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Yew-Min Tzeng

Publications and source records attributed to Yew-Min Tzeng.

13 recordsLinked to original sources
PubMed2006

Biological evaluation of sulfone derivatives as anti-inflammatory and tumor cells growth inhibitory agents.

A variety of sulfone derivatives including three dimethyl arylsulfonyl malonates (1-3), two bis-(arylethenesulfonyl)-vinyl benzenes (4 and 5) and a sulfone triazole (6) were evaluated for their anti-inflammatory as well as tumor cells growth inhibitory activities in vitro. The sulfone derivatives 1, 2, 3 and 6 significantly and dose-dependently inhibited the production of inflammatory mediators such as nitric oxide (NO), and cytokines (tumor necrosis factor (TNF)-alpha and interleukin (IL)-12), in lipopolysaccharide (LPS) and interferon (IFN)-gamma activated murine peritoneal macrophages, without displaying cytotoxicity. The inhibitory mechanism is found through reducing iNOS protein expression. In addition, the derivatives 1-3 significantly arrest mitogen-stimulated spleen cells in G0/G1 stage, whereas compounds 4-6 blocked the same in the G2/M phase. Furthermore, the sulfone derivatives 3 and 6 showed dramatically reduction in the ratio of IFN-gamma to IL-4 production from mitogen-stimulated spleen cells. On the other hand, the novel compounds exhibited interesting cytotoxic activities against a panel of cell lines, particularly, 20 muM of compound 3 showed 50% cytotoxic effect on human hepatoma cell line, but has no effect on normal human peripheral blood mononuclear cells. In conclusion, compound 3 showed interesting anti-inflammatory and tumor cells growth inhibitory functions.

Animals↗
PubMed2006

Antioxidants enhanced production of destruxin E from cultivation of Metarhizium anisopliae.

The effect of antioxidants on the production of an important cyclohexadepsipeptide congener destruxin E (dtx E) was investigated using the entomopathogenic fungus Metarhizium anisopliae F061. In shaker flask cultivations, 0.015% of menadione-enhanced dtx E production of 220.4 mg/l compared to the control cultivation 90.2 mg/l, which was illustrated by stimulation of dtx E biosynthesis through two electron reduction DT-diaphorase processes in cultivation of M. anisopliae. In 5-l stirred-tank bioreactor cultivation with menadione addition and of control pH 4.0, a yield of 454.6 mg/l of dtx E was obtained after 7 days, and was nearly 30 and 15-fold higher than that from no pH control, and controlled pH 2.0 cultivations, respectively. Further cultivation in a 20-l airlift bioreactor, at pH 4.0, dtx E obtained on the 9th day was 406.0 mg/l, which was much higher than the standard cultivation of no pH control yield 203.3 mg/l on the 11th day. Thus, the present study provides useful information for enhancing dtx E production in cultivation.

Antioxidants↗
PubMed2005

Anti-inflammatory activities of constituents isolated from Phyllanthus polyphyllus.

Four compounds, including one benzenoid, 4-O-methylgallic acid (1), together with three arylnaphthalide lignans, namely phyllamyricin C (2), justicidin B (3) and diphyllin (4) were isolated from the whole plants of Phyllanthus polyphyllus L. (Euphorbiaceae). This was the first isolation report of compounds 1-4 from this plant species. The in vitro inhibitory effects of these compounds were evaluated on the production of nitric oxide (NO) and cytokines (tumor necrosis factor (TNF)-alpha and interleukin (IL)-12), from LPS/IFN-gamma activated murine peritoneal macrophages. The results indicated that the 50% inhibition concentration (IC(50)) values of NO production from activated peritoneal macrophages by compounds 1-4 were 100, 25, 12.5 and 50 microM, respectively. In parallel, these dilutions were approximately inhibited in a similar manner to that observed for cytokines (TNF-alpha, and IL-12) production. On the other hand, at 100 microM concentration compounds 3 and 4 showed 50% inhibition of NO production from peritoneal macrophages that had been pre-activated with LPS/IFN-gamma for 24h, whereas compounds 1 and 2 inhibited only about 20 and 10%, respectively. These results support the use of this plant for the treatment of inflammatory diseases in oriental traditional medicine.

Animals↗
PubMed2005

Anti-inflammatory activities of flavonoids isolated from Caesalpinia pulcherrima.

The anti-inflammatory activities of five flavonoids, namely 5,7-dimethoxyflavanone (1), 5,7-dimethoxy-3',4'-methylenedioxyflavanone (2), isobonducellin (3), 2'-hydroxy-2,3,4',6'-tetramethoxychalcone (4) and bonducellin (5), all of them isolated from Caesalpinia pulcherrima L. was studied in lipopolysaccharide (LPS) and interferon (IFN)-gamma activated murine peritoneal macrophages. These five compounds significantly and dose-dependently inhibited the inflammatory mediators; nitric oxide (NO), and cytokines [tumor necrosis factor (TNF)-alpha and interleukin (IL)-12]. According to their inhibitory results, the order of anti-inflammatory potency was compounds 3>5>4>2>1. Furthermore, peritoneal macrophages were pre-activated with LPS/IFN-gamma for 24h, and determined the inhibitory effects of the above-mentioned isolates on the production of NO after a further 24h. The present study supports the use of Caesalpinia pulcherrima for the treatment of inflammatory diseases in traditional medicine. This is the first study on compounds 1-5 about their anti-inflammatory activities.

Animals↗
PubMed2005

Synthesis, growth inhibition, and cell cycle evaluations of novel flavonoid derivatives.

As a continuation of our search for potential new anticancer agents, a series of ten flavonoid derivatives has been synthesized by cyclization of substituted chalcones. Target compounds were evaluated for their biological activity. Among them, compounds 1-4 and 9 displayed a significant growth inhibitory action against a panel of tumor cell lines including Jurkat, PC-3, and Colon 205. On treatment with an equitoxic (IC50) concentration, compounds 1-5 and 7-9 blocked cells in the G2/M phase of the Jurkat cell cycle, whereas compound 6 blocked the same in the G0/G1 phase.

Cell Cycle↗
PubMed2005

Inhibitory effects of flavonol glycosides from Cinnamomum osmophloeum on inflammatory mediators in LPS/IFN-gamma-activated murine macrophages.

Four kaempferol glycosides were isolated from the leaves of Cinnamomum osmophloeum Kaneh, a Taiwan endemic tree. These compounds namely, kaempferitrin (1), kaempferol 3-O-beta-D-glucopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-7-O-alpha-L-rhamnopyranoside (2), kaempferol 3-O-beta-D-apiofuranosyl-(1-->2)-alpha-L-arabinofuranosyl-7-O-alpha-L-rhamnopyranoside (3), and kaempferol 3-O-beta-D-apiofuranosy-(1-->4)-alpha-L-rhamnopyranosyl-7-O-alpha-L-rhamnopyranoside (4). The structure of compound 2 was determined by spectroscopic analyses and acid hydrolysis. The isolates 1-4 were evaluated as inhibitors of some macrophage functions involved in the inflammatory process. These four compounds inhibited lipopolysaccharide (LPS) and interferon (IFN)-gamma-induced nitric oxide (NO), and cytokines [tumor necrosis factor (TNF)-alpha and interleukin (IL)-12] in a dose-dependent manner. The concentration of 50% inhibition (IC(50)) of NO by compounds 1, 3, 4 were 40, 15, 20microM, respectively. In parallel, these concentrations were approximately in a similar manner to that observed for TNF-alpha and IL-12 production. However, compound 2 inhibited NO and cytokines production by 30% at 100microM concentration. On the other hand, compounds 3 and 4 showed no inhibitory effect on the production of NO from macrophages, when inducible NO synthase was already expressed by the stimulation with LPS and IFN-gamma. Taken together, our results provide evidence that isolates of C. osmophloeum possess an anti-inflammatory potential which constitutes a previously unrecognized biological activity.

Animals↗
PubMed2005

Circular dichroism analysis of destruxins from Metarhizium anisopliae.

Destruxins are secondary metabolites secreted by Metarhizium anisopliae [Y. Kodaira, Toxic substances to insects, produced by Aspergillus ochraceus and Oopsra destructor, Agric. Biol. Chem., 25 (1961) 261-262. D.W. Roberts, Toxins from the entomogenous fungus Metarhizium anisoplaie: Isolation from submerged cultures, J. Invertebr. Pathol., 14 (1969) 82-88. D.W. Roberts, Toxins from the entomogenic fungi in microbial control of pest and plant disease, Academic press, New York, 1981, pp441-464.]. In recent research, other than being used as insecticides, destruxins exhibited great potential in therapeutical applications such as antitumor, antivirus, and animal cell immunization effectiveness, etc. In this study, the conformations purified destruxins were determined by circular dichroism (CD). The results indicated that these cyclic peptides have the type I beta-turn conformation. In addition, different types of destruxins exhibited different CD spectra in acetonitrile. Therefore, these characters can be used as fingerprints to identify each type of destruxin. To further investigate the interactions among destruxins, various combinations of destruxins in 10 mM phosphate-buffered saline (PBS) were also studied by CD. The results strongly suggested that destruxins might work independently in vivo. To our knowledge, this is the first report presenting the CD analysis of purified destruxins.

Circular Dichroism↗
PubMed2005

Inhibitory effects of the flavonoids isolated from Waltheria indica on the production of NO, TNF-alpha and IL-12 in activated macrophages.

Three flavonoids were isolated from the whole plants of Waltheria indica and biological properties investigated. On the basis of their spectroscopic data, these compounds were identified as (-)-epicatechin, quercetin, and tiliroside. These flavonoids significantly and dose-dependently inhibited the production of the inflammatory mediator nitric oxide (NO), and the cytokines (tumor necrosis factor (TNF)-alpha and interleukin (IL)-12), in lipopolysaccharide (LPS) and interferon (IFN)-gamma activated murine peritoneal macrophages, without displaying cytotoxicity. The order of inhibitory activity was quercetin>tiliroside>(-)-epicatechin. Furthermore, peritoneal macrophages were pre-activated with LPS/IFN-gamma for 24 h, and the inhibitory effects of the above mentioned isolates on the production of NO were determined after a further 24 h, to address the possible mechanisms of their action. The present study supports the use of W. indica for the treatment of inflammatory diseases in traditional medicine.

Animals↗
PubMed2004

Differential effects of synthesized 2'-oxygenated chalcone derivatives: modulation of human cell cycle phase distribution.

Ten structurally related 2'-oxygenated chalcone derivatives, bearing either hydroxy and/or methoxy substituents on the A and B rings, were synthesized through Claisen-Schmidt condensation. The synthesis procedure was relatively easy and had an acceptable yield. The in vitro cytotoxicities of these compounds against the human tumor cells such as Jurkat, U937 cells, and normal cells PHA stimulated PBMCs were investigated. Among those, compounds 1 (IC50 = 2.5 microM), 2 (1.7 microM), and 8 (3.2 microM) showed potent inhibitory activity toward Jurkat cell line. In parallel, compounds 1 (6.7 microM), 2 (1.5 microM), and 10 (5.3 microM) showed the highest activity against U937 cell line. However, the chalcones also inhibit the PHA stimulated PBMCs cells, but the IC50 values were relatively high when compared to the tumor cell line values. Studies were also on the effect of synthesized chalcones on the cell cycle phase distribution. In Jurkat cell line, compounds 7 and 9 showed the highest activity and the most striking effect in reduction of the percentage of cells in the S phase, which was associated with an increase of cells in G2/M phase. In U937 cell line, compound 3 increased the proportion of cells in the G0/G1 phase and reduced the proportion in S phase. In contrast, compounds 1, 9, and 10 showed a decrease effect on the percentage of cells in S phase and an increase effect on the percentage of cells in the G2/M phase of the cell cycle. Whereas in the case of PHA stimulated PBMCs, compounds 1, 4, 8, and 10 increased the percentage of cells in G2/M phase, which was associated with a decrease effect in the S phase of the cell cycle.

Antineoplastic Agents↗
PubMed2004

Flavonoids and andrographolides from Andrographis paniculata.

Two flavonoids, identified as 5,7,2',3'-tetramethoxyflavanone and 5-hydroxy-7,2',3'-trimethoxyflavone, as well as several other flavonoids, andrographolide diterpenoids, and polyphenols, were obtained from the phytochemical investigation of the whole plant of Andrographis paniculata, a well known medicinal plant. The structures of these compounds were established with the aid of spectroscopic methods, including analysis by 2D NMR spectroscopy.

Andrographis↗
PubMed2004

Analysis of destruxins produced from Metarhizium anisopliae by capillary electrophoresis.

Destruxins are insecticidal metabolites of a fungus, Metarhizium anisopliae. These metabolites are usually secreted into the culture medium during growth. The structure of destruxins is classified as being a cyclic hexadepsipeptide. More than 35 different destruxins have been characterized with a wide range of insecticidal activities. In this report, the destruxins are extracted by acetonitrile and crystallization by lyophilization. The final crystal is subjected for capillary electrophoresis analysis. Because destruxins are relatively hydrophobic compounds, micellar electrokinetic capillary chromatography is used in this series of experiments. The borate-based running buffer is optimized according to (1) boric acid concentration, (2) sodium dodecyl sulfate (SDS) concentration, (3) acetonitrile concentration, and (4) the pH of the running buffer. Optimization is based on resolution and running speed. The results indicate that 20 mM boric acid with 40 mM SDS plus 10% acetonitrile with pH 9.24 is the best set of conditions for both resolution and running speed.

Ascomycota↗
PubMed2003

Pulmonary toxicity of thuringiensin administered intratracheally in Sprague-Dawley rats.

The purpose of this work is to evaluate the pulmonary toxicity of purified thuringiensin in Sprague-Dawley rats. Rats were intratracheally instillated with 0, 0.4, 0.8, 1.6, 3.2, 6.4 and 9.6 mg/kg body weight of thuringiensin. The results indicated that the acute pulmonary LD(50) of thuringiensin for rats was 4.4 mg/kg. The total number of inflammatory cells and lactate dehydrogenase (LDH) activity in the bronchoalveolar lavage (BAL) fluid increased in a dose-dependent manner after thuringiensin instillation. Furthermore, an effective dose of 1.6 mg/kg was selected for the time course study of pulmonary toxicity. The treated animals showed a significant increase in the weights of the lungs, hydroxyproline levels in the lungs and total number of cells in BAL fluid 2, 4, 7, 14, 28 and 56 days after treatment. In comparison with the control, the total protein concentrations in BAL fluid were increased by 361, 615, 116, 41, 34 and 41%, after 2, 4, 7, 14, 28 and 56 days, respectively. The LDH activity in BAL fluid showed a significant increase after 1, 2, 4, 7, 14, 28 and 56 days. The increases in fibronectin levels were 164, 552, 490, 769, 335, 257 and 61% at the corresponding times, but neither tumor necrosis factor nor interleukin-1 increased. The treated rats presented abnormal histology including distributed inflammation in the bronchioles and alveoli, bronchial cellular necrosis on days 1 and 2, and areas of septal thickening with cellular infiltration and collagen deposit in the intestinal and alveolar spaces on days 4-56. Based on these biochemical and pathological parameters, intratracheal instillation of purified thuringiensin might cause significant pulmonary toxicity in rats.

Adenosine↗