tcsc1823 Mizoribine

Mizoribine(NSC 289637; HE 69; β-Bredinin) is an immunosuppressive agents (IC50=100 uM) that inhibit the proliferation of lymphocytes selectively, via inhibition of IMPDH.

IC50 Value:

Target: IMPDH

in vitro: Unlike azathioprine, Mizoribine is not taken up by nucleic acids in the cell. Instead, after phosphorylation MZR-5 -monophosphate inhibits GMP synthesis by the antagonistic blocking of IMPDH (Ki = 10(-8)M) and GMP- synthetase (Ki =10(-5) M) [1]. Pretreatment of cells with MZR partially, but significantly, attenuates the expression of monocyte chemoattractant protein (MCP)-1 mRNA and protein, whereas the poly IC-induced expressions for the other functional molecules, such as CCL5, fractalkine and IL-8 were not influenced by MZR treatment [2].

in vivo:MZR 150 mg was administered once a day. After 6 months, the remission rate was 72.7% (2 subjects achieved complete remission, and 9 partial remission). After 3 and 6 months, significant reductions (p < 0.01) were obtained in 24-h proteinuria (g/day) [3].