The relation of apolipoprotein E polymorphism to multiple cardiovascular risk in children: the Bogalusa Heart Study

Lipid Biomarkers and Atherosclerosis-Old and New in Cardiovascular Risk in Childhood

Lipids are a complex group of molecules in the body, essential as structural, functional and metabolic components. When disbalanced, they are regarded as a cardiovascular risk factor, traditionally in cholesterol level evaluation. However, due to their complex nature, much research is still needed for a comprehensive understanding of their role in atherosclerosis, especially in the young. Several new lipid biomarkers are emerging, some already researched to a point, such as lipoproteins and apolipoproteins. Other lipid molecules are also being increasingly researched, including oxidized forms due to oxidative inflammation in atherosclerosis, and sphingolipids. For many, even those less new, the atherogenic potential is not clear and no clinical recommendations are in place to aid the clinician in using them in everyday clinical practice. Moreover, lipids' involvement in atherogenesis in children has yet to be elucidated. This review summarizes the current knowledge on lipids as biomarkers of cardiovascular risk in the paediatric population.

Metabolic syndrome in a sample of Egyptian adolescent girls and its association with apolipoprotein E

AIM

Obesity and its metabolic complications are increasing in childhood and extend to adulthood. The aims of this study were to assess the prevalence of metabolic syndrome (MS) in a sample of Egyptian adolescent girls and investigate its association with apolipoprotein E.

METHODS

A cross-sectional study design was used, including 200 Egyptian adolescent girls aged between 12 and 18 years. They were subjected to blood pressure (BP) measurement, anthropometric measurements (weight, height and waist circumference (WC)), laboratory investigations (fasting glucose and lipid profile) and molecular analysis (Apo E).

RESULTS

Overweight/obese girls were suffering significantly, more than normal-weight girls, from hypertension (66.7 vs. 40.8%), diabetes diagnosed by elevated fasting blood glucose (46.7 vs. 31.2%) and low high-density lipoprotein (HDL) (64 vs. 59.2%). Girls with MS had significantly higher values of body mass index Z-score, WC, BP, cholesterol and triglycerides and significantly lower HDL. Allele E3 (59.1 vs. 55.1%) was more frequent among girls with MS, while allele E4 (41 vs. 36.4) was more frequent among girls without MS. MS was the most prominent among girls with the E3/E4 genotype (35.7%), who had the highest frequency of elevated cholesterol, triglycerides, low-density lipoprotein and blood glucose, while girls with the E2/E4 genotype, which was rare among both groups, had the highest frequency of elevated BP (68.8%) and low HDL (71.4%).

CONCLUSION

MS was significantly more prominent among overweight/obese adolescent girls with the E3/E4 genotype, who had the highest frequency of disturbed lipid profile and blood glucose.

Association between Apolipoprotein E Variants and Obesity-Related Traits in Mexican School Children

BACKGROUND/AIM

Genetic variation in apolipoprotein E (ApoE) has a key role in lipid metabolism. However, its contribution to the amount and distribution of body fat is under investigation. The aim of this study was to analyze the association between genetic variation in ApoE and obesity-related traits in Mexican school children.

MATERIAL AND METHODS

Anthropometric, body composition and physical activity measures were conducted using standard methods in 300 children (177 girls/123 boys) who fulfilled the inclusion criteria. DNA was isolated from saliva. ApoE genotypes were analyzed by allelic discrimination. The association between variation in ApoE and anthropometric and body composition measures was investigated using the General Linear Model.

RESULTS

The mean±SD values for age, body mass index (BMI) and waist circumference (WC) were 9.05±0.80 years, 19.01±3.83 and 67.98±10.97 cm, respectively. Approximately 46% of the participants were overweight or obese. A significant association between ApoE isoforms and WC was found after controlling for age, sex and the percentage of physical activity (p=0.025). Significant main effects were found for vigorous physical activity and light physical activity influencing the adiposity-related BMI (p<0.001) and WC (p=0.044), respectively.

CONCLUSIONS

Variation in ApoE and physical activity intensity were associated with adiposity-related phenotypes in Mexican school children.

Lipoprotein Candidate Genes for Multivariate Factors of the Insulin Resistance Syndrome: A Sib-pair Linkage Analysis in Women Twins

The insulin resistance syndrome (IRS) is characterized by a combination of interrelated coronary heart disease risk factors, including low high-density lipoprotein cholesterol (HDLC) levels, obesity and increases in triglyceride (TG), systolic and diastolic blood pressure (BP), small low-density lipoprotein particles (LDL-size), and fasting and postload plasma insulin and glucose. Using factor analysis, we previously identified multivariate factors based on data from women participating in the Kaiser Permanente Women Twins Study: 1) Weight/Fat, 2) Insulin/Glucose, 3) Lipids, and 4) BP. The purpose of this study is to evaluate evidence for genetic linkage between the multivariate factors and candidate genes. Quantitative sib-pair analysis based on the factor scores with markers for 9 candidate genes was carried out based on data from 126 pairs of dizygotic (DZ) women twins from the second exam of the Kaiser Permanente Women Twins study. Suggestive evidence for linkage was found for the Weight/fat factor and the Apo E gene (p= 0.01), and stronger evidence for linkage with the Lipid factor and the cholesterol ester transfer protein (p= 0.002) gene. Therefore, the CETP gene appears to influence covariation in LDL size, TG, and HDL, and may account for a portion of the well-established statistical and metabolic associations observed between these risk factors.

Genetic variants in lipid metabolism are independently associated with multiple features of the metabolic syndrome

Background

Our objective was to find single nucleotide polymorphisms (SNPs), within transcriptional pathways of glucose and lipid metabolism, which are related to multiple features of the metabolic syndrome (MetS).

Methods

373 SNPs were measured in 3575 subjects of the Doetinchem cohort. Prevalence of MetS features, i.e. hyperglycemia, abdominal obesity, decreased HDL-cholesterol levels and hypertension, were measured twice in 6 years. Associations between the SNPs and the individual MetS features were analyzed by log-linear models. For SNPs related to multiple MetS features (P < 0.01), we investigated whether these associations were independent of each other.

Results

Two SNPs, CETP Ile405Val and APOE Cys112Arg, were associated with both the prevalence of low HDL-cholesterol level (Ile405Val P = < .0001; Cys112Arg P = 0.001) and with the prevalence of abdominal obesity (Ile405Val P = 0.007; Cys112Arg P = 0.007). For both SNPs, the association with HDL-cholesterol was partly independent of the association with abdominal obesity and vice versa.

Conclusion

Two SNPs, mainly known for their role in lipid metabolism, were associated with two MetS features i.e., low HDL-cholesterol concentration, as well as, independent of this association, abdominal obesity. These SNPs may help to explain why low HDL-cholesterol levels and abdominal obesity frequently co-occur.

The apolipoprotein E gene and Taq1A polymorphisms in childhood obesity

Obesity is a multifactorial disease that is influenced by genetic and environmental factors. The apolipoprotein E (Apo E) polymorphism has been reported to influence some lipid profile abnormalities associated with obesity in childhood. In this study, the relationship between the Apo E gene and Taq1A polymorphisms with childhood obesity has been studied. Regarding the Apo E genotypes, e3/4 was the most frequent in both the patient and control groups. Further, there was a significance between the Apo E genotypes with low density lipoprotein and total cholesterol levels. However, no relationship was found between the Taq1A polymorphism and obesity. In conclusion, polygenic inheritance should be kept in mind when dealing with childhood obesity.

Serum lipid and apolipoprotein profiles in newborns and six‐year‐old children: The Tallinn Young Family Study

Seventy children aged 6 years (34 boys, 36 girls) were studied for cardiovascular risk factors. Among the children 40 had also been investigated at birth. The aim of the study was to determine changes in serum lipoprotein parameters from birth up to preschool age and to assess the role of some relevant factors that might affect the process. An obvious association was found between serum apolipoprotein (apo) B levels, the apoB/apoA-I ratio and lipoprotein(a) (Lp(a)) levels at birth and at 6 years of age (r = 0.43; p<0.05, r = 0.73; p<0.0001 and r = 0.81; p<0.0001, respectively). Thirty percent of children who were in the top quartile by apoB or total cholesterol levels and 66.7% of those in this quartile by apoB/apoA-I ratio at birth remained in the top quartiles also in the follow-up study. The significantly higher apoB/apoA-I ratio in newborns and the apoB/apoA-I and apoB values in the 6-year-old children were observed in the carrier apoE4 isoform as compared to E3 homozygotes. A significant influence of apoE polymorphism on serum apoB/apoA-I ratio and apoB level in preschool children was confirmed by ANOVA one-way analysis of variance. In a multiple regression analysis from all the studied factors, the independent determinants of apoB level in preschool age were apoE phenotype, gestational age and Apgar score in the first minute of life. Thus, tracking of serum Lp(a), apoB, apoB/apoA-I ratio and total cholesterol levels from birth up to 6 years of age was demonstrated. The association between apoE polymorphism and serum lipoprotein parameters became more obvious after the first 6 years of life.

Association of low-density lipoprotein particle size and ratio of different lipoproteins and apolipoproteins with coronary heart disease

BACKGROUND

Worldwide coronary heart disease (CHD) is estimated to be the leading cause of death. Current knowledge about prevention of CHD is mainly derived from developed countries. Therefore, this study aimed to find out the association of CHD with ratios of different lipoproteins and apolipoproteins, LDL particle size, as well as different traditional risk factors in Asian Indian population in Eastern part of India.

METHODS

Case-control study of 100 patients with CHD and 98 healthy controls were age and sex matched. After clinical evaluation, blood samples were collected for biochemical assays.

RESULTS

Multivariate logistic regression analysis found apoB (OR 2.96; 95% CI 1.02-8.54), apoB/HDL-c (OR 4.14; 95% CI 1.33-12.83), nonHDL-c (OR 5.41; 95% CI 2.08-14.10), apoB/apoAI (OR 6.64; 95% CI 2.37-18.57), and LDL particle size (9.59; 95% CI 2.92-31.54) were independently associated with CHD. Area under the ROC curves derived from the model (AUROC 0.947; 95% CI 0.916-0.977) are significantly higher than any other variables.

CONCLUSIONS

Findings from the multivariate analysis, apoB, apoB/HDL-c, nonHDL-c, apoB/apoAI, and LDL particle size are potent indicators and useful for diagnosis of predisposed CHD.

Apolipoprotein E polymorphism influences lipid phenotypes in Chinese families with familial combined hyperlipidemia

BACKGROUND

Apolipoprotein E (apoE) polymorphism is associated with changes in the lipoprotein profile of individuals with familial combined hyperlipidemia (FCHL), but its effects on the lipoprotein profiles of members of Chinese families with FCHL remain uncertain.

METHODS AND RESULTS

43 FCHL families (n=449) and 9 normolipidemic families (n=73) were recruited to assess the influence of apoE polymorphism on plasma lipids. The relative frequency of the epsilon4 allele in affected and unaffected FCHL relatives, spouses and normolipidemic members was 13.8%, 5.3%, 9.1% and 6.8%, respectively, with a significantly higher frequency in affected FCHL relatives, compared with unaffected FCHL relatives or normolipidemic members (p=0.0002 or p=0.029). In FCHL relatives, the apoE4 subset (E4/4 and E4/3) exhibited significantly higher levels of apoB, total cholesterol and low-density lipoprotein-cholesterol (LDL-C) than did the apoE3 (E3/3) subset, especially in women (all p<0.05), and there was significant elevation of LDL-C concentrations in men only (p<0.05). In men, the apoE2 (E3/2) subset indicated a decreased level of apoB and increased apoA1 compared with those in the apoE3 subset (p<0.05).

CONCLUSIONS

ApoE polymorphism appears to be associated with variance of the lipoprotein phenotype in Chinese families with FCHL.

Plasma Adhesion Molecules in Children With Sleep-Disordered Breathing

STUDY OBJECTIVES

To determine whether childhood sleep-disordered breathing (SDB) is associated with elevated levels of plasma adhesion molecules.

DESIGN

Prospective, observational study.

SETTING

Sleep Medicine Center of Kosair Children's Hospital.

PARTICIPANTS

Thirty-nine children with SDB (apnea-hypopnea index [AHI] > 5/h), 47 children with mild SDB (AHI 1 to 5/h), and 42 healthy control subjects (AHI < 1/h).

MEASUREMENTS AND RESULTS

One hundred twenty-eight children underwent a standard polysomnographic assessment with a blood draw the following morning. Plasma levels of CRP and the adhesion molecules intercellular adhesion molecule (ICAM)-1 and P-selectin were measured. No differences were observed in ICAM-1 levels among the groups; however, obese children had higher ICAM-1 levels than nonobese children (425.0 +/- 123.0 ng/mL vs 375.6 +/- 107.1 ng/mL, p = 0.04) [mean +/- SD]. P-selectin levels were significantly higher in the SDB group (84.0 +/- 52.2 ng/mL) and the mild SDB group (89.3 +/- 49.9 ng/mL) when compared to control subjects (49.5 +/- 22.3 ng/mL; p < 0.001 for both groups). Furthermore, P-selectin correlated with AHI (r = 0.32, p < 0.001), respiratory arousal index (r = 0.27, p = 0.002), and nadir of oxygen saturation as measured by pulse oximetry (r = - 0.19, p = 0.038). Plasma CRP levels were found to correlate with P-selectin even after controlling for BMI (r = 0.20, p = 0.05). No correlations were found between CRP and ICAM-1.

CONCLUSIONS

Children with SDB have plasma elevations of P-selectin, a marker of platelet activation, lending support to the premise that inflammatory processes are elicited by SDB in children, and may contribute to accelerated risk for cardiovascular morbidity. In contrast, elevations in ICAM-1 are primarily associated with obesity rather than SDB.

Gender, ethnicity and genetics in cardiovascular disease: part 1: Basic principles

Prior to 1993, most drug efficacy and safety trials were conducted in white males, although gender and racial differences in pharmacodynamics and pharmacokinetics have been documented since the early 1900s. Over the last 2 decades, supported by the FDA and legislation, attempts to include more women and minorities in clinical drug trials have been made, with limited success. Yet, there are important differences in pathophysiology and pharmacogenetics, as well as pharmacotherapeutic effectiveness. This is the first of 2 articles that review the basic scientific principles of such differences. In particular, genetic polymorphisms of cardiovascular candidate genes and drug metabolism are described. The pharmacodynamic and pharmacokinetic variations among genders and ethnicities are summarized.

Adipose fat quality vs. quantity: relationships with children's serum lipid levels

BACKGROUND

There is a controversy as to the relative importance of obesity vs quality of dietary fat in the prediction of serum lipoproteins in children. A reason for this is an apparent lack of studies implementing biomarkers of long-term dietary fat intake among children. The objective of the present study was to assess the relative contribution of degree of obesity, fat centrality, and quality of adipose tissue fat in the prediction of serum lipids in 12-year-old children.

METHODS

Pupils came from 40 schools randomly selected among 541 primary schools in three different provinces of the island of Crete. One thousand forty-six pupils were examined at age 6. At age 9, a representative sample from the original cohort (n = 579) was randomly selected for reevaluation. At the age of 12, a representative sample of 831 pupils was reexamined. At ages 6, 9, and 12, serum lipid measures were obtained from 941, 458, and 791 children, respectively. At age 12, data were obtained on pupils' anthropometry, serum lipids, dietary intake, physical fitness, and physical activity. Adipose tissue fatty acid data were obtained from a subsample of 194 children at age 12.

RESULTS

Regression analyses indicated that children's serum triglycerides related positively to body mass index and waist-hip ratio (WHR). Serum HDL-C related negatively to WHR and positively to endurance run test, an index of physical fitness. Dietary fatty acids, assessed by a single administration of 3-day weighed-food records, did not relate to serum lipids. However, serum HDL-C related negatively to sum of adipose polyunsaturated fatty acids, a measure of long-term polyunsaturated fat intake.

CONCLUSIONS

It appears that obesity and fat centrality are stronger predictors of children's serum lipids than the quality of long-term dietary fat intake or adipose tissue fatty acid composition. It is possible that this finding may relate to the particular subcutaneous depot studied. It is suggested that future studies study abdominal rather than buttock adipose tissue fatty acid composition in relation to children's serum lipid levels.

Apolipoprotein E phenotype regulates cholesterol absorption in healthy 13-month-old children--The STRIP Study

High serum cholesterol concentration is one of the key risk factors in development of atherosclerosis, which may begin early in life and later progress to symptomatic coronary heart disease. In adults, apoE polymorphism strongly influences cholesterol metabolism, as subjects with apoE 3/4 or 4/4 (collectively called apoE4) phenotype absorb cholesterol effectively and thus also have higher cholesterol absorption-reflecting plant sterol concentrations in serum than subjects with other apoE phenotypes. Because of the inverse correlation of absorption and synthesis of cholesterol, concentrations of cholesterol synthesis-reflecting serum cholesterol precursor sterols are lower in subjects with apoE4 than in subjects with other phenotypes. To analyze whether apoE phenotype affects cholesterol absorption and synthesis in early childhood, we measured serum plant sterol (campesterol and sitosterol) and cholesterol precursor sterol (desmosterol and lathosterol) concentrations in healthy 13-month old children using gas-liquid chromatography. The 36 study children were participants in a randomized prospective trial (the Special Turku Coronary Risk Factor Intervention Project) aimed at decreasing exposure of the children to environmental atherosclerosis risk factors. The 16 apoE4 children had 30% to 50% higher cholesterol-adjusted campesterol and sitosterol concentrations in serum than the 20 apoE 3/3 children (p = 0.002 and p = 0.02, respectively). The concentrations of cholesterol precursor sterols in serum did not differ between the two groups of children. We conclude that the young apoE4 children may absorb cholesterol and plant sterols more effectively than the children with apoE 3/3 phenotype without compensatory reduction in endogenous synthesis of cholesterol.

Lipoprotein and apolipoprotein abnormalities in familial combined hyperlipidemia: a 20-year prospective study

In order to characterize the lipoprotein abnormalities in familial combined hyperlipidemia (FCHL) and to describe factors associated with the stability of the FCHL phenotype during 20-year follow-up, 287 individuals from 48 families with FCHL originally identified in the early 1970s (baseline) were studied. Hyperlipidemia was defined as lipid-lowering medication use, or > or =age- and sex-specific 90th percentile for triglycerides or cholesterol. Triglyceride, cholesterol and medical history data were obtained at baseline and 20-year follow-up. Additional follow-up measures included HDL-C, LDL-C, LDL particle size, lipoprotein(a), apolipoprotein (apo) A-I, apoB, and apoE polymorphism. Longitudinally, two-thirds of relatives were consistently normolipidemic or hyperlipidemic, and one third were discordant for hyperlipidemic status at baseline and 20-year follow-up. Individuals with hyperlipidemia at baseline and/or follow-up had higher apoB levels than those with consistently normal lipids (P<0.05), whereas small LDL size was associated with concurrent hyperlipidemia. Among individuals who were normolipidemic at baseline, the following variables were independently associated with development of hyperlipidemia over 20 years: older age at baseline, male sex, greater increase in BMI during follow-up, and apoE alleles epsilon 2 or epsilon 4. In conclusion, apoB is associated with hyperlipidemia and apoE polymorphism is associated with later onset of hyperlipidemia in FCHL.

Apolipoprotein epsilon2 allele is associated with an anti-atherogenic lipoprotein profile in children: The Columbia University BioMarkers Study

OBJECTIVE

We examined associations between allelic variation in the apo epsilon gene, which codes for apolipoprotein E, and plasma lipid levels in children.

MATERIALS AND METHODS

We analyzed genotype and fasting lipid levels, including lipid particle size by nuclear magnetic resonance spectroscopy, in 515 children from 297 families.

RESULTS

Children carrying the apo epsilon2 allele (1 or 2 epsilon2 alleles; n = 45) had higher mean high-density lipoprotein (HDL) cholesterol level (49.5 +/- 13.0 vs 42.4 +/- 8.9 mg/dL) and lower mean low-density lipoprotein (LDL) cholesterol level (82.2 +/- 48.6 vs 105.9 +/- 45.0 mg/dL) compared with apo epsilon3/epsilon3 children (n = 322). Mean HDL size was larger and mean level of the atheroprotective large HDL subpopulation was higher among apo epsilon2 carriers compared with epsilon3/epsilon3 children (9.5 +/- 0.4 vs 9.3 +/-.4 nm, and 32.8 +/- 9.9 vs 27.6 +/- 8.2 mg/dL). In multivariate models adjusting for age, sex, ethnicity, family history, body mass index, and fasting triglyceride level, the apo epsilon2 allele was independently predictive of higher levels of HDL cholesterol and the large HDL subpopulation and of lower level of LDL cholesterol.

CONCLUSION

The apo epsilon2 allele is associated with an anti-atherogenic lipid pattern in children.apolipoprotein epsilon, children, cholesterol.

Apolipoprotein E4 phenotype increases non-fasting serum triglyceride concentration in infants - the STRIP study

As genetically determined apolipoprotein E (apo E) phenotypes influence serum cholesterol concentration, we analysed whether serum triglyceride values are also affected by the apo E phenotypes in infants. Non-fasting serum triglyceride values were measured in 7- and 13-month-old participants in the STRIP project, a randomised, prospective trial aimed at reducing children's exposure to known atherosclerosis risk factors (n=1062). The mean+/-S.D. non-fasting serum triglyceride concentrations in 7-month-old infants with apo E4/4 (n=36), E3/4 (n=209), E3/3 (n=412), and E2/3 (n=66) were 2. 05+/-1.24, 1.81+/-0.90, 1.63+/-0.90, and 1.71+/-0.83 mmol/l, respectively. Triglyceride concentrations were higher in infants with apo E4/4 or 3/4 than in those with apo E3/3 (P-value for difference 0.01 and 0.009, respectively). The apo E phenotype similarly influenced non-fasting serum triglyceride concentrations at the age of 13 months. The differences in serum triglyceride values in apo E4(+) infants (apo E3/4 and 4/4 infants combined) and apo E4(-) infants (apo E2/3 and 3/3 infants combined) occurred independently of the relative weight of the infant, milk type used at 7 months of age (breast milk or formula), and time elapsed from the previous meal. To conclude, apo E phenotypes regulate non-fasting serum triglyceride values in healthy infants. Apo E3/4 and apo E4/4 predispose infants to higher values than apo E3/3 phenotype, suggesting that the varepsilon4 allele may increase atherosclerosis risk also via it's effect on postprandial triglyceride metabolism.

Serum zinc, copper, insulin and lipids in Alzheimer's disease epsilon 4 apolipoprotein E allele carriers

BACKGROUND

Copper (Cu) and zinc (Zn) have been implicated in the development of Alzheimer's disease (AD) and, in this regard, Cu and Zn serum concentrations have been analysed but with inconclusive results. Serum insulin, glucose and cholesterol concentrations have been related to the apolipoprotein E genotype in non-AD populations.

DESIGN

In this study, we have analysed the relationship between serum Cu, Zn, insulin, glucose and lipid parameters (cholesterol, triglycerides, apoA and apoB apolipoproteins) in AD and AD epsilon 4 apolipoprotein E carriers by multivariate analysis using logistic regression, including the variables that showed a significance of P < 0.05 in the bivariate analysis.

RESULTS

The results obtained show that epsilon 4 apoE allele is an independent AD risk factor (OR = 6. 67, 95% CI = 2.59-17.16). In AD epsilon 4 apoE allele carriers, we found significantly higher Zn, Cu and insulin serum concentrations. Non-demented control subjects with at least one epsilon 4 apoE allele had the lowest serum insulin concentrations. There was no significant association between epsilon 4 apolipoprotein E allele and lipid parameters in the sample studied.

CONCLUSIONS

In AD we have found a significant association between higher serum Zn, Cu and insulin concentrations and the presence of an epsilon 4 apoE allele, but only greater serum Zn concentration appears to be an independent risk factor associated with the development of AD.

Molecular cloning of two new human paralogs of 85-kDa cytosolic phospholipase A2

Two new cloned human cDNAs encode paralogs of the 85-kDa cytosolic phospholipase A2 (cPLA2). We propose to call these cPLA2beta (114 kDa) and cPLA2gamma (61 kDa), giving the name cPLA2alpha to the well known 85-kDa enzyme. cPLA2beta mRNA is expressed more highly in cerebellum and pancreas and cPLA2gamma more highly in cardiac and skeletal muscle. Sequence-tagged site mapping places cPLA2beta on chromosome 15 in a region near a phosphoinositol bisphosphate phosphatase. The mRNA for cPLA2beta is spliced only at a very low level, and Northern blots in 24 tissues show exclusively the unspliced form. cPLA2beta has much lower activity on 2-arachidonoyl-phosphatidylcholine liposomes than either of the other two enzymes. Its sequence contains a histidine motif characteristic of the catalytic center of caspase proteases of the apoptotic cascade but no region characteristic of the catalytic cysteine. Sequence-tagged site mapping places cPLA2gamma on chromosome 19 near calmodulin. cPLA2gamma lacks the C2 domain, which gives cPLA2alpha its Ca2+ sensitivity, and accordingly cPLA2gamma has no dependence upon calcium, although cPLA2beta does. cPLA2gamma contains a prenyl group-binding site motif and appears to be largely membrane-bound. cPLA2alpha residues activated by phosphorylation do not appear to be well conserved in either new enzyme. In contrast, all three previously known catalytic residues, as well as one additional essential arginine, Arg-566 in cPLA2alpha, are conserved in both new enzyme sequences. Mutagenesis shows strong dependence on these residues for catalytic activity of all three enzymes.

Early blood pressure level as a mark of familial aggregation of metabolic cardiovascular risk factors--the Rio de Janeiro Study

OBJECTIVE

To investigate the familial aggregation of metabolic risk factors (RF) according to blood pressure (BP) percentile of children and adolescents.

DESIGN AND METHODS

Normal BP was established in 3906 children and adolescents in 1987. From this population two groups of target individuals were separated: group A (n = 327) with systolic and/or diastolic BP percentile > 95 and group B (n = 327) with systolic and diastolic BP percentile < or = 50. Ten years later, familial aggregation of metabolic RF was evaluated using clinical and laboratorial data from 785 individuals, divided into two groups: group 1 with 135 target individuals (BP percentile > 95), 181 parents, 100 siblings and 16 grandparents; and group 2: 106 target individuals (BP percentile < or = 50), 145 parents, 84 siblings and 18 grandparents.

RESULTS

(1) The longitudinal study 10 years later (tracking effect) showed that 34.8% of target individuals of group 1 and 90.5% of group 2 remained at the same BP percentile. (2) Comparing the two groups of target individuals, group 1 had higher weight and body mass index (BMI), systolic BP (SBP), diastolic BP (DBP), and heart rate (HR) (P < 0.001) and lower HDL (P < 0.003). (3) Comparing target individuals' and their relatives' measurements together, group 1 had higher BMI, HR, SBP, DBP (P < 0.03) and lower HDL (P < 0.001). (4) SBP and DBP showed significant correlation with all metabolic variables even when BMI was controlled in a multiple regression analysis (P < 0.04).

CONCLUSION

BP level in children and adolescents was a good marker for familial aggregation of metabolic RF, suggesting an interaction of genetic and environmental factors. Primary intervention should be carried out in early stages of life.