mircoRNA122与肝脏疾病之间关系的研究现状

microRNA是近年来的研究热点。microRNA-122(miR-122)高表达于肝脏,其与肝脏疾病的关系日益受到人们的关注。miR-122在基因表达调控中的作用能影响肝脏疾病的进展,通过抑制或者增强miR-122的活性,可改善肝脏功能。此文就miR-122与非酒精性脂肪性肝病、丙型病毒性肝炎、肝细胞癌、急性肝衰竭等肝脏疾病的关系作如下综述。     

肝脏特异性基因miR-122与肝脏疾病研究进展

作为肝脏特异性基因miRNA之一的miR-122,其与肝脏生理及病理过程有密切联系。它不仅可促进肝细胞分化,还可调控脂类代谢。对肝脏疾病,miR-122可通过慢性丙型肝炎病毒（HCV）基因5＇-UTR结合序列相互作用来促进HCV病毒复制,反之,亦可通过miR-122-cylin G1/p53-HBV调控路径抑制慢性乙型肝炎病毒（HBV）表达及复制过程。另外,miR-122可抑制肝细胞增殖过程及其恶性转化。值得注意的是,用于HCV慢性感染治疗的首个miR-122靶向药物已研究中。随着miR-122调控慢性肝炎、肝癌作用机制及影响肝功能发挥的研究逐渐被人们所认知,在慢性感染性疾病及肿瘤治疗中,其已成为一个重要且有效治疗途径。     

循环中的microRNA-122可作为肝损伤的潜在生物学标记物

背景:肝脏特异的microRNA-122参与丙型肝炎病毒复制,并且经评估它可作为潜在抗病毒干预的指标。然而,尚没有有关循环中的miR-122在评估肝脏功能方面应用的报道。目前,关于血清学miRNA水平改变的评价最早出现在百草枯引起的急性肝中毒患者。方法:收集的血清标本使用实时反转录PCR分析。结果:显示血清miR-122和临床肝功指标丙氨酸转移酶存在正相关。此外,血清miR-122被用来评估乙型肝炎与肝细胞肝癌,发现在这两个紧密相关的疾病中,血清miR-122有明显的区别。除血清miR-122外,另一小细胞核RNA U6在肝细胞肝癌患者被抑制,表明了其在这一疾病中的预后价值。结论:总之,这些证据表明血清miR-122可以为不同的肝脏疾病提供标记物,更重要的是表明一个核酸标志物的组合,可被作为识别紧密相关疾病的一个敏感和特异的指标。     

血清microRNA-122在肝细胞癌中的预后价值与共存的临床和实验室因素相关

【据《World J Gastroenterol》2020年1月报道】题:血清microRNA-122在肝细胞癌中的预后价值与共存的临床和实验室因素相关(作者Franck M等)当前学界正在寻找新的非侵入性生物标志物,试图借此加强对肝细胞癌(HCC)患者的管理。众多亚太地区的研究表明,在乙型肝炎病毒和丙型肝炎病毒诱导的HCC患者中,肝特异性microRNA-122(miR-122)在肝组织中以及血清中的表达具有特异性。本研究旨在评估miR-122在欧洲人群HCC患者中的预后价值,并确定可能与HCC患者血清中miR-122改变有关的潜在因素。     

miR-122在D-氨基半乳糖联合脂多糖诱导急性肝衰竭小鼠体内的表达及其意义

目的 通过监测急性肝功能衰竭小鼠体内miR-122的表达,探讨miR-122与小鼠急性肝衰竭疾病程度和进展之间的关系,为肝功能衰竭的早期诊断提供新的生物学标志物. 方法将BALB/C小鼠随机分为4组,实验组用D-氨基半乳糖(D-GalN,900 mg/kg)联合脂多糖(LPS,10 μg/kg)腹腔注射建立肝衰竭模型,对照组3组,分别予以D-GalN(900 mg/kg),LPS(10 μg/kg)和等渗盐水腹腔注射,在不同时间点观察小鼠病死率、肝脏组织学变化,给药后0、1、3、5、7、9 h分别留取血清、肝脏组织标本,实时定量逆转录多聚酶链反应检测小鼠体内miRNA-122和炎症因子的表达,LNA(锁核酸)-Northern blot验证miRNA-122的表达,生化分析仪检测血清中ALT、AST水平,酶联免疫吸附法检测血清中炎症因子水平.组间均数比较用two-WayANOVA方差分析,相关性分析采用Pearson和Spearman相关分析.结果 D-GalN/LPS给药24 h,小鼠病死率率达80%以上,而3个对照组则无一只小鼠死亡;肝脏特异性miR-122在正常小鼠肝脏内含量丰富(ct≈14),D-GalN/LPS诱导后1 h,miR-122即发生了明显的变化(P=0.013),表现为上调,之后随疾病的进展,miR-122表达进行性下降,9 h下调最为明显(ct≈15,P=0.002);ALT/AST于给药1 h无明显变化,3 h后呈明显上升趋势,7 h达高峰,之后ALT/AST急剧下降;对miR-122和ALT的表达对比,发现在该模型中miR-122比ALT变化快,且持久;肝衰竭相关炎症因子肿瘤坏死因子(TNF)α和白细胞介素(IL)-6在肝组织和血清中的变化一致,均上调(P<0.05); miR-122和ALT、TNFα和IL-6的相关性分析显示miR-122与以上三项指标均呈良好的相关性(相关系数分别为-0.505、0.493和0.674、).结论 肝衰竭小鼠体内肝脏特异性miR-122和ALT呈负相关关系,但又较ALT更敏感,更持久地反映肝细胞损伤程度,且miR-122表达变化与肝脏炎症损伤相关因素TNF α、IL-6均具良好的相关性,推测miR-122有望成为判断急性肝衰竭肝细胞损伤程度的一个新的分子生物学标志物.     

非酒精性脂肪性肝病患者血清中循环microRNAs表达水平及意义

目的研究microRNAs(miRNAs)在非酒精性脂肪性肝病(NAFLD)患者血清中的表达水平和意义。方法选择NAFLD患者78例(NAFLD组)和非NAFLD人群58例(对照组)。采集入组人群血清,提取总RNA,应用qRT-PCR方法对血清中miR-21、miR34a、miR-122及miR-451表达水平进行检测;分析miRNAs血清表达水平与脂肪变性程度之间的关系。结果两组人群血清中miR-145(P=3.290)和miR21(P=1.570)表达水平无显著变化;miR-451(P=0.0309)、miRNA-122(P=0.0083)和miR-34a(P=0.0032)表达水平显著升高。NAFLD组患者根据肝脏脂肪变性程度分为轻度(46例)和重度(32例),miRNA-122(P=0.0062)和miRNA-34a(P=0.0044)的表达水平随脂肪变性程度的增加而显著升高。结论 NAFLD患者较健康人群血清miR-21、miR-34a、miR-122及miR-451表达水平升高,特别是miR-34a和miR-122可以作为NAFLD诊断的一个生物学标志分子。     

miR-122在非酒精性肝脏疾病中的作用

正microRNA122(miR-122)是肝脏中一种复杂的特异性microRNA,调节肝脏的多种生理病理过程。miRNAs是长度约为22个核苷酸大小的短的功能性非编码RNA分子,是肝细胞基因网络和通路的调节器,在肝脏疾病的进展中发挥着中心作用~([1])。这种肝脏富集转录因子调控的miRNA能够促进肝细胞的分化并调节脂质代谢,并且在作为抑制肝细胞增殖和恶性转化的抑制因子方面具有显著的活性。大多数miRNAs通过促进或抑制靶基因的翻译来发挥负向调节的作用,少数有促进转录后翻译的作用。miRNA经常发生转录后修饰,这对miR-122 3'端在调节miRNA稳定性方面非常重要。     

MicroRNA-27a通过靶向HBx mRNA抑制HBV复制

目的 探究微小RNA-27a(microRNA-27a,miR-27a)在HBV感染中的作用及分子机制.方法 实时定量PCR(quantitative real-time PCR,qRT-PCR)方法检测miR-27a对HBV DNA和HBV RNA的影响.ELISA法检测miR-27a对HBeAg和HBsAg的影响....     

肝硬化患者血清miR-122的表达及与Child-Pugh分级的关系

目的探讨肝硬化患者血清MicroRNA(miR)-122的表达水平与肝硬化Child-Pugh分级及并发症的关系。方法肝硬化患者87例,采用PCR实时荧光定量法测定患者血清miR-122水平,根据Child-Pugh分级对肝硬化患者进行分级,分析血清miR-122与肝硬化分级的关系。结果并发肝硬化腹水、消化道出血、自发性细菌性腹膜炎及失代偿期患者血清miR-122表达水平均高于未发生患者(P<0.05);不同肝硬化Child-Pugh分级血清中miR-122水平有统计学差异(P<0.05),A级与B级肝硬化患者血清miR-122水平无显著差异(P>0.05),A级和B级患者水平均显著低于C级(P<0.05)。多变量线性相关性显示,血清miR-122与丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、γ-谷氨酰转移酶(GGT)、碱性磷酸酶(ALP)呈正相关(P<0.05);与国际标准化比值(INR)及肌酐(Cr)水平呈负相关(P<0.05)。结论血清miR-122水平上升提示肝硬化已经失代偿,并与腹水、消化道出血、肝肾衰竭有关。因此,血清miR-122可作为评价肝硬化患者肝脏功能及预后的潜在生物学指标。     

辅助性T淋巴细胞17/调节性T淋巴细胞比值失衡在HBV相关肝脏疾病进展中的作用

慢性乙型肝炎患者肝脏损害多发生在免疫介导作用下,考虑病毒感染和免疫反应的相互作用是疾病病情进展的重要原因。慢性乙型肝炎可发展至肝纤维化、肝硬化甚至肝细胞癌。回顾了辅助性T淋巴细胞17(Th17)与调节性T淋巴细胞(Treg)的发现起源,叙述了二者自身特性,同时阐述了在维持免疫系统稳定过程中二者所起的作用及作用机制;详细分析了细胞失衡在慢性乙型肝炎、肝纤维化、肝硬化、肝细胞癌等各个阶段中的作用,指出Th17/Treg失衡会促使HBV相关肝脏疾病病情加重。     

miRNAs as Potential Biomarkers for Viral Hepatitis B and C

Around 257 million people are living with hepatitis B virus (HBV) chronic infection and 71 million with hepatitis C virus (HCV) chronic infection. Both HBV and HCV infections can lead to liver complications such as cirrhosis and hepatocellular carcinoma (HCC). To take care of these chronically infected patients, one strategy is to diagnose the early stage of fibrosis in order to treat them as soon as possible to decrease the risk of HCC development. microRNAs (or miRNAs) are small non-coding RNAs which regulate many cellular processes in metazoans. Their expressions were frequently modulated by up- or down-regulation during fibrosis progression. In the serum of patients with HBV chronic infection (CHB), miR-122 and miR-185 expressions are increased, while miR-29, -143, -21 and miR-223 expressions are decreased during fibrosis progression. In the serum of patients with HCV chronic infection (CHC), miR-143 and miR-223 expressions are increased, while miR-122 expression is decreased during fibrosis progression. This review aims to summarize current knowledge of principal miRNAs modulation involved in fibrosis progression during chronic hepatitis B/C infections. Furthermore, we also discuss the potential use of miRNAs as non-invasive biomarkers to diagnose fibrosis with the intention of prioritizing patients with advanced fibrosis for treatment and surveillance.     

MiR-122 in hepatitis B virus and hepatitis C virus dual infection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the most common causes of chronic liver diseases and hepatocelluar carcinomas. Over the past few years, the liver-enriched microRNA-122 (miR-122) has been shown to differentially regulate viral replication of HBV and HCV. It is notable that the level of miR-122 is positively and negatively regulated by HCV and HBV, respectively. Consistent with the well-documented phenomenon that miR-122 promotes HCV accumulation, inhibition of miR-122 has been shown as an effective therapy for the treatment of HCV infection in both chimpanzees and humans. On the other hand, miR-122 is also known to block HBV replication, and HBV has recently been shown to inhibit miR-122 expression; such a reciprocal inhibition between miR-122 and HBV suggests an intriguing possibility that miR-122 replacement may represent a potential therapy for treatment of HBV infection. As HBV and HCV have shared transmission routes, dual infection is not an uncommon scenario, which is associated with more advanced liver disease than either HBV or HCV mono-infection. Thus, there is a clear need to further understand the interaction between HBV and HCV and to delineate the role of miR-122 in HBV/HCV dual infection in order to devise effective therapy. This review summarizes the current understanding of HBV/HCV dual infection, focusing on the pathobiological role and therapeutic potential of miR-122.     

Targeting microRNA-122 to Treat Hepatitis C Virus Infection

An important host factor for hepatitis C virus (HCV) is microRNA-122 (miR-122). miR-122 is a liver-specific member of a family of small, non-coding RNA molecules known as microRNAs that play major roles in the regulation of gene expression by direct interaction with RNA targets. miR-122 binds directly to two sites in the 5' untranslated region (UTR) of HCV RNA and positively regulates the viral life cycle. The mechanism by which this regulation occurs is still not fully understood. There has been a great deal of interest in potential therapeutics based on small RNAs, and targeting miR-122 to combat HCV is one of the furthest advanced. Chemical inhibitors of miR-122 can be introduced into mammals intravenously and result in potent and specific knockdown of the microRNA, with no detectable adverse effects on liver physiology. This strategy was recently applied to chimpanzees chronically infected with HCV and resulted in a sustained reduction in viral load in the animals. Inhibition of miR-122 therefore presents a very attractive novel approach to treating HCV, a virus for which improved therapeutics are urgently needed.     

Quantification of circulating miR-125b-5p predicts survival in chronic hepatitis B patients with acute-on-chronic liver failure

Aims

To analyze the role of serum miR-125b-5p in reflecting liver damage and predicting outcomes in chronic hepatitis B (CHB) patients with acute-on-chronic liver failure (ACLF).

Serum levels of miRNA in patients with hepatitis B virus-associated acute-on-chronic liver failure

Background: Hepatitis B virus(HBV)-associated acute-on-chronic liver failure(HBV-ACLF) is a lifethreatening condition and its exact pathophysiology and progression remain unclear. The present study aimed to assess the role of serum mi RNAs in the evaluation of HBV-ACLF and to develop a model to predict the outcomes for ACLF.Methods: Serum was collected from 41 chronic hepatitis B and 55 HBV-ACLF patients in addition to30 chronic asymptomatic HBV carriers as controls. The mi RNAs expressions were measured by real-time quantitative PCR(q-PCR). Statistical analyses were conducted to assess the ability of differentially expressed mi RNAs and other prognostic factors in identifying ACLF prognosis and to develop a new predictive model.Results: Real-time q-PCR indicated that serum miR-146 a-5 p, mi R-122-3 p and mi R-328-3 p levels were significantly upregulated in ACLF patients compared to chronic hepatitis B and chronic asymptomatic HBV carriers patients. In addition, multivariate regression analyses indicated that Na+, INR, gastrointestinal bleeding and mi R-122-3 p are all independent factors that are reliable and sensitive to the prognosis of HBV-ACLF. Therefore, we developed a new model for the prediction of HBV-ACLF disease state: Y = 0.402 × Na+-1.72 × INR-4.963 × gastrointestinal bleeding(Yes = 0; No = 1)-0.278 ×(mi R-122-3 p) + 50.449. The predictive accuracy of the model was 95.3% and the area under the receiver operating characteristic curve(AUROC) was 0.847.Conclusions: Expression levels of these mi RNAs(miR-146 a-5 p, mi R-122-3 p and mi R-328-3 p) positively correlate with the severity of liver inflammation in patients with ACLF and may be useful to predict HBV-ACLF severity.     

Circulating microRNAs in hepatitis B virus-infected patients

MicroRNAs (miRNAs) are stably present in human serum. The relationship between circulating miRNAs and hepatitis B virus (HBV) infected liver disease has not been previously reported. Applied Biosystems array-based miRNA expression profiling was performed on pooled sera obtained from identified groups of chronic asymptomatic carriers (ASC), patients with chronic hepatitis B (CHB) and HBV-associated acute-on-chronic liver failure (ACLF), as well as healthy controls (HC). Nine miRNAs were verified in more clinical samples by RT-PCR. The correlation between miRNAs expression and the relationship between miRNA levels and clinical characteristics was analysed. Results showed that circulating miRNAs were detected in all disease and control samples, and their numbers increased with symptom severity, from 37 in HC, 77 in ASC, 101 in CHB, to 135 in ACLF. The expression levels of most miRNAs were also up-regulated in HBV-infected patients when compared to HC. Expression of the liver-specific miR-122 was significantly up-regulated in HBV-infected patients. Concomitant regulation of miRNAs not in clusters was disrupted by HBV infection. However, such disruption was not observed for miRNAs in paralogous clusters. Furthermore, the level of miRNAs in the CHB serum was up-regulated most in hepatitis B e antigen-positive patients. The expression levels of miR-122 and miR-194 correlated negatively with the age of patients with CHB or ACLF. Functional analysis showed that miR-122 could inhibit HBV replication in Huh7 and HepG2 cells. In all, our study revealed that a number of miRNAs were differentially expressed during HBV infection and underscored the potential importance of miR-122 in the infection process.     

Masking the 5' terminal nucleotides of the hepatitis C virus genome by an unconventional microRNA-target RNA complex

Hepatitis C virus subverts liver-specific microRNA, miR-122, to upregulate viral RNA abundance in both infected cultured cells and in the liver of infected chimpanzees. These findings have identified miR-122 as an attractive antiviral target. Thus, it is imperative to know whether a distinct functional complex exists between miR-122 and the viral RNA versus its normal cellular target mRNAs. Toward this goal, effects on viral RNA abundance of mutated miR-122 duplex molecules, bound at each of the two target sites in the viral genome, were compared to effects on microRNA- or siRNA-mediated regulation of reporter target mRNAs. It was found that miR-122 formed an unusual microRNA complex with the viral RNA that is distinct from miR-122 complexes with reporter mRNAs. Notably, miR-122 forms an oligomeric complex in which one miR-122 molecule binds to the 5' terminus of the hepatitis C virus (HCV) RNA with 3' overhanging nucleotides, masking the 5' terminal sequences of the HCV genome. Furthermore, specific internal nucleotides as well as the 3' terminal nucleotides in miR-122 were absolutely required for maintaining HCV RNA abundance but not for microRNA function. Both miR-122 molecules utilize similar internal nucleotides to interact with the viral genome, creating a bulge and tail in the miR-122 molecules, revealing tandemly oriented oligomeric RNA complexes. These findings suggest that miR-122 protects the 5' terminal viral sequences from nucleolytic degradation or from inducing innate immune responses to the RNA terminus. Finally, this remarkable microRNA-mRNA complex could be targeted with compounds that inactivate miR-122 or interfere with this unique RNA structure.