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Background: Alcohol‐associated cardiomyopathy (ACM) is a cardiac muscle disease characterized by inflammation and oxidative stress. Thromboxane‐prostanoid receptor (TP‐R) plays an important role in the pathogenesis of cardiovascular disease. Herein, we hypothesize that TP‐R mediates alcohol‐induced early cardiac injury. Methods: Eight‐week‐old male C57BL/6 wild‐type mice were fed a chronic ethanol (ET) or control diet (CON) for 10 days followed by a single binge of ethanol or maltose‐dextrin through oral gavage. A cohort of ethanol‐fed mice received SQ 29,548 (SQ), a TP‐R antagonist. RNA sequencing, real‐time PCR, and western blot analysis were performed on left ventricle to investigate alterations in genes and/or proteins mediating oxidative stress, inflammation, and cardiac remodeling. Sirius Red staining was performed to measure myocardial fibrosis. Results: RNA‐sequencing analysis of myocardium from CON and ET groups identified 142 genes that were significantly altered between the two groups. In particular, the gene expression of thioredoxin‐interacting protein (TXNIP), a component of NLR family pyrin domain containing 3 (NLRP3) signaling, which mediates oxidative stress and inflammatory response, was upregulated in response to ethanol exposure. The myocardial protein levels of TP‐R and thromboxane A2 synthase were increased upon alcohol exposure. Ethanol increased the levels of 4‐hydroxynonenal, a marker of oxidative stress, with a concomitant increase in the protein levels of TXNIP and NLRP3, and administration of SQ attenuated these effects. Additionally, ethanol increased the protein levels of pro‐inflammatory mediators, including tumor necrosis factor alpha and the NLRP3 downstream product, secretory interleukin 1 beta, and SQ blunted these effects. Finally, the Sirius red staining of the myocardium revealed an increase in collagen deposition in ethanol‐fed mice which was attenuated by TP‐R antagonism. Conclusion: This study demonstrates that ethanol promotes the NLRP3 signaling pathway within the myocardium, leading to a pro‐inflammatory milieu that potentially initiates early myocardial remodeling, and TP‐R antagonism attenuates this effect. [ABSTRACT FROM AUTHOR]

Saturated fatty acids (SFAs) are considered to be detrimental to human health. One of the SFAs, myristic acid (MA), is known to exert a hypercholesterolemic effect in mice as well as humans. However, its effects on altering adipose tissue (AT) inflammation and systemic insulin resistance (IR) in obesity are still unclear. Here, we sought to determine the effects of a high fat (HF) diet supplemented with MA on obesity-associated metabolic disorders in mice. Wild-type C57BL/6 mice were fed a HF diet in the presence or absence of 3% MA for 12 weeks. Plasma lipids, plasma adipokines, AT inflammation, systemic IR, glucose homeostasis, and hepatic steatosis were assessed. The body weight and visceral adipose tissue (VAT) mass were significantly higher in mice receiving the HF+MA diet compared to HF diet-fed controls. Plasma total cholesterol levels were marginally increased in HF+MA-fed mice compared to controls. Fasting blood glucose was comparable between HF and HF+MA-fed mice. Interestingly, the plasma insulin and HOMA-IR index, a measure of insulin resistance, were significantly higher in HF+MA-fed mice compared to HF controls. Macrophage and inflammatory markers were significantly elevated in the AT and AT-derived stromal vascular cells upon MA feeding. Moreover, the level of circulating resistin, an adipokine promoting insulin resistance, was significantly higher in HF+MA-fed mice compared with HF controls. The insulin tolerance test revealed that the IR was higher in mice receiving the MA supplementation compared to HF controls. Moreover, the glucose tolerance test showed impairment in systemic glucose homeostasis in MA-fed mice. Analyses of liver samples showed a trend towards an increase in liver TG upon MA feeding. However, markers of oxidative stress and inflammation were reduced in the liver of mice fed an MA diet compared to controls. Taken together, our data suggest that chronic administration of MA in diet exacerbates obesity-associated insulin resistance and this effect is mediated in part, via increased AT inflammation and increased secretion of resistin. [ABSTRACT FROM AUTHOR]