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In inflammation, the responses to noxious stimuli are controlled by the highly modulated interactions between various immune cells and chemical mediators. The purpose of this study is to evaluate and compare the anti-inflammatory effect of diterpenoids isolated from Andrographis paniculata, including dehydroandrographolide (AP1), andrographolide (AP2) and neoandrographolide (AP3), on the production of inflammatory cytokines and COX activities. Furthermore, the alteration of gene expression involved in this activity was investigated in the most potent compound to elucidate the other possible molecular mechanisms. AP1 (30.1 μM; 10 μg/ml) and AP2 (28.5 μM; 10 μg/ml) markedly inhibited COX-1 in ionophore A23187-induced human platelets. AP2 (28.5 μM) and AP3 (20.8 μM; 10 μg/ml) strongly suppressed the LPS-stimulated COX-2 activity in human blood. In addition, AP2 modulated the level of LPS-induced TNF-α, IL-6, IL-1β and IL-10 secretion in human blood in a concentration-dependent manner. The results revealed that AP2 exhibited the highest efficacy. Therefore, changes in the levels of mRNA transcripts by AP2 were further measured using human cDNA microarrays. The molecular response to AP2 was complex and mediated by various processes. Among the altered gene expressions, the genes involved in immune and inflammation processes were selectively down-regulated, such as cytokines and cytokine receptors (TNFSF14, TNF, TNFRSF6, and IL1A), chemokines (CCL8 and CXCL11), JAK/STAT signaling (JAK3 and STAT5A), TLRs family (TLR4 and TLR8) and NF-κB (NFKB1). Expression of some genes was validated using RT-PCR. The results demonstrated that AP1, AP2 and AP3 exhibited the anti-inflammatory effect by interfering COX and inflammatory cytokines and the underlying mechanisms of AP2 may be related to down-expression of genes involved in inflammatory cascade.

A new plant species, Barringtonia maunwongyathiae. W. Chuakul (Lecythidaceae), was recently discovered in Khuan Thon Forest, Ao Luek District, Krabi Province, Thailand. Chemical investigation of th...

A new cyclic 4-hydroxy-dithiosulfonate, bruguiesulfurol (1), as well as two known 4-hydroxydithiolane 1-oxides, brugierol (2) and isobrugierol (3) were isolated from the flowers of Bruguiera gymnorrhiza. With stably-transfected HepG2 cells, the three isolates activated antioxidant response element (ARE) luciferase activation with (EC(50)) values of 56.7, 3.7 and 1.8 microM, respectively. Compounds 2 and 3 also inhibited phorbol ester-induced NF-kappaB (nuclear factor-kappaB) luciferase activity with IC (50) values of 85.0 and 14.5 microM, respectively. In addition, compound 2 inhibited enzyme cyclooxygenase-2 (COX-2) activity with an IC(50) value of 6.1 microM. The structures of these isolates were determined by spectral data, and that of compound 1 was confirmed by X-ray crystallographic analysis.

Doxorubicin is an important and effective anticancer drug widely used for the treatment of various types of cancer but its clinical use is limited by dose-dependent cardiotoxicity. Elevated tissue levels of cellular superoxide anion/oxidative stress are a mechanism by which doxorubicin-induced cardiotoxicity. Selected medicinal plant extracts were tested for their antioxidant capacity and cardioprotective effect against doxorubicin-induced cardiotoxicity. The cardiac myoblasts H9c2 were incubated with the antioxidants ascorbic acid, trolox, N-acetylcysteine or selected medicinal plant extracts including; 1) ethanolic extracts from Curcuma longa L-EtOH Phyllanthus emblica L-EtOH, and Piper rostratum Roxb-EtOH; and 2) water extracts from Curcuma longa L-H2O and Morus alba L-H2O. The cardioprotective effects of these extracts were evaluated by crystal violet cytotoxicity assay. IC50s of doxorubicin were compared in the presence or absence of ascorbic acids, trolox, N-acetylcysteine or plant extracts. Morus alba L-H2O showed the highest antioxidant properties evaluated by ferric reducing/antioxidant power assay. Ascorbic acid and N-acetylcysteine had modest effects on the protection of doxorubicin-induced cytotoxicity while trolox showed insignificant protective effect. All plant extracts protected cardiac toxicity at different degrees except that Curcuma longa L-EtOH had no protective effect. Phyllanthus emblica-EtOH (100 microg/ml) showed the highest cardioprotective effect (approximately 12-fold doxorubicin IC50 increase). The data demonstrate that antioxidants from natural sources may be useful in the protection of cardiotoxicity in patients who receive doxorubicin.

The present study quantitatively investigated the antioxidant effects of the aqueous extracts from dried calyx of Hibiscus sabdariffa LINN. (roselle) in vitro using rat low-density lipoprotein (LDL). Formations of the conjugated dienes and thiobarbituric acid reactive substances (TBARs) were monitored as markers of the early and later stages of the oxidation of LDL, respectively. Thus, we demonstrated that the dried calyx extracts of roselle exhibits strong antioxidant activity in Cu(2+)-mediated oxidation of LDL (p

Extracts from 18 Thai traditional herbs were prepared by boiling with ethanol under a soxhlet apparatus and virucidal activity against fish pathogenic viruses (IHNV, OMV and IPNV) was tested by plaque reduction method using CHSE-214 cells. When the viruses were exposed to herb extract at 500μg/ml before inoculation to CHSE-214 cells, all herbs showed antiviral activity against IHNV and OMV, reducing plaques by 65-100% and 20-100%, respectively. However, in the case of IPNV, no plaque reduction was observed by any herbs tested. Some kinds of the herb extracts prevented viral infection, when CHSE-214 cells were treated with 100 μg/ml of herbs for 3h before viral infection. The percent of plaque reduction above 50% was observed in 6, 8 and 6 kinds of herb extracts for IHNV, OMV and IPNV, respectively. These extracts may inhibit the viral adsorption to the cells. When 100μg/ml of the herb extracts was applied for infected cells, the percent of plaque reduction above 50% was observed in 0.8 and 5 kinds of herb extracts for IHNV, OMV and IPNV, respectively. This means that some of the herb extracts may inhibit the replication of OMV and IPNV in CHSE-214, but no herb has any effect for IHNV infection. Moreover, all of the tested herb extracts showed low toxicity to CHSE-214 cell line, the cytotoxic 50% value being 1,200-41,500μg/ml.

Acetylenic compounds are of great interests in the development of the synthetic methodologies directed toward enediyne antitumor antibiotics. This paper discusses on the new asymmetric synthesis via heteroconjugate addition methodology by utilizing acetylide carbanions as the nucleophiles. On the other hand, silyl acetylenes can be nucleophiles under acidic condition and the products are quite useful as the precursor of heteroolefins. Most of the reactions undergo in highly stereoselective.

Phenylthioacetylene, as its lithium acetylide, was used for opening of epoxides to afford homopropargyl alcohols. Hydrosilylation of these acetylenes were followed by oxidation to afford the corresponding silylvinyl sulfones, the electrophile in the heteroconjugate addition, which showed very high selectivity. The stereocontrolled processes are discussed.

Phenylthioacetylene, as its lithium acetylide, was used for opening of epoxides to afford homopropargyl alcohols. Hydrosilylation of these acetylenes were followed by oxidation to afford the corresponding silylvinyl sulfones, the electrophile in the heteroconjugate addition, which showed very high selectivity. The stereocontrolled processes are discussed.

Acetylenic compounds are of great interests in the development of the synthetic methodologies directed toward enediyne antitumor antibiotics. This paper discusses on the new asymmetric synthesis via heteroconjugate addition methodology by utilizing acetylide carbanions as the nucleophiles. On the other hand, silyl acetylenes can be nucleophiles under acidic condition and the products are quite useful as the precursor of heteroolefins. Most of the reactions undergo in highly stereoselective.

The ethanolic extract of Kaempferia parviflora (KP) rhizomes dose-dependently relaxed both aortic rings and ileum precontracted with phenylephrine and acethylcholine, respectively.

Three new dammarane triterpenes, bruguierins A-C (1-3), were isolated from a petroleum ether extract of the flowers of Bruguiera gymnorrhiza. Their structures were determined on the basis of physical and spectroscopic data interpretation. With stably transfected HepG2 cells, the three isolates activated antioxidant response element (ARE luciferase activation) with EC(50) values of 7.8, 9.4, and 15.7 microM, respectively. Bruguierin A (1) also inhibited phorbol ester-induced NFkappaB (nuclear factor-kappaB) luciferase activation with an IC(50) value of 1.4 microM and selectively inhibited cyclooxygenase-2 (COX-2) activity with an IC(50) value of 0.37 microM. Compounds 2 and 3 were not active in these bioassays.

The rhizomes of Kaempferia parviflora (KP) (Zingiberaceae) have been used in Thai traditional medicine for health promotion and for the treatment of digestive disorders and gastric ulcer. This study investigated effect of KP on endothelial function. Studies in human umbilical vein endothelial cells (HUVEC) showed that KP dose-dependently increased nitrite concentrations in culture media after 48 h incubation. eNOS mRNA and protein expression were also enhanced. The induction of eNOS mRNA was detected at 4 h and plateau at 48 h while iNOS expression was not observed. These data demonstrate that KP has a great potential for a supplemental use in vascular endothelial health promotion.

Cardiac toxicity is a major adverse effect caused by doxorubicin (DOX) therapy. Many recent studies have shown that DOX toxicity involves generation of reactive oxygen species (ROS). Although protection or alleviation of DOX toxicity can be achieved by administration of antioxidant vitamins such as ascorbic acid and vitamin E, their cardioprotective effect remains controversial. Thus alternative naturally occurring antioxidants may potentially be candidates for antioxidant therapy. In this study, we investigated the antioxidative and cytoprotective effects of Phyllanthus urinaria (PU) against DOX toxicity using H9c2 cardiac myoblasts. The total antioxidant capacity of PU (1 mg/ml) was 5306.75+/-461.62 FRAP value (microM). DOX IC50 values were used to evaluate the cytoprotective effects of PU ethanolic extract (1 or 10 microg/ml) in comparison with those of ascorbic acid (VIT C, 100 microM) and N-acetylcysteine (NAC, 100 microM). PU treatments (1 or 10 microg/ml) dose dependently caused rightward DOX IC50 shifts of 2.8- and 8.5-fold, respectively while treatments with VIT C and NAC increased DOX IC50 by 3.3- and 4.2-fold, respectively. Additionally, lipid peroxidation and caspase-3 activity were parameters used to evaluate cytoprotective effect. All antioxidants completely inhibited cellular lipid peroxidation and caspase-3 activation induced by DOX (1 microM). Endogenous antioxidant defense such as total glutathione (tGSH), catalase and superoxide dismutase (SOD) activity was also modulated by the antioxidants. PU treatment alone dose dependently increased tGSH, and this effect was retained in the presence of DOX. Similar effect was observed in the assessment of catalase and SOD enzyme activity. The nuclear factor kappaB (NFkappaB) transcription factor assay demonstrated that all antioxidants significantly inhibited DOX-induced NFkappaB activation. Our results suggest that PU protection against DOX cardiotoxicity was mediated through multiple pathways and this plant may serve as an alternative source of antioxidants for prevention of DOX cardiotoxicity.