Intense Caloric Restriction from Birth Prevents Cardiovascular Aging in Rats

Area of Science:

• Aging Research
• Cardiovascular Physiology
• Metabolic Health

Background:

• Previous studies showed 50% caloric restriction (CR) from birth improves cardiometabolic risk factors in young rats.
• The long-term effects of sustained CR on cardiac health and metabolism in aging animals remain less understood.

Purpose of the Study:

• To investigate the consequences of a 50% CR initiated from birth on cardiometabolic risk factors, cardiac function, and cellular health in middle-aged rats.
• To assess the impact of CR on ventricular arrhythmia, fibrillation, and cardiac intracellular proteins related to redox status and cell survival.

Main Methods:

• Rats were maintained on either an Ad Libitum (AL18) or 50% CR (CR18) diet from birth to 18 months.
• Evaluated cardiometabolic risk factors through metabolic rate, blood pressure, glucose/insulin tolerance tests, and biochemical analyses.
• Assessed cardiac function, histology, redox status, and protein expression via western blot.

Main Results:

• CR18 rats exhibited reduced cardiometabolic risk factors compared to AL18 rats at 18 months.
• The CR18 group demonstrated a ~50% increase in cardiac contractility and relaxation.
• CR18 rats showed significantly lower incidence of ventricular arrhythmia/fibrillation, reduced cardiomyocyte diameter, and decreased cardiac fibrosis.

Conclusions:

• A 50% caloric restriction initiated from birth confers substantial metabolic and cardiac benefits in middle-aged rats.
• CR from birth demonstrates potent antiaging effects on the cardiovascular system, improving function and reducing pathology.
• These findings highlight the long-term protective role of early-life sustained caloric restriction against age-related decline.