Cholesterol 25‐Hydroxylase inhibits SARS ‐CoV‐2 and other coronaviruses by depleting membrane cholesterol

Abstract

Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2 and has spread across the globe. SARS-CoV-2 is a highly infectious virus with no vaccine or antiviral therapy available to control the pandemic; therefore, it is crucial to understand the mechanisms of viral pathogenesis and the host immune responses to SARS-CoV-2. SARS-CoV-2 is a new member of the betacoronavirus genus like other closely related viruses including SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). Both SARS-CoV and MERS-CoV have caused serious outbreaks and epidemics in the past eighteen years. Here, we report that one of the interferon-stimulated genes (ISGs), cholesterol 25-hydroxylase (CH25H), is induced by SARS-CoV-2 infection in vitro and in COVID-19-infected patients. CH25H converts cholesterol to 25-hydrocholesterol (25HC) and 25HC shows broad anti-coronavirus activity by blocking membrane fusion. Furthermore, 25HC inhibits USA-WA1/2020 SARS-CoV-2 infection in lung epithelial cells and viral entry in human lung organoids. Mechanistically, 25HC inhibits viral membrane fusion by activating the ER-localized acyl-CoA:cholesterol acyltransferase (ACAT) which leads to the depletion of accessible cholesterol from the plasma membrane. Altogether, our results shed light on a potentially broad antiviral mechanism by 25HC through depleting accessible cholesterol on the plasma membrane to suppress virus-cell fusion. Since 25HC is a natural product with no known toxicity at effective concentrations, it provides a potential therapeutic candidate for COVID-19 and emerging viral diseases in the future.

SARS-CoV-2 Requires Cholesterol for Viral Entry and Pathological Syncytia Formation

“…Apilimod, a PIKFYVE inhibitor and promising therapeutic in multiple SARS-CoV-2 models (Kang et al, 2020;Riva et al, 2020) including heterokaryon assays tested herein ( Figures 3E; S3B), prevented pseudoparticle entry at nanomolar concentrations ( Figure 7B). By contrast, 25-hydroxycholesterol, which lowers plasma membrane cholesterol by redirection to the cell interior (Abrams et al, 2020;Im et al, 2005;Wang et al, 2020;Yuan et al, 2020;Zhu et al, 2020b;Zu et al, 2020), had no effect ( Figure 7C). However, MBCD, which directly "strips" plasma membrane cholesterol without engaging intracellular targets (Zidovetzki and Levitan, 2007), blocked virus entry ( Figure 7D).…”

Diabetes, obesity, metabolism, and SARS-CoV-2 infection: the end of the beginning

“…Cholesterol-binding domains within the SARS-CoV-2 spike protein interact with HDL, indirectly facilitating viral entry through the SR-B1 cell surface receptor in an ACE2-dependent manner ( Wei et al., 2020 ) ( Figure 1 ). Cholesterol 25-hydroxylase (CH25H), a known interferon-stimulated gene, enables the synthesis of the oxysterol 25-hydroxy cholesterol (25HC) from cholesterol; notably, 25HC exhibits broad antiviral activity and inhibits intracellular entry of MERS-CoV and SARS-CoV-2 via selective depletion of plasma membrane, but not total cell cholesterol ( Wang et al., 2020c ). CH25H expression was upregulated in cells following SARS-CoV-2 infection ex vivo , and levels of CH25H were increased in macrophages and epithelial cells from bronchioalveloar lavage (BAL) fluid obtained from individuals hospitalized with SARS-CoV-2 infection ( Wang et al., 2020c ).…”

Insights to SARS-CoV-2 life cycle, pathophysiology, and rationalized treatments that target COVID-19 clinical complications

“…Additionally, the small molecule SSAA09E3 was found to suppress the fusion of the host cellular membrane with the virus membrane in a SARS-CoV-1 infection model [ 85 ]. Other fusion inhibitors that can be considered include 25-hydrocholesterol which showed broad anti-coronavirus activity by blocking membrane fusion and inhibiting SARS-CoV-2 infection in lung epithelial cells and viral entry in human lung organoids [ 93 ].…”