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Potent and specific inhibitors of hyaluronidases, a group of enzymes preferentially catalysing the hydrolysis of hyaluronic acid, are not known so far. Such compounds could be useful as pharmacological tools for studying the physiological and pathophysiological role of both hyaluronan and hyaluronidases. The effects of sulphated and non-sulphated structurally different oligosaccharides on bovine testicular hyaluronidase, hyaluronidase from bee venom and hyaluronate lyase from Streptococcus agalactiae (hylB (4755)) were studied with the Morgan-Elson reaction. Several active compounds were identified within a series of sulphated beta-(1,4)-galacto-oligosaccharides. The determined IC (50) values of these sulphated oligosaccharides ranged from 4 microM to 630 microM for all hyaluronan-degrading enzymes. Sulphated oligosaccharides like verbascose, planteose and neomycin showed comparable inhibition on all hyaluronidases, thereby possessing 100 - 500 times the activity of the widely accepted hyaluronidase inhibitor apigenin.

The ethanolic extract of Ilex aquifolium L. (Aquifoliaceae) concentration-dependently inhibited leukotriene B4 biosynthesis in isolated bovine PMNL with an IC50 value of about 60 micrograms/ml, whereas the effect on epidermal 12(S)-HETE biosynthesis was much less pronounced. The extract also inhibited the non-enzymatic, peroxyl radical-stimulated lipid peroxidation in model membranes and was further a scavenger of the iron-dependent generation of hydroxyl radicals from hydrogen peroxide as determined by protection against deoxyribose degradation. While inhibition of leukotriene biosynthesis was not mediated by its known phenolic constituents such as hyperoside, rutoside, and chlorogenic acid, these compounds were responsible for the inhibitory effects of I. aquifolium against non-enzymatic lipid peroxidation and deoxyribose degradation.

LAM S5 is a polysulphated derivative of the glucan laminarian that inhibits basic fibroblast growth factor (bFGF) binding and the bFGF-stimulated proliferation of fetal bovine heart endothelial (FBHE) cells. This report demonstrates that LAM S5 has anti-angiogenic activity, as shown by inhibition of tubule formation by endothelial cells cultured on Matrigel and inhibition of vascularisation of the chick chorioallantoic membrane. In addition, LAM S5 caused a tumour growth delay of the murine RIF-1 tumour of 2.6 days (P = 0.01). Images Figure 2

WOS: 000188262800014, PubMed ID: 14713159, Phlomis linearis Boiss. & Bal. of the Lamiaceae family growing in central, east and southeast Anatolia is an endemic species for Turkey. The essential oil obtained from the aerial parts by hydro distillation was subsequently analyzed by GC/MS. The main components of the oil were found as beta-caryophyllene (24.2%), germacrene D (22.3%) and caryophyllene oxide (9.2%), among 49 identified compounds, representing 94.5% of the total essential oil. The overall biological activity of the essential oil (100 mug/pellet) was tested on the chorioallantoic membrane (CAM) of the fertilized hen's egg in order to examine the anti-angiogenic and anti-inflammatory activity. None of the tests showed pronounced activity, toxicity or irritation at the tested concentration.

A new class of simple synthetic antimitotic compounds based on 2-aroylindoles was discovered. (5-Methoxy-1H-2-indolyl)-phenylmethanone (1) as well as analogous 3-fluorophenyl- (36) and 3-methoxyphenyl (3) derivatives displayed high cytotoxicity of IC(50) = 20 to 75 nM against the human HeLa/KB cervical, SK-OV-3 ovarian, and U373 astrocytoma carcinoma cell lines. The inhibition of proliferation correlated with the arrest in the G2/M phase of the cell cycle. In in vitro assays with tubulin isolated from bovine brain, in general antiproliferative activity correlated with inhibition of tubulin polymerization. Thus, the antimitotic activity of 2-aroylindoles is explained by interference with the mitotic spindle apparatus and destabilization of microtubules. In contrast to colchicine, vincristine, nocodazole, or taxol, 1 did not significantly affect the GTPase activity of beta-tubulin. Interestingly, selected compounds inhibited angiogenesis in the chorioallantoic membrane (CAM) assay. In xenograft experiments, 1 was highly active after oral administration at 200 mg/kg against the human amelanocytic melanoma MEXF 989 in athymic nude mice. We conclude, that 2-aroylindoles constitute an interesting new class of antitubulin agents with the potential to be clinically developed for cancer treatment.

Coupling anticancer drugs to synthetic polymers is a promising approach of enhancing the antitumor efficacy and reducing the side-effects of these agents. Doxorubicin maleimide derivatives containing an amide or acid-sensitive hydrazone linker were therefore coupled to alpha-methoxy-poly(ethylene glycol)-thiopropionic acid amide (MW 20000 Da), alpha,omega-bis-thiopropionic acid amide poly(ethylene glycol) (MW 20000 Da) or alpha-tert-butoxy-poly(ethylene glycol)-thiopropionic acid amide (MW 70000 Da) and the resulting polyethylene glycol (PEG) conjugates isolated through size-exclusion chromatography. The polymer drug derivatives were designed as to release doxorubicin inside the tumor cell by acid-cleavage of the hydrazone bond after uptake of the conjugate by endocytosis. The acid-sensitive PEG conjugates containing the carboxylic hydrazone bonds exhibited in vitro activity against human BXF T24 bladder carcinoma and LXFL 529L lung cancer cells with IC70 values in the range 0.02-1.5 microm (cell culture assay: propidium iodide fluorescence or colony forming assay). In contrast, PEG doxorubicin conjugates containing an amide bond between the drug and the polymer showed no in vitro activity. Fluorescence microscopy studies in LXFL 529 lung cancer cells revealed that free doxorubicin accumulates in the cell nucleus whereas doxorubicin of the acid-sensitive PEG doxorubicin conjugates is primarily localized in the cytoplasm. Nevertheless, the acid-sensitive PEG doxorubicin conjugates retain their ability to bind to calf thymus DNA as shown by fluorescence and visible spectroscopy studies. Results regarding the effect of an acid-sensitive PEG conjugate of molecular weight 20000 in the chorioallantoic membrane (CAM) assay indicate that this conjugate is significantly less embryotoxic than free doxorubicin although antiangiogenic effects were not observed.

We have evaluated a series of laminarin sulphates with different degrees of sulphation (0.3-2.3) as antagonists of basic fibroblast growth factor (bFGF) and as inhibitors of the bFGF-dependent endothelial cell line FBHE. Inhibition of binding of bFGF by the laminarin sulphates increased with increasing degree of sulphation. Binding of bFGF to low affinity sites on BHK cells was inhibited more strongly than binding to high affinity sites. IC50 values for inhibition of binding to low and high affinity sites by the most highly sulphated laminarin sulphate (LAM S5; degree of sulphation 2.31) were 12 +/- 8 micrograms/ml and 69 +/- 66 micrograms/ml, respectively. LAM S5 dissociated bFGF from low affinity sites on BHK cells but not from high affinity sites. LAM S5 increased the electrophoretic mobility of bFGF indicating that LAM S5 binds directly to bFGF. LAM S5 reduced uptake of bFGF by FBHE cells by 67%. Increasing the degree of sulphation of laminarin sulphates increased the inhibition of bFGF-stimulated DNA synthesis of the endothelial cell line FBHE (IC50 for LAM S5 approx. 1 microgram/ml). There was no inhibition of DNA synthesis of FBHE cells by LAM S5 in the presence of 1 microgram/ml bFGF indicating that bFGF antagonism is involved in the anti-proliferative activity of this compound. LAM S5 may be of value against diseases associated with bFGF-dependent cell proliferation.

International audience; Macrophages are key cells of innate immune response and serve as the first line of defense against bacteria. Transcription profiling of bacteria-infected macrophages could provide important insights on the pathogenicity and host defense mechanisms during infection. We have examined transcription profiles of bovine monocyte-derived macrophages (bMDMs) isolated from the blood of 12 animals and infected in vitro with two strains of Streptococcus agalactiae. Illumina sequencing of RNA from 36 bMDMs cultures exposed in vitro to either one of two sequence types of S. agalactiae (ST103 or ST12) for 6 h and unchallenged controls was performed. Analyses of over 1,656 million high-quality paired-end sequence reads revealed 5,936 and 6,443 differentially expressed genes (p < 0.05) in bMDMs infected with ST103 and ST12, respectively, versus unchallenged controls. Moreover, 588 genes differentially expressed between bMDMs infected with ST103 versus ST12 were identified. Ingenuity pathway analysis of the differentially up-regulated genes in the bMDMs infected with ST103 revealed significant enrichment for granulocyte adhesion and diapedesis, while significant enrichment for the phagosome formation pathway was found among down-regulated genes. Moreover, Ingenuity pathway analysis of the differentially up-regulated genes in the bMDMs infected with ST12 showed significant enrichment for type 1/type 2 T helper cell activation, while the complement activation pathway was overrepresented in the down-regulated genes. Our study identified pathogen-induced regulation of key genes and pathways involved in the immune response of macrophages against infection but also likely involved in bacterial evasion of the host immune system. These results may contribute to better understanding of the mechanisms underlying subclinical infection such as bovine streptococcal mastitis.

Kurtesh Sherifi and Rémi N. Charrel contributed equally to this article; International audience; Toscana and sandfly fever Sicilian viruses (TOSV and SFSV, respectively), both transmitted by sand flies, are prominent human pathogens in the Old World. Of 1,086 serum samples collected from cattle and sheep during 2013 in various regions of Kosovo (Balkan Peninsula), 4.7% and 53.4% had neutralizing antibodies against TOSV and SFSV, respectively.

Background Rift Valley fever (RVF) is a vector-borne disease affecting ruminants and humans. Madagascar was heavily affected by RVF in 2008–2009, with evidence of a large and heterogeneous spread of the disease. The identification of at-risk environments is essential to optimize the available resources by targeting RVF surveillance in Madagascar. Herein, the objectives of our study were: (i) to identify the environmental factors and areas favorable to RVF transmission to both cattle and human and (ii) to identify human behaviors favoring human infections in Malagasy contexts. Methodology/Principal Findings First, we characterized the environments of Malagasy communes using a Multiple Factor Analysis (MFA). Then, we analyzed cattle and human serological data collected at national level using Generalized Linear Mixed Models, with the individual serological status (cattle or human) as the response, and MFA factors, as well as other potential risk factors (cattle density, human behavior) as explanatory variables. Cattle and human seroprevalence rates were positively associated to humid environments (p, Author Summary Rift Valley fever virus (RVFV) is a pathogen that causes a vector-borne tropical disease. The disease affects ruminants and humans and severely impacts the health and economy of affected countries. Madagascar was heavily affected by Rift Valley fever (RVF) in 2008–2009, with evidence of a large and heterogeneous spread of the disease. Our study aims at identifying environmental and human-related risk factors for RVFV transmission. First, we characterized Malagasy environments according to their putative influence on RVFV mosquito density and population dynamics. Then we statistically analyzed cattle and human serological data collected at a national level with the individual serological status as response, and Malagasy environments previously characterized by climatic and landscape variables as well as other potential risk factors as explanatory variables. Our results identified humid environments of the western, north-western and eastern parts of the island as risky areas. The identification of at-risk environments is essential to focus veterinary surveillance and control of RVFV.