Mizoribine

Mizoribine is a newly developed immunosuppressive agent that has low toxicity. Mizoribine (Bredinin) exerts its activity through selective inhibition of inosine monophosphate synthetase and guanosine monophosphate synthetase, resulting in the complete inhibition of guanine nucleotide synthesis without incorporation into nucleotides. It arrests DNA synthesis in the S phase of cellular division. Mizoribine has a therapeutic role in some patients with chronic autoimmune urticaria and may be useful for treatment of cases not responsive to classical therapy. In vitro basophil histamine release assays suggested that Mizoribine might help to reduce anti-IgE autoantibody acting on the surface of basophils in chronic autoimmune urticaria. Mizoribine (MZR) reduced PAN-induced integrin-linked kinase activation (ILK) and phosphorylation of glycogen synthase kinase-3beta (GSK3beta) in vivo and in vitro. Mizoribine (MZR) directly prevents PAN-induced podocyte injury, possibly by affecting signaling cascades involving ILK and GSK3beta.