Cholestasis is a clinical condition resulting from the imapairment of bile flow.This condition could be caused by defects of the hepatocytes,which are responsible for the complex process of bile formation and secretio...Cholestasis is a clinical condition resulting from the imapairment of bile flow.This condition could be caused by defects of the hepatocytes,which are responsible for the complex process of bile formation and secretion,and/or caused by defects in the secretory machinery of cholangiocytes.Several mutations and pathways that lead to cholestasis have been described.Progressive familial intrahepatic cholestasis(PFIC)is a group of rare diseases caused by autosomal recessive mutations in the genes that encode proteins expressed mainly in the apical membrane of the hepatocytes.PFIC 1,also known as Byler’s disease,is caused by mutations of the ATP8B1 gene,which encodes the familial intrahepatic cholestasis 1 protein.PFIC 2 is characterized by the downregulation or absence of functional bile salt export pump(BSEP)expression via variations in the ABCB11 gene.Mutations of the ABCB4 gene result in lower expression of the multidrug resistance class 3 glycoprotein,leading to the third type of PFIC.Newer variations of this disease have been described.Loss of function of the tight junction protein 2 protein results in PFIC 4,while mutations of the NR1H4 gene,which encodes farnesoid X receptor,an important transcription factor for bile formation,cause PFIC 5.A recently described type of PFIC is associated with a mutation in the MYO5B gene,important for the trafficking of BSEP and hepatocyte membrane polarization.In this review,we provide a brief overview of the molecular mechanisms and clinical features associated with each type of PFIC based on peer reviewed journals published between 1993 and 2020.展开更多
Familial intrahepatic cholestasis(FIC) comprises a group of rare cholestatic liver diseases associated with canalicular transport defects resulting predominantly from mutations in ATP8B1, ABCB11 and ABCB4. Phe-notypes...Familial intrahepatic cholestasis(FIC) comprises a group of rare cholestatic liver diseases associated with canalicular transport defects resulting predominantly from mutations in ATP8B1, ABCB11 and ABCB4. Phe-notypes range from benign recurrent intrahepatic cholestasis(BRIC), associated with recurrent cholestatic attacks, to progressive FIC(PFIC). Patients often suffer from severe pruritus and eventually progressive cholestasis results in liver failure. Currently, first-line treatment includes ursodeoxycholic acid in patients with ABCB4 deficiency(PFIC3) and partial biliary diversion in patients with ATP8B1 or ABCB11 deficiency(PFIC1 and PFIC2). When treatment fails, liver transplantation is needed which is associated with complications like rejection, post-transplant hepatic steatosis and recurrence of disease. Therefore, the need for more and better therapies for this group of chronic diseases remains. Here, we discuss new symptomatic treatment options like total biliary diversion, pharmacological diversion of bile acids and hepatocyte transplantation. Furthermore, we focus on emerging mutation-targeted therapeutic strategies, providing an outlook for future personalized treatment for inherited cholestatic liver diseases.展开更多
AIM: To investigate mitochondrial ATP 6 and 8 poly-morphisms in the colon and ileum of patients with ir-ritable bowel syndrome with diarrhea (IBS-D). METHODS: Twenty-eight patients fulfilling the Rome Ⅲ criteria for ...AIM: To investigate mitochondrial ATP 6 and 8 poly-morphisms in the colon and ileum of patients with ir-ritable bowel syndrome with diarrhea (IBS-D). METHODS: Twenty-eight patients fulfilling the Rome Ⅲ criteria for IBS-D and 28 healthy subjects were in-vestigated. All study participants underwent screening colonoscopy and mucosal biopsies were obtained from the colon and/or terminal ileum. Genomic DNA was ex-tracted from specimens based on standard protocols. Mitochondrial ATP (MT-ATP) 6 and 8 genes in speci-mens were polymerase chain reaction amplified and sequenced. Sequencing data were analyzed via Variant Reporter Software and compared with the reference sequence from Genbank (accession No. NC_012920) to indicate possible polymorphisms. The protocol was registered at www.clinicaltrials.gov as NCT01028898. RESULTS: Twenty-five polymorphic sites of MT-ATP 6 and 8 genes were detected and 12 of them were missense mutations. A median of two polymorphic sites in MT-ATP genes was found in colon specimens of controls while a median of three polymorphic sites was noted in patients with IBS-D (Mann-Whitney test, P=0.012). The variants of the colon and ileum speci-mens from the same subjects were identical in all but one case. Symptom duration in IBS was not found to be a significant factor associated with the mtDNA polymorphism (Spearman correlation, P=0.592). The mitochondrial DNA change at 8860 was present in all cases of both groups. The frequency of the 8701 poly-morphism was found to be the second most frequent; however, no statistical difference was noted between the groups (χ2 test, P=0.584). CONCLUSION: Patients with IBS-D have a higher inci-dence of MT-ATP 6 and 8 polymorphisms than healthy subjects, implying that the mtDNA polymorphism may play a role in IBS-D.展开更多
BACKGROUND Benign recurrent intrahepatic cholestasis is a genetic disorder with recurrent cholestatic jaundice due to ATP8B1 and ABCB11 gene mutations encoding for hepato-canalicular transporters.Herein,we firstly pro...BACKGROUND Benign recurrent intrahepatic cholestasis is a genetic disorder with recurrent cholestatic jaundice due to ATP8B1 and ABCB11 gene mutations encoding for hepato-canalicular transporters.Herein,we firstly provide the evidence that a nonsense variant of ATP8B1 gene(c.1558A>T)in heterozygous form is involved in BRIC pathogenesis.CASE SUMMARY A 29-year-old male showed severe jaundice and laboratory tests consistent with intrahepatic cholestasis despite normal gamma-glutamyltranspeptidase.Acute and chronic liver diseases with viral,metabolic and autoimmune etiology were excluded.Normal intra/extra-hepatic bile ducts were demonstrated by magnetic resonance.Liver biopsy showed:Cholestasis in the centrilobular and intermediate zones with bile plugs and intra-hepatocyte pigment,Kupffer’s cell activation/hyperplasia and preserved biliary ducts.Being satisfied benign recurrent intrahepatic cholestasis diagnostic criteria,ATP8B1 and ABCB11 gene analysis was performed.Surprisingly,we found a novel nonsense variant of ATP8B1 gene(c.1558A>T)in heterozygosis.The variant was confirmed by Sanger sequencing following a standard protocol and tested for familial segregation,showing a maternal inheritance.Immunohistochemistry confirmed a significant reduction of mutated gene related protein(familial intrahepatic cholestasis 1).The patient was treated with ursodeoxycholic acid 15 mg/kg per day and colestyramine 8 g daily with total bilirubin decrease and normalization at the 6th and 12th mo.CONCLUSION A genetic abnormality,different from those already known,could be involved in familial intrahepatic cholestatic disorders and/or pro-cholestatic genetic predisposition,thus encouraging further mutation detection in this field.展开更多
BACKGROUND Benign recurrent intrahepatic cholestasis(BRIC)is a rare autosomal recessive disorder,characterized by episodes of intense pruritus,elevated serum levels of alkaline phosphatase and bilirubin,and near-norma...BACKGROUND Benign recurrent intrahepatic cholestasis(BRIC)is a rare autosomal recessive disorder,characterized by episodes of intense pruritus,elevated serum levels of alkaline phosphatase and bilirubin,and near-normal-glutamyl transferase.These episodes may persist for weeks to months before spontaneously resolving,with patients typically remaining asymptomatic between occurrences.Diagnosis entails the evaluation of clinical symptoms and targeted genetic testing.Although BRIC is recognized as a benign genetic disorder,the triggers,particularly psychosocial factors,remain poorly understood.CASE SUMMARY An 18-year-old Chinese man presented with recurrent jaundice and pruritus after a cold,which was exacerbated by self-medication involving vitamin B and paracetamol.Clinical and laboratory evaluations revealed elevated levels of bilirubin and liver enzymes,in the absence of viral or autoimmune liver disease.Imaging excluded biliary and pancreatic abnormalities,and liver biopsy demonstrated centrilobular cholestasis,culminating in a BRIC diagnosis confirmed by the identification of a novel ATP8B1 gene mutation.Psychological assessment of the patient unveiled stress attributable to academic and familial pressures,regarded as potential triggers for BRIC.Initial relief was observed with ursodeoxycholic acid and cetirizine,followed by an adjustment of the treatment regimen in response to elevated liver enzymes.The patient's condition significantly improved following a stress-related episode,thanks to a comprehensive management approach that included psychosocial support and medical treatment.CONCLUSION Our research highlights genetic and psychosocial influences on BRIC,emphasizing integrated diagnostic and management strategies.展开更多
Benign recurrent intrahepatic cholestasis （BRIC） is a Prare autosomal recessive liver disease characterizedby intermittent attacks of cholestasis that was first reported by Summerskill and Walshe in 1959.1 A few rep...Benign recurrent intrahepatic cholestasis （BRIC） is a Prare autosomal recessive liver disease characterizedby intermittent attacks of cholestasis that was first reported by Summerskill and Walshe in 1959.1 A few reports on patients with BRIC in China have been described in recent years, however, it is still a challenge to give the patients a correct diagnosis. Therefore, we collected five cases in the Beijing Friendship Hospital and the China-Japan Friendship Hospital in the past two years to summarize their clinical features, and explore the mutation region of the ATP8B1 gene from Chinese patients with BRIC.展开更多
对西藏16个牦牛类群共367头个体的mt DNA ATP8（Adenosine Triphosphate 8）基因进行克隆及序列分析。结果表明,西藏牦牛mt DNA ATP8基因全长201-203 bp,T、C、A和G 4种核苷酸的平均比例分别为29.3%、23.0%、41.8%和6.0%,A＋T含量明显高...对西藏16个牦牛类群共367头个体的mt DNA ATP8（Adenosine Triphosphate 8）基因进行克隆及序列分析。结果表明,西藏牦牛mt DNA ATP8基因全长201-203 bp,T、C、A和G 4种核苷酸的平均比例分别为29.3%、23.0%、41.8%和6.0%,A＋T含量明显高于G＋C,表现出一定的碱基偏倚性;在367头牦牛中,共检测到19个变异位点,其中单一信息位点15个,简约信息位点4个,存在转换和插入2种变异类型,碱基替换中存在转换73次,以A/G、T/C为主,占98.63%;在插入变异类型中以A碱基插入为主;367头牦牛共捡出20种单倍型,单倍型多样性和核苷酸多样性指数分别为0.332和0.001 89,说明西藏牦牛具有较贫乏的遗传多样性;聚类分析显示,西藏牦牛可分为2类,其中桑日牦牛、类乌齐牦牛和桑日牦牛为1类,其余牦牛类群为另1类。20种单倍型可以分为2个聚类簇（I和Ⅱ）,其中聚类簇I包含17种单倍型,占全部单倍型数的77.27%,包含了本次研究中的所有西藏牦牛类群;聚类簇Ⅱ中有3种单倍型,囊括了除错那、嘉黎、康布和帕里类群外的12个类群,显示西藏牦牛存在2个母系起源。展开更多
基金Supported by NIH,No.UG3TR003289 to Soto-Gutierrez A.
文摘Cholestasis is a clinical condition resulting from the imapairment of bile flow.This condition could be caused by defects of the hepatocytes,which are responsible for the complex process of bile formation and secretion,and/or caused by defects in the secretory machinery of cholangiocytes.Several mutations and pathways that lead to cholestasis have been described.Progressive familial intrahepatic cholestasis(PFIC)is a group of rare diseases caused by autosomal recessive mutations in the genes that encode proteins expressed mainly in the apical membrane of the hepatocytes.PFIC 1,also known as Byler’s disease,is caused by mutations of the ATP8B1 gene,which encodes the familial intrahepatic cholestasis 1 protein.PFIC 2 is characterized by the downregulation or absence of functional bile salt export pump(BSEP)expression via variations in the ABCB11 gene.Mutations of the ABCB4 gene result in lower expression of the multidrug resistance class 3 glycoprotein,leading to the third type of PFIC.Newer variations of this disease have been described.Loss of function of the tight junction protein 2 protein results in PFIC 4,while mutations of the NR1H4 gene,which encodes farnesoid X receptor,an important transcription factor for bile formation,cause PFIC 5.A recently described type of PFIC is associated with a mutation in the MYO5B gene,important for the trafficking of BSEP and hepatocyte membrane polarization.In this review,we provide a brief overview of the molecular mechanisms and clinical features associated with each type of PFIC based on peer reviewed journals published between 1993 and 2020.
文摘Familial intrahepatic cholestasis(FIC) comprises a group of rare cholestatic liver diseases associated with canalicular transport defects resulting predominantly from mutations in ATP8B1, ABCB11 and ABCB4. Phe-notypes range from benign recurrent intrahepatic cholestasis(BRIC), associated with recurrent cholestatic attacks, to progressive FIC(PFIC). Patients often suffer from severe pruritus and eventually progressive cholestasis results in liver failure. Currently, first-line treatment includes ursodeoxycholic acid in patients with ABCB4 deficiency(PFIC3) and partial biliary diversion in patients with ATP8B1 or ABCB11 deficiency(PFIC1 and PFIC2). When treatment fails, liver transplantation is needed which is associated with complications like rejection, post-transplant hepatic steatosis and recurrence of disease. Therefore, the need for more and better therapies for this group of chronic diseases remains. Here, we discuss new symptomatic treatment options like total biliary diversion, pharmacological diversion of bile acids and hepatocyte transplantation. Furthermore, we focus on emerging mutation-targeted therapeutic strategies, providing an outlook for future personalized treatment for inherited cholestatic liver diseases.
文摘AIM: To investigate mitochondrial ATP 6 and 8 poly-morphisms in the colon and ileum of patients with ir-ritable bowel syndrome with diarrhea (IBS-D). METHODS: Twenty-eight patients fulfilling the Rome Ⅲ criteria for IBS-D and 28 healthy subjects were in-vestigated. All study participants underwent screening colonoscopy and mucosal biopsies were obtained from the colon and/or terminal ileum. Genomic DNA was ex-tracted from specimens based on standard protocols. Mitochondrial ATP (MT-ATP) 6 and 8 genes in speci-mens were polymerase chain reaction amplified and sequenced. Sequencing data were analyzed via Variant Reporter Software and compared with the reference sequence from Genbank (accession No. NC_012920) to indicate possible polymorphisms. The protocol was registered at www.clinicaltrials.gov as NCT01028898. RESULTS: Twenty-five polymorphic sites of MT-ATP 6 and 8 genes were detected and 12 of them were missense mutations. A median of two polymorphic sites in MT-ATP genes was found in colon specimens of controls while a median of three polymorphic sites was noted in patients with IBS-D (Mann-Whitney test, P=0.012). The variants of the colon and ileum speci-mens from the same subjects were identical in all but one case. Symptom duration in IBS was not found to be a significant factor associated with the mtDNA polymorphism (Spearman correlation, P=0.592). The mitochondrial DNA change at 8860 was present in all cases of both groups. The frequency of the 8701 poly-morphism was found to be the second most frequent; however, no statistical difference was noted between the groups (χ2 test, P=0.584). CONCLUSION: Patients with IBS-D have a higher inci-dence of MT-ATP 6 and 8 polymorphisms than healthy subjects, implying that the mtDNA polymorphism may play a role in IBS-D.
文摘BACKGROUND Benign recurrent intrahepatic cholestasis is a genetic disorder with recurrent cholestatic jaundice due to ATP8B1 and ABCB11 gene mutations encoding for hepato-canalicular transporters.Herein,we firstly provide the evidence that a nonsense variant of ATP8B1 gene(c.1558A>T)in heterozygous form is involved in BRIC pathogenesis.CASE SUMMARY A 29-year-old male showed severe jaundice and laboratory tests consistent with intrahepatic cholestasis despite normal gamma-glutamyltranspeptidase.Acute and chronic liver diseases with viral,metabolic and autoimmune etiology were excluded.Normal intra/extra-hepatic bile ducts were demonstrated by magnetic resonance.Liver biopsy showed:Cholestasis in the centrilobular and intermediate zones with bile plugs and intra-hepatocyte pigment,Kupffer’s cell activation/hyperplasia and preserved biliary ducts.Being satisfied benign recurrent intrahepatic cholestasis diagnostic criteria,ATP8B1 and ABCB11 gene analysis was performed.Surprisingly,we found a novel nonsense variant of ATP8B1 gene(c.1558A>T)in heterozygosis.The variant was confirmed by Sanger sequencing following a standard protocol and tested for familial segregation,showing a maternal inheritance.Immunohistochemistry confirmed a significant reduction of mutated gene related protein(familial intrahepatic cholestasis 1).The patient was treated with ursodeoxycholic acid 15 mg/kg per day and colestyramine 8 g daily with total bilirubin decrease and normalization at the 6th and 12th mo.CONCLUSION A genetic abnormality,different from those already known,could be involved in familial intrahepatic cholestatic disorders and/or pro-cholestatic genetic predisposition,thus encouraging further mutation detection in this field.
文摘BACKGROUND Benign recurrent intrahepatic cholestasis(BRIC)is a rare autosomal recessive disorder,characterized by episodes of intense pruritus,elevated serum levels of alkaline phosphatase and bilirubin,and near-normal-glutamyl transferase.These episodes may persist for weeks to months before spontaneously resolving,with patients typically remaining asymptomatic between occurrences.Diagnosis entails the evaluation of clinical symptoms and targeted genetic testing.Although BRIC is recognized as a benign genetic disorder,the triggers,particularly psychosocial factors,remain poorly understood.CASE SUMMARY An 18-year-old Chinese man presented with recurrent jaundice and pruritus after a cold,which was exacerbated by self-medication involving vitamin B and paracetamol.Clinical and laboratory evaluations revealed elevated levels of bilirubin and liver enzymes,in the absence of viral or autoimmune liver disease.Imaging excluded biliary and pancreatic abnormalities,and liver biopsy demonstrated centrilobular cholestasis,culminating in a BRIC diagnosis confirmed by the identification of a novel ATP8B1 gene mutation.Psychological assessment of the patient unveiled stress attributable to academic and familial pressures,regarded as potential triggers for BRIC.Initial relief was observed with ursodeoxycholic acid and cetirizine,followed by an adjustment of the treatment regimen in response to elevated liver enzymes.The patient's condition significantly improved following a stress-related episode,thanks to a comprehensive management approach that included psychosocial support and medical treatment.CONCLUSION Our research highlights genetic and psychosocial influences on BRIC,emphasizing integrated diagnostic and management strategies.
文摘Benign recurrent intrahepatic cholestasis （BRIC） is a Prare autosomal recessive liver disease characterizedby intermittent attacks of cholestasis that was first reported by Summerskill and Walshe in 1959.1 A few reports on patients with BRIC in China have been described in recent years, however, it is still a challenge to give the patients a correct diagnosis. Therefore, we collected five cases in the Beijing Friendship Hospital and the China-Japan Friendship Hospital in the past two years to summarize their clinical features, and explore the mutation region of the ATP8B1 gene from Chinese patients with BRIC.
文摘对西藏16个牦牛类群共367头个体的mt DNA ATP8（Adenosine Triphosphate 8）基因进行克隆及序列分析。结果表明,西藏牦牛mt DNA ATP8基因全长201-203 bp,T、C、A和G 4种核苷酸的平均比例分别为29.3%、23.0%、41.8%和6.0%,A＋T含量明显高于G＋C,表现出一定的碱基偏倚性;在367头牦牛中,共检测到19个变异位点,其中单一信息位点15个,简约信息位点4个,存在转换和插入2种变异类型,碱基替换中存在转换73次,以A/G、T/C为主,占98.63%;在插入变异类型中以A碱基插入为主;367头牦牛共捡出20种单倍型,单倍型多样性和核苷酸多样性指数分别为0.332和0.001 89,说明西藏牦牛具有较贫乏的遗传多样性;聚类分析显示,西藏牦牛可分为2类,其中桑日牦牛、类乌齐牦牛和桑日牦牛为1类,其余牦牛类群为另1类。20种单倍型可以分为2个聚类簇（I和Ⅱ）,其中聚类簇I包含17种单倍型,占全部单倍型数的77.27%,包含了本次研究中的所有西藏牦牛类群;聚类簇Ⅱ中有3种单倍型,囊括了除错那、嘉黎、康布和帕里类群外的12个类群,显示西藏牦牛存在2个母系起源。
