RT Journal Article SR Electronic T1 Increased Serum Levels of Nɛ-(hexanoyl)lysine, A New Marker of Oxidative Stress, in Systemic Sclerosis JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 2214 OP 2219 DO 10.3899/jrheum.080191 VO 35 IS 11 A1 KAZUHIRO SHIMIZU A1 FUMIHIDE OGAWA A1 YUICHIRO AKIYAMA A1 EIJI MUROI A1 AYUMI YOSHIZAKI A1 YOHEI IWATA A1 KAZUHIRO KOMURA A1 SANGJAE BAE A1 SHINICHI SATO] YR 2008 UL http://www.jrheum.org/content/35/11/2214.abstract AB Objective To determine serum levels of Nɛ-(hexanoyl)lysine (HEL), a new marker of oxidative stress, and its clinical association in patients with systemic sclerosis (SSc). Methods Serum HEL levels from 26 patients with limited cutaneous SSc (lSSc), 34 with diffuse cutaneous SSc (dSSc), 20 with systemic lupus erythematosus (SLE), 20 with dermatomyositis (DM), and 40 healthy individuals were examined by enzyme linked immunosorbent assay. Results Serum HEL levels were elevated in patients with SSc compared with healthy controls (n = 40) with similar levels between patients with lSSc and dSSc (p < 0.0001). SSc patients with elevated HEL levels had increased serum levels of anti-agalactosyl IgG antibody, rheumatoid factor (RF), and IgM than those with normal HEL levels (p < 0.05). HEL levels correlated positively with anti-agalactosyl IgG antibody (p = 0.013, r = 0.408) and RF titer (p = 0.0028, r = 0.426). Conclusion Our results suggest that oxidative stress may play an important role in immunological abnormalities of SSc, especially in the production of autoantibodies including anti-agalactosyl IgG antibody and RF.