Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, USA; Drug & Disease Discovery D3 Research Center, University of Kentucky College of Medicine, Lexington, KY, USA.
Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, and Central Arkansas Veterans Affairs Healthcare System, Little Rock, AR 72205, USA.
Prostaglandins Other Lipid Mediat. 2024 Aug;173:106840. doi: 10.1016/j.prostaglandins.2024.106840. Epub 2024 Jun 1.
We have previously demonstrated that the glucocorticoid receptor β (GRβ) isoform induces hepatic steatosis in mice fed a normal chow diet. The GRβ isoform inhibits the glucocorticoid-binding isoform GRα, reducing responsiveness and inducing glucocorticoid resistance. We hypothesized that GRβ regulates lipids that cause metabolic dysfunction. To determine the effect of GRβ on hepatic lipid classes and molecular species, we overexpressed GRβ (GRβ-Ad) and vector (Vec-Ad) using adenovirus delivery, as we previously described. We fed the mice a normal chow diet for 5 days and harvested the livers. We utilized liquid chromatography-mass spectrometry (LC-MS) analyses of the livers to determine the lipid species driven by GRβ. The most significant changes in the lipidome were monoacylglycerides and cholesterol esters. There was also increased gene expression in the GRβ-Ad mice for lipogenesis, eicosanoid synthesis, and inflammatory pathways. These indicate that GRβ-induced glucocorticoid resistance may drive hepatic fat accumulation, providing new therapeutic advantages.
我们之前已经证明,糖皮质激素受体β(GRβ)同工型在给予正常饲料的小鼠中诱导肝脂肪变性。GRβ同工型抑制糖皮质激素结合同工型 GRα,降低反应性并诱导糖皮质激素抵抗。我们假设 GRβ 调节导致代谢功能障碍的脂质。为了确定 GRβ 对肝脂质类和分子种类的影响,我们使用腺病毒传递如前所述过表达 GRβ(GRβ-Ad)和载体(Vec-Ad)。我们用正常饲料喂养小鼠 5 天,然后采集肝脏。我们利用肝脏的液相色谱-质谱(LC-MS)分析来确定 GRβ 驱动的脂质种类。脂质组中最显著的变化是单酰甘油和胆固醇酯。GRβ-Ad 小鼠的脂肪生成、类二十烷酸合成和炎症途径的基因表达也增加。这表明 GRβ 诱导的糖皮质激素抵抗可能导致肝脂肪堆积,提供新的治疗优势。