Trimethylbenzenes (Interagency Science Discussion Draft)

Project ID

2375

Category

IRIS

Added on

June 29, 2015, 10:57 a.m.

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Journal Article

Abstract  Antibody display methods are increasingly being used to produce human monoclonal antibodies for disease therapy. Rapid screening and isolation of specific human antibody genes are valuable for producing human monoclonal antibodies showing high specificity and affinity. In this report, we describe a novel mammalian cell display method in which whole human IgG is displayed on the cell surface of CHO cells. Cells expressing antigen-specific human monoclonal IgGs with high affinity on the cell surface after normal folding and posttranscriptional modification were screened using a cell sorter. The membrane-type IgG-expressing CHO cells were then converted to IgG-secreting cells by transfection with a plasmid coding Cre recombinase. This mammalian cell display method was applied to in vitro affinity maturation of monoclonal C9 IgG specific to the human high-affinity IgE receptor (FcεRIα). The CDR3 of the C9 heavy chain variable region gene was randomly mutated and inserted into pcDNA5FRT/IgG. A C9 IgG (CDRH3r)-expressing CHO cell display library consisting of 1.1×10(6) independent clones was constructed. IgG-displaying cells showing high reactivity to FcεRIα antigen were screened by the cell sorter, resulting in the establishment of a CHO cell line producing with higher reactivity than the parent C9 IgG.

Journal Article

Abstract  Recombination is a major mechanism generating genetic diversity, but the control of the crossover rate remains a key question. In Brassica napus (AACC, 2n = 38), we can increase the homologous recombination between A genomes in AAC hybrids. Hypotheses for this effect include the number of C univalent chromosomes, the ratio between univalents and bivalents and, finally, which of the chromosomes are univalents. To test these hypotheses, we produced AA hybrids with zero, one, three, six or nine additional C chromosomes and four different hybrids carrying 2n = 32 and 2n = 35 chromosomes. The genetic map lengths for each hybrid were established to compare their recombination rates. The rates were 1.4 and 2.7 times higher in the hybrids having C6 or C9 alone than in the control (0C). This enhancement reached 3.1 and 4.1 times in hybrids carrying six and nine C chromosomes, and it was also higher for each pair of hybrids carrying 2n = 32 or 2n = 35 chromosomes, with a dependence on which chromosomes remained as univalents. We have shown, for the first time, that the presence of one chromosome, C9 , affects significantly the recombination rate and reduces crossover interference. This result will have fundamental implications on the regulation of crossover frequency.

Journal Article

Abstract  AIMS: Oxylipins are regarded as unsaturated fatty acids (UFAs) oxidation products, whose accumulation in plants and fungi is associated with stress. The aim of this study was to investigate if a metabolic pathway from UFAs to oxylipins was present also in lactic acid bacteria (LAB).

METHODS AND RESULTS: A strain of Lactobacillus helveticus, incubated in the presence of oleic, linoleic and linolenic acids released, after 2 h, fatty acid oxidation products, mainly C6 , C8 , C9 aldehydes and alcohols. An experiment with total carbon labelled linoleic acid, in the presence or not of an oxidative stress, demonstrated that oxylipins, such as hexanal, octanal, nonanal, 2-octenal, 2-octanal, originated mainly from the oxidation of this fatty acid.

CONCLUSIONS: Since lipoxygenase, dioxygenase and cytochrome P450 genes have never been found in L. helveticus, a possible pathway for linoleic conversion and oxylipins formation could include, as a first step, the transient formation of hydroxylated linoleic acids by fatty acids hydratases. However, the sequence of steps from the linoleic acid to the C6 and C8 aldehydes needs to be more deeply investigated.

SIGNIFICANCE AND IMPACT OF THE STUDY: Due to the multiple role of oxylipins which are flavouring agents, antimicrobial compounds and interspecific signalling molecules, the knowledge of the mechanisms involved in their biosynthesis in food related bacteria could have an important biotechnological impact, also allowing the overproduction of selected bioactive molecules.

Journal Article

Abstract  Results from a 13-week inhalation study in rats on a C10-C12 isoparaffinic solvent are compared to the results of repeated inhalation and oral toxicity studies of four other isoparaffinic hydrocarbon solvents. Statistically significant findings which were consistent across all studies included: nephropathy and small but significant changes in hematological parameters in male rats and liver enlargement in both male and female rats. The male rat kidney changes were due to an alpha 2u globulin process and not relevant for human health or risk assessment. The liver enlargement without pathologic changes or elevations in liver enzyme markers was considered to be an adaptive response. The reason for the reductions in hematological parameters that were observed in males only is not clear, but it is suggested that these were either due to normal variation or a secondary consequence of the nephropathy. The overall No Observed Adverse Effect Concentration (NOAEC) was the highest concentration tested in the study, >10,000 mg/m(3). Because of the overall pattern of response, this solvent is considered to be representative of low aromatic C9-C14 aliphatic solvents in general. The data are useful for risk assessment and other purposes including the development of occupational exposure recommendations.

Journal Article

Abstract  Many species belonging to the order Lepidoptera are major pests in agriculture and arboriculture. The sterile insect technique (SIT) is an eco-friendly and highly efficient genetically targeted pest management approach. In many cases, it is preferable to release only sterile males in an SIT program, and efficient sexing strategies are crucial to the successful large-scale implementation of SIT. In the present study, we established 160 transgenic silkworm (Bombyx mori) lines to test the possibility of genetic sexing using a W chromosome-linked transgene, which is thought to be the best sexing strategy for lepidopteran species. One transgenic line with a female-specific expression pattern of reporter gene was obtained. The expression level of the W-linked transgene was comparable with autosomal insertions and was stable for 17 continuous generations. Molecular characterization showed this line contained a single copy of the reporter gene on the W chromosome, and the integration site was TTAG in contig W-BAC-522N19-C9. The feasibility of using a W chromosome-linked transgene demonstrated here and the possible improvements discussed will provide valuable information for other lepidopteran pests. The novel W chromosome-linked transgenic line established in this study will serve as an important resource for fundamental research with the silkworm B. mori.

Journal Article

Abstract  Ghrelin is a peptide hormone that is acylated with a fatty acid, usually n-octanoic acid, at the third amino acid (aa) residue (usually a serine or threonine), and this acylation is known to be essential for ghrelin activity not only in mammals but also in non-mammals, such as fish. However, the modification mechanisms of ghrelin modification in fish are not known. In this study, we elucidated the structure of ghrelin in a teleost, the barfin flounder (Verasper moseri), and determined whether ingested free fatty acids of various chain lengths participated in ghrelin acylation. Complementary DNA cloning revealed the barfin flounder prepro-ghrelin to be a 106-aa peptide and the mature ghrelin to be a 20-aa peptide (GSSFLSPSHKPPNKGKPPRA). However, purification of ghrelin peptides from stomach extracts demonstrated that the major form of the hormone was a 19-aa decanoylated peptide [GSS(C10:0)FLSPSHKPPNKGKPPR] missing the last alanine of the 20-aa peptide. Ingestion of feed enriched with n-heptanoic acid (C7), n-octanoic acid (C8), or n-non-anoic acid (C9) changed the modification status of the peptide: ingestion of C8 or C9 increased the amount of C8:0 or C9:0 19-aa ghrelin, respectively, but no C7:0 ghrelin was isolated after ingestion of C7. These results indicate that ingested free fatty acids are substrates for ghrelin acylation in the barfin flounder, but the types of free fatty acids utilized as substrates may be limited.

Journal Article

Abstract  Numerous studies have shown that conjugated linoleic acid (CLA) can inhibit cancer cells growth and induce apoptosis in vitro and in vivo. The aim of the present study was to investigate the effects of CLA, including cis9, trans11-conjugated linoleic acid (c9, t11-CLA) and trans10, cis12-conjugated linoleic acid (t10, c12-CLA), on apoptosis of human endometrial cancer RL 95-2 cells and its related mechanisms. The MTT analysis was used to evaluate the effect of CLA isomers on the viability of endometrial cancer RL 95-2 cells. We then estimated the apoptosis by Morphological observation and Annexin V-FITC/PI staining and flow cytometry. We also used Western blot analysis to assess the expression of caspase-3, Bax, Bcl-2 proteins and the activation of Akt/p-Akt and ERα/p-ERα. Propylpyrazole-triol (PPT), a selective ERα agonist was used to confirm the induction of apoptosis by c9, t11 CLA may relate to ERα-mediated pathway. In CLA-treated RL 95-2 cells, we found that c9, t11-CLA inhibited viability and trigged apoptosis, as judged from nuclear morphology and flow cytometric analysis. The expression of caspase-3 and the ratio of Bax/Bcl-2 were significant increased, but no obvious change was observed about Akt and p-Akt in c9, t11-CLA-treated cells. However, the expression of total ERα level in RL 95-2 cells-treated with c9, t11-CLA was unchanged, while in the concentration of 80 mM, c9, t11-CLA down-regulated the protein expression level of p-ERα. Then PPT has the antagonistic action on growth inhibitory effect in RL 95-2 cells incubated with c9, t11-CLA. This study demonstrated that c9, t11- CLA could induce apoptosis in RL 95-2 cells, and may involve in ERα-mediated pathway. These results indicated that c9, t11- CLA could induce apoptosis of endometrial cancer cells and may be potential agents for the treatment of endometrial cancer.

Journal Article

Abstract  OBJECTIVES: The complement system is involved in many immune complex-mediated kidney diseases, yet its role in the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD) has not been examined in detail.

METHODS AND RESULTS: Screening of the glycoproteome of urine samples from ADPKD patients revealed that levels of complement factor B (CFB), serpin peptidase inhibitor, complement component 1 inhibitor (SERPING1) and complement component 9 (C9) increased, whereas complement component 1, r subcomponent-like (C1RL), CD55 and CD59 levels decreased with disease progression. Immunostaining and Western blot analysis confirmed the enhanced expression of CFB and C9 in cystic kidneys from ADPKD patients. Immunostaining also showed that the expressions of CFB and C9 in renal biopsy tissues from patients with other types of chronic kidney disease were lower than in tissues from ADPKD patients. The effect of the complement inhibitor rosmarinic acid (RMA) was evaluated in Pkd1(-/-) mice and Han:SPRD Cy/+ rats. Compared with vehicle-treated Pkd1(-/-) animals, RMA-treated mice had significantly lower serum creatinine (-50%) and blood urea nitrogen (-78%) levels, two kidneys/body weight ratio (-60%) and renal cystic index (-60%). Similar results were found in Cy/+ rats. Lower numbers of Ki67-positive nuclei and inflammatory cells and reduced fibrosis were observed in both animal models upon treatment with RMA.

CONCLUSIONS: These results suggest that excessive activation of the alternative complement pathway is associated with ADPKD progression, probably mediated by cyst-lining epithelial cell proliferation, tubulointerstitial inflammatory cell infiltration and fibrosis. Targeting the complement system might represent a new therapeutic strategy for ADPKD.

Journal Article

Abstract  This report describes the synthesis and in vitro anti-malarial evaluations of certain C2 or C8 and C11-disubstituted 6-methyl-5H-indolo[2,3-b]quinoline (neocryptolepine congener) derivatives. To attain higher activities, the structure–activity relationship (SAR) studies were conducted by varying the kind of alkylamino or ω-aminoalkylamino stubstituents at C11 and with Cl at the C2 position, or CO2Me at the C9 position. The anti-malarial activities of the tested compounds were significantly increased compared to the 11-non(alkylamino) derivatives. The 3-aminopropylamino group at C11 was further modified to urea and thiourea, which improved the cytotoxicity against normal cells. The best results were achieved with compounds 8 and 9d against the NF54 strain with the IC(50)/SI values as of 86 nM/20 and 317 nM/370, respectively. Furthermore, the compounds were tested for β-haematin inhibition. Twelve were found to have IC(50) values below 100 µM and a linear correlation between the β-haematin inhibition and cell growth inhibition in the NF54 strain was found for those derivatives with basic amino side chains. A second correlation was identified between the NF54 activity and physico-chemical factors related to solvation and polarity.

Journal Article

Abstract  The major conjugated linoleic acid (CLA) isomers, c9,t11-CLA and t10,c12-CLA, have anticancer effects; however, the exact mechanisms underlying these effects are unknown. Evidence suggests that reversal of reduced gap junctional intercellular communication (GJIC) in cancer cells inhibits cell growth and induces cell death. Hence, we determined that CLA isomers enhance GJIC in human MCF-7 breast cancer cells and investigated the underlying molecular mechanisms. The CLA isomers significantly enhanced GJIC of MCF-7 cells at 40  μ M concentration, whereas CLA inhibited cell growth and induced caspase-dependent apoptosis. CLA increased connexin43 (Cx43) expression both at the transcriptional and translational levels. CLA inhibited nuclear factor- κ B (NF- κ B) activity and enhanced reactive oxygen species (ROS) generation. No significant difference was observed in the efficacy of c9,t11-CLA and t10,c12-CLA. These results suggest that the anticancer effect of CLA is associated with upregulation of GJIC mediated by enhanced Cx43 expression through inactivation of NF- κ B and generation of ROS in MCF-7 cells.

Journal Article

Abstract  The complement system is activated in a wide spectrum of CNS diseases and is suggested to play a role in degenerative phenomena such as elimination of synaptic terminals. Still, little is known of mechanisms regulating complement activation in the CNS. Loss of synaptic terminals in the spinal cord after an experimental nerve injury is increased in the inbred DA strain compared with the PVG strain and is associated with expression of the upstream complement components C1q and C3, in the absence of membrane attack complex activation and neutrophil infiltration. To further dissect pathways regulating complement expression, we performed genome-wide expression profiling and linkage analysis in a large F2(DA × PVG) intercross, which identified quantitative trait loci regulating expression of C1qa, C1qb, C3, and C9. Unlike C1qa, C1qb, and C9, which all displayed distinct coregulation with different cis-regulated C-type lectins, C3 was regulated in a coexpression network immediately downstream of butyrylcholinesterase. Butyrylcholinesterase hydrolyses acetylcholine, which exerts immunoregulatory effects partly through TNF-α pathways. Accordingly, increased C3, but not C1q, expression was demonstrated in rat and mouse glia following TNF-α stimulation, which was abrogated in a dose-dependent manner by acetylcholine. These findings demonstrate new pathways regulating CNS complement expression using unbiased mapping in an experimental in vivo system. A direct link between cholinergic activity and complement activation is supported by in vitro experiments. The identification of distinct pathways subjected to regulation by naturally occurring genetic variability is of relevance for the understanding of disease mechanisms in neurologic conditions characterized by neuronal injury and complement activation.

Journal Article

Abstract  Pyrrolizidine alkaloid-containing plants are probably the most common poisonous plants affecting livestock, wildlife, and humans. Pyrrolizidine alkaloids exert toxicity through metabolism to dehydropyrrolizidine alkaloids that bind to cellular protein and DNA, leading to hepatotoxicity, genotoxicity, and tumorigenicity. To date, it is not clear how dehydropyrrolizidine alkaloids bind to cellular constituents, including amino acids and proteins, resulting in toxicity. Metabolism of carcinogenic monocrotaline, riddelliine, and heliotrine produces dehydromonocrotaline, dehyroriddelliine, and dehydroheliotrine, respectively, as primary reactive metabolites. In this study, we report that reaction of dehydromonocrotaline with valine generated four highly unstable 6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP)-derived valine (DHP-valine) adducts. For structural elucidation, DHP-valine adducts were derivatized with phenyl isothiocyanate (PITC) to DHP-valine-PITC products. After HPLC separation, their structures were characterized by mass spectrometry, UV-visible spectrophotometry, (1)H NMR, and (1)H-(1)H COSY NMR spectral analysis. Two DHP-valine-PITC adducts, designated as DHP-valine-PITC-1 and DHP-valine-PITC-3, had the amino group of valine linked to the C7 position of the necine base, and the other two DHP-valine-PITC products, DHP-valine-PITC-2 and DHP-valine-PITC-4, linked to the C9 position of the necine base. DHP-valine-PITC-1 was interconvertible with DHP-valine-PITC-3, and DHP-valine-PITC-2 was interconvertible with DHP-valine-PITC-4. Reaction of dehydroriddelliine and dehydroheliotrine with valine provided similar results. However, reaction of valine and dehydroretronecine (DHR) under similar experimental conditions did not produce DHP-valine adducts. Reaction of dehydromonocrotaline with rat hemoglobin followed by derivatization with PITC also generated the same four DHP-valine-PITC adducts. This represents the first full structural elucidation of protein conjugated pyrrolic adducts formed from reaction of dehydropyrrolizidine alkaloids with an amino acid (valine). In addition, it was found that DHP-valine-2 and DHP-valine-4, with the valine amino group linked at the C7 position of the necine base, can lose the valine moiety to form DHP.

Journal Article

Abstract  Contact dermatitis is the second most reported occupational injury associated with workers compensation. Inflammatory cytokines are closely involved with the development of dermatitis, and their modulation could exacerbate skin damage, thus contributing to increased irritancy. IL-6 is a pro-inflammatory cytokine paradoxically associated with both skin healing and inflammation. To determine what role this pleiotropic cytokine plays in chemically-induced irritant dermatitis, IL-6 deficient (KO), IL-6 over-expressing transgenic (TgIL6), and corresponding wild-type (WT) mice were exposed to acetone or the irritants JP-8 jet fuel or benzalkonium chloride (BKC) daily for 7 days. Histological analysis of exposed skin was performed, as was tissue mRNA and protein expression patterns of inflammatory cytokines via QPCR and multiplex ELISA. The results indicated that, following JP-8 exposure, IL-6KO mice had greatly increased skin IL-1β, TNFα, CCL2, CCL3, and CXCL1 mRNA and corresponding product protein expression when compared to that of samples from WT counterparts and acetone-exposed control mice. BKC treatment induced the expression of all cytokines examined as compared to acetone, with CCL2 significantly higher in skin from IL-6KO mice. Histological analysis showed that IL-6KO mice displayed significantly more inflammatory cell infiltration as compared to WT and TgIL6 mice in response to jet fuel. Analysis of mRNA for the M2 macrophage marker CD206 indicated a 4-fold decrease in skin of IL-6KO mice treated with either irritant as compared to WT. Taken together, these observations suggest that IL-6 acts in an anti-inflammatory manner during irritant dermatitis, and these effects are dependent on the chemical nature of the irritant.

Technical Report
Journal Article

Abstract  Two homogeneous water-soluble polysaccharides (TPSR4-2B and TPSR4-2C) were obtained from preinfused green tea. Their average molecular weights were estimated to be 41 kDa and 28 kDa, respectively. A combination of composition, methylation, and configuration analysis, as well as NMR spectroscopy, indicated that both TPSR4-2B and TPSR4-2C were poly-(1-4)-α-d-galactopyranosyluronic acid in which 30.5 ± 0.3% and 28.3 ± 0.5%, respectively, of uronic acid existed as methyl ester. Two sulfated derivatives (Sul-R4-2B and Sul-R4-2C) from TPSR4-2B and TPSR4-2C were prepared after sulfation with a 2:1 chlorosulfonic acid-pyridine ratio. The anticomplementary assay showed that Sul-R4-2B and Sul-R4-2C demonstrated a stronger inhibitory effect on the complement activation through the classic pathway, compared to that of heparin. Preliminary mechanism studies by using complement component depleted-sera indicated that both Sul-R4-2B and Sul-R4-2C selectively interact with C1q, C1r, C1s, C2, C5, and C9 but not with C3 and C4. The relationship between DS and the anticomplementary activity of sulfated derivatives of homogalacturonans showed that low sulfated derivatives of homogalacturonans also exhibited potent anticomplementary effect, which might greatly reduce the side effects related to heparin and oversulfated chondroitin sulfate, such as anticoagulant activity and allergic-type reaction. These results suggested that sulfated derivatives of homogalacturonans might be promising drug candidates for therapeutic complement inhibition.

Journal Article

Abstract  Sheep milk is rich in CLA isomers which are biologically active components influencing human health. There are four geometric CLA isomer pairs: cis, trans; trans, cis; trans, trans and cis, cis. The aim of the present study was the analysis of CLA isomer groups content by Ag+-HPLC in milk fat of Zelazneńska (ZS) and Wrzosówka (WS) sheep breeds. The ewes of both breeds were kept under the same environmental and nutritional conditions. Milk samples were collected from 60 suckling ewes (30 from each breed), at the age of 3-4 years and in their 4th week of lactation. A higher total amount of all CLA isomer groups was obtained in milk of ZS ewes, however, this result was statistically insignificant. The percentage of the main c9, t11 isomer in total CLA was higher in Wrzosówka milk (68% vs. 74%). The content of the trans, trans isomer group in milk fat of the studied breeds was similar. The percentage of this group in total CLA in milk of WS and ZS constitutes 7.2% and 7.7%, respectively. The amount of cis,cis isomers in milk fat of ZS was higher thanWS (P < or = 0.01).

Journal Article

Abstract  INTRODUCTION: Pulmonary embolism (PE) is a disease with a high mortality and morbidity rate, and the pathogenesis of PE remains still unclear. We aimed to investigate the gene expression differences of the complement system in peripheral blood mononuclear cells (PBMCs) from patients with symptomatic PE and controls.

METHODS: Twenty cases of PE patients and twenty sex and age matched controls were recruited into the study. Human cDNA microarray analysis was used to detect the gene expression difference of the complement system between the two groups.

RESULTS: 1). Expression of twenty-one genes encoding complement components was detected. In PE patients, expression of the genes encoding C1qα, C1qβ, C4b, C5 and Factor P was significantly greater (P<0.05) than controls, while C6, C7, C9, mannose-binding lectin (MBL) and mannan-binding lectin serine peptidase 1 (MASP1) mRNAs were lower (P<0.05) than controls. 2). Expression of seven genes encoding complement receptors was examined. In PE patients, CR1, integrin αM, integrin αX and C5aR mRNAs were significantly up-regulated (P<0.01) compared with controls. 3). Seven genes encoding complement regulators were examined. The mRNA expression of CD59 and CD55 was significantly up-regulated (P<0.05), whereas Factor I mRNA was significantly down-regulated (P<0.05) in PE patients than controls.

CONCLUSIONS: In PE patients, the mRNA expressions of complement components, receptors and regulators were unbalanced, suggesting dysfunction and/or deficiency of the complement system, which leads to decreased function of MAC-induced cell lysis in PE patients finally.

Journal Article

Abstract  Complement system is known as highly sophisticated immune defense mechanism for antigen recognition as well as effector functions. Activation of the terminal pathway of the complement system leads to the assembly of terminal complement complexes (C5b-9), which induces the characteristic complement-mediated cytolysis. The lytic activity of shark complement involves functional analogues of mammalian C8 and C9. In this article, a full-length cDNA of C9 (CpC9) is identified from cartilaginous species, the whitespotted bambooshark, Chiloscyllium plagiosum by RACE. The CpC9 cDNA is 2263 bp in length, encoding a protein of 603 amino acids, which shares 42% and 43% identity with human and Xenopus C9 respectively. Through sequence alignment and comparative analysis, the CpC9 protein was found well conserved, with the typical modular architecture in TCCs and nearly unanimous cysteine composition from fish to mammal. Phylogenetic analysis places it in a clade with C9 orthologs in higher vertebrate and as a sister taxa to the Xenopus. Expression analysis revealed that CpC9 is constitutively highly expressed in shark liver, with much less or even undetectable expression in other tissues; demonstrating liver is the primary tissue for C9synthesis. To sum up, the structural conservation and distinctive phylogenetics might indicate the potentially vital role of CpC9 in shark immune response, though it remains to be confirmed by further study.

Journal Article

Abstract  The effect of maturation and of two lipid modulators supplementation along in vitro maturation (IVM) on fatty acid (FA) and dimethylacetal (DMA) composition of porcine cumulus oocyte complexes (COC) were studied. Abattoir-derived immature COC were analyzed for FA and DMA or submitted to IVM as follows: control group; t10,c12 CLA group, t10,c12 CLA supplementation for 44 h; Forskolin group, forskolin supplementation during the initial 2 h; t10,c12 CLA + forskolin group, t10,c12 CLA for 44 h and forskolin for just 2h. Each experimental group had five replicates. FA analysis of oocytes, cumulus cells (CC), follicular fluid, and culture media were performed by gas-liquid chromatography. Oocytes and their CC had different FA composition. Oocytes were richer in saturated FA (SFA) preferentially maintaining their FA profile during maturation. Mature CC had the highest polyunsaturated FA (PUFA) content. Five individual and total SFA, and monounsaturated FA (MUFA), notably oleic acid (c9-18:1), percentages were lower (P ≤ 0.023) in mature than in immature CC. t10,c12 CLA was accumulated by COC from t10,c12 CLA and t10,c12 CLA + forskolin groups, mostly in CC where MUFA and an eicosatrienoic isomer decreased (P ≤ 0.043). Nevertheless, PUFA or FA and DMA total content were not affected. Arachidonic acid was reduced in t10,c12 CLA + forskolin CC and hexadecanal-DMA-16:0 in t10,c12 CLA CC. Forskolin alone increased (P ≤ 0.043) c9-18:1 in oocytes. In conclusion, maturation process clearly changed porcine COC FA and DMA profiles, mostly of CC, also more susceptible to modifications induced by t10,c12 CLA. This possibility of manipulating COC lipid composition during IVM could be used to improve oocyte quality/cryopreservation efficiency.

Journal Article

Abstract  Streptococcus pyogenes is an important human pathogen that causes invasive diseases such as necrotizing fasciitis, sepsis, and streptococcal toxic shock syndrome. We investigated the function of a major cysteine protease from S. pyogenes that affects the amount of C1-esterase inhibitor (C1-INH) and other complement factors and aimed to elucidate the mechanism involved in occurrence of streptococcal toxic shock syndrome from the aspect of the complement system. First, we revealed that culture supernatant of a given S. pyogenes strain and recombinant SpeB degraded the C1-INH. Then, we determined the N-terminal sequence of the C1-INH fragment degraded by recombinant SpeB. Interestingly, the region containing one of the identified cleavage sites is not present in patients with C1-INH deficiency. Scanning electron microscopy of the speB mutant incubated in human serum showed the abnormal superficial architecture and irregular oval structure. Furthermore, unlike the wild-type strain, that mutant strain showed lower survival capacity than normal as compared with heat-inactivated serum, whereas it had a significantly higher survival rate in serum without the C1-INH than in normal serum. Also, SpeB degraded multiple complement factors and the membrane attack complex. Flow cytometric analyses revealed deposition of C9, one of the components of membrane the attack complex, in greater amounts on the surface of the speB mutant, whereas lower amounts of C9 were bound to the wild-type strain surface. These results suggest that SpeB can interrupt the human complement system via degrading the C1-INH, thus enabling S. pyogenes to evade eradication in a hostile environment.

Journal Article

Abstract  UNLABELLED: The aim of the present work was to test the potential of Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) in the diagnosis of liver cirrhosis and the assessment of disease severity by direct analysis of exhaled breath. Twenty-six volunteers have been enrolled in this study: 12 patients (M/F 8/4, mean age 70.5 years, min-max 42-80 years) with liver cirrhosis of different etiologies and at different severity of disease and 14 healthy subjects (M/F 5/9, mean age 52.3 years, min-max 35-77 years). Real time breath analysis was performed on fasting subjects using a buffered end-tidal on-line sampler directly coupled to a PTR-ToF-MS. Twelve volatile organic compounds (VOCs) resulted significantly differently in cirrhotic patients (CP) compared to healthy controls (CTRL): four ketones (2-butanone, 2- or 3- pentanone, C8-ketone, C9-ketone), two terpenes (monoterpene, monoterpene related), four sulphur or nitrogen compounds (sulfoxide-compound, S-compound, NS-compound, N-compound) and two alcohols (heptadienol, methanol). Seven VOCs (2-butanone, C8-ketone, a monoterpene, 2,4-heptadienol and three compounds containing N, S or NS) resulted significantly differently in compensate cirrhotic patients (Child-Pugh A; CP-A) and decompensated cirrhotic subjects (Child-Pugh B+C; CP-B+C). ROC (Receiver Operating Characteristic) analysis was performed considering three contrast groups: CP vs CTRL, CP-A vs CTRL and CP-A vs CP-B+C. In these comparisons monoterpene and N-compound showed the best diagnostic performance.

CONCLUSIONS: Breath analysis by PTR-ToF-MS was able to distinguish cirrhotic patients from healthy subjects and to discriminate those with well compensated liver disease from those at more advanced severity stage. A breath-print of liver cirrhosis was assessed for the first time.

Journal Article

Abstract  Acquisition of the complement inhibitor vitronectin (Vn) is important for the respiratory tract pathogen nontypeable Haemophilus influenzae (NTHi) to escape complement-mediated killing. NTHi actively recruits Vn, and we previously showed that this interaction involves Protein E (PE). Here we describe a second Vn-binding protein, a 30 kDa Yersinia YfeA homologue designated as Protein F (PF). An isogenic NTHi 3655Δhpf mutant devoid of PF displayed a reduced binding of Vn, and was consequently more sensitive to killing by human serum compared with the wild type. Surface expression of PF on Escherichia coli conferred binding of Vn that resulted in a serum resistant phenotype. Molecular analyses revealed that the N-terminal of PF (Lys23-Glu48) bound to the C-terminal of Vn (Phe352-Ser374) without disrupting the inhibitory role of Vn on the membrane attack complex. The PF-Vn complex actively delayed C9 deposition on PF-expressing bacteria. Comparative studies of binding affinity and multiple mutants demonstrated that both PE and PF contribute individually to NTHi serum survival. PF was highly conserved and ubiquitously expressed in a series of randomly selected NTHi clinical isolates (n = 18). In conclusion, the multifaceted binding of Vn is beneficial for NTHi survival in serum and may contribute to successful colonization and consequently infection.

Journal Article

Abstract  The potential of heat shock protein 90 (Hsp90) as a therapeutic target for numerous diseases has made the identification and optimization of novel Hsp90 inhibitors an emerging therapeutic strategy. A surface plasmon resonance (SPR) approach was adopted to screen some iridoids for their Hsp90 α binding capability. Twenty-four iridoid derivatives, including 13 new natural compounds, were isolated from the leaves of Tabebuia argentea and petioles of Catalpa bignonioides. Their structures were elucidated by NMR, electrospray ionization mass spectrometry, and chemical methods. By means of a panel of chemical and biological approaches, four iridoids were demonstrated to bind Hsp90 α. In particular, the dimeric iridoid argenteoside A was shown to efficiently inhibit the chaperone in biochemical and cellular assays. Our results disclose C9-type iridoids as a novel class of Hsp90 inhibitors.

Journal Article

Abstract  Dietary conjugated linoleic acids (CLA) are fatty acid isomers with anticancer activities produced naturally in ruminants or from vegetable oil processing. The anticancer effects of CLA differ upon the cancer origin and the CLA isomers. In this study, we carried out to precise the effects of CLA isomers, c9,t11 and t10,c12 CLA, on mechanisms of cell death induction in colon cancer cells. We first showed that only t10,c12 CLA treatment (25 and 50μM) for 72h triggered apoptosis in colon cancer cells without affecting viability of normal-derived colon epithelial cells. Exposure of colon cancer cells to t10,c12 CLA activated ER stress characterized by induction of eIF2α phoshorylation, splicing of Xbp1 mRNA and CHOP expression. Furthermore, we evidenced that inhibition of CHOP expression and JNK signaling decreased t10,c12 CLA-mediated cancer cell death. Finally, we showed that CHOP induction by t10,c12 CLA was dependent on ROS production and that the anti-oxidant N-acetyl-cysteine reduced CHOP induction-dependent cell death. These results highlight that t10,c12 CLA exerts its cytotoxic effect through ROS generation and a subsequent ER stress-dependent apoptosis in colon cancer cells.

Journal Article

Abstract  Increased amounts of reactive oxygen species (ROS) have been implicated in many pathological conditions, including cancer. The major machinery that the cell employs to neutralize excess ROS is through the activation of the antioxidant-response element (ARE) that controls the activation of many phase II detoxification enzymes. The transcription factor that recognizes the ARE, Nrf2, can be activated by a variety of small molecules, most of which contain an α,β-unsaturated carbonyl system. In the pursuit of chemopreventive agents from marine organisms, we built, fractionated, and screened a library of 30 field-collected eukaryotic algae from Florida. An edible green alga, Ulva lactuca, yielded multiple active fractions by ARE-luciferase reporter assay. We isolated three monounsaturated fatty acid (MUFA) derivatives as active components, including a new keto-type C18 fatty acid (1), the corresponding shorter chain C16 acid (2), and an amide derivative (3) of the C18 acid. Their chemical structures were elucidated by NMR and mass spectrometry. All three contain the conjugated enone motif between C7 and C9, which is thought to be responsible for the ARE activity. Subsequent biological studies focused on 1, the most active and abundant ARE activator isolated. C18 acid 1 induced the expression of ARE-regulated cytoprotective genes, including NAD(P)H:quinone oxidoreductase 1, heme oxygenase 1, thioredoxin reductase 1, both subunits of the glutamate-cysteine ligase (catalytic subunit and modifier subunit), and the cystine/glutamate exchange transporter, in IMR-32 human neuroblastoma cells. Its cellular activity requires the presence of Nrf2 and PI3K function, based on RNA interference and pharmacological inhibitor studies, respectively. Treatment with 1 led only to Nrf2 activation, and not the increase in production of NRF2 mRNA. To test its ARE activity and cytoprotective potential in vivo, we treated mice with a single dose of a U. lactuca fraction that was enriched with 1, which showed ARE-activating effects similar to those observed in vitro. This could be owing to this fraction's ability to stabilize Nrf2 through inhibition of Keap1-mediated Nrf2 ubiquitination and the subsequent accumulation and nuclear translocation of Nrf2. The induction of many ARE-driven antioxidant genes in vivo and most prominently in the heart agreed with the commonly recognized cardioprotective properties of MUFAs. A significant increase in Nqo1 transcript levels was also found in other mouse tissues such as the brain, lung, and stomach. Collectively, this study provides new insight into why consumption of dietary seaweed may have health benefits, and the identified compounds add to the list of chemopreventive dietary unsaturated fatty acids.

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