Serum Levels Of Leptin In Patients With Systemic Lupus Erythematosus: Correlated With Lupus Activity

To investigate the serum levels of leptin and soluble leptin receptor (sLR) in patients with systemic lupus erythematosus (SLE) and to analyze relationship between their levels and SLE disease activity. ELISA was used to measure the serum levels of leptin, sLR, and B cell activating factor ( BAFF) in forty-five patients with SLE (active, n = 23; inactive, n = 22) compared with fifteen normal controls. The relationship between serum levels of leptin, sLR and serum BAFF level, metabolism indexes as wen as SLE Disease Activity Index (SLEDAI) was evaluated by linear correlation analysis. The serum level of leptin was significantly higher in SLE patients than in normal controls, significantly higher in active SLE patients than in inactive patients, and remarkably higher in untreated SLE patients than in treated patients. It was negatively correlated with serum levels of fasting glucose, triglyceride, leukocyte counts, platelet counts, IgA, and IgM, but positively correlated with serum C4 level and 24 hours proteinuria. The serum level of sLR was significantly higher in SLE patients than in normal controls. It was positively correlated with serum levels of fasting glucose, triglyceride and IgA, but negatively correlated with serum C4. The serum leptin level was positively correlated with the serum BAFF level and negatively correlated with the serum sLR level. We conclude that the serum levels of leptin and sLR are significantly higher in SLE patients. The serum leptin level is correlated with lupus activity indexes, and it may regarded as an index of lupus activity.