(searched for: doi:10.1016/j.fct.2021.112124)
Toxicology, Volume 458; https://doi.org/10.1016/j.tox.2021.152844
Aflatoxin B1 (AFB1), a naturally occurring mycotoxin, is present in human placenta and cord blood. AFB1 at concentrations found in contaminated food commodities (0.25 and 0.5 μM) did not alter the spontaneous movement, heart rate, hatchability, or morphology of embryonic zebrafish. However, around 86 % of 0.25 μM AFB1-treated embryos had livers of reduced size, and AFB1 disrupted the hepatocyte structures, according to histological analysis. Additionally, AFB1 treatment that begins at any stage before 72 h post-fertilization (hpf) effectively reduced the size of embryonic livers. In hepatic areas, AFB1 suppressed the expression of Hhex and Prox1, which are two critical transcriptional factors for initiating hepatoblast specification. KEGG analysis based on transcriptome profiling indicated that p53 signaling and apoptosis are the only observed pathways in AFB1-treated embryos. AFB1 at 0.5 μM significantly activated the expression of tp53, mdm2, puma, noxa, pidd1, and gadd45aa genes that are related to the p53 pathway and also that of baxa, casp 8 and casp 3a in the apoptotic process. TUNEL staining demonstrated that AFB1 triggered the apoptosis of embryonic hepatocytes in a dose-dependent manner. These results indicate that the deficiency of both hhex and prox1 as well as hepatocyte apoptosis via the p53-Puma/Noxa-Bax axis may contribute to the embryonic liver shrinkage that is caused by AFB1.
Food and Chemical Toxicology, Volume 154; https://doi.org/10.1016/j.fct.2021.112320
The aim of the present study was to explore the underlying mechanism of selenium (Se)-mediated detoxification of aflatoxin B1 (AFB1)-induced cardiotoxicity in chicks. A Se-deficient, corn-soybean meal-basal diet (36 μg Se/kg, BD) and three test diets (BD+1.0 mg AFB1/kg, 0.3 mg Se/kg, or 1.0 mg AFB1/kg+0.3 mg Se/kg) were used in a 3-wk 2 × 2 factorial design trial (n = 30 chicks/group). Dietary AFB1 led to induced (P < 0.05) serum creatine kinase and creatine kinase MB isoenzyme activities and heart histopathologic lesions. However, Se deficiency aggravated most of these alterations induced by AFB1. Moreover, mRNA levels of two ferroptosis activators (solute carrier family 11 Member 2 and transferrin) were upregulated (P < 0.05) in the AFB1-treated groups. Additionally, Se deficiency reduced (P < 0.05) glutathione peroxidase (GPX) 3 and thioredoxin reductase 3 mRNA and GPX activity but increased (P < 0.05) selenoprotein M and selenophosphate synthetase 2 mRNA in the heart in AFB1-administered groups. The in vitro study showed that Se alleviated (P < 0.05) AFB1-reduced cell viability and induced (P < 0.05) ROS and ferroptosis in H9C2 cardiac cells. It also downregulated (P < 0.05) two ferroptosis activators (long-chain acyl-CoA synthetase 4 and solute carrier family 11 Member 2) in the AFB1-treated groups in the H9C2 cells. In conclusion, this study illustrated that Se alleviates AFB1-induced cardiotoxicity and cardiomyocyte damage potentially related to the regulation of redox status, 4 selenoproteins, and ferroptosis-related signaling.
Toxins, Volume 13; https://doi.org/10.3390/toxins13060399
In the early 1960s the discovery of aflatoxins began when a total of 100,000 turkey poults died by hitherto unknown turkey “X” disease in England. The disease was associated with Brazilian groundnut meal affected by Aspergillus flavus. The toxin was named Aspergillus flavus toxin—aflatoxin. From the point of view of agriculture, aflatoxins show the utmost importance. Until now, a total of 20 aflatoxins have been described, with B1, B2, G1, and G2 aflatoxins being the most significant. Contamination by aflatoxins is a global health problem. Aflatoxins pose acutely toxic, teratogenic, immunosuppressive, carcinogenic, and teratogenic effects. Besides food insecurity and human health, aflatoxins affect humanity at different levels, such as social, economical, and political. Great emphasis is placed on aflatoxin mitigation using biocontrol methods. Thus, this review is focused on aflatoxins in terms of historical development, the principal milestones of aflatoxin research, and recent data on their toxicity and different ways of mitigation.