Thioredoxin-1, redox factor-1 and thioredoxin-interacting protein, mRNAs are differentially expressed in Multiple Sclerosis patients exposed and non-exposed to interferon and immunosuppressive treatments.

BACKGROUND: Oxidative stress is closely linked to inflammation in neurodegenerative diseases. We aimed to investigate the expression of redox system genes in Multiple Sclerosis (MS) patients either exposed or not exposed to conventional treatments.

METHODS: Forty-four MS patients were divided into three groups: newly diagnosed (Group 1), receiving interferon (Group 2) and receiving immunosuppressive drugs (Group 3). Also, 15 healthy controls were enrolled. The mRNA expression of TRX1, TXNRD1, TRX2, TXNRD2, TXNIP, and APEX1 genes in peripheral blood mononuclear cells (PBMCs) was assessed by relative quantitative real-time PCR. Also, serum level of Trx1 was measured by ELISA.

RESULTS: Serum level of Trx1 in the newly diagnosed MS patients was significantly higher compared to the healthy controls (P=0.013). Likewise, TRX1 and APEX1 expressions were significantly higher in the newly diagnosed patients compared to controls (P=0.003 and P=0.042), patients under interferon treatment (P=0.003 and P=0.013), and patients received immunosuppressants (P=0.001 and P=0.025). Furthermore, TXNIP expression in MS patients (either group 1, group 2, or group 3) was significantly lower than that in the control group (P=0.017, P=0.002, and P=0.022 respectively). The expression of TXNRD1, TRX2, and TXNRD2 did not show any significant difference between the control and the MS patient (P>0.05).

CONCLUSIONS: Our data showed that redox system elements are differentially expressed in newly diagnosed MS patients, or patients receiving either interferon or immunosuppressive treatments. However, much more studies are required to confirm our findings and clarify the underlying mechanisms.