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Distinct immunometabolic signatures of type 1 versus type 2 diabetes in a murine model of myocardial infarction

ABSTRACT: Background: Diabetes mellitus (DM), which consists of type I and type 2 diabetes (T1D and T2D), is a known risk factor for myocardial infarction (MI) and negatively impacts post-MI outcomes. However, the mechanisms by which DM exacerbates cardiac remodeling in T1D versus T2D have not been well defined. Here, we assessed acute and chronic post-MI outcomes in T1D and T2D mice, focusing on immune and metabolic pathways. Methods: T1D was induced in adult male mice by a single high dose of streptozotocin (STZ), and T2D induced by high fat/fructose feeding and multiple low STZ doses. Two weeks following STZ administration, MI was induced by permanent coronary artery ligation, and mice were studied at days (D) 3, 7, and 28 post-MI. Cardiac function was assessed by echocardiography. Results: Compared to non-diabetic mice, T1D and T2D mice had worse cardiac dysfunction after MI, including increased wall thinning and decreased ejection fraction, despite similar infarct sizes. T1D mice also displayed acute pulmonary congestion. By RNA-sequencing analysis, T1D and T2D mice displayed upregulation of genes associated with canonical chemokine/monocyte-mediated inflammatory pathways, and downregulation of genes associated with extracellular matrix remodeling. T1D and T2D delayed activation of M2-like (CD206+) macrophages in the heart, and impaired normal collagen and elastin deposition after MI. T2D also increased expression of genes associated with T cell activation, and increased CD8+ T cells in the infarct. T1D and T2D hearts showed signs of impaired glucose and ketone oxidation, and T1D hearts had increased markers of fatty acid oxidation. Extracted D3 cardiac macrophages from T1D and T2D mice exhibited higher basal oxygen consumption, and increased M1 markers and chemokine expression. Plasma from T1D and T2D mice increased chemokine expression (Ccl2, Ccl7, Cxcl1) in cultured bone marrow macrophages, and T2D plasma impaired mitochondrial function. Conclusions: DM promotes adverse cardiac remodeling, which is associated with activation of overlapping and unique inflammatory pathways, impaired ECM remodeling, remote metabolic remodeling, and alterations in macrophage metabolism. Our results provide novel insights into potential therapeutic pathways for DM patients suffering from MI.

ORGANISM(S): Mus musculus

PROVIDER: GSE306097 | GEO | 2025/08/26

REPOSITORIES: GEO

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Project description:Background: Sustained sleep insufficiency impairs immune system and increases the adverse outcomes of cardiovascular diseases. However, the role and mechanisms prolonged sleep fragmentation (SF) on the outcomes of myocardial infarction (MI) remains elusive. Methods: Among 497 MI patients with complete sleep data participating in the National Health and Nutrition Examination Survey, the association between different types of sleep disorders and post-MI survivability was evaluated. We then developed a mouse model with 10 weeks of SF followed by MI surgery. Emergency hematopoiesis and neutrophil expansion were analyzed. Potential mechanisms were explored using bone marrow (BM) transplantation, anti-SiglecF neutralizing antibodies and Interferon alpha and beta receptor subunit 1 knockout (Ifnar1-/-) in BM. Results: Frequent nocturnal awakening independently predicted reduced survival rate of MI patients, with a hazard ratio (HR) of 2.136 (95% CI=1.142-3.995). Increased infarct size, deteriorated cardiac function and lower survival rate were also observed in MI mice pretreated with 10-week SF. SF facilitated post-MI neutrophil expansion and infiltration into infarct area, differentiating into SiglecFhi subset. Inhibition of SiglecFhi neutrophils allowed for the alleviations of post-MI cardiac remodeling. Furthermore, BM progenitors were skewed toward neutrophil lineage concomitant with the clonal expansion of granulocyte-monocyte progenitors (GMPs) in MI mice pretreated with 10-week SF. Transcriptome analysis and functional experiments revealed that activation of type I interferon (IFN) signaling was involved in this process, while depletion of Ifnar1 in BM and administration of IFNAR1-neutralizing antibodies significantly alleviated post-MI cardiac remodeling and neutrophil expansion. Conclusions: SF aggravates post-MI cardiac remodeling and dysfunction through promoting GMP differentiation and neutrophil expansion. Blockage of type I IFN could alleviate this detrimental influence.

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Distinct immunometabolic signatures of type 1 versus type 2 diabetes in a murine model of myocardial infarction

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