Efeito da suplementação materna com óleo de chia sobre parâmetros metabólicos e de estresse oxidativo hepático em modelo animal de hiperalimentação neonatal

Abstract

Maternal nutrition and fatty acid consumption during gestational and/or lactation periods are critical determinants strongly related to normal fetal and postnatal development. On the other hand, changes in offspring nutrition in the early stages of life may predispose to the development of metabolic disorders. In this sense, compounds that act in the prevention and/or reversal of these disorders have been sought. Chia oil (OC) stands out as a promising food due to its high content of α-linolenic acid (55-66%) and phenolic compounds. Therefore, the objective of the present study was to evaluate the effect of maternal OC supplementation on metabolic parameters and hepatic oxidative stress in a neonatal hyperalimentation model.The oils used during the experiment were extracted and characterized. Maternal supplementation with OC (5g/kg bw) or corn oil (OM), as a negative control at the same dose, occurred during mating until weaning (21 days) of the pups. The formation of the hyperfed groups occurred by reducing the litter size to 3-4 puppies with each female during breastfeeding. Thus, considering maternal supplementation and the model, the animals were divided into six experimental groups: Control (C), Postnatal hypernutrition (H), C supplemented with OC (COC), C supplemented with OM (COM), H supplemented OC (HOC) and H supplemented with OM (HOM). During the experimental period, the pups' weight gain was monitored weekly; in addition, at 120 days of life the animals were subjected to the oral glucose tolerance test (OGTT) and the insulin tolerance test (TSI). After euthanasia (at 120 days), samples were collected to evaluate blood glucose, lipid profile, insulinemia, lipid, oxidative stress and liver tissue parameters. The significance level adopted for the results was p<0.05. At 21 days the total body weight of group H was 26% greater than group C and 29% greater in group HOC compared to COC. At 120 days, only the HOC group showed a difference in relation to the COC, being 14% higher. The percentage of weight gain was 46% lower in the HOM group compared to the COM group. As for Lee's index, HOC was 10% higher than COC. The weight of the tissues did not show any significant difference. In the TTOG, the HOM group had a higher mean blood glucose level at times 0 and 120min compared to the COM group. In the TSI, the HOC group had lower blood glucose levels than the COC group at 15 minutes. Glycemia, insulinemia and lipid profile showed no statistical difference, except triglycerides in the COC group were higher compared to the COM group. Total lipids in the liver also showed no difference. Regarding oxidative stress, no statistical relevance was found. In histological analyses, all groups showed common characteristics for the tissue in question. The hyperalimentation model, despite being established in the literature as a model of excess weight and adipose tissue, with metabolic changes, was not completely established in the present work. Due to this fact, but not limiting it, no positive effects were verified by maternal supplementation with OC on the parameters generated by the proposed experimental model. More studies are still needed to improve the proposed metabolic programming model and more research is needed to elucidate the potential benefit of maternal supplementation with chia oil.