AIM: To investigate the underlying mechanism of ghrelin-induced gastro-protection in a cell culture model of ethanol-induced gastric epithelial cell injury. METHODS: The human gastric epithelial cell line GES-1 was incubated with ghrelin (0.01-1 µM), 1 µM ghrelin and 1 µM D-Lys3-growth hormone releasing peptide-6 (GHRP-6), or 1 µM ghrelin and 400 nM antagomiR-21 for 24 h, followed by treatment with 8% ethanol for 3 h to induce apoptosis. Cell viability was determined by MTT assays and flow cytometry was used for detection of apoptosis rates. miR-21 transcription was analyzed by qRT-PCR and Akt, Bcl-2, Bax and caspase 3 expressions were measured by Western blot. RESULTS: Flow cytometry and a quantitative RT-PCR analysis of the expression of miR-21 showed that ghrelin inhibited apoptosis in a dose dependent manner through a signaling pathway that was both growth hormone secretagogue receptor (GHS-R) and miR-21 dependent, as the antiapoptotic effect of ghrelin was blocked by both D-Lys3-GHRP-6 and antagomiR-21, respectively. Western blotting of Akt, Bcl-2, Bax, and caspase 3 showed that the levels of the antiapoptotic proteins, Akt and Bcl-2, in the cells pretreated with ghrelin alone were higher than those in the cells pretreated with D-Lys3-GHRP-6 or antagomiR-21. By contrast, the levels of the proapoptotic proteins, Bax and caspase 3, in the cells pretreated with ghrelin alone were lower than those in the cells pretreated with D-Lys3-GHRP-6 or antagomiR-21. CONCLUSION: Ghrelin inhibits GES-1 cell apoptosis through GHS-R-dependent signaling in which miR-21 activates the PI3K/Akt pathway, which upregulates Bcl-2 and downregulates Bax and caspase 3 expression.
AIM: To investigate the underlying mechanism of ghrelin-induced gastro-protection in a cell culture model of ethanol-induced gastric epithelial cell injury. METHODS: The human gastric epithelial cell line GES-1 was incubated with ghrelin (0.01-1 µM), 1 µM ghrelin and 1 µM D-Lys3-growth hormone releasing peptide-6 (GHRP-6), or 1 µM ghrelin and 400 nM antagomiR-21 for 24 h, followed by treatment with 8% ethanol for 3 h to induce apoptosis. Cell viability was determined by MTT assays and flow cytometry was used for detection of apoptosis rates. miR-21 transcription was analyzed by qRT-PCR and Akt, Bcl-2, Bax and caspase 3 expressions were measured by Western blot. RESULTS: Flow cytometry and a quantitative RT-PCR analysis of the expression of miR-21 showed that ghrelin inhibited apoptosis in a dose dependent manner through a signaling pathway that was both growth hormone secretagogue receptor (GHS-R) and miR-21 dependent, as the antiapoptotic effect of ghrelin was blocked by both D-Lys3-GHRP-6 and antagomiR-21, respectively. Western blotting of Akt, Bcl-2, Bax, and caspase 3 showed that the levels of the antiapoptotic proteins, Akt and Bcl-2, in the cells pretreated with ghrelin alone were higher than those in the cells pretreated with D-Lys3-GHRP-6 or antagomiR-21. By contrast, the levels of the proapoptotic proteins, Bax and caspase 3, in the cells pretreated with ghrelin alone were lower than those in the cells pretreated with D-Lys3-GHRP-6 or antagomiR-21. CONCLUSION:Ghrelin inhibits GES-1 cell apoptosis through GHS-R-dependent signaling in which miR-21 activates the PI3K/Akt pathway, which upregulates Bcl-2 and downregulates Bax and caspase 3 expression.
Authors: V Sibilia; G Rindi; F Pagani; D Rapetti; V Locatelli; A Torsello; N Campanini; R Deghenghi; C Netti Journal: Endocrinology Date: 2003-01 Impact factor: 4.736
Authors: H Ariyasu; K Takaya; T Tagami; Y Ogawa; K Hosoda; T Akamizu; M Suda; T Koh; K Natsui; S Toyooka; G Shirakami; T Usui; A Shimatsu; K Doi; H Hosoda; M Kojima; K Kangawa; K Nakao Journal: J Clin Endocrinol Metab Date: 2001-10 Impact factor: 5.958
Authors: Alexander Marson; Stuart S Levine; Megan F Cole; Garrett M Frampton; Tobias Brambrink; Sarah Johnstone; Matthew G Guenther; Wendy K Johnston; Marius Wernig; Jamie Newman; J Mauro Calabrese; Lucas M Dennis; Thomas L Volkert; Sumeet Gupta; Jennifer Love; Nancy Hannett; Phillip A Sharp; David P Bartel; Rudolf Jaenisch; Richard A Young Journal: Cell Date: 2008-08-08 Impact factor: 41.582
Authors: T Brzozowski; P C Konturek; S J Konturek; S Kwiecień; D Drozdowicz; W Bielanski; R Pajdo; A Ptak; A Nikiforuk; W W Pawlik; E G Hahn Journal: Regul Pept Date: 2004-08-15
Authors: Sharmilee Gnanapavan; Blerina Kola; Stephen A Bustin; Damian G Morris; Patrick McGee; Peter Fairclough; Satya Bhattacharya; Robert Carpenter; Ashley B Grossman; Márta Korbonits Journal: J Clin Endocrinol Metab Date: 2002-06 Impact factor: 5.958