26 The Chemistry of the Injured Cell 



the latent energy of the molecule. This is done through the produc- 

 tion of acetyl-Co A units by the process of fi oxidation. The 2-carbon 

 fragments are incorporated into the tricarboxylic acid cycle along 

 with similar fragments derived from carbohydrate through pyru- 

 vate and oxidised by a series of catalysed reactions to C0 2 and 

 water. Oxidation of fatty acids is exclusively a mitochondrial func- 

 tion. At least part of the oxidation of choline takes place, too, in the 

 mitochondrion. In this way, through a series of remarkable synthe- 

 ses and reductions, fats are partly converted into phospholipids, 

 partly utilised for energy production with the liberation of water 

 and carbon dioxide. 



But there is an alternative reaction at the diglyceride stage. 

 Under certain circumstances we have seen that the cell may be 

 starved of choline; usually this happens because the supply from 

 food or stores in the body is understocked but sometimes it is the 

 outcome of a relative choline deficiency. Our colleagues, Dawkins, 

 Judah and Rees (see below) have shown that this may occur with 

 carbon tetrachloride intoxication. When there is not sufficient 

 choline phosphate for the production of cytidine-diphospho-cho- 

 line, diglyceride unites with another fraction of fatty acid— Co A 

 and neutral fat or triglyceride is produced. When this happens the 

 cell seems to store the neutral fat as granules or globules which are 

 not made use of for ordinary cellular metabolic activities, and this 

 constitutes the familiar fatty degeneration. This side-tracking of 

 metabolism is the result of a deficiency state or the outcome of a 

 pathological change in the cell. Such is the general theory behind 

 fatty degeneration, not only of liver cells but quite likely of all cells, 

 and, as we shall see later on, of demyelination of nerve fibres. 



GAUCHER'S DISEASE 



There is a group of disorders of familial nature in which there 

 is abnormal metabolism and accumulation of cerebrosides. 

 Gaucher's disease is the most important example and is character- 

 ised by the accumulation of kerasin in the reticulo endothelial 

 system in spleen, lymph nodes, liver, bone marrow and elsewhere. 

 Kerasin is a cerebroside, a normal constituent of nerve tissue and 

 consists of lignoceryl sphingosine combined with galactose. In addi- 



