Helmling Steffen, Maasch Christian, Eulberg Dirk, Buchner Klaus, Schröder Werner, Lange Christian, Vonhoff Stefan, Wlotzka Britta, Tschöp Matthias H, Rosewicz Stefan, Klussmann Sven
NOXXON Pharma AG, Max Dohrn-Strasse 8-10, 10589 Berlin, Germany.
Proc Natl Acad Sci U S A. 2004 Sep 7;101(36):13174-9. doi: 10.1073/pnas.0404175101. Epub 2004 Aug 25.
Employing in vitro selection techniques, we have generated biostable RNA-based compounds, so-called Spiegelmers, that specifically bind n-octanoyl ghrelin, the recently discovered endogenous ligand for the type 1a growth hormone secretagogue (GHS) receptor. Ghrelin is a potent stimulant of growth hormone release, food intake, and adiposity. We demonstrate that our lead compound, L-NOX-B11, binds ghrelin with low-nanomolar affinity and inhibits ghrelin-mediated GHS-receptor activation in cell culture with an IC(50) of 5 nM. l-NOX-B11 is highly specific for the bioactive, n-octanoylated form of ghrelin. Like the GHS receptor, it does not recognize the inactive unmodified peptide and requires only the N-terminal five amino acids for the interaction. The i.v. administration of polyethylene glycol modified l-NOX-B11 efficiently suppresses ghrelin-induced growth hormone release in rats. These results demonstrate that the neutralization of circulating bioactive ghrelin leads to inhibition of ghrelin's secretory effects in the CNS.
利用体外筛选技术，我们生成了生物稳定的基于RNA的化合物，即所谓的镜像分子，它们能特异性结合正辛酰胃饥饿素，这是最近发现的1a型生长激素促分泌素（GHS）受体的内源性配体。胃饥饿素是生长激素释放、食物摄入和肥胖的有效刺激物。我们证明，我们的先导化合物L-NOX-B11以低纳摩尔亲和力结合胃饥饿素，并在细胞培养中抑制胃饥饿素介导的GHS受体激活，IC50为5 nM。L-NOX-B11对生物活性的正辛酰化形式的胃饥饿素具有高度特异性。与GHS受体一样，它不识别无活性的未修饰肽，相互作用仅需要N端的五个氨基酸。静脉注射聚乙二醇修饰的L-NOX-B11可有效抑制大鼠体内胃饥饿素诱导的生长激素释放。这些结果表明，循环生物活性胃饥饿素的中和导致中枢神经系统中胃饥饿素分泌作用的抑制。
