Neuroprotective Effect of SolCD39, a Novel Platelet Aggregation Inhibitor, on Transient Middle Cerebral Artery Occlusion in Rats

Abstract

Background and Purpose-SolCD39 is a soluble form of recombinant human ecto-ATP/ADPase (NTPDase1) and represents a new class of antithrombotic agents. SolCD39 blocks and reverses platelet activation, preventing recruitment of additional platelets into a growing thrombus. The purpose of this study was to examine the effect of solCD39 on neurological deficit, infarct size, and extent of edema after transient middle cerebral artery occlusion (MCAO) in rats. Methods-Physiologically controlled Sprague-Dawley rats underwent 2-hour MCAO by retrograde insertion of an intraluminal suture coated with poly-L-lysine. The agent (solCD39) was administered intravenously before MCAO or at 1-hour or 3-hour recirculation. Other groups received vehicle (Tris-buffered saline) or human albumin (as a "positive" neuroprotective control; 25%, 0.5% of body weight) at 1-hour recirculation. Neurological status was evaluated during occlusion (at 60 minutes) and daily for 3 days after MCAO. Brains were perfusion-fixed at 72 hours, and infarct volumes and brain swelling were determined. Results-Pretreatment with solCD39 significantly improved the neurological score at 72 hours compared with the vehicle group (4.4Ϯ0.6 versus 7.6Ϯ0.6, respectively; Pϭ0.008). Cortical infarct areas were significantly reduced at multiple levels by pretreatment with solCD39. Total striatal infarct area was also significantly reduced compared with vehicle by both solCD39 pretreatment (48% mean reduction) and solCD39 treatment at 3-hour recirculation (51% mean reduction). Treatment with SolCD39 significantly reduced total infarct volume (corrected for brain swelling) by an average of 71% to 72% when administered either before ischemia or at 3 hours of recirculation compared with vehicle. Treatment with albumin significantly reduced neurological score and total, cortical, and subcortical infarction at multiple levels, as expected. Conclusions-Treatment

Pharmacological Induction of Ischemic Tolerance by Glutamate Transporter-1 (EAAT2) Upregulation

“…To compensate for the effect of brain edema, corrected infarct volumes were calculated as previously described using: Corrected infarct areaϭMeasured infarct areaϫ{1Ϫ[(Ipsilateral hemisphere areaϪContralateral hemisphere area)/Contralateral hemisphere]}. 12 Infarct volumes were expressed as percentages of total hemispheric volumes.…”

Adenovirus-Mediated Transfer of Human Placental Ectonucleoside Triphosphate Diphosphohydrolase to Vascular Smooth Muscle Cells Suppresses Platelet Aggregation In Vitro and Arterial Thrombus Formation In Vivo

“…Animal studies have shown that a new soluble form of the extracellular region of CD39 (solCD39) has systemic antithrombotic effects 30,31 ; however, antiplatelet therapy also tends to induce systemic bleeding. 2 This is an important limitation to clinical applicability and indicates a potential advantage of local gene transfer into injured vessels.…”

Engineered human soluble calcium-activated nucleotidase inhibits coagulation in vitro and thrombosis in vivo

“…Belayev et al [28] also reported that a soluble form of CD39/NTPDase1 nucleotidase utilized in a rat model of middle cerebral artery occlusion was capable of significantly reducing total infarct areas at various coronal levels when administered, both before ischemia and after 3 hours of recirculation. Thus, soluble nucleotidase enzymes appear to be very attractive candidates for therapeutic use in thrombotic pathologies.…”

“…One of these enzymes, NTPDase1 (also known as CD39 [25][26][27]) is present in vascular endothelial cells and functions in maintaining hemostasis. The therapeutic utility of a soluble form of CD39/NTPDase1 apyrase has been demonstrated in a variety of cardio-and cerebrovascular disorders, including middle cerebral artery occlusion [1,28], intestinal ischemia-reperfusion injury [29], and arterial balloon injury [30,31]. The NTPDase1 enzyme acts via the same mechanism as the SCAN enzymes used in the present study -inhibition of platelet aggregation and clotting by hydrolysis of the platelet aggregation agonist, ADP, thereby preventing activation of the platelet purinergic receptors, which normally lead to platelet activation, shape change, aggregation, and clotting.…”