101
|
Abstract
Mycotoxins are toxic secondary metabolites of fungi. Diseases caused by mycotoxins are collectively referred to as mycotoxicosis. Disease is usually initiated after ingestion of feeds containing toxic doses of mycotoxins. Signs and symptoms vary and depend on the animal, the organ system involved, and on the dose and type of mycotoxins ingested. The symptoms can range from acute death, immunosuppression to skin lesions or to signs of hepatotoxicity, nephrotoxicity, neurotoxicity, or genotoxicity. In addition to concerns over adverse effects of mycotoxins on food animals consuming mycotoxin-contaminated feeds, there is also a public health concern over the potential for human beings to consume animal-derived food products such as meat, milk, or eggs, containing residues of those mycotoxins or their metabolites.
Collapse
Affiliation(s)
- K Hollinger
- Division of Epidemiology and Surveillance, United States Food and Drug Administration, Rockville, Maryland, USA
| | | |
Collapse
|
102
|
Abstract
Apoptosis is a highly regulated mechanism of cell death. Although apoptosis has a functional role in normal development and tissue homeostasis, aberrant triggering of the process by toxicants may lead to abnormal function or disease. Low level exposures to toxicants that induce apoptosis in kidney may therefore create a critical disturbance in kidney homeostasis, contributing to renal neoplasia or renal disease. In this report, we review the involvement of apoptosis in normal kidney development and in renal disease and discuss some of the toxicants and molecular factors involved in regulation of the process in renal cells.
Collapse
Affiliation(s)
- M A Davis
- Department of Pathology, School of Medicine, University of Maryland, Baltimore 21201, USA.
| | | |
Collapse
|
103
|
Voss KA, Plattner RD, Riley RT, Meredith FI, Norred WP. In vivo effects of fumonisin B1-producing and fumonisin B1-nonproducing Fusarium moniliforme isolates are similar: fumonisins B2 and B3 cause hepato- and nephrotoxicity in rats. Mycopathologia 1998; 141:45-58. [PMID: 9725030 DOI: 10.1023/a:1006810916344] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Fumonisins are mycotoxins produced by Fusarium moniliforme, F. proliferatum, and related Fusarium species found on corn. They occur naturally in corn-based feeds and foods and are suspected human esophageal carcinogens. Fumonisin B1 (FB1), the most common homologue, causes the animal diseases associated with F. moniliforme. Hepato- and nephrotoxicities, disrupted sphingolipid metabolism, and liver cancer have been found in rats fed FB1. To determine the in vivo effects of diets containing fumonisins B2 (FB2) or B3 or (FB3), male rats were fed culture materials (CM) of FB1 non-producing F. moniliforme isolates to provide low (4.6-6.7 ppm), mid (32-49 ppm) or high (219-295 ppm) dietary levels of either FB2 (FB2CM) or FB3 (FB3CM). Other groups were fed culture material of an FB1 producing isolate (FB1CM) providing 6.9, 53 or 303 ppm total fumonisins (FB1: FB2: FB3 = 1.0: 0.38: 0.15) and a tenth group was fed a control diet having no detectable fumonisins. One-half (n = 5/group) the animals were killed after three weeks, at which time the toxicological and histopathological effects of the three culture materials were similar, mimicked the effects of FB1, and included decreased body weight gains, serum chemical indicators of hepatotoxicity, decreased kidney weights, and apoptosis of hepatocytes and kidney tubular epithelium. FB1CM, FB2CM, and FB3CM affected sphingolipids, causing increased sphinganine to sphingosine ratios (Sa/So) in both liver and kidneys. The remaining animals (n = 5/group0 were fed a control diet for three additional weeks. All body weight and tissue specific effects, including increased Sa/So, induced by the FB2Cm, FB3CM and low level FB1CM diets were absent following the recovery period. Except for mild biliary lesions found in the high dose of FB1CM group and a few apoptotic hepatocytes present in one mid- and two high-dose FB1CM rats, no evidence of toxicity remained in these groups, following the recovery period.
Collapse
Affiliation(s)
- K A Voss
- Toxicology and Mycotoxin Research Unit, USDA, Richard B. Russell Agricultural Research Center, Athens, Georgia 30604-5677, USA
| | | | | | | | | |
Collapse
|
104
|
Abstract
The fumonisins are a recently identified group of fungal toxins, occurring worldwide in naturally contaminated maize, which have elicited considerable attention over the past decade due to their association with the animal disease syndromes, equine leukoencephalomalacia and porcine pulmonary oedema, and their reported association with oesophageal cancer in rural areas of Transkei, South Africa and Linxian County, China. This paper reviews the development of sensitive chromatographic analytical methods for the determination of these toxins in a range of mainly maize or maize-based food matrices. Initial attempts at gas chromatographic determination of these toxins were supplanted by the successful development of liquid chromatographic methods based on solid-phase extraction (SPE) of solvent extracts, followed by precolumn derivatisation and HPLC determination using fluorescence detection. The most widely used method involves strong anion-exchange (SAX) SPE and the use of o-phthaldialdehyde as derivatising agent. In contrast, the development of thin-layer chromatographic methods enables large numbers of samples to be screened economically. The recent advances in liquid chromatography-mass spectrometry have resulted in the development of suitable methods for fumonisin analysis without the need of derivatisation.
Collapse
Affiliation(s)
- G S Shephard
- Programme on Mycotoxins and Experimental Carcinogenesis, Medical Research Council, Tygerberg, South Africa
| |
Collapse
|
105
|
de Nijs M, Sizoo EA, Vermunt AE, Notermans SH, van Egmond HP. The occurrence of fumonisin B1 in maize-containing foods in The Netherlands. FOOD ADDITIVES AND CONTAMINANTS 1998; 15:385-8. [PMID: 9764206 DOI: 10.1080/02652039809374656] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Seventy-eight maize-containing foods obtained from retail stores in The Netherlands were analysed for fumonisin B1 contamination. Thirty-six per cent of the samples were contaminated with fumonisin B1 in the range of 8 micrograms kg-1 (limit of detection) to 1430 micrograms/kg-1. Forty-six per cent of the minimally treated maize samples (n = 39; maize for bread production, maize for popcorn, maize flour and polenta) were contaminated with fumonisin B1 in the range of 8-380 micrograms kg-1. Twenty-six per cent of the maize-containing processed foods (n = 39; tostada, canned maize, maize starch, maize bread, popped maize, flour mixes, maize chips and cornflakes) were contaminated with fumonisin B1 in the range of 8-1430 micrograms/kg-1. This survey shows that maize-containing foods in The Netherlands frequently can be contaminated with fumonisin B1.
Collapse
Affiliation(s)
- M de Nijs
- Wageningen Agricultural University, Department of Food Science, The Netherlands
| | | | | | | | | |
Collapse
|
106
|
de Nijs M, Sizoo EA, Rombouts FM, Notermans SH, van Egmond HP. Fumonisin B1 in maize for food production imported in The Netherlands. FOOD ADDITIVES AND CONTAMINANTS 1998; 15:389-92. [PMID: 9764207 DOI: 10.1080/02652039809374657] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Sixty-two samples of maize imported in The Netherlands and intended for human consumption were screened for the presence and concentration of fumonisin B1. Sixty-one of those samples contained fumonisin B1 with concentrations ranging from 30 to 3350 micrograms kg-1, 11 maize samples contained > 1000 micrograms kg-1. The average fumonisin B1 concentration was 640 micrograms kg-1 for the positive samples and 620 micrograms kg-1 for all samples. Medians were 600 micrograms kg-1 and 550 micrograms kg-1 for positive and all samples, respectively. The results obtained were comparable to results from other studies in maize from various countries.
Collapse
Affiliation(s)
- M de Nijs
- Wageningen Agricultural University, Department of Food Science, The Netherlands
| | | | | | | | | |
Collapse
|
107
|
Fazekas B, Bajmócy E, Glávits R, Fenyvesi A, Tanyi J. Fumonisin B1 contamination of maize and experimental acute fumonisin toxicosis in pigs. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1998; 45:171-81. [PMID: 9588111 DOI: 10.1111/j.1439-0450.1998.tb00780.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The fumonisin B1 content of 69 visibly mouldy and 23 mould-free maize samples grown in Hungary in 1993-1995 was determined by high-performance liquid chromatography (HPLC). Fumonisin B1 was found to occur in 70-73% of the mouldy samples. The mycotoxin level increased from year to year: the highest fumonisin B1 concentration was 75.1 mg/kg. The samples that were mould-free on visual inspection showed a much lower prevalence of fumonisin B1 contamination (30%) and contained fumonisin B1 in markedly lower concentrations (average, 1.52 mg/kg; maximum concentration, 5.1 mg/kg). Using the Fusarium moniliforme strain designated 14/A, isolated from the sample that had the highest mycotoxin concentrations, fumonisin B1 toxin was produced on maize by an internationally accepted procedure. Subsequently, two weaned piglets were fed a diet containing 330 mg fumonisin B1 per kg of feed. The experimental animals developed hydrothorax and pulmonary oedema, and died in 5-6 days. The clinical symptoms and pathological lesions were consistent with those of porcine pulmonary oedema (PPE) diagnosed in the USA in 1989-1990, as well as with those of a disease entity that had already been described in Hungary in the 1950s as the so-called fattening or unique pulmonary oedema of pigs but considered to be of unknown aetiology. The results of the feeding trial confirm that this pig disease, which has occurred in Hungary for a long time, is caused by the mycotoxin fumonisin B1.
Collapse
Affiliation(s)
- B Fazekas
- Veterinary Institute of Debrecen, Hungary
| | | | | | | | | |
Collapse
|
108
|
Voss KA, Riley RT, Bacon CW, Meredith FI, Norred WP. Toxicity and sphinganine levels are correlated in rats fed fumonisin B(1) (FB(1)) or hydrolyzed FB(1). ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 1998; 5:101-104. [PMID: 21781855 DOI: 10.1016/s1382-6689(97)10009-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/1997] [Revised: 09/01/1997] [Accepted: 09/03/1997] [Indexed: 05/31/2023]
Abstract
Nixtamalization of Fusarium moniliforme culture material reduced, but did not eliminate, its toxicity to rats. Liver and kidney sphinganine concentration and sphinganine to sphingosine ratio of the animals fed diets containing water extracted (8 ppm fumonisin B(1) (FB(1))), nixtamalized (58 ppm hydrolyzed FB(1)), or unprocessed culture material (71 ppm FB(1)) were increased compared to those fed a diet lacking detectable fumonisins. Increases were generally correlated with the severity of hepatic and renal lesions and were highly correlated (P<0.0001) with body weight effects and serum chemical indications of hepatotoxicity. The findings are further evidence that inhibition of the enzyme ceramide synthase may be a key event in fumonisin toxigenesis.
Collapse
Affiliation(s)
- K A Voss
- Toxicology and Mycotoxin Research Unit, Richard B. Russell Agricultural Research Center, Agricultural Research Service, USDA, P.O. Box 5677, Athens, GA 30604-5677, USA
| | | | | | | | | |
Collapse
|
109
|
Gilchrist DG. Programmed cell death in plant disease: the purpose and promise of cellular suicide. ANNUAL REVIEW OF PHYTOPATHOLOGY 1998; 36:393-414. [PMID: 15012506 DOI: 10.1146/annurev.phyto.36.1.393] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The interaction of pathogens with plants leads to a disruption in cellular homeostasis, often leading to cell death, in both compatible and incompatible relationships. The mechanistic basis of this cellular disruption and consequent death is complex and poorly characterized, but it is established that host responses to pathogens are dependent on gene expression, involve signal transduction, and require energy. Recent data suggest that in animals, a genetically regulated, signal transduction-dependent programmed cell death process, commonly referred to as apoptosis, is conserved over a wide range of phyla. The basic function of apoptosis is to direct the selective elimination of certain cells during development, but it also is a master template that is involved in host responses to many pathogens. Programmed cell death in plants, while widely observed, has not been studied extensively at either the biochemical or genetic level. Current data suggest that activation or suppression of programmed cell death may underlie diseases in plants as it does in animals. This review describes some of the fundamental characteristics of apoptosis in animals and points to a number of connections to programmed cell death in plants that may lead to both a better understanding of disease processes and novel strategies for engineering disease resistance in plants.
Collapse
Affiliation(s)
- D G Gilchrist
- Department of Plant Pathology and the NSF Center for Engineering Plants for Resistance Against Pathogens, University of California, Davis, California 95616, USA.
| |
Collapse
|
110
|
Norred WP, Plattner RD, Dombrink-Kurtzman MA, Meredith FI, Riley RT. Mycotoxin-induced elevation of free sphingoid bases in precision-cut rat liver slices: specificity of the response and structure-activity relationships. Toxicol Appl Pharmacol 1997; 147:63-70. [PMID: 9356308 DOI: 10.1006/taap.1997.8272] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Fumonisin B1 (FB1) is the predominant member of a family of toxic metabolites produced by several species of Fusarium and is commonly found on corn. FB1 is a potent competitive inhibitor of ceramide synthase, which catalyzes the conversion of sphinganine and sphingosine to ceramide. The resultant accumulation of free sphingoid bases and the disruption of sphingolipid metabolism is believed to be the mechanism of toxicity of the fumonisins. The objectives of this study were to determine the relative potency of analogs of FB1 to inhibit ceramide synthase and to determine whether the inhibition is specific to mycotoxins with fumonisin-like structures. Fumonisins B1, B2, B3, B4, C4, and TA toxin (a structurally similar mycotoxin produced by the tomato pathogen, Alternaria alternata f. sp. lycopersici) were approximately equipotent inhibitors. Hydrolyzed fumonisins B1, B2, and B3, which lack the tricarballylic side chains, were only 30-40% as potent as the parent toxins. N-acetylated FB1 (FA1) did not block ceramide synthase, suggesting that FA1 is nontoxic. Inhibition of ceramide synthase by fumonisin analogs did not appear to be related to the lipophilicity of the compounds, as determined by computer estimation of log P values. The ability of relatively high (10 and 100 microm) doses of other mycotoxins that bear no structural similarity to fumonisins, including aflatoxin B1, cyclopiazonic acid, beauvericin, T-2 toxin, sterigmatocystin, luteoskyrin, verrucarin A, scirpentriol, and zearalenone, to block ceramide synthase was also determined. All of the toxins tested were negative in the bioassay with the exception of fumonisins, indicating that disruption of sphingolipid metabolism is a specific cytotoxic response.
Collapse
Affiliation(s)
- W P Norred
- Richard B. Russell Agricultural Research Center, ARS/USDA, Athens, Georgia 30604-5677, USA
| | | | | | | | | |
Collapse
|
111
|
NIJS M, EGMOND H, ROMBOUTS F, NOTERMANS S. IDENTIFICATION OF HAZARDOUS FUSARIUM SECONDARY METABOLITES OCCURRING IN FOOD RAW MATERIALS. J Food Saf 1997. [DOI: 10.1111/j.1745-4565.1997.tb00185.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
112
|
Bondy GS, Suzuki CA, Fernie SM, Armstrong CL, Hierlihy SL, Savard ME, Barker MG. Toxicity of fumonisin B1 to B6C3F1 mice: a 14-day gavage study. Food Chem Toxicol 1997; 35:981-9. [PMID: 9463532 DOI: 10.1016/s0278-6915(97)87267-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Fumonisin B1 (FB1) is a fungal toxin produced by members of the genus Fusarium. Ingestion of FB1 causes species-specific neurotoxic, nephrotoxic, hepatotoxic and pulmonary effects. The clinical, haematological and pathological responses of adult male and female B6C3F1 mice to FB1 were assessed following 14 daily gavage doses ranging from 1 to 75 mg FB1/kg body weight/day. There were no consistent sex-related changes. Although all responses were modest, the most notable effects of FB1 were on the liver, bone marrow, adrenals and kidneys. In the liver, hepatocellular single cell necrosis, mitosis and anisokaryosis were observed, accompanied by elevated serum ALT. In the kidneys, minor histopathological changes were confined to female mice, while mild decreases in ion transport and increases in blood urea nitrogen were seen only in males. Small changes in glutathione levels were observed in the kidneys and livers of male mice. Adrenal cortical cell vacuolation was observed at 15 mg FB1/kg and higher in females and from 35 mg FB1/kg in males. Serum cholesterol was elevated in both male and female mice, possibly due to FB1-induced changes in lipid metabolism in the liver and adrenals. Although bone marrow cell numbers were unchanged, increases in vacuolated myeloid cells and lymphocytes were observed in female mice. In general, the degree of changes observed indicate that mice are not as sensitive a model of FB1 toxicity as rats.
Collapse
Affiliation(s)
- G S Bondy
- Toxicology Research Division, Food Directorate, Health Canada, Ottawa, Canada
| | | | | | | | | | | | | |
Collapse
|