Aflatoxin B1 Increases Soluble Epoxide Hydrolase in the Brain and Induces Neuroinflammation and Dopaminergic Neurotoxicity

Aflatoxin B1 exposure deteriorates immune abnormalities in a BTBR T+ Itpr3tf/J mouse model of autism by increasing inflammatory mediators' production in CD19-expressing cells

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by deficiencies in communication, repetitive and stereotyped behavioral patterns, and difficulties in reciprocal social engagement. The presence of immunological dysfunction in ASD has been well established. Aflatoxin B1 (AFB1) is a prevalent mycotoxin found in food and feed, causing immune toxicity and hepatotoxicity. AFB1 is significantly elevated in several regions around the globe. Existing research indicates that prolonged exposure to AFB1 results in neurological problems. The BTBR T+ Itpr3tf/J (BTBR) mice, which were used as an autism model, exhibit the primary behavioral traits that define ASD, such as repeated, stereotyped behaviors and impaired social interactions. The main objective of this work was to assess the toxic impact of AFB1 in BTBR mice. This work aimed to examine the effects of AFB1 on the expression of Notch-1, IL-6, MCP-1, iNOS, GM-CSF, and NF-κB p65 by CD19+ B cells in the spleen of the BTBR using flow cytometry. We also verified the impact of AFB1 exposure on the mRNA expression levels of Notch-1, IL-6, MCP-1, iNOS, GM-CSF, and NF-κB p65 in the brain of BTBR mice using real-time PCR. The findings of our study showed that the mice treated with AFB1 in the BTBR group exhibited a substantial increase in the presence of CD19+Notch-1+, CD19+IL-6+, CD19+MCP-1+, CD19+iNOS+, CD19+GM-CSF+, and CD19+NF-κB p65+ compared to the mice in the BTBR group that were treated with saline. Our findings also confirmed that administering AFB1 to BTBR mice leads to elevated mRNA expression levels of Notch-1, IL-6, MCP-1, iNOS, GM-CSF, and NF-κB p65 in the brain, in comparison to BTBR mice treated with saline. The data highlight that exposure to AFB1 worsens immunological abnormalities by increasing the expression of inflammatory mediators in BTBR mice.

Aflatoxin B1-induced redox imbalance in the hippocampus and cerebral cortex of male Wistar rats is accompanied by altered cholinergic, indoleaminergic, and purinergic pathways: Abatement by dietary rutin

The neurotoxic impact of dietary exposure to aflatoxin B1 (AFB1) is well documented in experimental studies. Rutin is a phytochemical with prominent anti-inflammatory and antioxidant activities. There is an information gap on the influence of rutin on AFB1-induced neurotoxicity. This study investigated the influence of rutin on neurobehavioral and biochemical abnormalities in male Wistar rats (six weeks old) orally treated with AFB1 (0.75, and 1.5 mg/kg body weight) or co-administered with rutin (50 mg/kg) for 30 uninterrupted days. Results indicate that AFB1-induced depression-like behavior by Tail Suspension Test (TST) and cognitive impairment by Y-maze was abated following rutin co-administration. Abatement of AFB1-induced decreases in acetylcholinesterase (AChE) activity, and increased antioxidant status, by rutin was accompanied by a marked reduction in oxidative stress markers and increased hydrolysis of the purinergic molecules in the cerebral cortex and hippocampus of rats. Additionally, rutin co-treatment abrogated AFB1-mediated elevation of interleukin-6 (IL-6), nitric oxide (NO) levels, and activity of myeloperoxidase (MPO). Correspondingly, rutin co-treatment lowered the activity and immunocontent of immunosuppressive indoleamine 2, 3-dioxygenase (IDO). Further, rutin co-treatment prevented histological injuries in the cerebral cortex and hippocampus. In conclusion, abatement of AFB1-induced neurobehavioral abnormalities by rutin involves the mechanisms of anti-inflammatory, antioxidant, and regulation of cholinergic, purinergic, and indoleaminergic pathways in rats.