Laboratory of Molecular and Cellular Endocrinology, Division of Endocrinology, Department of Internal Medicine, University of Turin, Turin, Italy.
Peptides. 2011 Nov;32(11):2323-32. doi: 10.1016/j.peptides.2011.10.024. Epub 2011 Oct 30.
Acylated ghrelin (AG) is a 28 amino acid gastric peptide a natural ligand for the growth hormone secretagogue (GHS) receptor type 1a (GHS-R1a), endowed with GH-secreting and orexigenic properties. Besides, ghrelin exerts several peripheral metabolic actions, including modulation of glucose homeostasis and stimulation of adipogenesis. Notably, AG administration causes hyperglycemia in rodents as in humans. Ghrelin pleiotropy is supported by a widespread expression of the ghrelin gene, of GHS-R1a and other unknown ghrelin binding sites. The existence of alternative receptors for AG, of several natural ligands for GHS-R1a and of acylation-independent ghrelin non-neuroendocrine activities, suggests that there might be a complex 'ghrelin system' not yet completely explored. Moreover, the patho-physiological implications of unacylated ghrelin (UAG), and obestatin (Ob), the other two ghrelin gene-derived peptides, need to be clarified. Within the next few years, we may better understand the 'ghrelin system', where we might envisage clinical applications.
酰化 ghrelin (AG) 是一种 28 个氨基酸的胃肽，是生长激素促分泌素 (GHS) 受体 1a (GHS-R1a) 的天然配体，具有促 GH 分泌和摄食作用。此外，ghrelin 还具有多种外周代谢作用，包括调节葡萄糖稳态和刺激脂肪生成。值得注意的是，AG 给药会导致啮齿动物和人类的高血糖。ghrelin 的多效性是由广泛表达的 ghrelin 基因、GHS-R1a 和其他未知的 ghrelin 结合位点支持的。AG 的替代受体、几种 GHS-R1a 的天然配体以及非神经内分泌活性的酰化非依赖性 ghrelin 的存在表明，可能存在一个尚未完全探索的复杂“ghrelin 系统”。此外，还需要阐明未酰化 ghrelin (UAG) 和 obestatin (Ob) 的病理生理学意义，这是另外两种 ghrelin 基因衍生肽。在未来几年内，我们可能会更好地了解“ghrelin 系统”，并可能在该系统中设想临床应用。
