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Nebivolol: a multifaceted antioxidant and cardioprotectant in hypertensive heart disease

M Usman Khan1, Wenyuan Zhao, Tieqiang Zhao

  • 1*Division of Cardiovascular Diseases, Department of Medicine; †Department of Obstetrics & Gynecology; and ‡Division of Endocrinology, Department of Medicine, University of Tennessee Health Science Center, Memphis, TN.

Journal of Cardiovascular Pharmacology
|August 8, 2013
PubMed

Insights

Nebivolol, a novel antioxidant, protects against hypertensive heart disease by increasing zinc and nitric oxide levels, reducing calcium overload and oxidative stress, and preventing myocyte necrosis and scarring.

Area of Science:

  • Cardiovascular Research
  • Pharmacology
  • Oxidative Stress Biology

Background:

  • Hypertensive heart disease (HHD) is characterized by cardiomyocyte necrosis and scarring.
  • Oxidative stress, driven by calcium overload ([Ca]i and [Ca]m), underlies myocyte necrosis in HHD.
  • Current treatments lack comprehensive antioxidant strategies.

Purpose of the Study:

  • To investigate the antioxidant and cardioprotective effects of nebivolol (Neb) compared to atenolol (Aten) in a rat model of HHD.
  • To elucidate the mechanisms underlying nebivolol's potential cardioprotection, focusing on nitric oxide (NO) and zinc signaling.
  • To evaluate nebivolol's impact on oxidative stress markers and cardiac tissue damage.

Main Methods:

  • Utilized a rat model of hypertensive heart disease (HHD) induced by aldosterone/salt treatment (ALDOST).
  • Administered nebivolol (Neb) and atenolol (Aten) to HHD rats and assessed various biochemical and histological parameters.
  • Measured intracellular and mitochondrial calcium ([Ca]i, [Ca]m), cytosolic free zinc ([Zn]i), nitric oxide (NO) generation, and oxidative stress markers (H2O2, 8-isoprostane).

Main Results:

  • Nebivolol, but not atenolol, significantly increased endothelial nitric oxide synthase activation, NO generation, and cytosolic free zinc ([Zn]i).
  • Nebivolol cotreatment led to a marked reduction in cytosolic and mitochondrial calcium ([Ca]i, [Ca]m) overload.
  • Nebivolol attenuated mitochondrial H2O2 production and lipid peroxidation, resulting in reduced microscopic scarring and collagen volume fraction in cardiac tissue.

Conclusions:

  • Nebivolol exhibits multifaceted antioxidant properties beyond beta-blockade, acting as a potent cardioprotective agent in hypertensive heart disease.
  • The unique mechanism involves enhanced nitric oxide and zinc signaling, which counteracts calcium overload and oxidative stress.
  • Nebivolol represents a promising therapeutic strategy for preventing cardiomyocyte necrosis and structural damage in HHD.

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