GPRP acetate (Gly-Pro-Arg-Pro acetate) is a fibrin polymerization inhibitor that can suppress the interaction between fibrinogen and platelet membrane glycoprotein IIb/IIIa complex (glycoprotein IIb/IIIa receptor) .

Physicochemical Properties

Molecular Formula	C20H35N7O7
Molecular Weight	485.5346
Exact Mass	485.259
CAS #	157009-81-9
Related CAS #	GPRP;67869-62-9
PubChem CID	118986652
Appearance	White to off-white solid powder
Hydrogen Bond Donor Count	6
Hydrogen Bond Acceptor Count	9
Rotatable Bond Count	9
Heavy Atom Count	34
Complexity	725
Defined Atom Stereocenter Count	3
SMILES	CC(=O)O.C1C[C@H](N(C1)C(=O)CN)C(=O)N[C@@H](CCCN=C(N)N)C(=O)N2CCC[C@H]2C(=O)O
InChi Key	ZYTSTPIIKNCGRE-QKWXXBCPSA-N
InChi Code	InChI=1S/C18H31N7O5.C2H4O2/c19-10-14(26)24-8-2-5-12(24)15(27)23-11(4-1-7-22-18(20)21)16(28)25-9-3-6-13(25)17(29)30;1-2(3)4/h11-13H,1-10,19H2,(H,23,27)(H,29,30)(H4,20,21,22);1H3,(H,3,4)/t11-,12-,13-;/m0./s1
Chemical Name	acetic acid;(2S)-1-[(2S)-2-[[(2S)-1-(2-aminoacetyl)pyrrolidine-2-carbonyl]amino]-5-(diaminomethylideneamino)pentanoyl]pyrrolidine-2-carboxylic acid
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	GPRP acetate (0, 2 and 4 mM) stimulates oxidant enzyme production [1].
ln Vitro	GPRP acetate (0, 2 and 4 mM) stimulates oxidant enzyme production [1]. GPRP inhibits ADP-induced platelet aggregation in platelet-rich plasma (PRP).[1] GPRP inhibits fibrinogen polymerization by binding to fibrinogen polymerization sites and modifying glutamine residues in the α- and γ-chains of fibrinogen.[1] In PRP activated via intrinsic pathway, GPRP (2 mM and 4 mM) leads to higher peak levels of free thrombin and larger area under the thrombin generation curve compared to control without GPRP.[1] In the presence of 4 mM GPRP, peak thrombin and area under the curve were 30–40% higher than in absence of GPRP.[1]
ln Vivo	By promoting weight loss and engraftment, GPRP acetate (100 mg/kg; intraperitoneally, once daily for 10 days) dramatically lowers glucose enzyme sodium sulfate (DSS)-induced inflammation [3].
Enzyme Assay	Thrombin generation was measured in platelet-rich plasma (PRP) activated with Actin FSL and CaCl₂. Aliquots were taken at 15-second intervals and mixed with substrate solution containing S-2238. Reaction was stopped with acetic acid, and absorbance was measured at 405 nm. Thrombin activity was expressed as equivalent amount of thrombin, including α₂-macroglobulin–thrombin complex.[1]
Cell Assay	Platelet-rich plasma (PRP) was prepared from whole blood collected in citrate from healthy volunteers. PRP platelet count was adjusted to 250,000/µL using autologous platelet-poor plasma. PRP was incubated with or without GPRP for 60 seconds before activation with Actin FSL and CaCl₂.[1]
Animal Protocol	Animal/Disease Models: C57BL/6 mice dextran sodium sulfate (DSS)-induced colitis [3] Doses: 100 mg/kg Route of Administration: intraperitoneal (ip) injection; 100 mg/kg, one time/day for 10 days Experimental Results: Significant Dramatically inhibited weight loss in colitis mice, diminished DSS-induced mortality and colon length shortening, and diminished tissue damage and inflammatory cell infiltration. Mice with colitis have diminished levels of inflammatory cytokines.
References	[1]. Gly-pro-arg-pro (GPRP) enhances free thrombin. Thromb Res. 1995 Jun 15;78(6):547-50. [2]. Fibrin Polymerization. 1. Alkylating peptide inhibitors of fibrin polymerization. J Med Chem. 1981 Mar; 24(3): 322-7. [3]. Fibrinogen/AKT/Microfilament Axis Promotes Colitis by Enhancing Vascular Permeability. Cell Mol Gastroenterol Hepatol. 2021;11(3):683-696.
Additional Infomation	GPRP is a fibrinogen-related peptide under preclinical investigation as an antithrombotic agent.[1] It inhibits fibrinogen-dependent platelet aggregation and fibrin polymerization.[1] By inhibiting fibrin formation, GPRP reduces adsorption of free thrombin onto fibrin (antithrombin I action), resulting in higher free thrombin levels post-activation.[1] This may limit its potential clinical benefit as an antithrombotic agent despite inhibiting platelet aggregation.[1]

Solubility Data

Solubility (In Vitro)	H2O : ~125 mg/mL (~268.93 mM)
Solubility (In Vivo)	Solubility in Formulation 1: 100 mg/mL (215.14 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.0596 mL	10.2980 mL	20.5960 mL
	5 mM	0.4119 mL	2.0596 mL	4.1192 mL
	10 mM	0.2060 mL	1.0298 mL	2.0596 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.