C-Reactive Protein and High-Sensitivity C-Reactive Protein: An Update for Clinicians

Towards clinical applications of selected reaction monitoring for plasma protein biomarker studies

The widespread clinical adoption of protein biomarkers with diagnostic, prognostic and/or predictive value remains a formidable challenge for the biomedical community. From discovery to validation, the path to biomarkers of clinical relevance abounds with many protein candidates, yet so few concrete examples have been substantiated. In this review, we focus on the recent adoption of selected reaction monitoring (SRM) of plasma proteins in the path to clinical use for a broad range of diseases including cancer, cardiovascular disease, genetic disorders and various metabolic disorders. Recent progress reveals a promising outlook for clinical applications using SRM, which now provides the routine analysis of clinically relevant protein markers at low nanogram per millilitre in plasma.

Relation of physical activity to cardiovascular disease mortality and the influence of cardiometabolic risk factors

Physical activity can improve several metabolic risk factors associated with cardiovascular disease (CVD) and is associated with a lower risk of CVD mortality. We sought to evaluate the extent to which metabolic risk factors mediate the association between physical activity and CVD mortality and whether physical activity provides protective effects against CVD mortality in healthy adults and those with metabolic risk factors. A sample of 10,261 adults from the Third National Health and Nutrition Examination Survey with public-access mortality data linkage (follow-up 13.4 ± 3.9 years) was used. Physical activity was assessed by questionnaire and classified into inactive, light, and moderate/vigorous activity categories. Metabolic risk factors (dyslipidemia, type 2 diabetes mellitus, obesity, hypertension, inflammation, and insulin resistance) were categorized using clinical thresholds. After adjusting for basic confounders, engaging in light or moderate/vigorous physical activity was associated with a lower risk of CVD mortality (p < 0.05). Adjustment for each risk-factor set only slightly attenuated this relation. When all risk-factor sets were added to the model simultaneously, light (hazard ratio 0.72, 0.62 to 0.84) and moderate/vigorous (hazard ratio 0.72, 0.62 to 0.85) activity remained at lower risk of CVD mortality. In addition, physical activity provided protective effects for CVD mortality in healthy subjects and those with metabolic risk factors in isolation or in clusters. In conclusion, physical activity was associated with a lower risk of CVD mortality independent of traditional and inflammatory risk factors. Taken together these results suggest that physical activity may protect against CVD mortality regardless of the presence of metabolic risk factors.

Detection of suPAR in the Saliva of Healthy Young Adults: Comparison with Plasma Levels

The soluble urokinase plasminogen activator receptor (suPAR) has been detected in blood, plasma, serum, urine, ovarian cystic fluid, and cerebrospinal fluid. Elevated suPAR levels in plasma have been associated with negative outcomes in various diseases, such as bacteremia, sepsis, SIRS, cardiovascular disease, cancer, and tuberculosis. The primary aim of this study was to investigate whether suPAR can be detected in saliva from healthy individuals and thus, if saliva suPAR can be related to plasma suPAR, CRP, BMI, or gender. Blood and unstimulated whole saliva was collected from 20 healthy individuals (10 female and 10 male, median age of 28 years; range 21–41). CRP and suPAR were measured with ELISA in saliva and serum/plasma. suPAR was detected in all saliva samples in the 5.2–28.1 ng/mL range, with a median value of 17.1 ng/mL. Saliva suPAR was significantly higher (P < 0.001) but not correlated to plasma suPAR in healthy young adults with normal plasma suPAR levels. suPAR and CRP levels were correlated in blood but not in saliva. No correlation was found between BMI, age, or gender and suPAR in saliva.