Influence of Hyperferric and Hypoferric Diets on Iron Transporters Proteins in the Rat Mammary Glands.

Objectives: This study aimed to assess the expression of transferrin, lactoferrin and ferroportin at mammary glands of rats after treatment with a diet containing high iron dose and another iron-deficient. Methods: Female rats have received commercial food, formulated with different iron concentrations, from 2 weeks before mating to 15º day after delivery: Hyperferric – with 1,500 ppm of iron (n = 5); Control – with 35 ppm of iron (n = 5); Hypoferric – with 1 ppm of iron (n = 5). At the 15º Day after delivery, mammary glands were extracted and the expression of transferrin, lactoferrin and ferroportin was evaluated by western blotting technique. Results: Considering control-treatment results as being 100% pattern of the protein expression, the hiperferric diet has increased 17.82% the mean of transferrin expression, 27.50% of the lactoferrin and 63.79% of the ferroportin. The hipoferric diet has increased 13.33% the mean of transferrin expression, 44.59% of the lactoferrin and 20, 50% of the ferroportin. Conclusions: Both stimuli, hiperferric and hipoferric diet, have increased the expression of the 3 proteins related with iron transport. Under influence of hyperferric diet, remarkable increased was observed for ferroportin, protein related to iron exportation from the cell. Under influence of hypoferric diet a significant increased was observed for lactoferrin, one of the major iron-binding protein in milk.

Effect of angiotensin II and losartan on the phagocytic activity of peritoneal macrophages from Balb/C mice

Angiotensin II (AII), a product of rennin-angiotensin system, exerts an important role on the function of immune system cells. In this study, the effect of AII on the phagocytic activity of mouse peritoneal macrophages was assessed. Mice peritoneal macrophages were cultured for 48 h and the influence of different concentrations of AII (10-14 to 10-7 M) and/or losartan, 10-16 to 10-6 M), an AT1 angiotensin receptor antagonist, on phagocytic activity and superoxide anion production was determined. Dimethylthiazoldiphenyltetrazolium bromide reduction and the nucleic acid content were used to assess the cytotoxicity of losartan. A stimulatory effect on phagocytic activity (P < 0.05) was observed with 10-13 M and 10-12 M AII concentrations. The addition of losartan (up to10-14 M) to the cell cultures blocked (P < 0.001) the phagocytosis indicating the involvement of AT1 receptors. In contrast, superoxide anion production was not affected by AII or losartan. The existence of AT1 and AT2 receptors in peritoneal macrophages was demonstrated by immunofluorescence microscopy. These results support the hypothesis that AII receptors can modulate murine macrophage activity and phagocytosis, and suggest that AII may have a therapeutic role as an immunomodulatory agent in modifying the host resistance to infection.