Maternal use of flaxseed oil during pregnancy and lactation prevents morphological alterations in pancreas of female offspring from rat dams with experimental diabetes

Diabetes mellitus (DM) is a group of metabolic disorders characterized by chronic hyperglycaemia caused by lack of insulin production by pancreatic beta-cells or by defects in insulin receptors on target cells, resulting in hyperglycaemic metabolic disease (American Diabetes Association 2014). DM is a chronic disease present throughout the world, currently affecting approximately 382 million people. The number of people with the disease is set to rise beyond 592 million in <25 years (International Diabetes Federation 2013). As the incidence of diabetes continues to increase and affect individuals of all ages, including young children, women of childbearing age are at increased risk to develop this disease during pregnancy (Hunt & Schuller 2007; Nolan et al. 2011). Pregnancy is a diabetogenic situation per se resulting from metabolic adaptations performed by the maternal metabolism to ensure adequate food support to the foetus (physiological insulin resistance). In predisposed women, this can lead to gestational diabetes. Women with gestational diabetes, as well as women with pregestational diabetes (type 1 or type 2), are classified as high-risk pregnancies, and their children show increased morbidity and mortality in the perinatal period (Plagemann 2011). Several studies have observed that insults occurring during intrauterine life are associated with several abnormalities, both functional and structural, at adulthood. Diabetes is a complication that, when it occurs during pregnancy, can substantially influence the development of offspring during foetal and postnatal life (Poston 2010; Plagemann 2011; Yessoufou & Moutairou 2011). Diabetes during pregnancy induces changes and adaptation in foetal pancreatic activity, in response to the increased supply of glucose from mother to foetus. Chronic hyperglycaemia in the intrauterine environment in pregnant rats induces hyperglycaemia and hypoinsulinaemia in the offspring at birth and is associated with foetal growth retardation. The foetal pancreas weight is decreased whereas the percentage of endocrine tissue is increased (Holemans et al. 2003; Fetita et al. 2006), and young adults exhibit mild glucose intolerance that worsened with time (Fetita et al. 2006). It is imperative to mention that the foetal programming of chronic diseases has important medical and economic ramifications. Recently it has been proposed that interventions during pregnancy and lactation may be effective in preventing disease in adulthood (Gluckman & Hanson 2004). With regard to therapy, researchers have suggested that n-3 polyunsaturated fatty acids (n-3 PUFAs) have the ability to prevent disease. Several benefits of n-3 PUFAs in relation to diabetes have been implicated, such as improvement in glucose homoeostasis, which involves several molecular mechanisms, such as stimulation of insulin signalling pathway (Wu et al. 2012). Polyunsaturated fatty acids of the n-3 family include eicosapentaenoic acid (EPA – 20:5n-3) and docosahexaenoic acid (DHA – 22:6n-3) from seafood and alpha-linolenic acid (ALA, 18:3n-3) from plant sources (Wu et al. 2012). Flaxseed has 57% of n-3, 16% of n-6, 18% of monounsaturated fatty acids and only 9% of saturated fatty acids (Morris 2007; de Almeida et al. 2009). Flaxseed is the seed of the flax plant (Linum usitatissimum L.) which is a member of the Linaceae family (de Almeida et al. 2009; Shim et al. 2014) and is widely used for its edible oil in many parts of the world (Naqshbandi et al. 2013). Due to the wide dissemination in the general media of the relationship between food and health, societal concern with functional food has increased exponentially. Functional foods are any food or ingredients that, beyond basic nutritional functions, when consumed as part of the usual diet, produce metabolic and/or physiological effects and/or health benefits, and should be safe for consumption without medical supervision (Guarda et al. 2014). Therefore, flaxseed, besides its by-products, such as its oil, can be framed as a functional food because it contains physiologically active components that may promote health benefits beyond basic nutrition. This study was designed to test whether maternal flaxseed oil use during pregnancy and lactation has an effect on glucose metabolism and pancreatic morphology of adult female offspring of diabetic Wistar rat.