{"id":70729,"date":"2026-05-12T10:06:21","date_gmt":"2026-05-12T10:06:21","guid":{"rendered":"https:\/\/medsbase.com\/?post_type=product&#038;p=70729"},"modified":"2026-05-21T07:14:10","modified_gmt":"2026-05-21T07:14:10","slug":"gdf-8","status":"publish","type":"product","link":"https:\/\/medsbase.com\/cs\/product\/gdf-8\/","title":{"rendered":"GDF-8 (Myostatin)"},"content":{"rendered":"<p><!-- medsbase-tldr-answer --><\/p>\n<div style=\"background: #fff8e1; border-left: 4px solid #f5a623; padding: 18px 22px; margin: 18px 0; border-radius: 4px;\">\n<h3 style=\"margin: 0 0 8px 0; font-size: 16px; color: #1a4a6b;\">Rychl\u00e1 odpov\u011b\u010f \u2014 Co je GDF-8 (myostatin)?<\/h3>\n<p style=\"margin: 0;\"><strong>GDF-8<\/strong> (Growth\/Differentiation Factor 8), tak\u00e9 naz\u00fdvan\u00fd <strong>myostatin<\/strong>, je rekombinantn\u00ed protein ze superrodiny TGF-\u03b2 a hlavn\u00ed endogenn\u00ed negativn\u00ed regul\u00e1tor kostern\u00ed svalov\u00e9 hmoty. Ztr\u00e1tov\u00e9 mutace zp\u016fsobuj\u00ed zn\u00e1m\u00fd fenotyp \u201cdvojit\u00e9ho osvalen\u00ed\u201d u my\u0161\u00ed, skotu, ps\u016f a jednoho zdokumentovan\u00e9ho lidsk\u00e9ho p\u0159\u00edpadu. Ve zve\u0159ejn\u011bn\u00fdch v\u00fdzkumech se rekombinantn\u00ed GDF-8 pou\u017e\u00edv\u00e1 jako n\u00e1stroj pro stimulaci drah: indukci atrofick\u00fdch fenotyp\u016f, validaci antagonist\u016f myostatinu, jako je <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">follistatin 344<\/a>, a charakterizaci n\u00e1sledn\u00e9 signalizace Smad2\/Smad3. Dod\u00e1v\u00e1 se v lyofilizovan\u00fdch vialk\u00e1ch o obsahu 1 mg v\u00fdhradn\u011b pro laboratorn\u00ed v\u00fdzkum.<\/p>\n<\/div>\n<div class=\"medsbase-trust-strip\" style=\"background: #f4f8fb; border: 1px solid #d8e3eb; padding: 12px 16px; margin: 16px 0; border-radius: 4px; font-size: 14px;\"><strong>Co z\u00edsk\u00e1te s MedsBase:<\/strong> V\u00fdzkumn\u00fd lyofilizovan\u00fd rekombinantn\u00ed protein \u00b7 HPLC \u010distota \u226595 % (COA na vy\u017e\u00e1d\u00e1n\u00ed) \u00b7 Diskr\u00e9tn\u00ed teplotn\u011b stabiln\u00ed balen\u00ed \u00b7 Celosv\u011btov\u00e1 p\u0159eprava peptid\u016f \u00b7 1 400+ ov\u011b\u0159en\u00fdch <a href=\"https:\/\/medsbase.com\/cs\/reviews\/\">recenz\u00ed z\u00e1kazn\u00edk\u016f<\/a><\/div>\n<p class=\"medsbase-reship-line\" style=\"font-size: 14px; color: #444; margin: 8px 0 18px;\">\ud83d\udce6 Ka\u017ed\u00e1 objedn\u00e1vka je pokryta na\u0161\u00ed <a href=\"https:\/\/medsbase.com\/cs\/medsbase-re-shipment-assurance-policy\/\"><strong>Z\u00e1rukou op\u011btovn\u00e9ho odesl\u00e1n\u00ed<\/strong><\/a> \u2014 pokud va\u0161e z\u00e1silka nedoraz\u00ed do 20 pracovn\u00edch dn\u016f, p\u0159epos\u00edl\u00e1me ji.<\/p>\n<table class=\"medsbase-spec-table\" style=\"width: 100%; border-collapse: collapse; margin: 18px 0; font-size: 14px;\">\n<thead>\n<tr style=\"background: #2c7cb0; color: #fff;\">\n<th style=\"padding: 8px 12px; text-align: left; width: 30%;\">Specifikace<\/th>\n<th style=\"padding: 8px 12px; text-align: left;\">Detail<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>CAS \u010d\u00edslo<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">Form\u00e1ln\u011b neregistrov\u00e1no pro zral\u00fd dimer (rekombinantn\u00ed protein). K\u00f3dov\u00e1no genem MSTN; UniProt O14793<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>Typ<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">Rekombinantn\u00ed protein (ligand superrodiny TGF-\u03b2; zral\u00fd 109-aminokyselinov\u00fd C-termin\u00e1ln\u00ed disulfidem spojen\u00fd homodimer \u0161t\u011bpen\u00fd z 375-aa preproproteinov\u00e9ho prekurzoru)<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>item7<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">~25,8 kDa (zral\u00fd homodimer; ~12,9 kDa na monomerick\u00fd \u0159et\u011bzec)<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>Struktura<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">Zral\u00fd 109-aa monomer s kanonickou cystinovou uzlinou superrodiny TGF-\u03b2; dva monomery kovalentn\u011b spojen\u00e9 intermolekul\u00e1rn\u00ed disulfidovou vazbou za vzniku biologicky aktivn\u00edho homodimeru; vazebn\u00e9 plochy pro receptor interaguj\u00ed s ActRIIB<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>item11<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">Lyofilizovan\u00fd rekombinantn\u00ed protein (b\u00edl\u00fd a\u017e sv\u011btle \u017elut\u00fd)<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>item13<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">\u226595 % (ov\u011b\u0159eno HPLC, COA na vy\u017e\u00e1d\u00e1n\u00ed)<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>Skladov\u00e1n\u00ed<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">Lyofilizovan\u00fd: 2\u20138 \u00b0C (lednice) pro pracovn\u00ed z\u00e1sobu; \u221220 \u00b0C pro dlouhodob\u00e9 skladov\u00e1n\u00ed neotev\u0159en\u00fdch vialek. Rekonstituovan\u00fd: 2\u20138 \u00b0C, pou\u017e\u00edt do ~30 dn\u016f. Chr\u00e1nit p\u0159ed sv\u011btlem. Nen\u00ed vhodn\u00e9 zmrazovat a rozmrazovat rekonstituovan\u00fd roztok \u2014 rekombinantn\u00ed proteiny jsou obzvl\u00e1\u0161t\u011b citliv\u00e9 na denaturaci zp\u016fsobenou zmrazen\u00edm a rozmrazen\u00edm.<\/td>\n<\/tr>\n<tr style=\"background: #fff;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>Rozpustnost<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">Bakteriostatick\u00e1 voda (doporu\u010deno) nebo steriln\u00ed voda pro krat\u0161\u00ed dobu pou\u017eit\u00ed. Nosn\u00fd protein (BSA, 0,1 %) voliteln\u00fd pro pracovn\u00ed \u0159ed\u011bn\u00ed, aby se minimalizovaly ztr\u00e1ty adsorpc\u00ed.<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0; width: 30%;\"><strong>Pouze pro v\u00fdzkum<\/strong><\/td>\n<td style=\"padding: 8px 12px; border-bottom: 1px solid #e0e0e0;\">Pouze pro laboratorn\u00ed v\u00fdzkum. Nen\u00ed ur\u010deno pro diagnostick\u00e9 nebo terapeutick\u00e9 pou\u017eit\u00ed u lid\u00ed nebo zv\u00ed\u0159at.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><!-- \/medsbase-tldr-answer --><\/p>\n<h2>Co je GDF-8 (Myostatin)?<\/h2>\n<p><strong>GDF-8<\/strong> (Growth\/Differentiation Factor 8), b\u011b\u017en\u011b zn\u00e1m\u00fd jako <strong>myostatin<\/strong>, je \u010dlenem nadrodiny transformuj\u00edc\u00edho r\u016fstov\u00e9ho faktoru beta (TGF-\u03b2) a hlavn\u00edm fyziologick\u00fdm negativn\u00edm regul\u00e1torem hmotnosti kostern\u00edho svalstva. Poprv\u00e9 byl charakterizov\u00e1n McPherronem, Lawlerem a Leem (Nature 1997) jako sekretovan\u00fd protein, jeho\u017e c\u00edlen\u00e9 naru\u0161en\u00ed u my\u0161\u00ed vedlo k tvorb\u011b zv\u00ed\u0159at s dvou- a\u017e trojn\u00e1sobn\u011b v\u011bt\u0161\u00ed hmotnost\u00ed kostern\u00edho svalstva ne\u017e u kontroln\u00edch jedinc\u016f. Stejn\u00fd gen byl rychle identifikov\u00e1n jako p\u0159\u00ed\u010dina fenotypu \u201cdvojit\u00e9ho osvalen\u00ed\u201d u belgick\u00fdch modr\u00fdch a piemontsk\u00fdch krav, fenotypu Bully Whippet u dostihov\u00fdch chrt\u016f a jednoho zdokumentovan\u00e9ho lidsk\u00e9ho p\u0159\u00edpadu v\u00fdrazn\u00e9 infantiln\u00ed hypermuskulatury (Schuelke et al., NEJM 2004) \u2014 v\u0161echny tyto p\u0159\u00edpady nesly mutace MSTN s poruchou funkce.<\/p>\n<p>Zral\u00fd myostatin vznik\u00e1 posttransla\u010dn\u00edm zpracov\u00e1n\u00edm 375-aminokyselinov\u00e9ho preproproteinu: sign\u00e1ln\u00ed peptid je odstran\u011bn b\u011bhem sekrece, pot\u00e9 je prodomena (~243 aa) od\u0161t\u011bpena furinov\u00fdmi prote\u00e1zami, \u010d\u00edm\u017e se uvoln\u00ed aktivn\u00ed 109-aminokyselinov\u00fd C-termin\u00e1ln\u00ed zral\u00fd myostatin. Aktivn\u00ed forma je homodimer dvou zral\u00fdch monomerick\u00fdch \u0159et\u011bzc\u016f kovalentn\u011b spojen\u00fdch intermolekul\u00e1rn\u00ed disulfidovou vazbou, s apparentn\u00ed hmotnost\u00ed p\u0159ibli\u017en\u011b 25,8 kDa na neredukuj\u00edc\u00edm SDS-PAGE. Protein zauj\u00edm\u00e1 kanonickou TGF-\u03b2 cysteinovou uzlovou strukturu a v\u00e1\u017ee se s vysokou afinitou na aktivinov\u00fd receptor typu IIB (ActRIIB), \u010d\u00edm\u017e iniciuje Smad-zprost\u0159edkovanou signalizaci. Rekombinantn\u00ed GDF-8 je dod\u00e1v\u00e1n jako vysoce \u010dist\u00fd lyofilizovan\u00fd pr\u00e1\u0161ek pro rekonstituci s bakteriostatickou vodou. Myostatin nen\u00ed <strong>FDA, EMA, MHRA ani \u017e\u00e1dn\u00fdm jin\u00fdm v\u00fdznamn\u00fdm regul\u00e1torem pro terapeutick\u00e9 pou\u017eit\u00ed u lid\u00ed. V\u00fdzkumn\u00fd DSIP prod\u00e1van\u00fd zde je dod\u00e1v\u00e1n<\/strong> FDA, EMA, MHRA ani \u017e\u00e1dn\u00fdm jin\u00fdm v\u00fdznamn\u00fdm regul\u00e1torem schv\u00e1len pro lidsk\u00e9 terapeutick\u00e9 pou\u017eit\u00ed. V\u00fdzkumn\u00fd GDF-8 prod\u00e1van\u00fd zde je dod\u00e1v\u00e1n <strong>ur\u010den pouze pro laboratorn\u00ed v\u00fdzkum<\/strong> a nen\u00ed ur\u010den pro lidsk\u00e9 ani veterin\u00e1rn\u00ed pod\u00e1v\u00e1n\u00ed.<\/p>\n<h2>Mechanismus \u00fa\u010dinku \u2014 ActRIIB signalizace a osa Smad2\/Smad3<\/h2>\n<p>Co \u010din\u00ed GDF-8 mechanisticky v\u00fdjime\u010dn\u00fdm mezi ligandy nadrodiny TGF-\u03b2, je jeho <strong>dominantn\u00ed role jako tonick\u00fd brzda r\u016fstu sval\u016f<\/strong> prost\u0159ednictv\u00edm dob\u0159e popsan\u00e9ho t\u0159\u00edkrokov\u00e9ho sign\u00e1ln\u00edho kask\u00e1dov\u00e9ho mechanismu zdokumentovan\u00e9ho ve v\u00fdzkumn\u00fdch publikac\u00edch:<\/p>\n<ul>\n<li><strong>vazba na receptor ActRIIB a n\u00e1bor typu I receptor\u016f<\/strong> \u2014 Zral\u00fd myostatinov\u00fd homodimer se v\u00e1\u017ee na aktivinov\u00fd receptor typu IIB (ActRIIB) na povrchu kostern\u00edch svalov\u00fdch vl\u00e1ken a dal\u0161\u00edch bun\u011b\u010dn\u00fdch typ\u016f. ActRIIB je konstitutivn\u011b aktivn\u00ed serin\/threonin kin\u00e1za, kter\u00e1 po vazb\u011b myostatinu rekrutuje a trans-fosforyluje receptory typu I ALK4 (ActRIB) a ALK5 (T\u03b2RI). Stechiometrie ligand-receptor je 2:2:2 heterotetramer v aktivn\u00edm komplexu. Knockout ActRIIB produkuje fenotyp podobn\u00fd myostatinov\u00e9mu knockoutu, co\u017e potvrzuje identitu receptoru.<\/li>\n<li><strong>fosforylace Smad2\/Smad3 a nukle\u00e1rn\u00ed translokace<\/strong> \u2014 Fosforylovan\u00e9 receptory typu I ALK4\/ALK5 fosforyluj\u00ed receptorov\u011b regulovan\u00e9 Smady \u2014 konkr\u00e9tn\u011b Smad2 a Smad3 v myostatinov\u00e9 dr\u00e1ze. Fosfo-Smad2\/Smad3 tvo\u0159\u00ed heteromern\u00ed komplex se Smad4 (b\u011b\u017en\u00fd Smad) a translokuj\u00ed do j\u00e1dra, kde se v\u00e1\u017eou na Smad-v\u00e1zaj\u00edc\u00ed elementy v promotorech c\u00edlov\u00fdch gen\u016f a rekrutuj\u00ed transkrip\u010dn\u00ed kofaktory. Smad dr\u00e1ha je dominantn\u00ed sign\u00e1ln\u00ed v\u00fdstup pro myostatin v kostern\u00edm svalu.<\/li>\n<li><strong>downstream transkrip\u010dn\u00ed efekty \u2014 upregulace atrogin-1\/MuRF1 a suprese proteinov\u00e9 synt\u00e9zy<\/strong> \u2014 Nukle\u00e1rn\u00ed Smad komplex koordinuje transkrip\u010dn\u00ed program, kter\u00fd podporuje svalovou atrofii t\u0159emi konverguj\u00edc\u00edmi mechanismy: indukc\u00ed ubiquitin-lig\u00e1zov\u00fdch atrogen\u016f (atrogin-1 \/ Fbxo32 a MuRF1 \/ Trim63) pro urychlen\u00ed degradace protein\u016f; inhibic\u00ed Akt\/mTOR-zprost\u0159edkovan\u00e9 proteinov\u00e9 synt\u00e9zy prost\u0159ednictv\u00edm k\u0159\u00ed\u017eov\u00e9 komunikace s IGF\/inzulinovou osou; a supres\u00ed myogenn\u00edch regula\u010dn\u00edch faktor\u016f (MyoD, myogenin) pro zpomalen\u00ed satelitn\u00edmi bu\u0148kami \u0159\u00edzen\u00e9 opravy. \u010cist\u00fdm efektem je sn\u00ed\u017een\u00e1 akrece svalov\u00fdch protein\u016f a p\u0159i vysok\u00fdch d\u00e1vk\u00e1ch nebo chronick\u00e9 expozici zjevn\u00e1 atrofie.<\/li>\n<\/ul>\n<p>D\u016fle\u017eit\u00e9 pro v\u00fdzkumn\u00fd design je, \u017ee GDF-8 p\u016fsob\u00ed jako tonick\u00fd inhibitor za fyziologick\u00fdch podm\u00ednek \u2014 svalov\u00e1 hmota je regulov\u00e1na rovnov\u00e1hou mezi myostatinov\u00fdm tonem (atrofick\u00fdm) a IGF\/Akt\/mTOR signalizac\u00ed (anabolickou). Proto se <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">Follistatin 344<\/a> (antagonista myostatinu\/aktivinu) a rekombinantn\u00ed GDF-8 (samotn\u00fd agonista) pou\u017e\u00edvaj\u00ed ve svalov\u00e9m v\u00fdzkumu \u2014 antagonista odstran\u00ed brzdu, zat\u00edmco rekombinantn\u00ed ligand je experiment\u00e1ln\u00ed n\u00e1stroj, kter\u00fd kvantifikuje s\u00edlu brzdy a validuje antagonistickou aktivitu v testech vazby na receptor a reporterov\u00fdch bun\u011bk.<\/p>\n<h2>Publikovan\u00e9 v\u00fdzkumn\u00e9 aplikace<\/h2>\n<p>Rekombinantn\u00ed GDF-8 se pou\u017e\u00edv\u00e1 v laboratorn\u00edm v\u00fdzkumu ke zkoum\u00e1n\u00ed:<\/p>\n<ul>\n<li><strong>V\u00fdzkum svalov\u00e9 atrofie a \u00fabytku<\/strong> \u2014 in-vitro atrofick\u00e9 testy myotub\u016f, ex-vivo svalov\u00e9 prepar\u00e1ty, in-vivo pod\u00e1v\u00e1n\u00ed k indukci reprodukovateln\u00fdch atrofick\u00fdch fenotyp\u016f pro studium interven\u010dn\u00edch strategi\u00ed (McPherron et al., Nature 1997; Lee, Annu Rev Cell Dev Biol 2004)<\/li>\n<li><strong>Validace myostatinov\u00fdch antagonist\u016f<\/strong> \u2014 testy vazebn\u00e9 afinity, testy potence neutraliza\u010dn\u00edch protil\u00e1tek, testy obsazen\u00ed receptor\u016f pro programy objevov\u00e1n\u00ed l\u00e9k\u016f c\u00edlen\u00fdch na myostatinovou dr\u00e1hu; kanonick\u00fd v\u00fdzkumn\u00fd n\u00e1stroj pro validaci <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">follistatin 344<\/a>, rozpustn\u00e9 f\u00fazn\u00ed proteiny ActRIIB-Fc a protil\u00e1tky proti myostatinu<\/li>\n<li><strong>V\u00fdzkum signaliza\u010dn\u00ed dr\u00e1hy Smad2\/Smad3<\/strong> \u2014 kinetika fosforylace Smad, zobrazov\u00e1n\u00ed nukle\u00e1rn\u00ed translokace, report\u00e9rov\u00e9 testy s vazebn\u00fdm elementem Smad, interakce s dal\u0161\u00edmi \u010dleny TGF-\u03b2 dr\u00e1hy<\/li>\n<li><strong>V\u00fdzkum transkripce atrogen\u016f<\/strong> \u2014 anal\u00fdza promotoru atrogin-1 (Fbxo32) a MuRF1 (Trim63), aktivita ubiquitin-proteasomov\u00e9ho syst\u00e9mu, interakce s autof\u00e1gn\u00ed osou<\/li>\n<li><strong>Modely kachexie a sarkopenie<\/strong> \u2014 modely kachexie u hlodavc\u016f s n\u00e1dory, sarkopenie u st\u00e1rnouc\u00edch my\u0161\u00ed, atrofie indukovan\u00e1 denervac\u00ed \u2014 rekombinantn\u00ed GDF-8 pou\u017eit\u00fd k amplifikaci nebo replikaci fenotypu \u00fabytku svalov\u00e9 hmoty<\/li>\n<li><strong>V\u00fdzkum srde\u010dn\u00ed a dal\u0161\u00ed tk\u00e1n\u011b<\/strong> \u2014 myostatin je exprimov\u00e1n v ni\u017e\u0161\u00edch hladin\u00e1ch v srdci, tukov\u00e9 tk\u00e1ni a dal\u0161\u00edch tk\u00e1n\u00edch; publikovan\u00fd v\u00fdzkum zkoum\u00e1 \u00fa\u010dinky GDF-8 v modelech hypertrofie kardiomyocyt\u016f a biologii tukov\u00e9 tk\u00e1n\u011b<\/li>\n<li><strong>Srovn\u00e1vac\u00ed v\u00fdzkum TGF-\u03b2 superrodiny<\/strong> \u2014 porovn\u00e1n\u00ed s bl\u00edzce p\u0159\u00edbuzn\u00fdm GDF-11 (90% sekven\u010dn\u00ed identity v zral\u00e9 dom\u00e9n\u011b) a aktivinem A (v\u00e1\u017ee se na stejn\u00fd receptorov\u00fd syst\u00e9m); mechanistick\u00e1 anal\u00fdza receptorov\u00e9 selektivity<\/li>\n<li><strong>Inverzn\u011b-farmakologick\u00e9 p\u00e1rov\u00e1n\u00ed s Follistatinem 344<\/strong> \u2014 spole\u010dn\u00e1 administrace s <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">Follistatin 344<\/a> jako antagonistick\u00e1 slo\u017eka umo\u017e\u0148uje p\u0159\u00edm\u00e9 kvantifikov\u00e1n\u00ed vazebn\u00e9 stechiometrie myostatinu\/antagonisty a z\u00e1chranu GDF-8 indukovan\u00e9 atrofie ve v\u00fdzkumn\u00fdch modelech.<\/li>\n<\/ul>\n<p>Pro \u0161ir\u0161\u00ed kontext, kde se GDF-8 nach\u00e1z\u00ed v r\u00e1mci anabolick\u00e9ho\/svalov\u00e9ho v\u00fdzkumu, viz <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">Follistatin 344<\/a> jako kanonick\u00fd antagonista myostatinu, <a href=\"https:\/\/medsbase.com\/cs\/igf-1-lr3\/\">IGF-1 LR3<\/a> pro anabolickou slo\u017eku opa\u010dn\u00e9 dr\u00e1hy (p\u0159\u00edm\u00e1 agonie IGF-1R), a <a href=\"https:\/\/medsbase.com\/cs\/tb-500\/\">TB-500<\/a> pro v\u00fdzkum syst\u00e9mov\u00e9 regenerace sval\u016f a tk\u00e1n\u00ed. Prohl\u00e9dn\u011bte si cel\u00fd <a href=\"https:\/\/medsbase.com\/cs\/peptides\/\">katalog v\u00fdzkumn\u00fdch peptid\u016f<\/a> pro p\u0159\u00edbuzn\u00e9 slou\u010deniny.<\/p>\n<h2>Dostupn\u00e9 s\u00edly a koncentrace<\/h2>\n<p>MedsBase nab\u00edz\u00ed rekombinantn\u00ed GDF-8 (Myostatin) v lyofilizovan\u00fdch vialk\u00e1ch po 1 mg. Vialka je dostupn\u00e1 v balen\u00ed po 10 nebo 20 vialk\u00e1ch s \u00fapln\u00fdm n\u00e1vodem na rekonstituci:<\/p>\n<table style=\"width: 100%; border-collapse: collapse; margin: 16px 0;\">\n<thead>\n<tr style=\"background: #2c7cb0; color: #fff;\">\n<th style=\"padding: 10px; border: 1px solid #ddd; text-align: left;\">S\u00edla vialky<\/th>\n<th style=\"padding: 10px; border: 1px solid #ddd; text-align: left;\">Typick\u00fd v\u00fdzkumn\u00fd p\u0159\u00edpad u\u017eit\u00ed<\/th>\n<th style=\"padding: 10px; border: 1px solid #ddd; text-align: left;\">Velikosti balen\u00ed<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>1 mg<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Standardn\u00ed v\u00fdzkumn\u00e1 s\u00edla \u2013 vazebn\u00e9 testy, protokoly pro indukci atrofie, validace antagonist\u016f<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">10 nebo 20 vialek<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>GDF-8 je rekombinantn\u00ed homodimern\u00ed protein o hmotnosti ~25,8 kDa dod\u00e1van\u00fd v HPLC \u010distot\u011b \u226595%. Form\u00e1t 1 mg vialky pokr\u00fdv\u00e1 typick\u00e9 v\u00fdzkumn\u00e9 d\u00e1vkov\u00e9 rozmez\u00ed: nanomol\u00e1rn\u00ed pracovn\u00ed koncentrace pro in-vitro vazebn\u00e9 testy a testy na report\u00e9rn\u00edch bu\u0148k\u00e1ch spot\u0159ebuj\u00ed mal\u00e9 \u010d\u00e1sti vialky; in-vivo pod\u00e1v\u00e1n\u00ed u hlodavc\u016f pou\u017e\u00edv\u00e1 d\u00e1vky v mikrogramech na injekci, kter\u00e9 spot\u0159ebuj\u00ed v\u00edce vialky podle protokolu.<\/p>\n<h2>Srovn\u00e1n\u00ed \u2013 GDF-8 (Myostatin) vs Follistatin 344<\/h2>\n<p>Rekombinantn\u00ed GDF-8 a <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">Follistatin 344<\/a> jsou farmakologicky inverzn\u00ed p\u00e1r: GDF-8 je ligand a Follistatin 344 je protein s vysokou afinitou, kter\u00fd jej v\u00e1\u017ee. Ve v\u00fdzkumu jsou \u010dasto pou\u017e\u00edv\u00e1ny spole\u010dn\u011b, proto\u017ee funkci antagonisty lze kvantifikovat pouze v\u016f\u010di ligandu. Tento vztah je podobn\u00fd jin\u00fdm zn\u00e1m\u00fdm inverzn\u00edm p\u00e1r\u016fm ve farmakologii (nap\u0159. agonista + antagonista stejn\u00e9ho receptoru), ale na \u00farovni ligand-vazebn\u00e9ho proteinu nam\u00edsto \u00farovn\u011b receptoru.<\/p>\n<table style=\"width: 100%; border-collapse: collapse; margin: 16px 0;\">\n<thead>\n<tr style=\"background: #2c7cb0; color: #fff;\">\n<th style=\"padding: 10px; border: 1px solid #ddd; text-align: left;\">Krit\u00e9rium<\/th>\n<th style=\"padding: 10px; border: 1px solid #ddd; text-align: left;\">GDF-8 (Myostatin)<\/th>\n<th style=\"padding: 10px; border: 1px solid #ddd; text-align: left;\">Follistatin 344<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>Role v svalov\u00e9 biologii<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Atrofick\u00fd ligand (brzda)<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Antagonistick\u00fd vazebn\u00fd protein (odstra\u0148ova\u010d brzdy)<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>Aktivn\u00ed forma<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">109-aa homodimer (~25,8 kDa)<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">344-aa glykoproteinov\u00fd monomer (~37 kDa)<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>Receptor nebo c\u00edl<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">ActRIIB (receptor aktivinu typu IIB)<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Sekvestruje myostatin\/aktivn\u00ed (bez receptoru; p\u0159\u00edm\u00e1 vazba ligandu)<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>Downstream signalizace<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Aktivuje Smad2\/Smad3, atrogeny<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Blokuje aktivaci Smad odstran\u011bn\u00edm ligandu<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>Prim\u00e1rn\u00ed v\u00fdzkumn\u00e1 role<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">N\u00e1stroj k indukci\/zkoum\u00e1n\u00ed atrofick\u00e9ho fenotypu<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">N\u00e1stroj k reverzi\/prevenci atrofie<\/td>\n<\/tr>\n<tr style=\"background: #f9f9f9;\">\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>Typick\u00e1 v\u00fdzkumn\u00e1 d\u00e1vka<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">10\u2013100 ng\/mL in vitro; 0,1\u201310 mcg in vivo<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">10\u2013100 mcg in vivo na d\u00e1vku<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px; border: 1px solid #ddd;\"><strong>Sp\u00e1rov\u00e1n\u00ed<\/strong><\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Pou\u017e\u00edv\u00e1 se spole\u010dn\u011b s follistatinem 344 pro stanoven\u00ed vazebn\u00e9 stechiometrie<\/td>\n<td style=\"padding: 10px; border: 1px solid #ddd;\">Pou\u017e\u00edv\u00e1 se spole\u010dn\u011b s GDF-8 k ov\u011b\u0159en\u00ed antagonistick\u00e9 aktivity<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Pro v\u00fdzkum sval\u016f se tato dvojice pou\u017e\u00edv\u00e1 spole\u010dn\u011b t\u0159emi hlavn\u00edmi zp\u016fsoby: (1) m\u011b\u0159en\u00ed vazebn\u00e9 afinity (povrchov\u00e1 plasmonov\u00e1 rezonance, ELISA, izotermick\u00e1 titra\u010dn\u00ed kalorimetrie) interakce follistatin-myostatin; (2) bun\u011b\u010dn\u00e9 testy atrofie\/z\u00e1chrany, kde GDF-8 indukuje atrofii myotub\u016f a testuje se z\u00e1chrana pomoc\u00ed spole\u010dn\u00e9ho pod\u00e1n\u00ed follistatinu; a (3) in vivo validace, kde GDF-8 zesiluje fenotyp \u00fabytku svalov\u00e9 hmoty, kter\u00fd spole\u010dn\u00e1 aplikace follistatinu zm\u00edr\u0148uje. Tyto dva proteiny jsou mechanisticky komplement\u00e1rn\u00ed a z\u0159\u00eddka se studuj\u00ed izolovan\u011b.<\/p>\n<h2>Skladov\u00e1n\u00ed a rekonstituce<\/h2>\n<p><strong>P\u0159ed rekonstituci:<\/strong> lyofilizovan\u00e9 lahvi\u010dky skladujte v chladni\u010dce p\u0159i 2\u20138 \u00b0C v p\u016fvodn\u00edm obalu pro kr\u00e1tkodob\u00e9 pracovn\u00ed z\u00e1soby. Pro dlouhodob\u00e9 skladov\u00e1n\u00ed neotev\u0159en\u00fdch lahvi\u010dek zmrazte p\u0159i \u221220 \u00b0C. Lyofilizovan\u00e9 GDF-8 je stabiln\u00ed v chladni\u010dce a\u017e 12 m\u011bs\u00edc\u016f a p\u0159i \u221220 \u00b0C a\u017e 24 m\u011bs\u00edc\u016f \u2013 o n\u011bco krat\u0161\u00ed dobu ne\u017e mal\u00e9 syntetick\u00e9 peptidy, proto\u017ee v\u011bt\u0161\u00ed rekombinantn\u00ed dimer s disulfidov\u00fdmi vazbami je n\u00e1chyln\u011bj\u0161\u00ed k chybn\u00e9mu skl\u00e1d\u00e1n\u00ed a agregaci v pr\u016fb\u011bhu \u010dasu. Vyhn\u011bte se cykl\u016fm zmrazov\u00e1n\u00ed a rozmrazov\u00e1n\u00ed lyofilizovan\u00e9ho pr\u00e1\u0161ku.<\/p>\n<p><strong>Postup rekonstituce:<\/strong> Aplikujte bakteriostatickou vodu po vnit\u0159n\u00ed st\u011bn\u011b lahvi\u010dky (ne p\u0159\u00edmo na lyofilizovan\u00fd kol\u00e1\u010d). Pro 1mg lahvi\u010dku poskytuje 1,0 ml bakteriostatick\u00e9 vody pracovn\u00ed koncentraci 1 mg\\\/ml. Jemn\u011b krou\u017eiv\u011b prom\u00edchejte \u2014 do <strong>ne<\/strong> skladujte v chladni\u010dce p\u0159i 2\u20138 \u00b0C a pou\u017eijte do 30 dn\u016f pro optim\u00e1ln\u00ed stabilitu. Rekonstituovan\u00fd roztok nezmrazujte \u2013 rekombinantn\u00ed dimerick\u00e9 proteiny jsou obzvl\u00e1\u0161t\u011b citliv\u00e9 na denaturaci p\u0159i zmrazov\u00e1n\u00ed a rozmrazov\u00e1n\u00ed, co\u017e vede k agregaci a ztr\u00e1t\u011b receptorov\u00e9 vazebn\u00e9 aktivity. Zlikvidujte jakoukoli lahvi\u010dku s projevy z\u00e1kalu, sra\u017eeniny nebo zm\u011bny barvy. Pro testy vazebn\u00e9 afinity vy\u017eaduj\u00edc\u00ed p\u0159esnou kalibraci d\u00e1vka-odpov\u011b\u010f pou\u017e\u00edvejte \u010derstv\u011b rekonstituovan\u00fd roztok do 7 dn\u016f pro nejreprodukovateln\u011bj\u0161\u00ed v\u00fdsledky.<\/p>\n<p><strong>Po rekonstituci:<\/strong> Skladujte v chladni\u010dce p\u0159i teplot\u011b 2\u20138 \u00b0C a spot\u0159ebujte do 30 dn\u016f pro optim\u00e1ln\u00ed stabilitu. Rekonstituovan\u00fd roztok nezmrazujte \u2014 rekombinantn\u00ed dimern\u00ed proteiny jsou obzvl\u00e1\u0161t\u011b citliv\u00e9 na denaturaci zmrazen\u00edm a rozmrazen\u00edm, kter\u00e1 zp\u016fsobuje agregaci a ztr\u00e1tu vazebn\u00e9 aktivity na receptor. Likvidujte ka\u017edou lahvi\u010dku vykazuj\u00edc\u00ed z\u00e1kal, sra\u017eeninu nebo zm\u011bnu barvy. Pro testy vazebn\u00e9 afinity vy\u017eaduj\u00edc\u00ed p\u0159esnou kalibraci d\u00e1vkov\u00e9 odpov\u011bdi pou\u017e\u00edvejte \u010derstv\u011b rekonstituovan\u00fd roztok do 7 dn\u016f pro co nejreprodukovateln\u011bj\u0161\u00ed v\u00fdsledky.<\/p>\n<h2 id=\"faqs\">\u010casto kladen\u00e9 dotazy<\/h2>\n<h3>K \u010demu se v v\u00fdzkumu pou\u017e\u00edv\u00e1 GDF-8 (Myostatin)?<\/h3>\n<p>a f\u00fazn\u00edch protein\u016f ActRIIB-Fc) a kvantifikaci vazebn\u00e9 stechiometrie ve farmakologick\u00fdch testech. Nepou\u017e\u00edv\u00e1 se k \u201ezlep\u0161en\u00ed\u201c \u010dehokoli ve v\u00fdzkumn\u00fdch modelech \u2013 je to negativn\u00ed regul\u00e1tor, kter\u00fd cht\u011bj\u00ed v\u011bdci pochopit a nakonec inhibovat. V\u00fdzkumn\u00e9 GDF-8 prod\u00e1van\u00e9 zde je <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">Follistatin 344<\/a> a f\u00fazn\u00ed proteiny ActRIIB-Fc) a kvantifikace vazebn\u00e9 stechiometrie ve farmakologick\u00fdch testech. Nepou\u017e\u00edv\u00e1 se k \u201cvylep\u0161en\u00ed\u201d \u010dehokoli ve v\u00fdzkumn\u00fdch modelech \u2014 je to negativn\u00ed regul\u00e1tor, kter\u00e9mu cht\u011bj\u00ed v\u00fdzkumn\u00edci porozum\u011bt a nakonec jej inhibovat. Zde prod\u00e1van\u00fd GDF-8 v\u00fdzkumn\u00e9 kvality je <strong>ne<\/strong> schv\u00e1len\u00fd FDA a je dod\u00e1v\u00e1n v\u00fdhradn\u011b pro laboratorn\u00ed v\u00fdzkumn\u00e9 \u00fa\u010dely.<\/p>\n<h3>Jak se GDF-8 li\u0161\u00ed od Follistatin 344?<\/h3>\n<p>Tato dvojice p\u0159edstavuje inverzn\u00ed farmakologick\u00fd p\u00e1r. GDF-8 je aktivn\u00ed ligand myostatinu \u2014 brzda svalov\u00e9ho r\u016fstu, kter\u00e1 prost\u0159ednictv\u00edm signalizace Smad2\/Smad3 \u0159\u00edd\u00ed atrofii. Follistatin 344 je vazebn\u00fd protein s vysokou afinitou, kter\u00fd sekvestruje GDF-8 a aktivin a znemo\u017e\u0148uje jejich dostupnost pro receptor. Ve v\u00fdzkumn\u00fdch modelech GDF-8 indukuje nebo zesiluje fenotyp atrofie a follistatin 344 jej zvrac\u00ed. Oba se b\u011b\u017en\u011b kombinuj\u00ed v testech vazebn\u00e9 afinity, bun\u011b\u010dn\u00fdch z\u00e1chrann\u00fdch testech a in-vivo valida\u010dn\u00edch studi\u00edch antagonist\u016f myostatinov\u00e9 dr\u00e1hy.<\/p>\n<h3>Jak se li\u0161\u00ed GDF-8 od GDF-11?<\/h3>\n<p>GDF-8 (myostatin) a GDF-11 sd\u00edlej\u00ed p\u0159ibli\u017en\u011b 90% aminokyselinov\u00e9 identity v zral\u00e9 dom\u00e9n\u011b a v\u00e1\u017eou se na stejn\u00fd receptor ActRIIB s porovnatelnou afinitou. Funk\u010dn\u00ed role jsou \u010d\u00e1ste\u010dn\u011b p\u0159ekr\u00fdvaj\u00edc\u00ed, ale li\u0161\u00ed se v tk\u00e1\u0148ov\u00e9 distribuci: GDF-8 je p\u0159ev\u00e1\u017en\u011b exprimov\u00e1n v kostern\u00edm svalstvu a je dominantn\u00edm regul\u00e1torem svalov\u00e9 hmoty; GDF-11 je exprimov\u00e1n \u0161ir\u0161\u00edm spektrem tk\u00e1n\u00ed a je studov\u00e1n v souvislosti se srdcem, nervovou soustavou a hematopoetick\u00fdm syst\u00e9mem. T\u011bsn\u00e1 sekven\u010dn\u00ed podobnost \u010din\u00ed v\u00fdvoj selektivn\u00edch antagonist\u016f hlavn\u00edm c\u00edlem sou\u010dasn\u00e9ho v\u00fdzkumu.<\/p>\n<h3>Jak\u00e1 je typick\u00e1 v\u00fdzkumn\u00e1 d\u00e1vka GDF-8?<\/h3>\n<p>Publikovan\u00e9 preklinick\u00e9 protokoly obvykle pou\u017e\u00edvaj\u00ed pracovn\u00ed koncentrace 10\u2013100 ng\/mL pro in-vitro experimenty s bun\u011b\u010dn\u00fdmi kulturami (testy atrofie myotub, testy s report\u00e9rov\u00fdmi bu\u0148kami, studie vazby) a 0,1\u201310 mcg na pod\u00e1n\u00ed pro in-vivo protokoly indukce atrofie u hlodavc\u016f. 1 mg lahvi\u010dka rekonstituovan\u00e1 s 1,0 mL bakteriostatick\u00e9 vody poskytne koncentraci 1 mg\/mL \u2013 \u0159ed\u011bn\u00ed do PBS nebo kultiva\u010dn\u00edho m\u00e9dia vytvo\u0159\u00ed nanomol\u00e1rn\u00ed pracovn\u00ed roztoky pro in-vitro pou\u017eit\u00ed.<\/p>\n<h3>Je GDF-8 schv\u00e1len FDA?<\/h3>\n<p>Ne. GDF-8 \/ myostatin nen\u00ed schv\u00e1len FDA, EMA, MHRA ani \u017e\u00e1dn\u00fdm jin\u00fdm v\u00fdznamn\u00fdm regul\u00e1torem pro terapeutick\u00e9 pou\u017eit\u00ed u lid\u00ed. V\u00fdzkum myostatinov\u00e9 dr\u00e1hy p\u0159inesl antagonisty ve f\u00e1zi klinick\u00fdch studi\u00ed (protil\u00e1tky proti myostatinu, solubiln\u00ed ActRIIB-Fc, genov\u00e1 terapie follistatinem), z nich\u017e n\u011bkter\u00e9 dos\u00e1hly pozdn\u00edch f\u00e1z\u00ed test\u016f pro svalovou dystrofii a sarkopenii, ale rekombinantn\u00ed GDF-8 samotn\u00fd nen\u00ed terapeutikum. Ve\u0161ker\u00fd GDF-8 prod\u00e1van\u00fd dodavateli pouze pro v\u00fdzkumn\u00e9 \u00fa\u010dely je ur\u010den pro laboratorn\u00ed v\u00fdzkum a nem\u011bl by b\u00fdt pod\u00e1v\u00e1n lidem.<\/p>\n<h3>Jak by m\u011bl b\u00fdt GDF-8 skladov\u00e1n?<\/h3>\n<p>Lyofilizovan\u00e9 lahvi\u010dky: kr\u00e1tkodob\u011b skladujte p\u0159i 2\u20138 \u00b0C, dlouhodob\u011b p\u0159i \u221220 \u00b0C pro neotev\u0159en\u00e9 lahvi\u010dky. Rekonstituovan\u00fd roztok: skladujte p\u0159i 2\u20138 \u00b0C, pou\u017e\u00edvejte do 30 dn\u016f pro obecn\u00e9 protokoly nebo do 7 dn\u016f pro testy vazebn\u00e9 afinity vy\u017eaduj\u00edc\u00ed p\u0159esnou kalibraci. Rekonstituovan\u00fd roztok nezmrazujte \u2013 rekombinantn\u00ed dimerick\u00e9 proteiny jsou obzvl\u00e1\u0161t\u011b citliv\u00e9 na denaturaci p\u0159i zmrazen\u00ed a rozmrazen\u00ed. Chra\u0148te p\u0159ed p\u0159\u00edm\u00fdm sv\u011btlem za v\u0161ech okolnost\u00ed. Pro pracovn\u00ed \u0159ed\u011bn\u00ed pod 100 mcg\/mL se doporu\u010duje nosn\u00fd protein (BSA v 0,1%).<\/p>\n<h3>Jak rekonstituovat GDF-8?<\/h3>\n<p>Postupujte podle v\u00fd\u0161e uveden\u00e9ho rekonstitu\u010dn\u00edho postupu. P\u0159idejte bakteriostatickou vodu po st\u011bn\u011b lahvi\u010dky (ne p\u0159\u00edmo na lyofilizovan\u00fd pr\u00e1\u0161ek), jemn\u011b prom\u00edchejte a nechte 5\u201310 minut pro \u00fapln\u00e9 rozpu\u0161t\u011bn\u00ed. Ne <strong>ne<\/strong> prot\u0159ep\u00e1vejte lahvi\u010dku \u2013 intenzivn\u00ed m\u00edch\u00e1n\u00ed m\u016f\u017ee naru\u0161it intermolekul\u00e1rn\u00ed disulfidov\u00e9 vazby a sn\u00ed\u017eit aktivitu. Spr\u00e1vn\u011b rekonstituovan\u00fd roztok je \u010dir\u00fd a bezbarv\u00fd, bez viditeln\u00fdch \u010d\u00e1stic. Pro lahvi\u010dku 1 mg + 1,0 mL \u0159edidla je pracovn\u00ed koncentrace 1 mg\/mL.<\/p>\n<h3>Pro\u010d je specifikace \u010distoty 95% nam\u00edsto 99%?<\/h3>\n<p>Rekombinantn\u00ed proteiny jako GDF-8 nemohou dos\u00e1hnout standardu HPLC \u010distoty \u226599 %, kter\u00fd je typick\u00fd pro mal\u00e9 syntetick\u00e9 peptidy, kv\u016fli inherentn\u00ed heterogenit\u011b jak\u00e9hokoli rekombinantn\u00edho expresn\u00edho syst\u00e9mu \u2013 r\u016fzn\u00e9 intermedi\u00e1ty skl\u00e1d\u00e1n\u00ed a formy disulfidov\u00fdch izomer\u016f se na HPLC jev\u00ed jako souvisej\u00edc\u00ed p\u00edky, kter\u00e9 nejsou ne\u010distoty, ale izoformy c\u00edlov\u00e9ho proteinu. HPLC \u010distota \u226595 % je standardn\u00ed v\u00fdzkumn\u00e1 specifikace pro GDF-8 a podobn\u00e9 rekombinantn\u00ed disulfidem v\u00e1zan\u00e9 dimerick\u00e9 proteiny. SDS-PAGE typicky vykazuje o\u010dek\u00e1van\u00fd p\u00e1s ~25,8 kDa v neredukuj\u00edc\u00edch podm\u00ednk\u00e1ch a monomer ~12,9 kDa v redukuj\u00edc\u00edch podm\u00ednk\u00e1ch.<\/p>\n<h3>Jak\u00e9 s\u00edly nab\u00edz\u00ed MedsBase?<\/h3>\n<p>MedsBase nab\u00edz\u00ed rekombinantn\u00ed GDF-8 (Myostatin) v lyofilizovan\u00fdch vialk\u00e1ch po 1 mg. Vialka je dostupn\u00e1 v balen\u00ed po 10 nebo 20 vialk\u00e1ch. V\u0161echny vialky jsou dod\u00e1v\u00e1ny s HPLC \u010distotou \u226595 % a certifik\u00e1tem anal\u00fdzy dostupn\u00fdm na vy\u017e\u00e1d\u00e1n\u00ed.<\/p>\n<h3>Lze GDF-8 a Follistatin 344 kombinovat ve v\u00fdzkumu?<\/h3>\n<p>Ano \u2013 toto je kanonick\u00fd p\u0159\u00edpad pou\u017eit\u00ed. Tyto dv\u011b l\u00e1tky se b\u011b\u017en\u011b kombinuj\u00ed t\u0159emi hlavn\u00edmi zp\u016fsoby: (1) m\u011b\u0159en\u00ed vazebn\u00e9 afinity interakce follistatin-myostatin pomoc\u00ed SPR, ELISA nebo ITC; (2) bun\u011b\u010dn\u00e9 testy atrofie\/z\u00e1chrany, kde GDF-8 indukuje atrofii myotubul\u016f a spole\u010dn\u00e1 l\u00e9\u010dba follistatinem ji zachra\u0148uje; a (3) in-vivo studie, kde GDF-8 zesiluje fenotyp ch\u0159adnut\u00ed, kter\u00fd spole\u010dn\u00e1 aplikace follistatinu zm\u00edr\u0148uje. Toto p\u00e1rov\u00e1n\u00ed inverzn\u00ed farmakologie je z\u00e1kladem v\u00fdzkumn\u00e9ho designu osy myostatinu.<\/p>\n<h3>Zp\u016fsobuje GDF-8 ve v\u00fdzkumu vedlej\u0161\u00ed \u00fa\u010dinky?<\/h3>\n<p>Hlavn\u00edm c\u00edlov\u00fdm \u00fa\u010dinkem rekombinantn\u00edho GDF-8 ve v\u00fdzkumn\u00fdch modelech je svalov\u00e1 atrofie \u2013 toto je zam\u00fd\u0161len\u00fd farmakologick\u00fd \u00fa\u010dinek, nikoli vedlej\u0161\u00ed efekt. Mezi mimoc\u00edlov\u00e9 n\u00e1lezy pat\u0159\u00ed m\u00edrn\u00e9 \u00fa\u010dinky na srde\u010dn\u00ed a tukov\u00e9 tk\u00e1n\u011b, kter\u00e9 odpov\u00eddaj\u00ed ni\u017e\u0161\u00ed \u00farovni exprese ActRIIB v t\u011bchto kompartmentech. P\u0159i velmi vysok\u00fdch d\u00e1vk\u00e1ch lze pozorovat \u0161ir\u0161\u00ed \u00fa\u010dinky souvisej\u00edc\u00ed s nadrodinou TGF-\u03b2 na fibr\u00f3zu a z\u00e1n\u011bt, kter\u00e9 jsou p\u0159i\u010d\u00edt\u00e1ny zk\u0159\u00ed\u017een\u00e9 reakci receptor\u016f s drahami aktivinu a GDF-11.<\/p>\n<h3>Jak\u00fd je polo\u010das GDF-8?<\/h3>\n<p>V preklinick\u00e9m v\u00fdzkumu m\u00e1 rekombinantn\u00ed zral\u00fd GDF-8 plazmatick\u00fd polo\u010das p\u0159ibli\u017en\u011b 2\u20134 hodiny po intraven\u00f3zn\u00edm pod\u00e1n\u00ed. Endogenn\u011b cirkuluje zral\u00fd myostatin v\u00e1zan\u00fd na sv\u016fj vlastn\u00ed prodomen (latentn\u00ed komplex) a na follistatin\/ostatn\u00ed vazebn\u00e9 proteiny, co\u017e v\u00fdrazn\u011b prodlu\u017euje efektivn\u00ed tk\u00e1\u0148ov\u00fd polo\u010das. Pro v\u00fdzkumn\u00e9 protokoly je rekombinantn\u00ed aktivn\u00ed dimer pod\u00e1v\u00e1n bez prodomenu, aby dodal \u201cvoln\u00fd\u201d myostatin receptoru ActRIIB.<\/p>\n<h3>Pro\u010d byl GDF-8 p\u016fvodn\u011b objeven?<\/h3>\n<p>GDF-8 byl identifikov\u00e1n McPherronem, Lawlerem a Leem na Johns Hopkins (Nature 1997) pomoc\u00ed degenerovan\u00e9-PCR screeningov\u00e9 strategie navr\u017een\u00e9 k nalezen\u00ed nov\u00fdch \u010dlen\u016f nadrodiny TGF-\u03b2. C\u00edlen\u00e1 disrupce u my\u0161\u00ed vytvo\u0159ila zv\u00ed\u0159ata s dvakr\u00e1t a\u017e t\u0159ikr\u00e1t v\u011bt\u0161\u00ed hmotnost\u00ed kostern\u00edho svalstva ne\u017e u divok\u00fdch kontrol \u2013 n\u00e1padn\u011b jasn\u00fd fenotyp, kter\u00fd okam\u017eit\u011b stanovil myostatin jako dominantn\u00ed fyziologick\u00fd negativn\u00ed regul\u00e1tor r\u016fstu sval\u016f. Souvislost s p\u0159irozen\u011b se vyskytuj\u00edc\u00edmi fenotypy \u201cdvojit\u00e9ho svalstva\u201d u belgick\u00fdch modr\u00fdch krav a whippet\u016f byla stanovena b\u011bhem m\u011bs\u00edc\u016f a p\u0159\u00edpad lidsk\u00e9 mutace MSTN byl publikov\u00e1n v NEJM v roce 2004.<\/p>\n<h3>Jak dlouho trv\u00e1, ne\u017e se projev\u00ed \u00fa\u010dinky GDF-8 v preklinick\u00e9m v\u00fdzkumu?<\/h3>\n<p>In-vitro \u00fa\u010dinky na fosforylaci Smad2\/Smad3 jsou detekovateln\u00e9 b\u011bhem minut po expozici bun\u011bk. Atrofie myotubul\u016f v bun\u011b\u010dn\u00fdch testech je m\u011b\u0159iteln\u00e1 b\u011bhem 24\u201372 hodin. In-vivo atrofick\u00e9 fenotypy u hlodavc\u016f se vyv\u00edjej\u00ed b\u011bhem 1\u20134 t\u00fddn\u016f pravideln\u00e9ho pod\u00e1v\u00e1n\u00ed, p\u0159i\u010dem\u017e kinetika z\u00e1vis\u00ed na d\u00e1vce, zp\u016fsobu pod\u00e1n\u00ed a z\u00e1kladn\u00ed linii svalov\u00e9 hmoty modelov\u00e9ho organismu.<\/p>\n<h3>Mohu si objednat GDF-8 pro mezin\u00e1rodn\u00ed p\u0159epravu?<\/h3>\n<p>Ano. MedsBase zas\u00edl\u00e1 GDF-8 po cel\u00e9m sv\u011bt\u011b prost\u0159ednictv\u00edm na\u0161\u00ed specializovan\u00e9 s\u00edt\u011b pro p\u0159epravu peptid\u016f. Objedn\u00e1vky obsahuj\u00edc\u00ed pouze peptidy se kvalifikuj\u00ed pro na\u0161i samostatnou slu\u017ebu p\u0159epravy peptid\u016f. V\u0161echny objedn\u00e1vky jsou odes\u00edl\u00e1ny v teplotn\u011b kontrolovan\u00e9m balen\u00ed s pln\u00fdm sledov\u00e1n\u00edm a jsou pokryty na\u0161\u00edm <a href=\"https:\/\/medsbase.com\/cs\/medsbase-re-shipment-assurance-policy\/\">Z\u00e1rukou op\u011btovn\u00e9ho odesl\u00e1n\u00ed<\/a>.<\/p>\n<p><!-- medsbase-related-alts-v1 --><\/p>\n<h2>Dal\u0161\u00ed peptidy pro v\u00fdzkum anabolick\u00fdch \u00fa\u010dink\u016f, sval\u016f a r\u016fstov\u00e9 osy<\/h2>\n<ul>\n<li><a href=\"\/cs\/follistatin-344\/\"><strong>Follistatin 344<\/strong><\/a> \u2014 Myostatin \/ aktivin antagonistick\u00e1 vazebn\u00e1 b\u00edlkovina \u2014 inverzn\u011b farmakologick\u00fd p\u00e1r k GDF-8<\/li>\n<li><a href=\"\/cs\/igf-1-lr3\/\"><strong>IGF-1 LR3<\/strong><\/a> \u2014 Dlouho-argininov\u00fd rekombinantn\u00ed analog IGF-1 \u2014 anabolick\u00fd stimul opa\u010dnou cestou p\u0159es IGF-1R<\/li>\n<li><a href=\"\/cs\/tb-500\/\"><strong>TB-500 (Thymosin Beta-4)<\/strong><\/a> \u2014 Syst\u00e9mov\u00fd hojiv\u00fd fragment \u2014 v\u00fdzkum obnovy sval\u016f a srde\u010dn\u00ed tk\u00e1n\u011b<\/li>\n<li><a href=\"\/cs\/cjc-1295-with-dac\/\"><strong>CJC-1295 with DAC<\/strong><\/a> \u2014 Dlouhodob\u011b p\u016fsob\u00edc\u00ed analog GHRH \u2013 v\u00fdzkum r\u016fstov\u00e9 osy<\/li>\n<li><a href=\"\/cs\/sermorelin\/\"><strong>Sermorelin<\/strong><\/a> \u2014 Krat\u0161\u00ed p\u016fsob\u00edc\u00ed analog GHRH(1-29) \u2014 v\u00fdzkum p\u0159irozen\u00fdch pulz\u016f r\u016fstov\u00e9ho hormonu<\/li>\n<\/ul>\n<p><!-- medsbase-peptide-guide-cta --><\/p>\n<h2>Dal\u0161\u00ed \u010dten\u00ed<\/h2>\n<div style=\"background: #f4f8fb; border-left: 4px solid #2c7cb0; padding: 18px 22px; margin: 18px 0; border-radius: 4px;\">\n<p style=\"margin: 0 0 8px 0;\"><strong>\ud83d\udcd6 Prozkoumejte myostatinovou dr\u00e1hu<\/strong><\/p>\n<p style=\"margin: 0;\">Prohl\u00e9dn\u011bte si celou <a href=\"https:\/\/medsbase.com\/cs\/peptides\/\"><strong>katalog v\u00fdzkumn\u00fdch peptid\u016f<\/strong><\/a>, s inverzn\u011b farmakologick\u00fdm p\u00e1rem <a href=\"https:\/\/medsbase.com\/cs\/follistatin-344\/\">Follistatin 344<\/a> jako myostatinov\u00fd antagonista pro v\u00fdzkum z\u00e1chrany dr\u00e1hy, <a href=\"https:\/\/medsbase.com\/cs\/igf-1-lr3\/\">IGF-1 LR3<\/a> pro p\u0159\u00edm\u00fd v\u00fdzkum anabolick\u00fdch \u00fa\u010dink\u016f p\u0159es IGF-receptor, a <a href=\"https:\/\/medsbase.com\/cs\/tb-500\/\">TB-500<\/a> pro v\u00fdzkum syst\u00e9mov\u00e9 obnovy sval\u016f a tk\u00e1n\u00ed.<\/p>\n<\/div>\n<p><!-- pep-seo-v1 --><\/p>","protected":false},"excerpt":{"rendered":"<p>\u2705 Rekombinantn\u00ed aktivn\u00ed myostatinov\u00fd homodimer 25,8 kDa<br \/>\n\u2705 Kanonick\u00fd atrofick\u00fd ligand superrodiny TGF-\u03b2<br \/>\n\u2705 Inverzn\u011b farmakologick\u00fd p\u00e1r k Follistatinu 344<br \/>\n\u2705 Agonista dr\u00e1hy ActRIIB \/ Smad2\/Smad3<br \/>\n\u2705 \u226595% HPLC \u010distota, COA na vy\u017e\u00e1d\u00e1n\u00ed<\/p>\n<p><strong>GDF-8 (Myostatin)<\/strong> je rekombinantn\u00ed protein.<\/p>","protected":false},"featured_media":70950,"comment_status":"open","ping_status":"closed","template":"","meta":[],"product_brand":[],"product_cat":[5426],"product_tag":[6279,6278,5441],"class_list":{"0":"post-70729","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-peptides","7":"product_tag-gdf-8","8":"product_tag-myostatin","9":"product_tag-peptide","11":"first","12":"instock","13":"shipping-taxable","14":"purchasable","15":"product-type-variable","16":"has-default-attributes"},"acf":[],"_links":{"self":[{"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/product\/70729","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/comments?post=70729"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/media\/70950"}],"wp:attachment":[{"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/media?parent=70729"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/product_brand?post=70729"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/product_cat?post=70729"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/medsbase.com\/cs\/wp-json\/wp\/v2\/product_tag?post=70729"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}