Clinical manifestations and gene mutation of X-linked adrenoleukodystrophy: case analysis / 中华内分泌代谢杂志

The clinical manifestations, biochemical parameters and imaging examination, genetic test results, and treatment of 3 cases of X-linked adrenoleukodystrophy(X-ALD) patients were reviewed and analyzed, and the structure of adrenoleukodystrophy protein(ALDP) was analyzed. All 3 patients were male. Patients 1 and 2 were childhood cerebral ALD(CCALD), patients 3 was adrenomyeloneuropathy(AMN), and all of them were misdiagnosed at early stage. Brain magnetic resonance imaging(MRI), and hematologic examinations showed the neurological demyelination of X-ALD, adrenocortical insufficiency, and accumulation of very long chain fatty acids(VLCFAs). Sequencing of ABCD1 gene revealed 3 new pathogenic mutations[c.910delins22(p.A304delins8), c. 887A>C(p.Y296S), and c. 1451_1481del(p.P484fs)], which affected the key structure of ALDP and led to the disease. Patients 1 and 2 received hematopoietic stem cell transplantation, and their condition continued to progress after surgery. Patient 3 was in stable condition. The misdiagnosis rate of X-ALD is high, clinicians should be vigilant. In this study, 3 new mutations were found, which expanded the ABCD1 gene mutation spectrum in patients with X-ALD. It is important to note that early identification and early diagnosis of X-ALD should be made to reduce misdiagnosis and mistreatment.

Protective effect of N-acetyl-L-cysteine and rosuvastatin against oxidative stress in fibroblasts from asymptomatic patients with X-ALD: a preliminary study

Introduction: Several studies in the literature have evaluated the role of oxidative stress and adjuvant therapies for X-linked adrenoleukodystrophy (X-ALD). Here, we investigated whether n-acetyl-L-cysteine (NAC) and rosuvastatin (RSV) could influence the generation of reactive species, redox status and nitrative stress in fibroblasts from asymptomatic patients with X-ALD. Methods: Skin biopsy samples were cultured and treated for 2 hours (37 °C) with NAC and RSV. Results: X-ALD fibroblasts generated high levels of reactive oxygen species. These levels were significantly lower in fibroblasts treated with NAC and RSV relative to untreated samples. The X-ALD fibroblasts from asymptomatic patients also had higher catalase activity, and only NAC was able to increase enzyme activity in the samples. Conclusions: Our results indicated that NAC and RSV were able to improve oxidative stress parameters in fibroblasts from asymptomatic patients with X-ALD, showing that adjuvant antioxidant therapy may be a promising treatment strategy for asymptomatic patients with this disease. (AU)

Increased levels of hexacosanoic acid in the brain of Winstar rats: a behavioral study

Introduction: X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal metabolic disorder associated with mutations in the ATP-binding cassette sub-family D member1 (ABCD1) gene. Practically all male patients with X-ALD develop adrenocortical insufficiency during childhood and progressive myelopathy and peripheral neuropathy in adulthood. However, some male patients develop a fatal cerebral demyelinating disease named cerebral adrenoleukodystrophy. Although the exact mechanisms underlying brain damage in X-ALD are still poorly elucidated, it is known that hexacosanoic acid (C26:0) accumulation represents a hallmark in the pathogenesis of this disease. In this study, we examined whether an overload of C26:0 injected in Wistar rats was capable of causing behavioral changes in these animals. Methods: Egg lecithin in ethanol was dried under a nitrogen stream and mixed with C26:0 methyl ester. Male Wistar rats at 2-3 weeks of age were obtained from Universidade Federal do Rio Grande do Sul (UFRGS), divided into 8 groups, and submitted to an open field test. We then analyzed line crossings (locomotion and exploration), rearing (orienting and investigatory responses), grooming (anxiety manifestation), and latency to move for each animal. Results: Animals subjected to C26:0 administration presented fewer crossings and rearing episodes and a higher latency to move 45 minutes after C26:0 injection. The present work yields experimental evidence that C26:0, the main accumulated metabolite in X-ALD, can cause behavioral alterations in rats such as the impairment of locomotion and exploratory capabilities, as well as a reduction in orienting and investigatory responses. Conclusion: Although our results are preliminary, they are extremely important for future studies that investigate C26:0 accumulation and locomotor impairment in patients with X-ALD. (AU)

Genetic analysis of a pedigree affected with X-linked adrenoleukodystrophy / 中华医学遗传学杂志

Objective@#To explore the genetic basis for a pedigree affected with X-linked adrenoleukodystrophy presenting as spastic paraplegia of the lower limbs.@*Methods@#Genomic DNA was extracted from peripheral blood samples of the patient and his mother. Potential variant was detected with a panel for genes associated with spastic paraplegia. Candidate variant was verified by PCR and Sanger sequencing.@*Results@#Both the proband and his mother presented with walking difficulty. A previously known variant, c. 623T>A (p.V208E), was identified in the ABCD1 gene mapped on chromosome X in both.@*Conclusion@#X-link adrenoleukodystrophy should be taken into account as a possible diagnosis for this pedigree.

Research progress in diagnosis and treatment of female heterozygotes with X-linked adrenoleukodystrophy / 中华实用儿科临床杂志

X-linked adrenoleukodystrophy is the most common peroxisomal disorder,which belongs to single peroxidase enzyme deficiency disease.It is caused by mutations in the ABCDI gene and alterations in peroxisomal beta-oxidation of long chain fatty acid in plasma and tissues.It manifests a wide range of phenotypes in male and it has been frequently discussed,in which progressive myelopathy is the most common.For X-linked recessive inheritance,female heterozygotes are always thought to be nonpathogenic.There have been only limited studies specifically focused on the phenotype of female heterozygotes,while,these patients also need further study.This article discusses the clinical manifestations,diagnosis and treatment of female heterozygotes with X-linked adrenoleukodystrophy,to enhance people's understanding of clinical diagnosis and treatment,and provide the basis for accurate prognosis assess-ment and diagnosis.

Adrenoleucodistrofia ligada al X: presentación de tres casos. Importancia del diagnóstico precoz / X-linked adrenoleukodystrophy: a report of three cases. The importance of early diagnosis

La adrenoleucodistrofia ligada al X es el trastorno peroxisomal más común. Se debe a mutaciones en el gen ABCD1, lo que ocasiona un acúmulo de ácidos grasos saturados de cadena muy larga en el suero, la corteza adrenal y la sustancia blanca del sistema nervioso central. La clínica se caracteriza por deterioro neurològico e insuficiencia suprarrenal con un pronóstico devastador. Se presenta un primer caso clínico de adrenoleucodistrofia ligada al X con evolución fatal que permitió identificar a dos familiares asintomáticos e instaurar un tratamiento preventivo. Aunque, en la actualidad, no existe un tratamiento curativo definitivo, hay que destacar la importancia del estudio familiar de pacientes en situación de riesgo para poder instaurar un tratamiento preventivo precoz y dar un asesoramiento genético adecuado.

X-linked adrenoleukodystrophy is the most common peroxisomal disorder. This disease is caused by a defect in the ABCD1 gen. Saturated very long chain fatty acids are accumulated in serum, adrenal cortex and central nervous system white matter. The clinical spectrum is characterized by progressive neurological dysfunction and adrenal insufficiency with a devastating prognosis. We report a first case of X-linked adrenoleukodystrophy with fatal evolution which identified two asymptomatic family members and established a preventive treatment. Although there is no definitive cure, we stress the importance of family study and evaluation of the individual in situation of risk to establish an early preventive treatment and to give in each particular situation suitable professional advice.

In vitro effect of N-acetyl-L-cysteine on glutathione and sulfhydryl levels in X-linked adrenoleukodystrophy patients

Introduction: Recent evidence shows that oxidative stress seems to be related with the pathophysiology of X-linked adrenoleukodystrophy (X-ALD), a neurodegenerative disorder. Methods: In the present study, the in vitro effect of N-acetyl-L-cysteine (NAC) on glutathione (GSH) and sulfhydryl levels in X-ALD patients was evaluated. Results: A significant reduction of GSH and sulfhydryl content was observed in X-ALD patients compared to the control group. Furthermore, 5 mM of NAC, in vitro, led to an increase in GSH content and sulfhydryl groups in these patients. Conclusion: These data probably indicate that an adjuvant therapy with the antioxidant NAC could improve the oxidative imbalance in X-ALD patients(AU)

Diagnosis and managements of X-linked adrenoleukodystrophy / 中华实用儿科临床杂志

Adrenoleukodystrophy (ALD,OMIM# 300100) is one of the most common peroxisomal disease.It is a kind of X-linked genetic disorder.The disease is caused by mutations in the ABCD1 gene that encodes the peroxisomal membrane protein(ALDP).A defect in ALDP results in very long-chain fatty acids can not be transported from the cytosol into the peroxisome and impaired accumulation of very long chain fatty acid (VLCFA)-CoA esters in the white matter of the brain,the spinal cord and adrenal cortex.The clinical spectrum in males with X-ALD ranges from isolated adrenocortical insufficiency and slowly progressive myelopathy to devastating cerebral demyelination.Corticosteroid replacement therapy is essential and life saving treatment,bone marrow transplantation (BMT) is an option for boys and adolescents in early stages.This review focus on the genetic pathology,diagnosis and managements of patients with X-ALD and provides a guideline for clinicians.

Adrenoleucodistrofia ligada ao X: correlação entre o escore de Loes e parâmetros do tensor de difusão / X-linked adrenoleukodystrophy: correlation between Loes score and diffusion tensor imaging parameters

Objetivo: Avaliar a correlação dos parâmetros do tensor de difusão com o escore de Loes e se os parâmetros do tensor de difusão poderiam indicar alterações estruturais precoces. Materiais e Métodos: As medidas do tensor de difusão foram obtidas em 30 exames de 14 pacientes com adrenoleucodistrofia ligada ao X e foram correlacionadas com o escore de Loes. Um grupo controle de 28 pacientes masculinos foi avaliado para estabelecer medidas do tensor de difusão pareadas por idade. Análises estatísticas intra e interobservador foram feitas. Resultados: As medidas do tensor de difusão apresentam forte correlação com o escore de Loes segundo o coeficiente de Pearson (r), com valores de –0,86, 0,89, 0,89 e 0,84 para a fração de anisotropia e difusibilidades média, radial e axial (p < 0,01). A análise da mudança nas medidas do tensor de difusão no estágio inicial da doença indica que os valores de difusibilidades média e radial podem ajudar a predizer a progressão da doença. Conclusão: As medidas de parâmetros do tensor de difusão poderiam ser usadas como um adjunto ao escore de Loes, auxiliando no monitoramento da doença e alertando uma possível progressão do escore de Loes na faixa de interesse para decisões terapêuticas. .

Objective: The present study was aimed at evaluating the correlation between diffusion tensor imaging parameters and Loes score as well as whether those parameters could indicate early structural alterations. Materials and Methods: Diffusion tensor imaging measurements were obtained in 30 studies of 14 patients with X-linked adrenoleukodystrophy and were correlated with Loes scores. A control group including 28 male patients was created to establish agematched diffusion tensor imaging measurements. Inter- and intraobserver statistical analyses were undertaken. Results: Diffusion tensor imaging measurements presented strong Pearson correlation coefficients (r) of –0.86, 0.89, 0.89 and 0.84 for fractional anisotropy and mean, radial and axial diffusivities (p < 0.01). Analysis of changes in diffusion tensor measurements at early stage of the disease indicates that mean and radial diffusivities might be useful to predict the disease progression. Conclusion: Measurements of diffusion tensor parameters can be used as an adjunct to the Loes score, aiding in the monitoring of the disease and alerting for possible Loes score progression in the range of interest for therapeutic decisions. .

Isolated Cerebellar Variant of Adrenoleukodystrophy with a de novo Adenosine Triphosphate-Binding Cassette D1 (ABCD1) Gene Mutation

X-linked adrenoleukodystrophy (X-ALD) shows a wide range of phenotypic expression, but clinical presentation as an isolated lesion of the cerebellar white matter and dentate nuclei has not been reported. We report an unusual presentation of X-ALD only with an isolated lesion of the cerebellar white matter and dentate nuclei. The proband, a 37-year-old man presented with bladder incontinence, slurred speech, dysmetria in all limbs, difficulties in balancing, and gait ataxia. Brain magnetic resonance imaging showed an isolated signal change of white matter around the dentate nucleus in cerebellum. With high level of very long chain fatty acid, gene study showed a de novo mutation in exon 1 at nucleotide position c.277_296dup20 (p.Ala100Cysfs*10) of the adenosine triphosphate-binding cassette D1 gene. It is advised to consider X-ALD as a differential diagnosis in patients with isolated cerebellar degeneration symptoms.

The Genetically Modified Polysialylated Form of Neural Cell Adhesion Molecule-Positive Cells for Potential Treatment of X-Linked Adrenoleukodystrophy

PURPOSE: Cell transplantation of myelin-producing exogenous cells is being extensively explored as a means of remyelinating axons in X-linked adrenoleukodystrophy. We determined whether 3,3',5-Triiodo-L-thyronine (T3) overexpresses the ABCD2 gene in the polysialylated (PSA) form of neural cell adhesion molecule (NCAM)-positive cells and promotes cell proliferation and favors oligodendrocyte lineage differentiation. MATERIALS AND METHODS: PSA-NCAM+ cells from newborn Sprague-Dawley rats were grown for five days on uncoated dishes in defined medium with or without supplementation of basic fibroblast growth factor (bFGF) and/or T3. Then, PSA-NCAM+ spheres were prepared in single cells and transferred to polyornithine/fibronectin-coated glass coverslips for five days to determine the fate of the cells according to the supplementation of these molecules. T3 responsiveness of ABCD2 was analyzed using real-time quantitative polymerase chain reaction, the growth and fate of cells were determined using 5-bromo-2-deoxyuridine incorporation and immunocytochemistry, respectively. RESULTS: Results demonstrated that T3 induces overexpression of the ABCD2 gene in PSA-NCAM+ cells, and can enhance PSA-NCAM+ cell growth in the presence of bFGF, favoring an oligodendrocyte fate. CONCLUSION: These results may provide new insights into investigation of PSA-NCAM+ cells for therapeutic application to X-linked adrenoleukodystrophy.

A new method avoids interference of ABCD1 pseudogenes in molecular diagnosis of X-linked adrenoleukodystrophy / 第二军医大学学报

Objective: To introduce a new method which can avoid the interference of ABCD1 pseudogenes in the molecular diagnosis of X-linked adrenoleukodystrophy. Methods: The coding regions of ABCD1 gene of 3 unrelated Chinese patients with X-linked adrenoleukodystrophy were amplified from the total RNA of peripheral blood by long distance RT-PCR; the product was further amplified in 4 segments in a second round PCR; and the PCR products were purified and directly sequenced. To confirm the mutations, the genomic DNA from peripheral blood cells of the patients was analyzed by direct sequencing after amplification of the ABCD1 genes by nested PCR, in which the product of the first round PCR covered the fragment starting from exon 6 and ending at 3′UTR of the ABCD1 gene. Results: The 3 Chinese patients with X-linked adrenoleukodystrophy had 3 different base substitutions(2235C>T,2065C>T and 2190A>T)in the ABCD1 genes of the 3 probands and their mothers, which resulted in 2 missense mutations (R617C and P560L) and one nonsense mutation (K602X). Conclusion: Nested PCR can rapidly and efficiently avoid the interference of ABCD1 pseudogenes in the molecular diagnosis of X-ALD.

Lorenzo's Oil Treatment in X-linked Adrenoleukodystrophy / 소아과

PURPOSE: Though more than 15 years have passed after introduction of Lorenzo's oil therapy in X- linked adrenoleukodystrophy (ALD), its efficacy is still fully not known. In patients who already have neurologic symptoms, most reports indicate that the neurologic disability continues to increase. We evaluated its efficacy in X-linked ALD patients. METHODS: Four patients who were treated with Lorenzo's oil for at least 12 months were enrolled from 1996 to 2003. During treatment, changes of neurologic symptoms, brain magnetic resonance imaging (MRI) findings, and serum saturated very long-chain fatty acid (C26: 0) were assessed. RESULTS: Two patients with childhood cerebral ALD had progression of neurologic symptoms and MRI lesions during treatment. One asymptomatic patient developed childhood cerebral ALD after six year treatment of Lorenzo's oil. One "Addison only" patient remained neurologically intact after three years. During Lorenzo's oil therapy, serum C26: 0 levels which had increased at diagnosis decreased in all four patients. CONCLUSION: Treatment with Lorenzo's oil did not prevent disease progression in childhood cerebral ALD patients who were already symptomatic. Long term follow up will be needed in asymptomatic ALD including "Addison only" to reveal the efficacy of Lorenzo's oil.

Analysis of ABCD1 Gene Mutation in Patients with X-Linked Adrenoleukodystrophy / 实用儿科临床杂志

Objective To analyze the ABCD1 gene mutations in 5 cases of X-linked adrenoleukodystrophy(X-ALD) patients and 2 cases of their mothers.Methods Of 5 patients with X-ALD,10 exons and flanking intronic sequences of ABCD1 gene were amplified by polyme-rase chain reaction,and then sequenced directly.The outcomes were compared with normal ABCD1 sequencings to identify the mutation type and site.Thirty normal men were examined in the mean time as control for the confirmation of mutations and gene polymorphisms.Results Three patients showed ABCD1 gene mutations,1 had a point mutation in exon 6,Arg518Gly(CGG→GGG);2 patients showed the same novel mutation in exon 1 with 8 bases deletion(134del8).Four gene polymorphisms were identified in exon 7.They were Gly551X(GGC→GGT),Arg554His(CGT→CAT),Gln567Arg(CAA→CGA) and Val582Ile(GTC→ATC).ABCD1 gene mutation was not found in 2 mothers from 2 unrelated fa-milies with X-ALD.Conclusions Three cases of 5 were detected for ABCD1 gene mutations.Between them,the 134del8 mutation is a novel one.Four new gene polymorphisms were detected in exon 7 in normal Chinese people,which were Gly551X,Arg554His,Gln567Arg and Val582Ile.