Shu-Jing Wu

Tocotrienol-rich fraction of palm oil exhibits anti-inflammatory property by suppressing the expression of inflammatory mediators in human monocytic cells

Tocotrienol-rich fraction (TRF) of palm oil has been shown to possess potent antioxidant, anticancer, and cholesterol lowering activities. In this study, our aim was to examine the effects of TRF on LPS-induced inflammatory response through measuring the production of inflammatory mediators, namely nitric oxide (NO), prostaglandin E(2) (PGE(2)), inducible nitric oxide synthase (iNOS), cytokines (TNF-alpha, IL-4, and IL-8), cyclooxygenase-1 and -2 (COX-1 and COX-2), and nuclear factor-kappaB (NF-kappaB) in human monocytic (THP-1) cells. At concentrations 0.5-5.0 microg/mL, TRF dose-dependently protected against LPS-induced cell death. At same concentrations, TRF also showed potent anti-inflammatory activity as demonstrated by a dose-dependent inhibition of LPS (1 microg/mL)-induced release of NO and PGE(2), and a significant decrease in the transcription of proinflammatory cytokines. TRF at 1.0 microg/mL significantly blocked the LPS induction of iNOS and COX-2 expression, but not COX-1. This anti-inflammatory activity was further supported by the inhibition of NF-kappaB expression. These results conclude that TRF possesses potent anti-inflammatory activity, and its mechanism of action could be through the inhibition of iNOS and COX-2 production, as well as NF-kappaB expression.

Antioxidant, antioedema and analgesic activities of Andrographis paniculata extracts and their active constituent andrographolide

Andrographis paniculata (AP), a popular ingredient of Oriental folk medicine, is commonly used for treating infection, inflammation, fever and diarrhoea. In this study, extracts prepared from cultivated AP and their active constituent andrographolide were evaluated for antioxidant, antioedema and analgesic activities. The results showed that the aqueous AP extract (AP‐H2O) exhibited a greater antioxidant activity than the ethanol AP extract (AP‐EtOH) in all model systems tested. At a concentration of 50 µg/mL, the free radical scavenging, xanthine oxidase inhibition and antilipid peroxidation activities for AP‐H2O were 66.8%, 57.3% and 65.3%, respectively, and for AP‐EtOH were 57.8%, 52.6% and 34.2%, respectively. At a dosage of 100 mg/kg, AP‐H2O and andrographolide, but not AP‐EtOH, showed antioedema and analgesic activities. In phytochemical analysis, AP‐H2O showed a higher concentration of total flavanoid but a lower phenol content than AP‐EtOH. In conclusion, AP‐H2O was more potent than AP‐EtOH in antioxidant activities. Furthermore, compared with andrographolide, AP‐H2O as an extract also appears to possess potent antioedema and analgesic activities. Copyright

Decreased expression of thrombomodulin is correlated with tumor cell invasiveness and poor prognosis in nonsmall cell lung cancer

Thrombomodulin (TM) plays a role in coagulation, inflammation, and cell adhesion. Reduction of TM expression plays an important role in the tumor metastatic process; however, insufficient information is available regarding the expression of TM in nonsmall cell lung cancer (NSCLC). Sixty NSCLC patients who underwent surgery were reviewed for TM expression and multiple variables were assessed by univariate and multivariate analyses. The expression level of TM and its metastatic ability were examined in vitro using the human NSCLC A549 cell line. TM expression in NSCLC was significantly correlated with survival; the 5‐yr survival rates of patients with high and low TM expression were 23% and 18% (P < 0.01), respectively. Distribution of TM was detected predominantly in the normal lung tissue compared with lung cancer tissue. Western blot analysis showed, on average, decreased expression levels of TM protein in the lung cancer tissues of patients with NSCLC. An in vitro study also showed that overexpression of TM can inhibit the invasiveness and migration ability of the A549 cell line, whereas silencing of TM significantly enhanced these processes. This inhibition of cellular migration by overexpression of TM was significantly prevented by the selective inhibitors of PI3K and Akt, but not by MAPK inhibitors. This study demonstrates that a decrease in TM expression may be an indicator in the prognosis of NSCLC patients and provides new insights into the molecular mechanisms of TM in the metastasis of NSCLC.

Supercritical carbon dioxide extract of Physalis peruviana induced cell cycle arrest and apoptosis in human lung cancer H661 cells.

Physalis peruviana L. (PP) is a popular folk medicine used for treating cancer, leukemia, hepatitis, rheumatism and other diseases. In this study, our objectives were to examine the total flavonoid and phenol content of different PP extracts (aqueous: HWEPP; ethanolic: EEPP; supercritical carbon dioxide: SCEPP-0, SCEPP-4 and SCEPP-5) and their antiproliferative effects in human lung cancer H661 cells. Among all the extracts tested, results showed that SCEPP-5 possessed the highest total flavonoid (226.19 +/- 4.15 mg/g) and phenol (100.82 +/- 6.25 mg/g) contents. SCEPP-5 also demonstrated the most potent inhibitory effect on H661 cell proliferation. Using DNA ladder and flow cytometry analysis, SCEPP-5 effectively induced H661 cell apoptosis as demonstrated by the accumulation of Sub-G1 peak and fragmentation of DNA. SCEPP-5 not only induced cell cycle arrest at S phase, it also up-regulated the expression of pro-apoptotic protein (Bax) and down-regulated the inhibitor of apoptosis protein (IAP). Furthermore, the apoptotic induction in H661 cells was found to associate with an elevated p53 protein expression, cytochrome c release, caspase-3 activation and PARP cleavage. Taken together, these results conclude that SCEPP-5 induced cell cycle arrest at S phase, and its apoptotic induction could be mediated through the p53-dependent pathway and modification of Bax and XIAP proteins expression. The results have also provided important pharmacological backgrounds for the potential use of PP supercritical fluid extract as products for cancer prevention.

Antioxidative and Hepatoprotective Effects of Physalis peruviana Extract against Acetaminophen-Induced Liver Injury in Rats

The aim of this study was to examine the antioxidant activities of Physalis peruviana L. (Solanaceae) aqueous extract (PPWE) and its protective effect against acetaminophen (APAP)-induced hepatotoxicity in rats. Using different models of antioxidant assay, namely ferric thiocyanate, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and reducing power, PPWE showed a dose-dependent increase in antioxidant activities, with total antioxidant activity (IC50: 0.81 μ g/ml) close to that of vitamin C (IC50: 0.89 μ g/ml). APAP at 850 mg/kg significantly increased the levels of serum glutamic pyruvic transaminase (sGPT), glutamic oxaloacetic transaminase (sGOT) and alkaline phosphatase (sALP). However, pre-treatment with PPWE at doses 150, 300, and 600 mg/kg body weight significantly prevented the increase in these enzymes, which are the major indicators of liver hepatitis. Biochemical assays of liver homogenate showed that PPWE at 150∼ 600 mg/kg significantly enhanced superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) concentrations, and diminished the level of thiobarbituric acid reactive substances (TBARS). Furthermore, liver histological observation also showed an obvious amelioration in the liver cell necrosis, liver lesion, and fatty changes in PP-treated groups. High performance liquid chromatographic analysis showed that ellagic acid (ca. 0.2%) but not others could be the major component contributing to the antioxidant and hepatoprotective activities of PPWE. The present study concludes that PPWE possesses antioxidant activity and potent hepatoprotective effect against APAP-induced liver injury in rats.

Tocotrienols Inhibited Growth and Induced Apoptosis in Human HeLa Cells Through the Cell Cycle Signaling Pathway

Tocotrienols of palm oil have been shown to possess potent neuroprotective, antioxidative, anticancer, and cholesterol-lowering activities. In this study, the authors examined the antiproliferative effects of α-, γ- and δ-tocotrienols (αT3, γT3, and δT3), and α-tocopherol (αT) in human cervical carcinoma (HeLa) cells. Their mechanism(s) of action on cell cycle signaling pathway were also investigated. Results showed that the antiproliferative effect of αT3 (IC50: 3.19 ± 0.05 µM) and γT3 (IC 50: 2.85 ± 0.07 µM) was more potent than δT3 (IC 50: >100 µM) and αT (IC50: 69.46 ± 3.01 µM). Both αT3 and γT3 also demonstrated a dose-dependent and time-dependent induction of cell death.They caused cell cycle arrest at G2/M phase and triggered apoptosis as displayed by the externalization of annexin V—targeted phosphatidylserine and accumulation of sub-G1 peak. At a concentration of 3 µM, αT3 downregulated the expression of cyclin D3, p16, and CDK6, while having no effect on cyclin D1, p15, p21, p27, and CDK4 expression. However, γT3 showed no effect on these proteins. The induction of HeLa cell apoptosis by αT3 and γT3 appeared to be associated with the expression of IL-6, but not the other cytokines (IFN-γ, IL-2, and IL-10).Taken together, the results suggest that αT3 and γT3 are more effective than δT3 and αT in inhibiting HeLa cell proliferation, and their mode of action could be through the upregulation of IL-6, and the downregulation of cyclin D3, p16, and CDK6 expression in the cell cycle signaling pathway.

Antiproliferative Activity of Cinnamomum cassia Constituents and Effects of Pifithrin-Alpha on Their Apoptotic Signaling Pathways in Hep G2 Cells

Cinnamaldehyde (Cin), cinnamic acid (Ca) and cinnamyl alcohol (Cal), major constituents of Cinnamomum cassia, have been shown to possess antioxidant, anti-inflammatory, anticancer and other activities. In this study, our aim was to evaluate the antiproliferative activity of these compounds in human hepatoma Hep G2 cells and examine the effects of pifithrin-alpha (PFTα; a specific p53 inhibitor) on their apoptotic signaling transduction mechanism. The antiproliferative activity was measured by XTT assay. Expression of apoptosis-related proteins was detected by western blotting. Results showed that at a concentration of 30 μM, the order of antiproliferative activity in Hep G2 cells was Cin > Ca > Cal. Cin (IC50 9.76 ± 0.67 μM) demonstrated an antiproliferative potency as good as 5-fluorouracil (an anti-cancer drug; IC50 9.57 ± 0.61 μM). Further studies on apoptotic mechanisms of Cin showed that it downregulated the expression of Bcl-XL, upregulated CD95 (APO-1), p53 and Bax proteins, as well as cleaving the poly (ADP-ribose) polymerase (PARP) in a time-dependent pattern. PFTα pre-incubation significantly diminished the effect of Cin-induced apoptosis. It markedly upregulated the anti-apoptotic (Bcl-XL) expression and downregulated the pro-apoptotic (Bax) expression, as well as effectively blocking the CD95 (APO-1) and p53 expression, and PARP cleavage in Cin-treated cells. This study indicates that Cin was the most potent antiproliferative constituent of C. cassia, and its apoptotic mechanism in Hep G2 cells could be mediated through the p53 induction and CD95 (APO-1) signaling pathways.

Armillariella mellea shows anti-inflammatory activity by inhibiting the expression of NO, iNOS, COX-2 and cytokines in THP-1 cells.

Armillariella mellea (AM), also known as Mi-Huan-Ku, a popular medicinal fungus used in the traditional Chinese medicine for treating headache, neurasthenia and insomnia. In the present study, our aim was to determine the effects of aqueous (AAM) and ethanol (EAM) extracts of A. mellea on lipopolysaccharide (LPS)-induced inflammatory response by measuring the inducible nitric oxide synthase (iNOS), cyclooxygenase-1 and -2 (COX-1 and COX-2) protein expression, cytokines (TNF-alpha, IL-4 and IL-8) formation, nitric oxide (NO) release and prostaglandin (PGE(2)) production in human monocytic (THP-1) cells. At concentration of 100 microg/ml, EAM, but not AAM, effectively protected against LPS-induced cell death in THP-1 cells. At concentrations of 10 approximately 100 microg/ml, EAM showed a potent anti-inflammatory activity as demonstrated by a dose-dependent inhibition of LPS (1 microg/ml)-induced release of NO and PGE(2), and significantly decreased the transcription of proinflammatory cytokines. EAM at 100 mug/ml significantly blocked the LPS induction of iNOS and COX-2 expression, but not COX-1. Therefore, the protective effect of EAM against LPS-induced inflammatory mediators release could explain, at least in part, its effectiveness in alleviating certain inflammatory related diseases.

Effects of vitamin E on the cinnamaldehyde-induced apoptotic mechanism in human PLC/PRF/5 cells.

1. Cinnamaldehyde has been shown to be effective in inducing cell apoptosis in a number of human cancer cells. The aim of the present study was to investigate the effect of vitamin E on the apoptotic signalling mechanism induced by cinnamaldehyde in human hepatoma PLC/PRF/5 cells.

γ-Tocotrienol induced cell cycle arrest and apoptosis via activating the Bax-mediated mitochondrial and AMPK signaling pathways in 3T3-L1 adipocytes

This study aimed to examine the anti-proliferative effects of α-, γ- and δ-tocotrienols (αT3, γT3 and δT3), and α-tocopherol on 3T3-L1 adipocytes. Results showed that compared with other vitamin E analogues, γT3 demonstrated the most potent anti-proliferative effect on 3T3-L1 cells. It significantly caused a reduction in mitochondrial membrane potential (Δψm) and an increase in ROS formation, as well as inducing cell apoptosis and cell cycle arrest at S phase. Further studies showed that it down-regulated Bcl-2 and PPAR-γ expression, suppressed Akt and ERK activation and phosphorylation, and caused cytochrome c release from mitochondria to cytosol, whereas it up-regulated CD95 (APO-1/CD95) and Bax expression, and caused caspase-3 and JNK activation, PARP cleavage and AMPK phosphorylation. Pretreatments with caspase-3 (z-DEVD-fmk) and AMPK (CC) inhibitors significantly suppressed the γT3-induced ROS production and cell death. Caspase-3 inhibitor also efficiently blocked CD95 (APO-1/CD95) and Bax expression, caspase-3 activation and PARP cleavage, whereas antioxidant N-acetyl-l-cysteine, AMPK inhibitor and AMPK siRNA effectively blocked the AMPK phosphorylation. Taken together, these results conclude that the potent anti-proliferative and anti-adipogenic effects of γT3 on 3T3-L1 adipocytes could be through the Bax-mediated mitochondrial and AMPK signaling pathways.