ADAMTS13 Improves Hepatic Platelet Accumulation in Pyrrolizidine Alkaloids-induced Liver Injury

Background and Aims Pyrrolizidine alkaloids (PAs), widely distributed in plants, are known to induce liver failure. Hepatic platelet accumulation has been reported during the progression of PA-induced liver injury (PA-ILI). This study aimed to investigate the mechanisms underlying platelet accumulation in PA-ILI. Methods Cases of PA-ILI, non-PA-ILI, and control subjects were collected from patients hospitalized at Zhongshan Hospital, Fudan University (Shanghai, China) between 2012 and 2019. A mouse model of PA-ILI was established using monocrotaline administration. Liver RNA sequencing was performed, and gene interactions were analyzed using the Search Tool for the Retrieval of Interacting Genes/Proteins online database. Low-molecular-weight heparin and recombinant a disintegrin and metalloproteinase with a thrombospondin type I motif member 13 (ADAMTS13) were applied. The necrotic liver area, hepatic platelet accumulation, and von Willebrand factor (VWF) deposition were examined using hematoxylin and eosin staining and immunofluorescence assay. Results Hepatic platelet accumulation, necrotic area expansion, and increased VWF expression were observed in both PA-ILI patients and mice. The Search Tool for the Retrieval of Interacting Genes/Proteins database indicated that ADAMTS13 regulates VWF expression and was differentially expressed in the livers of PA-ILI mice. Plasma and hepatic ADAMTS13 levels were significantly downregulated in both PA-ILI patients and mice. Systemic administration of recombinant ADAMTS13 decreased hepatic platelet accumulation, downregulated VWF expression, and mitigated mouse hepatic necrosis. Conclusions Hepatic platelet accumulation in PA-ILI was confirmed in both patients and mice. Deficiency of ADAMTS13 plays a critical role in platelet accumulation in PA-ILI, suggesting that ADAMTS13 could be a potential therapeutic target for this condition.