mtDNA depletion-like syndrome in Wilson disease

Mitochondrial dysfunction: A promising therapeutic target for liver diseases

The liver is an important metabolic and detoxification organ and hence demands a large amount of energy, which is mainly produced by the mitochondria. Liver tissues of patients with alcohol-related or non-alcohol-related liver diseases contain ultrastructural mitochondrial lesions, mitochondrial DNA damage, disturbed mitochondrial dynamics, and compromised ATP production. Overproduction of mitochondrial reactive oxygen species induces oxidative damage to mitochondrial proteins and mitochondrial DNA, decreases mitochondrial membrane potential, triggers hepatocyte inflammation, and promotes programmed cell death, all of which impair liver function. Mitochondrial DNA may be a potential novel non-invasive biomarker of the risk of progression to liver cirrhosis and hepatocellular carcinoma in patients infected with the hepatitis B virus. We herein present a review of the mechanisms of mitochondrial dysfunction in the development of acute liver injury and chronic liver diseases, such as hepatocellular carcinoma, viral hepatitis, drug-induced liver injury, alcoholic liver disease, and non-alcoholic fatty liver disease. This review also discusses mitochondrion-centric therapies for treating liver diseases.

Copper homeostasis dysregulation promoting cell damage and the association with liver diseases

ABSTRACT

Copper plays an important role in many metabolic activities in the human body. Copper level in the human body is in a state of dynamic equilibrium. Recent research on copper metabolism has revealed that copper dyshomeostasis can cause cell damage and induce or aggravate some diseases by affecting oxidative stress, proteasome, cuprotosis, and angiogenesis. The liver plays a central role in copper metabolism in the human body. Research conducted in recent years has unraveled the relationship between copper homeostasis and liver diseases. In this paper, we review the available evidence of the mechanism by which copper dyshomeostasis promotes cell damage and the development of liver diseases, and identify the future research priorities.

Wilson's disease: best practice

Wilson's disease is an autosomal recessive disorder arising from pathogenic variants in the Atp7b gene on chromosome 13. The defective translated ATPase copper (Cu) transport protein produced leads to Cu accumulation, initially affecting the liver but eventually affecting other cells. It is just over 20 years since the last Best Practice on this topic in this journal. This review is an update on this, covering new disease biomarkers, pathogenesis, assumptions around clinical features and developments in therapy.

Mitochondrial copper in human genetic disorders

Copper is an essential micronutrient that serves as a cofactor for enzymes involved in diverse physiological processes, including mitochondrial energy generation. Copper enters cells through a dedicated copper transporter and is distributed to intracellular cuproenzymes by copper chaperones. Mitochondria are critical copper-utilizing organelles that harbor an essential cuproenzyme cytochrome c oxidase, which powers energy production. Mutations in copper transporters and chaperones that perturb mitochondrial copper homeostasis result in fatal genetic disorders. Recent studies have uncovered the therapeutic potential of elesclomol, a copper ionophore, for the treatment of copper deficiency disorders such as Menkes disease. Here we review the role of copper in mitochondrial energy metabolism in the context of human diseases and highlight the recent developments in copper therapeutics.

Wilson's disease: update on pathogenesis, biomarkers and treatments

Wilson's disease is an autosomal-recessive disorder of copper metabolism caused by mutations in ATP7B and associated with neurological, psychiatric, ophthalmological and hepatic manifestations. Decoppering treatments are used to prevent disease progression and reduce symptoms, but neurological outcomes remain mixed. In this article, we review the current understanding of pathogenesis, biomarkers and treatments for Wilson's disease from the neurological perspective, with a focus on recent advances. The genetic and molecular mechanisms associated with ATP7B dysfunction have been well characterised, but despite extensive efforts to identify genotype-phenotype correlations, the reason why only some patients develop neurological or psychiatric features remains unclear. We discuss pathological processes through which copper accumulation leads to neurodegeneration, such as mitochondrial dysfunction, the role of brain iron metabolism and the broader concept of selective neuronal vulnerability in Wilson's disease. Delayed diagnoses continue to be a major problem for patients with neurological presentations. We highlight limitations in our current approach to making a diagnosis and novel diagnostic biomarkers, including the potential for newborn screening programmes. We describe recent progress in developing imaging and wet (fluid) biomarkers for neurological involvement, including findings from quantitative MRI and other neuroimaging studies, and the development of a semiquantitative scoring system for assessing radiological severity. Finally, we cover the use of established and novel chelating agents, paradoxical neurological worsening, and progress developing targeted molecular and gene therapy for Wilson's disease, before discussing future directions for translational research.

Diagnosis of Wilson Disease and Its Phenotypes by Using Artificial Intelligence

WD is caused by ATP7B variants disrupting copper efflux resulting in excessive copper accumulation mainly in liver and brain. The diagnosis of WD is challenged by its variable clinical course, onset, morbidity, and ATP7B variant type. Currently it is diagnosed by a combination of clinical symptoms/signs, aberrant copper metabolism parameters (e.g., low ceruloplasmin serum levels and high urinary and hepatic copper concentrations), and genetic evidence of ATP7B mutations when available. As early diagnosis and treatment are key to favorable outcomes, it is critical to identify subjects before the onset of overtly detrimental clinical manifestations. To this end, we sought to improve WD diagnosis using artificial neural network algorithms (part of artificial intelligence) by integrating available clinical and molecular parameters. Surprisingly, WD diagnosis was based on plasma levels of glutamate, asparagine, taurine, and Fischer's ratio. As these amino acids are linked to the urea-Krebs' cycles, our study not only underscores the central role of hepatic mitochondria in WD pathology but also that most WD patients have underlying hepatic dysfunction. Our study provides novel evidence that artificial intelligence utilized for integrated analysis for WD may result in earlier diagnosis and mechanistically relevant treatments for patients with WD.