Jacek Owczarek, Piotr Szcześniak, Daria Orszulak-Michalak
Wykorzystanie greliny w chorobach układu sercowo-naczyniowego
oraz niektórych chorobach nowotworowych
Use of ghrelin in therapy of some cardiovascular and neoplastic diseases. Ghrelin has several cardiovascular activities, including a cardioprotective effects against myocardial ischemia and vasoactive and cardiotropic effects in humans. These effects are mediated by the interactions of these ligands with binding sites, including GHS-1Ra, for which the signaling pathways are not documented fully. Identification of the cardiac and vascular binding sites for ghrelin and synthetic, growth hormone releasing peptides will provide new perspectives for treating cardiovascular diseases with these ligands. Ghrelin also exerts influence on cardiovascular system. In vitro studies revealed that ghrelin, as well as des-acyl ghrelin, can inhibit apoptosis of cardiomyocytes and endothelial cells. In healthy volunteers, intravenous ghrelin administration resulted in cardiac afterload reduction due to decrease in mean arterial pressure. Furthermore ghrelin increased cardiac output, with no change in heart rate. Besides its modulatory role in GH secretion, feeding and blood pressure ghrelin could also influence the growth of neoplastic cells. Moreover, ghrelin expression might also depend on the size and the stage of cancer development. Therefore, it has been hypothesized that ghrelin could play a role in the mechanisms underlying development of some tumors throught autocrine and/or paracrine pathway.