Reduction of oxidative stress marker levels by anti-TNF-alpha antibody, infliximab, in patients with rheumatoid arthritis.

OBJECTIVE: The aim of this study was to evaluate the effects of anti-TNF-alpha antibody, infliximab, on oxidative stress markers representing DNA damage, lipid peroxidation, and glycoxidation. METHODS: Twenty-three RA patients underwent infliximab treatment and were analyzed for 30 weeks. Six patients who experienced side effects and one patient who had a reduced efficacy of infliximab were discontinued the infliximab treatment at 30-54 weeks. Sixteen patients were analyzed for 54 weeks. The levels of serum total, urinary total, and free pentosidine, which is an advanced glycation end-product (AGE), and of urinary 15-Isoprostane F2t and 8-hydroxy-deoxy guanosine (8-OHdG) were determined at baseline and at 14, 30, and 54 weeks after initial treatment with infliximab. RESULTS: Serum total, urinary total, and free pentosidine levels were reduced at 54 weeks after initial infliximab treatment. Urinary 15-Isoprostane F2t and 8-OHdG levels were also reduced at 14, 30, and 54 weeks. Urinary 8-OHdG levels in RA patients correlated with CRP and the Disease Activity Score of 28 joints. CONCLUSION: In RA patients, infliximab plays an essential role as an anti-oxidative agent against AGE formation, oxidative DNA damage and lipid peroxydation.

The effect of infliximab on bone metabolism markers in patients with rheumatoid arthritis.

OBJECTIVE: The aim of this study was to evaluate urinary excretion of N-telopeptide of type I collagen (NTX) and deoxypyridinoline (DPD), markers of bone resorption, and serum bone alkaline phosphatase (BAP) level, a marker of bone formation and an early marker of osteoblast differentiation, in patients with rheumatoid arthritis (RA) treated with infliximab. METHODS: Seventeen male and female patients (age 60.7+/-2.53 yr; mean disease duration 12.9+/-3.01 yr; Steinbrocker's class II-IV) with RA, diagnosed according to the criteria of the American College of Rheumatology (ACR), took part in the study between March 2003 and January 2005. None of the patients had a history of oestrogen replacement therapy. All patients were treated with infliximab combined with methotrexate. Infliximab was infused intravenously at 3 mg/kg at baseline, 2 and 6 weeks, then every 8 weeks. To evaluate disease activity, ESR, CRP, the numbers of swollen and tender joints, modified Stanford Health Assessment Questionnaire (mHAQ) score and ACR score were measured. Levels of NTX and DPD in urine and BAP in serum were measured in all patients. RESULTS: ESR, CRP, the number of swollen joints and tender joints, and mHAQ score had decreased significantly 6 weeks after initial treatment and were still low 6 months after initial treatment. NTX levels had decreased significantly 6 weeks after the initial treatment and were still low 6 months after initial treatment. DPD levels had decreased 6 months after initial infusion. Mean serum BAP level did not differ significantly among the three time points. NTX levels were statistically corresponding with the number of swollen joints and mHAQ scores. DPD levels were statistically lower corresponding with ESR. CONCLUSION: Infliximab therapy may inhibit generalized bone loss in patients with RA. NTX is a more sensitive marker than DPD.

Soft x-ray absorption spectra of ilmenite family.

We have carried out soft x-ray absorption spectroscopy to study the electronic structure of ilmenite family, such as MnTiO3, FeTiO3, and CoTiO3 at the soft x-ray beamline, BL23SU, at the SPring-8. The Ti and M L2,3 absorption spectra of MTiO3 (M=Mn, Fe, and Co) show spectra of Ti4+ and M2+ electron configurations, respectively. Except the Fe L2,3 spectrum, those spectra were understood within the O(h) symmetry around the transition metal ions. The Fe L3-edge spectrum clearly shows a doublet peak at the L3 edge, which is attributed to Fe2+ state, moreover the very high-resolution the L-edge spectra of transition metals show fine structures. The spectra of those ilmenites are compared.