Protein Z-dependent protease inhibitor and protein Z in peripheral arterial disease patients

SUMMARY INTRODUCTION

Protein Z is a vitamin K-dependent protein that serves as a cofactor for the inhibition of activated factor X by the serpin protein Z-dependent protease inhibitor (ZPI). Protein Z plasma levels have been shown to be reduced in patients with peripheral arterial disease (PAD), but ZPI levels have not yet been reported. The aim of this study was to more fully assess the protein Z-ZPI system in individuals with atherosclerosis selected by the presence of symptomatic PAD.

MATERIALS AND METHODS

Protein Z and ZPI levels were determined in 95 PAD patients (73 males; 22 females) [median age: 73 years (range, 50-86 years)] and in 190 controls comparable for age and gender. Protein Z was measured using a commercial immunoassay, and ZPI was measured with a homemade immunoassay and a functional assay.

RESULTS

Protein Z antigen, ZPI antigen and ZPI function were found to be significantly lower in PAD patients with respect to controls [protein Z, median 72.5% (range: 3.4-123.7%) vs. 90.7% (range: 32.1-203.2%), P < 0.0001; ZPI antigen, 86.1% (range: 25.1-149.5%) vs. 93.2% (range: 48.9-171.3%), P = 0.004; ZPI function, 83.5% (range: 21.1-135.2%) vs. 97.2% (range: 50.5-175.5%), P < 0.0001]. The lowest tertiles of protein Z antigen [odds ratio (OR) 5.4, 95% confidence interval (CI) 2.2-13.5, P < 0.0001] and ZPI function (OR 2.4, 95% CI 1.1-5.5, P = 0.03) were associated with PAD on multivariate analysis after adjustment for age, gender, and traditional cardiovascular risk factors. A significant inverse relationship was also observed between protein Z and ZPI levels and the number of traditional cardiovascular risk factors and the clinical severity of disease (Fontaine stage).

CONCLUSIONS

Low levels of protein Z antigen and protein Z activity are significantly associated with the occurrence and severity of atherosclerotic PAD.

Lipid, inflammatory and haemorheological profiles are significantly affected by farmed fish eating: an intervention study

AIM

The objective of the present study was to evaluate the influence of short-term dietary intake of farmed fish on biomarkers related to the atherosclerotic process.

METHODS AND RESULTS

Lipid, inflammatory, and haemorheological variables before (T0) and after a dietary intervention with about 800 g Orbetello farmed sea bass per week for 10 weeks (T1) were evaluated in nine dyslipidemic subjects. Fish intake significantly decreased triacylglycerols (T1, 140.2+/-20.3 mg/dl versus T0, 183.3+/-29.2 mg/dl; P =0.04), whereas no significant changes for the other lipid variables have been observed. Moreover, dietary intervention significantly (P <0.05) decreased all of the inflammatory parameters investigated; namely, high-sensitivity C-reactive protein, interleukin-6, and interleukin-8. Furthermore, a significant (P =0.04) improvement in erythrocytes' deformability index was reported after 10 weeks of fish dietary intake (9.0+/-0.7% versus 5.4+/-1.0% for T1 and T0, respectively).

CONCLUSION

Dietary short-term intake of farmed fish seems to impose favourable biochemical changes in dyslipidemic subjects.

Relationship between exercise capacity, endothelial progenitor cells and cytochemokines in patients undergoing cardiac rehabilitation

No data are available about the possible role of endothelial progenitor cells (EPCs), cytochemokines and N-terminal pro-brain natriuretic peptide (NT-proBNP) in determining a different response to short period of cardiologic rehabilitation (CR), as measured by the improvement of exercise capacity. In a population of 86 cardiac surgery patients, we evaluated the numbers of EPCs, pro- and anti-inflammatory cytokines (IL-6, IL-8, IL-10, IL-1ra), hs-C-reactive protein (CRP), vascular endothelial growth factor (VEGF) and NT-proBNP before (T1), and after 15 days of CR (T2). EPCs were measured by flow cytometry, and the exercise capacity was measured at T1 and T2 by using the six-minute walk test (6MWT). At T2, a significant increase of 6MWT (p<0.0001) was detected. No significant increase of EPCs was observed, while a significant (at least p<0.05) decrease in cytochemokines, CRP and NT-ProBNP levels was evidenced. By analyzing the median improvement of 6MWT, only patients with a median improvement > or = 23% showed a significant (p<0.05) increase of EPCs at T2, with significant correlations between EPCs, VEGF and IL-10. On the contrary, in patients with a median improvement <23% a negative correlation between CRP and EPCs was observed. Finally, CD34+/KDR+ EPCs showed significant correlation with IL-8 at T1. In conclusion, a short period of CR intervention determines a different pattern of modifications for EPCs in relation to the improvement of exercise capacity.

Adherence to Mediterranean diet and health status: meta-analysis

OBJECTIVE

To systematically review all the prospective cohort studies that have analysed the relation between adherence to a Mediterranean diet, mortality, and incidence of chronic diseases in a primary prevention setting.

DESIGN

Meta-analysis of prospective cohort studies.

DATA SOURCES

English and non-English publications in PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials from 1966 to 30 June 2008. Studies reviewed Studies that analysed prospectively the association between adherence to a Mediterranean diet, mortality, and incidence of diseases; 12 studies, with a total of 1 574,299 subjects followed for a time ranging from three to 18 years were included.

RESULTS

The cumulative analysis among eight cohorts (514,816 subjects and 33,576 deaths) evaluating overall mortality in relation to adherence to a Mediterranean diet showed that a two point increase in the adherence score was significantly associated with a reduced risk of mortality (pooled relative risk 0.91, 95% confidence interval 0.89 to 0.94). Likewise, the analyses showed a beneficial role for greater adherence to a Mediterranean diet on cardiovascular mortality (pooled relative risk 0.91, 0.87 to 0.95), incidence of or mortality from cancer (0.94, 0.92 to 0.96), and incidence of Parkinson's disease and Alzheimer's disease (0.87, 0.80 to 0.96).

CONCLUSIONS

Greater adherence to a Mediterranean diet is associated with a significant improvement in health status, as seen by a significant reduction in overall mortality (9%), mortality from cardiovascular diseases (9%), incidence of or mortality from cancer (6%), and incidence of Parkinson's disease and Alzheimer's disease (13%). These results seem to be clinically relevant for public health, in particular for encouraging a Mediterranean-like dietary pattern for primary prevention of major chronic diseases.

ADAMTS-13 activity in the presence of elevated von Willebrand factor levels as a novel mechanism of residual platelet reactivity in high risk coronary patients on antiplatelet treatment

BACKGROUND

The pathophysiologic mechanisms leading to residual platelet reactivity (RPR) on antiplatelet therapy, a condition high prevalent in patients with acute coronary syndrome, are not yet elucidated. In the acute phase of coronary artery disease large amounts of ultra large VWF multimers (ULVWF) are released and cleaved by the activity of ADAMTS-13.

OBJECTIVE

Aim of this study was to evaluate the relationships between VWF antigen (VWF:Ag) levels, collagen binding activity of VWF (VWF:CB), ADAMTS-13 and interleukin-6 (IL-6) levels in affecting platelet response to dual antiplatelet treatment.

METHODS

In 159 acute coronary syndrome (ACS) patients undergoing percutaneous coronary interventions we measured platelet function by platelet aggregation with two agonists [1 mM arachidonic acid (AA) and 10 microM ADP]. We defined patients with RPR those with platelet aggregation by AA >20% and/or ADP (10 micromol) >70%.

RESULTS

We found significantly lower ADAMTS-13 activity, elevated IL-6, VWF:Ag and VWF:CB levels in patients with RPR. A lower ADAMTS-13 activity was present in patients with VWF:Ag and VWF:CB in the upper tertile. At the multivariate analysis ADAMTS-13 activity and IL-6 were independent risk factors for RPR.

CONCLUSION

Our results indicate that ADAMTS-13 activity and IL-6 levels independently affect RPR and suggest that, by different pathways, both are involved in the variable response to antiplatelet therapy.