人源PCSK9^(D374Y)加重蛋氨酸胆碱缺乏饮食诱导的小鼠非酒精性脂肪性肝炎  

Human PCSK9^(D374Y)exacerbates methionine choline deficiency diet-induced nonalcoholic steatohepatitis in mice

作　　者：阿比旦·阿卜杜如苏力 陈小翠 崔元峰 托罗娜依·米吉提 邓李惠 陈邦党 Abidan·ABUDURUSULI;CHEN Xiaocui;CUI Yuanfeng;Tuoluonayi·MIJITI;DENG Lihui;CHEN Bangdang(School of Basic Medical Sciences,Xinjiang Medical University,Urumqi 830000;Clinical Medical Research Institute,the First Affiliated Hospital of Xinjiang Medical University,Urumqi 830000,China)

机构地区：[1]新疆医科大学基础医学院,新疆乌鲁木齐830000 [2]新疆医科大学第一附属医院临床医学研究院,新疆乌鲁木齐830000

出　　处：《基础医学与临床》2025年第5期637-643,共7页Basic and Clinical Medicine

基　　金：新疆维吾尔自治区自然科学基金重点项目(2022D01D16);国家自然科学基金-新疆联合基金本地青年人才培养专项(U1903304)。

摘　　要：目的探讨人源前蛋白转化酶枯草杆菌素/Kexin 9型(PCSK9)基因功能获得性突变(hPCSK9^(D374Y))对蛋氨酸胆碱缺乏饮食(MCD)诱导的小鼠非酒精性脂肪性肝炎(NASH)的影响。方法选用16只C57BL/6J野生型小鼠,随机分为hPCSK9^(D374Y)组与对照GFP组,MCD喂养6周,检测肝脏三酰甘油含量及血清丙氨酸氨基转移酶(ALT)和天冬氨酸氨基转移酶(AST)水平。通过油红O及天狼星红染色评估肝脏脂质浸润及纤维化程度;免疫组化分析F4/80阳性细胞浸润情况。Western blot检测脂质合成及炎性反应相关蛋白,RT-qPCR分析相关mRNA表达。结果hPCSK9^(D374Y)组小鼠肝脏hPCSK9蛋白及mRNA显著上调,LDLR蛋白表达下调,血清ALT与AST水平显著升高(P<0.05)。肝脏脂肪变性和纤维化程度加重,F4/80阳性细胞显著增多(P<0.01)。Western blot分析显示hPCSK9^(D374Y)组FASN和SCD1蛋白显著上调,PPARα下调;TLR4和p-P65表达升高,而IκBα表达降低(P<0.001)。RT-qPCR结果表明炎性因子TNF-α、IL-1β、IL-6和MCP-1的mRNA水平显著增加,纤维化相关mRNA(collagen Ⅰ α和collagen Ⅲ α)显著上调(P<0.001)。结论人源PCSK9基因功能获得性突变(hPCSK9^(D374Y))加重了MCD诱导的小鼠肝脏脂肪变性、炎性反应和纤维化。Objective To investigate the effect of mutation human proprotein convertase subtilism/kexin type 9(hPCSK9^(D374Y))in PCSK9 gene on methionine choline deficiency diet(MCD)-induced nonalcoholic steato-hepatitis(NASH)in mice.Methods Sixteen C57BL/6J wild-type mice were selected and randomly divided into the hPCSK9^(D374Y)group and the control GFP group.MCD was fed for 6 weeks,and then the serum level of hepatic triglyceride,alanine aminotransferase(ALT)and aspartate aminotransferase(AST)was examined.Oil Red O and Sirius Red staining microscopy were used to identify hepatic lipid infiltration and fibrosis severity.F4/80-positive cell infiltration was analyzed using immunohistochemistry.Lipid synthesis and inflammatory response-related proteins were detected by Western blot and related mRNA expression was analyzed by RT-qPCR.Results Hepatic hPCSK9 protein and mRNA were significantly up-regulated,LDLR protein expression was down-regulated,and serum level of ALT and AST was significantly elevated in the hPCSK9^(D374Y)group of mice(P<0.05).The degree of hepatic steatosis and fibrosis increased and F4/80-positive cells were significantly increased(P<0.01).FASN and SCD1 proteins were significantly up-regulated and PPARαwas down-regulated in the hPCSK9^(D374Y)group;The expression of TLR4 and p-P65 was elevated,whereas the expression of IκBαwas decreased(P<0.001).RT-qPCR results showed a significant increase of mRNA coding inflammatory factors TNF-α,IL-1β,IL-6,and MCP-1,and a significant up-regulation of fibrosis-associated mRNAs(collagen Ⅰ α and collagen Ⅲ α)was found(P<0.001).Conclusions Functionally acquired mutation in the PCSK9 gene(hPCSK9^(D374Y))exacerbates MCD-induced hepatic steatosis,inflammatory response and fibrosis in mice.

关 键 词：非酒精性脂肪性肝炎 前蛋白转化酶枯草溶菌素9(PCSK9) 蛋氨酸胆碱缺乏饮食(MCD) 炎性因子 

分 类 号：R575.5[医药卫生—消化系统]