Decomposition of green tea and rooibos tea across three monospecific temperate forests: Effect of litter type and tree species.

We studied the effect of different forest covers on carbon (C) and nitrogen (N) dynamics of two standardised litters during decomposition in soil. For this purpose, commercially available bags containing green tea or rooibos tea were incubated in close monospecific stands of Fagus sylvatica, Pseudotsuga menziesii, and Quercus cerris, in the Apennines range, Italy, and then analysed at different intervals for up to two years. We also investigated the fate of various C functional groups in both types of litter under beech by nuclear magnetic resonance spectroscopy. After two years of incubation, green tea had not changed its original C/N ratio of 10, while rooibos tea had nearly halved its original value of 45, because of different C and N dynamics. Both litters progressively lost C, about fifty per cent of the initial content in the case of rooibos tea, and a little more for green tea, most of the loss occurring in the first three months. In terms of N, green tea behaved as for C, while rooibos tea in the early stage lost part of its N stock, fully recovering it by the end of the first year. Under beech, both litters showed a preferential loss in carbohydrates during the first trimester of incubation and, consequently, an indirect enrichment in lipids. Later on, the relative contribution of the various C forms remained practically constant. Our results overall support that the decay rate and compositional changes of litter depend strongly on the litter type and little on the tree cover of the soil in which the litter is incubated.

Inhibitory Effects of Chung Hun Wha Dam Tang (CHWDT) on High-Fat Diet-Induced Obesity via AMP-Activated Protein Kinase Activation.

The Chung Hun Wha Dam Tang (CHWDT) herbal combination was reported to cease dizziness and phlegm. However, the effect of CHWDT in obesity has not yet been known mechanically. Therefore, we investigated whether this CHWDT could protect the cells from lipogenesis, gluconeogenesis, and inflammation in both in vivo and in vitro. CHWDT significantly decreased body weight, epididymal and perirenal fat content without affecting feed intake in high-fat diet-induced obese mice model. Additionally, CHWDT inhibited obesity-induced SREBP1, FAS, PGC1α, G6Pase, PEPCK and increased CPT1, ACO, and LCAD genes expression in vivo and in vitro. Proinflammatory cytokines like TNF-α and iNOS expression were reduced by CHWDT in both Raw264.7 macrophages and HepG2 cells. In addition, NO production was also significantly decreased by CHWDT in LPS-stimulated macrophages. Furthermore, AMPKα activation by CHWDT was involved in inhibition of obesity by reducing triglycerides production and increasing CPT1 expression. Based on all of the results, we suggest that CHWDT has inhibitory effects on obesity-induced lipogenesis, gluconeogenesis, and inflammation via AMPKα activation.

Okanin, a chalcone found in the genus Bidens, and 3-penten-2-one inhibit inducible nitric oxide synthase expression via heme oxygenase-1 induction in RAW264.7 macrophages activated with lipopolysaccharide.

Excess production of nitric oxide by activated macrophages via inducible nitric oxide synthase leads to the development of various inflammatory diseases. Heme oxygenase-1 expression via activation of nuclear factor-erythroid 2-related factor 2 inhibits nitric oxide production and inducible nitric oxide synthase expression in activated macrophages. Okanin is one of the most abundant chalcones found in the genus Bidens (Asteraceae) that is used as various folk medications in Korea and China for treating inflammation. Here, we found that okanin (possessing the α-ß unsaturated carbonyl group) induced heme oxygenase-1 expression via nuclear factor-erythroid 2-related factor 2 activation in RAW264.7 macrophages. 3-Penten-2-one, of which structure, as in okanin, possesses the α-ß unsaturated carbonyl group, also induced nuclear factor-erythroid 2-related factor 2-dependent heme oxygenase-1 expression, while both 2-pentanone (lacking a double bond) and 2-pentene (lacking a carbonyl group) were virtually inactive. In lipopolysaccharide-activated RAW264.7 macrophages, both okanin and 3-penten-2-one inhibited nitric oxide production and inducible nitric oxide synthase expression via heme oxygenase-1 expression. Collectively, our findings suggest that by virtue of its α-ß unsaturated carbonyl functional group, okanin can inhibit nitric oxide production and inducible nitric oxide synthase expression via nuclear factor-erythroid 2-related factor 2-dependent heme oxygenase-1 expression in lipopolysaccharide-activated macrophages.

Cytoprotective constituents of the heartwood of Caesalpinia sappan on glutamate-induced oxidative damage in HT22 cells.

The bioassay-guided fractionation of a MeOH extract of the heartwood of Caesalpinia sappan L. provided two neuroprotective compounds, sappanchalcone (2) and 4-O-methylepisappanol (3), together with a methoxychalcone, isoliquiritigenin 2'-methyl ether (1), and three aromatic compounds, 4-O-methylsappanol (4), caesalpine J (5), pluchoic acid (6). At concentrations of 20-40 microM, compound 2 showed significant cytoprotective effects against glutamate-induced oxidative stress through the induction of heme oxygenase (HO)-1 in HT22-immortalized hippocampal cells. Compound 3 also showed moderate neuroprotective effect at 40 microM, but compounds 1, 4-6 did not show any protective effects against glutamate-induced cytotoxicity in HT22 cells.

The alpha-methylene-gamma-butyrolactone moiety in dehydrocostus lactone is responsible for cytoprotective heme oxygenase-1 expression through activation of the nuclear factor E2-related factor 2 in HepG2 cells.

Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a major role in the pathogenesis of several diseases. The alpha-methylene-gamma-butyrolactone (CH2-BL) structural unit, which characterizes a group of naturally occurring sesquiterpene lactones, is known to possess numerous biological activities. In the present study, we evaluated dehydrocostus lactone possessing CH2-BL moiety, one of the bioactive constituents of the medicinal plant Saussurea lappa, as an inducer of cytoprotective HO-1. In HepG2 cells, treatment with dehydrocostus lactone induced HO-1 expression and increased HO activity in a concentration-dependent manner. Similar results were also observed when the cells were incubated with CH2-BL, a parent structure of dehydrocostus lactone. In contrast, mokko lactone, a reduced product of dehydrocostus lactone, and alpha-methyl-gamma-butyrolactone (CH3-BL), a parent structure of mokko lactone, did not induce HO-1 expression. Pretreatment with either dehydrocostus lactone or CH2-BL for 6 h protected the cells from hydrogen peroxide-mediated toxicity, whereas mokko lactone or CH3-BL failed to exert a cytoprotective action. Inhibition of HO-1 expression by HO-1 small interfering RNA (siRNA) abrogated cellular protection afforded by dehydrocostus lactone or CH2-BL. In addition, dehydrocostus lactone caused the nuclear accumulation of the nuclear factor E2-related factor 2 (Nrf2) and increased the promoter activity of antioxidant response element (ARE). Using Nrf2 siRNA, Nrf2 activation was confirmed to contribute to cytoprotective HO-1 expression by dehydrocostus lactone or CH2-BL. Collectively, our findings suggest that CH2-BL moiety in dehydrocostus lactone increases cellular resistance to oxidant injury in HepG2 cells, presumably through Nrf2/ARE-dependent HO-1 expression.

Effects of oral administration of Phellinus linteus on the production of Th1- and Th2-type cytokines in mice.

The mushroom Phellinus linteus (PL) has been shown to have antitumor and immunostimulatory effects. We hypothesized that the hot water extract of PL (WEPL) exerts its significant immunostimulatory effect by inducing production of the Th1-derived cytokine interferon-gamma (IFN-gamma) by T lymphocytes. T lymphocytes were isolated from the mice fed with 200 mg/kg of WEPL once a day for 4 weeks and then stimulated with the mitogen concanavaline A (Con A). IFN-gamma gene and intracellular protein expressions were analyzed by RT-PCR and flow cytometry, respectively. The production of IFN-gamma was measured by enzyme-linked immunosorbent assay. WEPL significantly enhanced the transcription of IFN-gamma mRNA. The effect of WEPL on IFN-gamma expression was further supported by a concomitant increase in the number of cells with intracellular IFN-gamma protein as well as the secretion of IFN-gamma. However, WEPL did not modulate either gene expression or protein secretion of interleukin-4, a Th2-associated cytokine, by Con A-stimulated T lymphocytes. Our results demonstrate that one of the potentially beneficial antitumor and immunostimulatory effects of WEPL may be mediated through the enhancement of IFN-gamma secretion by T lymphocytes.

Scoparone from Artemisia capillaris inhibits the release of inflammatory mediators in RAW 264.7 cells upon stimulation cells by interferon-gamma Plus LPS.

Scoparone is a major component of the shoot of Artemisia capillaris (Compositae), which has been used for the treatment of hepatitis and biliary tract infection in oriental countries. In the present study we observed that, scorparone exhibited no cytotoxic effect in unstimulated macrophages, but reduced the release of nitric oxide (NO) and prostaglandin E2 (PGE2) upon stimulation by IFN-gamma/LPS or LPS. The inhibitory effects were found to be in conjuction with the suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in IFN-gamma/LPS stimulated RAW 264.7 cells. Moreover, scoparone also attenuated the production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 in LPS-stimulated RAW264.7 cells. These results suggest that scoparone decreases the production of the inflammatory mediators such as NO and PGE2 in macrophages by inhibiting iNOS and COX-2 expression.

Isolation of angiotensin converting enzyme (ACE) inhibitory flavonoids from Sedum sarmentosum.

Bioassay-guided fractionation of the EtOAc-soluble extract of Sedum sarmentosum afforded a new flavonoid, quercetin-3-O-alpha-(6'''-caffeoylglucosyl-beta-1,2-rhamnoside) (1), along with four known flavonoids, quercetin 3-O-alpha-(6'''-p-coumaroylglucosyl-beta-1,2-rhamnoside) (2), isorhamnetin-3-beta-glucopyranoside (3), quercetin-3-beta-glucopyranoside (4), and kaempferol-3-alpha-arabinopyranoside (5). Purification of these compounds was conducted with the application of various chromatographic methods. Compounds 1-5 inhibited angiotensin I converting enzyme (ACE) activity in a concentration-dependent manner. Compounds 1-5 had 50% inhibitory concentration values of 158.9+/-11.1 microgM, 351.6+/-3.9 microgM, 408.9+/-4.6 microgM, 708.8+/-23.1 microgM, and 392.8+/-13.4 microgM.

4-Acetyl-12,13-epoxyl-9-trichothecene-3, 15-diol from Isaria japonica mediates apoptosis of rat bladder carcinoma NBT-II cells by decreasing anti-apoptotic Bcl-2 expression and increasing pro-apoptotic Bax expression.

We studied the effect of 4-acetyl-12,13-epoxyl-9-trichothecene-3, 15-diol (AETD) isolated from Isaria japonica, one of the most popular Chinese fungal medicines, on the induction of apoptosis in rat bladder carcinoma NBT-II cells. AETD was cytotoxic to NBT-II cells, and this cytotoxic effect appears to be attributed to its induction of apoptotic cell death, as AETD induced nuclear morphological changes and internucleosomal DNA fragmentation, and increased the proportion of hypodiploid cells and activity of caspase-3. AETD treatment also decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the pro-apoptotic protein Bax. These results provide important information in understanding the mechanism(s) of AETD-induced apoptosis.

Four glycosides from the leaves of Abeliophyllum distichum with inhibitory effects on angiotensin converting enzyme.

The bioassay-guided fractionation of the n-BuOH extract of Abeliophyllum distichum afforded acteoside (1), isoacteoside (2), rutin (3), and hirsutrin (4). Compounds 1-3 moderately inhibited the angiotensin I converting enzyme activity in a dose-dependent manner. Compounds 1-3 showed the 50% inhibitory concentration values of 228 micro g/mL, 290 micro g/mL, and 278 micro g/mL, respectively.

Inhibition of inducible nitric oxide synthesis by catalposide from Catalpa ovata.

Catalposide (1) and two related iridoids were isolated from the stem of Catalpa ovata (Bignoniaceae) by bioassay guided fractionation. Catalposide (1) significantly inhibited the production of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages in a dose-dependent manner. RT-PCR and Western blot analyses demonstrated that catalposide (1) suppressed the expression of inducible nitric oxide synthase (iNOS) gene and iNOS protein. Catalposide (1) also inhibited the activation of LPS-induced NF-kappaB as analyzed by electrophoretic mobility shift assay (EMSA). In addition to the inhibitory effect on NO production in LPS-stimulated RAW 264.7 cells, catalposide (1) significantly inhibited the NO production in cytokine-stimulated human DLD-1 and rat vascular smooth muscle (VSM) cells in a dose-dependent manner.

Germination inhibitory constituents from Erigeron annuus.

(5-Butyl-3-oxo-2,3-dihydrofuran-2-yl)-acetic acid was isolated from the flowers of Erigeron annuus as one of four germination inhibitory constituents. Its structure was determined by analysis of MS and NMR spectroscopic data. Three known compounds, 3-hydroxy-pyran-4-one, 4-hydroxycinnamic acid, and 3,4-dihydroxycinnamic acid methyl ester were also identified as active constituents. These compounds showed 50% inhibitory effects (IC(50)) on the germination of lettuce seed at concentrations of 2.13+/-0.03, 12.85+/-0.56, 4.97+/-0.24, and 4.87+/-0.25 mM, respectively. 4-Hydroxybenzoic acid was used as a positive control, displaying an IC(50) value of 4.02+/-0.39 mM.

Imperatorin, a furanocoumarin from Angelica dahurica (Umbelliferae), induces cytochrome c-dependent apoptosis in human promyelocytic leukaemia, HL-60 Cells.

Imperatorin, a biologically active furanocoumarin from the roots of Angelica dahurica (Umbelliferae), was found to induce apoptosis in human promyelocytic leukaemia, HL-60 cells. DNA fragmentation assay, morphology-based evaluation, and flow cytometric analysis demonstrated that imperatorin at micromolar concentrations was able to trigger apoptosis of HL-60 cells. Neither necrosis nor differentiation was observed at cytotoxic micromolar concentrations of imperatorin. Further studies showed that the cytochrome c/caspase-9 pathway was responsible for imperatorin-induced apoptosis; i.e., mitochondrial membrane was depolarized, Bcl-2 was down-regulated, cytochrome c was released from mitochondria, caspase-9 and caspase-3 were activated, and poly(ADP-ribose) polymerase was cleaved. Furthermore, imperatorin-induced apoptosis was significantly blocked by Z-VAD-FMK (a broad spectrum caspase inhibitor), Z-LEHD-FMK (a caspase-9 inhibitor) and Ac-DMQD-CHO (a caspase-3 inhibitor), but not by Z-IEDT-FMK (a caspase-8 inhibitor).

1,2,3,4,6-Penta-O-galloyl-beta-D-glucose protects rat neuronal cells (Neuro 2A) from hydrogen peroxide-mediated cell death via the induction of heme oxygenase-1.

The root of Paeonia suffruticosa ANDREWS is an important Chinese crude drug used in many traditional prescriptions. 1,2,3,4,6-Penta-O-galloyl-beta-D-glucose (PGG), a major component of this crude drug, has been shown to possess potent anti-oxidant, anti-mutagenic and anti-proliferative effects. In the present study, we examined the effect of PGG on the expression of neuronal heme oxygenase-1 (HO-1), an inducible stress protein that degrades heme to the neuroactive molecule, carbon monoxide and the anti-oxidant, biliverdin. Exposure of Neuro 2A cells to PGG (10-50 microM) resulted in a concentration- and time-dependent induction of HO-1 mRNA, and protein expressions and heme oxygenase activity. Interestingly, pretreatment of the neuronal cells with PGG resulted in enhanced cellular resistance to hydrogen peroxide. This cytoprotective effect was reversed by zinc protoporphyrin IX, an inhibitor of heme oxygenase. This study showed that PGG could protect neuronal cells from oxidative stress via the induction of HO-1 gene expression.

Furocoumarins from Angelica dahurica with hepatoprotective activity on tacrine-induced cytotoxicity in Hep G2 cells.

Fractionation of the MeOH extract of Angelica dahurica Benth et Hook resulted in the isolation of six furocoumarins, imperatorin (1), isoimperatorin (2), (+/-)-byakangelicol (3), (+)-oxypeucedanin (4), (+)-byakangelicin (5), and (+)-aviprin (6). Among these, compounds 1 and 5 exhibited strong hepatoprotective activities, displaying EC(50) values of 36.6 +/- 0.98 and 47.9 +/- 4.6 microM, respectively. Compounds 3 and 4 showed moderate activities with EC(50) values of 112.7 +/- 5.35 and 286.7 +/- 6.36 microM, respectively. Silybin as a positive control showed the EC(50) value with 69.0 +/- 3.4 microM. Comparison of hepatoprotective activities for six furocoumarins 1 - 6 suggested that oxy-substitution at the C-9 position increased the hepatoprotective activity.

(3R,6R)-4-methyl-6-(1-methylethyl)-3-phenylmethyl-perhydro-1,4-oxazine-2,5-dione: an apoptosis-inducer from the fruiting bodies of Isaria japonica.

(3R,6R)-4-methyl-6-(1-methylethyl)-3-phenylmethylperhydro-1,4-oxazine-2,5-dione (1) was isolated from the fruiting bodies of Isaria japonica as an apoptosis-inducing agent. The complete structural assignment of the compound was accomplished on the basis of spectroscopic methods and chemical transformations. Compound 1 induced apoptotic cell death of the human leukemia cells (HL-60) in a dose-dependent manner, ranging from 5.0 microg/ml to 100.0 microg/ml.