Palmatine attenuates isoproterenol-induced pathological hypertrophy via selectively inhibiting HDAC2 in rats.

This study aimed to exploit the potential therapeutic value of palmatine in treatment of cardiac hypertrophy and the underlying molecular mechanism. Rat hypertrophy model was established by intraperitoneal isoproterenol (ISO) injection. The hypertrophy was evaluated with cardiac hypertrophic parameters, hemodynamic parameters, lipid profile, and non-specific cardiac markers. The animals were intraperitoneally administrated with either palmatine or vehicle. The relative expressions of ANP, BNP, HDAC2, HDAC5, KLF4, and INPP5F transcripts were determined by real-time polymerase chain reaction (PCR). The relative protein levels of HDAC2, HDAC5, KLF4, and INPP5F were analyzed by immunoblotting. Palmatine treatment significantly attenuated ISO-induced hypertrophy in rats and elicited remarkable repressions in ANP, BNP, and HDAC2 transcriptions but not HDAC5. The downstream effector genes KLF4 and INPP5F were greatly restored in a dose-dependent manner in response to palmatine treatment. Our data demonstrated that palmatine possessed promising therapeutic potential against hypertrophy, which was mediated by modulation of HDAC2-KLF4/INPP5F pathway.