Cyclosporin-A

Source : Beauveria Nlyea. Cyclosporin is a cyclic polypeptide immunosuppressant agent consisting of 11 amino acids and having a molecular weight of 1202.64. It is produced as a metabolite by the fungus species Beauveria nlyea. Chemically, cyclosporin is designated as [R-[R*, R*- (E) ]]-cyclic (L-alanyl-D- alanyl-N-methyl-L-leucyl-N-methyl-L-leucyl-N-methyl-L-valyl-3-hydroxy-N, 4-dimethyl-L-2-amino-6-octenoyl-L-a-amino-butyryl- N-methylglycyl-N- methyl-L-leucyl-L-valyl-N-methyl-L-leucyl) . Molecular Formula: C62H111N11O12. Cyclosporin A is a noncytotoxic, natural, 11 amino acid cyclic peptide used clinically as an immunosuppressant for the treatment of autoimmune and inflammatory disorders and to prevent organ rejection after transplantation. Cyclosporin acts chiefly by inhibiting T lymphocyte function, which is vital for the propagation of inflammation. Cyclosporin A does not suppress the activity of other hematopoietic cells, does not cause bone marrow suppression and has a rapid onset of action as opposed to other immunosuppressive agents. Nevertheless, Cyclosporin A -induced nephrotoxicity remains an important clinical problem, and oxidative stress has been implicated as a potential responsible mechanism.