The efficacy of hirudin

Hirudin is the active ingredient secreted by leeches and leech salivary glands. This ingredient contains a variety of small molecule proteins and has a strong inhibitory effect on thrombin. It is the strongest natural specific inhibitor discovered so far. It is often used in anticoagulant and blood-dissolving drugs, and can play a good role in the treatment of various thrombotic diseases, especially for diffuse vascular coagulation and venous thrombosis, and can play a good therapeutic effect.

Effects of Hirudin

Animal experiments and clinical studies have shown that hirudin can effectively resist blood coagulation and thrombosis, and prevent further blood stasis phenomena such as thrombin-catalyzed activation of coagulation factors and platelet reactions. In addition, it inhibits thrombin-induced proliferation of fibroblasts and thrombin stimulation of endothelial cells.

Compared with heparin, it not only requires less dosage, does not cause bleeding, but also does not rely on endogenous cofactors; while heparin has the risk of causing bleeding, antithrombin III often decreases during the onset of disseminated intravascular coagulation, which will limit the efficacy of heparin. The use of leeches will have a better effect.

application

Hirudin is a very promising class of anticoagulant and blood-dissolving drugs. It can be used to treat various thrombotic diseases, especially venous thrombosis and diffuse vascular coagulation. It can also be used to prevent the formation of arterial thrombosis after surgery, prevent the formation of thrombus after thrombus dissolution or after vascular reconstruction, and improve extracorporeal blood circulation and hemodialysis processes. Microsurgery often fails due to vascular embolism at the anastomosis. The use of hirudin can promote wound healing. Studies have also shown that hirudin can play a role in tumor treatment. It can prevent the metastasis of tumor cells and has been shown to be effective in treating tumors such as fibrosarcoma, osteosarcoma, angiosarcoma, melanoma and leukemia. Hirudin can also be used in conjunction with chemotherapy and radiotherapy to enhance the efficacy by promoting blood flow in tumors.

Animal experiments and clinical studies have shown that intravenous or subcutaneous injection of hirudin has no obvious toxic side effects. Regardless of acute or subacute toxicity tests, it has no effect on blood pressure, heart rate, blood phase, bleeding time and blood chemical composition. It has no effect on the respiratory system, no allergic reactions, and generally no specific antibodies are found. The median lethal dose LD50>50mgAg, which is much larger than the dose used in treatment (1mgAg). It is particularly worth noting that hirudin can be taken orally, which greatly facilitates medication. Hirudin is relatively stable. Trypsin and chymotrypsin do not destroy its activity. Moreover, some hydrolyzed fragments of hirudin still have the ability to inhibit coagulation.

This can explain why oral leech extract from traditional Chinese medicine is still effective.

Its annual output value reaches tens of millions of yuan. New drugs containing leeches are also being researched and launched. Further clinical research is needed to use genetic engineering to produce recombinant leech polypeptide drugs to replace hirudin or as an additive to anticoagulant and blood-dissolving drugs. There is no doubt that the development of recombinant hirudin peptide drugs will bring huge social and economic benefits.