Programa de Doctorado en Biotecnología, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile; Universidad Andres Bello, Facultad de Ciencias de la Vida, Departamento de Ciencias Biológicas, 8370146 Santiago, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), 4030000 Concepción, Chile.
Universidad Andres Bello, Facultad de Ciencias de la Vida, Departamento de Ciencias Biológicas, 8370146 Santiago, Chile.
Comp Biochem Physiol A Mol Integr Physiol. 2024 Dec;298:111746. doi: 10.1016/j.cbpa.2024.111746. Epub 2024 Sep 18.
Cortisol hormone is considered the main corticosteroid in fish stress, acting through glucocorticoid (GR) or mineralocorticoid (MR) receptor. The 11-deoxycorticosterone (DOC) corticosteroid is also secreted during stress and could complement the cortisol effects, but this still not fully understood. Hence, we evaluated the early transcriptomic response of rainbow trout (Oncorhynchus mykiss) liver by DOC through GR or MR. Thirty juvenile trout were pretreated with an inhibitor of endogenous cortisol synthesis (metyrapone) by intraperitoneal injection in presence or absence of GR (mifepristone) and MR (eplerenone) pharmacological antagonists for one hour. Then, fish were treated with a physiological DOC dose or vehicle (DMSO-PBS1X as control) for three hours (n = 5 per group). We measured several metabolic parameters in plasma, together with the liver glycogen content. Additionally, we constructed cDNA libraries from liver of each group, sequenced by HiseqX Illumina technology and then analyzed by RNA-seq. Plasma pyruvate and cholesterol levels decreased in DOC-administered fish and only reversed by eplerenone. Meanwhile, DOC increased liver glycogen contents depending on both corticosteroid receptor pathways. RNA-seq analysis revealed differential expressed transcripts induced by DOC through GR (448) and MR (1901). The enriched biological processes to both were mainly related to stress response, protein metabolism, innate immune response and carbohydrates metabolism. Finally, we selected sixteen genes from enriched biological process for qPCR validation, presenting a high Pearson correlation (0.8734 average). These results describe novel physiological effects of DOC related to early metabolic and transcriptomic responses in fish liver and differentially modulated by MR and GR.
皮质醇激素被认为是鱼类应激反应中的主要皮质类固醇，通过糖皮质激素（GR）或盐皮质激素（MR）受体发挥作用。11-脱氧皮质酮（DOC）皮质类固醇也在应激时分泌，可能补充皮质醇的作用，但这仍不完全清楚。因此，我们通过 GR 或 MR 评估了 DOC 对虹鳟（Oncorhynchus mykiss）肝脏的早期转录组应答。30 条幼鱼通过腹腔注射内源性皮质醇合成抑制剂（米托坦）预处理 1 小时，存在或不存在 GR（米非司酮）和 MR（依普利酮）药理学拮抗剂。然后，用生理剂量的 DOC 或载体（DMSO-PBS1X 作为对照）处理鱼 3 小时（每组 n=5）。我们测量了血浆中的几种代谢参数，以及肝糖原含量。此外，我们从每组肝脏构建 cDNA 文库，通过 HiseqX Illumina 技术进行测序，然后通过 RNA-seq 进行分析。DOC 给药的鱼血浆丙酮酸和胆固醇水平降低，仅被依普利酮逆转。同时，DOC 通过两种皮质类固醇受体途径增加肝脏糖原含量。RNA-seq 分析显示，DOC 通过 GR（448）和 MR（1901）诱导的差异表达转录物。这两种途径富集的生物学过程主要与应激反应、蛋白质代谢、先天免疫反应和碳水化合物代谢有关。最后，我们从富集的生物过程中选择了 16 个基因进行 qPCR 验证，呈现出高 Pearson 相关性（平均 0.8734）。这些结果描述了 DOC 与鱼类肝脏早期代谢和转录组应答相关的新的生理作用，并通过 MR 和 GR 差异调节。
