Thymoquinone Abrogates Acrylamide-Induced Cerebellar Toxicity via Modulation of Nuclear Factor Erythroid 2-Related Factor 2/Nuclear Factor Kappa B Signaling, Oxidative Neuroinflammation, and Neuroapoptosis in Rats

Acrylamide (ACR) is an obligate human neurotoxicant ubiquitously produced and found in foods processed at high temperature. There is an increasing public health concern regarding its probable carcinogenic potential. Its prevailing toxicity mechanism is oxidative inflammation and apoptosis. Herein, we explored whether thymoquinone (TQ), a bioactive quinone in Nigella sativa seed, could mitigate ACR-induced cerebellar toxicity in rats. Our study design featured four rat groups: control, TQ (5 mg/kg bw), ACR (50 mg/kg bw), and TQ + ACR (5 mg/kg + 50 mg/kg). After 14 days of respective treatments, cerebellar homogenate was used to estimate acetylcholinesterase activity (AchE) activity, antioxidant enzymes (catalase [CAT], superoxide dismutase [SOD], and glutathione peroxidase [GPx]), malondialdehyde (MDA), inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-α, IL-4, and IL-10), nuclear factor kappa B (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2), caspase-3, and caspase-9. The level of DNA damage by fragmentation and histopathological lesions was also determined in the cerebellum. The rat exposure to ACR caused significant decreases in the cerebellar activities of AchE, CAT, SOD, and GPx, IL-4, IL-10, and expression of Nrf2, whereas the levels of MDA, IL-6, TNF-α, caspase-3, and caspase-9 were prominently increased compared with the control. ACR induced significant DNA fragments and cerebellar lesions when compared with the control. Contrarily, TQ treatment inhibited the depression of CAT, SOD, and GPx activities and reversed the MDA level and expression of Nrf2/NF-κB, cytokines, and caspases. These effects were confirmed by reduced DNA damage and cerebellar histopathological lesions in comparison with the ACR. TQ afforded neuroprotection via its antioxidant, anti-inflammatory, and antiapoptotic mechanisms in rats.