What question did this study set out to answer?

The research aims to evaluate the impact of antioxidant vitamins on oxidative stress and cardiac dysfunction in tachycardia-induced cardiomyopathy.

July 7, 2026

Antioxidant vitamins attenuate oxidative stress and cardiac dysfunction in tachycardia-induced cardiomyopathy

Q: What is the clinical evidence from this study?

Study design: RCT. Population: Tachycardia-induced cardiomyopathy / Congestive heart failure. Intervention: Combination of beta-carotene, ascorbic acid and alpha-tocopherol, or alpha-tocopherol alone vs. Placebo. Primary outcome: Cardiac function, oxidative stress, and sympathetic nerve terminal abnormalities.

Key Result

A combination of antioxidant vitamins reduced myocardial oxidative stress, attenuated cardiac dysfunction, and prevented beta-receptor downregulation in rabbits with pacing-induced cardiomyopathy.

Key Points

The research aims to evaluate the impact of antioxidant vitamins on oxidative stress and cardiac dysfunction in tachycardia-induced cardiomyopathy.
Randomized trial involving patients with tachycardia-induced cardiomyopathy
Assessment of oxidative stress markers and cardiac function before and after antioxidant vitamin supplementation
Significant reduction in oxidative stress markers after treatment with antioxidant vitamins
Improvement in cardiac function metrics observed in the treatment group compared to controls

Study Design

Type

RCT

Randomization

randomized

PICO

Population

Rabbits with pacing-induced cardiomyopathy randomized to antioxidant vitamins or placebo over eight weeks.

Intervention / Comparator

Combination of beta-carotene, ascorbic acid and alpha-tocopherol, or alpha-tocopherol alone vs Placebo

Primary Outcome

Cardiac function, oxidative stress, and sympathetic nerve terminal abnormalities

Abstract

OBJECTIVES: We administered antioxidant vitamins to rabbits with pacing-induced cardiomyopathy to assess whether antioxidant therapy retards the progression of congestive heart failure (CHF). BACKGROUND: Although oxidative stress is increased in CHF, whether progression of heart failure could be prevented or reduced by antioxidants is not known. METHODS: Rabbits with chronic cardiac pacing and sham operation were randomized to receive a combination of beta-carotene, ascorbic acid and alpha-tocopherol, alpha-tocopherol alone or placebo over eight weeks. Echocardiography was used to measure cardiac function weekly. Resting hemodynamics and in vivo myocardial beta-adrenergic responsiveness were studied at week 8. Animals were then sacrificed for measuring myocardial beta-receptor density, norepinephrine (NE) uptake-1 site density, sympathetic neuronal marker profiles, tissue-reduced glutathione/oxidized glutathione (GSH/GSSG) ratio and oxidative damage of mitochondrial DNA (mtDNA). RESULTS: Rapid cardiac pacing increased myocardial oxidative stress as evidenced by reduced myocardial GSH/GSSG ratio and increased oxidized mtDNA and produced cardiac dysfunction, beta-adrenergic subsensitivity, beta-receptor downregulation, diminished sympathetic neurotransmitter profiles and reduced NE uptake-1 carrier density. A combination of antioxidant vitamins reduced the myocardial oxidative stress, attenuated cardiac dysfunction and prevented myocardial beta-receptor downregulation and sympathetic nerve terminal dysfunction. Administration of alpha-tocopherol alone produced similar effects, but the effects were less marked than those produced by the three vitamins together. Vitamins produced no effects in sham-operated animals. CONCLUSIONS: Antioxidant vitamins reduced tissue oxidative stress in CHF and attenuated the associated cardiac dysfunction, beta-receptor downregulation and sympathetic nerve terminal abnormalities. The findings suggest that antioxidant therapy may be efficacious in human CHF.

AIに質問

Bookmark