Analysis of the different characteristics between omental preadipocytes and differentiated white adipocytes using bioinformatics methods

Obesity is emerging as an epidemiological issue, being associated with the onset and progress of various metabolism-related disorders. Obesity is characterized by the white adipose expansion, which encounters white adipocyte hypertrophy and hyperplasia. White adipocyte hyperplasia is defined as adipogenesis with the increase in the number of the white adipocytes from the preadipocytes. Adipogenesis contributes to distributing excess triglycerides among the smaller newly formed adipocytes, reducing the number of hypertrophic adipocytes and secreting anti-inflammatory factor. Therefore, adipogenesis is emerging as a new therapeutic target for the treatment of obesity. In the present study, for a better understanding of the contribution of the alteration of the omental differentiated white adipocytes to the systemic metabolic disorders, we downloaded the mRNA expression profiles from GEO database GSE1657, 328 differentially expressed genes (DEGs) were screened between the undifferentiated preadipocytes (UNDIF) and omental differentiated white adipocytes (DIF). The contributions of the upregulated and downregulated DEGs to the system were performed via the Gene Ontology (GO) analysis, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and Protein–Protein Interaction (PPI) network, respectively. The potential contribution of the whole altered genes in the differentiated white adipocytes was explored with the performance of Gene Set Enrichment Analysis (GSEA), especially on the GO analysis, KEGG analysis, hallmark analysis, oncogenic analysis and related miRNA analysis. The output of the current study will shed light on the new targets for the treatment of obesity and obesity-related disorders.

肥胖正逐渐成为一项公共流行病学问题，与多种代谢相关疾病的发生与进展密切相关。肥胖以白色脂肪组织扩张为特征，伴随白色脂肪细胞肥大与增生。白色脂肪细胞增生指的是从前脂肪细胞分化生成白色脂肪细胞，进而导致细胞数量增加的脂肪生成过程。脂肪生成可将过量甘油三酯分配至新生的小型脂肪细胞中，减少肥大脂肪细胞的数量，并分泌抗炎因子。因此，脂肪生成正逐渐成为治疗肥胖的新型治疗靶点。本研究为深入探究网膜来源的分化型白色脂肪细胞的表达改变对全身代谢紊乱的影响，从基因表达综合数据库（Gene Expression Omnibus，GEO）下载了数据集GSE1657的mRNA表达谱，并在未分化前脂肪细胞（UNDIF）与网膜分化型白色脂肪细胞（DIF）之间筛选得到328个差异表达基因（differentially expressed genes, DEGs）。分别通过基因本体（Gene Ontology, GO）分析、京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes, KEGG）通路分析以及蛋白质-蛋白质相互作用（Protein–Protein Interaction, PPI）网络分析，对上调与下调差异表达基因的生物学效应进行探究。此外，本研究通过基因集富集分析（Gene Set Enrichment Analysis, GSEA），包括GO分析、KEGG分析、特征基因集分析、致癌特征分析以及相关微小RNA（miRNA）分析，全面探究分化型白色脂肪细胞中全部差异表达基因的潜在作用。本研究的结果将为肥胖及肥胖相关代谢疾病的治疗提供新型靶点思路。