Liver disease predominates in a mouse model for mild human Zellweger spectrum disorder.
Zellweger spectrum disorders (ZSDs) are autosomal recessive diseases caused by defective peroxisome assembly. They constitute a clinical continuum from severe early lethal to relatively milder presentations in adulthood. Liver disease is a prevalent symptom in ZSD patients. The underlying pathogenesis for the liver disease, however, is not fully understood. We report a hypomorphic ZSD mouse model, which is homozygous for Pex1-c.2531G>A (p.G844D), the equivalent of the most common pathogenic variant found in ZSD, and which predominantly presents with liver disease. After introducing the Pex1-G844D allele by knock-in, we characterized homozygous Pex1-G844D mice for survival, biochemical parameters, including peroxisomal and mitochondrial functions, organ histology, and developmental parameters. The first 20 post-natal days (P20) were critical for survival of homozygous Pex1-G844D mice (~20% survival rate). Lethality was likely due to a combination of cholestatic liver problems, liver dysfunction and caloric deficit, probably as a consequence of defective bile acid biosynthesis. Survival beyond P20 was nearly 100%, but surviving mice showed a marked delay in growth. Surviving mice showed similar hepatic problems as described for mild ZSD patients, including hepatomegaly, bile duct proliferation, liver fibrosis and mitochondrial alterations. Biochemical analyses of various tissues showed the absence of functional peroxisomes accompanied with aberrant levels of peroxisomal metabolites predominantly in the liver, while other tissues were relatively spared. ur findings show that homozygous Pex1-G844D mice have a predominant liver disease phenotype, mimicking the hepatic pathology of ZSD patients, and thus constitute a good model to study pathogenesis and treatment of liver disease in ZSD patients.
['Berendse|Kevin|K|', 'Boek|Maxim|M|', 'Gijbels|Marion|M|', 'Van der Wel|Nicole N|NN|', 'Klouwer|Femke C|FC|', 'van den Bergh-Weerman|Marius A|MA|', 'Shinde|Abhijit Babaji|AB|', 'Ofman|Rob|R|', 'Poll-The|Bwee Tien|BT|', 'Houten|Sander M|SM|', 'Baes|Myriam|M|', 'Wanders|Ronald J A|RJA|', 'Waterham|Hans R|HR|']
D000074183:ATPases Associated with Diverse Cellular Activities D000483:Alleles D000818:Animals D004195:Disease Models, Animal D005260:Female D005347:Fibroblasts D006801:Humans D008099:Liver D008107:Liver Diseases D008297:Male D008565:Membrane Proteins D051379:Mice D008810:Mice, Inbred C57BL D018345:Mice, Knockout D008928:Mitochondria D020675:Peroxisomes D010641:Phenotype D015211:Zellweger Syndrome
Peroxisome Bile acid synthesis Cholestasis Metabolism Peroxisome biogenesis disorder Zellweger syndrome