platelets

Megakaryocytes/platelets inducing agent being useful in treating diseases involving thrombopenia. Megakaryocytes/platelets inducing agent is an inducing agent for megakaryocytes and/or platelets from pluripotent stem cells.

Carbazochrome (Adchnon) is an antihemorrhagic, or hemostatic, agent that will cease blood flow by causing the aggregation and adhesion of platelets in the blood to form a platelet plug, ceasing blood flow from an open wound. It is hoped that this drug can be used in the future for preventing excessive blood flow during surgical operations and the treatment of hemorrhoids, but research on its effectiveness and the severity of possible side effects remains to be fairly inconclusive. Carbazochrome has been investigated for use in the treatment of hemorrhoids in a mixture with troxerutin.

Lamotrigine (BW430C) is an Anti-epileptic Agent and Mood Stabilizer. The physiologic effect of lamotrigine is by means of Decreased Central Nervous System Disorganized Electrical Activity.

Clopidogrel hydrogen sulfate ((S)-(+)-Clopidogrel bisulfate) , a selective, high-affinity P2Y12 receptor antagonist, suppressess fibrinogen binding to platelets and platelet adhesion and aggregation.

Elaidic acid (trans-Oleic Acid) is the 9-trans isomer of oleic acid. It is a monounsaturated trans-fatty acid which can be found in partially hydrogenated cooking oils. In human platelets incubated with arachidonic acid, elaidic acid inhibits HHT and HETE formation while inducing prostaglandin and thromboxane synthesis.

Arg-Gly-Glu-Ser acetate is a RGD related peptide that is a control for the RGDS activity of fibrinogen binding to activated platelets.

Fibrinogen-Binding Peptide (designed by anticomplementarity hypothesis) is a presumptive peptide mimic of the vitronectin binding site on the fibrinogen receptor. Fibrinogen-Binding Peptide binds fibrinogen and inhibits both the adhesion of platelets to fibrinogen and platelet aggregation, and also inhibits the adhesion of platelets to vitronectin

YRGDS Fibronectin Fragment acetate (YRGDS Fibronectin Fragment acetate (134282-68-1 free base))(134282-68-1 free base) is a fibronectin fragment acetate, an adhesion peptide that displays strong binding affinity to thrombin-stimulated platelets. It is RGD consisting of sequence.

Siguazodan (SKF 94836) is an effective, selective, orally active phosphodiesterase III ((PDE-III)) inhibitor with an IC50 of 117 nM. Siguazodan inhibited phenylephrine induced 5-HT release with an IC50 value of 4.2 μM。 Siguazodan can increase cAMP accumulation in intact platelets, with EC50 of 18.88 μM。

Zoniporide hydrochloride is a selective inhibitor of NHE-1 with IC50 of 14 nM which is >150-fold selectivity versus other NHE isoforms. Zoniporide hydrochloride shows an IC50 of 59 nM for NHE-1-dependent swelling of human platelets.

Atopaxar (E5555), a reversible PAR-1 thrombin receptor antagonist, interferes with platelet signaling. Atopaxar has been investigated for the treatment of Coronary Artery Disease and Acute Coronary Syndrome.

Dibutyryl-cGMP sodium (Bt2cGMP sodium) is a cell-permeable cGMP analog that preferentially activates cGMP-dependent protein kinase (PKG). It inhibits [3H]-arachidonic acid release in human platelets stimulated by gamma thrombin and can induce peripheral analgesia by activating ATP-sensitive K+ channels.

(Rac)-Modipafantis an orally available and selective platelet-activating factor receptor (PAFR) antagonist that inhibits PAF-induced aggregation of washed platelets in rabbits, and can be used to study arthritis and ischemia reperfusion (I R) in the superior mesenteric artery (SMA) of the rat.

Aglafoline inhibits in a concentration-dependent manner the aggregation and ATP release reaction induced in washed rabbit platelets by PAF (platelet-activating factor). The IC50 values of Aglafoline on PAF (3.6 nM)-induced platelet aggregation were about 50 μM.

AACOCF3 (Arachidonyl trifluoromethyl ketone) is a cell-permeable trifluoromethyl ketone analog of arachidonic acid and a potent, selective slow binding inhibitor of the 85-kDa cytosolic phospholipase A2 (cPLA2). By blocking the production of arachidonate and 12-hydroxyeicosatetraenoic acid in calcium ionophore-challenged platelets, AACOCF3 hinders their synthesis. Additionally, AACOCF3 inhibits glucose-induced insulin secretion from isolated rat islets, making it promising for cardiovascular disease research.

Aloxistatin (E64d) is an inhibitor of cysteine protease with blood platelet aggregation inhibiting activity. Aloxistatin is an irreversible, membrane-permeable inhibitor of lysosomal and cytosolic cysteine proteases with the ability to inhibit calpain activity in intact platelets.

Calpeptin is a potent, cell-permeable calpain inhibitor.

Rupatadine (UR-12592) is a potent dual PAF H1 antagonist with Ki values of 0.55 μM in rabbit platelet membranes and 0.1 μM in guinea pig cerebellum membranes.

U-73122 (U73122) , an effective PLC inhibitor, reduces agonist-induced Ca2+ increases in platelets and PMN.

Bivalirudin (BG-8967) is a reversible inhibitor of α- and ζ-thrombin (Kis = 2.56 and 1.84 nM, respectively), enzymes that exhibit high fibrinogen-clotting activities.

Atopaxar, a reversible PAR-1 thrombin receptor antagonist, interferes with platelet signaling. Atopaxar has been investigated for the treatment of Coronary Artery Disease and Acute Coronary Syndrome.

Parmodulin 2 (ML 161) is the inhibitor of protease-activated receptor 1 (PAR1)-mediated platelet activation (IC50: 0.26 μM for the inhibition of platelet P-selectin expression on human platelets). It also inhibits thrombin-induced platelet activation.

TRAP-6 (Thrombin Receptor Activator Peptide 6)(2TFA) is an agonist of protease-activated receptor 1 (PAR1).

Cycloolivil (Isoolivil) is a natural polyphenolic compound found in olive trees that exhibits significant radical scavenging and antioxidant activities. It may prevent thrombotic complications associated with platelet hyperaggregability and serve as a foundational compound for further research.

Cariporide (HOE-642) (HOE-642), an effective NHE1 inhibitor, has inhibitory effects on the degranulation of human platelets, the formation of platelet-leukocyte-aggregates, and the activation of the GPIIb/IIIa receptor (PAC-1).

SCH-37370 is an effective and orally active dual antagonist of platelet-activating factor and histamine. Sch 37370 blocks the binding of [3H]pyrilamine to histamine-H1 receptors in rat brain membranes. Sch 37370 selectively inhibits PAF-induced aggregation of human platelets (IC50 : 0.6 mM) and also competes with PAF binding to specific sites in membrane preparations from human lungs (IC50 : 1.2 mM).

OXSI-2 (Syk Inhibitor) is an inhibitor of Syk with an EC50 of 313 nM and an IC50 of 14 nM. OXSI-2 completely inhibits Adaptor protein LAT Y191 phosphorylation and Syk mediated events in platelets.

RHC 80267 (U-57908) is a selective inhibitor of DAGL, with an IC50 of 4 μM in canine platelets.

Arg-Gly-Glu-Ser TFA, an RGD-related peptide, serves as a control for evaluating the inhibitory activity of RGDS on fibrinogen binding to activated platelets.

Thapsigargicin (Thapsigargicine) acts as an activator for mast cells and leukocytes, prompting histamine release from rat peritoneal mast cells and human basophil leukocytes. Additionally, it elevates cytoplasmic free calcium levels in human blood platelets [1].

Diadenosine pentaphosphate pentaammonium, an endogenous vasoactive purine dinucleotide isolated from thrombocytes, is one component of the diadenosine polyphosphates (ApnA, n=2-7) family. These compounds are found in secretory vesicles, including those in platelets, chromaffin cells, Torpedo synaptic terminals, and brain synaptosomes[1][2].

Prostaglandin H2 (PGH2), initially isolated from the incubation of arachidonic acid with ovine seminal vesicle microsomes, acts as a potent vasoconstrictor. It serves as the precursor for all 2-series prostaglandins (PGs) and thromboxanes (TXs). Moreover, as a TP receptor agonist, PGH2 irreversibly aggregates human platelets at concentrations of 50-100 ng/ml.

14S(15R)-EET methyl ester, an oxylipin derived from arachidonic acid through cytochrome P450 metabolism, demonstrates specific biological activities. It exhibits affinity for isolated guinea pig monocytes, evidenced by a competitive binding assay with a Ki value of 612.5 nM using [3H]14(15)-EET. This compound notably enhances the dilation of precontracted isolated canine epicardial arterioles (EC50= 4 pM) and denuded porcine subepicardial arterioles (EC50= 3 pM), indicating potent vasodilatory effects. Unlike its isomer 14R(15S)-EET, 14S(15R)-EET methyl ester does not inhibit COX activity in enzyme assays or affect isolated platelets, highlighting its distinct functional profile.

(±)-2'-Hydroxy Ceramide (d18:0/18:0) is a sphingomyelin derivative isolated from mammalian platelets upon ADP stimulation [1].

20-Deoxyingenol 3-angelate and ingenol 20-acetate 3-angelate are known as promoters of tumors of mouse skin. 20-Deoxyingenol 3-angelate can induce significant platelet aggregation accompanied by induction of phosphorylation of PKC substrates in platelets,

TPα and TPβ are two isoforms of the human TP receptor, the G protein-coupled receptor (GPCR) that mediates the actions of thromboxane A2 (TXA2). Although their distinct physiological functions have not been fully elucidated, TPβ is believed to be responsible for vascular endothelial growth factor-induced endothelial cell differentiation and migration whereas TPα appears to be the predominant isoform expressed in platelets. CAY10535 is a TP receptor antagonist that shows ~20-fold selectivity for TPβ (IC50 = 99 nM) relative to TPα (IC50 = 1,970 nM) in the inhibition of U46619-mediated Ca2+ mobilization. This compound exhibits relatively poor activity on platelets (IC50 = 985 nM) when inhibiting U-46619-induced platelet aggregation.

13(S)-HOTrE(γ) is the 15-LO product of γ-linolenic acid. It is synthesized in human platelets, but its specific function is not known.

Brovincamine also known as brovincamine fumarate (BV, Sabromin) was used in Japan mainly as an improver of cerebral circulation and metabolism, and also as an inhibitor of the aggregation of platelets through the cyclic AMP pathway in patients with normal tension glaucoma. Brovincamine exerts its action via calcium channels blockade. Brovincamine is also a vasodilator.

Oleic acid-13C is intended for use as an internal standard for the quantification of oleic acid by GC- or LC-MS. Oleic acid is a monounsaturated fatty acid and a major component of membrane phospholipids that has been found in human plasma, cell membranes, and adipose tissue.1,2 It contributes approximately 17% of the total fatty acids esterified to phosphatidylcholine, the major phospholipid class in porcine platelets.1 Oleic acid inhibits collagen-stimulated platelet aggregation by approximately 90% when used at a concentration of 10 μg/ml. It also inhibits fMLF-induced neutrophil aggregation and degranulation by 55 and 68%, respectively, when used at a concentration of 5 μM, similar to arachidonic acid .3 Oleic acid (60 μM) induces release of intracellular calcium in human platelets.4

8-iso-13,14-dihydro-15-keto Prostaglandin F2α (8-iso-13,14-dihydro-15-keto PGF2α) is a metabolite of the isoprostane, 8-isoprostane (8-iso PGF2α), in rabbits, monkeys and humans. 8-iso PGF2α is a PG-like product of non-specific lipid peroxidation. In both humans and monkeys, exogenously infused 8-isoprostane is converted primarily to metabolites having 2 or 4 carbon atoms removed from the top side chain by β-oxidation. A similar pattern is observed when tritiated 8-isoprostane is infused into rabbits. Early in the infusion (within 10 minutes) 8-iso-13,14-dihydro-15-keto PGF2α was a significant component of the metabolite profile, which was comprised mostly of dinor 8-isoprostane metabolites. 8-iso-13,14-dihydro-15-keto PGF2α weakly inhibits the U-46619 or collagen-induced aggregation of human platelets, although a number of the E-series isoprostanes are much more potent in this assay.

KGDS is a synthetic peptide that targets the integrin GPIIb-IIIa on the membrane of activated human platelets, with the amino acid sequence Lys-Gly-Asp-Ser [1].

Arg-gly-glu -Ser(TFA) is a RGD related polypeptide that controls the inhibition of fibrinogen binding to activated platelets by RGDS.

Thrombin receptor agonist peptide (TRAP-14) is a 14-amino acid peptide agonist of the α-thrombin receptor. It induces aggregation of washed platelets as well as platelets in citrated and hirudin plasma. TRAP-14 (100 μM) increases the cytosolic calcium concentration in isolated guinea pig pulmonary smooth muscle cells 5-fold over baseline. It increases pulmonary arterial pressure in isolated guinea pig lung when used at a concentration of 1 μM, which is comparable to the effect induced by 10 nM α-thrombin. TRAP-14 also induces contraction of isolated rat aortic rings and increases endothelin-1 (ET-1) levels in a dose-dependent manner, an effect that is reversed by the ETA antagonist BQ-123 and the nitric oxide synthase (NOS) inhibitor L-NNA .

14S(15R)-EET is an oxylipin and a cytochrome P450 metabolite of arachidonic acid .114S(15R)-EET binds to isolated guinea pig monocytes with a Kivalue of 612.5 nM in a competitive binding assay using [3H]14(15)-EET.2It induces dilation of precontracted isolated canine epicardial arterioles (EC50= 4 pM) and denuded porcine subepicardial arterioles (EC50= 3 pM).3Unlike 14R(15S)-EET, 14S(15R)-EET does not inhibit COX in enzyme assays or isolated platelets.4 1.Daikh, B.E., Lasker, J.M., Raucy, J.L., et al.Regio- and stereoselective epoxidation of arachidonic acid by human cytochromes P450 2C8 and 2C91J. Pharmacol. Exp. Ther.271(3)1427-1433(1994) 2.Wong, P.Y.-K., Lai, P.-S., and Falck, J.R.Mechanism and signal transduction of 14 (R), 15 (S)-epoxyeicosatrienoic acid (14,15-EET) binding in guinea pig monocytesProstaglandins Other Lipid Mediat.62(4)321-333(2000) 3.Zhang, Y., Oltman, C.L., Lu, T., et al.EET homologs potently dilate coronary microvessels and activate BKCa channelsAm. J. Physiol. Heart Circ. Physiol.280(6)H2430-H2440(2001) 4.Fitzpatrick, F.A., Ennis, M.D., Baze, M.E., et al.Inhibition of cyclooxygenase activity and platelet aggregation by epoxyeicosatrienoic acidsJ. Biol. Chem.261(2)15334-15338(1986)

I-SAP is a high affinity TP receptor antagonist. At physiologic pH, I-SAP produces platelet shape change, but not aggregation, with an EC50 value of 9.7 nM. I-SAP binds to human platelets with the maximum binding obtained between pH 6.5 and pH 7.4. In washed human platelets, the Kd for I-SAP is 468 pM at pH 7.4 and 490 pM at pH 6.5.

Produced by neutrophils, macrophages, mast cells, and by transcellular metabolism in platelets, leukotriene C4 (LTC4) is the parent cysteinyl leukotriene formed by the LTC4 synthase-catalyzed conjugation of glutathione to LTA4. It is one of the constituents of slow-reacting substance of anaphylaxis (SRS-A) and exhibits potent smooth muscle contracting activity. LTC4, however, is rapidly metabolized to LTD4 and LTE4, which makes the characterization of LTC4 pharmacology difficult. N-methyl Leukotriene C4 (N-methyl LTC4) is a synthetic analog of LTC4 that is not readily metabolized to LTD4 and LTE4.It acts as a potent and selective CysLT2 receptor agonist exhibiting EC50 values of 122 and > 2,000 nM at the human CysLT2 and CysLT1 receptors, respectively. It has essentially the same potency as LTC4 at both the human and murine receptors CysLT2 receptors. N-methyl LTC4 is potent and active in vivo, causing vascular leak in mice overexpressing the human CysLT2 receptor but not in CysLT2 receptor knockout mice.

Ajoene is a disulfide that has been found inA. sativumand has diverse biological activities, including antibacterial, anticancer, antiplatelet, and antioxidant properties.1,2,3,4It is active against Gram-positive (MICs = 5-160 µg/ml) and Gram-negative bacteria (MICs = 136-200 µg/ml), as well as yeasts (MICs = 10-20 µg/ml).1Ajoene is cytotoxic to mouse melanoma cells (IC50= 18 µM), as well as human colon, lung, mammary, and pancreatic cancer cells (IC50s = 7-41 µM).2It reduces tumor growth in a B16/BL6 mouse model of melanoma when administered at a dose of 25 mg/kg every other day and decreases the number of lung metastases when administered prior to tumor cell inoculation at doses ranging from 1-25 mg/kg. It inhibits ADP- or collagen-induced platelet aggregation in isolated baboon platelets when used at concentrations ranging from 75 to 150 µg/ml and in platelet-rich plasma isolated from baboons when administered at a dose of 25 mg/kg.3Ajoene (25 mg/kg) prevents thrombus formation on damaged arterial walls in heparinized pigs in anin situmodel of thrombogenesis.5It also reduces high-fat diet-induced hepatic steatosis, histopathological markers of liver damage, thiobarbituric acid reactive substances (TBARS) formation, and protein oxidation in a mouse model of non-alcoholic fatty liver disease (NAFLD).4 1.Naganawa, R., Iwata, N., Ishikawa, K., et al.Inhibition of microbial growth by ajoene, a sulfur-containing compound derived from garlicAppl. Environ. Microbiol.62(11)4238-4242(1996) 2.Taylor, P., Noriega, R., Farah, C., et al.Ajoene inhibits both primary tumor growth and metastasis of B16/BL6 melanoma cells in C57BL/6 miceCancer Lett.239(2)298-304(2006) 3.Teranishi, K., Apitz-Castro, R., Robson, S.C., et al.Inhibition of baboon platelet aggregation in vitro and in vivo by the garlic derivative, ajoeneXenotransplantation10(4)374-379(2003) 4.Han, C.Y., Ki, S.H., Kim, Y.W., et al.Ajoene, a stable garlic by-product, inhibits high fat diet-induced hepatic steatosis and oxidative injury through LKB1-dependent AMPK activationAntioxid. Redox Signal.14(2)187-202(2011) 5.Apitz-Castro, R., Badimon, J.J., and Badimon, L.A garlic derivative, ajoene, inhibits platelet deposition on severely damaged vessel wall in an in vivo porcine experimental modelThromb. Res.75(3)243-249(1994)

Calceolarioside A shows potent activity against visceral leishmaniasis. It can induce a dose-related aggregant effect on rabbit platelets, which may be partly related to a calcium-dependent mechanism. Calceolarioside A also has potent antioxidative activi

Foropafant (SR27417) is a highly potent and selective platelet-activating factor (PAF) receptor antagonist (Ki: 57 pM). Foropafant potently inhibits the PAF-induced aggregation of rabbit and human platelets.

Compound 48 80 trihydrochloride (C48 80 trihydrochloride) is a mixture of N-methyl-p-methoxyphenethylamine and formaldehyde produced via a condensation reaction. It acts as a mast cell degranulator and histamine releaser and inhibits phosphatidylinositol-specific phospholipase C activity in human platelets.