Departament of Physiology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Departament of Physiology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Gen Comp Endocrinol. 2021 Feb 1;302:113661. doi: 10.1016/j.ygcen.2020.113661. Epub 2020 Nov 19.
To test the hypothesis of conservation of stanniocalcin 1 and 2 (STC-1; STC-2) metabolic functions in vertebrates, we performed an in vitro study to determine if these hormones are implicated in regulation of the gluconeogenesis pathway, glycogen synthesis, and C-glucose conversion to CO in livers from fed and fasting rats (Rattus norvegicus). Stc1 and Stc2 gene expressions increased in the liver after fasting. STC-1 participated in the regulation of the hepatic gluconeogenesis pathway in rats when the precursor was C-lactate. STC-2 demonstrated variational signaling on rat hepatic gluconeogenesis activity and Pck1 gene expression, decreasing levels in the fed state when the substrate was C-alanine and increasing levels during fasting when the substrate was C-lactate. At the concentrations used in this study, STC-1 and STC-2 did not affect glycogen concentration and synthesis from C-glucose or C-glucose conversion to CO in the livers from fed or fasting rats. These findings highlight the role of stanniocalcins in the hepatic gluconeogenesis pathway in mammals and confirm the conservation of STC-1 and STC-2 metabolic functions in the vertebrates.
为了检验硬骨鱼钙结合蛋白 1 和 2(STC-1;STC-2)在代谢功能上在脊椎动物中保守的假说,我们进行了一项体外研究,以确定这些激素是否参与了调节糖异生途径、糖原合成以及 C-葡萄糖向肝脏中 CO 的转化,所用动物为禁食和正常进食的大鼠(Rattus norvegicus)。禁食后大鼠肝脏中的 Stc1 和 Stc2 基因表达增加。当前体为 C-乳酸时,STC-1 参与了大鼠肝脏糖异生途径的调节。STC-2 对大鼠肝脏糖异生活性和 Pck1 基因表达表现出不同的信号,当底物为 C-丙氨酸时,在进食状态下降低水平,而当底物为 C-乳酸时,在禁食状态下增加水平。在本研究中使用的浓度下,STC-1 和 STC-2 不影响来自 C-葡萄糖的肝糖原浓度和合成,也不影响 C-葡萄糖向 CO 的转化,无论是在正常进食的大鼠还是禁食的大鼠的肝脏中都是如此。这些发现强调了硬骨鱼钙结合蛋白在哺乳动物肝脏糖异生途径中的作用,并证实了 STC-1 和 STC-2 在脊椎动物中的代谢功能的保守性。