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Normal blood
clotting – the kind that happens to seal
up a cut or to repair a ruptured blood
vessel – is vital to survival. But many
people suffer from excessive
thrombosis, a kind of
“micro-coagulation” that goes on
inside your blood vessels all the
time – even when you haven’t been
injured.
The tiny clots (thrombi)
thus formed are normally quickly
digested in a process called
fibrinolysis. If the balance between
clot-forming and clot-dissolving activity
is not maintained, thrombi can block off
tiny blood vessels feeding your heart
(triggering a heart attack) or brain
cells (causing a stroke). Fibrin
(which binds thrombi together) can also
be deposited in your arteries or other
tissues, contributing to atherosclerosis
and leading to local starvation for
oxygen and nutrients. In fact, some
evidence suggests that elevated
fibrinogen leading to the loss of
fibrinolytic balance may actually be the
most important risk factor in
determining your odds of suffering a
heart attack.
Dr. Hiroyuki Sumi of
Japan’s Miyazaki Medical College tested
173 different natural products, looking
for a natural way to support fibrinolytic
activity. He initially thought he had
found his solution in the earthworm
enzyme lumbrokinase, but abandoned
it when studies showed that
lumbrokinase damages the intestinal tract,
causing internal bleeding in older
volunteers.
But then Dr. Sumi’s
team discovered Nattokinase, a
powerful fibrinolytic enzyme naturally
present in natto (a traditional
Japanese fermented food). Nattokinase
has a fibrinolytic “potency matched by no
other enzyme.”
Nattokinase Enhances
Fibrinolysis
In a controlled
study, Dr. Sumi’s team fed a group of
twelve volunteers a large (200 gram)
serving of natto, comparing its
effects on two measures of fibrinolytic
activity with those of unfermented cooked
soybeans. Plain soybeans had no
effect, but Nattokinase consumption
cut the time needed to complete
the clot-dissolving cycle in half.
And after Nattokinase consumption,
total fibrinolytic activity climbed from
zero to 15.2 square millimeters by
the four-hour mark
Dr. Sumi’s team next
performed a longer-term study using
Nattokinase tablets. For eight days,
volunteers took Nattokinase and
had their fibrinolytic activity assessed.
Fibrinolytic activity climbed steadily
over the course of the first four days of
using Nattokinase, reaching a
stable plateau which was maintained for
the rest of the week. At the same time,
markers of dissolved fibrin rose to a
rapid peak and then moved toward a steady
lower level. And when the scientists
tested the key enzyme responsible for
activating fibrinolysis in the body,
tissue plasminogen activator (tPA)
was boosted in men taking Nattokinase.
Nattokinase Restores
Blood Flow
A further experiment
by Dr. Sumi’s group showed that
Nattokinase is potent enough to actually
open up circulatory blockages. The
team first injected a thrombotic cocktail
into lab dogs’ legs, leading to a
thrombus and complete blockage of the
vein. One group of dogs received
Nattokinase tablets, while the others
got a dummy pill. An immediate boost in
the fibrinolytic activity ensued in dogs
receiving Nattokinase; and while
the veins of dogs in the control group
remained blocked off a full 18 hours
after the beginning of the experiment,
those receiving Nattokinase
experienced a complete restoration of
normal blood flow within 5 hours.
Work in humans has
also been reported. In one remarkable
case study, a team of researchers decided
to test the ability of Nattokinase
to treat a case of central
retinal vein occlusion, which occurs
when the blood vessels draining out of
the eye are blocked by a thrombus. The
occlusion had caused edema and bleeding
in the eye, as the dammed-up blood
vessels swelled the eye and caused tiny
vessels to burst. The researchers asked
the man to eat a moderately large (100
gram) serving of natto before
going to bed every night as a
Nattokinase source to dissolve the
clot, instead of “blood-thinning” drugs
like aspirin or warfarin (Coumadin®).
Ten days later,
bleeding from bottom of the eye was
stopped. On day twenty, the man recovered
his vision, and was released from
hospital with instructions to continue
eating his natto (two evenings
each week). Two months later,
Nattokinase had completely cleared the
occlusion.
A Tri-fold Balance
There are at least
three separate mechanisms whereby
Nattokinase exerts its pro-fibrinolytic
effect. Of these three, the direct
fibrinolytic action of Nattokinase,
enzymatically degrading fibrin, appears
to be the least important. The other two
mechanisms are the cleaving of
plasminogen activator-inhibitor type 1
(PAI-1) and the upregulation of
conversion of prourokinase to urokinase.
By shifting the
balance of key regulators of plasminogen-regulating
factors, Nattokinase allows the
body to rev up its natural fibrinolytic
activity, while still maintaining overall
regulation of fibrinolytic balance.
Boosting
Fibrinolysis Naturally
Blockages of large
blood vessels are rare, and require
hospitalization and physician attendance.
Only a fool would reach for a
Nattokinase capsule if there were
signs of a heart attack or stroke. But if
you suffer from hypercoagulability, you
may be looking to enhance your body’s
fibrinolytic function. Quitting
smoking, losing weight, and
getting more exercise enhance
fibrinolysis, while moderate alcohol
consumption, fish oil,
curcumin, and niacin lower
fibrinogen (you may want to use
“flush-free” niacin (inositol
hexanicotinate), not to be confused with
niacinamide).
But while lowering
fibrinogen levels can help prevent
excessive thrombus formation, it doesn’t
address the other side of the
fibrinolytic balance sheet.
Nattokinase’s ability to boost
your body’s own clot-busting activity
makes this natural food enzyme an unique
addition to your supplement armamentarium.
Potency and Purity
The most advanced
Nattokinase supplements boast a
remarkable 20 000 fibrinolytic activity
units per gram (FU/g). Just two such
capsules, containing 36 milligrams of
very pure Nattokinase each, can
deliver a full 1440 FU of activity. Just
as important, with this new technique the
fermentation medium used to produce
Nattokinase contains no soy, so that
the new 20 000 FU/g Nattokinase
supplements are completely soy-free.
Who Should Not Take Nattokinase
Nattokinase
is not a simple “blood thinner:” it works
by breaking down tangled threads of
fibrin, not preventing the clumping
together of platelets, acting to prevent
thrombosis rather than normal
coagulation. Still, fibrin deposition is
an important part of wound healing, and
while excessive fibrin formation
leading to hypercoagulability is a threat
to your health, so is interfering
with fibrin formation when it’s needed to
stop bleeding.
Therefore, people
with bleeding disorders (haemophiliacs,
or those suffering a hemorrhagic
diathesis) should not take
Nattokinase supplements. Nor should
people with ongoing bleeding problems,
such as recent surgery, ulcers,
haemorrhoids, or trauma.
Likewise, people who have suffered
major trauma in the previous month,
ischemic stroke or neurosurgery in
previous six months, or who have
ever had an intracranial bleed
should not use Nattokinase. And
uncontrolled high blood pressure with
a systolic blood pressure of 200 mmHg or
a diastolic pressure of 110 mmHg also
rules out Nattokinase
supplementation.
Also, “blood thinning” drugs, such
as aspirin or warfarin (Coumadin®),
will put some people at
greater risk of a bleeding problem if
they also take Nattokinase. People
taking these drugs should only use
Nattokinase if their prescribing
physician specifically advises them to do
so, and is monitoring their progress
carefully.
References
i. Sumi H, Hamada H,
Nakanishi K, Hiratani H. “Enhancement of
the fibrinolytic activity in plasma by
oral administration of nattokinase.” Acta
Haematol. 1990; 84(3): 139-43.
ii. Nishimura K, Hamamoto J, Adachi K,
Yamazaki A, Takagi S, Tamai T. “Natto
diet was apparently effective in a case
of incipient central retinal vein
occlusion.”
Jpn Rev Clin Ophthalmol.1994;
Sept 88(9):1381-5.
iii. Sumi H, Hamada
H, Tsushima H, Mihara H, Muraki H. “A
novel fibrinolytic enzyme (nattokinase)
in the vegetable cheese Natto; a typical
and popular soybean food in the Japanese
diet.” Experientia. 1987 Oct 15; 43(10):
1110-1.
iv. Urano T, Ihara
H, Umemura K, Suzuki Y, Oike M, Akita S,
Tsukamoto Y, Suzuki I, Takada A. “The
profibrinolytic enzyme subtilisin NAT
purified from Bacillus subtilis cleaves
and inactivates plasminogen activator
inhibitor type 1.” J Biol Chem. 2001 Jul
6; 276(27): 24690-6.
v. Sumi H, Yatagai
C, Kishimoto N. “A very strong activity
of pro-urokinase activator in natto, the
traditional fermented soybean in Japan.”
Fibrinolysis. 1996; 10:31. |