Free protein S level as a risk factor for coronary heart disease and stroke in a prospective cohort study of healthy United Kingdom men

Ramadan intermittent fasting is associated with improved anticoagulant activity among healthy people: a case-control study

Data on the pathophysiological mechanisms of hemostatic alterations in the thrombotic events that occur during Ramadan intermittent fasting (RIF), particularly in the natural coagulation inhibitors, are very limited. Thus, our objective was to evaluate the effect of RIF on the natural anticoagulants level, antithrombin, protein C, and total and free protein S (PS) in healthy participants. Participants were divided into two groups. Group I consisted of 29 healthy fasting participants whose blood samples were taken after 20 days of fasting. Group II included 40 healthy non-fasting participants whose blood samples were taken 2-4 weeks before the month of Ramadan. Coagulation screening tests including prothrombin time (PT), activated partial thromboplastin time (APTT) and plasma fibrinogen level, natural anticoagulants; antithrombin, protein C, free and total PS and C4 binding protein (C4BP) levels were evaluated in the two groups. High levels of total and free PS without change in antithrombin, protein C, and C4BP levels were noted in the fasting group as compared with non-fasting ones (p < 0.05). PT and APTT showed no difference between the two groups. However, the fibrinogen level was higher in the fasting group. In conclusion, RIF was found to be associated with improved anticoagulant activity in healthy participants, which may provide temporal physiological protection against the development of thrombosis in healthy fasting people.

Dysregulation of metalloproteins in ischemic heart disease patients with systolic dysfunction

Ischemic heart disease (IHD) is the leading cause of mortality worldwide. Metalloproteins have been linked to human health and diseases. The molecular functions of metalloproteins in IHD is not well understood and require further exploration. The objective of this study was to find out the role of metalloproteins in the pericardial fluid of IHD patients having normal (EF > 45) and impaired (EF < 45) left ventricular ejection fraction (LVEF). IHD patients were grouped into two categories: LVEF<45 (n = 12) and LVEF >45 (n = 33). Pooled samples of pericardial fluid were fractionated by using ZOOM-isoelectric focusing (IEF) followed by further processing using one-dimensional gel electrophoresis (1D SDS-PAGE) and filter-aided sample preparation (FASP). Tryptic peptides of each fraction and differential bands were then analyzed by nano-LC-ESI-MS/MS. Protein identification was performed through a Mascot search engine using NCBI-Prot and SwissProt databases. A total of 1082 proteins including 154 metalloproteins were identified. In the differential bands, 60 metalloproteins were identified, while 115 metalloproteins were identified in all ZOOM-IEF fractions. Twelve differentially expressed metalloproteins were selected in the intense bands according to their molecular weight (MW) and isoelectric point (pI). The 12 differentially expressed metalloprotein includes ceruloplasmin, Prothrombin, Vitamin K-dependent protein, Fibulin-1, Ribosomal protein S6 kinase alpha-6, nidogen, partial, Serum albumin, Hemopexin, C-reactive protein, Serum amyloid P-component, and Intelectin-1 protein which were all up-regulated while serotransferrin is the only metalloprotein that was down-regulated in impaired (LVEF<45) group. Among the metalloproteins, Zn-binding proteins are 36.5 % followed by Ca-binging 32.2 %, and Fe-binging 12.2 %. KEGG, pathway analysis revealed the association of ceruloplasmin and serotransferrin with the ferroptosis pathway. In conclusion, 154 metalloproteins were identified of them the Zn-binding protein followed by Ca-binding and Fe-binding proteins were the most abundant metalloproteins. The two metalloproteins, the Cu-binding protein ceruloplasmin, and Fe-binding protein serotransferrin are involved in the ferroptosis pathway, an iron-dependent form of regulated cell death that has been linked to cardiac pathology, especially in IHD patients having impaired systolic (LVEF<45) dysfunction. However, further research is required to validate these findings.

A Systematic Review and Meta-Analysis of Advanced Biomarkers for Predicting Incident Cardiovascular Disease among Asymptomatic Middle-Aged Adults

Cardiovascular disease (CVD) continues as the most important cause of mortality. Better risk screening and prediction are needed to reduce the cardiovascular disease burden. The aim of the study was to assess the role of serum biomarkers in the prediction of CVD among asymptomatic middle-aged adults with no prior CVD history. A systematic review and meta-analysis were carried out using literature from PubMed and following PRISMA reporting guidelines. Twenty-five studies met our inclusion criteria and were included in the systematic review. The most commonly studied biomarker was high-sensitivity C reactive protein (hs-CRP) (10 studies), which showed that higher hs-CRP levels are associated with an increased risk of subsequent CVD events and mortality. In addition, several less-studied biomarkers (N-terminal pro-brain natriuretic peptide (NT-proBNP), fibrinogen, gamma-glutamyl transferase (GGT), and others) also showed significant associations with greater future risk of CVD. A meta-analysis was possible to perform for hs-CRP and NT-proBNP, which showed statistically significant results for the ability of hs-CRP (hazard ratio (HR) 1.19, (95% CI: 1.09−1.30), p < 0.05) and NT-proBNP (HR 1.22, (1.13−1.32), p < 0.05) to predict incident CVD among middle-aged adults without a prior CVD history or symptoms. Several serum biomarkers, particularly hs-CRP and NT-proBNP, have the potential to improve primary CVD risk prevention among asymptomatic middle-aged adults.

Association of Nitric Oxide Synthase Polymorphism and Coagulopathy in Patients with Osteonecrosis of the Femoral Head

Genetic polymorphism of nitric oxide synthase (NOS) can cause reduction of nitric oxide (NO) levels and may be associated with osteonecrosis of the femoral head (ONFH). However, the association of coagulopathy and NOS polymorphism in ONFH patients has not been confirmed. Between November 2005 and October 2013, 155 patients with ONFH were recruited in the study of serum coagulation profiles and NOS polymorphism. Another 43 patients who had dysplasia, osteoarthritis, or trauma of hip joints were included as controls. PCR genotyping for the analysis of NOS 27-bp polymorphism in intron 4 was performed. The analysis of coagulation profiles included fibrinogen, fibrinogen degradation product (FDP), protein S, protein C, and anti-thrombin III. The results showed that 27-bp repeat polymorphism was significantly associated with ONFH (OR 4.32). ONFH patients had significantly higher fibrinogen, FDP, protein S, and anti-thrombin III levels than that of the controls. The incidence of coagulopathy was significantly higher in ONFH patients (73.2%), and the odds ratio increased from 2.38 to 7.33 when they had 27-bp repeat polymorphism. Patients with hyperfibrinogenemia, elevated FDP levels, and with the risk factor of alcohol or steroid use had significantly higher risks of bilateral hip involvement. This study demonstrated the presence of NOS polymorphism, and a resultant reduction in NO production was associated with coagulopathy, which in turn might contribute to higher risks of bilateral ONFH. Our data suggests that checking NOS polymorphism and coagulopathy may provide a new avenue in managing ONFH.

Rivaroxaban in Recurrent Ischemic Stroke Due to Protein S Deficiency: A Case Report

Protein S deficiency is a thrombophilia associated with an increased risk of thromboembolism. Previous studies have shown its role as a predisposing factor for venous thromboembolism, but its role in recurrent arterial ischemic stroke remains uncertain. Here we report a patient with recurrent ischemic stroke due to protein S deficiency. Oral anticoagulant treatment with vitamin K antagonist (VKA) drugs is used to treat and prevent thromboembolic events caused by thrombophilia, but it has many limitations, especially in the case of recurrent thromboembolic events. Direct oral anticoagulants (DOACs) have many advantages over VKA. Previous studies have shown that they are safe in cases of thrombophilia, but they are not well studied in recurrent ischemic stroke due to protein S deficiency. In this study our patient was treated with rivaroxaban. Protein S deficiency may be a predisposing factor in recurrent ischemic stroke, and rivaroxaban can be a safe and effective treatment option. Further studies are needed to confirm our findings.

Vitamin K, Vascular Calcification, and Chronic Kidney Disease: Current Evidence and Unanswered Questions

More than 15% of the US population is currently >65 y old. As populations age there is a concomitant increase in age-related chronic diseases. One such disease is chronic kidney disease (CKD), which becomes more prevalent with age, especially over age 70 y. Individuals with CKD are at increased risk of cardiovascular disease, in part because arterial calcification increases as kidney function declines. Vitamin K is a shortfall nutrient among older adults that has been implicated in arterial calcification. Evidence suggests CKD patients have low vitamin K status, but data are equivocal because the biomarkers of vitamin K status can be influenced by CKD. Animal studies provide more compelling data on the underlying role of vitamin K in arterial calcification associated with CKD. The purpose of this review is to evaluate the strengths and limitations of the available evidence regarding the role of vitamin K in CKD.

TAM receptors in cardiovascular disease

The TAM receptors are a distinct family of three receptor tyrosine kinases, namely Tyro3, Axl, and MerTK. Since their discovery in the early 1990s, they have been studied for their ability to influence numerous diseases, including cancer, chronic inflammatory and autoimmune disorders, and cardiovascular diseases. The TAM receptors demonstrate an ability to influence multiple aspects of cardiovascular pathology via their diverse effects on cells of both the vasculature and the immune system. In this review, we will explore the various functions of the TAM receptors and how they influence cardiovascular disease through regulation of vascular remodelling, efferocytosis and inflammation. Based on this information, we will suggest areas in which further research is required and identify potential targets for therapeutic intervention.

Hypercoagulable states in arterial and venous thrombosis: When, how, and who to test?

Evaluation for underlying hypercoagulable states in patients with thrombosis is a frequent clinical conundrum. Testing for thrombophilias is often reflexively performed without strategic approach nor clear appreciation of the clinical implications of such results. Guidelines vary in the appropriate utilization of thrombophilia testing. In this review, we discuss the more commonly encountered inherited and acquired thrombophilias, their association with initial and recurrent venous thromboembolism, arterial thromboembolism, and role in women's health. We suggest an approach to thrombophilia testing guided by the clinical presentation, suspected pathophysiology, and an understanding of how such results may affect patient care.

Relationship between plasma protein S levels and apolipoprotein C-II in Japanese middle-aged obese women and young nonobese women

: Protein S, a nonenzymatic cofactor to activated protein C, presents in two forms in plasma, free form and in a complex with C4b-binding protein. The aim of this study was to determine the association of plasma protein S levels with the variables related to cardiovascular disease risk. The relationships between plasma protein S levels with lipids, inflammation markers, and adiposity were first examined on middle-aged obese women (n = 62), then on young nonobese women (n = 160) to verify the findings in the obese women. Total and free protein S antigen levels in middle-aged obese women, approximately half being in a postmenopausal state and suffered from dyslipidemia, correlated negatively with estradiol and positively with triglycerides, total cholesterol, LDL cholesterol, apoA-II, apoB, apoC-II, apoC-III, apoE, hemoglobin A1c, and protein C, whereas there was no correlation with HDL cholesterol, apoA-I, BMI, visceral fat area, blood pressure, or factor VII activity. Multiple linear regression analyses revealed that protein C, apoC-II, and fibrinogen were significant predictors of total protein S antigen levels, accounting for 51.9% of variance, and apoC-II as a singular significant predictor for free protein S antigen levels (12.3% of variance). In young nonobese women, most being normolipidemic, apoC-II was also selected as a significant predictor of total protein S antigen levels, but not of free protein S antigen levels. The positive relationship between plasma protein S levels and apoC-II, a key regulator of triglycerides hydrolysis, may contribute to the pathogenesis of increased concentrations of plasma protein S.

Protein S levels and the risk of venous thrombosis: results from the MEGA case-control study

Low free protein S and low total protein S levels could not identify subjects at risk for venous thrombosis in a population-based study. Protein S testing and subsequent testing on PROS1 mutations should not be considered in unselected patients with venous thrombosis.