Effects of Recombinant Leptin Proteins on the Expression of Key Genes in the HPG Axis and Liver of Tongue Sole In Vitro
Xin Cai,
Yaxing Zhang,
Bin Wang,
Aijun Cui,
Yan Jiang,
Zhaojun Meng,
Yuting Li,
Yongjiang Xu
Affiliations
Xin Cai
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Yaxing Zhang
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Bin Wang
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Aijun Cui
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Yan Jiang
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Zhaojun Meng
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Yuting Li
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Yongjiang Xu
State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
Leptin (Lep) plays a crucial role in controlling food intake and maintaining energy balance in mammals. While several studies have shown the presence of multiple leptin genes in teleosts, limited information is currently available on how sex steroid hormones regulate the expression of these genes in fish. In this study, we used two previously expressed and purified leptin proteins to incubate four tissues in vitro (hypothalamic-pituitary-gonadal axis and liver) and used the RT-qPCR method to detect the expression of genes related to growth and reproduction in tongue sole (Cynoglossus semilaevis). The results showed that both recombinant LepA and LepB proteins of tongue sole almost entirely suppressed the expression of genes related to growth and reproduction in the hypothalamic-pituitary-gonadal axis and liver, while LepB may have had a positive role on steroid synthesis in gonads. Further, a high concentration of LepA facilitated the expression of IGF-Ι in liver. At the same time, we utilized human leptin to incubate four tissues in vitro; although most of them had trends similar to those stimulated with tongue sole leptins, there were still some differences, indicating differences among leptin homologs between humans and fishes. To our knowledge, this is the first study to explore the function of tongue sole LepA and LepB within the hypothalamic-pituitary-gonadal axis and liver in vitro. Our results provide a valuable resource and foundation for future studies.
