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Jia-Sheng Wang and John Groopman. DNA damage by mycotoxins. Mutation Research 1999; 424:167-81. AND Yan Liu and Felica Wu. Global burden of aflatoxin-induced hepatocellular carcinoma: a risk assessment/ Environmental Health Perspectives 2010;118:818-24.
Worldwide, consumption of aflatoxin contaminated foods causes an estimated 25,200 to 155,000 liver cancer deaths annually. Aflatoxins are also associated with significantly elevated risk of lung cancer. Aflatoxins are frequent contaminants in many foods, especially on peanuts and grains. Storage of peanuts and grains in overly wet conditions can greatly increase levels of alfatoxin contamination. Aflatoxin contamination is a huge problem in China, India, and many African nations. Aflatoxins can increase risk of cancer by many ways including: binding to DNA to form DNA adducts, and increasing risks of sister chromosome exchange, unscheduled DNA synthesis, and formation of micronuclei. The aflatoxin-DNA adducts can remain stable for weeks to months and cause toxic effects over a long period of time. The aflatoxin–DNA adducts can increase activation of onogenes- which are genes involved in the start of cancer formation. Human and animal studies have also reported that consuming optimum amounts of certain nutrients such as protein and anti-oxidant vitamins (A, C, D, E) can reduce the toxic effect of aflatoxins. Ochratoxins are produced by Aspergillus and Pencillium molds. Ochratoxins are toxic to the urinary tract. Human and animal exposure to ochratoxin can increase risk of cancer to the kidney, bladder, and ureter. Ochratoxins also form toxic adducts with the DNA in the cell which can disrupt normal DNA replication in the cell. Sterimatocystin is produced by some species of Aspergillus, Penicillium and Bipolaris. Sterigmatocystin causes toxic DNA adducts, is associated with increased risk of liver cancer, and depresses the immune system. Zearalenone is produced primarily by Fusarium molds. It has been shown to cause liver and pituitary cancers in lab mice. Zearalenone also produces toxic DNA adducts which increases risk of sister chromatid exchange, chromosomal changes and DNA polyploidy (extra sets of chromosomes).
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