Department of Neurology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai 200092, China.
Department of Neurology, Huashan Hospital, Fudan University, Shanghai 20040, China.
Int J Biol Sci. 2024 Jun 11;20(9):3302-3316. doi: 10.7150/ijbs.96116. eCollection 2024.
: Parkinson's disease (PD) is marked by the loss of dopaminergic neurons in the substantia nigra pars compacta, leading to motor and cognitive dysfunctions. The molecular mechanisms underlying synaptic alterations in PD remain elusive, with a focus on the role of Itga5 in synaptic integrity and motor coordination and TAT-Itga5 was designed to suppress PTEN activity in this investigation. : This study utilized MPTP-induced PD animal models to investigate the expression and role of Itga5 in the striatum. Techniques included quantitative PCR, Western blotting, immunostaining, CRISPR-CasRx-mediated knockdown, electrophysiological assays, behavioral tests, and mass spectrometry. : Itga5 expression was significantly reduced in MPTP-induced PD models. In these models, a marked decrease in dendritic spine density and a shift towards thinner spines in striatal GABA neurons were observed, suggesting impaired synaptic integration. Knockdown of Itga5 resulted in reduced dendritic branching, decreased mushroom spines, and increased thin spines, altering synaptic architecture. Electrophysiological analyses revealed changes in action potential and spontaneous excitatory postsynaptic currents, indicating altered synaptic transmission. Motor behavior assessments showed that Itga5 deficiency led to impairments in fine motor control and coordination. Furthermore, Itga5 was found to interact with PTEN, affecting AKT signaling crucial for synaptic development and motor coordination. : The study demonstrates that Itga5 plays a critical role in maintaining synaptic integrity and motor coordination in PD. The Itga5-PTEN-AKT pathway represents a potential therapeutic target for addressing synaptic and motor dysfunctions in PD.
帕金森病(PD)的特征是黑质致密部多巴胺能神经元丧失,导致运动和认知功能障碍。PD 突触改变的分子机制仍不清楚,目前的研究重点是 Itga5 在突触完整性和运动协调中的作用,TAT-Itga5 旨在抑制该研究中 PTEN 的活性。
本研究利用 MPTP 诱导的 PD 动物模型来研究 Itga5 在纹状体中的表达和作用。采用定量 PCR、Western blot、免疫染色、CRISPR-CasRx 介导的敲低、电生理测定、行为测试和质谱等技术。
Itga5 在 MPTP 诱导的 PD 模型中的表达显著降低。在这些模型中,观察到纹状体 GABA 神经元的树突棘密度明显减少,并且向更细的棘转变,提示突触整合受损。Itga5 的敲低导致树突分支减少、蘑菇形棘突减少和细棘突增加,改变了突触结构。电生理分析显示动作电位和自发性兴奋性突触后电流发生变化,表明突触传递发生改变。运动行为评估表明,Itga5 缺乏导致精细运动控制和协调受损。此外,还发现 Itga5 与 PTEN 相互作用,影响 AKT 信号通路,这对突触发育和运动协调至关重要。
该研究表明,Itga5 在 PD 中维持突触完整性和运动协调中发挥着关键作用。Itga5-PTEN-AKT 通路可能成为治疗 PD 中突触和运动功能障碍的潜在靶点。