Xu Shaoqi, Wang Mei, Li Ya, Tang Ni, Zhang Xin, Chen Hu, Zhang Shupeng, Liu Yanling, Wang Jun, Chen Defang, Li Zhiqiong
College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China.
Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River, Neijiang Normal University, Neijiang, Sichuan, People's Republic of China.
Fish Physiol Biochem. 2022 Apr;48(2):419-436. doi: 10.1007/s10695-022-01055-7. Epub 2022 Feb 20.
In 1996, kiss was reported to regulate feeding in mammals, but studies are limited in fish. Our study aimed to explore the possible role of kiss in the regulation of feeding in Siberian sturgeon (Acipenser baerii). kiss1 and kiss2 were cloned, and the expression patterns were analyzed in Siberian sturgeon. The complete coding regions of kiss1 and kiss2 genes were 393 and 471 bp. Both kiss1 and kiss2 showed the highest expression level in the hypothalamus. During the periprandial and fasting experiments, the expression of kiss1 and kiss2 highly significantly increased in the hypothalamus after feeding (P < 0.01). Compared with the feeding group, in hypothalamus, kiss1 expression in the fasting group highly significantly decreased (P < 0.01). In contrast, kiss2 expression had no significant difference on days 1 and 7 (P > 0.05) but highly significantly increased on day 14 (P < 0.01). Subsequently, the feeding function was verified by intraperitoneal (i.p.) injection of Kp1(10) and Kp1(10) into fish. The results showed that i.p. injection of 1 µg/g BW Kp1(10) or 0.01 µg/g BW Kp2(10) could significantly reduce 0-1 h food intake (P < 0.05) and affected the expression levels of apelin, ghrelin, leptin, nmu, etc. in the hypothalamus. These results suggested that kiss1 plays an anorexic role in both short- and long-term feeding regulation, while kiss2 plays a short-term anorexic and long-term orexigenic role. This study described kiss as a novel regulator of appetite in fish and laid the groundwork for further studies focused on physiological function. HIGHLIGHTS: • The kiss1 and kiss2 of Siberian sturgeon were cloned. • The expression levels of kiss1 and kiss2 mRNA were the highest in the hypothalamus. • Postprandial hypothalamic kiss1 and kiss2 expression levels increased in the periprandial experiment. • In the fasting test, the expression of hypothalamic kiss1 decreased after fasting, while the expression of kiss2 increased after fasting on the 14th day. • Siberian sturgeon food intake was reduced, and appetite factors expression levels in the hypothalamus were altered after intraperitoneal injection of Kp1(10) and Kp2(10).
1996年，有报道称亲吻素在哺乳动物的进食调节中发挥作用，但在鱼类中的研究有限。我们的研究旨在探讨亲吻素在西伯利亚鲟（Acipenser baerii）进食调节中的可能作用。克隆了kiss1和kiss2，并分析了它们在西伯利亚鲟中的表达模式。kiss1和kiss2基因的完整编码区分别为393和471 bp。kiss1和kiss2在下丘脑中均表现出最高的表达水平。在围食期和禁食实验中，进食后下丘脑中kiss1和kiss2的表达极显著增加（P < 0.01）。与进食组相比，禁食组下丘脑中kiss1的表达极显著降低（P < 0.01）。相比之下，kiss2的表达在第1天和第7天无显著差异（P > 0.05），但在第14天极显著增加（P < 0.01）。随后，通过向鱼腹腔注射Kp1(10)和Kp2(10)来验证其进食功能。结果表明，腹腔注射1 μg/g体重的Kp1(10)或0.01 μg/g体重的Kp2(10)可显著降低0 - 1小时的食物摄入量（P < 0.05），并影响下丘脑中apelin、ghrelin（胃饥饿素）、leptin（瘦素）、nmu等的表达水平。这些结果表明，kiss1在短期和长期进食调节中均发挥厌食作用，而kiss2则发挥短期厌食和长期促食欲作用。本研究将亲吻素描述为鱼类食欲的一种新型调节因子，并为进一步关注其生理功能的研究奠定了基础。
• 克隆了西伯利亚鲟的kiss1和kiss2。
• kiss1和kiss2 mRNA的表达水平在下丘脑中最高。
• 在围食期实验中，进食后下丘脑中kiss1和kiss2的表达水平升高。
• 在禁食实验中，禁食后下丘脑中kiss1的表达降低，而kiss2的表达在第14天禁食后升高。
• 腹腔注射Kp1(10)和Kp2(10)后，西伯利亚鲟的食物摄入量减少，下丘脑中食欲因子的表达水平改变。
