Mushroom toxins

This chapter provides an overview of our present knowledge on mushroom toxins, and discusses the toxins in order of importance. The chapter includes information on the mushroom species producing the toxin chemistry and detection of the toxin and the medical impact of the toxin, i.e., the symptoms produced, and the appropriate treatment of the poisoning. The information is based on several reviews (Spoerke and Rumack, 1994 Faulstich and Wieland, 1992 Wieland and Faulstich, 1983), which may be consulted for more details, as well as on data taken from the current literature. 

Fortunately, of the vast number of mushroom species that exists, only a few produce secondary metabolites that cause fatal poisonings. If toxins causing benign symptoms, such as abdominal pain and diarrhea, hallucinations, or alcohol incompatibility, are disregarded, the most significant mushroom toxins are the extremely hazardous compounds of amatoxins, orellanine, and, to a lesser extent, methylhydrazine and its derivatives. Consequently, there is only a... 

Lassen, J.F., Ravn, H.B. and Lassen, S.F. (1990). Hallucinogenic psilocybin containing mushrooms. Toxins contained in Danish wild mushrooms, Ugeskr Laeger., 152, 314-317. 

Children are also especially vnlnerable for a reason tonched npon in Chapter 2. Consider the family of mushroom toxins known as amatox-ins. Almost all mushroom-related deaths in North America are caused by these toxins, which are metabolic products of Amanita phalloides. These toxins are slightly unusual because symptoms appear only after 12 hours following ingestion they include vomiting, diarrhea, and very intense abdominal pain. Ultimately the toxins cause liver injury that can be serious enough to cause death. 

An example of a hallucinogen affecting mammalian herbivores is the isox-azole muscimol (fig. 11.13), a mushroom toxin. It is a y-aminobutyric acid agonist in the central nervous system of vertebrates. Muscimol s role in nature... 

Intravenous silymarin has been demonstrated to lower mortality from Amanita mushroom poisonings, but this formulation is available only in Europe. Animal studies have demonstrated hepatic protection against alcohol, acetaminophen, and mushroom toxins and protection against hepatic fibrosis with bile duct occlusion. There is also evidence of silybin protecting against cis-platin-induced nephrotoxicity in rats. It is not yet clear whether milk thistle extract offers any renal protection to humans. 

Robert W. Buck, M.D., "Mushroom Toxins—A Brief Review of the Literature," New England Journal of Medicine, 265, 1961, 681-86. 

Toxicants may have three effects on pulse rate bradycardia (decreased rate), tachycardia (increased rate), and arrhythmia (irregular pulse). Alcohols may cause either bradycardia or tachycardia. Amphetamines, belladonna alkaloids, cocaine, and tricyclic antidepressants (see imi-primine hydrochloride in Figure 6.12) may cause either tachycardia or arrhythmia. Toxic doses of digitalis may result in bradycardia or arrhythmia. The pulse rate is decreased by toxic exposure to carbamates, organophosphates, local anesthetics, barbiturates, clonidine, muscaric mushroom toxins, and opiates. In addition to the substances mentioned above, those that cause arrhythmia are arsenic, caffeine, belladonna alkaloids, phenothizine, theophylline, and some kinds of solvents. 

Amphetamines and cocaine (Figure 6.11), tricyclic antidepressants (see imiprimine hydrochloride in Figure 6.12), phenylcyclidines, and belladonna alkaloids at toxic levels increase blood pressure. Overdoses of antihypertensive agents decrease blood pressure, as do toxic doses of opiates, barbiturates, iron, nitrite, cyanide, and mushroom toxins. 

The actions of nicotine relate to its ability to activate one of the two groups of cholinergic receptors, the nicotinic receptors. Nicotine and a second substance, muscarine, a mushroom toxin, were known long before acetylcholine was identified as a neurotransmitter, and the receptors in the PNS were initially distinguished by... 

J. Hajslova, Toxins Part J-Mushroom Toxins. In Natural Toxic Compounds in Foods J. Davidek, Ed. CRC Boca Raton, FL, 1995 pp 137-143. 

A toxin is a specific protein produced by living organisms (e.g., mushroom toxin or tetanus toxin). 

Maurer, H.H., Schmidt, C.J., Weber, A.A., Kraemer, T. Validated electrospray LC MS assay for determination of the mushroom toxins alpha- and beta-amanitin in urine after immunoaffinity extraction. J. Chromatogr. B Biomed. Sci. Appl. 748, 125-135 (2000)... 

Buck RW (1961) Mushroom toxins - A brief review of the literature. New England Journal of Medicine 265 681-686. 

Gundala, S., Wells, L.D., Milliano, M.T., Talkad, V., Luxon, B.A. and Neuschwander-Tetri, B.A. (2004) The hepatocellular bile acid transporter Ntcp facilitates uptake of the lethal mushroom toxin alpha-amanitin. Archives of Toxicology, 78, 68-73. 

The ester enolate Claisen rearrangement of (Z)-crotyl /V-tm-Boc-glycinate has been applied to the synthesis of lactone hydrochloride 4, the hydrolysis product of the amanita mushroom toxins a- and / -amanitin487. The rearrangement and the iodolactonization of the A -phthaloyl derivative are the stereocontrolling steps in this reaction sequence. 

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