Cyanidin Alleviated CCl₄-Induced Acute Liver Injury by Regulating the Nrf2 and NF-κB Signaling Pathways

Acute liver injury has multiple causes and can result in liver failure. In this study, we evaluated the hepatoprotective ability of cyanidin (Cy) and investigated its associated mechanisms. Cy administration significantly and dose-dependently ameliorated acute liver injury induced by carbon tetrachloride (CCl₄). High-dose Cy showed effects comparable to those achieved by the positive control (silymarin). Severe oxidative stress and inflammatory responses in the liver tissue induced by CCl₄ were significantly mitigated by Cy supplementation. The total antioxidant capacity and the activity of superoxide dismutase, catalase, and glutathione peroxidase were increased and the content of malondialdehyde, lipid peroxide, tumor necrosis factor α, interleukin-1β, and interleukin-6 were decreased. Additionally, the Nrf2 and NF-κB signaling pathways, which regulate antioxidative and inflammatory responses, were analyzed using quantitative real-time polymerase chain reaction and western blot assay. Cy treatment not only increased Nrf2 transcription and expression but also decreased NF-κB signaling. Moreover, molecular docking simulation indicated that Cy had high affinity for Keap1 and NF-κB/p65, which may promote nuclear translocation of Nrf2 and inhibit that of NF-κB. In summary, Cy treatment exerted antioxidative and anti-inflammatory effects and ameliorated liver injury by increasing Nrf2 and inhibiting the NF-κB pathway, demonstrating the potential of Cy as a therapeutic agent in liver injury.