The effects of advanced age on electrocardiographic parameters, lipid profile and redox balance in male rats: role of long-term cinnamon consumption

Oxidative stress damages biological molecules and plays a role in aging-related cardiovascular diseases. Cinnamomum zeylanicum is a major source of antioxidants that may work against age-related cardiovascular changes.

This study aimed to assess the changes in electrocardiography and lipid profile as well as indicators of the oxidant-antioxidant system with advanced age in rats. Also, the possible beneficial effect of cinnamon on these parameters has been investigated.

In this experimental study, thirty male Sprague-Dawley rats were randomly assigned to five groups. The control groups of 12, and 20 months received a normal chow diet, while the investigation group was given a control diet mixed with cinnamon powder (1% of the diet). Also, a control group of 3-month-old rats was considered for assessment of age effects. Systolic blood pressure (SBP), ECG, serum lipid profiles, and heart oxidative stress markers were compared in different groups at the end of the study.

Systolic BP, serum cholesterol, HDL and LDL-cholesterol, the heart level of malondialdehyde (MDA) and nitric oxide metabolites (NOx), the ECG parameters including QRS duration, PR, Tpeak-Tend, and QT interval, as well as QTc increased significantly in older rats (20 months vs 3 months). Cinnamon consumption restored MDA levels, QRS duration, and Tpeak-Tend interval in aging hearts. Whereas, neither aging nor cinnamon consumption could affect SOD activity.

The results demonstrated that aging is associated with ECG alteration, oxidative stress, and an increase in TC, LDL, and HDL cholesterol. Cinnamon improved electrical heart activity in aged rats (20 months) by restoration of QRS duration and Tpeak-Tend interval as well as amelioration of heart oxidative stress. Altogether, cinnamon supplementation has a cardioprotective effects during aging in rats.