Moderate calorie restriction improves cardiac remodeling and diastolic dysfunction in the Dahl-SS rat

Area of Science:

• Cardiovascular Research
• Metabolic Disease
• Nutritional Science

Background:

• Caloric restriction (CR) is linked to longevity and reduced chronic disease in animal models.
• Human studies show CR improves blood pressure, inflammation, and cardiac function, but diet composition confounds mechanisms.
• The Dahl salt-sensitive rat model develops hypertension-associated diastolic dysfunction, making it suitable for studying CR's impact on heart failure.

Purpose of the Study:

• To investigate the effects of moderate caloric restriction on decompensated pressure-overload hypertrophy in Dahl salt-sensitive rats.
• To determine if CR mitigates heart failure progression independently of salt intake.

Main Methods:

• Male Dahl salt-sensitive rats were fed either a low-salt or high-salt diet to induce heart failure.
• A subset of high-salt rats received 15% caloric restriction while maintaining salt load.
• Echocardiography assessed cardiac function and geometry; various physiological and biochemical markers were measured post-study.

Main Results:

• High-salt diet induced features of decompensated pressure-overload hypertrophy.
• Caloric restriction in high-salt rats significantly reduced blood pressure, delayed cachexia, and lowered hyperlipidemia.
• CR improved diastolic function, reduced organ weights (heart, kidney, lung), decreased inflammation (IL-6, TNF-alpha), and lessened cardiac oxidative damage.

Conclusions:

• Moderate caloric restriction, independent of salt intake, effectively reduced pathogenesis in a rat model of decompensated pressure-overload hypertrophy.
• CR demonstrated significant benefits in mitigating heart failure progression and associated complications.
• These findings highlight CR as a potential therapeutic strategy for managing heart failure.