Clinical zinc deficiency as early presentation of Wilson disease

Wilson Disease: Copper-Mediated Cuproptosis, Iron-Related Ferroptosis, and Clinical Highlights, with Comprehensive and Critical Analysis Update

Wilson disease is a genetic disorder of the liver characterized by excess accumulation of copper, which is found ubiquitously on earth and normally enters the human body in small amounts via the food chain. Many interesting disease details were published on the mechanistic steps, such as the generation of reactive oxygen species (ROS) and cuproptosis causing a copper dependent cell death. In the liver of patients with Wilson disease, also, increased iron deposits were found that may lead to iron-related ferroptosis responsible for phospholipid peroxidation within membranes of subcellular organelles. All topics are covered in this review article, in addition to the diagnostic and therapeutic issues of Wilson disease. Excess Cu2+ primarily leads to the generation of reactive oxygen species (ROS), as evidenced by early experimental studies exemplified with the detection of hydroxyl radical formation using the electron spin resonance (ESR) spin-trapping method. The generation of ROS products follows the principles of the Haber-Weiss reaction and the subsequent Fenton reaction leading to copper-related cuproptosis, and is thereby closely connected with ROS. Copper accumulation in the liver is due to impaired biliary excretion of copper caused by the inheritable malfunctioning or missing ATP7B protein. As a result, disturbed cellular homeostasis of copper prevails within the liver. Released from the liver cells due to limited storage capacity, the toxic copper enters the circulation and arrives at other organs, causing local accumulation and cell injury. This explains why copper injures not only the liver, but also the brain, kidneys, eyes, heart, muscles, and bones, explaining the multifaceted clinical features of Wilson disease. Among these are depression, psychosis, dysarthria, ataxia, writing problems, dysphagia, renal tubular dysfunction, Kayser-Fleischer corneal rings, cardiomyopathy, cardiac arrhythmias, rhabdomyolysis, osteoporosis, osteomalacia, arthritis, and arthralgia. In addition, Coombs-negative hemolytic anemia is a key feature of Wilson disease with undetectable serum haptoglobin. The modified Leipzig Scoring System helps diagnose Wilson disease. Patients with Wilson disease are well-treated first-line with copper chelators like D-penicillamine that facilitate the removal of circulating copper bound to albumin and increase in urinary copper excretion. Early chelation therapy improves prognosis. Liver transplantation is an option viewed as ultima ratio in end-stage liver disease with untreatable complications or acute liver failure. Liver transplantation finally may thus be a life-saving approach and curative treatment of the disease by replacing the hepatic gene mutation. In conclusion, Wilson disease is a multifaceted genetic disease representing a molecular and clinical challenge.

Copper Toxicity Is Not Just Oxidative Damage: Zinc Systems and Insight from Wilson Disease

Essential metals such as copper (Cu) and zinc (Zn) are important cofactors in diverse cellular processes, while metal imbalance may impact or be altered by disease state. Cu is essential for aerobic life with significant functions in oxidation-reduction catalysis. This redox reactivity requires precise intracellular handling and molecular-to-organismal levels of homeostatic control. As the central organ of Cu homeostasis in vertebrates, the liver has long been associated with Cu storage disorders including Wilson Disease (WD) (heritable human Cu toxicosis), Idiopathic Copper Toxicosis and Endemic Tyrolean Infantile Cirrhosis. Cu imbalance is also associated with chronic liver diseases that arise from hepatitis viral infection or other liver injury. The labile redox characteristic of Cu is often discussed as a primary mechanism of Cu toxicity. However, work emerging largely from the study of WD models suggests that Cu toxicity may have specific biochemical consequences that are not directly attributable to redox activity. This work reviews Cu toxicity with a focus on the liver and proposes that Cu accumulation specifically impacts Zn-dependent processes. The prospect that Cu toxicity has specific biochemical impacts that are not entirely attributable to redox may promote further inquiry into Cu toxicity in WD and other Cu-associated disorders.

Zinc against COVID-19? Symptom surveillance and deficiency risk groups

A wide variety of symptoms is associated with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, and these symptoms can overlap with other conditions and diseases. Knowing the distribution of symptoms across diseases and individuals can support clinical actions on timelines shorter than those for drug and vaccine development. Here, we focus on zinc deficiency symptoms, symptom overlap with other conditions, as well as zinc effects on immune health and mechanistic zinc deficiency risk groups. There are well-studied beneficial effects of zinc on the immune system including a decreased susceptibility to and improved clinical outcomes for infectious pathogens including multiple viruses. Zinc is also an anti-inflammatory and anti-oxidative stress agent, relevant to some severe Coronavirus Disease 2019 (COVID-19) symptoms. Unfortunately, zinc deficiency is common worldwide and not exclusive to the developing world. Lifestyle choices and preexisting conditions alone can result in zinc deficiency, and we compile zinc risk groups based on a review of the literature. It is also important to distinguish chronic zinc deficiency from deficiency acquired upon viral infection and immune response and their different supplementation strategies. Zinc is being considered as prophylactic or adjunct therapy for COVID-19, with 12 clinical trials underway, highlighting the relevance of this trace element for global pandemics. Using the example of zinc, we show that there is a critical need for a deeper understanding of essential trace elements in human health, and the resulting deficiency symptoms and their overlap with other conditions. This knowledge will directly support human immune health for decreasing susceptibility, shortening illness duration, and preventing progression to severe cases in the current and future pandemics.

Oxidative stress and neurobehavioural changes in rats following copper exposure and their response to MiADMSA and d-penicillamine

An increase in copper concentration in body may lead to hepatolenticular degeneration which is considered as one clinical feature of Wilson’s disease. Chelation therapy using d-penicillamine is the preferred medical treatment for reducing the toxic effects of copper. However, a few shortcomings associated with d-penicillamine led us to search of an alternative antidote for copper toxicity. Monoisoamyl-2, 3-dimercaptosuccinic acid (MiADMSA), a potent arsenic chelator under clinical trial, has been reported to reduce system copper level. Thus, the present study was envisaged to explore the ameliorative effect of MiADMSA against copper toxicity. Copper pre-exposed animals (CuSO4.5H2O; 100 mg/kg; p.o., for 6 weeks) were segregated in different groups and were administered equimolar dose (0.3 mEq/kg/day; p.o.) of d-penicillamine and MiADMSA for 5 days. The effect of different treatments on spontaneous locomotor activity, muscle coordination, depression like behaviour and contextual fear memory was analysed using neurobehavioural battery test. Biochemical variables related to oxidative stress, zinc and copper concentration were determined in liver, kidney and brain. The results suggested that copper exposure led to oxidative stress in liver, kidney and blood, along with moderate effects in brain. Treatment with d-penicillamine and MiADMSA reduced liver copper load. MiADMSA produced more pronounced beneficial effect compared to d-penicillamine by increasing brain GPx activity. Our study suggests that MiADMSA might be equally effective as d-penicillamine in depleting body copper load. More detailed studies using different doses are required to suggest whether MiADMSA could be an alternative for d-penicillamine in reducing oxidative injury, neurobehavioural changes and depleting body copper burden.

Value of Serum Zinc in Diagnosing and Assessing Severity of Liver Disease in Children With Wilson Disease

OBJECTIVES

Wilson disease (WD) is a rare inborn error of copper metabolism with diverse manifestations. There has been no study of zinc (Zn), the copper's antagonist, in WD diagnosis and severity so far. Our aims were to evaluate serum Zn in WD and its correlation with the disease severity score (revised WD index). Although the ATP7B mutation analysis is highly accurate for WD diagnosis, it may not be readily available in a resource-limiting setting. We proposed a disease diagnostic score (Proposed WD diagnostic score) which incorporates serum Zn.

METHODS

Medical records of WD and non-WD children seen at King's College Hospital from 2005 to 2015 were reviewed for the selected parameters using the Proposed WD diagnostic score. Available serum Zn data in WD children before disease diagnosis and the calculated severity score were statistically analyzed. Diagnostic values of the Proposed WD diagnostic score were evaluated.

RESULTS

Serum Zn level was significantly lower in 8 WD-acute liver failure (ALF) (5.8 [4.1-8.3] μmol/L) compared to 18 WD-non-ALF (13.5 [6.1-22.2] μmol/L) and 9 ALF from indeterminate cause (9.8 [7.0-12.1] μmol/L) (P < 0.001). Serum Zn significantly correlated with the revised WD index (r = -0.554, P = 0.004). The Proposed WD diagnostic score that included serum Zn level as 1 of the parameters had sensitivity and specificity of 87% and 99.2%, respectively.

CONCLUSIONS

Serum Zn is a novel parameter for diagnosis and correlates with severity of WD. The Proposed WD diagnostic score is useful while awaiting ATP7B mutation analysis.

Pediatric Wilson's disease: findings in different presentations. A cross-sectional study

BACKGROUND

Wilson's disease (WD) may present with different manifestations: from an asymptomatic state to liver cirrhosis. Here, we aimed to evaluate clinical presentations and laboratory findings and prognoses among WD cases.

DESIGN AND SETTING

Cross-sectional study based on patients' records from the university hospital, İnönü University, Malatya, Turkey.

METHODS

The medical records of 64 children with WD were evaluated focusing on the clinical, laboratory and liver biopsy findings in different clinical presentations.

RESULTS

The mean age at diagnosis was 8.6 ± 3.26 years (range 3.5-17) and mean length of follow-up was 2.49 years (range 0-9). There were 18 cases (28.1%), 12 (18.8%), 9 (14.1%) and 6 (9.4%) of chronic liver disease, fulminant liver failure, neurological WD and acute hepatitis, respectively. Nineteen (29.7%) were asymptomatic. The most common sign and laboratory finding were jaundice (45.3%) and hypertransaminasemia (85.9%), respectively. The lowest serum zinc level was found in the fulminant liver failure group (P = 0.035). Hepatosteatosis was detected in 35% of the 20 patients who underwent liver biopsy. Among those with hepatosteatosis, 57.1% were asymptomatic. While 35% had copper staining, 25% presented iron accumulation in liver biopsies. Nine cases underwent liver transplantation and seven of these presented fulminant liver failure (77.8%).

CONCLUSION

The presentation, symptoms and signs of our cases were similar to those in previously reported series, except for the high proportion of fulminant WD cases. Further studies are needed to clarify the relationship between zinc levels and development of a fulminant course and between iron status and WD.

The Study on the Correlation Between Six Kinds of Mineral Elements and Diabetes

The study aimed to explore the relationship of six kinds of mineral elements and diabetes among adults in northeast China. A cross-sectional survey was conducted in Jilin Province, northeast China. A total of 366 males and 204 females aged 18 ~ 77 years from Jingyu town, Dongliao town, and Changling town were included using a multistage stratified random cluster sampling design. Data was obtained from face to face interview, physical examination, and laboratory measurement. We defined the normal people (3.9 ~ 6.0 mmol/L), impaired fasting glucose (IFG) individuals (6.1 ~ 6.9 mmol/L), and diabetes mellitus (DM) (> 7.0 mmol/L) according to the WHO diagnostic criteria. Kruskal-Wallis test, Spearman rank correlation, as well as binary logistic regression were used to analyze influencing factors. lg(Cu/Zn)was correlated with DM (OR 8.390; 95% CI of OR 1.272-55.347). The specific mineral elements such as Zn, Ca, as well as Cu/Zn ratio may be the potential risk factors for diabetes. So, the supplement or reduction of these elements is supposed to be told to IFG to prevent or delay the occurrence of diabetes or DM to avoid its complication.