丙烯醛在颅脑爆炸创伤诱导的帕金森病中的作用机制研究

Study on the mechanism of acrolein on Parkinson's disease caused by brain blast injury

目的探索丙烯醛(Acrolein,ACR)在爆炸颅脑创伤(Bomb traumatic brain injury,bTBI)诱导的帕金森病(Parkinson's disease,PD)中的作用机制。方法选取健康雄性SD大鼠24只,随机分为正常对照组(sham组8只)和bTBI组(2 d组8只和7 d组8只)。收集sham组和损伤后(1、2、3、5、7 d)大鼠尿液评估ACR代谢产物N-乙酰基-S-(3-羟基丙基)半胱氨酸(3-HPMA)变化。大鼠安乐死后取一侧大脑通过Western blot评估全脑、纹状体(Striatum,STR)前后区和黑质区(Substantia nigra,SN)的ACR、α突触核蛋白(a-synuclein,a-syn)、磷酸化与未磷酸化酪氨酸羟化酶(Tyrosine hydroxylase,TH)水平变化,并通过免疫荧光法在另一侧脑半球检测α-syn与ACR的荧光共定位。结果与sham组相比,3-HPMA在损伤后开始明显增加(P<0.05);与sham相比,2 d和7 d组全脑、STR前区、STR后区和SN区中的ACR均显著增加(P<0.05);与sham相比2 d和7 d组全脑、STR前区、STR后区和SN区25 kDa的α-syn均显著增加(P<0.05),但除SN区19 kDa的α-syn增加外,其余各部位均显著降低(P<0.05),而且除SN区7 d组之外各部位25 kDa/19 kDaα-syn的比值在2、7 d均显著增加(P<0.05);与sham组相比,SN区unp-TH水平升高,pTH-Ser31水平降低(P<0.05),全脑和SN区的丝氨酸40位磷酸化酪氨酸羟化酶(pTH-Ser40)均降低,而在STR前、后区均升高(P<0.05);与sham组相比,2、7 d组STR和SN中α-syn蛋白和ACR的共定位增加。结论ACR可以作为TBI介导PD的病理过程中的关键分子,填补了TBI后PD发病机制的空白,为治疗TBI后PD开辟了新的途径。

Objective To explore the mechanism of Acrolein(ACR)on bomb traumatic brain injury(bTBI)-induced Parkinson's disease(PD).Methods Twenty-four healthy male SD rats were selected and randomly divided into sham group(n=8)and bTBI group(8 rats in 2 d group and 8 rats in 7 d group).Changes of ACR metabolites,such as N-acetyl-S-(3-hydroxypropyl)cysteine(3-HPMA),were assessed in urine of sham group 1,2,3,5 and 7 days after injury,respectively.One side of rat brain was collected to evaluate the brain,brain striatum(STR)and substantia nigra(SN)of ACR,α-synuclein(α-syn),phosphorylated and non-phosphorylated tyrosine hydroxylase(TH)changes by Western blot assay and the other side of brain was used to assess the colocalization ofα-syn and TCR by immunofluorescence staining.Results Compared with sham group,3-HPMA began to increase after injury.Compared with sham group,TCR in brain,anterior STR,posterior STR and SN regions were increased in 2 d and 7 d bTBI groups.Compared with sham group,α-syn in brain,STR region,STR region and SN region were increased.However,except for the increase ofα-syn in SN,the ratio of 25 kDa/19 kDaα-syn in SN was decreased,and the ratio of 25 kDa/19 kDaα-syn in SN region of bTBI group was increased.Compared with sham group,the level of unp-TH in SN region was increased and the level of pTH-Ser31 was decreased.The phosphorylated TH at Serine 40 in brain and SN region(p-ser40)was decreased,while the level of STR in the anterior and posterior regions was increased.Compared with sham group,colocalization ofα-syn and TCR in STR and SN of bTBI group was increased.Conclusion ACR could be used as a key molecule in the pathological process of TBI-mediated PD,which fills the gap in the pathogenesis of PD after TBI,and opens up a new way for the treatment of PD after TBI.