Heart failure is a prevalent disease worldwide. While it is well accepted that heart failure involves changes in myocardial energetics, what alterations that occur in fatty acid oxidation and glucose oxidation in the failing heart remains controversial. The goal of the study are to define the energy metabolic profile in heart failure induced by obesity and hypertension in aged female mice, and to attempt to lessen the severity of heart failure by stimulating myocardial glucose oxidation. 13-Month-old C57BL/6 female mice were subjected to 10 weeks of a 60

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 β-blocker and a biased agonist that exhibits agonist-like effects through β 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 β 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.

AIMS:Heart failure with preserved ejection fraction (HFpEF) is a prevalent disease worldwide. While it is well established that alterations of cardiac energy metabolism contribute to cardiovascular pathology, the precise source of fuel used by the heart in HFpEF remains unclear. The objective of this study was to define the energy metabolic profile of the heart in HFpEF. METHODS AND RESULTS:Eight-week-old C57BL/6 male mice were subjected to a '2-Hit' HFpEF protocol [60% high-fat diet (HFD) + 0.5 g/L of Nω-nitro-L-arginine methyl ester]. Echocardiography and pressure-volume loop analysis were used for assessing cardiac function and cardiac haemodynamics, respectively. Isolated working hearts were perfused with radiolabelled energy substrates to directly measure rates of fatty acid oxidation, glucose oxidation, ketone oxidation, and glycolysis. HFpEF mice exhibited increased body weight, glucose intolerance, elevated blood pressure, diastolic dysfunction, and cardiac hypertrophy. In HFpEF hearts, insulin stimulation of glucose oxidation was significantly suppressed. This was paralleled by an increase in fatty acid oxidation rates, while cardiac ketone oxidation and glycolysis rates were comparable with healthy control hearts. The balance between glucose and fatty acid oxidation contributing to overall adenosine triphosphate (ATP) production was disrupted, where HFpEF hearts were more reliant on fatty acid as the major source of fuel for ATP production, compensating for the decrease of ATP originating from glucose oxidation. Additionally, phosphorylated pyruvate dehydrogenase levels decreased in both HFpEF mice and human patient's heart samples. CONCLUSION:In HFpEF, fatty acid oxidation dominates as the major source of cardiac ATP production at the expense of insulin-stimulated glucose oxidation.

A new class of benzimidazole derivatives bearing bis-triazole or bis-thiosemicarbazide structure was designed and synthesized as potential inhibitors of epidermal growth factor receptor (EGFR) tyrosine kinase. In vitro EGFR kinase enzyme inhibition properties were determined in comparison with erlotinib and compound (6b) containing propyl side chain at the 4th position of triazole rings showed 13.8% inhibition. Molecular docking studies were performed and docking score and binding energy were established. The most active compound formed a hydrogen bond between the Asn818 and triazole NH at the 2nd position of the benzimidazole skeleton. Predicted ADME profiles of the compounds were calculated and found to be within the appropriate reference ranges.

Background: Beta arrestins had been known as intracellular adaptors that uncouple and inactivate the G proteincoupled receptors that they interact with. Their roles as signal initiators for some receptors have recently been recognized. Scope of review: In this review, we focused on their role in mediating metabolic modulation primarily in relation to insulin signaling. Commenced by the upstream receptor, they seem to act like intracellular hubs that divert the metabolic profile of the cell. The amount of metabolic substrates in circulation and their usage/deposition by tissues are controlled by the contribution of all systems in the organism. This control is enabled by the release of hormones such as insulin, glucagon and glucagon-like peptide-1. Intriguingly, some ligands -either agonists or antagonists-of different classes of receptors have preferential properties mediated by beta arrestins. This is not surprizing considering that substrate supply and usage should parallel physiological function such as hormone release or muscle contraction. Major conclusions: Available data indicate that beta arrestins conduct the regulatory role in insulin secretion and action. They may be good candidates to target when the upstream signal demands the function that may compromise the cell. An example is carvedilol that is protective by preventing the stimulatory effects of excessive catecholamines, stimulates mitochondrial function and has preferential clinical outcomes in metabolic disorders.

BACKGROUND:Sexual dysfunction may indicate severe endocrine diseases. Recent research has suggested a link between hypothyroidism, low testosterone (T) levels, and erectile dysfunction (ED); however, the exact cause is unknown.AIM:We sought to investigate possible beneficial effects of levothyroxine and T alone or in combination on ED in propylthiouracil (PTU)-induced hypothyroid rats.METHODS:Adult Wistar rats (n = 35) were divided into 5 groups: control, PTU-induced hypothyroidism, PTU + levothyroxine, PTU + Sustanon (a mixture of 4 types of T: propionate, phenylpropionate, isocaproate, and decanoate) and PTU + levothyroxine + Sustanon. PTU was given in drinking water for 6 weeks. Four weeks after PTU administration, levothyroxine (20 μg microgram kg/day, oral) and Sustanon (10 mg/kg/week, intramuscular) were given for 2 weeks. Serum levels of total T, triiodothyronine (T3), and thyroxine (T4) were determined. In vivo erectile response and in vitro relaxant responses were measured. Localization of neuronal nitric oxide synthase (nNOS), endothelial NOS (eNOS), and phosphodiesterase type 5 (PDE5) were determined using immunohistochemical analysis. The relative area of smooth muscle to collagen was measured using Masson trichrome staining.OUTCOMES:Outcome variables included in vivo erectile function, in vitro relaxant and contractile responses of corpus cavernosum (CC) strips; protein localization of eNOS, nNOS, and PDE5; and smooth muscle content in penile tissue.RESULTS:The rat model of hypothyroidism showed a significant decline in serum levels of total T, T3, and T4. Levothyroxine increased T3 and T4 levels, whereas Sustanon normalized only total T levels. Combined treatment enhanced all hormone levels. Rats with hypothyroidism displayed the lowest erectile response (P < 0.001 vs controls). Combined treatment returned reduced responses, while partial amelioration was observed after levothyroxine and Sustanon treatment alone. Acetylcholine (P < 0.01 vs controls), electrical field stimulation (P < 0.001 vs controls), and sildenafil-induced relaxant responses (P < 0.05 vs controls) were decreased in the CC strips from hypothyroid rats. The combined treatment increased the reduction in relaxation responses. Levothyroxine and Sustanon restored decreases in eNOS and nNOS expression in the hypothyroid group. There was no significant difference in PDE5 expression among groups. Monotreatment partially enhanced reduced smooth muscle mass, while combined therapy completely recovered.CLINICAL IMPLICATIONS:The combination of thyroid hormones and T is likely to be a therapeutic approach for treatment of hypothyroidism-induced ED in men.STRENGTHS AND LIMITATIONS:Beneficial effects of levothyroxine and Sustanon treatment were shown in vitro and in vivo in PTU-induced hypothyroid rats. The main limitation of the study was the lack of measurement of androgen-sensitive organ weights and luteinizing hormone, follicle-stimulating hormone, and prolactin levels.CONCLUSION:These findings demonstrate that neurogenic and endothelium-dependent relaxation responses are reduced by hypothyroidism, which is detrimental to T levels and erectile responses. Levothyroxine and Sustanon combination medication was able to counteract this effect.

ABSTRACT Introduction The endocrine disease frequently interrupts sexual function, and sexual dysfunction may signal serious endocrine disease. Recent studies have claimed an association with hypothyroidism, low testosterone (T) levels and erectile dysfunction (ED), but causality is unclear. There is no study on the experimental model of hypothyroidism that was induced in rats by administration of propylthiouracil (PTU). Objective The purpose of this study was to investigate the deleterious effects of PTU-induced hypothyroidism on ED and T levels. In addition, Levothyroxine is known worldwide as the most common and least effective drug for controlling hypothyroidism. Methods Adult Sprague-Dawley rats (n = 35) were divided into five groups; control, PTU-induced hypothyroidism, PTU+ Levothyroxine, PTU+ Sustanon (a mixture of 4 types of T: propionate, phenylpropionate, isocaproate, decanoate) and PTU+ Levothyroxine + Sustanon. PTU was given in drinking water (0.05%) for 6 weeks. 4 weeks after the beginning of PTU treatment, Levothyroxine (20 mg/kg/day, oral) and Sustanon (10 mg/kg, I.M., once/week) were given for 2 weeks. Serum levels of total T, triiodothyronine (T3) and thyroxine (T4) were determined. The ratio of intracavernosal pressure (ICP) to mean arterial pressure (MAP) and total ICP were measured by cavernous nerve stimulation. The relaxant and contractile responses were evaluated on in vitro preparations of corpus cavernosum (CC) strips. The expression and localization of neuronal (nNOS), endothelial NOS (eNOS) and phosphodiesterase type 5 (PDE5) were determined using Western blotting and immunohistochemistry. The relative area of smooth muscle to collagen was measured using Masson trichrome staining. Results The rat model of hypothyroidism showed a significant decline in serum levels of total T, T3 and T4. Levothyroxine increased T3 and T4 levels while Sustanon normalized only total T levels. In addition, combined treatment of Levothyroxine and Sustanon enhanced all hormone levels. Rats with hypothyroidism displayed the lowest ICP/MAP ratio and total ICP for 7.5 V (P < .001 vs controls). Combined treatment returned reduced ICP/MAP and total ICP responses, while partial amelioration was observed after Levothyroxine and Sustanon treatment alone. In vitro endothelium-dependent acetylcholine-caused relaxation at 1 nM (P < .001 vs controls), electrical field stimulation-induced relaxant response at 20 Hz (P < .001 vs controls) and sildenafil-induced relaxation at 10 µM (P < .05 vs controls) were decreased in the CC strips from hypothyroid rats. The treatment with Levothyroxine and Sustanon increased the reduction in relaxation responses. Decreased in the expressions of eNOS and nNOS and increased in the expressions of PDE5 in the hypothyroid group were restored by Levothyroxine and Sustanon. Mono-treatment partially enhanced reduced smooth muscle mass while combined therapy completely recovered. Conclusions These results show that hypothyroidism adversely affects T levels and erectile responses via decreasing neurogenic and endothelium-dependent relaxation responses which were reversed by the combination therapy with Levothyroxine and Sustanon. Even though the associated alterations in T levels, ED and its reversibility indicate an exact role of thyroid hormones in the erection physiology. Disclosure No

Epidermal growth factor receptor (EGFR), one of the important targets in the development of the anticancer compound, is a member of the ErbB receptor tyrosine kinase receptor family and is highly expressed in solid tumors. Inhibition of EGFR is important for cancer treatment to inhibit the progression and growth of EGFR-expressing tumor cells. Agents targeting EGFR are successful drugs involved in the treatment of various cancers, particularly colorectal, head, neck, lung, and breast cancers. In this study, the design of some novel benzimidazole compounds that can interact with EGFR kinase enzyme, synthesis and analysis of these compounds, and evaluation of their biological activities in vitro was aimed. To reach the target compounds, by reacting acid hydrazides with alkyl isothiocyanates, thiosemicarbazides were formed, then cyclization of these compounds with concentrated sulfuric acid or sodium hydroxide, thiadiazole, or triazole derivatives were obtained. As a result of the study, a total of 38 new benzimidazole derivatives was obtained, and the structures of these compounds were clarified by elemental analysis, mass, H-1, and C-13 NMR spectroscopy. Also, the structure of compound 4c was proven by X-ray crystallography. Molecular docking studies of the synthesized compounds have also been carried out, some molecules with high docking scores have been selected and EGFR kinase inhibitor properties have been tested. Among the compounds tested, it was determined that the most active compound was 12a, which inhibited 68% EGFR at a concentration of 10 mu M.

AIMS:Ivabradine (IVA) reduces heart rate (HR) by inhibiting hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in sinoatrial node. Studies suggest that IVA has other beneficial effects on cardiovascular system that are not related to its effect on HR such as prevention of endothelial injury and the antioxidant effects. In addition to sinoatrial node, HCN channels exist in other tissues and their expression pattern differs in certain pathologies such as hypertension and hypertrophy. We investigated the mechanism of IVA effect in the setting of streptozotocin (STZ)-induced cardiovascular damage. Direct effects of IVA and their mechanism on thoracic aorta as well as possible prevention of vascular dysfunction in diabetes were investigated in this study. METHODS AND RESULTS:The effects of IVA on vascular function were investigated in control and STZ-diabetic rats. Some control and diabetic rats were treated with IVA. IVA treatment prevented diabetes-induced increase in plasma p-selectin and vascular cell adhesion molecule-1 levels and the decrease in nitric oxide content in the aortas of diabetic animals. When added to isolated organ bath, IVA induced concentration-dependent relaxations in thoracic aorta. Pre-incubation with Nω-Nitro- L -arginine methyl ester reduced IVA-induced relaxations. Expression patterns of all isoforms of HCN proteins were affected by both diabetes and IVA treatment. CONCLUSION:IVA improves vascular function in diabetes and HCN channels support vascular activity against damaging effects of diabetes. IVA may be added to prevent diabetic cardiovascular dysfunction with these beneficial effects that are unrelated to its primary mechanism of action.

Background and Purpose Carvedilol is a third-generation beta-adrenoceptor antagonist, which also stimulates beta-arrestins. beta-arrestins initiate intracellular signalling and are involved in insulin release and sensitivity. Carvedilol is superior in effectiveness to other drugs that are used for similar indications and does not cause insulin resistance or diabetes, which can occur with other beta-antagonists. We have shown that carvedilol increased glucose usage in C2C12 cells. We investigate the biased agonist efficacy of carvedilol on beta-arrestins. Experimental Approach Streptozotocin (STZ)-induced diabetes rat model was used to induce metabolic and cardiac disorders. After 8 weeks of diabetes, animals were treated with carvedilol or vehicle for another 4 weeks. In vitro heart function was evaluated at baseline as well as with increasing concentrations of isoprenaline. Effects of diabetes and carvedilol treatment on beta-arrestins, ERK, PPAR alpha, CD36 proteins and pyruvate kinase activity were evaluated. beta-arrestins were silenced in C2C12 cells by using siRNA. Acute effects of carvedilol on ERK, CD36, mitochondrial transcription factor A, cardiolipin proteins and citrate synthase activity were investigated. Key Results Carvedilol reversed the deterioration of cardiac function in diabetes and diabetes-induced decrease in beta-arrestins in rats. Carvedilol decreased the expression of CD36 in diabetes and increased mitochondrial transcription factor A and cardiolipin proteins. Silencing of beta-arrestins in cells prevented the effects of carvedilol on these proteins. Conclusion and Implications The metabolic effects of carvedilol seem to be related to biased activation of beta-arrestins. Patients with cardiovascular and metabolic disorders may benefit from new compounds that selectively act on beta-arrestins.

In this study, a series of benzimidazoles bearing thiosemicarbazide chain or triazole and thiadiazole rings were designed and synthesized. Crystal and molecular structure of the compound 5c has been characterized by single crystal X-ray crystallographic analysis. EGFR kinase inhibitory potencies of synthesized compounds were compared with erlotinib in vitro and most of the compounds exhibited significant activities. Cell culture studies were also carried out for selected compounds and 12b was found to be the most active compound. To understand the binding mode of synthesized benzimidazoles, three compounds (12b, 16, 16c) were selected and placed on the binding site of EGFR tyrosine kinase based on their kinase inhibitor potencies and cell culture studies. Docking study indicated that compound 12b showed two-hydrogen bonding interactions with residues of LYS721 and THR830 at the binding pocket.

Conclusion: GA activates caspase-8 to cleave N-term of IjBa, leading to decrease of NF-jB activity and hypertrophy, consequently induces autophgy, thereby providing the molecular basis by which