Etemadi, Y. | Search bioRxiv

bioRxiv2026

Differentiating Hepatic and Renal Toxicity Reveals CYP-Independent Mechanisms of Acetaminophen-Induced Acute Kidney Injury

Acetaminophen (APAP) overdose is the leading cause of acute liver failure (ALF), with acute kidney injury (AKI) contributing substantially to morbidity and mortality in those patients. To determine whether APAP-induced AKI depends on hepatic CYP2E1-mediated bioactivation, we used CYP2E1^flox/flox^ mice treated with AAV8-TBG-Cre to selectively delete hepatic CYP2E1 while preserving renal metabolism. Male and female mice received APAP (600 mg/kg) and were evaluated up to 48 hours for liver and kidney injury. Liver-specific CYP2E1 deletion reduced APAP hepatotoxicity, confirming the absence of hepatic NAPQI formation. Despite this protection, both male and female mice treated with AAV8-TBG-Cre and APAP developed progressive renal injury, with marked increases in blood urea nitrogen (BUN) and creatinine, tubular vacuolation, and strong induction of KIM-1 and osteopontin, along with apoptotic cell death at 48 hours. Notably, female mice, lacking renal CYP2E1 and displaying no detectable renal protein adducts, still progressed to AKI, demonstrating that kidney injury can occur through CYP-independent mechanisms. Given that APAP-induced AKI is a delayed injury, we further considered p-aminophenol (PAP), a deacetylation product of APAP, as a potential CYP-independent contributor. These findings support the concept that non-CYP pathways, including PAP formation, may contribute to kidney injury during the later phase of toxicity, although this pathway likely represents only one component of a multifactorial injury process. Together, these results demonstrate that APAP-induced AKI is a kidney-intrinsic process that can develop independently of both hepatic and renal CYP2E1 activity, emphasizing the need for kidney-specific therapeutic strategies for preventing APAP-induced renal injury.

pharmacology and toxicology↗

bioRxiv2026

Psilocybin Attenuates Cortical Representations of Aversion in the Mouse Auditory Cortex

Psilocybin can produce sustained benefits in affective and trauma-related disorders, yet if and how it reshapes sensory representations of learned valence associations remains largely unclear. To address this, we used longitudinal two-photon calcium imaging in awake C57BL/6 mice to examine how psilocybin modulates layer 2/3 auditory cortex activity at single-cell and population levels. Evoked responses were measured for tones with or without prior associations with valenced stimuli, as well as for the valenced stimuli themselves. Most responsive neurons were selective for tones alone, while distinct subsets responded exclusively to reward or aversive stimuli, and a smaller population encoded both. Psilocybin selectively reduced responses to aversive stimuli and earlier-established aversive-associated tones, without affecting aversive association, reward responses, or responses to newly aversive-associated tones. At the population level, psilocybin acutely increased coordination across tone-responsive neurons, while later reducing it selectively among neurons encoding the aversive-associated tone. These results demonstrate that psilocybin preferentially dampens well consolidated aversive sensory representations in auditory cortex, rather than fresh associations, without broadly affecting auditory processing or new aversive learning.

neuroscience↗