Date Published: April 4, 2018
Author(s): Dina Sibouakaz, Khira Othmani-Mecif, Amirouche Fernane, Abdennour Taghlit, Yasmina Benazzoug.
Early weight gain induced by high-fat diet has been identified as a predictor for cardiac disease, one of the most serious public health problems. Our goal is to study the influence of a HFD on biochemical, oxidant stress parameters, and the cardiac ultrastructure in both male and female prepubertal models. Experiments were carried on 24 prepubertal New Zealand white rabbits, randomly assigned to male and female control (MC and FC, resp.) or HFD (MHFD and FHFD, resp.) groups (n = 6) for 3 months. Body and heart weights and some biochemical and oxidative stress parameters such as lipids, calcium, CKMB, MDA, uric acid, ascorbic acid, and AOA are evaluated in plasma and the left ventricle. Under HFD effect, plasma parameters, such as lipids (TL, PL, and LDL-C), MDA, and CK-MB, increase more significantly in male than in female groups, when AA decreases. Some cardiac parameters such as TG and UA increase, when AA and AOA decrease; these variations are more significant in FHFD. In both male and female rabbits, HFD caused changes in heart ultrastructure, junctional complexes, mitochondria size and form, and so on. Early HFD feeding induced overweight, oxidative stress, and metabolic alterations in plasma and the heart of prepubertal rabbits, whereas lipotoxicity has especially a negative impact on male plasma but affects more the female heart ultrastructure.
Early obesity is increasing worldwide and represents a serious health issue with an elevated risk of cardiovascular disease [1, 2]. Numerous clinical and epidemiological studies point to a strong link between body weight and heart disease in several populations. High-fat diets have been correlated with excess body weight and a higher occurrence of hypertrophic cardiomyopathy . However, the influence of body weight on serum lipids is often overlooked in clinical practice. Excess body weight is indeed associated with higher plasma triglyceride, LDL cholesterol, fasting glucose levels, and lower HDL cholesterol content [4, 5]. Moor de Burgos et al.  noted a significant decrease in serum antioxidant vitamin levels (ascorbic acid) and a higher prevalence of vitamin deficiency and dyslipidemia in obese women. For Galili et al. , early phases of abdominal overweight/obesity are characterized by coronary endothelial dysfunction, vascular oxidative stress, and light lipid profile abnormalities.
The aim of this study is to analyze the gender-specific effect of early high-fat diet feeding on cardiac biochemistry and ultrastructure of prepubertal rabbit, an animal model which mimics the main changes that occur in humans.
In summary, this experimental investigation demonstrates that high-fat feeding induces plasma lipid disorders and CK-MB increase in the two prepubertal genders. Male plasma parameters are more affected by this HFD than those of females. On the other hand, body weight, heart/body weight ratio, heart TG, and UA levels are significantly increased in FHFD when the protective parameters decrease (AA, AOA). The Ca++ transport disturbance (contraction/relaxation process alteration) result in cardiac pathophenotypes and structural abnormalities (mitochondrial enlargement, duplication, and cristae loss). This is an interesting issue in view of the association between overweight, dyslipidemia, oxidative stress, and heart diseases in prepubertal models. The lipotoxicity we obtained by this HFD via ROS overproduction and mitochondrial damage may result in activation of apoptotic cascades and play roles in the pathogenesis of cardiomyopathy in both female and male, even so at the prepubertal stage.