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Desmoglein 2 mutant mice develop cardiac fibrosis and dilation.

ABSTRACT: Desmosomes are cell-cell adhesion sites and part of the intercalated discs, which couple adjacent cardiomyocytes. The connection is formed by the extracellular domains of desmosomal cadherins that are also linked to the cytoskeleton on the cytoplasmic side. To examine the contribution of the desmosomal cadherin desmoglein 2 to cardiomyocyte adhesion and cardiac function, mutant mice were prepared lacking a part of the extracellular adhesive domain of desmoglein 2. Most live born mutant mice presented normal overall cardiac morphology at 2 weeks. Some animals, however, displayed extensive fibrotic lesions. Later on, mutants developed ventricular dilation leading to cardiac insufficiency and eventually premature death. Upon histological examination, cardiomyocyte death by calcifying necrosis and replacement by fibrous tissue were observed. Fibrotic lesions were highly proliferative in 2-week-old mutants, whereas the fibrotic lesions of older mutants showed little proliferation indicating the completion of local muscle replacement by scar tissue. Disease progression correlated with increased mRNA expression of c-myc, ANF, BNF, CTGF and GDF15, which are markers for cardiac stress, remodeling and heart failure. Taken together, the desmoglein 2-mutant mice display features of dilative cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy, an inherited human heart disease with pronounced fibrosis and ventricular arrhythmias that has been linked to mutations in desmosomal proteins including desmoglein 2.

SUBMITTER: Krusche CA

PROVIDER: S-EPMC3105238 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Desmoglein 2 mutant mice develop cardiac fibrosis and dilation.

Krusche Claudia A CA Holthöfer Bastian B Hofe Valérie V van de Sandt Annette M AM Eshkind Leonid L Bockamp Ernesto E Merx Marc W MW Kant Sebastian S Windoffer Reinhard R Leube Rudolf E RE

Basic research in cardiology 20110401 4

Desmosomes are cell-cell adhesion sites and part of the intercalated discs, which couple adjacent cardiomyocytes. The connection is formed by the extracellular domains of desmosomal cadherins that are also linked to the cytoskeleton on the cytoplasmic side. To examine the contribution of the desmosomal cadherin desmoglein 2 to cardiomyocyte adhesion and cardiac function, mutant mice were prepared lacking a part of the extracellular adhesive domain of desmoglein 2. Most live born mutant mice pres ...[more]

PMID: 21455723

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Desmoglein 2 mutant mice develop cardiac fibrosis and dilation.

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Desmoglein 2 mutant mice develop cardiac fibrosis and dilation.

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