Routine results of an algorithm for managing the production of blood components

BACKGROUND AND OBJECTIVES

The variability in the number of donations together with a growing demand for platelet concentrates and plasma-derived medicines make us seek solutions aimed at optimizing the processing of blood. Some mathematical models to improve efficiencies in blood banking have been published. The goal of this work is to validate and evaluate an algorithm's impact in the production of blood components in the Blood and Tissues Bank of Aragon (BTBA).

MATERIALS AND METHODS

A mathematical algorithm was designed, implemented and validated through simulations with real data. It was incorporated into the fractionation area, which uses the Reveos® fractionation system (Terumo BCT) to split blood into its components. After 9 months of daily routine validation, retrospective activity data from the Blood Bank and Transfusion Services before and during the use of the algorithm were compared.

RESULTS

Using the algorithm, the outdating rate of platelet concentrates (PC) decreased by 87.8% in the blood bank. The average shelf life remaining of PC supplied to Transfusion Services increased by almost 1 day. As a consequence, the outdating rate in the Aragon Transfusion Network decreased by 33%. In addition, extra 100 litres of plasma were obtained in 9 months.

CONCLUSIONS

The algorithm improves the blood establishment's workflow and facilitates the decision-making process in whole blood processing. It resulted in a decrease in PC outdating rate, increase in PC shelf life and finally an increase in the volume of recovered plasma, leading to significant cost savings.

Sex-dependent relationship of polymorphisms in CLOCK and REV-ERBα genes with body mass index and lipid levels in children

Circadian rhythms, which are governed by a circadian clock, regulate important biological processes associated with obesity. SNPs in circadian clock genes have been linked to energy and lipid homeostasis. The aim of our study was to evaluate the associations of CLOCK and REV-ERBα SNPs with BMI and plasma lipid levels in pre-pubertal boys and girls. The study sample population comprised 1268 children aged 6-8 years. Information regarding anthropometric parameters and plasma lipid concentrations was available. Genotyping of CLOCK SNPs rs1801260, rs4580704, rs3749474, rs3736544 and rs4864548 and REV-ERBα SNPs rs2017427, rs20711570 and rs2314339 was performed by RT-PCR. The CLOCK SNPs rs3749474 and rs4864548 were significantly associated with BMI in girls but no in boys. Female carriers of the minor alleles for these SNPs presented lower BMI compared to non-carriers. A significant association of the REV-ERBα SNP rs2071570 with plasma total cholesterol, LDL-cholesterol and Apo B in males was also observed. Male AA carriers showed lower plasma levels of total cholesterol, LDL-cholesterol and Apo B levels as compared with carriers of the C allele. No significant associations between any of the studied REV-ERBα SNPs and plasma lipid levels were observed in females. In summary, CLOCK and REV-ERBα SNPs were associated with BMI and plasma lipid levels respectively in a sex-dependent manner. Our findings suggest that sex-related factors may interact with Clock genes SNPs conditioning the effects of these polymorphisms on circadian alterations.

Methylation analysis by targeted bisulfite sequencing in large for gestational age (LGA) newborns: the LARGAN cohort

BACKGROUND

In 1990, David Barker proposed that prenatal nutrition is directly linked to adult cardiovascular disease. Since then, the relationship between adult cardiovascular risk, metabolic syndrome and birth weight has been widely documented. Here, we used the TruSeq Methyl Capture EPIC platform to compare the methylation patterns in cord blood from large for gestational age (LGA) vs adequate for gestational age (AGA) newborns from the LARGAN cohort.

RESULTS

We found 1672 differentially methylated CpGs (DMCs) with a nominal p < 0.05 and 48 differentially methylated regions (DMRs) with a corrected p < 0.05 between the LGA and AGA groups. A systems biology approach identified several biological processes significantly enriched with genes in association with DMCs with FDR < 0.05, including regulation of transcription, regulation of epinephrine secretion, norepinephrine biosynthesis, receptor transactivation, forebrain regionalization and several terms related to kidney and cardiovascular development. Gene ontology analysis of the genes in association with the 48 DMRs identified several significantly enriched biological processes related to kidney development, including mesonephric duct development and nephron tubule development. Furthermore, our dataset identified several DNA methylation markers enriched in gene networks involved in biological pathways and rare diseases of the cardiovascular system, kidneys, and metabolism.

CONCLUSIONS

Our study identified several DMCs/DMRs in association with fetal overgrowth. The use of cord blood as a material for the identification of DNA methylation biomarkers gives us the possibility to perform follow-up studies on the same patients as they grow. These studies will not only help us understand how the methylome responds to continuum postnatal growth but also link early alterations of the DNA methylome with later clinical markers of growth and metabolic fitness.

Functional foods and nutraceuticals in the treatment of hypercholesterolemia: Statement of the Spanish Society of Arteriosclerosis 2023

In the management of hypercholesterolemia, besides advising a healthy, plant-based diet, it may be useful to recommend functional foods or nutraceutical with cholesterol-lowering properties. Given the progressive increase in the number of these products and their rising use by the population, the Spanish Society of Arteriosclerosis (SEA) has considered it appropriate to review the available information, select the results of the scientifically more robust studies and take a position on their usefulness, to recommend to health professionals and the general population their potential utility in terms of efficacy and their possible benefits and limitations. The following clinical scenarios have been identified in which these products could be used and will be analyzed in more detail in this document: (1) Hypolipidemic treatment in subjects with statin intolerance. (2) Hypolipidemic treatment «a la carte» in individuals in primary prevention. (3) Long-term cardiovascular prevention in individuals with no indication for lipid-lowering therapy. (4) Patients with optimized lipid-lowering treatment who do not achieve therapeutic objectives.

Relationship between eating habits, sleep patterns and physical activity and the degree of obesity in children and adolescents

INTRODUCTION

Childhood obesity is an extremely prevalent pathology and, in order to be able to address it, it is necessary to understand the factors that influence on its genesis and maintenance. We hypothesise that the timing of meals and sleep, the regularity of these throughout the week and a sedentary lifestyle influence the degree of obesity.

MATERIAL AND METHODS

We included children and adolescents with obesity who attended a first check-up visit at the Childhood Obesity Unit between January 2018 and February 2020. The data were obtained from a questionnaire on food (36-h intake, frequency of consumption, eating times and habits) and sleep.

RESULTS

The degree of obesity was influenced to a greater extent by later meal times and the distribution of calories throughout the day (less at breakfast, more at dinner) than by the total number of calories ingested. In addition, a lower consumption of vegetables was related to a higher degree of obesity. The difference between the hours of sleep at weekends and on weekdays correlated positively with a higher degree of obesity. Finally, the anthropometric data correlated negatively with the number of hours of physical activity. Almost half of the children did not exercise after school.

CONCLUSION

In the approach to childhood obesity, it is necessary to include recommendations on the regularity of meal and sleep times, as well as the distribution of calories throughout the day. Additionally, it is necessary to encourage the practice of physical exercise.

Hemorrhagic cystitis following allogeneic hematopoietic stem cell transplantation: experience in a pediatric oncological institution

OBJECTIVE

To analyze the risk factors associated with hemorrhagic cystitis (HC) severity and the treatment strategies available in HC patients following allogeneic hematopoietic stem cell transplantation (AHSCT).

MATERIALS AND METHODS

A retrospective study of medical records was carried out. Patients with HC following AHSCT treated from 2017 to 2021 were divided into two groups according to severity -mild and severe. Demographic data, disease-specific characteristics, urological sequelae, and overall mortality were compared between both groups. The hospital's protocol was used for patient management.

RESULTS

33 episodes of HC were collected in 27 patients, 72.7% of whom were male. HC incidence following AHSCT was 23.4% (33/141). 51.5% of HCs were severe (grades III-IV). Severe graft host disease (GHD) (grades III-IV) and thrombopenia at HC onset were associated with severe HC (p= 0.043 and p= 0.039, respectively). This group had longer hematuria times (p< 0.001) and required more platelet transfusions (p= 0.003). In addition, 70.6% required bladder catheterization, but only 1 case needed percutaneous cystostomy. None of the patients with mild HC required catheterization. No differences were found in terms of urological sequelae or overall mortality.

CONCLUSIONS

Severe HC could be predicted thanks to the presence of severe GHD or thrombopenia at HC onset. Severe HC can be managed with bladder catheterization in most of these patients. A standardized protocol may help reduce the need for invasive procedures in patients with mild HC.

Leptin Concentrations Determine the Association between High-Sensitivity C-Reactive Protein Levels and Body Mass Index in Prepubertal Children

Obesity is associated with the presence of low-grade inflammation even during childhood. The dysregulation in the secretion of adipokines, such as leptin, which occurs in obesity states, could be associated with an increase in inflammatory factors already at an early age. In this cross-sectional study, we aimed to investigate the role of leptin levels in the association between body mass index (BMI) and high-sensitivity C-reactive protein (hs-CRP) in healthy schoolchildren. Leptin and hs-CRP levels were analyzed in two pediatric cohorts comprising 684 prepubertal children and 763 adolescents. hs-CRP concentrations correlated significantly with BMI and leptin levels in prepubertal males and females as well as in adolescents. However, after adjusting for leptin concentration, no significant correlation was observed between hs-CRP and BMI in prepubertal children, while the correlations remained significant in adolescents. The same differences were observed when analyzed BMI according to hs-CRP tertile after adjusting for leptin; mean BMI was not significantly different between hs-CRP tertile in prepubertal children but was significantly different in adolescents. In conclusion, the fact that leptin concentrations determine the association of BMI with hs-CRP levels in prepubertal children, but not in adolescents, suggests a role for leptin in low-grade inflammation at early ages, while other factors seem to contribute to hs-CRP levels later in life.

Response to Melatonin Treatment in Children With Autism spectrum Disorder and Relationship to Sleep Parameters and Melatonin Levels

Melatonin is one of the most used pharmacologic treatments for sleep problems in autism spectrum disorder, though its relationship with circadian and sleep parameters is still not well stablished. A naturalistic study was conducted in children with autism spectrum disorder, previously drug-naïve, before and after treatment with immediate-release melatonin. Circadian rhythms and sleep parameters were studied using an ambulatory circadian-monitoring device, and saliva samples were collected enabling determination of dim light melatonin onset. Twenty-six children with autism spectrum disorder (age 10.50  ±  2.91) were included. Immediate-release melatonin modified circadian rhythm as indicated by wrist skin temperature, showing an increase at night. A positive correlation was found between time of peak melatonin and sleep efficiency improvement values. Sleep-onset latency and efficiency improved with immediate-release melatonin. Immediate-release melatonin could be an effective treatment to improve sleep onset and restore a typical pattern of wrist temperature, which appears to be lost in autism spectrum disorder.

Prevalence and risk factors associated with different comorbidities in obese children and adolescents

INTRODUCTION

Different obesity-related comorbidities already present in childhood, such as: vitamin D deficiency, impaired carbohydrate metabolism, dyslipidaemia, arterial hypertension and non-alcoholic steatohepatitis. In this study, we aim to analyse the prevalence of comorbidities and to determine the predictive factors that affect these comorbidities.

MATERIAL AND METHODS

Anthropometric, demographic and biochemical variables were collected from obese patients between six and 18 years of age. Subsequently, a statistical analysis was performed to describe the characteristics of the patients and the prevalence of comorbidities, as well as their predictive factors.

RESULTS

A total of 158 obese children (76 boys and 82 girls) with a mean age at diagnosis of 12.48 years and a BMI Z-score of +3.24 SDS were included. The most prevalent comorbidities were vitamin D deficiency (64.2%), insulin resistance (45.1%), dyslipidaemia (32.2%), hyperuricaemia (18.5%) and arterial hypertension (15%). Age, BMI Z-score, percentage of fat mass and male sex have been found to be predictors of these comorbidities.

CONCLUSION

Obese children and adolescents have a high prevalence of comorbidities. Once the diagnosis of obesity has been established, it would be very useful to identify early those patients with a higher risk of comorbidities, knowing their relationship with sex, age, BMI Z-score, percentage of fat mass and pubertal stage.

Sex-Dependent Mediation of Leptin in the Association of Perilipin Polymorphisms with BMI and Plasma Lipid Levels in Children

Variations in the perilipin (PLIN) gene have been suggested to be associated with obesity and its related alterations, but a different nutritional status seems to contribute to differences in these associations. In our study, we examined the association of several polymorphisms at the PLIN locus with obesity and lipid profile in children, and then analyzed the mediation of plasma leptin levels on these associations. The single-nucleotide polymorphisms (SNPs) rs894160, rs1052700, and rs2304795 in PLIN1, and rs35568725 in PLIN2, were analyzed by RT-PCR in 1264 children aged 6–8 years. Our results showed a contrasting association of PLIN1 rs1052700 with apolipoprotein (Apo) A-I levels in boys and girls, with genotype TT carriers showing significantly higher Apo A-I levels in boys and significantly lower Apo A-I levels in girls. Significant associations of the SNP PLIN2 rs35568725 with high-density lipoprotein cholesterol (HDL-cholesterol), Apo A-I, and non-esterified fatty acids (NEFA) were observed in boys but not in girls. The associations of the SNPs studied with body mass index (BMI), NEFA, and Apo A-I in boys and girls were different depending on leptin concentration. In conclusion, we describe the mediation of plasma leptin levels in the association of SNPs in PLIN1 and PLIN2 with BMI, Apo A-I, and NEFA. Different leptin levels by sex may contribute to explain the sex-dependent association of the PLIN SNPs with these variables.

Melatonin Rhythm and Its Relation to Sleep and Circadian Parameters in Children and Adolescents With Autism Spectrum Disorder

Introduction

Sleep problems are prevalent among individuals with autism spectrum disorder (ASD), and a role has been attributed to melatonin in this multifactorial comorbidity.

Methods

A cross-sectional study was conducted on 41 autistic children and adolescents (9.9 ± 3.02) and 24 children and adolescents with a normal intellectual function (8.42 ± 2.43) were used as controls. Subjects were matched for sex, body mass index, and pubertal stage, and all were drug-naive. Circadian and sleep parameters were studied using an ambulatory circadian monitoring (ACM) device, and saliva samples were collected around the onset of sleep to determine dim light melatonin onset (DLMO).

Results

Prepubertal individuals with ASD presented later DLMO and an earlier decline in melatonin during adolescence. A relationship was found between melatonin and both sleep and circadian parameters. Participants and controls with later DLMOs were more likely to have delayed sleep onset times. In the ASD group, subjects with the later daytime midpoint of temperature had a later DLMO. Later melatonin peak time and DLMO time were related to lower general motor activity and lower stability of its rhythms.

Conclusion

The melatonin secretion pattern was different in individuals with ASD, and it showed a relationship with sleep and circadian parameters. Alterations in DLMO have not been previously reported in ASD with the exception of more variable DLMO timing; however, high variability in the study design and sample characteristics prevents direct comparison. The ACM device enabled the measurement of circadian rhythm, a scarcely described parameter in autistic children. When studied in combination with other measures such as melatonin, ACM can offer further knowledge on sleep problems in ASD.

Association of ACE2 Polymorphisms and Derived Haplotypes With Obesity and Hyperlipidemia in Female Spanish Adolescents

Background

In the cardiovascular (CV) system, overactivation of the angiotensin converting enzyme (ACE) may trigger deleterious responses derived from angiotensin (Ang)-II, which can be attenuated by stimulation of ACE2 and subsequent Ang-(1-7) metabolite. However, ACE2 exhibits a high degree of genetic polymorphism that may affect its structure and stability, interfering with these cardioprotective actions. The aim of this study was to analyse the relationship of ACE2 polymorphisms with cardiovascular risk factors in children.

Methodology

Five ACE2-single nucleotide polymorphisms (SNP), rs4646188, rs2158083, rs233575, rs879922, and rs2074192, previously related to CV risk factors, were analyzed in a representative sample of 12–16-year-old children and tested for their potential association with anthropometric parameters, insulin levels and the lipid profile.

Results

Girls (N = 461) exhibited lower rates of overweight, obesity, blood pressure, and glycemia than boys (N = 412), though increased plasma lipids. The triglycerides (TG)/HDL-C ratio was, however, lower in females. Interestingly, only in girls, the occurrence of overweight/obesity was associated with the SNPs rs879922 [OR 1.67 (1.02–2.75)], rs233575 [OR 1.98 (1.21- 3.22)] and rs2158083 [OR 1.67 (1.04–2.68)]. Also, TG levels were linked to the rs879922, rs233575, and rs2158083 SNPs, and the TG/HDL-C ratio was associated with rs879922 and rs233575. Levels of TC and LDL-C were associated with rs2074192 and rs2158083. Furthermore, the established cut-off level for TG ≥ 90 mg/dL was related to rs879922 [OR 1.78 (1.06–2.96)], rs2158083 [OR 1.75 (1.08–2.82)], and rs233575 [OR 1.62 (1.00–2.61)]. The cut-off level for TC ≥ 170 mg/dL was associated with rs2074192 OR 1.54 (1.04–2.28) and rs2158083 [OR 1.53 (1.04–2.25)]. Additionally, the haplotype (C-G-C) derived from rs879922-rs2158083-rs233575 was related to higher prevalence of overweight/obesity and TG elevation.

Conclusion

The expression and activity of ACE2 may be essential for CV homeostasis. Interestingly, the ACE2-SNPs rs879922, rs233575, rs2158083 and rs2074192, and the haplotype (C-G-C) of the three former could induce vulnerability to obesity and hyperlipidemia in women. Thus, these SNPs might be used as predictive biomarkers for CV diseases and as molecular targets for CV therapy.

Sex-dependent relationship of C-reactive protein levels with HDL-cholesterol and HDL-phospholipid concentrations in children

Obesity has been consistently associated with inflammation but the influence of HDL on this association remains under study. Our study analyzes the influence of obesity-related parameters in the relationship of high-sensitivity C-reactive protein (hs-CRP) with HDL-cholesterol and HDL-phospholipid in male and female adolescents. The study sample population comprised 350 males and 401 females aged 12 to 16 years. Information regarding anthropometric parameters, HDL-cholesterol, HDL-phospholipid, adiponectin, leptin, insulin, and hs-CRP concentrations was available. hs-CRP levels were inversely related to HDL-cholesterol and HDL-phospholipid in males but not in females, and were positively related to leptin concentrations in both sexes but were not related to adiponectin levels. In regression analyses, HDL-phospholipid and leptin appeared significantly associated to hs-CRP in males in a model explaining 14.3% of hs-CRP variation. In females, only leptin appeared related to hs-CRP concentrations. After adjusting by leptin and adiponectin, males in the highest hs-CRP tertile showed significantly lower levels of HDL-cholesterol and HDL-phospholipid than those in tertiles 1 and 2, while no significant differences in HDL-cholesterol and HDL-phospholipid concentrations by hs-CRP tertile were observed in females. In summary, high hs-CRP levels were associated with lower plasma HDL-cholesterol and HDL-phospholipid concentrations in male adolescents irrespective of adipokines, while in females, HDL-related parameters are not associated with hs-CRP concentrations.

PPARγ2 Pro12Ala Polymorphism is Associated in Children With Traits Related to Susceptibility to Type 2 Diabetes

Peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-activated nuclear receptor that regulates glucose and lipid metabolism. Pharmacological activators of PPARγ are being used as a treatment of obesity related disorders such as dyslipidaemia and type 2 diabetes, but questions remain open regarding the effects of PPARγ on traits related to the development of type 2 diabetes. In our study, we have analyzed the relationship of the common variant Pro12Ala in the human PPARγ2 gene with the presence of obesity and with insulin, HOMA and lipid profile in a representative sample of 6-to 8-year-old children free from the confounding factors associated with adults. We found that Ala12Ala genotype was significantly more frequent in females with obesity than in those without obesity, with Ala12Ala carriers having significantly higher weight and body mass index (BMI), however the association disappeared when adjusting by leptin concentrations. The Ala12Ala genotype was associated with significantly higher HDL-cholesterol and apoA-I levels in males but not in females, independently of BMI. In a recessive model, in females, leptin levels appeared higher in Ala12Ala carriers. Although no apparent differences were observed in any sex when analyzing insulin levels and HOMA among genotypes without adjusting, lower insulin levels and lower HOMA appeared associated with Ala12Ala carriers when adjusting for BMI and leptin levels. In summary, our data showed that leptin seems to be having an effect on the association between the PPARγ2 Pro12Ala and BMI. Besides, after controlling for BMI and leptin, a protective effect of the Ala12Ala variant of the PPARγ2 Pro12Ala polymorphism on insulin sensitivity is evident already in prepubertal children.

Improvement of Blood Processing and Safety by Automation and Pathogen Reduction Technology

Introduction

The objective of the present study was to describe the experience of the Blood and Tissues Bank of Aragon with the Reveos® Automated Blood Processing System and Mirasol® Pathogen Reduction Technology (PRT) System, comparing retrospectively routine quality data obtained in two different observation periods.

Methods

Comparing quality data encompassing 6,525 blood components from the period 2007-2012, when the semi-automated buffy coat method was used in routine, with 6,553 quality data from the period 2014-2019, when the Reveos system and subsequently the Mirasol system were implemented in routine.

Results

Moving from buffy coat to Reveos led to decreased discard rates of whole blood units (1.2 to 0.1%), increased hemoglobin content (48.1 ± 7.6 to 55.4 ± 6.6 g/unit), and hematocrit (58.9 ± 6.5% to 60.0 ± 4.9%) in red blood cell concentrates. Platelet concentrates (PCs) in both periods had similar yields (3.5 ×10¹¹). Whereas in the earlier period, PCs resulted from pooling 5 buffy coats, in the second period 25% of PCs were prepared from 4 interim platelet units. The mean level of factor VIII in plasma was significantly higher with Reveos (92.8 vs. 97.3 IU). Mirasol PRT treatment of PCs reduced expiry rates to 1.2% in 2019. One septic transmission was reported with a non-PRT treated PCs, but none with PRT-treated PCs.

Conclusion

Automation contributed to standardization, efficiency, and improvement of blood processing. Released resources enabled the effortless implementation of PRT. The combination of both technologies guaranteed the self-sufficiency and improvement of blood safety.

Leptin Concentration, Obesity, and Plasma Non-esterified Fatty Acid Levels in Children

The association between obesity and higher non-esterified fatty acid (NEFA) levels has been established in adults. In contrast, lower NEFA levels have been described in children with obesity although the reason behind this association remains unclear. Leptin, which regulates body weight and plays a role in lipolysis, could be involved in this relationship. We evaluated the influence of leptin in the association between obesity and NEFA concentrations in children, analyzing two cohorts including 684 6- to 8-year-olds and 836 12- to 16-year-old children, respectively. After adjusting by leptin, insulin levels remained significantly higher in adolescents with obesity as compared with levels in those without obesity. However, insulin levels showed no differences between prepubertal children with and without obesity. The significantly lower NEFA concentrations observed in 6- to 8-year-old girls with obesity disappeared when comparing NEFA levels between girls with and without obesity after adjusting by leptin. We report an influence of leptin levels on the association between obesity and insulin and NEFA in young children that is not observed in adolescents. Our findings add information about factors that may contribute to explain the lower NEFA levels described in prepubertal children with obesity.

Sex steroid hormones, leptin, and high-sensitivity C-reactive protein levels in adolescents

BACKGROUND

The association of sex hormones with C-reactive protein (CRP) levels has been reported. However, this association remains unexplored in children in whom important anthropometric and hormonal changes are taking place.

OBJECTIVES

To analyze the association between high-sensitivity CRP (hs-CRP) and testosterone, estradiol and sex hormone-binding globulin (SHBG) levels in a population-based sample of adolescents, and to evaluate the influence of leptin levels on this association.

MATERIALS AND METHODS

The sample population of this cross-sectional study was comprised of 338 male and 385 female adolescents, aged 12-16 years. Information on anthropometric variables, hormone, leptin, and hs-CRP levels was available.

RESULTS

In male adolescents in our study, higher age is significantly associated with higher testosterone levels and with lower leptin and SHBG concentrations across the range of age studied. No significant changes in leptin and SHBG levels by age are observed in females. In males, leptin correlates negatively with testosterone levels (-0.263, p < 0.001), showing a stronger correlation after adjusting by body mass index (BMI) (-0.424, p < 0.001). A significant correlation between hs-CRP and testosterone levels is observed in males after adjusting by BMI, but the correlation disappears after adjusting by leptin. No association between testosterone and hs-CRP was observed in females. The negative association between hs-CRP levels and SHBG remains significant after adjusting by leptin in both sexes but disappears in males after adjusting by BMI.

CONCLUSION

The negative association between hs-CRP and testosterone concentrations observed in 12- to 16-year-old males seems to be related to leptin levels which are closely negatively related to testosterone levels in males independently of BMI.

Opposite Association of Adropin Concentrations with Obesity in Prepubertal Children Compared with Adolescents

OBJECTIVE

The aim of this study was to evaluate the association between obesity and plasma adropin levels in two cohorts of children at two different ages.

METHODS

Adropin concentrations were measured in 71 prepubertal and 41 pubertal children with obesity and their age- and sex-matched normal weight counterparts (69 prepubertal and 42 pubertal children). Information was available in these children on insulin levels, lipid profile, and leptin levels. Adropin levels were measured by using a commercial enzyme-linked immunosorbent assay kit.

RESULTS

Plasma adropin levels were significantly higher (P < 0.001) in prepubertal than pubertal children. Adropin concentrations were significantly higher (P < 0.001) in prepubertal girls than in prepubertal boys but significantly lower (P < 0.001) in pubertal girls than in pubertal boys. Prepubertal boys and girls with obesity had significantly higher adropin levels (P < 0.001) than their normal weight counterparts. In contrast, no differences in adropin levels were observed in pubertal children when comparing children with obesity and normal weight boys and girls.

CONCLUSIONS

An important decrease in adropin levels in pubertal children compared with prepubertal children was shown as well as a differing association of adropin with obesity depending on age. These findings suggest a possible relationship between adropin levels and centrally regulated sex hormones involved in pubertal development.

Children with type 1 diabetes have elevated high-sensitivity C-reactive protein compared with a control group

INTRODUCTION

Our objective was to compare high-sensitivity C-reactive protein (hsCRP) levels in children with type 1 diabetes, healthy controls, and children with obesity. Additionally, we aimed to analyze the association between hsCRP levels and glycemic control measured by glycohemoglobin A (HbA1c) and anthropometric and biochemical variables.

RESEARCH DESIGN AND METHODS

We conducted a non-randomized descriptive study of children with type 1 diabetes matched for sex and age with a control group and group with obesity. We recorded anthropometric parameters and studied variables related to diabetes, blood pressure, lipid profile, and HbA1c. hsCRP was measured by ELISA.

RESULTS

We included 49 children with type 1 diabetes, 46 controls, and 40 children with obesity. hsCRP levels were significantly higher in the group with type 1 diabetes compared with controls and nearly significantly lower than in the group comprising children with obesity. We found no correlation between hsCRP and HbA1c and characteristics of type 1 diabetes with the exception of albumin to creatinine ratio. Statistically significant association was found between hsCRP and body mass index (BMI) and waist circumference Z-score.

CONCLUSIONS

The higher hsCRP levels observed in children with type 1 diabetes compared with a control group with a similar BMI suggest a basal inflammatory state that could increase cardiovascular risk. The main factors related to hsCRP are BMI and waist circumference, so obesity prevention should be a priority when performing follow-up in children with type 1 diabetes.

Phenotype of haptoglobin and presence of subclinical vascular disease: Population study

INTRODUCTION AND OBJECTIVES

Haptoglobin is a protein involved in the protection against oxidative damage caused by iron in haemoglobin. This protein is polymorphic, with 3 isomorphs prevalent in the population. The carriers of the Hp2-2 isoform have a lower antioxidant capacity and, in the population with diabetes, an increased risk of subclinical vascular disease and cardiovascular complications. The objective of this study was to evaluate whether this isomorphy is associated with an increased risk of carotid arteriosclerosis in subjects with and without diabetes, and free of cardiovascular disease.

PATIENTS AND METHODS

A study was conducted in a population between 45 and 74years of age, randomly selected from the northwest area of Madrid. The participants were characterised in terms of their glycaemic status by oral glucose overload and the determination of the concentration of Hb1Ac. The haptoglobin phenotypes in all of them were determined by means of an immunoenzymatic assay, and the presence of carotid arteriosclerosis by ultrasound.

RESULTS

Of the 1,256 participants included in the present analysis (mean age 61.6±6years, 41.8% males), the distribution of the isoforms of haptoglobin was as follows: Hp1-1: 13.3%, Hp1-2: 48.5%, and Hp2-2: 38.2%. In comparison with subjects Hp1-1 and Hp1-2, those with the Hp2-2 phenotype had a higher prevalence of dyslipidaemia (53.3% vs 43%; P<.0001) and arterial hypertension (39.2% vs. 32.2%, P=.012), and they more frequently received treatment with statins (31.5% vs 21.6%, P<.0001), and with antihypertensive agents (38.4% vs 30.8%, P=.006). The carriers of the Hp2-2 isoform had a higher prevalence of carotid plaques (OR: 1.35, 95%CI: 1.07-1.69, P=.011), with no differences in that prevalence as regards the glycaemic status. There were no differences in the intima-media thickness between the different phenotypes. The relationship of the Hp2-2 phenotype with the presence of plaques in the carotid was independent of age, gender, presence of risk factors (dyslipidaemia, hypertension and diabetes), the concentration of LDL-cholesterol, C-reactive protein and uric acid, blood pressure, and treatment with statins, and hypertensive drugs (OR: 1.31, 95%CI 1.01-1.70, P=.044).

CONCLUSION

Subjects with the Hp2-2 phenotype of haptoglobin have a higher prevalence of carotid arteriosclerosis, which is independent of the presence of other cardiovascular risk factors and their glycaemic status.

Sex-specific association of plasma nesfatin-1 concentrations with obesity in children

BACKGROUND

Nesfatin-1, an anorexigenic peptide, has been associated with food intake and thermogenesis, with discordant findings in humans and scarce studies in children to date.

OBJECTIVES

The aim of this study was to analyze the relationship of obesity with nesfatin-1 levels in two cohorts of children.

METHODS

Plasma nesfatin-1 concentrations were analyzed in 6- to 9-year-olds (n = 140) and 12- to 16-year-old children (n = 96), including children with obesity and their sex- and age-matched normal-weight counterparts. Anthropometric measurements were assessed. Cholesterol and triglycerides were determined enzymatically, insulin concentrations were measured by radioimmunoassay using a commercial kit and nesfatin-1, leptin and hs-CRP concentrations were determined using commercial ELISA kits.

RESULTS

Nesfatin-1 concentrations were significantly lower in younger (P = .001) and older (P = .009) girls with obesity than in their normal-weight counterparts, without showing significant differences in boys. Nesfatin-1 showed a negative significant (P < .010) correlation with weight and BMI in girls but not in boys. A significant positive correlation of nesfatin-1 levels with insulin, HOMA, and leptin levels appears in girls after adjusting by age and BMI. A significant positive correlation (P = .003) was observed between nesfatin-1 and fat mass in older children.

CONCLUSIONS

Our study shows lower concentrations of nesfatin-1 related to obesity in girls but not in boys at two different ages. The existence of a sex-specific association between nesfatin-1 concentrations and presence of obesity highlights the need of an analysis by gender of the relationship of nesfatin-1 with obesity.

Customized Dietary Intervention Avoids Unintentional Weight Loss and Modulates Circulating miRNAs Footprint in Huntington's Disease

SCOPE

Huntington's disease (HD) is a rare progressive neurodegenerative disorder of genetic origin, with no definitive treatment. Unintentional weight loss (UWL) is a clinical feature of symptomatic HD subjects. To prevent UWL, a customized HD diet is designed and its impact on plasma miRNA HD footprint and neurological parameters is examined.

METHODS AND RESULTS

Eleven participants are included, BMI ≤ 18 kg m^-2 or UWL of 5% in 6 months or 10% in a year. Diet design is based on nutritional surveys and interviews of participants and caregivers and on published literature review. Twelve-month dietary intervention, with follow-up every 3 months, induces high diet adherence, which manages to curb UWL in all participants (73% gained weight). Noticeable increases in fat mass and leptin levels are obtained. The results also show significant decrease in the expression of 19 miRNAs, which are previously reported to be upregulated in HD-patients versus healthy controls: revealing hsa-miR-338-3p, hsa-miR-128-3p, hsa-miR-23a-3p, and hsa-miR-24-3p as potential HD-biomarkers. The diminished expression of hsa-miR-100-5p reflects the general maintenance of the functional status. Cognitive status is improved in six of 11 participants, while only three present better motor-score values.

CONCLUSION

A customized HD-diet prevents UWL and modified miRNAs HD-footprint. The normalization of miRNA values suggests its potentially use as HD-biomarkers.

Relationship of the Adherence to a Mediterranean Diet and Its Main Components with CRP Levels in the Spanish Population

Background: Adherence to a Mediterranean diet seems to be inversely associated with C-reactive protein (CRP) concentration. A 14-point Mediterranean Diet Adherence Screener (MEDAS) has been developed to assess dietary compliance. Objective: The aim of this study was to assess whether each of the MEDAS questions as well as their final score were associated with the levels of CRP in general Spanish population.

METHODS

Cross-sectional analysis of 1411 subjects (mean age 61 years, 43.0% males) randomly selected from the general population. CRP levels were determined by a commercial ELISA kit. Adherence to the Mediterranean diet was measured by the 14-point MEDAS. Results: There was an inverse correlation between adherence to the Mediterranean diet and the CRP concentration, even after adjusting by age, gender, hypertension, metabolic syndrome, body mass index, statin treatment and hypertension treatment (p = 0.041). Subjects who consume ≥2 servings of vegetables per day (p = 0.003), ≥3 pieces of fruit per day (p = 0.003), ≥1 serving of butter, margarine, or cream per day (p = 0.041) or ≥3 servings of fish/seafood per week (p = 0.058) had significantly lower levels of CRP. Conclusions: Adherence to a Mediterranean-type diet measured by a simple questionnaire is associated with lower CRP concentration. However, this association seems to be particularly related to a higher consumption of vegetables, fruits, dairy products, and fish.

Vegetable and Fruit Intakes Are Associated with hs-CRP Levels in Pre-Pubertal Girls

The influence of diet on inflammation in children remains unclear. We aimed to analyze the influence of diet on high-sensitivity C-reactive protein (hs-CRP) levels in a pre-pubertal population free of other influences that may affect hs-CRP levels. We determined hs-CRP levels in 571 six- to eight-year-old children using an hs-CRP ELISA kit. Information on food and nutrient intake was obtained through a food-frequency questionnaire. Overall dietary quality was assessed using the Healthy Eating Index (HEI). We found that girls in the highest tertile of hs-CRP levels had a higher intake of saturated fatty acid, and lower intakes of fiber and vitamin E and a lower HEI score when compared to those in tertiles 1 and 2. We also observed a significant decrease in fruit and vegetable intakes by hs-CRP tertile. Factor analysis showed that a dietary pattern that was loaded most strongly with vegetable, fruit, fiber and vitamin A and E intakes correlated negatively (−0.132, p < 0.05) with hs-CRP. No such association was found in boys. In conclusion, our data show that girls with a poorer quality diet show higher hs-CRP levels already at a pre-pubertal age.

Sex-related differences in the association of ghrelin levels with obesity in adolescents

BACKGROUND

The utility of ghrelin as a biomarker may be different depending on gender. The aim of this study was to assess ghrelin levels in a population-based sample of adolescents, and to evaluate their association with obesity and obesity-related parameters depending on sex.

METHODS

The studied population included 601 randomly selected 14-to 16-year-old children. Anthropometrical data were measured and body mass index (BMI) and waist to hip ratio calculated. Body composition was assessed using an impedance body composition analyzer. Total serum ghrelin levels were determined using a multiplexed bead immunoassay. Serum leptin and adiponectin levels were determined by ELISA and insulin by RIA.

RESULTS

Ghrelin levels were significantly higher in girls than in boys. Serum ghrelin concentrations were significantly lower (p<0.01) in obese than in normal weight (NW) girls, but showed no differences by weight category in boys. Ghrelin showed a significant negative relationship with waist circumference (WC), waist to hip ratio and fat mass (p<0.05) in both genders, and with weight and BMI (p<0.01) in girls, and insulin (p<0.01) and HOMA (p<0.05) in boys. Ghrelin also correlated negatively with leptin levels in girls (p<0.01).

CONCLUSIONS

Our study describes serum ghrelin levels in adolescents, showing a sexual dimorphism in ghrelin levels in these 14-to 16-year-old children, and a different association of ghrelin levels with obesity by gender that suggests a different appetite and energy expenditure control depending on sex at this age.

Relationship between polymorphisms in the CRP, LEP and LEPR genes and high sensitivity C-reactive protein levels in Spanish children

Background:

We investigated the association of single nucleotide polymorphisms (SNPs) in the C-reactive protein (

Methods:

We measured hs-CRP levels in 646 6–8-year-old and 707 12–16-year-old children using a high-sensitivity C-Reactive Protein ELISA kit. Four SNPs in the

Results:

The four CRP SNPs studied were significantly (p<0.05) associated with hs-CRP levels in both cohorts. Furthermore, two common CRP haplotypes (constructed using the SNPs in order: rs1205, rs1130864, rs1800947, rs2794521) ACGA and GCGG were associated with significantly lower CRP levels (p<0.05) at both ages. The LEPR SNPs rs1137100 (K109R) and rs1137101 (Q223R), and LEP SNP rs7799039 (G2548A) were also associated to hs-CRP levels (p<0.05) in both cohorts.

Conclusions:

hs-CRP levels in healthy Spanish children, besides being associated to common polymorphisms in the

High-Sensitivity C-Reactive Protein and Leptin Levels Related to Body Mass Index Changes Throughout Childhood

OBJECTIVES

To analyze the association between high-sensitivity C-reactive protein (hs-CRP) levels and cardiovascular risk factors in healthy school children, and to evaluate whether changes in body mass index (BMI) category throughout childhood affect hs-CRP levels.

STUDY DESIGN

We measured serum hs-CRP levels, lipid profile, insulin levels, and leptin levels in 683 prepubertal children and 748 adolescents. A total of 272 children participated in the study in both cohorts, prepubertal (baseline; age 6-8 years) and adolescents (follow-up; age 12-16 years).

RESULTS

Compared with their normal weight (NW) counterparts, hs-CRP levels were significantly higher in obese and overweight (OW) adolescents and obese prepubertal children. The highest hs-CRP levels were seen in children who were OW at baseline and at follow-up, and the lowest levels in those who transitioned from OW at baseline to NW at follow-up. High-density lipoprotein cholesterol and apolipoprotein A-I levels decreased across the hs-CRP tertile in both prepubertal children and adolescents, with significant differences (P < .001) in concentrations between the highest and lowest tertiles in 6- to 8-year-old boys and girls and in 12- to 16-year-old boys. The hs-CRP levels were also significantly associated with leptin levels in both prepubertal children and adolescents, with a significant increase across hs-CRP tertiles (P < .001).

CONCLUSIONS

The shift from OW to NW throughout childhood is associated with a decrease in hs-CRP level to below that observed in children who maintain NW throughout childhood. Leptin levels were strongly associated with hs-CRP levels in our population independent of BMI. Our findings suggest that an obesity-related chronic inflammatory state may be reversible by improving weight status.

High Prepubertal Leptin Levels Are Associated With Earlier Menarcheal Age

PURPOSE

Given the interplay between metabolic status and the reproductive system, factors governing energy homeostasis could influence the timing of pubertal onset. The aim of this longitudinal study was to determine the influence of metabolic peptides associated to adiposity on menarcheal age.

METHODS

The sample population included 168 girls. Anthropometric and biochemical variables were measured at a prepubertal baseline (6-8 years old) and 7 years later. Leptin and adiponectin levels were determined by Enzyme-Linked ImmunoSorbent Assay, insulin by radioimmunoassay and ghrelin by a multiplexed bead immunoassay.

RESULTS

Adjusted for body mass index, Spearman correlation analysis revealed a significant negative association between prepubertal leptin levels and menarche. The highest prepubertal leptin levels were observed in overweight girls with the earliest menarche. Menarcheal age was significantly associated with variation of adiponectin levels between both baseline and follow-up. Multiple regression analysis showed that prepubertal leptin was the only significant contributing factor, predicting 15.3% of variation in menarcheal age.

CONCLUSIONS

High leptin levels in prepubertal girls are associated with earlier menarcheal age, independent of body mass index. However, the relationship of ghrelin, insulin, or adiponectin levels with menarcheal age is not evident in our population.

Earlier menarcheal age in Spanish girls is related with an increase in body mass index between pre-pubertal school age and adolescence

BACKGROUND

Higher body mass index (BMI) has been associated with earlier pubertal development.

OBJECTIVE

The aim of this longitudinal study was to determine menarcheal age in a Spanish cohort and to assess its association with anthropometric variables at birth, childhood and adolescence. We also analyse whether the tracking of weight between different ages could affect the timing of menarche.

METHODS

The sample population included 195 randomly selected 6-8-year-old girls who participated in the baseline of the Four Provinces Study and in the follow-up of this study at 13-16 years old. Anthropometrical variables were measured and BMI and BMI z-score were calculated. Information regarding birth weight and menarche was obtained by means of self-report questionnaire.

RESULTS

Correlation analysis showed a significant negative association of age at menarche with weight, BMI and BMI z-score in the baseline and follow-up groups but not with weight at birth. Fat mass at adolescence is related to a significantly earlier menarcheal age. When comparing weight categories, earliest menarcheal age is associated with an increase of BMI between 6-8-year-old and 13-16-year-old girls.

CONCLUSION

In our study, high weight in girls is associated with the earliest age at menarche. This becomes a major influence when weight gain occurs between pre-pubertal school age and adolescence.

Relationship of high leptin levels with an adverse lipid and insulin profile in 6-8 year-old children in Spain

BACKGROUND AND AIMS

Leptin, an adipokine elevated in obesity, may be related to an adverse cardiovascular risk profile in childhood. However, evidence for this relationship in pre-pubertal children is scarce. We aimed to analyze the relationship between leptin levels and lipid and insulin profiles in Spanish children.

METHODS AND RESULTS

Our population-based sample included 389 males and 369 females aged 6-8 years. Lipid levels were determined by standard methods, insulin by radioimmunoassay and leptin by sandwich ELISA. Leptin levels were higher in girls (8.6 ng/ml) than boys (4.7 ng/ml) (p < 0.001). Leptin increased from ages 6 to 8 in girls, but remained steady in boys. In both sexes, leptin increased significantly (p < 0.001) across weight category from normal weight to obese. Children in the highest tertile of leptin concentration showed significantly (p < 0.01) lower levels of HDL-cholesterol (HDL-C) and apolipoprotein-AI (apo-AI) and significantly higher triglyceride (TG) levels than children in lower tertiles. However, in linear regression analysis, after adjustment for body mass index (BMI), leptin only accounted for 1.5% of the variance of HDL-C in boys, and 2.6% of the variance of apo-AI in girls. Leptin was strongly and positively correlated with insulin and HOMA. Upon regression analysis, leptin contributed to over 20% of the variability in insulin and HOMA, independent of BMI.

CONCLUSION

Leptin levels show sex differences in pre-pubertal children. In this age group, leptin levels are strongly related to insulin, and affect lipid profile -namely HDL-C, apo-AI and TG- particularly when leptin levels are high.

The influence of puberty on vitamin D status in obese children and the possible relation between vitamin D deficiency and insulin resistance

BACKGROUND

Puberty can affect vitamin D levels.

OBJECTIVES

The goal of this study was to analyze the relation between vitamin D deficiency and puberty in obese Spanish children, along with the possible interrelation between vitamin D status and degree of insulin resistance.

METHODS

A cross-sectional study was carried out, in which clinical and biochemical data were gathered from 120 obese and 50 normal weight children between January 2011 and January 2013.

RESULTS

Mean vitamin D levels were 19.5 and 31.6 ng/mL in obese pubertal and obese prepubertal children, respectively. About 75% of the obese pubertal subjects and 46% of the obese prepubertal subjects had vitamin D deficiency. Vitamin D levels were significantly lower in pubescent subjects compared with pre-pubescent subjects in summer, fall, and winter. There was no apparent relation between vitamin D levels and homeostasis model assessment index for insulin resistence (expressed in standard deviation score for sex and Tanner stage) in either puberty or pre-puberty.

CONCLUSION

Puberty may be a risk factor for the vitamin D deficiency commonly found in the obese child population. This deficiency is not associated with higher insulin resistance in obese pubertal children compared with obese prepubertal children.

Plasma non-esterified fatty acid levels in children and their relationship with sex steroids

OBJECTIVE

Puberty is associated with decreased insulin sensitivity. Sexual hormones have been related with the onset of insulin resistance, but their relationship with non-esterified fatty acids (NEFA) remains unexplored. The aim of this study was to evaluate circulating NEFA levels in population-based samples of prepubertal children and adolescents and to analyze the association of NEFA with obesity, insulin resistance, and sexual hormones in adolescents.

EXPERIMENTAL

The studied population included 854 randomly selected 6-8-year-old children and 822 children aged 12-16years. NEFA levels were determined using a commercial kit. Testosterone and estradiol levels were determined by RIA, and insulin and sex hormone binding protein by IRMA. HOMA was calculated as an indicator of insulin resistance.

RESULTS

NEFA levels were lower in adolescents than in 6-8-year-old children, and decreased progressively with age between 12-year-olds and 16-year-olds. No significant differences in NEFA levels were observed between obese and non-obese adolescents. NEFA were not correlated with insulin or HOMA in 12-16-year-old girls, and appear negatively correlated with these variables in boys. Insulin and HOMA were negatively correlated with SHBG levels in both sexes adjusting by age but NEFA levels were not.

CONCLUSIONS

NEFA levels decrease with age in adolescents and are not significantly increased in obese children, supporting the fact that the decreased insulin sensitivity at this age is not affecting NEFA metabolism. Although SHBG is related to insulin and HOMA independently of age in both sexes, SHBG levels are not associated with NEFA.

Association of resistin polymorphisms with resistin levels and lipid profile in children

Previous research has found a correlation between resistin and lipid level variations. Polymorphisms in the resistin gene (RETN) could be involved in this relationship, but the results of the different studies are contradictory. The aim of this study was to examine the association between resistin and lipid levels, and to determine whether resistin polymorphisms are associated with resistin levels and lipid profile in prepubertal children and adolescents. The single nucleotide polymorphisms (SNPs) rs1862513 and rs10401670 were analyzed in 442 randomly selected 6- to 8-year-old children and 827 children aged 12-16 years. Anthropometric data were recorded. Lipid profile was determined using standard methods. Serum resistin levels were measured using a multiplexed bead immunoassay. Resistin polymorphisms were determined by TaqMan(®) allelic discrimination assays. A relationship was found between serum levels of resistin and the SNP rs10401670 in 6- to 8-year-old boys. SNP rs10401670 was also related to TC and LDL-cholesterol in 12- to 16-year-old boys and to HDL-C in 12- to 16-year-old girls. SNP rs1862513 was not related to any of the studied variables. Serum resistin levels were significantly and negatively associated with ApoAI levels in 12- to 16-year-old girls. A SNP in the 3'UTR region of RETN (rs10401670) is associated with resistin levels and lipid profile in children, showing different associations depending on age and gender.

Resistin levels are related to fat mass, but not to body mass index in children

The relationship of resistin levels with obesity remains unclear. The aim of this study was to determine resistin levels in prepubertal children and adolescents and evaluate their association with anthropometric parameters and body composition. The study population included 420 randomly selected 6-8-year-old children and 712 children aged 12-16 years. Anthropometric data were measured and body mass index (BMI) and waist-to-hip and waist-to-height ratios were calculated. Body composition was assessed using an impedance body composition analyzer. Serum resistin levels were determined using a multiplexed bead immunoassay. Resistin levels were not significantly different between sexes. No significant differences in serum resistin concentrations were found between obese, overweight, and normal weight children at any age, and no significant correlations were observed between resistin concentrations and weight or BMI. However, resistin levels showed a significant positive correlation with fat mass in 12-16-year-old children, particularly in girls. In addition to describing serum resistin levels in prepubertal children and adolescents, our study suggests that resistin is related to body fat rather than to BMI in adolescents.

[High prevalence of vitamin D deficiency among spanish obese children and adolescents]

INTRODUCTION

Vitamin D deficiency has been associated with extra-skeletal outcomes such as, insulin resistance, type 2 diabetes, and cardiovascular disease. The aim of this study is to determine the prevalence of vitamin D deficiency among obese children and adolescents in Spain and to analyze the relationship between 25-OH-vitamin D (25-OH-D) levels and markers of abnormal glucose metabolism.

PATIENTS AND METHODS

A cross-sectional study was conducted in which the clinical and biochemical data were recorded for 120 obese and 50 non-overweight children in Pediatric Clinics from January 2011 to January 2013.

RESULTS

The mean 25-OH-D levels among obese children was 19.5 ng/ml and among non-overweight children was 31.6 ng/ml. 58,3% of obese subjects, and 10% of non-overweight subjects had vitamin D deficiency. Serum 25-OH-D levels were lower in winter. Higher HOMA-SDS (3.8 versus 2.4), and triglycerides (97 versus 81 mg/dl) were found in vitamin D deficient obese children compared to obese children without vitamin D deficiency. A negative correlation was found between 25-OH-D levels and HOMA in absolute values (r=-0.2; P=.04) that was not maintained when HOMA-SDS was analyzed.

CONCLUSIONS

There is a high prevalence of vitamin D deficiency among obese children with a multifactorial etiology. A lower 25-OH-D level could be a risk factor for developing insulin resistance and type 2 diabetes in obese population.

Relationship of adiponectin with sex hormone levels in adolescents

BACKGROUND/AIMS

Adiponectin is an adipose tissue-derived adipocytokine which, starting at puberty, is present in lower levels in males than in females. In adults, a relationship between adiponectin levels and sexual hormones has been suggested, but this association remains unclear in children. Our study aimed to analyze the relationship of adiponectin with dehydroepiandrosterone sulfate, testosterone, estradiol, and sex hormone-binding globulin (SHBG) in adolescents.

METHODS

The population-based sample included 785 healthy 12- to 16-year-old children. Testosterone, estradiol, and dehydroepiandrosterone sulfate levels were assessed by radioimmunoassay. SHBG was measured by immunoradiometric assay. Adiponectin concentrations were measured by ELISA.

RESULTS

Adiponectin levels were positively correlated with SHBG and negatively correlated with the free androgen index independently of body mass index (BMI) and fat mass. No significant correlations were observed between adiponectin and total testosterone or estradiol. Multiple linear regression analysis showed that, after adjustment for BMI, SHBG appears as the primary predictor of adiponectin levels in both sexes, accounting for 5.7% of the variation in adiponectin levels in boys and 7.5% in girls.

CONCLUSION

Adiponectin is related to free androgen index and SHBG levels in adolescents after adjusting for BMI and fat mass, thus suggesting an association between adiponectin levels and androgen bioavailability that would explain the sex-based differences in adiponectin levels through life.

High tracking of apolipoprotein B levels from the prepubertal age to adolescence in Spanish children

AIM

To assess tracking of lipid and apolipoproteins from the prepubertal age (baseline, 6-8 years old) to adolescence (follow-up, 13-16 years old) in Spanish children.

METHODS

The sample population included 385 healthy children (179 boys and 206 girls). Tracking was estimated by correlations between baseline and follow-up levels, multiple regression models in which the follow-up lipid was the dependent variable and analysing the percentage of individuals who remained in the same lipid levels status from prepubertal age to adolescence.

RESULTS

Correlations between baseline and follow-up levels for low density lipoprotein (LDL)-cholesterol and apolipoprotein B (apo B) were stronger in boys and for high density lipoprotein-cholesterol and apo A-I stronger in girls. Regression analyses showed that, after adjusting by body mass index (BMI), baseline LDL-cholesterol and apo B levels explain 23% and 39% of the variation of follow-up LDL-cholesterol and apo B levels, respectively, in boys and 13% and 22%, respectively, in girls. The strength of tracking for LDL-cholesterol and apo B was 79% and 89%, respectively, in boys and 72% and 82%, respectively, in girls.

CONCLUSION

Apolipoprotein B showed the strongest tracking in both sexes, stronger than for LDL-cholesterol, which supports the importance of determining apo B levels as a marker of dyslipidaemia in children.

Relationship of dehydroepiandrosterone sulfate with overweight and insulin sensitivity in 12-16-year-old Spanish children

DHEA-S is the most abundant steroid hormone in human circulation. Although a relationship of DHEA-S with obesity-related diseases has been reported, the metabolic role of this hormone remains unclear, particularly in children. In our study, we have investigated the relationship of DHEA-S levels with anthropometric variables, insulin, HOMA, and free fatty acids in adolescents. The study sample included 812 healthy 12-16-year-old children (383 boys and 429 girls). Plasma DHEA-S was determined by RIA, insulin concentrations by IRMA, and free fatty acids by using a commercial kit. Insulin resistance was estimated using the HOMA index. No significant differences in plasma DHEA-S levels were found between sexes. DHEA-S levels in overweight children were significantly higher than in normal-weight children. DHEA-S levels were significantly correlated with weight and BMI after adjusting for age. Significant positive correlations between DHEA-S and free fatty acids levels were found after adjusting for age and BMI, particularly in boys, but not between DHEA-S levels and insulin or HOMA in either gender. DHEA-S levels in 12-16-year-old children are correlated with weight and BMI independently of age. We failed to find any association between DHEA-S and insulin levels, but we did find a -significant correlation between DHEA-S and free fatty acids levels, suggesting that its association with free fatty acids may be related to the onset of the association of DHEA-S with insulin resi-stance.

Relationship between polymorphisms in the sulfotransferase SULT2A1 gene and dehydroepiandrosterone sulfate concentration in children

Dehydroepiandrosterone sulfate (DHEA-S) is the most abundant circulating steroid hormone in humans, and has important physiological effects. A relationship has been suggested between variations of DHEA-S concentration and polymorphisms in the gene encoding sulfotransferase (SULT2A1), an enzyme that catalyzes the formation of DHEA-S from DHEA. We have investigated the relationship between the single nucleotide polymorphisms (SNPs) rs2637125 and rs182420 in the SULT2A1 gene and plasma DHEA-S concentration in children at two different ages. The sample population comprised 981 healthy 6-8-year-olds and 792 12-16-year-old children. In total, 12-16-year-old boys homozygous for the rare allele of rs182420 (CC) showed significantly lower DHEA-S concentration than TC boys, and both (TC and CC) had lower levels than TT boys. In all, 12-16 -year-old boy carriers of the rare allele for the rs2637125 polymorphism also showed lower levels of DHEA-S than GG carriers. No differences were observed in DHEA-S concentrations across genotypes in 6-8-year-old children. Our data show an age-related association of polymorphisms in the SULT2A1 gene with lower DHEA-S, suggesting that these polymorphisms may affect DHEA-S concentration in adults.

Obesity in Spanish Schoolchildren: Relationship with Lipid Profile and Insulin Resistance

This article reports cross-sectional data from a total of 1048 children, 6 to 8 years of age, categorized by presence or absence of obesity, who participated in a voluntary survey of cardiovascular risk factors in Spain over the period of 1998 to 2000, to establish the relationship between obesity and its metabolic consequences at this age. The prevalence of obesity and overweight were 9.4% and 15.7%, respectively, in boys and 10.5% and 18.0%, respectively, in girls. We observed that, in both sexes, obese children had higher triglycerides and lower high-density lipoprotein-cholesterol levels than non-obese children. No differences were found in plasma glucose or low-density lipoprotein-cholesterol levels between normal and obese children. However, we observed that insulin levels and the homeostasis model assessment for insulin resistance were significantly (p<0.001) higher in obese children of both sexes but that free fatty acid levels were lower in obese children than in nonobese children, with a statistical significance in girls (0.72+/-0.30 vs. 0.61+/-0.16 mEq/liter). In summary, our survey found some metabolic consequences of obesity similar to those found in adults (elevated triglycerides, insulin, and the homeostasis model assessment for insulin resistance, and lower high-density lipoprotein-cholesterol). However, other features (glucose, total cholesterol, low-density lipoprotein-cholesterol, and free fatty acid levels) were found to behave differently, indicating that the association of obesity with risk factors seems to change as the children age and may depend on the chronology of sexual maturation.

Influence of the interaction between the adiponectin G276T polymorphism and body mass index on lipid levels in healthy children

Adiponectin is an adipose tissue-specific hormone which is inversely associated with metabolic alterations related to atherosclerosis. Polymorphisms in the adiponectin gene (AdipoQ) have been related to low adiponectin levels as well as several cardiovascular risk factors, but this association remains controversial. In our study we investigated the relationship between the AdipoQ T45G (rs: 2241766) and G276T (rs: 1501299) polymorphisms and adiponectin concentrations, blood pressure, and lipid and insulin levels, in a population-based sample of 12- to 16-year-old children. The study included 815 healthy Spanish children (388 boys and 427 girls). Plasma glucose and lipid levels were determined by standard methods. Insulin concentrations were measured by RIA, and serum adiponectin levels were determined by ELISA. The AdipoQ T45G and AdipoQ G276T polymorphisms were determined by TaqMan(®) allelic discrimination assays. ANOVA or t test allowed for comparison of the studied parameters across genotypes or genotype groups, respectively. A linear regression analysis was performed to examine the independent relationships of the lipid variables with BMI (body mass index), AdipoQ G276T polymorphism and the interaction between the two. When independently comparing the effect of these polymorphisms in normal-weight and overweight children, we observed that overweight boys carriers of the minor allele T had significantly lower TC, LDL-C and apo A-I levels than non-carriers, but these differences were not apparent in normal-weight boys. Furthermore, linear regression analysis demonstrated that interaction between the BMI and the AdipoQ G276T polymorphism is a significant factor explaining the variations of TC and LDL-C levels. To our knowledge, this is the first study to report an association between the AdipoQ G276T polymorphism and lipid levels in overweight boys alone, thereby suggesting that the influence of the AdipoQ polymorphisms on cardiovascular risk factors may be dependent on BMI.