Dietary lipid-induced changes in enzymes of hepatic lipid metabolism.

HURTADO DE CATALFO, GRACIELA E.; ALANIZ, MARÍA J.T. DE; MARRA, CARLOS ALBERTO

NUTRITION

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2012

0899-9007

Objective: To investigate the effect of different dietary oils on the main hepatic enzymes involved in  metabolism and their impact on the oxidative stress status. Methods: Twenty four male Wistar rats were fed for 60 d on the same basal diet plus different lipid sources as commercial oils: soybean-S, olive-O, coconut-C and grape-seed-G. After sacrifice, liver lipid fatty acid composition, enzymatic and non-enzymatic components of the antioxidant defense system and the activity of enzymes involved in lipid metabolism were determined. The concentration of [Ca++] in plasma and liver homogenates was also measured. Results: The diets produced significant changes in total and polar lipid fatty acid composition together with alterations on the key enzyme activities involved in lipid metabolism. S- and G-groups increased significantly the oxidative stress biomarkers. Enzymatic and non enzymatic components of the antioxidant defense system were elevated in O- and C-groups. The highest levels of nitrite plus nitrate [NOx] were observed in S- and G-groups compared with O and C in plasma and in liver homogenates. They were directly correlated with [Ca++] concentration. The most beneficial effects were obtained with olive oil. However, it was necessary to study in more detail appropriate mixtures of olive and soybean oils to provide adequate balance between n-3 and n-6 fatty acids. Conclusion: Different dietary oils modify lipid composition of plasma and liver, local and systemic antioxidant status, and the activity of key enzymes of lipid metabolism. The interrelationship between [Ca++] and [NOx]  could be the causal factor underlying the observed changes.