PT - JOURNAL ARTICLE AU - KAZUHIRO SHIMIZU AU - FUMIHIDE OGAWA AU - YUICHIRO AKIYAMA AU - EIJI MUROI AU - AYUMI YOSHIZAKI AU - YOHEI IWATA AU - KAZUHIRO KOMURA AU - SANGJAE BAE AU - SHINICHI SATO] TI - Increased Serum Levels of N<sup>ɛ</sup>-(hexanoyl)lysine, A New Marker of Oxidative Stress, in Systemic Sclerosis AID - 10.3899/jrheum.080191 DP - 2008 Nov 01 TA - The Journal of Rheumatology PG - 2214--2219 VI - 35 IP - 11 4099 - http://www.jrheum.org/content/35/11/2214.short 4100 - http://www.jrheum.org/content/35/11/2214.full SO - J Rheumatol2008 Nov 01; 35 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 &lt; 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 &lt; 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.