Selenium deficiency-induced growth retardation is associated with an impaired bone metabolism and osteopenia

Although the importance of selenium for bone metabolism is unknown, some clinical conditions such as Kashin-Beck osteoarthropathy have been associated with selenium deficiency. Although selenium deficiency induces growth retardation in rats, it has not been established whether this growth inhibition is associated with changes in bone metabolism. We investigated the effect of selenium deficiency on bone metabolism in growing male rats fed a selenium-deficient diet for two generations (Se-). In Se- rats, erythrocyte glutathione peroxidase activity and plasma selenium concentration were strongly reduced compared with pair-fed selenium-adequate rats (Se+). Weight and tail length were reduced by 31% and 13% in the Se- rats, respectively (p < 0.001). The Se- diet was associated with a 68% reduction of pituitary growth hormone (GH; p = 0.01) and a 50% reduction of plasma insulin-like growth factor I (IGF-I, p < 0.001). Plasma calcium was lower and urinary calcium concentration was greater in Se- rats. This group had a 2-fold increase in parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D-3 [1,25(OH)(2)D-3] in plasma. Plasma osteocalcin and urinary deoxypyridoline were reduced by 25% and 57% in the Se- rats (P < 0.001). Selenium deficiency resulted in a 23% and 21% reduction in bone mineral density (BMD) of the femur and tibia (p < 0.001) and this effect persisted after adjustment for weight in a linear regression model. A 43% reduction in trabecular bone volume of the femoral metaphysis (p < 0.001) was found in Se- rats. This experimental study shows that growth retardation induced by selenium deficiency is associated with impaired bone metabolism and osteopenia in second-generation selenium-deficient rats.