This review intends to uncover how information from large-scale genetic profiling(whole genome sequencing, and whole exome sequencing) of nonalcoholic fatty liver disease(NAFLD), as well as information from circulatin...This review intends to uncover how information from large-scale genetic profiling(whole genome sequencing, and whole exome sequencing) of nonalcoholic fatty liver disease(NAFLD), as well as information from circulating transcriptomics(cell-free mi RNAs) and metabolomics, contributes to the understanding of NAFLD pathogenesis. A further aim is to address the question of whether OMICs information is ready to be implemented in the clinics. The available evidence suggests that any new knowledge pertaining to molecular signatures associated with NAFLD and nonalcoholic steatohepatitis should be promptly translated into the clinical setting. Nevertheless, rigorous steps that must include validation and replication are mandatory before utilizing OMICs biomarkers in diagnostics to identify patients at risk of advanced disease, including liver cancer.展开更多
For several decades,serum levels of alanine(ALT) and aspartate(AST) aminotransferases have been regarded as markers of liver injury,including a wide range of etiologies from viral hepatitis to fatty liver.The increasi...For several decades,serum levels of alanine(ALT) and aspartate(AST) aminotransferases have been regarded as markers of liver injury,including a wide range of etiologies from viral hepatitis to fatty liver.The increasing worldwide prevalence of metabolic syndrome and cardiovascular disease revealed that transaminases are strong predictors of type 2 diabetes,coronary heart disease,atherothrombotic risk profile,and overall risk of metabolic disease.Therefore,it is plausible to suggest that aminotransferases are surrogate biomarkers of "liver metabolic functioning" beyond the classical concept of liver cellular damage,as their enzymatic activity might actually reflect key aspects of the physiology and pathophysiology of the liver function.In this study,we summarize the background information and recent findings on the biological role of ALT and AST,and review the knowledge gained from the application of genome-wide approaches and "omics" technologies that uncovered new concepts on the role of aminotransferases in human diseases and systemic regulation of metabolic functions.Prediction of biomolecular interactions between the candidate genes recently discovered to be associated with plasma concentrations of liver enzymes showed interesting interconnectivity nodes,which suggest that regulation of aminotransferase activity is a complex and highly regulated trait.Finally,links between aminotransferase genes and metabolites are explored to understand the genetic contributions to the metabolic diversity.展开更多
Genome-wide and candidate gene association studies have identified several variants that predispose indi- viduals to developing nonalcoholic fatty liver disease （NAFLD）. However, the gene that has been consis- tentl...Genome-wide and candidate gene association studies have identified several variants that predispose indi- viduals to developing nonalcoholic fatty liver disease （NAFLD）. However, the gene that has been consis- tently involved in the genetic susceptibility of NAFLD in humans is patatin-like phospholipase domain contain- ing 3 （PNPLA3, also known as adiponutrin）. A nonsyn- onymous single nucleotide polymorphism in PNPLA3 （rs738409 C/G, a coding variant that encodes an amino acid substitution I148M） is significantly associated with fatty liver and histological disease severity, not only in adults but also in children. Nevertheless, how PNPLA3 influences the biology of fatty liver disease is still an open question. A recent article describes new aspects about PNPLA3 gene/protein function and suggests that the I148M variant promotes hepatic lipid synthesis due to a gain of function. We revise here the published data about the role of the I148M variant in lipogen- esis/lipolysis, and suggest putative areas of future research. For instance we explored in silico whether the rs738409 C or G alleles have the ability to modify miRNA binding sites and miRNA gene regulation, and we found that prediction of PNPLA3 target miRNAs shows two miRNAs potentially interacting in the 3＇ UTR region （hsa-miR-769-3p and hsa-miR-516a-3p）. In addition, interesting unanswered questions remain to be explored. For example, PNPLA3 lies between two CCCTC-binding factor-bound sites that could be tested for insulator activity, and an intronic histone 3 lysine 4 trimethylation peak predicts an enhancer element, cor- roborated by the DNase I hypersensitivity site peak. Finally, an interaction between PNPLA3 and glycerol- 3-phosphate acyltransferase 2 is suggested by data miming.展开更多
AIM： TO evaluate the safety and efficacy of chronic administration of Iosartan on hepatic fibrosis in chronic hepatitis C patients.METHODS： Fourteen patients with chronic hepatitis C non-responders （n = 10）, with ...AIM： TO evaluate the safety and efficacy of chronic administration of Iosartan on hepatic fibrosis in chronic hepatitis C patients.METHODS： Fourteen patients with chronic hepatitis C non-responders （n = 10）, with contraindications （n = 2） or lack of compliance （n = 2） to interferon plus ribavirin therapy and liver fibrosis were enrolled. Liver and renal function test, clinical evaluation, and liver biopsies were performed at baseline and after Iosartan administration at a dose of 50 mg/d during the 6 mo. The control group composed of nine patients with the same inclusion criteria and paired liver biopsies （interval 6-14 mo）. Histological activity index （HAI） with fibrosis stage was assessed under blind conditions by means of Ishak＇s score. Subendothelial fibrosis was evaluated by digital image analyses.RESULTS： The changes in the fibrosis stage were significantly different between Iosartan group （decrease of 0.5±1.3） and controls （increase of 0.89±1.27; P〈0.03）. In the treated patients, a decrease in fibrosis stage was observed in 7/14 patients vs 1/9 control patients （P〈0.04）. A decrease in sub-endothelial fibrosis was observed in the Iosartan group. No differences were found in HAI after Iosartan administration. Acute and chronic decreases in systolic arterial pressures （P〈0.05） were observed after the Iosartan administration, without changes in mean arterial pressure or renal function.CONCLUSION： Chronic AT-Ⅱ type 1 receptor （AT1R） blockade may reduce liver fibrosis in patients with chronic hepatitis C.展开更多
To investigate the role of gene variants and derived haplotypes of the CLOCK transcription factor in nonalcoholic fatty liver disease （NAFID） and their relation with the disease severity.METHODS： A total of 136 pat...To investigate the role of gene variants and derived haplotypes of the CLOCK transcription factor in nonalcoholic fatty liver disease （NAFID） and their relation with the disease severity.METHODS： A total of 136 patients with NAFLD and 64 healthy individuals were studied. Liver biopsy was performed in 91 patients. Six tag SNPs showing a minor allele frequency 〉 10% （rs1554483 C/G; rs11932595 A/G; rs4580704 C/G; rs6843722 A/C; rs6850524 C/G and rs4864548 A/G） encompassing 117 kb of chromosome 4 and representing 115 polymorphic sites （P 〉 0.8） were genotyped. RESULTS： rs11932595 and rs6843722 showed significant associations with NAFLD （empiric P = 0.0449 and 0.023, respectively）. A significant association was also observed between clinical or histologic spectrum of NAFLD and rs1554483 （empiric P = 0.0399）, rs6843722 （empiric P = 0.0229） and rs6850524 （empiric P = 0.00899） and between fibrosis score and rs1554483 （empiric P = 0.02697）, rs6843722 （empiric P = 0.01898） and rs4864548 （empiric P = 0.02697）. Test of haplotypic association showed that CLOCK gene variant haplotypes frequencies in NAFLD individuals significantly differed from those in controls （empiric P = 0.0097）.CONCLUSION： Our study suggests a potential role of the CLOCK polymorphisms and their haplotypes insusceptibility to NAFLD and disease severity.展开更多
The pathogenesis of intrahepatic cholestasis of pregnancy (ICP), a disorder that adversely affects maternal wellbeing and fetal outcome, is unclear. However, multiple factors probably interact along with a genetic pre...The pathogenesis of intrahepatic cholestasis of pregnancy (ICP), a disorder that adversely affects maternal wellbeing and fetal outcome, is unclear. However, multiple factors probably interact along with a genetic predisposition. We would like to add some comments on a paper recently published concerning the role of ABCB11 and ABCC2 polymorphisms in both ICP and contraceptive-induced cholestasis, especially in the light of our recently published findings about a positive association between ICP and ABCC2 common variants.展开更多
AIM: To analyze the molecular evolution of different viral genomic regions of HCV in an acute HCV infected patient chronically infected with HIV through a 42-month follow-up.METHODS: Serum samples of a chronically HIV...AIM: To analyze the molecular evolution of different viral genomic regions of HCV in an acute HCV infected patient chronically infected with HIV through a 42-month follow-up.METHODS: Serum samples of a chronically HIV infected patient that seroconverted to anti HCV antibodies were sequenced, from the event of superinfection through a period of 17 months and in a late sample (42nd month). Hypervariable genomic regions of HIV (V3 loop of the gp120) and HCV (HVR-1 on the E2 glycoprotein gene) were studied. In order to analyze genomic regions involved in different biological functions and with the cellular immune response, HCV core and NS5A were also chosen to be sequenced. Amplification of the different regions was done by RT-PCR and directly sequenced. Confirmation of sequences was done on reamplified material. Nucleotide sequences of the different time points were aligned with CLUSTAL W 1.5, and the corresponding amino acid ones were deduced.RESULTS: Hypervariable genomic regions of both viruses (HVR1 and gp120 V3 loop) presented several nonsynonymous changes but, while in the gp120 V3 loop mutations were detected in the sample obtained right after HCV superinfection and maintained throughout, they occurred following a sequential and cumulative pattern in the HVR1. In the NS5A region of HCV, two amino acid changes were detected during the follow-up period, whereas the core region presented several amino acid replacements, once the HCV chronic infection had been established.CONCLUSION: During the HIV-HCV superinfection, each genomic region analyzed shows a different evolutionary pattem.Most of the nucleotide substitutions observed are nonsynonymous and clustered in previously described epitopes,thus suggesting an immune-driven evolutionary process.展开更多
Genome-wide association studies of complex diseases,including nonalcoholic fatty liver disease(NAFLD),have demonstrated that a large number of variants are implicated in the susceptibility of multiple traits—a phenom...Genome-wide association studies of complex diseases,including nonalcoholic fatty liver disease(NAFLD),have demonstrated that a large number of variants are implicated in the susceptibility of multiple traits—a phenomenon known as pleiotropy that is increasingly being explored through phenome-wide association studies.We focused on the analysis of pleiotropy within variants associated with hematologic traits and NAFLD.We used information retrieved from large public National Health and Nutrition Examination Surveys,Genome-wide association studies,and phenome-wide association studies based on the general population and explored whether variants associated with NAFLD also present associations with blood cell-related traits.Next,we applied systems biology approaches to assess the potential biological connection/s between genes that predispose affected individuals to NAFLD and nonalcoholic steatohepatitis,and genes that modulate hematological-related traits—specifically platelet count.We reasoned that this analysis would allow the identification of potential molecular mediators that link NAFLD with platelets.Genes associated with platelet count are most highly expressed in the liver,followed by the pancreas,heart,and muscle.Conversely,genes associated with NAFLD presented high expression levels in the brain,lung,spleen,and colon.Functional mapping,gene prioritization,and functional analysis of the most significant loci(P<1×10-8)revealed that loci involved in the genetic modulation of platelet count presented significant enrichment in metabolic and energy balance pathways.In conclusion,variants in genes influencing NAFLD exhibit pleiotropic associations with hematologic traits,particularly platelet count.Likewise,significant enrichment of related genes with variants influencing platelet traits was noted in metabolic-related pathways.Hence,this approach yields novel mechanistic insights into NAFLD pathogenesis.展开更多
Although new research technologies are constantly used to look either for genes or biomarkers in the prediction of metabolic syndrome(MS),the pathogenesis and pathophysiology of this complex disease remains a major ch...Although new research technologies are constantly used to look either for genes or biomarkers in the prediction of metabolic syndrome(MS),the pathogenesis and pathophysiology of this complex disease remains a major challenge.Interestingly,Cheng et al recently investigated possible pathways underlying MS by high-throughput metabolite profiling in two large and well characterized community-based cohorts.The authors explored by liquid chromatography and mass spectrometry the plasma concentrations of 45 distinct metabolites and examined their relation to cardiometabolic risk,and observed that metabolic risk factors such as obesity,insulin resistance(IR),high blood pressure,and dyslipidemia were associated with several metabolites,including branched-chain amino acids,other hydrophobic amino acids,tryptophan breakdown products,and nucleotide metabolites.In addition,the authors found a significant association of IR traits with glutamine,glutamate and the glutamineto-glutamate ratio.These data provide new insight into the pathogenesis of MS-associated phenotypes and introduce a crucial role of glutamine-cycling pathway as prominently involved in the development of metabolic risk.We consider that the hypothesis about the role of abnormal glutamate metabolism in the pathogenesis of the MS is certainly challenging and suggests the critical role of the liver in the global metabolic modulation as glutamate metabolism is linked with aminotransferase reactions.We discuss here the critical role of the "liver metabolism" in the pathogenesis of the MS and IR,and postulate that before fatty liver develops,abnormal levels of liver enzymes,such as alanine and aspartate aminotransferases might reflect high levels of hepatic transamination of amino acids in the liver.展开更多
Nonalcoholic fatty liver disease(NAFLD) is a complex disorder that has evolved in recent years as the leading global cause of chronic liver damage. The main obstacle to better disease management pertains to the lack o...Nonalcoholic fatty liver disease(NAFLD) is a complex disorder that has evolved in recent years as the leading global cause of chronic liver damage. The main obstacle to better disease management pertains to the lack of approved pharmacological interventions for the treatment of nonalcoholic steatohepatitis(NASH) and NASH-fibrosis-the severe histological forms. Over the past decade,tremendous advances have been made in NAFLD research, resulting in the discovery of disease mechanisms and novel therapeutic targets. Hence, a large number of pharmacological agents are currently being tested for safety and efficacy. These drugs are in the initial pharmacological phases(phase 1 and 2),which involve testing tolerability, therapeutic action, and pharmacological issues.It is thus reasonable to assume that the next generation of NASH drugs will not be available for clinical use for foreseeable future. The expected delay can be mitigated by drug repurposing or repositioning, which essentially relies on identifying and developing new uses for existing drugs. Here, we propose a drug candidate selection method based on the integration of molecular pathways of disease pathogenesis into network analysis tools that use OMICs data as well as multiples sources, including text mining from the medical literature.展开更多
Background:With the rising global prevalence of fatty liver disease related to metabolic dysfunction,the association of this common liver condition with chronic kidney disease(CKD)has become increasingly evident.In 20...Background:With the rising global prevalence of fatty liver disease related to metabolic dysfunction,the association of this common liver condition with chronic kidney disease(CKD)has become increasingly evident.In 2020,the more inclusive term metabolic dysfunction-associated fatty liver disease(MAFLD)was proposed to replace the term non-alcoholic fatty liver disease(NAFLD).The observed association between MAFLD and CKD and our understanding that CKD can be a consequence of underlying metabolic dysfunction support the notion that individuals with MAFLD are at higher risk of having and developing CKD compared with those without MAFLD.However,to date,there is no appropriate guidance on CKD in individuals with MAFLD.Furthermore,there has been little attention paid to the link between MAFLD and CKD in the Nephrology community.Methods and Results:Using a Delphi-based approach,a multidisciplinary panel of 50 international experts from 26 countries reached a consensus on some of the open research questions regarding the link between MAFLD and CKD.Conclusions:This Delphi-based consensus statement provided guidance on the epidemiology,mechanisms,management and treatment of MAFLD and CKD,as well as the relationship between the severity of MAFLD and risk of CKD,which establish a framework for the early prevention and management of these two common and interconnected diseases.展开更多
Nonalcoholic fatty liver disease(NAFLD)pathogenesis is explained by the complex relationship among diet and lifestyle-predisposing factors,the genetic variance of the nuclear and mitochondrial genome,associated phenot...Nonalcoholic fatty liver disease(NAFLD)pathogenesis is explained by the complex relationship among diet and lifestyle-predisposing factors,the genetic variance of the nuclear and mitochondrial genome,associated phenotypic traits,and the yet not fully explored interactions with epigenetic and other environmental factors,including the microbiome.Despite the wealth of knowledge gained from molecular and genome-wide investigations in patients with NAFLD,the precise mechanisms that explain the variability of the histological phenotypes are not fully understood.Earlier studies of the gut microbiota in patients with NAFLD and nonalcoholic steatohepatitis(NASH)provided clues on the role of the fecal microbiome in the disease pathogenesis.Nevertheless,the composition of the gut microbiota does not fully explain tissue-specific mechanisms associated with the degree of disease severity,including liver inflammation,ballooning of hepatocytes,and fibrosis.The liver acts as a key filtration system of the whole body by receiving blood from the hepatic artery and the portal vein.Therefore,not only microbes would become entrapped in the complex liver anatomy but,more importantly,bacterial derived products that are likely to be potentially powerful stimuli for initiating the inflammatory response.Hence,the study of liver tissue microbiota offers the opportunity of changing the paradigm of host-NAFLD-microbial interactions from a“gut-centric”to a“liver-centric”approach.Here,we highlight the evidence on the role of liver tissue bacterial DNA in the biology of NAFLD and NASH.Besides,we provide evidence of metagenomic findings that can serve as the seed of further hypothesis-raising studies as well as can be leveraged to discover novel therapeutic targets.展开更多
Nonalcoholic fatty liver disease(NAFLD)is regarded as the most frequent cause of chronic liver damage(1,2).The natural history of the disease presents a complex scenario of potential progression into severe clinical o...Nonalcoholic fatty liver disease(NAFLD)is regarded as the most frequent cause of chronic liver damage(1,2).The natural history of the disease presents a complex scenario of potential progression into severe clinical outcomes,including nonalcoholic steatohepatitis(NASH),NASH-fibrosis,cirrhosis,and hepatocellular carcinoma(1,2).In addition,NAFLD is closely associated with comorbidities of the metabolic syndrome(MetS),including type 2 diabetes,obesity,arterial hypertension,and dyslipidemia,which together aggravate the morbidity and mortality associated with the disease.展开更多
Nonalcoholic steatohepatitis (NASH)—the severe histological form of nonalcoholic fatty liver disease (NAFLD)—is regarded as a major health problem worldwide (1,2). The disease can progress to liver cirrhosis and eve...Nonalcoholic steatohepatitis (NASH)—the severe histological form of nonalcoholic fatty liver disease (NAFLD)—is regarded as a major health problem worldwide (1,2). The disease can progress to liver cirrhosis and eventually to hepatocellular carcinoma (1,3). Treatment of NASH and NASH-fibrosis is thus increasingly being given priority in the clinical field. Yet, these efforts face challenges not only related to the design and validation of novel pharmacological agents, but also to the need to optimize treatment options as well as improve access to therapies. In fact, while many drugs are currently being tested for safety and efifcacy, only a few approved options for the treatment of NASH presently exist (4,5). It is thus expected that, in the near future, emphasis will be given to selecting the right drug for treating NASH patients from a wide spectrum of treatment choices. Hence, identiifcation of early predictors of treatment response represents an unmet and relevant need.展开更多
基金Supported by Agencia Nacional de Promoción Científicay Tecnológica,No.PICT 2014-0432,No.PICT 2014-1816 and No.PICT 2015-0551
文摘This review intends to uncover how information from large-scale genetic profiling(whole genome sequencing, and whole exome sequencing) of nonalcoholic fatty liver disease(NAFLD), as well as information from circulating transcriptomics(cell-free mi RNAs) and metabolomics, contributes to the understanding of NAFLD pathogenesis. A further aim is to address the question of whether OMICs information is ready to be implemented in the clinics. The available evidence suggests that any new knowledge pertaining to molecular signatures associated with NAFLD and nonalcoholic steatohepatitis should be promptly translated into the clinical setting. Nevertheless, rigorous steps that must include validation and replication are mandatory before utilizing OMICs biomarkers in diagnostics to identify patients at risk of advanced disease, including liver cancer.
基金Supported by(in part)Grants PICT 2010-0441 and PICT 2012-0159(Agencia Nacional de Promoción Científica y Tecnológica)and UBACYT CM04(Universidad de Buenos Aires)
文摘For several decades,serum levels of alanine(ALT) and aspartate(AST) aminotransferases have been regarded as markers of liver injury,including a wide range of etiologies from viral hepatitis to fatty liver.The increasing worldwide prevalence of metabolic syndrome and cardiovascular disease revealed that transaminases are strong predictors of type 2 diabetes,coronary heart disease,atherothrombotic risk profile,and overall risk of metabolic disease.Therefore,it is plausible to suggest that aminotransferases are surrogate biomarkers of "liver metabolic functioning" beyond the classical concept of liver cellular damage,as their enzymatic activity might actually reflect key aspects of the physiology and pathophysiology of the liver function.In this study,we summarize the background information and recent findings on the biological role of ALT and AST,and review the knowledge gained from the application of genome-wide approaches and "omics" technologies that uncovered new concepts on the role of aminotransferases in human diseases and systemic regulation of metabolic functions.Prediction of biomolecular interactions between the candidate genes recently discovered to be associated with plasma concentrations of liver enzymes showed interesting interconnectivity nodes,which suggest that regulation of aminotransferase activity is a complex and highly regulated trait.Finally,links between aminotransferase genes and metabolites are explored to understand the genetic contributions to the metabolic diversity.
基金Supported by Grants PICT 2008-1521 and PICT 2010 0441,from National Agency for Science and TechnologyUBACYT CM04,from Universidad de Buenos AiresSookoian S and Pirola CJ belong to National Council of Scientific and Technical Research
文摘Genome-wide and candidate gene association studies have identified several variants that predispose indi- viduals to developing nonalcoholic fatty liver disease （NAFLD）. However, the gene that has been consis- tently involved in the genetic susceptibility of NAFLD in humans is patatin-like phospholipase domain contain- ing 3 （PNPLA3, also known as adiponutrin）. A nonsyn- onymous single nucleotide polymorphism in PNPLA3 （rs738409 C/G, a coding variant that encodes an amino acid substitution I148M） is significantly associated with fatty liver and histological disease severity, not only in adults but also in children. Nevertheless, how PNPLA3 influences the biology of fatty liver disease is still an open question. A recent article describes new aspects about PNPLA3 gene/protein function and suggests that the I148M variant promotes hepatic lipid synthesis due to a gain of function. We revise here the published data about the role of the I148M variant in lipogen- esis/lipolysis, and suggest putative areas of future research. For instance we explored in silico whether the rs738409 C or G alleles have the ability to modify miRNA binding sites and miRNA gene regulation, and we found that prediction of PNPLA3 target miRNAs shows two miRNAs potentially interacting in the 3＇ UTR region （hsa-miR-769-3p and hsa-miR-516a-3p）. In addition, interesting unanswered questions remain to be explored. For example, PNPLA3 lies between two CCCTC-binding factor-bound sites that could be tested for insulator activity, and an intronic histone 3 lysine 4 trimethylation peak predicts an enhancer element, cor- roborated by the DNase I hypersensitivity site peak. Finally, an interaction between PNPLA3 and glycerol- 3-phosphate acyltransferase 2 is suggested by data miming.
文摘AIM： TO evaluate the safety and efficacy of chronic administration of Iosartan on hepatic fibrosis in chronic hepatitis C patients.METHODS： Fourteen patients with chronic hepatitis C non-responders （n = 10）, with contraindications （n = 2） or lack of compliance （n = 2） to interferon plus ribavirin therapy and liver fibrosis were enrolled. Liver and renal function test, clinical evaluation, and liver biopsies were performed at baseline and after Iosartan administration at a dose of 50 mg/d during the 6 mo. The control group composed of nine patients with the same inclusion criteria and paired liver biopsies （interval 6-14 mo）. Histological activity index （HAI） with fibrosis stage was assessed under blind conditions by means of Ishak＇s score. Subendothelial fibrosis was evaluated by digital image analyses.RESULTS： The changes in the fibrosis stage were significantly different between Iosartan group （decrease of 0.5±1.3） and controls （increase of 0.89±1.27; P〈0.03）. In the treated patients, a decrease in fibrosis stage was observed in 7/14 patients vs 1/9 control patients （P〈0.04）. A decrease in sub-endothelial fibrosis was observed in the Iosartan group. No differences were found in HAI after Iosartan administration. Acute and chronic decreases in systolic arterial pressures （P〈0.05） were observed after the Iosartan administration, without changes in mean arterial pressure or renal function.CONCLUSION： Chronic AT-Ⅱ type 1 receptor （AT1R） blockade may reduce liver fibrosis in patients with chronic hepatitis C.
基金Supported by Grant B119 (Universidad de Buenos Aires), PICT 25920 (Agencia Nacional de Promoción Científi ca y Tecnológica) and PIP 5195 (Consejo Nacional de Investigaciones Científicas y Técnicas). SS, CG and CJP belong to Consejo Nacional de Investigaciones Científi cas y Técnicas
文摘To investigate the role of gene variants and derived haplotypes of the CLOCK transcription factor in nonalcoholic fatty liver disease （NAFID） and their relation with the disease severity.METHODS： A total of 136 patients with NAFLD and 64 healthy individuals were studied. Liver biopsy was performed in 91 patients. Six tag SNPs showing a minor allele frequency 〉 10% （rs1554483 C/G; rs11932595 A/G; rs4580704 C/G; rs6843722 A/C; rs6850524 C/G and rs4864548 A/G） encompassing 117 kb of chromosome 4 and representing 115 polymorphic sites （P 〉 0.8） were genotyped. RESULTS： rs11932595 and rs6843722 showed significant associations with NAFLD （empiric P = 0.0449 and 0.023, respectively）. A significant association was also observed between clinical or histologic spectrum of NAFLD and rs1554483 （empiric P = 0.0399）, rs6843722 （empiric P = 0.0229） and rs6850524 （empiric P = 0.00899） and between fibrosis score and rs1554483 （empiric P = 0.02697）, rs6843722 （empiric P = 0.01898） and rs4864548 （empiric P = 0.02697）. Test of haplotypic association showed that CLOCK gene variant haplotypes frequencies in NAFLD individuals significantly differed from those in controls （empiric P = 0.0097）.CONCLUSION： Our study suggests a potential role of the CLOCK polymorphisms and their haplotypes insusceptibility to NAFLD and disease severity.
文摘The pathogenesis of intrahepatic cholestasis of pregnancy (ICP), a disorder that adversely affects maternal wellbeing and fetal outcome, is unclear. However, multiple factors probably interact along with a genetic predisposition. We would like to add some comments on a paper recently published concerning the role of ABCB11 and ABCC2 polymorphisms in both ICP and contraceptive-induced cholestasis, especially in the light of our recently published findings about a positive association between ICP and ABCC2 common variants.
基金the Universidad de Buenos Aires(SECyT-UBA,TB14)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET,PIP723)+1 种基金Agencia Nacional de Promoción Científica y Tecnológica(ANPCyT,PICT 01610)Ministerio de Salud Pǘblica de la Nación(Beca Carrillo-Oativia)
文摘AIM: To analyze the molecular evolution of different viral genomic regions of HCV in an acute HCV infected patient chronically infected with HIV through a 42-month follow-up.METHODS: Serum samples of a chronically HIV infected patient that seroconverted to anti HCV antibodies were sequenced, from the event of superinfection through a period of 17 months and in a late sample (42nd month). Hypervariable genomic regions of HIV (V3 loop of the gp120) and HCV (HVR-1 on the E2 glycoprotein gene) were studied. In order to analyze genomic regions involved in different biological functions and with the cellular immune response, HCV core and NS5A were also chosen to be sequenced. Amplification of the different regions was done by RT-PCR and directly sequenced. Confirmation of sequences was done on reamplified material. Nucleotide sequences of the different time points were aligned with CLUSTAL W 1.5, and the corresponding amino acid ones were deduced.RESULTS: Hypervariable genomic regions of both viruses (HVR1 and gp120 V3 loop) presented several nonsynonymous changes but, while in the gp120 V3 loop mutations were detected in the sample obtained right after HCV superinfection and maintained throughout, they occurred following a sequential and cumulative pattern in the HVR1. In the NS5A region of HCV, two amino acid changes were detected during the follow-up period, whereas the core region presented several amino acid replacements, once the HCV chronic infection had been established.CONCLUSION: During the HIV-HCV superinfection, each genomic region analyzed shows a different evolutionary pattem.Most of the nucleotide substitutions observed are nonsynonymous and clustered in previously described epitopes,thus suggesting an immune-driven evolutionary process.
文摘Genome-wide association studies of complex diseases,including nonalcoholic fatty liver disease(NAFLD),have demonstrated that a large number of variants are implicated in the susceptibility of multiple traits—a phenomenon known as pleiotropy that is increasingly being explored through phenome-wide association studies.We focused on the analysis of pleiotropy within variants associated with hematologic traits and NAFLD.We used information retrieved from large public National Health and Nutrition Examination Surveys,Genome-wide association studies,and phenome-wide association studies based on the general population and explored whether variants associated with NAFLD also present associations with blood cell-related traits.Next,we applied systems biology approaches to assess the potential biological connection/s between genes that predispose affected individuals to NAFLD and nonalcoholic steatohepatitis,and genes that modulate hematological-related traits—specifically platelet count.We reasoned that this analysis would allow the identification of potential molecular mediators that link NAFLD with platelets.Genes associated with platelet count are most highly expressed in the liver,followed by the pancreas,heart,and muscle.Conversely,genes associated with NAFLD presented high expression levels in the brain,lung,spleen,and colon.Functional mapping,gene prioritization,and functional analysis of the most significant loci(P<1×10-8)revealed that loci involved in the genetic modulation of platelet count presented significant enrichment in metabolic and energy balance pathways.In conclusion,variants in genes influencing NAFLD exhibit pleiotropic associations with hematologic traits,particularly platelet count.Likewise,significant enrichment of related genes with variants influencing platelet traits was noted in metabolic-related pathways.Hence,this approach yields novel mechanistic insights into NAFLD pathogenesis.
基金Supported by Grants PICT 2008-1521 and 2010-0441,from Agencia Nacional de Promoción Científica y TecnológicaUBACYT CM04,from Universidad de Buenos Aires
文摘Although new research technologies are constantly used to look either for genes or biomarkers in the prediction of metabolic syndrome(MS),the pathogenesis and pathophysiology of this complex disease remains a major challenge.Interestingly,Cheng et al recently investigated possible pathways underlying MS by high-throughput metabolite profiling in two large and well characterized community-based cohorts.The authors explored by liquid chromatography and mass spectrometry the plasma concentrations of 45 distinct metabolites and examined their relation to cardiometabolic risk,and observed that metabolic risk factors such as obesity,insulin resistance(IR),high blood pressure,and dyslipidemia were associated with several metabolites,including branched-chain amino acids,other hydrophobic amino acids,tryptophan breakdown products,and nucleotide metabolites.In addition,the authors found a significant association of IR traits with glutamine,glutamate and the glutamineto-glutamate ratio.These data provide new insight into the pathogenesis of MS-associated phenotypes and introduce a crucial role of glutamine-cycling pathway as prominently involved in the development of metabolic risk.We consider that the hypothesis about the role of abnormal glutamate metabolism in the pathogenesis of the MS is certainly challenging and suggests the critical role of the liver in the global metabolic modulation as glutamate metabolism is linked with aminotransferase reactions.We discuss here the critical role of the "liver metabolism" in the pathogenesis of the MS and IR,and postulate that before fatty liver develops,abnormal levels of liver enzymes,such as alanine and aspartate aminotransferases might reflect high levels of hepatic transamination of amino acids in the liver.
文摘Nonalcoholic fatty liver disease(NAFLD) is a complex disorder that has evolved in recent years as the leading global cause of chronic liver damage. The main obstacle to better disease management pertains to the lack of approved pharmacological interventions for the treatment of nonalcoholic steatohepatitis(NASH) and NASH-fibrosis-the severe histological forms. Over the past decade,tremendous advances have been made in NAFLD research, resulting in the discovery of disease mechanisms and novel therapeutic targets. Hence, a large number of pharmacological agents are currently being tested for safety and efficacy. These drugs are in the initial pharmacological phases(phase 1 and 2),which involve testing tolerability, therapeutic action, and pharmacological issues.It is thus reasonable to assume that the next generation of NASH drugs will not be available for clinical use for foreseeable future. The expected delay can be mitigated by drug repurposing or repositioning, which essentially relies on identifying and developing new uses for existing drugs. Here, we propose a drug candidate selection method based on the integration of molecular pathways of disease pathogenesis into network analysis tools that use OMICs data as well as multiples sources, including text mining from the medical literature.
文摘Background:With the rising global prevalence of fatty liver disease related to metabolic dysfunction,the association of this common liver condition with chronic kidney disease(CKD)has become increasingly evident.In 2020,the more inclusive term metabolic dysfunction-associated fatty liver disease(MAFLD)was proposed to replace the term non-alcoholic fatty liver disease(NAFLD).The observed association between MAFLD and CKD and our understanding that CKD can be a consequence of underlying metabolic dysfunction support the notion that individuals with MAFLD are at higher risk of having and developing CKD compared with those without MAFLD.However,to date,there is no appropriate guidance on CKD in individuals with MAFLD.Furthermore,there has been little attention paid to the link between MAFLD and CKD in the Nephrology community.Methods and Results:Using a Delphi-based approach,a multidisciplinary panel of 50 international experts from 26 countries reached a consensus on some of the open research questions regarding the link between MAFLD and CKD.Conclusions:This Delphi-based consensus statement provided guidance on the epidemiology,mechanisms,management and treatment of MAFLD and CKD,as well as the relationship between the severity of MAFLD and risk of CKD,which establish a framework for the early prevention and management of these two common and interconnected diseases.
基金This study was partially supported by grants PID-C2012-0061,PICT 2014-0432,PICT 2014-1816,PICT 2015-0551PICT 2016-0135(Agencia Nacional de Promoción Científica y Tecnológica,FONCyT),CONICET Proyectos Unidades Ejecutoras 2017,PUE 0055.
文摘Nonalcoholic fatty liver disease(NAFLD)pathogenesis is explained by the complex relationship among diet and lifestyle-predisposing factors,the genetic variance of the nuclear and mitochondrial genome,associated phenotypic traits,and the yet not fully explored interactions with epigenetic and other environmental factors,including the microbiome.Despite the wealth of knowledge gained from molecular and genome-wide investigations in patients with NAFLD,the precise mechanisms that explain the variability of the histological phenotypes are not fully understood.Earlier studies of the gut microbiota in patients with NAFLD and nonalcoholic steatohepatitis(NASH)provided clues on the role of the fecal microbiome in the disease pathogenesis.Nevertheless,the composition of the gut microbiota does not fully explain tissue-specific mechanisms associated with the degree of disease severity,including liver inflammation,ballooning of hepatocytes,and fibrosis.The liver acts as a key filtration system of the whole body by receiving blood from the hepatic artery and the portal vein.Therefore,not only microbes would become entrapped in the complex liver anatomy but,more importantly,bacterial derived products that are likely to be potentially powerful stimuli for initiating the inflammatory response.Hence,the study of liver tissue microbiota offers the opportunity of changing the paradigm of host-NAFLD-microbial interactions from a“gut-centric”to a“liver-centric”approach.Here,we highlight the evidence on the role of liver tissue bacterial DNA in the biology of NAFLD and NASH.Besides,we provide evidence of metagenomic findings that can serve as the seed of further hypothesis-raising studies as well as can be leveraged to discover novel therapeutic targets.
基金Agencia Nacional de Promoción Científica y Tecnológica,Fondo para la Investigación Científica y Tecnológica(FonCyT)(PICT 2014-0432 and PICT 2015-0551 to SS and PICT 2014-1816 and 2016-0135 to CJ Pirola).
文摘Nonalcoholic fatty liver disease(NAFLD)is regarded as the most frequent cause of chronic liver damage(1,2).The natural history of the disease presents a complex scenario of potential progression into severe clinical outcomes,including nonalcoholic steatohepatitis(NASH),NASH-fibrosis,cirrhosis,and hepatocellular carcinoma(1,2).In addition,NAFLD is closely associated with comorbidities of the metabolic syndrome(MetS),including type 2 diabetes,obesity,arterial hypertension,and dyslipidemia,which together aggravate the morbidity and mortality associated with the disease.
基金Agencia Nacional de Promoción Científica yTecnológica, Fondo para la Investigación Científica y Tecnológica (FonCyT)(PICT 2014-0432 and PICT 2015-0551 to S Sookoian and PICT 2014-1816 and 2016-0135 to CJ Pirola).
文摘Nonalcoholic steatohepatitis (NASH)—the severe histological form of nonalcoholic fatty liver disease (NAFLD)—is regarded as a major health problem worldwide (1,2). The disease can progress to liver cirrhosis and eventually to hepatocellular carcinoma (1,3). Treatment of NASH and NASH-fibrosis is thus increasingly being given priority in the clinical field. Yet, these efforts face challenges not only related to the design and validation of novel pharmacological agents, but also to the need to optimize treatment options as well as improve access to therapies. In fact, while many drugs are currently being tested for safety and efifcacy, only a few approved options for the treatment of NASH presently exist (4,5). It is thus expected that, in the near future, emphasis will be given to selecting the right drug for treating NASH patients from a wide spectrum of treatment choices. Hence, identiifcation of early predictors of treatment response represents an unmet and relevant need.
