The over consumption of omega-6 polyunsaturated-fats in the westernized population has increased dramatically over the past 150 years. This dietary-shift is one of the largest dietary changes that has happened since the dawn of agriculture. Levels of arachidonic-acid and linoleic-acid in humans is at the highest-point it has ever been. Fat-cells (white adipose tissue or WAT) are able to convert into what is known as brown-adipose-tissue (BAT). BAT is a type of fat that generates lots of energy and gives off heat. Accumulation of this type of fatty tissue as opposed to WAT, decreases your chance of diabetes and heart-disease. The accumulation of arachidonic-fat (AA) in fat-cells produces prostaglandins that inhibit the conversion of WAT into BAT. BAT also doesn't contain any aromatase enzymes to my knowledge, unlike WAT. Here is the abstract:
Mol Metab. 2014 Dec; 3(9): 834–847.
The ω6-fatty acid, arachidonic acid, regulates the conversion of white to brite adipocyte through a prostaglandin/calcium mediated pathway
Didier F. Pisani, Rayane A. Ghandour,Guillaume E. Beranger,
Abstract
Objective
Brite adipocytes are inducible energy-dissipating cells expressing UCP1 which appear within white adipose tissue of healthy adult individuals. Recruitment of these cells represents a potential strategy to fight obesity and associated diseases.
Methods/Results
Using human Multipotent Adipose-Derived Stem cells, able to convert into brite adipocytes, we show that arachidonic acid strongly inhibits brite adipocyte formation via a cyclooxygenase pathway leading to secretion of PGE2 and PGF2α. Both prostaglandins induce an oscillatory Ca++ signaling coupled to ERK pathway and trigger a decrease in UCP1 expression and in oxygen consumption without altering mitochondriogenesis. In mice fed a standard diet supplemented with ω6 arachidonic acid, PGF2α and PGE2 amounts are increased in subcutaneous white adipose tissue and associated with a decrease in the recruitment of brite adipocytes.
Conclusion
Our results suggest that dietary excess of ω6 polyunsaturated fatty acids present in Western diets, may also favor obesity by preventing the “browning” process to take place.
Edited by misterE, 14 April 2016 - 04:28 AM.
