Regulation of IL2 and NUCB1 in Mononuclear Cells Treated With Acyl Glucuronide of Mycophenolic Acid Reveals Effects Independent of Inosine Monophosphate Dehydrogenase Inhibition

Abstract

The aim of the present study was to investigate whether the acyl glucuronide of mycophenolic acid (AcMPAG) directly affects gene expression independent of guanosine (G) depletion. Human native mononuclear cells from healthy volunteers were studied. A concentration of 100 micromol/L (50 mg/L) AcMPAG, which provided effective inhibition of cell proliferation according to dose-response curves, was selected for gene expression analysis on microarray, verified by quantitative real-time polymerase chain reaction on the LightCycler. Differentially regulated genes on the microarray were 114 inosine monophosphate dehydrogenase-independent genes involved in cell proliferation, signal transduction, chemokine stimulation, endocytosis, vesicle transport, cell adhesion, and cytoskeleton. For verification, 16 genes, which were directly or indirectly related to cell proliferation, were selected for quantitative real-time polymerase chain reaction. SCNM1, ANP32E, CXCL13, CALM1, DKFZp451J0118, TPM3, CDC42, YWHAE, CXCL3, RDX, NDUFA3, and SOD1 showed no significant difference between the studied groups (P > 0.05). CCL1 gene expression was significantly regulated (P < 0.05) only in the mononuclear cell group treated with AcMPAG, whereas YWHAZ gene expression was significantly regulated only in the group treated with AcMPAG in presence of G and 8-aminoguanosine. The difference of interleukin 2 (IL2) and nucleobindin 1 (NUCB1) expression was significant between control and AcMPAG (P < 0.05) however not significant between AcMPAG in presence and absence of G and 8-aminoguanosine (P > 0.05). The expression of interleukin 2 and nucleobindin 1 revealed an effect of AcMPAG on gene expression independent of inosine monophosphate dehydrogenase inhibition.