MPTP小鼠脑沉默信息调节因子1和缺氧诱导因子-1α的表达及行为学检测

Expression of silent information regulator 1 and hypoxia-inducible factor 1α and behavioral changes in MPTP mice

目的本研究旨在研究MPTP模型小鼠中沉默信息调节因子1(SIRT1)和缺氧诱导因子1α(HIF-1α)的表达情况以及行为学的变化。方法选用MPTP处理C57BL/6小鼠构建PD动物模型,采用行为学实验、高效液相色谱(HPLC)、免疫组化等方法检验模型的建立是否成功,并在小鼠模型中检测SIRT1和HIF-1α的表达情况。结果 MPTP处理的小鼠表现出显著的行为学异常,主要体现在自主活动减少(P<0.001)、步距缩短(P<0.001),且有显著运动迟缓(P<0.001)。HPLC结果发现,模型组小鼠纹状体区域多巴胺(DA)及其代谢产物减少(P<0.001)。免疫组化结果提示黑质区域多巴胺能神经元标志物酪氨酸羟化酶(TH)和多巴胺转运体(DAT)的表达明显下调(P<0.01)。分子生物学方面,PD模型小鼠的SIRT1表达降低(P<0.05),HIF-1α表达增加(P<0.05)。结论 PD模型小鼠表现出明显的行为学异常,多巴胺能神经元标志物检测提示成功复制PD动物模型,同时发现模型小鼠的SIRT1/HIF-1α的表达异常,提示该信号通路可能参与了PD的疾病过程。

Objective To investigate the expression of silent information regulator 1（ SIRT1） and hypoxia-inducible factor 1α（ HIF-1α） and behavioral changes in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine（ MPTP） mice. Methods C57BL/6 mice were treated with MPTP to establish a Parkinson＇s disease（ PD） model. The successful establishment of PD model was confirmed by behavioral test,high-performance liquid chromatography（ HPLC）,and immunohistochemistry. The expression of SIRT1 and HIF-1α in PD model mice was determined by Western blot. Results The mice treated with MPTP showed significant behavioral abnormalities： reduced autonomic activity,shortened step length,and bradykinesia（ all P〈0. 001）. The HPLC results showed that the PD model mice had significantly lower levels of dopamine and its metabolites in the striatum than the control mice（ P〈0. 001）. The immunohistochemistry results showed that the levels of tyrosine hydroxylase and dopamine transporter（ dopaminergic neuron markers） in the substantia nigra of PD model mice were significantly down-regulated（ P〈0. 01）. The PD model mice had a significantly lower level of SIRT1 and a significantly higher level of HIF-1α compared with the control mice（ P〈0. 05）. Conclusions The PD model mice have significant behavioral abnormalities. The decrease in levels of dopaminergic neuron markers suggests that the PD model is successfully established. The abnormal expression of SIRT1/HIF-1α in the PD model mice indicates that the SIRT1/HIF-1 signaling pathway may be involved in the development of PD.