Inhibitory effects of hydrogen on in vitro platelet activation and in vivo prevention of thrombosis formation.
AIMS
Hydrogen (H2) has antioxidant effects. The pharmacologic function of H2 in platelets is not yet clear. Therefore, in this study we sought to investigate the inhibitory effects of H2 on in vitro platelet activation and in vivo prevention of thrombus formation.


MAIN METHODS
After platelets were incubated with H2-rich saline (HRS), platelet adhesion in whole human blood was assessed in fibrinogen-coated perfusion chambers, while rat platelet aggregation induced by ADP, collagen and H2O2 was detected through light transmission aggregometry. The level of P-selectin, thromboxane B2, nitric oxide (NO), malondialdehyde, reactive oxygen species (ROS), cGMP, extracellular signal-regulated kinases 1 and 2 (p-ERK1/2), and fibrinogen binding to platelets were evaluated in vitro. Besides, the in vivo effects were examined in arterio-venous shunt thrombosis, FeCl3-induced artery thrombus formation, and tail bleeding time in mice and rats.


KEY FINDINGS
HRS prolonged tail bleeding time in mice and rats, decreased thrombus weight and prolonged the time to occlusion in rat and mouse thrombosis models in vivo and inhibited platelet adhesion as well as aggregation in vitro. Additionally, HRS decreased P-selectin expression, release of thromboxane B2, ROS, and fibrinogen binding, but enhanced NO levels in H2O2-exposed platelets. HRS also decreased malondialdehyde levels in plasma of the rat arterial thrombosis or H2O2-exposed platelet model. Moreover, HRS increased cGMP level, decreased p-ERK1/2 (diminished with KT5823) in the platelets stimulated by H2O2.


SIGNIFICANCE
These results suggest that H2 has antithrombotic effects, which may be due to its antioxidant property and subsequent inhibition of platelet activation via NO/cGMP/PKG/ERK pathway.
['Wang|Yun|Y|', 'Wu|Ya-Ping|YP|', 'Han|Ji-Ju|JJ|', 'Zhang|Mao-Qing|MQ|', 'Yang|Chen-Xi|CX|', 'Jiao|Peng|P|', 'Tian|Hua|H|', 'Zhu|Chao|C|', 'Qin|Shu-Cun|SC|', 'Sun|Xue-Jun|XJ|', 'Zhang|Han-Ting|HT|', 'Zhao|Xiao-Min|XM|']
D000818:Animals D000975:Antioxidants D015415:Biomarkers D005340:Fibrinogen D006859:Hydrogen D008297:Male D051379:Mice D008810:Mice, Inbred C57BL D015539:Platelet Activation D010973:Platelet Adhesiveness D010974:Platelet Aggregation D051381:Rats D017207:Rats, Sprague-Dawley D013927:Thrombosis
Hydrogen Thrombosis Platelet adhesion Platelet aggregation Reactive oxygen species