Insulin resistance and the metabolic syndrome--or the pitfalls of epidemiology

Persistent sleep-disordered breathing independently contributes to metabolic syndrome in prepubertal children

BACKGROUND

Obstructive sleep apnea (OSA) is a risk factor for metabolic syndrome (MetS) in adults, but its association in prepubertal children is still questionable due to the relatively limited cardiometabolic data available and the phenotypic heterogeneity.

OBJECTIVE

To identify the role of OSA as a potential mediator of MetS in prepubertal children.

METHODS

A total of 255 prepubertal children from the Childhood Adenotonsillectomy Trial were included, with standardized measurements taken before OSA treatment and 7 months later. MetS was defined if three or more of the following criteria were present: adiposity, high blood pressure, elevated glycemia, and dyslipidemia. A causal mediation analysis was conducted to assess the effect of OSA treatment on MetS.

RESULTS

OSA treatment significantly impacted MetS, with the apnea-hypopnea index emerging as mediator (p = .02). This mediation role was not detected for any of the individual risk factors that define MetS. We further found that the relationship between MetS and OSA is ascribable to respiratory disturbance caused by the apnea episodes, while systemic inflammation as measured by C-reactive protein, is mediated by desaturation events and fragmented sleep. In terms of evolution, patients with MetS were significantly more likely to recover after OSA treatment (odds ratio = 2.56, 95% confidence interval [CI] 1.20-5.46; risk ratio = 2.06, 95% CI 1.19-3.54) than the opposite, patients without MetS to develop it.

CONCLUSION

The findings point to a causal role of OSA in the development of metabolic dysfunction, suggesting that persistent OSA may increase the risk of MetS in prepubertal children. This mediation role implies a need for developing screening for MetS in children presenting OSA symptoms.

Risk of incident type 2 diabetes in patients with psoriatic arthritis: A systematic review and meta-analysis of cohort studies

OBJECTIVES

To determine the risk of type 2 diabetes among patients with psoriatic arthritis (PsA).

METHODS

Electronic database searches of PubMed, EMBASE and Cochrane Library were performed from inception to June 2020 and updated in May 2022. Cohort studies were included if they reported hazard ratios (HR) or relative risks with 95% confidence interval (CI) of incident diabetes in patients with PsA compared with non-rheumatic populations. Pooled HR and 95% CI were calculated using a DerSimonian and Laird method random-effects model.

RESULTS

A total of 5 studies comprising 37 811 PsA patients with 174 825 patient-years and 476 838 non-rheumatic controls with 2 945 358 patient-years were identified and included in our data analysis. During the follow-up, 2335 and 23 035 incident diabetes were observed in PsA and non-rheumatic control groups, corresponding to a crude incidence rate of 13.4 and 7.8 per 1000 patient-years, respectively. The pooled age- and gender-adjusted, and fully adjusted HR of incident diabetes in patients with PsA compared with non-rheumatic populations were 1.54 (95% CI: 1.43-1.67, I²  = 50.8%) and 1.38 (95% CI: 1.31-1.47, I²  = 0.0%), respectively.

CONCLUSIONS

Our study indicates a 38% increase in the risk of type 2 diabetes among patients with PsA, with an incidence rate of 13.4 per 1000 patients-years. These findings suggest the awareness of managing diabetes with careful screening of PsA patients in daily practice.

Changes of Serum Adiponectin and Glycated Albumin Levels in Gestational Diabetes Mellitus Patients and Their Relationship with Insulin Resistance

Background:

We aimed to investigate the changes of serum adiponectin and glycated albumin (GA) levels in gestational diabetes mellitus patients and their relationship with insulin resistance.

Methods:

Overall, 137 pregnant women were enrolled from Jinan City People's Hospital, Laiwu District, China from Jan 2015 to Jun 2018. Among them, 71 pregnant women with gestational diabetes mellitus were examined as diabetes group, and 66 normal pregnant women as normal pregnant women group. In addition, 58 normal non-pregnant women of childbearing age who were examined in our hospital during the same period were selected as a control group. The serum adiponectin and GA levels of the three groups were compared, and the relationship between serum adiponectin, GA levels and insulin resistance was analyzed.

Results:

The serum adiponectin level of pregnant women in gestational diabetes mellitus (GDM) group was significantly lower than that of normal pregnant women and control group (P=0.031, P=0.027). The serum GA level of pregnant women in GDM group was significantly higher than that of normal pregnant women and control group (P<0.001). Pearson correlation analysis showed that GA was positively correlated with Fasting plasma glucose (FPG), Fasting insulin (FINS) and Insulin resistance index(HOMA-IR) levels (P<0.001), while adiponectin was negatively correlated with FPG FINS and HOMA-IR levels (P<0.001).

Conclusion:

Abnormal levels of serum GA and adiponectin are closely related to insulin resistance in patients with gestational diabetes mellitus. Detection of serum GA and adiponectin levels can diagnose gestational diabetes mellitus quickly and effectively.

Anti-Metabolic Syndrome Effects of Fucoidan from Fucus vesiculosus via Reactive Oxygen Species-Mediated Regulation of JNK, Akt, and AMPK Signaling

Recent studies have reported that dietary fiber improved metabolic syndrome (MetS). However, the effects of fucoidans on MetS were still not clear. In this study, we evaluated the activity of fucoidan from Fucus vesiculosus (FvF) on attenuating MetS and first elucidated the underlying mechanism. In vitro, FvF treatment remarkably lowered the level of reactive oxygen species (ROS) compared with the sodium palmitate (PA)-induced insulin resistance (IR) group. The phosphorylation level of c-Jun N-terminal kinase (JNK) was significantly decreased, while phosphorylation of protein kinase B (pAkt) level increased, compared with that of the HepG2 cells treated with PA. Thus, FvF increased glucose consumption and relieved IR via ROS-mediated JNK and Akt signaling pathways. In addition, these changes were accompanied by the activation of adenosine 5'-monophosphate-ativated protein kinase (AMPK) and its downstream targets (e.g., HMG-CoA reductase (HMGCR), acetyl-CoA carboxylase (ACC), and sterol-regulatory element-binding protein-1c (SREBP-1C)), which improved lipid metabolism in IR HepG2 cells. In vivo, FvF improved hyperglycemia and decreased serum insulin level in mice with MetS. Furthermore, we evaluated the inhibition of glucose transport by in vitro (Caco-2 monolayer model), semi-in vivo (everted gut sac model) and oral glucose tolerance test (OGTT), which indicated that FvF could significantly reduce the absorption of glucose into the blood stream, thus it could improve blood-glucose levels and IR in mice with MetS. Moreover, FvF decreased serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) levels and liver lipid accumulation, while increased the serum high density lipoprotein cholesterol (HDL-C) level in mice with MetS. Therefore, FvF could be considered as a potential candidate for the treatment of MetS by alleviating IR, inhibiting glucose transportation, and regulating lipid metabolism.

Impaired peripheral insulin sensitivity in non-obese Japanese patients with type 2 diabetes mellitus and fatty liver

AIMS/INTRODUCTION

Type two diabetes mellitus and fatty liver (FL) are not uncommon in Asians with normal body mass index. Previous studies reported a link between FL and insulin resistance. Thus, FL could coexist with insulin resistance in Asian type two diabetes mellitus patients with a normal body mass index. However, the clinical and metabolic features of such patients have not been characterized yet.

MATERIALS AND METHODS

We recruited 29 non-obese (body mass index <25 kg/m2 ) Japanese patients with early type two diabetes mellitus. Based on intrahepatic lipid level measured by H-magnetic resonance spectroscopy, the participants were divided into the FL (intrahepatic lipid ≥5%, n = 7) and non-FL groups (intrahepatic lipid <5%, n = 22).

RESULTS

Peripheral insulin sensitivity measured by hyperinsulinemic euglycemic clamp was ~25% lower in the FL group than in the non-FL group, whereas hepatic insulin sensitivity was comparable between the two groups. The subcutaneous fat area was larger, free fatty acid level was higher, C-reactive protein was higher and high molecular weight adiponectin was lower in the FL group than the non-FL group.

CONCLUSIONS

The present study showed that the metabolic features of non-obese Japanese type two diabetes patients with FL include impaired peripheral (mainly muscle) insulin sensitivity, fat accumulation and related metabolic disorders, such as elevated free fatty acid, low high molecular weight adiponectin and low-grade inflammation.

The Metabolic Syndrome in Children and Adolescents: Shifting the Focus to Cardiometabolic Risk Factor Clustering

Metabolic syndrome (MetS) was developed by the National Cholesterol Education Program Adult Treatment Panel III, identifying adults with at least 3 of 5 cardiometabolic risk factors (hyperglycemia, increased central adiposity, elevated triglycerides, decreased high-density lipoprotein cholesterol, and elevated blood pressure) who are at increased risk of diabetes and cardiovascular disease. The constellation of MetS component risk factors has a shared pathophysiology and many common treatment approaches grounded in lifestyle modification. Several attempts have been made to define MetS in the pediatric population. However, in children, the construct is difficult to define and has unclear implications for clinical care. In this Clinical Report, we focus on the importance of screening for and treating the individual risk factor components of MetS. Focusing attention on children with cardiometabolic risk factor clustering is emphasized over the need to define a pediatric MetS.

Role of sleep quality in the metabolic syndrome

Emerging evidence has assigned an important role to sleep as a modulator of metabolic homeostasis. The impact of variations in sleep duration, sleep-disordered breathing, and chronotype to cardiometabolic function encompasses a wide array of perturbations spanning from obesity, insulin resistance, type 2 diabetes, the metabolic syndrome, and cardiovascular disease risk and mortality in both adults and children. Here, we critically and extensively review the published literature on such important issues and provide a comprehensive overview of the most salient pathophysiologic pathways underlying the links between sleep, sleep disorders, and cardiometabolic functioning.

Correlation between advanced glycation end-products and the expression of fatty inflammatory factors in type II diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) is one of the most severe complications of diabetes without a clear pathogenesis. Th is study investigated the adiponectin (APN) and leptin levels in type II DCM, as well as their correlation with advanced glycation end-products (AGEs). From 2011-2013, 78 type II diabetes mellitus (T2DM) cases (40-65 years old) in the Taian region were randomly selected. Based on the results of colour Doppler ultrasonography and coronary angiography, the cases were divided into a simple T2DM group (40 cases) and a DCM group (38 cases). Forty healthy subjects were used as normal control (NC). An enzyme-linked immunosorbent assay was performed to determine the levels of fa tty inflammatory factors such as APN, leptin and AGEs, and a correlation analysis was conducted. In the T2DM group, the APN levels were decreased but the leptin and AGE levels were significantly increased compared to the NC group. In the DCM group, the APN levels were decreased but the leptin and AGE levels were significantly increased (P<0.01) compared to the T2DM group. Th e AGE levels were positively correlated with disease progression and with fasting plasma glucose levels, glycated haemoglobin, insulin resistance and leptin, but were negatively correlated with APN levels. Additionally, the APN and leptin levels were independently related to the AGE levels. Fatty inflammatory factors play a significant role in the progression of both simple T2DM and DCM. Th e results of this study revealed the pathogenesis of DCM and indicated the potential significance of AGEs in DCM prevention and treatment.

Consumption of sugar sweetened beverage is associated with incidence of metabolic syndrome in Tehranian children and adolescents

Background

Intakes of high sugar-sweetened beverages (SSBs) in adults can escalate risk of metabolic syndrome (MetS); however, data of longitudinal studies in children and adolescents are lacking. In this study we assessed consumption of SSBs in relation to incidence of MetS among children and adolescents during a 3.6 year follow-up.

Methods

This study was a population-based longitudinal study, in which 424 subjects, aged 6–18 years, from the Tehran Lipid and Glucose Study with complete data on dietary intake, blood pressure, anthropometry, and biochemical indices were followed for 3.6 years. Dietary intake was collected using a valid and reliable food frequency questionnaire. MetS was defined according to the Cook criteria. Sugar sweetened beverages included all kinds of sugar sweetened carbonated soft drinks (SSSDs) and fruit juice drinks.

Results

Average daily intakes of SSSD and fruit juice drinks were 38.5 ± 75.0 and 32.3 ± 60.1 g, respectively. After adjustment for confounders, compared to the first quartile, the odds ratio of incident MetS in the highest quartile of SSB and SSSD was 3.20 (95 % CI: 1.06–9.90) and 3.01 (95 % CI: 1.17–7.74), respectively. Regarding incidence of MetS components, compared with the lowest quartile, the highest quartile of SSSDs showed odds ratios of 2.49 (95 % CI: 1.00–6.53) for abdominal obesity and 2.79 (95 % CI: 1.02–7.64) for hypertension. No significant association was found between consumption of fruit juice drink and SSSD with other components of MetS.

Conclusions

Children and adolescents with high intakes of carbonated beverages could be at increased risk of MetS, abdominal obesity, and hypertension.

Insulin Resistance and High Sensitivity C-Reactive Protein in Migraine

Background:

A relationship between migraine and vascular disorders such as hypertension, stroke, and coronary ischemia has been recently reported. Insulin resistance and endothelial dysfunction, which commonly underlies these disorders, have not been widely investigated in migraine patients. In this study, we aimed to investigate the existence of insulin resistance and endothelial dysfunction, and their relationship to vascular risk factors in patients with migraine.

Methods:

We evaluated insulin resistance and high-sensitivity C-reactive protein (hs-CRP), a marker of endothelial dysfunction, in 60 migraine patients and 25 healthy control subjects. Multiple analysis of covariance test was used to adjust for known confounding factors that can influence insulin metabolism and endothelial function, such as obesity, blood pressure, and lipid parameters.

Results:

Insulin resistance, as measured homeostasis model assessment (HOMA)-R levels, was significantly higher in the migraine group (p<0.001). After adjustment for confounding variables, the relationship between migraine and the HOMA-R levels remained significant (p<0.001). The hs-CRP levels did not differ between the migraine and control groups.

Conclusions:

Our data show that insulin resistance is present in migraine patients. Endothelial dysfunction is not found during the headache-free period. Further studies are needed to explain the role of insulin resistance in migraine pathogenesis.

HDL2-cholesterol/HDL3-cholesterol ratio was associated with insulin resistance, high-molecular-weight adiponectin, and components for metabolic syndrome in Japanese

AIMS

Recent data have suggested a relationship between the high-density lipoprotein (HDL) subclass ratio and metabolic syndrome (MetS). However, limited information is available regarding the relationships between the HDL subclass ratio and insulin resistance, associated adipocytokine levels, and MetS components. The associations of the high-density lipoprotein 2 cholesterol (HDL2-C) to high-density lipoprotein 3 cholesterol (HDL3-C) ratio with the homeostasis model assessment of insulin resistance (HOMA-IR) index, high-molecular-weight adiponectin (HMW-Ad) levels, and MetS components were examined.

METHODS

The study included 1155 Japanese subjects who met our inclusion criteria and underwent an annual health examination that included an HDL subclass analysis.

RESULTS

The HDL2-C/HDL3-C ratio and the HMW-Ad level gradually decreased as the number of MetS components increased. In contrast, HOMA-IR gradually increased as the number of MetS components increased. The HDL2-C/HDL3-C ratio correlated inversely with HOMA-IR and positively with the HMW-Ad level. A strong positive correlation was observed between the HDL2-C/HDL3-C ratio and the HDL-C level. The HDL2-C/HDL3-C ratio exhibited moderate negative correlations with the body mass index, waist circumference, and triglyceride level. Weak negative correlations were observed for the HDL2-C/HDL3-C ratio with the systolic and diastolic blood pressure and fasting plasma glucose levels.

CONCLUSIONS

Our data indicated that the HDL2-C/HDL3-C ratio was associated with insulin resistance, the HMW-Ad level, and MetS components, and it was useful for evaluating MetS in Japanese individuals.

Baseline levels, and changes over time in body mass index and fasting insulin, and their relationship to change in metabolic trait clustering

BACKGROUND

Multiple abnormal metabolic traits are found together or "cluster" within individuals more often than is predicted by chance. The individual and combined role of adiposity and insulin resistance (IR) on metabolic trait clustering is uncertain. We tested the hypothesis that change in trait clustering is a function of both baseline level and change in these measures.

METHODS

In 2616 nondiabetic Framingham Offspring Study participants, body mass index (BMI) and fasting insulin were related to a within-person 7-year change in a trait score of 0-4 Adult Treatment Panel III metabolic syndrome traits (hypertension, high triglycerides, low high-density lipoprotein cholesterol, hyperglycemia).

RESULTS

At baseline assessment, mean trait score was 1.4 traits, and 7-year mean (SEM) change in trait score was +0.25 (0.02) traits, P<0.0001. In models with BMI predictors only, for every quintile difference in baseline BMI, the 7-year trait score increase was 0.14 traits, and for every quintile increase in BMI during 7-year follow-up, the trait score increased by 0.3 traits. Baseline level and change in fasting insulin were similarly related to trait score change. In models adjusted for age-sex-baseline cluster score, 7-year change in trait score was significantly related to both a 1-quintile difference in baseline BMI (0.07 traits) and fasting insulin (0.18 traits), and to both a 1-quintile 7-year increase in BMI (0.21 traits) and fasting insulin (0.18 traits).

CONCLUSIONS

Change in metabolic trait clustering was significantly associated with baseline levels and changes in both BMI and fasting insulin, highlighting the importance of both obesity and IR in the clustering of metabolic traits.

Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated guideline is to provide comprehensive and timely evidence-based recommendations on the prevention of future stroke among survivors of ischemic stroke or transient ischemic attack. The guideline is addressed to all clinicians who manage secondary prevention for these patients. Evidence-based recommendations are provided for control of risk factors, intervention for vascular obstruction, antithrombotic therapy for cardioembolism, and antiplatelet therapy for noncardioembolic stroke. Recommendations are also provided for the prevention of recurrent stroke in a variety of specific circumstances, including aortic arch atherosclerosis, arterial dissection, patent foramen ovale, hyperhomocysteinemia, hypercoagulable states, antiphospholipid antibody syndrome, sickle cell disease, cerebral venous sinus thrombosis, and pregnancy. Special sections address use of antithrombotic and anticoagulation therapy after an intracranial hemorrhage and implementation of guidelines.

Platelet activation: a link between psoriasis per se and subclinical atherosclerosis--a case-control study

BACKGROUND

Pathomechanisms of both psoriasis and atherosclerosis may involve platelet activation. Activated platelets show increased P-selectin; CD62 expression, and mean platelet volume (MPV). Impaired brachial artery flow-mediated dilatation (FMD) is related to atherosclerosis.

OBJECTIVES

To determine the presence of subclinical atherosclerosis in patients with psoriasis (without overt cardiovascular complications or traditional cardiovascular disease risk factors), compared with controls.

METHODS

In this case-control study, 25 patients with psoriasis and 25 age- and gender-matched healthy individuals were subjected to assessment of MPV, CD62 expression using flow cytometry, and brachial artery FMD and transthoracic echocardiography by cardiac ultrasound scanner.

RESULTS

A statistically highly significant increased CD62 expression, but not MPV, was found in cases compared with controls, and in patients with moderate/severe psoriasis compared with either mild cases or controls (P < 0.001). CD62 expression was statistically significantly positively correlated with the Psoriasis Area and Severity Index (PASI) score (P < 0.001), baseline brachial artery diameter (P = 0.03) but not FMD and aortic root diameter (ARD; P = 0.03). ARD was statistically significantly higher in patients with moderate/severe psoriasis compared with controls (P = 0.017). Stepwise simple linear regression analysis revealed that PASI score was the most important factor affecting CD62 expression (P < 0.001).

CONCLUSIONS

Our study showed increased atherosclerosis risk in patients with psoriasis, particularly those with moderate/severe disease, as evidenced by increased expression of platelet CD62 compared with healthy controls. Moreover, we found a positive correlation between CD62 expression and ARD (another possible marker of atherosclerosis), with positive correlation to the PASI score; the most important factor influencing CD62 expression. However, our data on MPV and FMD do not support the use of either value for diagnosing subclinical atherosclerosis in patients with psoriasis in further studies.

Effects of intermittent fasting on metabolism in men

This review analyzes the available literature on the impact of intermittent fasting (IF), a nutritional intervention, on different aspects of metabolism. The epidemic of metabolic disturbances, such as obesity, metabolic syndrome (MS), and diabetes mellitus type 2 has led to an increase in the prevalence of cardiovascular diseases, and affected patients might significantly benefit from modifications in nutritional habits. Recent experimental studies have elucidated some of the metabolic mechanisms involved with IF. Animal models have shown positive changes in glucose (lower plasma glucose and insulin levels) and in lipid metabolism (reduced visceral fat tissue and increased plasma adiponectin level), and an increased resistance to stress. Despite the limited number of samples studied, positive results have been reported on the impact of IF for human health. IF is reported to improve the lipid profile; to decrease inflammatory responses, reflected by changes in serum adipokine levels; and to change the expression of genes related to inflammatory response and other factors. Studies on obese individuals have shown that patient compliance was greater for IF than other traditional nutritional approaches (calorie restriction), and IF was found to be associated with low oxidative stress. Recent reports suggest that IF exerts a positive impact on the metabolic derangements commonly associated with cardiovascular diseases, and that it may be a viable and accessible intervention for most individuals. Therefore, further clinical studies are essential to test the effectiveness of IF in preventing and controlling metabolic and cardiovascular diseases.

Chronic migraine in women is associated with insulin resistance: a cross-sectional study

BACKGROUND AND PURPOSE

Migraine is a common neurological disorder. It can be divided into episodic migraine (EM) and chronic migraine (CM), based on headache frequency. Some studies have shown that insulin sensitivity is impaired in migraine; moreover, hypertension, diabetes and obesity are common in patients with CM. The aim of this study was to assess serum glucose, insulin levels and insulin resistance (IR) in a sample of episodic migraineurs, chronic migraineurs and non-pain healthy controls.

METHODS

Eighty-three women with EM, 83 with CM and 83 healthy controls were recruited. Headache was diagnosed according to the latest International Classification of Headache Disorders 2 criteria. Waist circumference, body mass index (BMI) and blood pressure were measured. Checked metabolic parameters included fasting glucose, the 2 h 75 g oral glucose tolerance test (2 h OGTT), serum HbA1c, blood lipid profile, C-reactive protein and prolactin. The homeostasis model assessment formula was used to calculate IR.

RESULTS

A significant prevalence of IR in CM was observed (P = 0.002). No significant associations were found with fasting glycaemia, the 2 h OGTT, HbA1c, blood lipid profile, C-reactive protein, prolactin and waist circumference. Obesity (BMI >30 kg/m(2)) was associated with an increased risk of CM [odds ratio (OR) 2.4]. When the outcome of interest was the association between IR and obesity, the OR was significantly increased compared with IR alone (OR = 13.2).

CONCLUSION

This may suggest that CM is associated with IR status, particularly when it is in partnership with obesity.

Psoriatic arthritis and diabetes: a population-based cross-sectional study

Background. Diabetes has been associated with psoriasis, but little is known about the association between psoriatic arthritis and diabetes. Methods. Patients diagnosed with psoriatic arthritis by a rheumatologist were compared to age- and sex-matched patients without psoriatic arthritis regarding the prevalence of diabetes in a population-based cross-sectional study using logistic multivariate models. The study was performed utilizing the medical database of Clalit, the largest healthcare provider organization in Israel. Results. The study included 549 patients with psoriatic arthritis ≥21 years and 1,098 patients without psoriatic arthritis. The prevalence of diabetes in patients with psoriatic arthritis was increased as compared to the prevalence in patients without psoriatic arthritis (15.3% versus 10.7%, P value = 0.008). The difference was prominent among females (18.7% versus 10.3%, P < 0.001) but not among males (11.2% in patients with and without psoriatic arthritis, P = 1.000). In a multivariate analysis, psoriatic arthritis was associated with diabetes among females (OR = 1.60, 95% CI: 1.02–2.52, P = 0.040) but not among males (OR = 0.71, 95% CI: 0.42–1.22, P = 0.213). Conclusion. Our study suggests a possible association between psoriatic arthritis and diabetes in women. Women with psoriatic arthritis might be candidates for diabetes screening.

High sensitivity C-reactive protein concentrations, birthweight and cardiovascular risk markers in Brazilian children

BACKGROUND/OBJECTIVES

High sensitivity C-reactive protein (hs-CRP) and low birthweight have emerged as predictors of cardiovascular diseases (CVDs). In studies involving adults, higher concentrations of hs-CRP have been associated with low birthweight. This study assessed the relationship between hs-CRP and birthweight, and other risk markers for CVDs in childhood.

SUBJECTS/METHODS

A total of 459 Brazilian children aged 5-8 years were included in the study. hs-CRP was measured by particle-enhanced immunonephelometry. The nutritional status of the children was assessed by BMI and waist circumference. Total cholesterol and fractions, triglycerides and glucose were measured by enzymatic methods. Insulin sensitivity was determined by the homeostasis model assessment (HOMA) method. Blood pressure was measured by the HDI/Pulse Wave CR-2000 equipment (Hypertension Diagnostics, Eagan, MN, USA). A multivariate linear regression analysis investigated the association between hs-CRP and birthweight, and risk markers for CVDs.

RESULTS

There were positive associations between hs-CRP and gender (P=0.001), waist circumference (P<0.001) and systolic blood pressure (SBP) (P=0.03), and negative associations between hs-CRP and age (P<0.001), and high-density lipoprotein cholesterol (HDL-c) (P=0.005) (R²=0.14). Abnormal values of hs-CRP, waist circumference, HDL-c and SBP, respectively, were observed in 27.7, 26.4, 14.4 and 34.7% of the children.

CONCLUSIONS

Opposite to studies involving adults, there was no association between hs-CRP and birthweight, implying that time may strengthen the relationship, considering that hs-CRP-concentration-associated metabolic changes increase from childhood to adulthood. The associations between hs-CRP and waist circumference, HDL-c and SBP in very young ages is a matter of concern, especially in females, in view of the large number of children with abnormal values of these measurements.

Pentamethylquercetin generates beneficial effects in monosodium glutamate-induced obese mice and C2C12 myotubes by activating AMP-activated protein kinase

AIMS/HYPOTHESIS

Pentamethylquercetin (PMQ) has recently been shown to have glucose-lowering properties. Here, we aimed to characterise the effectiveness and underlying mechanisms of PMQ for ameliorating metabolic disorders in vivo and vitro.

METHODS

We generated a mouse model of obesity by neonatal administration of monosodium glutamate (MSG) and used it to assess the properties of PMQ as a treatment for metabolic disorders. We also investigated the possible underlying mechanisms of PMQ in the prevention of metabolic disorders.

RESULTS

Compared with normal mice, MSG mice had metabolic disorders, including central obesity, hyperinsulinaemia, insulin resistance, hyperglycaemia, hyperlipidaemia, decreased phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), and downregulated levels of GLUT4 in gastrocnemius muscles. In MSG mice, PMQ treatment (5, 10, 20 mg/kg daily) reduced body weight gain, waist circumference, adipose tissue mass, serum glucose, triacylglycerol and total cholesterol, while improving insulin resistance, activating AMPK and increasing ACC phosphorylation and GLUT4 abundance. In C2C12 myotubes, PMQ (10 μmol/l) increased glucose consumption by ∼65%. PMQ treatment (1-10 μmol/l) also activated AMPK, increased ACC phosphorylation and GLUT4 abundance, and upregulated the expression of some key genes involved in fatty acid oxidation.

CONCLUSIONS/INTERPRETATION

These findings suggest that PMQ can ameliorate metabolic disorders at least in part via stimulation of AMPK activity.

Conventional and novel cardiovascular risk factors and markers of vascular damage in rural and urban Indian men

BACKGROUND

India is undergoing rapid epidemiological and nutritional transition largely as a consequence of rapid urbanisation. We investigated conventional and novel cardiovascular risk factors in rural and urban Indian men and studied their association with markers of vascular damage.

METHODS

We randomly selected and studied 149 rural, 142 urban slum residents and 150 urban middle class middle aged Indian men. We measured conventional (obesity, blood pressure, lipids, smoking habits) and novel (proinflammatory and prothrombotic factors) cardiovascular risk factors and markers of vascular damage (carotid intima media thickness (IMT), von Willebrand Factor (vWF), e-selectin).

RESULTS

There was a progressive increase in most of the conventional cardiovascular (CV) risk factors from rural to slum to urban middle class men. Plasminogen activator inhibitor-1 (PAI-1), platelet count, total homocysteine and C-reactive protein showed similar patterns. Carotid IMT was similar in the three groups; vWF was highest in rural and e-selectin in slum men. Adjusting for location, age explained 17%, obesity 3% and conventional risk factors 1% of the variance in carotid IMT, whilst novel cardiovascular risk factors were without any significant impact.

CONCLUSIONS

Urbanisation increases obesity related as well as prothrombotic and proinflammatory CV risk factors in Indian men, but appears not to impact on IMT.

Thermogenesis and related metabolic targets in anti-diabetic therapy

Exercise, together with a low-energy diet, is the first-line treatment for type 2 diabetes type 2 diabetes . Exercise improves insulin sensitivity insulin sensitivity by increasing the number or function of muscle mitochondria mitochondria and the capacity for aerobic metabolism, all of which are low in many insulin-resistant subjects. Cannabinoid 1-receptor antagonists and β-adrenoceptor agonists improve insulin sensitivity in humans and promote fat oxidation in rodents independently of reduced food intake. Current drugs for the treatment of diabetes are not, however, noted for their ability to increase fat oxidation, although the thiazolidinediones increase the capacity for fat oxidation in skeletal muscle, whilst paradoxically increasing weight gain.There are a number of targets for anti-diabetic drugs that may improve insulin sensitivity insulin sensitivity by increasing the capacity for fat oxidation. Their mechanisms of action are linked, notably through AMP-activated protein kinase, adiponectin, and the sympathetic nervous system. If ligands for these targets have obvious acute thermogenic activity, it is often because they increase sympathetic activity. This promotes fuel mobilisation, as well as fuel oxidation. When thermogenesis thermogenesis is not obvious, researchers often argue that it has occurred by using the inappropriate device of treating animals for days or weeks until there is weight (mainly fat) loss and then expressing energy expenditure energy expenditure relative to body weight. In reality, thermogenesis may have occurred, but it is too small to detect, and this device distracts us from really appreciating why insulin sensitivity has improved. This is that by increasing fatty acid oxidation fatty acid oxidation more than fatty acid supply, drugs lower the concentrations of fatty acid metabolites that cause insulin resistance. Insulin sensitivity improves long before any anti-obesity effect can be detected.

Increase in the prevalence of metabolic syndrome among workers according to age

INTRODUCTION

Statistical information regarding the prevalence of metabolic syndrome among a wide age range of workers is insufficient.

METHODS

A total of 4278 men between the ages of 20 and 59 years participated in the study. Metabolic syndrome was diagnosed according to the International Diabetes Federation (IDF) and the National Cholesterol Education Program (NCEP) III criteria.

RESULTS

Overall, the prevalences of metabolic syndrome according to the IDF and NCEPIII criteria were 13.6% and 14.8%, respectively. The prevalence of metabolic syndrome according to the IDF (NCEPIII) criteria among workers in their 20s, 30s, 40s, and 50s were 4.8% (6.1%), 9.9% (12.2%), 18.4% (21.6%) and 25.8% (34.0%), respectively. A plot of the prevalence of metabolic syndrome according to the NCEPIII criteria versus age had a steep gradient and increased sharply for men in their 50s. In contrast, a plot of the prevalence of metabolic syndrome according to the IDF criteria versus age increased in a linear manner.

CONCLUSION

The prevalence of metabolic syndrome increased among workers according to age, but the increasing trend and the absolute prevalence of metabolic syndrome differed according to the two sets of diagnostic criteria used in this study.

Assessment of insulin resistance by a 13C glucose breath test: a new tool for early diagnosis and follow-up of high-risk patients

Background/Aims

Insulin resistance (IR) plays an important role in the pathogenesis of diabetes and non-alcoholic fatty liver disease (NAFLD). Current methods for insulin resistance detection are cumbersome, or not sensitive enough for early detection and follow-up. The BreathID^® system can continuously analyse breath samples in real-time at the point-of-care. Here we determined the efficacy of the BreathID^® using the ¹³C-Glucose breath test (GBT) for evaluation of insulin resistance.

Methods

Twenty healthy volunteers were orally administered 75 mg of ¹³C-glucose 1-¹³C. An oral glucose tolerance test (OGTT) was performed immediately; followed by serum glucose and insulin level determinations using GBT. GBT and OGTT were repeated following exercise, which alters insulin resistance levels.

Results

Within-subject correlations of GBT parameters with serum glucose and serum insulin levels were high. Before and after exercise, between-subjects correlations were high between the relative insulin levels and the % dose recoveries at 90 min (PDR 90), and the cumulative PDRs at 60 min (CPDR 60). Pairwise correlations were identified between pre-exercise Homeostasis Model Assessment (HOMA) IR at 90 min and PDR 90; HOMA B (for beta cell function) 120 and CPDR 30; HOMA IR 60 and peak time post-exercise; and HOMA B 150 with PDR 150.

Conclusions

The non-invasive real-time BreathID^® GBT reliably assesses changes in liver glucose metabolism, and the degree of insulin resistance. It may serve as a non-invasive tool for early diagnosis and follow up of patients in high-risk groups.

Bean amylase inhibitor and other carbohydrate absorption blockers: effects on diabesity and general health

Many believe that excessive intake of refined carbohydrates (CHO) plays a major role in the development of obesity/overweight, type 2 diabetes mellitus and insulin resistance, a collection of events commonly referred to as "diabesity," and have sought natural means to overcome these linked perturbations. As a first approach, planned diets with low portions of refined CHO have become popular. However, these diets do not satisfy everyone; and many are concerned over replacing CHO with more fats. As a second option, addition of soluble fiber to the diet can slow absorption of refined CHO, i.e., lower the glycemic index of foods and overcome or at least ameliorate many of the adverse reactions resulting from increased refined CHO ingestion. Unfortunately, the general public does not favor diets high in fiber content, and various fibers can lead to gastrointestinal problems such as gas and diarrhea. A third choice to favorably influence CHO absorption is to use natural dietary supplements that block or slow CHO absorption in the gastrointestinal tract via inhibiting enzymes necessary for CHO absorption -amylase and alpha-glucosidases. Although a number of natural supplements with anti-amylase activity have been recognized, the most studied and favored one is white kidney bean extract. Animal and human studies clearly show that this agent works in vivo and has clinical utility. This paper reviews many aspects of diabesity and the use of "carb blockers" to prevent and ameliorate the situation. In many respects, carb blockers mimic the beneficial effects of fibers.

Adipose tissue at the crossroads in the development of the metabolic syndrome, inflammation and atherosclerosis

The authors analyze insulin resistance, the metabolic syndrome and endothelial dysfunction as consequence of a common antecedent, a low grade inflammation, indicating that in obesity there is a chronically activated inflammatory state of the adipose tissue. Furthermore, the inflammatory signaling is discussed according to the adipose tissue depot, visceral or subcutaneous.

Adipose tissue, inflammation and atherosclerosis

Metabolic syndrome is associated with dysfunctional adipose tissue that is most likely a consequence of the enlargement of adipocytes and infiltration of macrophages into adipose tissue. Obesity and ectopic lipid deposition are major risk factors for diseases ranging from insulin resistance to type 2 diabetes and atherosclerosis. Enlargement of adipocytes, due to impaired adipocyte differentiation, leads to a chronic state of inflammation in the adipocytes and adipose tissue with a reduction in the secretion of adiponectin and increase in the secretion of proinflammatory cytokines such as interleukin (IL)-6, IL-8 and monocyte chemoattractant protein (MCP)-1. The secretion of cytokines like tumour necrosis factor (TNF)- alpha, mainly from macrophages, enhances local inflammation. These proinflammatory cytokines might also substantially affect cardiovascular function and morphology. Furthermore, a proinflammatory state in adipose tissue can lead to local insulin resistance with an impaired inhibitory effect of insulin on the release of FFAs and endothelial dysfunction that clearly promotes cardiovascular diseases and type 2 diabetes. The underlying mechanisms of ectopic fat accumulation in various tissues and the impact on metabolic syndrome and its association with insulin resistance are discussed.

The relationship between birth weight and insulin resistance in childhood

Chronic diseases that are typical of adulthood may originate in intra-uterine life through inadequate fetal development. The present epidemiological cohort study of 506 healthy children aged 5–8 years evaluated the relationship between birth weight and insulin resistance in an age group that has been assessed in few similar studies. Insulin concentration was determined by chemiluminescence and insulin resistance by the homeostasis model assessment (HOMA). Blood glucose, total cholesterol and fractions (LDL cholesterol and HDL cholesterol) and TAG concentrations were determined by automated enzymatic methods. Linear regression analysis investigated the relationship between birth weight (assessed as a continuous variable and in three categories: small for gestational age, SGA; adequate for gestational age and large for gestational age) and the HOMA index, using backward stepwise selection and biological models to explain the causal pathway of the relationship. There were negative associations between birth weight (P < 0·001), SGA (P = 0·027) and the HOMA index, and a positive association between waist circumference (P < 0·001) and the HOMA index. Considering the significant associations between birth weight and waist circumference (P < 0·001) and waist circumference and insulin resistance (P < 0·001), we can probably suspect that lower birth weight is a common cause of higher waist circumference and insulin resistance. In summary, the results of the present study showed increased insulin resistance in apparently healthy, young children, who had lower weight at birth and higher measurements of waist circumference. There is a need to develop public health policies that adopt preventive measures to promote adequate maternal-fetal and child development and enable early diagnosis of metabolic abnormalities.

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

BACKGROUND

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation.

REVIEW

We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation).The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible.This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles.Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here.

CONCLUSION

Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets.

Relationship between birthweight and arterial elasticity in childhood

There is a considerable debate about the potential influence of ‘fetal programming’ on cardiovascular diseases in adulthood. In the present prospective epidemiological cohort study, the relationship between birthweight and arterial elasticity in 472 children between 5 and 8 years of age was assessed. LAEI (large artery elasticity index), SAEI (small artery elasticity index) and BP (blood pressure) were assessed using the HDI/PulseWave™ CR-2000 CardioVascular Profiling System. Blood concentrations of glucose, total cholesterol and its fractions [LDL (low-density lipoprotein)-cholesterol and HDL (high-density lipoprotein)-cholesterol] and triacylglycerols (triglycerides) were determined by automated enzymatic methods. Insulin was assessed by a chemiluminescent method, insulin resistance by HOMA (homoeostasis model assessment) and CRP (C-reactive protein) by immunonephelometry. Two linear regression models were applied to investigate the relationship between the outcomes, LAEI and SAEI, and the following variables: birthweight, gestational age, glucose, LDL-cholesterol, HDL-cholesterol, triacylglycerols, insulin, CRP, HOMA, age, gender, waist circumference, per capita income, SBP (systolic BP) and DBP (diastolic BP). LAEI was positively associated with birthweight (P=0.036), waist circumference (P<0.001) and age (P<0.001), and negatively associated with CRP (P=0.024) and SBP (P<0.001). SAEI was positively associated with birthweight (P=0.04), waist circumference (P=0.001) and age (P<0.001), and negatively associated with DBP (P<0.001). Arterial elasticity was decreased in apparently healthy children who had lower birthweights, indicating an earlier atherogenetic susceptibility to cardiovascular diseases in adolescence and adult life. Possible explanations for the results include changes in angiogenesis during critical phases of intrauterine life caused by periods of fetal growth inhibition and local haemodynamic anomalies as a way of adaptation to abnormal pressure and flow.

Impaired microvascular perfusion: a consequence of vascular dysfunction and a potential cause of insulin resistance in muscle

Insulin has an exercise-like action to increase microvascular perfusion of skeletal muscle and thereby enhance delivery of hormone and nutrient to the myocytes. With insulin resistance, insulin's action to increase microvascular perfusion is markedly impaired. This review examines the present status of these observations and techniques available to measure such changes as well as the possible underpinning mechanisms. Low physiological doses of insulin and light exercise have been shown to increase microvascular perfusion without increasing bulk blood flow. In these circumstances, blood flow is proposed to be redirected from the nonnutritive route to the nutritive route with flow becoming dominant in the nonnutritive route when insulin resistance has developed. Increased vasomotion controlled by vascular smooth muscle may be part of the explanation by which insulin mediates an increase in microvascular perfusion, as seen from the effects of insulin on both muscle and skin microvascular blood flow. In addition, vascular dysfunction appears to be an early development in the onset of insulin resistance, with the consequence that impaired glucose delivery, more so than insulin delivery, accounts for the diminished glucose uptake by insulin-resistant muscle. Regular exercise may prevent and ameliorate insulin resistance by increasing "vascular fitness" and thereby recovering insulin-mediated capillary recruitment.

Diabetes classification: grey zones, sound and smoke: Action LADA 1

Diseases gain identity from clinical phenotype as well as genetic and environmental aetiology. The definition of type 1 diabetes is clinically exclusive, comprising patients who are considered insulin dependent at diagnosis, whilst the definition of type 2 diabetes is inclusive, only excluding those who are initially insulin dependent. Ketosis-prone diabetes (KPD) and latent autoimmune diabetes in adults (LADA) are each exclusive forms of diabetes which are, at least initially, clinically distinct from type 2 diabetes and type 1 diabetes, and each have a different natural history from these major types of diabetes.KPD can be diagnosed unequivocally as diabetes presenting with the categorical clinical feature, ketoacidosis. In contrast, LADA can be diagnosed by the co-occurrence of three traits, not one of which is categorical or exclusive to the condition: adult-onset non-insulin-requiring diabetes, an islet autoantibody such as glutamic acid decarboxylase autoantibodies (GADA) or cytoplasmic islet cell autoantibodies (ICA), and no need for insulin treatment for several months post-diagnosis. But while some would split diabetes into distinct subtypes, there is a strong case that these subtypes form a continuum of varying severity of immune and metabolic dysfunction modified by genetic and non-genetic factors. This article discusses the nature of disease classification in general, and KPD and LADA in particular, emphasizing the potential value and pitfalls in classifying diabetes and suggesting a need for more research in this area.

Psoriasis and diabetes: a population-based cross-sectional study

BACKGROUND

Previous reports have shown an association between psoriasis and the metabolic syndrome, but there are only a few studies on the association between psoriasis and diabetes.

OBJECTIVES

To study the association between psoriasis and diabetes.

METHODS

A cross-sectional study was performed utilizing the database of Clalit Health Services (CHS). Patients who were diagnosed with psoriasis were compared with CHS enrolees without psoriasis regarding the prevalence of diabetes. Patients with diabetes were identified using the CHS chronic diseases registry. Chi-squared tests were used to compare categorical parameters. Logistic regression models were used for multivariate analyses.

RESULTS

The study included 16 851 patients with psoriasis and 74 987 subjects without psoriasis (control patients). The proportion of diabetes was significantly higher in patients above 35 years (P < 0.05). The age-adjusted proportion of diabetes was significantly higher in psoriasis patients as compared to the control group [odds ratio (OR), 1.38, P < 0.05] and was similar in men and women (OR, 1.32, 1.45, respectively). A multivariate logistic regression model showed that psoriasis was significantly associated with diabetes, independently of age and gender (OR, 1.58, P < 0.001).

CONCLUSIONS

Our study supports previous reports of an association between psoriasis and diabetes. Dermatologists taking care of patients with psoriasis should be aware of this association and advise the patients to reduce additional risk factors such as smoking, hypertension or dyslipidemia.

Acarbose: oral anti-diabetes drug with additional cardiovascular benefits

Acarbose is an alpha-glucosidase inhibitor acting specifically at the level of postprandial glucose excursion. This compound lowers HbA(1c) by 0.5-1% in patients with Type 2 diabetes, either drug naive or in combination with other antidiabetic drugs. In those with impaired glucose tolerance (IGT), it reduces the incidence of newly diagnosed diabetes by 36.4%. Furthermore, it has beneficial effects on overweight, reduces blood pressure and triglycerides, and downregulates biomarkers of low-grade inflammation. In the Study To Prevent Non-Insulin-Dependent-Diabetes-Mellitus (STOP-NIDDM) trial, acarbose significantly reduced the progression of intima media thickness, incidence of cardiovascular events and of newly diagnosed hypertension. In a meta-analysis of patients with Type 2 diabetes (MERIA), acarbose intake was associated with a reduction of cardiovascular events by 35%. Acarbose is a very safe drug but in approximately 30% of patients, it can cause gastrointestinal complaints due to its mode of action, which in the majority disappear after 1-2 months. Acarbose is approved for treatment of IGT in 25 countries. It can be given alone or in combination with other oral antidiabetics and insulin. Acarbose is particularly effective in those with IGT and early diabetes and patients with comorbidities of the metabolic syndrome.

Metabolic syndrome and endothelial fibrinolytic capacity in obese adults

The metabolic syndrome (MetS) often accompanies obesity and contributes to the increased risk of atherothrombotic events with increased body fatness. Indeed, the risks for coronary artery disease and acute vascular events are greater with obesity combined with MetS compared with obesity alone. Endothelial release of tissue-type plasminogen activator (t-PA) is a key defense mechanism against thrombosis and has been shown to be impaired with obesity. The aim of the present study was to determine whether the presence of MetS exacerbates endothelial fibrinolytic dysfunction in obese adults. Net endothelial release of t-PA was determined in vivo in response to intrabrachial infusions of bradykinin and sodium nitroprusside in 47 sedentary adults: 15 normal weight (age 57 +/- 2 yr; body mass index 22.9 +/- 0.5 kg/m(2)), 14 obese but otherwise healthy (55 +/- 1 yr; 29.4 +/- 0.3 kg/m(2)), and 18 obese with MetS (55 +/- 2 yr; 32.3 +/- 1 kg/m(2)). MetS was established according to National Cholesterol Education Program ATP III criteria. Net release of t-PA antigen to bradykinin was approximately 50% lower (P < 0.01) in the obese (from 2.5 +/- 1.9 to 37.1 +/- 5.3 ng.100 ml tissue(-1).min(-1)) and obese with MetS (from 0.4 +/- 0.8 to 32.5 +/- 3.8 ng.100 ml tissue(-1).min(-1)) compared with normal-weight (from 0.9 +/- 1.0 to 74.3 +/- 8.1 ng.100 ml tissue(-1).min(-1)) subjects. However, there were no significant differences in the capacity of the endothelium to release t-PA in the obese and obese with MetS adults. These results indicate that the presence of the MetS does not worsen the obesity-related endothelial fibrinolytic dysfunction.