Protective effect of astragaloside IV against zinc oxide nanoparticles induced human neuroblastoma SH-SY5Y cell death: a focus on mitochondrial quality control.

Occupational and unintentional exposure of zinc oxide nanoparticles (ZnONPs) raises concerns regarding their neurotoxic potential and there is an urgent need for the development of effective agents to protect against the toxic effects of ZnONPs. Astragalus memeranaceus (AM), a famous Traditional Chinese Medicine, as well as its bioactive components, showing a potential neuroprotective function. This study aims to investigate the neuroprotective effects of bioactive components of AM against ZnONPs-induced toxicity in human neuroblastoma SH-SY5Y cells and its underlying mechanisms. The cell apoptosis, ROS generation, MMP changes, mitochondrial fission/fusion, biogenesis, and mitophagy were assessed. In this study, AM treatment inhibited ZnONPs-induced cell apoptosis and ROS overproduction in SH-SY5Y cells. And astragaloside IV (ASIV) played a dominant role in the attenuation of cytotoxicity after ZnONPs exposure, rather than flavonoids and polysaccharides. ASIV treatment significantly reduced ROS generation and MMP collapse in ZnONPs-exposed cells. Furthermore, the protein expressions of mitochondrial biogenesis (PGC-1α), fusion (Mfn1 and Mfn2), and fission (Drp1) were markedly increased. Meanwhile, the PINK1/Parkin-mediated mitophagy was activated after ASIV administration, which ameliorated ZnONPs-induced SH-SY5Y cell death. Collectively, ASIV administration mitigated ZnONPs-induced cytotoxicity in SH-SY5Y cells through restoring mitochondrial quality control process, which hinted the protective role of ASIV in ZnONPs-induced neurotoxicity.