Observations on enzymes in the human liver: general considerations and preliminary results

ABSTRACT

It has long been supposed that malnutrition predisposes the liver to injury. An attempt has been made to characterize this vulnerable state in biochemical terms. A diet deficient in protein causes the liver cell to lose a large proportion of its cytoplasmic protein and ribonucleic acid. It is suggested that this might lead to a disturbance in the amount or pattern of enzymes, which could have serious metabolic consequences. To test this hypothesis, measurements were first made of a number of single-enzyme systems, e.g. dehydrogenases transaminase choline esterase, cytochrome oxidase, cytochromec reductase. Only choline esterase was reduced in activity in the malnourished liver; the other enzymes were well preserved. Preliminary evidence suggests that more complex systems,involving a chain of enzymes, may be more easily damaged. (AU)