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Undernutrition still affects mothers and children in developing countries and thus remains the major focus of nutritional intervention efforts. Neuronal development, which classically includes neurogenesis, migration, maturation, and synapse refinement, begins in utero and continues into the early postnatal period. These processes are not only genetically regulated but also clearly susceptible to environmental manipulation. Dietary deprivation during early life is known to have adverse effects on brain anatomy, physiology, and biochemistry, and may even lead to permanent brain damage. Although all nutrients are important for the structural development of the central nervous system, lipids such as long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (22:6 n-3) and arachidonic acid (20:4 n-6), are important for normal brain development. The purpose of this literature review is to examine how early undernutrition involving a deficiency in long-chain polyunsaturated fatty acids can affect brain development and function and produce deficits in spatial cognitive learning ability.

The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15-19 years, 1-90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n-3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t-18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t-18:1), whereas rumenic acid (9c,11t-18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n-3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants.

A identificação da leptina, hormônio secretado pelos adipócitos, cujo efeito sobre o sistema nervoso simpático e a função endócrina confere participação ativa no controle do dispêndio energético, bem como do apetite, acrescentou às funções do tecido adiposo no organismo humano o papel de órgão multifuncional, produtor e secretor de inúmeros peptídeos e proteínas bioativas, denominadas adipocitocinas. Alterações na quantidade de tecido adiposo, como ocorrem na obesidade, afetam a produção da maioria desses fatores secretados pelos adipócitos. Ainda que essas alterações estejam freqüentemente associadas às inúmeras disfunções metabólicas e ao aumento do risco de doenças cardiovasculares, permanece sob investigação o envolvimento do tecido adiposo no desenvolvimento dessas complicações, considerada a sua função endócrina. As concentrações de várias adipocitocinas elevam-se na obesidade e têm sido relacionadas à hipertensão (angiotensinogênio), ao prejuízo da fibrinólise (inibidor do ativador de plasminogênio-1) e à resistência à insulina (proteína estimuladora de acilação, fator de necrose tumoral-α, interleucina-6 e resistina). De outro modo, leptina e adiponectina têm efeitos sobre a sensibilidade à insulina. Na obesidade, a resistência insulínica também está relacionada à resistência à leptina e aos teores plasmáticos reduzidos de adiponectina. Leptina e adiponectina ainda exercem efeitos orgânicos adicionais distintos: frente à participação da leptina no controle da ingestão alimentar, a adiponectina apresenta potente ação anti-aterogênica. Algumas drogas utilizadas no controle do diabetes elevam a produção endógena de adiponectina, em roedores e humanos, indicando que o desenvolvimento de novos medicamentos com alvo nas adipocitocinas pode representar uma alternativa terapêutica de prevenção da resistência insulínica e da aterosclerose em indivíduos obesos.Termos de indexação: adipocitocinas; aterosclerose; obesidade; resistência à insulina; tecido adiposo. A B S T R A C TLeptin is a hormone secreted by adipocytes whose effect on the sympathetic nervous system and endocrine function confers active participation in the control of energy expenditure and appetite. Its identification added to the fat tissues in the human body the role of a multifunctional organ that produces and secretes a