Inhibition of lncRNA Neat1 by catalpol via suppressing transcriptional activity of NF-κB attenuates cardiomyocyte apoptosis

Oxidative stress is considered as a major pathogenesis in myocardial damage; however, effective therapies are limited so far. The present study aimed to investigate the in vitro antioxidative mechanism of Catalpol in cardiomyocytes. The results indicated that Catalpol attenuated high glucose (HG)-induced apoptosis in mouse cardiomyocytes via significantly downregulating long noncoding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (Neat1) expression. Furthermore, Catalpol downregulated Neat1 expression and attenuated apoptosis by inhibiting production of intracellular reactive oxygen species (ROS) in HG-treated cardiomyocytes. Moreover, Catalpol also suppressed HG-induced degradation of I kappa B alpha and the nuclear localization of nulear factor-kappa B (NF-kappa B) by decreasing the intracellular ROS levels. Additionally, chromatin immunoprecipitation (ChIP) and dual-luciferase activity assays validated that NF-kappa B bound to Neat1 promoter to activate Neat1 expression. In summary, these results implied that Catalpol protected mouse cardiomyocytes against oxidative injury at least partly through ROS-NF-kappa B-Neat1 axis.