Patricia Restituto

Advantage of salivary cortisol measurements in the diagnosis of glucocorticoid related disorders

OBJECTIVE Salivary cortisol in the assessment of glucocorticoid related disorders. DESIGN-METHODS: Serum and salivary cortisol were measured in 189 patients (22 Cushings syndrome, 67 pseudo-Cushing, 11 Addisons disease, 89 controls) at 8:00 and 24:00 h. RESULTS Serum and salivary cortisol correlated in the whole study population (r=0.62, p=0.000). Morning serum and saliva cortisol in Addisons disease were lower than in controls (6.74+/-1.69 vs 22.58+/-1.78 microg/dL, and 0.15+/-0.25 vs 0.67+/-0.12 microg/dL) (p<0.001). Morning serum cortisol was similar in controls and patients with Cushings syndrome or pseudo-Cushing (22.58+/-1.78 vs 13.96+/-6.02 vs 16.13+/-1.69 microg/dL). Morning serum and salivary cortisol at 8:00 had the same sensitivity to distinguish patients with Addisons disease from healthy controls. 24:00 am serum cortisol in controls (2.61+/-0.20 microg/dL) was lower than in the pseudo-Cushing group (6.53+/-0.77 microg/dL, p<0.001) and in Cushings syndrome (10.90+/-2.36 microg/dL, p=0.003). 24:00 am salivary cortisol in controls (0.0025+/-0.001 microg/dL) was lower than in patients with Cushings syndrome (0.58+/-0.11 microg/dL, p<0.001) and those higher than in patient with pseudo-Cushing (0.10+/-0.06 microg/dL, p=0.001). Both salivary cortisol and serum cortisol presented high specificity (82% and 100%) to detect Cushings syndrome but salivary cortisol higher sensitivity (saliva 88% and serum 50%). CONCLUSION Morning salivary cortisol is as good as serum as screening test for patients with Addisons disease and nighttime salivary cortisol is more adequate than serum in the screening of Cushings syndrome.

The Proinflammatory Mediator CD40 Ligand Is Increased in the Metabolic Syndrome and Modulated by Adiponectin

OBJECTIVES We hypothesized that the CD40/CD40 ligand (CD40L) system is up-regulated in the metabolic syndrome (MS) and modulated by adiponectin (AN). The objectives were: 1) to compare plasma and monocyte CD40L in patients with MS and controls and its association with clinical and biochemical parameters, 2) to investigate platelets as a source of soluble CD40L (sCD40L), and 3) to analyze the effects of AN on CD40/CD40L. METHODS Plasma sCD40L and AN were measured in 246 controls and 128 patients with MS by ELISA. Monocyte CD40/CD40L expression and platelet CD40L content and release were compared in patients with MS and controls. Monocytes and endothelial cells were cultured with AN and CD40/CD40L expression determined by real-time RT-PCR and Western blotting. RESULTS Patients with MS had higher sCD40L and lower AN levels than controls (0.89 +/- 0.1 vs. 0.76 +/- 0.07 ng/ml and 10.10 +/- 0.65 vs. 12.99 +/- 0.80 microg /ml, P < 0.05). Monocyte CD40/CD40L expression was higher (P < 0.05) in patients than controls (CD40: 1.31 +/- 0.31 vs. 0.80 +/- 0.14 arbitrary units; CD40L: 1.24 +/- 0.85 vs. 0.43 +/- 0.14 pg/microg protein). No differences were observed on CD40L content between resting platelets from patients with MS and controls (7.7 +/- 3.5 vs. 7.2 +/- 2.2 pg/microg protein). Stimulated platelets from patients with the MS released more (P < 0.05) sCD40L than controls (582 +/- 141 vs. 334 +/- 60% change vs. nonstimulated platelets). AN reduced CD40L mRNA and protein expression in monocytes from MS patients and endothelial cells. CONCLUSIONS The enhanced sCD40L and cellular CD40L expression in the MS suggests that CD40L is of pathophysiological relevance in MS. Also, a new antiinflammatory effect of AN is described through the modulation of the CD40/CD40L system.

Gender Differences in Plasma Biomarker Levels in a Cohort of COPD Patients: A Pilot Study

Rationale Little is known about gender differences in plasma biomarker levels in patients with chronic obstructive pulmonary disease (COPD). Hypothesis There are differences in serum biomarker levels between women and men with COPD. Objective Explore gender differences in plasma biomarker levels in patients with COPD and smokers without COPD. Methods We measured plasma levels of IL-6, IL-8, IL-16, MCP-1, MMP-9, PARC and VEGF in 80 smokers without COPD (40 males, 40 females) and 152 stable COPD patients (76 males, 76 females) with similar airflow obstruction. We determined anthropometrics, smoking history, lung function, exercise tolerance, body composition, BODE index, co-morbidities and quality of life. We then explored associations between plasma biomarkers levels and the clinical characteristics of the patients and also with the clinical and physiological variables known to predict outcome in COPD. Results The plasma biomarkers level explored were similar in men and women without COPD. In contrast, in patients with COPD the median value in pg/mL of IL-6 (6.26 vs 8.0, p = 0.03), IL-16 (390 vs 321, p = 0.009) and VEGF (50 vs 87, p = 0.02) differed between women and men. Adjusted for smoking history, gender was independently associated with IL-16, PARC and VEGF levels. There were also gender differences in the associations between IL-6, IL-16 and VEGF and physiologic variables that predict outcomes. Conclusions In stable COPD patients with similar airflow obstruction, there are gender differences in plasma biomarker levels and in the association between biomarker levels and important clinical or physiological variables. Further studies should confirm our findings.

Circulating osteoprotegerin is increased in the metabolic syndrome and associates with subclinical atherosclerosis and coronary arterial calcification.

CONTEXT The relationship between osteoprotegerin (OPG) a glycoprotein related to bone metabolism and the metabolic syndrome (MS) has not been established. OBJECTIVE The aim of this study is to evaluate OPG concentration in patients with MS and its association with subclinical atherosclerosis and coronary arterial calcification (CAC). MATERIALS/METHODS The study included 238 asymptomatic patients. MS was diagnosed according to the NCEP/ATPIII guidelines. OPG was measured by ELISA. All subjects underwent ultrasonography of the common carotid arteries to measure intima-media thickness (IMT) and evaluate the presence of atheroma plaques. In a subgroup (n=39) CAC was quantified by ECG-triggered cardiac computed tomography. Adipose tissue was excised from 25 patients and OPG expression by RT-PCR and immunohistochemistry was studied. RESULTS Patients with the MS (n=60) had higher OPG than patients without (n=178) (p<0.05). OPG correlated with IMT (r=0.2, p=0.005) and patients with atheroma plaques had higher OPG (p=0.008) and also those with coronary artery calcification (p<0.05). OPG expression was confirmed in adipose tissue (n=12) and the expression was significantly higher in patients with MS than in those without (p=0.003). CONCLUSIONS This study shows that OPG may potentially be a biomarker for cardiovascular risk/damage in the MS and identifies adipose tissue as a potential source of OPG.

Adiponectin diminishes platelet aggregation and sCD40L release. Potential role in the metabolic syndrome

The proinflammatory and proatherogenic mediator, soluble CD40 ligand (CD40L), is increased in the metabolic syndrome (MS) and released from platelets. We hypothesized that adiponectin modulates platelet function, and we sought to evaluate the association of adiponectin and sCD40L levels with platelet aggregation in MS and the effects of adiponectin on platelet aggregation and activation. Platelet aggregation and circulating adiponectin, sCD40L and P-selectin were determined in 30 controls and 30 patients with MS. Also, in vitro studies were performed in platelet-rich plasma from nine healthy volunteers. Adiponectin receptors were demonstrated by Western blotting and flow cytometry. ADP and epinephrine platelet aggregation was measured after preincubation with adiponectin. sCD40L and P-selectin secretion was measured in the supernatants by ELISA. Patients with MS had higher sCD40L and P-selectin than controls (5.96 +/- 0.50 vs. 4.28 +/- 0.41 ng/ml, P < 0.05, and 151 +/- 8 vs. 122 +/- 9 ng/ml, P < 0.05). By contrast, adiponectin was lower in patients with MS than in controls (5.25 +/- 0.30 vs. 7.35 +/- 0.34 microg/ml, P < 0.001). Higher platelet aggregation was found in MS. Adiponectin inversely correlated with P-selectin (R = -0.35, P = 0.009), sCD40L (r = -0.24, P = 0.05) and epinephrine and collagen induced aggregation (r = -0.80, P = 0.005; r = -0.70, P = 0.011). Platelets express the receptors for adiponectin. Platelet aggregatory response to epinephrine and ADP significantly decreased following preincubation with adiponectin (96 +/- 4 vs. 23 +/- 3%, P < 0.001, and 102 +/- 9 vs. 85 +/- 9%, P = 0.004). Adiponectin prevented platelet sCD40L release (1.63 +/- 0.15 vs. 2.04 +/- 0.20 ng/ml, P < 0.001). Enhanced platelet aggregation and activation markers are found in MS associated with low adiponectin concentrations. Novel evidence is provided demonstrating that adiponectin has antithrombotic properties, since it inhibits platelet aggregation and platelet activation.

Traditional and Novel Bone Remodeling Markers in Premenopausal and Postmenopausal Women

CONTEXT Bone turnover markers (BTMs) may identify changes in bone remodeling within a relatively short time interval before changes in bone mineral density can be detected. New markers such as osteoprotegerin, receptor activator of nuclear factor-κB ligand, and sclerostin have emerged, but there is little information about their potential use in clinical practice. OBJECTIVES The aim of this study was to analyze the ability of several BTMs to predict bone loss in pre- and postmenopausal women and to monitor the efficacy of treatment in osteoporotic women. DESIGN, PATIENTS, AND SETTING We performed an observational prospective study in pre- and postmenopausal ambulatory women (n = 72 and n = 152, respectively). INTERVENTION Postmenopausal women with osteoporosis (n = 18) were treated with risedronate and calcium. Women filled out a questionnaire and underwent bone mineral density measurement using dual-energy x-ray absorptiometry at the time of enrollment and after 1 year of follow-up. BTMs were measured at baseline, at 6 months, and after 1 year. RESULTS Increased levels of N-terminal propeptide of type 1 procollagen (P1NP) and β-type I collagen telopeptides (CTXs) were associated with low bone mineral density in the premenopausal (P = .02 and P = .04, respectively) and postmenopausal (P = .03 and P = .02) groups. The best analytical performance to diagnose osteoporosis was for β-CTX, osteocalcin, and P1NP, with areas under the curve of 0.70 (P = .005), 0.64 (P = .048), and 0.71 (P = .003). A significant decrease was found in P1NP, osteocalcin, tartrate-resistant acid phosphatase-5b, β-CTX, and bone alkaline phosphatase after 1 year of treatment (all P < .05). CONCLUSIONS Our data suggest that measurement of β-CTX and P1NP shows adequate analytical performance and could potentially be included in algorithms for the screening of osteoporosis. Furthermore, these two markers, along with osteocalcin and tartrate-resistant acid phosphatase-5b, are useful to monitor the response to risedronate.