Przygrodzka Emilia, Binderwala Fatema, Powers Robert, McFee Renee M, Cupp Andrea S, Wood Jennifer R, Davis John S
bioRxiv. 2024 Feb 14:2024.02.14.580329. doi: 10.1101/2024.02.14.580329.
Progesterone production by the corpus luteum is fundamental for establishing and maintaining pregnancy. The pituitary gonadotropin luteinizing hormone (LH) is recognized as the primary stimulus for luteal formation and progesterone synthesis, regardless of species. Previous studies demonstrated an elevation in abundance of genes related to glucose and lipid metabolism during the follicular to luteal transition. However, the metabolic phenotype of these highly steroidogenic cells has not been studied. Herein, we determined acute metabolic changes induced by LH in primary luteal cells and defined pathways required for progesterone synthesis. Untargeted metabolomics analysis revealed that LH induces rapid changes in vital metabolic pathways, including glycolysis, tricarboxylic acid (TCA) cycle, pentose phosphate pathway, lipogenesis, and hydrolysis of phospholipids. LH stimulated glucose uptake, enhanced glycolysis, and flux of [U- C ]-labeled glucose-derived carbons into metabolic branches associated with adenosine 5'-triphosphate (ATP) and NADH/NADPH production, synthesis of nucleotides, proteins, and lipids, glycosylation of proteins or lipids, and redox homeostasis. Selective use of small molecule inhibitors targeting the most significantly changed pathways, such as glycolysis, TCA cycle, and lipogenesis, uncovered cellular metabolic routes required for LH-stimulated steroidogenesis. Furthermore, LH via the protein kinase A (PKA) pathway triggered translational modification of acetyl-CoA carboxylase alpha (ACACA) and ATP citrate lyase (ACLY), enzymes involved in synthesis of fatty acids. Inhibition of ACLY and fatty acid transport into mitochondria reduced LH-stimulated ATP, cAMP production, PKA activation, and progesterone synthesis. Taken together, these findings reveal novel hormone-sensitive metabolic pathways essential for maintaining LHCGR/PKA signaling and steroidogenesis in ovarian luteal cells.
The establishment and maintenance of pregnancy require a well-developed corpus luteum, an endocrine gland within the ovary that produces progesterone. Although there is increased awareness of intracellular signaling events initiating the massive production of progesterone during the reproductive cycle and pregnancy, there are critical gaps in our knowledge of the metabolic and lipidomic pathways required for initiating and maintaining luteal progesterone synthesis. Here, we describe rapid, hormonally triggered metabolic pathways, and define metabolic targets crucial for progesterone synthesis by ovarian steroidogenic cells. Understanding hormonal control of metabolic pathways may help elucidate approaches for improving ovarian function and successful reproduction or identifying metabolic targets for developing nonhormonal contraceptives.
黄体产生孕酮对于建立和维持妊娠至关重要。无论物种如何，垂体促性腺激素黄体生成素（LH）被认为是黄体形成和孕酮合成的主要刺激因素。先前的研究表明，在卵泡向黄体转变过程中，与葡萄糖和脂质代谢相关的基因丰度升高。然而，这些高度类固醇生成细胞的代谢表型尚未得到研究。在此，我们确定了LH在原代黄体细胞中诱导的急性代谢变化，并确定了孕酮合成所需的途径。非靶向代谢组学分析表明，LH诱导了重要代谢途径的快速变化，包括糖酵解、三羧酸（TCA）循环、磷酸戊糖途径、脂肪生成和磷脂水解。LH刺激葡萄糖摄取，增强糖酵解，并使[U-¹³C]-标记的葡萄糖衍生碳流入与三磷酸腺苷（ATP）和NADH/NADPH产生、核苷酸、蛋白质和脂质合成、蛋白质或脂质糖基化以及氧化还原稳态相关的代谢分支。选择性使用针对变化最显著的途径（如糖酵解、TCA循环和脂肪生成）的小分子抑制剂，揭示了LH刺激的类固醇生成所需的细胞代谢途径。此外，LH通过蛋白激酶A（PKA）途径触发了参与脂肪酸合成的乙酰辅酶A羧化酶α（ACACA）和ATP柠檬酸裂解酶（ACLY）的翻译后修饰。抑制ACLY和脂肪酸向线粒体的转运降低了LH刺激的ATP、cAMP产生、PKA激活和孕酮合成。综上所述，这些发现揭示了维持卵巢黄体细胞中LHCGR/PKA信号传导和类固醇生成所必需的新型激素敏感代谢途径。
妊娠的建立和维持需要一个发育良好的黄体，它是卵巢内产生孕酮的内分泌腺。尽管人们越来越意识到在生殖周期和妊娠期间启动大量孕酮产生的细胞内信号事件，但我们对启动和维持黄体孕酮合成所需的代谢和脂质组学途径的了解仍存在关键空白。在此，我们描述了快速的、激素触发的代谢途径，并确定了卵巢类固醇生成细胞孕酮合成至关重要的代谢靶点。了解激素对代谢途径的控制可能有助于阐明改善卵巢功能和成功繁殖的方法，或确定开发非激素避孕药的代谢靶点。
