Zika Virus Induces Tumor Necrosis Factor-Related Apoptosis Inducing Ligand (TRAIL)-Mediated Apoptosis in Human Neural Progenitor Cells

Abstract

Zika virus (ZIKV) remains as a public health threat due to the congenital birth defects the virus causes following infection of pregnant women. Congenital microcephaly is among the neurodevelopmental disorders the virus can cause in newborns, and this defect has been associated with ZIKV-mediated cytopathic effects in human neural progenitor cells (hNPCs). In this study, we investigated the cellular changes that occur in hNPCs in response to ZIKV (African and Asian lineages)-induced cytopathic effects. Transmission electron microscopy showed the progress of cell death as well as the formation of numerous vacuoles in the cytoplasm of ZIKV-infected hNPCs. Infection with both African and Asian lineages of ZIKV induced apoptosis, as demonstrated by the increased activation of caspase 3/7, 8, and 9. Increased levels of proinflammatory cytokines and chemokines (IL-6, IL-8, IL-1β) were also detected in ZIKV-infected hNPCs, while z-VAD-fmk-induced inhibition of cell death suppressed ZIKV-mediated cytokine production in a dose-dependent manner. ZIKV-infected hNPCs also displayed significantly elevated gene expression levels of the pro-apoptotic Bcl2-mediated family, in particular, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Furthermore, TRAIL signaling led to augmented ZIKV-mediated cell death and the knockdown of TRAIL-mediated signaling adaptor, FADD, resulted in enhanced ZIKV replication. In conclusion, our findings provide cellular insights into the cytopathic effects induced by ZIKV infection of hNPCs.

The Dual Regulation of Apoptosis by Flavivirus

“…And numerous reports show that neural cell apoptosis increases after ZIKV infection ( Huang W.-C. et al, 2016 ; Li et al, 2016 ; Qian et al, 2016 ; Souza et al, 2016 ; Ghouzzi et al, 2017 ). For example, ZIKV preferentially induces apoptosis of neuro progenitor cells (NPCs), which is confirmed by the activation of caspases-3/7, -8, and -9 and the significantly elevated gene expression of TRAIL, as well as ultrastructural and flow cytometry analysis ( Tang et al, 2016 ; Jungmann et al, 2017 ; Lee et al, 2020 ). In human neural stem cells (hNSCs), the cleavage of PARP and caspase-3 are participated in the apoptosis process ( Devhare et al, 2017 ).…”

Nonstructural Protein NS1 of Influenza Virus Disrupts Mitochondrial Dynamics and Enhances Mitophagy via ULK1 and BNIP3

“…β-actin was used as an internal reference for normalizing the gene expression quantified by real-time PCR. The primer sequences are listed in the Table 1 [ 29 ].…”

“…The mitochondrial fractions were isolated using the Mitochondria Isolation Kit for Cultured Cells (Abcam) according to manufacturer’s instruction. Immunoblot analysis was performed as described previously [ 29 , 30 ]. Cells were lysed with RIPA buffer (Sigma-Aldrich) mixed with a protease and phosphatase inhibitor cocktail (Roche) at the specified time points.…”

CVB3-Mediated Mitophagy Plays an Important Role in Viral Replication via Abrogation of Interferon Pathways

“…Mock-or CVB3-infected hNPCs were washed, pelleted and prepared for TEM analysis as described previously ( Lee et al., 2020 ). After fixing the cells with PBS containing 2.5% glutaraldehyde and 2% paraformaldehyde for 30 min at 4°C, cells were post-fixed in 1% osmium tetroxide in PBS and differential concentrations of ethanol gradient (30%, 50%, 70%, 85%, and 95%) and 100% acetone were used to dehydrate the cells.…”