Nebivolol reduces experimentally induced warm renal ischemia reperfusion injury in rats

Cannabinoid receptor 2 (CB2) agonists and L-arginine ameliorate diabetic nephropathy in rats by suppressing inflammation and fibrosis through NF-κβ pathway

Diabetic nephropathy (DN) is a condition that leads to end-stage chronic kidney disease characterized by inflammation and a deficiency of nitric oxide (NO). Cannabinoid receptor (CB2) activation by specific agonist reduces nuclear factor kappa beta (NF-κβ) expression. Beta caryophyllene (BCP), a natural CB2 receptor activator, protects kidney function in several diseases. L-Arginine (LA) modulates several physiological processes by donating nitric oxide (NO). Hence, we tested a novel BCP-LA combination to treat DN and investigated its molecular mechanisms. BCP, LA, and combinations of both were evaluated in LPS-induced RAW 264.7 macrophage inflammation as well as in streptozotocin (55 mg/kg)-induced diabetes in SD rats. Diabetic rats were administered 200 mg/kg of BCP, 100 mg/kg of LA, and combination of both orally for 28 days. Biochemical markers and inflammatory cytokines were assessed in plasma; also, kidney tissue was examined for renal oxidative stress injury, NF-κβ expression, and histology. After 28 days of treatment, BCP and LA combination significantly lowered plasma glucose levels than the disease control group. BCP and LA also normalized renal markers and oxidative stress of diabetic rats. Plasma and RAW macrophage cell lines showed reduced levels of IL-6 and TNF-α (P < 0.001). Histopathological evaluations revealed that BCP and LA together decreased renal fibrosis and collagen deposition also improved nephrotic indices. Meanwhile, the effect of BCP and LA together significantly reduced the NF-κβ (P < 0.01) against diabetic rats. These results indicate that the innovative regimen BCP with LA may be a therapeutic treatment for DN, as it protects kidney tissue from diabetes via NF-κβ inhibition.

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.

The β1 Adrenergic Blocker Nebivolol Ameliorates Development of Endotoxic Acute Lung Injury

Acute lung injury (ALI) is a disease, with no effective treatment, which might result in death. Formations of excessive inflammation and oxidative stress are responsible for the pathophysiology of ALI. Nebivolol (NBL), a third-generation selective β1 adrenoceptor antagonist, has protective pharmacological properties, such as anti-inflammatory, anti-apoptotic, and antioxidant functions. Consequently, we sought to assess the efficacy of NBL on a lipopolysaccharide (LPS)-induced ALI model via intercellular adhesion molecule-1 (ICAM-1) expression and the tissue inhibitor of metalloproteinases-1 (TIMP-1)/matrix metalloproteinases-2 (MMP-2) signaling. Thirty-two rats were split into four categories: control, LPS (5 mg/kg, intraperitoneally [IP], single dose), LPS (5 mg/kg, IP, one dosage 30 min after last NBL treatment), + NBL (10 mg/kg oral gavage for three days), and NBL (10 mg/kg oral gavage for three days). Six hours after the administration of LPS, the lung tissues of the rats were removed for histopathological, biochemical, gene expression, and immunohistochemical analyses. Oxidative stress markers such as total oxidant status and oxidative stress index levels, leukocyte transendothelial migration markers such as MMP-2, TIMP-1, and ICAM-1 expressions in the case of inflammation, and caspase-3 as an apoptotic marker, significantly increased in the LPS group. NBL therapy reversed all these changes. The results of this study suggest that NBL has utility as a potential therapeutic agent to dampen inflammation in other lung and tissue injury models.

Treatment with β-blocker nebivolol ameliorates oxidative stress and endothelial dysfunction in tenofovir-induced nephrotoxicity in rats

Background

Tenofovir disoproxil fumarate (TDF), a widely prescribed component in antiretroviral regimens, has been associated with nephrotoxicity. Nebivolol is a third generation selective β-1 adrenergic receptor blocker and may protect renal structure and function through the suppression of oxidative stress and enhancement of nitric oxide (NO) synthesis. We aimed to investigate whether nebivolol could be an effective therapeutic strategy to mitigate tenofovir-induced nephrotoxicity.

Methods

We allocated Wistar rats to four groups: control (C), received a standard diet for 30 days; NBV, received a standard diet for 30 days added with nebivolol (100 mg/kg food) in the last 15 days; TDF, received a standard diet added with tenofovir (300 mg/kg food) for 30 days; and TDF+NBV, received a standard diet added with tenofovir for 30 days and nebivolol in the last 15 days.

Results

Long-term exposure to tenofovir led to impaired renal function, induced hypertension, endothelial dysfunction and oxidative stress. Nebivolol treatment partially recovered glomerular filtration rate, improved renal injury, normalized blood pressure and attenuated renal vasoconstriction. Administration of nebivolol contributed to reductions in asymmetric dimethylarginine (ADMA) levels as well as increases in endothelial nitric oxide sintase (eNOS) accompanied by renin-angiotensin-aldosterone system downregulation and decreases in macrophage and T-cells infiltrate. Furthermore, nebivolol was responsible for the maintenance of the adequate balance of thiobarbituric acid reactive substances (TBARS) and glutathione (GSH) levels and it was associated with reductions in NADPH oxidase (NOX) subunits.

Conclusion

Nebivolol holds multifaceted actions that promote an advantageous option to slow the progression of kidney injury in tenofovir-induced nephrotoxicity.

The pretreatment of rats with nebivolol ameliorates bladder contractile dysfunction caused by ischemia-reperfusion injury

OBJECTIVE

The present study aimed to investigate the protective effect of nebivolol in the bladder isolated from rats exposed to ischemia-reperfusion (IR) injury.

METHODS

Sprague-Dawley rats were divided into control, IR, and nebivolol+IR groups. In the nebivolol+IR group, nebivolol was administered (0.4 mg/kg, subcutaneous) in rats prior to IR insult. At the end of the experimental protocol, the urinary bladder was rapidly isolated and bladder strips were mounted in an organ bath. After the equilibration period, potassium chloride (KCl, 20-100 mM) or carbachol (0.01-10 μM) was cumulatively added to the organ bath to generate cumulative concentration-response curves (CCRCs). Oxidative stress and interleukin 6 (IL-6) levels were also evaluated in the bladder tissue.

RESULTS

The CCRCs of KCl and carbachol were significantly reduced in the IR group compared to those of the control, and this inhibition was reversed by the pretreatment of rats with nebivolol (P < .05). The IR group's total antioxidant status was significantly lower with a concomitant increase in IL-6 levels than that of the control and nebivolol+IR groups (P < .05).

CONCLUSIONS

The present study indicates that pretreatment of rats with nebivolol (0.4 mg/kg) could improve bladder contractile dysfunction caused by IR injury through suppression of increased oxidative stress and IL-6 levels.

Protective Effects of Vasodilatory Βeta-Blockers Carvedilol and Nebivolol against Glycerol Model of Rhabdomyolysis-Induced Acute Renal Failure in Rats

BACKGROUND

Rhabdomyolysis (RM)-induced acute renal failure (ARF) accounts for about 10-40% of all cases of ARF.

AIM

The present study investigated the possible protective effect of two nitric oxides (NO)-releasing third generation β-blockers, carvedilol (Carv) and nebivolol (Nebi), against RM-mimicking glycerol (Gly)-induced ARF in rats.

MATERIAL AND METHODS

After 24 h dehydration, rats received a single dose of 50% Gly (8 ml/kg, im). They were treated with vehicle, Carv (2.5 mg/kg/day, po) or Nebi (10 mg/kg, po) for 3 successive days starting from an hour prior to Gly injection. Evaluation of blood pressure and locomotor activity was performed during the experiment. 72 h following Gly administration, total protein in the urine, serum levels of creatinine, blood urea nitrogen, sodium and potassium as well as the renal contents of malondialdehyde, reduced glutathione and NO were assessed, together with a histopathological examination of renal tissues.

RESULTS

Carv and Nebi attenuated Gly-induced renal dysfunction and histopathological alterations. They decreased the Gly-induced oxidative stress and increased renal NO concentration. Restoration of normal blood pressure and improvement of locomotor activity were also observed.

CONCLUSION

The results clearly demonstrate protective effects of Carv and Nebi against renal damage involved in RM-induced ARF and suggest a role of their antioxidant and NO-releasing properties.

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.

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.

Inflammation and therapy for hypertension

It is currently accepted that hypertension, atherosclerosis, and diabetes are disorders with subtle or overt activation of inflammatory mediators. Therefore, it has become increasingly important to ascertain whether current antihypertensive drug families have proinflammatory or anti-inflammatory actions that modify the outcomes of their hemodynamic effects on blood pressure. We review the current state of knowledge about the effects of the major classes of available antihypertensive agents on inflammation and speculate on the possible contribution of these effects to observations in clinical trials. We suggest that a strategy of drug development specifically addressing inflammation in hypertension may provide increased benefit in terms of target organ damage, and we describe some examples of these promising developments.

Time dependent bladder apoptosis induced by acute bladder outlet obstruction and subsequent emptying is associated with decreased MnSOD expression and Bcl-2/Bax ratio

Ischemia/reperfusion (I/R) injury-induced oxidative stress plays an important role in the functional impairment of the bladder following acute bladder outlet obstruction (BOO) via induction of apoptosis. The purpose of this study was to investigate the time course of the bladder apoptosis, and apoptosis related molecular changes in the early stage of acute BOO. Twelve-week-old male Sprague Dawley rats were divided into control, acute BOO only (I), and acute BOO plus subsequent emptying (I/R) for 30, 60, 120 min, 3 days and 2 weeks. We examined the extent of bladder apoptosis, expression of Mn-superoxide dismutase (Mn-SOD), Bcl-2, Bax, caspase 3 and poly (ADP-ribose) (PAR) in the bladder. Bladder apoptosis was significantly increased in the I/R group at 30, 60, and 120 min following bladder emptying. BOO plus subsequent emptying for 30, 60, 120 min showed significant decrease in MnSOD and Bcl-2 expression, and significant increase in caspase 3, Bax expression, and amounts of PAR. These results indicate that bladder apoptosis, induced by acute BOO and subsequent emptying, is associated with decreased MnSOD expression, increased PARP activity and imbalance in apoptosis pathways.