EPCs移植对去卵巢大鼠骨质疏松的影响

Effect of EPCs transplantation on osteoporosis in ovariectomized rats

目的研究EPCs移植对去卵巢大鼠骨质疏松的影响。方法将雌性未孕Wistar大鼠60只完全随机分为假手术组、模型组及EPCs组,每组20只。术后1周时行尾静脉注射治疗,连续注射7 d。定时测大鼠体重,13周时通过ELISA法检测血清25-羟基维生素D[25(OH)D]、骨特异性碱性磷酸酶(BAP)、Ⅰ型胶原C端肽(CTX-Ⅰ)及抗酒石酸酸性磷酸酶5b(TRAP5b)含量;运用RT-PCR、Western Blot检测椎体TGF-β/Smads表达变化。进一步行骨密度、骨钙含量及生物力学性能测定,通过HE染色观察病理变化。结果造模后8周起,模型组体重较假手术组明显升高(P<0.05);EPCs组体重与模型组比较明显降低(P<0.05);模型组骨密度及骨钙含量较假手术组明显降低(P<0.05);EPCs组骨密度和骨钙含量较模型组显著升高(P<0.05);与假手术组比较,模型组血清25(OH)D、BAP水平降低,CTX-Ⅰ、TRAP5b的水平升高(P<0.05);与模型组比较,EPCs组血清25(OH)D、BAP水平升高,CTX-Ⅰ、TRAP5b水平降低(P<0.05)。生物力学检测表明,模型组极限载荷、极限应力和弹性模量明显低于假手术组(P<0.05),EPCs组的极限载荷和弹性模量比模型组显著增高(P<0.05)。HE染色显示EPCs移植后大鼠骨质疏松减轻。与模型组相比,EPCs组TGF-β1、Smad2、Smad3的表达显著升高(P<0.05)。结论EPCs移植可能通过调控TGF-β/Smads通路发挥治疗去卵巢大鼠骨质疏松症的作用。

Objective To investigate the therapeutic effect of EPCs transplantation on ovariectomized osteoporotic rats.Methods Sixty female non-pregnant Wistar rats were randomly divided into sham operation group,model group and EPCs group,with 20 rats in each group.One week after operation,tail vein injection was given for 7 days.The weight of rats was measured regularly.At 13 weeks,serum 25-hydrozyvitamin D[25(OH)D],bone alkaline phosphatase(BAP),typeⅠcollagen C-terminal peptide(CTX-Ⅰ)and tartrate-resistant acid phosphatase 5 b(TRAP 5 b)were detected by ELISA.The expression of TGF-beta/Smads in vertebral body was detected by RT-PCR and Western Blot.Further assessments included bone mineral density,bone calcium content and biomechanical properties,and pathological changes were observed by HE staining.Results 8 weeks after modeling,the weight of the model group was significantly higher than that of the sham operation group(P<0.05).The weight of the EPCs group was significantly lower than that of the model group(P<0.05).Bone mineral density and bone calcium content in the model group were significantly lower than those in the sham operation group(P<0.05).Bone mineral density and bone calcium content in the EPCs group were significantly higher than those in the model group(P<0.05).Compared with the sham operation group,the serum levels of 25(OH)D and BAP in the model group were decreased,and the levels of CTX-Ⅰand TRAP5 b were increased(P<0.05).Compared with the model group,serum levels of 25(OH)D and BAP increased,and levels of CTX-Ⅰand TRAP 5 b decreased in the EPCs group(P<0.05).Biomechanical tests showed that the ultimate load,ultimate stress and elastic modulus of the model group were significantly lower than those of the sham operation group(P<0.05).The ultimate load and elastic modulus of the EPCs group were significantly higher than the model group(P<0.05).HE staining showed a reduction in osteoporosis in rats after EPCs transplantation.Compared with the model group,the expression of TGF-β1,Smad2 and Smad3 in EPCs group was significantly increased(P<0.05).Conclusion EPCs transplantation may play a role in the treatment of osteoporosis in ovariectomized rats by regulating the TGF-β/Smads pathway.