The effects of ochratoxin A on liver metabolism

Abstract

This review summarizes the main toxic effect of ochratoxin A (OTA) on liver metabolism. This contaminant is a mycotoxin that can be found in raw materials (cereals, coffee, cocoa, spices or grapewine), in processed foods (bread and other bakery products) and, if animals are fed with contaminated feedstuffs, in pork meat. Kidney is a well-known target of OTA, although several findings suggest that liver metabolism can be affected too. OTA intake reduces, in a dose-dependent manner, the synthesis of albumin, while the concomitant increase in transaminases (ALT, ASP) and alkaline phosphatase is in agreement with the hypothesis of liver damage induced by OTA. Feeding animals with OTA-contaminated feeds has significant prooxidative effects that cause a reduction in anti-oxidative defences and an increase in malondialdehyde formation. Experiments on human liver cells support the hypothesis of an inflammatory effect of OTA mediated by TNF-α. An upregulation of apoptosis has also been detected in hepatic cells after OTA treatment, which leads to a higher rate of cell death and to a reduction of liver activity. All these findings suggest that OTA can have a toxic effect on the liver too and for this reason we should pay attention to liver toxicity of OTA in the risk assessment for this mycotoxin.