Yang Guokun, Liang Xiaomin, Jiang Yanle, Li Chengquan, Zhang Yanmin, Zhang Xindang, Chang Xulu, Shen Yawei, Meng Xiaolin
College of Fisheries, Henan Normal University, Xinxiang 453007, China.
Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang 453007, China.
Aquac Nutr. 2022 Nov 7;2022:4330251. doi: 10.1155/2022/4330251. eCollection 2022.
GIP plays an important regulatory role in glucose and lipid metabolism. As the specific receptor, GIPR is involved in this physiological process. To assess the roles of GIPR in teleost, the GIPR gene was cloned from grass carp. The ORF of cloned GIPR gene was 1560 bp, encoding 519 amino acids. The grass carp GIPR was the G-protein-coupled receptor which contains seven predicted transmembrane domains. In addition, two predicted glycosylation sites were contained in the grass carp GIPR. The grass carp GIPR expression is in multiple tissues and is highly expressed in the kidney, brain regions, and visceral fat tissue. In the OGTT experiment, the GIPR expression is markedly decreased in the kidney, visceral fat, and brain by treatment with glucose for 1 and 3 h. In the fast and refeeding experiment, the GIPR expression in the kidney and visceral fat tissue was significantly induced in the fast groups. In addition, the GIPR expression levels were markedly decreased in the refeeding groups. In the present study, the visceral fat accumulation of grass carp was induced by overfed. The GIPR expression was significantly decreased in the brain, kidney, and visceral fat tissue of overfed grass carp. In primary hepatocytes, the GIPR expression was promoted by treatment with oleic acid and insulin. The GIPR mRNA levels were significantly reduced by treatment with glucose and glucagon in the grass carp primary hepatocytes. To our knowledge, this is the first time the biological role of GIPR is unveiled in teleost.
胃抑制多肽（GIP）在葡萄糖和脂质代谢中发挥着重要的调节作用。作为特异性受体，GIP受体（GIPR）参与了这一生理过程。为了评估GIPR在硬骨鱼中的作用，从草鱼中克隆了GIPR基因。克隆的GIPR基因的开放阅读框（ORF）为1560 bp，编码519个氨基酸。草鱼GIPR是一种G蛋白偶联受体，含有7个预测的跨膜结构域。此外，草鱼GIPR中含有两个预测的糖基化位点。草鱼GIPR在多个组织中表达，在肾脏、脑区和内脏脂肪组织中高表达。在口服葡萄糖耐量试验（OGTT）中，用葡萄糖处理1小时和3小时后，肾脏、内脏脂肪和脑中的GIPR表达明显降低。在禁食和再投喂实验中，禁食组肾脏和内脏脂肪组织中的GIPR表达显著诱导。此外，再投喂组中的GIPR表达水平明显降低。在本研究中，过度投喂诱导了草鱼内脏脂肪的积累。过度投喂的草鱼脑、肾和内脏脂肪组织中的GIPR表达显著降低。在原代肝细胞中，油酸和胰岛素处理可促进GIPR表达。在草鱼原代肝细胞中，葡萄糖和胰高血糖素处理可显著降低GIPR mRNA水平。据我们所知，这是首次在硬骨鱼中揭示GIPR的生物学作用。
