Modulation of platelet activation and thrombus formation using a pan-PI3K inhibitor S14161

• Published in: PloS one 2014-08, Vol.9 (8), p.e102394
• Main Authors: Yi, Wenxiu, Li, Qiang, Shen, Jian, Ren, Lijie, Liu, Xiaohui, Wang, Qi, He, Sudan, Wu, Qingyu, Hu, Hu, Mao, Xinliang, Zhu, Li
• Format: Article
• Language: English
• Subjects: 1-Phosphatidylinositol 3-kinase; Activation; Adenosine diphosphate; AKT protein; Animals; Benzopyrans - administration & dosage; Benzopyrans - pharmacology; Bioavailability; Biocompatibility; Biology and Life Sciences; Bleeding; Blood clots; Blood platelets; Blood Platelets - drug effects; Blood Platelets - metabolism; Carotid artery; Chemical compounds; Collaboration; Collagen; Collagens; Disease Models, Animal; Dose-Response Relationship, Drug; Ferric chloride; Fibrinogen; Flow cytometry; Glycogen Synthase Kinase 3 - metabolism; Glycogen Synthase Kinase 3 beta; Hematology; Humans; Inhibitors; Integrins - metabolism; Iron chlorides; Kinases; Li, Jian; Male; Medicine and Health Sciences; Mice; Microfluidics; Occlusion; P-selectin; P-Selectin - biosynthesis; Pharmacology; Phosphatidylinositol 3-Kinases - antagonists & inhibitors; Phosphatidylinositol 3-Kinases - metabolism; Phosphorylation; Platelet Activation - drug effects; Platelet Adhesiveness - drug effects; Platelet aggregation; Platelet Aggregation - drug effects; Proteins; Proto-Oncogene Proteins c-akt - metabolism; Signal transduction; Signal Transduction - drug effects; Signaling; Thrombin; Thrombosis; Thrombosis - drug therapy; Thrombosis - metabolism; Toxicity
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0102394

The phosphatidylinositol 3-kinase (PI3K) signaling pathway is critical in modulating platelet functions. In the present study, we evaluated the effect of S14161, a recently identified pan-class I PI3K inhibitor, on platelet activation and thrombus formation. Results showed that S14161 inhibited human platelet aggregation induced by collagen, thrombin, U46619, and ADP in a dose-dependent manner. Flow cytometric studies showed that S14161 inhibited convulxin- or thrombin-induced P-selectin expression and fibrinogen binding of single platelet. S14161 also inhibited platelet spreading on fibrinogen and clot retraction, processes mediated by outside-in signaling. Using a microfluidic chamber we demonstrated that S14161 decreased platelet adhesion on collagen-coated surface by about 80%. Western blot showed that S14161 inhibited phosphorylation of Akt at both Ser473 and Thr308 sites, and GSK3β at Ser9 in response to collagen, thrombin, or U46619. Comparable studies showed that S14161 has a higher potential bioavailability than LY294002, a prototypical inhibitor of pan-class I PI3K. Finally, the effects of S14161 on thrombus formation in vivo were measured using a ferric chloride-induced carotid artery injury model in mice. The intraperitoneal injection of S14161 (2 mg/kg) to male C57BL/6 mice significantly extended the first occlusion time (5.05 ± 0.99 min, n = 9) compared to the vehicle controls (3.72 ± 0.95 min, n = 8) (P0.05). Taken together, our data showed that S14161 inhibits platelet activation and thrombus formation without significant bleeding tendency and toxicity, and considering its potential higher bioavailability, it may be developed as a novel therapeutic agent for the prevention of thrombotic disorders.