激素对兔骨髓间充质干细胞神经递质表达的影响

Steroid effects on neurotransmitter expressions in bone marrow mesenchymal stem cells of rabbits

背景:激素性股骨头坏死的确切发病机制仍未清楚,研究发现神经系统可通过多种途径调控骨髓间充质干细胞的分化,激素可能通过影响其调控机制而引起骨坏死。目的:观察在激素作用下,骨髓间充质干细胞中神经递质或其受体mRNA表达的变化。方法:密度梯度离心和贴壁培养获得兔骨髓间充质干细胞。将传代培养的第3代细胞随机分为两组,实验组加入浓度为10-7mol/L的地塞米松,对照组正常培养。分别于诱导后第4,7,11,15天,测定细胞中神经生长因子、成纤维细胞生长因子、降钙素相关基因肽受体、血管活性肠肽受体、P物质受体及过氧化物酶体增殖子活化受体γ的mRNA表达。结果与结论:实验组神经生长因子、成纤维细胞生长因子、降钙素相关基因肽受体、血管活性肠肽受体和P物质受体的mRNA表达较对照组明显降低,而过氧化物酶体增殖子活化受体γmRNA表达较对照组明显增高,差异均具有显著性意义(P<0.01),实验组各因子在不同时间点间进行比较却无明显差异(P>0.05)。结果表明大剂量激素可使骨髓间充质干细胞中具有成骨或成血管作用的神经递质或其受体表达下降,这可能与激素性股骨头坏死发生的机制有关。

BACKGROUND：The precise etiopathogenesis of steroid-induced necrosis of femoral head remains unclear.Studies have demonstrated that the differentiation of bone marrow mesenchymal stem cells（BMSCs） was regulated by nervous system in various ways.The regulation mechanism could be affected by steroid to induce osteonecrosis.OBJECTIVE：To observe the changes in neurotransmitter or its receptor mRNA expression in the BMSCs under the steroid condition.METHODS：The rabbit BMSCs were cultivated and isolated by adherence and density gradient centrifugation.The 3rd passage of BMSCs was randomly divided into two groups.In the experimental group,the cells were treated with 10-7 mol/L dexamethasone.In the control group,the cells were normally treated without dexamethasone.The mRNA expressions of nerve growth factor（NGF）,fibroblast growth factor（FGF）,calcitonin gene-related peptide receptor（CGRPR）,vasoactive intestinal peptide receptor（VIPR）,substance P receptor（SPR） and peroxisom proliferator-activeted receptor-γ（PPARγ） of BMSCs were detected on days 4,7,11,15.RESULTS AND CONCLUSION：The expressions of NGF mRNA,FGF mRNA,CGRPR mRNA,VIPR mRNA and SPR mRNA in the experimental group were significantly lower than that in the control group,but the expression of PPARγ mRNA increased significantly（P 0.01）.There were no significantly differences compared among the experimental groups at various time points（P 0.05）.Results suggested that high-dose steriod could depress the expressions of the neurotransmitters or their receptors which could promote the processes of ossification or vascularization in BMSCs.This might be one of the mechanisms for the development of the steroid-induced necrosis of femoral head.