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MYC-mediated early glycolysis negatively regulates proinflammatory responses by controlling IRF4 in inflammatory macrophages

ABSTRACT: MYC activates different metabolic programs in a cell-type and cell-status dependent manner. However, the role of MYC in inflammatory macrophages has not yet been determined. Metabolic and molecular analyses reveal that MYC, but not HIF1, is involved in enhancing early glycolytic flux during inflammatory macrophage polarization. Ablation of MYC decreases lactate production by regulating lactate dehydrogenase (LDH) activity and causes increased inflammatory cytokines by regulating interferon regulatory factor 4 (IRF4) in response to lipopolysaccharide (LPS). Moreover, myeloid-specific deletion of MYC and pharmacological inhibition of MYC/LDH axis enhance inflammation and the bacterial clearance in vivo. These results elucidate the potential role of the MYC/LDH/IRF4 axis in inflammatory macrophages by connecting early glycolysis and inflammatory responses and suggest that modulating early glycolytic flux mediated by the MYC/LDH axis can be utilized to open new avenues for the therapeutic modulation of macrophage polarization to fight against bacterial infection.

ORGANISM(S): Mus musculus

PROVIDER: GSE164475 | GEO | 2021/07/14

REPOSITORIES: GEO

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MYC-mediated early glycolysis negatively regulates proinflammatory responses by controlling IRF4 in inflammatory macrophages

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