METHODS: Thirty-five male rats were included in five groups: plain polymethyl methacrylate (PMMA), estrogen-impregnated PMMA (E+PMMA), bone chip added PMMA (BC+PMMA), hydroxyapatite-coated PMMA (HA) and calcium phosphate cement (CPC). The levels of bone alkaline phosphatase (BALP), osteocalcin (OC), and tumor necrosis factor-alpha (TNF-α) were analyzed in intracardiac blood samples collected at the end of 4 weeks of the right femur CSD intervention. All IMs collected were fixed and prepared for histopathological scoring. The tissue levels of rat-specific Transforming Growth Factor-Beta (TGF-β), Runt-related Transcription Factor 2 (Runx2), and Vascular Endothelial Growth Factor (VEGF) were analyzed immunohistochemically.
RESULTS: Serum levels of BALP and OC were significantly higher in E+PMMA and BC+PMMA groups than those of other groups (P = 0.0061 and 0.0019, respectively). In contrast, TNF-α levels of all groups with alternative bone cement significantly decreased compared to bare PMMA (P = 0.0116). Histopathological scores of E+PMMA, BC+PMMA, and CPC groups were 6.86 ± 1.57, 4.71 ± 0.76, and 6.57 ± 1.51, respectively, which were considerably higher than those of PMMA and HA groups (3.14 ± 0.70 and 1.86 ± 0.69, respectively) (P < 0.0001). Significant increases in TGF-β and VEGF expressions were observed in E+PMMA and CPC groups (P = 0.0001 and <0.0001, respectively) whereas Runx2 expression significantly increased only in the HA group compared to other groups (P < 0.0001).
CONCLUSIONS: The modified PMMA with E and BC, and CPC as an alternative spacer resulted in a well-differentiated IM and increased IM progression by elevating BALP and OC levels in serum and by mediating expressions of TGF-β and VEGF at the tissue level. Estrogen-supplemented cement spacer has yielded promising findings between modified and alternative bone cement.
方法:将35只雄性大鼠分为五组:普通聚甲基丙烯酸甲酯(PMMA),雌激素浸渍PMMA(E+PMMA),骨芯片添加PMMA(BC+PMMA),羟基磷灰石涂层PMMA(HA)和磷酸钙骨水泥(CPC)。骨碱性磷酸酶(BALP)的水平,骨钙蛋白(OC),和肿瘤坏死因子-α(TNF-α)在右股骨CSD干预4周结束时收集的心内血液样本中进行分析。将收集的所有IM固定并准备进行组织病理学评分。大鼠特异性转化生长因子-β(TGF-β)的组织水平,Runt相关转录因子2(Runx2),对血管内皮生长因子(VEGF)进行免疫组化分析。
结果:E+PMMA组和BC+PMMA组血清BALP和OC水平明显高于其他组(P分别为0.0061和0.0019)。相比之下,与裸露的PMMA相比,使用替代骨水泥的所有组的TNF-α水平均显着降低(P=0.0116)。E+PMMA的组织病理学评分,BC+PMMA,和CPC组分别为6.86±1.57,4.71±0.76和6.57±1.51,显著高于PMMA组和HA组(分别为3.14±0.70和1.86±0.69)(P<0.0001)。在E+PMMA和CPC组中观察到TGF-β和VEGF表达的显著增加(分别为P=0.0001和<0.0001),而与其他组相比,Runx2表达仅在HA组中显著增加(P<0.0001)。
结论:用E和BC修饰的PMMA,和CPC作为替代间隔区导致分化良好的IM,并通过升高血清中BALP和OC的水平以及在组织水平介导TGF-β和VEGF的表达来增加IM的进展。补充雌激素的水泥垫片在改性和替代骨水泥之间产生了有希望的发现。