Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84103, Israel.
Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, 04103 Leipzig, Germany.
Cells. 2022 Sep 29;11(19):3046. doi: 10.3390/cells11193046.
Up-regulated expression of transcription-factor E2F1 in human visceral adipose tissue (VAT) characterizes a dysmetabolic obesity sub-phenotype. An E2F1-miRNA network has been described in multiple cancers. Here we investigated whether elevated VAT-E2F1 in obesity is associated with VAT-miRNA alterations similar to, or distinct from, those described in cancer. Furthermore, we assessed if E2F1-associated miRNA changes may contribute to the link between high- VAT-E2F1 and a dysmetabolic obesity phenotype. We assembled a cohort of patients with obesity and high-VAT-E2F1, matched by age, sex, ±BMI to patients with low-VAT-E2F1, with and without obesity (8 patients/groupX3 groups). We performed Nanostring©-based miRNA profiling of VAT samples from all 24 patients. Candidate E2F1-related miRNAs were validated by qPCR in an independent cohort of patients with extreme obesity, with or without type-2-diabetes (T2DM) (n = 20). Bioinformatic tools and manipulation of E2F1 expression in cells were used to establish the plausibility of the functional VAT-E2F1-miRNA network in obesity. Among n = 798 identified miRNAs, 17 were differentially expressed in relation to E2F1 and not to obesity itself. No evidence for the cancer-related E2F1-miRNA network was identified in human VAT in obesity. In HEK293-cells, overexpression/downregulation of E2F1 correspondingly altered the expression of miRNA-206 and miRNA-210-5p, two miRNAs with reported metabolic functions consistent with those of E2F1. In VAT from both cohorts, the expression of both miRNA-206 and 210-5p intercorrelated, and correlated with the expression of E2F1. In cohort 1 we did not detect significant associations with biochemical parameters. In cohort 2 of patients with extreme obesity, all those with high VAT-E2F1 showed a diabetes-complicated obesity phenotype and higher expression of miRNA-206 and miRNA-210-5p, which also correlated with fasting glucose levels (both miRNAs) and fasting insulin (miRNA-210-5p). Whilst the previously described cancer-related E2F1-miRNA network does not appear to operate in VAT in obesity, miRNAs-206 and 210-5p may link high-E2F1 expression in VAT with diabetes-complicated extreme obesity phenotype.
转录因子 E2F1 在人类内脏脂肪组织(VAT)中的表达上调是一种代谢失调性肥胖亚表型的特征。E2F1- miRNA 网络已在多种癌症中被描述。在这里,我们研究了肥胖症中升高的 VAT-E2F1 是否与 VAT-miRNA 的改变有关,这些改变与癌症中描述的改变相似或不同。此外,我们评估了 E2F1 相关的 miRNA 变化是否可能导致高-VAT-E2F1 与代谢失调性肥胖表型之间的联系。
我们组建了一个由肥胖症和高-VAT-E2F1 患者组成的队列,这些患者按年龄、性别、±BMI 与低-VAT-E2F1 患者相匹配,这些患者也有肥胖症(每组 8 例×3 组)。我们对所有 24 名患者的 VAT 样本进行了基于 Nanostring©的 miRNA 谱分析。在有或没有 2 型糖尿病(T2DM)的极端肥胖症患者的独立队列中,通过 qPCR 验证了候选 E2F1 相关 miRNA(n = 20)。生物信息学工具和细胞中 E2F1 表达的操作用于建立肥胖症中功能性 VAT-E2F1-miRNA 网络的合理性。
在鉴定的 n = 798 个 miRNA 中,有 17 个 miRNA 与 E2F1 相关,而与肥胖无关。在肥胖症患者的 VAT 中,没有发现与癌症相关的 E2F1-miRNA 网络的证据。在 HEK293 细胞中,E2F1 的过表达/下调相应地改变了 miRNA-206 和 miRNA-210-5p 的表达,这两种 miRNA 具有与 E2F1 一致的代谢功能。在两个队列的 VAT 中,miRNA-206 和 210-5p 的表达相互关联,并且与 E2F1 的表达相关。在队列 1 中,我们没有发现与生化参数有显著相关性。在队列 2 的极端肥胖症患者中,所有高 VAT-E2F1 的患者都表现出糖尿病合并肥胖症的表型,并且 miRNA-206 和 miRNA-210-5p 的表达更高,这两种 miRNA 也与空腹血糖水平(两者)和空腹胰岛素(miRNA-210-5p)相关。
虽然先前描述的癌症相关的 E2F1-miRNA 网络似乎不在肥胖症患者的 VAT 中发挥作用,但 miRNA-206 和 210-5p 可能将 VAT 中的高-E2F1 表达与糖尿病合并的极端肥胖症表型联系起来。