Cdc2-like kinase 2 in the hypothalamus is necessary to maintain energy homeostasis

OBJECTIVE

To investigate whether the Cdc2-like kinase 2 (CLK2) is expressed in hypothalamic neurons and if it is, whether the hypothalamic CLK2 has a role in the regulation of energy balance.

SUBJECTS

Swiss mice on chow or high-fat diet (HFD) and db/db mice on chow diet were used to address the role of CLK2 in the hypothalamus.

RESULTS

Hypothalamic CLK2^Thr343 phosphorylation, which induces CLK2 activity, is regulated in vivo by refeeding, insulin and leptin, in a PI3K (phosphoinositide 3-kinase)-dependent manner. The reduction of CLK2 expression in the hypothalamus, by chronic pharmacological inhibition with TG003 or by chronic knockdown with small interfering RNA was sufficient to abolish the anorexigenic effect of insulin and leptin, to increase body weight, fat mass, food intake and to decrease energy expenditure in mice on chow. In contrast, CLK2^Thr343 phosphorylation in the hypothalamus in response to insulin, leptin or refeeding was impaired in mice on HFD or in db/db mice. Chronic CLK2 inhibition in the hypothalamus was associated with a slight increase in the fasting blood glucose levels, reduction in PEPCK (phosphoenolpyruvate carboxykinase) expression in the liver and enhanced glucose production from pyruvate, suggesting a regulation of hepatic glucose production. Further, overexpressing CLK2 in the mediobasal hypothalami of mice on HFD or in db/db mice by adenovirus partially reversed the obese phenotype.

CONCLUSIONS

Thus, our results suggest that protein CLK2 integrates some important hypothalamic pathways, and may be a promising molecule for new therapeutic approaches for obesity and diabetes.

Efficacy of Soybean's Event DAS-81419-2 Expressing Cry1F and Cry1Ac to Manage Key Tropical Lepidopteran Pests Under Field Conditions in Brazil

Bacillus thuringiensis (Bt) event DAS-81419-2 (Conkesta technology) in soybean, Glycine max (L.) Merrill, expresses Cry1F and Cry1Ac proteins to provide protection from feeding by several lepidopteran pests. A total of 27 field experiments across nine locations were conducted from 2011 to 2015 in southern and central Brazil to characterize the efficacy of DAS-81419-2 soybean infested with Anticarsia gemmatalis Hübner (Lepidoptera: Erebidae), Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae), Heliothis virescens (F.) (Lepidoptera: Noctuidae), and Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) during vegetative (V4) and reproductive (R2 and R4) crop developmental stages. The efficacy of DAS-81419-2 was compared to that of a non-Bt isogenic variety managed with or without applications of commercial foliar insecticides for lepidopteran control. DAS-81419-2 soybean consistently experienced defoliation levels of 0.5% or less (compared with 20.05-56.74% in the non-Bt, nonsprayed treatment) and larval survival of < 0.1% in all four species across the vegetative and reproductive plant stages evaluated. The efficacy of DAS-81419-2 was significantly higher than commercial foliar insecticides applied to the non-Bt variety. DAS-81419-2 soybeans containing two highly effective Bt proteins are expected to be a more robust IRM tool compared to single-trait Bt technologies. The consistent efficacy of DAS-81419-2 soybeans across years, locations, and crop stages suggests that it will be a valuable product for management of hard-to-control key lepidopteran pests in South American soybean production.

Sporadic Creutzfeldt-Jakob disease diagnostic accuracy is improved by a new CSF ELISA 14-3-3γ assay

Protein 14-3-3 is a reliable marker of rapid neuronal damage, specifically increased in cerebrospinal fluid (CSF) of sporadic Creutzfeldt-Jakob disease (sCJD) patients. Its detection is usually performed by Western Blot (WB), prone to methodological issues. Our aim was to evaluate the diagnostic performance of a recently developed quantitative enzyme-linked immunosorbent (ELISA) assay for 14-3-3γ, in comparison with WB and other neurodegeneration markers. CSF samples from 145 patients with suspicion of prion disease, later classified as definite sCJD (n=72) or Non-prion diseases (Non-CJD; n=73) comprised our population. 14-3-3 protein was determined by WB and ELISA. Total Tau (t-Tau) and phosphorylated Tau (p-Tau) were also evaluated. Apolipoprotein E gene (ApoE) and prionic protein gene (PRNP) genotyping was assessed. ELISA 14-3-3γ levels were significantly increased in sCJD compared to Non-CJD patients (p<0.001), showing very good accuracy (AUC=0.982; sensitivity=97%; specificity=94%), and matching WB results in 81% of all cases. It strongly correlated with t-Tau and p-Tau (p<0.0001), showing slightly higher specificity (14-3-3 WB - 63%; Tau - 90%; p-Tau/t-Tau ratio - 88%). From WB inconclusive results (n=44), ELISA 14-3-3γ correctly classified 41 patients. Additionally, logistic regression analysis selected ELISA 14-3-3γ as the best single predictive marker for sCJD (overall accuracy=93%). ApoE and PRNP genotypes did not influence ELISA 14-3-3γ levels. Despite specificity for 14-3-3γ isoform, ELISA results not only match WB evaluation but also help discrimination of inconclusive results. Our results therefore reinforce this assay as a single screening test, allowing higher sample throughput and unequivocal results.

Prevalence of 35delG and Met34Thr GJB2 variants in Portuguese samples

OBJECTIVE

To estimate the prevalence of 35delG and Met34Thr variants in a Portuguese children's community sample and to compare these frequencies with nonsyndromic hearing-loss patients.

METHODS

502 children were randomly selected among the 8647 participants of the Portuguese birth cohort Generation XXI, and screened for Met34Thr and 35delG variants in the GJB2 gene. These variants were also studied on 89 index-cases, observed in the Clinic of "Hereditary Hearing-loss" in Saint John's Hospital Center, presenting a mild to profound nonsyndromic hearing-loss.

RESULTS

Among the 502 children from Generation XXI, 10 were heterozygous for the 35delG variant (95% Confidence Interval 1.03-3.68) and 1 homozygous (95% Confidence Interval 0.01-1.24). Other 10 children presented heterozygosity for the Met34Thr variant (95% Confidence Interval 1.03-3.68). No homozygous for the Met34Thr or compound heterozygotes (35delG/Met34Thr) were found. In the total of 89 nonsyndromic hearing-loss patients, 5 (95% Confidence Interval 2.11-12.8) were heterozygous and 7 (95% Confidence Interval 3.61-15.6) were homozygous for the 35delG variant. The Met34Thr variant was found in 4 patients, 2 heterozygous (95% Confidence Interval 0.13-8.31) and 2 homozygous (95% Confidence Interval 0.13-8.31).

CONCLUSION

The carrier frequency of 35delG and Met34Thr variants in a Portuguese sample was 1 in 50. Our data suggests that the 35delG mutation has an association with deafness. For the Met34Thr variant, no association was observed. However, Met34Thr seemed to conform to an additive model in hearing-loss.

A new approach to estimating weight change and its reference intervals during the first 96 hours of life

AIM

We aimed to apply a novel model to estimate weight change and its reference intervals during the first 96 h of life and the time of weight nadir.

METHODS

This study involved 1288 full-term singletons, from the Generation XXI birth cohort. Recruitment occurred between 2005 and 2006 in all five public units providing obstetrical and neonatal care in Porto, Portugal. Birthweight was abstracted from clinical records, and the subsequent newborn anthropometrics were obtained by trained examiners. Longitudinal models to estimate postnatal weight were tested and the weight ratio was calculated as the weight during 96 h of life divided by birthweight.

RESULTS

The chosen model was (weight(t)~ 3241.442 + (-9.378) × t + 0.119 × t(2) + 0.000 × t(3) + b0i + b1i × t, where t represented the newborn infant's age in hours and bi represented the random coefficients. The curve inflection point (nadir) was achieved at 52.3 h of life, corresponding to a loss of 218 g and a weight ratio of 0.933. We estimated that at six, 12, 24 and 36 h of life the mean weight ratio and 10th-90th percentiles were 0.978 (0.968-0.988), 0.968 (0.953-0.983), 0.951 (0.928-0.974) and 0.939 (0.909-0.969), respectively.

CONCLUSION

This model allows a more accurate estimate of newborn weight change and its reference intervals, and estimated the nadir at 52.3 h of life, corresponding to a weight ratio of 0.933.

Pioglitazone treatment increases food intake and decreases energy expenditure partially via hypothalamic adiponectin/adipoR1/AMPK pathway

INTRODUCTION

Thiazolidinediones (TZDs) enhanced body weight (BW) partially by increased adipogenesis and hyperphagia. Neuronal PPARγ knockout mice on high-fat diet (HFD) are leaner because of enhanced leptin response, although it could be secondary to their leanness. Thus, it still is an open question how TZDs may alter energy balance. Multiple factors regulate food intake (FI) and energy expenditure (EE), including anorexigenic hormones as insulin and leptin. Nonetheless, elevated hypothalamic AMPK activity increases FI and TZDs increase AMPK activity in muscle cells. Thus, the aim of the present study was to investigate whether Pioglitazone (PIO) treatment alters hypothalamic insulin and leptin action/signaling, AMPK phosphorylation, and whether these alterations may be implicated in the regulation of FI and EE.

METHODS

Swiss mice on HFD (2 months) received PIO (25 mg kg(-1) per day-gavage) or vehicle for 14 days. AMPK and AdipoR1 were inhibited via Intracerebroventricular injections using Compound C (CompC) and small interference RNA (siRNA), respectively. Western blot, real-time PCR and CLAMS were done.

RESULTS

PIO treatment increased BW, adiposity, FI, NPY mRNA and decreased POMC mRNA expression and EE in HFD mice. Despite higher adiposity, PIO treatment improved insulin sensitivity, glucose tolerance, decreased insulin and increased adiponectin serum levels. This result was associated with, improved insulin and leptin action/signaling, decreased α2AMPK(Ser491) phosphorylation and elevated Acetyl-CoA carboxylase and AMPK(Thr172) phosphorylation in hypothalamus. The inhibition of hypothalamic AMPK with CompC was associated with decreased adiposity, FI, NPY mRNA and EE in PIO-treated mice. The reduced expression of hypothalamic AdipoR1 with siRNA concomitantly with PIO treatment reverted PIO induced obesity development, suggesting that adiponectin may be involved in this effect.

CONCLUSIONS

These results demonstrated that PIO, despite improving insulin/leptin action in hypothalamus, increases FI and decreases EE, partially, by activating hypothalamic adiponectin/AdipoR1/AMPK axis. Suggesting a novel mechanism in the hypothalamus by which TZDs increase BW.

IL-4 and IL-6 levels and adipose tissue distribution in HIV-1 patients under antiretroviral therapy

PURPOSE

Combined antiretroviral therapy (cART) for the treatment of HIV-1 infection has been associated with complications, including lipodystrophy. Several interleukins have been implicated in the pathology and physiology of lipodystrophy. The present study aimed to compare the levels of IL-4 and IL-6 in HIV-1 patients under cART with and without, clinically and fat mass ratio defined, lipodystrophy and in four different groups of fat distribution: (1) no lipodystrophy; (2) isolated central fat accumulation; (3) isolated lipoatrophy and (4) mixed forms of lipodystrophy.

METHODS

In the present cross-sectional study we evaluated IL-4 and IL-6 levels, insulin resistance and insulin sensitivity indexes in 86 HIV-infected adults under cART.

RESULTS

No significant differences in IL-4 and IL-6 levels between the four groups of body composition were observed. Patients with HOMA-IR >4 presented higher levels of IL-6 and lower levels of IL-4, although without statistical significance. No correlation between IL-6, or IL-4, HOMA-IR and quantitative body fat mass distribution was found.

CONCLUSION

Although there was a tendency for patients with isolated lipoatrophy and isolated fat accumulation to present higher IL-6 levels, these differences were not statistically significant. No differences were found relating IL-4 levels.

Healthy excessive weight in Portuguese women 4 years after delivery of a liveborn

OBJECTIVE

To quantify the prevalence of healthy excessive weight and determinants of metabolic profile, considering women's reproductive life.

METHODS

We evaluated 1847 mothers of a birth cohort assembled after delivery and reevaluated 4years later. A healthy profile was defined as the absence of hypertension, diabetes, dyslipidemia, C-reactive protein <3mg/l and being below the second tertile of HOMA-IR. Adjusted odds ratios (OR) and confidence intervals (95% CI) were computed using multinomial logistic regression, taking women with normal BMI as the reference category of the outcome.

RESULTS

Four years after delivery, 47% of women had normal BMI, 33% were overweight and 20% obese. In each BMI class, 61%, 33% and 12% presented a healthy metabolic profile, respectively. Family history of CVD/cardiometabolic risk factors was associated with a higher probability of obesity with a not healthy metabolic profile (OR=1.39 95% CI: 0.98-1.98). Women who breastfed the enrolled child for >26weeks and practiced physical exercise were less likely to be obese and metabolically unhealthy (OR=0.39 95% CI: 0.23-0.68; OR=0.48 95% CI: 0.33-0.70, respectively), with no effect on healthy excessive weight.

CONCLUSIONS

These results support the existence of a healthy excessive weight phenotype in women after motherhood, influenced by anthropometrics, genetic and lifestyles characteristics.

Persistent organic pollutant levels in human visceral and subcutaneous adipose tissue in obese individuals--depot differences and dysmetabolism implications

BACKGROUND

The role of persistent organic pollutants (POPs) with endocrine disrupting activity in the aetiology of obesity and other metabolic dysfunctions has been recently highlighted. Adipose tissue (AT) is a common site of POPs accumulation where they can induce adverse effects on human health.

OBJECTIVES

To evaluate the presence of POPs in human visceral (vAT) and subcutaneous (scAT) adipose tissue in a sample of Portuguese obese patients that underwent bariatric surgery, and assess their putative association with metabolic disruption preoperatively, as well as with subsequent body mass index (BMI) reduction.

METHODS

AT samples (n=189) from obese patients (BMI ≥ 35) were collected and the levels of 13 POPs were determined by gas chromatography with electron-capture detection (GC-ECD). Anthropometric and biochemical data were collected at the time of surgery. BMI variation was evaluated after 12 months and adipocyte size was measured in AT samples.

RESULTS

Our data confirm that POPs are pervasive in this obese population (96.3% of detection on both tissues), their abundance increasing with age (RS=0.310, p<0.01) and duration of obesity (RS=0.170, p<0.05). We observed a difference in AT depot POPs storage capability, with higher levels of ΣPOPs in vAT (213.9 ± 204.2 compared to 155.1 ± 147.4 ng/g of fat, p<0.001), extremely relevant when evaluating their metabolic impact. Furthermore, there was a positive correlation between POP levels and the presence of metabolic syndrome components, namely dysglycaemia and hypertension, and more importantly with cardiovascular risk (RS=0.277, p<0.01), with relevance for vAT (RS=0.315, p<0.01). Finally, we observed an interesting relation of higher POP levels with lower weight loss in older patients.

CONCLUSION

Our sample of obese subjects allowed us to highlight the importance of POPs stored in AT on the development of metabolic dysfunction in a context of obesity, shifting the focus to their metabolic effects and not only for their recognition as environmental obesogens.

Carotid intima media thickness is associated with body fat abnormalities in HIV-infected patients

BACKGROUND

HIV-infected patients may be at increased risk of cardiovascular (CV) events, and lipodystrophy is generally associated with proatherogenic metabolic disturbances. Carotid intima-media thickness (cIMT) has been used as a surrogate marker for atherosclerosis and it has been shown to be an independent risk factor for CV disease. Our objective was to evaluate cIMT in HIV-infected patients on combined anti-retroviral therapy (cART) with and without lipodystrophy defined by fat mass ratio (L-FMR), and to determine the association of lipodystrophy and visceral obesity [(visceral (VAT), subcutaneous adipose tissue (SAT) volume and VAT/SAT ratio, objectively evaluated by CT scan] with cIMT.

METHODS

Cross-sectional study of 199 HIV-infected patients. Body composition by DXA and abdominal CT, lipids, blood pressure, inflammatory markers, and cIMT by ultrasonography were performed. L-FMR was defined as the ratio of the percentage of trunk fat mass to the percentage of lower limb fat mass by DXA. Categorical variables were compared using the chi-square or Fisher's exact test. Spearman correlation coefficients were estimated to study the association between cIMT and clinical and metabolic characteristics. Means of cIMT, adjusted for age, were calculated, using generalized linear models.

RESULTS

L-FMR was present in 41.2% of patients and cIMT was higher in these patients [0.81 (0.24) vs. 0.76 (0.25); p=0.037)]. Lipodystrophic patients had higher VAT and VAT/SAT ratio and lower SAT. cIMT was associated with lipodystrophy evaluated by FMR, trunk fat, total abdominal fat, VAT and VAT/SAT ratio. No association was observed between cIMT and leg fat mass. Using generalized linear models, cIMT means were adjusted for age and no significant differences remained after this adjustment. The adjusted mean of cIMT was 0.787 (95%CI: 0.751-0.823) in patients without lipodystrophy, and 0.775 (95%CI: 0.732-0.817) in those with lipodystrophy (p=0.671).

CONCLUSIONS

HIV-infected patients on cART with lipodystrophy defined by FMR, had a significantly higher cIMT. Carotid IMT was also associated with classical cardiovascular risk factors. In these patients, visceral adipose tissue had a significant impact on cIMT, although age was the strongest associated factor.

Adipokines, hormones related to body composition, and insulin resistance in HIV fat redistribution syndrome

Background

Lipodystrophies are characterized by adipose tissue redistribution, insulin resistance (IR) and metabolic complications. Adipokines and hormones related to body composition may play an important role linking these alterations. Our aim was to evaluate adipocyte-derived hormones (adiponectin, leptin, resistin, TNF-α, PAI-1) and ghrelin plasma levels and their relationship with IR in HIV-infected patients according to the presence of lipodystrophy and fat redistribution.

Methods

Anthropometric and metabolic parameters, HOMA-IR, body composition by DXA and CT, and adipokines were evaluated in 217 HIV-infected patients on cART and 74 controls. Fat mass ratio defined lipodystrophy (L-FMR) was defined as the ratio of the percentage of the trunk fat mass to the percentage of the lower limb fat mass by DXA. Patient’s fat redistribution was classified into 4 different groups according the presence or absence of either clinical lipoatrophy or abdominal prominence: no lipodystrophy, isolated central fat accumulation (ICFA), isolated lipoatrophy and mixed forms (MXF). The associations between adipokines levels and anthropometric, metabolic and body composition were estimated by Spearman correlation.

Results

Leptin levels were lower in patients with FMR-L and isolated lipoatrophy, and higher in those with ICFA and MXF. Positive correlations were found between leptin and body fat (total, trunk, leg, arm fat evaluated by DXA, and total, visceral (VAT), subcutaneous adipose tissue (SAT), and VAT/SAT ratio evaluated by CT) regardless of FMR-L, and with HOMA-IR only in patients with FMR-L. Adiponectin correlated negatively with VAT, and its mean levels were lower in patients with ICFA and higher in those with no lipodystrophy. Resistin was not correlated with adipose tissue but positively correlated with HOMA-IR in FMR-L patients. PAI-1 levels were higher in MXF-patients and their levels were positively correlated with VAT in those with FMR-L. Ghrelin was higher in HIV-infected patients than controls despite BMI-matching.

Conclusion

The overall body fat reduction in HIV lipoatrophy was associated with low leptin plasma levels, and visceral fat accumulation was mainly associated with decreased plasma levels of adiponectin.

Cortical thinning of the right anterior cingulate cortex in spider phobia: a magnetic resonance imaging and spectroscopy study

There a lack of consistent neuroimaging data on specific phobia (SP) and a need to assess volumetric and metabolic differences in structures implicated in this condition. The aim of this study is investigate possible metabolic (via (1)H MRS) and cortical thickness abnormalities in spider-phobic patients compared to healthy volunteers. Participants were recruited via public advertisement and underwent clinical evaluations and MRI scans. The study started in 2010 and the investigators involved were not blind in respect to patient groupings. The study was conducted at the Ribeirão Preto Medical School University Hospital of the University of São Paulo, Brazil. Patients with spider phobia (n=19) were matched to 17 healthy volunteers with respect to age, education and socio-economic status. The spider SP group fulfilled the diagnostic criteria for spider phobia according to the Structured Clinical Interview for DSM-IV. None of the participants had a history of neurological, psychiatric or other relevant organic diseases, use of prescribed psychotropic medication or substance abuse. All imaging and spectroscopy data were collected with a 3 T MRI scanner equipped with 25 mT gradient coils in 30-minute scans. The Freesurfer image analysis package and LC Model software were used to analyze data. The hypothesis being tested was formulated before the data collection (neural correlates of SP would include the amygdala, insula, anterior cingulate gyrus and others). The results indicated the absence of metabolic alterations, but thinning of the right anterior cingulate cortex (ACC) in the SP group when compared to the healthy control group (mean cortical thickness±SD: SP=2.11±0.45 mm; HC=2.16±0.42 mm; t (34)=3.19, p=0.001 [-35.45, 71.00, -23.82]). In spectroscopy, the ratios between N-acetylaspartate and creatine and choline levels were measured. No significant effect or correlation was found between MRS metabolites and scores in the Spider Phobia Questionnaire and Beck Anxiety Inventory (p>0.05). The ACC is known to be related to the cognitive processing of fear and anxiety and to be linked with the conditioning circuit. The MRS findings are preliminary and need more studies. The finding of reduced ACC thickness in SP is in agreement with evidence from previous functional neuroimaging studies and highlights the importance of this brain area in the pathophysiology of SP.

Determinants of weight changes during the first 96 hours of life in full-term newborns

BACKGROUND

Newborn weight loss (NWL) in the first 3 days of life is around 6 percent of birthweight (BW). We aim to describe the determinants of an excessive and insufficient NWL in the first 96 hours of life.

METHODS

A sample of 1,288 full-term singletons without congenital abnormality belonging to Generation XXI birth cohort was selected. Newborns were recruited in 2005-2006 at all public units providing obstetrical and neonatal care in Porto, Portugal. Information was collected by face-to-face interview and additionally abstracted from clinical records. Anthropometrics were obtained by trained examiners and newborn weight change (NWC) was estimated as (weight-BW)/BW × 100. We categorized NWL as excessive (below 10th percentile of the sample distribution of NWC: ≤-9.4% of BW), normal (between 10th and 90th percentiles: -9.3 to -4.2%) and insufficient (above 90th percentile: ≥ -4.1%). Adjusted odds ratios (OR) and 95 percent confidence intervals (CI) were calculated using multinomial regression models.

RESULTS

Excessive NWL was positively associated with maternal age ≥40 years (OR = 3.32, 95%CI 1.19-9.25), maternal education (OR = 1.04, 95% CI 1.00-1.09), cesarean delivery (OR = 2.42, 95% CI 1.12-5.23), and phototherapy-treated jaundice (OR = 1.69, 95% CI 1.00-2.87). Insufficient NWL was positively associated with low BW (OR = 2.68, 95% CI 1.13-6.33), and formula/mixed feeding (OR = 1.74, 95% CI 1.13-2.66).

CONCLUSION

Excessive NWL was positively associated with maternal age and education, cesarean delivery, and phototherapy-treated jaundice. Insufficient NWL reflected child's feeding. As breastfed newborns did not lose weight excessively, but newborns with formula/mixed feeding had insufficient NWL, our study supports that breastfeeding provides excellent nutrition during this period.

Cardiovascular risk profile of mothers of a Portuguese birth cohort: a survey 4 years after delivery

OBJECTIVES

The aim of this study is to estimate the prevalence of smoking, low fruit and vegetable intake, sedentariness, overweight/obesity, abdominal obesity, hypertension, dyslipidemia and diabetes mellitus in mothers of a Portuguese birth cohort, 4 years after delivery.

METHODS

A birth cohort was assembled at public maternities of Porto (2005-2006). Children and mothers were reevaluated 4 years later. In this analysis, 5435 women were included. Socioeconomic characteristics, smoking, diet and exercise were self-reported. Anthropometrics and blood pressure were measured. A subgroup of 2483 randomly selected women provided a fasting venous blood sample for lipid and glucose measurements.

RESULTS

Overall, 25.3% women smoked, 71.5% consumed <5 portions of fruit and vegetables per day, 81.3% were sedentary, 31.4% were overweight, 21.3% obese and 31.8% had abdominal obesity. The prevalence of hypertension, dyslipidemia and diabetes mellitus was 8.7%, 18.5% and 0.9%, respectively. At least one risk factor from each of the 3 groups (adverse lifestyles, adiposity and cardiometabolic comorbidities) was observed in 17.4% of women. Except for smoking, all risk factors were associated with unemployment, lower education and lower income.

CONCLUSIONS

The high prevalence of unfavorable lifestyles and adiposity, and the aggregation of risk factors emphasize the adverse cardiovascular risk profile at a young age.

Linear spline multilevel models for summarising childhood growth trajectories: A guide to their application using examples from five birth cohorts

Childhood growth is of interest in medical research concerned with determinants and consequences of variation from healthy growth and development. Linear spline multilevel modelling is a useful approach for deriving individual summary measures of growth, which overcomes several data issues (co-linearity of repeat measures, the requirement for all individuals to be measured at the same ages and bias due to missing data). Here, we outline the application of this methodology to model individual trajectories of length/height and weight, drawing on examples from five cohorts from different generations and different geographical regions with varying levels of economic development. We describe the unique features of the data within each cohort that have implications for the application of linear spline multilevel models, for example, differences in the density and inter-individual variation in measurement occasions, and multiple sources of measurement with varying measurement error. After providing example Stata syntax and a suggested workflow for the implementation of linear spline multilevel models, we conclude with a discussion of the advantages and disadvantages of the linear spline approach compared with other growth modelling methods such as fractional polynomials, more complex spline functions and other non-linear models.

The development and validation of the Portuguese risk score for detecting type 2 diabetes and impaired fasting glucose

AIMS

To develop and validate a non-invasive score for detecting undiagnosed impaired fasting glucose (IFG) and type 2 diabetes (T2DM) in a Portuguese population.

METHODS

We used data from 3,374 individuals aged 18-94 years from a Portuguese cross-sectional study. We developed a logistic regression model for predicting IFG/T2DM (diagnosed using fasting glucose). We externally validated the score using data from two cohorts of the EPI-Porto study, cross-sectional (n = 2,131) and data from the 5 year follow-up (n = 1,304).

RESULTS

The final model included age, sex, BMI and hypertension with an area under the ROC curve of 70.1 (95%CI 68.4, 71.7). Using a cut-point which classifies 50% of the EPI-Porto cross-sectional data as high-risk gave sensitivity 73.2% (95%CI 68.5%, 77.6%), specificity 55.5% (53.1%, 57.8%), positive predictive value (PPV) 27.0% (24.3%, 29.8%) and negative predictive value (NPV) 90.2% (88.3%, 92.0%) for IFG/T2DM. Using the same cut-point on the prospective data classified 45% as high-risk; sensitivity 69.1% (63.4%, 74.4%), specificity 63.3% (60.0%, 66.5%), PPV 38.0% (33.9%, 42.4%), and NPV 86.2% (83.3%, 88.8%).

CONCLUSION

The Portuguese risk score can be used to identify those at high risk of both prevalent undiagnosed and incident IFG/T2DM.

Caffeic acid phenethyl ester protects against the dopaminergic neuronal loss induced by 6-hydroxydopamine in rats

Caffeic acid phenethyl ester (CAPE) is a botanical compound abundant in honeybees' propolis. It has anti-inflammatory, antiviral, antioxidant, immunomodulatory and antitumor properties. Its beneficial effects against neurodegenerative diseases, including Parkinson's disease, have also been suggested and some mechanisms have been proposed. Mitochondrial damage and oxidative stress are critical events in neurodegeneration. Release of cytochrome c from mitochondria to cytosol and the downstream activation of caspase-3 have been suggested as targets of the protective mechanism of CAPE. Most of the studies addressing the protective effect of CAPE have been performed in cell culture. This is the first study to demonstrate the protective effect of CAPE against the dopaminergic neuronal loss induced by 6-hydroxydopamine (6-OHDA) in rats. It also demonstrates, for the first time, the inhibitory effect of CAPE on mitochondrial permeability transition (MPT), a mediator of neuronal death that triggers cytochrome c release and caspase-3 activation. Scavenging of reactive oxygen species (ROS) and metal chelation was demonstrated in the brain-affected areas of the rats treated with 6-OHDA and CAPE. Additionally, we demonstrated that CAPE does not affect brain mitochondrial function. Based on these findings and on its ability to cross the blood-brain barrier, CAPE is a promising compound to treat Parkinson's and other neurodegenerative diseases.

Prevalence of obesity and its relationship to clinical lipodystrophy in HIV-infected adults on anti-retroviral therapy

BACKGROUND

Combination antiretroviral therapy (cART) is associated with lipodystrophy (lipoatrophy and lipoaccumulation) and several metabolic abnormalities that together can contribute to an increased cardiovascular risk. The aim of this study was to evaluate the prevalence of obesity in patients on cART according to the presence of clinical lipodystrophy (CL) and to analyze factors associated with obesity.

METHODS

We evaluated 368 HIV-infected adults on cART.

RESULTS

CL was present in 59.0%. Independently of gender, patients with CL were more frequently underweight [5.7% (21/368)] and of normal weight [47.3% (174/368)], and less frequently overweight [33.2% (122/368)] or obese [13.9% (51/368)]. Mean body mass index was higher in patients with abdominal prominence regardless of the presence of clinical lipoatrophy. Patients with CL had lower waist circumference, higher waist/hip and fat mass ratio and lower total and subcutaneous fat, without significant difference in visceral fat but with a higher visceral/subcutaneous fat ratio, as evaluated by CT at abdominal level. CL was significantly less frequent in overweight [odds ratio (OR)=0.21, 95% confidence interval (CI): 0.05-0.92] and obese (OR=0.05, 95%CI: 0.01-0.26) patients, when compared to underweight ones, independent of age, gender, duration of infection, cART regimen, virological suppression, and HIV-infection risk factor.

CONCLUSIONS

Being overweight or obese is highly prevalent in HIV-infected patients on cART. Patients with CL were more frequently under- or normal weight, and less frequently overweight or obese. Obesity is a condition that should be considered in HIV patients on cART.

Association between dietary patterns and metabolic syndrome in a sample of Portuguese adults

BACKGROUND

There is scarce evidence regarding the association between diet and metabolic syndrome (MetS) in Portuguese population. We aim to evaluate the association between a posteriori dietary patterns (DPs) and MetS and its features.

METHODS

Using random digit dialing, a sample of 2167 adults was selected between 1999 and 2003, in Porto. During a face-to-face interview, a questionnaire was applied, anthropometric measures were taken, blood pressure measured and a fasting blood sample collected. Diet was assessed using a validated food frequency questionnaire, and four DPs were identified in each sex by multivariate finite mixture models.

RESULTS

After adjustment for age and daily energy intake, comparing to the "healthy" DP, women with the "low fruit and vegetables" DP had a higher odds of high waist circumference (OR = 1.88 95% CI 1.17-3.01) and low HDL-cholesterol (OR = 1.78 95% IC 1.12-2.82) and women in the "red meat and alcohol" DP had higher odds of high waist circumference (OR = 1.45 95% CI 1.01-2.07) and of MetS (OR = 1.57 95% CI 1.07-2.29); men with the "fish" DP had a higher odds of high triglycerides (OR = 1.57 95% CI 1.05-2.35). After further adjustments (education, physical activity, smoking, alcohol drinking, BMI, and menopausal status) no significant associations remained.

CONCLUSIONS

Four distinct DPs were identified in a community sample of Portuguese adults and there was no association with the prevalence of MetS.

Lipodystrophy defined by Fat Mass Ratio in HIV-infected patients is associated with a high prevalence of glucose disturbances and insulin resistance

INTRODUCTION

Combined antiretroviral therapy (cART) in the treatment of HIV-1 infection has been associated with complications, including lipodystrophy, hyperlipidaemia, insulin resistance (IR) and diabetes.

AIMS

To compare the prevalence of glucose homeostasis disturbances and IR in HIV patients on cART according to the presence of lipodystrophy (defined clinically and by Fat Mass Ratio) and different patterns of fat distribution and to establish their associations.

DESIGN

Cross-sectional cohort study.

METHODS

We evaluated body composition and IR and insulin sensitivity indexes in 345 HIV-infected adults.

RESULTS

Patients with clinical lipodystrophy (CL) had higher plasma glucose levels than patients without CL, without significant differences in plasma insulin levels, A1c, HOMA-IR, HOMA-B, QUICKI, or MATSUDA index. Patients with lipodystrophy defined by FMR had higher plasma glucose and insulin levels, A1c, HOMA-IR, QUICKI and MATSUDA than patients without lipodystrophy, without differences in HOMA-B. Higher insulin resistance (HOMA-IR ≥ 4) was present in patients with FMR-defined lipodystrophy. Patients with FMR-defined lipodystrophy had a higher prevalence of IFG, IGT and DM than patients without lipodystrophy. Significant associations between HOMA-IR and total, central and central/peripheral fat evaluated by CT at abdominal level were found and no association between HOMA-IR and peripheral fat. Association between HOMA-IR and total and trunk fat but no association with leg and arm fat (evaluated by DXA) was found.

CONCLUSIONS

IR and glucose disturbances were significantly increased in patients with FMR-defined lipodystrophy. FMR lipodystrophy definition seems to be a more sensitive determinant of insulin resistance and glucose disturbances than clinical definition.