Abstract
Aim:
To investigate the effects of wogonin (5,7-dihydroxy-8-methoxyflavone) extracted from Scutellaria baicalensis Georgi (S baicalensis) on lipotoxicity-induced apoptosis of vascular smooth muscle cells (VSMCs) and the underlying mechanisms.
Methods:
Cultured VSMCs were used. Apoptosis of VSMCs was induced by palmitate (0.75 mmol/L), and detected using TUNEL assay. The expression levels of protein and phosphorylated protein were measured using Western blot analysis.
Results:
Treatment of VSMCs with wogonin (10, 25 and 50 μmol/L) significantly attenuated the apoptosis and endoplasmic reticulum (ER) stress induced by palmitate in concentration- and time-dependent manners. Wogonin (50 μmol/L) decreased palmitate-induced reactive oxygen species (ROS) generation. The ER stress inhibitor 4-phenyl butyric acid (5 mmol/L) significantly decreased palmitate-induced apoptotic cells, and occluded the anti-apoptotic effect of wogonin (25 μmol/L). Wogonin (10, 25 and 50 μmol/L) significantly reduced the intracellular diacylglycerol (DAG) accumulation and expression levels of phosphorylated PKCs in palmitate-treated VSMCs.
Conclusion:
Our results suggest that wogonin inhibits lipotoxicity-induced apoptosis of VSMCs via suppressing the intracellular DAG accumulation and subsequent inhibition of PKC phosphorylation. Wogonin has therapeutic potential for the prevention and treatment of atherosclerosis.
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Acknowledgements
We would like to thank Levi FROKE and Michael FREITAG (University of South Dakota, USA) for editing the manuscript for English grammar.
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Liu, Ym., Wang, X., Nawaz, A. et al. Wogonin ameliorates lipotoxicity-induced apoptosis of cultured vascular smooth muscle cells via interfering with DAG-PKC pathway. Acta Pharmacol Sin 32, 1475–1482 (2011). https://doi.org/10.1038/aps.2011.120
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DOI: https://doi.org/10.1038/aps.2011.120
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