Multi-omics Analyses Identify Galectin-1 as a Potential Novel Mediator of Heart Failure with Preserved Ejection Fraction in Mice and Humans

Abstract

Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome where patients present with symptoms of volume overload despite having a normal systolic function. HFpEF is associated with elevation of inflammatory biomarkers, but the precise pathways leading to cardiac dysfunction is not known. In a deoxycorticosterone acetate (DOCA)-salt model of hypertension and HFpEF, we performed CITE-Seq analysis on total leukocytes isolated from the heart, which revealed significant differential gene expression primarily in the myeloid population. We then took the top 20 genes that were differentially expressed between myeloid cells from DOCA-salt vs sham treated mice and performed a genetic analysis called PrediXcan in Vanderbilt’s DNA databank, BioVU. Genetically predicted expression of two genes were associated with a HFpEF phenotype in humans. Of these, the gene encoding galectin 1, Lgals1, had the lowest p-value (0.02) and highest beta coefficient (0.32) corresponding to an odds ratio for HFpEF of 1.38. The role of galectin-1 in heart failure is unknown, we hypothesized that overexpression of Lgals1 exacerbates HFpEF. We found that siRNA knockdown of Lgals1 in bone marrow derived macrophages stimulated with lipoprotein saccharide and IFNγ, they expressed significantly more inflammatory genes such as IL-1α (p<0.0001), IL-6 (p=0.0219), iNOS (p=0.043), and TNFα (p=0.0031) using a 2-way ANOVA followed by Sidak’s multiple comparison test. Next, we explored the role of Lgals1 in the pathophysiology of HFpEF using Lgals1-/- mice. Surprisingly, despite both in vitro and in vivo data supporting a role of galectin-1 in HFpEF, Lgals1-/- mice did not show a significant difference in HFpEF phenotype (blood pressure, exercise tolerance, echocardiography, heart weight, or pulmonary congestion) after DOCA-salt treatment compared to littermate Lgals1+/+ controls in either males or females (p > 0.05 using Student’s t-test for all parameters measured, n=10-12). One hypothesis for this negative result is that Lgals1 is ubiquitously expressed, and a total body knockout may have compensatory mechanisms. We therefore created Lgals1 floxed mice and future studies will determine the effect of macrophage specific deletion of galectin-1 on HFpEF. In conclusion, while multi-omics approaches in mice and humans identify galectin-1 as a novel mediator of HFpEF, further studies in mice are needed to confirm its roles as a potential therapeutic target. 1R01HL161212-01A1, 19EIA34480023,,19IPLOI34760558, and 1T32HL144446-01 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.