Enhanced Production of Lipid Mediators in Plasma and Activation of DNA Damage Pathways in PBMCs Are Correlated With the Severity of Ancestral SARS-CoV-2 Infection

Many questions remain unanswered regarding the implication of genetics and lipid metabolites with severe SARS-CoV-2 infections. We performed bulk RNA-seq and a total fatty acid panel analysis on PBMCs and plasma collected from 10 infected and 10 uninfected patients. Univariate comparison of lipid metabolites using the Mann–Whitney U-test revealed that six lipid metabolites were significantly increased in COVID-19 patients, including the lipid mediators arachidonic acid (AA) and eicosapentaenoic acid (EPA), which both give rise to eicosanoids. Key lipids implicated in inflammation, including AA and EPA, along with the fatty acids DHA and DPA, were significantly and positively correlated to the WHO disease severity score. Analysis of our bulk RNA-seq dataset demonstrated distinct transcriptional profiles leading to a segregation of COVID-19 patients based on the WHO score. Ontology, KEGG, and Reactome analysis identified several key pathways and nodes that were enriched for genes related to innate immunity, interactions between lymphoid and nonlymphoid cells, interleukin signaling, and subsequent DNA damage pathways.

EPA levels correlated with heightened cell cycling and DNA damage pathways observed in patients with a high WHO score. We studied gene expression in nasopharyngeal swabs from 58 healthy and COVID-19 participants and identified that genes implicated in eicosanoid synthesis, such as alox5, alox12, and alox15B, were specifically up-regulated in high WHO score patients in several cell types of the nasopharynx, especially goblet cells across different viral variants (Deta and Omicron). Using published nasal scRNA-seq datasets from COVID-19 patients, we evaluated the expression of genes implicated in eicosanoid synthesis, such as ALOX5, ALOX15, and ALOX15B, across nasal cell types and COVID-19 severity groups. Altogether, our study highlights the fact that the increase in specific lipids implicated in inflammation and the genes required for their synthesis correlated with the severity of the SARS-CoV-2 infection.