Increased literature support the pathogenetic role of dysfunctional energetic metabolism in the setup and progression of organ damage and failure. Genetic diseases often offer the possibility to investigate pathogenetic mechanisms. In particular, excessive cardiac damage is the most frequent cause of mortality in Fabry disease (FD), a genetic condition caused by deficient α-galactosidase A (GLA) activity, leading to globotriaosylceramide (Gb3) accumulation. Beyond Gb3 storage, metabolic alterations and mitochondrial dysfunction, supported by in vitro evidence or studies in other tissues, may contribute to FD cardiomyopathy. This study investigated, for the first time, the mechanisms of mitochondrial involvement in FD, its role in determining cardiac manifestations, and its potential as a therapeutic target. We used a humanized FD mouse model (R301Q-Tg/GLA knockout), along with derived embryonic fibroblasts and neonatal and adult cardiomyocytes, to assess mitochondrial function across the lifespan. FD cells showed impaired mitophagy, reduced mitochondrial respiration, and increased reactive oxygen species production. Importantly, this mitochondrial dysfunction exacerbated the lysosomal deficit in FD cells, forming a vicious cycle. In cardiomyocytes, these alterations progressed with age, leading to the accumulation of dysfunctional mitochondria, energetic failure, and, in adult hearts, terminal mitochondrial damage and apoptosis. These events ultimately result in cardiac remodeling and dysfunction, including hypertrophy and diastolic impairment. Indeed, L-arginine supplementation, which promotes NO/PGC-1α-dependent mitochondrial rescue, prevented the development of cardiac abnormalities in FD mice. Our findings identify early mitochondrial dysfunction as a key driver of FD cardiomyopathy and support mitochondrial targeting, including L-arginine supplementation, as a promising adjuvant therapeutic strategy. The mechanistic link between lysosomal dysfunction, altered mitochondrial turnover, and energetic collapse emerges as a key targetable pathway in organ damage, extending beyond FD.

Anthracycline-induced cardiotoxicity remains a major limitation in the clinical use of agents such as doxorubicin (DOXO), adversely affecting both quality of life and long-term outcomes in patients with cancer. Chronic inflammation has been increasingly recognized as a central mechanism underlying DOXO-mediated cardiac injury; however, the specific immune mediators involved are not fully elucidated. The present study aimed to define the role of interleukin-1β (IL-1β), a key pro-inflammatory cytokine, in the development of cardiac dysfunction following DOXO exposure, and to assess the therapeutic potential of its inhibition using 01BSUR, a surrogate of canakinumab.Using a murine model of DOXO-induced cardiotoxicity, we show that DOXO administration leads to elevated circulating levels of IL-1β, which are significantly associated with impaired cardiac function. Notably, T lymphocytes, rather than macrophages, were identified as the predominant source of IL-1β among circulating immune cells. Mechanistically, DOXO triggered activation of the canonical inflammasome pathway, as evidenced by NFκB phosphorylation, caspase-1 cleavage, and subsequent IL-1β maturation. Pharmacological inhibition with 01BSUR, an anti-interleukin-1β monoclonal antibody, attenuated inflammasome activation, reduced both systemic and myocardial inflammation, and resulted in significant improvement in cardiac functional parameters.Taken together, our findings identify T lymphocyte–derived IL-1β as a previously unrecognized mediator of DOXO-induced cardiotoxicity and support IL-1β inhibition as a promising translational strategy to mitigate cardiac injury in patients undergoing anthracycline-based chemotherapy.

Hypoxia, a condition characterized by a temporary lack of oxygen, causes mitochondrial damage, which in turn leads to endothelial dysfunction. G-protein-coupled receptor kinase 2 (GRK2) plays a key role in vascular homeostasis and remodeling, influencing endothelial function through various pathways. GRK2 moves within the cellular compartments and is linked to mitochondrial function and biogenesis, promoting ATP production and protecting against oxidative stress and cell death. The present study examined how mitochondrial GRK2 accumulation affects vascular reactivity and endothelial function in transient hypoxic conditions. Using a cloning strategy, we employed a small peptide (10aa) TAT-conjugated based on the pleckstrin homology domain of GRK2 to redirect GRK2 from the plasma membrane to the mitochondria. Mitochondrial accumulation of GRK2 increases vasodilatory responses in isolated swine artery segments, indicating potential therapeutic applications for cardiovascular disorders. Furthermore, in endothelial cells, GRK2 accumulation within mitochondria protects membrane potential, mitochondrial mass and prevents oxidative damage and cell death caused by transient hypoxia. Our findings show that GRK2 accumulation in mitochondria represents a potential therapeutic target to prevent transient hypoxia-induced damage.

Emerging evidence indicates that the relationship between coronavirus disease 2019 (COVID-19) and diabetes is 2-fold: 1) it is known that the presence of diabetes and other metabolic alterations poses a considerably high risk to develop a severe COVID-19; 2) patients who survived a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have an increased risk of developing new-onset diabetes. However, the mechanisms underlying this association are mostly unknown, and there are no reliable biomarkers to predict the development of new-onset diabetes. In the present study, we demonstrate that a specific microRNA (miR-34a) contained in circulating extracellular vesicles released by endothelial cells reliably predicts the risk of developing new-onset diabetes in COVID-19. This association was independent of age, sex, body mass index (BMI), hypertension, dyslipidemia, smoking status, and D-dimer. SIGNIFICANCE STATEMENT: We demonstrate for the first time that a specific microRNA (miR-34a) contained in circulating extracellular vesicles released by endothelial cells is able to reliably predict the risk of developing diabetes after having contracted coronavirus disease 2019 (COVID-19). This association was independent of age, sex, body mass index (BMI), hypertension, dyslipidemia, smoking status, and D-dimer. Our findings are also relevant when considering the emerging importance of post-acute sequelae of COVID-19, with systemic manifestations observed even months after viral negativization (long COVID).

Fabry disease (FD) is a lysosomal storage disorder due to the impaired activity of the α-galactosidase A (GLA) enzyme which induces Gb3 deposition and multiorgan dysfunction. Exercise intolerance and fatigue are frequent and early findings in FD patients, representing a self-standing clinical phenotype with a significant impact on the patient's quality of life. Several determinants can trigger fatigability in Fabry patients, including psychological factors, cardiopulmonary dysfunctions, and primary alterations of skeletal muscle. The “metabolic hypothesis” to explain skeletal muscle symptoms and fatigability in Fabry patients is growing acknowledged. In this report, we will focus on the primary alterations of the motor system emphasizing the role of skeletal muscle metabolic disarrangement in determining the altered exercise tolerance in Fabry patients. We will discuss the most recent findings about the metabolic profile associated with Fabry disease offering new insights for diagnosis, management, and therapy.

Reactive oxygen species (ROS) are important signaling molecules, physiologically synthesized by oxygen metabolism [...]

Objective: Left ventricular hypertrophy (LVH) and dysfunction are the main causes of death in patients with Fabry Disease (FD). Identification of clinical predictors of FD evolution is crucially important for the correct timing of therapeutic intervention. On this ground, we aim to evaluate the impact of hypertension (H) as a predictor of (LVH) progression in FD. Design and method: We compared the FD database (319 patients) with patients from the URRAH study [>15000 patients] for H, indexed ventricular mass (LVMi) and calculated the odds ratio (OR) for LVH development. In a murine model of FD (tg-R301Q/KO mice) we chronically infused phenylephrine (PE,100 mg/Kg, 14-Days) by subcutaneous implantation of miniosmotic pump to increase blood pressure. Results: H in FD compared to URRAH exploded the LVH-OR by 6.3 times. In H patients, LVMi is significantly higher in FD than URRAH patients (FD, no H:98.8±47; FD, H:148.8±67.5 g/m2 p<0.01; URRAH, no H:103.6±29.6; U, H:112.4±31.3 g/m2, p<0.01). The multivariate analysis for sex and age indicated that FD and hypertension interact as independent risk factors for LVH. PE-exposure induced a comparable increase in systolic and diastolic blood pressure in FD and control mice. However, in FD mice PE induced a larger increase of LVMi, alongside with higher Heart-body weight ratio, and higher ANP and MEF2 cardiac levels. In FD heart, PE caused energetic stress signaling activation suggesting the potential involvement of AMPK-FOX03-axis in the hypertrophic response of FD-heart under hemodynamic stress. Conclusions: Our data suggest that H is associated with a higher risk of LVH, representing a clinical predictor of a worsened evolution of FD cardiac phenotype. Data from the murine model confirm the exaggerated hypertrophic response to H of FD heart, probably due to energetic stress induced by the increased cardiac workload.

IntroductionFabry's disease is an X-linked lysosomal storage disorder caused by reduced activity of α-galactosidase A (GAL), leading to premature death on account of renal, cardiac, and vascular organ failure. Accumulation of the GAL substrate globotriaosylceramide (Gb3) in endothelial and smooth muscle cells is associated with early vascular cell damage, suggesting endothelial dysfunction as a driver of cardiorenal organ failure. Here, we studied the vascular expression of the key angiogenic factors, VEGFα and its antagonist angiostatin, in Fabry α-GAL-Tg/KO mice and determined circulating VEGFα and angiostatin serum levels in patients with Fabry’s disease and healthy controls.MethodsCryopreserved aortic vessels from six α-GAL-Tg/KO and six wild-type (WT) mice were obtained and VEGFα and angiostatin levels were determined by performing Western blot analysis. VEGFα expression was visualized by an immunohistochemical staining of paraffin aortic rings. In addition, VEGFα and angiostatin serum levels were measured by using an enzyme-linked immunosorbent assay in 48 patients with genetically verified Fabry's disease (50% male) and 22 healthy controls and correlated with disease severity markers such as lyso-Gb3, albuminuria, NTproBNP, high-sensitive troponin T (hsTNT), and myocardial wall thickness.ResultsIt was found that there was a significant increase in VEGFα protein expression (1.66 ± 0.35 vs. 0.62 ± 0.16, p = 0.0009) and a decrease in angiostatin expression (0.024 ± 0.007 vs. 0.053 ± 0.02, p = 0.038) in aortic lysates from α-GAL-Tg/KO compared with that from WT mice. Immunohistochemical staining revealed an adventitial VEGFα signal in α-GAL-Tg/KO mice, whereas no VEGFα signal could be detected in WT mice aortas. No differences in aortic angiostatin expression between α-GAL-Tg/KO- and WT mice could be visualized. The serum levels of VEGFα were significantly upregulated in patients with Fabry’s disease compared with that in healthy controls (708.5 ± 426.3 vs. 458.5 ± 181.5 pg/ml, p = 0.048) and positively associated with albuminuria (r = 0.82, p < 0.0001) and elevated NTproBNP (r = 0.87, p < 0.0001) and hsTNT values (r = 0.41, p = 0.048) in male patients with Fabry’s disease. For angiostatin, no significant difference was found between patients with Fabry’s disease and healthy controls (747.6 ± 390.3 vs. 858.8 ± 599.3 pg/ml).DiscussionIn conclusion, an overexpression of VEGFα and downregulation of its counter player angiostatin in aortic tissue of α-GAL-Tg/KO mice support the hypothesis of an underlying vasculopathy in Fabry's disease. Elevated VEGFα serum levels were also observed in patients with Fabry’s disease and were positively associated with elevated markers of organ manifestation in males. These findings suggest that angiogenetic markers, such as VEGFα, may be potentially useful biomarkers for the detection of endothelial dysfunction in classical Fabry's disease.

In patients with type II diabetes, the development of diabetic cardiomyopathy (DC) is associated with a high risk of mortality. Left ventricular hypertrophy, diastolic dysfunction, and exercise intolerance are the first signs of DC. The underlying mechanisms are not fully elucidated, and there is an urgent need for specific biomarkers and molecular targets for early diagnosis and treatment. Mitochondrial alterations play a key role in the development of DC, and microRNAs regulating mitochondrial function are emerging as potential biomarkers of metabolic stress in DC. L-Arginine (Arg) supplementation has been shown to be an effective strategy for improving mitochondrial function and energetics, with a significant impact on physical performance. The aim of the current study was to evaluate the effects of Arg supplementation on cardiac mitochondrial function, DC development, and relative phenotypes including exercise intolerance. We used db/db mice as a model of type II diabetes, chronically treated with Arg (1 mg/kg/day) for 12 weeks. Arg-treated db/db mice showed preserved diastolic function and left ventricular morphology compared with untreated diabetic mice. Arg supplementation also improved exercise tolerance and the propensity to physical activity. Mitochondrial respiration was significantly increased in cardiomyocytes isolated from treated db/db mice, as well as in diabetic cardiomyocytes treated with Arg in vitro. The improvement of cardiac mitochondrial function in db/db + Arg mice was associated with an increase in PGC-1-alpha levels, mitochondrial biogenesis, recycling, and antioxidant capacity. Arg treatment prevented the accumulation of circulating and cardiac miR-143 in db/db mice, which is an index of metabolic stress and activation of mitochondrial damage mechanisms. In conclusion, Arg supplementation is effective in preventing the development of DC, preserving diastolic function and exercise tolerance by improving mitochondrial fitness and homeostasis. Additionally, miR-143 could potentially be employed to monitor cardiac metabolic stress and the effects of Arg treatment in diabetes.

Fabry disease (FD), also known as Anderson-Fabry disease, is a hereditary disorder of glycosphingolipid metabolism, caused by a deficiency of the lysosomal alpha-galactosidase A enzyme. This causes a progressive accumulation of glycosphingolipids in tissues and organs which represents the main pathogenetic mechanism of FD. The disease is progressive and multisystemic and is characterized by early symptoms and late complications (renal, cardiac and neurological dysfunction). Fatigue and exercise intolerance are early common symptoms in FD patients but the specific causes are still to be defined. In this narrative review, we deal with the contribution of cardiac and pulmonary dysfunctions in determining fatigue and exercise intolerance in FD patients.

Adrenergic receptors (AR) are essential regulators of vascular physiology and are largely used as pharmacological targets. This chapter will review the main roles of the vascular AR in both the endothelium and vascular smooth muscle. We will discuss the ability of ARs to regulate key functions in endothelial and smooth muscle cells and their involvement in several pathologic conditions such as hypertension, atherosclerosis, and heart failure.

Abstract Introduction Calcific aortic valve stenosis (CAVS) is a clinically relevant issue due to the lack of drugs for prevention or treatment. CAVS is driven by endothelial dysfunction and inflammation. A novel therapeutic strategy should target specific molecules involved in the regulation of both endothelial function and immune responses. G protein-coupled receptor kinase 2 (GRK2) regulates desensitization and downregulation of G protein-coupled receptors, and is able to interact with an extensive repertoire of proteins. We previously demonstrated that the lack of this protein in the endothelium promotes vascular inflammation and atherosclerosis in mice due to increased mitochondrial reactive oxygen species (ROS). Aim This study aimed to evaluate the role of GRK2 in Aortic Valve Calcification (AVC) by in vivo and in vitro studies. Methods To reach our purpose we first evaluated the expression of GRK2 in aortic valve of patient displaying fibrotic or calcific lesions of valve leaflets. Then, we evaluated GRK2 expression in mitochondria fraction from EC isolated from CAVS patients (VEC) vs control ECs upon Angiotensin II (AngII) stimulation (1µM). We also performed histological analysis by using 12 months old mice with selective endothelial knock-out of GRK2 (Tie2CRE-GRK2fl/fl) compared to control (GRK2fl/fl) to evaluate the presence of microcalcification in the aortic valve. Finally, we cloned a small sequence of the PH domain of ßARKct into the pcDNA3 to induce GRK2 localization into mitochondria. Results Immunofluorescence staining of aortic valve leaflets revealed that GRK2expression is more abundant in calcific lesion instead of fibrotic valve. In vitro, we observed that AngII is able to upregulate GRK2 mitochondrial localization in a time-dependent manner in ECs. Otherwise in VEC the stimulation with Ang II is not able to further induce GRK2 mitochondrial localization. Histological analysis revealed that Tie2CRE-GRK2fl/fl mice of 12 months-old display presence of microcalcification, more pronounced than GRK2fl/fl thus demonstrating that the lack of GRK2 in the EC accelerates the calcific degeneration of the aortic valve in mice. Finally, we cloned several small sequences of the PH domain of ßARKct into the pcDNA3.1 plasmid, named as PH#1-4. We found that the transfection into HEK293 cells of the PH#3 potently increased GRK2 localization into the mitochondria as compared to ßARKct, PH4, and pcDNA3.1 as control. PH3 also determined increased biogenesis and reduced ROS production after AngII stimulation. These data support the concept that a smaller portion of the PH domain of ßARKct can reproduce its biological effect Conclusions In conclusion, our data suggest a direct involvement of GRK2 in the pathogenesis of CAVS. Intracellular re-localization of GRK2 could be a novel strategy to prevent AVC in a pathophysiological condition such as ageing