Gonadal and adrenal steroids were shown to affect multiple immune processes including inflammatory response. These effects were documented, specifically, through an influence on local productions of cytokines and the functions of synovial cells at the site of inflammatory processes. The aim of this study was to investigate the levels of selected hormones in synovial fluid of knee joints of patients with rheumatoid arthritis (RA) and with osteoarthrosis (OS, control group).
The concentrations of cortisol (CORT), 17-beta-estradiol (ES), dehydroepiandrosterone (DHEA), testosterone (TE), progesterone (PRG), and aldosterone (ALD) were determined in plasma and synovial fluid.
Significant positive correlations between the levels in plasma and synovial fluids were observed in hormones ES, PRG, TE, DHEA and ALD. In most hormones, the levels in synovial fluids were similar as in plasma; however, the content of ALD was higher in synovial fluid as compared to plasma. Higher levels of ES (in females), DHEA (in males), and ALD were observed in plasma and synovial fluids of RA patients as compared to OS patients. After adjustment to age, no significant RA vs. OS difference was noted in ES, TE, DHEA, PRG, and CORT in plasma and synovial fluid. Age-adjusted ALD concentration tended to be higher in synovial fluid of RA patients as compared to OS patients. The ratio of ES/TE concentrations in synovial fluid was significantly higher in male RA patients compared to OS group. Also the ES/CS and ES/DHEA ratios in synovial fluid were elevated in RA patients in comparison to controls.
These results demonstrated the prevalence of pro-inflammatory hormones in synovial fluid of RA patients, suggesting the possible role of these steroid hormones in inflammatory processes.