Discovery and development of direct thrombin inhibitors the binding site for the globular amino-terminal domain and exosite 1 is the binding site for the acidic carboxy-terminal domain of hirudin. Native hirudin, a 65-amino-acid polypeptide, is produced in the parapharyngeal glands of medicinal leeches. Hirudins today are produced by recombinant biotechnology using yeast. These recombinant hirudins lack a sulfate group at Tyr-63 and are therefore called desulfatohirudins. They have a 10-fold lower binding affinity to thrombin compared to native hirudin, but remain a highly specific inhibitor of thrombin and have an inhibition constant for thrombin in the picomolar range. Renal clearance and degradation account for the most part
Copper peptide GHK-Cu Copper peptide GHK-Cu Copper peptide GHK-Cu is a naturally occurring copper complex of the tripeptide glycyl--histidyl--lysine. The tripeptide has strong affinity for copper(II) and was first isolated from human plasma. It can be found also in saliva and urine. Several copper(II)-peptide complexes occur naturally. In human plasma, the level of GHK-Cu is about 200 µg/ml at age 20. By the age of 60, the level drops to 80 µg/ml. In humans, GHK-Cu is proposed to promote wound healing, attraction of immune cells, antioxidant and anti-inflammatory effects, stimulation of collagen and glycosaminoglycan synthesis in skin fibroblasts and promotion of blood vessels