comparative histological and toxicological study on the protective effect of casein versus retinol on N-Butyl Benzene sulphonamide-induced toxicity in adrenal cortex of albino rats

ABSTRACT

N-butyl benzene sulphonamide [NBBS] is a plasticizer used in production of plastic resins and as a starting agent in the synthesis of agricultural fungicides. Workers engaged in these industries and consumers of their products are at an increased risk of neurodegenerative intoxication. Nevertheless, other possible toxic effects of NBBS have not yet been studied. The aim of the study was to evaluate the possible toxic effect of NBBS on adrenal cortex of albino rats and the protective role of dietary casein versus retinol [vitamin A]. The study was conducted on forty two adult male albino rats, divided into four groups a control group [further subdivided into; a negative subgroup receiving no treatment and three positive controls given olive oil, retinol or casein], NBBS-treated group and two protected groups receiving NBBS with either retinol or casein for 28 days. Blood samples were collected for estimation of serum corticosterone level and specimens from the adrenal cortex were processed and subjected to light and ultrastructural microscopic examination. Significant reduction of serum corticosterone level was noticed in NBBS-intoxicated group, while rats protected with casein or vitamin A showed restoration of serum corticosterone to nearly normal control values. On the other hand, light and ultrastructural examination revealed marked affection of the adrenal cortex of NBBS-intoxicated rats, with thickened connective tissue capsule and more affection of zona glomerulosa and fasiculata than zona reticularis. The pronounced feature of zona glomerulosa was hyperplasia and disorganized archades together with multiple lipid droplets and microvillous projections in some cells. Zona fasiculata showed disorganized columns. Some cells revealed excessive lipid droplets and myelin figures, while others showed nuclear pyknosis. Numerous bizarre mitochondria were demonstrated in some cells. Few cells showed disturbed mitochondrial cristae and rough endoplasmic reticulunt dilatation. Most of zona reticularis cells appeared normal, however, few cells revealed irregular nuclei and mitochondrial pleomorphism. Protection with vitamin A and casein was successful in ameliorating the biochemical and histological changes induced by NBBS, where increased serum corticosterone level was recorded approaching control values, with restoration of nearly normal histological structure of all three zones of the adrenal cortex, however casein was more effective in reversing NBBS toxic effects. The plasticizer NBBS showed significant adreno-cortical toxicity. The use of antioxidants especially casein was efficient against NBBS toxic effects. Restriction of the use of plastic packaging for foods, pharmaceuticals and other biological products is recommended to avoid leaching of plasticizers resulting in toxic exposure