Fermented Milks from Small Ruminant: Effect on Metabolism and Immune Status of Mice Fed Mild Caloric Restricted Diet

Abstract

The purpose of this study was to evaluate the effect of the administration of Fermented Goat´S Milks (FGMs) in mice fed mild caloric restricted diet. The ability of these FGMs to ameliorate immune and metabolic parameters related to mild caloric restriction was studied. We also analyzed if the time (45 or 90 days) of caloric restriction have influence on leptin secretion, IgA+ cells number and phagocytic activity of peritoneal macrophages, and also test the correlation between these parameters. Mice were fed with a mild caloric restricted diet during 45 or 90 days. After these periods of caloric restriction, mice were refed with balanced conventional diet (BCD) plus goat´s milks or BCD plus goat´s milks fermented with Lactobacillus rhamnosus CRL1425 (FGM-Lr) or Lactobacillus casei CRL431 (FGM-Lc). All renutrition diets induced an increase of serum glucose, triglycerides, total proteins and leucocytes cells. A decrease in cholesterol levels was observed after the diets. FGM-Lr induced lower triglycerides values than others diets. All FGMs restore IgA+ cells in intestinal mucosa, and the FGM-Lc group had higher positive cells number than the ad libitum control. Furthermore, phagocytic activity of peritoneal macrophages only increased in mice fed with FGM-Lc. Mild caloric restriction induced a decrease on leptin circulating values at 90 days. The renutrition with FGM-Lr lead to lower leptin levels than mild caloric restriction controls, while FGM-Lc induced higher leptin levels. Positive correlation between serum leptin concentration and immune parameters was observed in all groups under study. We showed that leptin levels could positively predict the immune mucosal competence in mild caloric restricted mice. These results suggest that the FGMs are able to modulate, in different way, serum leptin levels, IgA+ cells number and phagocytic activity. Furthermore, FGM-Lc could be more effective for nutritional treatment in malnutrition status.