Anti-androgenic therapy with finasteride improves cardiac function, attenuates remodeling and reverts pathologic gene-expression after myocardial infarction in mice

Research progress on the protective effect of hormones and hormone drugs in myocardial ischemia-reperfusion injury

Ischemic heart disease (IHD) is a condition where the heart muscle does not receive enough blood flow, leading to cardiac dysfunction. Restoring blood flow to the coronary artery is an effective clinical therapy for myocardial ischemia. This strategy helps lower the size of the myocardial infarction and improves the prognosis of patients. Nevertheless, if the disrupted blood flow to the heart muscle is restored within a specific timeframe, it leads to more severe harm to the previously deprived heart tissue. This condition is referred to as myocardial ischemia/reperfusion injury (MIRI). Until now, there is a dearth of efficacious strategies to prevent and manage MIRI. Hormones are specialized substances that are produced directly into the circulation by endocrine organs or tissues in humans and animals, and they have particular effects on the body. Hormonal medications utilize human or animal hormones as their active components, encompassing sex hormones, adrenaline medications, thyroid hormone medications, and others. While several studies have examined the preventive properties of different endocrine hormones, such as estrogen and hormone analogs, on myocardial injury caused by ischemia-reperfusion, there are other hormone analogs whose mechanisms of action remain unexplained and whose safety cannot be assured. The current study is on hormones and hormone medications, elucidating the mechanism of hormone pharmaceuticals and emphasizing the cardioprotective effects of different endocrine hormones. It aims to provide guidance for the therapeutic use of drugs and offer direction for the examination of MIRI in clinical therapy.

Finasteride delays atherosclerosis progression in mice and is associated with a reduction in plasma cholesterol in men

Finasteride is commonly prescribed to treat benign prostate hyperplasia and male-pattern baldness in cis men and, more recently, trans individuals. However, the effect of finasteride on cardiovascular disease remains elusive. We evaluated the role of finasteride on atherosclerosis using low-density lipoprotein (LDL) receptor-deficient (Ldlr-/-) mice. Next, we examined the relevance to humans by analyzing the data deposited between 2009 and 2016 in the National Health and Nutrition Examination Survey. We show that finasteride reduces total plasma cholesterol and delays the development of atherosclerosis in Ldlr-/- mice. Finasteride reduced monocytosis, monocyte recruitment to the lesion, macrophage lesion content, and necrotic core area, the latter of which is an indicator of plaque vulnerability in humans. RNA sequencing analysis revealed a downregulation of inflammatory pathways and an upregulation of bile acid metabolism, oxidative phosphorylation, and cholesterol pathways in the liver of mice taking finasteride. Men reporting the use of finasteride showed lower plasma levels of cholesterol and LDL-cholesterol than those not taking the drug. Our data unveil finasteride as a potential treatment to delay cardiovascular disease in people by improving the plasma lipid profile.

The role of androgens in pressure overload myocardial hypertrophy

Pressure overload hypertrophy of the left ventricle is a common result of many cardiovascular diseases. Androgens show anabolic effects in skeletal muscles, but also in myocardial hypertrophy. We carefully reviewed literature regarding possible effects of androgens on specific left ventricular hypertrophy in pressure overload conditions excluding volume overload conditions or generel sex differences.

Serum dihydrotestosterone levels are associated with adverse myocardial remodeling in patients with severe aortic valve stenosis before and after aortic valve replacement

Animal studies show a pivotal role of dihydrotestosterone (DHT) in pressure overload-induced myocardial hypertrophy and dysfunction. The aim of our study was to evaluate the role of DHT levels and myocardial hypertrophy and myocardial protein expression in patients with severe aortic valve stenosis (AS). Forty-three patients [median age 68 (41-80) yr] with severe AS and indication for surgical aortic valve replacement (SAVR) were prospectively enrolled. Cardiac magnetic resonance imaging including analysis of left ventricular muscle mass (LVM), fibrosis and function, and laboratory tests including serum DHT levels were performed before and after SAVR. During SAVR, left ventricular (LV) biopsies were performed for proteomic profiling. Serum DHT levels correlated positively with indexed LVM (LVMi, R = 0.64, P = 0.0001) and fibrosis (R = 0.49, P = 0.0065) and inversely with LV function (R = -0.42, P = 0.005) in patients with severe AS. DHT levels were associated with higher abundance of the hypertrophy (moesin, R = 0.52, P = 0.0083)- and fibrosis (vimentin, R = 0.41, P = 0.039)-associated proteins from LV myocardial biopsies. Higher serum DHT levels preoperatively were associated with reduced LV function (ejection fraction, R = -0.34, P = 0.035; circulatory efficiency, R = -0.46, P = 0.012; and global longitudinal strain, R = 0.49, P = 0.01) and increased fibrosis (R = 0.55, P = 0.0022) after SAVR. Serum DHT levels were associated with adverse myocardial remodeling and higher abundance in hypertrophy- and fibrosis-associated proteins in patients with severe AS. DHT may be a target to prevent or attenuate adverse myocardial remodeling in patients with pressure overload due to AS.NEW & NOTEWORTHY Serum dihydrotestosterone (DHT) levels correlated positively with the degree of hypertrophy, fibrosis, and dysfunction from cardiac magnetic resonance imaging in female and male patients with aortic valve stenosis. Left ventricular proteome profiling had been performed in this patient cohort and an association between serum DHT levels and the abundance of the hypertrophy-associated protein moesin and the fibrosis-associated protein vimentin was found.

Characterization of N-terminal RYR2 variants outside CPVT1 hotspot regions using patient iPSCs reveal pathogenesis and therapeutic potential

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a cardiac channelopathy causing ventricular tachycardia following adrenergic stimulation. Pathogenic variants in RYR2-encoded ryanodine receptor 2 (RYR2) cause CPVT1 and cluster into domains I–IV, with the most N-terminal domain involving residues 77–466. Patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) were generated for RYR2-F13L, -L14P, -R15P, and -R176Q variants. Isogenic control iPSCs were generated using CRISPR-Cas9/PiggyBac. Fluo-4 Ca²⁺ imaging assessed Ca²⁺ handling with/without isoproterenol (ISO), nadolol (Nad), and flecainide (Flec) treatment. CPVT1 iPSC-CMs displayed increased Ca²⁺ sparking and Ca²⁺ transient amplitude following ISO compared with control. Combined Nad treatment/ISO stimulation reduced Ca²⁺ amplitude and sparking in variant iPSC-CMs. Molecular dynamic simulations visualized the structural role of these variants. We provide the first functional evidence that these most proximal N-terminal localizing variants alter calcium handling similar to CPVT1. These variants are located at the N-terminal domain and the central domain interface and could destabilize the RYR2 channel promoting Ca²⁺ leak-triggered arrhythmias.

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Extreme N-terminal RyR2 variants alter calcium handling similar to classical CPVT1

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Abnormal Ca²⁺ kinetics as well as uncontrolled Ca²⁺ release underlies CPVT1

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In vitro arrhythmia studies with iPSCs show nadolol is an effective treatment

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In silico 3D modeling of RYR2 revealed pathogenicity of N-terminal variants

Sex-related differences in ventricular remodeling after myocardial infarction

The epidemiology, clinical features and outcome of myocardial infarction (MI) display significant differences between men and women. Prominent sex differences have also been suggested in left ventricular (LV) remodeling after MI. Ventricular remodeling refers to a deterioration of LV geometry and function often leading to heart failure (HF) development and an increased risk of adverse cardiovascular events. Women have a lower propensity to the acquisition of a spherical geometry and LV dysfunction. These differences can be attributed at least partially to a lower frequency of transmural infarction and smaller areas of microvascular obstruction in women, as well as to a less prominent activation of neuroendocrine systems and apoptotic, inflammatory and profibrotic pathways in women. Estrogens might play a role in this difference, which could partially persist even after the menopause because of a persisting intramyocardial synthesis of estrogens in women. Conversely, androgens may exert a detrimental influence. Future studies should better clarify sex differences in the predictors, clinical correlates, prognostic impact and disease mechanisms of remodeling, as well as the existence of sex-specific therapeutic targets. This research effort should hopefully allow to optimize the treatment of MI during the acute and post-acute phase, possibly through different therapeutic strategies in men and women, with the goal of reducing the risk of HF development and improving patient outcome.

Fibroblast GATA-4 and GATA-6 promote myocardial adaptation to pressure overload by enhancing cardiac angiogenesis

Heart failure due to high blood pressure or ischemic injury remains a major problem for millions of patients worldwide. Despite enormous advances in deciphering the molecular mechanisms underlying heart failure progression, the cell-type specific adaptations and especially intercellular signaling remain poorly understood. Cardiac fibroblasts express high levels of cardiogenic transcription factors such as GATA-4 and GATA-6, but their role in fibroblasts during stress is not known. Here, we show that fibroblast GATA-4 and GATA-6 promote adaptive remodeling in pressure overload induced cardiac hypertrophy. Using a mouse model with specific single or double deletion of Gata4 and Gata6 in stress activated fibroblasts, we found a reduced myocardial capillarization in mice with Gata4/6 double deletion following pressure overload, while single deletion of Gata4 or Gata6 had no effect. Importantly, we confirmed the reduced angiogenic response using an in vitro co-culture system with Gata4/6 deleted cardiac fibroblasts and endothelial cells. A comprehensive RNA-sequencing analysis revealed an upregulation of anti-angiogenic genes upon Gata4/6 deletion in fibroblasts, and siRNA mediated downregulation of these genes restored endothelial cell growth. In conclusion, we identified a novel role for the cardiogenic transcription factors GATA-4 and GATA-6 in heart fibroblasts, where both proteins act in concert to promote myocardial capillarization and heart function by directing intercellular crosstalk.

Pharmacological Approaches to Controlling Cardiometabolic Risk in Women with PCOS

Polycystic ovary syndrome (PCOS) is characterized by elevated androgen production and subclinical changes in cardiovascular and metabolic risk markers. Total cholesterol, high-density lipoprotein (HDL) cholesterol, fasting glucose, and fasting insulin appear to increase specifically in PCOS compared with fertile women. PCOS also confers an increased risk of cardiometabolic disease in later life. Novel biomarkers such as serum’s cholesterol efflux capacity and blood-derived macrophage activation profile may assist in more accurately defining the cardiometabolic risk profile in these women. Aldosterone antagonists, androgen receptor antagonists, 5α-reductase inhibitors, and synthetic progestogens are used to reduce hyperandrogenism. Because increased insulin secretion enhances ovarian androgen production, short-term treatment with metformin and other hypoglycemic agents results in significant weight loss, favorable metabolic changes, and testosterone reduction. The naturally occurring inositols display insulin-sensitizing effects and may be also used in this context because of their safety profile. Combined oral contraceptives represent the drug of choice for correction of androgen-related symptoms. Overall, PCOS management remains focused on specific targets including assessment and treatment of cardiometabolic risk, according to disease phenotypes. While new options are adding to established therapeutic approaches, a sometimes difficult balance between efficacy and safety of available medications has to be found in individual women.

Dual Function of iPSC-Derived Pericyte-Like Cells in Vascularization and Fibrosis-Related Cardiac Tissue Remodeling In Vitro

Myocardial interstitial fibrosis (MIF) is characterized by excessive extracellular matrix (ECM) deposition, increased myocardial stiffness, functional weakening, and compensatory cardiomyocyte (CM) hypertrophy. Fibroblasts (Fbs) are considered the principal source of ECM, but the contribution of perivascular cells, including pericytes (PCs), has gained attention, since MIF develops primarily around small vessels. The pathogenesis of MIF is difficult to study in humans because of the pleiotropy of mutually influencing pathomechanisms, unpredictable side effects, and the lack of available patient samples. Human pluripotent stem cells (hPSCs) offer the unique opportunity for the de novo formation of bioartificial cardiac tissue (BCT) using a variety of different cardiovascular cell types to model aspects of MIF pathogenesis in vitro. Here, we have optimized a protocol for the derivation of hPSC-derived PC-like cells (iPSC-PCs) and present a BCT in vitro model of MIF that shows their central influence on interstitial collagen deposition and myocardial tissue stiffening. This model was used to study the interplay of different cell types—i.e., hPSC-derived CMs, endothelial cells (ECs), and iPSC-PCs or primary Fbs, respectively. While iPSC-PCs improved the sarcomere structure and supported vascularization in a PC-like fashion, the functional and histological parameters of BCTs revealed EC- and PC-mediated effects on fibrosis-related cardiac tissue remodeling.

Phenylethanol Glycosides Protect Myocardial Hypertrophy Induced by Abdominal Aortic Constriction via ECE-1 Demethylation Inhibition and PI3K/PKB/eNOS Pathway Enhancement

Phenylethanol glycosides (CPhGs) are the core material basis of pharmacological activity in Cistanche tubulosa and have a variety of pharmacological effects. However, it is unclear whether CPhGs have an ameliorative effect on pressure overload-induced myocardial hypertrophy. In this study, male SD rats weighing (200 ± 20) g were established cardiac hypertrophy models by abdominal aortic coarctation (AAC). After operation, the rats were gavaged with corresponding medicine for 6 weeks (CPhGs 125, 250, and 500 mg/kg/d and valsartan 8.3 mg/kg/d). Echocardiography, heart weight index (HWI), cross-sectional area of cardiomyocytes (CSCA), fibrosis area, plasma endothelin 1(ET-1), and proinflammatory factors levels were detected. Our results showed that different CPhGs dosage decreased left ventricular posterior wall thickness (LVPWT), left ventricular end-diastolic diameter (LVED), HWI, CSCA, fibrosis area, ET-1, proinflammatory factors, arterial natriuretic peptide (ANP), brain natriuretic peptide (BNP), endothelin converting enzyme 1(ECE-1) mRNA levels, cyclooxygenase 2 (COX-2), high mobility group box 1 (HMGB-1) protein levels, and ECE-1 demethylation level while increasing left ventricular ejection fractions (LVEF), left ventricular fractional shortening (LVFS), phosphorylated phosphatidylinositol 3-kinase (p-PI3K), phosphorylated protein kinase B (p-PKB), and phosphorylated endothelial nitric oxide synthetase (p-eNOS). The indexes of CPhGs 250 and 500 mg/kg group were significantly different from AAC group; compared with valsartan group (AV), the indexes of CPhGs 500 mg/kg group were not significantly different. In conclusion, CPhGs ameliorated myocardial hypertrophy rats by AAC, which may be related to ECE-1 demethylation inhibition and PI3K/PKB/eNOS enhancement.

A Year in the Life of the EU-CardioRNA COST Action: CA17129 Catalysing Transcriptomics Research in Cardiovascular Disease

The EU-CardioRNA Cooperation in Science and Technology (COST) Action is a European-wide consortium established in 2018 with 31 European country members and four associate member countries to build bridges between translational researchers from academia and industry who conduct research on non-coding RNAs, cardiovascular diseases and similar research areas. EU-CardioRNA comprises four core working groups (WG1-4). In the first year since its launch, EU-CardioRNA met biannually to exchange and discuss recent findings in related fields of scientific research, with scientific sessions broadly divided up according to WG. These meetings are also an opportunity to establish interdisciplinary discussion groups, brainstorm ideas and make plans to apply for joint research grants and conduct other scientific activities, including knowledge transfer. Following its launch in Brussels in 2018, three WG meetings have taken place. The first of these in Lisbon, Portugal, the second in Istanbul, Turkey, and the most recent in Maastricht, The Netherlands. Each meeting includes a scientific session from each WG. This meeting report briefly describes the highlights and key take-home messages from each WG session in this first successful year of the EU-CardioRNA COST Action.

Androgen-Regulated Cardiac Metabolism in Aging Men

The prevalence of cardiovascular mortality is higher in men than in age-matched premenopausal women. Gender differences are linked to circulating sex-related steroid hormone levels and their cardio-specific actions, which are critical factors involved in the prevalence and features of age-associated cardiovascular disease. In women, estrogens have been described as cardioprotective agents, while in men, testosterone is the main sex steroid hormone. The effects of testosterone as a metabolic regulator and cardioprotective agent in aging men are poorly understood. With advancing age, testosterone levels gradually decrease in men, an effect associated with increasing fat mass, decrease in lean body mass, dyslipidemia, insulin resistance and adjustment in energy substrate metabolism. Aging is associated with a decline in metabolism, characterized by modifications in cardiac function, excitation-contraction coupling, and lower efficacy to generate energy. Testosterone deficiency -as found in elderly men- rapidly becomes an epidemic condition, associated with prominent cardiometabolic disorders. Therefore, it is highly probable that senior men showing low testosterone levels will display symptoms of androgen deficiency, presenting an unfavorable metabolic profile and increased cardiovascular risk. Moreover, recent reports establish that testosterone replacement improves cardiomyocyte bioenergetics, increases glucose metabolism and reduces insulin resistance in elderly men. Thus, testosterone-related metabolic signaling and gene expression may constitute relevant therapeutic target for preventing, or treating, age- and gender-related cardiometabolic diseases in men. Here, we will discuss the impact of current evidence showing how cardiac metabolism is regulated by androgen levels in aging men.

Inactivation of Sox9 in fibroblasts reduces cardiac fibrosis and inflammation

Fibrotic scarring drives the progression of heart failure after myocardial infarction (MI). Therefore, the development of specific treatment regimens to counteract fibrosis is of high clinical relevance. The transcription factor SOX9 functions as an important regulator during embryogenesis, but recent data point towards an additional causal role in organ fibrosis. We show here that SOX9 is upregulated in the scar after MI in mice. Fibroblast specific deletion of Sox9 ameliorated MI-induced left ventricular dysfunction, dilatation and myocardial scarring in vivo. Unexpectedly, deletion of Sox9 also potently eliminated persisting leukocyte infiltration of the scar in the chronic phase after MI. RNA-sequencing from the infarct scar revealed that Sox9 deletion in fibroblasts resulted in strongly downregulated expression of genes related to extracellular matrix, proteolysis and inflammation. Importantly, Sox9 deletion in isolated cardiac fibroblasts in vitro similarly affected gene expression as in the cardiac scar and reduced fibroblast proliferation, migration and contraction capacity. Together, our data demonstrate that fibroblast SOX9 functions as a master regulator of cardiac fibrosis and inflammation and might constitute a novel therapeutic target during MI.

Dihydromyricetin Attenuates Myocardial Hypertrophy Induced by Transverse Aortic Constriction via Oxidative Stress Inhibition and SIRT3 Pathway Enhancement

Dihydromyricetin (DMY), one of the flavonoids in vine tea, exerts several pharmacological actions. However, it is not clear whether DMY has a protective effect on pressure overload-induced myocardial hypertrophy. In the present study, male C57BL/6 mice aging 8⁻10 weeks were subjected to transverse aortic constriction (TAC) surgery after 2 weeks of DMY (250 mg/kg/day) intragastric administration. DMY was given for another 2 weeks after surgery. Blood pressure, myocardial structure, cardiomyocyte cross-sectional area, cardiac function, and cardiac index were observed. The level of oxidative stress in the myocardium was assessed with dihydroethidium staining. Our results showed that DMY had no significant effect on the blood pressure. DMY decreased inter ventricular septum and left ventricular posterior wall thickness, relative wall thickness, cardiomyocyte cross-sectional areas, as well as cardiac index after TAC. DMY pretreatment also significantly reduced arterial natriuretic peptide (ANP), brain natriuretic peptide (BNP) mRNA and protein expressions, decreased reactive oxygen species production and malondialdehyde (MDA) level, while increased total antioxidant capacity (T-AOC), activity of superoxide dismutase (SOD), expression of sirtuin 3 (SIRT3), forkhead-box-protein 3a (FOXO3a) and SOD2, and SIRT3 activity in the myocardium of mice after TAC. Taken together, DMY ameliorated TAC induced myocardial hypertrophy in mice related to oxidative stress inhibition and SIRT3 pathway enhancement.