earticle

영어

Cerebral ischemia results from cerebrovascular occlusion, which leads to neuronal cell death and eventually causes neurological disorders. Cordyceps is a known to have variable actions, such as increasing sexual drive, improving renal function, and exerting anti-cancer effect. We investigated the effect of aqueous extract of Guem Chung Choon apoptosis in the hippocampus after transient global ischemia using gerbils. Guem Chung Cho is an artificially cultivated Cordyceps, and was supplied from GCordy (Seoul, Korea). Aqueous extract of Guem Chung Cho (50 g) was made by rotary evaporate, and resulting powder 11.5 g was obtained (yield 23 %). Transient global ischemia was induced by ligation of both common carotid arteries for 7 min. Aqueous extract of Guem Chung Cho was administrated orally at 3 respective doses (0.001, 0.01, and 0.1 mg/kg) once a day for 14 consecutive days, beginning 1 day after surgery. Short-term memory was assessed by a step-down avoidance test. Histological study was performed with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and immunohistochemistry for caspase-3 and 5-bromo-2’-deoxyuridine (BrdU). Western blot for Bcl-2, Bax, brain-derived neurotrophic factor (BDNF), and tyrosine kinase B (TrkB) was conducted. The results revealed that induction of cerebral ischemia impaired short-term memory with increased DNA fragmentation and caspase-3 expression in the hippocampal dentate gyrus. Induction of cerebral ischemia also enhanced expression of pro-apoptotic factor Bax protein and suppressed expression of anti-apoptotic factor Bcl-2 protein in the hippocampus. In addition, cerebral ischemic insult excessively increased cell proliferation in the hippocampal dentate gyrus, whereas, decreased the expressions of BDNF and TrkB in the hippocampus. Guem Chung Cho treatment ameliorated cerebral ischemia-induced impairment of short-term memory. Guem Chung Cho treatment suppressed apoptosis and cell proliferation and enhanced expressions of BDNF and TrkB. These effect of Guem Chung Cho appeared most potently at lowest dosage used in this study, 0.001 mg/kg. We showed that Guem Chung Cho may overcome ischemia-induced apoptotic neuronal cell death, thus facilitates recovery following ischemic cerebral injury. This study was supported by GCordy company.