Food deprivation and refeeding influence growth, nutrient retention and functional recovery of rats

The objective of this work was to determine the effects of starvation and refeeding on growth, nutritional recovery and intestinal repair in starved rats. Male Wistar rats, weighing 200 g, were starved for 3 d, then refed a soy-based diet for another 3 d. Normally fed rats were given the same diet and used as controls. The variables assessed were as follows: body weight gain and nitrogen retention during recovery after starvation; muscle glutamine concentration; tissue protein content; gut mucosa and liver glutathione levels; intestinal permeability to ovalbumin, lactulose and mannitol; and intestinal tissue apoptosis. Starvation was associated with lower muscle glutamine levels and intestinal mucosa impairment, including a lower content of mucosal protein, a higher level of oxidized glutathione, enhanced permeability to macromolecules and greater numbers of apoptotic cells. Refeeding for 3 d resulted in rapid repair of gut atrophy and normalization of not only intestinal permeability but also of the majority of metabolic markers assessed in other tissues. In conclusion, with the use of severely starved rats, we have established a reversible experimental animal model of malnutrition that might prove useful in comparing the effectiveness of different enteral diets.