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Gupte, S. A.

Publications and source records attributed to Gupte, S. A..

2 recordsLinked to original sources

12-Lipoxygenase (12-LOX) Plays a Key Role in Hyperinflammatory Response Caused by SARS-CoV-2

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has led to significant global morbidity and mortality. The severe disease outcomes are often linked to a hyperinflammatory response known as a "cytokine storm." The underlying mechanisms responsible for this exaggerated immune response remain incompletely understood. This study aimed to investigate the molecular pathways contributing to the severe inflammatory damage and mortality associated with COVID-19. SARS-CoV-2 hijacks host lipid metabolism, particularly the phospholipase A2 (PLA2) pathway, which leads to the production of the bioactive molecules, including the 12-Lipoxygenase (12-LOX)-derived lipid mediators in platelets, as well as in lung and vascular cells. We hypothesized that 12-LOX drives the hyperinflammatory response and disease severity, and that its inhibition could reduce inflammation and improve outcomes. Analysis of autopsy lung samples from COVID-19 decedents and SARS-CoV-2-infected K18-hACE2 transgenic mice revealed increased 12-LOX expression. We evaluated VLX-1005, a selective small-molecule 12-LOX inhibitor, in infected mice. Treatment initiated 48 hours post-infection significantly improved survival, reduced body weight loss, and decreased lung inflammation compared to controls. Notably, male mice showed higher survival rates than females. VLX-1005 treatment also suppressed key chemokines and cytokines associated with the cytokine storm, and reduced lung damage. These findings identify 12-LOX as a critical mediator of the hyperinflammatory response in severe COVID-19 and support its inhibition as a promising therapeutic strategy to mitigate inflammatory damage and reduce mortality. SignificanceThis study provides critical insights into the mechanisms underlying severe COVID-19, identifying 12-Lipoxygenase (12-LOX) as a key driver of the hyperinflammatory response that contributes to disease severity and mortality. By demonstrating that SARS-CoV-2 hijacks host lipid metabolism to elevate pro-inflammatory lipid mediators, the research uncovers a novel pathogenic pathway that exacerbates lung inflammation. The use of VLX-1005, a selective 12-LOX inhibitor, significantly improved survival and reduced inflammatory damage in a mouse model, highlighting its therapeutic potential. These findings not only deepen our understanding of COVID-19 pathogenesis but also position 12-LOX as a promising target for intervention, offering a new avenue for mitigating the effects of cytokine storms in severe cases.

microbiology↗

Studies in CRISPR-generated Mediterranean G6PD variant rats reveal G6PD orchestrates genome-wide DNA methylation and gene expression in vascular wall

BackgroundRecent advances have revealed the importance of epigenetic modifications to gene regulation and transcriptional activity. DNA methylation, a determinant of genetic imprinting and de novo silencing of genes genome-wide, is known to be controlled by DNA methyltransferases (DNMT) and demethylases (TET) under disease conditions. However, the mechanism(s)/factor(s) influencing the expression and activity of DNMTs and TETs, and thus DNA methylation, in healthy vascular tissue is incompletely understood. Based on our recent studies, we hypothesized that glucose-6-phosphate dehydrogenase (G6PD) is a modifier of DNMT and TET expression and activity and an enabler of gene expression. MethodsIn aorta of CRISPR-edited rats with the Mediterranean G6PD variant we determined DNA methylation by whole-genome bisulfite sequencing, gene expression by RNA sequencing, and large artery stiffness by echocardiography. ResultsHere, we documented higher expression of Dnmt3a, Tet2, and Tet3 in aortas from Mediterranean G6PDS188F variant (a loss-of-function single nucleotide polymorphism) rats than their wild-type littermates. Concomitantly, we identified 17,618 differentially methylated loci genome-wide (5,787 hypermethylated loci, including down-regulated genes encoding inflammation- and vasoconstriction-causing proteins, and 11,827 hypomethylated loci, including up-regulated genes encoding smooth muscle cell differentiation- and fatty acid metabolism-promoting proteins) in aorta from G6PDS188F as compared to wild-type rats. Further, we observed less large artery (aorta) stiffness in G6PDS188F as compared to wild-type rats. ConclusionsThese results establish a noncanonical function of the wild-type G6PD and G6PDS188F variant in the regulation of DNA methylation and gene expression in healthy vascular tissue and reveals G6PDS188F variant contributes to reduce large artery stiffness. HighlightsO_LIThe wild-type G6PD and G6PDS188F variant regulates the expression and activity of nuclear DNMT and TET and selectively evokes hyper/hypo-methylation of loci/promoter regions genome-wide. C_LIO_LIG6PDS188F variant represses and activates genes detrimental and beneficial to vascular cell phenotype and function, respectively. C_LIO_LIG6PDS188F variant reduces large artery stiffness. C_LI

biochemistry↗