Descoberta proteína que impede calvície e cabelos brancos  08/08/11
Autor: Pesquisando Ciências | Publicado: 2011-08-08T14:59:00-07:00

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Descoberta proteína que impede calvície e cabelos brancos
08/08/11Wnt é essencial para o crescimento de fios capilares e produção de pigmentos 

Um estudo inédito com células estaminais de folículos capilares poderá fazer muito feliz para quem sofre de gerascofobia (medo de envelhecer). A investigação norte-americana permitiu a descoberta de uma proteína responsável pelo crescimento e coloração dos cabelos. Há já décadas que os cientistas sabem que as células dos folículos capilares e dos melanócitos, as células produtoras de pigmento, interagem de forma a produzirem o cabelo colorido. Até agora, no entanto, ninguém sabia exatamente como. 

No trabalho publicado na «Cell», Mayumi Ito, da Universidade de Nova York, descobriu que uma proteína conhecida como Wnt tem um papel essencial no processo. O estudo feito em ratos mostrou exatamente como os caminhos sinalizadores da proteína Wnt permitem que as células-tronco dos folículos e dos melanócitos trabalhem juntas para gerar o crescimento capilar e produzir pigmentos. 
A investigação mostrou que a anormalidade ou a ausência de Wnt inibe o surgimento de novos fios e impede a formação de cor. Além de indicar uma possível forma de tratamento para calvície e cabelos grisalhos, o estudo também pode ajudar a combater doenças graves, como o melanoma ou cancro da pele. 

Existem vários tipos de células-estaminais com potencial de regeneração, mas este método descoberto nos fios de cabelo, podem dar pistas importantes para regenerar órgãos mais complexos. Além disso, ajuda a compreender doenças nas quais os melanócitos estão envolvidos.
Origem: Biologias
Fonte(Referências): http://www.cienciahoje.pt/index.php?oid=50403&amp;op=all 
Ciência Hoje