The Co-Occurrence of T-2 Toxin, Deoxynivalenol, and Fumonisin B1 Activated the Glutathione Redox System in the EU-Limiting Doses in Laying Hens

Fumonisins alone or mixed with other fusariotoxins increase the C22-24:C16 sphingolipid ratios in chicken livers, while deoxynivalenol and zearalenone have no effect

Poultry feed is often contaminated with fumonisins, deoxynivalenol, and zearalenone, which can result in oxidative damage, inflammation and change in lipid metabolism. Although sphingolipids play key roles in cells, only the effects of fumonisins on the sphingolipidome are well-documented. In chickens, fumonisins have been shown to increase the sphinganine to sphingosine ratio and the C22-24:C16 sphingolipid ratio, which has been proposed as a new biomarker of toxicity. In this study, we used UHPLC-MSMS targeted analysis to measure the effect of fusariotoxins on sphingolipids in the livers of chickens fed with diets containing fusariotoxins administered individually and in combination, at the maximum levels recommended by the European Commission. Chickens were exposed from hatching until they reached 35 days of age. This study revealed for the first time that fumonisins, deoxynivalenol, and zearalenone alone and in combination have numerous effects on the sphingolipidome in chicken livers. A 30-50 % decrease in ceramide, dihydroceramide, sphingomyelin, dihydrosphingomyelin, monohexosylceramide and lactosylceramide measured at the class level was observed when fusariotoxins were administered alone, whereas a 30-100 % increase in dihydroceramide, sphingomyelin, dihydrosphingomyelin, and monohexosylceramide was observed when the fusariotoxins were administered in combination. For these different variables, strong significant interactions were observed between fumonisins and zearalenone and between fumonisins and deoxynivalenol, whereas interactions between deoxynivalenol and zearalenone were less frequent and less significant. Interestingly, an increase in the C22-24:C16 ratio of ceramides, sphingomyelins, and monohexosylceramides was observed in chickens fed the diets containing fumonisins only, and this increase was close when the toxin was administered alone or in combination with deoxynivalenol and zearalenone. This effect mainly corresponded to a decrease in sphingolipids with a fatty acid chain length of 16 carbons, whereas C22-24 sphingolipids were unaffected or increased. In conclusion the C22-24:C16 ratio emerged as a specific biomarker, with variations dependent only on the presence of fumonisins.

The Effect of Combined Exposure of Fusarium Mycotoxins on Lipid Peroxidation, Antioxidant Defense, Fatty Acid Profile, and Histopathology in Laying Hens' Liver

Fumonisin B1, T-2 toxin, and deoxynivalenol are frequently detected in feed materials. The mycotoxins induce free radical formation and, thereby, lipid peroxidation. The effects of mycotoxin exposure at the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON = 3AcDON/15-AScDON: 5 mg/kg; fumonisin B1: 20 mg/kg) and double dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg, and FB1: 40 mg/kg feed) were investigated during short-term (3 days) per os exposure in the liver of laying hens. On day 1 higher while on day 3 lower MDA concentrations were found in the low-dose group compared to the control. Fatty acid composition also changed: the proportion of monounsaturated fatty acids increased (p < 0.05) and the proportion of polyunsaturated fatty acids decreased by day 3. These alterations resulted in a decrease in the index of unsaturation and average fatty acid chain length. Histopathological alterations suggested that the incidence and severity of liver lesions were higher in the mycotoxin-treated laying hens, and the symptoms correlated with the fatty acid profile of total phospholipids. Overall, the findings revealed that mycotoxin exposure, even at the EU-recommended limits, induced lipid peroxidation in the liver, which led to changes in fatty acid composition, matched with tissue damage.

Meta-Analysis of the Effects of Yeast Cell Wall Extract Supple-Mentation during Mycotoxin Challenges on the Performance of Laying Hens

A random-effects meta-analysis was conducted to investigate the effect of mycotoxins (MT) without or with the inclusion of yeast cell wall extract (YCWE, Mycosorb®, Alltech, Inc., Nicholasville, KY, USA) on laying hen performance. A total of 25 trials were collected from a literature search, and data were extracted from 8 of these that met inclusion criteria, for a total of 12 treatments and 1774 birds. Laying hens fed MT had lower (p < 0.05) body weight (BW) by -50 g, egg production by -6.3 percentage points, and egg weight by -1.95 g than control fed hens (CTRL). Inclusion of YCWE during the mycotoxin challenges (YCWE + MT) resulted in numerically greater (p = 0.441) BW by 12.5 g, while egg production and egg weight were significantly (p < 0.0001) higher by 4.2 percentage points and 1.37 g, respectively. Furthermore, economic assessment calculations indicated that YCWE may not only support hen performance but also resulted in a positive return on investment. In conclusion, mycotoxins can play a role in negatively impacting laying hen performance and profitability. Inclusion of YCWE in feed with mycotoxin challenges provided benefits to egg production and egg weight and may support profitability. As such, the inclusion of YCWE could play an important role in minimizing mycotoxin effects and in turn aid farm efficiency and profitability.

Pathological consequences, metabolism and toxic effects of trichothecene T-2 toxin in poultry

Contamination of feed with mycotoxins has become a severe issue worldwide. Among the most prevalent trichothecene mycotoxins, T-2 toxin is of particular importance for livestock production, including poultry posing a significant threat to animal health and productivity. This review article aims to comprehensively analyze the pathological consequences, metabolism, and toxic effects of T-2 toxin in poultry. Trichothecene mycotoxins, primarily produced by Fusarium species, are notorious for their potent toxicity. T-2 toxin exhibits a broad spectrum of negative effects on poultry species, leading to substantial economic losses as well as concerns about animal welfare and food safety in modern agriculture. T-2 toxin exposure easily results in negative pathological consequences in the gastrointestinal tract, as well as in parenchymal tissues like the liver (as the key organ for its metabolism), kidneys, or reproductive organs. In addition, it also intensely damages immune system-related tissues such as the spleen, the bursa of Fabricius, or the thymus causing immunosuppression and increasing the susceptibility of the animals to infectious diseases, as well as making immunization programs less effective. The toxin also damages cellular processes on the transcriptional and translational levels and induces apoptosis through the activation of numerous cellular signaling cascades. Furthermore, according to recent studies, besides the direct effects on the abovementioned processes, T-2 toxin induces the production of reactive molecules and free radicals resulting in oxidative distress and concomitantly occurring cellular damage. In conclusion, this review article provides a complex and detailed overview of the metabolism, pathological consequences, mechanism of action as well as the immunomodulatory and oxidative stress-related effects of T-2 toxin. Understanding these effects in poultry is crucial for developing strategies to mitigate the impact of the T-2 toxin on avian health and food safety in the future.

Multi-Fusarium mycotoxin exposure activates Nrf2 and Ahr pathway in the liver of laying hens

This study investigates gene expression changes in laying hens exposed to trichothecene mycotoxins, known to induce oxidative stress and affect xenobiotic transformation and antioxidants. A 3-day feeding trial tested low and high doses of T-2/HT-2 toxin, DON/3-AcDON/15-AcDON, and FB1 in hen feed. Results showed increased expression of AHR, AHRR, HSP90, and CYP1A2 genes on days 2 and 3, suggesting a response to mycotoxin exposure. High doses down-regulated CYP1A2, AHR, and AHRR on day 1. KEAP1 expression decreased on day 1 but increased dose-dependently on days 2 and 3. NRF2 was up-regulated by low and down-regulated by high doses on day 1, then increased on days 2 and 3. Antioxidant-related genes (GPX3, GPX4, GSS, GSR) showed dose-dependent responses. Low doses up-regulated GPX3 and GPX4 throughout, while high doses up-regulated GPX3 on days 2 and 3 and GPX4 on day 3. GSS was up-regulated on day 3. Results indicate that toxic metabolites formed by phase I biotransformation rapidly induce ROS formation at low doses through the AHR/Hsp90/CYP1A2 pathway at the gene expression level, but at high levels, ROS-induced oxidative stress manifests later. Study showed simultaneous activation of redox-sensitive pathways: aryl hydrocarbon receptor (Ahr) and nuclear factor erythroid-derived 2-like 2 (Nrf2) by multi-mycotoxin exposure.

Chronic oral exposure to low-concentration fumonisin B2 significantly exacerbates the inflammatory responses of allergies in mice via inhibition of IL-10 release by regulatory T cells in gut-associated lymphoid tissue

Contamination with fumonisins produced by Fusarium spp. is rapidly growing in both developing and developed countries. The purpose of this study was to determine whether oral exposure to fumonisin contributed to the development of allergic diseases. We initially examined the immunotoxic potential of short-term, oral administration of fumonisin B1 (FB1, 1 mg/kg) and fumonisin B2 (FB2, 1 mg/kg), both naturally occurring fumonisins, using a BALB/c mouse model of allergic contact dermatitis and Dermatophagoides farina-induced asthma. Using an NC/nga mouse model of atopic dermatitis (AD), we evaluated the adverse effects of subchronic oral exposure to low concentrations of FB2 (2 or 200 μg/kg). Finally, we explored the influence of FB2 on regulatory T cell proliferation and function in mesenteric lymph nodes after 1-week oral exposure to FB2 in BALB/c mice. Oral exposure to FB2 markedly exacerbated the symptoms of allergy, including skin thickness, histological evaluation, immunocyte proliferation, and proinflammatory cytokine production, although no change was observed following exposure to FB1. Furthermore, oral exposure to low concentrations of FB2 considerably exacerbated the AD scores, skin thickness, transepidermal water loss, histological features, and proinflammatory cytokine production. The aggravated allergic symptoms induced by oral exposure to FB2 could be attributed to the direct inhibition of IL-10 production by regulatory T cells in mesenteric lymph nodes. Our findings indicate that the recommended maximum fumonisin level should be reconsidered based on the potential for allergy development.

Genetic assessment of the effect of red yeast (Sporidiobolus pararoseus) as a feed additive on mycotoxin toxicity in laying hens

Toxic fungal species produce hazardous substances known as mycotoxins. Consumption of mycotoxin contaminated feed and food causes a variety of dangerous diseases and can even lead to death of animals and humans, raising global concerns for adverse health effects. To date, several strategies have been developed to counteract with mycotoxin contamination. Red yeast as a novel biological dietary agent is a promising strategy to eliminate mycotoxicity in living organisms. Poultry are most susceptible animals to mycotoxin contamination, as they are fed a mixture of grains and are at higher risk of co-exposure to multiple toxic fungal substances. Therefore, this study investigated the genetic mechanism underlying long-term feeding with red yeast supplementation in interaction with multiple mycotoxins using transcriptome profiling (RNA_Seq) in the liver of laying hens. The results showed a high number of significantly differentially expressed genes in liver of chicken fed with a diet contaminated with mycotoxins, whereas the number of Significantly expressed genes was considerably reduced when the diet was supplemented with red yeast. The expression of genes involved in the phase I (CYP1A1, CYP1A2) and phase II (GSTA2, GSTA3, MGST1) detoxification process was downregulated in animals fed with mycotoxins contaminated diet, indicating suppression of the detoxification mechanisms. However, genes involved in antioxidant defense (GSTO1), apoptosis process (DUSP8), and tumor suppressor (KIAA1324, FBXO47, NME6) were upregulated in mycotoxins-exposed animals, suggesting activation of the antioxidant defense in response to mycotoxicity. Similarly, none of the detoxification genes were upregulated in hens fed with red yeast supplemented diet. However, neither genes involved in antioxidant defense nor tumor suppressor genes were expressed in the animals exposed to the red yeast supplemented feed, suggesting decreases the adsorption of biologically active mycotoxins in the liver of laying hens. We conclude that red yeast can act as a mycotoxin binder to decrease the adsorption of mycotoxins in the liver of laying hens and can be used as an effective strategy in the poultry feed industry to eliminate the adverse effects of mycotoxins for animals and increase food safety for human consumers.