Metabolomics of repetitive myocardial stunning in chronic multivessel coronary artery stenosis: Effect of non-selective and selective ß1-receptor blockers.

Chronic coronary artery stenosis can lead to regional myocardial dysfunction in the absence of myocardial infarction by repetitive stunning, hibernation or both. The molecular mechanisms underlying repetitive stunning-associated myocardial dysfunction are not clear. We used non-targeted metabolomics to elucidate responses to chronically stunned myocardium in a canine model with and without ß-adrenergic blockade treatment. After development of left ventricular systolic dysfunction induced by ameroid constrictors on the coronary arteries, animals were randomized to 3 months of placebo, metoprolol or carvedilol. We compared these two ß-blockers with their different ß-adrenergic selectivities on myocardial function, perfusion and metabolic pathways involved in tissue undergoing chronic stunning. Control animals underwent sham surgery. Dysfunction in stunned myocardium was associated with reduced fatty acid oxidation and enhanced ketogenic amino acid metabolism, together with alterations in mitochondrial membrane phospholipid composition. These changes were consistent with impaired mitochondrial function and were linked to reduced nitric oxide and peroxisome proliferator-activated receptor signalling, resulting in a decline in adenosine monophosphate-activated protein kinase. Mitochondrial changes were ameliorated by carvedilol more than metoprolol, and improvement was linked to nitric oxide and possibly hydrogen sulphide signalling. In summary, repetitive myocardial stunning commonly seen in chronic multivessel coronary artery disease is associated with adverse metabolic remodelling linked to mitochondrial dysfunction and specific signalling pathways. These changes are reversed by ß-blockers, with the non-selective inhibitor having a more favourable impact. This is the first investigation to demonstrate that ß-blockade-associated improvement of ventricular function in chronic myocardial stunning is associated with restoration of mitochondrial function. KEY POINTS: The mechanisms responsible for the metabolic changes associated with repetitive myocardial stunning seen in chronic multivessel coronary artery disease have not been fully investigated. In a canine model of repetitive myocardial stunning, we showed that carvedilol, a non-selective ß-receptor blocker, ameliorated adverse metabolic remodelling compared to metoprolol, a selective ß1-receptor blocker, by improving nitric oxide synthase and adenosine monophosphate protein kinase function, enhancing calcium/calmodulin-dependent protein kinase, probably increasing hydrogen sulphide, and suppressing cyclic-adenosine monophosphate signalling. Mitochondrial fatty acid oxidation alterations were ameliorated by carvedilol to a larger extent than metoprolol; this improvement was linked to nitric oxide and possibly hydrogen sulphide signalling. Both ß-blockers improved the cardiac energy imbalance by reducing metabolites in ketogenic amino acid and nucleotide metabolism. These results elucidated why metabolic remodelling with carvedilol is preferable to metoprolol when treating chronic ischaemic left ventricular systolic dysfunction caused by repetitive myocardial stunning.

Improved Cardiac Performance and Decreased Arrhythmia in Hypertrophic Cardiomyopathy With Non-ß-Blocking R-Enantiomer Carvedilol.

BACKGROUND: Hypercontractility and arrhythmia are key pathophysiologic features of hypertrophic cardiomyopathy (HCM), the most common inherited heart disease. ß-Adrenergic receptor antagonists (ß-blockers) are the first-line therapy for HCM. However, ß-blockers commonly selected for this disease are often poorly tolerated in patients, where heart-rate reduction and noncardiac effects can lead to reduced cardiac output and fatigue. Mavacamten, myosin ATPase inhibitor recently approved by the US Food and Drug Administration, has demonstrated the ability to ameliorate hypercontractility without lowering heart rate, but its benefits are so far limited to patients with left ventricular (LV) outflow tract obstruction, and its effect on arrhythmia is unknown. METHODS: We screened 21 ß-blockers for their impact on myocyte contractility and evaluated the antiarrhythmic properties of the most promising drug in a ventricular myocyte arrhythmia model. We then examined its in vivo effect on LV function by hemodynamic pressure-volume loop analysis. The efficacy of the drug was tested in vitro and in vivo compared with current therapeutic options (metoprolol, verapamil, and mavacamten) for HCM in an established mouse model of HCM (Myh6R403Q/+ and induced pluripotent stem cell (iPSC)-derived cardiomyocytes from patients with HCM (MYH7R403Q/+). RESULTS: We identified that carvedilol, a ß-blocker not commonly used in HCM, suppresses contractile function and arrhythmia by inhibiting RyR2 (ryanodine receptor type 2). Unlike metoprolol (a ß1-blocker), carvedilol markedly reduced LV contractility through RyR2 inhibition, while maintaining stroke volume through α1-adrenergic receptor inhibition in vivo. Clinically available carvedilol is a racemic mixture, and the R-enantiomer, devoid of ß-blocking effect, retains the ability to inhibit both α1-receptor and RyR2, thereby suppressing contractile function and arrhythmias without lowering heart rate and cardiac output. In Myh6R403Q/+ mice, R-carvedilol normalized hyperdynamic contraction, suppressed arrhythmia, and increased cardiac output better than metoprolol, verapamil, and mavacamten. The ability of R-carvedilol to suppress contractile function was well retained in MYH7R403Q/+ iPSC-derived cardiomyocytes. CONCLUSIONS: R-enantiomer carvedilol attenuates hyperdynamic contraction, suppresses arrhythmia, and at the same time, improves cardiac output without lowering heart rate by dual blockade of α1-adrenergic receptor and RyR2 in mouse and human models of HCM. This combination of therapeutic effects is unique among current therapeutic options for HCM and may particularly benefit patients without LV outflow tract obstruction.

Antidepressant effect of carvedilol on streptozotocin-induced diabetic peripheral neuropathy mice by altering gut microbiota.

RATIONALE: Although diabetic peripheral neuropathic pain (DPNP) and depression have been recognized for many years, their co-morbidity relationship and effective treatment choices remain uncertain. OBJECTIVES: To evaluate the antidepressant effect of carvedilol on streptozotocin-induced DPNP mice, and the relationship with gut microbiota. METHODS: The hyperalgesia and depressive behaviors of mice with comorbidity of DPNP and depression were confirmed by pain threshold of the mechanical sensitivity test (MST), immobility time of the tail suspension test (TST) and the forced swimming test (FST). The anti-depressive effect and fecal gut microbiota composition were studied in DPNP mice treated with carvedilol (10 mg/kg/day), and the relationships between them were analyzed by Spearman's correlation. RESULTS: Depression was successfully induced in DPNP mice. Carvedilol can reverse the decreased mechanical pain threshold and relieve the depressive behaviors of DPNP mice, while increasing the abundance of Prevotella, Ruminococcus, Helicobacter and Desulfovibrio, and decreasing the abundance of Akkermansia and Allobaculum. CONCLUSIONS: Carvedilol can alleviate the mechanical hyperalgesia and alter gut microbiota to ameliorate the depression-like behaviors which induced by DPNP.

Obesity Is a Major Determinant of Impaired Cardiac Energy Metabolism in Heart Failure with Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) is a major health problem with limited treatment options. Although optimizing cardiac energy metabolism is a potential approach to treating heart failure, it is poorly understood what alterations in cardiac energy metabolism actually occur in HFpEF. To determine this, we used mice in which HFpEF was induced using an obesity and hypertension HFpEF protocol for 10 weeks. Next, carvedilol, a third-generation ß-blocker and a biased agonist that exhibits agonist-like effects through ß arrestins by activating extracellular signal-regulated kinase, was used to decrease one of these parameters, namely hypertension. Heart function was evaluated by invasive pressure-volume loops and echocardiography as well as by ex vivo working heart perfusions. Glycolysis and oxidation rates of glucose, fatty acids, and ketones were measured in the isolated working hearts. The development of HFpEF was associated with a dramatic decrease in cardiac glucose oxidation rates, with a parallel increase in palmitate oxidation rates. Carvedilol treatment decreased the development of HFpEF but had no major effect on cardiac energy substrate metabolism. Carvedilol treatment did increase the expression of cardiac ß arrestin 2 and proteins involved in mitochondrial biogenesis. Decreasing bodyweight in obese HFpEF mice increased glucose oxidation and improved heart function. This suggests that the dramatic energy metabolic changes in HFpEF mice hearts are primarily due to the obesity component of the HFpEF model. SIGNIFICANCE STATEMENT: Metabolic inflexibility occurs in heart failure with preserved ejection fraction (HFpEF) mice hearts. Lowering blood pressure improves heart function in HFpEF mice with no major effect on energy metabolism. Between hypertension and obesity, the latter appears to have the major role in HFpEF cardiac energetic changes. Carvedilol increases mitochondrial biogenesis and overall energy expenditure in HFpEF hearts.

The ß-Blocker Carvedilol and Related Aryloxypropanolamines Promote ERK1/2 Phosphorylation in HEK293 Cells with K A Values Distinct From Their Equilibrium Dissociation Constants as ß 2-Adrenoceptor Antagonists: Evidence for Functional Affinity.

The determination of affinity by using functional assays is important in drug discovery because it provides a more relevant estimate of the strength of interaction of a ligand to its cognate receptor than radioligand binding. However, empirical evidence for so-called, "functional affinity" is limited. Herein, we determined whether the affinity of carvedilol, a ß-adrenoceptor antagonist used to treat heart failure that also promotes extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation, differed between these two pharmacological activities. Four structurally related ß-adrenoceptor antagonists (alprenolol, carazolol, pindolol, propranolol) that also activated ERK1/2 were included as comparators to enhance our understanding of how these drugs work in the clinical setting. In HEK293 cells stably expressing the human ß 2-adrenoceptor carvedilol and related aryloxypropanolamines were partial agonists of ERK1/2 phosphorylation with potencies ([A]50s) that were lower than their equilibrium dissociation constants (K Bs) as ß 2-adrenoceptor antagonists. As the [A]50 of a partial agonist is a good approximation of its K B, then these data indicated that the affinities of carvedilol and related ligands for these two activities were distinct. Moreover, there was a significant negative rank order correlation between the [A]50 of each ligand to activate ERK1/2 and their intrinsic activities (i.e., as intrinsic activity for ERK1/2 phosphorylation increased, so did affinity). Genome editing revealed that the transducer that coupled the ß 2-adrenoceptor to ERK1/2 phosphorylation in response to carvedilol and other ß 2-adrenoceptor antagonists was Gαs. Collectively, these data support the concept of "functional affinity" and indicate that the ability of the ß 2-adrenoceptor to recruit Gαs may influence the affinity of the activating ligand. SIGNIFICANCE STATEMENT: In HEK293 cells overexpressing the human ß2-adrenoceptor carvedilol and four related aryloxypropanolamines behaved as ß2-adrenoceptor antagonists and partial agonists of ERK1/2 phosphorylation with rank orders of affinity that were distinct. These data imply that carvedilol and other ß-blockers can stabilize the ß2-adrenoceptor in different affinity conformations that are revealed when functionally distinct responses are measured. This is the basis for the pharmacological concept of "functional affinity."

Mitigation of Nitrogen Mustard-Induced Skin Injury by the ß-Blocker Carvedilol and Its Enantiomers.

The chemical warfare agent sulfur mustard and its structural analog nitrogen mustard (NM) cause severe vesicating skin injuries. The pathologic mechanisms for the skin injury following mustard exposure are poorly understood; therefore, no effective countermeasure is available. Previous reports demonstrated the protective activity of carvedilol, a US Food and Drug Administration (FDA)-approved ß-blocker, against UV radiation-induced skin damage. Thus, the current study evaluated the effects of carvedilol on NM-induced skin injuries in vitro and in vivo. In the murine epidermal cell line JB6 Cl 41-5a, ß-blockers with different receptor subtype selectivity were examined. Carvedilol and both of its enantiomers, R- and S-carvedilol, were the only tested ligands statistically reducing NM-induced cytotoxicity. Carvedilol also reduced NM-induced apoptosis and p53 expression. In SKH-1 mice, NM increased epidermal thickness, damaged skin architecture, and induced nuclear factor κB (NF-κB)-related proinflammatory genes as assessed by RT2 Profiler PCR (polymerase chain reaction) Arrays. To model chemical warfare scenario, 30 minutes after exposure to NM, 10 µM carvedilol was applied topically. Twenty-four hours after NM exposure, carvedilol attenuated NM-induced epidermal thickening, Ki-67 expression, a marker of cellular proliferation, and multiple proinflammatory genes. Supporting the in vitro data, the non-ß-blocking R-enantiomer of carvedilol had similar effects as racemic carvedilol, and there was no difference between carvedilol and R-carvedilol in the PCR array data, suggesting that the skin protective effects are independent of the ß-adrenergic receptors. These data suggest that the ß-blocker carvedilol and its enantiomers can be repurposed as countermeasures against mustard-induced skin injuries. SIGNIFICANCE STATEMENT: The chemical warfare agent sulfur mustard and its structural analog nitrogen mustard cause severe vesicating skin injuries for which no effective countermeasure is available. This study evaluated the effects of US Food and Drug Administration (FDA)-approved ß-blocker carvedilol on nitrogen mustard-induced skin injuries to repurpose this cardiovascular drug as a medical countermeasure.

Oral intake of bucillamine, carvedilol, metformin, or phenformin does not protect against UVR-induced squamous cell carcinomas in hairless mice.

Squamous cell carcinoma represents the second most common type of keratinocyte carcinoma with ultraviolet radiation (UVR) making up the primary risk factor. Oral photoprotection aims to reduce incidence rates through oral intake of photoprotective compounds. Recently, drug repurposing has gained traction as an interesting source of chemoprevention. Because of their reported photoprotective properties, we investigated the potential of bucillamine, carvedilol, metformin, and phenformin as photoprotective compounds following oral intake in UVR-exposed hairless mice. Tumour development was observed in all groups in response to UVR, with only the positive control (Nicotinamide) demonstrating a reduction in tumour incidence (23.8%). No change in tumour development was observed in the four repurposed drug groups compared to the UV control group, whereas nicotinamide significantly reduced carcinogenesis (P = 0.00012). Metformin treatment significantly reduced UVR-induced erythema (P = 0.012), bucillamine and phenformin increased dorsal pigmentation (P = 0.0013, and P = 0.0005), but no other photoprotective effect was observed across the repurposed groups. This study demonstrates that oral supplementation with bucillamine, carvedilol, metformin, or phenformin does not affect UVR-induced carcinogenesis in hairless mice.

Assessment of the Impact of Carvedilol Administered Together with Dexrazoxan and Doxorubicin on Liver Structure and Function, Iron Metabolism, and Myocardial Redox System in Rats.

Late cardiotoxicity is a formidable challenge in anthracycline-based anticancer treatments. Previous research hypothesized that co-administration of carvedilol (CVD) and dexrazoxane (DEX) might provide superior protection against doxorubicin (DOX)-induced cardiotoxicity compared to DEX alone. However, the anticipated benefits were not substantiated by the findings. This study focuses on investigating the impact of CVD on myocardial redox system parameters in rats treated with DOX + DEX, examining its influence on overall toxicity and iron metabolism. Additionally, considering the previously observed DOX-induced ascites, a seldom-discussed condition, the study explores the potential involvement of the liver in ascites development. Compounds were administered weekly for ten weeks, with a specific emphasis on comparing parameter changes between DOX + DEX + CVD and DOX + DEX groups. Evaluation included alterations in body weight, feed and water consumption, and analysis of NADPH2, NADP+, NADPH2/NADP+, lipid peroxidation, oxidized DNA, and mRNA for superoxide dismutase 2 and catalase expressions in cardiac muscle. The iron management panel included markers for iron, transferrin, and ferritin. Liver abnormalities were assessed through histological examinations, aspartate transaminase, alanine transaminase, and serum albumin level measurements. During weeks 11 and 21, reduced NADPH2 levels were observed in almost all examined groups. Co-administration of DEX and CVD negatively affected transferrin levels in DOX-treated rats but did not influence body weight changes. Ascites predominantly resulted from cardiac muscle dysfunction rather than liver-related effects. The study's findings, exploring the impact of DEX and CVD on DOX-induced cardiotoxicity, indicate a lack of scientific justification for advocating the combined use of these drugs at histological, biochemical, and molecular levels.

Carvedilol exhibits anti-acute T lymphoblastic leukemia effect in vitro and in vivo via inhibiting ß-ARs signaling pathway.

An increasing number of studies have focus upon ß-adrenergic receptor blockers and their anti-tumor effects. However, the use of Carvedilol (CVD), the third generation ß-AR blocker, has not been explored for use against T-ALL. In this study, the level of ß-ARs was explored in pediatric T-ALL patients. Moreover, the antitumor effects of CVD against T-ALL were assessed in vitro and in vivo, and the underlying mechanisms were investigated. The viability of T-ALL cells following CVD treatment was detected using a CCK-8 assay, and the apoptotic and cell cycle effects were measured using flow cytometry. The protein levels of ß-ARs, cAMP, Epac, JAK2, STAT3, p-STAT3, PI3K, p-PI3K, AKT, p-AKT, mTOR, cyclin D1, PCNA, and cleaved caspase-3 were assessed by Western blotting. In vivo experiments were used to investigate the effect of CVD on T-ALL growth in mice. The results indicated that ß-ARs were highly expressed in the newly diagnosed T-ALL cells when compared to those in the control group (P < 0.05). In vitro, CVD significantly inhibited T-ALL cell viability, promoted apoptosis and blocked the G0/G1 phase of cell cycle. After CVD treatment, the protein levels of ß-ARs, cAMP, Epac, PI3K, p-PI3K, AKT, p-AKT, mTOR, JAK2, STAT3, p-STAT3, cyclin D1 and PCNA were significantly downregulated (P < 0.05); whereas cleaved caspase-3 was significantly upregulated (P < 0.05). In vivo, the volume and weight of the xenograft tumors were significantly decreased in the CVD group (P < 0.05). CVD promoted xenograft tumor apoptosis and reduced the proportion of CEM-C1 cells in murine peripheral blood and bone marrow (P < 0.05). Our results demonstrate that ß-ARs are expressed in T-ALL. CVD has a strong antitumor effect against T-ALL and inhibits ß-AR associated signaling pathways. Therefore, CVD may provide a potential therapy for T-ALL.

Carvedilol Reduces the Neuronal Apoptosis after Ischemic Stroke by Modulating Activator of Transcription 3 Expression in vitro.

Cerebral ischemia is divided into local cerebral ischemia and diffuse cerebral ischemia. The etiology of localized cerebral ischemia includes middle cerebral artery embolism; stenosis, occlusion, or thrombosis of extracranial internal carotid artery or vertebral artery; and cerebral artery spasm. The causes of diffuse cerebral ischemia include cardiac arrest, hypotension, anemia, and hypoglycemia. However, the underlying mechanism is still unclear. In this study, we demonstrated that activator of transcription 3 (ATF3) is a hubgene in IS by bioinformatics analysis. The expression of ATF3 was increased in PC12 cells with oxygen-glucose deprivation/reoxygenation (OGD/R) treatment. ATF3 deficiency inhibited cell viability and induced cell apoptosis, whereas ATF3 overexpression showed the opposite role in cell viability and cell apoptosis. Moreover, Carvedilol as a compound targeting ATF3 also facilitated cell viability and reduced cell apoptosis. ATF3 deficiency retarded the increase in cell viability and inhibition of cell apoptosis in OGD/R-PC12 cells with Carvedilol treatment. Additionally, the decreased Bax and cleaved caspase-3 were released in OGD/R-PC12 cells with Carvedilol and siATF3 treatment, while Bcl-2 expression was inhibited in OGD/R-PC12 cells with Carvedilol and siATF3 treatment. In conclusion, Carvedilol may be a key compound targeting ATF3 in OGD/R-PC12 cells. Graphical Abstract: Carvedilol positively regulated cell viability and negatively regulated cell apoptosis in OGD/R-PC12 cells by inhibition of ATF3.

Potential cardioprotective and anticancer effects of carvedilol either free or as loaded nanoparticles with or without doxorubicin in solid Ehrlich carcinoma-bearing mice.

AIM: The aim of this study was to investigate the potential cardioprotective and anti-cancer effects of carvedilol (CAR) either free or as loaded nano-formulated with or without doxorubicin (DOX) in solid Ehrlich carcinoma (SEC)-bearing mice. It focused on assessment of cardiac damage, drug resistance, apoptosis, oxidative stress status, angiogenesis and proliferation. METHODS: CAR was loaded into poly-D,L lactic-co-glycolic acid)PLGA(or Niosomes. SEC was induced in female albino mice as an experimental model of breast cancer. Seventy-two mice were randomly divided into 9 equal groups (Normal control, Untreated-SEC, SEC + DOX, SEC + CAR-free, SEC + CAR-PLGA, SEC + CAR-Niosomes, SEC + DOX + CAR-free, SEC + DOX + CAR-PLGA and SEC + DOX + CAR-Niosomes). Tumor volume and survival rate were recorded. On day 28 from tumor inoculation, mice were sacrificed, and blood samples were collected for determination of serum lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB). One part from tumor tissues was prepared for assessment of multidrug resistance protein-1 (MDR-1), caspase-3, reduced glutathione (GSH) and malondialdehyde (MDA), while the other part was processed for histopathological examination and immunohistochemical expression of vascular endothelial growth factor (VEGF) and Ki-67. RESULTS: There was non-significant difference between CAR-free, CAR-PLGA and CAR-Niosomes as anticancer either alone or when combined with DOX. However, CAR-free demonstrated potential cardioprotective effects against cardiac damage mediated by cancer or DOX that have been enhanced using CAR-PLGA or CAR-Niosomes, but that of Niosomes outperformed them both. CONCLUSION: CAR could be used as an adjuvant therapy with DOX, especially when nanoformualted with PLGA and even better with Niosomes, without compromising its cytotoxicity against cancer cells and preventing its cardiotoxic impacts.

Synergistic combination of carvedilol, amlodipine, amitriptyline, and antibiotics as an alternative treatment approach for the susceptible and multidrug-resistant A. baumannii infections via drug repurposing.

We evaluated in vitro activity of 13 drugs used in the treatment of some non-communicable diseases via repurposing to determine their potential use in the treatment of Acinetobacter baumannii infections caused by susceptible and multidrug-resistant strains. A. baumannii is a multidrug-resistant Gram-negative bacteria causing nosocomial infections, especially in intensive care units. It has been identified in the WHO critical pathogen list and this emphasises urgent need for new treatment options. As the development of new therapeutics is expensive and time consuming, finding new uses of existing drugs via drug repositioning has been favoured. Antimicrobial susceptibility tests were conducted on all 13 drugs according to CLSI. Drugs with MIC values below 128 µg/mL and control antibiotics were further subjected to synergetic effect and bacterial time-kill analysis. Carvedilol-gentamicin (FICI 0.2813) and carvedilol-amlodipine (FICI 0.5625) were determined to have synergetic and additive effect, respectively, on the susceptible A. baumannii strain, and amlodipine-tetracycline (FICI 0.75) and amitriptyline-tetracycline (FICI 0.75) to have additive effect on the multidrug-resistant A. baumannii strain. Most remarkably, both amlodipine and amitriptyline reduced the MIC of multidrug-resistant, including some carbapenems, A. baumannii reference antibiotic tetracycline from 2 to 0.5 µg/mL, for 4-folds. All these results were further supported by bacterial time-kill assay and all combinations showed bactericidal activity, at certain hours, at 4XMIC. Combinations proposed in this study may provide treatment options for both susceptible and multidrug-resistant A. baumannii infections but requires further pharmacokinetics and pharmacodynamics analyses and in vivo re-evaluations using appropriate models.

Influence of carvedilol and thyroid hormones on inflammatory proteins and cardioprotective factor HIF-1α in the infarcted heart.

Inflammatory pathways of Toll-like receptor 4 (TLR4) and NLRP3 inflammasome contribute to acute myocardial infarction (AMI) pathophysiology. The hypoxia-inducible factor 1α (HIF-1α), however, is a key transcription factor related to cardioprotection. This study aimed to compare the influence of carvedilol and thyroid hormones (TH) on inflammatory and HIF-1α proteins and on cardiac haemodynamics in the infarcted heart. Male Wistar rats were allocated into five groups: sham-operated group (SHAM), infarcted group (MI), infarcted treated with the carvedilol group (MI + C), infarcted treated with the TH group (MI + TH), and infarcted co-treated with the carvedilol and TH group (MI + C + TH). Haemodynamic analysis was assessed 15 days post-AMI. The left ventricle (LV) was collected for morphometric and Western blot analysis. The MI group presented LV systolic pressure reduction, LV end-diastolic pressure elevation, and contractility index decrease compared to the SHAM group. The MI + C, MI + TH, and MI + C + TH groups did not reveal such alterations compared to the SHAM group. The MI + TH and MI + C + TH groups presented reduced MyD88 and NLRP3 and increased HIF-1α levels. In conclusion, all treatments preserve the cardiac haemodynamic, and only TH, as isolated treatment or in co-treatment with carvedilol, was able to reduce MyD88 and NLRP3 and increase HIF-1α in the infarcted heart.

The ß-arrestin-biased ß-adrenergic receptor blocker carvedilol enhances skeletal muscle contractility.

A decrease in skeletal muscle strength and functional exercise capacity due to aging, frailty, and muscle wasting poses major unmet clinical needs. These conditions are associated with numerous adverse clinical outcomes including falls, fractures, and increased hospitalization. Clenbuterol, a ß2-adrenergic receptor (ß2AR) agonist enhances skeletal muscle strength and hypertrophy; however, its clinical utility is limited by side effects such as cardiac arrhythmias mediated by G protein signaling. We recently reported that clenbuterol-induced increases in contractility and skeletal muscle hypertrophy were lost in ß-arrestin 1 knockout mice, implying that arrestins, multifunctional adapter and signaling proteins, play a vital role in mediating the skeletal muscle effects of ß2AR agonists. Carvedilol, classically defined as a ßAR antagonist, is widely used for the treatment of chronic systolic heart failure and hypertension, and has been demonstrated to function as a ß-arrestin-biased ligand for the ß2AR, stimulating ß-arrestin-dependent but not G protein-dependent signaling. In this study, we investigated whether treatment with carvedilol could enhance skeletal muscle strength via ß-arrestin-dependent pathways. In a murine model, we demonstrate chronic treatment with carvedilol, but not other ß-blockers, indeed enhances contractile force in skeletal muscle and this is mediated by ß-arrestin 1. Interestingly, carvedilol enhanced skeletal muscle contractility despite a lack of effect on skeletal muscle hypertrophy. Our findings suggest a potential unique clinical role of carvedilol to stimulate skeletal muscle contractility while avoiding the adverse effects with ßAR agonists. This distinctive signaling profile could present an innovative approach to treating sarcopenia, frailty, and secondary muscle wasting.

Population Pharmacokinetic-Pharmacodynamic Modeling of Carvedilol to Evaluate the Effect of Cytochrome P450 2D6 Genotype on the Heart Rate Reduction.

BACKGROUND: Carvedilol is a beta-adrenergic receptor antagonist primarily metabolized by cytochromes P450 (CYP) 2D6. This study established a carvedilol population pharmacokinetic (PK)-pharmacodynamic (PD) model to describe the effects of CYP2D6 genetic polymorphisms on the inter-individual variability of PK and PD. METHODS: The PK-PD model was developed from a clinical study conducted on 21 healthy subjects divided into three CYP2D6 phenotype groups, with six subjects in the extensive metabolizer (EM, *1/*1, *1/*2), seven in the intermediate metabolizer-1 (IM-1, *1/*10, *2/*10), and eight in the intermediate metabolizer-2 (IM-2, *10/*10) groups. The PK-PD model was sequentially developed, and the isoproterenol-induced heart rate changes were used to establish the PD model. A direct effect response and inhibitory Emax model were used to develop a carvedilol PK-PD model. RESULTS: The carvedilol PK was well described by a two-compartment model with zero-order absorption, lag time, and first-order elimination. The carvedilol clearance in the CYP2D6*10/*10 group decreased by 32.8% compared with the other groups. The inhibitory concentration of carvedilol estimated from the final PK-PD model was 16.5 ng/mL regardless of the CYP2D6 phenotype. CONCLUSION: The PK-PD model revealed that the CYP2D6 genetic polymorphisms were contributed to the inter-individual variability of carvedilol PK, but not PD.

Differential Effects of the Betablockers Carvedilol, Metoprolol and Bisoprolol on Cardiac Kv4.3 (Ito) Channel Isoforms.

Cardiac Kv4.3 channels contribute to the transient outward K+ current, Ito, during early repolarization of the cardiac action potential. Two different isoforms of Kv4.3 are present in the human ventricle and exhibit differential remodeling in heart failure (HF). Cardioselective betablockers are a cornerstone of HF with reduced ejection fraction therapy as well as ventricular arrhythmia treatment. In this study we examined pharmacological effects of betablockers on both Kv4.3 isoforms to explore their potential for isoform-specific therapy. Kv4.3 isoforms were expressed in Xenopus laevis oocytes and incubated with the respective betablockers. Dose-dependency and biophysical characteristics were examined. HEK 293T-cells were transfected with the two Kv4.3 isoforms and analyzed with Western blots. Carvedilol (100 µM) blocked Kv4.3 L by 77 ± 2% and Kv4.3 S by 67 ± 6%, respectively. Metoprolol (100 µM) was less effective with inhibition of 37 ± 3% (Kv4.3 L) and 35 ± 4% (Kv4.3 S). Bisoprolol showed no inhibitory effect. Current reduction was not caused by changes in Kv4.3 protein expression. Carvedilol inhibited Kv4.3 channels at physiologically relevant concentrations, affecting both isoforms. Metoprolol showed a weaker blocking effect and bisoprolol did not exert an effect on Kv4.3. Blockade of repolarizing Kv4.3 channels by carvedilol and metoprolol extend their pharmacological mechanism of action, potentially contributing beneficial antiarrhythmic effects in normal and failing hearts.

The Lack of Synergy between Carvedilol and the Preventive Effect of Dexrazoxane in the Model of Chronic Anthracycline-Induced Cardiomyopathy.

The anticancer efficacy of doxorubicin (DOX) is dose-limited because of cardiomyopathy, the most significant adverse effect. Initially, cardiotoxicity develops clinically silently, but it eventually appears as dilated cardiomyopathy with a very poor prognosis. Dexrazoxane (DEX) is the only FDA-approved drug to prevent the development of anthracycline cardiomyopathy, but its efficacy is insufficient. Carvedilol (CVD) is another product being tested in clinical trials for the same indication. This study's objective was to evaluate anthracycline cardiotoxicity in rats treated with CVD in combination with DEX. The studies were conducted using male Wistar rats receiving DOX (1.6 mg/kg b.w. i.p., cumulative dose: 16 mg/kg b.w.), DOX and DEX (25 mg/kg b.w. i.p.), DOX and CVD (1 mg/kg b.w. i.p.), or a combination (DOX + DEX + CVD) for 10 weeks. Afterward, in the 11th and 21st weeks of the study, echocardiography (ECHO) was performed, and the tissues were collected. The addition of CVD to DEX as a cardioprotective factor against DOX had no favorable advantages in terms of functional (ECHO), morphological (microscopic evaluation), and biochemical alterations (cardiac troponin I and brain natriuretic peptide levels), as well as systemic toxicity (mortality and presence of ascites). Moreover, alterations caused by DOX were abolished at the tissue level by DEX; however, when CVD was added, the persistence of DOX-induced unfavorable alterations was observed. The addition of CVD normalized the aberrant expression of the vast majority of indicated genes in the DOX + DEX group. Overall, the results indicate that there is no justification to use a simultaneous treatment of DEX and CVD in DOX-induced cardiotoxicity.

Acute and chronic metabolic effects of carvedilol in high-fructose, high-fat diet-fed mice: implication of ß-arrestin2 pathway.

We aimed to investigate the acute and chronic effects of carvedilol on insulin resistance in high-fructose, high-fat diet (HFrHFD) - fed mice and the implication of the ß-arrestin2 pathway. The acute effect of carvedilol (10 mg/kg, i.p.) on glucose tolerance and hepatic lipid signaling in normal and insulin resistant mice was investigated. Then, the chronic effect of carvedilol on insulin resistance and dyslipidemia in HFrHFD-fed mice was examined. Changes in ß-arrestin2 and its downstream signals in liver, skeletal muscle, and adipose tissue were measured. This involved measuring phosphatidylinositol 4,5-bisphosphate (PIP2) and diacylglycerol (DAG) levels and protein kinase B (AKT) activity. Carvedilol acutely reduced fasting blood glucose levels in both normal and insulin resistant mice without significantly affecting the glucose tolerance. These acute effects were associated with increased hepatic PIP2 but decreased hepatic DAG levels. Chronic administration of carvedilol significantly ameliorated insulin resistance and dyslipidemia in HFrHFD-fed mice. These chronic effects were associated with increased ß-arrestin2, PIP2, and AKT activity levels but decreased DAG levels in the classical insulin target tissues. In conclusion, carvedilol acutely maintains glucose homeostasis and chronically ameliorates insulin resistance and dyslipidemia in HFrHFD-fed mice. The insulin sensitizing effects of carvedilol are highly correlated with the upregulation of ß-arrestin2 pathway.

Beta-Adrenergic Blockers as a Potential Treatment for COVID-19 Patients.

More than 15 million people have been affected by coronavirus disease 2019 (COVID-19) and it has caused 640 016 deaths as of July 26, 2020. Currently, no effective treatment option is available for COVID-19 patients. Though many drugs have been proposed, none of them has shown particular efficacy in clinical trials. In this article, the relationship between the Adrenergic system and the renin-angiotensin-aldosterone system (RAAS) is focused in COVID-19 and a vicious circle consisting of the Adrenergic system-RAAS-Angiotensin converting enzyme 2 (ACE2)-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (which is referred to as the "ARAS loop") is proposed. Hyperactivation of the ARAS loop may be the underlying pathophysiological mechanism in COVID-19, and beta-adrenergic blockers are proposed as a potential treatment option. Beta-adrenergic blockers may decrease the SARS-CoV-2 cellular entry by decreasing ACE2 receptors expression and cluster of differentiation 147 (CD147) in various cells in the body. Beta-adrenergic blockers may decrease the morbidity and mortality in COVID-19 patients by preventing or reducing acute respiratory distress syndrome (ARDS) and other complications. Retrospective and prospective clinical trials should be conducted to check the validity of the hypothesis. Also see the video abstract here https://youtu.be/uLoy7do5ROo.

Potential role of carvedilol in intestinal toxicity through NF-κB/iNOS/COX-2/TNF-α inflammatory signaling pathway in rats.

BACKGROUND: The increased use of indomethacin (IND) is associated with gastrointestinal injury. This research aims to investigate the effects of a beta-blocker, carvedilol (CAR) on a rat model of IND-induced acute intestinal damage and clarify the probable underlying protective mechanisms. MATERIALS AND METHODS: Twenty-four male Wistar rats were divided into four groups. Control group: given vehicles; CAR-treated group: given 10 mg/kg/day CAR PO daily by gastric gavage for 10 consecutive days; IND-treated group: given a single Sc dose of 10 mg/kg IND at the end of the ninth day of the experiment; combined CAR/IND-treated group: given both IND and CAR. RESULTS: In the rats that received IND, severe intestinal histopathological changes together with oxidative and nitrosative intestinal stress were present biochemically and immunohistochemically. Obvious inflammatory and tissue damage were represented by the significant intestinal increases in TNF-α, COX-2, and caspase-3 together with the elevated expression of VCAM-1 adhesion molecules. Intestinal gene expression of NF-kB and COX-2 was also increased. Pretreatment with CAR significantly reversed the IND-induced intestinal toxic manifestations. CONCLUSION: CAR has beneficial intestinal protective effects. Its ameliorative action is conferred through its antioxidant, antinitrosative, anti-inflammatory, and antiapoptotic properties.