Influence of intermittent fasting on myocardial infarction-induced cardiac remodeling

Abstract

Background Information on the role of intermittent fasting (IF) on pathologic cardiac remodeling is scarce. We compared the effects of IF before and after myocardial infarction (MI) on rat cardiac remodeling and survival. Methods Wistar rats were intermittently fasted (food available every other day) or fed ad libitum for 12 weeks and then divided into three groups: AL – fed ad libitum; AL/IF - fed AL before MI and IF after MI; and IF – fed IF before and after MI. Echocardiogram was performed before MI and 2 and 12 weeks after surgery. Isolated hearts were evaluated in Langendorff preparations. Results Before surgery, body weight (BW) was lower in IF than AL. Final BW was lower in AL/IF and IF than AL. Perioperative mortality did not change between AL (31.3%) and IF (27.3%). Total mortality was lower in IF than AL. Before surgery, echocardiographic parameters did not differ between groups. Two weeks after surgery, MI size did not differ between groups. Twelve weeks after MI, left ventricular (LV) diastolic posterior wall thickness was lower in AL/IF and IF than AL. The percentage of variation of echocardiographic parameters between twelve and two weeks showed that MI size decreased in all groups and the reduction was higher in IF than AL/IF. In Langendorff preparations, LV volume at zero end-diastolic pressure (V0; AL: 0.41 ± 0.05; AL/IF: 0.34 ± 0.06; IF: 0.28 ± 0.05 mL) and at 25 mmHg end-diastolic pressure (V25; AL: 0.61 ± 0.05; AL/IF: 0.54 ± 0.07; IF: 0.44 ± 0.06 mL) was lower in AL/IF and IF than AL and V25 was lower in IF than AL/IF. V0/BW ratio was lower in IF than AL and LV weight/V0 ratio was higher in IF than AL. Myocyte diameter was lower in AL/IF and IF than AL (AL: 17.3 ± 1.70; AL/IF: 15.1 ± 2.21; IF: 13.4 ± 1.49 μm). Myocardial hydroxyproline concentration and gene expression of ANP, Serca 2a, and α- and β-myosin heavy chain did not differ between groups. Conclusion Intermittent fasting initiated before or after MI reduces myocyte hypertrophy and LV dilation. Myocardial fibrosis and fetal gene expression are not modulated by feeding regimens. Benefit is more evident when intermittent fasting is initiated before rather than after MI.

Dieta Intermitente Atenua a Remodelação Cardíaca Causada pelo Exercício Físico

“…However, it was not possible to verify association between intermittent fasting and changes in MAPK protein expression. In a previous study, 39 intermittent fasting attenuated cardiac hypertrophy and ventricular dilation in infarcted rats, although it did not alter the gene expression of fetal peptides.…”

Modulatory Effect of Intermittent Fasting on Adipose Tissue Inflammation: Amelioration of Cardiovascular Dysfunction in Early Metabolic Impairment

“…A recent study examined the effect of alternate day fasting on cardiac remodeling post-myocardial infarction (MI) in rats. While IF improved cardiac function and reduced left ventricular dilation, none of the fibrosis gene markers examined appeared to have been affected (Okoshi et al, 2019). Another study showed that alternate day fasting promoted cardiomyocyte survival post-MI in rats by increasing the expression of antiapoptotic and angiogenic factors (Katare et al, 2009).…”

Effects of Bergamot Polyphenols on Mitochondrial Dysfunction and Sarcoplasmic Reticulum Stress in Diabetic Cardiomyopathy

“…A high-fat diet during gestation in several species causes deleterious effects in newborns; in particular, altered gene expression, abnormalities in the functions of antioxidant enzymes, the increased possibility of developing atherogenesis, and damage to the cardiovascular system [ 139 ]. The reduction of fatty acids intake generally has several benefits, such as a reduction in body weight, and cholesterol and triglyceride levels, and an improvement in the functioning of the myocardium [ 140 , 141 ]. Polyphenols are bioactive chemical compounds synthesized by plants that are mainly found in fruits and vegetables, where they are responsible for color, flavor, and many pharmacological activities.…”