Novel neuroprotective effects of the aqueous extracts from Verbena officinalis Linn.
Verbena officinialis Linn. (Verbenaceae) is a perennial plant which has been used as herbal medicine or health supplement in both Western and Eastern countries for centuries. It has been used to treat acute dysentery, enteritis, amenorrhea and depression. In view of its wide array of biological effects, we hypothesized that V. officinalis can exert cytoprotective effects on cells of the central nervous system. Pre-treatment of aqueous extracts of V. officinalis significantly attenuated the toxicity of beta-amyloid (Abeta) peptide and reducing agent dithiothreitol in primary cultures of cortical neurons. As extracellular accumulation of Abeta peptide is an important cytotoxic factor involved in Alzheimer's disease (AD), we have further explored its neuroprotective effect against Abeta. Treatment of V. officinalis attenuated Abeta-triggered DEVD- and VDVAD-cleavage activities in a dose-dependent manner. Further studies elucidated that phosphorylation of both interferon-inducing protein kinase (PKR) and c-Jun N-terminal kinase (JNK) was attenuated in Abeta-treated neurons. Taken together, we have proved our hypothesis by showing the novel neuroprotective effects of V. officinalis. As V. officinalis has long been used for many years to be a folk medicine, our study may provide a lead for its potential to be a neuroprotective agent against neuronal loss in AD.
Lai
Sau-Wan
SW
Laboratory of Neurodegenerative Diseases, Department of Anatomy, Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong.
Yu
Man-Shan
MS
Yuen
Wai-Hung
WH
Chang
Raymond Chuen-Chung
RC
D016229:Amyloid beta-Peptides / Q000633:toxicity; D000818:Animals; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D003634:DDT / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004622:Embryo, Mammalian; D007211:Indoles; D007372:Interferons / Q000494:pharmacology; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000187:drug effects*; D018696:Neuroprotective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010446:Peptide Fragments / Q000633:toxicity; D010766:Phosphorylation / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D011494:Protein Kinases / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D032412:Verbena / Q000737:chemistry*
D016229:Amyloid beta-Peptides; D007211:Indoles; D018696:Neuroprotective Agents; D010446:Peptide Fragments; D010936:Plant Extracts; C075222:amyloid beta-protein (1-42); C074636:amyloid beta-protein (25-35); C007293:DAPI; D007372:Interferons; D003634:DDT; D011494:Protein Kinases; D048670:MAP Kinase Kinase 4; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases