Iron-induced oxidative damage and apoptosis in cerebellar granule cells: attenuation by tetramethylpyrazine and ferulic acid

• Published in: European journal of pharmacology Vol. 467; no. 1; pp. 41 - 47
• Main Authors: Zhang, Zhaohui, Wei, Taotao, Hou, Jingwu, Li, Gengshan, Yu, Shaozu, Xin, Wenjuan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 25.04.2003; Elsevier
• Subjects: Animals; Apoptosis; Apoptosis - drug effects; Biological and medical sciences; Caspase 3; Caspases - metabolism; Cells, Cultured; Cerebellar granule cell; Cerebellum - drug effects; Cerebellum - ultrastructure; Coumaric Acids - pharmacology; Cyclin-Dependent Kinase Inhibitor p21; Cyclins - metabolism; DNA Fragmentation - drug effects; Down-Regulation; Drugs, Chinese Herbal - pharmacology; Enzyme Activation; Fe ion; Ferulic acid; Gene Expression Regulation; Genes, p53 - drug effects; Iron - antagonists & inhibitors; Iron - toxicity; Lipid Peroxidation - drug effects; Medical sciences; Neuroprotective Agents - pharmacology; Oxidative Stress - drug effects; Pyrazines - pharmacology; Rats; Rats, Wistar; Tetramethylpyrazine; Cerebellar granule cell; Fe ion; Tetramethylpyrazine; Apoptosis; Ferulic acid
• ISSN: 0014-2999; 1879-0712
• DOI: 10.1016/S0014-2999(03)01597-8

Tetramethylpyrazine and ferulic acid are two active ingredients of a Chinese herbal medicine Ligusticum wallichi Franchat. In the present investigation, iron-induced oxidative neuronal damage and the protective effects of tetramethylpyrazine and ferulic acid against this induction were studied in primary cultures of rat cerebellar granule cells. When neurons were treated with 200 μM of FeSO 4 for 1 h, lipid peroxidation in neurons increased time dependently, as measured with the thiobarbituric acid assay. Thirty-six hours after iron treatment, the cell viability decreased to 43.6% and the percentage of apoptotic cells increased to 50.6%. Transmission electron microscopic examination showed a disrupted nuclear envelope and condensed chromatin in iron-treated neurons. Analysis of DNA extracted from iron-treated cells by agarose gel electrophoresis showed the typical “ladder pattern”, which indicated the formation of mono- and oligonucleosomes. After iron treatment, caspase 3 activity increased significantly, as measured in a fluoregenic assay. The results above suggested that iron treatment triggered oxidative stress and apoptosis in neurons. Western blot revealed that iron treatment up-regulated the apoptosis-related gene p53 as well as its effector gene p21 waf1/cip1. Pretreatment of the cells with 100 μM of tetramethylpyrazine or ferulic acid effectively decreased the activation of caspase 3 as well as the expression of p53 and p21 waf1/cip1, and attenuated iron-induced oxidative damage and apoptosis. The results suggest that tetramethylpyrazine and ferulic acid might be used as preventive agents against neuronal diseases associated with oxidative stress.