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PubMed · 9727700

Aceruloplasminemia.

Abstract

Aceruloplasminemia is an autosomal recessive disorder of iron metabolism characterized by diabetes, retinal degeneration, and neurologic symptoms. Affected patients evidence marked parenchymal iron accumulation in conjunction with an absence of circulating serum ceruloplasmin and molecular genetic analysis reveals inherited mutations in the ceruloplasmin gene. Taken together with earlier studies that characterized ceruloplasmin as a ferroxidase and recent work indicating an essential role for a homologous multicopper oxidase in iron metabolism in Saccharomyces cerevisiae, these findings reveal an essential role for ceruloplasmin in human iron metabolism. The presence of neurologic symptoms in patients with aceruloplasminemia is unique among the characterized disorders of iron metabolism, and recent findings indicate that astrocyte-specific ceruloplasmin gene expression is critical for iron metabolism and neuronal survival in the retina and basal ganglia. The discovery of this disease provides new insights into the pathways of CNS iron metabolism of direct relevance to a variety of nutritional and genetic disorders of childhood.

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BibTeXRIS

J D Gitlin. 1998. Aceruloplasminemia.. https://doi.org/10.1203/00006450-199809000-00001

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Ceruloplasmin↗

Ceruloplasmin metabolism and function.

Ceruloplasmin is a serum ferroxidase that contains greater than 95% of the copper found in plasma. This protein is a member of the multicopper oxidase family, an evolutionarily conserved group of proteins that utilize copper to couple substrate oxidation with the four-electron reduction of oxygen to water. Despite the need for copper in ceruloplasmin function, this protein plays no essential role in the transport or metabolism of this metal. Aceruloplasminemia is a neurodegenerative disease resulting from inherited loss-of-function mutations in the ceruloplasmin gene. Characterization of this disorder revealed a critical physiological role for ceruloplasmin in determining the rate of iron efflux from cells with mobilizable iron stores and has provided new insights into human iron metabolism and nutrition.

Ceruloplasmin↗