Intertwining of thrombosis and inflammation in atherosclerosis

Inflammation in atherosclerosis: from vascular biology to biomarker discovery and risk prediction

Recent investigations of atherosclerosis have focused on inflammation, providing new insight into mechanisms of disease. Inflammatory cytokines involved in vascular inflammation stimulate the generation of endothelial adhesion molecules, proteases, and other mediators, which may enter the circulation in soluble form. These primary cytokines also induce production of the messenger cytokine interleukin-6, which stimulates the liver to increase production of acute-phase reactants such as C-reactive protein. In addition, platelets and adipose tissue can generate inflammatory mediators relevant to atherothrombosis. Despite the irreplaceable utility of plasma lipid profiles in assessment of atherosclerotic risk, these profiles provide an incomplete picture. Indeed, many cardiovascular events occur in individuals with plasma cholesterol concentrations below the National Cholesterol Education Program thresholds of 200 mg/dL for total cholesterol and 130 mg/dL for low-density lipoprotein (LDL) cholesterol. The concept of the involvement of inflammation in atherosclerosis has spurred the discovery and adoption of inflammatory biomarkers for cardiovascular risk prediction. C-reactive protein is currently the best validated inflammatory biomarker; in addition, soluble CD40 ligand, adiponectin, interleukin 18, and matrix metalloproteinase 9 may provide additional information for cardiovascular risk stratification and prediction. This review retraces the biology of atherothrombosis and the evidence supporting the role of inflammatory biomarkers in predicting primary cardiovascular events in this biologic context.

Regulation of tissue factor procoagulant activity by post-translational modifications

Post-translational modification of amino acid residues is a common way to regulate localization, stability and ultimately the function of the protein. Tissue factor (TF), the major initiator of blood coagulation cascade, receives several post-translational modifications, like glycosylation, phosphorylation, palmitoylation and nitrosylation. Recent studies have demonstrated that these processes play important roles in modulating biological functions of TF. The present review highlights the mechanisms of several common protein post-translational modifications of TF with the special reference on the recent knowledge about their roles in regulation of trafficking, stability as well as procoagulant and signaling functions of TF.

Cytokines and plasma factors in sickle cell disease

PURPOSE OF REVIEW

Plasma cytokines and related factors represent a burgeoning area of inquiry related to the pathogenesis in sickle cell disease. Cytokines derived from platelets, white blood cells and endothelial cells have all been implicated in the development of several sequelae of this disease. In this review, we seek to provide an overview of the noted and potentially novel roles for several key plasma factors in sickle cell disease. We also consider the putative role for those cytokines implicated by genetic analysis in sickle cell disease, but where the pathogenic, or ameliorative, role has yet to be determined.

RECENT FINDINGS

New roles for the platelet as a key mediator in the release of cytokines in sickle cell disease have recently been demonstrated. Angiogenic and inflammatory factors are also being explored in this illness. Members of the vascular endothelial growth factor and transforming growth factor-beta superfamilies have been suggested to contribute to several key events in pathogenesis of sickle cell disease, but with the promise of nitrous oxide therapy in this disorder, these cytokines merit a fresh perspective in the context of sickle cell disease.

SUMMARY

Increased understanding of the origin and pathology of cytokine levels in sickle cell disease may provide novel therapeutic approaches in the management of the disease.

Effects of scaling and root planing and sub-antimicrobial dose doxycycline on oral and systemic biomarkers of disease in patients with both chronic periodontitis and coronary artery disease

OBJECTIVES

This study evaluated the effects of scaling and root planing (SRP) +/- sub-antimicrobial dose doxycycline (SDD) on gingival crevicular fluid (GCF) levels of matrix metalloproteinase (MMP) -1, -8, -13 and on serum levels of high-sensitivity C-reactive protein (HsCRP) and lipid fractions in patients with both chronic periodontitis (CP) and coronary artery disease (CAD).

MATERIAL AND METHODS

Thirty-six patients were randomly distributed into two groups (Placebo or SDD; 6 weeks) and both received two regimens of SRP. At baseline and 6 weeks, GCF and blood were collected and clinical indices were recorded. MMPs, HsCRP and lipid fractions were assayed.

RESULTS

There were statistically significant improvements for all clinical parameters, GCF volumes, GCF MMPs and serum levels of HsCRP, apolipoprotein-A (APO-A), high-density lipoprotein (HDL) and lipoprotein-a between pre- and post-treatment in both groups. Between groups, there were statistically significant greater improvements in pocket depth (PD), gingival index (GI), APO-A and HDL, favouring the group receiving SDD adjunctive to SRP (p < 0.05).

CONCLUSION

Greater improvement was detected for PD and GI, and for serum levels of APO-A and HDL cholesterol when using SRP+SDD compared with SRP+placebo in this study. An investigation with larger numbers of patients and a longer duration of drug treatment is needed to confirm these preliminary findings.