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Angiotensin II (Ang II) stimulates endothelin (ET-1) transcription, which contributes to cardiac hypertrophy and fibrosis. We have previously reported that myocardin related transcription factor A (MRTF-A) is indispensable for ET-1 transcription in vascular endothelial cells under hypoxic conditions, indicating that MRTF-A might mediate Ang II-induced pathological hypertrophy. Here we report that Ang II augmented the expression of MRTF-A in cultured endothelial cells and in the lungs of mice with cardiac hypertrophy. Over-expression of MRTF-A enhanced, whereas depletion of MRTF-A attenuated, transcriptional activation of ET-1 gene by Ang II. MRTF-A deficiency ameliorated Ang II induced cardiac hypertrophy and fibrosis in mice paralleling diminished synthesis and release of ET-1. Mechanistically, MRTF-A was recruited to the ET-1 promoter by c-Jun/c-Fos (AP-1) in response to Ang II treatment. Once bound, MRTF-A altered the chromatin structure by modulating histone acetylation and H3K4 methylation on the ET-1 promoter. More importantly, mice with endothelial-specific MRTF-A silencing by lentiviral particles phenocopied mice with systemic MRTF-A deletion in terms of Ang II-induced pathological hypertrophy. In conclusion, we data have unveiled a MRTF-A-containing complex that links ET-1 transactivation in endothelial cells to cardiac hypertrophy and fibrosis by Ang II. [ABSTRACT FROM AUTHOR]

The interaction between rice protein isolate (RPI) and ferulic acid (FA) was systematically investigated. The results showed that fluorescence intensity of the RPI decreased gradually upon increasing the concentration of ferulic acid, and the maximum emission shifted from 352.0 to 359.2 nm. It was proposed that a static quenching of RPI-FA complex occurred, due to the hydrophobic interactions. Moreover, CD spectra and FT-IR spectroscopy data suggested that the concentration of β-turn and α-helix decreased while those of random coil and β-sheet increased in RPI-FA complex. The decrease of intensity of the amide I band and amide II band in the RPI-FA complex implied a significant reduction of protein α-helical structure and the presence of non-polar hydrophobic interactions. In addition, SDS-PAGE results demonstrated that ferulic acid reacted with glutelin acidic subunits (34–37 KDa) as well as globulin (26 KDa), and ferulic acid might bind with aromatic amino acid residues of RPI. Furthermore, the RPI-FA complex exhibited high DPPH• scavenging ability, ABTS+• scavenging ability and ORAC value. Finally, emulsion stabilized by RPI-FA complex could decrease the concentration of hydroperoxide, TBARS, and hexanal, thereby effectively restraining fat oxidation degradation. Image 1 • Rice protein isolate and ferulic acid were interacted by hydrophobic interactions. • Ferulic acid reacted with gluten acid subunits and globulin of RPI. • RPI-FA complex could improve the oxidative stability of corn oil in emulsion. [ABSTRACT FROM AUTHOR]