非酒精性脂肪性肝炎的治疗新尝试——脂蛋白脂酶激动剂

A new attempt with lipoprotein lipase agonists in the treatment of nonalcoholic steatohepatitis

目的通过生物信息学方法分析非酒精性脂肪性肝炎(NASH)相关差异表达基因(DEGs),寻找NASH发生的关键通路及潜在的治疗靶点。方法从公共基因芯片数据库下载GSE61260芯片,包含24例NASH和38例健康对照者肝组织穿刺样本芯片数据。利用R语言中的limma软件包以差异倍数>1.5且adj.P<0.05为条件筛选DEGs,clusterProfiler软件包进行GO分析和KEGG分析,STRING在线数据库进行蛋白质-蛋白质相互作用分析,L1000和DrugBank数据库进行药物预测。结果与健康对照组相比,NASH组共筛选出857个DEGs,其中上调基因167个,下调基因690个。GO分析结果显示DEGs主要参与炎症、胆固醇代谢等过程,KEGG分析结果显示DEGs主要富集于过氧化物酶体增殖物激活受体(PPAR)、非酒精性脂肪性肝病、氧化磷酸化等信号通路。其中,ACSL4、CYP7A1、FABP4、FABP5、脂蛋白酯酶(LPL)、ME1、OLR1、PLIN18个基因富集在PPAR信号通路上,与47个DEGs编码的蛋白共形成165个相互作用节点。LPL与21个DEGs存在相互作用,其表达上调具有改善脂质代谢、胰岛素抵抗及抗炎的作用。通过L1000和DrugBank数据库筛选出吉非罗齐、苯扎贝特、ω-3羧酸、甘草酸4种药物具有激活脂蛋白脂酶的作用。目前这4种药物在临床上主要用于治疗高甘油三酯血症或改善炎症。推测这4种药物在原有药理作用的基础上,可通过激活脂蛋白酯酶来促进肝脏脂质代谢、减轻炎症反应,达到改善NASH的目的。结论PPAR信号通路与NASH的发生与发展密切相关,脂蛋白脂酶激动剂治疗NASH是一种新的尝试。

Objective To analyze non-alcoholic steatohepatitis (NASH)-related differentially expressed genes (DEGs) by bioinformatics methods to find key pathways and potential therapeutic targets for NASH. Methods GSE61260 chip was downloaded from the public microarray database and liver biopsy samples from 24 NASH cases and 38 healthy controls were included. The Limma software package in R language was used to screen DEGs under the condition of difference multiple > 1.5 and adj. P < 0.05. The clusterProfiler software package was used for GO analysis and KEGG analysis. The STRING online database was used for protein-protein interaction analysis, and the L1000 and DrugBank databases were used for drug prediction. Results Compared with healthy control group, 857 DEGs were screened out in NASH group including 167 up-regulated genes and 690 down-regulated genes. GO analysis showed that DEGs were mainly involved in inflammation and cholesterol metabolism. KEGG analysis showed that DEGs were mainly enriched in PPAR, non-alcoholic fatty liver disease, oxidative phosphorylation and other signaling pathways. Among them, eight genes of ACSL4, CYP7A1, FABP4, FABP5, lipoprotein lipase, ME1, OLR1 and PLIN1 were enriched in PPAR signaling pathway, and 165 interaction nodes were formed with 47 DEGs-encoded proteins. Lipoprotein lipase interacted with 21 DEGs, and its up-regulated expression had improved lipid metabolism, insulin resistance and anti-inflammatory effects. Four drugs (gemfibrozil, bezafibrate, omega-3 carboxylic acid and glycyrrhizic acid) were screened by L1000 and DrugBank to activate lipoprotein lipase. Presently, these four drugs are clinically used to treat hypertriglyceridemia or to improve inflammation. In this regard, we speculated that the pharmacological effects of these four drugs had improved NASH by activating lipoprotein lipase to promote liver lipid metabolism and alleviate inflammation. Conclusion PPAR signaling pathway is closely associated to the occurrence and development of NASH, and thereby lipoprotein lipase agonist is a new attempt to treat NASH.