Ferroptosis driven by radical oxidation of n-6 polyunsaturated fatty acids mediates acetaminophen-induced acute liver failure

Naoya Yamada,Yasunaru Sakuma,Junya Ito,Tadayoshi Karasawa,Hiroaki Kimura,Koichi Mizuta,Sachiko Watanabe,Ariunaa Sampilvanjil,Hiroshi Kuwata,Ryo Kamata,Masafumi Takahashi,Naohiro Sata,Takanori Komada,Kiyotaka Nakagawa,Shuntaro Hara

doi:10.1038/s41419-020-2334-2

Abstract

Acetaminophen (APAP) overdose is a common cause of drug-induced acute liver failure. Although hepatocyte cell death is considered to be the critical event in APAP-induced hepatotoxicity, the underlying mechanism remains unclear. Ferroptosis is a newly discovered type of cell death that is caused by a loss of cellular redox homeostasis. As glutathione (GSH) depletion triggers APAP-induced hepatotoxicity, we investigated the role of ferroptosis in a murine model of APAP-induced acute liver failure. APAP-induced hepatotoxicity (evaluated in terms of ALT, AST, and the histopathological score), lipid peroxidation (4-HNE and MDA), and upregulation of the ferroptosis maker PTGS2 mRNA were markedly prevented by the ferroptosis-specific inhibitor ferrostatin-1 (Fer-1). Fer-1 treatment also completely prevented mortality induced by high-dose APAP. Similarly, APAP-induced hepatotoxicity and lipid peroxidation were prevented by the iron chelator deferoxamine. Using mass spectrometry, we found that lipid peroxides derived from n-6 fatty acids, mainly arachidonic acid, were elevated by APAP, and that auto-oxidation is the predominant mechanism of APAP-derived lipid oxidation. APAP-induced hepatotoxicity was also prevented by genetic inhibition of acyl-CoA synthetase long-chain family member 4 or α-tocopherol supplementation. We found that ferroptosis is responsible for APAP-induced hepatocyte cell death. Our findings provide new insights into the mechanism of APAP-induced hepatotoxicity and suggest that ferroptosis is a potential therapeutic target for APAP-induced acute liver failure.

Highlights

Acetaminophen (APAP, known as paracetamol) is one of the most widely used analgesic or antipyretic drugs, and is safe when used at therapeutic doses
To rule out the possibility that Fer-1 could change APAP metabolism, we assessed the expression of cytochrome P450 2E1 (CYP2E1), a key enzyme to metabolize APAP to N-acetyl-p-benzoquinone imine (NAPQI), and showed that Fer-1 had no effect on hepatic expression of CYP2E1 mRNA and protein (Fig. 1e, f)
High-dose APAP-induced lethality was completely prevented by Fer-1; (2) APAP failed to induce the hepatic expression of cleaved caspase-3, receptor-interacting protein kinase 3 (RIPK3), and inflammatory markers at the early phase after APAP injection; (3) APAP-induced hepatotoxicity and lipid peroxidation were completely prevented by DFO; 4 Mass spectrometry revealed that lipid peroxides derived from n6 polyunsaturated fatty acid (PUFA) were elevated by APAP, and that auto-oxidation is the predominant mechanism of APAP-induced lipid oxidation; and (5) APAP-induced hepatotoxicity was prevented by genetic acyl-CoA synthetase long-chain family member 4 (ACSL4) inhibition or α-Toc supplementation

Summary

Introduction

Acetaminophen (APAP, known as paracetamol) is one of the most widely used analgesic or antipyretic drugs, and is safe when used at therapeutic doses. Overdose of APAP causes liver damage in a dosedependent manner, and in severe cases, results in acute liver failure[1]. Once acute liver failure occurs, liver transplantation is the only established life-saving procedure[2]. For decades, APAP-induced hepatotoxicity has NAPQI causes hepatotoxicity. Previous investigations have suggested that mitochondrial damage induced by unconjugated NAPQI has a key role in APAP-induced. Official journal of the Cell Death Differentiation Association. Yamada et al Cell Death and Disease (2020)11:144. Hepatocyte cell death is considered to be a critical event in APAP-induced hepatotoxicity, and contributes to the development of acute liver failure. The molecular mechanism of hepatocyte cell death in this process remains unclear[6,7,8]

Methods

Results

Conclusion