Trans fatty acids in maternal milk lead to cardiac insulin resistance in adult offspring

Objective Trans fatty acids (TFAs) are derived from vegetable oil hydrogenation and can be found in most manufactured food products. Our main objective was to evaluate the effects of TFA consumption by lactating dams on cardiac glucose metabolism of adult offspring by analyzing glucose transporter-4 in the left ventricle. To investigate the energy homeostasis, insulin sensitivity and hepatic glycogen content were also measured. Methods Lactating Wistar rats were divided into a control group or a TFA group. The control group received a diet containing soybean oil, and the TFA group received a diet containing partially hydrogenated vegetable oil (total trans concentration of about 10.58 mg/g, 11.75%, of total fat) throughout the lactation period. At weaning, pups from both groups received a standard chow until 60 d of age, at which time the quantity of glucose transporter-4 in the left ventricle and hepatic glycogen were measured. Moreover, insulin sensitivity was analyzed by assessing the insulin/glucose ratio and the homeostatic model assessment index. Results TFA consumption by the pups during lactation led to a significant decrease in the cardiac content of glucose transporter-4 (P < 0.05) and in the hepatic content of glycogen (P < 0.05). Moreover, we observed impaired insulin sensitivity in the TFA group (insulin/glucose ratio and homeostatic model assessment index, P < 0.05) in adulthood. Conclusion Our data suggest that the consumption of hydrogenated fat, rich in TFAs, by the mothers during the lactation period caused cardiac insulin resistance in the adult progeny, thus reinforcing the hypothesis that early adaptations may cause deleterious consequences later in life.