Nebivolol to attenuate the effects of hyper-homocysteinaemia in rats.

OBJECTIVE: This study investigated the prophylactic effect of nebivolol against hyper-homocysteinaemia (hHcy) induced oxidative stress in brain, heart, liver and kidney tissues and histomorphometric changes in the thoracic aorta. METHODS: Twenty-four adult male Wistar rats were divided into a control, nebivolol, hHcy and nebivolol+hHcy group. hHcy was induced by oral administration of L-methionine (1 g/kg/day) for 28 days. 10 mg/kg/day nebivolol was administered orally for 28 days. Malondialdehyde (MDA) and glutathione (GSH) levels and catalase (CAT) and superoxide dismutase (SOD) activities in the tissues were determined. The total cross-sectional area (TCSA), luminal cross-sectional area (LCSA) and intima-media thickness (IMT) were measured in the thoracic aorta. RESULTS: Homocysteine (Hcy) levels were lower in the nebivolol+hHcy group than in the hHcy group. Nebivolol treatment significantly decreased high MDA levels in the brain, heart and liver tissues. The level of GSH was higher in the brain, heart and kidney tissues of the nebivolol+hHcy group (P<0.001). The activity of CAT increased only in the kidney tissue of the nebivolol+hHcy group (P<0.01), and the activity of SOD was significantly increased in all the tissues in this group. Increased TCSA and IMT in the nebivolol+hHcy group were significantly decreased after nebivolol administration. The LCSA was significantly higher in the hHcy group than the control group, probably due to outward vascular remodelling. CONCLUSION: Nebivolol treatment may be useful in different clinical scenarios where hHcy affects physiopathological pathways.

The usefulness of carvedilol and nebivolol in preventing contrast nephropathy in rats.

BACKGROUND: Oxidative stress and vasoconstriction appear to be important components of contrast nephropathy (CN) pathogenesis, and both carvedilol and nebivolol are known to have vasodilatory and antioxidant effects. AIMS: This study aimed to investigate whether carvedilol and nebivolol play preventive roles against developing CN and to compare the effects of each. MATERIALS AND METHODS: Wistar albino rats were divided into control (C, n = 6), contrast material (CM, n = 6), carvedilol (CV, n = 7), carvedilol + contrast material (CV + CM, n = 7), nebivolol (N, n = 7), and nebivolol + contrast (N + CM, n = 7) groups. Following 3 days of dehydration, 6 mL/kg diatrizoate was administered to each rat. Carvedilol was given at a dose of 2 mg/kg and nebivolol at a dose of 1 mg/kg by way of oral gavage. After scarification, total antioxidant capacity (TAC), malondialdehyde (MDA), and superoxide dismutase (SOD) were studied in renal tissue. Histopathological findings were graded as mild (+), moderate (++), and severe (+++). RESULTS AND DISCUSSION: Most of the histopathological findings and MDA levels were significantly higher in the CM group than that in the C, CVCM, and NVCM groups, whereas there was no significant difference between the C, CVCM and NVCM groups. TAC level in the CM group was significantly lower than in all other groups. There was no difference in SOD among groups. CONCLUSIONS: Carvedilol and nebivolol both prevent development of nephropathy related to CMs by decreasing oxidative stress. Neither is superior to the other.

A clinical study about contrast nephropathy: risk factors and the role of beta blockers.

OBJECTIVE: There is still a group of patient that have unpredictable risk for the development of contrast nephropathy (CN). There is also an effort to find more effficient strategies to prevent CN. Carvedilol, metoprolol and nebivolol seem to have theoretical potentials for the prevention of CN. In this study, we aimed to investigate their effects on the prevention of CN. We also aimed to define the risk factors associated with the development of CN in our study group. METHODS: In this prospective, cross-sectional study, the patients were divided into four groups according to whether they were taking 25 mg/day carvedilol (n:56), 5 mg/day nebivolol (n:60), 50 mg/day metoprolol (n:68) or none (n:63). We made analysis to determine the agents' efficiency on the prevention of CN. We also performed multiple logistic regression analysis including all groups to define the risk factors associated with CN. RESULTS: The incidents of CN were the lowest in the carvedilol group (4%) while the worst performance occurred in those taking metoprolol (10%). The difference between the groups in terms of the development of CN did not reach statistical significance (p>0.05). Multiple logistic regression analysis showed age (p=0.003), higher triglyceride levels (p=0.011) and family history of coronary artery disease (p=0.038) to be the predictors of CN. CONCLUSION: In this study, we didn't find any relation between the development of CN and carvedilol, metoprolol or nebivolol usage. We found age, higher levels of triglyceride and family history of coronary artery disease to be risk factors for predicting CN.

Spontaneous retrograde dissection of the ascending aorta in a patient with a bicuspid aortic valve.

Bicuspid aortic valve (BAV) is a congenital anomaly associated with structural weakness of the aortic wall. Sudden onset of symptoms in patients with BAV, such as sudden severe back pain, and pulse inequality between the extremities or tension disparity should alert clinicians to acute aortic syndromes, as they require prompt diagnosis and management. Retrograde aortic dissection, which is a rare form of acute aortic syndrome, is an uncommon life-threatening entity and may produce atypical computed tomography (CT) or magnetic resonance imaging findings, leading to difficulty in diagnosis. We report on a 51-year-old male patient with BAV and spontaneous retrograde ascending aortic dissection. CT findings were confusing and the diagnosis was made via transoesophageal echocardiography. After the diagnosis, the patient was treated with a modified Bentall procedure. He did not have any complications and was stable four months after the operation.