Increased levels of HSPA5 in the serum of patients with inflammatory myopathies--preliminary findings.
Endoplasmic reticulum (ER) stress is suggested to play an important role in the pathogenesis of myositis recently. The aim of this study was to investigate the serum concentration of an ER stress-specific chaperone protein HSPA5 in patients with inflammatory myopathies. Forty-five patients (27 with polymyositis (PM) and 18 with dermatomyositis (DM)) were included in the study, and all received prednisone therapy. Serum samples were collected from each patient before and after prednisone treatment. Serum HSPA5 levels were detected by enzyme-linked immunosorbent assays. The serum level of HSPA5 was significantly higher in myositis patients than in controls. In addition, the concentrations in the DM subgroup were significantly higher than in the PM groups. Serum HSPA5 levels were positively correlated with creatine kinase (CK) and C-reactive protein (CRP) in PM patients. In patients with DM, the serum HSPA5 concentrations were also found significantly correlated with CK, but not with CRP. After prednisone treatment, serum HSPA5 levels significantly decreased compared to baseline in steroid responders, but no marked decrease was observed in steroid non-responders. Serum HSPA5 is increased in patients with DM and PM. Increased concentrations of HSPA5 in serum may reflect the enhanced ER stress in muscle tissue. Decrease in serum HSPA5 levels appears in patients with clinical remission; therefore, HSPA5 may be a potential biomarker for inflammatory myopathies.
Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1st You Yi Road, Chongqing, 400016, China.
Fei
F
Xiao
Jia-Ze
JZ
Tan
Xiao-Yan
XY
Xu
Xue-Feng
XF
Wang
D000328:Adult; D000368:Aged; D003402:Creatine Kinase / Q000378:metabolism; D003882:Dermatomyositis / Q000097:blood*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005938:Glucocorticoids / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000097:blood* / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009220:Myositis / Q000097:blood*; D017285:Polymyositis / Q000097:blood*; D011241:Prednisone / Q000627:therapeutic use; D016896:Treatment Outcome
D000091342:Endoplasmic Reticulum Chaperone BiP; D005938:Glucocorticoids; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D003402:Creatine Kinase; D011241:Prednisone