Abrin treatment

This toxic protein is contained in caster seeds but does not pass into the oil. Similar phytotoxins occur in croton seeds (Crotin) jequirity seeds (Abrin) the bark of the locust tree, Robinia pseudo-acacia (Robin) and in the seeds of some leguminous plants (Phasin). The last is but weakly toxic. Ricin is responsible for the toxic effects on eating castor seeds 5 or 6 of these are fatal to a child, 20 to adults, and 3 or 4 seeds may cause violent gastroenteritis with nausea, headache, persistent vomiting, colic, sometimes bloody diarrhea, thirst, emaciation, and great debility. The symptoms usually do not set in until after several days. More severe intoxications cause small frequent pulse, cold sweat, icterus, and convulsions. Death occurs in 6 to 8 d, from the convulsions or from exhaustion. The fatality rate is about 6%. This low fatality rate is due to the destruction of the poison in the alimentary canal. The treatment would be evacuant and symptomatic. Usually, 3 to 10 d are required to complete recovery. 

The constitution of abrine was proved by methylation with methyl iodide and methanolic sodium hydroxide, which gave the same methyl ester methiodide as did similar treatment of L-tryptophan (15). Since the product was almost completely racemized (16), this did not establish the configuration of the asymmetric center. The configurational identity of abrine and L-tryptophan was proved by Cahill and Jackson (16), who obtained the same optically pure methyl betaine (II) from both abrine and L-tryptophan by methylation with methyl iodide and methanolic sodium hydroxide. Under the appropriate conditions, the racemic methyl ester methiodide crystallized out, and was removed the methyl bfetaine (II) which remained unesterified also escaped racemization, and was recovered from the mother liquors. 

Human parenteral toxicity for abrin is approximately 0.1-1 Jig/kg (Romano et al, 2007). However, based on clinical trials on abrin-immunotoxin use for cancer treatment, the human minimum lethal dose by intravenous injection was estimated to be >0.3 Jig/kg without occurrence of serious adverse effects (Gill, 1982). 

There is no specific treatment for ricin or abrin. Therefore the only recommendation is to rid the body of the toxins as quickly as possible. Ricin and abrin poisoning is treated by giving victims the appropriate supportive medical care to... 

Interestingly, the hope for a vaeeination in the treatment against abrin toxieity may be not that far away. In a reeent in vitro and in vivo study, antibodies speeifie to the reeombi-nant abrin A-ehain were shown to reseue eells from toxieity. Importantly, the antibody also proteeted miee from lethal doses of the toxin. The neutralizing effeet of the antibody... 

Chemical Abstracts Service Registry Number CAS 1393-62-0. Abrin is a toxalbumin similar in structure, absorption, and mechanism of action to ricin but is found not in castor beans but rather in jequirity beans. No reports of its use as a battlefield or terrorist agent exist, but in mice it is 75 times more potent than ricin. No specific treatment is available. Both ricin and abrin are type 2 ribosomal inhibitory proteins (RIPs) the other potent toxins in this class are Eranthis hyemalis lectin (EHL) from winter aconite, modeccin and volkensin from African succulents, and viscumin from mistletoe. 

Abrin has some potential medical uses, such as in treatment to kill cancer cells. 

Phytohaemagglutinins.—Abrin, ricin, and their isolated A and B chains have been subjected to various chemical treatments and the effect of these on the biological activity of the lectins assessed. Reductive methylation, periodate oxidation, or succinylation of abrin or ricin reduced the toxicity and haemagglutinating ability of the former but not the latter. Treatment with A-acetylimidazole or A-bromosuccinimide resulted in strongly reduced toxicity of abrin and ricin, while 2-hydroxy-5-nitrobenzyl bromide had much less effect. 

Abrin is a natural poison found in the seeds of a plant called the rosary pea or jequirity pea (Abrus precatorius). It is similar to ricin, although it is about 75 times more poisonous. Like ricin it is referred to as a toxalbumin, destroying ribosomes, which are responsible for protein synthesis, leading to cell death and tissue damage. Abrin has some potential medical uses, such as in treatment to kill cancer cells. To date, abrin is not known to have been used as a terrorist weapon although, like ricin, its highly toxic nature lends itself well to this purpose. 

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