Sterigmatocystin: Occurrence, toxicity and molecular mechanisms of action - A review

Abstract

The mycotoxin sterigmatocystin (STE) is produced mainly by Aspergillus fungi. It has been reported to occur in grains and grain-based products, cheese, coffee, spices and beer. The STE is a known biogenic precursor of aflatoxin B1, sharing with it several structural and biological similarities. The STE has been shown to be hepatotoxic and nephrotoxic in animals and it has been classified as possible human carcinogen (group 2B) by IARC. The STE has been reported to cause a marked decrease in cell proliferation in different mammalian cells. Data available on literature suggest that the cellular mechanisms underlying STE-induced toxicity include the induction of oxidative stress, mitochondrial dysfunction, apoptosis, cell cycle arrest, as well as alteration of immune system function and activation of different signalling pathways. Moreover, STE resulted to be genotoxic, being able to form DNA-adducts and induce DNA damage. Despite its strong cytotoxicity, no risk assessments have been still carried out by authorities due to the lack of toxicity data, so research on STE toxicological impact is still going on. This review reports information available regarding STE toxicity and its related mechanisms of action with the aim of updating information regarding last researches on this mycotoxin.

Keywords: Biosynthetic and metabolic pathway; Mechanisms of action; Occurrence in food; Sterigmatocystin; Toxicity.