biochemical effects of dietary boron supplementation on immune response, steroid hormones and minerals metabolism

ABSTRACT

To investigate the effect of dietary boron [B] supplementation as sodium tetraborate on immune response, steroid hormones, and minerals metabolism in female albino rats. Eight groups each of eight female albino rats were divided as following-Group I [control group]; rats were feed on a standard basal diet. Group II; rats fed on basal diet+5 mg B/100 g diet. Group III; rats fed on basal diet+10 mg B/100 g diet. Group IV; rats fed on basal diet+15 mg B/l00 g diet. Group V; rats fed on basal diet+20 mg B/100 g diet. Group VI; rats fed on basal diet+25 mg B/100 g diet. Group VII; rats fed on basal diet+30 mg B/l00 g diet. Group VIII; rats fed on basal diet + 35 mg B/100 g diet for six weeks. The cell-mediated immune response was induced by an intradermal injection of 0.1 ml of phytohemagglutinin [PHA] [150 micro g/0.1 ml] in the flank region on both the right and left sides. Inflammatory response was measured as a change in skin thickness prior to and at 6, 12, 24 and 48h after PHA injection. In addition, serum levels of follicle stimulating hormone [FSH], luteinizing hormone [LH], progesterone, l7 beta-estradiol [E[2]], calcium, inorganic phosphorus, magnesium, total cholesterol, triacylglycerofs, and alkaline phosphatase [ALP] activity were measured. The immune response was increased by dietary boron supplementation at 6h alter injection compared to zero time. At 12h after injection the immune response had the lowest values in all rat groups fed diets containing different doses of dietary boron [5-35 mg B/100 g diet]. Serum levels of FSH and LH were not affected by boron supplementation While, serum concentration of 17 beta-estradiol increased significantly by increasing boron supplementation. In addition, serum levels of total cholesterol and tnacylglycerols were reduced in rats fed diets supplemented with 20-35 .mg B/100 g diet. In addition, serum levels of ALP activity was reduced in all treated groups compared to control group. Serum levels of calcium were increased' in rat groups fed diets containing 10-25.mg B/100 g diet, and then reduced as the supplementation of dietary boron increased [30 and 35 mg B/100 g diet]. A significant reduction was observed in serum inorganic phosphorus concentration in rats fed diets supplemented with boron at tested doses of 10-35 mg B/100 g diet. Dietary boron supplementation has regulatory effects on immune response increased estrogen levels, and maintenance of bone integrity, which may have a preventive effect on the development of osteoporosis