Sphingolipids are highly bioactive compounds that participate in the regulation of cell growth, differentiation, diverse cell functions, and apoptosis. They are present in both plant and animal foods in appreciable amounts, but little is known about their nutritional significance. Recent studies have shown that feeding
sphingomyelin to female CF1 mice treated with a colon
carcinogen (1,2-dimethylhydrazine) reduced the number of aberrant colonic crypt foci; longer-term feeding also affected the appearance of colonic
adenocarcinomas. Therefore, dietary
sphingolipids should be considered in studies of the relationships between diet and
cancer.
Sphingolipids have also surfaced as important factors in understanding the mechanism of action of a recently discovered family of
mycotoxins, termed
fumonisins.
Fumonisins are produced by fungi commonly found on maize and a few related foods, and their consumption can result in equine leukoencephalomalacia, porcine
pulmonary edema and a number of other diseases of veterinary animals and, perhaps, humans. A cellular target of
fumonisins is the
enzyme ceramide synthase, and disruption of
sphingolipid metabolism by
fumonisins has been established by studies with both cells in culture and animals that have consumed these toxic
mycotoxins. These findings underscore the ways in which
sphingolipids and agents that affect
sphingolipid utilization should be given consideration in selecting animal diets for nutritional and toxicological studies.