Plant Profiler

Jequirity (Abrus)


Jequirity (Abrus) Image
Synonyms / Common Names / Related Terms
Abrin, abrin A, abrin B, abrin C, abrus a chapelet, Abrus abrus (L.) W. Wight, Abrus cantoniensis, Abrus precatorius, Linn., Abrus pulchellus, abrus seed, aivoeiro, arraccu-mitim, ayurvedic phytomedicine, bead vine, black-eyed Susan, blackeyed Susan, Buddhist rosary bead, cain ghe, Carolina muida, colorine, coral bean, crab's eye, crabs eye, deadly crab's eye, Glycine abrus, L., graines reglisse, gunchi, gunja, hint meyankoku, hung tou, Indian bead, Indian licorice, Indian liquorice, jequerit, jequirity bean, jequirity seed, jumble beads, juquiriti, lady bug bean, lady bug seed, legume, Leguminosae (family), liane reglisse, love bean, lucky bean, ma liao tou, ojo de pajaro, paratella, paternoster, peonia de St. Tomas, peonia, peronilla, phytotoxin, Pois rouge, prayer beads, prayer head, precatory bean, rakat, reglisse, rosary beads, rosary pea, ruti, rutti, Seminole bead, tentos da America, temtos dos mundos, tento muido, to-azuki, tribal pulse, weather plant, weesboontje, wild licorice.

Mechanism of Action

Pharmacology:

  • Constituents: Abrus seeds constituents include abrin (toxic protein which is similar in structure and properties to ricin)5, abrin A, abrin B, abrin C, lectins7, phytotoxins6, abrine, abrus agglutinin, hyaphorine, precatorine, abruquinone A, abruquinone B, abruquinone D, abruquinone E, abruquinone F, triterpenoid saponin 1 triterpenoid saponin 2, and most of the essential amino acids, except cystine and threonine4.
  • Abrin (agglutinin, toxalbumin) is a potent plant toxin; microgram quantities are suficient to kill a man, and as in ricin lectin poisoning, there is no antidote. "Abrine" refers to a different chemical, N-Methyl-L-Tryptophan, and the two should not be confused.
  • Anti-allergies effects: The abruquinones A, B, D, and F of Abrus precatorius L. showed strong anti-allergies effects.1 The IC50 of abruquinones A, B, D, and F for the inhibition of superoxide formation were less than 0.3micrograms/mL, for the inhibition of the release of both beta-glucuronidase and lysozyme from rat neutrophils and the release of both beta-glucuronidase and histamine from mast cells were less than 1microgram/mL.
  • Anti-inflammatory effects: The abruquinones A, B, D, and F of Abrus precatorius L. showed strong anti-inflammatory effects.1 The IC50 of abruquinones A, B, D, and F for the inhibition of superoxide formation were less than 0.3micrograms/mL, for the inhibition of the release of both beta-glucuronidase and lysozyme from rat neutrophils and the release of both beta-glucuronidase and histamine from mast cells were less than 1microgram/mL.
  • Anti-leukemia effects: The effect of abrin A on the apoptosis induction in leukemic cells was dose- and time-dependent.2 The process was initiated 1 hour after abrin A application (before its penetrating into the cells) and was characterized with PSer translocation from the inner to the outer monolayer of plasma membrane, caspase activation on the first to second hour after beginning of treatment, with maximum on the third to fourth hour, and DNA fragmentation on the fourth to sixth hour, depending of the cell line. In HPB-ALL, no significant changes in PSer exposure on the cell surface were observed. The apoptosis progressed to DNA fragmentation in a dose-and time-dependent manner. It seems that the mechanisms of abrin A-induced apoptosis are different and the progress of apoptosis depends of the cell line. There was a very good positive correlation between the agglutinating activity of abrin A and development of apoptosis to DNA fragmentation. The time-dependent effects of abrin A on apoptosis as well as its time-dependent penetration into the cells suggest that the B-chain probably triggers the apoptosis, while the A-chain and breakage of the disulfide bond are responsible for its progress.
  • The cytoagglutinating activity of abrin B, a toxic lectin isolated from Abrus precatorius seeds, against cultured cell strains derived from acute lymphoblast leukemia (ALL) was investigated by visible (VIS) spectroscopy.3
  • Anti-platelet effects: The abruquinones A, B, and D of Abrus precatorius L. exhibited remarkable inhibitory effects on the platelet aggregation.1 The IC50 of abruquinones A and B for the inhibition of the platelet aggregation induced by arachidonic acid (AA) and collagen were less than 5micrograms/mL, and of abruquinone D, was less than 10micrograms/mL for that induced by AA.
  • Anti-protein synthesis effects: At the cellular level, abrin inhibits protein synthesis, thereby causing cell death.5 Many of the features observed in abrin poisoning can be explained by abrin-induced endothelial cell damage, which causes an increase in capillary permeability with consequent fluid and protein leakage and tissue edema or vascular leak syndrome.
  • Abrin A consists of A-chain with N-glycosidase activity, which inhibits protein synthesis, and lectin-like B-chain responsible for binding with cell-surface receptors and penetrating of abrin A molecule into the cells.2 As a lectin component, the B-chain can also participate in cell signal transduction.
  • Anti-sperm motility: A study examined the inhibitory effects of a methanol extract of Abrus precatorius seeds on the motility of washed human spermatozoa. The extract caused a concentration-related impairment of percentage sperm motility; with the EC50 concentration being 2.29mg/mL. This effect on motility was essentially irreversible. With the highest concentration tested (20.0mg/mL), the onset of the antimotility action was almost immediate. In addition, this concentration impaired the functional integrity of the plasma membrane (hypoosmotic swelling test) and viability (nigrosin-eosin stain) of spermatozoa. In contrast, with a lower concentration (5.0mg/mL), such effects were not evident. It is concluded that at the lower concentrations the antimotility action may result from a rise in intracellular calcium (not via influx) and/or a decline in cAMP content and/or enhanced generation of a reactive oxygen species.8
  • Researchers from the University of Colombo in Sri Lanka produced a methanolic extract from the seeds of Abrus precatorius to determine if it could produce an inhibitory effect on sperm motility. Concentrations of 1.25 and 2.5mg/mL of the extract significantly reduced motility after 60 minutes of incubation (p=0.001).8 Further concentrations of 5mg/mL caused the same significant level of impairment as 1.25 and 2.5mg/mL concentrations (p=0.001), but at 30 minutes rather than 60 minutes. Moreover concentrations of 10 and 20mg/mL significantly prevented motility almost immediately (p=0.001). In fact, at 20mg/mL concentrations, motility completely stopped at 0 minutes in 3 of the 9 samples and, by 5 minutes, it stopped motility in an additional 5 samples. None of the samples exhibited mobile sperm at 15 minutes at 20mg/mL concentrations. In addition, after washing, the researchers observed that the antimotility effect was basically irreversible. The highest concentration (20mg/mL) impaired the functional integrity of the plasma membrane and viability of spermatozoa. This did not happen at the lower concentrations. Instead, the researchers found that a rise in intracellular calcium, and/or a fall in cAMP content, and/or enhanced generation of a reactive oxygen species may have caused the antimotility action at the lower concentrations.
  • Anti-tumor effects: Abrin, a galactose specific lectin was purified using sepharose 4B affinity column from seeds of Abrus precatorius.9 It exhibited anti-tumor activity in mice when used at a sublethal dose of 7.5micrograms/kg every alternate day for 10 days. Both intralesional and intraperiloneal (i.p.) administration of abrin was effective in reducing solid tumor mass development induced by Dalton's Lymphoma Ascites (DLA) and Ehrlich's Ascites Carcinoma (EAC) cells. DLA cell line was more sensitive to abrin than EAC. Abrin when injected i.p. increased the life span of ascites tumor bearing mice. Abrin when used simultaneously with tumor cells brought about maximum antitumor effect. On developed tumor masses, abrin administration brought about significant reduction in tumor volume, especially in DLA induced tumors. Prophylactic administration of abrin was found ineffective.
  • Toxic effects: The biological properties of abrin A were found to be similar to the better studied abrus protein, abrin C, in that it is toxic to cell-free protein synthesis and binds D-galactose.10 The evidence suggests that the two abrins may have the same mechanisms of toxic action.

Pharmacodynamics/Kinetics:

  • Insufficient available evidence.

References

  1. Kuo, S. C., Chen, S. C., Chen, L. H., Wu, J. B., Wang, J. P., and Teng, C. M. Potent antiplatelet, anti-inflammatory and antiallergic isoflavanquinones from the roots of Abrus precatorius. Planta Med 1995;61(4):307-312. 7480175
  2. Ohba, H., Moriwaki, S., Bakalova, R., Yasuda, S., and Yamasaki, N. Plant-derived abrin-a induces apoptosis in cultured leukemic cell lines by different mechanisms. Toxicol Appl Pharmacol 3-1-2004;195(2):182-193. 14998684
  3. Ohba, H., Toyokawa, T., Yasuda, S., Hoshino, T., Itoh, K., and Yamasaki, N. Spectroscopic analysis of the cytoagglutinating activity of abrin-b isolated from Abrus precatorius seeds against leukemic cells. Biosci Biotechnol Biochem 1997;61(4):737-739. 9145534
  4. Rajaram, N. and Janardhanan, K. The chemical composition and nutritional potential of the tribal pulse, Abrus precatorius L. Plant Foods Hum Nutr 1992;42(4):285-290. 1438071
  5. Dickers, K. J., Bradberry, S. M., Rice, P., Griffiths, G. D., and Vale, J. A. Abrin poisoning. Toxicol Rev 2003;22(3):137-142. 15181663
  6. Kinamore, P. A., Jaeger, R. W., and de Castro, F. J. Abrus and ricinus ingestion: management of three cases. Clin Toxicol 1980;17(3):401-405. 6108823
  7. Ramos, M. V., Sampaio, A. H., Cavada, B. S., Calvete, J. J., Grangeiro, T. B., and Debray, H. Characterization of the sugar-binding specificity of the toxic lectins isolated from Abrus pulchellus seeds. Glycoconj J 2001;18(5):391-400. 11925506
  8. Ratnasooriya, W. D., Amarasekera, A. S., Perera, N. S., and Premakumara, G. A. Sperm antimotility properties of a seed extract of Abrus precatorius. J Ethnopharmacol 1991;33(1-2):85-90. 1943179
  9. Ramnath, V., Kuttan, G., and Kuttan, R. Immunopotentiating activity of abrin, a lectin from Abrus precatorius Linn. Indian J Exp Biol 2002;40(8):910-913. 12597021
  10. Herrmann, M. S. and Behnke, W. D. A characterization of abrin A from the seeds of the Abrus precatorius plant. Biochim Biophys Acta 2-27-1981;667(2):397-410. 7213807




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