Kinky hair disease: twenty five years later

Focus on cuproptosis: Exploring new mechanisms and therapeutic application prospects of cuproptosis regulation

Cuproptosis is a novel form of regulated cell death, which plays an important role in the physiological and pathological processes of the human body. Despite the increasing research on cuproptosis-related genes (CRGs) and their correlation with diseases, the pathogenesis of cuproptosis-related diseases remains unclear. Furthermore, there is a lack of reviews on the emerging technologies for regulating cuproptosis in disease treatment. This study delves into the copper-induced cell death mechanism, distinguishing cuproptosis from mechanisms like oxidative stress, glutathione synthesis inhibition, and ubiquitin-proteasome system inhibition. Several long-standing mysteries of diseases such as Wilson's disease and Menkes disease may be attributed to the occurrence of cuproptosis. In addition, we also review the detection indicators related to cuproptosis, providing targets for the diagnosis of cuproptosis-related diseases, and summarize the application value of cuproptosis in tumor therapy to better elucidate the impact of copper in cell death and diseases, and thus to promote the application prospects and possible strategies of cuproptosis-related substances, such as copper ion chelators, copper ion carriers, and copper nanomaterials, in disease therapy.

The physiological and pathophysiological roles of copper in the nervous system

Copper is a critical trace element in biological systems due the vast number of essential enzymes that require the metal as a cofactor, including cytochrome c oxidase, superoxide dismutase and dopamine-β-hydroxylase. Due its key role in oxidative metabolism, antioxidant defence and neurotransmitter synthesis, copper is particularly important for neuronal development and proper neuronal function. Moreover, increasing evidence suggests that copper also serves important functions in synaptic and network activity, the regulation of circadian rhythms, and arousal. However, it is important to note that because of copper's ability to redox cycle and generate reactive species, cellular levels of the metal must be tightly regulated to meet cellular needs while avoiding copper-induced oxidative stress. Therefore, it is essential that the intricate system of copper transporters, exporters, copper chaperones and copper trafficking proteins function properly and in coordinate fashion. Indeed, disorders of copper metabolism such as Menkes disease and Wilson disease, as well as diseases linked to dysfunction of copper-requiring enzymes, such as SOD1-linked amyotrophic lateral sclerosis, demonstrate the dramatic neurological consequences of altered copper homeostasis. In this review, we explore the physiological importance of copper in the nervous system as well as pathologies related to improper copper handling.

Cuproptosis: Unraveling the Mechanisms of Copper-Induced Cell Death and Its Implication in Cancer Therapy

Copper, an essential element for various biological processes, demands precise regulation to avert detrimental health effects and potential cell toxicity. This paper explores the mechanisms of copper-induced cell death, known as cuproptosis, and its potential health and disease implications, including cancer therapy. Copper ionophores, such as elesclomol and disulfiram, increase intracellular copper levels. This elevation triggers oxidative stress and subsequent cell death, offering potential implications in cancer therapy. Additionally, copper ionophores disrupt mitochondrial respiration and protein lipoylation, further contributing to copper toxicity and cell death. Potential targets and biomarkers are identified, as copper can be targeted to those proteins to trigger cuproptosis. The role of copper in different cancers is discussed to understand targeted cancer therapies using copper nanomaterials, copper ionophores, and copper chelators. Furthermore, the role of copper is explored through diseases such as Wilson and Menkes disease to understand the physiological mechanisms of copper. Exploring cuproptosis presents an opportunity to improve treatments for copper-related disorders and various cancers, with the potential to bring significant advancements to modern medicine.

The Role of Copper Homeostasis in Brain Disease

In the human body, copper is an important trace element and is a cofactor for several important enzymes involved in energy production, iron metabolism, neuropeptide activation, connective tissue synthesis, and neurotransmitter synthesis. Copper is also necessary for cellular processes, such as the regulation of intracellular signal transduction, catecholamine balance, myelination of neurons, and efficient synaptic transmission in the central nervous system. Copper is naturally present in some foods and is available as a dietary supplement. Only small amounts of copper are typically stored in the body and a large amount of copper is excreted through bile and urine. Given the critical role of copper in a breadth of cellular processes, local concentrations of copper and the cellular distribution of copper transporter proteins in the brain are important to maintain the steady state of the internal environment. The dysfunction of copper metabolism or regulatory pathways results in an imbalance in copper homeostasis in the brain, which can lead to a myriad of acute and chronic pathological effects on neurological function. It suggests a unique mechanism linking copper homeostasis and neuronal activation within the central nervous system. This article explores the relationship between impaired copper homeostasis and neuropathophysiological progress in brain diseases.

Golgi-Dependent Copper Homeostasis Sustains Synaptic Development and Mitochondrial Content

Rare genetic diseases preponderantly affect the nervous system causing neurodegeneration to neurodevelopmental disorders. This is the case for both Menkes and Wilson disease, arising from mutations in ATP7A and ATP7B, respectively. The ATP7A and ATP7B proteins localize to the Golgi and regulate copper homeostasis. We demonstrate genetic and biochemical interactions between ATP7 paralogs with the conserved oligomeric Golgi (COG) complex, a Golgi apparatus vesicular tether. Disruption of Drosophila copper homeostasis by ATP7 tissue-specific transgenic expression caused alterations in epidermis, aminergic, sensory, and motor neurons. Prominent among neuronal phenotypes was a decreased mitochondrial content at synapses, a phenotype that paralleled with alterations of synaptic morphology, transmission, and plasticity. These neuronal and synaptic phenotypes caused by transgenic expression of ATP7 were rescued by downregulation of COG complex subunits. We conclude that the integrity of Golgi-dependent copper homeostasis mechanisms, requiring ATP7 and COG, are necessary to maintain mitochondria functional integrity and localization to synapses.SIGNIFICANCE STATEMENT Menkes and Wilson disease affect copper homeostasis and characteristically afflict the nervous system. However, their molecular neuropathology mechanisms remain mostly unexplored. We demonstrate that copper homeostasis in neurons is maintained by two factors that localize to the Golgi apparatus, ATP7 and the conserved oligomeric Golgi (COG) complex. Disruption of these mechanisms affect mitochondrial function and localization to synapses as well as neurotransmission and synaptic plasticity. These findings suggest communication between the Golgi apparatus and mitochondria through homeostatically controlled cellular copper levels and copper-dependent enzymatic activities in both organelles.

Rare Genetic Diseases: Nature's Experiments on Human Development

Rare genetic diseases are the result of a continuous forward genetic screen that nature is conducting on humans. Here, we present epistemological and systems biology arguments highlighting the importance of studying these rare genetic diseases. We contend that the expanding catalog of mutations in ∼4,000 genes, which cause ∼6,500 diseases and their annotated phenotypes, offer a wide landscape for discovering fundamental mechanisms required for human development and involved in common diseases. Rare afflictions disproportionately affect the nervous system in children, but paradoxically, the majority of these disease-causing genes are evolutionarily ancient and ubiquitously expressed in human tissues. We propose that the biased prevalence of childhood rare diseases affecting nervous tissue results from the topological complexity of the protein interaction networks formed by ubiquitous and ancient proteins encoded by childhood disease genes. Finally, we illustrate these principles discussing Menkes disease, an example of the discovery power afforded by rare diseases.

The Endolysosomal System and Proteostasis: From Development to Degeneration

How do neurons adapt their endolysosomal system to address the particular challenge of membrane transport across their elaborate cellular landscape and to maintain proteostasis for the lifetime of the organism? Here we review recent findings that address this central question. We discuss the cellular and molecular mechanisms of endolysosomal trafficking and the autophagy pathway in neurons, as well as their role in neuronal development and degeneration. These studies highlight the importance of understanding the basic cell biology of endolysosomal trafficking and autophagy and their roles in the maintenance of proteostasis within the context of neurons, which will be critical for developing effective therapies for various neurodevelopmental and neurodegenerative disorders.

The mouse curly whiskers (cw) mutations are recessive alleles of hephaestin-like 1 (Hephl1)

The spontaneous, curly whiskers mutation (abbreviated cw) generates kinky, brittle vibrissae in homozygous mice. Although cw has been mapped to the centromeric end of mouse Chromosome 9, no particular gene has been causally implicated, and this lack of genetic assignment has stymied cw's complete molecular and functional analysis. As a foundation for its positional cloning, we have fine-mapped cw to a small, 0.57 Mb interval that contains only three skin-expressed genes, including hephaestin-like 1 (Hephl1), which encodes a membrane-bound, multi-copper ferroxidase. Sequence analysis of all Hephl1 coding regions in cw/cw mutants revealed a single-base-pair substitution that alters Hephl1 mRNA splicing, and is specific to the cw allele, only. Sequence analysis of a second, independent, re-mutation to curly whiskers (that we verified by complementation testing with cw and have designated cw^2J) revealed a distinct defect in Hephl1 (a frame-shifting, single-base-pair insertion) that is specific to cw^2J. The results presented strongly suggest that defects in the Hephl1 gene are the molecular basis of the classical, curly-whiskers mutant phenotypes.

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Genetic mapping identifies a small number of candidates for the mouse cw mutation.

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Sequence analysis of one of these candidates, Hephl1, reveals a cw-specific defect.

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Analysis of skin mRNA indicates that the Hephl1^cw transcript is aberrantly spliced.

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Complementation testing identifies a distinct re-mutation to curly whiskers, cw^2J.

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Sequence analysis of Hephl1 reveals a cw^2J-specific, frameshifting insertion.

Online immunocapture ICP-MS for the determination of the metalloprotein ceruloplasmin in human serum

Objective

The human copper-protein ceruloplasmin (Cp) is the major copper-containing protein in the human body. The accurate determination of Cp is mandatory for the reliable diagnosis of several diseases. However, the analysis of Cp has proven to be difficult. The aim of our work was a proof of concept for the determination of a metalloprotein-based on online immunocapture ICP-MS. The immuno-affinity step is responsible for the enrichment and isolation of the analyte from serum, whereas the compound-independent quantitation with ICP-MS delivers the sensitivity, precision, and large dynamic range. Off-line ELISA (enzyme-linked immunosorbent assay) was used in parallel to confirm the elution profile of the analyte with a structure-selective method. The total protein elution was observed with the ³²S mass trace. The ICP-MS signals were normalized on a ⁵⁹Co signal.

Results

The human copper-protein Cp could be selectively determined. This was shown with pure Cp and with a sample of human serum. The good correlation with off-line ELISA shows that Cp could be captured and eluted selectively from the anti-Cp affinity column and subsequently determined by the copper signal of ICP-MS.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3324-7) contains supplementary material, which is available to authorized users.

Role of the ECM in notochord formation, function and disease

The notochord is a midline structure common to all chordate animals; it provides mechanical and signaling cues for the developing embryo. In vertebrates, the notochord plays key functions during embryogenesis, being a source of developmental signals that pattern the surrounding tissues. It is composed of a core of vacuolated cells surrounded by an epithelial-like sheath of cells that secrete a thick peri-notochordal basement membrane made of different extracellular matrix (ECM) proteins. The correct deposition and organization of the ECM is essential for proper notochord morphogenesis and function. Work carried out in the past two decades has allowed researchers to dissect the contribution of different ECM components to this embryonic tissue. Here, we will provide an overview of these genetic and mechanistic studies. In particular, we highlight the specific functions of distinct matrix molecules in regulating notochord development and notochord-derived signals. Moreover, we also discuss the involvement of ECM synthesis and its remodeling in the pathogenesis of chordoma, a malignant bone cancer that originates from remnants of notochord remaining after embryogenesis.

Menkes disease: what a multidisciplinary approach can do

Disorders of copper homeostasis are currently recognized across the life span. Their recognition and links to human disease have spanned several decades, beginning with the recognition of a degenerative disorder in the offspring of sheep grazing in copper-deficient pastures, through to the description of infants suffering from a progressive neurodegenerative disorder characterized by epileptic seizures, developmental regression, failure to thrive, and an unusual hair quality (giving the condition its distinctive label of “kinky hair disease”). In this review, we trace the historical background and describe the biochemistry and physiology of copper metabolism and transport, inheritance patterns, molecular genetics, and genotype–phenotype correlations based on current understanding of the disorder. It is clear from the clinical presentations and variants that disorders of copper homeostasis include phenotypes ranging from mild occipital horn syndrome to intermediate and severe forms of classical Menkes disease. The symptoms involve multiple organ systems such as brain, lung, gastrointestinal tract, urinary tract, connective tissue, and skin. A multisystem disorder needs a multidisciplinary approach to care, as treatment interventions permit longer survival for some individuals. Animal models have been developed to help screen treatment options and provide a better understanding of these disorders in the laboratory. Finally, we propose a multidisciplinary approach to promote continued research (both basic and clinical) to improve survival, quality of life, and care for these conditions.

The notochord: structure and functions

The notochord is an embryonic midline structure common to all members of the phylum Chordata, providing both mechanical and signaling cues to the developing embryo. In vertebrates, the notochord arises from the dorsal organizer and it is critical for proper vertebrate development. This evolutionary conserved structure located at the developing midline defines the primitive axis of embryos and represents the structural element essential for locomotion. Besides its primary structural function, the notochord is also a source of developmental signals that patterns surrounding tissues. Among the signals secreted by the notochord, Hedgehog proteins play key roles during embryogenesis. The Hedgehog signaling pathway is a central regulator of embryonic development, controlling the patterning and proliferation of a wide variety of organs. In this review, we summarize the current knowledge on notochord structure and functions, with a particular emphasis on the key developmental events that take place in vertebrates. Moreover, we discuss some genetic studies highlighting the phenotypic consequences of impaired notochord development, which enabled to understand the molecular basis of different human congenital defects and diseases.

Role of micronutrients in skin health and function

Skin is the first line of defense for protecting our bodies against external perturbations, including ultraviolet (UV) irradiation, mechanical/chemical stress, and bacterial infection. Nutrition is one of many factors required for the maintenance of overall skin health. An impaired nutritional status alters the structural integrity and biological function of skin, resulting in an abnormal skin barrier. In particular, the importance of micronutrients (such as certain vitamins and minerals) for skin health has been highlighted in cell culture, animal, and clinical studies. These micronutrients are employed not only as active compounds in therapeutic agents for treating certain skin diseases, but also as ingredients in cosmetic products. Here, the author describes the barrier function of the skin and the general nutritional requirements for skin health. The goal of this review is to discuss the potential roles and current knowledge of selected micronutrients in skin health and function.

Molecular basis of neurodegeneration and neurodevelopmental defects in Menkes disease

ATP7A mutations impair copper metabolism resulting in three distinct genetic disorders in humans. These diseases are characterized by neurological phenotypes ranging from intellectual disability to neurodegeneration. Severe ATP7A loss-of-function alleles trigger Menkes disease, a copper deficiency condition where systemic and neurodegenerative phenotypes dominate clinical outcomes. The pathogenesis of these manifestations has been attributed to the hypoactivity of a limited number of copper-dependent enzymes, a hypothesis that we refer as the oligoenzymatic pathogenic hypothesis. This hypothesis, which has dominated the field for 25 years, only explains some systemic Menkes phenotypes. However, we argue that this hypothesis does not fully account for the Menkes neurodegeneration or neurodevelopmental phenotypes. Here, we propose revisions of the oligoenzymatic hypothesis that could illuminate the pathogenesis of Menkes neurodegeneration and neurodevelopmental defects through unsuspected overlap with other neurological conditions including Parkinson's, intellectual disability, and schizophrenia.

Epilepsy in children with Menkes disease: a systematic review of literature

Menkes disease is a lethal multisystemic disorder of copper metabolism characterized by connective tissue abnormalities, progressive neurodegeneration and peculiar "kinky hair." Epilepsy is one of the main clinical features of this disease but it has been described in detail by only a few authors. Most patients develop seizures from 2 to 3 months of age, accompanied by a neurodevelopmental regression. The history of epilepsy is usually characterized by 3 stages: an early stage with focal clonic seizures and status epilepticus, an intermediate stage with infantile spasms, and a late stage with multifocal, myoclonic, and tonic seizures. At the onset, epilepsy can be controlled with anticonvulsant therapy, whereas with the progression of disease, it becomes extremely resistant to all antiepileptic drugs. In this article, we analyze clinical and electroencephalographic (EEG) characteristics of epilepsy in patients with this syndrome.

Neonatal erythroderma as a first manifestation of Menkes disease

Menkes disease is an X-linked recessive lethal multisystemic disorder of copper metabolism. Progressive neurodegeneration, connective tissue disturbances, and peculiar kinky hair are the main manifestations. The low serum copper and ceruloplasmin suggests the diagnosis, which is confirmed by mutation analysis of the ATP7A gene. We report an exceptional presentation of classic Menkes disease with neonatal erythroderma. Genetic study revealed a deletion in exons 8 to 12 in the ATP7A gene. This study could allow pediatricians and pediatric dermatologists to diagnose the disorder as early as possible to establish prompt treatment with parenteral copper-histidine supplementation to improve prognosis.

Cervical and intracranial arterial anomalies in 70 patients with PHACE syndrome

BACKGROUND AND PURPOSE

Cerebral and cervical arterial abnormalities are the most common non-cutaneous anomaly in PHACE syndrome, but the location and type of arterial lesions that occur have not been systematically assessed in a large cohort. Our aim was to characterize the phenotypic spectrum of arteriopathy, assess the frequency with which different arteries are involved, and evaluate spatial relationships between arteriopathy, brain structural lesions, and hemangiomas in PHACE syndrome.

MATERIALS AND METHODS

Intracranial MRA and/or CTA images from 70 children and accompanying brain MR images in 59 patients with arteriopathy and PHACE syndrome were reviewed to identify the type and location of arterial lesions and brain abnormalities. Five categories of arteriopathy were identified and used for classification: dysgenesis, narrowing, nonvisualization, primitive embryonic carotid-vertebrobasilar connections, and anomalous arterial course or origin. Univariate logistic regression analyses were performed to test for associations between arteriopathy location, hemangiomas, and brain abnormalities.

RESULTS

By study design, all patients had arterial abnormalities, and 57% had >1 form of arteriopathy. Dysgenesis was the most common abnormality (56%), followed by anomalous course and/or origin (47%), narrowing (39%), and nonvisualization (20%). Primitive embryonic carotid-vertebrobasilar connections were present in 20% of children. Hemangiomas were ipsilateral to arteriopathy in all but 1 case. The frontotemporal and/or mandibular facial segments were involved in 97% of cases, but no other specific associations between arteriopathy location and hemangioma sites were detected. All cases with posterior fossa anomalies had either ICA anomalies or persistent embryonic carotid-basilar connections.

CONCLUSIONS

The arteriopathy of PHACE syndrome commonly involves the ICA and its embryonic branches, ipsilateral to the cutaneous hemangioma, with dysgenesis and abnormal arterial course the most commonly noted abnormalities. Brain abnormalities are also typically ipsilateral.

Serum ceruloplasmin and copper are early biomarkers for traumatic brain injury-associated elevated intracranial pressure

High intracranial pressure (ICP) is a prominent secondary pathology after traumatic brain injury (TBI) and is a major contributor to morbidity and mortality. Currently, there are no clinically proven methods for predicting which TBI patients will develop high ICP. In the present study, we examined whether the serum levels of the copper-binding protein ceruloplasmin are differentially altered in patients with elevated ICP (> or =25 mmHg) vs. those whose ICP remained below 20 mmHg throughout the study period. Consistent with its role as an acute-phase reactant, we found that ceruloplasmin levels were significantly increased by 3 days post-TBI compared with healthy volunteers. However, prior to this delayed increase, ceruloplasmin levels during the first 24 hr following injury were found to be significantly reduced in patients who subsequently developed high ICP. This decrease was found to have prognostic accuracy in delineating TBI patients based on their ICP status (cutoff of 140 microg/ml; sensitivity: 87%, specificity: 73%), Likewise, low total serum copper (below 1.32 microg/ml) was also found to be predictive of high ICP (sensitivity 86%, specificity 73%). These results suggest that initial serum ceruloplasmin/copper levels may have diagnostic value in predicting patients at risk for developing high intracranial pressure.

Copper deficiency myelopathy

Acquired copper deficiency has been recognised as a rare cause of anaemia and neutropenia for over half a century. Copper deficiency myelopathy (CDM) was only described within the last decade, and represents a treatable cause of non-compressive myelopathy which closely mimics subacute combined degeneration due to vitamin B12 deficiency. Here, 55 case reports from the literature are reviewed regarding their demographics, aetiology, haematological and biochemical parameters, spinal imaging, treatment and outcome. The pathophysiology of disorders of copper metabolism is discussed. CDM most frequently presented in the fifth and sixth decades and was more common in women (F:M = 3.6:1). Risk factors included previous upper gastrointestinal surgery, zinc overload and malabsorption syndromes, all of which impair copper absorption in the upper gastrointestinal tract. No aetiology was established in 20% of cases. High zinc levels were detected in some cases not considered to have primary zinc overload, and in this situation the contribution of zinc to the copper deficiency state remained unclear. Cytopenias were found in 78%, particularly anaemia, and a myelodysplastic syndrome may have been falsely diagnosed in the past. Spinal MRI was abnormal in 47% and usually showed high T2 signal in the posterior cervical and thoracic cord. In a clinically compatible case, CDM may be suggested by the presence of one or more risk factors and/or cytopenias. Low serum copper and caeruloplasmin levels confirmed the diagnosis and, in contrast to Wilson's disease, urinary copper levels were typically low. Treatment comprised copper supplementation and modification of any risk factors, and led to haematological normalisation and neurological improvement or stabilisation. Since any neurological recovery was partial and case numbers of CDM will continue to rise with the growing use of bariatric gastrointestinal surgery, clinical vigilance will remain the key to minimising neurological sequelae. Recommendations for treatment and prevention are made.

Zebrafish mutants calamity and catastrophe define critical pathways of gene-nutrient interactions in developmental copper metabolism

Nutrient availability is an important environmental variable during development that has significant effects on the metabolism, health, and viability of an organism. To understand these interactions for the nutrient copper, we used a chemical genetic screen for zebrafish mutants sensitive to developmental copper deficiency. In this screen, we isolated two mutants that define subtleties of copper metabolism. The first contains a viable hypomorphic allele of atp7a and results in a loss of pigmentation when exposed to mild nutritional copper deficiency. This mutant displays incompletely penetrant skeletal defects affected by developmental copper availability. The second carries an inactivating mutation in the vacuolar ATPase that causes punctate melanocytes and embryonic lethality. This mutant, catastrophe, is sensitive to copper deprivation revealing overlap between ion metabolic pathways. Together, the two mutants illustrate the utility of chemical genetic screens in zebrafish to elucidate the interaction of nutrient availability and genetic polymorphisms in cellular metabolism.

Copper is an essential nutrient required for multiple biologic functions. Proper uptake, transport, and excretion of copper are critical for use of this metal while reducing its inherent toxicity. While several key proteins involved in this process have been identified, there are still gaps in our understanding of copper metabolism—particularly during early development. We have used zebrafish, a genetically useful animal model system, to study genetic interactions with copper deficiency during development. We treated mutant embryonic zebrafish with a chelator that reduces the level of available copper and screened for mutants that displayed a copper deficient phenotype only in the presence of the chelator. We identified and characterized two mutants that advance our understanding of copper metabolism during the early periods of development, as well as show an interaction between copper metabolism and another fundamental pathway—that of proton transport. Our results expand our knowledge of copper metabolism and illustrate the power of this type of genetic screen in zebrafish to elucidate mechanisms of nutrient metabolism.

Patterns of correlation of plasma ceruloplasmin in sepsis

BACKGROUND

In sepsis, plasma ceruloplasmin (Cp, mg/L) is known to increase as part of the acute phase response. However, there is poor knowledge of the patterns of increase and correlation with changes in other biochemical variables, and our study has been performed to investigate this aspect.

MATERIALS AND METHODS

A total of 213 simultaneous measurements of Cp and other acute phase proteins, biochemical variables, and amino acids were performed on nine patients with severe sepsis, and processed by regression analysis.

RESULTS

Mean Cp was 478 +/- 119 mg/L (median 488, range 242-784). Significant direct correlations between Cp and C-reactive protein, alpha-1-antitrypsin and alpha-2-macroglobulin (P < 0.001 for all) were all simultaneously influenced by the level of alkaline phosphatase, which was an independent determinant of increased Cp (P < 0.001). Cp increased further with decreasing plasma pH and increasing triglyceride, taurine levels, and distance from the onset of sepsis (P < 0.001 for all). The maximum increases in Cp were associated with the presence of cholestasis, increasing triglyceride levels, and metabolic acidosis. With regard to septic liver dysfunction, while signs of cholestasis were mostly reflected in greater increases in Cp, increasing bilirubin in the presence of normal alkaline phosphatase was mostly correlated with abnormal increases in cyst(e)ine, cystathionine, and tyrosine levels.

CONCLUSIONS

These data characterize the patterns of correlation of Cp within the biochemical abnormalities of sepsis, and may provide new insights into the pathophysiology of septic hepatobiliary dysfunction.

Menkes syndrome presenting as myoclonic seizures: neuroimaging and EEG observations

The authors report an 11-month-old boy with Menkes kinky hair disease who presented with global delay in acquiring milestones and repeated myoclonic jerks. He had scanty, hypopigmented scalp hairs with steely wool-like texture and intervening zones of alopecia. There was low serum ceruloplasmin (5 mg/dL) and copper (24.2 microg/dL). Neuroimaging of the brain revealed marked cerebral atrophy and significant delayed myelination. Magnetic resonance angiography showed tortuous cerebral and neck blood vessels. There was poor therapeutic response to symptomatic treatment.

Epilepsy in Menkes Disease: Analysis of Clinical Stages

PURPOSE

Epilepsy is one of the main features of Menkes disease (MD), although it is not described in depth. To determine the spectrum of epilepsy, we studied its main characteristics.

METHODS

Based on clinical charts, we retrospectively analyzed the evolution of electroclinical features of 12 patients with confirmed MD.

RESULTS

Epilepsy could be divided into three periods: (a) an early stage (median age, 3 months), characterized by focal clonic status epilepticus, usually triggered by fever (10 patients). Ictal EEG showed runs of slow spike-waves and slow waves in the posterior regions, and interictal EEG multifocal and polymorphic slow waves (three cases), or mixed slow spike-waves and slow waves (seven cases). Partial seizure control was obtained in nine patients during 5.9 months; (b) an intermediate stage (median age, 10 months) with intractable infantile spasms (11 patients) in which interictal EEG demonstrated modified hypsarrhythmia (seven cases), diffuse irregular slow waves and spike-waves (four cases). Six patients died at the median age of 15 months; and (c) a late stage in the six remaining patients (median age, 25 months), with multifocal seizures, tonic spasms, and myoclonus in four patients, whereas two patients became seizure free. Interictal EEG showed multifocal high-amplitude activity, mixed with irregular slow waves in all six cases. These patients died at the median age of 3.6 years.

CONCLUSIONS

Based on a relatively large series of MD patients with a quite prolonged survival, we individualized three successive periods in the course of epilepsy: early focal status, then infantile spasms, and then myoclonic and multifocal epilepsy after age 2 years.

Is there a role for copper in neurodegenerative diseases?

Copper is an essential metal in living organisms; thus, the maintenance of adequate copper levels is of vital importance and is highly regulated. Dysfunction of copper metabolism leading to its excess or deficiency results in severe ailments. Two examples of illnesses related to alterations in copper metabolism are Menkes and Wilson diseases. Several proteins are involved in the maintenance of copper homeostasis, including copper transporters and metal chaperones. In the last several years, the beta-amyloid-precursor protein (beta-APP) and the prion protein (PrP(C)), which are related to the neurodegenerative disorders Alzheimer and prion diseases respectively, have been associated with copper metabolism. Both proteins bind copper through copper-binding domains that also have been shown to reduce copper in vitro. Moreover, this ability to reduce copper is associated with a neuroprotective effect exerted by the copper-binding domain of both proteins against copper in vivo. In addition to a functional link between copper and beta-APP or PrP(C), evidence suggests that copper has a role in Alzheimer and prion diseases. Here, we review the evidence that supports both, the role of beta-APP and PrP(C), in copper metabolism and the putative role of copper in neurodegenerative diseases.

The effects of copper-histidine therapy on brain metabolism in a patient with Menkes disease: a proton magnetic resonance spectroscopic study

We report on metabolic changes in the brain of a boy with Menkes disease. He was treated with parenteral copper (Cu)-histidine supplementation, from 5 months of age, and assessed with proton magnetic resonance spectroscopy ((1)H-MRS). The single-voxel (1)H-MRS before treatment revealed an accumulation of lactate and a reduced N-acetyl aspartate (NAA)/total creatine (tCr) ratio with a z-score of -3.0. During treatment, the lactate signal faded away, whereas the NAA signal gradually increased to a z-score of -1.5 at 120 days of treatment. The choline/tCr ratio did not deviate much initially (z-score +0.5), but the ratio increased markedly during treatment (z-score +4.8). Consequently, the Cu-histidine therapy initiated after the critical period still improved the neuronal metabolism, suggesting that some Cu was delivered to neurons. Nevertheless, the brain atrophy, impaired myelination, and severe neurological symptoms were not ameliorated.

Differential diagnosis of hair loss in children. Differentialdiagnose des Haarausfalls bei Kindern

Hair loss in childhood covers a broad differential diagnosis and often presents the involved dermatologist and pediatrician with a diagnostic and therapeutic challenge. Correct classification of the hair disease, especially in the case of underlying genetic syndromes, metabolic defects or endocrine disorders, is often an important prerequisite for continued normal physical and mental development of the young patients. Dealing with hair loss in childhood, one should differentiate between congenital and acquired diseases. The clinical manifestation profile, the age of the patient when the initial manifestation occurred, and the presence of associated symptoms are important for the classification of the hair disease. In the present paper, a classification of hair loss in childhood based on clinical appearance, age of onset and associated symptoms is proposed as a guide for the evaluation of hair loss and alopecia in childhood.

A human prion protein peptide (PrP(59-91)) protects against copper neurotoxicity

Human cellular prion protein (PrP(C)) is involved in several neurodegenerative disorders; however, its normal function is unknown. We report here that a synthetic peptide corresponding to the four-octarepeat sequence of the PrP(C) (PrP(59-91)) protects hippocampal neurons against copper neurotoxic effects in vivo. Using a rat bilateral intrahippocampal injection model, we found that PrP(59-91) protects against copper-induced neurotoxicity, including a recovery in spatial learning performance and a reduced neuronal cell loss and astrogliosis. Previous studies from our laboratory indicated that a tryptophan (Trp) residue plays a key role in the reduction of copper(II) to copper(I); therefore several PrP(59-91) fragments lacking histidine (His) and Trp residues were tested for their capacity to protect from copper toxicity. A PrP(59-91) peptide lacking His residue shows as much neuroprotection as the native peptide; however, PrP(59-91) without Trp residues only partially protected against copper toxicity. The neuroprotective effect not only occurs with PrP(59-91), in fact a full neuroprotection was also observed using just one octamer of the N-terminal region of prion protein. We conclude that the N-terminal tandem octarepeat of the human PrP(C) protects neurons against copper toxicity by a differential contribution of the binding (His) and reducing (Trp) copper activities of PrP(59-91). Our results are consistent with the idea that PrP(C) function is related to copper homeostasis.

Copper deficiency induces the upregulation of the copper chaperone for Cu/Zn superoxide dismutase in weanling male rats

The most commonly used indices for determining copper deficiency in humans are reduced serum/plasma copper concentration and decreased activity of ceruloplasmin and Cu/Zn superoxide dismutase (SOD1). However, these indicators are influenced by many factors unrelated to copper status and lack the sensitivity required to detect marginal deficiency, limiting their usefulness in many situations. In vivo, the insertion of copper into SOD1 is dependent on the copper chaperone for SOD1 (CCS). In this study, we explored the possibility that the expression level of CCS may reflect copper status and thus serve as a useful marker of copper nutriture. Weanling male Wistar rats were fed either a normal (5.3 mg Cu/kg diet), moderately deficient (0.84 mg Cu/kg diet) or deficient (0.34 mg Cu/kg diet) copper diet for 6 wk. Rats fed moderate and deficient diets showed differences (P < 0.05) in several hematological measurements, indicating varying degrees of copper deficiency in these groups. Copper-deficient rats had reduced (P < 0.05) liver and erythrocyte SOD1 activity and body weight. Western blot analysis revealed a dose-dependent increase (P < 0.05) in CCS expression in liver and erythrocytes of copper-deficient rats. We report CCS protein level as a novel marker for assessing copper status.

A novel frameshift mutation in exon 23 of ATP7A (MNK) results in occipital horn syndrome and not in Menkes disease

Menkes disease and occipital horn syndrome (OHS) are allelic, X-linked recessive copper-deficiency disorders resulting from mutations in ATP7A, or MNK. Classic Menkes disease has a severe phenotype, with death in early childhood, whereas OHS has a milder phenotype, with, mainly, connective-tissue abnormalities. Data suggest that steady-state localization of ATP7A to the trans-Golgi network (TGN) is necessary for proper activity of lysyl oxidase, which is the predominant cuproenzyme whose activity is deficient in OHS and which is essential for maintenance of connective-tissue integrity. Recently, it was reported that ATP7A-transcript levels as low as 2%-5% of normal are sufficient to result in the milder phenotype, OHS, rather than the phenotype of Menkes disease. In contrast to previously reported cases of OHS, we describe a case of OHS in which, because of a frameshift mutation, no normal ATP7A is produced. Although abundant levels of mutant transcript are present, there are substantially reduced levels of the truncated protein, which lacks the key dileucine motif L1487L1488. It has been demonstrated that the dileucine motif L1487L1488 functions as an endocytic signal for ATP7A cycling between the TGN and the plasma membrane. The present report is the first to describe an ATP7A truncation that results in OHS rather than in Menkes disease. The data from the present report support the concepts that (1) OHS results from lower levels of functional ATP7A and (2) ATP7A does not require the dileucine motif to function in copper efflux.

Copper in disorders with neurological symptoms: Alzheimer's, Menkes, and Wilson diseases

Copper is an essential element for the activity of a number of physiologically important enzymes. Enzyme-related malfunctions may contribute to severe neurological symptoms and neurological diseases: copper is a component of cytochrome c oxidase, which catalyzes the reduction of oxygen to water, the essential step in cellular respiration. Copper is a cofactor of Cu/Zn-superoxide-dismutase which plays a key role in the cellular response to oxidative stress by scavenging reactive oxygen species. Furthermore, copper is a constituent of dopamine-beta-hydroxylase, a critical enzyme in the catecholamine biosynthetic pathway. A detailed exploration of the biological importance and functional properties of proteins associated with neurological symptoms will have an important impact on understanding disease mechanisms and may accelerate development and testing of new therapeutic approaches. Copper binding proteins play important roles in the establishment and maintenance of metal-ion homeostasis, in deficiency disorders with neurological symptoms (Menkes disease, Wilson disease) and in neurodegenerative diseases (Alzheimer's disease). The Menkes and Wilson proteins have been characterized as copper transporters and the amyloid precursor protein (APP) of Alzheimer's disease has been proposed to work as a Cu(II) and/or Zn(II) transporter. Experimental, clinical and epidemiological observations in neurodegenerative disorders like Alzheimer's disease and in the genetically inherited copper-dependent disorders Menkes and Wilson disease are summarized. This could provide a rationale for a link between severely dysregulated metal-ion homeostasis and the selective neuronal pathology.

Menkes disease: case report of an uncommon presentation with white matter lesions

Menkes disease is a rare X-linked disorder related to a defect in the copper metabolism. According to the current literature, the most frequent neuroimaging findings are cortical atrophy, chronic subdural effusion or hygroma, and vascular abnormalities. White matter lesions may be present before other features of the disease and may evolve into atrophy. We hereby report a case of Menkes disease with typical history and progression, and an early phase imaging study with important white matter abnormalities, which could have lead to diagnostic difficulties.

Urologic abnormalities in Menkes' kinky hair disease: report of three cases

Menkes' kinky hair disease is a rare congenital disorder of copper metabolism with X-linked recessive inheritance. It is well known that it is frequently associated with urologic abnormalities. The authors experienced three such cases, but each of them was different. Multiple bladder diverticula, right vesico-ureteral reflux, and right hydronephrosis were noted on the first baby boy. In the second case, hematomas in the left kidney, pelvis, ureter and the adipose capsule, which were thought to be the abnormality of vessels, were noted in the neonatal period. In the third body, multiple bladder diverticular were noted at the age of 1 year. One year, 10 months later, a spontaneous rupture at the huge diverticulum occurred.

Unusual complications in siblings with marfanoid phenotype

Marfan's syndrome has diverse manifestations that overlap with those seen in other connective tissue disorders. Visceral diverticula have been described only once in four adults with marfanoid features of recessive inheritance. Two siblings of a consanguineous marriage with marfanoid features, visceral diverticula, and diaphragmatic eventration are reported.

Diagnosis of inherited metabolic disorders affecting the nervous system

Knowledge of the molecular causes for genetic diseases that affect the nervous system is rapidly expanding. Especially striking has been the finding in several autosomal dominant neurodegenerative disorders that unstable expansions of trinucleotide repeats are responsible for the genetic disorder and that the length of the repeat can be correlated with the age of onset and the severity of symptoms. Phenotypic heterogeneity in many disorders associated with enzyme deficiencies can often be linked to the amount of residual enzyme activity occurring with different gene mutations. Making a specific diagnosis of a neurological disorder associated with genetically determined metabolic defects requires access to a laboratory that can assist in arranging for appropriate testing to be carried out. In some disorders such as the aminoacidurias diagnostic metabolic studies can be performed in hospital clinical chemistry laboratories. In others, such as the lysosomal storage diseases, a laboratory that carries out special lipid analyses and white blood cell enzyme assays will be necessary. DNA mutational analyses are becoming commercially available for diagnosing many disorders such as mitochondrial diseases and those conditions associated with expanded trinucleotide repeats. It may be necessary to contact individual research laboratories when confronted with a disorder that has been newly discovered or that is very rare. A computerised directory of specialised laboratories that perform disease specific testing for genetic disorders should be useful in choosing the appropriate diagnostic or research laboratory.

Menkes disease

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Electrophysiological and 99mTc-HMPAO-SPECT studies in Menkes disease

A diagnosis of Menkes kinky hair disease was made in two brothers who had typical clinical symptoms and laboratory findings. The older one, 11 months old at the time of diagnosis, showed an EEG pattern of low amplitude and slow waves. Visual evoked potentials (VEPs) were absent, brainstem auditory evoked potentials (BAEPs) were abnormal. Regional cerebral blood flow (rCBF) studied by hexamethylpropyleneamine oxime single photon emission computed tomography (99mTc-HMPAO-SPECT) revealed reduced blood flow in both frontal and the right temporal regions. The younger boy, followed from birth, started seizures at the age of 3 months and had a hypsarrhythmia-like EEG. BAEPs were abnormal with prolongation of the latencies at the age of 12 months, while VEPs were near normal at 6 months, but disappeared by the age of 18 months. 99mTc-HMPAO-SPECT revealed an unexpected left parietal hyperperfusion.

The mottled gene is the mouse homologue of the Menkes disease gene

The mottled mouse has been proposed as an animal model for Menkes disease, an X-linked disorder of copper transport. The recent isolation of a copper-transporting ATPase gene responsible for Menkes disease has allowed us to test this hypothesis. Here we report the isolation and sequence of the mouse homologue of this gene. We show that two mottled (Mo) alleles, dappled (Modp) and blotchy (Moblo), have abnormalities in the murine mRNA and that Modp has a partial gene deletion. These studies prove that the mottled mouse is the murine model for Menkes disease, providing the basis for future biochemical and therapeutic studies.

Menkes' disease: perspective and update on a fatal copper disorder

Although the causes of the abnormal copper utilization seen in Menkes' disease remain unknown, a candidate gene reported by three laboratories has narrowed the search for the defective or missing factor. These genetic studies also suggest that a copper ATPase may be important in normal copper metabolism.

Spectrum of EEG findings in Menkes disease

We evaluated electroencephalograms (EEGs) in 10 boys with Menkes disease, ranging in age from 9 days to 27 months. Three of 10 tracings were normal (the newborn, his 27-month-old half-brother with the classic phenotype, and a 27-month-old mildly affected patient). Plasma copper levels were low in all patients except the newborn and tended to be lowest in patients whose EEGs were moderately or severely abnormal. EEG differences in Menkes patients could reflect biochemical and molecular heterogeneity with respect to copper availability and utilization in the brain.