Fibrinogen as a cardiovascular risk factor in Spanish children and adolescents. The Niño Jesus Group

Application of Extracellular Vesicles Proteomics to Cardiovascular Disease: Guidelines, Data Analysis, and Future Perspectives

Extracellular vesicles (EVs) are a heterogeneous population of vesicles composed of a lipid bilayer that carry a large repertoire of molecules including proteins, lipids, and nucleic acids. In this review, some guidelines for plasma-derived EVs isolation, characterization, and proteomic analysis, and the application of the above to cardiovascular disease (CVD) studies are provided. For EVs analysis, blood samples should be collected using a 21-gauge needle, preferably in citrate tubes, and plasma stored for up to 1 year at -80°, using a single freeze-thaw cycle. For proteomic applications, differential centrifugation (including ultracentrifugation steps) is a good option for EVs isolation. EVs characterization is done by transmission electron microscopy, particle enumeration techniques (nanoparticle-tracking analysis, dynamic light scattering), and flow cytometry. Regarding the proteomics strategy, a label-free and gel-free quantitative method is a good choice due to its accuracy and because it minimizes the amount of sample required for clinical applications. Besides the above, main EVs proteomic findings in cardiovascular-related diseases are presented and analyzed in this review, paying especial attention to overlapping results between studies. The latter might offer new insights into the clinical relevance and potential of novel EVs biomarkers identified to date in the context of CVD.

[Values of high-density lipoprotein cholesterol in the pediatric population and risk of thrombosis]

INTRODUCTION

There is evidence of the protective effect of high-density lipoprotein (HDL)-cholesterol against atheroma plaque formation and of its role in cholesterol efflux from cells, as well as its anti-oxidative and inflammatory modulating response properties. Low HDL-cholesterol levels have been associated with a prothrombotic state.

OBJECTIVE

To determine the relationship between HDL-cholesterol and lipidic and hemostatic parameters.

PATIENTS AND METHODS

We studied 110 children (50 girls, 60 boys) aged between 6 and 7 years old. Lipid profile, D-dimer, plasminogen activator inhibitor (PAI) and fibrinogen were determined.

RESULTS

The mean values of the studied parameters were as follows: total cholesterol (192.92+/-26.01 mg/dl), HDL-cholesterol (72.87+/-15.69 mg/dl), low-density lipoprotein-cholesterol (109.46+/-23.30 mg/dl), triglycerides (56.24+/-20.35 mg/dl), apolipoprotein B (91.96+/-14.93 mg/dl), apolipoprotein A1 (168.4+/-24.55 mg/dl), lipoprotein(a) logarithm (1.76+/-1.36 mg/dl), plasminogen activator inhibitor-1 logarithm (PAI-1) (3.77+/-3.93 U/ml), D-dimer logarithm (5.53+/-0.49 ng/ml) and fibrinogen (268.61+/-48.59 mg/dl). When the sample was divided into two groups according to HDL-cholesterol levels, children with lower levels showed significantly higher values of total cholesterol/HDL-cholesterol, fibrinogen and PAI. HDL-cholesterol levels were directly and significantly associated with total cholesterol and apolipoprotein A1 and negatively and significantly associated with the total cholesterol/HDL-cholesterol ratio, fibrinogen and PAI.

CONCLUSION

The children studied had high HDL-cholesterol levels, which could be responsible for the high total cholesterol levels. High values of HDL-cholesterol are significantly associated with a reduction in thrombotic risk.

Plasma fibrinogen levels and cardiovascular risk factors in Japanese schoolchildren

BACKGROUND

Plasma fibrinogen level has been recognized as an independent risk factor for atherosclerosis and its thrombotic complications in adults. The present study aimed to clarify the association between plasma fibrinogen levels and cardiovascular risk factors in Japanese children.

METHODS

A total of 294 schoolchildren (145 boys and 149 girls) aged 10-13 years in a town in Nagano Prefecture, Japan, were surveyed in 2000 for body mass index (BMI), plasma fibrinogen, serum C-reactive protein (CRP), serum total cholesterol, serum high-density lipoprotein (HDL) cholesterol, hemoglobin (Hb) A1c, and ratio of serum total cholesterol to serum HDL cholesterol (TCHR).

RESULTS

The mean value and standard deviation of plasma fibrinogen level among the schoolchildren was 226.0+/-39.7 mg/dL for boys and 245.3+/-40.9 mg/dL for girls; significantly higher for girls. Among plasma fibrinogen tertiles, serum CRP tended to increase with plasma fibrinogen in both boys and girls. An increasing trend was also found in serum total cholesterol in boys, and in TCHR, HbA1c and BMI in girls. Multiple linear regression analysis revealed significant associations of plasma fibrinogen with serum CRP and HbA1c in both sexes, with TCHR in boys, and with BMI in girls.

CONCLUSIONS

Plasma fibrinogen levels were associated with cardiovascular risk factors such as serum CRP, TCHR, HbA1c, and BMI in Japanese schoolchildren.

Fibrinogen, homocyst(e)ine, and C-reactive protein concentrations relative to sex and socioeconomic status in British young people

This study assesses the prevalence of recently identified coronary heart disease (CHD) risk factors in young people of differing socioeconomic status (SES). From November 2001 through March 2002, 100 boys and 108 girls, of age 12.9 +/- 0.3 years, selected from differing SES were assessed for CHD risk factors. Measurements included fibrinogen (Fg), homocyst(e)ine (Hcy), and C-reactive protein (CRP). Fibrinogen was significantly greater among boys from a higher SES compared with those from a low SES (P < or = 0.05). Differences according to sex (P < or = 0.05) were identified for Fg and CRP. The data indicate the prevalence of recently identified CHD risk factors in this cohort of British schoolchildren. For the purpose of this article, the phrase "young people" embraces both children and adolescents.

Established and recently identified coronary heart disease risk factors in young people: the influence of physical activity and physical fitness

Epidemiological studies have identified several risk factors for coronary heart disease (CHD), many of which are present in young people. [For the purpose of this review, the phrase "young people" embraces both children and adolescents.] One such risk factor is hypertension. In adults, exercise is thought to have a positive effect on blood pressure levels; however, findings are inconclusive for young people. Despite its association with CHD, obesity is on the increase in Western society's young population; prevention and intervention during early years is needed. An active lifestyle is considered to have a beneficial effect on body fatness. Lipoprotein profiles are directly associated with CHD status. In adults, there is some evidence that physical activity and/or fitness have a favourable effect on lipoprotein levels. Although information regarding the younger population is more ambiguous, it tends to concur with these findings. High levels of lipoprotein(a), are considered an independent risk factor for CHD. Relatively little has been written on young people, although some studies have postulated a favourable relationship with physical activity. An inverse relationship between aerobic fitness and CHD has been confirmed in adults; an association is not as easily verified for young people. Physical activity is similarly deemed to have a beneficial effect on health status. A high-fat diet has been linked to CHD in adults, and evidence to date reports similar findings for young people. Smoking increases the risk of CHD and even moderate smoking during youth could have damaging long-term consequences. There is some evidence that smoking is related to physical activity and fitness levels in young people. In adults, high levels of homocyst(e)ine have been associated with CHD. As yet, little has been written on the relationship between physical activity or physical fitness and homocysteine status in young people. High levels of plasma fibrinogen have been linked to CHD. Several studies have explored the relationship between plasma fibrinogen and physical activity and/or fitness in adults, but findings are inconclusive; for young people, the ambiguity is even greater. C-reactive protein is a molecular marker for CHD but, to date, little attention has been given to this aspect, especially amongst young people. The link between high levels of plasminogen activator inhibitor-1 and CHD has been confirmed, although the essence of this relationship is not established. There is a paucity of data on the younger population and the relevance of collating such information is questionable. For the younger population, most research is limited to the established CHD risk factors and further investigations of recently identified CHD risk factors are needed.

The influence of smoking on von Willebrand factor is already manifest in healthy adolescent females: the Floren-teen (Florence Teenager) Study

The early onset of atherosclerosis and the involvement of physiological biochemical, and environmental factors in its pathogenesis is well documented. Few data are available on the role of risk factors related to hemostasis in the pathogenesis of atherosclerosis in the young and, in particular, little information is available on adolescent populations. In the Study of Preventive Medicine and Education Program (Floren-teen Study), von Willebrand factor, a risk factor for cardiovascular disorder, was studied, together with classical cardiovascular risk factors, in apparently healthy students from two high schools in Florence. Familial and personal history, physical examination, and cardiovascular risk factors were evaluated in 144 students (aged 17-19 years). Blood was withdrawn to assess von Willebrand factor (ELISA) and lipid parameters. Levels of von Willebrand factor were significantly higher (P<0.044) in smokers than in nonsmokers and were correlated with the number of cigarettes per day in the whole group (P=0.01) and in females (P=0.006). In females a positive correlation was observed between von Willebrand factor and high-density lipoprotein cholesterol (P=0.0365). There was no significant correlation between von Willebrand factor and blood pressure or between von Willebrand factor and physical activity. In conclusion, this study shows an association between levels of von Willebrand factor and smoking habits and is the first show that even a brief period of smoking affects levels of von Willebrand factor in healthy adolescent females independently of other risk factors. These results stress the relevance of extending prevention programs to reduce smoking in high school students.

Serum lipids and apolipoproteins in Spanish children and adolescents: a 5 year follow-up

This study was designed to assess "tracking" of serum lipids and apolipoproteins in three age groups of Spanish children over a 5 year period. A total of 84 6-year-old, 89 10-year-old and 64 14-year-old children were evaluated in 1989 (with measurement of serum total cholesterol, triglycerides, lipoproteins and apolipoproteins A1 and B), and re-evaluated in 1994. Correlation coefficients between initial and final lipid and apolipoprotein values were as follows: total cholesterol, 0.66; low-density lipoprotein (LDL) cholesterol, 0.65; high-density lipoprotein (HDL) cholesterol, 0.61; triglycerides, 0.61; apolipoprotein A1, 0.60; apolipoprotein B, 0.66. When age groups were analysed separately, children who were 14 years old at the beginning of the study showed higher correlation coefficients, particularly for total cholesterol and LDL cholesterol ( > 0.7 in both cases). More than 70% of children who were in the top quintile of total, LDL or HDL cholesterol as well as apolipoprotein A1 or B in 1989 remained in the top quintile 5 years later.