Selective inhibitors of secretory phospholipase A2 and lipoprotein-associated phospholipase A2 are potential candidates for reducing recurrent cardiovascular events in patients with established coronary heart disease (CHD). With the active enrollment of CHD patients into phase III clinical trials with both classes of inhibitors, this article reviews the available experimental animal and human trial evidence that provides the rationale for the development of the phospholipase A2 inhibitors varespladib methyl and darapladib as preventive therapy. RECENT FINDINGS: Recently completed experimental animal studies, human biomarker data, and vascular imaging studies provide support for proceeding with clinical outcome trials secretory phospholipase A2 and lipoprotein-associated phospholipase A2 inhibition. SUMMARY: Both secretory phospholipase A2 and lipoprotein-associated phospholipase A2 inhibitors hold promise for the reduction of recurrent cardiovascular events in patients treated with current standards of care. The completion of the ongoing clinical event trials has the potential to provide a new dimension to secondary preventive therapy.

• MeSH
• 1-alkyl-2-acetylglycerofosfocholinesterasa antagonisté a inhibitory   MeSH
• acetáty aplikace a dávkování   terapeutické užití   MeSH
• ateroskleróza enzymologie   epidemiologie   farmakoterapie   patofyziologie   MeSH
• benzaldehydy aplikace a dávkování   terapeutické užití   MeSH
• biologické markery analýza   MeSH
• cílená molekulární terapie metody   MeSH
• indoly aplikace a dávkování   terapeutické užití   MeSH
• klinické zkoušky kontrolované jako téma MeSH
• lékové formy MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• myši transgenní MeSH
• myši MeSH
• oximy aplikace a dávkování   terapeutické užití   MeSH
• rizikové faktory MeSH
• sekreční fosfolipasy A2 antagonisté a inhibitory   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• přehledy MeSH

The inflammatory process is a natural self-defense response of the organism to damage agents and its action mechanism involves a series of complex reactions. However, in some cases, this process can become chronic, causing much harm to the body. Therefore, over the years, many anti-inflammatory drugs have been developed aiming to decrease the concentrations of inflammatory mediators in the organism, which is a way of controlling these abnormal chain reactions. The main target of conventional anti-inflammatory drugs is the cyclooxygenase (COX) enzyme, but its use implies several side effects. Thus, based on these limitations, many studies have been performed, aiming to create new drugs, with new action mechanisms. In this sense, the phospholipase A2 (PLA2) enzymes stand out. Among all the existing isoforms, secretory PLA2 is the major target for inhibitor development, since many studies have proven that this enzyme participates in various inflammatory conditions, such as cancer, Alzheimer and arthritis. Finally, for the purpose of developing anti-inflammatory drugs that are sPLA2 inhibitors, many molecules have been designed. Accordingly, this work presents an overview of inflammatory processes and mediators, the current available anti-inflammatory drugs, and it briefly covers the PLA2 enzymes, as well as the diverse structural array of the newest sPLA2 inhibitors as a possible target for the production of new anti-inflammatory drugs.

• MeSH
• antiflogistika farmakologie   MeSH
• cyklooxygenasa 2 MeSH
• fosfolipasy A2 MeSH
• inhibitory enzymů MeSH
• inhibitory fosfolipasy A2 MeSH
• lidé MeSH
• nádory MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Human phospholipase A₂ (hPLA₂) of the IIA group (HGIIA) catalyzes the hydrolysis of membrane phospholipids, producing arachidonic acid and originating potent inflammatory mediators. Therefore, molecules that can inhibit this enzyme are a source of potential anti-inflammatory drugs, with different action mechanisms of known anti-inflammatory agents. For the study and development of new anti-inflammatory drugs with this action mechanism, snake venom PLA₂ (svPLA₂) can be employed, since the svPLA₂ has high similarity with the human PLA₂ HGIIA. Despite the high similarity between these secretory PLA₂s, it is still not clear if these toxins can really be employed as an experimental model to predict the interactions that occur with the human PLA₂ HGIIA and its inhibitors. Thus, the present study aims to compare and evaluate, by means of theoretical calculations, docking and molecular dynamics simulations, as well as experimental studies, the interactions of human PLA₂ HGIIA and two svPLA₂s,Bothrops toxin II and Crotoxin B (BthTX-II and CB, respectively). Our theoretical findings corroborate experimental data and point out that the human PLA₂ HGIIA and svPLA₂ BthTX-II lead to similar interactions with the studied compounds. From our results, the svPLA₂ BthTX-II can be used as an experimental model for the development of anti-inflammatory drugs for therapy in humans.

• MeSH
• antiflogistika chemie   MeSH
• crotoxin metabolismus   MeSH
• fosfolipasy A2, skupina II MeSH
• fosfolipasy A2 chemie   MeSH
• inhibitory fosfolipasy A2 chemie   MeSH
• jedy chřestýšů enzymologie   MeSH
• kyselina vanilová chemie   MeSH
• lidé MeSH
• sekvence aminokyselin MeSH
• simulace molekulového dockingu MeSH
• vodíková vazba MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Adaptation to chronic intermittent hypoxia (CIH) is associated with reactive oxygen species (ROS) generation implicated in the improved cardiac tolerance against acute ischemia-reperfusion injury. Phospholipases A2 (PLA2s) play an important role in cardiomyocyte phospholipid metabolism influencing membrane homeostasis. Here we aimed to determine the effect of CIH (7000 m, 8 h/day, 5 weeks) on the expression of cytosolic PLA2 (cPLA2α), its phosphorylated form (p-cPLA2α), calcium-independent (iPLA2), and secretory (sPLA2IIA) at protein and mRNA levels, as well as fatty acids (FA) profile in left ventricular myocardium of adult male Wistar rats. Chronic administration of antioxidant tempol was used to verify the ROS involvement in CIH effect on PLA2s expression and phospholipid FA remodeling. While CIH did not affect PLA2s mRNA levels, it increased the total cPLA2α protein in cytosol and membranes (by 191% and 38%, respectively) and p-cPLA2α (by 23%) in membranes. On the contrary, both iPLA2 and sPLA2IIA were downregulated by CIH. CIH further decreased phospholipid n-6 polyunsaturated FA (PUFA) and increased n-3 PUFA proportion. Tempol treatment prevented only CIH-induced cPLA2α up-regulation and its phosphorylation on Ser505. Our results show that CIH diversely affect myocardial PLA2s and suggest that ROS are responsible for the activation of cPLA2α under these conditions.

• MeSH
• antioxidancia farmakologie   MeSH
• chronická nemoc MeSH
• cyklické N-oxidy farmakologie   MeSH
• fosfolipasy A2, skupina IV genetika   metabolismus   MeSH
• fosforylace účinky léků   MeSH
• hypoxie enzymologie   metabolismus   MeSH
• krysa rodu rattus MeSH
• mastné kyseliny metabolismus   MeSH
• potkani Wistar MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• regulace genové exprese enzymů účinky léků   MeSH
• spinové značení MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

AIMS: Pancreatic β-cell chronic lipotoxicity evolves from acute free fatty acid (FA)-mediated oxidative stress, unprotected by antioxidant mechanisms. Since mitochondrial uncoupling protein-2 (UCP2) plays antioxidant and insulin-regulating roles in pancreatic β-cells, we tested our hypothesis, that UCP2-mediated uncoupling attenuating mitochondrial superoxide production is initiated by FA release due to a direct H2O2-induced activation of mitochondrial phospholipase iPLA2γ. RESULTS: Pro-oxidant tert-butylhydroperoxide increased respiration, decreased membrane potential and mitochondrial matrix superoxide release rates of control but not UCP2- or iPLA2γ-silenced INS-1E cells. iPLA2γ/UCP2-mediated uncoupling was alternatively activated by an H2O2 burst, resulting from palmitic acid (PA) β-oxidation, and it was prevented by antioxidants or catalase overexpression. Exclusively, nascent FAs that cleaved off phospholipids by iPLA2γ were capable of activating UCP2, indicating that the previously reported direct redox UCP2 activation is actually indirect. Glucose-stimulated insulin release was not affected by UCP2 or iPLA2γ silencing, unless pro-oxidant activation had taken place. PA augmented insulin secretion via G-protein-coupled receptor 40 (GPR40), stimulated by iPLA2γ-cleaved FAs (absent after GPR40 silencing). INNOVATION AND CONCLUSION: The iPLA2γ/UCP2 synergy provides a feedback antioxidant mechanism preventing oxidative stress by physiological FA intake in pancreatic β-cells, regulating glucose-, FA-, and redox-stimulated insulin secretion. iPLA2γ is regulated by exogenous FA via β-oxidation causing H2O2 signaling, while FAs are cleaved off phospholipids, subsequently acting as amplifying messengers for GPR40. Hence, iPLA2γ acts in eminent physiological redox signaling, the impairment of which results in the lack of antilipotoxic defense and contributes to chronic lipotoxicity.

• MeSH
• antioxidancia farmakologie   MeSH
• beta-buňky účinky léků   MeSH
• fosfolipasy A2, skupina II metabolismus   MeSH
• inzulin sekrece   MeSH
• iontové kanály metabolismus   MeSH
• krysa rodu rattus MeSH
• lipidy toxicita   MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• mitochondriální proteiny metabolismus   MeSH
• mitochondrie účinky léků   MeSH
• nádorové buněčné linie MeSH
• oxidační stres účinky léků   MeSH
• peroxid vodíku metabolismus   MeSH
• receptory spřažené s G-proteiny metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• superoxidy metabolismus   MeSH
• terc-butylhydroperoxid farmakologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Mutations in the filaggrin (FLG) gene are strongly associated with common dermatological disorders such as atopic dermatitis. However, the exact underlying pathomechanism is still ambiguous. Here, we investigated the impact of FLG on skin lipid composition, organization, and skin acidification using a FLG knockdown (FLG-) skin construct. Initially, sodium/hydrogen antiporter (NHE-1) activity was sufficient to maintain the acidic pH (5.5) of the reconstructed skin. At day 7, the FLG degradation products urocanic (UCA) and pyrrolidone-5-carboxylic acid (PCA) were significantly decreased in FLG- constructs, but the skin surface pH was still physiological owing to an upregulation of NHE-1. At day 14, secretory phospholipase A2 (sPLA2) IIA, which converts phospholipids to fatty acids, was significantly more activated in FLG- than in FLG+. Although NHE-1 and sPLA2 were able to compensate the FLG deficiency, maintain the skin surface pH, and ensured ceramide processing (no differences detected), an accumulation of free fatty acids (2-fold increase) led to less ordered intercellular lipid lamellae and higher permeability of the FLG- constructs. The interplay of the UCA/PCA and the sPLA2/NHE-1 acidification pathways of the skin and the impact of FLG insufficiency on skin lipid composition and organization in reconstructed skin are described.

• MeSH
• atopická dermatitida metabolismus   patologie   MeSH
• fosfolipasy A2, skupina II metabolismus   MeSH
• genový knockdown MeSH
• koncentrace vodíkových iontů MeSH
• kůže cytologie   metabolismus   MeSH
• kyselina pyrrolidonkarboxylová metabolismus   MeSH
• kyselina urokanová metabolismus   MeSH
• kyseliny mastné neesterifikované metabolismus   MeSH
• kyseliny metabolismus   MeSH
• lidé MeSH
• metabolismus lipidů fyziologie   MeSH
• Na(+)-H(+) antiport metabolismus   MeSH
• permeabilita MeSH
• proteiny intermediálních filament nedostatek   genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Obesity is believed to be associated with a dysregulated endocannabinoid system which may reflect enhanced inflammation. However, reports of this in human white adipose tissue (WAT) are limited and inconclusive. Marine long-chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs) have anti-inflammatory actions and therefore may improve obesity-associated adipose tissue inflammation. Therefore, fatty acid (FA) concentrations, endocannabinoid concentrations, and gene expression were assessed in subcutaneous WAT (scWAT) biopsies from healthy normal weight individuals (BMI 18.5-25 kg/m2) and individuals living with metabolically healthy obesity (BMI 30-40 kg/m2) prior to and following a 12-week intervention with 3 g fish oil/day (1.1 g eicosapentaenoic acid (EPA) + 0.8 g DHA) or 3 g corn oil/day (placebo). WAT from individuals living with metabolically healthy obesity had higher n-6 PUFAs and EPA, higher concentrations of two endocannabinoids (anandamide (AEA) and eicosapentaenoyl ethanolamide (EPEA)), higher expression of phospholipase A2 Group IID (PLA2G2D) and phospholipase A2 Group IVA (PLA2G4A), and lower expression of CNR1. In response to fish oil intervention, WAT EPA increased to a similar extent in both BMI groups, and WAT DHA increased by a greater extent in normal weight individuals. WAT EPEA and docosahexaenoyl ethanolamide (DHEA) increased in normal weight individuals only and WAT 2-arachidonyl glycerol (2-AG) decreased in individuals living with metabolically healthy obesity only. Altered WAT fatty acid, endocannabinoid, and gene expression profiles in metabolically healthy obesity at baseline may be linked. WAT incorporates n-3 PUFAs when their intake is increased which affects the endocannabinoid system; however, effects appear greater in normal weight individuals than in those living with metabolically healthy obesity.

• MeSH
• časové faktory MeSH
• dospělí MeSH
• dvojitá slepá metoda MeSH
• endokanabinoidy metabolismus   MeSH
• fixní kombinace léků MeSH
• fosfolipasy A2, skupina II metabolismus   MeSH
• fosfolipasy A2, skupina IV metabolismus   MeSH
• kyselina eikosapentaenová aplikace a dávkování   MeSH
• kyseliny arachidonové metabolismus   MeSH
• kyseliny dokosahexaenové aplikace a dávkování   MeSH
• lidé středního věku MeSH
• lidé MeSH
• metabolicky zdravá obezita diagnóza   farmakoterapie   metabolismus   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• podkožní tuk účinky léků   metabolismus   MeSH
• polynenasycené alkamidy metabolismus   MeSH
• potravní doplňky * MeSH
• receptor kanabinoidní CB1 metabolismus   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Geografické názvy
• Anglie MeSH

Acetylcholine (ACh) has been established as a paracrine factor in the anterior pituitary gland, but the receptors mediating ACh action and the cell types bearing these receptors have not been identified. Our results showed that the expression of the nicotinic subunits mRNAs followed the order β2 > β1 = α9 > α4 in cultured rat pituitary cells. The expression of the subunits in immortalized LβT2 mouse gonadotrophs followed the order β2 > α4 = α1. M4 > M3 muscarinic receptor mRNA were also identified in pituitary and LβT2 cells. The treatment of cultured pituitary cells with GnRH down-regulated the expression of α9 and α4 mRNAs, without affecting the expression of M3 and M4 receptor mRNAs, and ACh did not alter the expression of GnRH receptor mRNA. We also performed double immunostaining to show the expression of β2-subunit and M4 receptor proteins in gonadotrophs. Functional nicotinic channels capable of generating an inward current, facilitation of electrical activity, and Ca(2+) influx were identified in single gonadotrophs and LβT2 cells. In both cell types, the M3 receptor-mediated, phospholipase C-dependent Ca(2+) mobilization activated an outward apamin-sensitive K(+) current and caused hyperpolarization. The activation of M4 receptors by ACh inhibited cAMP production and GnRH-induced LH release in a pertussis toxin-sensitive manner. We concluded that multiple cholinergic receptors are expressed in gonadotrophs and that the main secretory action of ACh is inhibitory through M4 receptor-mediated down-regulation of cAMP production. The expression of nicotinic receptors in vitro compensates for the lack of regular GnRH stimulation of gonadotrophs.

• MeSH
• AMP cyklický metabolismus   MeSH
• elektrofyziologie MeSH
• gonadotropní buňky MeSH
• hypofýza metabolismus   MeSH
• imunohistochemie MeSH
• krysa rodu rattus MeSH
• kultivované buňky MeSH
• luteinizační hormon genetika   metabolismus   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• potkani Sprague-Dawley MeSH
• receptor muskarinový M3 genetika   metabolismus   MeSH
• receptor muskarinový M4 genetika   metabolismus   MeSH
• signální transdukce genetika   fyziologie   MeSH
• vápník metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Intramural MeSH

Mast cells and basophils are major effector cells in the immunoglobulin E (IgE)-dependent allergic reactions as well as in the innate immunity. They are distributed throughout the body and, upon allergen exposure, are stimulated via the high affinity IgE receptor (FcepsilonRI) to release several pro-inflammatory mediators such as leukotrienes, immunoregulatory cytokines and histamine. FcepsilonRI-mediated signaling is initiated by tyrosine phosphorylation of FcepsilonRI subunits by Src family kinase Lyn, which is followed by an activation of Syk/Zap family kinase Syk. The activated kinases then in turn phosphorylate and activate other enzymes [phospholipase Cgamma (PLCgamma) isoforms, phosphatidylinositol-3 kinase (PI3K) isoforms, protein kinase C (PKC) isoforms, Bruton's tyrosine kinase (Btk) and others], adaptors [linker for activation of T cells (LAT), Cbl, Grb2 and others] and GTP exchange factors/GTPases (Vav, Ras, Rho, and others), and subsequently induce the mobilization of stored and extracellular Ca(2+). These and other biochemical events lead within seconds and minutes to the secretory response and later to the production of chemokines. This review is focused on the use of tyrosine kinase inhibitors specific for Src family kinases (PP1/PP2, SU6656 and CT5269), Syk kinase (piceatannol, ER-27319 and BAY 61-3606) and Btk (terreic acid and LFM-A13) for a modulation of FcepsilonRI-mediated signaling in mast cells. Potential use of the inhibitors in the treatment of inflammatory and allergy diseases as well as future directions in the development of highly specific tyrosine kinases inhibitors of new generations and their use in an intended modulation of mast cell signaling are discussed.

• MeSH
• alergie farmakoterapie   imunologie   MeSH
• inhibitory enzymů metabolismus   terapeutické užití   MeSH
• lidé MeSH
• receptory IgE fyziologie   metabolismus   MeSH
• signální transdukce imunologie   účinky léků   MeSH
• tyrosinkinasy antagonisté a inhibitory   metabolismus   MeSH
• zánět farmakoterapie   imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH

• Klíčová slova
• Biochemie,
• MeSH
• biochemie MeSH

• Konspekt
• Biochemie. Molekulární biologie. Biofyzika
• NLK Obory
• biochemie