Dietary supplementation with hybrid palm oil alters liver function in the common Marmoset.

Hybrid palm oil, which contains higher levels of oleic acid and lower saturated fatty acids in comparison with African palm oil, has been proposed to be somehow equivalent to extra virgin olive oil. However, the biological effects of its consumption are poorly described. Here we have explored the effects of its overconsumption on lipid metabolism in a non-human primate model, the common marmoset. Dietary supplementation of marmoset with hyperlipidic diet containing hybrid palm oil for 3 months did not modify plasma lipids levels, but increased glucose levels as compared to the supplementation with African palm oil. Liver volume was unexpectedly found to be more increased in marmosets consuming hybrid palm oil than in those consuming African palm oil. Hepatic total lipid content and circulating transaminases were dramatically increased in animals consuming hybrid palm oil, as well as an increased degree of fibrosis. Analysis of liver miRNAs showed a selective modulation of certain miRNAs by hybrid palm oil, some of which were predicted to target genes involved in cell adhesion molecules and peroxisomal pathways. Our data suggest that consumption of hybrid palm oil should be monitored carefully, as its overconsumption compared to that of African palm oil could involve important alterations to hepatic metabolism.

trans Fatty Acids in Colostrum, Mature Milk and Diet of Lactating Adolescents.

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.

Effect of variation of trans-fatty acid in lactating rats' diet on lipoprotein lipase activity in mammary gland, liver, and adipose tissue.

OBJECTIVE: Lactation is associated with an increase in lipoprotein lipase (LPL) activity in the mammary gland (MG) and a decrease in adipose tissue because lactation redirects circulating substrates to the MG for milk synthesis. We investigated the effects of different dietary contents of trans-fatty acid (TFA) on LPL activity in maternal tissues and fatty acid composition in milk. METHODS: Lactating rats were fed semisynthetic isocaloric diets containing 7% soy oil (control), 7% partially hydrogenated vegetable oil (7%-PHVO), 5% PHVO plus 2% soy oil (5%-PHVO), or 3.5% PHVO plus 3.5% soy oil (3.5%-PHVO). On lactation day 14, animals were decapitated and MG, liver, and parametrial adipose tissue were extracted to determine total lipid contents, percentages of TFA, and LPL activity. Milk lipid composition was examined by gas chromatographic analysis of the gastric content of 14-d-old suckling pups. RESULTS: Maternal consumption of TFA increased dietary TFA incorporation in MG and liver and decreased it in parametrial adipose tissue. Diets with higher trans concentrations (7%-PHVO) significantly increased lipid content in the MG, and all groups fed trans-based diets showed significant increases in LPL activity in the MG. Although LPL increased in the MG, milk of rats fed TFA-based diets had significant decreases in the percentage of essential fatty acids. CONCLUSIONS: TFA intake during lactation alters maternal lipid metabolism and the percentage of essential fatty acids in milk; therefore, it is important to alert the population to avoid excessive intake of TFAs during lactation.