Ergosterol Peroxide Inhibits Porcine Epidemic Diarrhea Virus Infection in Vero Cells by Suppressing ROS Generation and p53 Activation

Abstract

Porcine epidemic diarrhea virus (PEDV) is an alphacoronavirus that causes severe watery diarrhea in piglets with high morbidity and mortality, resulting in serious economic losses to the farming industry. Ergosterol peroxide (EP) is a sterol with diverse biological activities including antiviral activity. In this study, we explored whether EP extracted from the fruiting body of the mushroom Cryptoporus volvatus had the potential to inhibit PEDV infection in Vero cells. The results revealed that EP had a remarkable inhibitory effect on PEDV infection. It could significantly inhibit multiple stages of the PEDV life cycle, including internalization, replication and release, and could directly inactivate PDCoV infectivity. However, it did not affect PEDV attachment. Furthermore, EP alleviated PEDV-induced apoptosis and mitigated the decrease in mitochondrial membrane potential caused by PEDV infection. It suppressed ROS generation and p53 activation caused by PEDV infection. The ROS scavenger N-acetyl-l-cysteine (NAC) and the p53 specific inhibitor Pifithrin-α (PFT-α) suppressed PEDV-induced apoptosis and impeded viral replication, suggesting that ROS and p53 play an important role in PEDV-induced apoptosis and viral replication. Collectively, EP can prevent PEDV internalization, replication and release, possesses the ability to directly inactivate PEDV, and can inhibit PEDV-induced apoptosis by interfering with PEDV-induced ROS production and p53 activation. These findings highlight the therapeutic potential of EP against PEDV infection.

In silico and in vitro evaluation of antiviral activity of wogonin against main protease of porcine epidemic diarrhea virus

“…It was reported that a boiled extract of wogonin enables the interception of viral activity ( Li-Weber, 2009 ). Wogonin might interpose the virus–cell membrane fusion of PEDV through spike protein (S), inhibiting viral internalization ( Liu et al., 2022 ). Additionally, the effect on PEDV release may also be mediated by the modulation of innate immune responses ( Ma et al., 2002 ).…”

“…To examine the effect of wogonin on PEDV inactivation, PEDV (MOI = 0.05) and wogonin (50 μM) were incubated together at 37°C for 2 h. Then, the mixture was washed with PBS and ultracentrifuged at 90,000 × g for 1.5 h at 4°C in 20% sucrose buffer (w/w) to purify the virions. Subsequently, the virions were resuspended in the culture medium, and the cell lysates were harvested for RT-qPCR ( Liu et al., 2022 ).…”

“…For instance, puerarin ( Zhang et al., 2021 ; Ren et al., 2022 ) has been reported to inhibit PEDV replication and pro-inflammatory response, alleviating intestinal injury and modulating intestinal microorganisms in PEDV-challenged piglets ( Wu et al., 2020 ; Wu et al., 2021 ), while glycyrrhizin has been noted to inhibit PEDV infection and decrease pro-inflammatory cytokine secretion via the HMGB1/TLR4-mitogen-activated protein kinase (MAPK) p38 pathway ( Gao et al., 2020 ). Furthermore, monolaurin has been observed to exert a protective effect against PEDV infection in piglets by regulating the interferon pathway ( Zhang et al., 2021 ); cinchonine has been found to suppress PEDV infection by inducing autophagy in the early stage of PEDV replication ( Ren et al., 2022 ); and ergosterol peroxide has been reported to restrain multiple stages of the PEDV life cycle by suppressing ROS generation and the p53 signaling pathway ( Liu et al., 2022 ). Although quercetin 7-rhamnoside did not directly interact with or inactivate PEDV particles, it affected the initial stage of PEDV infection by disturbing PEDV replication ( Choi et al., 2009 ).…”

A Review of Bioactive Compounds against Porcine Enteric Coronaviruses

“…PEDV triggers caspase-independent apoptosis through the activation of the mitochondrial apoptosis-inducing factor (AIF) and induces caspase-8- and caspase-3-mediated apoptosis in the late stages of infection [ 7 , 8 ]. The reactive oxygen species (ROS)-p53 pathway participates in PEDV-induced apoptosis [ 11 ]. PDCoV causes caspase-dependent intrinsic apoptosis by triggering the release of the mitochondrial cytochrome c into the cytoplasm [ 9 ].…”

“…Ergosterol peroxide restricts PEDV internalization, replication and release. In addition, it has the ability to inactivate PEDV virions and alleviate PEDV-induced apoptosis [ 11 ]. The aqueous leaf extract of the Moringa oleifera tree is able to suppress PEDV-induced oxidative stress (e.g., reduce ROS and malondialdehyde (MDA) production and restore glutathione peroxidase (GSH-Px) activity) and inhibit apoptosis.…”