Incorporação de ácidos graxos trans e seus efeitos em diferentes fases do crescimento de ratos

• Ano de defesa: 2007
• Autor(a) principal: Lessa, Nilma Maria Vargas
• Orientador(a): Costa, Neuza Maria Brunoro
• Banca de defesa: Matta, Sérgio Luis Pinto da , Silva, Marco Túlio Coelho
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Ciência da Nutrição
• Departamento: Valor nutricional de alimentos e de dietas; Nutrição nas enfermidades agudas e crônicas não transmis
• País: BR
• Palavras-chave em Português: Nutrição humana; Ácidos graxos trans
• Palavras-chave em Inglês: Human nutrition; Trans fatty acids
• Área do conhecimento CNPq: CNPQ::CIENCIAS DA SAUDE::NUTRICAO::BIOQUIMICA DA NUTRICAO
• Link de acesso: http://locus.ufv.br/handle/123456789/2801

Clinical, epidemiological and experimental evidences certify the role of trans fatty acids in the genesis of non-transmissible chronic diseases. The atherogenic effects of trans fatty acids produced by industrialization process are well known in adult subjects. However, little is known about its effects on maternal-infantile and infantile-juvenile populations. Therefore, the objective of this study was to evaluate the effects of trans fatty acid intake on blood lipid profile and its deposition in the liver, adipose tissue and serum of Wistar rats after birth, weaning and growth states. Hence, 40 female rats and their male offspring were used, 20 newborn, 20 weaning and 20 young adults were separated into control and trans groups in each phase. The animals during pregnancy and during growth of both groups received AIN-93 diet with modifications. The source of trans fatty acids was hydrogenated vegetable fat at 5% of the energy of the diet. After birth, weaning and growth, the rats were euthanized and the abdominal adipose tissue, liver and serum were collected. It was determined the lipid profile by gas chromatography after lipid extraction by direct methylation. It was analyzed the levels of serum total cholesterol, HDL-cholesterol, triacylglycerol and glucose as well as the liver morphometric analysis and hepatic- somatic index. The data were analyzed by t-test of Student and analysis of variance ANOVA, and the Pearson correlation to evaluate the relation between essential fatty acids. The results showed that trans fatty acid accumulated in higher proportion in the liver and adipose tissue of the newborn rats (P<0.05). However, the accumulation of trans fatty acids in the liver did not affect the synthesis of long chain fatty acids, probably due to the adequacy of the requirement of essential fatty acids. There was negative and significant correlations (P<0.001) between trans fatty acids and linoleic acid in the adipose tissue of weaning and young adult rats, and between linolenic and aracdonic acid in the adipose tissue of young adult rats. Fasting blood glucose was higher in young adult rats fed trans fatty acids than the control (P=0.004). The liver morphometric analysis showed higher lipid accumulation in rats fed trans fatty acids than the control group in all phases, and the difference was significant between newborn and weaning rats (P<0.01). The hepatic-somatic index showed significant difference between groups in the young adult rats (P<0.05). In conclusion, trans fatty acids accumulated in the adipose tissue, liver and serum at different ways in the analyzed phases, and promoted hyperglycemia in young adult rats and higher accumulation of lipids in the liver of newborn rats.