Proanthocyanidins modulate triglyceride secretion by repressing the expression of long chain acyl-CoA synthetases in Caco2 intestinal cells

In this work we determined the ability of grape seed proanthocyanidins (GSPE) to modulate triglyceride (TG) secretion by enterocytes in post-prandial and fasting states, using Caco2 cell line. GSPE did not modify TG secretion in the post-prandial state, even though it modulated the long chain acyl-CoA synthetase (ACSL) 5 and the carnitine-palmitoyl-transferase-1a gene expression. On the contrary, GSPE decreased TG secretion in the fasting state, significantly repressing ACSL3, ACSL5, I-FABP and PPARalpha gene expression. Intestinal cells can use two different pathways to carry out TG synthesis. Fatty acids (FA) delivered by ACSL3 and by ACSL5 would be directed towards the monoacylglycerol and glycerol-3-phosphate pathways, respectively. Therefore, proanthocyanidins repress the supply of FA towards the monoacylglycerol pathway in the post-prandial state, whereas they repress the supply of FAs towards both pathways in the fasting state, suggesting that the feeding state is a key factor regarding the effectiveness of proanthocyanidins to reduce triglyceridaemia.