High patatin like phospholipase domain containing 8 expression as a biomarker for poor prognosis of colorectal cancer

BACKGROUND Patatin like phospholipase domain containing 8(PNPLA8)has been shown to play a significant role in various cancer entities.Previous studies have focused on its roles as an antioxidant and in lipid peroxidation.However,the role of PNPLA8 in colorectal cancer(CRC)progression is unclear.AIM To explore the prognostic effects of PNPLA8 expression in CRC.METHODS A retrospective cohort containing 751 consecutive CRC patients was enrolled.PNPLA8 expression in tumor samples was evaluated by immunohistochemistry staining and semi-quantitated with immunoreactive scores.CRC patients were divided into high and low PNPLA8 expression groups based on the cut-off va-lues,which were calculated by X-tile software.The prognostic value of PNPLA8 was identified using univariate and multivariate Cox regression analysis.The over-all survival(OS)rates of CRC patients in the study cohort were compared with Kaplan-Meier analysis and Log-rank test.RESULTS PNPLA8 expression was significantly associated with distant metastases in our cohort(P=0.048).CRC patients with high PNPLA8 expression indicated poor OS(median OS=35.3,P=0.005).CRC patients with a higher PNPLA8 expression at either stage I and II or stage III and IV had statistically significant shorter OS.For patients with left-sided colon and rectal cancer,the survival curves of two PN-PLA8-expression groups showed statistically significant differences.Multivariate analysis also confirmed that high PNPLA8 expression was an independent prog-nostic factor for overall survival(hazard ratio HR=1.328,95%CI:1.016-1.734,P=0.038).

血管紧张素Ⅱ1型受体基因rs3772622位点多态性与非酒精性脂肪性肝病发病风险的相关性分析

目的探究血管紧张素Ⅱ1型受体（AGTR1）rs3772622位点多态性与非酒精性脂肪性肝病（NAFLD）的关系及该位点与patatin样磷酯酶域（PNPLA3）rs738409位点多态性的交互作用。方法选取2013年9月-2014年9月青岛市市立医院经临床B超诊断为NAFLD的患者241例及正常对照人群205例,采用PCR及基因型检测方法对AGTR1 rs3772622位点和PNPLA3 rs738409位点进行检测。运用统计学方法检测两位点等位基因频率、基因型频率及各项临床数据资料生化结果。计量资料行独立样本t检验,计数资料行χ2检验。通过二元Logistic回归分析AGTR1 rs3772622及PNPLA3 rs738409突变基因型罹患NAFLD的风险,使用广义多因子降维法（GMDR）研究两位点之间的交互作用。结果 AGTR1 rs3772622位点基因型及等位基因在NAFLD组与对照组中的分布频率差异无统计学意义（P〉0.05）。相对于野生型,AGTR1 rs3772622位点突变型并未增加NAFLD的发病风险（P〉0.05）,PNPLA3 rs738409突变型人群患NAFLD的风险是野生型的2.09倍[OR=2.09,95%可信区间（95%CI）：1.35~3.23,P=0.001]。AGTR1 rs3772622位点与PNPLA3 rs738409位点联合作用使NAFLD的发病风险明显增加（OR=3.60,95%CI：1.50~6.23,P〈0.001）。两突变基因双携带者与PNPLA3 rs738409单突变基因携带者生化指标的比较发现ALT、AST在两组间差异有统计学意义（P值均〈0.05）。结论中国人群中AGTR1 rs3772622位点多态性对NAFLD的发生发展无关。但其位点突变可增加PNPLA3rs738409位点突变患者罹患NAFLD的风险。

蓝莓联合益生菌对非酒精性脂肪性肝病模型大鼠PNPLA3和SREBP-1c表达的影响

目的观察含patatin样磷脂酶域3(PNPLA3)和胆固醇调节元件结合蛋白(SREBP)1c在蓝莓联合益生菌对非酒精性脂肪性肝病(NAFLD)模型大鼠干预实验中的表达,并探讨其在NAFLD中的作用机制。方法清洁级SD大鼠36只分为正常组(NG)、模型组(MG)、自然恢复组(SRG)、蓝莓组(BG)、益生菌组(PG)和蓝莓联合益生菌组(BPG)。实验结束后,制作组织切片,观察血清学、组织学形态变化,检测PNPLA3和SREBP-1c基因及蛋白表达情况。多组间比较用单因素方差分析,方差齐时用SNK-q检验,方差不齐时用Tamhane's-T2检验。结果 6组间在肝脏指数、ALT、TC、TG、LDL和HDL上差异均有统计学意义(F值分别为384.908、188.554、75.523、94.667、95.235、132.586,P值均<0.01)。6组间NAFLD活动度积分差异有统计学意义(F=71.896,P<0.01),其中BPG组较MG、SRG、BG、PG组下降最为显著(P值均<0.01)。6组肝组织表达PNPLA3和SREBP-1c阳性率差异均有统计学意义(F值分别为175.527、110.504,P值均<0.01),其中BPG组较MG、SRG、BG、PG组下降最为显著(P值均<0.01)。PNPLA3和SREBP-1c的mRNA和蛋白表达各组间差异有统计学意义(F值分别为375.822、410.379、288.940、116.054,P值均<0.01)。其中BPG组的PNPLA3和SREBP-1C的mRNA和蛋白表达较MG、SRG、BG、PG组明显下降(P值均<0.01)。结论蓝莓联合益生菌能有效改善NAFLD的病理组织结构,减轻肝细胞脂肪变性,其机制可能是蓝莓与益生菌联合可减轻炎症因子诱发的炎症效应,下调SREBP-1c的表达,从而减弱PNPLA3基因转录,增强胆固醇代谢,减少脂质沉积,是NAFLD的一个辅助治疗方案。

PNPLA3 I148M (rs738409) SNP与肝硬化及肝细胞癌关系的研究进展

含patatin样磷脂酶域3(patatin-like phospholipase domain containing 3,PNPLA3),又称脂肪营养素.大量位于肝细胞膜上并参与脂质代谢.rs738409处基因突变致148位异亮氨酸被蛋氨酸取代(148 isoleucine to Methionine protein variant,I148M).近年来全基因组分析显示PNPLA3 I148M与肝脏脂肪含量、血清肝酶水平、纤维化程度明显相关,研究显示PNPLA3 I148M与酒精性肝硬化进程及其所致肝细胞癌的临床转归及预后、慢性丙型肝炎的临床转归显著相关.PNPLA3 I148M在肝病进展中扮演重要角色,可作为肝细胞癌的一个独立危险因素.

组蛋白乙酰化修饰调控NF-κB驱动的PNPLA3基因表达的机制初探

目的探讨禁食/再喂食后小鼠肝脏Patatin样磷脂酶域蛋白3(PNPLA3)基因启动子核因子-κB(NF-κB)结合区域组蛋白H3K9乙酰化(H3K9ac)水平以及相关去乙酰化酶(HDAC)和乙酰化转移酶(HAT)的变化特点。方法根据体质量将18只C57BL/6小鼠随机分为3组各6只,分别为自由饮食组、禁食组(夜间饥饿24 h)和再喂食组(饥饿24 h后再自由摄食高蔗糖含量饲料12 h),分别予自由饮食、禁食和禁食后再喂食干预,检测并比较各组肝脏PNPLA3、NF-κB、HDAC(SIRT1、SIRT6)和HAT(GCN5、Elp3)基因表达情况,用染色质免疫共沉淀-定量PCR检测H3K9ac富集水平,并分析H3K9ac与PNPLA3表达的相关性。结果 3组比较,C57BL/6小鼠肝脏PNPLA3、NF-κB基因表达在禁食时下调,再喂食后又上调(P均<0.001)。H3K9ac水平变化与PNPLA3变化趋势一致(P均<0.05),相关分析提示两者具有相关性(rs=0.958, P <0.001);禁食组SIRT1和SIRT6表达水平较自由饮食组高,再喂食组两者水平均下降(P均<0.05),与H3K9ac变化趋势相反;GCN5、Elp3表达变化与SIRT1及SIRT6类似(P均<0.05)。结论 SIRT1和SIRT6相关H3K9去乙酰化涉及饮食调节NF-κB驱动的PNPLA3的表达。

含patatin样磷脂酶结构域蛋白7通过过氧化物酶体增殖物激活受体γ促进巨噬细胞M2型极化

溶血磷脂酰胆碱(LPC)在免疫反应、组织炎症和重塑中调控巨噬细胞极化的动态和整体过程。含patatin样磷脂酶结构域蛋白7(PNPLA7)是近年发现的优先水解LPC的溶血磷脂酶。然而,直到现在仍不清楚PNPLA7在巨噬细胞极化中的表达和作用。本研究发现,PNPLA7在白细胞介素4(IL-4)刺激的巨噬细胞向替代激活(M2)表型的极化过程中上调(P<0.05)。本文发现,PNPLA7的敲低和过表达分别降低和增加了M2标记基因,包括精氨酸酶1(Arg1)和类几丁质酶3(Ym1)的表达(P<0.05)。进一步的研究表明,PNPLA7在M2极化过程中调节过氧化物酶体增殖物激活受体γ(PPARγ)在mRNA和蛋白质水平上的表达(P<0.05)。然而,信号转导和转录激活因子6(STAT6)的磷酸化不受PNPLA7的影响。这些发现表明,PNPLA7通过PPARγ相关机制促进巨噬细胞抗炎M2型极化。

PNPLA3 I148M polymorphism and progressive liver disease

The 148 Isoleucine to Methionine protein variant(I148M)of patatin-like phospholipase domain-containing 3(PNPLA3),a protein is expressed in the liver and is involved in lipid metabolism,has recently been identified as a major determinant of liver fat content.Several studies confirmed that the I148M variant predisposes towards the full spectrum of liver damage associated with fatty liver:from simple steatosis to steatohepatitis and progressive fibrosis.Furthermore,the I148M variant represents a major determinant of progression of alcohol related steatohepatitis to cirrhosis,and to influence fibrogenesis and related clinical outcomes in chronic hepatitis C virus hepatitis,and possibly chronic hepatitis B virus hepatitis,hereditary hemochromatosis and primary sclerosing cholangitis.All in all,studies suggest that the I148M polymorphism may represent a general modifier of fibrogenesis in liver diseases.Remarkably,the effect of the I148M variant on fibrosis was independent of that on hepatic steatosis and inflammation,suggesting that it may affect both the quantity and quality of hepatic lipids and the biology of non-parenchymal liver cells besides hepatocytes,directly promoting fibrogenesis.Therefore,PNPLA3 is a key player in liver disease progression.Assessment of the I148M polymorphism will possibly inform clinical practice in the future,whereas the determination of the effect of the 148M variant will reveal mechanisms involved in hepatic fibrogenesis.

PNPLA3 rs139051 is associated with phospholipid metabolite profile and hepatic inflammation in nonalcoholic fatty liver disease

AIM To investigate the effect of PNPLA3 polymorphisms on serum lipidomics and pathological characteristics in nonalcoholic fatty liver disease(NAFLD).METHODS Thirty-four biopsy-proven NAFLD patients from Northern, Central, and Southern China were subjected to stratification by genotyping their single nucleotide polymorphisms(SNPs) in PNPLA3. Ultra performance liquid chromatography-tandem mass spectrometry was then employed to characterize the effects of PNPLA3 SNPs on serum lipidomics. In succession, correlation analysis revealed the association of PNPLA3-related lipid profile and hepatic pathological characteristics on a basis of steatosis, activity, and fibrosis assessment. The variant-based scoring of hepatocyte steatosis, ballooning, lobular inflammation, and liver fibrosis was finally performed so as to uncover the actions of lipidomics-affecting PNPLA3 SNPs in NAFLD-specific pathological alterations. RESULTS PNPLA3 SNPs(rs139051, rs738408, rs738409, rs 2072906, rs2294918, rs2294919, and rs4823173) demonstrated extensive association with the serum lipidomics, especially phospholipid metabolites [lysophosphatidylcholine(LPC), lysophosphatidylcholine plasmalogen(LPCO), lysophosphatdylethanolamine(LPE), phosphatidylcholine(PC), choline plasmalogen(PCO), phosphatidylethanolamine(PE), ethanolamine plasmalogen(PEO)], of NAFLD patients. PNPLA3 rs139051(A/A genotype) and rs2294918(G/G genotype) dominated the up-regulatory effect on phospholipids of LPCs(LPC 17:0, LPC 18:0, LPC 20:0, LPC 20:1, LPC 20:2) and LPCOs(LPC O-16:1, LPC O-18:1). Moreover, subjects with high-level LPCs/LPCOs were predisposed to low-grade lobular inflammation of NAFLD(rho:-0.407 to-0.585, P < 0.05-0.001). The significant correlation of PNPLA3 rs139051 and inflammation grading [A/A vs A/G + G/G: 0.50(0.00, 1.75) vs 1.50(1.00, 2.00), P < 0.05] further demonstrated its pathological role based on the modulation of phospholipid metabolite profile.CONCLUSION The A/A genotype at PNPLA3 rs139051 exerts an upregulatory effect on serum phospholipids of LPCs and LPCOs, which are associated with low-grade lobular inflammation of NAFLD.

PNPLA3基因表达以及干扰腺病毒的构建及鉴定

目的构建糖脂代谢和脂肪肝相关基因PNPLA3过表达以及干扰腺病毒载体并加以鉴定。方法根据PNPLA3基因序列设计过表达以及干扰序列引物,定向克隆入穿梭载体pAdTrack-CMV的BglⅡ和XhoⅠ位点,干扰序列克隆入pAdTrack-U6穿梭载体,PmeⅠ酶切线性化穿梭质粒与腺病毒载体(pAdEasy-1质粒)共转化E.coliBJ5183感受态细菌产生重组腺病毒载体,用PacⅠ酶切线性化的回收质粒转染293A细胞包装腺病毒颗粒,在倒置荧光显微镜下观察293A细胞绿色荧光蛋白的表达,并初步观察其感染小鼠原代细胞的效率。结果测序、酶切鉴定证实,构建出了PNPLA3基因过表达及干扰腺病毒载体。包装的腺病毒浓缩悬液滴度为1.5×1011VP/mL。以120感染复数感染小鼠肝脏原代细胞,感染效率可达到90%以上,干扰效率超过80%以上。结论成功构建了PNPLA3基因的过表达以及干扰腺病毒载体。

中国汉族人群PNPLA3 rs738409(C>G)基因多态性与肝硬化病因学的相关性

目的:探究在中国汉族人群中,含patatin样磷脂酶域3(patain-like phospholipase domaincontaining protein 3,PNPLA3)I148M基因变异与酒精性肝硬化、慢性乙型病毒性肝炎肝硬化及慢性丙型病毒性肝炎肝硬化易感性及肝脏损伤程度、预后是否存在相关性.方法:本研究纳入224例中国汉族酒精性肝硬化、慢性丙型病毒性肝炎肝硬化、慢性乙型病毒性肝炎肝硬化患者,其中,慢性乙型病毒性肝炎肝硬化患者88例,酒精性肝硬化患者83例,慢性丙型病毒性肝炎肝硬化患者53例及200名健康人群作为对照组.采用探针法基因分型检测PNPLA3 rs738409与肝硬化之间的相关性.结果:PNPLA3 I148M rs738409 G等位基因型在酒精性肝硬化(OR=1.902,P<0.001)及慢性乙型肝炎肝硬化(OR=1.452,P=0.047)与健康对照组中的频率分布存在显著差异;丙型肝炎肝硬化与健康对照组中的等位基因频率分布差异无统计学意义(P=0.056).并未得出PNPLA3 I148M rs738409 C>G与肝硬化原发性肝细胞癌相关(P=0.965).结论:PNPLA3 rs738409 C>G在中国汉族人群中与酒精性肝硬化及慢性乙型肝炎肝硬化易感性存在相关性.

Insulin resistance and steatosis in HBV-HCV co-infected patients: Role of PNPLA3 polymorphisms and impact on liver fibrosis progression

AIM:To evaluate steatosis,insulin resistance(IR)and patatin-like phospholipase domain-containing 3(PNPLA3) and their relation to disease progression in hepatitis B and C viruses(HCV-HBV) coinfected patients.METHODS:Three hundred and thirty patients with biopsy proven chronic hepatitis were enrolled:66 had HBV-HCV,66 HBV and 198 HCV infection.Prevalence of steatosis,IR and PNPLA3 polymorphisms and their relation to anthropometric,biochemical,virological and histological parameters were evaluated.RESULTS:Prevalence of steatosis in group HBV-HCV was similar to that in HCV(47.0% vs 49.5%,respec-tively);group HBV showed the lowest steatosis(33.3%).Group HBV-HCV had a lesser degree of steatosis than HCV(P = 0.016),lower HCV RNA levels(P = 0.025) and lower prevalence and degree of IR(P = 0.01).PNPLA3 polymorphisms were associated with steatosis.Group HBV-HCV showed higher levels of liver fibrosis than group HCV(P = 0.001),but similar to that ob-served in HBV group.In HBV-HCV group,liver fibrosis was not associated with steatosis,IR or PNPLA3.HBV infection was the independent predictor of advanced liver fibrosis.CONCLUSION:HBV-HCV co-infected patients have lower degree of hepatic steatosis,IR and HCV RNA than HCV mono-infected;co-infected patients showed a more rapid liver fibrosis progression that seems to be due to the double infection and/or HBV dominance.

外周血PNPLA3 rs738409基因多态性与非酒精性脂肪性肝病遗传易感性研究

目的分析patatin样磷脂酶结构域蛋白3(PNPLA3)rs738409基因多态性与非酒精性脂肪性肝病(NAFLD)遗传易感性的关系。方法2017年11月~2019年11月我院诊治的162例NAFLD患者和同期体检的100例健康人,采用聚合酶链式反应-限制性片段长度多态性检测外周血PNPLA3 rs738409位点多态性。结果NAFLD组PNPLA3基因rs738409位点GG基因型频率为37.0%,G等位基因频率为58.3%,显著高于健康人(分别为11.0%和34.0%,P<0.05),而GC和CC基因型频率分别为42.6%和20.4%,C等位基因频率为41.7%,与健康人的46.0%、43.0%和66.0%比,差异无统计学意义(P>0.05);73例GG基因型的NAFLD患者血清ALT和AST水平分别为(118.5±20.3)U/L和(85.2±14.7)U/L,显著高于65例GC基因型患者[分别为(93.3±16.4)U/L和(59.6±10.3)U/L,P<0.05]或24例CC基因型患者[分别为(65.9±11.8)U/L和(31.9±5.5)U/L,P<0.05];GG和GC基因型NAFLD患者血清TG水平分别为(2.0±0.5)mmol/L和(1.6±0.4)mmol/L,均显著高于CC基因型NAFLD患者[(1.1±0.2)mmol/L,P<0.05]。结论本研究结果提示PNPLA3 rs738409基因多态性与NAFLD遗传易感性有关,其影响机制有待进一步研究明确。

不同研究方法在PNPLA3 I148M SNP诱导非酒精性脂肪性肝病发生、发展中的作用

非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)是引起慢性肝病最常见的原因。近年来研究发现,除外肥胖、胰岛素抵抗(IR)、高脂血症等危险因素,遗传因素在其发病中发挥重要的作用。PNPLA3,又称脂肪营养素,与脂质代谢密切相关。rs738409处基因SNP导致148位异亮氨酸被蛋氨酸取代,自2008年全基因组分析证实了PNPLA3 I148M与NAFLD发生、发展的相关性,此后学者采用了多种研究方法以解释两者之间可能的机制。本文从人群研究、动物实验、细胞实验等几个方面来阐述PNPLA3 I148M SNP与NAFLD的相关性。

酒精性肝硬化患者血CTLA-4和PNPLA3基因多态性及其临床意义分析

目的探讨细胞毒性T淋巴细胞相关抗原4(CTLA-4)和Patatin样磷脂酶3(PNPLA3)基因多态性与酒精性肝硬化发病的关系。方法2017年1月~2019年1月我院治疗的酒精性肝硬化患者110例和同期健康人100例,采用聚合酶链反应-限制性片段长度多态性检测血CTLA-4基因rs4675369位点和PNPLA3基因rs738409位点多态性。结果肝硬化患者CTLA-4基因rs4675369位点为AA型、AG型和GG型比率分别为26.4%、49.1%和24.6%,与健康人的26.0%、50.0%和24.0%比,无显著性差异(P>0.05),等位基因A和G比率分别为50.9%和49.1%,与健康人的51.0%和49.0%比,也无显著性差异(P>0.05);肝硬化患者PNPLA3基因rs738409位点GG基因型和等位基因G比率分别为17.2%和38.2%,显著高于健康人的4.0%和24.0%(P<0.05);血CTLA-4基因rs4675369位点AA型、AG型和GG型和PNPLA3基因rs738409位点CC型、CG型和GG型肝硬化患者血清丙氨酸氨基转移酶、天门冬氨酸氨基转移酶、谷氨酰转肽酶和碱性磷酸酶水平之间比,差异均无统计学意义(P>0.05)。结论本研究结果未提示CTLA-4基因多态性与酒精性肝硬化发病存在相关关系,而PNPLA3基因多态性与酒精性肝硬化发病的关系也需要进一步研究明确。

PNPLA3 rs738409 underlies treatment response in nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease(NAFLD)has now become the leading cause of chronic liver disease with its growing incidence worldwide.Patatin-like phospholipase domain-containing protein 3(PNPLA3)rs738409 C>G reflects one of the critical genetic factors that confers high-risk to NAFLD.However,the role of PNPLA3 polymorphism in NAFLD treatment remains uncertain.Here,the present review reveals that NAFLD patients with G-allele at PNPLA3 rs738409(PNPLA3 148M variant)are sensitive to therapies of lifestyle modification,dipeptidyl peptidase-4 inhibitors,and bariatric surgery.They exhibit much significant reduction of liver fat content,in concurrence with weigh loss and abolished insulin resistance,as compared to those of C-allele carriers.In contrast,patients bearing PNPLA3 rs738409 C-allele(PNPLA3 148I variant),instead of G-allele,demonstrate greater beneficial effects by omega-3 poly-unsaturated fatty acids and statin intervention.Improved adipose tissue-liver interaction and decrease in intrahepatic triglyceride efflux may contribute to the PNPLA3 rs738409related diversities in therapeutic efficacy.Therefore,PNPLA3 rs738409 underlies the response to a variety of treatments,which warrants a personalized,precise medicine in NAFLD on the basis of genotype stratification.

慢性HBV感染者外周血PNPLA3/PRKAA1基因多态性与肝硬化发生关系研究

目的探讨Patatin样磷脂酶域蛋白3(PNPLA3)和腺苷活化蛋白激酶α1亚基(PRKAA1)基因多态性与感染HBV后肝硬化发生的关系。方法2016年1月~2021年7月我院诊治的乙型肝炎肝硬化患者101例和同期慢性无症状HBV携带者90例,采用聚合酶链反应-限制性片段长度多态性检测血浆PNPLA3基因rs738409、rs139047、rs2294919和PRKAA1基因rs3792822、rs10036575、rs154268位点多态性,应用Logistic回归分析疾病风险关联。结果肝硬化组PNPLA3基因rs139047位点AA、GA、GA基因型比率分别为18.8%、51.5%和29.7%,与HBV携带者的16.7%、51.1%和32.2%比,无显著性差异(P>0.05),rs2294919位点CC、TC、TT基因型比率分别为41.6%、45.5%和12.9%,与HBV携带者的38.9%、50.0%和11.1%比,无显著性差异(P>0.05);PRKAA1基因rs3792822位点GG、GA、AA基因型比率分别为54.5%、38.6%和6.9%,与HBV携带者的55.6%、37.8%和6.7%比,无显著性差异(P>0.05),rs154268位点CC、CT、TT基因型比率分别为5.0%、35.6%和59.4%,与HBV携带者的4.4%、34.4%和61.1%比,无显著性差异(P>0.05);肝硬化组PNPLA3基因rs738409位点GG基因型和等位基因G比率分别为19.8%和44.6%,显著高于HBV携带者的8.9%和29.4%(P<0.05);肝硬化组PRKAA1基因rs10036575位点CC基因型和等位基因C比率分别为38.6%和63.9%,显著高于HBV携带者的23.3%和45.5%(P<0.05);经非条件Logistic回归模型分析显示PNPLA3基因rs738409位点GG基因型【OR为1.605(95%CI:1.150~2.239)】和PRKAA1基因rs10036575位点CC基因型【OR值为1.507((95%CI:1.097~2.070)】是影响感染HBV后肝硬化发生的危险基因型。结论感染HBV后发生肝硬化可能与某些特殊基因有关,研究PNPLA3基因和PRKAA1基因可能有助于阐明其中的分子机制。

Patatin样磷酯酶结构域蛋白3基因rs738409位点多态性与非酒精性脂肪肝易感性关系的Meta分析

目的 探讨Patatin样磷酯酶结构域蛋白3（PNPLA3）基因rs738409位点多态性与非酒精性脂肪肝易感性关系.方法 检索PubMed以及中文数据库（中国生物医学文献数据库、中国知网、万方数据库、维普数据库）,收集有关PNPLA3基因rs738409位点多态性与脂肪肝易感性的病例对照研究,提取文献相关数据进行Meta分析,以病例组与对照组PNPLA3基因rs738409位点各种基因模型的OR直及其95％CI为效应指标,并根据研究人群种族进行亚组分析.结果 共28篇研究符合纳入标准,累计病例数6 216例,对照组8 218例.Meta分析显示,PNPLA3基因rs738409多态性与非酒精性脂肪肝易感性有关联[纯合子比较模型（GGvs.CC）：OR=2.42,95％CI：1.83～3.21,P＜0.001;杂合子比较模型（CGvs.CC）：OR=1.28,95％CI：1.15 ～ 1.43,P＜0.001;显性遗传模型（CG＋ GGvs.CC）：OR=1.31,95％CI：1.17～ 1.46,P＜0.001;隐性遗传模型（GGvs.CC＋GC）：OR=2.26,95％CI：1.76～ 2.90,P＜0.001];亚组分析显示,亚洲以及高加索人群PNPLA3基因rs738409位点多态性与非酒精性脂肪肝易感性有关联.敏感性分析显示Meta分析结果稳定.结论 PNPLA3基因I148M多态性与非酒精性脂肪肝易感性明显相关.

固醇调节元件结合蛋白1c激活大鼠Patatin样磷酯酶结构域蛋白3基因转录

目的探讨固醇调节元件结合蛋白1c（SREBP-1e）对Patatin样磷酯酶结构域蛋白3（PNPLA3）基因的转录调控作用。方法构建7周龄雄性体重匹配的禁食（24h）以及禁食后再喂食（48h）SD大鼠（自由饮食组3只，饥饿组3只，再喂食组4只）和高脂及小剂量链脲佐菌素诱导的2型糖尿病sD大鼠（正常对照组5只，2型糖尿病组6只）。用逆转录聚合酶链反应（RT—PCR）和Western blotting法检测各组大鼠肝脏组织中SREBP一1c和PAPM3的表达水平。将大鼠PⅣP翻3启动子5’端上游-1000bp序列分成3段，分别构建荧光素酶报告载体（R—PⅣPM3．1、R—PM似3—2、R—PNPL43—3），转染人正常肝细胞株L02，比较3个载体基础荧光素酶活性以及SREBP-1e过表达诱导的荧光素酶活性。分析上述实验中荧光素酶活性最高的PNPLA3启动子片段可能的SREBP-1c结合位点（SRE），分别构建野生型和SRE突变型报告载体，比较两个载体荧光素酶活性。多组定量资料比较用方差分析，两组定量资料比较用t检验。结果与自由饮食组相比，饥饿组大鼠肝脏SREBP—lc、PNPLA3和脂肪酸合成酶FAS基因表达均下降，再喂食组三者表达显著升高，差异均有统计学意义（F=114．14，334．11，754．20，均P〈0．05）。与正常对照组相比，2型糖尿病组SREBP-1e、PNPLA3基因（t=-18．39，-30．07，均P〈0．05）及蛋白表达（t=4．58，6．81，均P〈0．05）均显著增高。R—PNPLA3-1报告载体基础荧光素酶活性较对照升高51．13倍（t=-28．93，P〈0．05），R一删PM3—2和R—PNPLA3—3无基础荧光素酶活性；在L02细胞中，转染SREBP-1c表达质粒的R—PⅣPL43—1组荧光比值较转染空质粒的组升高2．63倍（t=-7．64，P〈0．05），而R—PⅣPM3．2组及R—PNPLA3—3组转染SREBP-1e表达质粒荧光比值较转染空质粒组均无变化；PNPLA3启动子-100～-911）p存在SRE，SRE突变的报告载体（MUT—R—PNPLA３—1）荧光比值较野生型（R—PNPLA３-1）降低40．80％（t=4．99，P〈0．05）。结论SREBP-1c通过PNPLA３基因启动子－100～－91bp激活大鼠PNPLA3基因转录。

Non-alcoholic fatty liver disease-the heart of the matter

Non-alcoholic fatty liver disease(NAFLD) is one of the most common forms of chronic liver disease in the Western world. There is a close association with the metabolic syndrome and NAFLD is considered to be the hepatic manifestation of the metabolic syndrome. The components of the metabolic syndrome include hypertension,obesity and insulin resistance which are well established cardiovascular risk factors. The mortality rate of NAFLD patients from myocardial infarction is higher than that in the general United States population and there is also an increased risk of nonfatal cardiovascular events. This article reviews the cardiovascular complications associated with NAFLD. Inorder to provide comprehensive care of NAFLD patients,physicians need to be aware of,and search for,the cardiac morbidity associated with NAFLD.

Hepatocellular carcinoma in nonalcoholic fatty liver: Role of environmental and genetic factors

Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoholic fatty liver disease(NAFLD) associated with obesity, insulin resistance, and type 2 diabetes, is an increasingly recognized trigger, especially in developed countries. Older age, severity of insulin resistance and diabetes, and iron overload have been reported to predispose to HCC in this context. Remarkably, HCCs have been reported in non-cirrhotic livers in a higher proportion of cases in NAFLD patients than in other etiologies. Inherited factors have also been implicated to explain the different individual susceptibility to develop HCC, and their role seems magnified in fatty liver, where only a minority of affected subjects progresses to cancer. In particular, the common I148 M variant of the PNPLA3 gene influencing hepatic lipid metabolism influences HCC risk independently of its effect on the progression of liver fibrosis. Recently, rare loss-of-function mutations in Apolipoprotein B resulting in very low density lipoproteins hepatic retention and in Telomerase reverse transcriptase influencing cellular senescence have also been linked to HCC in NAFLD. Indeed, hepatic stellate cells senescence has been suggested to bridge tissue aging with alterations of the intestinal microbiota in the pathogenesis of obesity-related HCC. A deeper understanding of the mechanisms mediating hepatic carcinogenesis during insulin resistance, and the identification of its genetic determinants will hopefully provide new diagnostic and therapeutic tools.