Patients with Osteoarthritis and Kashin-Beck Disease Display Distinct CpG Methylation Profiles in the DIO2, GPX3, and TXRND1 Promoter Regions

Objective We aimed to analyze deoxycytidine-deoxyguanosine dinucleotide (CpGs) methylation profiles in DIO2, GPX3, and TXNRD1 promoter regions in osteoarthritis (OA) and Kashin-Beck disease (KBD) patients. Methods Blood samples were collected from 16 primary OA patients and corresponding 16 healthy individuals and analyzed for methylations in the CpGs of DIO2, GPX3, and TXNRD1 promoter regions using MALDI-TOF-MS. The methylation profiles of these regions were then compared between OA and KBD patients. Results DIO2-1_CpG_2 and DIO2-1_CpG_3 methylations were significantly lower in OA than KBD patients (P < 0.05). A similar trend was observed for GPX3-1_CpG_4, GPX3-1_CpG_7, GPX3-1_CpG_8.9.10, GPX3-1_CpG_13.14.15 and GPX3-1_CpG_16 (P < 0.05) as well as TXNRD1-1_CpG_1 and TXNRD1-1_CpG_2 methylation between OA and KBD patients (P < 0.05). However, there was no difference in methylation levels of other CpGs between the 2 groups (P > 0.05). Conclusion OA and KBD patients display distinct methylation profiles in the CpG sites of DIO2, GPX3, and TXNRD1 promoter regions. These findings provide a strong background and new perspective for future studies on mechanisms underlying epigenetic regulation of selenoprotein genes associated with OA and KBD diseases.