Correlation between two biomarkers of atherosclerosis, osteopontin and angiopoietin-2, in non-diabetic ankylosing spondylitis patients undergoing TNF-α antagonist therapy.

OBJECTIVES: To determine whether circulating osteopontin (OPN) levels in patients with ankylosing spondylitis (AS) undergoing TNF-α antagonist-infliximab-therapy are increased compared with controls and to establish whether disease activity, systemic inflammation, metabolic syndrome, adipokines and biomarkers of atherosclerosis are potential determinants of circulating OPN levels in these patients. METHODS: We assessed OPN serum concentrations in a series of 30 non-diabetic AS patients without cardiovascular disease undergoing TNF-α antagonist-infliximab therapy and 48 matched controls. OPN levels were measured immediately before and after an infliximab infusion, at time 0 and at time 120 minutes respectively. Correlations of OPN serum levels with clinical features, disease activity, systemic inflammation, metabolic syndrome and several biomarkers of atherosclerosis were assessed. Potential changes in OPN concentration following an infusion of anti-TNF-α monoclonal antibody-infliximab were also analysed. RESULTS: At the time of the study AS patients undergoing anti-TNF-α therapy had low disease activity (mean BASDAI 2.94) and they showed similar OPN serum levels to healthy controls. No differences in OPN levels according to the specific clinical features of the disease were seen. Also, no correlation between OPN concentration and insulin resistance and adipokines was observed. However, a positive correlation between OPN and angiopoietin-2 (Angpt-2) serum levels was found (r=0.397; p=0.04). In addition, a single infliximab infusion led to a marginal statistically significant reduction in OPN levels (24112.19±14608.73 pg/ml at time 0 versus 21806.62±11390.83 pg/ml at time 120'; p=0.05). CONCLUSIONS: OPN and Angpt-2 serum levels are correlated in non-diabetic AS patients undergoing TNF-α antagonist therapy.

Influence of sodium valproate on late follicular phase pulsatile LH secretion in normal women.

OBJECTIVE: To study whether modulation of the GABAergic system (with sodium valproate) affects pulsatile LH secretion in the late follicular phase of normal women. DESIGN: Fifteen normal women volunteers were studied over an 8-hour period in the late follicular phase of two successive menstrual cycles. On each occasion, blood samples were taken every 10 minutes between 1000 and 1800 h. Nine of the volunteers--the short treatment group--were administered 400 mg of sodium valproate every 8 hours on the two days preceding their second session, and a further 400 mg at 0900 h on the day of the session. The other six--the long treatment group--were administered 400 mg of sodium valproate every 8 hours on the seven days preceding their second session and at 0900 and 1400 h on the day of the session. MEASUREMENTS: LH, oestradiol and progesterone were determined by radioimmunoassay, and sodium valproate by repolarization fluorescence spectrophotometry. Pulse detection was carried out both by the program ULTRA and by a method developed by the authors. RESULTS: There were no significant differences in LH pulse amplitude or relative pulse amplitude between records taken in the first and second menstrual cycles, i.e. without or with prior sodium valproate treatment. Short treatment did change interpulse interval and mean secretion period, but the changes, though statistically significant, were small (about 10 minutes), so that the values for both post-treatment and control sessions were within the normal range; these parameters were unaffected by long treatment. CONCLUSIONS: Activation of the GABAergic system with sodium valproate had no biologically significant effect on the late follicular phase pulsatile LH secretion of these normal women.