A study of the effect of ghrelin on hypothalamic agouti-related protein expressing by using GT1-7 cell lines

doi:10.3969/j.issn.1006-7795.2022.06.017

Abstract

Abstract: Objective To establish a cell line that responds to ghrelin, and to observe the effect of ghrelin induced AgRP gene expression. Methods Western blotting was used to determine the growth hormone secretagogue receptor (GHSR) expression in GT1-7 cell line. And real-time quantitative polymerase chain reaction (RT-qPCR) was carried out to determine the AgRP gene expression upon serum starving or upon ghrelin treatment in dose and time dependent manner with serum.The measurement data were expressed as mean±standard error (x±SE) independent samples t-test was used for comparison between two groups, and ANOVA (least significant difference method) was used for two-way comparison if the overall variance of data among three or four groups is equal. Results Western blotting data revealed that GT1-7 cell line expressed GHSR protein.Furthermore, serum-starvation significantly increased AgRP mRNA (P<0.001).3 hours of ghrelin treatment increased the expression of AgRP mRNA in a non-serum-starvation experiment compared with control (P=0.002) and 1 hour of ghrelin treatment (P=0.008).Additionally, while 10 nmol/L and 50 nmol/L ghrelin increased AgPP mRNA expression in a similar attitude, the 100 nmol/L of ghrelin shown even further induction of AgPP mRNA expression in non-serum-starvation experiments in GT1-7 cell lines. Conclusion Taken together, our data identified that the hypothalamic GT1-7 cell line that responds to serum-starvation and ghrelin stimulation in a time-and dose-dependent manner in terms of AgRP mRNA expression.Thus, GT1-7 cell can be used as an in vitro model to study the regulation of AgRP by hypothalamic neurons, as well as the regulation of other metabolic functions by hypothalamic neurons, especially the molecular mechanisms behind them.

Key words: ghrelin, receptors, ghrelin, agouti-related protein, arcuate nucleus of hypothalamus

CLC Number:

Li Peixin, Rao Zhijian, Huang Hu. A study of the effect of ghrelin on hypothalamic agouti-related protein expressing by using GT1-7 cell lines[J]. Journal of Capital Medical University, 0, (): 924-930.

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