In vivo and in vitro α-amanitin metabolism studies using molecular networking

Amanitin poisonings are among the most life-threatening mushroom poisonings, and are mainly caused by the genus Amanita. Hepatotoxicity is the hallmark of amanitins, powerful toxins contained in these mushrooms, and can require liver transplant. Among amatoxins, alpha-amanitin is the most studied. However, the hypothesis of a possible metabolism of amanitins is still controversial in this pathophysiology. Therefore, there is a need of clarification using cutting-edge tools allowing metabolism study. Molecular network has emerged as powerful tool allowing metabolism study through organization and representation of untargeted tandem mass spectrometry (MS/MS) data in a graphical form. The aim of this study is to investigate amanitin metabolism using molecular networking. In vivo (four positive amanitin urine samples) and in vitro (differentiated HepaRG cells supernatant incubated with alpha-amanitin 2 mM for 24 h) samples were extracted and analyzed by LC-HRMS/MS using a Q ExactiveTM Orbitrap mass spectrometer. Using molecular networking on both in vitro and in vivo, we have demonstrated that alpha-amanitin does not undergo metabolism in human. Thus, we provide solid evidence that a possible production of amanitin metabolites cannot be involved in its toxicity pathways. These findings can help to settle the debate on amanitin metabolism and toxicity. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Amanitin poisonings caused by the genus Amanita are some of the most life-threatening mushroom poisonings, mainly characterized by hepatotoxicity due to the powerful toxins contained in these mushrooms. Through molecular networking, it has been demonstrated that alpha-amanitin does not undergo metabolism in humans, providing solid evidence that amanitin metabolites are not involved in its toxicity pathways. These findings can help to settle the debate on amanitin metabolism and toxicity.