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Abstract: Over the two last decades, isolation and characterization of proteins involved in transport and metabolic fate of long-chain fatty acids have provided new insights on the molecular basis of fat absorption. This systematic cloning period has been followed by the functional genomics time which led to surprises. Indeed, disruption of several genes, thought to be crucial for long-chain fatty acid absorption, did not lead to clear phenotypes. This observation raises the question about the real physiological role of several lipid-binding proteins and enzymes found in the enterocyte. This mini-review assesses the present knowledge concerning the main steps of intestinal fat absorption: the cellular uptake and trafficking of long-chain fatty acids and the lipoprotein synthesis. [Copyright &y& Elsevier]

Abstract: Aim. – This study aimed at defining how many fats require sportsmen with a high volume of training. Materials and method. – Nineteen ultra athletes and cyclists volunteered to take part. We assessed lipid intake with a 4-day dietary recall and a frequency questionnaire, in order to have a more precise quantification as possible. Results. – Our results showed first that in spite of a mean fat intake of 1.5 g/kg per day, eighteen out of our nineteen subjects presented with a biological abnormality, most of which concerned “omega 3” fats. Dietary recall did not help predicting any deficiency, except for “omega 3”. Every time rapeseed oil was not consumed, biological abnormalities were seen. Moreover, a carbohydrate intake below 6 g/kg per day increased the probability for a subject to have his biological fatty acids status being disturbed. Conclusion. – We concluded that “safety fat intakes” must be increased to 1.3 g/kg per day and that a high quality is required for fats. When rapeseed oil is lacking, “omega 3” requirements are harder to meet, even with fats intake far beyond 1,5 g/kg per day. Moreover, an optimal carbohydrate intake is necessary in order to meet fats requirements. [Copyright &y& Elsevier]

Circulating phospholipids carrying a single esterified fatty acid, the so-called lysophospholipids, are now considered as mediators of the intercellular communication. Their major members are the lysophosphatidic acid and the sphingosine 1-phosphate, two molecules displaying biological activities similar to those of growth factors or cytokines, through a recently identified subfamily of G protein-coupled receptors. They are involved in various biological processes, e.g., brain development and angiogenesis, but the following evidences suggest that these lipids are also significant actors of tumour development: (i) they stimulate the growth, survival and migration of tumour cells from various origins (ovary, prostate, glioblastoma…); (ii) they are abundant in malignant effusions; (iii) the lysophospholipid-producing enzymes are tumourigenic. Even if it remains necessary to define the role of these “oncolipids” in relationship with oncogenes and tumor suppressors, they may well be the mediators of an efficient autostimulatory system of the proliferating and migratory capacities of cancer cells, suggesting that lysophospholipids could represent novel valuable targets for anticancer pharmacology. [Copyright &y& Elsevier]