Daily variability in serum endothelial NO-synthase (NOS3) levels in women with rheumatoid arthritis: association with disease course

Заічко К.О., Станіславчук М.А.

Summary. Rheumatoid arthritis (RA) is one of the most important causes of poor health and persistent disability in different countries. The leading pathogenetic link of destructive changes in the joints in RA is angiogenesis, one of the modulators of which is endothelial NO-synthase (NOS3). Linking the circadian rhythms of NOS3 products with the course of the disease will allow the personification of diagnostic and treatment measures in RA patients. Aim: to study the daily variability of serum NOS3 levels in women with RA and to evaluate the association with the course of the disease. Materials and methods. 173 patients with RA (100% female) aged 43.7±7.35 years and 34 female of the control groups aged 42.4±10.5 years were enrolled in the study. The diagnosis of RA was established by ACR/EULAR criteria 2010. Serum NOS3 level was determined at 08:00 and 20:00 by Cloud-Clone Corp. The study was conducted in compliance with bioethical standards. Statistical processing of the results was performed in the SPSS22 application package. Results. In patients with RA, in compa­rison to the healthy subjects, serum NOS3 levels were lower at 08:00 and 20:00. The decrease in morning and evening NOS3 production in RA patients is associated with an increase in the radiological stage of the disease and functional disorders; a relationship was established between the level of NOS3 in serum, the X-ray stage and indicators of disease activity and functional ability of patients (DAS28, CDAI, RAID, HAQ). Conclusions. In patients with RA, lower serum NOS3 levels were found in the morning and evening than in healthy subjects. The decrease in NOS3 morning production in RA patients is a predictor of the severity of the disease.