Serine Protease; Granzyme; I-kappaBalpha

Nafamostat mesilate significantly prevents platelet beta-thromboglobulin (beta TG) from being released after 60 and 120 minutes. Neutrophil elastase is not significantly released when using napamostat mesilate (NM); at 120 minutes, the plasma elastase-alpha 1-antitrypsin complex is 0.16 mg/mL in the NM group and 1.24 mg/mL in the control group. The formation of complexes between C1 inhibitor and FXIIa and kallikrein is entirely inhibited by napamostat mesilate.[1] Nafamostat mesilate inhibits a number of proteases that could play a significant role in the pathogenesis of disseminated intravascular coagulation (DIC).At an IC50 of 0.1 μM, napamostat mesilate inhibits the activity of the TF-F.VIIa mediated-F.Xa extrinsic pathway in a concentration-dependent manner.[2] Nafamostat mesilate inhibits the initial-phase transient component of biphasic ASIC3 currents in a concentration-dependent manner with an IC50 value of approximately 2.5 mM.[3]

Nafamostat mesilate (10 mg/kg) prevents scratching brought on by tryptase, but not by serotonin or histamine. The dose-dependent inhibition of scratching induced by intradermal compound 48/80 (10 mg/site) is produced by napamostat mesilate (1–10 mg/kg). Tryptase activity is inhibited in the mouse skin by nafamostat mesilate (10 mg/kg).[4]

Activation of humoral and cellular participants in inflammation enhances the risk of postoperative bleeding and multiple organ damage in cardiopulmonary bypass (CPB). We now compare the effects of heparin alone in combination with nafamostat mesilate (NM), a protease inhibitor with specificity of trypsin-like enzymes, in an extracorporeal circuit which simulates CPB. NM significantly inhibits the release of platelet beta-thromboglobulin (beta TG) at 60 and 120 min. Platelet counts do not differ. ADP-induced aggregation decreases in circuits with NM, which is due to a direct effect of NM on platelet function. NM prevents any significant release of neutrophil elastase; at 120 min, plasma elastase-alpha 1-antitrypsin complex is 0.16 micrograms/ml in the NM group and 1.24 micrograms/ml in the control group. NM completely inhibits formation of complexes of C1 inhibitor with kallikrein and FXIIa. NM does not alter markers of complement activation (C1-C1-inhibitor complex and C5b-9), or indicators of thrombin formation (F1.2). However, at 120 min, thrombin activity as measured by release of fibrinopeptide A is significantly decreased. The data indicate that complement activation during CPB correlates poorly with neutrophil activation and that either kallikrein or FXIIa or both may be more important agonists. The ability of NM to inhibit two important contact system proteins and platelet and neutrophil release raises the possibility of suppressing the inflammatory response during clinical CPB [1].

Cell Viability Assay
Cell Types: MDAPanc-28 cells
Tested Concentrations:80 μg/mL
Incubation Duration: 24 h, 48 h (hours)
Experimental Results: Significantly reduced the cell viability of MDAPanc-28 cells at both 24 hours and 48 hours.

Nafamostat mesilate was dissolved in 5% glucose and was injected intravenously 5 min before pruritogen injection. The skin was isolated from the murine back 5 min after nafamostat administration and the activities of tryptase and chymase in the skin were determined, according to the method described by Wolters et al. (2001). For the assay of tryptase activity, the skin sample was homogenized and sonicated in 10 mM TRIS (tris(hydroxymethyl)aminomethane), pH 6.1, containing 2 M NaCl. The solution was centrifuged at 700×g for 5 min at 4 °C. One microliter of the supernatant (5 mg protein/ml) was added to 49 μl of solution A (0.06 M TRIS, pH 7.8, containing 0.4% dimethyl sufoxide and 30 μg/ml heparin). The cocktail (50 μl) was reacted with 50 μl of 480 μg/ml N-p-Tosyl-Gly-Pro-Arg-p-nitroanilide in solution A at 37 °C for 1 h. Free nitroaniline released was measured colorimetrically at 420 nm. For the assay of chymase activity, skin sample was homogenized and sonicated in solution B (0.45 M TRIS, pH 8.0, containing 0.1% dimethyl sufoxide and 1.8 mM NaCl). The homogenate was centrifuged at 700×g for 5 min at 4 °C. Ten microliters of the supernatant (5 mg protein/ml) was added to 40 μl of solution B. This cocktail (50 μl) was reacted with 50 μl of 2 mg/ml succinyl-Ala-Ala-Pro-Phr-p-nitroanilide acetate in solution B at 37 °C for 1 h. Free nitroaniline released was measured colorimetrically at 420 nm.[2]

Absorption, Distribution and Excretion
Two metabolites of NM, p-guanidinobenzoic acid (PGBA) and 6-amidino-2-naphthol (AN), are renally excreted. Nafamostat accumulates in the kidneys.

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Metabolism / Metabolites
Nafamostat is mainly hydrolyzed by hepatic carboxyesterase and long-chain acyl-CoA hydrolase in human liver cytosol. Main metabolites are p-guanidinobenzoic acid (PGBA) and 6-amidino-2-naphthol (AN) as inactive protease inhibitors.

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Biological Half-Life
Approximately 8 minutes

[1]. Thromb Haemost.1996 Jan;75(1):76-82;
[2]. Eur J Pharmacol.2006 Jan 13;530(1-2):172-8.

Nafamostat is a member of benzoic acids and a member of guanidines.
Nafamostat is a synthetic serine protease inhibitor that is commonly formulated with hydrochloric acid due to its basic properties. It has been used in trials studying the prevention of Liver Transplantation and Postreperfusion Syndrome. The use of nafamostat in Asian countries is approved as an anticoagulant therapy for patients undergoing continuous renal replacement therapy due to acute kidney injury.
Nafamostat is a broad-spectrum, synthetic serine protease inhibitor, with anticoagulant, anti-inflammatory, mucus clearing, and potential antiviral activities. Upon administration, nafamostat inhibits the activities of a variety of proteases, including thrombin, plasmin, kallikrein, trypsin, and Cl esterase in the complement system, and factors VIIa, Xa, and XIIa in the coagulation system. Although the mechanism of action of nafamostat is not fully understood, trypsinogen activation in the pancreas is known to be a trigger reaction in the development of pancreatitis. Nafamostat blocks the activation of trypsinogen to trypsin and the inflammatory cascade that follows. Nafamostat may also decrease epithelial sodium channel (ENaC) activity and increase mucus clearance in the airways. ENaC activity is increased in cystic fibrosis. In addition, nafamostat may inhibit the activity of transmembrane protease, serine 2 (TMPRSS2), a host cell serine protease that mediates viral cell entry for influenza virus and coronavirus, thereby inhibiting viral infection and replication.

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Drug Indication
Used as an anticoagulant in patients with disseminative blood vessel coagulation, hemorrhagic lesions, and hemorrhagic tendencies. It prevents blood clot formation during extracorporeal circulation in patients undergoing continuous renal replacement therapy and extra corporeal membrane oxygenation.

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Mechanism of Action
Nafamostat mesilate inhibits various enzyme systems, such as coagulation and fibrinolytic systems (thrombin, Xa, and XIIa), the kallikrein–kinin system, the complement system, pancreatic proteases and activation of protease-activated receptors (PARs). Nafamostat inhibits lipopolysaccharide-induced nitric oxide production, apoptosis, and interleukin (IL)-6 and IL-8 levels in cultured human trophoblasts. It is shown to act as an antioxidant in TNF-α-induced ROS production.

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Activation of humoral and cellular participants in inflammation enhances the risk of postoperative bleeding and multiple organ damage in cardiopulmonary bypass (CPB). We now compare the effects of heparin alone in combination with nafamostat mesilate (NM), a protease inhibitor with specificity of trypsin-like enzymes, in an extracorporeal circuit which simulates CPB. NM significantly inhibits the release of platelet beta-thromboglobulin (beta TG) at 60 and 120 min. Platelet counts do not differ. ADP-induced aggregation decreases in circuits with NM, which is due to a direct effect of NM on platelet function. NM prevents any significant release of neutrophil elastase; at 120 min, plasma elastase-alpha 1-antitrypsin complex is 0.16 micrograms/ml in the NM group and 1.24 micrograms/ml in the control group. NM completely inhibits formation of complexes of C1 inhibitor with kallikrein and FXIIa. NM does not alter markers of complement activation (C1-C1-inhibitor complex and C5b-9), or indicators of thrombin formation (F1.2). However, at 120 min, thrombin activity as measured by release of fibrinopeptide A is significantly decreased. The data indicate that complement activation during CPB correlates poorly with neutrophil activation and that either kallikrein or FXIIa or both may be more important agonists. The ability of NM to inhibit two important contact system proteins and platelet and neutrophil release raises the possibility of suppressing the inflammatory response during clinical CPB.[1]

C19H17N5O2

347.37

347.138

C, 65.69; H, 4.93; N, 20.16; O, 9.21

81525-10-2

Nafamostat mesylate;82956-11-4;Nafamostat hydrochloride;80251-32-7;Nafamostat formate salt-13C6

4413

Solid powder

1.4±0.1 g/cm3

637.2±65.0 °C at 760 mmHg

339.1±34.3 °C

0.0±1.9 mmHg at 25°C

1.694

1.93

4

4

5

26

552

0

O=C(C1C=CC(NC(N)=N)=CC=1)OC1C=C2C(C=C(C(N)=N)C=C2)=CC=1

MQQNFDZXWVTQEH-UHFFFAOYSA-N

InChI=1S/C19H17N5O2/c20-17(21)14-2-1-13-10-16(8-5-12(13)9-14)26-18(25)11-3-6-15(7-4-11)24-19(22)23/h1-10H,(H3,20,21)(H4,22,23,24)

6-Amidino-2-naphthyl 4-guanidinobenzoate

Nafamostat free base; Nafamostat [INN]; Nafamstat; (6-carbamimidoylnaphthalen-2-yl) 4-(diaminomethylideneamino)benzoate; CHEMBL273264; Y25LQ0H97D; p-Guanidinobenzoic acid ester with 6-hydroxy-2-naphthamidine; Nafamostat; FUT-175; FUT 175; FUT175.

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: >10 mM

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)