Clinical data | |
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Other names | SK |
AHFS/Drugs.com | Micromedex Detailed Consumer Information |
Routes of administration | Intravenous |
ATC code | |
Identifiers | |
CAS Number | |
DrugBank | |
ChemSpider |
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UNII | |
ECHA InfoCard | 100.029.667 |
Chemical and physical data | |
Formula | C2100H3278N566O669S4 |
Molar mass | 47286.86 g·mol−1 |
Streptokinase is a thrombolytic medication activating plasminogen by nonenzymatic mechanism. [1] As a medication it is used to break down clots in some cases of myocardial infarction (heart attack), pulmonary embolism, and arterial thromboembolism. [2] The type of heart attack it is used in is an ST elevation myocardial infarction (STEMI). [3] It is given by injection into a vein. [2]
Side effects include nausea, bleeding, low blood pressure, and allergic reactions. [2] A second use in a person's lifetime is not recommended. [2] While no harm has been found with use in pregnancy, it has not been well studied in this group. [4] Streptokinase is in the antithrombotic family of medications and works by turning on the fibrinolytic system. [3]
Streptokinase was discovered in 1933 from beta-hemolytic streptococci. [5] It is on the World Health Organization's List of Essential Medicines. [6] It is no longer commercially available in the United States. [7]
If percutaneous coronary intervention (PCI) is not available within 90–120 minutes of first contact, streptokinase is recommended intravenously as soon as possible after the onset of a ST elevation myocardial infarction (STEMI). As streptokinase is a bacterial product, the body has the ability to build up an immunity to it. Therefore, it is recommended that this medication should not be used again after four days from the first administration, as it may not be as effective and can also cause an allergic reaction. For this reason, it is usually given only for a person's first heart attack. Further thrombotic events could be treated with tissue plasminogen activator (tPA). Overdose of streptokinase or tPA can be treated with aminocaproic acid.
Streptokinase C | |||||||
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Identifiers | |||||||
Organism | |||||||
Symbol | skc | ||||||
Entrez | 8110746 | ||||||
PDB | 1BML | ||||||
UniProt | P00779 | ||||||
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Staphylokinase/Streptokinase family | |||||||||||
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Identifiers | |||||||||||
Symbol | Staphylokinase | ||||||||||
Pfam | PF02821 | ||||||||||
InterPro | IPR004093 | ||||||||||
SCOP2 | 2sak / SCOPe / SUPFAM | ||||||||||
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Streptokinase belongs to a group of medications known as fibrinolytics, and complexes of streptokinase with human plasminogen can hydrolytically activate other unbound plasminogen by activating through bond cleavage to produce plasmin. There are three domains to streptokinase, denoted α (residues 1–150), β (residues 151–287), and γ (residues 288–414). Each domain binds plasminogen, although none can activate plasminogen independently. [10]
Plasmin is produced in the blood to break down fibrin, the major constituent of blood thrombi, thereby dissolving clots once they have fulfilled their purpose of stopping bleeding. Extra production of plasmin caused by streptokinase breaks down unwanted blood clots, for example, in the lungs (pulmonary embolism). The usual activation of plasminogen is by proteolysis of the Arg561—Val562 bond. [11] The amino group of Val562 then forms a salt-bridge with Asp740, which triggers a conformational change producing the active protease plasmin. When streptokinase is present, it binds to plasminogen to form a complex (streptokinase·plasminogen) that converts substrate plasminogen to plasmin. Residues 1–59 of streptokinase regulate its capacity to induce an active site in bound plasminogen by a nonproteolytic mechanism and to activate substrate plasminogen in a fibrin-independent manner. This complex subsequently rearranges to an active complex although the Arg561–Val562 bond remains intact. Therefore, another residue must substitute for the free amino group of Val562 and provide a counterion for Asp740 in this active complex. [12] Two candidates for this counterion have been suggested: Ile1 of streptokinase and Lys698 of plasminogen. Deletion of Ile1 of streptokinase markedly inhibits its capacity to induce an active site in plasminogen, which supports the hypothesis that establishment of a salt bridge between Ile1 of streptokinase and Asp740 of plasminogen is necessary for streptokinase to induce an active site in plasminogen by a nonproteolytic mechanism. [13] In contrast with the Ile1 substitutions, the Lys698 mutations also decreased the dissociation constant of the streptokinase complex by 15 to 50 fold. These observations suggest that Lys698 is involved in formation of the initial streptokinase·plasminogen complex. [14]
Streptokinase is naturally produced by Streptococci spp. bacteria, which use this enzyme to break up blood clots so that they can spread from the initial site of infection. It can also activate fibrin. [15]
It is similar, both in function and in structure, to staphylokinase (Sak) found in Staphylococcus aureus. Staphylokinase is considered a virulence factor, [16] although its presence after the establishment of infection actually decreases disease severity. Both enzymes are carried by phages. [17]
After many years of work along with his student Sol Sherry, William S. Tillett discovered streptokinase in 1933. Initially used in treatment of fibrinous pleural exudates, hemothorax and tuberculous meningitis, its role in acute myocardial infarction was serendipitous. [5]
Streptokinase may find a use in helping to prevent postoperative adhesions, a common complication of surgery, especially abdominal surgery (appendectomy, gall stones, hysterectomy, etc.) One study using animal models (rats) found that when used with a PHBV membrane drug-delivery system, it was 90 percent effective in preventing adhesions. [18] However, it has not been shown to be effective in humans in a clinical trial.
It is marketed in Chile as Streptase by Alpes Selection, under license of CSL Behring Germany.
Available in Vietnam under the name Mutose. Available in Cuba, Venezuela, Ecuador and other Latin American countries under the trademark Heberkinasa, commercialized by Heber Biotech, Havana, Cuba. Available in India under the name STPase by Cadila Pharmaceuticals, and Myokinase by Biocon Limited.
A thrombus, colloquially called a blood clot, is the final product of the blood coagulation step in hemostasis. There are two components to a thrombus: aggregated platelets and red blood cells that form a plug, and a mesh of cross-linked fibrin protein. The substance making up a thrombus is sometimes called cruor. A thrombus is a healthy response to injury intended to stop and prevent further bleeding, but can be harmful in thrombosis, when a clot obstructs blood flow through healthy blood vessels in the circulatory system.
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism of coagulation involves activation, adhesion and aggregation of platelets, as well as deposition and maturation of fibrin.
Disseminated intravascular coagulation (DIC) is a condition in which blood clots form throughout the body, blocking small blood vessels. Symptoms may include chest pain, shortness of breath, leg pain, problems speaking, or problems moving parts of the body. As clotting factors and platelets are used up, bleeding may occur. This may include blood in the urine, blood in the stool, or bleeding into the skin. Complications may include organ failure.
Fibrinogen is a glycoprotein complex, produced in the liver, that circulates in the blood of all vertebrates. During tissue and vascular injury, it is converted enzymatically by thrombin to fibrin and then to a fibrin-based blood clot. Fibrin clots function primarily to occlude blood vessels to stop bleeding. Fibrin also binds and reduces the activity of thrombin. This activity, sometimes referred to as antithrombin I, limits clotting. Fibrin also mediates blood platelet and endothelial cell spreading, tissue fibroblast proliferation, capillary tube formation, and angiogenesis and thereby promotes revascularization and wound healing.
Thrombin is a serine protease, an enzyme that, in humans, is encoded by the F2 gene. Prothrombin is proteolytically cleaved to form thrombin in the clotting process. Thrombin in turn acts as a serine protease that converts soluble fibrinogen into insoluble strands of fibrin, as well as catalyzing many other coagulation-related reactions.
Fibrinolysis is a process that prevents blood clots from growing and becoming problematic. Primary fibrinolysis is a normal body process, while secondary fibrinolysis is the breakdown of clots due to a medicine, a medical disorder, or some other cause.
Thrombolysis, also called fibrinolytic therapy, is the breakdown (lysis) of blood clots formed in blood vessels, using medication. It is used in ST elevation myocardial infarction, stroke, and in cases of severe venous thromboembolism.
Tissue-type plasminogen activator, short name tPA, is a protein involved in the breakdown of blood clots. It is encoded in the human by the PLAT gene. It is a serine protease found on endothelial cells, the cells that line the blood vessels. As an enzyme, it catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for clot breakdown. Human tPA has a molecular weight of ~70 kDa in the single-chain form.
Plasmin is an important enzyme present in blood that degrades many blood plasma proteins, including fibrin clots. The degradation of fibrin is termed fibrinolysis. In humans, the plasmin protein is encoded by the PLG gene.
Urokinase, also known as urokinase-type plasminogen activator (uPA), is a serine protease present in humans and other animals. The human urokinase protein was discovered, but not named, by McFarlane and Pilling in 1947. Urokinase was originally isolated from human urine, and it is also present in the blood and in the extracellular matrix of many tissues. The primary physiological substrate of this enzyme is plasminogen, which is an inactive form (zymogen) of the serine protease plasmin. Activation of plasmin triggers a proteolytic cascade that, depending on the physiological environment, participates in thrombolysis or extracellular matrix degradation. This cascade had been involved in vascular diseases and cancer progression.
Alteplase, sold under the brand name Activase among others, is a biosynthetic form of human tissue-type plasminogen activator (t-PA). It is a thrombolytic medication used to treat acute ischemic stroke, acute ST-elevation myocardial infarction, pulmonary embolism associated with low blood pressure, and blocked central venous catheter. It is given by injection into a vein or artery. Alteplase is the same as the normal human plasminogen activator produced in vascular endothelial cells and is synthesized via recombinant DNA technology in Chinese hamster ovary cells (CHO). Alteplase causes the breakdown of a clot by inducing fibrinolysis.
Factor XIII or fibrin stabilizing factor is a zymogen found in blood of humans and some other animals. It is activated by thrombin to factor XIIIa. Factor XIIIa is an enzyme of the blood coagulation system that crosslinks fibrin. Deficiency of XIII worsens clot stability and increases bleeding tendency.
Plasminogen activators are serine proteases that catalyze the activation of plasmin via proteolytic cleavage of its zymogen form plasminogen. Plasmin is an important factor in fibrinolysis, the breakdown of fibrin polymers formed during blood clotting. There are two main plasminogen activators: urokinase (uPA) and tissue plasminogen activator (tPA). Tissue plasminogen activators are used to treat medical conditions related to blood clotting including embolic or thrombotic stroke, myocardial infarction, and pulmonary embolism.
Anistreplase is a thrombolytic drug. It is also known as anisoylated plasminogen streptokinase activator complex (APSAC). As a thrombolytic drug, it is used to treat blood clots in emergency situations.
Tenecteplase, sold under the trade names TNKase, Metalyse and Elaxim, is an enzyme used as a thrombolytic drug.
Désiré, Baron Collen is a Belgian physician, chemist, biotechnology entrepreneur and life science investor. He made several discoveries in thrombosis, haemostasis and vascular biology in many of which serendipity played a significant role. His main achievement has been his role in the development of tissue-type plasminogen activator (t-PA) from a laboratory concept to a life-saving drug for dissolving blood clots causing acute myocardial infarction or acute ischemic stroke. Recombinant t-PA was produced and marketed by Genentech Inc as Activase and by Boehringer Ingelheim GmbH as Actilyse, and is considered biotechnology's first life saving drug.
Staphylokinase is a protein produced by Staphylococcus aureus. It contains 136 amino acid residues and has a molecular mass of 15kDa. Synthesis of staphylokinase occurs in late exponential phase. It is similar to streptokinase.
The fibrinolysis system is responsible for removing blood clots. Hyperfibrinolysis describes a situation with markedly enhanced fibrinolytic activity, resulting in increased, sometimes catastrophic bleeding. Hyperfibrinolysis can be caused by acquired or congenital reasons. Among the congenital conditions for hyperfibrinolysis, deficiency of alpha-2-antiplasmin or plasminogen activator inhibitor type 1 (PAI-1) are very rare. The affected individuals show a hemophilia-like bleeding phenotype. Acquired hyperfibrinolysis is found in liver disease, in patients with severe trauma, during major surgical procedures, and other conditions. A special situation with temporarily enhanced fibrinolysis is thrombolytic therapy with drugs which activate plasminogen, e.g. for use in acute ischemic events or in patients with stroke. In patients with severe trauma, hyperfibrinolysis is associated with poor outcome. Moreover, hyperfibrinolysis may be associated with blood brain barrier impairment, a plasmin-dependent effect due to an increased generation of bradykinin.
Reperfusion therapy is a medical treatment to restore blood flow, either through or around, blocked arteries, typically after a heart attack. Reperfusion therapy includes drugs and surgery. The drugs are thrombolytics and fibrinolytics used in a process called thrombolysis. Surgeries performed may be minimally-invasive endovascular procedures such as a percutaneous coronary intervention (PCI), which involves coronary angioplasty. The angioplasty uses the insertion of a balloon and/or stents to open up the artery. Other surgeries performed are the more invasive bypass surgeries that graft arteries around blockages.
Darexaban (YM150) is a direct inhibitor of factor Xa created by Astellas Pharma. It is an experimental drug that acts as an anticoagulant and antithrombotic to prevent venous thromboembolism after a major orthopaedic surgery, stroke in patients with atrial fibrillation and possibly ischemic events in acute coronary syndrome. It is used in form of the maleate. The development of darexaban was discontinued in September 2011.