EFFECT OF DIETARY SELENIUM AND VITAMIN-E ON THE BIOMECHANICAL PROPERTIES OF RABBIT BONES

It is generally agreed that combined deficiency of selenium and vitami n E leads to several abnormalities including Kashin-Beck disease which is an endemic and chronic degenerative osteoarthrosis. The abnormalit ies can be reversed by the administration of various forms of selenium and vitamin E. The present study was designed to investigate the effe cts of dietary selenium and vitamin E on bone tissue and on the biomec hanical properties of bone. Young rabbits of both sexes were fed with either a selenium-and vitamin E-adequate diet (control group), or a se lenium-and vitamin E-deficient diet or a selenium-excess diet, The sel enium-deficient diet resulted in a significant decrease in plasma sele nium level and the selenium-excess diet resulted in a significant incr ease in the plasma selenium level with respect to the corresponding co ntrol values (p < 0.05). The diets did not affect the blood cell count s considerably but erythrocyte glutathione peroxidase activity increas ed (decreased) relatively when the plasma selenium level increased (de creased) (p < 0.05). The light microscopic investigations of the bone tissues of the two experimental groups indicate that the findings of t he present work are compatible with osteomalacia. The biomechanical pr operties of the bones from the three groups were determined; experimen tally with bending tests, Both the Se- and vitamin E-deficient diet an d the Se-excess diet decreased the biomechanical strength-of the bones significantly while the bones belonging to the control group always h ad the largest modulus of elasticity (p < 0.05).