Yan Xiao, Qin Chaobin, Yang Guokun, Deng Dapeng, Yang Liping, Feng Junchang, Mi Jiali, Nie Guoxing
College of Fisheries, Henan Normal University, Xinxiang 453007, China.
Animals (Basel). 2020 Nov 20;10(11):2163. doi: 10.3390/ani10112163.
Apelin, a kind of active polypeptide, has many biological functions, such as promoting food intake, enhancing immunity, and regulating energy balance. In mammals, studies have indicated that apelin is involved in regulating food intake. However, there are relatively few studies about the regulatory effect of apelin on fish feeding, and the specific mechanism is not clear. Therefore, the purpose of this study was to preliminarily investigate the regulatory effects of apelin on key genes of feeding and growth in common carp ( L.) through in vitro and in vivo experiments. In the present study, after incubation with different concentrations of Pyr-apelin-13 (0, 10, 100, and 1000 nM) in hypothalamic fragments, the expressions of () and () mRNA were significantly up-regulated at 12 and 3 h, respectively, and the significant down-regulation of () mRNA expression was observed at 1 and 3 h. In vivo, after Pyr-apelin-13 oral administration (0, 1, 10, and 100 pmol/g), the mRNA level in the hypothalamus of common carp was significantly increased at 1, 6, and 12 h, while () mRNA levels in the hypothalamus of common carp were significantly down-regulated. Following incubation with different concentrations of Pyr-apelin-13 (0, 10, 100, and 1000 nM) in primary hepatocytes, (), (), (), and () mRNA levels were significantly increased at 3 h. In vivo, the levels of (), , (), and mRNA were significantly increased after the oral administration of Pyr-apelin-13 in the hepatopancreas, in a time and dose-dependent manner. These results support the hypothesis that Pyr-apelin-13 might regulate the feeding and growth of common carp through mediating the expressions of appetite- and growth-related genes. Overall, apelin, which is an orexigenic peptide, improves food intake and is involved in the growth of common carp.
Apelin是一种活性多肽，具有多种生物学功能，如促进摄食、增强免疫力和调节能量平衡。在哺乳动物中，研究表明Apelin参与调节食物摄入。然而，关于Apelin对鱼类摄食的调节作用的研究相对较少，具体机制尚不清楚。因此，本研究的目的是通过体外和体内实验初步探究Apelin对鲤鱼（L.）摄食和生长关键基因的调节作用。在本研究中，下丘脑片段与不同浓度的Pyr-apelin-13（0、10、100和1000 nM）孵育后， （）和 （）mRNA的表达分别在12小时和3小时显著上调，而在1小时和3小时观察到 （）mRNA表达显著下调。在体内，口服Pyr-apelin-13（0、1、10和100 pmol/g）后，鲤鱼下丘脑的 mRNA水平在1、6和12小时显著升高，而鲤鱼下丘脑的（） mRNA水平显著下调。原代肝细胞与不同浓度的Pyr-apelin-13（0、10、100和1000 nM）孵育后， （）、 （）、 （）和 （）mRNA水平在3小时显著升高。在体内，口服Pyr-apelin-13后，肝胰脏中 （）、 、 （）和 mRNA水平显著升高，呈时间和剂量依赖性。这些结果支持了Pyr-apelin-13可能通过介导食欲和生长相关基因的表达来调节鲤鱼摄食和生长的假说。总体而言，Apelin作为一种促食欲肽，可改善食物摄入并参与鲤鱼的生长。
