Search results for "rites"
showing 10 items of 427 documents
Potential biological role of laccase from the sponge Suberites domuncula as an antibacterial defense component
2014
Abstract Background Laccases are copper-containing enzymes that catalyze the oxidation of a wide variety of phenolic substrates. Methods We describe the first poriferan laccase from the marine demosponge Suberites domuncula. Results This enzyme comprises three characteristic multicopper oxidase homologous domains. Immunohistological studies revealed that the highest expression of the laccase is in the surface zone of the animals. The expression level of the laccase gene is strongly upregulated after exposure of the animals to the bacterial endotoxin lipopolysaccharide. To allow the binding of the recombinant enzyme to ferromagnetic nanoparticles, a recombinant laccase was prepared which con…
Interaction of dicaffeoylquinic derivatives with peroxynitrite and other reactive nitrogen species.
2008
Plant phenolic antioxidants, among them catechins and hydroxycinnamoyl conjugates, constitute a well defined class of inhibitors of reactive nitrogen species (RNS). To gain deeper insight in this field, we examined the effects of 3,5-di-O-caffeoylquinic acid (DCA), its methyl ester (DCE) and epigallocatechin gallate (EGCG) in nitrative and oxidative processes. These compounds were found to be strong inhibitors of the nitration of tyrosine residues induced by ONOO- in bovine seroalbumin, with their IC50 values (10-40 microM) notably decreasing in the presence of bicarbonate. When studied on the intracellular protein tyrosine nitration induced by ONOO- in cultured murine fibroblasts as well a…
Histocompatibility reaction in tissue and cells of the marine sponge Suberites domuncula in vitro and in vivo: central role of the allograft inflamma…
2001
Sponges (Porifera) are the phylogenetically oldest still extant metazoan phylum. Recently elements of their immune system have been cloned and analyzed, primarily from the demosponges Suberites domuncula and Geodia cydonium. By differential display, two genes were identified in S. domuncula, whose translation products are involved in graft rejection/fusion: the allograft inflammatory factor (AIF-1) and the Tcf-like transcription factor (TCF). Since the AIF-1 and TCF genes are upregulated in vivo after tissue transplantation, especially in allografts, we investigated whether this reaction can be monitored in vitro. Therefore, the autogeneic and the allogeneic mixed sponge cell reaction (MSCR…
Transmembrane form agrin-induced process formation requires lipid rafts and the activation of Fyn and MAPK.
2009
Overexpression or clustering of the transmembrane form of the extracellular matrix heparan sulfate proteoglycan agrin (TM-agrin) induces the formation of highly dynamic filopodia-like processes on axons and dendrites from central and peripheral nervous system-derived neurons. Here we show that the formation of these processes is paralleled by a partitioning of TM-agrin into lipid rafts, that lipid rafts and transmembrane-agrin colocalize on the processes, that extraction of lipid rafts with methyl-β-cyclodextrin leads to a dose-dependent reduction of process formation, that inhibition of lipid raft synthesis prevents process formation, and that the continuous presence of lipid rafts is requ…
Midostaurin upregulates eNOS gene expression and preserves eNOS function in the microcirculation of the mouse
2005
Nitric oxide (NO) derived from endothelial NO synthase (eNOS) is a powerful vasodilator and possesses vasoprotective effects. Therefore, augmentation of eNOS expression and -activity by pharmacological means could provide protection against cardiovascular disease. However, this concept has been questioned recently, because in several disease models, eNOS upregulation was associated with a dysfunctional enzyme (referred to as eNOS uncoupling). In contrast, the present study demonstrates that an eNOS gene expression-enhancing compound with additional protein kinase C (PKC) inhibitory properties can upregulate eNOS while preserving its enzymatic function. Apolipoprotein E-knockout mice were tr…
Functional Inactivation of the Genome-Wide Association Study Obesity Gene Neuronal Growth Regulator 1 in Mice Causes a Body Mass Phenotype
2012
To date, genome-wide association studies (GWAS) have identified at least 32 novel loci for obesity and body mass-related traits. However, the causal genetic variant and molecular mechanisms of specific susceptibility genes in relation to obesity are yet to be fully confirmed and characterised. Here, we examined whether the candidate gene NEGR1 encoding the neuronal growth regulator 1, also termed neurotractin or Kilon, accounts for the obesity association. To characterise the function of NEGR1 for body weight control in vivo, we generated two novel mutant mouse lines, including a constitutive NEGR1-deficient mouse line as well as an ENU-mutagenised line carrying a loss-of-function mutation …
Effect of nitrite on microsomal cytochrome P-450.
1978
1. Addition of nitrite to anaerobic rat liver microsomes leads to the appearance of a difference spectrum similar to the spectrum of the ferrous cytochrome P-450-NO complex. A Soret band is found at 444 nm in phenobarbital-stimulated microsomes but at 442 nm in 3-methylcholanthrene-stimulated microsomes. An alpha-band is located at 583 nm in both types of microsome. 2. The initial nitrite-induced difference spectrum is converted into a spectrum lacking a Soret band but with a prominent absorbance minimum at 417 nm. This is more rapid in microsomes from phenobarbital-treated animals where it is completed in 8 min than in microsomes from 3-methylcholanthrene-treated animals. A similar spectru…
Chronic stress induces changes in the structure of interneurons and in the expression of molecules related to neuronal structural plasticity and inhi…
2011
Chronic stress in experimental animals, one of the most accepted models of chronic anxiety and depression, induces structural remodeling of principal neurons in the amygdala and increases its excitation by reducing inhibitory tone. These changes may be mediated by the polysialylated form of the neural cell adhesion molecule (PSA-NCAM), a molecule related to neuronal structural plasticity and expressed by interneurons in the adult CNS, which is downregulated in the amygdala after chronic stress. We have analyzed the amygdala of adult mice after 21 days of restraint stress, studying with qRT-PCR the expression of genes related to general and inhibitory neurotransmission, and of PSA synthesizi…
Molecular markers for germ cell differentiation in the demosponge Suberites domuncula
2004
Sponges (phylum Porifera) are simple metazoans for which no molecular information on gametogenesis and larval development is available. To support the current study, it was confirmed by histology that oocytes and larvae were produced by the demosponge Suberites domuncula. Three genes/expressed products from S. domuncula whose expression correlated with sexual reproduction were identified and characterized (they are used here as marker genes): i) a receptor tyrosine kinase (RTK) with sequence similarity in the tyrosine kinase domain to fibroblast growth factor receptors; ii) the sex-determining protein FEM1 and iii) the sperm associated antigen (SAA) of triploblasts. Antibodies against the e…
Silibinin improves hepatic and myocardial injury in mice with nonalcoholic steatohepatitis
2012
Abstract Background Nonalcoholic fatty liver disease is a chronic metabolic disorder with significant impact on cardiovascular and liver mortality. Aims In this study, we examined the effects of silibinin on liver and myocardium injury in an experimental model of nonalcoholic fatty liver disease. Methods A four-week daily dose of silibinin (20 mg/kg i.p.) was administrated to db/db mice fed a methionine–choline deficient diet. Hepatic and myocardial histology, oxidative stress and inflammatory cytokines were evaluated. Results Silibinin administration decreased HOMA-IR, serum ALT and markedly improved hepatic and myocardial damage. Silibinin reduced isoprostanes, 8-deoxyguanosine and nitrit…