Effect of Subchronic Aflatoxin Exposure on Growth and Progression of Ehrlich's Ascites Tumor in Mice

Abstract

The present investigation was undertaken to assess whether aflatoxin B1 (AFB1) has any modulatory effect on the growth and progression of Ehrlich's ascites tumor (EAT) in mice or not. Male Swiss albino mice were treated with 0, 70, 350 and 700 micrograms AFB1/kg body weight in 0.2 ml corn oil on alternate days, orally, for two weeks. Treated animals were challenged with 1 x 10(6) cells of Ehrlich's ascites tumor. Animals were monitored for the appearance of palpable tumor, body weight gain as a measure of tumor burden, mortality profile and tumor cell population. Some parameters of cell mediated immunity (CMI), humoral immunity and non-specific immunity were also studied in aflatoxin treated animals in order to find out the mechanism of action of AFB1 on host immunity. It was observed that AFB1 treatment resulted in an early appearance of tumor, enhanced mortality, appreciable increase in body weight gain and EAT cell population following tumor challenge, in comparison with the control animals. Aflatoxin treatment caused suppression of CMI including an impairment of macrophage function, while humoral immunity was not much affected. It may be concluded that impaired CMI and macrophage function might be contributing to the increased growth of EAT in the AFB1 treated animals. Our findings may be relevant in that when a host is exposed to aflatoxins concomitantly with other carcinogens and cancer causing situations.

Immunomodulatory activity of biopolymeric fraction RLJ-NE-205 from Picrorhiza kurroa

“…Cunningham chambers were prepared using a glass slide, coverslips and doubled-sided tape. The chambers were loaded with a known volume of assay mixture, sealed with xylene and incubated at 37°C for 1 h. The plaques were counted under a light microscope and expressed as PFC per 10 6 spleen cells [8].…”

Aflatoxin induces depletion of activities of phase I biotransformation enzymes in growing rats

“…Our studies have shown that aflatoxin has a profound immunosuppressive effect in growing animals (9,10). The macrophage defence mechanism and cell mediated immunity have been found to be very sensitive to aflatoxin toxicity in growing animals (9)(10)(11).…”

“…The prevailing conditions of malnourishment may also aggravate the toxic and carcinogenic potentials of aflatoxin in a developing host (34,35). Our earlier observations have already shown that aflatoxin may enhance susceptibility of a host towards tumor challenge (11). A developing host under such circumstances may not only be deficient in metabolizing and disposing of several xenobiotics, but also be susceptible to various types of infections and malignancies due to the immunosuppressive effects of aflatoxin (9,11).…”

Immunomodulatory activity of Nerium indicum through inhibition of nitric oxide and cyclooxygenase activity and modulation of TH1/TH2 cytokine balance in murine splenic lymphocytes

“…Plaque forming cell (PFC) assay A previously described method (Raisuddin et al 1991) was followed with slight modifications to perform the PFC assay. Briefly, 24 Swiss albino mice were divided into 4 groups (n = 6).…”