Aflatoxin B1 Toxicity in Animal Models: Biomarker-Guided Mechanisms, Systemic Injury, and Precision Mitigation Strategies
Aflatoxin B1 (AFB1) is a highly toxic mycotoxin which can be carried over into animal products and cause deterioration of livestock productivity when fed to livestock and wildlife. This review proposes a biomarker-guided framework for improving the early assessment of AFB1 exposure and toxicological responses in animal models. Oral exposure leads to the absorption of AFB1, which is bioactivated in the liver to the reactive AFB1-exo-8,9-epoxide that causes DNA and protein adduct formation, inflammation, mitochondrial apoptosis, and other effects. Cytochrome P450 activation and glutathione-dependent detoxification are in balance in determining susceptibility species, and this balance is different for poultry, pigs, ruminants, and rodents. In addition to traditional liver enzymes and histopathology, we highlight mechanistically informative biomarkers such as metabolites of aflatoxin, DNA and albumin adduct, lipid peroxidation products, antioxidant indices, cytokines, apoptotic markers, as well as signals involved in the Nrf2/NFκB pathway. AFB1 also damages the integrity of the intestinal barrier, the maintenance of the intestinal gut microbiota, reproductive function, growth performance, and development, thus creating a gut–liver-systemic toxic cascade. Finally, an assessment of stage-targeted interventions such as aluminosilicate binders, adsorbents derived from yeast, probiotics and nano-enabled interventions is conducted as viable tools for the reduction in exposure and injury. This review offers targeted mitigation strategies for early diagnosis of aflatoxicosis in animal production systems based on a biomarker approach.