WEHI-345 alleviates sepsis-induced cardiomyopathy by suppressing the RIPK2-mediated MAPK/NF-κB pathway

Sepsis-induced cardiomyopathy (SICM) is a severe complication of sepsis for which effective pharmacological treatment options remain limited. This study aimed to investigate the role of RIPK2, prioritized through cardiac proteomic screening, and evaluate the protective effects of the RIPK2 inhibitor WEHI-345 in SICM.

Quantitative proteomics was performed on cardiac tissues from lipopolysaccharide (LPS)-induced SICM mice, followed by quantitative real-time PCR validation of candidate targets. The effects of WEHI-345 were evaluated in HL-1 cells, neonatal rat ventricular myocytes (NRVMs), and LPS-induced SICM mice. siRNA-mediated Ripk2 knockdown was performed in HL-1 cells for genetic validation. Inflammation, apoptosis, signaling activation, myocardial injury, and cardiac function were assessed by enzyme-linked immunosorbent assay, immunofluorescence, flow cytometry, western blotting, echocardiography, and histological staining.

Proteomic analysis revealed significant enrichment of the nucleotide-binding oligomerization domain-like receptor signaling pathway, with RIPK2 markedly upregulated in LPS-induced SICM. A cytokine mixture plus LPS (Cytomix) increased NOD1/2 expression and activated RIPK2-associated mitogen-activated protein kinase (MAPK)/nuclear factor-κB (NF-κB) signaling. WEHI-345 attenuated Cytomix-induced inflammatory injury and apoptosis in HL-1 cells and NRVMs, suppressed ERK, p38, JNK, and NF-κB activation, and reduced inflammasome-associated responses. These protective effects were partially reproduced by Ripk2 knockdown. In vivo, WEHI-345 improved survival and cardiac function, reduced myocardial injury and inflammation, and suppressed RIPK2/MAPK/NF-κB signaling.

RIPK2 contributes to SICM-associated inflammatory and apoptotic injury, at least partly through MAPK/NF-κB-related signaling. RIPK2 inhibition by WEHI-345 may represent a potential therapeutic strategy for SICM.