Coconut oil induces short-term changes in lipid composition and enzyme activity of chick hepatic mitochondria.

We studied the short-term effects of a 20% coconut oil supplementation to the chick diet on lipid composition of liver and hepatic mitochondria, and changes that occurred in mitochondrial-associated enzymes as a result of this diet. No significant differences were observed in the lipid contents of liver when young chicks were fed the experimental diet, whereas hepatic mitochondria rapidly changed in response to this diet. Total cholesterol significantly increased in mitochondria at 24 hours of coconut oil diet feeding and decreased when dietary treatment was prolonged for 5 to 14 days.

Differential effects of dietary fat on chick plasma and liver composition and HMG-CoA reductase activity.

The comparative effects of diet supplementation with 10% saturated fat rich in 12:0 and 14:0 fatty acids (coconut oil), without and with 1% added cholesterol, and with 10% unsaturated fat rich in n-3 polyunsaturated fatty acids (menhaden oil) on cholesterol metabolism in neonatal chicks were examined to clarify the different mechanisms of their hyper- and hypolipidemic action. Supplementation of coconut oil produced a significant hypercholesterolemia after 7 days of treatment, with a similar increase in the amount of both free and esterified cholesterol. Supplementation of coconut oil plus cholesterol produced a higher increase of plasma cholesterol levels (approximately two to three times higher than those found with standard diet).

Influence of fasting status on the effects of coconut oil on chick plasma and lipoprotein composition.

For a better understanding of the hyperlipidemic function of saturated fat, we have studied the effects of diet supplementation with 10-20% coconut oil on the chick plasma and lipoprotein composition under postprandial and starvation conditions. A significant hypercholesterolemia was found in chicks fed the standard diet after 12 h of food deprivation. In these conditions, LDL-cholesterol also increased, whereas triglyceride levels were reduced in HDL, VLDL and chylomicron fractions.

Influence of dipyridamole on the fatty acid composition of the main lipid classes of chick serum.

We have studied the effects of dipyridamole treatment on the fatty acid composition of the main lipid classes of chick serum bearing in mind the relationship between platelet aggregation and eicosanoids production from arachidonic acid. In the free fatty acids, percentages of MUFA and n-6 PUFA fell. The effects of dipyridamole appeared to be less pronounced in triglyceride fraction, but more so in serum phospholipids and cholesterol esters.

Differential changes in the fatty acid composition of the main lipid classes of chick plasma induced by dietary coconut oil.

For a better understanding of the hyperlipidemic function of saturated fat, we have studied the comparative effects of diet supplementation with 10 and 20% coconut oil on the main lipid classes of chick plasma. Changes in fatty acid composition of free fatty acid and triglyceride fractions were parallel to that of the experimental diet. Thus, the increase in the percentages of 12:0 and 14:0 acids may contribute to the hypercholesterolemic effects of coconut oil feeding.