With the use of NK or natto extract containing NK, animal studies conducted in several laboratories confirmed that NK has a hypolipidemic effect and significantly reduces high serum levels of triglycerides (TG), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) (10-1). The length of the heparin chain is a factor in determining whether nattokinase can interfere with heparin functions. Taking nattokinase together with medications that lower blood pressure can cause blood pressure to drop too low. Nattokinase enhances the preventive effects of Escherichia coli Nissle 1917 in sodium sulfate-induced colitis with dextran in mice.
Apoptosis is cell death, so by preventing cell death, nattokinase can help limit the effects of a stroke. However, there is still a need to create a safety profile for nattokinase, as it can affect blood flow. According to a study published in the International Journal of Molecular Science, in which a single capsule of nattokinase (2000 FU) was randomly administered to a group of twelve young, healthy men, in just two hours, the concentration of antithrombin in the blood increased significantly. It seems that a high dose of nattokinase may be an effective anticoagulant agent, as it reduces blood clots and, possibly, prevents their formation completely.
Nattokinase, a serine protease from the subtilisin family, is a new allergen contained in natto, a traditional Japanese fermented food. First, two main limitations were the small total sample size and the varied therapeutic dosage of nattokinase in the included studies. These findings help to understand what are the main benefits of nattokinase and what are its shortcomings compared to other remedies for atherosclerosis. There is some evidence to suggest that nattokinase may have neuroprotective and anti-apoptotic properties that stop the progression of ischemic stroke in patients.
Further work will be needed to determine if the positive efficacy of nattokinase on cardiovascular risk factors depends on dose. Overall, the present study with 607 participants found that nattokinase could have a beneficial influence on blood pressure, but no significant improvements were seen in blood lipids and blood glucose. It should be noted that, in the meta-analysis of a relatively high total dose of nattokinase supplements, an increase in HDL-C and a decrease in LDL-C were detected among participants included.