Nattokinase Reduces Brain Infarction, Fibrinogen and Activated Partial Thromboplastin Time against Cerebral Ischemia-Reperfusion Injury
JIUNN-MIN WANG1,4, HSUAN-YING CHEN2, SHIU-MIN CHENG3, SSU-HUA CHEN3, LIN-LAN YANG3 AND FU-CHOU CHENG3*
1. Department of Medical Laboratory, Taichung Veterans General Hospital, Taichung, Taiwan, R.O.C.
2. Stem Cell Center, Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan, R.O.C.
3. Department of Psychology, Asia University, Taichung, Taiwan, R.O.C.
4. Department of Medical Technology, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli, Taiwan, R.O.C.
(Received: August 9, 2011; Accepted: January 19, 2012)
ABSTRACT
Natto is a traditional Japanese food prepared fom fermented soybeans. nattokinase (NK) is considered one of the most active functional ingredients in natto. The present study evaluated the neuroprotective effects of NK in gerbils subjected to focal cerebral ischemia. The gerbils were separated into four groups: control group, ischemic group and two NK groups (4 and 40 mg/day i.g. for 7 days). All gerbils were fed standard chow with or without NK prior to cerebral ischemia. Focal cerebral ischemia was induced by the occlusion of the right common carotid artery and middle cerebral artery for 60 min, followed by reperfusion. Infarct volumes were determined by 2,3,5-triphenyltetrazolium chloride staining. Anti-thrombotic effects of NK, such as fibrinogen,prothrombin time and activated partial thromboplastin time, were also determined. Our data showed that NK significantly reduced infarct volumes by 54-68% (p < 0.01), compared to the ischemic group. Prothrombin time was not significantly different in all groups. However, low dosage NK (4 mg/day) reversed ischemic-induced increase in fibrinogen concentrations and activated partial thromboplastin time. In summary, the data indicated that oral intake of NK for 7 days may alter fibrinolytic activity and provide neuroprotective effects against focal cerebral ischemia in gerbils.
Key words: cerebral ischemia, gerbil, nattokinase, 2,3,5-triphenyltetrazolium chloride