Lipids form a diverse group of water-insoluble molecules that include triacylglycerides, phosphoglycerides, sterols and sphingolipids. They play several important roles at cellular and organismal levels. Fatty acids are the major building blocks for the synthesis of triacylglycerides, which are mainly used for energy storage. Phosphoglycerides, together with sterols and sphingolipids, represent the major structural components of biological membranes. Lipids can also have important roles in signalling, functioning as second messengers and as hormones. There is increasing evidence that cancer cells show specific alterations in different aspects of lipid metabolism. These alterations can affect the availability of structural lipids for the synthesis of membranes, the synthesis and degradation of lipids that contribute to energy homeostasis and the abundance of lipids with signalling functions. Changes in lipid metabolism can affect numerous cellular processes, including cell growth, proliferation, differentiation and motility. This review will examine some of the alterations in lipid metabolism that have been reported in cancer, at both cellular and organismal levels, and discuss how they contribute to different aspects of tumourigenesis.

https://febs.onlinelibrary.wiley.com/doi/epdf/10.1111/j.1742-4658.2012.08644.x

Lipid metabolism in cancer

https://www.gastrojournal.org/article/S0016-5085(82)80339-9/pdf

Utilization of nutrients by isolated epithelial cells of the rat colon.

A variety of neurotransmitters, hormones, and other regulatory agents affect the phosphorylation of specific proteins in their target tissues. The types of stimuli that share this common effect on protein phosphorylation include numerous substances that do not act through cyclic AMP. These and other observations suggest that many different classes of regulatory substances achieve certain of their biological effects by altering the phosphorylation of specific proteins.

http://science.sciencemag.org/content/sci/199/4325/146.full.pdf

Phosphorylated proteins as physiological effectors

The colonic epithelium in ulcerative colitis: an energy-deficiency disease?

FoxO1 regulates multiple metabolic pathways in the liver: effects on gluconeogenic, glycolytic, and lipogenic gene expression

Plasma insulin concentrations in fed rats were altered acutely by administration of glucose or anti-insulin serum. Rates of fatty acid synthesis in adipose tissue and liver were estimated from the incorporation of 3H from 3H2O. In the adipose tissue dehydrogenase and acetyl-CoA carboxylase were evident. In liver, although changes in rates of fatty acid synthesis were found, the initial activity of pyruvate dehydrogenase did not alter, but small parallel changes in acetyl-CoA carboxylase activity were observed.

/pdf/acute-effects-in-vivo-of-anti-insulin-serum-on-rates-of-1n17bhioy6.pdf

Acute effects in vivo of anti-insulin serum on rates of fatty acid synthesis and activities of acetyl-coenzyme A carboxylase and pyruvate dehydrogenase in liver and epididymal adipose tissue of fed rats.

Dichloroacetate and other halogenated carboxylic acids can activate pyruvate dehydrogenase in rat heart and in rat heart mitochondria by effecting conversion of phosphorylated (inactive) pyruvate dehydrogenase into an active (dephosphorylated) form. These compounds are inhibitors of pig heart pyruvate dehydrogenase kinase. Pig heart pyruvate dehydrogenase phosphate phosphatase requires both Mg2+and Ca2+ for activity. Evidence is given for a dual metal requirement of the phosphatase in rat fat cell mitochondria. It is concluded that Mg2+ and Ca2+ are essential cofactors for the phosphatase but that their physiological significance as regulators remains to be established. Pig heart pyruvate dehydrogenase kinase is inhibited by high concentrations of magnesium and by low concentrations of calcium.

Regulation of mammalian pyruvate dehydrogenase.

1. Pyruvate dehydrogenase phosphate phosphatase activity in rat epididymal fat-pads was measured by using pig heart pyruvate dehydrogenase [32P]phosphate. About 80% was found to be extramitochondrial and therefore probably not directly concerned with the regulation of pyruvate dehydrogenase activity. The extramitochondrial activity was sensitive to activation by Ca2+, but perhaps less sensitive than the mitochondrial activity.

Regulation of pyruvate dehydrogenase and pyruvate dehydrogenase phosphate phosphatase activity in rat epididymal fat-pads. Effects of starvation, alloxan-diabetes and high-fat diet.

David Stansbie

Papers

Acute effects in vivo of anti-insulin serum on rates of fatty acid synthesis and activities of acetyl-coenzyme A carboxylase and pyruvate dehydrogenase in liver and epididymal adipose tissue of fed rats.

Regulation of mammalian pyruvate dehydrogenase.

Regulation of pyruvate dehydrogenase and pyruvate dehydrogenase phosphate phosphatase activity in rat epididymal fat-pads. Effects of starvation, alloxan-diabetes and high-fat diet.

Regulation of the Conversion of Glucose into Fat in White Adipose Tissue by Insulin

Inhibition of the activity of the 2-oxoacid dehydrogenase complexes by sera from patients with primary biliary cirrhosis