Search results for "Arachidonate 5-Lipoxygenase"
showing 10 items of 43 documents
Synthesis and evaluation of 2-tosylamino and 2-tosyliminopyrimidine derivatives as inhibitors of some leukocyte functions
2003
Abstract We have studied the potential anti-inflammatory effects of 20 2-tosylamino and 2-tosyliminopyrimidine new derivatives in human neutrophils. We have evaluated their interference with some leukocyte functions and 5-lipoxygenase activity. All the compounds reduced neutrophil degranulation process at concentrations in the μM range. Besides, compounds with a phenolic substitution inhibited leukotriene B 4 biosynthesis in neutrophils and decreased the cell-free 5-lipoxygenase activity. This study demonstrates that 2-tosylamino and 2-tosyliminopyrimidine derivatives can reduce the activation of neutrophil cells which may have relevance for the modulation of the inflammatory response.
Arachidonate 5-lipoxygenase (ALOX5) gene polymorphism is associated with Alzheimer's disease and body mass index
2016
IF 2.126; International audience; Dementias of old age, in particular Alzheimer's disease (AD), pose a growing threat to the longevity and quality of life of individuals as well as whole societies world-wide. The risk factors are both genetic and environmental (lifestyle) and there is an overlap with similar factors predisposing to cardiovascular diseases (CVD). Using a case control genetic approach, we have identified a SNP (rs10507391) in ALOX5 gene, previously associated with an increased risk of stroke, as a novel genetic risk factor for AD. ALOX5 gene encodes a 5'-lipoxygenase (5'-LO) activating protein (FLAP), a crucial component of the arachidonic acid/leukotriene inflammatory cascad…
Role of cyclooxygenae-2 and 5-lypoxygenase polymorphisms in Alzheimer's disease in a population from northern Italy:implications for pharmacogenomics
2010
Alzheimer's disease (AD) is a neurodegenerative disorder clinically characterized by cognitive deficit with progressive worsening of memory. Recent data indicate that neurons, as well as other brain cells, can express enzymes such as cyclooxygenases (COXs) and 5-lipoxygenase (5-LO) which are considered important in inflammatory cells. Moreover, it has been demonstrated that COX-2 and 5-LO enzymes play a considerable role in the pathophysiology of AD. In order to assess the possible role of COX-2 and 5-LO single nucleotide polymorphisms (SNPs) in AD, we examined their distribution in 341 AD patients and 190 controls from Northern Italy. A significant difference was observed in the distributi…
Suppression of leukotriene B4 and tumour necrosis factor alpha release in acute inflammatory responses by novel prenylated hydroquinone derivatives.
1998
A series of prenyl hydroquinone derivatives synthesized as structural analogs of marine products were tested for their effects on inflammatory responses in vitro and in vivo. 2-Prenyl-1,4-hydroquinone (H1), 2-diprenyl-1,4-hydroquinone (H2), 2-triprenyl-1,4-hydroquinone (H3) and 2-tetraprenyl-1,4-hydroquinone (H4) scavenged reactive oxygen species and inhibited 5-lipoxygenase (5-LO) activity in human neutrophils. The inhibition of 5-LO activity was demonstrated in vivo in the mouse air pouch injected with zymosan and arachidonic acid-induced ear inflammation. The four compounds suppressed the production of tumour necrosis factor alpha (TNFalpha) in J774 cells stimulated with lipopolysacchari…
Decreased Paraoxonase-2 Expression in Human Carotids During the Progression of Atherosclerosis
2008
Objective— Many gene products involved in oxidation and inflammation are implicated in the pathogenesis of atherosclerosis. We investigated paraoxonase 2 (PON2), 5-lipoxygenase (5-LO), and 5-LO activating protein (FLAP) expression and malondialdehyde (MDA) levels in carotid lesions to assess their involvement in plaque formation. Methods and Results— We measured gene expression and MDA levels in atherosclerotic plaques from 59 patients undergoing carotid endarterectomy, and in plaque-adjacent tissue from 41/59 patients. Twenty-three fetal carotids and 6 mammary arteries were also investigated. Real-time polymerase chain reaction and immunohistochemistry revealed decreased PON2 expression i…
Antiasthmatic effects of onions: Inhibition of 5-lipoxygenase and cyclooxygenase in vitro by thiosulfinates and “Cepaenes”
1990
Nine thiosulfinates (TS) and four "Cepaenes" (CS) isolated from onions and/or synthetized by us showed dose dependent (0.25 to 100 microM) marked inhibitory effects on both cyclooxygenase (CA, tested on sheep seminal vesicle microsomes) and 5-lipoxygenase activity (LO, tested on porcine leukocytes). The following rank order of activity was observed: saturated aliphatic TS less than aromatic TS approximately alpha, beta-unsaturated TS less than CS. CS inhibited both CA and LO by more than 75% at 10 and 1 microM concentrations respectively. Most likely, these in vitro effects are responsible for antiinflammatory and antiasthmatic properties of onion extracts observed in vivo, at least in part.
Inhibition of human sPLA2 and 5-lipoxygenase activities by two neo-clerodane diterpenoids
1999
Abstract The inhibitory effect of two neo -clerodane diterpenoids, E -isolinaridial (EI) and its methylketone derivative (EIM), isolated from Linaria saxatilis var. glutinosa , on PLA2 and other enzyme activities involved in the inflammatory process was studied. Both compounds inhibited human synovial sPLA 2 in a concentration-dependent manner with IC 50 values of 0.20 and 0.49 μM, respectively, similar to scalaradial. Besides, these compounds decreased the cell-free 5-lipoxygenase activity and A23187-induced neutrophil LTB 4 biosynthesis. Another function of human neutrophils, such as receptor-mediated degranulation, was also significantly reduced. In contrast, none of the compounds affect…
Diaryl-dithiolanes and -isothiazoles: COX-1/COX-2 and 5-LOX-inhibitory, OH scavenging and anti-adhesive activities
2008
Three series of non-steroidal anti-inflammatory drugs (NSAIDs) inhibiting the cyclooxygenase/5-lipoxygenase (COX/5-LOX) pathways as such as formation of hydroxyl radicals and adhesion were prepared: 4,5-diaryl isothiazoles, 4,5-diaryl 3H-1,2-dithiole-3-thiones and 4,5-diaryl 3H-1,2-dithiole-3-ones. The aim of the present study was to develop substances which can intervene into the inflammatory processes via different mechanisms of action as multiple target non-steroidal anti-inflammatory drugs (MTNSAIDs) with increased anti-inflammatory potential. The current lead 11a was evaluated in COX-1/2, 5-LOX and (*)OH scavenging in vitro assays and in a static adhesion assay where it proved to inhib…
Screening of some rare endemic Italian plants for inhibitory activity on 5-lipoxygenase
2003
Abstract The extracts of four rare plants found on the islands of Sicily, Vulcano and Marettimo, Southern Italy, were screened for their inhibitory effect on the production of leukotriene B 4 by 5-lipoxygenase in intact cells. The methanol extracts of pods of Cytisus aeolicus and aerial parts of Thymus richardii were the most active extracts, inhibiting almost completely the leukotriene B 4 production at 200 and 50 μg/ml, respectively.
Inhibition of 5-lipoxygenase activity by the natural anti-inflammatory compound aethiopinone
2001
Objetive and Design: We have investigated the mechanisms of action of aethiopinone, an anti-inflammatory compound from Salvia aethiopis L. roots.¶Material and Subjects: Human neutrophils from healthy volunteers and murine peritoneal macrophages. Swiss mice were randomly divided into groups of six animals.¶Treatment: Test compounds were applied topically in the mouse ear oedema test. In the air pouch, mice received aethiopinone (0.001-0.5 μmol/pouch or 12.5-50 mg/kg p.o.).¶Methods: LTB4 production was assayed in human neutrophils and COX-2 and iNOS activities in murine macrophages. Air pouches were induced subcutaneously in mice and injected with zymosan on the day six. Mouse ear oedema was …