Related Experiment Video
Updated: Aug 11, 2025
Induction of Drug-Induced, Autoimmune Hepatitis in BALB/c Mice for the Study of Its Pathogenic Mechanisms
Published on: May 29, 2020
Acetaminophen-induced hepatotoxicity predominantly via inhibiting Nrf2 antioxidative pathway and activating
Xing-Ling Shen1, Yan-Na Guo1, Meng-Han Lu1
1School of Life Science and Engineering, Foshan University, Foshan 528225, China.
Abstract:
To explore the action time and molecular mechanism underlying the effect of acetaminophen (APAP) on liver injury. APAP was used to establish drug-induced liver injury (DILI) model in mice. Mice in the model group were intraperitoneally injected 300 mg/kg APAP for 6, 12, and 24 h respectively, and control group mice were given the same volume of normal saline. The mice were anesthetized through intravenous injection of sodium pentobarbital at 6, 12, and 24 h after APAP poisoning. Analysis of ALT, AST and ALP in serum, liver histopathological observation, oxidative damage and western blot were performed. The livers in APAP exposed mice were pale, smaller, with a rough texture, and poorly arranged cells. Lesions, large areas of hyperemia, inflammation, swelling, poorly cell arrangement, necrosis, and apoptosis of liver cells were obvious in the liver tissue sections. Serum ALT, AST and ALP levels were significantly enhanced at 12 h of APAP adminstration mice than that of in control group mice (P＜0.05). The histopathological alterations and proinflammatory cytokines (IL-1β, TNF-α and IL-6) levels were most severe at 12 h of APAP-induced hepatotoxicity. APAP treatment induced oxidative stress by decreasing hepatic activities of superoxide dismutase (SOD) and glutathione (GSH) (P＜0.05), and enhancing malondialdehyde (MDA) content (P＜0.05). Moreover, APAP inhibited erythroid 2-related factor 2 (Nrf2) antioxidative pathway with decreased of Nrf2 and HO-1 proteins levels. Furthermore, APAP aggravated the activation of NLRP3 inflammasome by increasing of NLRP3, caspase-1, ASC, IL-1β and IL-18 proteins levels. Finally, APAP further significantly activated the toll-like receptor 4 (TLR4), nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) signaling pathways. This study demonstrated that APAP-induced hepatotoxicity by inhibiting of Nrf2 antioxidative pathway and promoting TLR4-NF-κB-MAPK inflammatory response and NLRP3 inflammasome activation.
Insights
Acetaminophen (APAP) causes liver injury by inhibiting the Nrf2 antioxidant pathway and activating inflammatory pathways like TLR4-NF-κB-MAPK and NLRP3 inflammasome. This study details the molecular mechanisms and timing of APAP-induced hepatotoxicity.
Area of Science:
- Hepatology
- Toxicology
- Molecular Biology
Background:
- Acetaminophen (APAP) is a common analgesic with potential for drug-induced liver injury (DILI).
- Understanding the precise molecular mechanisms and temporal progression of APAP-induced hepatotoxicity is crucial for developing effective interventions.
Purpose of the Study:
- To elucidate the action time and molecular mechanisms of acetaminophen (APAP) in causing liver injury.
- To investigate the role of oxidative stress, inflammatory pathways, and inflammasome activation in APAP-induced hepatotoxicity.
Main Methods:
- Establishment of a DILI model in mice using APAP (300 mg/kg).
- Assessment of liver injury markers (ALT, AST, ALP), histopathology, oxidative stress (SOD, GSH, MDA), and protein expression via Western blot at 6, 12, and 24 hours post-APAP administration.
- Analysis of key signaling pathways including Nrf2, NLRP3 inflammasome, TLR4, NF-κB, and MAPKs.
Main Results:
- APAP exposure led to significant liver damage, characterized by altered liver texture, inflammation, necrosis, and apoptosis.
- Serum enzyme levels (ALT, AST, ALP) and pro-inflammatory cytokines (IL-1β, TNF-α, IL-6) were significantly elevated at 12 hours.
- APAP induced oxidative stress by reducing SOD and GSH, increasing MDA, inhibiting the Nrf2/HO-1 pathway, and activating the NLRP3 inflammasome and TLR4-NF-κB-MAPK signaling cascades.
Conclusions:
- APAP-induced hepatotoxicity is a time-dependent process, with significant molecular and pathological changes evident by 12 hours.
- The mechanism involves the suppression of the Nrf2 antioxidative pathway and the promotion of inflammatory responses via TLR4-NF-κB-MAPK and NLRP3 inflammasome activation.
- These findings provide critical insights into the molecular pathogenesis of APAP-induced liver injury.
