Trichothecene-induced hemolysis. I. The hemolytic activity of T-2 toxin.

In the present investigation, the hemolytic properties of T-2 toxin were examined. Tests with different concentrations of T-2 toxin showed that essentially complete hemolysis of rat erythrocytes commenced after a lag period, the length of which depended on the concentration of toxin. Comparison of the characteristics of hemolysis caused by T-2 toxin, saponins, H2O2, and polyoxyethylene surfactants showed great similarity between T-2 toxin and the latter two which proceed by a free radical mechanism. The same mechanism was suggested for hemolysis caused by T-2 toxin on the basis of the additional following observations: (1) darkness inhibited hemolysis; (2) specific free radical scavengers, i.e., vitamin E, mannitol, and histidine, inhibited hemolysis caused by T-2 toxin.

Mycotoxicosis caused by either T-2 toxin or diacetoxyscirpenol in the diet of broiler chickens.

Seven-day-old male broiler chickens were fed either T-2 toxin or diacetoxyscirpenol at 4 and 16 ppm for 21 days and had reductions of feed consumption and of weight gain. Focal, yellow, oral plaques developed by day 2 and were located around salivary duct openings on the palate, tongue, and buccal floor. The plaques progressed to raised, yellowish-gray crusts which covered ulcers. Microscopically, the ulcers had a base of granulation tissue and inflammatory cells, and the crusts comprised exudate, bacterial colonies and feed components. T-2 toxin and diacetoxyscirpenol produced similar effects at these concentrations. Comparable lesions also occurred in chickens fed T-2 toxin at 50, 100, or 300 ppm for 7 days. Six of 10 chickens died in the 300-ppm group which received an average daily exposure of about 10 mg T-2 toxin/kg body weight. In dead chickens, the lymphoid and hematopoietic tissues and alimentary mucosa were necrotic. Necrosis was seen less frequently in the liver, kidney and the feather. Survivors of the 7-day studies had atrophied lymphoid organs and were anemic.

Mycotoxicosis produced in broiler chickens by multiple doses of either T-2 toxin or diacetoxyscirpenol.

T-2 toxin, a 12, 13-epoxytrichothecene mycotoxin, was given by crop gavage to 7-day-old male broiler chickens as 14 daily doses of 1.5, 2.0, 2.5, and 3.0 mg/kg body weight/day. Diacetoxyscirpenol, also an epoxytrichothecene, was given at doses of 2.5, 3.0,and 3.5 mg/kg/day. Some chickens became dehydrated and emaciated and died. In survivors, body weight and haematocrit were reduced, the feathers were malformed, and the beak and legs were pale yellow. At necropsy, the lymphoid organs were atrophic, bone marrow was pale red or yellow, the liver was discoloured yellow, and the crop mucosa was ulcerated. Microscopic lesions included necrosis and cell depletion in lymphocytic and haematopoietic tissues, and necrosis of hepatocytes, bile ductule epithelium, enteric mucosa, and germinal regions of feather barbs. Other hepatic lesions were fatty change of hepatocytes and hyperplasia of bile ductules. Thyroid follicles were small, contained pale colloid and had tall epithelial cells. T-2 toxin was more detrimental than diacetoxyscirpenol to lymphocytic and haematopoietic tissues.

Cardiovascular lesions and various tumors found in rats given T-2 toxin, a trichothecene metabolite of Fusarium.

White rats given intragastrically 3alpha-hydroxy-4beta,15-diacetoxy-8alpha-(3-methylbutyryloxy)-12,13-epoxy-tricholthec-9-en (T-2 toxin), a trichothecene metabolite of several Fusarium species, developed various acute and chronic, topical and systemic lesions. The rats that survived 12 to 27.5 months after the first of three to eight doses of T-2 toxin (0.2 to 4 mg/kg body weight) alone or in conjunction with nicotinamide given i.p. (200 to 250 mg/kg body weight) developed cardiovascular lesions of various degrees of severity and/or tumors, benign and malignant, of the digestive tract and of the brain. T-2 toxin is known occasionally to contaminate cereals and other agricultural products, harvested or stored under damp and cold conditions. T-2 toxin was responsible for an often fatal disease in humans, known in the U.S.S.R. as "alimentary toxic aleukia," and also for outbreaks of hemorrhagic mycotoxicoses in livestock in various countries. T-2 toxin and other Fusarium mycotoxins may be involved in the etiology of cardiovascular lesions and of certain tumors considered as "spontaneous" in animals and humans.

Irreversible depigmentation of dark mouse hair by T-2 toxin (a metabolite of Fusarium sporotrichioides) and by calcium pantothenate.

T-2 toxin, a trichothecene metabolite of several Fusarium spp. causes depigmentation of dark mouse hair at the site of its application. Calcium pantothenate, though usually considered as antigreying factor, caused depigmentation at the site of its i.p. injections, at high concentration.

Comparative study of the yield of T-2 toxic produced by Fusarium poae, F. sporotrichioides and F. sporotrichioides var. tricinctum strains from different sources.

Eleven strains of Fusarium poae and F. sporotrichioides from the U.S.S.R. and 7 strains of these species and one of F. sporotrichioides var. tricinctum from U.S.A. and France have been compared as to their capacity to yield T-2 toxin. The presence of this toxin was confirmed by thin layer chromatography, gas liquid chromatography and mass spectroscopy. The strains which came from the U.S.S.R. and were originally involved in causing Alimentary Toxic Aleukia (ATA), produced several times more T-2 toxin than the others. We assume that the ability of the U.S.S.R. strains to produce much more T-toxin is due to the different ecological conditions under which they were first isolated. The remarkable maintenance of so high a level of toxin production over more than 30 years of culturing is worthy of note.

Screeing of toxic isolates of Fusarium poae and Fusarium sporotrichiodes involved in causing alimentary toxic aleukia.

A total of 131 isolates of Fusarium poae and F. sporotrichioides from overwintered cereals, which were associated with the alimentary toxic aleukia toxicoses in the Soviet Union, were tested for their ability to produce T-2 toxin [4 beta, 15 diacetoxy-8alpha-(3-methylbutyryloxy)-12,13-epoxytrichothec-9-en 3alpha-ol]. The presence of T-2 toxin was determined by thin-layer chromatography, gas-liquid chromatography, spectroscopic analyses, and the rabbit skin test. A good correlation was demonstrated between T-2 toxin dectetion by thin-layer chromatography and inflammatory skin reactions of rabbits.

Taxonomic study of fusaria of the sporotrichiella section used in recent toxicological work.

Eight isolates of Fusarium of the Sporotrichiella section were critically studied as to their taxonomic position. Most of these isolates had been used for comprehensive toxicological work on mycotoxin effects on animals, chiefly in the United States and Japan. Isolates NRRL 3299 and NRRL 3287, supplied from the United States, were determined to be Fusarium poae. Isolates NRRL 3249, NRRL 5908, 2061-C, and YN-13 from the United States and isolate T-2 from South Africa belonged to Fusarium sporotrichioides. Isolate NRRL 3509 belonged to F. sporotrichioides var. tricinctum. The relevance of recent toxicological work with these isolates on animals to earlier work on alimentary toxic aleukia is discussed in light of the above identifications.

Effects of light, temperature, and pH value on aflatoxin production in vitro.

In the complete absence of light, an isolate of Aspergillus flavus produced up to 170,000 pg aflatoxin per g, whereas the incubation of the fungus in light caused a reduction (35,000 pg/g) of the toxin synthesis.