Caloric restriction reduces the magnitude of many age-related changes in rodent. Cardiac function is altered with senescence in mice, rats, and healthy humans. We examined the effects of life-long caloric restriction on diastolic and systolic cardiac function on situ using Doppler techniques in ad libitum-fed 30- to 32-month-old (AL) and calorically restricted (CR) 32- to 35-month-old female B6D2-F1 hybrid mice. The heart weight to body weight ratio was similar in AL (5.74 ± .24 mg/g) and CR (5.68 ± .20 mg/g) mice. Two systolic functional parameters known to decrease with age in both humans and mice, peak aortic velocity and aortic acceleration, wire unchanged by CR compared to AL. In contrast diastolic function was altered by calorie restriction. Although left ventricular peak early filing velocity (E) was not different between CR and AL, peak atrial filling velocity (A) war 50% lower in CR compared to A L (p < .001). The ratio of early diastolic filling to atrial filling (E/A ratio) was 64% higher in the CR (2.74 ±.31) than the AL (1.55 ± .07; p = .004). The fraction of ventricular filling due to atrial systole, the atrial filling fraction, was also reduced in CR (.21 ± .04) compared to AL (.36 ± .02; p = .007). These changes occurred in CR without alteration in E deceleration time, which is consistent with improved diastolic function in CR. Through mechanism that remain unknown, lifelong caloric restriction may prevent the age-related impairments in late diastolic function but does not alter the impairments in systolic or early diastolic cardiac function.
|Original language||English (US)|
|Journal||Journals of Gerontology - Series A Biological Sciences and Medical Sciences|
|State||Published - 1997|
ASJC Scopus subject areas
- Geriatrics and Gerontology