Fish Oil Decreases Hepatic Lipogenic Genes in Rats Fasted and Refed on a High Fructose Diet

Author(s)

de Castro, Gabriela S. ^{[1, 2]} ; Cardoso, Joao Felipe R. ^[3] ; Calder, Philip C. ^[2] ; Jordao, Alceu A. ^[1] ; Vannucchi, Helio ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Internal Med, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Univ Southampton, Human Dev & Hlth Acad Unit, Fac Med, Southampton SO16 6YD, Hants - England

^[3] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Pathol, BR-14049900 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: NUTRIENTS; v. 7, n. 3, p. 1644-1656, MAR 2015.
• Web of Science Citations: 9

Abstract

Fasting and then refeeding on a high-carbohydrate diet increases serum and hepatic triacylglycerol (TAG) concentrations compared to standard diets. Fructose is a lipogenic monosaccharide which stimulates de novo fatty acid synthesis. Omega-3 (n-3) fatty acids stimulate hepatic beta-oxidation, partitioning fatty acids away from TAG synthesis. This study investigated whether dietary n-3 fatty acids from fish oil (FO) improve the hepatic lipid metabolic response seen in rats fasted and then refed on a high-fructose diet. During the post-prandial (fed) period, rats fed a FO rich diet showed an increase in hepatic peroxisome proliferator-activated receptor alpha (PPAR-alpha) gene expression and decreased expression of carbohydrate responsive element binding protein (ChREBP), fatty acid synthase (FAS) and microsomal triglyceride transfer protein (MTTP). Feeding a FO rich diet for 7 days prior to 48 h of fasting resulted in lower hepatic TAG, lower PPAR-alpha expression and maintenance of hepatic n-3 fatty acid content. Refeeding on a high fructose diet promoted an increase in hepatic and serum TAG and in hepatic PPAR-alpha, ChREBP and MTTP expression. FO did not prevent the increase in serum and hepatic TAG after fructose refeeding, but did decrease hepatic expression of lipogenic genes and increased the n-3 fatty acid content of the liver. n-3 Fatty acids can modify some components of the hepatic lipid metabolic response to later feeding with a high fructose diet. (AU)

• FAPESP's process: 10/00408-1 - Effects of Fish Oil N-3 Fatty Acids on Lipid Metabolism and Gene Expression in Rats Fed a High-Fructose Diet
• Grantee: Gabriela Salim Ferreira de Castro
• Support Opportunities: Scholarships in Brazil - Doctorate