الفهرس 
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Abstract
Aflatoxins induce different toxicities in animals and human, the immune-toxic effect is one of them. Great efforts have been done to keep animals and human from the danger of aflatoxicosis.
The current study was designed to establish the immune-toxic effects of AFB1 via hematological and histological pictures as well as the treatment effect of copper albumin complex (II) in aflatoxicosed experimental rats.
Sixty albino rats were divided into 4 groups. Animals of G1 received no treatment (negative control group). Animals of G2 are exposed to AF B1 dissolved in corn oil as a vehicle at a dose of (400 microgram per k. g. body weight) day after day for 4 weeks. Animals of G3 are exposed to AFB1 and Copper albumin in a dose of 0.8 gm/kg b.w. given in dairy milk as a vehicle day after day for 4 weeks. Animals of G4 are exposed to Copper albumin only in a dose of 0.8 gm/kg b.w. At the end of the experiment, blood samples were collected from medial canthus of orbital cavity of rats for hematological examinations. Rats were sacrificed by cervical dislocation. Tissue specimens from spleen, liver,intestine, kidney and lymph nodes were collected from each rat. Three to five tissue blocks, 1x2 mm each, were taken from the organs immediately after dissecting the animals and fixed in 5 % cold glutaraldehyde for 72 hr for TEM examination and tissue specimens were fixed in 10%neutral buffered formalin for light microscope.
The clinical signs observed in rats received AFB1 only (G2) were depression,loss of appetite and weakness. Groups 3&4 were apparently normal.
The hematological parameters of aflatoxin exposed group demonstrated significantly decreased WBCs count in comparison with control one. Also lymphocytes, monocytes and neutrophils counts decreased. Erythrocytic count and HB concentration significantly increased in comparison with control animals. While group 3 and 4, animals showed non-significant changes in WBCs, lymphocytes, monocytes RBCs and hemoglobin concentration in comparison with control animals but group 4 showed increased neutrophils count in comparison with control animals.
The histopathological examination of liver from the aflatoxicosed animals showed hyperplasia of bile duct, presence of numerous fat globules and increased collagenous fibrous tissue in the portal area, around central vein and the presence of bundles of collagen fiber in Disse’s spaces. Transmission electron microscopy of the hepatic tissues of aflatoxicosed showed numerous variable size fat globules and lipofusin granules. Swelling with disintegration of the mitochondria, vaculation of the cytoplasm and indentation of some hepatic cell nuclei, activation of kupffer cells and presence of bundles of collagen fibers in Disse’s space were seen.
The lymphoid tissues revealed depletion of the lymphocytes in spleen and lymph nodes by light microscopical examination and wideness of intercellular spaces by T.E. In the protected group the germ center of the lymphoid follicle proliferating and become wide with increase population of lymphoid cell population mostly lymphocytes and lymphoblast. Depletion of the lymphoid cell population was seen in the payer’s patches with hyperplasia of the covering villous epithelium. T.E. micrograph of intestine belonging to aflatoxicosed group showed edema of the villous core and sub epithelial area with presence of numerous macrophages contain electrone dense lysosomes and hyperactive goblet cells which appeared overloaded with mucous globules. While T.E. micrograph of intestinal villous core showing presence of lymphoid cell, plasma cells, macrophages, esinophilic cells and inter-cellular edema.
The kidney of aflatoxicosed group showed congestion of the glomerular tufts, and interstitial blood vasculature and necrobiosis of the tubular epithelium by light microscopical examination, T.E.M. revealed congestion and thickening of the basement membrane of the blood capillaries, degeneration of the parietal epithelium of the glomerulus and urinary spaces were dilated and filled with proteinus material and cellular debris. While in protected group there were increases of mesangial cell of the glomerulus, the tubular epithelium showed normal appearance with presence of few deeply stained granules in its cytoplasm. The Bowman’s capsule showed normal appearance. The tubular epithelium contains large vesicular nucleus and cell organelles with few electron dense lysosomes.
It could be concluded that AFB1 act as immune-suppressive mycotoxin that causes leukopenia, lymphopenia, and monocytopenia. AFB1also act as a stress factor on the body which elevates cortisol level in the body leads to increase the number of erythrocytes and HBin the blood. Also aflatoxin leads to many histopathological changes on the lymphoid organ, kidney, liver and intestine. Copper albumin ameliorates these changes and could be used as immune-stimmulant and for treatment of immune-suppression.