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Inhibition of COX and LOX could contribute to memory formation and prevention of neurodegeneration, by alleviation of neuroinflammation and improvement of mitochondrial homeostasis. We aimed to assess the effect of licofelone, a dual COX and 5-LOX inhibitor on memory formation, neural apoptosis, neural regeneration, and mitophagy in acute and chronic dosages, given that licofelone could regulate nitric oxide levels. Y-maze and Passive Avoidance tests were used to evaluate memory function in NMRI mice using the EthoVision setting, following scopolamine administration (1 mg/kg, i.p.) as an acute amnestic drug. Hippocampi were used to evaluate the levels of apoptosis via TUNEL assay, neural regeneration via immunohistochemistry method detecting doublecortin and nestin, and mitophagy via Western blot of mitophagy proteins Parkin and ATG5. While acute high-dose licofelone (20 mg/kg) could reverse amnestic effects of scopolamine in passive avoidance test (p = 0.0001), Chronic licofelone (10 mg/kg for 10 consecutive days) could improve performance in Y-maze (p = 0.0007). Molecular analysis revealed that the chronic form of the drug could enhance neural regeneration in CA1 and SGZ regions, reset mitophagy levels as much as the healthy state, and reduce apoptosis rate. Licofelone appears to show a desirable anti-amnestic profile in a low dose chronically; it is hence recommended for future clinical studies on the prevention of neuroinflammation and memory deficit. [ABSTRACT FROM AUTHOR]

Jujube (Ziziphus jujuba Mill.) is a traditional popular fruit widely grown in China. The volatiles in jujube determine its unique flavor and the high fruit quality required by consumers. However, the biosynthesis of volatiles in jujube were remain unknown. By using gas chromatography–mass spectrometry, there were 46 volatile compounds were identified and determined from three representative jujube fruit types at six developmental stages, including the dry-used (Z. jujuba cv. 'Junzao'), the fresh-used (Z. jujuba cv. 'Dongzao'), and wild jujube (Z. jujuba var. spinosa Hu. cv. 'Qingjiansuanzao'). The aldehydes were identified as major volatile contributors to flavor, of which (E)-2-hexenal was the primary volatile in jujube fruit. Then LOX and HPL gene family were identified in jujube, which were involved in aldehyde biosynthesis through the lipoxygenase-hydroperoxide lyase (LOX-HPL) pathway. Gene expression analysis suggested that ZjLOX3 , ZjLOX4 , and ZjHPL1 were highly correlated with the accumulation of (E)-2-hexenal, and their proteins were localized to the nucleus and cytoplasm. Transient over-expression of ZjLOX3 , ZjLOX4 , and ZjHPL1 in jujube fruit significantly enhanced the accumulation of (E)-2-hexenal. Our study provides valuable information on the major volatiles and their biosynthesis in different types of jujube fruit. These results will help determine flavor improvements for future breeding. [ABSTRACT FROM AUTHOR]

Ethylene plays a critical role in peach (Prunus persica) fruit ripening; however, the molecular mechanism underlying ethylene-mediated aroma biosynthesis remains unclear. Here, we compared the difference in aroma-related volatiles and gene expression levels between melting-flesh (MF) and stony hard (SH) peach cultivars at S3, S4 I, S4 II, S4 III stages, and explored the relation between volatile biosynthesis related genes and ethylene response factor (ERF) genes. The concentration of fruity aromatic compounds such as lactones and terpenes increased significantly in MF peach during fruit ripening, while it was nearly undetectable in SH peach. LOX4 and FAD1 genes expressed concomitantly with ethylene emission and significantly downregulated by 1-MCP. Besides, 1-MCP treatment could sharply influence the fruity aromatic compounds, suggesting that these genes play key roles in volatile biosynthesis during fruit ripening. Furthermore, PpERF5 and PpERF7 could bind together to form a protein complex that enhanced the transcription of LOX4 more than each transcription factor individually. Overall, this work provides new insights into the transcriptional regulatory mechanisms associated with aroma formation during peach fruit ripening. • Lactones and terpenes increased sharply in MF peach, but undetectable in SH peach. • LOX4 and FAD1 genes were expressed concomitantly with ethylene emission. • PpERF5 and PpERF7 could bind together that enhanced the transcription of LOX4. [ABSTRACT FROM AUTHOR]

• LOX (but not LOXL2) promotes breast cancer metastatic osteolytic lesions in vivo. • LOX (but not LOXL2) enhances RANKL-induced osteoclast differentiation in vitro. • LOX (but not LOXL2) induces a robust IL-6 production by tumor cells in vitro. The primary function of the lysyl oxidase (LOX) family, including LOX and its paralogue LOX-like (LOXL)-2, is to catalyze the covalent crosslinking of collagen and elastin in the extracellular matrix. LOX and LOXL2 are also facilitating breast cancer invasion and metastatic spread to visceral organs (lungs, liver) in vivo. Conversely, the contribution of LOX and LOXL2 to breast cancer bone metastasis remains scant. Here, using gene overexpression or silencing strategies, we investigated the role of LOX and LOXL2 on the formation of metastatic osteolytic lesions in animal models of triple negative breast cancer. In vivo , the extent of radiographic metastatic osteolytic lesions in animals injected with LOX-overexpressing [LOX(+)] tumor cells was 3-fold higher than that observed in animals bearing tumors silenced for LOX [LOX(−)]. By contrast, the extent of osteolytic lesions between LOXL2(+) and LOXL2(−) tumor-bearing animals did not differ, and was comparable to that observed with LOX(−) tumor-bearing animals. In situ , TRAP staining of bone tissue sections from the hind limbs of LOX(+) tumor-bearing animals was substantially increased compared to LOX(−), LOXL2(+) and LOXL2(−)-tumor-bearing animals, which was indicative of enhanced active-osteoclast resorption. In vitro , tumor-secreted LOX increased osteoclast differentiation induced by RANKL, whereas LOXL2 seemed to counteract LOX's pro-osteoclastic activity. Furthermore, LOX (but not LOXL2) overexpression in tumor cells induced a robust production of IL-6, the latter being a pro-osteoclastic cytokine. Based on these findings, we propose a model in which LOX and IL-6 secreted from tumor cells act in concert to enhance osteoclast-mediated bone resorption that, in turn, promotes metastatic bone destruction in vivo. [ABSTRACT FROM AUTHOR]

Copper was reported to be involved in the onset and progression of cancer. Proteins in charge of copper uptake and distribution, as well as cuproenzymes, are altered in cancer. More recently, proteins involved in signaling cascades, regulating cell proliferation, and anti-apoptotic protein factors were found to interact with copper. Therefore, therapeutic strategies using copper complexing molecules have been proposed for cancer therapy and used in clinical trials. This review will focus on novel findings about the involvement of copper and cupro-proteins in cancer dissemination process, epithelium to mesenchymal transition and vascularization. Particularly, implication of well-established (e.g. lysil oxidase) or newly identified copper-binding proteins (e.g. MEMO1), as well as their interplay, will be discussed. Moreover, we will describe recently synthesized copper complexes, including plant-derived ones, and their efficacy in contrasting cancer development. The research on the involvement of copper in cancer is still an open field. Further investigation is required to unveil the mechanisms involved in copper delivery to the novel copper-binding proteins, which may identify other possible gene and protein targets for cancer therapy. [ABSTRACT FROM AUTHOR]

Inflammation is implicated in the pathogenesis of many diseases such as Alzheimer's disease, rheumatoid arthritis and cancer. Inflammation is a complex process, involving the activation of specific mediators such as enzymes, cytokines, as well as growth and nuclear factors. The inhibition of pro-inflammatory enzymes is regarded as an effective strategy to combat inflammation. The undesirable side effects associated with many current anti-inflammation drugs have necessitated an increased search for natural principles with the capacity to suppress or inhibit inflammation mediators and with much reduced side effects. South Africa has a rich floral biodiversity coupled with indigenous knowledge systems on the use of medicinal plants, which has become widely explored for meeting primary health care needs, especially in resource-limited areas. Using electronic search engines and library resources, this review highlights the successes, challenges and prospects associated with the exploration of the South African floral diversity for inflammatory inhibitors. Several South African plant extracts demonstrated pro-inflammatory enzyme inhibitory potential with very low cytotoxicity. However, these reports have been based largely on in vitro evaluation. This has resulted in, at least, partial valorisation of their traditional uses. Notwithstanding the vast natural endowment and the available technology in bioprospecting the floral diversity for natural inflammatory enzyme inhibitors, only a limited number of plant species has been exploited and a relatively negligible fraction has been developed into natural products. The current limited bioprospecting 'success', when examined in the light of relatively untapped opportunity, underscores the potential for the discovery of new sources of natural inflammatory enzyme inhibitors. • Partial valorisation of South African plants for inflammatory inhibition. • Strong COX-inhibitory activity demonstrated largely in in vitro -based assays. • Potential to search for inhibitors of COX-2, LOX, sPLA2 and iNOs enzymes. [ABSTRACT FROM AUTHOR]

Impaired function of the endoplasmic stress (ER) response causes numerous pathological conditions, including tissue fibrosis. In the present study, we aimed to determine the pathological role of ER stress response systems in myeloproliferative neoplasms (MPNs). We found increased expression of the chaperone protein glucose-regulated protein (GRP) 78, a central regulator of ER stress, in megakaryocytes from primary myelofibrosis or postessential thrombocythemia myelofibrosis patients. GRP78 was overexpressed in JAK2V617F-harboring cell lines; however, inhibitors of ER stress did not affect the expression levels of GRP78. In contrast, ruxolitinib, a well-known inhibitor of JAK2V617F, clearly blocked GRP78 expression in these cells through downregulation of transcription factor 4 (ATF4). Interestingly, GRP78 was secreted from HEL and SET-2 cells into culture media. Coculture of these cells with HS-5 cells, a human bone marrow stroma-derived cell line, induced enhanced expression of lysyl oxidase (LOX), which mediates cross-linking of collagen fibers and induces tissue fibrosis, in HS-5 cells. An anti-GRP78 neutralizing antibody abrogated LOX elevation; in contrast, recombinant GRP78 protein induced LOX protein expression in HS-5 cells. Our observations suggest that the oncogenic protein JAK2V617F induces overexpression and release of GRP78, which may induce a fibrotic phenotype in surrounding bone marrow stromal cells. • GRP78, an endoplasmic response regulating chaperon is overexpressed in primary megakaryocytes derived from PMF or secondary MF patients. • JAK2V617F induced overexpression of GRP78 through activation of transcription factor ATF4. • JAK2V617F harboring HEL and SET-2 cells secreted GRP78 into microenvironment. • Secreted GRP78 work on bone marrow stromal cell line to activate JNK pathway leading to expression of lysyl oxidase. • Overexpression of lysyl oxidase in stromal cells were found in bone marrow biopsy specimens from PMF or secondary MF patients. [ABSTRACT FROM AUTHOR]

Abstract Lipoxygenases (LOXs) (EC 1.13.11.12) catalyze the oxygenation of fatty acids and produce oxylipins including the plant hormone jasmonate (jasmonic acid/methyl jasmonate; MeJA). Little is known about the tomato LOX gene family members that impact tomato growth and development, and less so about their feed-back regulation in response to MeJA. We present genome wide identification of 14 LOX gene family members in tomato which map unevenly on 12 chromosomes. The characteristic structural features of 9-LOX and 13-LOX tomato gene family, their protein domains/features, and divergence are presented. Quantification of the expression patterns of all the 14 SlLOX gene members segregated the members based on differential association with growth, development, or fruit ripening. We also identified those SlLOX genes whose transcription responds to exogenous MeJA and/or wounding stress. MeJA-based feedback regulation that involves activation of specific members of LOX genes is defined. Specific nature of SlLOX gene regulation in tomato is defined. The novel data on dynamics of SlLOX gene expression should help catalyze future strategies to elucidate role(s) of each gene member in planta and for crop biotechnological intervention. [ABSTRACT FROM AUTHOR]

2,4-dichlorophenoxyacetic acid (2,4-D) is among the most commonly used herbicides applied for weed control during wheat cultivation. However, its application could affect wheat growth. The present study investigates the effect of the ascomycetous fungus Trichoderma harzianum on lipid peroxidation, phospholipids, signaling lipids and phospholipase D in the seedlings of wheat ( Triticum aestivum L .) treated with 2,4-D (2.5 mg L −1 ). In the group of 4-day-old seedlings exposed to the herbicide, increased lipid peroxidation and inhibition of growth were observed in shoots and roots. Moreover, elevated levels of oxylipins were noted. Among them, the amount of 13-HOTrE oxygenated from linolenic acid (18:3) increased the most significantly. Concurrently, in the seedlings inoculated with T. harzianum , growth was stimulated when the level of phosphatidylcholine (PC) increased. Moreover, in wheat seedlings treated with 2,4-D and T. harzianum , the level of lipid peroxidation was similar to that in the control and there was no increase observed in oxylipins and phospholipase D activity. T. harzianum might have partly alleviated the toxic effect of 2,4-D on wheat seedlings. [ABSTRACT FROM AUTHOR]

Summary Breast cancer cells relocate to bone and activate osteoclast-induced bone resorption. Soluble factors secreted by breast cancer cells trigger a cascade of events that stimulate osteoclast differentiation in the bone microenvironment. MacroH2A is a unique histone variant with a C-terminal non-histone domain and plays a crucial role in modulating chromatin organization and gene transcription. Here, we show that macroH2A1.2, one of the macroH2A isoforms, has an intrinsic ability to inhibit breast cancer-derived osteoclastogenesis. This repressive effect requires macroH2A1.2-dependent attenuation of expression and secretion of lysyl oxidase (LOX) in breast cancer cells. Furthermore, our mechanistic studies reveal that macroH2A1.2 physically and functionally interacts with the histone methyltransferase EZH2 and elevates H3K27me3 levels to keep LOX gene in a repressed state. Collectively, this study unravels a role for macroH2A1.2 in regulating osteoclastogenic potential of breast cancer cells, suggesting possibilities for developing therapeutic tools to treat osteolytic bone destruction. [ABSTRACT FROM AUTHOR]

Fibrotic extracellular matrix (ECM) remodeling characterized different types of pulmonary fibrosis, and its regulation could be a potential shared treatment strategy for pulmonary fibrosis. We aimed to investigate the effect of triptolide on pulmonary fibrosis through the inhibition of several important aspects of fibrotic ECM remodeling. Bleomycin-induced pulmonary fibrosis mice and TGF-β 1 -induced primary lung fibroblasts were used. The effect of triptolide on pulmonary fibrosis was detected using histopathology, immunostaining, RT-qPCR, western blotting, ELISA, and protein activity assay. Triptolide significantly alleviated bleomycin-induced pulmonary fibrosis in mice. It inhibited the expression of fibrotic genes α-SMA, collagen I, fibronectin, and vimentin and blocked the TGF-β-SMAD signaling pathway both in vivo and in vitro. In addition, triptolide regulated the expression and activity of MMPs during fibrosis. Interestingly, it suppressed the expression of lysyl oxidase, which was responsible for matrix cross-linking and elevated ECM stiffness. Furthermore, triptolide blocked the biomechanical stress transduction pathway integrin-β1-FAK-YAP signaling and attenuated the pro-fibrotic feedback of fibrotic ECM on fibroblasts via integrin inhibition. These findings show that triptolide prevents the key linkages of fibrotic ECM remodeling, including deposition, degradation, cross-linking, and pro-fibrotic feedback and, therefore, has potential therapeutic value for pulmonary fibrosis. [Display omitted] • Triptolide ameliorated fibrotic ECM deposition in bleomycin-induced pulmonary fibrosis and TGF-β1-induced myofibroblasts. • Triptolide blocked TGF-β-SMAD signaling pathway both in vivo and in vitro. • Triptolide inhibit fibrotic ECM remodeling in degradation and cross-linking mediated by MMPs and LOX. • Triptolide inhibited integrin-FAK-YAP1 dependent pro-fibrotic feedback of ECM to fibroblasts. [ABSTRACT FROM AUTHOR]

The spectral qualities of light contain environmental information used by plants as cues to modify their biology in order to adapt and survive. LED based lamps, with their highly definable spectral properties, thus hold great perspectives for use in greenhouse production. The effects of the spectral qualities of light on plant physiology is still not fully understood, and a great fraction of the current knowledge further comes from studies looking at short term effects or using monochromatic light treatments in enclosed growth chambers, thus far from the light conditions of greenhouse production. The objective of this study was to determine whether spectral modifications to the supplemental LED lighting in greenhouse production could modify post-cultivation performance of basil, which is prone to chilling injuries (CI). We cultivated basil under greenhouse conditions using four different supplemental LED light treatments; 80%Red/20%Blue, 80%Red/20%Blue + UV-A, 40%Red/60%Blue and 80%Red/20%Green, followed by a post-cultivation shelf life simulation including a chilling treatment. Stomatal anatomical features and levels of hormonal regulators, abscisic acid (ABA) and ABA glucosylester (ABA-GE), along with soluble sugars, fatty acids and lipoxygenase activity (LOX) were determined at the end of the growing period. Without compromising grow rates, the light treatments showed marked effects on the chilling tolerance and shelf life performance with increasing ratios of blue light having negative effects, and green light having positive effects on chilling tolerance. Differences in shelf life performance seemed mediated solely by factors related to stomatal functioning. Stomatal density (number of stomata per leaf area, SD) increased with increasing ratios of blue light whereas green light showed indications to decrease SD. [ABA] and [ABA-GE] showed positive correlation to SD, whereas the ratio of [ABA-GE]/[ABA] conversely correlated negatively with increased SD. Our results thus suggest an important relationship between leaf water retention and post-cultivation chiling tolerance in basil. [ABSTRACT FROM AUTHOR]

Metastasis stands as the major obstacle for the survival from cancers. Nonetheless most existing anti-cancer drugs inhibit only cell proliferation, and discovery of agents having both anti-proliferative and anti-metastatic properties would be more beneficial. We previously reported the discovery of small-molecule Ras inhibitors, represented by Kobe0065, that displayed anti-proliferative activity on xenografts of human colorectal cancer (CRC) cell line SW480 carrying the K-rasG12Vgene. Here we show that treatment of cancer cells carrying the activated ras genes with Kobe0065 or a siRNA targeting Ras downregulates the expression of lysyl oxidase (LOX), which has been implicated in metastasis. LOX expression is enhanced by co-expression of RasG12V through activation of phosphatidylinositol 3-kinase (PI3K)/Akt and concomitant accumulation of hypoxia-inducible factor (HIF)-1α. Furthermore, Kobe0065 effectively inhibits not only migration and invasion of cancer cells carrying the activated ras genes but also lung metastasis of human CRC cell line SW620 carrying the K-rasG12V gene. Collectively, these results indicate that Kobe0065 prevents metastasis through inhibition of the Ras-PI3K-Akt-HIF-1α-LOX signaling and suggest that Ras inhibitors in general might exhibit both anti-proliferative and anti-metastatic properties toward cancer cells carrying the activated ras genes. [ABSTRACT FROM AUTHOR]

Abnormalities in the elastic fiber biology are seen in pulmonary emphysema (PE). The copper-dependent lysyl oxidases regulate the production and accumulation of elastic fibers in the connective tissue. This study focused on the relationship between lysyl oxidase (LOX), LOX-like protein 1 (LOXL1), and LOXL2 and PE pathogenesis. Lung samples with or without PE from patients with chronic obstructive lung disease (n = 35) were used. Protein levels of elastin, LOX, LOXL1, LOXL2, hypoxia inducible factor 1-alpha (HIF-1α), copper metabolism domain containing-1 (COMMD1), and phosphatase and tensin homolog (PTEN) were assayed using microscopic and biochemical methods The emphysematous areas were characterized by enlargement of the alveoli, destruction of the alveolar structure, accumulation of macrophages in the alveolar lumens, and showed increased HIF-1α immunoreactivity. Additionally, the emphysematous areas had significantly lower elastin, LOX, LOXL1, LOXL2, HIF-1α, COMMD1, and PTEN protein levels than the non-emphysematous areas. We suppose that the reductions in the HIF-1α levels led to decreases in the protein levels of active LOX, LOXL1, and LOXL2. These decreases might cause abnormalities in the elastic fiber biology. HIF-1α activation induced by decreased COMMD1 and protease activation induced by decreased PTEN might contribute to the development of PE. Finally, methods aimed at increasing the protein levels of LOXs, COMMD1 and PTEN might be effective for treating PE. [ABSTRACT FROM AUTHOR]

Lysyl oxidase (LOX) is an extra-cellular matrix-modifying enzyme that has been linked to cell proliferation, metastasis, angiogenesis and wound healing. This study was designed to examine the association of LOX gene polymorphism G473A, G > A, (rs1800449) located in exon 1 of the LOX gene in diabetic subjects with and without diabetic foot ulcers (DFU) and its impact of expression on DFU. Genotypic analysis of 906 samples showed a significant increase in the presence of ‘A' allele in type 2 diabetes mellitus (T2DM) and DFU when compared to that of control subjects. Allele wise analysis showed a higher frequency of ‘A’ allele in the T2DM (36.23%, OR 1.069, P value 0.29) and DFU (41.69%, OR 1.195, P value 0.003) when compared to that of control subjects (33.17%). Interestingly, real time RT-PCR results showed significant increased transcript level of the LOX gene on the AA genotype of DFU when compared to that of the AA genotype of T2DM and control subjects. Our finding predicts that there is an association of LOX gene polymorphism (G473A) on diabetes and DFU patients when compared to that of healthy controls. Thus, this study merits further evaluation on a mechanistic approach of this gene. [ABSTRACT FROM AUTHOR]

A series of novel quinoline-2-carboxamides 15 – 28 was synthesized and evaluated in vitro as dual COXs/LOX inhibitors. Compounds 19 and 27 exhibited the highest potency and selectivity for COX-2 inhibitory activity (IC 50 = 1.21 and 1.13 μM, respectively; selectivity index (COX-1/COX-2) = 6.52 and 7.61, respectively) in comparison to the reference drug celecoxib (COX-2 IC 50 = 0.88 μM; selectivity index (COX-1/COX-2) = 8.31). The anti-inflammatory activity of the newly synthesized compounds was further assessed in vivo using carrageenan induced paw edema assay. Interestingly, the in vitro results of COXs inhibitory assay were consistent with that of the in vivo assay where compounds 19 and 27 showed the highest anti-inflammatory activity with edema inhibition percentages of 59.38% and 65.03%, respectively compared to celecoxib (71.21%) after 5 h. Moreover, it was found that compounds 19 and 27 have a superior gastric safety profile comparable to indomethacin. The molecular docking study of compounds 19 and 27 into COX-2 active site suggested that these hits assumed binding pattern and interactions similar to that of bromocelecoxib (S-58) as a cocrystallized ligand explaining their remarkable COX-2 inhibitory activity and selectivity. Taken together, these results indicated that these derivatives are good leads for subsequent development into potential anti-inflammatory agents with least gastric damage. [ABSTRACT FROM AUTHOR]

• ERRγ up-regulates LOX gene expression in mouse hepatocytes. • Pro-inflammatory cytokine, IL6 induces LOX gene expression through ERRγ. • The specific inverse agonist of ERRγ inhibits IL6-induced LOX gene expression. Lysyl oxidase (LOX), the copper-dependent extracellular enzyme, plays a critical role in the regulation of protein cross-linking in the extracellular matrix (ECM). It is also involved in liver regeneration and liver fibrosis. However, the mechanism of LOX regulation in mouse hepatocytes is still unclear. Here, we identify a molecular mechanism showing that orphan nuclear receptor estrogen-related receptor γ (ERRγ) regulates LOX gene expression in the presence of the pro-inflammatory cytokine, interleukin 6 (IL6). IL6 significantly stimulated the expression of ERRγ and LOX in mouse hepatocytes. Overexpression of ERRγ increased LOX mRNA and protein levels. Moreover, knockdown of ERRγ attenuated IL6-mediated LOX gene expression at mRNA and protein levels. Overexpression of ERRγ or IL6 treatment upregulated LOX gene promoter activity, while knockdown of ERRγ decreased the IL6-induced LOX promoter activity. Furthermore, GSK5182, a specific ERRγ inverse agonist, inhibited the induction effect of IL6 on LOX promoter activity and gene expression in mouse hepatocytes. Overall, our study elucidates the mechanism involved in the LOX gene regulation by nuclear receptor ERRγ in response to IL6 in mouse hepatocytes, suggesting that, in conditions such as chronic inflammation, IL6 may contribute to liver fibrosis via inducing LOX gene expression. Thus, LOX gene regulation by the inverse agonist of ERRγ can be applied to improve liver fibrosis. [ABSTRACT FROM AUTHOR]

Lysyl oxidase (LOX) is an essential enzyme for the stabilization of the extracellular matrix (ECM) and the subsequent follicle and oocyte maturation. Currently, there is limited information pertaining to the regulation of LOX activity in human ovarian tissue. Growth differentiation factor 8 (GDF8) is a unique member of the transforming growth factor-β superfamily that is expressed in human granulosa cells and has important roles in regulating a variety of ovarian functions. The aim of the present study was to investigate the effects of GDF8 on the regulation of LOX expression and activity in human granulosa cells and to examine the underlying molecular determinants. An established immortalized human granulosa cell line (SVOG) and primary granulosa-lutein cells were used as study models. Using dual inhibition approaches (TGF-β type I inhibitor SB505124 and small interfering RNAs) and ChIP analyses, we have demonstrated that GDF8 up-regulated the expression of connective tissue growth factor (CTGF) through the activin receptor-like kinase 5-mediated SMAD2/3-SMAD4 signaling pathways. In addition, the increase in CTGF expression contributed to the GDF8-induced increase in LOX expression and activity. Our findings suggest that GDF8 and CTGF may play critical roles in the regulation of ECM formation in human granulosa cells. [ABSTRACT FROM AUTHOR]

Osteoblast and osteoclast communication ( i.e. osteocoupling) is an intricate process, in which the biophysical profile of bone ECM is an aggregate product of their activities. While the effect of microenvironmental cues on osteoblast and osteoclast maturation has been resolved into individual variables ( e.g. stiffness or topography), a single cue can be limited with regards to reflecting the full biophysical scope of natural bone ECM. Additionally, the natural modulation of bone ECM, which involves collagenous fibril and elastin crosslinking via lysyl oxidase, has yet to be reflected in current synthetic platforms. Here, we move beyond traditional substrates and use cell-derived ECM to examine individual and coupled osteoblast and osteoclast behavior on a physiological platform. Specifically, preosteoblast-derived ECM is crosslinked with genipin, a biocompatible crosslinker, to emulate physiological lysyl oxidase-mediated ECM crosslinking. We demonstrate that different concentrations of genipin yield changes to ECM density, stiffness, and roughness while retaining biocompatibility. By approximating various bone ECM profiles, we examine how individual and coupled osteoblast and osteoclast behavior are affected. Ultimately, we demonstrate an increase in osteoblast and osteoclast differentiation on compact and loose ECM, respectively, and identify ECM crosslinking density as an underlying force in osteocoupling behavior. [ABSTRACT FROM AUTHOR]

Ripening in intact apple fruit is accompanied by an increase in the autonomous emissions of hexanol and esters derived from hexanol (hexyl esters). It is thought that these compounds are, to some extent, dependent upon hexanal synthesis by the action of lipoxygenase (LOX) on fatty lipids. To better understand the relationship between fatty acid substrates and their volatile products, we determined the content of oleic (18:1), linoleic (18:2), and linolenic (18:3) acids in free and polar (esterified) lipid fractions of the skin and subtending cortex of ‘Jonagold’ fruit throughout ripening. In the free fatty acid fraction, 18:1 and 18:2 content increased several-fold during ripening, but the 18:3 content remained low and unchanged. In the polar lipid fraction, ripening resulted in a modest increase in the 18:1 and 18:2 content and an extensive decline in the 18:3 content. The rise in 18:2 content of the free fatty acid fraction mirrored emissions of hexanol and hexyl esters in intact fruit and the decline in the 18:3 content of polar lipids reflected the drop in cis -3-hexenal emissions found for disrupted fruit tissue. For intact fruit, our results suggest that hexanal and its metabolites, hexanol and hexyl esters, may be derived from the action of LOX on 18:2 free fatty acid. For disrupted fruit tissue, the data suggest cis -3-hexenal and trans -2-hexenal are largely generated from the action of LOX on 18:3 in the polar lipid fraction. The mechanism whereby free 18:1 and 18:2 could accumulate without a concomitant increase in free 18:3 is not clear. To our knowledge, there is currently no synthetic or catabolic pathway characterized that might account for this finding. [ABSTRACT FROM AUTHOR]

[Display omitted] • A total of 147 volatile compounds in faba bean fractions were identified and quantified. • Protein fractions contained the most volatile compounds and lipoxygenase activity. • Fatty acid oxidation and amino acid degradation were the main origins of volatiles. • 35 odour-active compounds belonging to 12 classes were identified in the 9 fractions. • Odour "profiles" were different according to each cultivar and fraction. Faba bean (Vicia faba L. minor) has many interests but is characterised by off-notes (negative odours/aromas) due to volatile compounds that are promoted during seed processing. Little is known about the volatile compounds of faba bean and their contribution to its odour. The purpose of this study was to determine the volatile compound origins of air-classified fractions (flour (F), starch (S) and protein (P)) from 3 faba bean cultivars and identify the odour-active compounds. Firstly, the volatile content of the fractions was extracted by solvent-assisted flavour evaporation (SAFE) and analysed by gas chromatography-mass spectrometry (GC–MS). A total of 147 volatile compounds were detected and categorised into 12 chemical classes. The P fractions had many volatile compounds from free fatty acid (FFA) oxidation and a higher lipoxygenase (LOX) activity. The volatile content suggested that cultivar 1 (C1) was confronted with a biotic stress at field whereas cultivar 2 (C2), richer in molecules from amino acid (AA) degradation, was contaminated by microorganisms in the field. Secondly, 35 odour-active compounds (OACs) were identified by GC-olfactometry (GC-O) and 12 odour-classes were used to describe the faba bean odours. The P fractions had higher detection frequency (DF) than the S and F fractions. P2 had a more complex odour profile due to important FFA and AA degradation. This work provides a better understanding of the impact of cultivar and processing steps on the faba bean volatile content. Selection of pulse-based ingredients with low volatile compounds could improve their flavour and increase their consumption. [ABSTRACT FROM AUTHOR]

• Newer [1,3,4]-thiadiazoles compounds (7a-j) are synthesized and have been evaluated as XO inhibitor. • Bioactivity were evaluated for inflammatory enzymes using COX and LOX. • Compound (7i) was found to exhibited best activity. • The results were supported by In-silico docking, DFT and MEP surface studies. Xanthine oxidase (XO) is an interesting target for the synergic treatment of several diseases such as gout, hypertension, type 2 diabetes, and kidney disease. Associated complication includes hyperuricemia, which is considered one of the most common metabolic lifestyle disorders worldwide. Overproduction and insufficient excretion of uric acid during purine metabolism results in the formation of uric acid crystals in kidneys, joints, and other tissues. Allopurinol and Febuxostat, a clinically available drug used to reduce XO activity and serum uric acid level, are demonstrated to produce adverse effects including gastrointestinal distress, hypersensitivity, and skin rash, raising safety concerns. Exploring newer and novel XO inhibitors with minimum or no side effects is the aim of the current study. [1,3,4]-Thaidiazole analogs (7a-j) scaffold plays an important role in the design of efficient and potent inhibitors. In the present work, (7a-j) were evaluated for their ability to inhibit XO and found that among the series compound (7i) is selected as the best compound for inhibition of XO. Further, cyclooxygenases (COXs) and 5-lipoxygenase (5-LOX), enzymes that generate biologically active lipid molecules termed eicosanoids, are considered inflammatory and play a vital role in inflammatory pathways in the human body. Apart from their relation with inflammation, the additional involvement of COX-2 enzyme with cancer activity was recently discovered. In some cancer types, the level of COX-2 enzyme is increased indicating that this enzyme could be a suitable target for cancer therapy. Based on these findings, we have synthesized some new novel [1,3,4]-thiadiazole analogous (7a-j) and tested them against XO, COX, and LOX. To gain insight into the activity of XO, COX, and LOX inhibition, molecular docking studies were carried out for XO, COX, and LOX enzymes utilizing the newly synthesized compounds (7a-j) , and the results inferred that among the synthesized series of [1,3,4]-thiadiazoles (7a-j) , the compound (7i) showed extremely good result in both In silico and evaluation studies of XO, COX, and LOX, which is in agreement with the experimental results. Furthermore, density functional theory (DFT) was applied to calculate HOMO-LUMO, energy gap, and other parameters under the hybrid exchange-correlation functional (B3LYP) with the triple split valence basis set (6-311G). [ABSTRACT FROM AUTHOR]

Eicosanoids play an important role in inducing complex and crucial physiological processes in animals. Eicosanoid biosynthesis in animals is widely reported; however, eicosanoid production in invertebrate tissue is remarkably different to vertebrates and in certain respects remains elusive. We, for the first time, compared the orthologs involved in arachidonic acid (AA) metabolism in 14 species of invertebrates and 3 species of vertebrates. Based on parsimony, a complex AA-metabolic system may have existed in the common ancestor of the Metazoa, and then expanded and diversified through invertebrate lineages. A primary vertebrate-like AA-metabolic system via cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome P450 (CYP) pathways was further identified in the basal chordate, amphioxus. The expression profiling of AA-metabolic enzymes and lipidomic analysis of eicosanoid production in the tissues of amphioxus supported our supposition. Thus, we proposed that the ancestral complexity of AA-metabolic network diversified with the different lineages of invertebrates, adapting with the diversity of body plans and ecological opportunity, and arriving at the vertebrate-like pattern in the basal chordate, amphioxus. [ABSTRACT FROM AUTHOR]

Abstract: Two faba bean (Vicia faba L.) subspecies major and minor and lentil seeds grown in Algeria were separated into cotyledons and hulls. These fractions, together with their corresponding whole seeds, were extracted with two solvents, aqueous (70%) acetone and (80%) ethanol, and evaluated for antioxidant activity in relation to their phenolic contents. Acetone selectively extracted tannins from faba beans. The hulls always exhibited high antioxidant activity, measured using the reducing power (RP), antiradical activity (DPPH) or oxygen radical absorbance capacity (ORAC) assays. Aqueous ethanol (80%) extract of lentil hulls exhibited high antioxidant and anti-inflammatory activities preferentially inhibiting 15-LOX (IC50, 55μg/ml), with moderate COX-1 (IC50, 66μg/ml) and COX-2 (IC50, 119μg/ml) inhibitory effects on the COX pathway, whereas faba bean hull extracts exerted relatively mild LOX inhibitory activity. [Copyright &y& Elsevier]

Abstract: Herein, we report the antioxidant properties of some selected substituted 2-indolyl carbohydrazides (JL34, JL40, JL71, JL87, JL317, JL432, JL436), the substituted 3-indolyl carbohydrazide JL344, 3-(3-hydrazinylpropyl)-1H-indole (JL72) and 3-(1H-indol-3-yl)propanehydrazide (JL418), throughout the assessment of their antioxidative potential using different antioxidant assays such as DPPH, lipid peroxidation in the APPH, or the DMSO method. We conclude that these compounds are convenient templates for the design of useful drugs in to treat Alzheimer's disease (AD), a pathology characterized by extensive oxidative stress and inflammation, thus essentially affected by reactive oxygen species (ROS). Most of them are potent hydroxyl radical scavengers and inhibit in vitro lipid peroxidation. Compounds JL40 and JL432 presenting higher lipoxygenase inhibitory activity among the tested derivatives, were found to present a promising anti-inflammatory in vivo result, as well as antioxidant and LOX inhibitory profile. These results in combination to their known AChE/BuChE inhibitory activities led us to propose these indolyl carbohydrazides as new multifunctional compounds against AD. [Copyright &y& Elsevier]

Abstract: To minimise lipid oxidation and maintain high carotenoid and tocol concentrations in wheat flours and products, fifty-seven accessions, belonging to different Triticum species (Triticum monococcum, Triticum turgidum and Triticum aestivum), were assessed for lipoxygenase activity. The highest enzymatic activity was observed in T. aestivum (8.02±0.492μmol/min/g DM), followed by T. turgidum (3.48±0.701) and by T. monococcum (0.45±0.072). While the lipoxygenase was consistently high amongst T. aestivum and steadily low amongst T. monococcum samples, the T. turgidum accessions clustered in three different groups, with low (0.12–0.91μmol/min/g DM), medium (3.10–4.17) and high (5.57–9.51) activity. Enzymatic activity was maximum in the pH range 5–6. LOX activity was higher in the germ (206μmol/min/g DM), than in the bran (13.4) or in the endosperm (3.1). The results demonstrate that the selection of genotypes with low LOX, a factor limiting oxidative degradation, is feasible. [Copyright &y& Elsevier]

Abstract: A lipoxygenase (LOX) cDNA clone (Oep2LOX1) has been isolated from olive fruit (Olea europaea cv. Picual). The deduced amino acid sequence displayed significant similarity to known plant LOX1 sequences. Genomic Southern blot analysis suggests that only one copy of Oep2LOX1 is present in the olive genome. Linolenic acid was the preferred substrate for the recombinant Oep2LOX1, which produced almost exclusively 9-hydroperoxide when linolenic acid was used as substrate, whereas a mixture of 9- and 13-hydroperoxides in a ratio 4:1 was formed from linoleic acid. Expression levels were measured in different tissues of Picual and Arbequina cultivars, including the mesocarp and seed during development and ripening of olive fruit. The results showed that Oep2LOX1 transcript level is spatially and temporally regulated. Besides, the transcriptional regulation of the Oep2LOX1 gene in response to different abiotic stresses was also investigated. Temperature, light and wounding regulate Oep2LOX1 gene expression in olive fruit mesocarp. The physiological role of the Oep2LOX1 gene during olive fruit ripening and in the stress response is discussed. [Copyright &y& Elsevier]

Abstract: Benfotiamine, a lipid-soluble analogue of vitamin B1, is a potent antioxidant that is used as a food supplement for the treatment of diabetic complications. Our recent study (U.C. Yadav et al., Free Radic. Biol. Med. 48:1423–1434, 2010) indicates a novel role for benfotiamine in the prevention of bacterial endotoxin, lipopolysaccharide (LPS)-induced cytotoxicity and inflammatory response in murine macrophages. Nevertheless, it remains unclear how benfotiamine mediates anti-inflammatory effects. In this study, we investigated the anti-inflammatory role of benfotiamine in regulating arachidonic acid (AA) pathway-generated inflammatory lipid mediators in RAW264.7 macrophages. Benfotiamine prevented the LPS-induced activation of cPLA2 and release of AA metabolites such as leukotrienes, prostaglandin E2, thromboxane 2 (TXB2), and prostacyclin (PGI2) in macrophages. Further, LPS-induced expression of AA-metabolizing enzymes such as COX-2, LOX-5, TXB synthase, and PGI2 synthase was significantly blocked by benfotiamine. Furthermore, benfotiamine prevented the LPS-induced phosphorylation of ERK1/2 and expression of transcription factors NF-κB and Egr-1. Benfotiamine also prevented the LPS-induced oxidative stress and protein–HNE adduct formation. Most importantly, compared to specific COX-2 and LOX-5 inhibitors, benfotiamine significantly prevented LPS-induced macrophage death and monocyte adhesion to endothelial cells. Thus, our studies indicate that the dual regulation of the COX and LOX pathways in AA metabolism could be a novel mechanism by which benfotiamine exhibits its potential anti-inflammatory response. [Copyright &y& Elsevier]

Abstract: The anti-inflammatory effect of sulphated polysaccharide (SP) isolated from an algae Padina tetrastromatica was studied. Even though the polysaccharide was found to be a fucan, the composition of this polysaccharide is different from those reported and the mechanism underlying the anti-inflammatory effect also has not been reported so far; perhaps this might be the first report in this regard. Paw edema in rats was induced by injecting 0.1mL, 1% carrageenan suspension in 0.9% NaCl solution into the sub-plantar tissue of the right hind paw. SP was given intraperitoneally (i.p), 1 hour before the injection of carrageenan. Carrageenan caused a significant increase in the activity of inflammatory marker enzymes like lipoxygenases (LOX) and cyclooxygenase (COX) in peripheral blood mononuclear cells (PBMC) and increased the concentration of serum ceruloplasmin and myeloperoxidase (MPO). SP pre-treatment when compared to the reference drug significantly reduced the concentration of COX and LOX in PBMC, ceruloplasmin and MPO in serum and also inhibited the iNOS and COX-2 expression at mRNA level. As this polysaccharide has high anti-inflammatory activity when compared to the anti-inflammatory drug diclofenac, this natural biomolecule could be recommended as a new effective drug for inflammation. [Copyright &y& Elsevier]

Abstract: A new class of 2-pyrrolidinone derivatives was designed, synthesized, and tested for their antioxidant and anti-inflammatory activities. The compounds were evaluated for their inhibitory activity against LOX. The most potent among them, 14d [IC50 0.08 (±0.005)mM], and 14e [IC50 0.0705 (±0.003)mM], were also tested in vivo. The compound 14d induced equipotent inhibition against rat paw edema, which is very close to the effect produced by the commonly used standard, namely indomethacin (47%). The LOX inhibitory activity of the compound 14e proceeds in parallel to the % inhibitory value of lipid peroxidation meaning that this LOX inhibitory activity is supported by the lipid peroxidation inhibition. The molecular features that govern their bioactivity were explored through in silico docking experiments. The results showed that acidic moieties must be placed in certain distance and orientation in the active site of LOX enzyme in order to productively exhibit inhibitory activity. In addition, the 2-pyrrolidinone template significantly contributes in the inhibitory properties of the new compounds. [Copyright &y& Elsevier]

Abstract: Lysyl oxidases (LOXs) are enzymes that permit the covalent crosslinking of the component chains of collagen and elastin. These enzymes are present inside the nuclei of certain mammalian cells. Previous studies have proposed LOX binding to histone H1 in vitro, and histone H1 is known to control global chromatin compaction and mitotic chromosome architecture. Therefore, in the present study, we analyzed chromatin supraorganizational changes, mitotic abnormalities, mitotic indices and cell death ratios in COS-7 and NRK-49F cells with high and low lox expression levels, respectively. The objective was to support biochemical data of LOX–H1 interaction, by providing evidence of chromatin remodeling in vivo, under different lox expressions. Chromatin decondensation assessed by image analysis was observed in COS-7 cells with increased lox expression. This decondensation is suggested to be promoted by LOX actions on histone H1, which loosens the DNA–H1 complex. In NRK-49F cells transfected with antisense lox or subjected to treatment with beta-aminopropionitrile (BAPN), chromatin condensation and nuclear phenotypic variability were found, which may be due to reduced LOX–H1 interaction. When lox expression was increased in COS-7 cells, the frequency of irregular chromosome plates was not affected, but cell proliferation decreased and “cell death preceded by multinucleation” increased. In NRK-49F cells there was accelerated proliferation induced by transfection with the antisense lox, and confirmed when cells were treated with BAPN. Apoptosis increased in NRK-49F cells only with BAPN treatment whereas cell death preceded by multinucleation increased only after antisense lox transfection. The data presented herein regarding chromatin remodeling indirectly support the hypothesis that LOX binds to histone H1 in vivo. Cell proliferation in COS-7 and NRK-49F cells and cell death at least in COS-7 cells agree with predicted effects of LOX interference in these processes. [Copyright &y& Elsevier]

Abstract: A series of novel acrylic acid derivatives bearing at the 3 position thienyl, furfuryl and 3,5-ditert-butyl-4-hydroxyphenyl substituents have been designed, synthesized and tested as potential dual lipoxygenase/cyclooxygenase-1 (LOX/COX-1) inhibitors and as antioxidant and anti-inflammatory agents. Some compounds have shown moderate antioxidant and COX-1 inhibitory activities, very good anti-inflammatory activity and an inhibition of soybean lipoxygenase (LOX) higher than caffeic acid. In particular, compound 4I disclosed a moderate in vitro LOX inhibition with an IC50 = 100 μM whereas compounds 1I and 2II exhibited the best, albeit poor, activity as COX-1 inhibition (75% inhibition at 100 μM). Good radical scavenging properties were shown by compounds 4I, 3I and 1II. Docking simulations performed on LOX inhibitor 4I and COX-1 inhibitor 1I indicated that hydrophobic key interactions may govern the enzyme-inhibitor binding. [Copyright &y& Elsevier]

Abstract: Head and neck cancers are known to synthesize arachidonic acid metabolites. Interfering with arachidonic acid metabolism may inhibit growth and invasiveness of cancer cells. In this study we investigate effects of sulindac (the non-selective COX inhibitor), aspirin (the irreversible, preferential COX-1 inhibitor), NS-398 (the selective COX-2 inhibitor), NDGA (nordihydroguaiaretic acid, the selective LOX inhibitor) and ETYA (5,8,11,14-eicosatetraynoic acid, the COX and LOX inhibitor) on cell viability, MMP-2 and MMP-9 activities, and in vitro invasion of cancer cells derived from primary and metastatic head and neck, and colon cancers. The inhibitors of COX and/or LOX could inhibit cell proliferation, MMP activity and invasion in head and neck and colon cancer cells. However, the inhibitory effect was obviously observed in colon cancer cells. Inhibition of arachidonic acid metabolism caused a decrease in cancer cell motility, which partially explained by the inhibition of MMPs. Therefore, COX and LOX pathways play important roles in head and neck cancer cell growth. [ABSTRACT FROM AUTHOR]

Abstract: Entomosporium leaf and berry spot represent the most important disease of saskatoons (Amelanchier alnifolia Nutt.). This disease, caused by the ascomycete Entomosporium mespili (D.C.) Sacc., is difficult to control via conventional methods and no known saskatoon cultivar carries resistance to this pathogen. The aim of the present study was to enhance existing and induced defense responses of saskatoons using two host defense inducers, namely jasmonic acid and an extract from Canada milkvetch on two saskatoon cultivars, Smoky and Martin. Both inducers exhibited an ability to differentially induce the synthesis/accumulation of defense-related genes including those encoding for PR-1, PR-2, PR-5, LOX and PAL. Pre-treatment of saskatoon leaves with these inducers reduced the disease levels especially when applied to the moderately susceptible cultivar Martin. An accumulation of various hydroxycinnamic acid and proanthocyanidin derivatives also correlated with the disease levels recorded on both cultivars. Results are discussed on the basis of the induced pathways in an attempt to lay the ground for a better understanding of this host–pathogen interaction. In the meantime, we have shown that the use of defense enhancers may be useful in integrated management strategies to control entomosporium leaf and berry spot in saskatoons. [Copyright &y& Elsevier]

Abstract: An association between dietary fatty, obesity and an increased risk of developing breast cancer has been suggested. In breast cancer cells, free fatty acids (FFAs) mediate biological effects including cell proliferation and ERK1/2 activation. However, the contribution of FFAs to tumor progression and metastasis through the regulation of cell migration has not been studied. We demonstrated here that stimulation on MDA-MB-231 breast cancer cells with oleic acid (OA) promotes an increase in focal adhesion kinase (FAK) phosphorylation, as revealed by site-specific antibodies that recognize the phosphorylation state of FAK at tyrosine-397 (Tyr-397), Tyr-577 and in vitro kinase assays. OA also promotes the migration of MDA-MB-231 cells. Treatment with Gi/Go proteins, phospholipase C (PLC), lipoxygenases (LOXs) and Src inhibitor prevents FAK phosphorylation and cell migration. In summary, our findings delineate a new signal transduction pathway, where OA mediates the production of arachidonic acid (AA), and then AA metabolites mediate FAK phosphorylation and cell migration in MDA-MB-231 breast cancer cells. [Copyright &y& Elsevier]

Abstract: In order to help explain the absence of the brown kelp Lessonia nigrescens from a coastal environment chronically enriched with copper, we characterized the biochemical responses induced by copper stress in this kelp and compared them with those displayed by the copper tolerant brown alga Scytosiphon lomentaria. These algae were cultivated with increasing concentrations of copper (20, 40 and 100μgL−1) for 96h and the temporal production of hydrogen peroxide, superoxide anions and lipoperoxides as well as the activities of antioxidant enzymes catalase (CAT), glutathione peroxidase (GP), ascorbate peroxidase (AP), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) and the activity of the defense enzyme lipoxygenase (LOX) were determined. In L. nigrescens and S. lomentaria, a single peak of hydrogen peroxide was detected, with similar maxima after 3h of copper exposure, although in L. nigrescens buffering took longer. Superoxide anions, on the other hand, were only detected in L. nigrescens. The production of lipoperoxides in L. nigrescens increased steadily at higher copper levels, in a pattern clearly different to their rapid stabilization in S. lomentaria. We suggest that the accumulation of lipoperoxides might be related to LOX, whose activity also increases with exposure time. Furthermore, activities of the antioxidant enzymes CAT, GP, AP and DHAR were lower in L. nigrescens than in S. lomentaria, and GP and DHAR were completely inhibited at higher copper concentrations. Since these enzymes also detoxify fatty acid hydroperoxides, their inhibition, together with the activation of LOX, may explain the persistent and copper-dependent levels of lipoperoxides in L. nigrescens. Based on terrestrial plant models demonstrating toxic effects of lipoperoxides, and on our results on organellar ultrastructural changes, we suggest that copper toxicity induced an uncontrolled lipoperoxide accumulation which may lead to cell damage and dysfunction in L. nigrescens, explaining at least partially, the absence of this kelp in a copper-enriched coastal environment. [Copyright &y& Elsevier]

Abstract: Background: Classical lysyl oxidase (LO) is involved in the stabilization and repair of extracellular matrix by the oxidization of lysine residues in collagen and elastin. Five genetically distinct species of LOs (LOX and LOXL1–4) have been identified, but their functions remain unclear. Objectives: To investigate the regulation of LOs during differentiation and cell adhesion of cultured keratinocytes. Methods: LO mRNA and polypeptides levels in the suspension and adhesive cultures were measured using real-time PCR, immunoblot and immunofluorescence assays. Localization of LOX, LOXL1 and LOXL2 gene transcripts in normal epidermis was assessed by in situ hybridization. Results: In the epidermis and cultured keratinocytes, LOX, LOXL1 and LOXL2 mRNA levels were predominant, and LOXL3 and LOXL4 were minor components. When cultured keratinocytes were induced to terminal differentiation, LOX expression increased 12-fold and LOXL2 expression decreased 0.1-fold, while LOXL1 mRNA level was essentially unchanged. When growth-arrested cells were allowed to adhere to extracellular matrices, LOXL2 mRNA level was stimulated 7-fold by fibronectin or type IV collagen substrate, whereas LOX mRNA level was decreased 0.1-fold by all substrates tested. Reciprocal regulation of LOX and LOXL2 expression during differentiation and adhesion was confirmed by immunoblot analysis and double immunofluorescent observation of cultured cells using anti-LOX and anti-LOXL2 antibodies. In situ hybridization analysis of normal epidermis revealed LOXL2 mRNA mainly in the lower epidermis, LOX mRNA in the upper layer of epidermis and LOXL1 throughout the epidermis. Conclusion: LOX expression in cultured keratinocytes is related to keratinization whereas LOXL2 expression is related to cell–matrix interaction. [Copyright &y& Elsevier]

[Display omitted] Inflammatory pain serves as a protective defense mechanism which becomes pathological when it turns into chronic inflammatory pain. This transition is mediated by a variety of peripheral mediators that sensitize nociceptors and increase pain perception in sensory neurons. Besides cytokines, chemokines and growth factors, accumulating evidence shows that oxidized lipids, such as eicosanoids and oxidized linoleic acid metabolites, contribute to this sensitization process. Most notably, the oxidized linoleic acid metabolite and partial TRPV1 agonist 9-HODE (hydroxyoctadecadienoic acid) was shown to be involved in this sensitization process. However, it is still unknown how some of the oxidized linoleic acid metabolites are synthesized in the inflammatory environment and in which phase of inflammation they become relevant. Here we show that the concentrations of oxidized linoleic acid metabolites, especially 9-HODE and 13-HODE, are significantly increased in inflamed paw tissue and the corresponding dorsal root ganglia in the sub-chronic phase of inflammation. Surprisingly, classical inflammatory lipid markers, such as prostaglandins were at basal levels in this phase of inflammation. Moreover, we revealed the cell type specific synthesis pathways of oxidized linoleic acid metabolites in primary macrophages, primary neutrophils and dorsal root ganglia. Finally, we show that blocking the most elevated metabolites 9-HODE and 13-HODE at the site of inflammation in the sub-chronic phase of inflammation, leads to a significant relief of mechanical and thermal hypersensitivity in vivo. In summary, these data offer an approach to specifically target oxidized linoleic acid metabolites in the transition of acute inflammatory pain to chronic inflammatory pain. [ABSTRACT FROM AUTHOR]

Abstract: A series of adamantane derivatives of thiazolyl-N-substituted amides were synthesized in a three-step reaction and tested for anti-inflammatory activity as well as lipoxygenase and cycloxygenase inhibitory actions. Theoretical calculation of their lipophilicity, as C log P was performed. The effect of the synthesized compounds on inflammation, using the carrageenin-induced mouse paw oedema model was studied and compared to indomethacin. In general, the studied compounds were found to be potent anti-inflammatory agents (29.6–81.5%). Anti-inflammatory activity was influenced by some structural characteristics of the synthesized compounds. The lipoxygenase inhibitory activity was tested by the conversion of sodium linoleate to 13-hydroperoxylinoleic acid. Low inhibitory activity was observed. Evaluation of COX-1 and COX-2 inhibitory activities of the compounds revealed a COX-1 inhibitory potential, comparable to that of naproxen for some of the compounds and a low to moderate COX-2 inhibitory potential. Comparison of the in vivo and in vitro results leads to the conclusion that most compounds of this series may be involved in other mechanisms of inflammation, too. [Copyright &y& Elsevier]

Abstract: Duchenne muscular dystrophy (DMD; dystrophin-deficiency) causes dilated cardiomyopathy in the second decade of life in affected males. We studied the dystrophin-deficient mouse heart (mdx) using high-frequency echocardiography, histomorphometry, and gene expression profiling. Heart dysfunction was prominent at 9–10months of age and showed significantly increased LV internal diameter (end systole) and decreased posterior wall thickness. This cardiomyopathy was associated with a 30% decrease in shortening fraction. Histologically, there was a 10-fold increase in connective tissue volume (fibrosis). mRNA profiling with RT-PCR validation showed activation of key pro-fibrotic genes, including Nox4 and Lox. The Nox gene family expression differed in mdx heart and skeletal muscle, where Nox2 was specifically induced in skeletal muscle while Nox4 was specifically induced in heart. This is the first report of an altered profibrotic gene expression profile in cardiac tissue of dystrophic mice showing echocardiographic evidence of cardiomyopathy. [Copyright &y& Elsevier]

Abstract: A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, synthesized, and screened in vitro for anti-inflammatory activity. These compounds were designed for evaluation as dual inhibitors of cyclooxygenases (COX-1 and COX-2) and lipoxygenases (LOX-5, LOX-12, and LOX-15) that are responsible for inflammation and pain. All pyrazoline molecules prepared are optically active and compounds that are more potent in COX-2 inhibitory activity (5a and 5f) were resolved by chiral column and each enantiomer was tested for cyclooxygenase inhibitory activity. Molecular modeling and comparison of molecular models of 5a enantiomers with that of celecoxib model shows that 5a (enantiomer-1) and 5a (enantiomer-2) have more hydrogen bonding interactions in the catalytic domain of COX-2 enzyme than celecoxib. Compounds 5a, 5e, and 5f showed moderate to good LOX-5 and LOX-15 inhibitory activity and this is comparable to that of celecoxib and more potent than rofecoxib. [Copyright &y& Elsevier]

Abstract: Background: Genes such as carbonic anhydrase IX (Ca9), glucose transporter 1 (Glut1), lactate dehydrogenase A (LDH-A), osteopontin (OPN) and lysyl oxidase (LOX) have been suggested as hypoxic markers, but inconsistent results suggest that factors other than oxygen influence their expression. The current study is a detailed investigation using a range of pH values from 6.3 to 7.5 in two human cell lines to establish the pH dependency of hypoxia induced gene expression. Methods: Human tumour cell lines (uterine cervix squamous cell carcinoma (SiHa) and pharyngeal squamous cell carcinoma [FaDuDD]) were used. Hypoxia was induced by gassing cells in airtight chambers with various oxygen concentrations (21%, 1%, 0.1%, 0.01% and 0%) for up to 24h. The media were titrated to a range of pH values (7.5, 7.0, 6.7, 6.5 and 6.3). Gene expression was determined by real-time PCR. Results: In both SiHa and FaDuDD cells Ca9 and LOX reached the highest level of expression at 1% oxygen. In FaDuDD cells, a pH of 6.5 had a medium suppression effect on the hypoxia induced expression of Ca9. pH 6.3 resulted in severe suppression of expression for Ca9 and LOX in both SiHa and FaDuDD. Glut1 and LDH-A had a similar expression pattern to each other, with a maximum expression at 0.01% oxygen, in both cell lines. For these genes pH 6.5 and 6.3 changed the expression pattern in SiHa cells. OPN was up regulated at low oxygen in SiHa cells, but was not induced by hypoxia in FaDuDD cells. Conclusion: As tumour hypoxia occurs in a deprived microenvironment, other environmental factors, for example low pH, might interact with the effect of low oxygen concentration on gene expression. This study shows that pH in two cell lines has a profound influence on the oxygen dependent induction of certain endogenous hypoxic markers. [Copyright &y& Elsevier]

Abstract: Although inflammation has long been known as a localized protective reaction of tissue to irritation, injury, or infection, characterized by pain, redness, swelling, and sometimes loss of function, there has been a new realization about its role in a wide variety of diseases, including cancer. While acute inflammation is a part of the defense response, chronic inflammation can lead to cancer, diabetes, cardiovascular, pulmonary, and neurological diseases. Several pro-inflammatory gene products have been identified that mediate a critical role in suppression of apoptosis, proliferation, angiogenesis, invasion, and metastasis. Among these gene products are TNF and members of its superfamily, IL-1α, IL-1β, IL-6, IL-8, IL-18, chemokines, MMP-9, VEGF, COX-2, and 5-LOX. The expression of all these genes are mainly regulated by the transcription factor NF-κB, which is constitutively active in most tumors and is induced by carcinogens (such as cigarette smoke), tumor promoters, carcinogenic viral proteins (HIV-tat, HIV-nef, HIV-vpr, KHSV, EBV-LMP1, HTLV1-tax, HPV, HCV, and HBV), chemotherapeutic agents, and γ-irradiation. These observations imply that anti-inflammatory agents that suppress NF-κB or NF-κB-regulated products should have a potential in both the prevention and treatment of cancer. The current review describes in detail the critical link between inflammation and cancer. [Copyright &y& Elsevier]

Abstract: The melanogenic marine bacterium M. mediterranea synthesizes marinocine, a protein with antibacterial activity. We cloned the gene coding for this protein and named it lodA [P. Lucas–Elío, P. Hernández, A. Sanchez-Amat, F. Solano, Purification and partial characterization of marinocine, a new broad-spectrum antibacterial protein produced by Marinomonas mediterranea. Biochim. Biophys. Acta 1721 (2005) 193–203; P. Lucas-Elío, D. Gómez, F. Solano, A. Sanchez-Amat, The antimicrobial activity of marinocine, synthesized by M. mediterranea, is due to the hydrogen peroxide generated by its lysine oxidase activity. J. Bacteriol. 188 (2006) 2493–2501]. Now, we show that this protein is a new type of lysine oxidase which catalyzes the oxidative deamination of free l-lysine into 6-semialdehyde 2-aminoadipic acid, ammonia and hydrogen peroxide. This new enzyme is compared to other enzymes related to lysine transformation. Two different groups have been used for comparison. Enzymes in the first group lead to 2-aminoadipic acid as a final product. The second one would be enzymes catalyzing the oxidative deamination of lysine releasing H2O2, namely lysine-α-oxidase (LαO) and lysyl oxidase (Lox). Kinetic properties, substrate specificity and inhibition pattern show clear differences with all above mentioned lysine-related enzymes. Thus, we propose to rename this enzyme lysine-ε-oxidase (lod for the gene) instead of marinocine. Lod shows high stereospecificity for free l-lysine, it is inhibited by substrate analogues, such as cadaverine and 6-aminocaproic acid, and also by β-aminopropionitrile, suggesting the existence of a tyrosine-derived quinone cofactor at its active site. [Copyright &y& Elsevier]

Abstract: The release of soluble amyloid precursor protein α (sAPPα), produced during α-secretase processing by cleavage within the β amyloid peptide domain of APP, is highly regulated by several external and internal signals. Because evidence suggests the involvement of inflammatory processes in the pathology of Alzheimer''s disease and APP formation, we examined the involvement of the phospholipase A2 (PLA2) pathway and of its downstream cyclooxygenase (COX) and lipoxygenase (LOX) pathways in the regulation of sAPPα, release induced by muscarinic receptor activation in SH-SY5Y cells. The amount of sAPP released into the culture medium was analyzed using a monoclonal 6E10 antibody detecting sAPPα. Treatment with the PLA2 inhibitor, manoalide, blocked the release of oxoM (muscarinic receptor agonist)-stimulated sAPPα, and the muscarinic receptor-mediated sAPPα release was increased by the non-selective PLA2 activator mellitin. COX and LOX inhibitors inhibited exogenous AA-induced sAPPα release, but upregulated basal constitutive sAPPα release. However, treatment with COX or LOX inhibitors failed to significantly change oxoM-stimulated sAPPα release, and furthermore, muscarinic receptor activation inhibited AA-stimulated COX activity. Our results suggest that sAPPα release induced by muscarinic receptor activation is regulated by AA generation via PLA2 activation independently of COX and LOX activities, but that the COX and LOX pathways are possibly involved in the constitutive release of sAPPα. [Copyright &y& Elsevier]

Abstract: Non-steroidal anti-inflammatory drugs (NSAIDs) are used primarily for the treatment of inflammatory diseases. However, certain NSAIDs also have a chemopreventive effect on the development of human colorectal and other cancers. NSAIDs inhibit cyclooxygenase-1 (COX-1) and/or cyclooxygenase-2 (COX-2) activity and considerable evidence supports a role for prostaglandins in cancer development. However, the chemopreventive effect of NSAIDs on colorectal and other cancers appears also to be partially independent of COX activity. COX inhibitors also alter the expression of a number of genes that influence cancer development. One such gene is NAG-1 (NSAID-Activated Gene), a critical gene regulated by a number of COX inhibitors and chemopreventive chemicals. Therefore, this article will discuss the evidence supporting the conclusion that the chemo-preventive activity of COX inhibitors is mediated, in part, by altered gene expression with an emphasis on NAG-1 studies. This review may also provide new insights into how chemicals and environmental factors influence cancer development. In view of the cardiovascular and gastrointestinal toxic side effects of COX-2 inhibitors and non-selective COX inhibitors, respectively, the results presented here may provide the basis for the development of a new family of anti-tumorigenic compounds acting independent of COX inhibition. [Copyright &y& Elsevier]

Lysyl oxidase (Lox) is a copper-dependent amine oxidase that catalyzes the cross-linking of collagen and elastin fibers in the extracellular matrix (ECM). In mammals, four closely related Lox-like enzymes have been described that share a highly conserved catalytic domain with Lox. We have characterized Xenopus laevis cDNAs for Lox, Loxl-1, and Loxl-3, and show that they are expressed during early embryonic development. Using RT-PCR we detected maternal transcripts for Xloxl-1, but levels remained low until tailbud stages. Transcripts for Xlox and Xloxl-3 were not detected until early neurulae, although transcripts for Xlox remained at low levels until tailbud stages. Whole mount in situ hybridization showed that transcripts for Xloxl-1 and Xloxl-3 are localized in the notochord, while transcripts for Xlox are found in the notochord, somites, and head. X. laevis Lox-like enzymes were inhibited by incubating embryos, from cleavage stages to tadpole stages, in β-aminopropionitrile, a specific inhibitor of the catalytic domain. The resulting embryos appeared to differentiate normally but suffered from poor collagen fiber formation. Defects included kinks in the notochord, a posterior shift of the somites, abnormal gut coiling, and the formation of edemas. Our data suggest that Lox-related enzymes are required for the proper formation of the ECM during X. laevis development. [ABSTRACT FROM AUTHOR]

Abstract: Different peroxidases were used to catalyze the synthesis of neolignan. Horseradish peroxidase (type I, Sigma) was employed successfully to catalyze the formation of magnolol by the phenolic oxidative coupling of allyphenol. The effects of organic co-solvents, pH, addition rate of H2O2, and the ratio of enzyme/substrate on the yields of dimer were studied. After the peroxidase-catalyzed reaction was performed, different neolignans were isolated and identified as magnolol (3), the trimeric ortho–ortho-coupled product dunnianol (4), the ortho-O-coupled product isomagnolol (5), and the Pummerer''s ketone derivative (6). The inhibitory activities of magnolol against cyclo-oxygenase and lipoxygenase were also reported. [Copyright &y& Elsevier]

Occurrence of an essential enzyme in jasmonate (JA) biosynthesis, the allene oxide cyclase, (AOC) was analyzed in different developmental stages and various organs of Arabidopsis thaliana plants by immuno blot analysis and immunocytological approaches. Levels of AOC and of the two preceding enzymes in JA biosynthesis increased during seedling development accompanied by increased levels of JA and 12-oxophytodienoic acid levels after 4 and 8 weeks. Most tissues including all vascular bundles and that of flower buds contain AOC protein. Flowers shortly before opening, however, contain AOC protein preferentially in ovules, stigma cells and vascular bundles, whereas in anthers and pollen AOC could not be detected. The putative roles of AOC and JA in development are discussed. [Copyright &y& Elsevier]

First results obtained during the investigation of the transient ignition process in a cryogenic model rocket combustion chamber are reported. Ignition of the propellants LOX and GH2 has been initiated with a pulsed laser and ignition and flame stabilization processes have been analyzed using high-speed visualization methods. Local flame velocities as well as local convection velocities at the point of ignition are determined by image displacement velocimetry methods. Depending on the injection conditions of the propellants, some distinct phases of the transient start-up process could be observed and are discussed in terms of Weber and Reynolds number. [Copyright &y& Elsevier]