Acute and adaptive motor responses to caffeine in adolescent and adult rats

Gamma aminobutyric acid (GABA)-A receptor modulators constitute the majority of clinically relevant sedative-hypnotics. Zolpidem (Ambien) is a nonbenzodiazepine GABA-A receptor modulator that binds with high affinity to GABA-A receptors expressing alpha-1 subunits. The present study examined the effects of a new approach to the oral administration of zolpidem on locomotor activity, body weight, food intake, relative food intake, feed efficiency, anxiety, and visceral adiposity in rats. Effects of withdrawal associated with cessation of the drug were also recorded. A daily chronically administered oral 10 mg/kg dose of zolpidem caused a decrease in locomotor activity, an increase in food intake and relative food intake, and a more positive feed efficiency during the drug-administration period. Anxiety and visceral adiposity also increased in animals receiving the drug. During withdrawal of zolpidem, there was a decrease in body weight, food intake, relative food intake, and anxiety, as well as a negative feed efficiency. These results suggest that zolpidem can modulate locomotor activity, metabolism, and anxiety-related behavior. A highly positive feed efficiency and increased visceral adiposity associated with zolpidem intake were unique findings of this study.     

Association of plasma markers of cholesterol homeostasis with metabolic syndrome components. A cross-sectional study

Background and aims

Increased plasma phytosterols, which reflect enhanced cholesterol absorption, have been related to an increased risk of cardiovascular disease (CVD). However, high CVD risk conditions, such as obesity, diabetes and the metabolic syndrome (MetS) have been associated with reduced cholesterol absorption. We investigated associations between plasma noncholesterol sterols and MetS components.

Methods and results

With a cross-sectional design, we related MetS components to plasma noncholesterol sterol-to-cholesterol ratios measured by gas chromatography in 674 dyslipidemic patients and 361 healthy subjects participating in a prospective cohort study.Plasma phytosterol-to-cholesterol ratios were inversely associated with all components of the MetS. In the dyslipidemic group, multivariable analyses showed that a 1-SD increase in sitosterol-to-cholesterol ratio was associated with a reduced risk for any MetS feature, ranging from 0.57 (95% CI, 0.45 to 0.71) for visceral adiposity to 0.82 (95% CI, 0.69 to 0.98) for high blood pressure. The risk of having MetS was nearly halved, with ORs of 0.49 (95% CI, 0.38 to 0.64) or 0.56 (95% CI, 0.44-0.70), depending on the definition. Results were opposed for plasma lathosterol, a marker of cholesterol synthesis. Most findings were reproduced in the healthy cohort. ApoE genotype was unrelated to plasma noncholesterol sterols.

Conclusion

In both dyslipidemic and healthy populations, MetS is associated with increased plasma lathosterol, a cholesterol synthesis marker, and decreased plasma sitosterol, a marker of cholesterol absorption. Elevated plasma phytosterols related to a lower frequency of cardiometabolic risk factors, suggesting that they are associated with a reduced CVD risk.     

To eat or not to eat; regulation by the melanocortin system

The central melanocortin (MC) system is one of the best-characterized neuropeptidergic systems involved in the regulation of energy balance. This short review describes the role of the central MC system in feeding behavior. Pharmacological, anatomical and genetic studies show that activation of the MC system reduces meal size, whereas de-activation of the MC system increases meal size. Several brain regions, including distinct hypothalamic nuclei and the hindbrain, are involved in this process. Further dissection of MC pathways in feeding behavior is the subject of recent and probably future studies. As the MC system is involved in animal models of obesity and (possibly) anorexia, it appears that this is a target system for development of drugs for the treatment of disturbed human eating behavior.     

Association of Adiposity with Pulse Pressure Amongst Gujarati Indian Adolescents

Background and Aim:

The current study was conducted to determine the effect of adiposity on vascular distensibility in Gujarati Indian adolescents as research indicating the pathogenesis of hypertension among overweight and/or obese Indian adolescents is scant and ethnic differences exist in the pathogenesis of hypertension

Materials and Methods:

A cross-sectional study was conducted on 488 Gujarati Indian adolescents of 16-19 years age group. Adiposity was assessed in terms of BMI, Body Fat %, Fat Mass, Fat Mass Index and Waist Circumference. Arterial blood pressure was recorded and pulse pressure (PP) was calculated using the standard equation based on the difference between systolic blood pressure (SBP) and diastolic blood pressure (DBP). Pearson’s correlation coefficient was determined to find the association between the markers of adiposity and SBP, DBP and PP.

Result:

A significant positive correlationship was found between adiposity and PP in boys. However, no significant correlationship was found between adiposity and PP in girls.

Conclusion:

An increase in total as well as visceral adiposity is probably associated with a decrease in vascular distensibility in the Gujarati Indian adolescent boys but not in girls, thus indicating a protective role of female sex hormone estrogen which has been shown earlier to protect the vasculature from atherosclerosis, endothelial dysfunction which occurs with increase in adiposity.     

Interpersonal discrimination and markers of adiposity in longitudinal studies: a systematic review

While the impact of interpersonal discrimination on mental health is well established, its effects on physical health outcomes have not been fully elucidated. This study systematically reviewed the literature on the prospective association between interpersonal discrimination and markers of adiposity. Medline, Web of Science, Scopus, PsycInfo, SciELO, LILACS, Google Scholar, Capes/Brazil and ProQuest databases were used to retrieve relevant information in November 2016. The results from the 10 studies that met the inclusion criteria support an association between interpersonal self‐reported discrimination and the outcomes. In general, the most consistent findings were for weight and body mass index (BMI) among women, i.e. high levels of self‐reported discrimination were related to increased weight and BMI. Waist circumference (WC) showed a similar pattern of association with discrimination, in a positive direction, but an inverted U‐shaped association was also found. Despite a few inverse associations between discrimination and markers of adiposity, none of the associations were statistically significant. Overall, markers of adiposity were consistently associated with discrimination, mainly through direct and nonlinear associations. This review provides evidence that self‐reported discrimination can play an important role in weight, BMI and WC changes.     

Animal models of maternal high fat diet exposure and effects on metabolism in offspring: a meta‐regression analysis

Animal models of maternal high fat diet (HFD) demonstrate perturbed offspring metabolism although the effects differ markedly between models. We assessed studies investigating metabolic parameters in the offspring of HFD fed mothers to identify factors explaining these inter‐study differences. A total of 171 papers were identified, which provided data from 6047 offspring. Data were extracted regarding body weight, adiposity, glucose homeostasis and lipidaemia. Information regarding the macronutrient content of diet, species, time point of exposure and gestational weight gain were collected and utilized in meta‐regression models to explore predictive factors. Publication bias was assessed using Egger's regression test. Maternal HFD exposure did not affect offspring birthweight but increased weaning weight, final bodyweight, adiposity, triglyceridaemia, cholesterolaemia and insulinaemia in both female and male offspring. Hyperglycaemia was found in female offspring only. Meta‐regression analysis identified lactational HFD exposure as a key moderator. The fat content of the diet did not correlate with any outcomes. There was evidence of significant publication bias for all outcomes except birthweight. Maternal HFD exposure was associated with perturbed metabolism in offspring but between studies was not accounted for by dietary constituents, species, strain or maternal gestational weight gain. Specific weaknesses in experimental design predispose many of the results to bias.     

Feasibility of liver stiffness measurement in morbidly obese patients undergoing bariatric surgery using XL probe

Objective: Prevalence of non-alcoholic fatty liver disease is rising in the Western world and reaches up to 90% in patients undergoing bariatric surgery. Fibroscan^® as a non-invasive tool for liver stiffness measurement (LSM) has several limitations in morbidly obese patients. Only few data exist about the technical feasibility and accuracy of LSM in these patients. We aimed to analyse the feasibility of LSM by Fibroscan^® in bariatric patients.

Materials and methods: In morbidly obese patients, LSM was performed using XL probe. Measurements were termed reliable if 10 successful measurements with a success rate ≥60% and an interquartile range/median (IQR/M) <0.3 were obtained, unreliable if 10 successful measurements were obtained but the IQR/M was >0.3, and they were termed failed if they were neither reliable nor unreliable.

Results: A total of 149 patients were included (87 with liver biopsies); mean BMI was 51.6?±?8.5?kg/m². In 41% LSM using XL-probe was reliable, in 22% unreliable and in 37% failed. Failed LSM was significantly more frequent in patients with higher BMI compared to reliable and unreliable measurements (p?Conclusions: LSM with XL probe is feasible in almost two-thirds of morbidly obese patients with a BMI?≥50?kg/m². Reliable prediction of advanced fibrosis appears to be possible even if formal criteria of successful measurements are not met.     

Fitness but not weight status is associated with projected physical independence in older adults

Obesity and fitness have been associated with older adults’ physical independence. We aimed to investigate the independent and combined associations of physical fitness and adiposity, assessed by body mass index (BMI) and waist circumference (WC) with the projected ability for physical independence. A total of 3496 non-institutionalized older adults aged 65 and older (1167 male) were included in the analysis. BMI and WC were assessed and categorized according to established criteria. Physical fitness was evaluated with the Senior Fitness Test and individual test results were expressed as Z-scores. Projected ability for physical independence was assessed with the 12-item composite physical function scale. Logistic regression was used to estimate the odds ratio (OR) for being physically dependent. A total of 30.1 % of participants were classified as at risk for losing physical independence at age 90 years. Combined fitness and fatness analysis demonstrated that unfit older adults had increased odds ratio for being physically dependent in all BMI categories (normal: OR = 9.5, 95 %CI = 6.5–13.8; overweight: OR = 6.0, 95 %CI = 4.3–8.3; obese: OR = 6.7, 95 %CI = 4.6–10.0) and all WC categories (normal: OR = 10.4, 95%CI = 6.5–16.8; middle: OR = 6.2, 95 %CI = 4.1–9.3; upper: OR = 7.0, 95 %CI = 4.8–10.0) compared to fit participants that were of normal weight and fit participants with normal WC, respectively. No increased odds ratio was observed for fit participants that had increased BMI or WC. In conclusion, projected physical independence may be enhanced by a normal weight, a normal WC, or an increased physical fitness. Adiposity measures were not associated with physical independence, whereas fitness is independently related to physical independence. Independent of their weight and WC status, unfit older adults are at increased risk for losing physical independence.     

Physical activity growth curves relate to adiposity in adolescents

PurposeFindings from prospective studies on associations between physical activity and adiposity among youth are inconsistent. Our aim was to describe physical activity trajectories during secondary school and examine the association with change in adiposity in youth.MethodsPhysical activity was measured in 20 survey cycles from 1999 to 2005; anthropometrics were measured in survey cycles 1, 12, and 19. Individual growth curves modeling moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) were estimated. Estimates of initial level and rate of decline in MVPA and VPA bouts per week were included as potential predictors of body fat% and body mass index using age- and sex-specific linear regression.ResultsComplete data were available for 840 and 760 adolescents aged 12–13 years at baseline, followed from survey cycles 1–12 and 12–19, respectively. Among girls, yearly declines of one MVPA and one VPA bout per week during earlier adolescence were associated with increases of 0.19 (95% confidence interval [CI], 0.02–0.36) and 0.47 (95% CI, 0.015–0.92) units of body fat%, respectively. In boys, a yearly decline of one MVPA bout per week was associated with an increase of 0.38 (95% CI, 0.05–0.70) units of body fat% during later adolescence.ConclusionsObesity prevention programs should include strategies to prevent declines in physical activity.