HDAC inhibition improves cardiopulmonary and mitochondrial function in a feline model with features of Heart Failure with Preserved Ejection Fraction

ABSTRACT: Heart Failure with preserved Ejection Fraction (HFpEF) is a major global health problem but there are no effective therapies. The aim of this study was to assess the effects of histone deacetylase (HDAC) inhibition on cardiopulmonary structure, function, and metabolism in a large mammalian (feline) pressure overload model with HFpEF features. Male domestic short hair cats (n=26, aged 2mo), underwent either a sham procedure (n=5) or aortic constriction (n=21) using a pre-shaped band, resulting in slow-progressive pressure overload during subsequent growth. Two-months post-banding, banded cats were treated daily with either 10mg/kg suberoylanilide hydroxamic acid (b+SAHA) (n=8), an FDA approved pan-HDAC inhibitor, or vehicle (b+veh) (n=8) for 2 months. Echocardiography at 4-months post-banding revealed that b+SAHA animals had a significant reduction in left ventricular hypertrophy (LVH) and LA size vs b+veh animals. Invasively measured left ventricular end-diastolic pressure (LVEDP) and mean pulmonary arterial pressure (mPAP) were significantly elevated in b+veh and significantly reduced by b+SAHA. SAHA speeded ex-vivo myofibril relaxation independent of LVH and this effect correlated with in-vivo indices of LV relaxation. Furthermore, SAHA preserved lung structure, improved lung compliance and oxygenation, reflected by a decrease in alveolar-capillary wall thickness, alveolar-arterial oxygen gradient (A-aDO2), and intrapulmonary shunt. SAHA also reduced perivascular fluid cuffs around extra-alveolar vessels, suggesting attenuated alveolar-capillary stress failure. Acetylation proteomics revealed that SAHA altered protein acetylation in cat hearts, including histones, many mitochondrial metabolic enzymes involved in electron transport chain, TCA cycle, malate aspartate shuttle and beta oxidation, as well as cytoskeletal proteins important for muscle function. These results suggest that acetylation defects in hypertrophic stress states can be reversed by HDAC inhibitors and may be useful to improve cardiac structure and function in HFpEF patients.

INSTRUMENT(S): maXis

ORGANISM(S): Felis Catus (cat) (felis Silvestris Catus)

TISSUE(S): Heart

SUBMITTER: Barbara Darnhofer  

LAB HEAD: Ruth Birner-Gruenberger

PROVIDER: PXD013663 | Pride | 2021-09-08

REPOSITORIES: Pride