代谢相关脂肪性肝病（MAFLD）是一种以肝脏脂肪蓄积为特征的疾病，是终末期肝病、原发性肝癌、肝移植的重要原因。MAFLD影响了全球约1/4的人口，给公共卫生带来了巨大的负担。遗传因素与环境因素在MAFLD发生发展中共同发挥作用，其中patatin样磷脂酶结构域蛋白3（ PNPLA3）基因rs738409多态性是MAFLD发生发展的决定性遗传因素之一。该文就 PNPLA3基因rs738409多态性在MAFLD发生发展中的作用机制，以及其在MAFLD的预测、诊断及治疗中的应用研究进展进行阐述。

Background::Heterotaxy (HTX) is a thoracoabdominal organ anomaly syndrome and commonly accompanied by congenital heart disease (CHD). The aim of this study was to analyze rare copy number variations (CNVs) in a HTX/CHD cohort and to examine the potential mechanisms contributing to HTX/CHD.Methods::Chromosome microarray analysis was used to identify rare CNVs in a cohort of 120 unrelated HTX/CHD patients, and available samples from parents were used to confirm the inheritance pattern. Potential candidate genes in CNVs region were prioritized via the DECIPHER database, and PNPLA4 was identified as the leading candidate gene. To validate, we generated PNPLA4-overexpressing human induced pluripotent stem cell lines as well as pnpla4-overexpressing zebrafish model, followed by a series of transcriptomic, biochemical and cellular analyses. Results::Seventeen rare CNVs were identified in 15 of the 120 HTX/CHD patients (12.5%). Xp22.31 duplication was one of the inherited CNVs identified in this HTX/CHD cohort, and PNPLA4 in the Xp22.31 was a candidate gene associated with HTX/CHD. PNPLA4 is expressed in the lateral plate mesoderm, which is known to be critical for left/right embryonic patterning as well as cardiomyocyte differentiation, and in the neural crest cell lineage. Through a series of in vivo and in vitro analyses at the molecular and cellular levels, we revealed that the biological function of PNPLA4 is importantly involved in the primary cilia formation and function via its regulation of energy metabolism and mitochondria-mediated ATP production. Conclusions::Our findings demonstrated a significant association between CNVs and HTX/CHD. Our data strongly suggested that an increased genetic dose of PNPLA4 due to Xp22.31 duplication is a disease-causing risk factor for HTX/CHD.

目的:探讨1例中性脂肪沉积症伴肌病(NLSDM)患儿的临床表型以及基因变异。方法:选择2021年2月因"发现高肌酸激酶(CK)升高2月余"就诊于郑州大学第一附属医院的1例NLSDM患儿作为研究对象，对其进行临床和实验室检查，并应用全外显子组测序进行基因变异分析，对候选变异进行Sanger测序家系验证。结果:患儿为9岁女性，表现为双下肢乏力、持续CK增高且营养心肌治疗无效。基因检测提示患儿 PNPLA2基因存在母源性c.32C>G(p.S11W)和父源性c.516C>G(p.N172K)复合杂合变异。根据美国美国医学遗传学与基因组学学会相关指南，上述变异均被评级为可能致病性变异(PM1＋PM2_Supporting＋PP3＋PP4)。 结论:PNPLA2基因c.32C>G(p.S11W)和c.516C>G(p.N172K)复合杂合变异考虑为该患儿肌无力和CK增高的遗传学病因。

目的 基于生物信息学分析探索腹泻型肠易激综合征(IBS-D)的关键基因及通路,为其诊断与治疗提供潜在的分子靶标.方法 分析基因表达综合数据库中GSE212719数据集,使用GEO2R识别差异表达基因(DEGs);通过DAVID数据库进行基因本体论(GO)富集分析和京都基因与基因组百科全书(KEGG)通路分析;使用STRING数据库构建蛋白质-蛋白质相互作用(PPI)网络,Cytoscape 3.10.1软件筛选IBS-D的功能模块和关键基因;使用基于R语言的微生信平台进行基因集富集分析(GSEA)并分析最显著基因集中前10个基因的转录水平,最后建立核心通路.结果 共182个DEGs,包括94个上调基因和88个下调基因;排序前三位的上调基因是MT-ATP6、FSIP2、FABP2,下调基因是LOC112268284、COL13A1、RNA5-8SN1.GO富集分析结果显示,主要集中在黏膜的先天免疫反应、核小体和核糖体组装等.KEGG通路分析结果显示,以核糖体、真核生物中的核糖体生物发生、系统性红斑狼疮为主要通路.PPI网络图由44个节点和336条边共同构建,发现10个核心Hub基因分别是 CDK1、TOP2A、CCNB1、KIF23、NDC80、CENPE、KNL1、ANLN、DEPDC1、HMMR.GSEA 发现,IBS-D 的致病通路可能与酸碱平衡异常、血清乳酸增加、乳酸酸中毒、线粒体异常和线粒体呼吸链活动异常等密切相关;最显著基因集中前 10 个基因是 NDUFA12、SLC26A3、PIGA、UQCRB、NDUFAF4、TRMT10C、ACAT1、GFM2、PNPLA8 和NDUFA4.关键信号通路以TOP2A和MT-ATP6为核心.结论 TOP2A和MT-ATP6基因上调可能与线粒体功能障碍导致血清乳酸增加相关,而COL13A1基因下调可能使肠道肌肉组织的结构受损和炎症增加,这些都可能与IBS-D的发生、发展有关.这一综合分析提供了 IBS-D的关键基因和通路信息,为进一步研究提供了新方向.

钠-葡萄糖耦联转运体2抑制剂(SGLT2i)是一类新型口服降糖药物,广泛应用于2型糖尿病患者的降糖治疗,但由于患者的遗传背景差异,常导致药物治疗的反应性多样.本文通过综述SGLT2i的药物基因组学研究报道,发现UGT1A9、UGT2B4、SLC5A2、ABCB1、PNPLA3、WFS1基因变异可能影响SGLT2i的药代动力学以及SGLT2i在改善非酒精性脂肪性肝病、减重等方面的降糖外效应,但尚无足够的临床证据支持基因多态性影响SGLT2i的降糖疗效.

目的 采用生物信息学方法探究心脏衰老的关键基因.方法 从基因表达综合数据库(Gene Expression Omnibus,GEO)中选择基因表达谱 GSE8146.通过 R软件进行相关分析,筛选出年轻小鼠与老年小鼠心脏中差异表达基因,利用 DAVID 6.8 在线分析工具对差异表达基因进行基因本体(Gene Ontology,GO)功能富集分析和京都基因与基因组百科全书(Kyoto Ency-clopedia of Genes and Genomes,KEGG)信号通路富集分析.基于 STRING 在线数据库进行蛋白互作(protein-protein interaction,PPI)网络分析获得关键基因.结果 共筛选出 55 个差异表达基因,其中上调基因 22 个,下调基因 33 个.差异表达基因显著富集于脂质代谢、脂肪酸代谢等过程,参与了过氧化物酶体增殖物激活受体(peroxisome proliferators-activated receptor,PPAR)、腺苷酸活化蛋白激酶(adenosine5'-monophosphate-activated protein kinase,AMPK)信号通路等通路功能.筛选出 Fasn、Pck1、Adipoq、Cpt1a、Pdk4、Pnpla2、Slc27a1、Hmgcs2、Cidec、Ucp3 等关键基因.结论 心脏衰老可能与细胞能量代谢障碍相关,Fasn、Pck1、Adipoq、Cpt1a、Pdk4、Pnpla2、Slc27a1、Hmgcs2、Ucp3 等关键基因及PPAR、AMPK信号通路等可能在心脏衰老的发生、发展中发挥重要作用.

目的 系统评价PNPLA3 rs738409基因突变与非酒精性脂肪性肝病肝损伤的相关性.方法 计算机检索Pub Med、CNKI、Embase、Ovid数据库,搜索有关PNPLA3 rs738409基因多态性与单纯非酒精性肝病肝损伤相关性的横断面研究,检索时限为建库至2017年4月,由2位研究人员独立筛选,提取数据资料后用STATA12.0软件进行Meta分析.结果 在PNPLA3 rs738409位点发生突变的患者体内,丙氨酸氨基转移酶、天门冬氨酸氨基转移酶水平明显高于未发生突变的人群,而在三酰甘油、胆固醇水平的研究中二者差异无统计学意义(P>0.05).结论 PNPLA3基因的突变与非酒精性脂肪性肝病肝损伤有密切相关性.

非酒精性脂肪性肝病(nonalcoholic fatty liver disease, NAFLD)是一种普遍存在的疾病,目前被认为是西方最常见的肝病[1],近年来在我国的发病率也愈来愈高[2].NAFLD是指在没有过量饮酒的情况下,肝脏中过多脂肪的积累.虽然其最初是良性的,但是会从单纯的非酒精性脂肪变性逐渐发展为非酒精性脂肪性肝炎(nonalcoholic steatohepatitis,NASH),随后进展为肝纤维化、肝硬化甚至肝癌.NAFLD的发生发展与多种因素相关,肥胖是其发病的重要危险因素.目前,"二、三次打击"学说是公认的 NAFLD 主要发病机制[3].第一次打击中,甘油三酯(triglyceride,TG)以脂滴的形式在5% 以上的肝细胞胞浆内积聚(脂肪变性),该阶段的脂肪变性是良性可逆的;第二次打击包括氧化应激(oxidative stress,OS;系脂肪酸过氧化使自由基形成)、心磷脂(存在于线粒体膜)过氧化导致线粒体功能障碍和更多的活性氧簇(reactive oxygen species, ROS)形成、促炎性细胞因子的形成、细胞凋亡和肠源性细菌内毒素血症等,导致肝细胞坏死和凋亡;第三次打击包括含类马铃薯糖蛋白磷脂酶结合域3(patatin-like phospholipase domain-containing 3,PNPLA3)基因的参与和受损的肝细胞再生.Oniki 等[4]指出 PNPLA3rs738409基因多态性(编码I148M)是NAFLD发生发展的主要遗传因素.虽然上述学说得到公认,但并不能完全解释 NAFLD 的发生机制.核因子E2相关因子2(Nuclear factor erythroid 2-related factor 2, Nrf2)是一组参与抗氧化/亲电体压力基因表达的正调控转录因子.近年来,Nrf2信号通路对NAFLD的调节作用也成为国内外的研究热点.Nrf2是重要的内源性抗氧化应激通路,与肝脏多种疾病密切相关.本文综述Nrf2信号通路在 NAFLD中的调节作用.

目的 对2个X-性连锁鱼鳞病(X-linked ichthyosis,XLI)家系进行基因检测及胎儿产前诊断. 方法 应用染色体核型分析、细菌人工染色体标记-磁珠鉴别/分离技术(bacterial artificial chromosomes on-BeadsTM,BoBs)、荧光原位杂交(fluorescence in situ hybridization,FISH)技术和微阵列单核苷酸多态性芯片(single nucleotide polymorphism array,SNP-array)技术,对未知鱼鳞病家族史的家系1和已知鱼鳞病家族史的家系2的羊水及外周血标本进行基因检测及胎儿产前分子诊断,并收集相关临床资料. 结果 (1)家系1:产前BoBs方法检测到家系1胎儿(Ⅳ-12)XC1探针为0.36～0.50,提示存在微缺失.孕妇(Ⅲ13) SNP-array检测结果显示Xp22.31区域存在1.68 Mb拷贝数缺失,丢失4个在线人类孟德尔遗传数据库(Online Mendelian Inheritance in Man,OMIM)基因(分别为HDHD1、STS、VCX和PNPLA4).胎儿SNP-array结果为arr[hg 19]Xp22.31(6 455 151-8 135 644)×0,提示缺失遗传自母亲.FISH分析的结果证实胎儿STS基因缺失,核型结果为46,XY.孕妇表妹(Ⅲ-21)及表外甥(Ⅳ-14)同样存在STS基因缺失,缺失大小与孕妇及胎儿一致.结果 Ⅳ-12足月剖宫产出生,出生时皮肤未见异常,生后1周腹部出现白色鳞屑广泛附着,天气干燥时症状加重.对该例婴儿随访至8月龄,未发现其他临床症状.(2)家系2:SNParray结果显示,孕妇(Ⅲ-21)、先证者(Ⅳ-16)及胎儿(Ⅳ-17)在Xp22.31区域存在1.2 Mb拷贝数缺失,丢失4个OMIM基因(分别为HDHD1、STS、VCX和PNPLA4).FISH结果验证家系2胎儿STS基因缺失.胎儿核型结果为46,XY.结果Ⅳ-17足月剖宫产出生,出生时皮肤未见异常;至10日龄时,腹部出现白色鳞屑广泛附着.对该例婴儿随访至4个月,未发现其他临床症状. 结论 联合运用BoBs、FISH和SNP-array等分子遗传学技术有助于XLI的诊断及遗传咨询.

Objective:To evaluate the effect of high concentration of chlorogenic acid (CGA) on non-alcoholic fatty liver disease (NAFLD) in normal and oleic acid (OA) treated HepG2 cells,as well as the underlying mechanism involved in the fat accumulation,oxidative stress and insulin resistance (IR) induced by CGA treatment.Methods:OA (0.5 mmol/L) induced hepatic steatosis was established in HepG2 cells as an in vitro model of NAFLD.The normal and OA-treated HepG2 cells were treated by CGA (0,0.5,1,and 2 mmol/L) for 24 h,then cellular lipid droplets,reactive oxygen species (ROS),and glucose uptake were evaluated by Oil Red O staining and cellular biochemical assays,respectively.Signaling pathways involved in adipogenesis including SREBP-1c and PNPLA3,oxidative stress,and IR including CYP2E1 and CYP4A,were investigated by Western blot and RT-qPCR.Results:CGA (0.5,1,and 2 mmol/L) treatment increased the cellular lipid droplets and the expression of SREBP-1c and PNPLA3 in the tested cells.Additionally,2-NBDG uptake was significantly increased,whereas the cellular ROS and protein levels of CYP2E1 and CYP4A were significantly decreased in OAtreated cells.Conclusion:Our results suggest that high concentrations of CGA ameliorated OA-induced oxidative damage and IR likely by inhibiting the expression of CYP2E1 and CYP4A,and promoted lipid accumulation by inducing the expression of SREBP-1c and PNPLA3 in the tested cells.