Antibacterial and cytotoxic activities of naphthoquinone pigments from Onosma visianii Clem

In this study, the antibacterial and cytotoxic activities of isolated compounds from the roots of Onosma visianii were investigated. By using different chromatographic techniques and appropriate spectroscopic methods, the seven naphthoquinones were described: deoxyshikonin (1), isobutyrylshikonin (2), α-methylbutyrylshikonin (3), acetylshikonin (4), ß-hydroxyisovalerylshikonin (5), 5,8-O-dimethyl isobutyrylshikonin (6) and 5,8-O-dimethyl deoxyshikonin (7). Among the tested compounds, 3 and 4 exhibited the highest antibacterial activities toward all tested bacterial species (MIC50 and MIC90 for gram positive bacteria: 6.40 µg/mL-12.79 µg/mL and 6.82 µg/mL-13.60 µg/mL, respectively; for gram negative bacteria: 4.27 µg/mL-8.53 µg/mL and 4.77 µg/mL-9.54 µg/mL, respectively). Also, naphthoquinones 3 and 4 exhibited strong cytotoxic activity against MDA-MB-231 cells (IC50 values 86.0 µg/mL and 80.2 µg/mL, respectively), while compounds 1, 3, 4 and 5 significantly decreased viability of HCT116 cells (IC50 values of 97.8 µg/mL, 15.2 µg/mL, 24.6 µg/mL and 30.9 µg/mL, respectively). Our results indicated that all tested naphthoquinone pigments are potential candidates for clinical uses as antibacterial and cytotoxic agents

Critical Role of Constitutive Type I Interferon Response in Bronchial Epithelial Cell to Influenza Infection

Innate antiviral responses in bronchial epithelial cells (BECs) provide the first line of defense against respiratory viral infection and the effectiveness of this response is critically dependent on the type I interferons (IFNs). However the importance of the antiviral responses in BECs during influenza infection is not well understood. We profiled the innate immune response to infection with H3N2 and H5N1 virus using Calu-3 cells and primary BECs to model proximal airway cells. The susceptibility of BECs to influenza infection was not solely dependent on the sialic acid-bearing glycoprotein, and antiviral responses that occurred after viral endocytosis was more important in limiting viral replication. The early antiviral response and apoptosis correlated with the ability to limit viral replication. Both viruses reduced RIG-I associated antiviral responses and subsequent induction of IFN-β. However it was found that there was constitutive release of IFN-β by BECs and this was critical in inducing late antiviral signaling via type I IFN receptors, and was crucial in limiting viral infection. This study characterizes anti-influenza virus responses in airway epithelial cells and shows that constitutive IFN-β release plays a more important role in initiating protective late IFN-stimulated responses during human influenza infection in bronchial epithelial cells

In vitro assay for the quantitative measurement of apoptotic lymphocytes phagocytosis by peripheral blood monocytes

Currently used assays for the quantification of apoptotic cells uptake by phagocytes have several methodological problems. Our assay overcomes some of these problems. As a source of apoptotic cells we used peripheral blood lymphocytes obtained from the patients with chronic lymphoblast leukaemia. Apoptosis was induced by incubating cells with cycloheximide for up to 24 h. The assay was performed in suspension of peripheral blood mononuclear cells. For the visualisation of the phagocytes and phagocyted cells and discrimination of phagocyted from bound apoptotic cells we used Acridine orange/Ethidium bromide double staining. Here we offer a simple test which enables reliable measurement and it can show the difference of phagocytic potential between different individual

Igm seroconversion to campylobacter jejuni in the first two years of life of children with Gastrointestinal Symptoms

Campylobacter is the most common bacteria isolated when sampling food and it is considered to be the most common cause of acute diarrhoea in people of all ages. In most countries, there are only data related to sporadic cases of Campylobacter infection, which is manifested by acute diarrhoea. The aim of this paper is to establish the existence of exposure to Campylobacter jejuni by serological analysis in healthy children under 2 years of age, who have previously had gastrointestinal symptoms. The examined group consisted of 77 healthy children under two years of age, who had had a history record of the existence of gastrointestinal symptoms prior to testing. Campylobacter concentration of IgM in serum was determined by ELISA method. Out of 77 children under the age of two, the existence of serum IgM antibodies to Campylobacter jejuni was confirmed in 32 children (42%), while the borderline result was found in 11 children (14%). Seroconversion occurs during the first year of life, and all children in the second year of life were IgM seropositive for Campylobacter jejuni. In the histories of seropositive children the most common symptoms had the form of heavy cramps in 48%. Considering the high incidence and variability of symptoms, the acquisition of Campylobacter jejuni is a major public health problem and there is a need to establish precise epidemiological data primarily in order to develop acquisition control of Campylobacter jejuni

Endoplasmic reticulum stress associated with caspases-4 and-2 mediates korbazol-induced B-chronic lymphocytic leukemia cell apoptosis

Purpose: B-cell chronic lymphocytic leukemia (B-CLL) is an incurable disease that rapidly develops drug resistance. Therefore there is a need for identifying new agents that will improve the therapeutic outcome. Korbazol is a natural product known to exert cytotoxic effect on the in vitro survival of leukemic cells. The aim of this study was to investigate the mechanism of korbazol-induced apoptosis in B-CLL leukemic cells. Methods: Peripheral blood mononuclear cells from 10 B-CLL patients were used for assessing the effect of caspase inhibitors and chelator of intracellular Ca2+ Results: Cell death rate induced by the tested compound was decreased with the caspase-3 inhibitor Ac-DEVD-CHO, and the inhibitors of caspase-2 (Z-VDVAD-FMK) and -4 (ZYVAD-FMK), but not with the caspase-9 inhibitor z-LEHD-FMK and caspase-8 inhibitor z-IETD-FMK No significant release of cytochrome C (cyt C) from mitochondria to the cytosol of B-CLL cells treated with korbazol was observed. Moreover, chelating of intracellular Ca2+ with BAPTA-AM almost completely abolished the cytotoxic effect of korbazol. Conclusion: Engagement of caspases-2 and -4 and mobilization of intracellular Ca2+ indicate involvement of endoplasmic reticulum (ER) stress in apoptosis induced by korbazol

Structural, biological and computational study of oxamide derivative|СТРУКТУРНА, БИОЛОШКА И РАЧУНСКА ИПИТИВАЊА ДЕРИВАТА ОКСАМИДА

A dicarboxylato-diamide-type compound 2,2'-[(1,2-dioxoethane-1,2--diyl)diimino]dibenzoicacid (H(4)obbz) (1) was synthesized and characterized. The crystal structure of K(2)H(2)obbz center dot 2H(2)O (2) was determined by X-ray diffract-tion analysis. The cytotoxic activities of the compounds were tested against four different cancer cell lines MCF-7, A549, HT-29, HeLa and a human nor-mal cell line MRC-5. The results indicate reasonable dose-dependent cytotox-icity of the ligands that show selectivity against the tested carcinoma and healthy cell lines. Flow cytometric analysis and fluorescence microscopy showed that the most active compound, H(4)obbz, induced apoptosis and G0/G1 cell cycle arrest, indicating blockage of DNA synthesis as a possible mechanism that trig-gers apoptosis. Docking and molecular dynamics simulations gave similar res-ponses regarding interactions (binding) between their ligands and chaperon Grp78. The MMGBSA determined Delta G binding energies were in the range from -104 to -140 kJ mol(-1)

New dinuclear palladium(II) complexes: Studies of the nucleophilic substitution reactions, DNA/BSA interactions and cytotoxic activity

Six new dinuclear Pd(II) complexes, [{Pd(2,2-bipy)Cl}(2)(mu-pz)](ClO4)2 (Pd1), [{Pd(dach)Cl}(2)(mu-pz)](ClO4)(2) (Pd2), [{Pd(en)Cl}(2)(mu-pz)] (ClO4)(2) (Pd3), [{Pd(2,2-bipy)Cl}(2)(mu-4,4-bipy)](ClO4)(2) (Pd4), [{Pd(dach)Cl}(2)(mu-4,4-bipy)] (ClO4)(2) (Pd5) and [{Pd(en)Cl-2(mu-4,4-bipy)](ClO4)(2) (Pd6) (where 2,2-bipy = 2,2-bipyridyl, pz = pyrazine, dach = trans-(+/-)-1,2-diaminocyclohexane, en = ethylenediamine, 4,4-bipy = 4,4-bipyridyl) have been synthesized and characterized by elemental microanalysis, IR, H-1 NMR and MALDI-TOF mass spectrometry. The pK(a) values of corresponding diaqua complexes were determined by spectrophotometric pH titration. Substitution reactions with thiourea (Tu), L-methionine (L-Met), L-cysteine (L-Cys), L-histidine (L-His) and guanosine-5-monophosphate (5-GMP) were studied under the pseudo-first order conditions at pH 7.2. Reactions of Pdl with Tu, L-Met and L-Cys were followed by decomposition of complexes, while structures of dinuclear complexes were preserved during the substitution with nitrogen donors. Interactions with calf-thymus DNA (CT DNA) were followed by absorption spectroscopy and fluorescence quenching measurements. All complexes can bind to CT-DNA exhibiting high intrinsic binding constants (K-b = 10(4)-10(5) M-1). Competitive studies with ethidium bromide (EB) have shown that complexes can displace DNA-bound EB. High values of binding constants towards bovine serum albumin protein (BSA) indicate good binding affinity. Finally, all complexes showed moderate to high cytotoxic activity against HeLa (human cervical epithelial carcinoma cell lines) and MDA-MB-231 (human breast epithelial carcinoma cell lines) tumor cell lines inducing apoptotic type cell death, whereas normal fibroblasts were significantly less sensitive. The impact on cell cycle of these cells was distinctive, where Pd4, Pd5 and Pd6 showed the most prominent effect arresting MDA-MB-231 (human lung fibroblast cell lines) cell in G1/S phase of cell cycle