Nutritional hepatic steatosis and mortality after burn injury in rats

Abstract

To investigate the effects of diet composition and starvation on hepatic steatosis and mortality after severe burn injury in rats. Experiment 1: rats received either normal chow (55 cent of energy carbohydrates, 14 cent fat, 31 cent protein), a high-fat (40 cent carbohydrates, 40 cent fat, 20 cent protein), or a high-carbohydrate diet (81 cent carbohydrates, 4 cent fat, 15 cent protein) ad libitum for 6 days. Another three groups received these diets ad libitum for 6 days after 48|h starvation. Experiment 2: mortality after 60 cent total body surface area scald burn was determined in a control group of rats and a group with nutritionally induced hepatic steatosis. Hepatic steatosis was induced by feeding the rats a high-fat diet (40 cent carbohydrates, 4 cent fat, 15 cent protein) ad libitum for 6 days. Without starvation, liver triglyceride content (mg/g liver) increased in response to the high-fat diet (25.6'6.9) compared to normal chow (9.4'3.8; P < 0. 05); the high-carbohydrate diet had no influence on liver triglyceride content (12.4'3.7). Refeeding after starvation resulted in elevated (P < 0.05) liver triglyceride content in the high-fat (18.8'8.3) and the high-carbohydrate group (28.7'14.4 vs control 6. 7'3.7). Liver triglyceride content correlated (R2=0.72; P < 0.05) to non-protein energy intake but not to total energy intake. Burn caused 33 cent mortality in the hepatic steatosis group and no deaths in the control group (P < 0.05). Diet composition and preceding starvation independently manipulate hepatic fat content in rats. Hepatic steatosis increases mortality after burn injury. Thus, nutritional interventions to reduce hepatic fat accumulation may be beneficial.