Lentiviral Vector-Mediated SHC3 Silencing Exacerbates Oxidative Stress Injury in Nigral Dopamine Neurons by Regulating the PI3K-AKT-FoxO Signaling Pathway in Rats with Parkinson’s Disease

Parkinson's disease (PD) is a prevalent disease that leads to motor and cognitive disabilities, and oxidative stress (OS) injury was found to be related to the etiology of PD. Increasing evidence has shown that SHC3 is aberrantly expressed in neurons. The current study examines the involvement of SHC3 silencing in OS injury in the nigral dopamine neurons in rats with PD via the PI3K-AKT-FoxO signaling pathway. To study the mechanisms and functions of SHC3 silencing in PD at the tissue level, 170 rats were selected, and a lentivirus-based packaging system was designed to silence SHC3 expression in rats. Furthermore, PC12 cells were selected for in vitro experimentation. To evaluate the effect of SHC3 silencing in nigral dopamine neuronal growth, an MTT assay, propidium iodide (PI) single staining and Annexin V-PI double staining were performed to detect cell viability, cell cycle progression and cell apoptosis, respectively. SHC3 shRNA led to decreased SOD and MDA levels and enhanced GSH activity, indicating that SHC3 silencing leads to motor retardation. SHC3 silencing repressed the extent of Akt and FoxO phosphorylation, thereby inhibiting the PI3K-AKT-FoxO signaling pathway. Furthermore, in cell experiments, SHC3 silencing suppressed PC12 cell proliferation and cell cycle progression, whereas it enhanced cell apoptosis. The current study provides evidence suggesting that SHC3 silencing may aggravate OS injury in nigral dopamine neurons via downregulation of the PI3K-AKT-FoxO signaling pathway in PD rats.