-6, TNF-α, and IL-1β were significantly lower, bone trabecular microstructure parameters BV/TV, Tb.N, and Tb.Th were significantly higher, while Tb.Sp was significantly lower (P < 0.05), and new bone trabeculae could be seen with relatively complete shape. The protein expression of p-AMPK/AMPK and Sirt1 in bone tissue was significantly higher, but the protein expression of NF-κB p65 (acetyl K310)/NF-κB p65 was significantly lower (P < 0.05).Conclusion Rosuvastatin can improve the bone microstructure and protect osteoporosis in rats, which may be related to the activation of AMPK and Sirt1 protein expression and the decrease of NF-κB p65 acetylation level.
[中图分类号]
R965
[基金项目]
河南省医学科技攻关项目(202102310507)