Diversity of metabolic syndrome risk factors in obese children and adolescents

The aim of this study was to investigate the frequency of metabolic syndrome (MS) variables in a group of spanish obese children and adolescents, to asses MS prevalence in this population and to describe it's relationship with other metabolic risk factors. 103 children were studied : 54 male and 49 female, mean age 10.08+/-2.3 with exogenous obesity. Obesity was defined when BMI was higher than the age and sex specific equivalent to 30 kg/m(2) in adults. MS variables considered were waist circumference, blood pressure, fasting blood triglycerides, fasting glucose/insulin and HDL-cholesterol. The children were considered as having the MS when three or more characteristics showed abnormal values according to Cook and De Ferranti definitions. HOMA index, ApoB and ApoA1 were studied too. The most frequent features of the metabolic syndrome were excess waist circumference and hypertension. The MS markers with the lowest frequency were dyslipidemia and fasting hyperglicemia. MS prevalence was 29,9% (Cook et al. criteria) and 50% (De Ferranti et al. criteria). Fasting insulin and HOMA index values increased significantly (p < 0.05) when three or more abnormalities of the MS variables were present. Apo B increased significantly only in females (p < 0.05) and Apo Al decreased significantly (p < 0.05) in both sexes when MS was present. Adequate metabolic syndrome risk factors criteria, mainly cut-off values, need to be defined in the European paediatric population.     

Nematode infections are risk factors for staphylococcal infection in children

Nematode infection may be a risk factor for pyogenic liver abscess in children and we hypothesized that the immunomodulation induced by those parasites would be a risk factor for any staphylococcal infection in children. The present study was designed to compare, within the same hospital, the frequency of intestinal nematodes and Toxocara infection in children with and without staphylococcal infections. From October 1997 to February 1998, 80 children with staphylococcal infection and 110 children with other diseases were submitted to fecal examination, serology for Toxocara sp., evaluation of plasma immunoglobulin levels, and eosinophil counts. Mean age, gender distribution, birthplace, and socioeconomic conditions did not differ significantly between the two groups. Frequency of intestinal nematodes and positive serology for Toxocara, were remarkably higher in children with staphylococcal infections than in the non-staphylococcal group. There was a significant correlation between intestinal nematodes or Toxocara infection and staphylococcal infection in children, reinforced by higher eosinophil counts and higher IgE levels in these children than in the control group. One possible explanation for this association would be the enhancement of bacterial infection by the immunomodulation induced by helminth infections, due to strong activation of the Th2 subset of lymphocytes by antigens from larvae and adult worms.     

Visceral fat and liver fat are independent predictors of metabolic risk factors in men

We examined the independent associations among abdominal adipose tissue (AT), liver fat, cardiorespiratory fitness (CRF), and lipid variables in 161 Caucasian men who had a wide variation in adiposity. We measured AT and liver fat by computed tomography and CRF by a maximal exercise test on a treadmill. Visceral AT remained a significant (P or= 0.05) correlate of any lipid variable after control for visceral AT and CRF. Furthermore, subdivision of subcutaneous AT into deep and superficial depots did not alter these observations. Visceral AT was the strongest correlate of liver fat and remained so after control for abdominal subcutaneous AT, CRF, and alcohol consumption (r = -0.34, P < 0.01). In contrast, abdominal subcutaneous AT and CRF were not significant (P > 0.10) correlates of liver fat after control for visceral AT. Visceral AT remained a significant (P < 0.01) correlate of TG, HDL-C, and TC/HDL-C independent of liver fat. However, liver fat was also a significant correlate (P 相似文献   

From metabolic normality to cardiometabolic risk factors in subjects with obesity

The aim of the study was to evaluate the 3 years incidence of cardiometabolic risk factors, such as impaired fasting glucose, reduced high-density lipoprotein (HDL)-cholesterol, increased plasma triglycerides or blood pressure as well as impaired glucose tolerance in overweight or obese (ow/ob) and normal body weight (nbw) subjects metabolically normal at baseline. Subjects from the Relationship between Insulin Sensitivity and Cardiovascular Disease (RISC) study were analyzed. We analyzed 284 nbw and 152 ow/ob subjects who, at baseline, did not show any of the above-mentioned cardiometabolic risk factors. At 3 years, these parameters were re-evaluated. Intima-media thickness (IMT) of the common carotid artery (CCA) was echographically measured. At follow-up, the incidence of one or more cardiometabolic risk factors was 57.2% in ow/ob vs. 31.7% in nbw (P < 0.0001). After adjustment for age, sex, menopause status, lifestyle parameters, insulin sensitivity, and fasting insulinemia, BMI remained significantly linked to the development of one or more cardiometabolic risk factors (P = 0.02). An increased BMI at follow-up was significantly associated with the development of cardiometabolic alterations, in both nbw and ow/ob groups (P = 0.04). Ow/ob subjects who, at 3 years follow-up, remained metabolically normal, showed a less favourable cardiometabolic profile, when compared to nbw counterparts. In ow/ob metabolically normal males and females, intima-media of the common carotid at follow-up was thicker than in nbw (P = 0.03 for males, P = 0.04 for females). In conclusion, metabolically normal obese subjects show a higher incidence of cardiometabolic risk factors, in a short follow-up period. Weight gain is significantly associated with the development of these factors, in both nbw and ow/ob subjects.     

Abdominal fat and metabolic risk in obese children and adolescents

The aim of this study was to investigate fat distribution, mainly abdominal fat, and its relationship with metabolic risk variables in a group of 126 children and adolescents (60 males and 66 females) aged 5.0 to 14.9. According to IOTF criteria, 46 were classified as normal weight, 28 overweight and 52 obese. Weight, height, waist (WC) and hip circumferences were measured. The body mass index (BMI) was calculated. Total body fat, trunkal and abdominal fat were also assessed by dual energy x-ray absorptiometry (DXA). Glucose, insulin, HDL-Cholesterol, triglycerides (TG), ferritine, homocystein and C-reactive protein (CRP) were measured. Obesity status was related with insulin concentrations, CRP, TG and HDL. Obese patients had higher abdominal fat and higher CRP values than overweight and normal subjects. All markers of central body adiposity were related with insulin and lipid metabolism; however, they were not related with homocystein or ferritin. A simple anthropometric measurement, like waist circumference, seems to be a good predictor of the majority of the obesity related metabolic risk variables.     

Atherosclerosis risk factors in children of high risk families

The Objective of this study was to determine the frequency of care reactive atherosclerosis risk factors in children of parents with premature coronary heart disease observed before their 45 years of age for the promotion of the effectivity of the preventive work started in childhood and adolescent ages. METHODS: Height and weight was measured. Body mass index (BMI) was calculated. Fat analysis was performed in children with overweight. Blood pressure was measured and both 24 hour monitoring and fundoscopy were performed in cases with a blood pressure higher than 90 centile values. Fasting blood sugar (BS) level was measured. Oral glucose tolerance test was made in cases with a fasting BS level higher than 5 mmol/l. Serum total cholesterol (TC), HDL-cholesterol (HDLC) and total triglyceride (TT) levels were measured and LDL-cholesterol (LDLC) level was calculated. The plasma thiobarbituric acid reactive system (TBARS) was investigated. Statistical analyses were performed by chi2 and Student t-probes. Data of 1140 offsprings and 457 referents without any high atherosclerotic risk family history were analyzed. RESULTS: BMI of 87 offsprings was higher than the 90 centile value. The fat percent of the body of these children was higher than 40. The blood pressure of 311 children and adolescents was higher than the 90 centile value. Fasting BS level was higher than 5 mmol/l in 47 cases 17 of them showed a pathologic oral glucose tolerance test. High serum TC level was observed in 67 cases, high serum TT level was found in 8 cases. 245 offsprings had a low serum HDLC level. The plasma TBARS level was high in 241 cases. Data of referents differed significantly from those of offsprings. Their serum TC, LDLC levels and plasma TBARS level were lower, serum HDLC level was higher than that of children and adolescents with high risk atherosclerotic family history. CONCLUSION: Risk factors of atherosclerosis are detectable in children and adolescents of high risk families. The measurement of these factors may help the efficacy of the preventive work.     

Abdominal adipose tissue cytokine gene expression: relationship to obesity and metabolic risk factors

Adipose tissue is a major source of inflammatory and thrombotic cytokines. This study investigated the relationship of abdominal subcutaneous adipose tissue cytokine gene expression to body composition, fat distribution, and metabolic risk during obesity. We determined body composition, abdominal fat distribution, plasma lipids, and abdominal subcutaneous fat gene expression of leptin, TNF-alpha, IL-6, PAI-1, and adiponectin in 20 obese, middle-aged women (BMI, 32.7 +/- 0.8 kg/m2; age, 57 +/- 1 yr). A subset of these women without diabetes (n = 15) also underwent an OGTT. In all women, visceral fat volume was negatively related to leptin (r = -0.46, P < 0.05) and tended to be negatively related to adiponectin (r = -0.38, P = 0.09) gene expression. Among the nondiabetic women, fasting insulin (r = 0.69, P < 0.01), 2-h insulin (r = 0.56, P < 0.05), and HOMA index (r = 0.59, P < 0.05) correlated positively with TNF-alpha gene expression; fasting insulin (r = 0.54, P < 0.05) was positively related to, and 2-h insulin (r = 0.49, P = 0.06) tended to be positively related to, IL-6 gene expression; and glucose area (r = -0.56, P < 0.05) was negatively related to, and insulin area (r = -0.49, P = 0.06) tended to be negatively related to, adiponectin gene expression. Also, adiponectin gene expression was significantly lower in women with vs. without the metabolic syndrome (adiponectin-beta-actin ratio, 2.26 +/- 0.46 vs. 3.31 +/- 0.33, P < 0.05). We conclude that abdominal subcutaneous adipose tissue expression of inflammatory cytokines is a potential mechanism linking obesity with its metabolic comorbidities.     

AKT1 polymorphisms are associated with risk for metabolic syndrome

Converging lines of evidence suggest that AKT1 is a major mediator of the responses to insulin,insulin-like growth factor 1 (IGF1), and glucose. AKT1 also plays a key role in the regulation of both muscle cell hypertrophy and atrophy. We hypothesized that AKT1 variants may play a role in the endophenotypes that makeup metabolic syndrome. We studied a 12-kb region including the ?rst exon of the AKT1 gene for association with metabolic syndrome-related phenotypes in four study populations [FAMUSS cohort (n = 574; age 23.7 ± 5.7 years), Strong Heart Study (SHS) (n = 2,134; age 55.5 ± 7.9 years), Dynamics of Health, Aging and Body Composition (Health ABC) (n = 3,075; age 73.6 ± 2.9 years), and Studies of a Targeted Risk Reduction Intervention through De?ned Exercise (STRRIDE)(n = 175; age 40–65 years)]. We identi?ed a three SNP haplotype that we call H1, which represents the ancestral alleles eles at the three loci and H2, which represents the derived alleles at the three loci. In young adult European Americans (FAMUSS), H1 was associated with higher fasting glucose levels in females. In middle age Native Americans (SHS), H1 carriers showed higher fasting insulin and HOMA in males, and higher BMI in females. Inolder African-American and European American subjects(Health ABC) H1 carriers showed a higher incidence of metabolic syndrome. Homozygotes for the H1 haplotype showed about twice the risk of metabolic syndrome in both males and females (p\0.001). In middle-aged European Americans with insulin resistance (STRRIDE) studied by intravenous glucose tolerance test (IVGTT), H1 carriers showed increased insulin resistance due to the Sg component (p = 0.021). The 12-kb haplotype is a risk factor for metabolic syndrome and insulin resistance that needs to be explored in further populations.     

Diazotrophs are overlooked contributors to carbon and nitrogen export to the deep ocean

Diazotrophs are widespread microorganisms that alleviate nitrogen limitation in 60% of our oceans, thereby regulating marine productivity. Yet, the group-specific contribution of diazotrophs to organic matter export has not been quantified, which so far has impeded an accurate assessment of their impact on the biological carbon pump. Here, we examine the fate of five groups of globally-distributed diazotrophs by using an original combination of mesopelagic particle sampling devices across the subtropical South Pacific Ocean. We demonstrate that cyanobacterial and non-cyanobacterial diazotrophs are exported down to 1000 m depth. Surprisingly, group-specific export turnover rates point to a more efficient export of small unicellular cyanobacterial diazotrophs (UCYN) relative to the larger and filamentous Trichodesmium. Phycoerythrin-containing UCYN-B and UCYN-C-like cells were recurrently found embedded in large (>50 µm) organic aggregates or organized into clusters of tens to hundreds of cells linked by an extracellular matrix, presumably facilitating their export. Beyond the South Pacific, our data are supported by analysis of the Tara Oceans metagenomes collected in other ocean basins, extending the scope of our results globally. We show that, when diazotrophs are found in the euphotic zone, they are also systematically present in mesopelagic waters, suggesting their transport to the deep ocean. We thus conclude that diazotrophs are a significant part of the carbon sequestered in the deep ocean and, therefore, they need to be accounted in regional and global estimates of export.Subject terms: Biogeochemistry, Microbiology     

Relation of serum calcium concentration to metabolic risk factors for cardiovascular disease.

Data from a health screening survey with over 18,000 adult participants were used to determine the relations between serum calcium concentration and the cardiovascular risk factors hypertension, hyperglycaemia, and hyperlipidaemia. Blood pressure and serum glucose and cholesterol concentrations were all positively related to each other independent of age, sex, kidney function, and obesity. Similar relations between the risk factors were found in subjects with hypertension or hyperglycaemia independent of the degree of overweight. These results suggested that there might be a metabolic syndrome of cardiovascular risk factors. Serum calcium concentration was positively related to systolic and diastolic blood pressures and serum glucose and cholesterol concentrations. Thus a common feature in the syndrome is an increased serum calcium concentration. The relations between serum calcium concentrations and the cardiovascular risk factors were not limited to the upper parts of the distribution, being seen over a wide range. Changes in calcium metabolism seem to be related to a metabolic syndrome of hypertension, impaired glucose tolerance, and hyperlipidaemia.     

Long-term cyclosporine treatment in non-transplanted rats and metabolic risk factors of vascular diseases

Cyclosporine (CsA) is an immunosuppressive agent frequently used in the clinic for prevention of allograft rejection and for the treatment of autoimmune diseases. Despite its desired action on the immune system, CsA treatment may present serious adverse effects, which are masked by the concomitant use of other drugs. The search for effective immunosuppression protocols which does not affect the quality of life of patients is driving research to investigate the CsA involvement in vascular diseases, frequent in patients under immunosuppression. Thus, 45 non-transplanted Wistar rats were treated for 8 weeks with vehicle or 5 or 15 mg/kg CsA (n = 15/group) by gavage administration to evaluate the specific influence of cyclosporine on the levels of risk factors (metabolic and inflammatory) of vascular disease and its mechanism of action. Therefore, serum insulin levels, glucose tolerance test, serum lipids profile, total homocysteine and fibrinogen levels were assessed. The biochemical alterations reported here suggest the development of a framework straight to diabetes. Glucose homeostasis was affected as indicated by decreased insulin levels and altered glucose tolerance test in CsA 15 mg/kg group compared to other groups. Serum insulin and total homocysteine levels presented a significant negative correlation (R = ? 0.76, P < 0.0001). Fibrinogen and serum lipids profiles were significantly increased in CsA 15 mg/kg group compared to other groups and correlated positively with total homocysteine levels. Considering the well-established correlation among insulin resistance, lipid and total homocysteine levels, hypercoagulability and atherosclerosis, we can assume that this protocol of long-term CsA treatment in non-transplanted rats alter biochemical parameters related to cardiovascular and cerebrovascular risk, mainly in CsA 15 mg/kg group. Insulin and tHcy serum levels appear to be central in this process.     

Relationship of metabolic risk factors and development of cardiovascular disease and diabetes

The prevalence of obesity and diabetes has reached pandemic proportions. Obesity, particularly in association with high waist circumference and high BMI, is an independent risk factor for coronary heart disease (CHD) and diabetes. Several large studies have shown that marginal (5 lb) to moderate (11 to 22 lb) weight gain in adulthood (age 20 to 50 years) increases the risk of chronic disease and negatively affects CHD risk status. The metabolic syndrome, a clustering of cardiovascular and metabolic risk factors that includes abdominal obesity, is increasing among adults and children and is strongly associated with the development of diabetes and CHD. Recent evidence suggests that elevated liver enzymes, an indicator of non-alcoholic fatty liver disease, may comprise an additional component of the metabolic syndrome and may serve as a surrogate marker for type 2 diabetes, particularly if used in conjunction with C-reactive protein.     

Substrate-energy metabolism and metabolic risk factors for cardiovascular disease in relation to fetal growth and adult body composition

The effect of fetal programming on intermediary metabolism is uncertain. Therefore, we examined whether fetal programming affects oxidative and nonoxidative macronutrient metabolism and the prevalence of the metabolic syndrome in adult life. Healthy older men, aged 64-72 years, with either a lower birth weight (LBW, or=75th %ile; n = 13) had measurements of 1) net oxidative metabolism using indirect calorimetry before and for 6 h after a mixed meal (3,720 kJ) and 2) postprandial oxidation of exogenous [13C]palmitic acid. Body composition was measured using dual-energy X-ray absorptiometry. After adjustment for current weight and height, the LBW group had a lower resting energy expenditure (REE) in the preprandial (4.01 vs. 4.54 kJ/min, P = 0.015) and postprandial state (4.60 vs. 5.20 kJ/min, P = 0.004), and less fat-free mass than the HBW group. The BW category was a significant, independent, and better predictor of REE than weight plus height. There were no significant differences between groups in net oxidative and nonoxidative macronutrient (protein, fat, carbohydrate) metabolism (or of exogenous [13C]palmitate) or in the prevalence of the metabolic syndrome, which was present almost twice as commonly in the LBW than in the HBW group. The study suggests that fetal programming affects both pre- and postprandial EE in older life by mechanisms that are at least partly related to the mass of the fat-free body. BW was found to be a significant predictor of REE that was independent of adult weight plus height.