ALY688 confers cardioprotection through macrophage TGFβ-mediated Treg/Th17 dependent multi-organ responses

Emerging evidence implicates intestinal barrier dysfunction and translocation of microbial factors as key drivers of post-myocardial infarction inflammation and cardiac remodeling, yet therapeutic strategies targeting the gut-heart axis remain underdeveloped. Here we demonstrate that ALY688, an adiponectin receptor agonist peptide, confers robust cardioprotection in rat myocardial ischemia-reperfusion (IR) injury through coordinated immunoregulatory programs in cardiac and intestinal tissues. ALY688 administration during ischemia or at reperfusion and subsequently daily for 28 days significantly preserved cardiac function with improved ejection fraction and fractional shortening, reduced infarct size, and decreased cardiac troponin-I levels. Mechanistic investigation revealed tissue-specific immune reprogramming: in the myocardium, ALY688 directly activated macrophages to secrete TGFβ1, which promoted regulatory T cell (Treg) differentiation from naïve CD4+ T cells as validated in macrophage-T cell co-culture systems. This macrophage-to-Treg axis suppressed inflammasome activation and IL-1β/IL-23/IL-6 signaling while enhancing anti-inflammatory macrophage polarization. Simultaneously, ALY688 strengthened intestinal barrier integrity through activation of the RORγt/IL-17 pathway, upregulating tight junction proteins (Claudin-1, ZO-1) and mucins (MUC19, MUC22), thereby limiting systemic spillover of bacterial endotoxin (LPS) and other microbial metabolites. Multi-omics profiling supported this dual-compartment mechanism: proteomics revealed modulation of immune regulatory (CAPG, CORO1A, MCAM) and cardioprotective (clusterin, NPPA) proteins, while metabolomics demonstrated attenuation by ALY688 of post-IR elevations in pathogenic gut-derived metabolites (anthranilic acid, imidazole propionate, linoleic acid derivatives). This study establishes adiponectin receptor activation as a multi-organ immunometabolic intervention that simultaneously resolves cardiac inflammation while protecting intestinal barrier function. These findings provide mechanistic insight for therapeutic strategies that target the gut-heart axis to address a major remaining unmet clinical need in ischemic heart disease.