Kidney toxicity and transcriptome analyses of male ICR mice acutely exposed to the mushroom toxin α-amanitin

Abstract

Amatoxins are responsible for most fatal mushroom poisoning cases, as it causes both hepatotoxicity and nephrotoxicity. However, studies on amatoxin nephrotoxicity are limited. Here, we investigated nephrotoxicity over 4 days and nephrotoxicity/hepatotoxicity over 14 days in mice. The organ weight ratio, serological indices, and tissue histology results indicated that a nephrotoxicity mouse model was established with two stages: (1) no apparent effects within 24 h; and (2) the appearance of adverse effects, with gradual worsening within 2-14 days. For each stage, the kidney transcriptome revealed patterns of differential mRNA expression and significant pathway changes, and Western blot analysis verified the expression of key proteins. Amanitin-induced nephrotoxicity was directly related to RNA polymerase II because mRNA levels decreased, RNA polymerase II-related pathways were significantly enriched at the transcription level, and RNA polymerase II protein was degraded in the early poisoning stage. In the late stage, nephrotoxicity was more severe than hepatotoxicity. This is likely associated with inflammation because inflammation-related pathways were significantly enriched and NF-κB activation was increased in the kidney.

Keywords: Kidney; Mushroom poisoning; RNA polymerase II (RNAP II); Transcriptome; α-Amanitin.