An Evaluation of the Metabolic Basis of Aflatoxin B 1 Toxicity by Using Buffalo Granulocytes and Agranulocytes In Vitro

Abstract

This study was aimed at monitoring cytotoxic changes in buffalo leukocyte subpopulations exposed to aflatoxin B₁ (AFB₁), since no such information is available for this species. The effects of AFB₁ on glutathione (GSH) S-transferase, Ca²⁺Mg²⁺ATPase and protein synthesis in leukocyte subpopulations, namely, mononuclear (MN) cells and polymorphonuclear (PMN) cells isolated from the blood of the domestic buffalo (Bos bubalis), were studied. The cells were separated by using Ficoll-Paque and incubated in the presence of AFB₁. GSH S-transferase activity was found to increase in cells exposed to AFB₁, but there was no difference in activity between MN and PMN cells. PMN cell ATPase activity increased after AFB₁ treatment, whereas no such effect was observed in the MN cells, which showed higher basal levels of ATPase activity. In the presence of AFB₁, all the cells showed significant decreases in ¹⁴C-leucine incorporation, but the MN cells showed higher ¹⁴C-leucine incorporation than the PMN cells. Nevertheless, both cell types were affected by AFB₁ and participated in its detoxification. There was also an appreciable decrease in the release of myeloperoxidase by activated PMN cells in the presence of AFB₁.

Keywords

agranulocytes glutathione S-transferase granulocytes myeloperoxidase

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