Leukotrienes Target F-actin/Cofilin-1 to Enhance Alveolar Macrophage Anti-fungal Activity

Candida albicans is the most common opportunistic fungal pathogen and causes local and systemic disease in immunocompromised patients. Alveolar macrophages (AMs) are pivotal for the clearance of C. albicans from the lung. Activated AMs secrete 5-lipoxygenase-derived leukotrienes (LTs), which in turn enhance phagocytosis and microbicidal activity against a diverse array of pathogens. Our aim was to investigate the role of LTB(4) and LTD(4) in AM antimicrobial functions against C. albicans and the signaling pathways involved. Pharmacologic and genetic inhibition of LT biosynthesis as well as receptor antagonism reduced phagocytosis of C. albicans when compared with untreated or WT controls. Conversely, exogenous LTs of both classes augmented base-line C. albicans phagocytosis by AMs. Although LTB(4) enhanced mainly mannose receptor-dependent fungal ingestion, LTD(4) enhanced mainly dectin-1 receptor-mediated phagocytosis. LT enhancement of yeast ingestion was dependent on protein kinase C-delta (PKC delta) and PI3K but not PKC alpha and MAPK activation. Both LTs reduced activation of cofilin-1, whereas they enhanced total cellular F-actin; however, LTB(4) accomplished this through the activation of LIM kinases (LIMKs) 1 and 2, whereas LTD(4) did so exclusively via LIMK-2. Finally, both exogenous LTB(4) and LTD(4) enhanced AM fungicidal activity in an NADPH oxidase-dependent manner. Our data identify LTB(4) and LTD(4) as key mediators of innate immunity against C. albicans, which act by both distinct and conserved signaling mechanisms to enhance multiple antimicrobial functions of AMs.

Circadian rhythm of anti-fungal prenylated chromene in leaves of Piper aduncum

Leaves of Piper aduncum accumulate the anti-fungal chromenes methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (1) and methyl 2,2-dimethyl-8-(3'-methyl-2'-butenyl)-2H-1-chromene-6-carboxylate (2). The enzymatic formation of 2 from dimethylallyl diphosphate and I was investigated using cell-free extracts of the title plant. An HPLC assay for the prenylation reaction was developed and the enzyme activity measured in the protein extracts. The prenyltransferase that catalyses the transfer of the dimethylallyl group to C-2' of 1 was soluble and required dimethylallyl diphosphate as the prenyl donor. In the leaves, the biosynthesis of the prenylated chromene 2 was time-regulated and prenyltransferase activity depended upon circadian variation. Preliminary characterisation and purification experiments on the prenyltransferase from P. aduncum have been performed. Copyright (C) 2005 John Wiley & Sons, Ltd.

EVALUATION OF THE ANTI-FUNGAL PROPERTIES OF EXTRACTS OF Daniella oliveri

The in vitro anti-fungal activity of leaf and stem bark of Daniella oliveri Rolfe was investigated against selected yeasts and moulds including dermatophytes. Water and methanol were used to extract the powdered leaf and stem bark using cold infusion. Antimicrobial activity was assessed by agar-well diffusion. Phytochemical analysis was carried out using standard procedures. The plant extracts were active against the test organisms at concentrations ranging from 3.125-100 mg/mL. The methanol extracts were more active than the aqueous extracts with the highest inhibition against the yeasts, Candida albicans and Candida krusei (MIC values of 3.125 mg/mL and 6.25 mg/mL respectively). Epidermophyton floccosum and Trichophyton interdigitale were the least inhibited of all the fungal strains. Phytochemical screening revealed the presence of tannins, anthraquinones, flavonoids, cardiac glycosides, alkaloids and saponins. The anti-fungal activity of Daniella oliveri as shown in this study indicates that the plant has the potential of utilisation in the development of chemotherapeutic agents for the treatment of relevant fungal infections.

Anti-Trichophyton Activity of Protocatechuates and Their Synergism with Fluconazole

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

In vitro anti-Candida activity of Glycyrrhiza glabra L.

The severity and frequency of opportunistic fungal infections still growing, concomitantly to the increasing rates of antimicrobial drug’s resistance. Natural matrices have been used over years due to its multitude of health benefits, including antifungal potential. Thus, the present work aims to evaluate the anti-Candida potential of the phenolic extract and individual phenolic compounds of Glycyrrhiza glabra L. (licorice), by disc diffusion assay, followed by determination of the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) for both planktonic cells and biofilms. Licorice extract evidenced inhibitory potential against the nineteen tested Candida strains, but no pronounced effect was observed by testing the most abundant individual phenolic compounds. Candida tropicalis strains were the most sensible, followed by Candida glabrata, Candida parapsilosis and, then, Candida albicans. Lower MIC and MFC values were achieved to C. glabrata and C. tropicalis, which confirms its susceptibility to licorice extract; however, for C. tropicalis strains a higher variability was observed. Anti-biofilm potential was also achieved, being most evident in some C. glabrata and C. tropicalis strains. In general, a twice concentration of the MIC was necessary for planktonic cells to obtain a similar potential to that one observed for biofilms. Thus, an upcoming approach for new antifungal agents, more effective and safer than the current ones, is stablished; notwithstanding, further studies are necessary in order to understand its mechanism of action, as also to assess kinetic parameters.

Anti-cancer activity of zoledronic acid in breast cancer

Background: Zoledronic acid is used to prevent the bone loss associated with antioestrogen treatments in subjects with breast cancer. Preclinical studies suggest that zoledronic acid may have anticancer activity in its own right. This anticancer possibility with zoledronic acid has not been investigated extensively in clinical trials. Objectives/methods: This evaluation is of a large clinical trial that investigated the effect of zoledronic acid on cancer outcomes in premenopausal women with breast cancer. Results: The trial showed that after 4 years, 94.0% of subjects who were treated with zoledronic acid were disease-free compared with 90.8% of those not treated with zoledronic acid. Recurrence survival was a secondary end point; this occurred in 94.0% with, and 90.9% without, zoledronic acid treatment. Conclusions: Zoledronic acid does have anticancer activity in premenopausal women with cancer.

Isolation of bioactive compounds that relate to the anti-platelet activity of Cymbopogon ambiguus

Infusions and decoctions of Cymbopogon ambiguus have been used traditionally in Australia for the treatment of headache, chest infections and muscle cramps. The aim of the present study was to screen and identify bioactive compounds from C. ambiguus that could explain this plant's anti-headache activity. A dichloromethane extract of C. ambiguus was identified as having activity in adenosine-diphosphate-induced human platelet aggregation and serotonin-release inhibition bioassays. Subsequent fractionation of this extract led to the isolation of four phenylpropenoids, eugenol, elemicin, Eugenol methylether and trans-isoelemicin. While both Eugenol and elemicin exhibited dose-dependent inhibition of ADP-induced human platelet serotonin release, only eugenol displayed potent inhibitory activity with an IC(50) value of 46.6 microM, in comparison to aspirin, with an IC(50) value of 46.1 microM. These findings provide evidence to support the therapeutic efficacy of C. ambiguus in the non-conventional treatment of Headache and Inflammatory conditions.

Anti-staphylococcal activity of C-methyl flavanones from propolis of Australian stingless bees (Tetragonula carbonaria) and fruit resins of Corymbia torelliana (Myrtaceae)

Propolis of Australian stingless bees (Tetragonula carbonaria, Meliponini) originating from Corymbia torelliana (Myrtaceae) fruit resins was tested for its antimicrobial activities as well as its flavonoid contents. This study aimed at the isolation, structural elucidation and antibacterial testing of flavanones of C. torelliana fruit resins that are incorporated into stingless bee propolis. Flavanones of this study were elucidated by spectroscopic and spectrometric methods including UV, 1D and 2D NMR, EI-MS, ESI-MS and HR-MS. The results indicated known C-methylated flavanones namely, 1 (2S)-cryptostrobin, its regioisomer 2 (2S)- stroboponin, 3 (2S)- cryptostrobin 7-methyl ether, and 6 (2S)- desmethoxymatteucinol, and known flavanones 4 (2S)- pinostrobin and 5 (2S)- pinocembrin as markers for C. torelliana fruit resins and one propolis type. Ethanolic preparations of propolis were shown to be active against Staphylococcus aureus (ATCC 25923) and to a lesser extent against Pseudomonas aeruginosa (ATCC 27853). C. torelliana flavanones inhibited the growth of S. aureus therefore contributing to the antibacterial effects observed for Australian stingless bee propolis extracts.

DC-SIGN and alpha 2,6-sialylated IgG Fc interaction is dispensable for the anti-inflammatory activity of IVIg on human dendritic cells

Intravenous immunoglobulin (IVIg) is widely used to treat autoimmune diseases. Several mutually nonexclusive mechanisms are proposed to explain the beneficial effects of IVIg in patients (1, 2). Lately, Ravetch and colleagues (3) demonstrate that anti-inflammatory activity of IVIg is mediated mainly by antibodies that contain terminal _2,6-sialic acid linkages at the Asn297-linked glycan of Fc region.

Anti-obese activity of Butea monosperma (Lam) bark extract in experimentally induced obese rats

To study the efficacy of ethanolic extract of B. monosperma bark in cafeteria and atherogenic diet fed rats and monosodium glutamate (MSG) obese rats, different doses (200, 400 and 800 mg/kg) of ethanolic extract of B. monosperma bark showed dose dependent decrease in body weight, daily food intake, glucose, lipids, internal organs' weight and fat pad weight in cafeteria and atherogenic diet fed rats and monosodium glutamate obese rats. The results suggested that B. monosperma has significant anti-obese activity.

DNA targeting polyaza macrobicyclic dizinc(II) complexes promoting high in vitro caspase dependent anti-proliferative activity against human carcinoma cancer cells

A series of macrobicyclic dizinc(II) complexes Zn2L1-2B](ClO4)(4) (1-6) have been synthesized and characterized (L1-2 are polyaza macrobicyclic binucleating ligands, and B is the N,N-donor heterocyclic base (viz. 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen)). The DNA and protein binding, DNA hydrolysis and anticancer activity of these complexes were investigated. The interactions of complexes 1-6 with calf thymus DNA were studied by spectroscopic techniques, including absorption, fluorescence and CD spectroscopy. The DNA binding constant values of the complexes were found to range from 2.80 x 10(5) to 5.25 x 10(5) M-1, and the binding affinities are in the following order: 3 > 6 > 2 > 5 > 1 > 4. All the dizinc(II) complexes 1-6 are found to effectively promote the hydrolytic cleavage of plasmid pBR322 DNA under anaerobic and aerobic conditions. Kinetic data for DNA hydrolysis promoted by 3 and 6 under physiological conditions give observed rate constants (k(obs)) of 5.56 +/- 0.1 and 5.12 +/- 0.2 h(-1), respectively, showing a 10(7)-fold rate acceleration over the uncatalyzed reaction of dsDNA. Remarkably, the macrobicyclic dizinc(II) complexes 1-6 bind and cleave bovine serum albumin (BSA), and effectively promote the caspase-3 and caspase-9 dependent deaths of HeLa and BeWo cancer cells. The cytotoxicity of the complexes was further confirmed by lactate dehydrogenase enzyme levels in cancer cell lysate and content media.

Cobalt(II), Nickel(II) and Copper(II) complexes of a tetradentate Schiff base as photosensitizers: Quantum yield of O-1(2) generation and its promising role in anti-tumor activity

In the present investigation, a Schiff base N'(1),N'(3)-bis(E)-(5-bromo-2-hydroxyphenyl)methylidene]benzene-1,3-d icarbohydrazide and its metal complexes have been synthesized and characterized. The DNA-binding studies were performed using absorption spectroscopy, emission spectra, viscosity measurements and thermal denatuaration studies. The experimental evidence indicated that, the Co(II), Ni(II) and Cu(II) complexes interact with calf thymus DNA through intercalation with an intrinsic binding constant K-b of 2.6 x 10(4) M-1, 5.7 x 10(4) M-1 and 4.5 x 10(4) M-1, respectively and they exhibited potent photo-damage abilities on pUC19 DNA, through singlet oxygen generation with quantum yields of 0.32, 0.27 and 0.30 respectively. The cytotoxic activity of the complexes resulted that they act as a potent photosensitizers for photochemical reactions. (C) 2012 Elsevier B.V. All rights reserved.

Metal based photosensitizers of tetradentate Schiff base: Promising role in anti-tumor activity through singlet oxygen generation mechanism

In the present investigation, a Schiff base N'(1),N'(3)-bis(Z)-(2-hydroxynapthyl)methylidene]benzene-1,3-dicarbod ihydrazide (L-1) and its Co(II), Ni(II) and Cu(II) complexes have been synthesized and characterized as novel photosensitizing agents for photodynamic therapy (PDT). The interaction of these complexes with calf thymus DNA (CT DNA) has been explored using absorption, thermal denaturation and viscometric studies. The experimental results revealed that Co(II) and Ni(II) complexes on binding to CT DNA imply a covalent mode, most possibly involving guanine N7 nitrogen of DNA, with an intrinsic binding constant K-b of 4.5 x 10(4) M-1 and 4.2 x 10(4) M-1, respectively. However, interestingly, the Cu(II) complex is involved in the surface binding to minor groove via phosphate backbone of DNA double helix with an intrinsic binding constant K-b of 5.7 x 10(4) M-1. The Co(II), Ni(II) and Cu(II) complexes are active in cleaving supercoiled (SC) pUC19 DNA on photoexposure to UV-visible light of 365 nm, through O-1(2) generation with quantum yields of 0.28, 0.25 and 0.30, respectively. Further, these complexes are cytotoxic in A549 lung cancer cells, showing an enhancement of cytotoxicity upon light irradiation. (C) 2013 Elsevier B.V. All rights reserved.

Anti-inflammatory activity of the ethanol extract of Dictamnus dasycarpus leaf in lipopolysaccharide-activated macrophages

Background: Dictamnus dasycarpus is widely used as a traditional remedy for the treatment of eczema, rheumatism, and other inflammatory diseases in Asia. The current study investigates the molecular mechanism of anti-inflammatory action of the ethanol extract of Dictamnus dasycarpus leaf (DE) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Methods: Nitric oxide (NO) production was assessed by Griess reaction and the mRNA and protein expressions of pro inflammatory cytokines, transcription factor, and enzymes were determined by real-time RT-PCR and immunoblotting analysis. Results: DE (0.5 and 1 mg/mL) suppressed the NO production by 10 and 33%, respectively, compared to the untreated group in LPS-stimulated RAW 264.7 cells. DE (0.5 and 1 mg/mL) reduced the mRNA expression of key transcription factor nuclear factor-kappa B by 7 and 24%, respectively compared to the untreated group in LPS activated macrophage. The pro inflammatory cytokines such as tumor necrosis factor a and interleukin 1 beta were also decreased by DE treatment. Moreover, the protein expression of pro inflammatory enzymes, inducible nitric oxide synthase and cyclooxygenase 2 were also dramatically attenuated by DE in a dose dependent manner. Conclusions: These results suggest that Dictamnus dasycarpus leaf has a potent anti-inflammatory activity and can be used for the development of new anti-inflammatory agents.

Phenyl carbohydrazone conjugated 2-oxoindoline as a new scaffold that augments the DNA and BSA binding affinity and anti-proliferative activity of a 1,10-phenanthroline based copper(II) complex

A new type of copper(II) complex, CuL(phen)(2)](NO3) (CuIP), where L ((E)-N'-(2-oxoindolin-3-ylidene) benzohydrazide) is a N donor ligand and phen is the N, N-donor heterocyclic 1,10-phenanthroline, has been synthesized. The phenyl carbohydrazone conjugated isatin-based ligand L and CuIP were characterized by elemental analysis, infrared, UV-Vis, H-1 and C-13 NMR and ESI-mass spectral data, as well as single-crystal X-ray diffraction. The interaction of calf thymus DNA (CT DNA) with L and CuIP has been investigated by absorption, fluorescence and viscosity titration methods. The complex CuIP displays better binding affinity than the ligand L. The observed DNA binding constant (K-b = 4.15(+/- 0.18) x 10(5) M-1) and binding site size (s = 0.19), viscosity data together with molecular docking studies of CuIP suggest groove binding and/or a partial intercalative mode of binding to CT DNA. In addition, CuIP shows good binding propensity to the bovine serum albumin (BSA) protein, giving a K-BSA value of 1.25(+/- 0.24) x 10(6) M-1. In addition, the docking studies on DNA and human serum albumin (HSA) CuIP interactions are consistent with the consequence of binding experiments. The in vitro anti-proliferative study establishes the anticancer potency of the CuIP against the human cervical (HeLa) and breast (MCF7) cancer cells; noncancer breast epithelial (MCF10a) cells have also been investigated. CuIP shows better cytotoxicity and sensitivity towards cancer cells over noncancer ones than L under identical conditions, with the appearance of apoptotic bodies. (C) 2014 Elsevier B.V. All rights reserved.