SUBCHRONIC TOXICITY OF FUMONISIN B-1 TO MALE AND FEMALE RATS

Fumonisins are a class of mycotoxins produced by Fusarium moniliforme and other Fusarium spp. These compounds are widely distributed in corn . Equine leukoencephalomalacia, pulmonary oedema in swine, and nephrot oxicity, hepatotoxicity and liver cancer in male rats, all of which ar e caused by toxic F. moniliforme, have been experimentally reproduced using fumisin B-1 (FB1) (ca 90-94% purity). To investigate the effect of purified (greater than or equal to 99% purity) FB1, to compare the effects of FB1 in males and females, and to obtain dose-response infor mation for FB1, three rats per sex were fed diets containing 0, 15, 50 or 150 FB1 for 4 weeks. Serum chemical, organ weight and histopatholo gical evidence showed that 150 mg/kg FB1 was hepatotoxic in both sexes . Nephrosis was found in males fed greater than or equal to 15 mg/kg a nd females fed greater than or equal to 50 mg/kg FB1. Altered sphingol ipid profiles, specifically increased free sphinganine concentrations and increased sphinganine: sphingosine ratios, were found in the liver , kidney, serum and urine of FB1-fed rats. These findings support the hypothesis that in vivo toxicity caused by fumonisins may result from altered sphingolipid metabolism.