phospholipase a-2

BMS493 is an inverse agonist of the pan-retinoic acid receptor (RAR) that inhibits retinoic acid-induced differentiation, enhances the interaction of nuclear co-inhibitors with RARs, attenuates RA signaling, potentiates TPP-induced toxicity, and inhibits the increase in phospholipase A2 activity.

PACOCF3 (Palmityltrifluoromethylketone) (Palmityltrifluoromet hylketone) is an inhibitor of Ca(2+)-independent phospholipase A2(PLA2) with an IC 50 of 3.8 μM. PACOCF3 alters Ca 2+ signaling in renal tubular cells [1] [2].

Fuzapladib (IS-741) (IS-741) is a phospholipase A2 inhibitor that can inhibits the expression of Mac-1, a cell adhesion molecule. Fuzapladib blocks activation of adhesion molecules (integrin) expressed on the inflammatory cell surface to prevent inflammatory cells from adhering to vascular endothelial cells and infiltrating tissue and to control exacerbation of pancreatitis.

Phospholipase A2 (PLA2) is an enzyme that hydrolyzes fatty acids present in the sn-2 position of phospholipids, and is closely related to lipid metabolism and immune function.

Rhamnetin (beta-Rhamnocitrin), a quercetin derivative found in Coriandrum sativum, has antioxidant and anti-inflammatory activities. Rhamnetin inhibits secretory phospholipase A2.

Varespladib methyl (LY333013), a bioavailable prodrug of Varespladib, is a selective group II secretory phospholipase A2 inhibitor.

Dodecylphosphocholine (DPC) is a substrate-type inhibitor of pancreas phospholipase A2. Dodecylphosphocholine is a detergent.

ONO-RS-082 is a Ca2+-independent phospholipase A2 inhibitor.

Luffariellolide is a terpene compound obtained from the marine sponge Hyrtios communis. It is an inhibitor of human synoviocyte protein phospholipase A2 (HSF-PLA2) and a retinoic acid receptor (RAR) agonist. Luffariellolide inhibits hypoxia (1% O2)-induced HIF-1 activation and inhibits cell growth.

SecretedPhospholipaseA2-IIA, Human (EC 3.1.1.4), a member of the antimicrobial peptide family, functions by hydrolyzing phospholipids, thereby releasing lysophospholipids and fatty acids. It is particularly proficient at hydrolyzing bacterial membranes.

Triamcinolone (Aristocort) is a synthetic glucocorticoid with anti-inflammatory and immunomodulating properties. Upon cell entry, triamcinolone binds to and activates the glucocorticoid receptor, which leads to translocation of the ligand-receptor complex to the nucleus and induces expression of glucocorticoid-responsive genes such as lipocortins. Lipocortins inhibit phospholipase A2, thereby blocking the release of arachidonic acid from membrane phospholipids and preventing the synthesis of prostaglandins and leukotrienes, both mediators of inflammation. In addition, pro-inflammatory cytokine production, including interleukin (IL)-1and IL-6, and the activation of cytotoxic T-lymphocytes is also inhibited. T-cells are prevented from making IL-2 and proliferating. This agent also decreases the number of circulating lymphocytes, induces cell differentiation, and stimulates apoptosis through increasing Ikappa-B expression and curtailing activation of nuclear factor (NF)kappa-B.

3-Nitrocoumarin (3-nitrochromen-2-one) (3-NC) is a potent and selective Phospholipase C-γ (PLCγ) inhibitor.

Lp-PLA2-IN-2 is a selective and potent lipoprotein-associated phospholipase A2 (Lp-PLA2) inhibitor, with an IC50 of 120 nM for recombinant human Lp-PLA2.

2-(E-2-decenoylamino)ethyl 2-(cyclohexylethyl) sulfide inhibits stress-induced ulcers by maintaining phospholipase A2 and prostaglandin E2 levels in rats subjected to water immersion-restrained stress-induced ulceration.

2-Methylbutyrylcarnitine (chloride) acts as a gut microbial metabolite that targets integrin α2β1 on platelets, facilitating the activation of cytosolic phospholipase A2 (cPLA2) and enhancing platelet hyperresponsiveness. This compound further augments platelet hyperreactivity and promotes thrombus formation in mice. It is also characterized as a branched-chain acylcarnitine.

GK241 (compound 31a-c), a 2-oxoamide-based compound, exhibits inhibitory activity against group IIA secretory phospholipase A2 (GIIA sPLA2) in humans and mice, with IC50 values of 143 nM and 68 nM, respectively. The mechanism of inhibition has been explored through molecular dynamics simulations.

OBAA is a potent inhibitor of phospholipase A2 (PLA2) with an IC 50 of 70 nM. OBAA blocks Melittin-induced Ca 2+ influx in Trypanosoma brucei with an IC 50 of 0.4 μM [1] [2] [3].

Abroquinone A, a natural isoflavanquinone, has been shown to block cytosolic phospholipase A(2) and 5-lipoxygenase activation in neutrophils, it may have pharmaceutical potential as an antiallergic agent.

Amentoflavone (3',8''-Biapigenin), as a potent inhibitor of CYP3A4 and CYP2C9, can interact with many other medications. CYP3A4 and CYP2C9 are proteins used for drug metabolism in the body. Amentoflavone also is an inhibitor of human cathepsin B. It has antimalarial activity in trials significant affinities towards the Delta-1, kappa opioid receptors (as an antagonist) and binds to benzodiazepine receptors. Amentoflavone may be a potential lead for a new type of anti-inflammatory agents having the dual inhibitory activity of group II phospholipase A2 and cyclooxygenase. Amentoflavone and quercetin differentially exerted suppression of PGE2 biosynthesis via downregulation of COX-2/iNOS expression.

12-HETE ((±)12-HETE) is a modulator of PGE2, with both anti-thrombotic and pro-thrombotic effects, inducing PGE2 release and COX-2 expression via phospholipase A2 (sPLA2-IIA) inducers. It is also a neuroregulator activating retinal cell endothelial dysfunction in diabetic retinopathy.

PGBx is a mixture of oligomers of PGB1 with a molecular weight of 1,000-1,500. It has antioxidant and free radical trapping activity that was first studied in isolated mitochondria.1 PGBx has anti-inflammatory and cytoprotective activity which may be attributed to inhibition of the 14 kDa sPLA2.2,3 At a dose of 1 mg/kg, PGBx significantly reduces the incidence of ulcers in rats.2References1. Polis, B.D., Polis, E., and Kwong, S. Protection and reactivation of oxidative phosphorylation in mitochondria by a stable free-radical prostaglandin polymer (PGBΧ). Proceedings of the National Academy of Sciences of the United States of America 76, 1598-1602 (1979).2. Kumashiro, R., Devlin, T.M., Kholoussy, A.M., et al. Prostaglandin BΧ in the prevention of stress ulcers in rats. International Surgery 70, 247-250 (1985).3. Franson, R.C., Rosenthal, M.D., and Regelson, W. Mechanism(s) of cytoprotective and anti-inflammatory activity of PGB1 oligomers: PGBx has potent anti-phospholipase A2 and anti-oxidant activity. Prostaglandins, Leukotrienes and Essential Fatty Acids 43, 63-70 (1991). PGBx is a mixture of oligomers of PGB1 with a molecular weight of 1,000-1,500. It has antioxidant and free radical trapping activity that was first studied in isolated mitochondria.1 PGBx has anti-inflammatory and cytoprotective activity which may be attributed to inhibition of the 14 kDa sPLA2.2,3 At a dose of 1 mg/kg, PGBx significantly reduces the incidence of ulcers in rats.2 References1. Polis, B.D., Polis, E., and Kwong, S. Protection and reactivation of oxidative phosphorylation in mitochondria by a stable free-radical prostaglandin polymer (PGBΧ). Proceedings of the National Academy of Sciences of the United States of America 76, 1598-1602 (1979).2. Kumashiro, R., Devlin, T.M., Kholoussy, A.M., et al. Prostaglandin BΧ in the prevention of stress ulcers in rats. International Surgery 70, 247-250 (1985).3. Franson, R.C., Rosenthal, M.D., and Regelson, W. Mechanism(s) of cytoprotective and anti-inflammatory activity of PGB1 oligomers: PGBx has potent anti-phospholipase A2 and anti-oxidant activity. Prostaglandins, Leukotrienes and Essential Fatty Acids 43, 63-70 (1991).

C2 Phytoceramide is a bioactive semisynthetic sphingolipid that inhibits formyl peptide-induced oxidant release (IC50 = 0.38 μM) in suspended polymorphonuclear cells. It increases COX-2 protein levels 15-fold through ERK signaling. It induces death of keratinocytes (20% viability) with an ED50 value of 30 μM, the same concentration at which 35% of cells in a TUNEL assay are apoptotic. C2 Phytoceramide also has antiproliferative effects in CHO cells, with greater than 80% cytotoxicity achieved at a concentration of 20 μM, and induces internucleosomal DNA fragmentation. In addition, it inhibits the activation of phospholipase D (PLD) mediated by muscarinic acetylcholine receptors in vitro.

The phosphatidylinositol (PtdIns) phosphates represent a small percentage of total membrane phospholipids. However, they play a critical role in the generation and transmission of cellular signals. PtdIns-(1,2-dioctanoyl) is a synthetic analog of natural phosphatidylinositol (PtdIns) containing C8:0 fatty acids at the sn-1 and sn-2 positions. The compound features the same inositol and diacyl glycerol (DAG) stereochemistry as that of the natural compound. The short fatty acid chains of this analog, compared to naturally-occurring PtdIns, gives it different physical properties including high solubility in aqueous media. PtdIns are phosphorylated to mono- (PtdIns-P; PIP), di- (PtdIns-P2; PIP2), and triphosphates (PtdIns-P3; PIP3). Hydrolysis of PtdIns-(4,5)-P2 by phosphoinositide (PI)-specific phospholipase C generates inositol triphosphate (IP3) and DAG which are key second messengers in an intricate biochemical signal transduction cascade.

The phosphatidylinositol (PtdIns) phosphates represent a small percentage of total membrane phospholipids. However, they play a critical role in the generation and transmission of cellular signals. PtdIns-(3,4,5)-P3, also known as PIP3, is resistant to cleavage by PI-specific phospholipase C (PLC). Thus, it is likely to function in signal transduction as a modulator in its own right, rather than as a source of inositol tetraphosphates. PIP3 can serve as an anchor for the binding of signal transduction proteins bearing pleckstrin homology (PH) domains. Protein binding to PIP3 is important for cytoskeletal rearrangement and membrane trafficking. PtdIns-(3,4,5)-P3 (1,2-dihexanoyl) is a synthetic analog of natural PIP3 with C6:0 fatty acids at the sn-1 and sn-2 positions. The compound features the same inositol and diacylglycerol (DAG) stereochemistry as that of the natural compound. The short fatty acid chains of this analog give it different physical properties from naturally-occurring PIP3, including higher solubility in aqueous media.