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Iron Accumulation (iron + accumulation)
Kinds of Iron Accumulation Selected AbstractsLack of association of iron metabolism and Dupuytren's diseaseJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 4 2008J Hnanicek Abstract Background,Iron accumulation as seen in genetic haemochromatosis is a major cause of hepatic fibrogenesis. A link between chronic liver disease and Dupuytren's disease (DD) is well established, especially in alcoholics. Aim The aim of the present study was to test the hypothesis that iron accumulation might cause fibrosis of the palmar aponeurosis leading to DD. Patients and methods We examined iron metabolism, mutations of the HFE gene, serum cholesterol, alcohol consumption, presence of chronic liver disease, diabetes and history of severe manual work in a group of 90 patients who had undergone surgery for a severe form of DD. The tissue removed during surgery was histologically examined to confirm the diagnosis of DD. For a control group, we used 33 healthy subjects with similar profiles. Results The DD group consisted of 82 men and 8 women. Chronic liver disease was found in 27% of DD patients, compared with 6.1% of control subjects (P = 0.013). A history of hand traumatization was present in 33% of DD patients vs. 15% of control subjects (P = 0.048). Excessive alcohol consumption was present in 35.5% of DD patients compared with 15.1% of controls (P = 0.029). None of the other tested parameters, including the prevalence of HFE gene mutations, showed a significant difference between the two groups. Conclusions Iron accumulation does not play a major role in the pathogenesis of DD. However, sex, age, manual labour and alcohol consumption are risk factors for progression of DD. We observed a high incidence of chronic liver disease in patients with DD. [source] Hyperferritinemia and iron overload in type 1 Gaucher disease,AMERICAN JOURNAL OF HEMATOLOGY, Issue 7 2010Philip Stein Hyperferritinemia occurs in Gaucher disease but its clinical spectrum or its association with systemic iron overload and HFE mutations are not known. In 114 patients with Type 1 Gaucher disease, we determined serum ferritin, transferrin saturation and HFE genotype. The results were correlated with the extent of hepatosplenomegaly, overall Gaucher disease severity score index, and response to enzyme replacement therapy. In a subset of patients with radiological and/or laboratory evidence of systemic iron overload, liver biopsy was performed. There was a mean 3.7-fold elevation of serum ferritin over the upper limit of normal (ULN). Prior splenectomy was associated with most severe hyperferritinemia compared to patients with intact spleen (6.53 × ULN vs. 2.69 × ULN, P = 0.003). HFE genotyping revealed two patients homozygous for H63D mutation and 30% of patients heterozygote carriers of H63D mutation; no patients harbored C282Y mutation; there was no correlation of ferritin with HFE genotype. Ferritin level correlated with liver volume (Pearson correlation coefficient = 0.254, P = 0.035) and it was negatively correlated with hemoglobin (r = ,0.315, P = 0.004); there was no relationship with other indicators of Gaucher disease activity. Enzyme replacement therapy (ERT) resulted in amelioration of hyperferritinemia: 707 ± 898 ng/ml vs. 301 ± 310 ng/ml (P = 0.001), transferrin saturation remained normal. Three patients were suspected of clinical iron overload, confirmed on liver biopsy. Iron accumulation was variably noted in hepatocytes and Kupffer cells. There is a high prevalence of hyperferritinemia in Type 1 Gaucher disease that is associated with indicators of disease severity, reversed by ERT and is not related to HFE mutations. Am. J. Hematol. 2010. © 2010 Wiley-Liss, Inc. [source] Variable-field relaxometry of iron-containing human tissues: a preliminary studyCONTRAST MEDIA & MOLECULAR IMAGING, Issue 4 2009Aline Hocq Abstract Excess iron is found in brain nuclei from neurodegenerative patients (with Parkinson's, Alzheimer's and Huntington's diseases) and also in the liver and spleen of cirrhosis, hemochromatosis and thalassaemia patients. Ferritin, the iron-storing protein of mammals, is known to darken T2 -weighted MR images. Understanding NMR tissue behavior may make it possible to detect those diseases, to follow their evolution and finally to establish a protocol for non-invasive measurement of an organ's iron content using MRI methods. In this preliminary work, the MR relaxation properties of embalmed iron-containing tissues were studied as well as their potential correlation with the iron content of these tissues. Relaxometric measurements (T1 and T2) of embalmed samples of brain nuclei (caudate nucleus, dentate nucleus, globus pallidus, putamen, red nucleus and substantia nigra), liver and spleen from six donors were made at different magnetic fields (0.00023,14 T). The influence of the inter-echo time on transverse relaxation was also studied. Moreover, iron content of tissues was determined by inductively coupled plasma atomic emission spectroscopy. In brain nuclei, 1/T2 increases quadratically with the field and depends on the inter-echo time in CPMG sequences at high fields, both features compatible with an outer sphere relaxation theory. In liver and spleen, 1/T2 increases linearly with the field and depends on the inter-echo time at all fields. In our study, a correlation between 1/T2 and iron concentration is observed. Explaining the relaxation mechanism for these tissues is likely to require a combination of several models. The value of 1/T2 at high field could be used to evaluate iron accumulation in vivo. In the future, confirmation of those features is expected to be achieved from measurements of fresh (not embalmed) human tissues. Copyright © 2009 John Wiley & Sons, Ltd. [source] Different pathophysiological mechanisms of intramitochondrial iron accumulation in acquired and congenital sideroblastic anemia caused by mitochondrial DNA deletionEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 2 2006Thomas Matthes Abstract:, Sideroblastic anemias (SA) are characterized by iron accumulation in the mitochondria of erythroblasts. Although we have evidence of mitochondrial gene alterations in sporadic congenital cases, the origin of acquired forms [refractory anemia with ring sideroblasts (RARS)], is still largely unknown. Here, we report the analysis of respiratory chain function in a patient with a large mitochondrial deletion and in patients with RARS. A young boy with SA showed symptoms typical of a mitochondrial disease with metabolic acidosis, muscle weakness and cerebral involvement. His bone marrow DNA was analyzed for the presence of mitochondrial deletions. We found a new mitochondrial (mt)DNA deletion spanning 3614 bp and including all the mt genes encoding complex IV, plus ATPase 6 and 8, and several transfer (t)RNAs. All tissues analyzed (liver, skeletal muscle, brain, pancreas) showed a heteroplasmic distribution of this mutant DNA. Bone marrow homogenates were obtained from five patients with RARS and from three patients with normal bone marrow and respiratory chain function assayed by spectrophotometric analysis. Cytochrome c oxidase (CCO) activity was greatly reduced in the patient's bone marrow. In contrast, CCO activity and global respiratory chain function were conserved in patients with RARS. We conclude that deficient CCO activity secondary to mtDNA deletions is related to intramitochondrial iron accumulation, as in our patient or in those with Pearson's syndrome, whereas other mechanisms, e.g. nuclear DNA mutations, have to be proposed to be involved in the acquired forms of SA. [source] Type 3 hemochromatosis and , -thalassemia traitEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2004Alessia Riva Abstract: Type 3 hemochromatosis is a rare autosomal recessive disorder due to mutations of the TFR2 gene. We describe clinical, biochemical and histopathologic findings of a patient with type 3 hemochromatosis at presentation and during a follow-up of more than 20 yr and we evaluate the effect of an associated , -thalassemia trait on phenotypic expression. At the age of 33 yr the patient showed a marked iron overload and severe iron-related complications. After removal of 26 g of iron by subcutaneous deferoxamine infusion a marked clinical improvement was observed. Liver biopsies, performed at the age of 34 and 49 yr, indicate that in type 3 hemochromatosis there is a progressive hepatocellular iron accumulation from Rappaport's zone 1,3 and that iron loading in sinusoidal and portal macrophages occurs only in the more advanced stage. As observed in HFE hemochromatosis, the , -thalassemia trait seems to aggravate the clinical picture of patients lacking TFR2, favoring higher rates of iron accumulation probably by activation of the erythroid iron regulator. [source] Cellular iron status influences the functional relationship between microglia and oligodendrocytesGLIA, Issue 8 2006X. Zhang Abstract Previously, we have reported that there is a spatiotemporal relationship between iron accumulation in microglia and oligodendrocytes during normal development and in remyelination following injury. This in vivo observation has prompted us to develop a cell culture model to test the relationship between iron status of microglia and survival of oligodendrocytes. We found that conditioned media from iron-loaded microglia increases the survival of oligodendrocytes; but conditioned media from iron loaded activated microglia is toxic to oligodendrocytes. In the trophic condition, one of the proteins released by iron-loaded microglia is H-ferritin, and transfecting the microglia with siRNA for H-ferritin blocks the trophic response on oligodendrocytes. Lipopolysaccharide (LPS) activation decreases the amount of H-ferritin that is released from microglia and increases the release of the proinflammatory cytokines tumor necrosis factor-, and interleukin-1. LPS activation of iron-enriched microglia results in the activation of NF-kB and greater release of cytokines when compared with that of control microglia; whereas treating microglia with an iron chelator is associated with less NF-kB activation and less release of cytokines. These results indicate that microglia play an important role in iron homoeostasis and that their iron status can influence how microglia influence growth and survival of oligodendrocytes. The results further indicate that ferritin, released by microglia, is a significant source of iron for oligodendrocytes. © 2006 Wiley-Liss, Inc. [source] Role of hepatic iron in non-alcoholic steatohepatitisHEPATOLOGY RESEARCH, Issue 3 2009Yoshio Sumida Non-alcoholic fatty liver disease (NAFLD) includes a spectrum of clinical entities ranging from simple steatosis to non-alcoholic steatohepatitis (NASH) with possible evolution to cirrhosis and hepatocellular carcinoma. Iron is considered a putative element that interacts with oxygen radicals in inducing liver damage and fibrosis. The role of hepatic iron in the progression of NASH remains controversial, but in some patients, iron may have a role in the pathogenesis of NASH. Though genetic factors, insulin resistance, dysregulation of iron-regulatory molecules, erythrophagocytosis by Kupffer cells may be responsible for hepatic iron accumulation in NASH, exact mechanisms involved in iron overload remain to be clarified. Iron reduction therapy such as phlebotomy or dietary iron restriction may be promising in patients with NASH/NAFLD to reduce insulin resistance as well as serum transaminase activities. [source] Haemopexin affects iron distribution and ferritin expression in mouse brainJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 10 2009Noemi Morello Abstract Haemopexin (Hx) is an acute phase plasma glycoprotein, mainly produced by the liver and released into plasma where it binds heme with high affinity and delivers it to the liver. This system provides protection against free heme-mediated oxidative stress, limits access by pathogens to heme and contributes to iron homeostasis by recycling heme iron. Hx protein has been found in the sciatic nerve, skeletal muscle, retina, brain and cerebrospinal fluid (CSF). Recently, a comparative proteomic analysis has shown an increase of Hx in CSF from patients with Alzheimer's disease, thus suggesting its involvement in heme detoxification in brain. Here, we report that Hx is synthesised in brain by the ventricular ependymal cells. To verify whether Hx is involved in heme scavenging in brain, and consequently, in the control of iron level, iron deposits and ferritin expression were analysed in cerebral regions known for iron accumulation. We show a twofold increase in the number of iron-loaded oligodendrocytes in the basal ganglia and thalamus of Hx-null mice compared to wild-type controls. Interestingly, there was no increase in H- and L-ferritin expression in these regions. This condition is common to several human neurological disorders such as Alzheimer's disease and Parkinson's disease in which iron loading is not associated with an adequate increase in ferritin expression. However, a strong reduction in the number of ferritin-positive cells was observed in the cerebral cortex of Hx-null animals. Consistent with increased iron deposits and inadequate ferritin expression, malondialdehyde level and Cu,Zn superoxide dismutase-1 expression were higher in the brain of Hx-null mice than in that of wild-type controls. These data demonstrate that Hx plays an important role in controlling iron distribution within brain, thus suggesting its involvement in iron-related neurodegenerative diseases. [source] Restriction of dietary calories, fat and iron improves non-alcoholic fatty liver diseaseJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 4 2007Mika Yamamoto Abstract Background:, The pathogenesis of non-alcoholic steatohepatitis (NASH) is unclear. Recent studies suggested that oxidative stress plays an important role in the mechanism of NASH. Excessive accumulation of iron in the liver causes oxidative stress. The aim of the present study was to evaluate the grade of hepatic iron accumulation and the therapeutic response to restriction of calories, fat and iron in patients with non-alcoholic fatty liver disease (NAFLD). Methods:, Twenty-seven NAFLD patients were enrolled. The patients were categorized into two groups: 17 patients with NASH and 10 with simple steatosis. Twelve NAFLD patients (NASH, n = 9; simple steatosis, n = 3) were given a dietary prescription including restriction of energy, fat and iron. Results:, Positive iron staining was observed in 71% and 50% of patients with NASH and simple steatosis, respectively. The average energy intake, fat energy fraction and iron intake decreased significantly 6 months after the beginning of the diet in all patients. In addition, the levels of serum transaminase and ferritin were significantly decreased. Conclusion:, Dietary restriction of calories, fat and iron improved NAFLD. Reduced serum ferritin levels appear to reduce oxidative stress in the liver. [source] Intellectual and adaptive behaviour functioning in pantothenate kinase-associated neurodegenerationJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 6 2007K. Freeman Abstract Background Pantothenate kinase-associated neurodegeneration (PKAN), an extremely rare autosomal recessive disorder resulting in iron accumulation in the brain, has a diverse phenotypic expression. Based on limited case studies of one or two patients, intellectual impairment is considered part of PKAN. Investigations of cognitive functioning have utilized specific neuropsychological tests, without attention to general intellectual skills or adaptive behaviour. Methods Sixteen individuals with PKAN completed measures of global intellectual functioning, and participants or care providers completed measures of adaptive behaviour skills and day-to-day functional limitations. Clinicians provided global ratings of condition severity. Results Testing with standardized measures documented varied phenotypic expression, with general cognitive skills and adaptive behaviour ranging from high average to well below average. Age of disease onset correlated with measures of intellectual functioning, adaptive functioning and disease severity. Conclusions Findings support previously described clinical impressions of varied cognitive impairment and the association between age of onset and impairment. Further, they add important information regarding the natural history of the disease and suggest assessment strategies for use in treatment trials. [source] Divalent metal transporter 1 up-regulation is involved in the 6-hydroxydopamine-induced ferrous iron influxJOURNAL OF NEUROSCIENCE RESEARCH, Issue 14 2007Ning Song Abstract The reasons underlying the high iron content found in the substantia nigra (SN) of Parkinson's disease (PD) are largely unknown. We suppose, based on our previous studies, that the newly discovered iron transporter divalent metal transporter 1 (DMT1) might be involved in this SN iron accumulation process. To investigate this, we first observed the cellular expression of DMT1 in rat SN, both with the iron response element (+IRE) and without the IRE (,IRE) forms. The results showed that both forms of DMT1 were expressed on neurons, astrocytes, and microglia but not on oligodendrocytes. We further observed the relationship between the increased iron influx and DMT1 expression in 6-hydroxydopamine (6-OHDA)-treated C6 cells. 6-OHDA (10 ,mol/liter) caused a significant increase in ferrous iron influx, with the increased expression of DMT1+IRE, both in protein and in mRNA levels, whereas no change was observed for DMT1,IRE. To clarify further that the increased expression of DMT1 was not due to the increased intracellular iron content, C6 cells were overloaded with ferric ammonium citrate (100 ,g/ml). Decreased expression of both forms of DMT1 was observed. Our data suggest that DMT1 is highly expressed in rat SN in a cell-specific manner. Increased DMT1+IRE expression is the mechanism behind ferrous iron influx induced by 6-OHDA treatment in C6 cells. This may give some evidence for the involvement of DMT1 in the iron accumulation in PD. © 2007 Wiley-Liss, Inc. [source] Ferroportin q248h, Dietary Iron, and Serum Ferritin in Community African-Americans With Low to High Alcohol ConsumptionALCOHOLISM, Issue 11 2008Victor R. Gordeuk Background:, Alcohol consumption is associated with increased iron stores. In sub-Saharan Africa, high dietary ionic iron and the ferroportin Q248H allele have also been implicated in iron accumulation. We examined the associations of ferroportin Q248H, alcohol and dietary iron with serum ferritin, aspartate aminotransaminase (AST) and alanine aminotransaminase (ALT) concentrations in African-Americans. Methods:, Inner-city African-Americans (103 men, 40 women) were recruited from the community according to reported ingestion of >4 alcoholic drinks/d or <2/wk. Typical daily heme iron, nonheme iron and alcohol were estimated using University of Hawaii's multiethnic dietary questionnaire. Based on dietary questionnaire estimates we established categories of < versus ,56 g alcohol/d, equivalent to 4 alcoholic drinks/d assuming 14 g alcohol per drink. Results:, Among 143 participants, 77% drank <56 g alcohol/d and 23%,56 g/d as estimated by the questionnaire. The prevalence of ferroportin Q248H was 23.3% with alcohol >56 g/d versus 7.5% with lower amounts (p = 0.014). Among subjects with no history of HIV disease, serum ferritin concentration had positive relationships with male gender (p = 0.041), alcohol consumption (p = 0.021) and ALT concentration (p = 0.0001) but not with dietary iron intake or ferroportin Q248H. Serum AST and ALT concentrations had significant positive associations with male gender and hepatitis C seropositivity but not with alcohol or dietary iron intake or ferroportin Q248H. Conclusions:, Our findings suggest a higher prevalence of ferroportin Q248H with greater alcohol consumption, and this higher prevalence raises the possibility that the allele might ameliorate the toxicity of alcohol. Our results suggest that alcohol but not dietary iron contributes to higher body iron stores in African-Americans. Studies with larger numbers of participants are needed to further clarify the relationship of ferroportin Q248H with the toxicity of alcohol consumption. [source] Effects of Alcohol Consumption on Iron Metabolism in Mice with Hemochromatosis MutationsALCOHOLISM, Issue 1 2007Jonathan M. Flanagan Background: Alcoholic liver disease is associated with increased hepatic iron accumulation. The liver-derived peptide hepcidin is the central regulator of iron homeostasis and recent animal studies have demonstrated that exposure to alcohol reduces hepcidin expression. This down-regulation of hepcidin in vivo implies that disturbed iron sensing may contribute to the hepatosiderosis seen in alcoholic liver disease. Alcohol intake is also a major factor in expression of the hemochromatosis phenotype in patients homozygous for the C282Y mutation of the HFE gene. Methods: To assess the effect of alcohol in mice with iron overload, alcohol was administered to mice with disrupted Hfe and IL-6 genes and Tfr2 mutant mice and their respective 129x1/SvJ, C57BL/6J, and AKR/J wild-type congenic strains. Iron absorption, serum iron levels, and hepcidin expression levels were then measured in these mice compared with water-treated control mice. Results: Alcohol was shown to have a strain-specific effect in 129x1/SvJ mice, with treated 129x1/SvJ mice showing a significant increase in iron absorption, serum iron levels, and a corresponding decrease in hepcidin expression. C57BL/6J and AKR/J strain mice showed no effect from alcohol treatment. 129x1/SvJ mice heterozygous or homozygous for the Hfe knockout had a diminished response to alcohol. All 3 strains were shown to have high blood alcohol levels. Conclusions: The effect of alcohol on iron homeostasis is dependent on the genetic background in mice. In an alcohol-susceptible strain, mutation of the Hfe gene diminished the response of the measured iron indices to alcohol treatment. This indicates that either maximal suppression of hepcidin levels had already occurred as a result of the Hfe mutation or that Hfe was a component of the pathway utilized by EtOH in suppressing hepcidin production and increasing iron absorption. [source] Induction of Transferrin Receptor by Ethanol in Rat Primary Hepatocyte CultureALCOHOLISM, Issue 2004Masako Suzuki Background: It is not uncommon for alcoholics to have iron accumulation in the liver, a condition that may contribute to the development of alcoholic liver disease. Recently, we reported that the expression of transferrin receptor, which mediates cellular iron uptake, was increased in hepatocytes in patients with alcoholic liver disease. To elucidate the mechanism of the iron accumulation in hepatocytes in such disease, we examined whether ethanol exposure induced the transferrin receptor expression and increased the cellular iron uptake. Methods: Rat primary hepatocytes were isolated and cultured in the presence of 20 ,mol/liter of iron and 25 mmol/liter of ethanol. Results: Ethanol exposure to the hepatocytes demonstrated an ,2-fold increase in transferrin receptor expression for 24 hr, shown by Western blot analysis and 35S-methionine metabolic labeling, 19% increase in 59Fe-transferrin uptake by hepatocytes, and 20% increase in activity of iron regulatory protein examined by band shift assay. Conclusion: Ethanol exposure induced the transferrin receptor expression, partially through the activation of iron regulatory protein, and increased the transferrin-bound iron uptake in rat hepatocyte cultures. The induction of transferrin receptor by ethanol might be one of the mechanisms of iron accumulation in the hepatocytes in alcoholic liver disease. [source] Lack of association of iron metabolism and Dupuytren's diseaseJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 4 2008J Hnanicek Abstract Background,Iron accumulation as seen in genetic haemochromatosis is a major cause of hepatic fibrogenesis. A link between chronic liver disease and Dupuytren's disease (DD) is well established, especially in alcoholics. Aim The aim of the present study was to test the hypothesis that iron accumulation might cause fibrosis of the palmar aponeurosis leading to DD. Patients and methods We examined iron metabolism, mutations of the HFE gene, serum cholesterol, alcohol consumption, presence of chronic liver disease, diabetes and history of severe manual work in a group of 90 patients who had undergone surgery for a severe form of DD. The tissue removed during surgery was histologically examined to confirm the diagnosis of DD. For a control group, we used 33 healthy subjects with similar profiles. Results The DD group consisted of 82 men and 8 women. Chronic liver disease was found in 27% of DD patients, compared with 6.1% of control subjects (P = 0.013). A history of hand traumatization was present in 33% of DD patients vs. 15% of control subjects (P = 0.048). Excessive alcohol consumption was present in 35.5% of DD patients compared with 15.1% of controls (P = 0.029). None of the other tested parameters, including the prevalence of HFE gene mutations, showed a significant difference between the two groups. Conclusions Iron accumulation does not play a major role in the pathogenesis of DD. However, sex, age, manual labour and alcohol consumption are risk factors for progression of DD. We observed a high incidence of chronic liver disease in patients with DD. [source] Influence of Helicobacter pylori infection on iron accumulation in hepatitis CLIVER INTERNATIONAL, Issue 7 2006Yoshio Sumida Abstract: Goal: Iron may play a role in the pathogenesis of chronic hepatitis C. Helicobacter pylori (Hp) infection was recently associated with iron-deficiency anemia. We examined the influence of Hp infection on hepatic iron accumulation in hepatitis C. Methods: Ninety-five hepatitis C virus (HCV)-RNA-positive patients, including 60 chronic hepatitis, 17 cirrhosis and 18 hepatocellular carcinoma as well as 95 age- and sex-matched normal subjects without HCV infection as control, were studied. Liver biopsies were also obtained from 44 HCV-infected patients. Serum Hp antibodies were measured by an enzyme-linked immunosorbent assay and clinical data, including iron parameters and histological findings, were compared between Hp-positive and -negative HCV-infected patients. Results: The percentage of serum Hp antibodies was lower in HCV-infected patients than in controls (52/95 (54.7%) vs. 68/95 (71.6%); P<0.05). HCV-infected patients had higher serum ferritin levels than controls (120 [2.8,1700] vs. 58 [2.2,420] ng/ml; P<0.0001). In HCV-infected patients, the serum ferritin levels (medians and [ranges]) in Hp-positive patients were significantly lower than those of Hp-negative patients (99 [8.5,770] vs. 150 [2.8,1700] ng/ml; P<0.05). The grades of hepatic iron deposit in Hp-positive patients were significantly lower than those in Hp-negative patients (P<0.01). Conclusions: Hp infection may at least partly affect hepatic iron accumulation in HCV-related liver diseases. [source] Indian-subcontinent NBIA: Unusual phenotypes, novel PANK2 mutations, and undetermined genetic forms ,MOVEMENT DISORDERS, Issue 10 2010Annu Aggarwal MD Abstract Neurodegeneration with brain iron accumulation (NBIA) is etiologically, clinically, and by imaging a heterogeneous group including NBIA types 1 [pantothenate kinase-associated neurodegeneration (PKAN)] and 2 (PLA2G6 -associated neurodegeneration), neuroferritinopathy, and aceruloplasminaemia. Data on genetically defined Indian-subcontinent NBIA cases are limited. We report 6 patients from the Indian-subcontinent with a movement disorder and MRI basal ganglia iron deposition, compatible with diagnosis of an NBIA syndrome. All patients were screened for abnormalities in serum ceruloplasmin and ferritin levels and mutations in NBIA-associated genes [pantothenate kinase 2 (PANK2), PLA2G6 and ferritin light chain (exon 4)]. We present clinical, imaging and genetic data correlating phenotype,genotype relations. Four patients carried PANK2 mutations, two of these were novel. The clinical phenotype was mainly dystonic with generalized dystonia and marked orobulbar features in the 4 adolescent-onset cases. One of the four had a late-onset (age 37) unilateral jerky postural tremor. His mutation, c.1379C>T, appears associated with a milder phenotype. Interestingly, he developed the eye-of-the-tiger sign only 10 years after onset. Two of the six presented with adult-onset levodopa (L -dopa)-responsive asymmetric re-emergent rest tremor, developing L -dopa-induced dyskinesias, and good benefit to deep brain stimulation (in one), thus resembling Parkinson's disease (PD). Both had an eye-of-the-tiger sign on MRI but were negative for known NBIA-associated genes, suggesting the existence of further genetic or sporadic forms of NBIA syndromes. In conclusion, genetically determined NBIA cases from the Indian subcontinent suggest presence of unusual phenotypes of PANK2 and novel mutations. The phenotype of NBIA of unknown cause includes a PD-like presentation. © 2010 Movement Disorder Society [source] ATP13A2 mutations (PARK9) cause neurodegeneration with brain iron accumulation,MOVEMENT DISORDERS, Issue 8 2010Susanne A. Schneider MD Abstract Kufor Rakeb disease (KRD, PARK9) is an autosomal recessive extrapyramidal-pyramidal syndrome with generalized brain atrophy due to ATP13A2 gene mutations. We report clinical details and investigational results focusing on radiological findings of a genetically-proven KRD case. Clinically, there was early onset levodopa-responsive dystonia-parkinsonism with pyramidal signs and eye movement abnormalities. Brain MRI revealed generalized atrophy and putaminal and caudate iron accumulation bilaterally. Our findings add KRD to the group of syndromes of neurodegeneration with brain iron accumulation (NBIA). KRD should be considered in patients with dystonia-parkinsonism with iron on brain imaging and we suggest classifying as NBIA type 3. © 2010 Movement Disorder Society [source] Iron metabolism in Parkinsonian syndromesMOVEMENT DISORDERS, Issue 9 2006Daniela Berg MD Abstract Growing evidence suggests an involvement of iron in the pathophysiology of neurodegenerative diseases. Several of the diseases are associated with parkinsonian syndromes, induced by degeneration of basal ganglia regions that contain the highest amount of iron within the brain. The group of neurodegenerative disorders associated with parkinsonian syndromes with increased brain iron content can be devided into two groups: (1) parkinsonian syndromes associated with brain iron accumulation, including Parkinson's disease, diffuse Lewy body disease, parkinsonian type of multiple system atrophy, progressive supranuclear palsy, corticobasal ganglionic degeneration, and Westphal variant of Huntington's disease; and (2) monogenetically caused disturbances of brain iron metabolism associated with parkinsonian syndromes, including aceruloplasminemia, hereditary ferritinopathies affecting the basal ganglia, and panthotenate kinase associated neurodegeneration type 2. Although it is still a matter of debate whether iron accumulation is a primary cause or secondary event in the first group, there is no doubt that iron-induced oxidative stress contributes to neurodegeneration. Parallels concerning pathophysiological as well as clinical aspects can be drawn between disorders of both groups. Results from animal models and reduction of iron overload combined with at least partial relief of symptoms by application of iron chelators in patients of the second group give hope that targeting the iron overload might be one possibility to slow down the neurodegenerative cascade also in the first group of inevitably progressive neurodegenerative disorders. © 2006 Movement Disorder Society [source] Redox active iron accumulation in aceruloplasminemiaNEUROPATHOLOGY, Issue 5 2008Luis F. Gonzalez-Cuyar Aceruloplasminemia is an autosomal recessive disorder characterized by a ceruloplasmin gene mutation and defective or absent ceruloplasmin function. Because ceruloplasmin functions in iron transport and storage, aceruloplasminemia leads to excessive iron accumulation systemically and within the CNS. The type and form of iron deposited is unclear and while oxidative stress was hypothesized as a potential mechanism of cytotoxicity in this disorder, direct evidence linking oxidative stress to the underlying genetic defect has not been provided. To address these issues, we studied autopsy brain tissue from two subjects with genetically confirmed aceruloplasminemia using an assay developed in our laboratory for redox-active iron assessment. We found iron deposited in perivascular areas, localizing to terminal astrocytic processes and further showed that this iron was redox active. These data are consistent with the concept that oxidative stress, driven by heavy metal accumulation, represents the primary cellular cytotoxic process, accounting for neuronal damage in affected brain regions. As such, aceruloplasminemia is an excellent model of transition metal-driven oxidative stress and neurodegeneration. [source] Microarray analysis of liver gene expression in iron overloaded patients with sickle cell anemia and beta-thalassemia,AMERICAN JOURNAL OF HEMATOLOGY, Issue 6 2009Jonathan M. Flanagan Chronic transfusion therapy is used clinically to supply healthy erythrocytes for patients with sickle cell anemia (SCA) or beta-thalassemia major (TM). Despite the benefits of red blood cell transfusions, chronic transfusions lead to iron accumulation in key tissues such as the heart, liver, and endocrine glands. Transfusion-acquired iron overload is recognized as a cause of morbidity and mortality among patients receiving chronic transfusions. At present, there is little understanding of molecular events that occur during transfusional iron loading and the reasons for the large inter-individual variation observed clinically in transfusion-acquired iron accumulation. To address these issues, we examined whether any liver-expressed genes in SCA or TM patients with transfusional iron overload were associated with the degree of iron accumulation. Specifically, we performed microarray analysis on liver biopsy specimens comparing SCA patients with mild or severe iron overload and also compared SCA with TM patients. Fifteen candidate genes were identified with significantly differential expression between the high and low liver iron concentrations. SCA patients and 20 candidate genes were detected between the SCA and TM patient comparison. Subsequent quantitative PCR experiments validated 12 candidate genes; with GSTM1, eIF5a, SULF2, NTS, and HO-1 being particularly good prospects as genes that might affect the degree of iron accumulation. Future work will determine the baseline expression of these genes prior to transfusional iron overload and elucidate the full impact of these genes on the inter-individual variation observed clinically in transfusion-acquired iron accumulation. Am. J. Hematol. 2009. © 2009 Wiley-Liss, Inc. [source] Distinct physiological responses of two rice cultivars subjected to iron toxicity under field conditionsANNALS OF APPLIED BIOLOGY, Issue 2 2009R.J. Stein Abstract Iron toxicity is recognised as the most widely distributed nutritional disorder in lowland and irrigated rice, derived from the excessive amounts of ferrous ions generated by the reduction of iron oxides in flooded soils. Rice cultivars with variable degrees of tolerance to iron toxicity have been developed, and cultural practices such as water management and fertilisation can be used to reduce its negative impact. However, because of the complex nature of iron toxicity, few physiological data concerning tolerance mechanisms to excess iron in field conditions are available. To analyse the physiological responses of rice to iron excess in field conditions, two rice cultivars with distinct tolerance to iron toxicity [BR-IRGA 409 (susceptible) and IRGA 420 (tolerant)] were grown in two areas, with a well-established history of iron toxicity (in Camaquć, RS, Brazil) and without iron toxicity (in Cachoeirinha, RS, Brazil). Plants from the susceptible cultivar grown in the iron-toxic site showed lower levels of chlorophylls and soluble proteins (together with higher carbonyl levels) indicating photooxidative and oxidative damage. The toxic effects observed were because of the accumulation of high levels of iron and not because of any indirectly induced shoot deficiency of other nutrients. Higher activities of antioxidative enzymes were also observed in leaves of plants from the susceptible cultivar only in the iron-toxic site, probably as a result of oxidative stress rather than because of specific involvement in a tolerance mechanism. There was no difference between cultivars in iron accumulation in the symplastic and apoplastic space of leaves, with both cultivars accumulating 85,90% of total leaf iron in the symplast. However, susceptible plants accumulated higher levels of iron in low-molecular-mass fractions than tolerant plants. The accumulation of iron in the low-molecular-mass fraction probably has a direct influence on iron toxicity, and the adaptive strategy of tolerant plants may rely on their capacity to buffer the iron amounts present in the low mass fraction, a new parameter to be considered when evaluating tolerance to iron excess in field-cultivated rice plants. [source] Characterization of PLA2G6 as a locus for dystonia-parkinsonismANNALS OF NEUROLOGY, Issue 1 2009Coro Paisan-Ruiz PhD Background Although many recessive loci causing parkinsonism dystonia have been identified, these do not explain all cases of the disorder. Methods We used homozygosity mapping and mutational analysis in three individuals from two unrelated families who presented with adult-onset levodopa-responsive dystonia-parkinsonism, pyramidal signs and cognitive/psychiatric features, and cerebral and cerebellar atrophy on magnetic resonance imaging but absent iron in the basal ganglia. Results We identified areas of homozygosity on chromosome 22 and, subsequently, PLA2G6 mutations. Interpretation PLA2G6 mutations are associated with infantile neuroaxonal dystrophy and have been reported previously to cause early cerebellar signs, and the syndrome was classified as neurodegeneration with brain iron accumulation (type 2). Our cases have neither of these previously pathognomic features. Thus, mutations in PLA2G6 should additionally be considered in patients with adult-onset dystonia-parkinsonism even with absent iron on brain imaging. Ann Neurol 2008 [source] Iron in neuronal function and dysfunctionBIOFACTORS, Issue 2 2010Gabriela A. Salvador Abstract Iron (Fe) is an essential element for many metabolic processes, serving as a cofactor for heme and nonheme proteins. Cellular iron deficiency arrests cell growth and leads to cell death; however, like most transition metals, an excess of intracellular iron is toxic. The ability of Fe to accept and donate electrons can lead to the formation of reactive nitrogen and oxygen species, and oxidative damage to tissue components; contributing to disease and, perhaps, aging itself. It has also been suggested that iron-induced oxidative stress can play a key role in the pathogenesis of several neurodegenerative diseases. Iron progressively accumulates in the brain both during normal aging and neurodegenerative processes. However, iron accumulation occurs without the concomitant increase in tissue ferritin, which could increase the risk of oxidative stress. Moreover, high iron concentrations in the brain have been consistently observed in Alzheimer's disease (AD) and Parkinson's disease (PD). In this regard, metalloneurobiology has become extremely important in understanding the role of iron in the onset and progression of neurodegenerative diseases. Neurons have developed several protective mechanisms against oxidative stress, among them the activation of cellular signaling pathways. The final response will depend on the identity, intensity, and persistence of the oxidative insult. The characterization of the mechanisms involved in high iron induced in neuronal dysfunction and death is central to understanding the pathology of a number of neurodegenerative disorders. [source] Molecular characterization of six unrelated Italian patients affected by pyrimidine 5,-nucleotidase deficiencyBRITISH JOURNAL OF HAEMATOLOGY, Issue 5 2003Paola Bianchi Summary. Pyrimidine 5,-nucleotidase deficiency is a rare autosomal recessive disorder characterized by haemolytic anaemia, marked basophilic stippling and accumulation of pyrimidine nucleotides within the erythrocytes. The gene encoding for this enzyme (P5,N-1) has been cloned recently, and seven mutations have so far been identified in 11 unrelated families. We describe the haematological and molecular characteristics of six unrelated Italian patients affected by pyrimidine 5,-nucleotidase deficiency (one from northern and five from southern Italy). The sequence of the complete P5,N-1 gene showed the presence of four different new mutations: a missense mutation AAT,AGT at codon 190 (Asn,Ser), one splicing mutation (IVS9-1 g-c) and two frameshift mutations, DelG576 and InsGG743. Although the molecular defect was homozygous in all patients but one, parents' consanguinity could be confirmed in only one case. InsGG743 was detected in two cases, and DelG576 was found in three patients originating from southern Italy, suggesting a possible geographical distribution of the genetic defect. Haematological data showed the presence of peripheral spherocytosis in all cases, although only one had a concomitant membrane defect. An increase in serum ferritin levels was observed in the splenectomized patients, suggesting that the iron status of these subjects should be monitored and that they should be investigated for potential additional risk factors for iron accumulation. [source] | |||||||||||||||||||||||||||||||