rhodanine and Liver-Cirrhosis

This preliminary study summarizes the genotypes of 42 Labrador Retrievers and Labrador Retriever-Golden Retriever crosses and phenotypes a subset of ten of these dogs that are homozygous mutant, heterozygous, or homozygous normal for mutations in the ATP7A and ATP7B genes that have been associated with the development of copper toxicosis in Labrador Retrievers. The purpose of this study is to evaluate whether there is a correlation between ATP7A and ATP7B genotypes and clinical evidence of hepatic pathology in young, asymptomatic Labrador Retrievers. We evaluated serum ALT levels, hepatic copper concentrations, and hepatic histopathology from ten offspring where both parents had a least one copy of the ATP7B mutation. Five were homozygous mutant, four were heterozygous, and one was homozygous normal for comparison. None had increased serum ALT activity. All dogs homozygous for the ATP7B mutation had elevated hepatic copper concentrations compared to dogs heterozygous for the ATP7B mutation regardless of sex or presence of an ATP7A mutation with the mean hepatic copper concentration being 1464 ppm (reference range 100-330 ppm). Mean hepatic copper concentration in homozygous normal and heterozygous dogs was 328 ppm. In this preliminary analysis, we found that dogs that carry two copies of the ATP7B mutation have abnormally elevated hepatic copper levels despite having normal serum ALT activity. Our findings support the hypothesis that the ATP7B DNA test can predict defects in hepatic copper metabolism. Veterinarians can test for the ATP7B gene mutation to identify Labrador Retrievers at risk for copper toxicosis so that they can take steps to prevent development of copper-associated chronic hepatitis in their patients.

Topics: Alanine Transaminase; Animals; Copper; Copper-Transporting ATPases; Dog Diseases; Dogs; Female; Genetic Predisposition to Disease; Genotype; Hepatolenticular Degeneration; Humans; Liver Cirrhosis; Male; Metal Metabolism, Inborn Errors; Rhodanine

The incidental finding of orcein positive granules, indicating copper associated protein, in alpha-1-antitrypsin (AAT) positive liver biopsies stimulated a histochemical search for evidence of copper and copper-binding protein in a series of 46 liver biopsies with histological evidence of AAT accumulation. Hepatic accumulation copper and copper-binding protein occurred in all 19 cirrhotics (100%) and in 14 out of 27 non-cirrhotic livers (51.85%). The overall percentage was 71.73%. AAT and copper deposits coexisted in the same periportal hepatocytes. AAT globules showed positive reactivity both to rhodanine and orcein stains. The severity of chronic liver damage correlated with increasing amounts of copper deposition. It is suggested that in AAT storage, not only is the metabolism of this substance disturbed, but also that of proteins involved in copper metabolism and excretion, resulting in copper accumulation within hepatocytes.

Topics: Adolescent; Adult; Aged; alpha 1-Antitrypsin; Carrier Proteins; Cholestasis, Intrahepatic; Copper; Cytoplasmic Granules; Female; Humans; Liver; Liver Cirrhosis; Liver Diseases; Male; Middle Aged; Rhodanine

Morphological, histochemical, and chemical study of three necropsy specimens of liver in the terminal stage of Indian Childhood Cirrhosis revealed a strikingly high copper content. it is proposed that excess accumulation of copper in the cytoplasm of hepatocytes disturbs the microtubular system, causing hydropic swelling and the formation of Mallory's hyalin. Copper and copper-binding protein showed topographical association with Mallory's hyalin. Diffuse cytoplasmic staining and the lysosomal copper distribution also suggested that copper had a cytotoxic effect. The pattern of copper distribution in Indian Childhood Cirrhosis differs from that in Wilson's disease and in prolonged cholestasis with excessive hepatic copper deposition, indicating a different mechanism of the copper accumulation.

Topics: Child, Preschool; Copper; Cytoplasm; Cytoplasmic Granules; Histocytochemistry; Humans; India; Infant; Liver; Liver Cirrhosis; Lysosomes; Male; Microscopy, Electron; Protein Binding; Rhodanine; Staining and Labeling