The Role of Glia in Wilson's Disease: Clinical, Neuroimaging, Neuropathological and Molecular Perspectives.

Wilson's disease (WD) is inherited in an autosomal recessive manner and is caused by pathogenic variants of the ATP7B gene, which are responsible for impaired copper transport in the cell, inhibition of copper binding to apoceruloplasmin, and biliary excretion. This leads to the accumulation of copper in the tissues. Copper accumulation in the CNS leads to the neurological and psychiatric symptoms of WD. Abnormalities of copper metabolism in WD are associated with impaired iron metabolism. Both of these elements are redox active and may contribute to neuropathology. It has long been assumed that among parenchymal cells, astrocytes have the greatest impact on copper and iron homeostasis in the brain. Capillary endothelial cells are separated from the neuropil by astrocyte terminal legs, putting astrocytes in an ideal position to regulate the transport of iron and copper to other brain cells and protect them if metals breach the blood-brain barrier. Astrocytes are responsible for, among other things, maintaining extracellular ion homeostasis, modulating synaptic transmission and plasticity, obtaining metabolites, and protecting the brain against oxidative stress and toxins. However, excess copper and/or iron causes an increase in the number of astrocytes and their morphological changes observed in neuropathological studies, as well as a loss of the copper/iron storage function leading to macromolecule peroxidation and neuronal loss through apoptosis, autophagy, or cuproptosis/ferroptosis. The molecular mechanisms explaining the possible role of glia in copper- and iron-induced neurodegeneration in WD are largely understood from studies of neuropathology in Parkinson's disease and Alzheimer's disease. Understanding the mechanisms of glial involvement in neuroprotection/neurotoxicity is important for explaining the pathomechanisms of neuronal death in WD and, in the future, perhaps for developing more effective diagnostic/treatment methods.

Genetic Variants in Matrix Metalloproteinases MMP3 (rs3025058) and MMP9 (rs3918242) Associated with Colonic Diverticulosis.

Background and Objectives: Diverticulosis affects a significant portion of the elderly population, with age and lifestyle being established risk factors. Additionally, genetic predisposition is gaining recognition as a contributing factor. This pilot study sought to explore the frequency of genetic variants in matrix metalloproteinases (MMPs) 3, 9, and 12 in a population of colonic diverticulosis patients. Materials and Methods: The study encompassed 134 participants: 59 diagnosed with colon diverticulosis during colonoscopy and 75 healthy controls. The cases and controls were meticulously matched in terms of age and gender. We assessed the distribution of genetic variants MMP3 rs3025058, MMP9 rs3918242, and MMP12 rs2276109 using the polymerase chain reaction-restriction fragments length polymorphism technique. Results: The MMP9 rs3918242 allele T was notably more frequent in individuals with diverticulosis when compared with the control group (p < 0.03). Furthermore, it was associated with dominant (OR = 2.62; 95% CI: 1.24-5.56; p < 0.01) and co-dominant (OR = 2.10; 95% CI: 1.06-4.13; p < 0.03) genetic models. The MMP3 rs3025058 5A/5A genotype was nearly twice as frequent in patients with diverticulosis, while the 6A/6A genotype was only half as common in this group. Conversely, no significant correlation was established between MMP12 rs2276109 and colonic diverticulosis. Conclusions: Our study offers the first insight into a potential connection between genetic variants in MMPs and colon diverticulosis. Specifically, allele T of MMP9 rs3918242 and allele 5A of MMP3 rs3025058 appear to be linked to this condition. These findings indirectly suggest a role for extracellular matrix proteins in the pathogenesis of diverticulosis.

Effect of homeostatic iron regulator protein gene mutation on Wilson's disease clinical manifestation: original data and literature review.

OBJECTIVE: Wilson's disease (WD) is a hereditary disorder of copper metabolism. The metabolic pathways of copper and iron are interrelated. Our goal was to determine the frequency of the two most common mutations in the coding region of the human iron homeostatic protein gene (HFE) in Europe: C282Y (rs1800562) and H63D (rs1799945) in WD patients, as well as to analyze their relation with WD phenotypic traits. MATERIAL AND METHODS: HFE mutations were studied by PCR RFLP method in 445 WD patients and 102 controls. All patients met the diagnostic criteria of WD 8th International Conference on Wilson Disease and Menkes Disease. RESULTS: HFE C282Y heterozygotes, both women and men, showed WD symptoms earlier than patients with wild-type HFE genotype. HFE 63HD heterozygous men presented symptoms later than HFE 63HH homozygotes, but HFE 63HD women manifested symptoms later than those with HFE 63HH genotype. CONCLUSIONS: HFE genotype seems to be one of the factors modifying Wilson's disease phenotype.

Psychometric validation of the Polish version of the Central Sensitization Inventory in subjects with chronic spinal pain.

BACKGROUND: Central sensitization is an amplification of neuronal signaling within the central nervous system. The Central Sensitization Inventory was introduced in 2012. A Polish version of the CSI (CSI-Pol) was developed in 2019, but it was not psychometrically validated. The aim of this study was to validate the CSI-Pol in a sample of Polish-speaking patients with chronic spinal pain and compare them with a group of healthy control subjects. METHODS: The CSI-Pol was administered to 151 patients with chronic spinal pain recruited from two centers. It was re-administered 7 days later. The psychometric properties were then evaluated, including test-retest reliability, construct validity, factor structure and internal consistency. We correlated the CSI-Pol with functional scales, depression and social support scales and compared CSI-Pol scores in the clinical subjects with 30 healthy control subjects recruited from medical staff and their families. RESULTS: The CSI-Pol demonstrated excellent internal consistency (Cronbach's α =0,933) and test-retest reliability (Intraclass Correlation Coefficients - ICC =0.96), as well as significant positive associations with other patient-reported scales, including the Neck Disability Index (r = 0.593), Revised Oswestry Low Back Pain Disability Questionnaire (r = 0.422), and other measures of functional and depressive states. An exploratory factor analysis resulted in a 4-factor model. CSI-Pol scores in the clinical sample (35.27 ± 17.25) were significantly higher than the control sample (23.3 ± 8.9). CONCLUSION: The results of this study suggest that the CSI-Pol may be a useful clinical tool for assessing central sensitization related symptoms and guiding appropriate treatment in Polish-speaking patients with spinal pain.

Iron metabolism is disturbed and anti-copper treatment improves but does not normalize iron metabolism in Wilson's disease.

Wilson's disease (WD) is a rare hereditary disorder of copper metabolism. Some data suggest that iron metabolism is disturbed in WD and this may affect the course of the disease. The current study aimed to determine whether anti-copper treatment could affect iron metabolism in WD. One hundred thirty-eight WD patients and 102 controls were examined. Serum ceruloplasmin and copper were measured by colorimetric enzyme assay or atomic adsorption spectroscopy, respectively. Routine and non-routine parameters of iron metabolism were measured by standard laboratory methods or enzyme immunoassay, respectively. WD patients, both newly diagnosed and treated, had less serum copper and ceruloplasmin than controls (90.0, 63.0, 22.0 mg/dL, respectively, p < 0.001); in the treated patients blood copper and ceruloplasmin were lower than in untreated patients (p < 0.001). Untreated patients (n = 39) had a higher median blood iron (126.0 vs 103.5 ug/dL, p < 0.05), ferritin (158.9 vs 47.5 ng/mL, p < 0.001), hepcidin (32, 6 vs 12.1 ng/mL, p < 0.001) and sTfR (0.8 vs. 0.7 ug/mL, p < 0.001) and lower blood transferrin (2.4 vs. 2.7 g/L, p < 0.001), TIBC (303.0 vs 338.0 ug/dL, p < 0.001), hemoglobin (13.1 vs 13.9 g/dL, p < 0.01) and RBC (4.3 vs. 4.6, p < 0.002) than controls. Treated patients (n = 99) had a significantly lower median iron (88.0 vs. 126.0 ug/dL, p < 0.001), ferritin (77.0 vs. 158.9 ng/mL, p < 0.005) and hepcidin (16.7 vs. 32.6 ng/mL, p < 001) and higher transferrin (2.8 vs. 2.4 g/L, p < 0.005), TIBC (336.0 vs 303.0 ug/dL, p < 0.001), RBC (4.8 vs. 4.3 M/L, p < 0.001) and hemoglobin (14.4 vs. 13.1 g/dL, p < 0.001) than untreated; the median iron (p < 0.005) was lower, and ferritin (p < 0.005), RBC (p < 0.005) and hepcidin (p < 0.002) were higher in them than in the control group. Changes in copper metabolism are accompanied by changes in iron metabolism in WD. Anti-copper treatment improves but does not normalize iron metabolism.

Copper Dyshomeostasis in Neurodegenerative Diseases-Therapeutic Implications.

Copper is one of the most abundant basic transition metals in the human body. It takes part in oxygen metabolism, collagen synthesis, and skin pigmentation, maintaining the integrity of blood vessels, as well as in iron homeostasis, antioxidant defense, and neurotransmitter synthesis. It may also be involved in cell signaling and may participate in modulation of membrane receptor-ligand interactions, control of kinase and related phosphatase functions, as well as many cellular pathways. Its role is also important in controlling gene expression in the nucleus. In the nervous system in particular, copper is involved in myelination, and by modulating synaptic activity as well as excitotoxic cell death and signaling cascades induced by neurotrophic factors, copper is important for various neuronal functions. Current data suggest that both excess copper levels and copper deficiency can be harmful, and careful homeostatic control is important. This knowledge opens up an important new area for potential therapeutic interventions based on copper supplementation or removal in neurodegenerative diseases including Wilson's disease (WD), Menkes disease (MD), Alzheimer's disease (AD), Parkinson's disease (PD), and others. However, much remains to be discovered, in particular, how to regulate copper homeostasis to prevent neurodegeneration, when to chelate copper, and when to supplement it.

Distinct phenotype of a Wilson disease mutation reveals a novel trafficking determinant in the copper transporter ATP7B.

Wilson disease (WD) is a monogenic autosomal-recessive disorder of copper accumulation that leads to liver failure and/or neurological deficits. WD is caused by mutations in ATP7B, a transporter that loads Cu(I) onto newly synthesized cupro-enzymes in the trans-Golgi network (TGN) and exports excess copper out of cells by trafficking from the TGN to the plasma membrane. To date, most WD mutations have been shown to disrupt ATP7B activity and/or stability. Using a multidisciplinary approach, including clinical analysis of patients, cell-based assays, and computational studies, we characterized a patient mutation, ATP7B(S653Y), which is stable, does not disrupt Cu(I) transport, yet renders the protein unable to exit the TGN. Bulky or charged substitutions at position 653 mimic the phenotype of the patient mutation. Molecular modeling and dynamic simulation suggest that the S653Y mutation induces local distortions within the transmembrane (TM) domain 1 and alter TM1 interaction with TM2. S653Y abolishes the trafficking-stimulating effects of a secondary mutation in the N-terminal apical targeting domain. This result indicates a role for TM1/TM2 in regulating conformations of cytosolic domains involved in ATP7B trafficking. Taken together, our experiments revealed an unexpected role for TM1/TM2 in copper-regulated trafficking of ATP7B and defined a unique class of WD mutants that are transport-competent but trafficking-defective. Understanding the precise consequences of WD-causing mutations will facilitate the development of advanced mutation-specific therapies.

Gene variants encoding proteins involved in antioxidant defense system and the clinical expression of Wilson disease.

BACKGROUND & AIMS: Wilson disease (WD) is an autosomal recessive disorder of copper metabolism resulting from pathogenic mutations of the ATP7B gene. The basis of phenotypic variability of the disease is not understood. The main mechanism of copper toxicity is probably related to generation of intracellular oxidative stress. To evaluate whether interindividual variability within genes encoding proteins involved in antioxidant defense system may modulate phenotypic expressions of WD. METHODS: Variability within genes encoding the cytosolic enzymes: glutathione peroxidase (GPX1 rs1050450) and manganese superoxide dismutase (SOD2 rs4880), and peroxisomal enzyme: catalase (CAT rs1001179) were analysed in 435 patients. Individual genotypes were tested for their relationship with phenotypic features of WD. RESULTS: GPX1 genotypes were not related to phenotypic manifestations of WD. Among males homozygocity for the SOD2 rs4880 T allele was related to earlier onset of WD. Patients homozygous for the CAT rs1001179 T allele characterized with later onset of WD [median (interquartile range) age: 29.0 (14.0) years vs. 22.0 (12.0) years, respectively, P < 0.004], later manifestation of hepatic symptoms [34.5 (14.0) years vs. 22.0 (12.0) years, P < 0.0009], and later presentation of neurological symptoms [37.0 (16.0) years vs. 28.0 (13.0) years, P < 0.03] than those having one or two C alleles. CONCLUSION: Variability within the CAT gene may be an important modifier of the clinical course of WD. SOD2 genotype may influence WD phenotype among males. These observations indirectly confirm a role of oxidative stress in the pathogenesis of WD, as well as indirectly suggest that peroxisomes impairment may be involved in WD pathophysiology.

The activity of malignancy may determine stroke pattern in cancer patients.

BACKGROUND: It has been suggested that stroke in patients with cancer may differ from the conventional pattern. The aim of this study was to evaluate the burden of vascular risk factors, stroke etiology, and short-term outcome in patients with active and nonactive malignancy compared with patients without cancer. METHODS: This is a prospective cohort study of consecutive acute stroke patients admitted to our department between September 2006 and September 2011. We distinguished between the following: (1) patients with active malignancy (AM, diagnosed not earlier than 12 months before stroke); (2) patients with nonactive malignancy (non-AM); and (3) cancer-free (CF) patients, used as a reference. RESULTS: Pre-existing cancer was found in 90 of 1558 patients, including 41 (2.6%) cases with AM and 49 (3.1%) cases with non-AM. Compared with CF patients, AM patients less frequently had a history of previous stroke (2.4% versus 17.9%, P = .018) and more frequently experienced ischemic strokes of undetermined etiology (62.5% versus 38.3%, P = .002). Non-AM patients did not differ in the distribution of vascular risk factors but more often experienced stroke caused by small vessel occlusion (20.0% versus 8.0%, P = .004). Inflammatory blood markers were elevated especially in patients with AM. Short-term prognosis was similar across all groups. CONCLUSIONS: Stroke pattern in patients with non-AM appears very similar to that observed in the CF patients. However, our findings support the thesis that cancer-specific prothrombotic mechanisms play an important role in stroke patients with AM, which may be related to active inflammatory and immune processes. Malignancy does not influence short-term prognosis of stroke.

Treatment with D-penicillamine or zinc sulphate affects copper metabolism and improves but not normalizes antioxidant capacity parameters in Wilson disease.

Copper accumulation in tissues due to a biallelic pathogenic mutation of the gene: ATP7B results in a clinical phenotype known as Wilson disease (WD). Aberrations in copper homeostasis can create favourable conditions for superoxide-yielding redox cycling and oxidative tissue damage. Drugs used in WD treatment aim to remove accumulated copper and normalise the free copper concentration in the blood. In the current study the effect of decoppering treatment on copper metabolism and systemic antioxidant capacity parameters was analyzed. Treatment naïve WD patients (TNWD) (n = 33), those treated with anti-copper drugs (TWD) (n = 99), and healthy controls (n = 99) were studied. Both TNWD and TWD patients characterised with decreased copper metabolism parameters, as well as decreased total antioxidant potential (AOP), glutathione (GSH) level, activity of catalase, glutathione peroxidase (GPx), and S-transferase glutathione, compared to controls. TWD patients had significantly lower copper metabolism parameters, higher total AOP and higher levels of GSH than TWD individuals; however, no difference was observed between these two patient groups with respect to the rest of the antioxidant capacity parameters. Patients who had undergone treatment with D-penicillamine or zinc sulphate did not differ with respect to copper metabolism or antioxidant capacity parameters, with the exception of GPx that was lower in D-penicillamine treated individuals. These data suggest that anti-copper treatment affects copper metabolism as well as improves, but does not normalize, natural antioxidant capacity in patients with WD. We propose to undertake studies aimed to evaluate the usefulness of antioxidants as well as selenium as a supplemental therapy in WD.

Impact of BDNF -196 G>A and BDNF -270 C>T polymorphisms on stroke rehabilitation outcome: sex and age differences.

BACKGROUND: Genetic factors, including gene polymorphisms, are promising in determining stroke rehabilitation outcome. Brain-derived neurotrophic factor (BDNF) is one of the most attractive because of its role in neuroplasticity and brain repair. OBJECTIVE: The aim of present study was to assess the role of BDNF -196 G≯A (val66met) and -270 C≯T on clinical parameters and functional outcome in patients with ischemic and hemorrhagic stroke. Additional analyses according to sex and age (≤55 and ≯55 years) were performed. METHODS: Three hundred thirty-eight patients (287 with ischemic and 51 with hemorrhagic stroke) were evaluated in terms of neurological deficit (National Institute of Heath Stroke Scale [NIHSS]), activities of daily living (Barthel Index [BI]), and everyday functionality (Rankin score [RS]) before and after rehabilitation. BDNF polymorphism genotyping was performed by polymerase chain reaction restriction fragment length polymorphism analysis. RESULTS: In multivariative analysis, unfavorable outcome of stroke rehabilitation (RS ≥2) was associated with independent factors: ischemic stroke (odds ratio [OR], 2.59; 95% CI, 1.03-6.47), female gender (OR, 2.80; 95% CI, 1.39-5.64), depression (OR, 4.24; 95% CI, 1.45-12.35), falls (OR, 2.61; 95% CI, 1.16-5.87), and BDNF -196 GG polymorphism (OR, 2.18; 95% CI, 1.09-4.35). The differences of functional parameters measured with BI and RS on admission and at discharge are apparent only for comparisons between patients ≤55 and ≯55 years old carrying BDNF -196 GA+AA genotypes but not in those carrying -196 GG genotype; the differences were evident in women but not in men. CONCLUSIONS: BDNF -196 G≯A polymorphism might affect functional outcome of stroke rehabilitation, but this hypothesis needs further verification.

[Ceruloplasmin, hephaestin and zyklopen: the three multicopper oxidases important for human iron metabolism]. / Ceruloplazmina, hefajstyna i cyklopen:trzy multimiedziowe oksydazy uczestniczace w metabolizmie zelaza u czlowieka.

Multi-copper oxidases are a group of proteins which demonstrate enzymatic activity and are capable of oxidizing their substrates with the concomitant reduction of dioxygen to two water molecules. For some multi-copper oxidases there has been demonstrated ferroxidase activity which is related to their specific structure characterized by the presence of copper centres and iron-binding sites. Three multi-copper oxidases have been included in this group: ceruloplasmin, hephaestin and zyklopen. Multi-copper oxidases which are expressed in different tissues are capable of oxidizing a wide spectrum of substrates. Multi-copper oxidases are capable of oxidizing a wide spectrum of substrates. Ceruloplasmin exhibits antioxidant activity as well as being involved in many other biological processes. The observations of phenotypic effects of absence or low expression of multi-copper ferroxidase-coding genes suggest that the main role of these proteins is taking part in iron metabolism. The main role of ceruloplasmin in iron turnover is oxidizing Fe2+ into Fe3+, a process which is essential for iron binding to transferrin (the main iron-transporting protein), as well as to ferritin (the main iron-storage protein). The function of hephaestin as ferroxidase is essential for iron binding to apotransferrin in the lamina propria of the intestinal mucosa, a process that is important for further transport of iron to the liver by the portal vein. Available data indicate that zyklopen is responsible for the placental iron transport. The presence of three multi-copper oxidases with ferroxidase activity emphasizes the significance of oxidation for iron metabolism. The distribution of multi-copper ferroxidases in many tissues ensures the proper iron turnover in the body as well as preventing toxic effects related to the presence of Fe2+ ions. These ions contribute to generation of free radicals, including the highly reactive hydroxyl radical, through the Fenton and Haber-Weiss reactions.

Neurochemical and behavioral characteristics of toxic milk mice: an animal model of Wilson's disease.

Toxic milk mice have an inherited defect of copper metabolism. Hepatic phenotype of the toxic milk mice is similar to clinical findings in humans suffering from Wilson's disease (WND). In the present study, neurotransmitter system and locomotor performance in toxic milk mice was examined to verify the feasibility of this animal model for studying neuropathology of WND. Mice aged 2 and 12 months were used in the experiment. The mice were tested according to rotarod and footprint protocols. Monoamine content in brain structures was measured by high performance liquid chromatography. In order to detect neuronal loss, expression of enzymes specific for dopaminergic [tyrosine hydroxylase (TH)], noradrenergic (dopamine beta-hydroxylase) and serotoninergic [tryptophan hydroxylase (TPH)] neurons was analyzed by Western blot. The 12-month-old toxic milk mice demonstrated impaired locomotor performance in behavioral tests. Motor deficits were accompanied by increased copper and serotonin content in different brain regions and slight decrease in dopamine concentration in the striatum. The expression of TH, dopamine beta-hydroxylase and TPH in the various brain structures did not differ between toxic milk mice and control animals. Despite differences in brain pathology between humans and rodents, further exploration of neuronal injury in toxic milk mice is warranted to broaden the understanding of neuropathology in WND.

Intestinal expression of metal transporters in Wilson's disease.

In Wilson's disease (WND), biallelic ATP7B gene mutation is responsible for pathological copper accumulation in the liver, brain and other organs. It has been proposed that copper transporter 1 (CTR1) and the divalent metal transporter 1 (DMT1) translocate copper across the human intestinal epithelium, while Cu-ATPases: ATP7A and ATP7B serve as copper efflux pumps. In this study, we investigated the expression of CTR1, DMT1 and ATP7A in the intestines of both WND patients and healthy controls to examine whether any adaptive mechanisms to systemic copper overload function in the enterocytes. Duodenal biopsy samples were taken from 108 patients with Wilson's disease and from 90 controls. CTR1, DMT1, ATP7A and ATP7B expression was assessed by polymerase chain reaction and Western blot. Duodenal CTR1 mRNA and protein expression was decreased in WND patients in comparison to control subjects, while ATP7A mRNA and protein production was increased. The variable expression of copper transporters may serve as a defense mechanism against systemic copper overload resulting from functional impairment of ATP7B.

Influence of BDNF polymorphisms on Wilson's disease susceptibility and clinical course.

Susceptibility to Wilson's disease (WD) and its clinical manifestations are thought to be affected by genetic factors, including polymorphisms. The role of brain-derived neurotrophic factor (BDNF) in the pathogenesis of neurodegenerative diseases is now widely discussed. The aim of the present study was to evaluate the frequency of the BDNF Val66Met (G-196A) and C-270T polymorphisms in WD patients and in healthy controls, and to determine the role of these polymorphisms in the clinical characteristics of WD. We found that the BDNF Val/Val (-196 G/G) and -270 C/T genotypes occurred more frequently in WD patients than in healthy controls (66 % versus 45.5 %, p = 0.0001, and 14 % versus 6 %, p = 0.018, respectively). Similarly, symptomatic patients carried the BDNF Val/Val genotype more often than presymptomatic patients (75 % versus 53 %, p = 0.0097). No association was detected between any of the determined polymorphisms and the dominant form of the disease or the age of onset for WD.

Prestroke antihypertensive therapy: effect on the outcome.

About 70% of stroke patients have a history of hypertension. Patients with hypertension prior to stroke onset have higher blood pressure in the acute phase of stroke than non-hypertensive individuals. High blood pressure in the acute stroke adversely affects outcome. We analyzed 30-days outcome in 1306 hypertensive patients with ischemic stroke, of which 1069 (81.8%) received antihypertensive treatment before stroke onset. Multivariate logistic regression revealed that prestroke use of antihypertensives is an independent predictor of better stroke outcome, in terms of dependency and death or dependency. We conclude that increased efforts toward optimizing hypertension diagnostics and control are needed.

[Oxidative stress and natural antioxidant mechanisms: the role in neurodegeneration. From molecular mechanisms to therapeutic strategies]. / Stres oksydacyjny i naturalne mechanizmy antyoksydacyjne ­ znaczenie w procesie neurodegeneracji. Od mechanizmów molekularnych do strategii terapeutycznych.

A lot of evidence exists that oxidative stress is the primary cause of neurodegeneration. Neurons are more susceptible to oxidative damage than other cells due to their high oxygen consumption, low activity of antioxidant enzymes, elevated concentration of polyunsaturated fatty acids in the cell membrane, high number of mitochondria, unfavorable space/volume ratio and vicinity of microglia cells which are likely to produce increased amounts of superoxide radical. Moreover, the tendency to accumulate transition metals in the brain creates a higher probability of Fenton's reaction occurring, a product of which is a hydroxyl radical. Lower activities of natural antioxidants as well as higher concentrations of markers of oxidative damage to proteins, lipids and DNA were observed in patients with neurodegenerative diseases in relation to healthy individuals. There is a lot of research being conducted to develop effective and safe antioxidants that would be useful in the therapy or prevention of neurodegenerative diseases.  

Wilson's Disease-Genetic Puzzles with Diagnostic Implications.

(1) Introduction: Wilson's disease (WND) is an autosomal recessive disorder of copper metabolism. The WND gene is ATP7B, located on chromosome 13. WND is characterized by high clinical variability, which causes diagnostic difficulties. (2) Methods: The PubMed, Science Direct, and Wiley Online Library medical databases were reviewed using the following phrases: "Wilson's disease", "ATP7B genotype", "genotype-phenotype", "epigenetics", "genetic modifiers", and their combinations. Publications presenting the results of experimental and clinical studies, as well as review papers, were selected, which concerned: (i) the diversity of genetic strategies and tests used in WND diagnosis; (ii) the difficulties of genetic diagnosis, including uncertainty as to the pathogenicity of variants; (iii) genetic counseling; (iv) phenotypic effects of ATP7B variants in patients with WND and in heterozygous carriers (HzcWND); (v) genetic and epigenetics factors modifying the clinical picture of the disease. (3) Results and conclusions: The genetic diagnosis of WND is carried out using a variety of strategies and tests. Due to the large number of known variants in the ATP7B gene (>900), the usefulness of genetic tests in routine diagnostics is still relatively small and even analyses performed using the most advanced technologies, including next-generation sequencing, require additional tests, including biochemical evidence of abnormal copper metabolism, to confirm the diagnosis of WND. Pseudodominant inheritance, the presence of three various pathogenic variants in the same patient, genotypes indicating the possibility of segmental uniparental disomy, have been reported. Genotype-phenotype relationships in WND are complex. The ATP7B genotype, to some extent, determines the clinical picture of the disease, but other genetic and epigenetic modifiers are also relevant.

Antioxidant Capacity Is Decreased in Wilson's Disease and Correlates to Liver Function.

The metabolic disorder Wilson's disease (WD) is caused by copper accumulation in the tissues due to a biallelic pathogenic mutation of the gene ATP7B, encoding intracellular copper transporter ATPase-7B. As copper is a redox active metal; aberrations in its homeostasis may create favourable conditions for superoxide-yielding redox cycling and oxidative damage to the cells. We tried to characterise antioxidant defence in WD patients and to evaluate whether it is related to liver function. The blood glutathione concentration, the activity of manganese-SOD (MnSOD), catalase (Cat), glutathione peroxidase, and glutathione S-transferase glutathione (GST), and serum antioxidant potential (AOP-450) were measured in WD treatment-naive patients and healthy controls and correlated with clinical data. The blood glutathione concentration, the activity of MnSOD, Cat, glutathione peroxidase, and GST and AOP-450 are significantly decreased in WD patients. There was a positive correlation of AOP-450 with AST. Moreover, the Cat and GST activity as well as AOP-450 strongly correlated with parameters of synthetic liver function. MnSOD activity correlated positively with ALT and AST.The blood glutathione concentration, the activity of MnSOD, Cat, glutathione peroxidase, and GST and AOP-450 are significantly decreased in WD patients. There was a positive correlation of AOP-450 with AST. Moreover, the Cat and GST activity as well as AOP-450 strongly correlated with parameters of synthetic liver function. MnSOD activity correlated positively with ALT and AST. Liver injury in course of WD is linked with decreased antioxidant capacity.

Monitoring of Copper in Wilson Disease.

(1) Introduction: Wilson's disease (WND) is an autosomal recessive disorder of copper (Cu) metabolism. Many tools are available to diagnose and monitor the clinical course of WND. Laboratory tests to determine disorders of Cu metabolism are of significant diagnostic importance. (2) Methods: A systematic review of the literature in the PubMed, Science Direct, and Wiley Online Library databases was conducted. (Results): For many years, Cu metabolism in WND was assessed with serum ceruloplasmin (CP) concentration, radioactive Cu test, total serum Cu concentration, urinary copper excretion, and Cu content in the liver. The results of these studies are not always unambiguous and easy to interpret. New methods have been developed to calculate non-CP Cu (NCC) directly. New parameters, such as relative Cu exchange (REC), reflecting the ratio of CuEXC to total serum Cu, as well as relative Cu exchange (REC), reflecting the ratio of CuEXC to total serum Cu, have been shown to be an accurate tool for the diagnosis of WND. Recently, a direct and fast LC-ICP-MS method for the study of CuEXC was presented. A new method to assess Cu metabolism during treatment with ALXN1840 (bis-choline tetrathiomolybdate [TTM]) has been developed. The assay enables the bioanalysis of CP and different types of Cu, including CP-Cu, direct NCC (dNCC), and labile bound copper (LBC) in human plasma. Conclusions: A few diagnostic and monitoring tools are available for patients with WND. While many patients are diagnosed and adequately assessed with currently available methods, diagnosis and monitoring is a real challenge in a group of patients who are stuck with borderline results, ambiguous genetic findings, and unclear clinical phenotypes. Technological progress and the characterization of new diagnostic parameters, including those related to Cu metabolism, may provide confidence in the more accurate diagnosis of WND in the future.