Nafamostat mesilate attenuates neuronal damage in a rat model of transient focal cerebral ischemia through thrombin inhibition

Abstract

Evidence suggests that thrombin, a blood coagulation serine protease, mediates neuronal injury in experimental cerebral ischemia. Here, we test the hypothesis that nafamostat mesilate, a serine protease inhibitor, may ameliorate ischemia-induced neuronal damage through thrombin inhibition after ischemic stroke. Focal ischemia was induced in adult Sprague-Dawley rats by occlusion of the middle cerebral artery for 2 hours followed by 22 hours of reperfusion. The administration of nafamostat mesilate during ischemia and reperfusion reduced the brain infarct volume, edema volume and neurological deficit. Thrombin expression and activity in the ipsilateral striatum were increased after ischemia, whereas the administration of nafamostat mesilate significantly inhibited thrombin expression and activity. Immunostaining showed that the majority of thrombin was expressed in neurons. TUNEL staining showed that nafamostat mesilate reduced the number of dying cells during ischemia. A rat behavioral test showed that nafamostat mesilate treatment significantly improved the learning ability of ischemic rats. These results suggest that nafamostat mesilate may have a potential therapeutic role for neuroprotection against focal cerebral ischemia through thrombin inhibition.

Synthesis and biological evaluation of 3-([1,2,4]triazolo[4,3-a]pyridin-3-yl)-4-(indol-3-yl)-maleimides as potent, selective GSK-3β inhibitors and neuroprotective agents

“…The widely accepted transient middle cerebral artery occlusion (tMCAO) stroke model was used in this study. 18 As shown in Figure 5, compound 7f-treated rats displayed significantly smaller average infarct size and the neurological deficit than vehicle-treated rats. There was no statistical difference in infarct size and the neurological deficit between vehicle-treated and saline-treated rats (data not shown) ruling out a protective effect of the vehicle.…”

“…18 The external carotid artery was isolated and coagulated, a monofilament nylon suture (diameter of approximately 0.26 mm) with a round tip was inserted into the internal carotid artery through the external carotid artery stump, occluding the middle cerebral artery for 2 h. After occlusion, the animals were reanesthetized and the filament was withdrawn to restore blood flow. Body temperature was regulated at 37°C with a temperature control system.…”

“…Sections were inspected for the presence of macroscopic intracranial hemorrhage, then stained with 2% 2,3,5-triphenyltetrazolium chloride (TTC) for 20 min at 37°C, fixed with 10% formalin, and evaluated for infarct size by morphometric analysis (image-pro plus) as described. 18 Total infarct volume was expressed as a percentage of the volume of the all sectional area to the lesion. The neurological scores were evaluated 24 h after the MCAO using a scoring system as previously reported.…”

Nafamostat Mesilate Improves Neurological Outcome and Axonal Regeneration after Stroke in Rats

“…Besides, NM could dampen neuronal damage by modulating TRPM7 current, which is independent of its protease inhibitory effect [11]. Recently, we have demonstrated that NM attenuates neuronal damage in the rat model of ischemic stroke [12]. However, how NM improves functional recovery after ischemic stroke remains unknown.…”

Identification of berberine as a direct thrombin inhibitor from traditional Chinese medicine through structural, functional and binding studies

“…Thrombin is widely disseminated throughout the vascular system and participates in a variety of physiological and disease processes, such as blood clotting, anticoagulation, thrombosis-fibrinolysis, stroke, neurodegenerative diseases, neuroprotection, and cancer invasion and metastasis2345. Platelet activation by thrombin is a critical factor leading to blood stasis syndrome.…”