The present study was undertaken to investigate the effects of Moutan Cortex Radicis extracts and paeonol, a major component, on rabbit platelet aggregation and thromboxane (TX) B₂ formation. Moutan Cortex Radicis methanol and butanol layers (100 μg/mL) showed the weak inhibitions, and water layer (100 μg/ mL) had no effect on the collagen-induced platelet aggregation. Whereas, hexane and EtOAc layers potently inhibited the collagen (3 μg/mL)-induced platelet aggregation with the IC_(50) values of 10.9±1.0 and 31.5±0.8 μg/mL, respectively. Paeonol isolated from the hexane-acetone layer specifically inhibited the collagen-induced platelet aggregation with the IC_(50) value of 113.1 ± 0.9 μM, whereas it had little effects on the other agonists such as AA-, thrombin-, A23187- and thapsigargin-induced platelet aggregations. Paeonol also potently inhibited the collagen-induced TXB₂ formation in rabbit platelet in a concentration-dependent manner. These results suggest that paeonol may inhibit rabbit platelet aggregation by interfering with an essential step in collagen-induced platelet activation and TXA₂ formation. Paeonol may be a promising candidate for an antiplatelet agent.

Previous work demonstrated that an ethanol extract (HS0608) of a mixture of three medicinal plants of Curcuma longae radix, Phellinus linteus, and Scutellariae radix markedly inhibits Aβ (25-35)-induced neurotoxicity. The present study was performed to further verify the neuroprotective effect of HS0608 on oxidative and ischemic cerebral injury using cultured rat cortical neurons and rats. Exposure of cultured cortical neurons to 100 μM hydrogen peroxide (H2O2) induced neuronal apoptotic death. At 10-100μg/ml, HS0608 inhibited neuronal death, elevation of intracellular calcium concentration ([Ca2+]i), and generation of reactive oxygen species (ROS) induced by H2O2 in primary cultures of rat cortical neurons. In vivo, HS0608 prevented cerebral ischemic injury induced by 2-h middle cerebral artery occlusion (MCAO) and 24-h reperfusion. The ischemic infarct and edema were significantly reduced in rats that received HS0608 (200 mg/kg). These results suggest that the anti-oxidative properties of HS0608 may be responsible for its neuroprotective effect against focal cerebral ischemic injury and that HS0608 may have a therapeutic role in neurodegenerative diseases such as stroke.

Vitis amurensis (VA; Vitaceae) has long been used in oriental herbal medicine. It has been reported that roots and seeds of VA have anti-inflammatory and antioxidant effects. In the present study, the protective effect of ethanol extract from stems and leaves of VA on hydrogen peroxide (H2O2) (100 μm)-induced neuronal cell damage was examined in primary cultured rat cortical neurons. VA (10-100 μg/ml) concentration-dependently inhibited H2O2-induced apoptotic neuronal cell death measured by 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. VA inhibited H2O2-induced elevation of intracellular Ca2+ concentration ([Ca2+]i) and generation of reactive oxygen species (ROS), which were measured by fluorescent dyes. Pretreatment of VA also prevented glutamate release into medium induced by 100 μm H2O2, which was measured by HPLC. These results suggest that VA showed a neuroprotective effect on H2O2-induced neuronal cell death by interfering with H2O2-induced elevation of [Ca2+]i, glutamate release, and ROS generation. This has a significant meaning of finding a new pharmacological activity of stems and leaves of VA in the CNS.

Dried leaves from Cedrela sinensis A. Juss. (CS), have been observed to possess various pharmacological activity and contain various antioxidant constituents. The protective effect of ethanol extract of CS on hydrogen peroxide (H2O2)-induced neurotoxicity was examined using primary cultured rat cortical neurons in the present study. Exposure of cultured neurons to 100 μM H2O2 caused a significant neuronal death as assessed by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. The addition of CS, over a concentration range of 10 to 50μg/ml, concentration-dependently prevented the H2O2-induced neuronal apoptotic death. CS (50μg/ml) significantly inhibited H2O2-induced elevation of the cytosolic Ca2+ concentration ([Ca2+]c), which was measured by a fluorescent dye, Fluo-4 AM. CS (30 and 50μg/ml) inhibited glutamate release and generation of reactive oxygen species (ROS) induced by 100μM H2O2. These results suggest that CS may mitigate the H2O2-induced neurotoxiciy by interfering with the increase of [Ca2+]c, and then inhibiting glutamate release and generation of ROS in cultured neurons.

Gardeniae Fructus (Gardenia jasmmoides Ellis) is widely used as a natural food colorant and as a traditional medicine for the treatment of hepatic and inflammatory diseases. The quality evaluation of Gardeniae Fructus was carried out by HPLC using geniposide as a marker. The geniposide was isolated from commercial Gardeniae Fructus on ODS column using a mixed solvent of acetonitrile-water (v/v 9:91) as mobile phase and a detection wavelength 240 mm. The content of geniposides in twenty different samples was in a range of 1.20% to 7.17% of total tissues and the average was 4.97%.

21 종의 생약 추출물을 선정하여 5 μg/ml의 농도에서 SK-MEL-28 cell 에 대한 세포독성을 조사한 결과 목단피의 메탄올 추출물이 74.3%의 성장율을 보였다. 활성 물질을 찾기 위하여 목단피로부터 silica gel column chromatography를 실시하여 hexane 분획과 EtOAc 분획에서 충 5개의 화합물을 분리하였고 mp, UV, IR, 1H-NMR, 13C-NMR 등 각종 물리, 화학적 data로부터 그 구조를 paeonol (1), benzoylpaeoniflorin (2), benzoic acid (3), 2,5-dihydroxy-4-methoxy-acetophenone (4), paeoniflorin (5)으로 동정하였다. 분리한 물질을 human 피부 암세포인 SK-MEL-28 세포주에 대하여 10 μg/ml의 농도에서 SRB방법으로 세포독성을 측정한 결과 compound 4가 ED50 값이 5.92 μg/ml로 가장 좋은 세포독성을 나타내었다. 이결과는 compound 4가 SK-MEL-28 melanoma 세포주에 대한 새로운 항암 후보 물질임을 제시한다.