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ABSTRACT: Wilson disease (WD) is an autosomal recessive disorder resulting from mutations in the ATP7B gene, with over 600 mutations described. Identification of mutations has made genetic diagnosis of WD feasible in many countries. The heterogeneity of ATP7B mutants is, however, yet to be identified in the Indian population. We analyzed the mutational pattern of WD in a large region of Western India. We studied patients (n = 52) for ATP7B gene mutations in a cohort of families with WD and also in first-degree relatives (n = 126). All 21 exon-intron boundaries of the WD gene were amplified and directly sequenced. We identified 36 different disease-causing mutations (31 exonic and five intronic splice site variants). Fourteen novel mutations were identified. Exons 2, 8, 13, 14, and 18 accounted for the majority of mutations (86.4%). A previously recognized mutation, p.C271*, and the novel mutation p.E122fs, were the most common mutations with allelic frequencies of 20.2% and 10.6%, respectively. Frequent homozygous mutations (58.9%) and disease severity assessments allowed analysis of genotype-phenotype correlations. Our study significantly adds to the emerging data from other parts of India suggesting that p.C271* may be the most frequent mutation across India, and may harbor a moderate to severely disabling phenotype with limited variability.
Annals of Human Genetics 04/2013; · 2.57 Impact Factor
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ABSTRACT: PURPOSE: MicroRNA-122 (miR-122) has recently been shown to represent a novel biomarker of liver disease. However, the presence of serum miR-122 after liver injury was mostly studied at singular time points. The course of serum miR-122 was determined at consecutive time points during the onset of disease. METHODS: Fulminant hepatitis was induced by a high-copper diet in Long-Evans Cinnamon (LEC) rats that were used as models for Wilson's disease (WD). Levels of serum miR-122, alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, and liver histology were determined. RESULTS: Toxic copper given to isolated hepatocytes induced release of miR-122 into the tissue culture medium. Levels of serum miR-122 were highly elevated (21.9 ± 5) in LEC rats after high-copper diet in fulminant hepatitis, whereas healthy rats showed low (<0.6) baseline levels of miR-122. Levels of miR-122 in the serum of LEC rats after high-copper diet continuously increased for about 4 weeks prior to the onset of fulminant hepatitis. In most of the animals (77.8%), significantly increased levels of miR-122 were detected about 2 weeks (13.7 ± 2 days) earlier as compared to hepatitis-associated serum markers ALT, AST, and bilirubin. Analysis of miR-122 in survivors after cell-based therapy of WD demonstrated a rapid decrease of miR-122 levels following hepatocyte transplantation. miR-122 expression in the serum was normalized to baseline levels in most of the (4/5) survivors. CONCLUSION: Our results suggest that longitudinal analysis of miR-122 allows detection of severe liver disease at an early stage and might be excellently suited to monitor therapy, at least when severe liver disease can be restored as observed after cell-based therapy of WD. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12072-012-9348-5) contains supplementary material, which is available to authorized users.
Hepatology International 10/2012; 6(4):770-777. · 2.64 Impact Factor
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ABSTRACT: The outcome of consecutive hepatocyte transplants was explored in a rat model of Wilson's disease before the onset of fulminant hepatitis without preconditioning regimens. Rats received a high-copper diet in order to induce a rapid induction of liver failure. Sham-operated rats (15/15) developed jaundice and fulminant hepatitis, and they died within 4 weeks of first transplantation. Despite the continuation of a high dietary copper challenge, long-term survival was observed for a notable proportion of the transplanted animals (7/18). All survivors displayed normalized levels of hepatitis-associated serum markers and ceruloplasmin oxidase activity by posttransplant days 50 and 98, respectively. The liver copper concentrations, the liver histology, and the expression of marker genes were significantly restored within 4 months of transplantation in comparison with the control group. The high expression of a copper transporter gene (ATPase Cu++ transporting beta polypeptide) in the livers of the survivors indicated a high rate of repopulation by donor hepatocytes. Our data suggest that repeated cell transplantation can overcome the limitations of a single therapy session in rats with severe hepatic disease by functionally restoring the host liver without preconditioning.
Liver Transplantation 12/2011; 18(2):248-59. · 3.39 Impact Factor
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ABSTRACT: The increasing demand for transplantation has led to consideration of liver grafts from donors exposed to hepatitis B virus (HBV). Six transplantations of liver grafts from hepatitis B surface antigen (HBsAg) positive donors have been reported; two recipients suffered from HBV/HDV (hepatitis Delta virus) coinfection and were followed up for 10-12 months. Here, we report a 56 months follow-up of a HBV/HDV-coinfected recipient of a HBsAg positive liver graft. Posttransplant combination prophylaxis consisted of hepatitis immunoglobulin, lamivudine and adefovir dipivoxil. HBsAg remained positive during stable posttransplant follow-up and subclinical HDV reinfection with low replication rate was detected at 1 month. Pegylated interferon therapy was introduced after documentation of histological evidence of mild chronic hepatitis, but without virological response after 48 weeks. Finally, antiviral treatment was switched to tenofovir disoproxil fumarate. More than 50 months posttransplant the recipient revealed clinical symptoms of decompensated liver cirrhosis and has been relisted for liver transplantation. In conclusion HBsAg positive liver grafts in HBsAg positive recipients with HDV coinfection may result in virological recurrence and rapid development of liver cirrhosis.
Annals of hepatology: official journal of the Mexican Association of Hepatology 06/2011; 10(3):355-60. · 1.81 Impact Factor
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ABSTRACT: The regeneration capacity of cirrhotic livers might be affected by angiotensin-1 (AT1) receptors located on hepatic stellate cells (HSC). The effect of AT1 receptor blockade on microcirculation, fibrosis and liver regeneration was investigated.
In 112 Lewis rats, cirrhosis was induced by repetitive intraperitoneal injections of CCl(4) . Six hours, 3, 7 and 14 days after partial hepatectomy or sham operation, rats were sacrificed for analysis. Animals were treated with either vehicle or 5 mg/kg body weight losartan pre-operatively and once daily after surgery by gavage. Microcirculation and portal vein flow were investigated at 6 h. The degree of cirrhosis was assessed by Azan Heidenhein staining, activation of HSC by desmin staining, apoptosis by ssDNA detection and liver regeneration by Ki-67 staining. Changes in expression of various genes important for liver regeneration and fibrosis were analysed at 6 h and 3 days. Haemodynamic parameters and liver enzymes were monitored.
Losartan treatment increased sinusoidal diameter, sinusoidal blood flow and portal vein flow after partial hepatectomy (P<0.05), but not after sham operation. AT1 receptor blockade resulted in increased apoptosis early after resection. HSC activation was reduced and after 7 days, a significantly lower degree of cirrhosis in resected animals was observed. Losartan increased the proliferation of hepatocytes at late time-points and of non-parenchymal cells early after partial hepatectomy (P<0.05). Tumour necrosis factor (TNF)-α was significantly upregulated at 6 h and stem cell growth factor (SCF) was downregulated at 3 days (P<0.05).
Losartan increased hepatic blood flow, reduced HSC activation and liver fibrosis, but interfered with hepatocyte proliferation after partial hepatectomy in cirrhotic livers.
Liver international: official journal of the International Association for the Study of the Liver 05/2011; 31(5):642-55. · 3.82 Impact Factor
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Michael Boschmann,
Stefan Engeli,
Cedric Moro,
Angelika Luedtke,
Frauke Adams,
Kerstin Gorzelniak,
Gabriele Rahn,
Anja Mähler,
Kerstin Dobberstein,
Antje Krüger,
Saskia Schmidt,
Simone Spuler,
Friedrich C Luft,
Steven R Smith, Hartmut H-J Schmidt,
Jens Jordan
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ABSTRACT: Type 2 familial partial lipodystrophy (FPLD) is an autosomal-dominant lamin A/C-related disease associated with exercise intolerance, muscular pain, and insulin resistance. The symptoms may all be explained by defective metabolism; however, metabolism at the tissue level has not been investigated.
We hypothesized that in FPLD, insulin resistance and impaired aerobic exercise capacity are explained by a common underlying mechanism, presumably a muscular metabolic defect.
Carbohydrate and lipid metabolism was studied on 10 FPLD patients, one patient with limb-girdle muscular dystrophy (LGMD1B, a different lamin A/C disease), and 10 healthy control subjects before and during an oral glucose tolerance test by indirect calorimetry and im microdialysis. Muscle biopsies were taken for in vitro studies.
We observed marked increased skeletal muscle fatty acid beta-oxidation rate in vitro and in vivo, even after glucose ingestion in FPLD patients. However, fatty acid oxidation was largely incomplete and accompanied by increased ketogenesis. The lipid oxidation abnormality was associated with impaired glucose disposition through reduction in glucose oxidation, rather than decreased cellular glucose uptake. A microarray showed down-regulation of complex I respiratory chain, glycolysis, and nuclear transport genes. Although not overtly insulin resistant, the LGMD1B patient showed similar metabolic derangements as the FPLD patients.
Our study suggests imbalance between lipid oxidation and oxidative glucose metabolism in FPLD and LGMD1B patients. The observation suggests an intrinsic defect in skeletal muscle metabolism due to lamin A/C dysfunction. The metabolic FPLD phenotype likely results from this intrinsic defect combined with lipodystrophic "lipid pressure" due to decreased adipose tissue lipid storage capacity.
The Journal of clinical endocrinology and metabolism 04/2010; 95(4):1634-43. · 6.50 Impact Factor
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ABSTRACT: Wilson's disease (WD) is characterized by accumulation of high levels of copper in liver due to malfunction of copper transporter ATP7B which is central for copper homeostasis. Here we report for the first time that mesenchymal stem cells (MSC) derived from bone marrow express detectable levels of ATP7B. The role of ATP7B overexpression for MSC survival and selection in high copper was investigated. Hepatoma cell line HepG2 that has a high intrinsic expression of ATP7B served as a control. Using retroviral vector a significant higher expression level of ATP7B could be achieved in MSCs. Whereas copper treatment resulted in cell death in untransduced MSCs, viability assays demonstrated a unique copper resistance of ATP7B overexpressing MSCs that outcompeted HepG2. In long-term cell culture stable transgene expression for up to 9weeks was shown for ATP7B overexpressing MSCs which rapidly overgrew untransduced cells. Our findings suggest that ATP7B overexpression provides an important selection advantage to MSCs in high copper microenvironments, and may represent novel cell transplants for therapy of WD.
Biochemical and Biophysical Research Communications 03/2010; 395(3):307-11. · 2.48 Impact Factor
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European Journal of Internal Medicine 02/2009; 20(1):e3-4. · 2.00 Impact Factor
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Hartmut H-J Schmidt
Journal of Hepatology 01/2009; 50(3):449-52. · 9.26 Impact Factor
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Carsten Büning, Hartmut H-J Schmidt,
Tamás Molnár,
Joost Ph Drenth,
Thomas Fiedler,
Enno Gentz,
Theodor Todorov,
Daniel C Baumgart,
Andreas Sturm,
Ferenc Nagy,
János Lonovics,
Dirk J de Jong,
Olfert Landt,
Andreas Kage,
Renate Nickel,
Janine Büttner,
Herbert Lochs,
Heiko Witt
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ABSTRACT: A recent study reported that the c.30T>A (p.Cys10Ter; rs2043211) variant, in the CARD8 (TUCAN) gene, is associated with Crohn's disease (CD). The aim of this study was to analyze the frequency of p.C10X in 3 independent European (IBD) cohorts from Germany, Hungary, and the Netherlands.
We included a European IBD cohort of 921 patients and compared the p.C10X genotype frequency to 832 healthy controls. The 3 study populations analyzed were: (1) Germany [CD, n = 317; ulcerative colitis (UC), n = 180], (2) Hungary (CD, n = 149; UC, n = 119), and (3) the Netherlands (CD, n = 156). Subtyping analysis was performed in respect to NOD2 variants (p.Arg702Trp, p.Gly908Arg, c.3020insC) and to clinical characteristics. Ethnically matched controls were included (German, n = 413; Hungarian, n = 202; Dutch, n = 217).
We observed no significant difference in p.C10X genotype frequency in either patients with CD or patients with UC compared with controls in all 3 cohorts. Conversely to the initial association study, we found a trend toward lower frequencies of the suggestive risk wild type in CD from the Netherlands compared with controls (P = 0.14). We found neither evidence for genetic interactions between p.C10X and NOD2 nor the C10X variant to be associated with a CD or UC phenotype.
Analyzing 3 independent European IBD cohorts, we found no evidence that the C10X variant in CARD8 confers susceptibility for CD.
Inflammatory Bowel Diseases 03/2008; 14(3):332-7. · 4.86 Impact Factor
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Carsten Büning,
Tahir Durmus,
Tamas Molnar,
Dirk J de Jong,
Joost P H Drenth,
Thomas Fiedler,
Enno Gentz,
Theodor Todorov,
Verena Haas,
Sabine Buhner, [......],
Ferenc Nagy,
Janos Lonovics,
Olfert Landt,
Andreas Kage,
Herbert Büning,
Renate Nickel,
Janine Büttner,
Herbert Lochs, Hartmut H-J Schmidt,
Heiko Witt
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ABSTRACT: A recent study reported that a nonsynonymous SNP rs2241880 (c.898A>G, p.Thr300Ala) within ATG16L1 confers susceptibility to Crohn's disease (CD). We analyzed ATG16L1 c.898A>G in three independent European inflammatory bowel disease (IBD) cohorts from Germany, Hungary and the Netherlands.
In total, we included 910 European IBD patients and compared the ATG16L1 c.898A>G genotype frequency with 707 ethnically matched healthy controls. We included patients from 3 populations originating from Germany (CD n=310; ulcerative colitis [UC] n=179), Hungary (CD n=147; UC n=117), and the Netherlands (CD n=157). Subtyping analysis was performed in respect to CARD15 alterations and clinical characteristics.
We found a highly significant association of c.898A>G to CD. The association was significant (p=0.0005) for the total CD cohort but also for the individual populations from Germany (p=0.02) and Netherlands (p=0.02) whereas in the Hungarian CD patients a clear trend was observed (p=0.19; OR 1.227, 95% CI 0.910; 1.654). No association was found between c.898A>G and UC. No statistical interactions were observed between ATG16L1 c.898A>G and CARD15 variants. Furthermore no association to a CD subphenotype was detected.
We confirm that ATG16L1 variant c898A>G confers a risk variant for CD but is not associated with a distinct CD phenotype.
Journal of Crohn s and Colitis 12/2007; 1(2):70-6. · 2.57 Impact Factor
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ABSTRACT: Familial partial lipodystrophy caused by mutations in the PPARG gene is characterised by altered distribution of subcutaneous fat, muscular hypertrophy and symptoms of metabolic syndrome. PPARG encodes peroxisome proliferator-activated receptor (PPAR)gamma, a nuclear hormone receptor playing a crucial role in lipid and glucose metabolism and in several other cellular regulatory processes.
PPARG was screened for mutations by direct sequencing in two patients with lipodystrophy, one unaffected family member and 124 controls. Body composition was examined in affected patients, and they were investigated for abnormalities in laboratory results. Functional analysis of the mutant protein was assessed by determining transcriptional activity and possible interference with the wild-type protein.
In two patients with familial partial lipodystrophy, we identified a nucleotide substitution in the PPARG gene. This mutation results in the substitution of aspartate by asparagine at residue 424 (D424N) in the ligand-binding domain of PPARgamma. The unaffected family member and all 124 controls did not carry this mutation. D424N PPARgamma had a significantly lower ability than wild-type PPARgamma to activate a PPARgamma-stimulated reporter gene, but did not exert a negative effect on the wild-type protein. Partial activation of D424N PPARgamma was achieved in the presence of the agonist rosiglitazone.
We report a new PPARG mutation, D424N, which is located in the ligand-binding domain of the protein and leads to familial partial lipodystrophy. D424N PPARgamma exhibited a loss of function, which was partially restored by adding the PPARgamma agonist rosiglitazone, suggesting possible treatment potential of this agent.
Journal of Medical Genetics 10/2007; 44(9):e88. · 6.36 Impact Factor
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ABSTRACT: Mutations in PPARG are associated with insulin resistance and familial partial lipodystrophy, a disease characterized by altered distribution of sc fat and symptoms of the metabolic syndrome. The encoded protein, peroxisome proliferator-activated receptor (PPAR)-gamma, plays a pivotal role in regulating lipid and glucose metabolism, the differentiation of adipocytes, and other cellular regulatory processes.
The objective of the study was to detect a novel PPARG mutation in a kindred with partial lipodystrophy and analyze the functional characteristics of the mutant protein.
In three subjects with partial lipodystrophy, one unaffected family member, and 124 unaffected subjects, PPARG was screened for mutations by direct sequencing. Body composition, laboratory abnormalities, and hepatic steatosis were assessed in each affected subject. Transcriptional activity was determined, and EMSA was performed to investigate DNA binding capacity of the mutant protein.
We identified a PPARG mutation, C190S, causing partial lipodystrophy with metabolic alterations in three affected family members. The mutation was absent in the unaffected family member and unaffected controls. The mutation is located within zinc-finger 2 of the DNA binding domain. C190S PPARgamma has a significantly lower ability to activate a reporter gene than wild-type PPARgamma in absence and presence of rosiglitazone. A dominant-negative effect was not observed. Compared with wild-type PPARgamma, C190S PPARgamma shows a reduced capacity to bind DNA.
Mutation of a zinc-binding amino acid of PPARgamma leads to an altered protein-DNA binding pattern, resulting in a partial loss of function, which in turn is associated with partial lipodystrophy.
Journal of Clinical Endocrinology & Metabolism 07/2007; 92(6):2248-55. · 6.50 Impact Factor
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Medizinische Klinik 11/2006; 101(10):825-9. · 0.34 Impact Factor
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09/2006; 101(10):825-829.
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Andreas Perrot,
Holger H Sigusch,
Herbert Nägele,
Janine Genschel,
Hans Lehmkuhl,
Roland Hetzer,
Christian Geier,
Veronica Leon Perez,
Dirk Reinhard,
Rainer Dietz,
Karl Josef Osterziel, Hartmut H-J Schmidt
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ABSTRACT: One-third of cases of dilated cardiomyopathy (DCM) is of familial aetiology. Several genes have been reported to cause the autosomal dominant form of DCM.
To analyze the lamin A/C gene (LMNA) in 31 unrelated patients with DCM and conduction system disease (CSD).
Patients and family members underwent physical examination, ECG/Holter-ECG, echocardiography, and selective coronary angiography. Genetic analysis of all coding exons of LMNA was performed using PCR and sequencing.
Three different LMNA mutations (Arg377His, c.1397delA, c.424_425ins21nt) were identified in three families with autosomal dominant disease comprised of 39 individuals. 21 individuals were mutation carriers, of whom 12 were symptomatic. We observed a progressive and age-dependent form of DCM with CSD and arrhythmias. First, the patients developed a moderate left ventricular dilatation without symptoms. Later, systolic function declined progressively and the patients became symptomatic resulting in a high mortality due to sudden death and heart failure.
Genetic screening leads to the identification of symptomatic and asymptomatic mutant carriers. The latter at a young age should be regarded as "presymptomatic" because of the age-dependent disease manifestation. New guidelines are required for the management of these individuals.
European Journal of Heart Failure 09/2006; 8(5):484-93. · 4.90 Impact Factor
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Carsten Büning,
Lars Geerdts,
Thomas Fiedler,
Enno Gentz,
Ghyslaine Pitre,
Wolf Reuter,
Werner Luck,
Sabine Buhner,
Tomas Molnar,
Ferenc Nagy,
Janos Lonovics,
Axel Dignass,
Olfert Landt,
Renate Nickel,
Janine Genschel,
Herbert Lochs, Hartmut H-J Schmidt,
Heiko Witt
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ABSTRACT: Genetic variants within DLG5 were recently reported to be associated with inflammatory bowel disease (IBD). The aim of our study was to test for allelic and haplotype associations of six DLG5 variants in 668 IBD patients from two European populations. Furthermore, we evaluated whether DLG5 variants alter gastrointestinal permeability in Crohn's disease (CD).
Six DLG5 variants (p.R30Q, p.P1371Q, p.G1066G, rs2289308, DLG_e26, p.D1507D) were genotyped in two study populations: (1) German IBD patients (CD n = 250; ulcerative colitis (UC) n = 150) and German healthy controls (n = 422); (2) Hungarian IBD patients (CD n = 144; UC n = 124) and Hungarian healthy controls (n = 205). Subtyping analysis was performed in respect of CARD15 mutations and clinical characteristics. We also tested for differences within DLG5 genotypes in German CD patients with respect to gastroduodenal and intestinal permeability measured by triple-sugar-test.
Allele as well as genotype frequencies of DLG5 variants did not differ between IBD patients and controls in either study population. Indeed, the p.R30Q polymorphism was found more frequently in controls than in patients. The distribution of DLG5 genotypes in German and Hungarian CD patients with CARD15 mutations was not different from patients without mutated CARD15. We did also not observe any association between DLG5 variants and clinical parameters. Importantly, DLG5 variants were not associated with gastroduodenal or intestinal permeability.
We could not replicate that DLG5 is a relevant disease susceptibility gene for IBD in German or Hungarian subjects. In addition, we have no evidence that DLG5 variants are involved in altered gastrointestinal permeability in CD.
The American Journal of Gastroenterology 05/2006; 101(4):786-92. · 7.28 Impact Factor
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ABSTRACT: Therapeutic options for hepatitis C non-responder patients are limited.
We initiated an open-label pilot study to investigate the efficacy of CIFN plus ribavirin on viral kinetics, sustained virological response (SVR), and histological response in hepatitis C non-responder patients. Seventy-seven patients were enrolled to receive CIFN given daily in combination with 1000/1200 mg ribavirin. An 8-week induction-dosing regimen of 18 microg CIFN, followed by 9 microg for 40 weeks was compared to 9 microg CIFN for 48 weeks. 90% of patients were infected with HCV-genotype 1.
Overall, 82% of the patients demonstrated an early virological response, 65% had an end-of-treatment response, and the SVR was 30%. Interferon/ribavirin non-responders demonstrated a SVR of 22%. Induction-dosing resulted in a greater first-phase HCV-RNA decay that, however, did not translate to better SVRs, presumably due to more dose modifications. High ALT, younger age, and second-phase viral kinetics were associated with SVR. Only sustained responders and relapse patients showed an improved liver histology.
Daily dosing of CIFN plus ribavirin may be a promising concept for selected non-responder patients before considering therapies which are anti-viral but not curative. However, motivation and compliance are requisites and a CIFN induction is not required.
Journal of Hepatology 03/2006; 44(2):291-301. · 9.26 Impact Factor
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ABSTRACT: Characterization of familial clusters of subjects with metabolic derangements predisposing to hepatic steatosis and nonalcoholic steatohepatitis could facilitate genomic studies to identify risk factors for their development. Dunnigan-type familial partial lipodystrophy (FPLD) is an autosomal dominantly inherited disorder caused by mutations in the LMNA gene. Affected subjects have loss of subcutaneous fat from the extremities and symptoms similar to those characterizing the metabolic syndrome, including insulin resistance and dyslipidemia. The goal of this study was to determine the prevalence of steatosis in subjects with FPLD.
We examined 18 subjects from six families with FPLD for mutations in LMNA and analyzed plasma lipid and serum glucose concentrations. Liver ultrasound and serum aminotransferase activities were used as indicators of steatosis or steatohepatitis. In two subjects, histological examination of hepatic tissue was performed.
All subjects had FPLD-causing mutations in LMNA. Plasma lipids were measured in 17 subjects, 16 of whom had hyperlipidemia and 14 presented with either documented insulin resistance or diabetes mellitus. Hepatic steatosis was present in 15 subjects who had ultrasound examinations and 9 of these had elevated serum aminotransferase activities. Liver biopsy confirmed steatosis in 2 subjects.
Hepatic steatosis is part of the clinical phenotype of FPLD. This familial disorder may provide a human metabolic model system to facilitate genomic and environmental studies to determine risk factors for hepatic steatosis and nonalcoholic steatohepatitis.
The American Journal of Gastroenterology 11/2005; 100(10):2218-24. · 7.28 Impact Factor
