Objective: To investigate the effect of methylation modification on the mRNA expression of Cosmc gene in peripheral B lymphocytes from IgA nephropathy (IgAN).
Methods: Biopsy identified 22 cases of IgAN patients and 20 cases of normal control were included. Peripheral B lymphocytes were isolated and were cultured with RPMI1640 medium, with LPS (12.5 microg/mL) as well as demethylation agent (5-AZA 0.1 micromol/L, 0.5 micromol/ L and 1.0 micromol/L) for 72 hours, respectively. Expression level of Cosmc gene was measured using real-time PCR.
Results: The mRNA expression level of Cosmc gene in IgAN patients was significantly lower than that of control (P<0.05). The Cosmc gene expression level increased dramatically after RPMI1640 treatment (P<0.05), however, LPS could apparently reverse this effect (P<0.05). De-methylation modification up regulated the Cosmc gene expression significantly (P<0.05).
Conclusion: De-methylation modification could effectively reverse the repressed Comsc gene mRNA expression caused by external suppressors.