Nattokinase

By Kenneth Proefrock, NMD

Nattokinase is a potent fibrinolytic enzyme that is extracted and purified from a traditional Japanese soy cheese, Natto. Natto is produced by adding the bacteria Bacillus natto to boiled soybeans and allowing the mixture to ferment. It has been used in Japan for over 1000 years; it has a very unique taste and place in Japanese cuisine. The nattokinase enzyme is found in the sticky “threads” associated with natto. It was in these threads that the discoverer of nattokinase, Dr. Hiroyuki Sumi, first found this remarkable enzyme. Dr. Sumi was working as a researcher at Chicago University Medical School in 1980 looking for potential thrombolytic agents, and found nattokinase to have a potency matched by no other enzyme.¹

Nattokinase is a 275 amino acid peptide with a similar structure and function to the endogenous enzyme plasmin. Plasmin is a thrombolytic enzyme that is produced in the insides of the blood vessels, in the endothelium. It provides a protective function by breaking down the bundles of fibrin and fibrinogen that cause clots to form in the vessel, restricting blood flow. Most of the clinically useful clot disintegrators in medicine work by enhancing the effects of plasmin on blood clots; these include tissue plasminogen activator, urokinase, and streptokinase. These medications, unfortunately, have to be given intravenously because they are inactivated by the digestive tract. Nattokinase also has its effects on blood clots by enhancing plasmin’s activity, it, however, is active orally.² In addition to being orally active, nattokinase also has a much longer half-life than many of the intravenously administered agents, this helps ensure the breakdown of existing clots and helps keep the blood thin enough to prevent future clots.³ Relatively thinner blood takes less pressure to move through blood vessels and is more easily perfused into the end tissues. These are two phenomenon that allow nattokinase the ability to help reduce systolic blood pressure and restore a certain healthy vigor to those tissues that have been compromised by poor blood flow.⁴

Nattokinase has also been shown to suppress the thickening of blood vessels related to arteriosclerosis, or hardened arteries.^5,6 The implications of this finding are huge as it pertains to heart disease. The progressive hardening of the arteries in response to inflammatory events that a cardiovascular system is exposed to is one of the leading causes for hypertension, stroke and congestive heart failure. Senile dementia is most often caused by inadequate perfusion of the brain with oxygenated blood. This can result from poor blood flow through narrowed and hardened cerebral blood vessels, it can also result from “mini-strokes” that are a result of focal areas of sclerosis or scarring where adequate blood was simply not available to keep the tissue alive. As the arteries and arterioles harden, they are less able to expand to accommodate the bolus of blood that the heart pushes through the system with each heartbeat. It is this bolus that one is feeling when you check your pulse in your wrist or neck. Nattokinase holds the promise of being able to reverse these age related oxidative changes, both by suppressing further hardening of the intimal layer of blood vessels as well as by ensuring better tissue perfusion by providing a thinner blood. This same scenario is also true in the heart muscle that has suffered ischemia, in many cases for years of a person’s life, by providing better perfusing blood and suppressing the hardening of the intimal layers of the cardiac blood vessels one may be able to restore a certain degree of cardiac function.

Heart disease is the number one killer in this country, 40% of the people who will die this year will die from heart disease. It is well established and well known that this is a disease of lifestyle, unfortunately, by the time that a person begins to exhibit symptoms related to their illness, the damage has already been done. We would all do well to adopt a more healthful diet, one rich with fruits and vegetables with clean, low-fat protein sources. We would all do well to adopt a regular regimen of exercise and turn our backs on the sedentary, yet stressful lifestyles that propel us towards heart disease. The reality is that, for any number of reasons, few of us ever engage these changes in lifestyle and heart disease remains the number one cause of death. Nattokinase provides a very real intervention that holds the possibility of helping many people regardless of lifestyle changes.

References
1. Sumi H. et al A novel fibrinolytic enzyme (Nattokinase) in the vegetable cheese natto: A typical and popular soybean food found in the Japanese diet. Experimentia 1987;1110-1111.
2. Sumi H et al, Enhancement of the fibrinolytic activity in plasma by oral administration of Nattokinase. Acta Haematol 1990;84:139-143.
3. Urano T et al, The profibrinolytic enzyme subtilisin NAT purified from Bacillus subtilis cleaves and inactivates plasminogen activator inhibitor type 1. J Biol Chem 2001;27:24690-6.
4. Guo J, Sun Y, Su Y, Preparation of natto and its function in healthcare. Zhong Yao Cai 2002 Jan;25(1):61-4.
5. Suzuki Y, Kondo K, et al, Dietary supplementation with fermented soybeans suppresses intimal thickening. Nutrition 2003 Mar;19(3):261-4.
6. Suzuki Y, Kondo K, et al, Dietary supplementation of fermented soybean, natto, suppresses intimal thickening and modulates the lysis of mural thrombi after endothelial injury in rat femoral artery. Life Sci 2003 Jul 25;73(10):1289-98.