Inhibition of ghrelin action in vitro and in vivo by an RNA-Spiegelmer
Inhibition of ghrelin action in vitro and in vivo by an RNA-Spiegelmer
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DOI：
10.1073/pnas.0404175101
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发表时间：
2004-09-07
影响因子：
11.1
通讯作者：
Klussmann, S
中科院分区：
文献类型：
--
作者：
Helmling, S;Maasch, C;Klussmann, S
采用体外选择技术，我们已经产生了生物稳定的基于RNA的化合物，所谓的Spiegelmers，其特异性结合正辛酰生长激素释放肽，最近发现的内源性配体的类型la生长激素促分泌素（GHS）受体。生长激素释放肽是一种有效的刺激生长激素释放，食物摄入和肥胖。我们证明了我们的先导化合物L-NOX-B11以低纳摩尔亲和力结合ghrelin，并以5 nM的IC 50抑制细胞培养物中ghrelin介导的GHS受体活化。L-NOX-B11对生长素释放肽的生物活性、正辛酰化形式具有高度特异性。与GHS受体一样，它不识别无活性的未修饰肽，仅需要N末端的五个氨基酸进行相互作用。静脉注射聚乙二醇修饰的L-NOX-B11可有效抑制大鼠生长激素释放肽诱导的生长激素释放。这些结果表明，循环生物活性生长素释放肽的中和导致生长素释放肽在CNS中的分泌作用的抑制。
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 la 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 IC50 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.