A novel fibrinolytic enzyme (nattokinase) in the vegetable cheese Natto; a typical and popular soybean food in the Japanese diet

A strong fibrinolytic activity was demonstrated in the vegetable cheese Natto, which is a typical soybean food eaten in Japan. The average activity was calculated at about 40 CU (plasmin units)/g wet weight. This novel fibrinolytic enzyme, named nattokinase, was easily extracted with saline. The mol. wt and pI were about 20,000 and 8.6, respectively. Nattokinase not only digested fibrin but also the plasmin substrate H-D-Val-Leu-Lys-pNA (S-2251), which was more sensitive to the enzyme than other substrates tried. Diisopropyl fluorophosphate and 2,2,2-trichloro-1-hydroxyethyl-o,o-dimethylphosphate strongly inhibited this fibrinolytic enzyme.     

Novel aspects and new roles for the serine protease plasmin

The serine protease plasmin is distributed throughout the human body in the form of the zymogen plasminogen. The plasminogen activation system is mostly recognized for its fibrinolytic activity but is also upregulated in chronic inflammatory diseases, including atherosclerosis and arthritis. Plasmin can bind to a variety of cells, including monocytes, through low-affinity binding sites and triggers aggregation of neutrophils, platelet degranulation and arachidonate release from endothelial cells. In monocytes, plasmin elicits full-scale proinflammatory activation, including lipid mediator release, chemotaxis and cytokine expression, as well as induction of other proinflammatory genes. The effects of plasmin are specific, require the active catalytic center and can be antagonized by lysine analogues, implying binding of the plasmin molecule to the cell membrane through its lysine binding sites. In view of the upregulation of the fibrinolytic genes in chronic inflammatory diseases, cell activation by plasmin is likely to play a major pathophysiological role, a view that is further supported by data from transgenic mice.Received 9 September 2003; received after revision 4 October 2003; accepted 13 October 2003     

Deficiency of fibrinolytic enzyme activities in the serum of patients with Alzheimer-type dementia

Previously we reported that there is a kallikrein deficiency in the cerebral tissue of patients with Alzheimer-type dementia. The present study was performed to investigate protease changes in the serum of these patients. The results showed that the kallikrein activity was normal, but that the activities of plasmin and urokinase were significantly low. The present findings indicate a derangement in the clotting and fibrinolytic systems in Alzheimer patients.     

Deficiency of fibrinolytic enzyme activities in the serum of patients with Alzheimer-type dementia.

Previously we reported that there is a kallikrein deficiency in the cerebral tissue of patients with Alzheimer-type dementia. The present study was performed to investigate protease changes in the serum of these patients. The results showed that the kallikrein activity was normal, but that the activities of plasmin and urokinase were significantly low. The present findings indicate a derangement in the clotting and fibrinolytic systems in Alzheimer patients.     

Characterization and antithrombotic action of tissue plasminogen activator

Summary An extractive fibrinolytic enzyme has been characterized and found to belong to the class of vascular plasminogen activators. The agent has been found to have an antithrombotic action in the rabbit.Provided by Dr L. Dussourd d'Hinterland, Laboratoires Pierre Fabre, Castres, France. 1000 units have a fibrinolytic activity of about 15 PU urokinase.     

Intrauterine device increases the fibrinolytic activity of the rat endometrium at deciduation, a new aspect of its contraceptive effect.

The fibrinolytic activity of the endometrium of the two uterine horns in the rat was histochemically determined. One of the horns contained a plastic-IUD, the other served as control. The endometrium of the control horn was almost inactive in contrast with that of the IUD-horn in which fibrinolytic activity was apparent. The fibrinolytic activity induced by the IUD might be involved in the prevention of ova implantation.     

Intrauterine device increases the fibrinolytic activity of the rat endometrium at deciduation,a new aspect of its contraceptive effect

Summary The fibrinolytic activity of the endometrium of the two uterine horns in the rat was histochemically determined. One of the horns contained a plastic-IUD, the other served as control. The endometrium of the control horn was almost inactive in contrast with that of the IUD-horn in which fibrinolytic activity was apparent. The fibrinolytic activity induced by the IUD might be involved in the prevention of ova implantation.Supported by grants from WHO No. H 9/181/126 C and the Swedish Medical Research Council (No. B 76-17X-04523-02A).     

Héparine et fibrinolyse

Summary In vitro study of the influence of heparin on fibrinolysis. Heparin, in high concentration, inhibits plasminogen activation by streptokinase or urokinase. The presence of some plasmatic component is herefore required. Heparin has no effect on the fibrinolytic activity of bovine plasmin orAspergillus protease. Heparin does not promote fibrinolysis.

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Travail réalisé avec l'aide financière de l'U.S. National Institute of Health (Grant H-5698).     

Substance P-induced fibrinolysis in the forearm of healthy humans

Physiological saline with or without substance P (50 ng/ml) was infused into the humeral artery in 6 healthy males. Indices of fibrinolytic activity (whole blood diluted lysis time, euglobulin lysis time, lysis areas in non-heated fibrin plates produced by plasma or euglobulin precipitate, plasminogen plasma levels, ₂-macroglobulin, Cl-inhibitor, and ₂-antiplasmin) were evaluated in the homolateral antecubital vein before and after 5 min of substance P or saline infusion. After substance P the fibrinolytic activity increased, as can be seen from the shortening of lysis times (p<0.01) and enlargement of the lysis areas (p<0.01). A reduction of plasminogen plasma levels (p<0.01), associated with a decrease in ₂-anitplasmin (p<0.01), was also found. Alpha₂-macroglobulin and Cl-inhibitor were instead unaltered by the peptide. The saline infusion, on the other hand, was unable to modify any of the examined indices. We concluded that exogenous substance P given intra-arterially increases fibrinolytic activity in locally-sampled venous blood through a mechanism which remains to be elucidated.     

Local haemostasis in brain tumours.

The thromboplastic activity and the fibrinolytic activity were examined in 7 human meningiomas and 6 gliomas obtained at neurosurgery. Two different haemostatic patterns emerged, meningiomas having lower thromboplastic and higher fibrinolytic activity than that of gliomas. This difference might help to explain the better haemostatic capacity of gliomas during and after operation than that of meningiomas.     

Local haemostasis in brain tumours

Summary The thromboplastic activity and the fibrinolytic activity were examined in 7 human meningiomas and 6 gliomas obtained at neurosurgery. Two different haemostatic patterns emerged, meningiomas having lower thromboplastic and higher fibrinolytic activity than that of gliomas. This difference might help to explain the better haemostatic capacity of gliomas during and after operation than that of meningiomas. Supported by Tore Nilson's Fund for Medical Research.     

Recent observations on the structure and the properties of yeast NMN adenylyltransferase

Summary A homogeneous preparation of yeast NMN adenylyltransferase (EC 2.7.7.1) showed microheterogeneity, which was revealed by FPLC (Fast Protein Liquid Chromatography) ion exchange chromatography. The resolved components have been characterized with respect to electrophoretic behavior and adenine content. The results led to a hypothesis about a possible role of poly(ADP-ribosylation) in modulating the enzyme activity.     

The effect of the anabolic steroid stanozolol on tissue plasminogen activator activity and plasmin inhibition in the rat

Summary The anabolic steroid stanozolol administered orally in male Sprague-Dawley rats induced a dose- and time-dependent increase in tissue plasminogen activator activity. The increase was highest in lung, lowest in heart, and intermediate in aorta and kidney. A slight increase in plasmin inhibition was noted only in the heart.This study was partially supported by a grant from the Atherosclerosis and Thrombosis Research Committee of the Austrian Academy of Sciences.     

The plasmin–antiplasmin system: structural and functional aspects

The plasmin–antiplasmin system plays a key role in blood coagulation and fibrinolysis. Plasmin and α₂-antiplasmin are primarily responsible for a controlled and regulated dissolution of the fibrin polymers into soluble fragments. However, besides plasmin(ogen) and α₂-antiplasmin the system contains a series of specific activators and inhibitors. The main physiological activators of plasminogen are tissue-type plasminogen activator, which is mainly involved in the dissolution of the fibrin polymers by plasmin, and urokinase-type plasminogen activator, which is primarily responsible for the generation of plasmin activity in the intercellular space. Both activators are multidomain serine proteases. Besides the main physiological inhibitor α₂-antiplasmin, the plasmin–antiplasmin system is also regulated by the general protease inhibitor α₂-macroglobulin, a member of the protease inhibitor I39 family. The activity of the plasminogen activators is primarily regulated by the plasminogen activator inhibitors 1 and 2, members of the serine protease inhibitor superfamily.     

Recent observations on the structure and the properties of yeast NMN adenylyltransferase

A homogeneous preparation of yeast NMN adenylyltransferase (EC 2.7.7.1) showed microheterogeneity, which was revealed by FPLC (Fast Protein Liquid Chromatography) ion exchange chromatography. The resolved components have been characterized with respect to electrophoretic behavior and adenine content. The results led to a hypothesis about a possible role of poly(ADP-ribosylation) in modulating the enzyme activity.     

Fibrinolyse im Kammerwasser menschlicher und tierischer Augen

Summary In the aqueous humour of human subjects and of various animals species, a fibrinolytic system has been demonstrated which, as regards streptokinase, shows the same properties as the corresponding plasma. Presumably the actual fibrinolytic activity in the aqueous humour is greater than in the plasma.     

Sex related fibrinolytic activity in rat tissues

Histochemical study of many organs of male and female adult Wistar rats of the same age showed no difference in fibrinolytic activity (plasminogen activator activity) between the sexes.     

Sex related fibrinolytic activity in rat tissues

Summary Histochemical study of many organs of male and female adult Wistar rats of the same age showed no difference in fibrinolytic activity (plasminogen activator activity) between the sexes.     

Characterization and antithrombotic action of tissue plasminogen activator

An extractive fibrinolytic enzyme has been characterized and found to belong to the class of vascular plasminogen activators. The agent has been found to have an antithrombotic action in the rabbit.     

Presence of NAD pyrophosphorylase in skeletal muscle in dystrophic mice

Summary NAD pyrophosphorylase (ATP:NMN adenylyltransferase) activity has been measured in the skeletal muscle of dystrophic mice. The amount of this enzyme in the dystrophic mice, as determined by three different methods, was about one half of that in the controls. In addition, the concentration of ATP was too low to be detected in crude extracts of dystrophic mouse skeletal muscle, which were prepared using Tris buffer alone or Tris buffer containing either 3 M KCl, or 1 mM PMSF.