PTX3 exacerbates hepatocyte pyroptosis in hepatic ischemia-reperfusion injury by promoting macrophage M1 polarization

Backgrounds: Hepatic ischemia-reperfusion injury (IRI) triggers macrophage activation, which in turn mediates inflammatory responses and affects tissue repair and injury severity. Pentraxin 3 (PTX3) is vital in immune regulation and inflammatory processes. In this study, we aim to investigate the potential role of PTX3 in macrophage-mediated hepatic IRI.

Methods: Gene expression profiles and single-cell data were obtained from the Gene Expression Omnibus (GEO) database. Immunohistochemistry was used to evaluate the expression levels of PTX3, CD68, and CD86 in samples from the human and mouse hepatic IRI models. The effects of PTX3 knockdown or overexpression on macrophage polarization were assessed in Raw264.7. PTX3 knockdown/ overexpression in Raw264.7 and co-culturing with AML12 were performed under conditions of hypoxia-reoxygenation (H/R) to examine pyroptosis and injury in AML12.

Results: PTX3 expression was significantly upregulated in both human and mouse hepatic IRI model samples. Bulk and single-cell RNA-seq data analyses revealed that PTX3 is associated with inflammatory response pathways and macrophage activation. Macrophages with high PTX3 expression exhibit M1-like characteristics. Similarly, overexpression of PTX3 promotes M1 polarization of Raw264.7 after H/R, while the knockdown group exhibits reduced M1 polarization. Co-culture results indicated that pyroptosis in AML12 was significantly reduced after H/R in the PTX3 knockdown group, whereas the PTX3 overexpression group exhibited the opposite outcome.

Conclusion: PTX3 regulates macrophage polarization during hepatic IRI, consequently influencing hepatocellular pyroptosis.