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bioRxiv · 10.1101/457044

Accumulation of prelamin A drives inflammation in the heart with implications for treatment of inherited and acquired cardiomyopathies

Abstract

Cardiomyopathies are complex heart muscle diseases that can be inherited e.g. dilated cardiomyopathy resulting from LMNA gene mutations, or acquired, e.g. cardiomyopathy associated with HIV. In both cases the lamin A precursor, prelamin A, may play a central role: mutations in LMNA and certain HIV protease inhibitors acting via the enzyme ZMPSTE24 both inhibit prelamin A processing. Firstly, we show that myocardial prelamin A accumulation occurs in both these cardiomyopathies in patients. Secondly, we developed a novel mouse model of cardiac specific prelamin A accumulation which mimicked tissue and molecular features of HIV associated cardiomyopathy, including inflammation. These findings: (1) confirm a central pathological role of prelamin A common to genetic and acquired cardiomyopathies; (2) have implications for the management of HIV patients with cardiac disease in whom protease inhibitors with low/no binding to ZMPSTE24 may be preferred; and (3) suggest that targeting inflammation may be a useful treatment strategy for some forms of inherited cardiomyopathy.

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BibTeXRIS

Brayson, D., Frustaci, A., Verardo, R., Chimenti, C., Russo, M. A., Hayward, R., Ahmad, S. M., Vizcay-Barrena, G., Protti, A., Zammit, P. S., dos Remedios, C. G., Ehler, E., Shah, A. M., Shanahan, C. M.. 2018-11-04. Accumulation of prelamin A drives inflammation in the heart with implications for treatment of inherited and acquired cardiomyopathies. https://doi.org/10.1101/457044

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