Magainina

Le magainine sono una classe di peptidi antimicrobici scoperti in Xenopus laevis.^[1] I peptidi in questa classe sono cationici, generalmente mancano di una conformazione stabile in acqua anche se formano una α-elica anfipatica nelle membrane. Anche se il loro meccanismo d'azione contro i microrganismi non è del tutto chiaro, essi mirano a distruggere le membrane cellulari di un ampio spettro di batteri, protozoi e funghi.^[2]

Furono scoperti in maniera indipendente dai laboratori di Michael Zasloff al NIH e Dudley H. Williams all'Università di Cambridge.^[2] Il loro nome è stato dato da Zasloff in onore della parola ebraica "scudo", מגן māgēn (pronuncia in ebraico : magain).^[3]

Zasloff aiutò a fondare una società, la Magainin Pharmaceuticals (successivamente chiamata Genaera), atta a sviluppare medicinali a base di magainine.^[4] Un candidato promettente era un analogo della magainina classica, chiamato pexiganan (MSI-78), che la compagnia sviluppò come agente topico per le ulcere del piede diabetico infette. Tuttavia, nel 1999 la FDA ha respinto la domanda in quanto il pexiganan non era migliore dei trattamenti standard.^[2]^[5]^[6] Un'altra società, Dipexium Pharmaceuticals, ha in seguito condotto ulteriori studi clinici per lo stesso uso, falliti nel 2016 in fase III dei test clinici.^[7]

Note

^ (EN) Magainins, in Medical Subject Headings (MeSH), National Library of Medicine, 2009.
^ ^a ^b ^c Host-defense peptides in skin secretions of African clawed frogs (Xenopodinae, Pipidae), in General and Comparative Endocrinology, vol. 176, n. 3, May 2012, pp. 513–8, DOI:10.1016/j.ygcen.2011.10.010, PMID 22036891.
^ Interviewed in 1987, Zasloff explained: "I used it because it came from the skin and it was shielding, in my opinion. What the hell, I hadn't heard a Hebrew name in science before" ( Susan Okie, Frog's Skin Yields Powerful Antibiotic, in The Washington Post, July 30, 1987.). In a later interview, his wife, Barbara Zasloff, added: "Tradition would have it that he would have given it a Latin or Greek name. We both felt that he comes from a Hebrew tradition and it would be very appropriate to give it a Hebrew name" ( Susan Okie, A Man and His Frogs, in The Washington Post, February 16, 1988.).
^ John George, Biotech Genaera shutting down: Never brought drug to market, in Philadelphia Business Journal, April 29, 2009.
^ The big and small of drug discovery. Biotech versus pharma: advantages and drawbacks in drug development, in EMBO Reports, vol. 4, n. 2, February 2003, pp. 114–7, DOI:10.1038/sj.embor.embor748, PMID 12612596.
^ Pexiganan, su adisinsight.springer.com, AdisInsight. URL consultato il 16 January 2018.
^ Dipexium's Diabetic Foot Ulcer Candidate Fails Phase III Trials, in GEN, October 25, 2016.

Altri progetti

Wikimedia Commons contiene immagini o altri file su Magainina

Collegamenti esterni

(EN) magainin, su Enciclopedia Britannica, Encyclopædia Britannica, Inc.

[1] (EN) Magainins, in Medical Subject Headings (MeSH), National Library of Medicine, 2009.

[Conlon-2] Host-defense peptides in skin secretions of African clawed frogs (Xenopodinae, Pipidae), in General and Comparative Endocrinology, vol. 176, n. 3, May 2012, pp. 513–8, DOI:10.1016/j.ygcen.2011.10.010, PMID 22036891.

[3] Interviewed in 1987, Zasloff explained: "I used it because it came from the skin and it was shielding, in my opinion. What the hell, I hadn't heard a Hebrew name in science before" ( Susan Okie, Frog's Skin Yields Powerful Antibiotic, in The Washington Post, July 30, 1987.). In a later interview, his wife, Barbara Zasloff, added: "Tradition would have it that he would have given it a Latin or Greek name. We both felt that he comes from a Hebrew tradition and it would be very appropriate to give it a Hebrew name" ( Susan Okie, A Man and His Frogs, in The Washington Post, February 16, 1988.).

[4] John George, Biotech Genaera shutting down: Never brought drug to market, in Philadelphia Business Journal, April 29, 2009.

[5] The big and small of drug discovery. Biotech versus pharma: advantages and drawbacks in drug development, in EMBO Reports, vol. 4, n. 2, February 2003, pp. 114–7, DOI:10.1038/sj.embor.embor748, PMID 12612596.

[6] Pexiganan, su adisinsight.springer.com, AdisInsight. URL consultato il 16 January 2018.

[7] Dipexium's Diabetic Foot Ulcer Candidate Fails Phase III Trials, in GEN, October 25, 2016.

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