La s\u00edndrome de Down (SD) \u00e9s una condici\u00f3 associada a la trisomia del cromosoma 21 hum\u00e0. Com a resultat d’aquesta alteraci\u00f3 gen\u00e8tica, els individus amb SD presenten un exc\u00e9s de dosi g\u00e8nica de determinats gens que acaba conduint a un increment an\u00f2mal de productes g\u00e8nics (prote\u00efnes). Aquests canvis moleculars provoquen importants afectacions de la funci\u00f3 neuronal i, m\u00e9s concretament, de la forma amb qu\u00e8 les neurones i els circuits neuronals es comuniquen.<\/p>\n
\u00a0<\/p>\n
L\u2019estructura cel\u00b7lular que permet la comunicaci\u00f3 entre les neurones del cervell s\u2019anomena sinapsi. I les mol\u00e8cules responsables de la transmissi\u00f3 d\u2019informaci\u00f3 reben el nom de neurotransmissors. Un dels principals sistemes de neurotransmissi\u00f3 excitat\u00f2ria al nostre cervell \u00e9s la sinapsi glutamat\u00e8rgica, \u00e9s a dir, la que utilitza el glutamat (un amino\u00e0cid) per transmetre la informaci\u00f3 (activaci\u00f3) d\u2019una neurona a l\u2019altra.<\/p>\n
\u00a0<\/p>\n
Focalitzant el seu estudi en un subtipus de receptors de glutamat presents a les sinapsis (anomenats receptors de tipus NMDA), investigadors de l\u2019Institut d\u2019Investigaci\u00f3 Biom\u00e8dica de Bellvitge (IDIBELL) i de la Universitat de Barcelona han descrit la signatura bioqu\u00edmica de les sinapsis glutamat\u00e8rgiques en SD en ratolins. Liderat pel Dr. Xavier Altafaj, el treball, que ha estat publicat a la revista Frontiers in Molecular Neuroscience, s\u2019ha dut a terme, en gran mesura, gr\u00e0cies a un ajut concedit per la Fundaci\u00f3 La Marat\u00f3 de TV3, que en la passada edici\u00f3 de 2015 dedic\u00e0 el seu programa a les malalties neurodegeneratives.<\/p>\n
\u00a0<\/p>\n
Segons el Dr. Altafaj, \u201cen el nostre darrer treball hem caracteritzat l’enorme complexitat proteica dels diferents compartiments sin\u00e0ptics de les neurones de l\u2019hipocamp de ratolins que recapitulen la SD humana\u201d. Per a realitzar l\u2019estudi, els investigadors han posat a punt un protocol bioqu\u00edmic d’alta precisi\u00f3 i han utilitzat t\u00e8cniques d\u2019espectrometria de masses d’\u00faltima generaci\u00f3, que els han perm\u00e8s identificar un nombre molt elevat de modificacions post-traduccionals dels receptors de glutamat, b\u00e0sicament el seu patr\u00f3 de fosforilaci\u00f3 (l\u2019anomenat fosfoproteoma). Paral\u00b7lelament, s’ha identificat un conjunt d’enzims (prote\u00efnes quinasa i fosfatasa) que podrien ser els responsables d’aquest patr\u00f3 alterat de fosforilaci\u00f3 dels receptors de glutamat. Conjuntament, les dades obtingudes indiquen el paper clau que juguen els receptors de glutamat (i llurs desregulacions) en la patofisiologia de la s\u00edndrome de Down, alhora que permeten identificar noves dianes terap\u00e8utiques que seran explorades en futurs estudis.<\/p>\n
\u00a0<\/p>\n
El grup del Dr. Altafaj t\u00e9 una llarga traject\u00f2ria en l’estudi de les bases moleculars de la SD, i al llarg dels darrers anys s’ha centrat en desxifrar les alteracions de la sinapsi glutamat\u00e8rgica. Els estudis recents del grup de recerca del Dr. Altafaj van mostrar que els nivells de receptors de tipus NMDA es troben desregulats en models murins de s\u00edndrome de Down, com a conseq\u00fc\u00e8ncia directa de la sobreexpressi\u00f3 de determinats gens candidats de la SD. Aquests treballs, junt amb els indicis d’altres grups de recerca, van dur a formular la hip\u00f2tesi que l’alteraci\u00f3 dels receptors de glutamat pot jugar un paper clau en les alteracions de la funci\u00f3 neuronal associades a la SD.<\/p>\n","protected":false},"excerpt":{"rendered":"
L\u2019estudi s\u2019ha fonamentat en t\u00e8cniques punteres de fosfoprote\u00f2mica, i s\u2019ha dut a terme gr\u00e0cies a un ajut concedit per la Fundaci\u00f3 La Marat\u00f3 de TV3<\/p>\n","protected":false},"author":6,"featured_media":10560,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"no-sidebar","site-content-layout":"page-builder","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[340,344],"tags":[],"publishpress_future_action":{"enabled":false,"date":"2024-05-08 23:08:09","action":"change-status","newStatus":"draft","terms":[],"taxonomy":"category"},"_links":{"self":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts\/7605"}],"collection":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/comments?post=7605"}],"version-history":[{"count":0,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts\/7605\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/media\/10560"}],"wp:attachment":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/media?parent=7605"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/categories?post=7605"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/tags?post=7605"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}