The synthetic cannabinoid CUMYL-4CN-BINACA induces hepatic injury in rats via oxidative stress, NF-κB activation, Nrf2 suppression, EDEM-1, ER stress-mediated apoptotic pathways.

Synthetic cannabinoids (SCs), particularly CUMYL-4CN-BINACA (C-4CN-B), are highly potent psychoactive substances linked to systemic toxicity, including liver injury. This study evaluated the dose-dependent hepatotoxic effects of C-4CN-B and the underlying molecular pathways in male Sprague Dawley rats. Thirty-two animals were divided into four groups (n = 8): a control group receiving vehicle (2 % ethanol, 2 % Tween 80, 96 % saline) and three treatment groups administered C-4CN-B intraperitoneally at 0.25, 0.5, or 1.0 mg/kg for 14 days. Liver function markers (ALT, AST, ALP) were analyzed biochemically. Oxidative stress indicators, including malondialdehyde (MDA) and reduced glutathione (GSH), were measured, while antioxidant enzymes (SOD, CAT, GPx) and apoptosis/inflammation-related proteins (Bax, Bcl-2, Caspase-3, NF-κB, TNF-α, IL-1β) were assessed via ELISA. Western blotting detected Keap-1, TLR-4, NF-κB, TNF-α, IL-6, IL-1β, HO-1, and Nrf2 expression. RT-qPCR profiled genes regulating oxidative and ER stress, including XBP-1, CHOP, GRP78, ATF4, EDEM1, Nrf2, and HO-1. C-4CN-B exposure caused dose-related increases in liver enzymes and MDA, alongside depletion of GSH and antioxidant enzymes. Pro-inflammatory cytokines and apoptotic markers were markedly upregulated. Molecular analyses showed NF-κB/TLR-4 activation, suppression of Nrf2/HO-1, and induction of ER stress genes. These findings indicate that C-4CN-B induces hepatotoxicity through oxidative stress, ER stress, and inflammatory-apoptotic signaling.