The effects of nebivolol on apoptosis in a rat infarct model

Nebivolol ameliorates sepsis-evoked kidney dysfunction by targeting oxidative stress and TGF-β/Smad/p53 pathway

Sepsis is a potential fetal organ destruction brought on through an overzealous immunologic reaction to infection, causing severe inflammation, septic shock, and damage to different organs. Although there has been progress in the identification and controlling of clinical sepsis, the fatality rates are still significant. This study, for the first time, intended to examine the possible ameliorative impact of Nebivolol, a β1-adrenergic antagonist antihypertensive drug, against nephrotoxicity resulted from cecal ligation and puncture (CLP)-induced sepsis in rats, on molecular basis. Sixty male Wistar albino rats were chosen. Oxidative stress indicators and biochemical markers of kidney activity were evaluated. Inflammatory mediators, fibrosis- and apoptosis-related proteins and gene expressions were investigated. Moreover, renal histopathological investigation was performed. CLP-induced nephrotoxicity characterized by markedly elevated serum levels of creatinine, blood urea nitrogen, uric acid, and renal malondialdhyde. On the other hand, it decreased serum total protein level, renal superoxide dismutase activity and reduced glutathione level. Additionally, it significantly elevated the renal inflammatory mediators (tumor necrosis factor-alpha, ilnerlukin (IL)-6, and IL-1β) and Caspase-3 protein, reduced IL-10 level, amplified the expression of transforming growth factor-beta 1 (TGF-β1), p-Smad2/3 and alpha-smooth-muscle actin proteins, downregulated the B cell lymphoma-2 (Bcl-2) gene and elevated the transcription of Bcl-2-associated X-protein (Bax), p53 and Nuclear factor-kappa B (NF-κB) genes. Furtheremor, kidney tissues exhibited significant histopathological changes with CLP. On the contrary, Nebivolol significantly improved all these biochemical changes and enhanced the histopathological alterations obtained by CLP. This research showed, for the first time, that Nebivolol effectively mitigated the CLP-induced kidney dysfunction via its antioxidant, antifibrotic and anti-apoptotic activity through modulation of oxidative stress, TGF-β/NF-κB and TGF-β/Smad/p53 signaling pathways.

Nebivolol in oral subacute treatment prevents cardiac post-ischemic dysfunction in rats, but hyperthyroidism reduces this protection: mechanisms involved

Nebivolol could prevent dysfunction in patients suffering myocardial ischemia. However, influence of hyperthyroidism is not known. Consequences and mechanisms of nebivolol treatment were investigated in isolated hearts from euthyroid (EuT) and hyperthyroid (HpT) rats. Rats were orally treated during 1 week with 20 mg/kg/day nebivolol (O-Neb), 30 mg/kg/day atenolol (O-Ate), or not treated (C). Isolated perfused hearts were exposed to global ischemia and reperfusion (I/R) inside a flow calorimeter. Left diastolic ventricular pressure, developed contractile pressure (P), and total heat rate (Ht) were continuously measured, while infarct size was measured after 2-h R. EuT-C and HpT-C hearts developed similarly low post-ischemic contractile recovery and economy (P/Ht). Nebivolol totally prevented dysfunction and reduced infarction size in EuT hearts, but partially improved recovery in HpT rat hearts. Contrarily, oral atenolol totally prevented dysfunction in HpT hearts but partially in EuT hearts. Nebivolol effects were reversed by perfusing L-NAME in both conditions, but partially reduced by aminoguanidine in HpT. However, L-NAME increased P and P/Ht recoveries in EuT-C and HpT-C rat hearts, as well as melatonin. Oral nebivolol prevented post-ischemic dysfunction and infarction in EuT hearts due to adrenergic β1 blockade and activation of iNOS and/or eNOS, but the effect was attenuated in HpT hearts by excessive iNOS-dependent nitrosative pathways.

Ameliorative effect of nebivolol in doxorubicin-induced cardiotoxicity

This study aimed to investigate the potential of nebivolol in preventing doxorubicin-induced cardiotoxicity by targeting the inflammatory, oxidative, and apoptotic pathways. Twenty-eight male rats were randomly divided into four groups, each consisting of seven rats. The control group received standard diets and unrestricted access to water. The rats in the normal saline (N/S) group were administered a 0.9% normal saline solution for two weeks. The doxorubicin group (the "induced group") received doxorubicin at a dosage of 2.5 mg/kg three times per week for two weeks. The nebivolol group received an oral dose of 4 mg/kg of nebivolol for the same duration. The cardiac tissues of rats treated with doxorubicin exhibited increased levels of tumor necrosis factor, interleukin-1, malondialdehyde, and caspase-3 compared to the normal saline control group (p<0.05), along with decreased levels of total antioxidant capacity and Bcl-2. These results show that doxorubicin is harmful to the heart. The administration of nebivolol significantly reduced the cardiotoxic effects induced by doxorubicin, as indicated by a statistically significant decrease in the levels of inflammatory markers, specifically tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) (p<0.05). The nebivolol group exhibited a significant decrease in malondialdehyde levels, which serves as a signal of oxidation, in cardiac tissue compared to the doxorubicin-only group (p<0.05). Additionally, the nebivolol group showed a significant increase in overall antioxidant capacity. Nebivolol dramatically attenuated doxorubicin-induced cardiotoxicity in rats, likely by interfering with oxidative stress, the inflammatory response, and the apoptotic pathway.

Cardio-Protective Role of a Gut Hormone Obestatin: A Narrative Review

Obestatin is a gut hormone composed of 23 amino acids that play a role in protecting the heart. It is synthesized from the same preproghrelin gut hormone gene as another gut hormone. The function and receptor of obestatin remain controversial, despite being present in various organs such as the liver, heart, mammary gland, pancreas, and more. The activity of obestatin is opposite to that of ghrelin, another hormone. The GPR-39 receptor is used by obestatin to exert its effects. Obestatin's cardioprotective role can be attributed to its ability to affect various factors, including adipose tissue, blood pressure regulation, heart, ischemia-reperfusion injury, endothelial cells, and diabetes. Because these factors are related to the cardiovascular system, modifying them via obestatin can provide cardioprotection. Furthermore, ghrelin, its antagonist hormone, regulates cardiovascular health. Diabetes mellitus, hypertension, and ischemia-reperfusion injury can all alter ghrelin/obestatin levels. Obestatin has also been shown to impact other organs, reducing weight and appetite, inhibiting food intake, and increasing adipogenesis. Obestatin has a brief half-life and is quickly degraded by proteases in the blood, liver, and kidneys after entering circulation. This article offers insights into the cardiac function of obestatin.

Nebivolol protects against cyclophosphamide-induced nephrotoxicity through modulation of oxidative stress, inflammation, and apoptosis

The usefulness of cyclophosphamide (CP) in the treatment of multiple human malignancies and immunological diseases is hindered by the danger of developing nephrotoxicity. The toxic metabolites of CP are suggested to be responsible for oxidative stress resulted from the production of reactive oxygen species (ROS) and stimulation of lipid peroxidation. Nebivolol (NEB) is a third-generation selective B1 adrenoceptor antagonist, but it has also various pharmacological properties such as anti-inflammation, anti-apoptotic, and antioxidant activities. Thus, the present study aims to explore the potential protective effect of NEB against CP-induced nephrotoxicity. A cumulative dose of CP (75 mg/kg) was administered to albino rats by intraperitoneal injection. The protective effect of NEB was investigated by co-administration of NEB (10 mg/kg orally daily). Administration of NEB with CP significantly improved renal functions and reduced the oxidative renal changes induced by CP injection. Co-administration of NEB ameliorated apoptosis and inflammatory markers that were markedly exaggerated by CP. Our results indicated that NEB could be used as a protective agent against CP-induced nephrotoxicity.

Protective effects of nebivolol on ovarian ischemia-reperfusion injury in rat

AIM

Ovarian torsion is a common gynecological emergency of reproductive ages, occurring at rates of 2.7-7.4%. This study aimed to evaluate the antioxidant effects of Nebivolol (NEB) and histopathological changes in experimental ischemic (I) and ischemic-reperfusion (I/R) injury in rat ovaries.

METHODS

Forty-eight adult female rats were randomly separated into six groups as group 1 (control) receiving an oral saline solution for 3 days; group 2 (I) that underwent ischemia for 3 h with the application of atraumatic vascular clips; group 3 (I/R); group 4 (I + NEB) receiving 10 mg/kg NEB by oral gavage 30 min prior to the ischemia induction; group 5 (I/R + NEB) receiving 10 mg/kg NEB, and group 6 (control + NEB) receiving oral 10 mg/kg NEB for 3 days before ischemia induction followed by consequent reperfusion. Ovarian tissue damage was scored by histopathological analysis. Ovarian tissue malondialdehyde (MDA) and glutathione (GSH) levels were measured biochemically.

RESULTS

The levels of MDA and tumor necrosis factor-alpha (TNF-α), and TUNEL assay positivity scores increased in the I and I/R groups. GSH levels decreased in all case groups (P < 0.05). The oral administration of NEB (10 mg/kg) to the I- and I/R-groups reduced the levels of MDA and TNF-α and TUNEL assay immunopositivity scores (P < 0.05). GSH levels increased in the treatment groups.

CONCLUSION

The current experimental ovarian torsion study suggests a protective role for NEB against I and I/R injury in rat ovaries. NEB may be a novel agent for decreasing ovarian I/R injury.

Protective effect of nebivolol on doxorubicin-induced cardiotoxicity in rats

INTRODUCTION

The cardiotoxicity of doxorubicin is incompletely understood. We investigated the prophylactic effect of nebivolol on doxorubicin-induced cardiac toxicity.

MATERIAL AND METHODS

Thirty rats were divided into a control group, doxorubicin-treated group and nebivolol + doxorubicin-treated group. The specimens were examined using H + E and Masson's trichrome, caspase 3, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and tumor necrosis factor factor-α (TNF-α). The mean area percentage of collagen fiber content, caspase-3, eNOS, iNOS and TNF-α immunoactivities was measured.

RESULTS

The doxorubicin-treated group showed marked myocyte distortion and fragmentation, congestion and cytoplasmic lysis in most fibers. These changes were less intense in the nebivolol-treated group. The mean area percentage of collagen fiber in the nebivolol-treated group was non-significantly smaller (p = 0.07) than that in the doxorubicin-treated group. The expression of caspase-3 (p = 0.03), eNOS (p ≤ 0.001), iNOS (p < 0.001) and TNF-α (p = 0.003) immunoreactivity was improved in the nebivolol-treated group.

CONCLUSIONS

Nebivolol exerted a significant protective effect from doxorubicin toxicity. The protective effect appears to be mediated mainly through caspase-3, eNOS, iNOS and TNF-α modulation.

Nebivolol Ameliorates Cisplatin-Induced Nephrotoxicity in Rats

Treatment with cisplatin is associated with dose-limiting side effects, mainly nephrotoxicity. On the other hand, nebivolol, a β1 -adrenoceptor antagonist, exhibits vasodilatory and antioxidative properties. This study aimed to determine whether nebivolol possesses a protective effect against cisplatin nephrotoxicity and explore many mechanisms underlying this potential effect. Nephrotoxicity was induced in Wistar rats by a single intraperitoneal injection of cisplatin (6 mg/kg) on day 2. Nebivolol (10 mg/kg) was administered orally for 7 consecutive days. Nebivolol showed a nephroprotective effect as demonstrated by the significant reduction in the elevated levels of serum creatinine and urea as well as renal levels of malondialdehyde, nitric oxide products (nitrite/nitrate), inducible nitric oxide synthase, tumour necrosis factor-alpha, caspase-3, angiotensin II and endothelin-1 with a concurrent increase in renal levels of reduced glutathione and endothelial nitric oxide synthase compared to untreated rats. Histopathological examination confirmed the nephroprotective effect of nebivolol. Pre-treatment with Nω -nitro-L-arginine methyl ester, the non-specific nitric oxide synthase inhibitor, partially altered the protection afforded by nebivolol. In conclusion, nebivolol protects rats against cisplatin-induced nephrotoxicity that is most likely through its antioxidant, anti-inflammatory and antiapoptotic effects as well as by abrogation of the augmented angiotensin II and endothelin-1 levels.

Nebivolol: vasodilator properties and evidence for relevance in treatment of cardiovascular disease

β-adrenergic blocking agents, a pharmacologically diverse class of cardiovascular medications, are recommended as first-line treatment for patients with hypertension and concomitant structural heart disease, and for angina and heart failure. Many within-class differences exist, from pharmacokinetics and pharmacodynamics to ancillary effects, such as intrinsic sympathomimetic activity, antiarrhythmic activity, α-1 adrenergic receptor blockade affinity, and direct vasodilation. Nebivolol is a third-generation, β1 selective, long acting β-blocker, which causes direct vasodilation via endothelium-dependent nitric oxide stimulation. The vasodilatory actions of nebivolol might result in clinical effects with some distinct properties. Differences from other β-blockers might include improvement of endothelial function, enhancement of forward flow in muscular resistance arteries, maintenance of exercise tolerance, and overall improved tolerability, side effect profile, and adherence. Nebivolol has been shown to be a clinically effective β-blocker for treatment as initial or add-on therapy for systemic hypertension, as an antianginal agent, and as therapy for patients with heart failure. These properties position nebivolol as a treatment option for patients with hypertension and/or structural heart disease, although its precise role in the therapeutic armamentarium remains to be clarified.

An update on cardioprotection: a review of the latest adjunctive therapies to limit myocardial infarction size in clinical trials

Acute myocardial infarction (AMI) with subsequent left ventricular dysfunction and heart failure continues to be a major cause of morbidity and mortality in the Western world. Rapid advances in the treatment of AMI, mainly through timely reperfusion, have substantially improved outcomes in patients presenting with acute coronary syndrome and particularly ST-segment elevation myocardial infarction. A vast amount of research, both translational and clinical, has been published on various pharmacological and interventional techniques to prevent myocardial cell death during the time of ischemia and subsequent reperfusion. Several methods of cardioprotection have shown the ability to limit myocardial infarction size in clinical trials. Examples of interventional techniques that have proven beneficial are ischemic post-conditioning and remote ischemic per-conditioning, both of which can reduce infarction size. Lowering core body temperature with cold saline infusion and cooling catheters have also been shown to be effective in certain circumstances. The most promising pharmaceutical cardioprotective agents at this time appear to be adenosine, atrial natriuretic peptide, and cyclosporine, with other potentially effective medications in the pipeline. Additional pre-clinical and clinical research is needed to further investigate newer cardioprotective strategies to continue the current trend of improving outcomes following AMI.

The anti-oxidant and anti-apoptotic effects of nebivolol and zofenopril in a model of cerebral ischemia/reperfusion in rats

The aim of this experiment was to investigate whether nebivolol and zofenopril have protective effects against oxidative damage and apoptosis induced by cerebral ischemia/reperfusion (I/R). There were seven groups of rats, with each containing eight rats. The groups were: the control group, I/R group, I/R plus zofenopril, I/R plus nebivolol, I/R plus nebivolol and zofenopril, zofenopril only and nebivolol only. Cerebral I/R was induced by clamping the bilateral common carotid artery and through hypotension. The rats were sacrificed 1h after ischemia, and histopathological and biochemical analyses were carried out on their brains. The total antioxidant capacity was evaluated by using an automated and colorimetric measurement method developed by Erel. I/R produced a significant increase in the levels of total oxidant status and malondialdehyde levels, the number of caspase-3 immunopositive cells and activities of prolidase and paraoxonase in brain when compared with the control group (p<0.05). A significant decrease in brain total antioxidant capacity and nitric oxide levels were found in I/R group when compared with the control group (p<0.05). Both nebivolol and zofenopril treatment prevented decreasing of the total antioxidant capacity and nitric oxide levels, produced by I/R in the brain (p<0.05). Both nebivolol and zofenopril treatment prevented the total oxidant status, malondialdehyde levels, activities of paraoxonase and prolidase from increasing in brains of rats exposed to I/R (p<0.05). In conclusion, both nebivolol and zofenopril protected rats from ischemia-induced brain injury. The protection may be due to the indirect prevention of oxidative stress and apoptosis.

Roles of the nitric oxide signaling pathway in cardiac ischemic preconditioning against myocardial ischemia-reperfusion injury

Nitric oxide (NO), a vasoactive gas that can freely diffuse into the cell, has many physiological effects in various cell types. Since 1986, numerous studies of ischemic preconditioning against ischemia-reperfusion (I/R) injury have been undertaken and the roles of the NO signaling pathway in cardioprotection have been explored. Many studies have confirmed the effect of NO and that its relative signaling pathway is important for preconditioning of the cardioprotective effect. The NO signaling against I/R injury targeted on the mitochondria is believed to be the end-target for cardioprotection. If the NO signaling pathway is disrupted or inhibited, cardioprotection by preconditioning disappears. During preconditioning, signaling is initiated from the sarcolemmal membrane, and then spread into the cytoplasm via many series of enzymes, including nitric oxide synthase (NOS), the NO-producing enzyme, soluble guanylyl cyclase (sGC), and protein kinase G (PKG). Finally, the signal is transmitted into the mitochondria, where the cardioprotective effect occurs. It is now well established that mitochondria act to protect the heart against I/R injury via the opening of the mitochondrial ATP-sensitive K⁺ channel and the inhibition of mitochondrial permeability transition (MPT). This knowledge may be useful in developing novel strategies for clinical cardioprotection from I/R injury.

Relationship of maximum rate of pressure rise between aorta and left ventricle in pediatric patients. Implication for ventricular-vascular interaction with the potential for noninvasive determination of left ventricular contractility

BACKGROUND

The maximum rate of the ventricular pressure rise (dp/dt(max)) provides a reliable measure of ventricular contractility. However, its estimation requires invasive measurement of left ventricular (LV) pressure, limiting its bedside clinical applicability. In the present study, 2 hypotheses were tested: (1)that the ratio of dp/dt(max) between the aorta (Ao) and LV is consistent among patients despite marked differences in underlying cardiac disease, contractile state and heart rate when vascular mechanical and loading properties are taken into account, and (2)that using such a relationship, LV dp/dt(max) can be estimated from Ao dp/dt(max), potentially providing a method of noninvasive determination of LV contractility.

METHODS AND RESULTS

Data from 30 control children and 45 pediatric patients with various cardiovascular diseases revealed that the characteristic impedance (Zc) and mean arterial pressure were significant determinants of the Ao-LV dp/dt(max) relationship in both control and disease groups. LV dp/dt(max) estimated using the regression obtained in the control children (Ao dp/dt(max/)LV dp/dt(max) = 0.64+1.45*10(-4)*Zc-3.73*10(-3)*MAP, r=0.87) correlated well with the measured LV dp/dt(max) in the disease group, including measurements taken after dobutamine and atrial pacing (r=0.89).

CONCLUSIONS

Ao dp/dt(max) and LV dp/dt(max) are closely correlated through the vascular loading properties and LV dp/dt(max) can be derived from Ao dp/dt(max), which has potential as a noninvasive method of determining LV contractility.

Nitric oxide mechanisms of nebivolol

β-blockers are among the most widely used drugs in the prevention and treatment of cardiovascular disease, although they are associated with increased peripheral resistance. Third-generation β-blockers avoid this adverse effect by inducing vasodilation through different mechanisms. In particular, nebivolol, a highly selective blocker of β1-adrenergic receptors, is the only β-blocker known to induce vascular production of nitric oxide, the main endothelial vasodilator. The specific mechanism of nebivolol is particularly relevant in hypertension, where nitric oxide dysfunction occurs. Indeed, nebivolol is able to reverse endothelial dysfunction. Nebivolol induces nitric oxide production via activation of β3-adrenergic receptors, which can explain the good metabolic profile observed after treatment with this drug. Moreover, nebivolol can also stimulate the β3-adrenergic receptor-mediated production of nitric oxide in the heart, and this stimulation can result in a greater protection against heart failure. In conclusion, nebivolol has a unique profile among antihypertensive drugs, adding to a very high selectivity against β1 adrenergic receptors, and an agonist action on β3 receptors and nitric oxide (NO), which has led to clinically significant improvements in hypertensive patients.

Elevation of plasma granzyme B levels after acute myocardial infarction

BACKGROUND

Apoptosis is reported to play an important role in left ventricular (LV) remodeling after acute myocardial infarction (AMI). Granzyme B is a member of the serine esterase family, which has an important role in cellular apoptosis and extracellular matrix degradation.

METHODS AND RESULTS

Peripheral blood samples were obtained from 33 patients with a first-onset AMI treated by percutaneous coronary intervention (mean age: 61.4+/-8.7 years old) on days 1, 7 and 14 after onset. Plasma levels of tumor necrosis factor (TNF)-alpha, a soluble form of the Fas ligand (sFasL), and granzyme B were measured. TIMI grade 3 recanalization was accomplished in all patients within 12 h after onset. The LV end-diastolic volume index (LVEDVI) was calculated on day 1 and at 6 months after onset. Plasma levels of TNF-alpha, sFasL and granzyme B increased significantly on days 7 and 14 after onset of AMI. Stepwise multivariate regression analysis showed that the plasma granzyme B level on day 14 is a significant explanatory variable for changes in the LVEDVI.

CONCLUSIONS

Plasma levels of granzyme B increased after AMI, which might be an important factor in the progression of late LV remodeling after AMI.