Sanguisorbae radix (SR) from Sanguisorba officinalis L. (Losaceae) is widely used in Korea and China due to its various pharmacological activity. The present study aims to investigate the effect of the methanol extract of SR on amyloid β Protein(25-35) (Aβ (25-35)), a synthetic 25-35 amyloid peptide, -induced neurotoxicity using cultured rat cortical neurons. SR, over a concentration range of 10-50 μg/ml, inhibited the Aβ (25-35) (10 μM)-induced neuronal cell death, as assessed by a 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and the number of apoptotic nuclei, evidenced by Hoechst 33342 staining. Pretreatment of SR (50 μg/ml) inhibited 10 μM Aβ (25-35)-induced elevation of cytosolic calcium concentration ([Ca2+]c), which was measured by a fluorescent dye, fluo-4 AM. SR (10 and 50 μg/ml) inhibited glutamate release into medium induced by 10 μM Aβ(25-35), which was measured by HPLC, and generation of reactive oxygen species. These results suggest that SR prevents Aβ (25-35)-induced neuronal cell damage in vitro.

Caulis Bambusae in Taenia is widely used in Korea and China due to its various pharmacological activity. The present study aims to investigate the effect of the methanol extract of Caulis Bambusae in Taenia (CB) from Phyllostachys nigra Munro var. henonis Stapf (Gramineae) on amyloid β protein (25-35) (Aβ (25-35)), a synthetic 25-35 amyloid peptide, -induced neurotoxicity using cultured rat cortical neurons. CB, over a concentration range of 10-50μg/μl, inhibited the Aβ (25-35) (10 μM)-induced neuronal cell death, as assessed by a 3-[4,5-dimethyIthiazole-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and the number of apoptotic nuclei, evidenced by Hoechst 33342 staining. CB (50 μg/μl) inhibited glutamate release into medium induced by 10 μM Aβ, (25-35) which was measured by HPLC. Pretreatment of CB (50 μg/μl) inhibited 10μM Aβ (25-35)-induced elevation of cytosolic calcium concentration ([Ca2+]c), which was measured by a fluorescent dye, fluo-4 AM, and generation of reactive oxygen species. These results suggest that CB prevents Aβ (25-35)-induced neuronal ell damage in vitro.

Polygalae Radix (PR) from Polygala tenuifolia. (Polygalaceae) is traditionally used in China and Korea, since this herb has a sedative, antiinflammatory, and antibacterial agent. To extend pharmacological actions of PR in the CNS on the basis of its CNS inhibitory effect, the present study examined whether PR has the neuroprotective action against kainic acid (KA) -induced cell death in primarily cultured rat cerebellar granule neurons. PR, over a concentration range of 0.05 to 5μg/ml inhibited KA (500 μM)-induced neuronal cell death, which was measured by a trypan blue exclusion test and a 3-[4,5-dimethylthiazol-2-y1]-2,5-diphenyl-tetrazolium bromide (MTT) assay. PR (0.5μg/ml) inhibited glutamate release into medium induced by KA (500 μM), which was measured by HPLC. Pretreatment of PR (0.5μg/ml) inhibited KA (500 μM)-induced elevation of cytosolic calcium concentration ([Ca2+]c) which was measured by a fluorescent dye, Fura 2-AM, and generation of reactive oxygen species (ROS). These results suggest that PR prevents KA-induced neuronal cell damage in vitro.