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Xylongoic acids A–C, three isopimarane diterpene derivatives were isolated from the rice cultures of Xylaria longipes HFG1018, a fungicolous fungus isolated from the fruiting bodies of the wood-decay and medicinal fungus Fomitopsis betulina. The structures of the isolated compounds were determined by extensive analysis of NMR and HRESIMS data.

Endometrial cancer is generally one of the most evident malignant tumours of the female reproductive system, and the mechanisms underlying its cell proliferation and apoptosis are key to research in gynaecological oncology. In the paper, the in-depth molecular mechanism by which DJ-1 protein regulates the proliferation and apoptosis of Ishikawa cells was investigated. DJ-1 knockdown and overexpressing Ishikawa stable cell lines were established by lentiviral transduction. The levels of DJ-1 and noncanonical NF-κB signaling proteins were evaluated by Western blotting. Cell counting kit-8 (CCK-8) and flow cytometry were applied to analyze the cell viability and apoptosis. Co-immunoprecipitation experiment was utilized to assess the DJ-1-Cezanne interaction. The results showed that DJ-1 overexpression conferred apoptosis resistance and high proliferation on Ishikawa cells, while DJ-1 knockdown in Ishikawa cells produced the opposite results. These findings again suggested that DJ-1 inhibits the apoptosis and promotes the proliferation of Ishikawa cells. More crucially, further data showed that the noncanonical NF-κB activation was required for the regulation of Ishikawa cell proliferation and apoptosis by DJ-1. Meanwhile, it was found that noncanonical NF-κB pathway may be activated by DJ-1 interacting with and negatively regulating Cezanne in Ishikawa cells. Overall, this work revealed that DJ-1 associates with and negatively regulates Cezanne and consequently triggers the noncanonical NF-κB activation, thereby regulating Ishikawa cell proliferation and apoptosis.

Prenyltransferase (PTase) enzymes play crucial roles in natural product biosynthesis by transferring isoprene unit(s) to target substrates, thereby generating prenylated compounds. The prenylation step leads to a diverse group of natural products with improved membrane affinity and enhanced bioactivity, as compared to the non-prenylated forms. The last two decades have witnessed increasing studies on the identification, characterization, enzyme engineering, and synthetic biology of microbial PTase family enzymes. We herein summarize several examples of microbial soluble aromatic PTases for chemoenzymatic syntheses of unnatural novel prenylated compounds.

A new irlactane-type, namely irlactin K (1), and 22 tremulane-type sesquiterpenes including fourteen previously undescribed ones, namely irpexolactins A–N (2–15), and a known irlactane-type sesquiterpenoid, were isolated from the fermentation broth of the medicinal fungus Irpex lacteus HFG1102. The structures of all the isolates were characterized by extensive spectroscopic methods, including 1D and 2D NMR and MS spectroscopic analysis. The absolute configurations of irlactin K and the known compound conocenol B (20) were established by single-crystal X-ray diffraction analysis. The vasorelaxant effects of irlactin K (1), irpexolactins A (2), C (4), K (12), and irlactam (22) were evaluated. Graphic Abstract

Eighteen new nor-isopimarane diterpenes, xylarinorditerpenes A-R (1-18), along with two previously reported compounds, 14α,16-epoxy-18-norisopimar-7-en-4α-ol (19) and the labdane-type diterpene agatadiol (20), were isolated from cultures of the fungicolous fungus Xylaria longipes HFG1018 isolated from the wood-rotting basidiomycete Fomitopsis betulinus. The structure elucidation and relative configuration assignments of 1-18 were accomplished by interpretation of spectroscopic data and through computational methods. The absolute configurations of 1, 4, and 16 were determined by single-crystal X-ray diffraction. Compounds 1-16 possess an 18- or 19-nor-isopimarane skeleton, and compounds 17 and 18 possess an 18,19-dinor-isopimarane skeleton. Compounds 2-5, 9, 14, 19, and 20 showed immunosuppressive activity but were devoid of cytotoxicity against the cell proliferation by concanavalin A-induced T lymphocytes and lipopolysaccharide-induced B lymphocytes, with IC50 values varying from 1.0 to 27.2 μM and from 16.1 to 51.8 μM, respectively.

Two previously undescribed cadinane-type sesquiterpenoids, rigidoporones A and B (1 and 2), along with an undescribed racemic indolizine alkaloid, (±)-rigidoporine A (3), were isolated from the rice fermentation of the wood-decay fungus Rigidoporus microporus. The structures of the compounds were established by extensive spectroscopic methods, including 1D & 2D NMR and HRMS spectroscopic analysis. Compounds 1 and 3 were evaluated for their inhibitory activity on NO production in murine monocytic RAW264.7 macrophages (IC50 > 25 μM).

Ten previously undescribed triterpenoid congeners, namely irpeksolactins A–J, together with eighteen known ones, were isolated from the fruiting bodies of the rainforest-dwelling medicinal fungus Irpex lacteus. The structures of all the isolates were characterized by extensive spectroscopic approaches, including 1D & 2D NMR and MS spectroscopic methods. Irpeksolactin J displayed selective and weak cytotoxicity against the human lung cancer cell line A549 and the human hepatocellular carcinoma cell line SMMC-7721.

Two highly conjugated alkaloids xylaridines A (1) and B (2) were obtained as racemates from the fungus Xylaria longipes. They were resoluted into optically pure enantiomers, respectively. Their structures were determined by extensive spectroscopic analyses, X-ray diffraction, and equivalent circulating density (ECD) calculations. Compound 1 possesses a 5/6/6/5/5 fused ring system with unique 2-azaspiro[4.4]nonane substructure. The hypothesis of biosynthesis pathways for 1 and 2 was proposed.

Two new Tricholoma terpenoids, tricholopardins A and B, were isolated from the fruiting bodies of the basidiomycetes Tricholoma pardinum. Their structures were elucidated by spectroscopic methods, as well as electronic circular dichroism and optical rotatory dispersion calculations. Tricholopardin A potently inhibited nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages with an IC50 of 0.08 μM. Its anti-inflammatory effects on three inflammatory mediators were also evaluated. A plausible biosynthetic pathway for these products is discussed.

Five new triterpenoids, irpeksins A-E (1-5), were isolated from fruiting bodies of the medicinal fungus Irpex lacteus. The structures as well as absolute configurations of the new compounds were established via extensive spectroscopic analysis, computational methods, and Cotton effects. Compounds 1-4 are featured by a scaffold of 1,10- seco- and ring B aromatic eburicane (24-methyllanostane), and compound 5 is characterized by a scaffold of 1,10-9,11- diseco- and ring B aromatic eburicane, which represents unprecedented cleavage patterns in the lanostane family. Compounds 1-5 showed significant inhibitory activity against NO production in LPS-activated RAW 264.7 macrophage cells with IC50 values varying from 2.2 to 19.6 μM.

The phytochemical study of the fruiting bodies of Albatrellus confluens afforded three pairs of new N-Oxidized l -Isoleucine derivatives epimers, confluenines A–F (1–6). The structures of these compounds were deduced using spectroscopic techniques, and the absolute configurations of the compounds were assigned by comparison between experimental and theoretical NMR and ECD data, respectively. Putative biosynthetic pathways toward the oxime, hydroxamate moieties and epimers were discussed. Compounds 5 and 6 exhibited weak antimicrobial activities against Staphylococcus aureus with MIC90 values at 29.3 μg/mL and 56.7 μg/mL, respectively.

Eight undescribed lanostane triterpenoids, pardinols A‒H, along with one previously reported lanostane triterpenoid, namely saponaceol B, were isolated from the fruiting bodies of Tricholoma pardinum. Their structures and stereoconfigurations were established via combination of extensive spectroscopic analyses, alkaline methanolysis method and TDDFT/ECD calculations. Pardinols B and E-H exhibited certain inhibition activities of nitric oxide (NO) production with IC50 value ranging from 5.3 to 14.7 μM, as well as cytotoxicities against human cancer cell-lines.

DJ-1 was recently reported to mediate the cardioprotection of delayed hypoxic preconditioning (DHP) by suppressing hypoxia/reoxygenation (H/R)-induced oxidative stress, but its mechanism against H/R-induced oxidative stress during DHP is not fully elucidated. Here, using the well-established cellular model of DHP, we again found that DHP significantly improved cell viability and reduced lactate dehydrogenase release with concurrently up-regulated DJ-1 protein expression in H9c2 cells subjected to H/R. Importantly, DHP efficiently improved mitochondrial complex I activity following H/R and attenuated H/R-induced mitochondrial reactive oxygen species (ROS) generation and subsequent oxidative stress, as demonstrated by a much smaller decrease in reduced glutathione/oxidized glutathione ratio and a much smaller increase in intracellular ROS and malondialdehyde contents than that observed for the H/R group. However, the aforementioned effects of DHP were antagonized by DJ-1 knockdown with short hairpin RNA but mimicked by DJ-1 overexpression. Intriguingly, pharmacological inhibition of mitochondria complex I with Rotenone attenuated all the protective effects caused by DHP and DJ-1 overexpression, including maintenance of mitochondria complex I and suppression of mitochondrial ROS generation and subsequent oxidative stress. Taken together, this work revealed that preserving mitochondrial complex I activity and subsequently inhibiting mitochondrial ROS generation could be a novel mechanism by which DJ-1 mediates the cardioprotection of DHP against H/R-induced oxidative stress damage.

A scale-up fermentation of the fungus Boreostereum vibrans facilitated the isolation of six new vibralactone biogenesis-associated analogues, namely vibralactamide A (1), vibralactone T (2), 13-O-lactyl vibralactone (3), 10-O-acetyl vibralactone G (4), (11R,12R)- and (11S,12R)-vibradiol (5, 6). Their structures were established via extensive spectroscopic analyses, specific optical rotation comparison, and Snatzke’s method. The biosynthetic pathway for vibralactamide A was postulated. The absolute configuration of vibralactone B was revised by single crystal X-ray diffraction analysis. This work puts the divergent vibralactone biosynthesis pathway one step further and expands the structural diversity of vibralactone-associated compounds. Graphical Abstract Electronic supplementary material The online version of this article (10.1007/s13659-017-0147-5) contains supplementary material, which is available to authorized users.

Seven previously undescribed polyketides, namely childinins A-G, and one previously undescribed 8,14-seco-ergosterol, namely childinasterone A, were obtained from the fruiting bodies of Daldinia childiae. Their structures and absolute configurations were established via extensive spectroscopic analyses, single-crystal X-ray diffraction, and TDDFT/ECD calculations. Childinins A represents the first example of natural product possessing a previously undescribed 6H-naphtho[2,1-c]chromen-6-one scaffold. The single crystal X-ray diffraction of childinasterone A unambiguously determined the absolute configuration of a 8,14-seco-ergosterol skeleton. Childinins A, B, F and G (MIC90 54.9 μg⋅mL-1) showed anti-bacterial activities. Childinasterone A showed significant anti-NO activity (IC50 21.2 μM) and weak activities against SMMC-7721, MCF-7 and SW480 cell lines.

The isotonic substitution of extracellular chloride by gluconate (extracellular Cl--free) has been demonstrated to elicit cardioprotection by attenuating ischaemia/reperfusion-induced elevation of intracellular chloride ion concentration ([Cl-]i). However, the downstream mechanism underlying the cardioprotective effect of extracellular Cl--free is not fully established. Here, it was investigated whether extracellular Cl--free attenuates mitochondrial dysfunction after hypoxia/reoxygenation (H/R) and whether mitochondrial permeability transition pore (mPTP) plays a key role in the extracellular Cl--free cardioprotection. H9c2 cells were incubated with or without Cl--free solution, in which Cl- was replaced with equimolar gluconate, during H/R. The involvement of mPTP was determined with atractyloside (Atr), a specific mPTP opener. The results showed that extracellular Cl--free attenuated H/R-induced the elevation of [Cl-]i, accompanied by increase of cell viability and reduction of lactate dehydrogenase release. Moreover, extracellular Cl--free inhibited mPTP opening, and improved mitochondria function, as indicated by preserved mitochondrial membrane potential and respiratory chain complex activities, decreased mitochondrial reactive oxygen species generation, and increased ATP content. Intriguingly, pharmacologically opening of the mPTP with Atr attenuated all the protective effects caused by extracellular Cl--free, including suppression of mPTP opening, maintenance of mitochondrial membrane potential, and subsequent improvement of mitochondrial function. These results indicated that extracellular Cl--free protects mitochondria from H/R injury in H9c2 cells and inhibition of mPTP opening is a crucial step in mediating the cardioprotection of extracellular Cl--free.

Aurantiadioic acids A (1) and B (2), two new furan-containing polyketides, and aurantoic acid A (3), a new natural product, were isolated from the liquid fermentation of the sika deer dung-derived actinomycete Actinocorallia aurantiaca. The structures of the new compounds were established by extensive spectroscopic methods, including 1D & 2D NMR, HRESIMS spectroscopic analysis. The absolute configuration of 3 was assigned by comparison of the specific optical rotations with the reported derivatives. Biological activity evaluations suggested that compounds 1–3 showed weak inhibition on NO production in the murine monocytic RAW 264.7 macrophages with IC50 values of 35.8, 41.8, 45.2 μM, respectively. Compound 3 showed weak inhibition on influenza A virus (A/PuertoRico/8/1934, H1N1) with an EC50 value of 35.9 μM, and a selective index higher than 13.3.

Resveratrol, a multi-functional phytoalexin, has been well indicated to exert cardioprotective effects by weakening ischemia/reperfusion (I/R) injury, and cell apoptosis is a vital way in I/R injury. SIRT1-p53 pathway has strong significance in regulating cell apoptosis. DJ-1 can directly bind to SIRT1 and stimulate the activity of SIRT1-p53. Therefore, the current study was determined whether Resveratrol attenuates hypoxia/reoxygenation (H/R)-induced cell apoptosis, and whether DJ-1-mediated SIRT1 activation involves in the cardioprotective effects of Resveratrol. The results showed that remarkable decrease in the number of apoptotic cells along with reduction of lactate dehydrogenase release and restoration of cell viability emerged when Resveratrol was applied in the H9c2 cells exposed to H/R. Moreover, Resveratrol increased DJ-1 expression and promoted the interaction of DJ-1 with SIRT1, which further contributed to subsequent restoration of SIRT1 activity and decrease of acetylation level of p53. However, above cardioprotective effects of Resveratrol were abrogated by DJ-1 siRNA and SIRT1 specific inhibitor Sirtinol. In conclusion, the current study demonstrated that Resveratrol suppressed H/R-induced cell apoptosis, which may be conducted by up-regulating DJ-1, and later activating SIRT1 activity and subsequently inhibiting p53 acetylation level in the H9c2 cells.

Eighteen new lanostane-type triterpenoids, namely leucocontextins A-R (1-18) were isolated from the fruiting bodies of Ganoderma leucocontextum. Their structures were established by 1D and 2D NMR data in conjunction with HRESIMS/HREIMS, X-ray single crystal diffraction analysis. Compound 18 exhibited weak cytotoxicity against K562 and MCF-7 cell lines with IC50 of 20-30 μM.

Matsudipeptides A (1) and B (2), two previously undescribed diketopiperazines with peroxy groups, were isolated from the fruiting bodies of the basidiomycete Tricholoma matsutake. These two compounds were featured by unusual scaffolds biogenetically related with cyclic dipeptide. Their structures were elucidated by analysis of spectroscopic data and calculated methods. Both the two compounds were evaluated for their cytotoxicity against five human cancer cell lines (HL-60, SMMC-7721, A549, MCF-7, and SW-480), and their inhibition on acetylcholinesterase.

This study features the isolation and identification of 12 lanostane-type triterpenoids, namely lepiotaprocerins A–L, 1–12, from the fruiting bodies of the Poland-collected edible mushroom Macrolepiota procera. The structures and the absolute configurations of the new compounds were ambiguously established by extensive spectroscopic analyses, ECD calculation, and single-crystal X-ray diffraction analyses. Structurally, lepiotaprocerins A–F, 1–6, are distinguished by the presence of a rare “1-en-1,11-epoxy” moiety which has not been previously described in the lanostane class. Biologically, lepiotaprocerins A–F, 1–6, displayed more significant inhibitions of nitric oxide (NO) production than the positive control L-NG-monomethyl arginine (L-NMMA) (IC50 47.1 μM), and lepiotaprocerins G–L, 7–12, showed various cytotoxicity potencies against a panel of human cancer cell lines. Compound 9 also displayed antitubercular activity against Mycobacterium tuberculosis H37Ra with a minimal inhibitory concentration (MIC...

Four new spiroaxane sesquiterpenes, tramspiroins A-D (1-4), one new rosenonolactone 15,16-acetonide (5), and the known drimane sesquiterpenes isodrimenediol (6) and funatrol D (7) have been isolated from the cultures of Basidiomycete Trametes versicolor. The structures of new compounds were elucidated by means of spectroscopic methods. Compounds 1-7 were investigated for their cytotoxicities against five human cancer cell lines. (C) 2015 Elsevier B.V. All rights reserved.

In this work, a vertical triode consisting of an organic material CuPc and a metal oxide V2O5, was studied by using numerical simulations. The electrical characteristics of the triodes with V2O5 doping concentrations of 1016 – 1018 cm −3 and electrode work functions (WFs) of 4.4 – 5.1 eV were simulated. In addition, the corresponding physical mechanisms were investigated by quantitatively analyzing the energy band diagram, carrier distribution, injection and transports which were difficult to measure and obtain experimentally. The optimal triode performance was obtained for a doping concentration of V2O5 of 2 × 1017 cm −3 and WFs of the emitter and the collector electrodes of 5.1 eV and 4.8 eV, respectively. The simulation results were reasonable when compared with experimental data reported by other groups.

Five new triquinane-type sesquiterpenes, antrodins A-E (1-5) and a new gymnomitrane sesquiterpene, antrodin F (6), together with three known compounds 7-9 were isolated from fermentation of Antrodiella albocinnamomea. Their structures were elucidated through extensive spectroscopic methods including 2D NMR and HRMS analyses. The absolute configurations of 1 and 6 were determined using single-crystal X-ray diffraction analyses. The isolated compounds were investigated for their cytotoxicities against five human cancer cell lines. (C) 2015 Elsevier B.V. All rights reserved.

Two new triterpenoids, (24E)-9α,11α-epoxy-3β-hydroxylanosta-7,24-dien-26-al (1) and (22Z,24Z)-13-hydroxy-3-oxo-14(13 → 12)abeo-lanosta-8,22,24-trien-26,23-olide (2) were isolated from dried fruiting bodies of fungus Ganoderma lucidum. The structures of these two new compounds were elucidated on the basis of extensive spectroscopic analyses. Compound 1 possessed a lanostane skeleton, while compound 2 was based on a rare 14 (13 → 12)abeo-lanostane skeleton with a 26,23-olide moiety. Both of them were evaluated for their antifungal and cytotoxic activities. Neither of them displayed obvious inhibition on Candida albicans and five human cancer cell lines.

Ten new highly oxygenated lanostane triterpenoids, stereinones A–J (1–10), were isolated from the fruiting bodies of the basidiomycete Stereum sp. Compounds 3 and 4 are structurally characterized as intact lanostane-type triterpenoids containing unusual 1,2-diketone functionality at C-11 and C-12, while compound 10 is a 24-methylene-lanostane. The structures of these new compounds were established based on detailed 1D and 2D NMR spectroscopic analyses, along with quantum chemical NMR calculations. All isolates were evaluated for their in vitro cytotoxicities against five human tumor cell lines (including HL-60, A-549, SMMC-7721, MCF-7, and SW480 cell lines). Compound 4 showed moderate cytotoxic activities against tumor cell lines SMMC-7721 and SW480 with IC50 values of 9.1 and 9.8 μM, respectively.

Resveratrol has been demonstrated to have cardioprotective effects by attenuating ischemia/reperfusion (I/R)-induced oxidative stress injury, but its in-depth molecular mechanisms against I/R-induced oxidative stress is not fully elaborated. DJ-1 plays a role in maintenance of mitochondrial complex I activity and is closely associated with oxidative stress. Therefore, this study sought to determine the contribution of DJ-1-mediated maintenance of mitochondrial complex I activity to the anti-oxidative stress effect of Resveratrol in the H9c2 cardiomyocytes subjected to hypoxia/reoxygenation (H/R). The results showed that Resveratrol significantly attenuated the H/R-induced viability loss and lactate dehydrogenase leakage, accompanied by decreases in intracellular reactive oxygen species (ROS) and malondialdehyde contents and increases in the reduced glutathione/oxidized glutathione ratio. Furthermore, Resveratrol increased the expression and mitochondrial translocation of DJ-1 and promoted the direct binding of DJ-1 with complex I subunits ND1 and NDUFS4, which in turn improved mitochondrial complex I activity and inhibited mitochondria-derived ROS production after H/R. Intriguingly, the anti-oxidative stress effect of Resveratrol could be partially blocked by DJ-1 siRNA and Complex I inhibitor Rotenone, respectively. Conclusively, these results indicated that DJ-1 is necessary for Resveratrol-mediated cardioprotective effects against H/R-induced oxidative stress damage, at least in part, through preserving mitochondrial complex I activity, and subsequently decreasing mitochondrial ROS generation.

Molecular identification suggested an edible mushroom, which was previously named as Craterellus odoratus should be revised as Montagnula donacina. A chemical re-investigation of the culture broth of this fungus resulted in the isolation of four rare tetracyclic bergamotane-type sesquiterpenoids, namely donacinolides A and B, donacinoic acids A and B, and three cadinane-type ones, namely donacinols A–C and a meroterpenoid (Z)-4-hydroxy-3-(3-hydroxy-3-methylbut-1-en-1-yl)benzoic acid. Their structures were established via extensive spectroscopic methods, single crystal X-ray diffraction analysis, and computational methods. (Z)-4-Hydroxy-3-(3-hydroxy-3-methylbut-1-en-1-yl)benzoic acid showed antibacterial activity against Staphylococcus aureus.

Two new cytochalsians, multirostratin A (1) and 20-oxo-deoxaphomin (2), together with five known analogues (3-7), were obtained from the endophytic fungus Phoma multirostrata EA-12. The structures of 1 and 2 were elucidated by MS and 1D- and 2D-NMR spectroscopic data analyses, as well as by comparison of data with those of analogues reported in the literature. Compounds 1 and 2 showed moderate cytotoxicity against five tumor cell lines (HL-60, A-549, SMMC-7721, MCF-7 and SW-480).

An acquired resistance to platinum-based drugs has emerged as a significant impediment to effective ovarian cancer therapy. The present study explored the anticancer mechanisms of triptolide (TPL) in SKOV3PT platinum-resistant human ovarian cancer cells and observed that TPL activated caspase 3 and induced the dose-dependent apoptosis of the SKOV3PT cells. Furthermore, TPL inhibited complex I of the mitochondrial respiratory chain (MRC) followed by an increase of reactive oxygen species (ROS), which further inhibited nuclear factor (NF)-κB activation and resulted in the downregulation of anti-apoptotic proteins, Bcl-2 and X-linked inhibitor of apoptosis protein (XIAP). Notably, the pre-treatment with N-acetyl-L-cysteine (NAC) abolished the TPL-induced ROS generation, NF-κB inhibition and cell apoptosis, but did not affect the inhibitory effect of TPL on complex I activity. These results suggested that TPL negatively regulated the NF-κB pathway through mitochondria-derived ROS accumulation, promoting the apoptosis of the SKOV3PT cells. Furthermore, TPL synergistically enhanced the cytotoxicity of cisplatin against platinum-resistant ovarian cancer cells. Collectively, these findings suggest that TPL is able to overcome chemoresistance and that it may be an effective treatment for platinum-resistant ovarian cancer, either alone or as an adjuvant therapy.

It has been well accepted that increased reactive oxygen species (ROS) and the subsequent oxidative stress is one of the major causes of ischemia/reperfusion (I/R) injury. DJ-1 protein, as a multifunctional intracellular protein, plays an important role in regulating cell survival and antioxidant stress. Here, we wondered whether DJ-1 overexpression attenuates simulated ischemia/reperfusion (sI/R)-induced oxidative stress. A rat cDNA encoding DJ-1 was inserted into a mammalian expression vector. After introduction of this construct into H9c2 myocytes, stable clones were obtained. Western blot analysis of the derived clones showed a 2.6-fold increase in DJ-1 protein expressing. Subsequently, the DJ-1 gene-transfected and control H9c2 cells were subjected to sI/R, and then cell viability, lactate dehydrogenase, malondialdehyde, intracellular ROS and antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) were measured appropriately. The results showed that stable overexpression of DJ-1 efficiently attenuated sI/R-induced viability loss and lactate dehydrogenase leakage. Additionally, stable overexpression of DJ-1 inhibited sI/R-induced the elevation of ROS and MDA contents followed by the increase of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) activities and expression. Our data indicate that overexpression of DJ-1 attenuates ROS generation, enhances the cellular antioxidant capacity and prevents sI/R-induced oxidative stress, revealing a novel mechanism of cardioprotection. Importantly, DJ-1 overexpression may be an important part of a protective strategy against ischemia/reperfusion injury. Copyright © 2012 John Wiley & Sons, Ltd.

We have shown recently that sasanquasaponin (SQS) can inhibit ischemia/reperfusion-induced elevation of intracellular Cl–concentration ([Cl–]i) and elicit cardioprotection by up-regulating anion exchanger 3 (AE3) expression. In the present study, we futher analysed the intracellular signal transduction pathways by which SQS up-regulates AE3expression and elicits cardioprotection. Cardiomyocytes were incubated for 24 h with or without 10 µmol/L SQS, followed by simulated ischemia/reperfusion (sI/R). NO formation, Ras activity, and extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation were measured appropriately. We showed that SQS pretreatment efficiently attenuated viability loss and lactate dehydrogenase leakage induced by sI/R in cardiomyocytes. Moreover, SQS induced NO production and promoted Ras activation, which futher promoted extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation. These effects were paralleled by an increase in AE3expression. However, when the cardiomyocytes were treated with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide (c-PTIO; an NO scavenger), S-trans-trans-farnesylthiosalicylic acid (FTS) (a Ras inhibitor), U0126 (an ERK1/2 inhibitor), respectively, the increase in AE3expression occurring during SQS pretreatment was almost completely abolished and, as a result, SQS-induced cardioprotection was prevented. Our findings indicate that SQS might up-regulate AE3expression through NO/Ras/ERK1/2 signal pathway to elicit cardioprotection in cultured cardiomyocytes.

Excess apoptosis of endothelial cells (EC) plays crucial roles in the onset and progression of vasculopathy in diabetes mellitus. Anion exchanger-2 (AE2) might be involved in the vasculopathy. However, little is known about the molecular mechanisms that AE2 mediated the apoptosis of EC. The purpose of this study was to explore the role of AE2 in the apoptosis of HUVECs induced by high glucose (HG) and its possible mechanisms. First, HUVECs were exposed to different glucose concentrations (5.5, 17.8, 35.6, 71.2 and 142.4 mmol/l, respectively, pH = 7.40) for different time points (12, 24, 48, 72, 120, and 168 h, respectively). Intracellular Cl(-) concentration ([Cl(-)]i), AE2 expression and the apoptosis were assayed. Then, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), Cl(-)-free media or specific RNA interference (RNAi) for AE2 was used to confirm whether AE2 could mediate the apoptosis induced by HG. Finally, the mechanisms of the AE2-mediated apoptosis were investigated by detecting mitochondrial permeability transition pore (mPTP, DeltaPsim) openings, reactive oxygen species (ROS) levels and Caspase-3 activity. We found that HG upregulated the AE2 expression and activity, increased [Cl(-)]i and induced the apoptosis in a time- and concentration-dependent manner. The apoptosis of HUVECs by HG was possibly mediated by AE2 through an mPTP-ROS-Caspase-3 dependent pathway. These findings suggested that AE2 was likely to be a glucose-sensitive transmembrane transporter and a novel potential therapeutic target for diabetic vasculopathy.

Development of intracellular calcium overload is an important pathophysiological factor in myocardial ischemia/reperfusion or anoxia/reoxygenation injury. Recent studies have shown that Sodium Ferulate (SF) stimulates nitric oxide (NO) production and exerts a cardioprotective effect in the ischemia-reperfused heart. However, it has not been determined whether the cardioprotection of SF is associated with suppression of Ca(2+) overload via NO/cyclic GMP (cGMP)/cGMP-dependent protein kinase (PKG) pathway. In this work, after cardiomyocytes were incubated with 100, 200, 400, or 800 microM SF for 3 h, anoxia/reoxygenation injury was induced and intracellular Ca(2+) concentration, NO synthase (NOS) activity, guanylate cyclase activity, NO, and cGMP formation were measured appropriately. The results showed that treatment with SF concentration-dependently inhibited calcium overload induced by anoxia/reoxygenation. We also demonstrated that SF (100-800 microM) concentration dependently enhanced NO and cGMP formation through increasing NOS activity and guanylate cyclase activity in the cardiomyocytes. On the contrary, inhibition of calcium overload by SF was markedly attenuated by addition of an NOS inhibitor, an NO scavenger, an soluble guanylate cyclase inhibitor, and a PKG inhibitor: N(G)-nitro-l-arginine methyl ester (L-NAME, 100 microM), 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazole-1-oxyl-3-oxide (c-PTIO, 1.0 microM), 1H-[1, 2, 4] oxadiazolo [4, 3-alpha] quinoxalin-1-one (ODQ, 20 microM) and KT5823 (0.2 microM), respectively. Our findings indicate that SF significantly attenuates anoxia/reoxygenation-induced Ca(2+) overload and improves cell survival in cultured cardiomyocytes through NO/cGMP/PKG signal pathway.

Reactive oxygen species can play an important role in the pathogenesis of anoxia-reoxygenation injury. Sasanquasaponin (SQS) is a biologically active ingredient extracted from the Chinese medicinal plant Camellia oleifera Abel. Some studies have shown that SQS possesses potent antioxidant activities. However, it has not been elucidated whether SQS diminishes reactive oxygen species stress induced by anoxia-reoxygenation injury in cardiomyocytes. In this work, neonatal rat cardiomyocytes pretreated with the test compound were subjected to anoxia-reoxygenation. The extent of cellular damage was accessed by cell viability and the amount of released lactate dehydrogenase (LDH). Superoxide dismutase, catalase and glutathione peroxidase activities, reduced (GSH) and oxidized glutathione (GSSG) levels, and malondialdehyde contents were measured by a colorimetric method. The levels of intracellular reactive oxygen species and calcium were determined by flow cytometry. The results showed that SQS reduced LDH release and increased cell viability in a dose-dependent manner up to 10 microM and concomitantly decreased malondialdehyde and GSSG contents, while significantly increased GSH contents and the activities of superoxide dismutase, catalase and glutathione peroxidase. Moreover, treatment with SQS decreased intracellular reactive oxygen species levels and alleviated calcium accumulation in cardiomyocytes undergoing anoxia-reoxygenation. It is suggested that SQS could protect cardiomyocytes against oxidative stress induced by anoxia-reoxygenation by attenuating reactive oxygen species generation and increasing activities of endogenous antioxidants.

The protective effects of sasanquasaponin, an effective compound from Chinese traditional herbs, on ischaemia and reperfusion injury in mouse hearts have been suggested through modulation of intracellular Cl(-) homeostasis. The effects of sasanquasaponin on injury of endothelial cells, however, induced by anoxia and reoxygenation remain unknown. Therefore, the present study attempted to observe the effects of sasanquasaponin on anoxia and reoxygenation injury in endothelial cells and investigate its putative mechanisms. Human umbilical vein endothelial cells (HUVECs) were exposed to normoxia or anoxia and reoxygenation in the absence or presence of sasanquasaponin (10.0, 1.0 and 0.1 micromol/l). Lactate dehydrogenase activity was determined in cultured HUVECs supernatant, and malondialdehyde content, superoxide dismutase and glutathione peroxidase activities were measured in HUVECs by a colorimetric method. Neutrophil adhesion to HUVECs was assayed colorimetrically. The levels of intercellular adhesion molecule-1 and tumour necrosis factor-alpha were detected. The activity of nuclear factor kappa B was determined by flow cytometry. The results show that sasanquasaponin decreased the lactate dehydrogenase activity and malondialdehyde contents, and inhibited the neutrophil adhesion to HUVECs; sasanquasaponin, moreover, inhibited nuclear factor kappa B transnuclear activity, lowered tumour necrosis factor-alpha and intercellular adhesion molecule-1 expression levels. On the other hand, sasanquasaponin increased the mitochondrial superoxide dismutase and glutathione peroxidase activities. It is suggested that sasanquasaponin could protect HUVECs against anoxia and reoxygenation injury, and the protective mechanisms appear to be related to anti-lipoperoxidation and anti-adhesion.

The novel compound, 3-(E)-ferrocenyl-vinyl-N-hexylcarbazole (FVHC) was first synthesized and fully characterized by elemental analysis, IR, 1H-NMR, single-crystal X-ray diffraction, ultraviolet (UV) absorption, cyclic voltammograms (CV) and optical limiting (OL) measurements. The result of single crystal X-ray diffraction for the compound reveals that the ferrocenyl and carbazole groups are approximately coplanar, and bridged by double-bond with E configuration, showing that there is a well-delocalized π-electron system in the molecule. The electrochemical investigation indicated that the electron in the FVHC may partially be delocalized over the π-conjugated system and CT process in functionalized carbazole systems. Besides, the compound exhibited strong UV absorption and large optical limiting effect, indicating promising potential applications as useful OL materials.

A variety of novel natural products with significant bioactivities are produced by the basidiomycete Boreostereum vibrans. In the present study, we describe 16 novel natural oximes and oxime esters with a vibralactone backbone, vibralactoximes, which were isolated from the scale‐up fermentation broth of B. vibrans. Their structures were determined through extensive spectroscopic analyses. These compounds represent the first oxime esters from nature. The hypothetical biosynthetic pathway of these compounds was also proposed. Seven compounds exhibited significant pancreatic lipase inhibitory activity, while ten compounds exhibited cytotoxicities against five human cancer cell lines (HL‐60, SMMC‐7721, A‐549, MCF‐7, and SW480), with IC50 values comparable with those of cisplatin.

1. Burn-induced myocardial injuries can be acute due to loss of body fluid and blood redistribution, and subacute due to pathogenic toxins of infecting bacteria. The goal of this study was to examine expression of 14-3-3 in the injured myocardium. 2. Myocardial injury models were created in vivo by subjecting rats to severe burn and administration of lipopolysaccharide. RT-PCR and Western blotting were employed to assess the expression of 14-3-3 proteins and messenger ribonucleic acid (mRNA) for 14-3-3eta and gamma in the myocardium, respectively. 3. In the two models, we found that 14-3-3 proteins were induced in a time-dependent fashion. Such a change is at least in part attributed to increases in mRNAs for 14-3-3gamma and eta. In contrast to 14-3-3xi, whose mRNA was not detectable in the heart, mRNA for 14-3-3gamma was found significantly elevated between 24-48 h after burn. 14-3-3eta mRNA exhibited a marked increase at 3 h continuing to 12 h and then decreased nearly to a normal level after 48 h. In lipopolysaccharide-treated intact rats, 14-3-3gamma mRNA in myocardium showed a significant increase, reaching a peak at 4 h, followed by a decrease at 6 h. In contrast, 14-3-3eta mRNA had a slight increase without significance. 4. Our results suggest that 14-3-3 may play a role in both acute and subacute (postburn infectious) phases of severe burn.

A new Schiff base 4-[N-hydroxyethyl-N-(methyl)amino]benzaldehyde S-methyl dithiocarbazate (HL, where H is a dissociable proton) and the ruthenium complex [Ru(bpy)2L]PF6 (bpy = 2,2′-bipyridine) have been synthesized. The structural determinations of the ligand and its ruthenium complex, by X-ray crystallography, show that the ligand is coordinated as a monoanionic bidentate N, S-donor, forming a four-member chelate ring with a bite angle of 65.91°. The complex shows intense MLCT transitions in the visible region. Fluorescent and electrochemical properties have been also studied. The complex in DMF solution exhibited a strong two-photon absorption (t.p.a.) at 532 nm nanosecond laser pulses. The t.p.a. coefficient β, t.p.a. cross-section σ and the third-order optical nonlinearity χ(3) of the complex and the ligand have been determined by the Z-scan technique.

The thermal stability of the cellulose synthase complex of Acetobacter xylinum has been analyzed in terms of enzyme activity loss as well as detection of its two major components (83 kDa and 93 kDa polypeptides) in polyacrylamide gels under different electrophoretic sample treatment conditions. The cellulose synthase complex intrinsically is a thermally unstable enzyme and quickly loses its in vitro activity beyond 35° C. The 83 kDa polypeptide has been found to be more labile than the 93 kDa polypeptide. When boiled in lithium dodecyl sulfate (LDS) buffer, the 83 kDa polypeptide is destroyed through peptide hydrolysis while the 93 kDa polypeptide remains uncleaved. The 83 kDa polypeptide is destroyed in LDS buffer at elevated temperatures beyond 55° C. When boiled in the absence of LDS buffer, the 83 kDa polypeptide is completely aggregated, while the 93 kDa polypeptide is only partially aggregated. In the absence of LDS buffer, the complete thermal aggregation of the 83 kDa polypeptide occurs at elevated temperatures beyond 85° C. The aggregation process has been quantitatively analyzed by a newly‐introduced quantitative index, Td (the temperature at which half the quantity of 83 kDa polypeptide disappears due to aggregation). The Td determined for the 83 kDa polypeptide in the product‐entrapped fraction is 48° C.

Antibodies (anti-83 and anti-93) against the cellulose synthase complex from A. xylinum ATCC 53582 have been employed to study the evolutionary conservation of this enzyme complex among various A. xylinum strains, selected species of other cellulose- producing bacteria, algae, and vascular plants. Of the 18 A. xylinum strains examined, the 83 Kd polypeptide clearly is detected only in 4 strains while the 93 Kd polypeptide is observed in all 18 strains. Assuming that the revised acsAB gene (Saxena et al., 1994) encoding the 83 and 93 Kd polypeptides as a single polypeptide holds true for all A. xylinum strains, it is proposed that the cellulose synthase is conserved in A. xylinum but with varying degrees of homology. An unknown regulatory mechanism causing the degradation of the 83 Kd polypeptide in response to agitated culturing conditions has been suggested to explain the absence of the 83 Kd polypeptide in most of the Acetobacter strains examined. A. xylinum cellulose synthase appears to be conserved in phylogenetically related Rhizobium and Agrobacterium species, but not in algae and plants.

An immunochemical method was used to analyse the 83 and 93 Kd polypeptides of cellulose synthase from Acetobacter xylinum.Polyclonal antibodies were raised against the LDS-PAGE-fractionated 83 and 93 Kd polypeptides isolated from A. xylinum.Using these antibodies, the 83 and 93 Kd polypeptides were localized in the different fractions during purification of cellulose synthase, and the ratio of these two polypeptides was determined to be 1∶1. A differential solubilization of the 83 and 93 Kd polypeptides from the cell strongly suggested that the mechanism by which these two polypeptides originate from a single acsAB gene product (Saxena et al.,1994) must be via a post-translational cleavage. The results of trypsin treatment of the membrane fraction used in the purification of cellulose synthase were analysed to determine the fate of these two polypeptides and their relationship to the enzyme activity.

Recent studies have shown that the cardioprotection of sasanquasaponin (SQS) against ischemia/reperfusion injury is related to inhibiting ischemia/reperfusion-induced elevation of intracellular Cl(-) concentration ([Cl(-) ](i)). However, the mechanism of inhibition remains unclear. Anion exchanger 3 (AE(3)) is an important regulatory protein for [Cl(-)](i). This study investigated whether AE(3) plays the critical role in the inhibitory effect of SQS on elevation of [Cl(-)](i) induced by ischemia/reperfusion and mediates the cardioprotection of SQS in H9c2 cells. Normal and AE(3) -knockdown H9c2 cells were incubated for 24 h with or without various concentrations of SQS (0.1, 1, or 10 µM) followed by simulated ischemia/reperfusion (sI/R). AE(3) expression was detected by Western blot. Flow cytometer analysis was employed to determine [Cl(-)](i,) [Ca(2+)](i) , reactive oxygen species (ROS) production, and cell apoptosis. The results showed that SQS pretreatment concentration-dependently attenuated sI/R-induced viability loss and lactate dehydrogenase leakage in normal H9c2 cells. Additionally, SQS concentration-dependently up-regulated AE(3) protein expression, and inhibited sI/R-induced the elevation of [Cl(-)](i) followed by the attenuation of Ca(2+) overload, ROS production, and cell apoptosis. However, the dose-dependent cardioprotection induced by SQS was abolished in AE(3) -knockdown H9c2 cells, and the inhibitory effects of SQS on [Cl(-)](i), Ca(2+) overload, ROS production, and cell apoptosis were also reversed. Our data indicate that AE(3) mediates the cardioprotective effect of SQS against sI/R injury. Importantly, AE(3) is required for SQS to inhibit sI/R-induced elevation of [Cl(-)](i), which subsequently inhibited sI/R-induced Ca(2+) overload, ROS production, and cell apoptosis.

Sasanquasaponin (SQS) is an effective component of Camellia oleifera Abel. This study was designed to investigate the cardioprotective effect of SQS against ischemia-reperfusion (I/R) injury and the possible mechanism in isolated rat hearts. These hearts were pretreated by SQS only or SQS and HOE140 in different groups, and then subjected to I/R injury. Hemodynamic parameters, oxidative injury, and NO level were measured. The results showed that SQS preconditioning could decrease the incidences of arrhythmias and improve the heart functions. In addition, SQS preconditioning could protect isolated I/R injured heart against lipid peroxidation, as evidenced by increases in SOD and GSH-Px activity, and by decreases in contents of MDA, ROS generation. However, HOE140 treatment reversed all these indexes. NO production was significantly decreased after a treatment with HOE140. So we can propose that SQS preconditioning could induce the cardioprotective effects and the possible mechanism was that the activation of bradykinin-NO system by SQS preconditioning had an inhibition effect on ROS generation in isolated heart.

The purpose of this study was to investigate the effects of sasanquasaponin (SQS) on ICAM-1 expression and capillary permeability induced by burns in rats. Male adult Sprague-Dawley (SD) rats were subjected to burns in the presence or absence of SQS, and then intravenously injected with Evans blue (60.0 mg/kg body weight). The levels of soluble ICAM-1 (sICAM-1) in sera were assayed using ELISA and the expression levels of transmembrane ICAM-1 (mICAM-1) in aorta were determined by Western blots and ICAM-1 mRNA levels were measured using semi-quantification RT-PCR. The capillary permeability was determined spectrophotometrically. The results showed that SQS markedly lowered the levels of sICAM-1 in sera, and considerably inhibited the over-expression as well as transcription of mICAM-1 in rat aorta. In addition, SQS dramatically inhibited the enhancement of dermal capillary permeability induced by burns in a dose-dependent manner. These results suggest that SQS, developed from Chinese traditional herbs, might be effective in decreasing inflammation induced by burns.

In this work, a technology computer-aided design (TCAD) device model based on an fabricated amorphous InGaZnO thin-film transistor (a-IGZO TFT) was established to study the correlation between carrier concentration distribution, current-voltage (I-V) and capacitance-voltage (C-V) characteristics of a-IGZO TFTs. The equilibrium carrier concentration of the a-IGZO layer influenced by defect states, interface fixed charges, gate and S/D electrodes were studied systematically and quantitatively. The a-IGZO thickness was varied from 10 nm to 140 nm. The doping concentration in the bulk a-IGZO layer and source/drain (S/D) contact regions were changed from 10 10 cm -3 to 10 20 cm -3 . The physical mechanisms underlying the I-V and C-V variation caused by above-mentioned parameters were explored by analyzing the energy band diagram and carrier concentration distribution in the a-IGZO layer. The total number of electrons in the channel region of the TFT was calculated by numeric integration for further investigation of its correlation with the a-IGZO thickness, I-V, and C-V characteristics of the a-IGZO TFTs.

The unusual fused β-lactone vibralactone was isolated from cultures of the basidiomycete Boreostereum vibrans and has been shown to significantly inhibit pancreatic lipase. In this study, a structure-based lead optimization of vibralactone resulted in three series of 104 analogs, among which compound C1 exhibited the most potent inhibition of pancreatic lipase, with an IC50 value of 14 nM. This activity is more than 3000-fold higher than that of vibralactone. The effect of compound C1 on obesity was investigated using high-fat diet (HFD)-induced C57BL/6 J obese mice. Treatment with compound C1 at a dose of 100 mg/kg significantly decreased HFD-induced obesity, primarily through the improvement of metabolic parameters, such as triglyceride levels. Electronic supplementary material The online version of this article (doi:10.1007/s13659-015-0062-6) contains supplementary material, which is available to authorized users.

Six new lanostane-type triterpenoids, namely leucocontextins S–X (1–6), together with twelve known compounds, were isolated from the fruiting bodies of Ganoderma leucocontextum. Their structures were established by MS and NMR data. Graphical Abstract Electronic supplementary material The online version of this article (doi:10.1007/s13659-016-0089-3) contains supplementary material, which is available to authorized users.