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ABSTRACT: The aim of this study is to investigate the anticancer effect of aloe-emodin in two human liver cancer cell lines, Hep G2 and Hep 3B. We observed that aloe-emodin inhibited cell proliferation and induced apoptosis in both examined cell lines, but with different the antiproliferative mechanisms. In Hep G2 cells, aloe-emodin induced p53 expression and was accompanied by induction of p21 expression that was associated with a cell cycle arrest in G1 phase. In addition, aloe-emodin had a marked increase in Fas/APO1 receptor and Bax expression. In contrast, with p53-deficient Hep 3B cells, the inhibition of cell proliferation of aloe-emodin was mediated through a p21-dependent manner that did not cause cell cycle arrest or increase the level of Fas/APO1 receptor, but rather promoted aloe-emodin induced apoptosis by enhancing expression of Bax. These findings suggest that aloe-emodin may be useful in liver cancer prevention.
Life Sciences 10/2002; 71(16):1879-92. · 2.53 Impact Factor
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ABSTRACT: Prodelphinidin B-2 3-O-gallate, a proanthocyanidin gallate isolated from green tea leaf, was investigated for its anti-herpes simplex virus type 2 properties in vitro. Prodelphinidin B-2 3'-O-gallate exhibited antiviral activity with IC50 of 5.0 +/-1.0 microM and 1.6 +/-0.3 pM for XTT and plaque reduction (PRA) assays, respectively. Cytotoxicity assay had shown that prodelphinidin B-2 3'-O-gallate possessed cytotoxic effect toward Vero cell at concentration higher than its IC50. The 50% cytotoxic concentration for cell growth (CC50) was 33.3 +/- 3.7 microM. Thus, the selectivity index (SI) (ratio of IC50 to CC50) for XTT assay and PRA was 6.7 and 20.8, respectively. Prodelphinidin B-2 3'-O-gallate significantly reduced viral infectivity at concentrations 10 microM or more. Result of time-of-addition studies suggested that prodelphinidin B-2 3'-O-gallate affected the late stage of HSV-2 infection. In addition, it was also shown to inhibit the virus from attaching and penetrating into the cell. Thus, prodelphinidin B-2 3'-O-gallate was concluded to possess antiviral activity with mechanism of inhibiting viral attachment and penetration, and disturbing the late stage of viral infection.
Antiviral chemistry & chemotherapy 08/2002; 13(4):223-9.
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ABSTRACT: The antioxidant and antiviral activities of Euphorbia thymifolia L. (Euphorbiaceae) were investigated in this study. The results showed that all of the fractions (MeOH, CHCl(3), EtOAc, n-butanol and water) and pure compounds (3-O-galloyl-4,6-(S)-HHDP-D-glucose, rugosin B and 1,3,4,6-tetra-O-galloyl-K-beta-D-glucose)tested possessed antioxidant activities, with the exception of the organic aqueous fraction in the anti-lipid and anti-superoxide formation assays. The range of IC(50) of anti-lipid formation, anti-superoxide formation and free radical scavenging assays for all fractions and pure compounds were 2.81-7.63, 0.03-2.18 and 0.013-2.878 mg/ml, respectively. Electron spin resonance studies showed that water extract and pure compounds of E. thymifolia exhibited superoxide radical and hydroxyl radical scavenging activities. Besides antioxidant activities, 3-O-galloyl-4,6-(S)-HHDP-D-glucose and EtOAc fraction also showed anti-HSV-2 activity. Thus, E. thymifolia was concluded to possess antioxidant and anti-HSV-2 activities.
Journal of Biomedical Science 01/2002; 9(6 Pt 2):656-64. · 2.01 Impact Factor
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ABSTRACT: 1. The ethyl acetate (EtOAc) extract and 3-O-galloyl-4,6-(S)-hexahydroxydiphenoyl-d-glucose (3OG46HG) of Euphorbia thymifolia Linnea have been shown to exhibit anti-herpes simplex virus (HSV)-2 activity in vitro. In the present study, we investigated the mode of action of these two compounds in suppressing HSV-2 multiplication. 2. The results demonstrated that the EtOAc extract and 3OG46HG affected virus infectivity in a dose-dependent manner. The EtOAc extract significantly reduced virus infectivity at a concentration of 4.0 microg/mL, whereas 3OG46HG obviously diminished virus infectivity at concentration of a 0.5 microg/mL. The virucidal ability of the EtOAc extract was affected by the incubation period, but not by the incubation temperature. In the case of the action of 3OG46HG against HSV-2, the effects of incubation time and temperature were negligible. 3. In summary, the EtOAc extract and 3OG46HG of E. thymifolia are concluded to inhibit HSV-2 multiplication by reducing virus infectivity.
Clinical and Experimental Pharmacology and Physiology 32(5-6):346-9. · 1.85 Impact Factor
