肠道菌群与胆汁酸代谢在代谢相关脂肪性肝病的发生发展中的作用CSCD

代谢相关脂肪性肝病(metabolic-dysfunction-associated fatty liver disease,MAFLD)已成为我国慢性肝病的主要病因之一,其发病率呈逐年上升趋势。MAFLD是代谢综合征累及肝脏的表现,其发生发展与肠道菌群失调和代谢功能障碍等密切相关。由于发病机制尚不明确,目前依旧缺乏有效的药物治疗方法。肠道菌群与胆汁酸代谢密切相关,胆汁酸可靶向法尼醇X受体(farnesoid X receptor,FXR)信号通路负反馈调控肠道菌群,同时肠道菌群通过一系列复杂的生化反应影响胆汁酸代谢。大量研究发现MAFLD的免疫应答受损及全身低度慢性炎症可导致胆汁酸代谢紊乱。此外,MAFLD常伴随肠道菌群失调。本文就肠道菌群与胆汁酸代谢在MAFLD发生发展中的作用作一综述,以期探寻治疗MAFLD潜在的新的靶点。     

肠道菌群对代谢相关性脂肪肝的影响及运动干预研究进展

大量研究表明,肠道菌群与神经退行性疾病和代谢性疾病等多种疾病的发生和发展息息相关,菌群的种类和数量会受到遗传、饮食习惯、运动等因素的影响。在代谢相关脂肪性肝病中,肠道菌群的部分代谢物通过增加肝脏脂肪变性、改变肠道黏膜通透性等方式对疾病的发展起到促进作用,菌群的种类和数量变化与病情进展的关系也被广泛研究,但是两者发生的先后顺序仍不十分明确。运动可以增加肠道有益菌群的种类和数量,同时改善高脂饮食导致的肠道菌群紊乱,并有效缓解代谢相关脂肪性肝病的病情,肠道菌群也能对机体的运动能力产生影响,但运动是如何通过肠道菌群来改善代谢相关脂肪性肝病的机制尚不十分明确。本文通过综述三者的相互关系来阐述肠道菌群和运动在代谢相关脂肪性肝病中发挥的重要作用。     

酒精性肝病与肠道菌群关系的研究进展

肠道菌群被认为是人体的"第二大脑",肝脏被称为人体内的"生化工厂",由于肠道与肝脏均起源于内胚层,且通过门静脉紧密相连,所以肝脏的各项机能都与肠道菌群息息相关。酒精性肝病是由于摄入酒精导致的慢性肝病之一,在全球范围内普遍存在。近年来的研究结果表明,酒精性肝病(alcoholic liver disease,ALD)的发生与发展与肠道菌群密切相关。本文就肠道菌群与ALD的关系作一综述,并对靶向肠道菌群治疗ALD的方法简要总结,以期对ALD的治疗提供新策略。     

肠道菌群与非酒精性脂肪肝相关性的研究进展

非酒精性脂肪肝(NAFLD)是我国最常见的慢性肝病之一,为非酒精性因素所致的肝细胞脂肪变为特征的综合征,包括单纯性脂肪肝(SFL)、非酒精性脂肪性肝炎(NASH)及其相关肝硬化和肝细胞癌(HCC)。人体肠道中的各种菌群发挥着不同的病理生理作用,与许多疾病密切相关,肠道菌群可以通过"肠-肝轴"影响NAFLD的发生发展,"二次打击"学说很好地解释了NAFLD的发病机制及其与肠道菌群的关系。益生元、益生菌可以很好地调节肠道菌群,与抗生素和手术相比更加廉价、无害、安全,有望成为预防和治疗NAFLD的新方法。本研究对肠道菌群与NAFLD相关性的研究进展加以综述。     

肠道菌群与肝脏疾病相关性

肠道菌群是一个复杂的微生态系统,其种类、数量、比例、定位等要素的平衡对宿主健康产生重大影响,尤其与消化系统关系紧密。肝脏是身体内以代谢功能为主的器官,大量研究显示,肠道菌群可对酒精性肝病、非酒精性肝病、肝性脑病、肝硬化、肝癌以及自身自身免疫性肝炎等肝病的发生发展产生重要影响。本文从肠道菌群与肝脏疾病的相关性,肠道菌群影响肝脏疾病的可能机制等方面进行综述,为以肠道菌群为靶点的肝病临床治疗研究提供借鉴。     

肠道菌群影响非酒精性脂肪性肝病的机制及应对策略

非酒精性脂肪性肝病(nonalcoholic fatty liver disease,NAFLD)的发病率逐年升高,已成为最常见的肝脏疾病之一。目前其发病机制未被完全阐明,尚无有效治疗药物。肠道菌群与人体共生,作为人体的“第二基因组”,其在消化、吸收及代谢中发挥重要作用。新近研究表明,肠道菌群已成为影响NAFLD发生、进展的重要因素,肠道菌群失调和肠肝轴紊乱与非酒精性单纯性脂肪肝(nonalcoholic fatty liver,NAFL)发展为非酒精性脂肪性肝炎(nonalcoholic steatohepatitis,NASH)、肝纤维化和肝细胞癌(hepatocellular carcinoma,HCC)密切相关。因此,肠道微生态干预有望成为预防或治疗NAFLD的新手段。本综述主要探讨肠道菌群异常对NAFLD/NASH发病过程、机制的影响及干预措施。     

慢性肝病发展中肠道菌群参与调控的分子机制

人体肠道内寄生着大量的肠道菌群,它们参与机体多种生命活动,其紊乱被认为与多种疾病密切相关。肝与肠道之间存在着特殊的解剖位置关系,二者相互作用,相互影响。肠道菌群通过肠-肝轴参与一系列生理病理反应,最终影响慢性肝疾病的发展。目前,有众多学者对肠道菌群在肝疾病中的作用进行了研究,但涉及其中具体的机制尚未探明。本文就肠道菌群通过参与Toll样受体(TLRs)活化加重肝纤维化;胆汁酸代谢调控非酒精性脂肪性肝病（NAFLD）;T细胞分化改善酒精性肝病（ALD);活性氧簇(ROS)生成影响肝癌(HCC)发展中的具体分子机制做一综述。     

肠道菌群与肝癌

肝癌是世界上最恶性的疾病之一,发病率居世界第六位,病死率居世界第四位。尽管近年来在肝癌的诊断和治疗方面取得了进展,但患者生存率和术后复发率仍然不尽人意。肠道菌群栖息于人类的消化道,介导人体内多种代谢反应,协助机体完成正常生命活动。目前大量的研究证实,慢性肝病患者（如酒精性肝炎、非酒精性脂肪性肝病和病毒性肝炎等）体内均存在一定程度的肠道菌群紊乱且与疾病的发生发展相关,可能是慢性肝病向肝癌进展的主要因素,因此靶向肠道菌群的诊疗手段可能为肝癌患者的治疗提供新的思路。在此基础上,本文总结大量相关文献,从肠道菌群促进肝癌的机制及其对肝癌的预防、诊断以及治疗等方面进行综述。     

胆汁酸和肠道菌群相互作用对非酒精性脂肪性肝病的影响

近年来,大量研究发现胆汁酸与肠道菌群相互作用对非酒精性脂肪性肝病的发生和发展有重要影响。胆汁酸主要在肝脏中合成,分泌进入肠道后不仅可以促进脂类物质的消化和吸收,还具有重要的生理信号和代谢调节作用,其能通过参与能量代谢和炎症反应影响非酒精性脂肪性肝病的进程。肠道菌群的代谢产物(如胆汁酸、短链脂肪酸、内生性乙醇和三甲胺等)对宿主的代谢表型、免疫稳态、炎症反应和病程进展等都有重要调节作用。本文主要综述了胆汁酸的合成、转运代谢与肠道菌群结构变化之间的互相作用和对话交流机制,揭示了肠道菌群结构紊乱和胆汁酸代谢异常对非酒精性脂肪性肝病的推动作用,以期为临床上治疗非酒精性脂肪性肝病提供全新的策略和方法。     

肠道微生态与骨质疏松症

骨质疏松症是一种骨代谢障碍所致的全身性骨骼疾病,严重威胁着老龄人群的身心健康。肠道微生态(intestinal microecology, GM)是人体内最重要且最为复杂的微生态系统,对营养吸收、免疫调节、免疫防御、生长发育等有重要作用。GM失衡与炎症性肠病、糖尿病、心血管疾病、帕金森病、骨质疏松症等疾病的发生发展密切相关。肠道菌群丰度及菌群结构的改变可能与骨量减少有关,且经益生菌、益生元及天然中草药改善GM失衡后,骨质疏松症得到改善。本文就GM与骨质疏松症之间的关系、可能机制及治疗进展进行综述。     

阿德福韦酯联合乙肝免疫球蛋白预防HBV 相关性终末期肝病肝移植术 后复发的临床研究

目的:探讨阿德福韦酯(HDV)联合乙肝免疫球蛋白(HBIg)预防HBV相关性终末期肝病患者肝移植术后HBV复发的临床疗效。方法:回顾性分析2005年6月～2009年6月北京市解放军第302医院因HBV相关性终末期肝病接受肝移植的60例患者的临床资料。60例患者根据治疗方法分为治疗组和对照组,治疗组采用HDV联合HBIg预防肝移植术后HBV复发,对照组采用拉米夫定(LAM)联合HBIg预防HBV复发。结果:两组患者随访期内未出现肾毒性表现。治疗组平均随访时间为(21.67±5.37)月,随访期内无复发。对照组平均随访时间为(21.83±6.02)月,随访期内有2例复发。两组术后复发率比较有显著性差异(P<0.05)。结论:HDV联合HBIg预防肝移植术后HBV复发近期疗效优于LAM联合HBIg。     

阿德福韦酯联合乙肝免疫球蛋白预防HBV相关性终末期肝病肝移植术后复发的临床研究

目的：探讨阿德福韦酯（HDV）联合乙肝免疫球蛋白（HBIg）预防HBV相关性终末期肝病患者肝移植术后HBV复发的临床疗效。方法：回顾性分析2005年6月-2009年6月北京市解放军第302医院因HBV相关性终末期肝病接受肝移植的60例患者的临床资料。60例患者根据治疗方法分为治疗组和对照组,治疗组采用HDV联合HBk预防肝移植术后HBV复发,对照组采用拉米夫定（LAM）联合HBIg预防HBV复发。结果：两组患者随访期内未出现肾毒性表现。治疗组平均随访时间为（21．67±5．37）月,随访期内无复发。对照组平均随访时间为（21．83±6．02）月,随访期内有2例复发。两组术后复发率比较有显著性差异（P〈0．05）。结论：HDV联合HBIg预防肝移植术后HBV复发近期疗效优于LAM联合HBIg。     

Modeling the transmission dynamics and control of hepatitis B virus in China

Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus (HBV) and is a major global health problem. HBV is the most common serious viral infection and a leading cause of death in mainland China. Around 130 million people in China are carriers of HBV, almost a third of the people infected with HBV worldwide and about 10% of the general population in the country; among them 30 million are chronically infected. Every year, 300,000 people die from HBV-related diseases in China, accounting for 40-50% of HBV-related deaths worldwide. Despite an effective vaccination program for newborn babies since the 1990s, which has reduced chronic HBV infection in children, the incidence of hepatitis B is still increasing in China. We propose a mathematical model to understand the transmission dynamics and prevalence of HBV infection in China. Based on the data reported by the Ministry of Health of China, the model provides an approximate estimate of the basic reproduction number R₀=2.406. This indicates that hepatitis B is endemic in China and is approaching its equilibrium with the current immunization program and control measures. Although China made a great progress in increasing coverage among infants with hepatitis B vaccine, it has a long and hard battle to fight in order to significantly reduce the incidence and eventually eradicate the virus.     

Hepatitis B Virus X Protein-Induced Aberrant Epigenetic Modifications Contributing to Human Hepatocellular Carcinoma Pathogenesis

Hepatocellular carcinoma (HCC) remains one of the most prevalent malignant diseases worldwide, and the majority of cases are related to hepatitis B virus (HBV) infection. Interactions between the HBV-encoded X (HBx) protein and host factors are known to play major roles in the onset and progression of HBV-related HCC. These dynamic molecular mechanisms are extremely complex and lead to prominent changes in the host genetic and epigenetic architecture. This review summarizes the current knowledge about HBx-induced epigenetic changes, including aberrations in DNA methylation, histone modifications, and microRNA expression, and their roles in HBV-infected liver cells and HBV-related HCC. Moreover, the HBx-mediated epigenetic control of HBV covalently closed circular DNA (cccDNA) is also discussed. Although this field of study is relatively new, the accumulated evidence has indicated that the epigenetic events induced by HBx play important roles in the development of HBV-related HCC. Ongoing research will help to identify practical applications of the HBV-related epigenetic signatures as biomarkers for early HCC detection or as potential targets to prevent and treat HBV-related HCC.     

乙型肝炎病毒树鼩体内慢性感染模型的研究历程和展望

乙型肝炎病毒(HBV)感染是全球和我国的重要健康问题,建立方便有效的HBV感染动物体内模型是开展HBV相关基础和临床研究的重要前提。该实验室地处乙型肝炎和肝癌高发流行的广西地区,自建立以来一直以肝癌的病因、发病机制和化学预防作为主要研究方向,于20世纪80年代初开始树鼩体内感染HBV模型方面的研究并持续至今。该文对此研究历程作一概述,并重点介绍关于用新生树鼩慢性感染HBV的新进展。     

Blockade of preS2 down-regulates the apoptosis of HepG2.2.15 cells induced by TRAIL

The TNF-related apoptosis-inducing ligand (TRAIL) has recently been implicated in the death of hepatocytes under infectious but not normal conditions. Our previous studies showed that both the whole HBV genome and its HBx protein enhanced TRAIL-induced hepatocyte apoptosis. We report here that preS2-containing viral proteins are also potent regulators of TRAIL-induced apoptosis. HBV-transfected hepatoma cell line, HepG2.2.15, pretreated with antisense oligonucleotide against preS2 gene, showed a lower sensitivity towards TRAIL-induced apoptosis. However, this effect might not be related with the expression level of TRAIL receptors. These results establish that besides HBx, preS2 viral proteins are also involved in enhancing TRAIL-induced hepatocyte apoptosis. The novel role of preS2 would be useful to further unravel the mechanisms of imbalanced apoptosis during HBV infection and provides a potential therapeutic target for HBV-related diseases.     

肠道微生物与过敏性疾病关系研究进展

目前,过敏性疾病的防治主要依赖于使用抗生素,然而抗生素的滥用已造成了严重的危害。近年来随着肠道微生物相关研究的不断深入以及人们对过敏性疾病的日益关注与重视,肠道微生物与过敏性疾病间的关系逐渐受到科学家们的关注。调整肠道菌群结构可能为过敏性疾病的防治提供新的思路。目前对肠道微生物与过敏性疾病间的相关性报道相对较少且未有深层次的剖析。本文总结了关于肠道微生物与过敏性疾病关系的研究起源、发展与现状,旨在为过敏性疾病的防治提供新策略。     

乙肝病毒感染对细胞基本自噬的影响

【目的】慢性乙肝病毒(Hepatitis B virus,HBV)感染在肝硬化和肝癌的发生过程中起着重要的作用,通过研究HBV感染对细胞基本自噬的影响,为HBV感染诱发肝癌以及HBV的免疫逃逸机理研究提供新的思路。【方法】本研究利用乙肝病毒表达质粒瞬时或稳定转染不同肝细胞,通过计数绿色荧光蛋白(greenfluorescent protein,GFP)聚集数目检测自噬小体形成,western blot检测LC3(microtubule-associated proteinlight chain 3,微管相关蛋白质轻链3)脂酰化和p62的降解,通过构建HBV B型和C型X蛋白(HBx)的表达质粒并瞬时转染肝癌细胞和正常肝细胞,对不同基因型X蛋白对细胞自噬的影响进行了分析。【结果】乙肝病毒感染后促进了LC3的脂酰化和p62的降解,增加了自噬小体的形成,增强了细胞的基本自噬。进一步研究发现,HBV感染增强的细胞基本自噬水平由HBx所引发,且C型HBx比B型对细胞基本自噬的增加更加显著。【结论】HBV通过HBx增强细胞的基本自噬,且不同基因型HBx对细胞基本自噬的增强程度不同,为进一步阐明HBV感染机理奠定了基础。     

Roles of the gut microbiota in severe SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide. The pathophysiological mechanisms linking gut dysbiosis and severe SARS-CoV-2 infection are poorly understood, although gut microbiota disorders are related to severe SARS-CoV-2 infections. The roles of the gut microbiota in severe SARS-CoV-2 infection were compared with those in respiratory viral infection, which is an easily understood and enlightening analogy. Secondary bacterial infections caused by immune disorders and antibiotic abuse can lead to dysregulation of the gut microbiota in patients with respiratory viral infections. The gut microbiota can influence the progression of respiratory viral infections through metabolites and the immune response, which is known as the gut–lung axis. Angiotensin-converting enzyme 2 is expressed in both the lungs and the small intestine, which may be a bridge between the lung and the gut. Similarly, SARS-CoV-2 infection has been shown to disturb the gut microbiota, which may be the cause of cytokine storms. Bacteria in the gut, lung, and other tissues and respiratory viruses can be considered microecosystems and may exert overall effects on the host. By referencing respiratory viral infections, this review focused on the mechanisms involved in the interaction between SARS-CoV-2 infections and the gut microbiota and provides new strategies for the treatment or prevention of severe SARS-CoV-2 infections by improving gut microbial homeostasis.     

Small rodent models of hepatitis B and C virus replication and pathogenesis

The narrow host range of infection supporting the long-term propagation of hepatitis B and C viruses is a major limitation that has prevented a more thorough understanding of persistent infection and t...