Yeh Matthew M, Shi Xiuhui, Yang Jingxuan, Li Min, Fung Kar-Ming, Daoud Sayed S
Department of Laboratory Medicine and Pathology, University of Washington, School of Medicine, Seattle, Washington, USA.
Department of Medicine and Department of Surgery, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
Hepatol Res. 2022 May;52(5):433-448. doi: 10.1111/hepr.13754. Epub 2022 Feb 16.
The prevalence of non-alcoholic fatty liver disease (NAFLD) and its progression to non-alcoholic steatohepatitis (NASH) is higher in postmenopausal women than men. The aim of this study was to determine the molecular mechanisms underlying this sexual dimorphism in NAFLD.
A total of 24 frozen liver samples of both sexes (normal and NAFLD/NASH) were used in this study. Total RNAseq was first used to identify differentially expressed genes (DEGs) between samples. Enrichment analysis of Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome were used to analyze biological pathways. RT profiler polymerase chain reaction (PCR) arrays were used to identify genes associated with the biological pathways. Immunoblotting was used to validate protein expression of certain genes.
We identified 4362 genes that are differentially expressed between NAFLD/NASH and normal samples; of those 745 genes were characterized as sex specific in NAFLD/NASH. Multiple pathway analysis platforms showed that Wnt-signaling is a candidate shared for a common biological pathway-associated with NAFLD/NASH. Using Wnt pathway focused PCR array we identified many genes involved in canonical pathway (Wnt/β-catenin activation) such as CTNNB1, c-Myc and CCND2 are overexpressed in female cases, whereas these genes are either not detected or downregulated in male cases. Immunoblot analysis validated the expression of CTNNB1 in female cases but not in male protein samples.
Our study suggests, for the first time, that the activation of canonical Wnt signaling could be one of the main pathways associated with sexual dimorphism in NAFLD and NASH.
绝经后女性非酒精性脂肪性肝病（NAFLD）的患病率及其进展为非酒精性脂肪性肝炎（NASH）的情况高于男性。本研究的目的是确定NAFLD中这种性别差异背后的分子机制。
本研究共使用了24份男女两性的冷冻肝脏样本（正常样本和NAFLD/NASH样本）。首先使用全RNA测序来鉴定样本之间的差异表达基因（DEG）。基因本体论（GO）、京都基因与基因组百科全书（KEGG）和Reactome的富集分析用于分析生物学途径。RT Profiler聚合酶链反应（PCR）阵列用于鉴定与生物学途径相关的基因。免疫印迹用于验证某些基因的蛋白表达。
我们鉴定出4362个在NAFLD/NASH样本和正常样本之间差异表达的基因；其中745个基因在NAFLD/NASH中具有性别特异性。多个途径分析平台表明，Wnt信号通路是与NAFLD/NASH相关的共同生物学途径的候选共享通路。使用聚焦Wnt途径的PCR阵列，我们鉴定出许多参与经典途径（Wnt/β-连环蛋白激活）的基因，如CTNNB1、c-Myc和CCND2在女性病例中过表达，而在男性病例中这些基因要么未被检测到，要么表达下调。免疫印迹分析验证了CTNNB1在女性病例中的表达，但在男性蛋白样本中未验证。
我们的研究首次表明，经典Wnt信号通路的激活可能是与NAFLD和NASH中的性别差异相关的主要途径之一。
