Nutritional hepatic steatosis and mortality after burn injury in rats

Aims: To investigate the effects of diet composition and starvation on hepa tic steatosis and mortality after severe burn injury in rats. Methods: Experiment 1: rats received either normal chow (55% of energy carb ohydrates, 14% fat, 31% protein), a high-fat (40% carbohydrates, 40% fat, 2 0% protein), or a high-carbohydrate diet (81% carbohydrates, 4% fat, 15% pr otein) 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% total body surface area scald burn was determined in a control group of ra ts and a group with nutritionally induced hepatic steatosis. Hepatic steato sis was induced by feeding the rats a high-fat diet (40% carbohydrates, 4% fat, 15% protein) ad libitum for 6 days. Results: Without starvation, liver triglyceride content (mg/g liver) increa sed 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 e levated (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 t riglyceride content correlated (R-2=0.72; P < 0.05) to non-protein energy i ntake but not to total energy intake. Burn caused 33% mortality in the hepa tic steatosis group and no deaths in the control group (P < 0.05). Conclusions: Diet composition and preceeding starvation independently manip ulate hepatic fat content in rats. Hepatic steatosis increases mortality af ter burn injury. Thus, nutritional interventions to reduce hepatic fat accu mulation may be beneficial.