Maresin 1 modulates renal and cardiac lipid profiles in hypertensive rats

Chronic inflammation contributes significantly to hypertension and associated target organ damage, particularly in the heart and kidneys. Specialized proresolving mediators, a class of bioactive lipids, play key roles in resolving inflammation and maintaining tissue homeostasis. Among them, Maresin 1 (MaR1) has been implicated in cardiovascular regulation and blood pressure control. We hypothesized that MaR1 may mitigate salt-induced hypertension and its related effects in Dahl salt-sensitive (SS) rats. In this study, SS rats were fed a high-salt diet and treated with MaR1. Mean arterial pressure (MAP) and heart rate (HR) were continuously monitored. Echocardiography and histology were used to assess cardiac structure, contractility, and fibrosis. Lipidomic profiling quantified inflammation-resolving lipid mediators, and transcriptomic analysis identified organ-specific gene expression changes. MaR1 treatment did not significantly alter MAP, HR, or cardiac structure and function. Echocardiographic and histological evaluations showed no significant changes in cardiac remodeling, contractility, or collagen deposition in the heart or kidney. However, lipidomic profiling revealed shifts in inflammatory lipid mediators, suggesting immunomodulatory and metabolic effects of MaR1. Transcriptomic analysis demonstrated organ-specific gene expression changes, with upregulation of circadian pathways in the heart and modulation of immune signaling in the kidney. Notably, MaR1 influenced circadian blood pressure rhythms, enhancing amplitude and shifting the acrophase, consistent with altered expression of circadian clock genes. Although MaR1 did not affect hypertension development directly, its modulation of lipid metabolism, inflammatory pathways, and circadian regulation suggests therapeutic potential. Future studies should assess longer treatments and combination approaches to clarify its role in cardiorenal disease management.<b>NEW & NOTEWORTHY</b> This study shows that MaR1, a specialized proresolving mediator, influences lipid metabolism and modifies gene expression in the heart and kidney in a salt-sensitive hypertension model, without affecting blood pressure or organ structure. These findings highlight the potential role of MaR1 in regulating inflammation and circadian rhythms associated with cardiovascular and renal diseases.