Mycotoxins: Emerging toxic mechanisms, and unanswered research questions

Protective Effects of Lactobacillus Strains Against Oxidative Stress and Immune Suppression in Mice Receiving Aflatoxin-Contaminated Diet

Mycotoxins like aflatoxins pose a significant threat to the health of both people and animals because of their deadly effects. This study aimed to investigate the potential of Lactobacillus strains in reducing the toxicity caused by aflatoxins in mice receiving a diet contaminated with aflatoxins. The mice were split up into various treatment groups, including a control group, an aflatoxin-treated group, and groups treated with the aflatoxin-contaminated diet along with Lactobacillus strains. Various parameters, including liver enzymes, blood parameters, malondialdehyde (MDA) levels, morphometric analysis of ileum, and gene expression, were analyzed to assess the effectiveness of the Lactobacillus strains in mitigating aflatoxins toxicity. Results showed that mice in the aflatoxin-treated group had increased MDA levels, indicating oxidative stress. Alternatively, the Lactobacillus cocktail treatment group showed a decreasing trend in MDA levels, suggesting a reduction in lipid peroxidation. The morphometric analysis of ileum tissue demonstrated that the Lactobacillus-treated group exhibited improved structural integrity compared to the aflatoxin-treated group. Additionally, gene expression analysis revealed that the Lactobacillus treatment attenuated the downregulation of SOD gene expression and mitigated the upregulation of iNOS gene expression induced by aflatoxins. These findings suggest that Lactobacillus strains have the potential to reduce aflatoxin-induced toxicity by alleviating oxidative stress, preserving intestinal tissue integrity, and modulating gene expression associated with antioxidant defense and inflammation. This study provides evidence for the beneficial effects of Lactobacillus strains in reducing aflatoxin toxicity in mice. The findings obtained may contribute to the development of preventive or therapeutic strategies against mycotoxin-induced toxicity.

Co-contamination and interactions of multiple mycotoxins and heavy metals in rice, maize, soybeans, and wheat flour marketed in Shanghai City

Mycotoxins and heavy metals extensively contaminate grains and grain products, posing severe health risks. This work implements validated ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and inductively coupled plasma mass spectrometry (ICP-MS) methods to quantify the concentration of 12 mycotoxins and five heavy metals in rice, maize, soybeans, and wheat flour samples marketed in Shanghai. The mixed contamination characteristics were analyzed using correlation cluster analysis and co-contamination index, and the probabilities of all cross combinations of contaminations were analyzed using a self-designed JAVA language program. The results showed that grains and grain products were frequently contaminated with both mycotoxins and heavy metals, mostly with deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), 15-acetyl-deoxynivalenol (15-ADON), ochratoxin A (OTA), aflatoxins, fumonisin B1 (FB1), fumonisin B2 (FB2), fumonisin B3 (FB3), arsenic (As), chromium (Cr) and cadmium (Cd). All the samples (100 %) were contaminated with two or more contaminants, and 77.3 % of the samples were co-contaminated with more than four contaminants. In cereals and cereal products, the following combinations were closely associated: (FB3 +3-ADON), (FB1 +As), (FB1 +FB2), (DON+FB1), (DON+Cd), (As+Cd), (DON+Cd+As), (FB1 +FB2 +As), and (DON+3-ADON+15-ADON). The results indicated that mycotoxins and heavy metals frequently co-occurred in Shanghai grains and grain products, and they provided primary data for safety assessments, early warnings, and regulatory measures on these contaminants to protect public health.

New insight into mycotoxins and bacterial toxins: Toxicity assessment, molecular mechanism and food safety (preface to the special issue of food and chemical toxicology on the outcomes of Myco & bacterial toxin)

The special issue "New Insight into Mycotoxins and Bacterial Toxins: Toxicity Assessment, Molecular Mechanism and Food Safety" in Food and Chemical Toxicology contains 19 articles on current hot topics in mycotoxins and bacterial toxins. Dietary exposure to mycotoxins and risk assessments are reported in this issue. Molecular mechanisms of multiple mycotoxins and emerging mechanisms of toxicity are especially concerned by researchers. Moreover, mycotoxin-detoxifying substances and antimicrobial agents are also fully investigated in the context. This special issue will help to further understand the mycotoxins and bacterial toxins, casting new light for the control of food safety.

Evaluating the human neurotoxicity and toxicological interactions impact of co-occurring regulated and emerging mycotoxins

Mycotoxins can inflict harmful effects on diverse organs, and mounting evidence indicates their potential involvement in human neurodegenerative diseases. Given the common occurrence of these toxins in food, there is an increasing demand for a comprehensive assessment of their combined toxicity to enhance our understanding of their potential hazards. This research investigates mycotoxin exposure from widely consumed cereal-based products, including enniatin B (ENNB), sterigmatocystin (STG), aflatoxin B1 (AFB1), cyclopiazonic acid (CPZ), citrinin (CIT), and ochratoxin A (OTA). Employing the median-effect equation based on Chou and Talalay's mass-action law, we assessed their cytotoxicity in human SH-SY5Y neuronal cells. Notably, ENNB displayed the highest neurotoxicity (IC50 = 3.72 µM), followed by OTA (9.10 µM) and STG (9.99 µM). The combination of OTA + STG exhibited the highest toxicity (IC50 = 3.77 µM), while CPZ + CIT showed the least detrimental effect. Approximately 70 % of tested binary combinations displayed synergistic or additive effects, except for ENNB + STG, ENNB + AFB1, and CPZ + CIT, which showed antagonistic interactions. Intriguingly, the senary combination displayed moderate antagonism at the lowest exposure and moderate synergism at higher doses. OTA exhibited predominantly synergistic interactions, comprising approximately 90 %, a noteworthy finding considering its prevalence in food. Conversely, ENNB interactions tended to be antagonistic. The most remarkable synergy occurred in the STG and CIT combination, enabling a 50-fold reduction in CIT dosage for an equivalent toxic effect. These findings highlight the biological relevance of robust synergistic interactions, emphasizing the need to assess human exposure hazards accurately, particularly considering frequent mycotoxin co-occurrence in environmental and food settings.