Inhibition of Astragalus polysaccharide in lipopolysccharide-induced cardiomyocyte hypertrophy in rats through the TLR4/NF-κB signal transduction

Aim To explore the mechanism of Astragalus polysaccharide(APS) affecting lipopolysaccharide(LPS)-induced cardiac myocytes hypertrophy of rats from the aspect of TLR4-NF-κB signal transduction pathway.Methods The hypertrophic primary cardiac cells of neuonatal rats were induced by 1 mg·L-1 LPS,and the effect of different concentrations of APS and BAY11-7082(IκBα phosphorylation inhibitor) on cardiac hypertrophy was observed.The cardiomyocyte volume was measured by computer photograph analysis system and the total protein content was assayed by the method of Bradford;the expression of TLR4,IκBα and TNF-α were determined by RT-PCR,Western blot and ELISA,respectively.Results APS and BYA11-7082 could inhibit the LPS-induced cardiac hypertrophy by reducing the cardiomyocyte protein content and volume;APS could abolish the inflammatory response induced by LPS in a dose-dependent manner,which was partially via attenuating IκBα and TNF-α signaling pathway.Conclusion APS has a protective effect on LPS-induced cardiac hypertrophy,which is partially via attenuating inflammatory through TLR4/NF-κB signaling pathway.