Journal of Molecular Neuroscience

, Volume 40, Issue 3, pp 311–320 | Cite as

Neuroprotective Effect of Baicalein on Hydrogen Peroxide-Mediated Oxidative Stress and Mitochondrial Dysfunction in PC12 Cells



Oxidative stress plays an important role in many neurodegenerative disorders. In this study, the effect of baicalein, a natural flavonoid isolated from the root of Scutellaria baicalensis G., on hydrogen peroxide (H2O2)-induced cytotoxicity in PC12 cells were investigated. Exposure of PC12 cells to 0.15 mM H2O2 for 20 min induced a significant decrease in cell viability accompanied by increased oxidative stress, mitochondrial dysfunction, downregulation of Bcl-2, upregulation of Bax, and cell apoptosis. Pretreatment of PC12 cells with baicalein inhibited H2O2-induced cell viability loss, intracellular reactive oxygen species generation, and lipid peroxidation in a dose-dependent manner. Meanwhile, baicalein potentially inhibited H2O2-induced cell apoptosis characterized with the DNA fragment. And the mitochondrial pathway involving the mitochondrial dysfunction associated with cell apoptosis including membrane potential loss, the release of cytochrome c, the downregulation of Bcl-2, upregulation of Bax induced by H2O2 were also abrogated in the presence of baicalein. Taken together, these results suggest that baicalein can block H2O2-induced apoptosis by prevention of oxidative stress as well as regulation of Bcl-2 family members and suppression of mitochondria dysfunction, which might be beneficial for the treatment of oxidative stress in aging and age-associated neurodegenerative diseases.


Baicalein H2O2 Oxidative stress PC12 cells ROS Apoptosis 



Pheochromocytoma cells




Dichlorofluorescin diacetate


Malonyl dialdehyde


3(4,5-Dimethylthiazol-2yl)2,5-diphenyl-2H-tetrazolium bromide


Phosphate-buffered saline


Reactive oxygen species


Lipid peroxidation


Relative fluorescence unit



We thank Dr. Lu Ling for her input and technical assistance. We also acknowledge the generous support of the Natural Science Foundation of Shandong Province, China (Grant No. Q2008C04).


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Copyright information

© Humana Press 2009

Authors and Affiliations

  1. 1.Laboratory of Fiber Materials and Modern Textile Growing Base for State Key LaboratoryQingdao UniversityQingdaoPeople’s Republic of China
  2. 2.Department of Pathophysiology, Qingdao Medical CollegeQingdao UniversityQingdaoPeople’s Republic of China
  3. 3.Department of Medicine, the Affiliated Hospital of Qingdao Medical CollegeQingdao UniversityQingdaoPeople’s Republic of China

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