Les cegueres “equivalents al dany per llum” s\u00f3n aquelles causades per algun tipus de desajust fisiol\u00f2gic que comporta que les c\u00e8l\u00b7lules receptores de llum de la retina, cons i bastons, estiguin sempre excitades, el que acaba provocant la mort cel\u00b7lular, i per tant, la ceguera. L\u2019excitabilitat d’aquestes c\u00e8l\u00b7lules es regeix per l’entrada o el fre al pas d’ions a trav\u00e9s dels canals de la superf\u00edcie. A les cegueres “equivalents al dany per llum” els canals romanen sempre tancats, el que resulta en una baixada cr\u00f2nica del calci dins de les c\u00e8l\u00b7lules.<\/p>\n
L’equip de la Dra. Ana M\u00e9ndez de l’Institut de Recerca Biom\u00e8dica de Bellvitge (IDIBELL), i de la Facultat de Medicina i Ci\u00e8ncies de la Salut de la Universitat de Barcelona, \u200b\u200bva postular en treballs previs que els sensors de calci GCAP podrien ser els mediadors de la mort cel\u00b7lular en les c\u00e8l\u00b7lules fotoreceptores davant aquesta baixada prolongada del calci.<\/p>\n
L\u2019Amaurosi Cong\u00e8nita de Leber (LCA12), \u00e9s una d’aquestes cegueres “equivalents a dany per llum”. \u00c9s causada per la mutaci\u00f3 del gen RD3, el que acaba provocant el tancament dels canals i la baixada cr\u00f2nica del calci. En aquest estudi es demostra, que en models animals de LCA12, si tamb\u00e9 s’eliminen els sensors de calci GCAP, l’aparici\u00f3 de la ceguera es retarda significativament. El que s’ha aconseguit \u00e9s evitar la mort de les c\u00e8l\u00b7lules fotoreceptores eliminant la prote\u00efna que detecta els nivells baixos de calci.<\/p>\n
En aquest estudi s’ha vist que, en les cegueses equivalents a dany per llum, els sensors GCAP es “bloquegen” en el seu estat actiu i s’acumulen en un compartiment incorrecte de la c\u00e8l\u00b7lula. Els resultats apunten que les GCAPs en el context de LCA12 activen algun mecanisme dins la c\u00e8l\u00b7lula que en \u00faltim terme condueix a l\u2019estr\u00e8s del reticle endoplasm\u00e0tic i a l’apoptosi.<\/p>\n
La Dra. Ana M\u00e9ndez comenta que hi ha m\u00e9s de dos-cents gens associats a cegueses, en molts casos minorit\u00e0ries, i que aprendre a modificar cada un d’aquests gens pot resultar molt cost\u00f3s. La rellev\u00e0ncia d’aquest estudi rau en el fet que s’ha trobat un mecanisme de dany en el qual podrien convergir totes aquelles cegueses causades per mutacions que comporten a una baixada cr\u00f2nica del calci dins de la c\u00e8l\u00b7lula. Futurs treballs se centraran a caracteritzar el mecanisme pel qual es podria endarrerir o revertir aquestes patologies.<\/p>\n","protected":false},"excerpt":{"rendered":"
La LCA12 forma part de les cegueres heredit\u00e0ries m\u00e9s severes que es manifesten a edats molt primerenques. L’estudi d’un model animal d’aquest tipus de ceguera ha perm\u00e8s detectar les prote\u00efnes GCAP com a mediadores de la mort cel\u00b7lular en aquest tipus de cegueres. S’ha vist que l’eliminaci\u00f3 d’aquestes prote\u00efnes endarrereix l’aparici\u00f3 de la patologia. Aquest estudi desvela un mecanisme de dany sobre el qual actuar terap\u00e8uticament, per retardar la degeneraci\u00f3 retinal en LCA12 i, potencialment, en altres cegueres similars.<\/p>\n","protected":false},"author":6,"featured_media":12679,"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-opacity":"","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-opacity":"","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-opacity":"","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-opacity":"","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-opacity":"","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-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[347,340],"tags":[],"class_list":["post-7345","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bases-cellulars-i-moleculars-dels-trastorns-sensorials","category-neurociencies"],"publishpress_future_action":{"enabled":false,"date":"2024-11-24 16:54:23","action":"change-status","newStatus":"draft","terms":[],"taxonomy":"category"},"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts\/7345","targetHints":{"allow":["GET"]}}],"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=7345"}],"version-history":[{"count":0,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/posts\/7345\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/media\/12679"}],"wp:attachment":[{"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/media?parent=7345"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/categories?post=7345"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/idibell.cat\/wp-json\/wp\/v2\/tags?post=7345"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}