Apoptosis triggered by vitexin in U937 human leukemia cells via a mitochondrial signaling pathway.

Vitexin, a lignan compound, has been shown to exert apoptotic actions on human breast cancer cell lines and to have anti-inflammatory activities. Nevertheless, there is currently no study addressing the effects of vitexin on the induction of apoptosis in U937 human leukemia cells. The aim of this study was to determine the anticancer effects and molecular mechanisms of vitexin on U937 leukemia cells. We showed that vitexin can potently induce programmed cell death in U937 leukemia cell growth as well as morphological changes that were examined by MTT assay and phase contrast microscopy, respectively. The DNA content and the levels of mitochondrial membrane potential (∆Ψm) were determined by flow cytometric analysis. The cell cycle arrest-regulated and apoptosis-associated protein levels were measured by western blotting. Vitexin-triggered apoptosis was accompanied by a decrease of the level of ∆Ψm and the percentage of viability and provoked apoptosis in U937 cells. The downregulation of the protein level for Bcl-2 with the simultaneous upregulation of caspase-3 and -9 protein expression in U937 cells were observed after treatment with vitexin. Therefore, our data provide a potential mechanism for the chemopreventive activity of vitexin, and we suggest that vitexin may serve as a therapeutic agent for the treatment of human leukemia.

Anti-inflammatory effects of Scoparia dulcis L. and betulinic acid.

The aims of this study intended to investigate the anti-inflammatory activity of the 70% ethanol extract from Scoparia dulcis (SDE) and betulinic acid on λ-carrageenan-induced paw edema in mice. The anti-inflammatory mechanism of SDE and betulinic acid was examined by detecting the levels of cyclooxygenase-2 (COX-2), nitric oxide (NO), tumor necrosis factor (TNF-α), interleukin-1ß (IL-1ß) and malondialdehyde (MDA) in the edema paw tissue and the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GRd) in the liver. The betulinic acid content in SDE was detected by high performance liquid chromatography (HPLC). In the anti-inflammatory model, the results showed that SDE (0.5 and 1.0 g/kg) and betulinic acid (20 and 40 mg/kg) reduced the paw edema at 3, 4 and 5 h after λ-carrageenan administration. Moreover, SDE and betulinic acid affected the levels of COX-2, NO, TNF-α and IL1-ß in the λ-carrageenan-induced edema paws. The activities of SOD, GPx and GRd in the liver tissue were increased and the MDA levels in the edema paws were decreased. It is suggested that SDE and betulinic acid possessed anti-inflammatory activities and the anti-inflammatory mechanisms appear to be related to the reduction of the levels of COX-2, NO, TNF-α and IL1-ß in inflamed tissues, as well as the inhibition of MDA level via increasing the activities of SOD, GPx and GRd. The analytical result showed that the content of betulinic acid in SDE was 6.25 mg/g extract.

Hepatoprotective effect of Scoparia dulcis on carbon tetrachloride induced acute liver injury in mice.

This study aims to investigate the hepatoprotective activity and active constituents of the ethanol extract of Scoparia dulcis (SDE). The hepatoprotective effect of SDE (0.1, 0.5 and 1 g/kg) was evaluated on the carbon tetrachloride (CCl(4))-induced acute liver injury. The active constituents were detected by high performance liquid chromatography (HPLC). Mice pretreated orally with SDE (0.5 and 1.0 g/kg) and silymarin (200 mg/kg) for five consecutive days before the administering of a single dose of 0.2% CCl(4) (10 ml/kg of bw, ip) showed a significant inhibition of the increase of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Histological analyses also showed that SDE (0.5 and 1.0 g/kg) and silymarin reduced the extent of liver lesions induced by CCl(4), including vacuole formation, neutrophil infiltration and necrosis. Moreover, SDE decreased the malondialdehyde (MDA) level and elevated the content of reduced glutathione (GSH) in the liver as compared to those in the CCl(4) group. Furthermore, SDE (0.5 and 1.0 g/kg) enhanced the activities of anti-oxidative enzymes including superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GRd) and glutathione-S-transferase (GST). The quantities of active constituents in SDE were about 3.1 mg luteolin/g extract and 1.1 mg apigenin/g extract. The hepatoprotective mechanisms of SDE were likely associated to the decrease in MDA level and increase in GSH level by increasing the activities of antioxidant enzymes such as SOD, GPx, GRd and GST. These results demonstrated that SDE could alleviate CCl(4)-induced acute liver injury in mice.

Hepatoprotective effect of Phyllanthus in Taiwan on acute liver damage induced by carbon tetrachloride.

The effect of oral administration of Phyllanthus methanolic extracts (PME) (i.e. P. acidus, P. emblica, P. myrtifolius, P. multiflorus, P. amarus, P. debilis, P. embergeri, P. hookeri, P. tenellus, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria) or gallic acid (GA) on the progression of acute liver damage induced by CCl(4) in rats was examined by morphological and biochemical methods. P. acidus, P. urinaria L.s. urinaria, GA at a dose of 0.5 g/kg, and P. emblica, P. urinaria L.s. nudicarpus at a dose of 1.0 g/kg attenuated CCl(4)-induced increase in serum glutamate-oxalate-transaminase (GOT). P. acidus, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria, GA at a dose of 0.5 g/kg, and P. emblica, P. amarus, P. hookeri, P. tenellus at a dose of 1.0 g/kg attenuated CCl(4)-induced increase in serum glutamate-pyruvate-transaminase (GPT). Concurrently, P. acidus, P. multiflorus, P. embergeri, P. hookeri, P. tenellus and P. urinaria L.s. urinaria elevated the activity of liver reduced glutathione peroxidase (GSH-Px). Since the protective effects of P. acidus, P. emblica, P. myrtifolius, P. embergeri, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria and GA correlate with a reduction in liver infiltration and focal necrosis observed using histological methods, these data demonstrate that P. acidus and P. urinaria L.s. urinaria are hepatoprotective and antioxidant agents.