Effects of pulse methylprednisolone and oral methylprednisolone treatments on serum levels of oxidative stress markers in Graves' ophthalmopathy

Abstract

Background: Recent evidence has shown that oxidative stress may play a role in the pathogenesis of autoimmune diseases, and this is an issue of considerable research interest in the field of infiltrative ophthalmopathy. Therefore, we evaluated both the relationship between Graves' ophthalmopathy (GO) and serum levels of certain indicators of oxidative stress, and the effects of methylprednisolone treatment on serum malondialdehyde (MDA) and glutathione (GSH) levels in patients with euthyroid GO.

Materials and methods: We compared GO patients to both Graves' patients without ophthalmopathy and healthy controls. Ultimately, we assessed four subject groups. Graves' patients with ophthalmopathy (GO) were subcategorized into two groups: Group A subjects (n = 18) were given intravenous glucocorticoid and Group B patients (n = 15) were given oral glucocorticoid. Graves' patients without ophthalmopathy comprised Group C (n = 20), and healthy controls comprised Group D (n = 15). Serum levels of MDA and GSH were measured at baseline and after 4 and 24 weeks of observation via spectrophotometric methods.

Results: We found that serum MDA levels were significantly higher in the two GO groups (Groups A and B) than in GO patients without ophthalmopathy or healthy controls. Conversely, GSH levels were significantly lower in the two GO groups than in Groups C and D. MDA and GSH levels were not different between the latter two groups. MDA levels were strongly and positively correlated with a clinical activity score (CAS). In Group A, MDA levels and the CAS were significantly lower than in Group B at 4 weeks. After 24 weeks, however, MDA levels and the CAS were similar in these two groups.

Conclusion: Oxidative stress appears to be involved in the pathophysiology of GO. Relative to oral dosing, the intravenous administration of a glucocorticoid seems to yield more rapid improvement in disease activity. MDA might be useful as an indicator of clinical activity.