Pharmacogenetics of azathioprine in inflammatory bowel disease: A role for glutathione-S-transferase?

Figure 1 Metabolism of azathioprine and mercaptopurine. 6-Me-TIMP: 6-methyl-thioinosine-monophosphate; 6-Me-TITP: 6-methyl-thioinosine-triphosphate; 6-MMP: 6-methyl-mercaptopurine; 6-MP: Mercaptopurine; 6-TGDP: 6-thioguanine-diphosphate; 6-TGMP: 6-thioguanine-monophopsphate; 6-TGN: 6-thioguanine nucleotide; 6-TGTP: 6-thioguanine-triphopshate; 6-TIMP: 6-thioinosine-monophosphate; 6-TITP: 6-thioinosine-triphosphate; 6-TU: 6-thiouric; 6-TXMP: 6-thioxanthosine-monophosphate; AZA: Azathioprine; GMPS: Guanosine-monophosphate-synthase; GST: glutathione-S-transferase; HPRT: Hypoxanthinephosphate-rybosil-transferase; IMPDH: Inosine-monophosphate-dehydrogenase; k: Kinase; TPMT: Thiopurine-S-methyl-transferase; XO: Xanthine-oxidase.

Figure 2 Schematic representation of different glutathione-S-transferase catalyzed phenomenons (blue boxes) that even through intermediate events (light blue) bring or contibute to the canonical mechanisms of action (yellow), determining the therapeutic effects (green) and/or adverse events (orange). GSH: Reduced glutathione.