Adrenergic receptor blockade-induced regression of pressure-overload cardiac hypertrophy is associated with inhibition of the calcineurin/NFAT3/GATA4 pathway

Abstract

Calcineurin and its downstream effectors nuclear factor of activated T-cells 3 (NFAT3) and zinc finger-containing transcription factor (GATA4) have been implicated in the development of cardiac hypertrophy. The aims of the present study were to investigate alterations in the calcineurin/NFAT3/GATA4 pathway in pressure-overload hypertrophy, and to determine whether adrenergic receptor blockade affects this signaling pathway. In aorta-banded rats compared with sham-operated rats, a significant increase in the phosphorylation levels of calcineurin and GATA4 was observed (both p<0.05), while the NFAT3 phosphorylation level was markedly decreased (p<0.05). Oral administration of either the non-selective β blocker/α-1 blocker carvedilol or the selective β-1 blocker metoprolol, but not the selective α-1 blocker terazosin, significantly suppressed the activated calcineurin/NFAT3/GATA4 pathway (all p<0.05) in addition to inducing a regression of cardiac hypertrophy. Pressure overload-induced up-regulation of c-myc was markedly attenuated by treatment with either carvedilol or metoprolol (both p<0.05). The present findings may expand our understanding of the correlation between sympathetic activity and the calcineurin/NFAT3/GATA4 pathway, and highlight these signal transducers as effective targets in the management of pressure overload-induced cardiac hypertrophy.