NUTRITIONAL FACTORS REQUIRED FOR ALCOHOLIC LIVER-DISEASE IN RATS

Decades ago it was suggested that nutritional factors are important in the development of alcoholic liver disease (ALD). However, several mo dels of experimental alcoholism considered that the diets fed to anima ls were nutritionally adequate, complete and balanced. Therefore, a co ncept prevailed that the effects observed were due to alcohol per se a nd that they occurred despite a nutritionally adequate status in the a nimal. Examination of various models revealed that animals were malnou rished because they ingested reduced levels of macro- and micronutrien ts. Furthermore, they consumed only small amounts of carbohydrate and a high level of unsaturated fat for long periods during the developmen t of ALD. Alcoholic rats show many effects of inadequate nutritional s tatus, such as a slow growth, depressed levels of liver glycogen and p ancreatic amylase, enhanced protein degradation and circulating levels of branched-chain amino acids, and increased levels of enzymes involv ed in gluconeogenesis and alterations in the activities of enzymes rel ated to the metabolism of carbohydrate as compared with controls. Chro nic consumption of alcohol did not result in fatty liver, high blood a lcohol concentration (BAG) or other observed effects when intake of en ergy, carbohydrate and other nutrients was increased. Furthermore, pre -existing effects of alcohol consumption, such as fatty liver, BAC and delayed gastric emptying, were reversed in rats receiving increased e nergy and carbohydrate intakes while continuing alcohol ingestion. Thu s, nutritional status of the animal determines the production or preve ntion of ALD or other effects that were considered to be due to alcoho l alone.