Alimentary Risk of Mycotoxins for Humans and Animals.

Mycotoxins can be found in many foods consumed by humans and animals. These substances are secondary metabolites of some fungi species and are resistant to technological processes (cooking, frying, baking, distillation, fermentation). They most often contaminate products of animal (beef, pork, poultry, lamb, fish, game meat, milk) and plant origin (cereals, processed cereals, vegetables, nuts). It is estimated that about 25% of the world's harvest may be contaminated with mycotoxins. These substances damage crops and may cause mycotoxicosis. Many mycotoxins can be present in food, together with mold fungi, increasing the exposure of humans and animals to them. In this review we characterized the health risks caused by mycotoxins found in food, pet food and feed. The most important groups of mycotoxins are presented in terms of their toxicity and occurrence.

Failure of diplodiatoxin to induce diplodiosis in juvenile goats.

Diplodiosis is an important neuromycotoxicosis of ruminants in South Africa when grazing on harvested maize fields in winter. It is believed to be caused by mycotoxin(s) synthesised by Stenocarpella (Diplodia) maydis. Although several metabolites have been isolated from S. maydis culture material, none of these have been administered to ruminants to reproduce the disease. The objectives of this study were to isolate diplodiatoxin and to administer it to juvenile goats. Diplodiatoxin, considered as a major metabolite, was purified from S. maydis-infected maize cultures (Coligny 2007 isolate). Following intravenous administration of 2 mg and 4 mg diplodiatoxin/kg body weight for five consecutive days to two juvenile goats, no clinical signs reminiscent of diplodiosis were observed. Based on previous experimental results and if diplodiatoxin was the causative compound, the dosage regimen employed was seemingly appropriate to induce diplodiosis. In addition, intraruminal administration of 2 mg/kg diplodiatoxin to one goat for three consecutive days also did not induce clinical signs. It appears as if diplodiatoxin alone is not the causative compound. Other metabolites and/or mixtures of diplodiatoxin and other mycotoxins, when available in sufficient quantities, should also be evaluated.

Hemoadsorption Improves Survival of Rats Exposed to an Acutely Lethal Dose of Aflatoxin B1.

Mycotoxins, such as aflatoxin B1 (AFB1), pose a serious threat as biological weapons due to their high toxicity, environmental stability, easy accessibility and lack of effective therapeutics. This study investigated if blood purification therapy with CytoSorb (CS) porous polymer beads could improve survival after a lethal aflatoxin dose (LD90). The effective treatment window and potential therapeutic mechanisms were also investigated. Sprague Dawley rats received a lethal dose of AFB1 (0.5-1.0 mg/kg) intravenously and hemoperfusion with a CS or Control device was initiated immediately, or after 30, 90, or 240-minute delays and conducted for 4 hours. The CS device removes AFB1 from circulation and significantly improves survival when initiated within 90 minutes of toxin administration. Treated subjects exhibited improved liver morphology and health scores. Changes in the levels of cytokines, leukocytes and platelets indicate a moderately-severe inflammatory response to acute toxin exposure. Quantitative proteomic analysis showed significant changes in the level of a broad spectrum of plasma proteins including serine protease/endopeptidase inhibitors, coagulation factors, complement proteins, carbonic anhydrases, and redox enzymes that ostensibly contribute to the therapeutic effect. Together, these results suggest that hemoadsorption with CS could be a viable countermeasure against acute mycotoxin exposure.

Retrospective and Prospective Look at Aflatoxin Research and Development from a Practical Standpoint.

Among the array of structurally and toxicologically diverse mycotoxins, aflatoxins have attracted the most interest of scientific research due to their high toxicity and incidence in foods and feeds. Despite the undeniable progress made in various aspects related to aflatoxins, the ultimate goal consisting of reducing the associated public health risks worldwide is far from being reached due to multiplicity of social, political, economic, geographic, climatic, and development factors. However, a reasonable degree of health protection is attained in industrialized countries owing to their scientific, administrative, and financial capacities allowing them to use high-tech agricultural management systems. Less fortunate situations exist in equatorial and sub-equatorial developing countries mainly practicing traditional agriculture managed by smallholders for subsistence, and where the climate is suitable for mould growth and aflatoxin production. This situation worsens due to climatic change producing conditions increasingly suitable for aflatoxigenic mould growth and toxin production. Accordingly, it is difficult to harmonize the regulatory standards of aflatoxins worldwide, which prevents agri-foods of developing countries from accessing the markets of industrialized countries. To tackle the multi-faceted aflatoxin problem, actions should be taken collectively by the international community involving scientific research, technological and social development, environment protection, awareness promotion, etc. International cooperation should foster technology transfer and exchange of pertinent technical information. This review presents the main historical discoveries leading to our present knowledge on aflatoxins and the challenges that should be addressed presently and in the future at various levels to ensure higher health protection for everybody. In short, it aims to elucidate where we come from and where we should go in terms of aflatoxin research/development.

Acute hepatic necrosis and death in a subadult southern white rhinoceros (Ceratotherium simum) associated with exposure to sterigmatocystin in forage contaminated with Aspergillus nidulans.

A young male southern white rhinoceros (Ceratotherium simum), which was resident in a zoo as part of a multi-rhinoceros group, died suddenly. Necropsy and histopathological findings supported a diagnosis of death from acute hepatic necrosis. The microscopic distribution of liver lesions was suggestive of hepatotoxicosis. Further investigation revealed potential exposure to a mycotoxin, sterigmatocystin, present in spoiled lucerne hay contaminated with Aspergillus nidulans. It was concluded that mycotoxicosis was the likely cause of the hepatic necrosis and death in this animal.

Introducing Mushroom Fruiting Patterns from the Swiss National Poisons Information Centre.

Changes in the ecology of macrofungi are poorly understood, not only because much of their life cycle is hidden belowground, but also because experiments often miss real-world complexity and most fruitbody inventories are limited in space and time. The National Poisons Information Centre 'Tox Info Suisse' provides countrywide 24hours/7days medical advice in case of poisonings since 1966. Here, we introduce a total of 12,126 mushroom-related phone calls that were received by Tox Info Suisse between 1966 and 2014. This indirect source of mycological information is dominated by the families of Boletaceae (11%), Agaricaceae (10%) and Amanitaceae (8%), which account for ~30% of all cases. Mushroom fruiting patterns revealed by the Poisons Centre inventory statistically resemble changes in fungal phenology, productivity and diversity as reflected by the Swiss National Data Centre 'SwissFungi'. Although the newly developed Tox Info Suisse dataset provides an innovative basis for timely environmental research, caution is advised when interpreting some of the observed long-term changes and autumnal extremes. Uncertainty of the new record relates to possible data incompleteness, imprecise species description and/or identification, as well as the inclusion of cultivated and non-indigenous mushrooms. Nevertheless, we hope that the Tox Info Suisse inventory will stimulate and enable a variety of ecological-oriented follow-up studies.

Aflatoxin B1 and total fumonisin contamination and their producing fungi in fresh and stored sorghum grain in East Hararghe, Ethiopia.

Natural contamination of sorghum grains by aflatoxin B1 and total fumonisin and their producing toxigenic fungi has been studied. A total of 90 sorghum grain samples were collected from small-scale farmers' threshing floors and 5-6 months later from underground pits during 2013 harvest from three districts of East Hararghe, Ethiopia. Mycotoxin analysis was done using enzyme-linked immunosorbent assay (ELISA). The limits of detection were in the range 0.01-0.03 µg kg-1. The results revealed that all sorghum grain samples were contaminated with both Aspergillus and Fusarium species. Aflatoxin B1 was detected at levels ranging from

Environment contamination by mycotoxins and their occurrence in food and feed: Physiological aspects and economical approach.

The contamination of food and feed by mycotoxins as toxic metabolites of fungi is a risk not only for consumers resulting in various embarrassment regarding health status and well-being, but also for producers, companies and export market on the ground of economic losses and ruined stability of economic trade. As it is given in historical evidence, the contamination of food by mycotoxins is a topic as old as a history of mankind, finding some evidence even in the ancient books and records. Nowadays, the mycotoxins are used in modern biotechnological laboratories and are considered an agent for targeting the specific cells (e.g., defected cells to eliminate them). However, this promising procedure is only the beginning. More concern is focused on mycotoxins as abiotic hazard agents. The dealing with them, systematic monitoring, and development of techniques for their elimination from agricultural commodities are worldwide issues concerning all countries. They can be found alone or in co-occurrence with other mycotoxins. Thus, this review aims to provide widened information regarding mycotoxins contamination in environment with the consequences on health of animals and humans. The inevitability for more data that correctly determine the risk points linked to mycotoxins occurrence and their specific reactions in the environment is demonstrated. This review includes various symptoms in animals and humans that result from mycotoxin exposure. For better understanding of mycotoxin's impact on animals, the sensitivities of various animal species to various mycotoxins are listed. Strategies for elimination and preventing the risks of mycotoxins contamination as well as economical approach are discussed. To complete the topic, some data from past as historical evidences are presented.

Protective effect of curcumin against experimentally induced aflatoxicosis on the renal cortex of adult male albino rats: a histological and immunohisochemical study.

BACKGROUND: Aflatoxin contamination of foods is a worldwide problem. Chronic aflatoxin exposure is associated with kidney damage. Curcumin is a herbal agent, used in medicine with a wide range of beneficial therapeutic effects. OBJECTIVE: to evaluate the effect of curcumin against experimentally induced aflatoxicosis on the renal cortex of adult male albino rats. MATERIALS AND METHODS: Forty adult male rats were included and they were divided equally into 4 groups (10 rats each): Group I (control group), group II (Curcumin group): The rats received curcumin (200 mg/kg b.w.) orally by gastric tube for 5 days/week, group III (Aflatoxin B1 group): The rats received aflatoxin B1 (250 µg/kg b.w./day) orally by gastric tube 5 days/week for 4 weeks, group IV (Aflatoxin B1 and Curcumin group): The rats received aflatoxin and curcumin orally by gastric tube 5 days/week for 4 weeks. Kidney specimens were prepared and sections were stained with hematoxylin and eosin, Masson's trichrome, Periodic acid Schiff, immunohistochemical detection of desmin and Bcl2. RESULTS: The tubules of group III showed degenerative and necrotic changes with disruption of basal lamina. There was a significant decrease Bcl2 expression in the tubules, but the glomeruli showed an enlargement with dilation of their capillaries lumina in some areas, while the other areas showed glomerular atrophy with obliteration of their capillaries lumina. There was a significant increase in desmin expression in the glomerular cells. The interstitium showed hemorrhage and cellular infiltration. Group IV showed improvement of the histological and immunohistochemical changes described before. CONCLUSION: Aflatoxin B1 has deleterious effects of on the histological structure of the rat's renal cortex and curcumin minimized these effects as it has antioxidant, anti-inflammatory and antiapoptotic activities. We advise eating nutritious diets that contain sufficient amounts of curcumin and regulation must implement to avoid the presence of aflatoxins in high concentrations in human food.

Characterization of cell death caused by diplodiatoxin and dipmatol, toxic metabolites of Stenocarpella maydis.

Diplodiosis, a neuromycotoxicosis of cattle and sheep grazing on mouldy cobs infected by Stenocarpella maydis, is considered the last major veterinary mycotoxicosis for which the causative mycotoxin is still unknown. The current study was aimed at characterizing the cell death observed in mouse neuroblastoma (Neuro-2a), Chinese hamster ovary (CHO-K1) and Madin-Darby bovine kidney (MDBK) cell lines exposed to the S. maydis metabolites (i.e. diplodiatoxin and dipmatol) by investigating the roles of necrosis and apoptosis. Necrosis was investigated using the lactate dehydrogenase (LDH) leakage and propidium iodide (PI) flow cytometry assays and apoptosis was evaluated using the caspase-3/7 and Annexin V flow cytometry assays. In addition, transmission electron microscopy (TEM) was used to correlate the cell death pathways observed in this study with their typical morphologies. Both diplodiatoxin and dipmatol (750 µM) induced necrosis and caspase-dependent apoptosis in Neuro-2a, CHO-K1 and MDBK cells. Ultrastructurally, the two mycotoxins induced mitochondrial damage, cytoplasmic vacuolation and nuclear fragmentation in the three cell lines. These findings have laid a foundation for future studies aimed at elucidating in detail the mechanism of action of the S. maydis metabolites.

The effect of experimental fusarium mycotoxicosis on microbiota diversity in porcine ascending colon contents.

The objective of the study was to determine the effect of exposure of pigs to the Fusarium mycotoxins zearalenone (ZEN) and deoxynivalenol (DON), administered together and separately, on the colon microbiota. An experiment was conducted for 42 days on gilts, randomly assigned to four groups and administered either ZEN, DON, ZEN+DON, or a placebo. The number of aerobic mesophilic bacteria, yeasts, molds, anaerobic Clostridium perfringens, fecal streptococci, Enterobacteriaceae, Escherichia coli, and lactic acid bacteria (LAB) were determined in the contents of the ascending colon. The influence of mycotoxins on the functional diversity of the colonic microbiota was assessed using EcoPlate tests (Biolog). Analysis revealed the predominance of LAB in all groups of pigs. Zearalenone, administered separately and together with DON, was found to have an adverse effect on mesophilic aerobic bacteria, but only after long exposure to this mycotoxin. During the six weeks of the experiment, the concentration of C. perfringens, E. coli, and other bacteria in the family Enterobacteriaceae was most considerably reduced in the experimental groups exposed to zearalenone, both separately and together with DON. Mycotoxins also affected the functional biodiversity of microorganisms. Both Shannon's diversity index and the number of catabolized substrates in Biolog plate (the R index) were much higher in the group subjected to mixed mycotoxicosis.

Multitoxin analysis of Aspergillus clavatus-infected feed samples implicated in two outbreaks of neuromycotoxicosis in cattle in South Africa.

Aspergillus clavatus intoxication is a highly fatal neuromycotoxicosis of ruminants, especially cattle. It is caused by the ingestion of infected sprouting grain and sorghum beer residue. Locomotor disturbances, tremors and paralysis are observed. Histologically, degeneration and necrosis of larger neurons in the medulla oblongata, the midbrain, the thalamus and the ventral horns of the spinal cord are observed. Although a range of mycotoxins such as patulin, cytochalasin E and pseurotin A have been isolated, there is limited information on which specific mycotoxin or group of mycotoxins are involved during outbreaks of intoxication in livestock. In the present study, two outbreaks of A. clavatus poisoning in cattle are briefly described. Feed samples were collected for fungal identification, and culture and multitoxin analysis. A range of fungal metabolites were detected, and the estimated concentrations (µg/kg) are provided. Both the sprouting barley and brewer's grain were predominantly infected with A. clavatus and, to a lesser extent, Rhizopus arrhizus. The only common Aspergillus secondary metabolite present in all the samples was pseurotin A. Patulin and cytochalasin E were present in the sprouting barley samples, as well as the A. clavatus isolates cultured on malt extract agar for 2 weeks; however, neither of these mycotoxins could be detected in the brewer's grain sample.

Mycotoxicoses in children.

Mycotoxicoses are acute and chronic poisonings caused by mould toxins called mycotoxins. Although acute mycotoxicoses, caused by high mycotoxin levels in food are rare nowadays, they need to be described in order to inform physicians and other health care workers about their symptoms. Children are more sensitive to mycotoxins because of their lower body mass, higher metabolic rate, and underdeveloped organ functions and detoxication mechanisms. Some mycotoxicoses appear only in children, and some are more pronounced in children than in adults. Acute mycotoxicoses in children are reported poorly, mostly because they occur in the tropical regions with poor healthcare coverage. In developed countries healthcare authorities are more concerned about child exposure to low levels of mycotoxins with immunotoxic, genotoxic or carcinogenic properties.

Nanosilver effects on growth parameters in experimental aflatoxicosis in broiler chickens.

Aflatoxicosis is a cause of economic losses in broiler production. In this study, the effect of one commercial nanocompound, Nanocid (Nano Nasb Pars Co., Iran) was evaluated in reduction of aflatoxin effects on the growth and performance indices in broiler chickens suffering from experimental aflatoxicosis. For this, a total of 300 one-day-old broiler chicks (Ross strain) were randomly divided into 4 groups with 3 replicates of 15 chicks in each separated pen during the 28-day experiment. Treatment groups including group A: chickens fed basal diet, group B: chickens fed 3 ppm productive aflatoxin in basal diet, group C: chickens fed basal diet plus 2500 ppm Nanocid, and group D: chickens fed 3 ppm productive aflatoxin and 2500 ppm Nanocid, in basal diet. Data on body weight, body weight gain (BWG), feed intake, and feed conversion ratio (FCR) were recorded at weekly intervals. Also cumulative data were assessed. Results showed, although supplement of Nanocid to conventional diet had no effect on performance but addition of Nanocid to diet containing 3 ppm aflatoxin increased significantly the cumulative BWG, cumulative feed consumption and decreased FCR in the last 2 weeks of experimental period. The improvement in these performance indices by supplement of Nanocid to diet containing aflatoxin showed the ability of Nanocid to diminish the inhibitory effects of aflatoxin.

Acute and chronic disease associated with naturally occurring T-2 mycotoxicosis in sheep.

A flock of approximately 1,000 sheep were exposed intermittently to food contaminated with T-2 toxin (T-2), a potent type-A trichothecene mycotoxin produced primarily by Fusarium sporotrichioides and Fusarium poae. In the acute stage of the intoxication, affected sheep developed anorexia, decreased water consumption, ruminal atony, soft faeces and apathy. One hundred and ninety of the exposed sheep died. The main gross lesions observed in animals dying during the acute disease were rumenitis and ulcerative abomasitis, depletion of lymphocytes in lymphoid organs, necrosis of the exocrine pancreas, myocarditis and intense oedema of the skin and brain. Sheep developing the chronic stage of disease showed weight loss and reproductive inefficiency and the main pathological features observed in animals dying during this stage were gastrointestinal inflammation, myocardial fibrosis and necrotic and suppurative lesions in the oral cavity. Opportunistic infections (e.g. mycotic mastitis or parasitic pneumonia) were also identified in these animals. Increased serum concentrations of lactate dehydrogenase and creatine kinase were observed, most likely related to heart lesions. T-2 toxins were detected in all samples of the diet of these animals that were analyzed. The changes in the sheep reported here are similar to those described previously in experimental studies. Lesions observed in the present animals suggest an additional cardiotoxic effect of T-2 in sheep.

Mycotoxins and human health.

Mycotoxins have been investigated in relation to a wide range of adverse human health effects, but the evidence for all but a small number of associations is limited. Thus, the full impact on human health of the widespread exposure to mycotoxins remains to be defined. The main exception is for aflatoxins; epidemiological, experimental, and mechanistic studies have contributed to establishing aflatoxins as a cause of human liver cancer, with a particularly elevated risk in people chronically infected with hepatitis B virus. In addition, acute aflatoxicosis after exposure to high dietary toxin levels has been demonstrated. The impairment of child growth by aflatoxin exposure early in life remains an important subject of study. More information is also required on the potential immune effects of aflatoxins, especially in vulnerable populations. For fumonisins, studies indicate a possible role in oesophageal cancer and in neural tube defects, although no definitive conclusions can be drawn at present. For deoxynivalenol and other trichothecenes, exposure has been linked to acute poisoning outbreaks in large numbers of subjects. For ochratoxin A and zearalenone, the human health effects remain undefined. The limited tools available to accurately assess human exposure to mycotoxins and the relative paucity of epidemiological studies need to be addressed if the full extent of the adverse effects of these common dietary contaminants is to be understood and adequate public health measures taken. In this respect, newly established biomarkers of exposure at the individual level are proving valuable in improving exposure assessment in epidemiological studies.

[Tremorgenic syndrome in a cattle herd after feeding silage contaminated with A. clavatus]. / Tremorgenes Syndrom in einem Rinderbestand nach Verfütterung einer mit A. clavatus befallenen Silage.

The clinical signs, pathological and laboratory findings of cattle suffering from a tremorgenic syndrome are described. Animals on a farm with a total of 22 cows, 18 heifers and 9 calves were fed mouldy grass and spent malt-grain silage. Five heifers were affected with muscular tremor, hyperexcitability and hypersensitivity. They were ataxic or in sternal recumbency, while their appetite remained normal. Haematology and blood chemistry in two heifers as well as cerebrospinal fluid from one sick animal were unremarkable. The pathological examination of one animal brought no macroscopic changes to light. Histological examination, however, revealed the degeneration of motor neurones in the midbrain, brain stem and spinal cord. Analysis of a silage sample provided evidence of the presence of Aspergillus clavatus, a mould capable of producing neurotoxic tremorgenic mycotoxins. Epidemiology, clinical findings, pathology and microbiological examination suggest that the five cattle were suffering from neuromycotoxicosis.

Mycotoxic nephropathy in Bulgarian pigs and chickens: complex aetiology and similarity to Balkan endemic nephropathy.

Spontaneous nephropathy in Bulgaria, which is observed frequently during meat inspection and which differs morphologically from the classical description of mycotoxic porcine/chicken nephropathy as made in Denmark, was found to have a multi-mycotoxic aetiology being mainly provoked by a combined effect of ochratoxin A, penicillic acid and fumonisin B1 in addition to a not-yet-known metabolite. Mean contamination levels of ochratoxin A were consecutively low (188.8 and 376.4 microg kg(-1)) in contrast to high contamination levels of fumonisin B1 (5564.1 and 3254.5 microg kg(-1)) and penicillic acid (838.6 and 904.9 microg kg(-1)) for 2006 and 2007, respectively. Some other mycotoxins with lower importance such as citrinin, penitrem A, etc., may also influence clinicopathological picture of this nephropathy. A heavy contamination with Gibberella fujikuroi var. moniliformis (Fusarium verticillioides) and Penicillium aurantiogriseum complex (mainly Penicillium polonicum) was observed in almost all examined feed samples coming from pig and chick farms with nephropathy problems from Bulgaria. In contrast, low contamination with Aspergillus ochraceus, Penicillium verrucosum and Penicillium citrinum was observed in the same feed samples and these species were isolated as very rare components of the mycobiota.

Effects of Fusarium mycotoxin butenolide on myocardial mitochondria in vitro.

Fusarium mycotoxin toxicosis has been implicated in the etiology of Keshan disease, an endemic mitochondrial cardiomyopathy prevailing in certain areas of China. Butenolide (4-acetamido-4-hydroxy-2-butenoic acid gamma-lactone) is one of the Fusarium mycotoxins which are frequently detected from cereal grains in endemic areas. A recent study indicates that this mycotoxin induces rat cardiotoxicity, but its effect on the myocardial mitochondria remains unclear. The present study is therefore undertaken to explore the toxic effect potential of butenolide on the myocardial mitochondria. Exposure of cultured cardiac myocytes to 50 microg/ml of butenolide provoked dissipation of mitochondrial membrane potential. Incubation of isolated rat myocardial mitochondria with butenolide of 100 microg/ml for 60 min resulted in mitochondrial swelling, indicating the occurrence of mitochondrial permeability transition. Furthermore, marked oxidative damage in myocardial mitochondria was observed after incubation of isolated myocardial mitochondria with butenolide ranging from 0 to 50 microg/ml for 60 min, as manifested by concentration-dependent increases in the production of thiobarbituric acid reactive substances, the indicator of lipid peroxidation. Contrarily, a representative antioxidant glutathione significantly alleviated this oxidative mitochondrial damage induced by butenolide. In conclusion, these observations clearly show that butenolide can induce dysfunction of myocardial mitochondria, and oxidative damage appears to play a crucial role in these deleterious effects. The present study supports the hypothesis that mycotoxin toxicosis is a probable etiological factor of Keshan disease, the mitochondrial cardiomyopathy.