Sex differences in obesity and the regulation of energy homeostasis

Twelve-month outcomes of a father-child lifestyle intervention delivered by trained local facilitators in underserved communities: The Healthy Dads Healthy Kids dissemination trial

Healthy Dads Healthy Kids (HDHK) was the first program internationally to specifically target overweight and obese fathers to improve their children's health. In previous randomized controlled trials, HDHK generated meaningful short-term improvements in the adiposity, physical activity, and eating behaviors of both fathers and children. The aim of this dissemination trial was to evaluate the 12-month impact of HDHK when delivered by trained facilitators across four low socioeconomic and regional communities in the Hunter Region, Australia. The study was a nonrandomized, prospective trial with minimal eligibility criteria (i.e., father body mass index [BMI] ≥ 25 kg/m2 and children aged 4-12 years). HDHK included eight weekly practical and theoretical sessions. Assessments were baseline, 3 months (post-intervention), 6-months, and 12-months. The primary outcome was fathers' weight. Secondary outcomes included child BMI z-score and validated lifestyle behavior measures (e.g., physical activity, diet). Overall, 189 fathers (mean age: 40.2 years, BMI: 32.6 kg/m2) and 306 children (mean age: 8.1 years) participated in one of 10 HDHK programs in four areas. Intention-to-treat linear mixed models revealed a significant mean reduction in fathers' weight at post-intervention (-3.6 kg, 95% confidence interval: -4.3, -2.9), which was maintained at 12 months (71% retention). Corresponding improvements were also detected in children's BMI z-score and a range of lifestyle behaviors for both fathers and children. Attendance and satisfaction levels were high. Positive intervention effects observed in previous randomized controlled trials were largely replicated and sustained for 12 months when HDHK was delivered by trained local facilitators in underserved communities. Further investigation into the key systems, processes, and contextual factors required to deliver HDHK at scale appears warranted.

CO2 anesthesia on Drosophila survival in aging research

Carbon dioxide (CO₂ ) exposure is a common method of anesthesia in studies of Drosophila melanogaster. A number of negative side effects of CO₂ anesthesia have been reported. It is not clear whether the length of CO₂ anesthesia time affects Drosophila survival in aging research. Here, we examined the potential effect of the CO₂ anesthesia time length of 10-150 min. We found that long CO₂ exposure could lead to Drosophila death, more significant in males. The longer the anesthesia time is, the longer it takes for flies to wake up. Long-time CO₂ anesthesia can reduce the lifespan. Our stress tests showed that long-time CO₂ anesthesia can increase the average survival time in both males and females under starvation conditions, but can only increase female lifespan under H₂ O₂ oxidative stress. Long-time CO₂ anesthesia also significantly affects physiological traits, with spontaneous activity increased in females but decreased in males, and reduced female fecundity. Our study suggests that limiting the CO₂ anesthesia time and giving enough recovery time before performing physiological tests are important in Drosophila aging research.

Sex-specific analysis of renal cell carcinoma histology and survival in Japan: A population-based study 2004 to 2016

Background and aims

In Western countries, sex differences in renal cell carcinoma (RCC) histology and survival have been previously described: compared with men, clear cell subtype is more common but overall prognosis is better among women. The goal of the present study was to examine sex differences in RCC histology and survival in Japan, using a large-scale population-based data set.

Methods

With the use of a population-based cancer registry in Japan (2004-2016), patients with primary RCC were followed for 5 years (median follow-up time 2.1 years). We distinguished histological subtypes of clear cell, papillary, and chromophobe from "others" subtype. Sex-specific prevalence ratio (PR) for each histological subtype was estimated by Poisson regression with robust variance, adjusted for age and year of diagnosis. Sex-specific survival rates were estimated by Cox proportional hazard regression, adjusted for age, year of diagnosis, histological subtypes, and other prognostic variables, with multiple imputation.

Results

The prevalence of clear cell and "others" subtypes was similar between men and women among all the 5265 study subjects during the 12 years of study (clear cell, male 88.6% vs female 87.1%; "others", male 5.3% vs female 5.3%). However, papillary subtype was less common among women than men (male 4.6% vs female 2.8%; PR = 0.63; 95% CI, 0.45-0.88), while chromophobe subtype was more common among women (male 1.6% vs female 4.8%; PR = 3.18; 95% CI, 2.26-4.47). Although "others" subtype (but not papillary/chromophobe subtypes) independently predicted prognosis (HR = 1.74; 95% CI, 1.32-2.30), no sex differences were observed in RCC survival.

Conclusion

We did not observe a statistically significant difference in the prevalence of clear cell subtype between men and women in Japan, which differs from the pattern previously described in Western countries. Sex differences in RCC histology may not affect RCC survival in this population.

Interaction Effect of Sex and Body Mass Index on Gray Matter Volume

Objective: Few studies have investigated sex differences in brain structure associated with body mass index (BMI), and the related findings are inconsistent. In this study, we aimed to investigate the effect of sex × BMI interactions on gray matter volume (GMV), and to determine the implications of any structural differences.

Methods: The final sample comprised 653 participants (449 women) who were assessed using voxel-based morphology analysis of T1-weighted magnetic resonance images. We used the voxel-based morphometry (VBM) to build a multiple regression model to explore the association between BMI and GMV, and used analysis of variance (ANOVA) to explore the BMI × sex interaction on GMV. A subset of 410 participants (291 women) underwent whole brain resting-state functional connectivity (rsFC) analysis to investigate sex differences in the seed (interaction) region. The cluster with a significant effect in the previous ANOVA analysis was used as a seed.

Results: A significant BMI × sex interaction was observed in the left anterior cingulate cortex (ACC), while GMV was negatively correlated with BMI in men but not in women. The rsFC between the left ACC and the caudate was lower in men than in women. Within the entire sample, the insula, caudate, and medial frontal cortex activities were negatively correlated with BMI while the cerebellum and postcentral gyrus activities were positively correlated with BMI.

Conclusions: Our findings address the interaction effect of BMI and sex on GM alterations. We found that the GMV in men seemed to be more likely to change with BMI than women, and the left ACC may be the reason for the increase in BMI of men, but not women.

Sex differences in the circadian misalignment effects on energy regulation

Shift work causes circadian misalignment and is a risk factor for obesity. While some characteristics of the human circadian system and energy metabolism differ between males and females, little is known about whether sex modulates circadian misalignment effects on energy homeostasis. Here we show-using a randomized cross-over design with two 8-d laboratory protocols in 14 young healthy adults (6 females)-that circadian misalignment has sex-specific influences on energy homeostasis independent of behavioral/environmental factors. First, circadian misalignment affected 24-h average levels of the satiety hormone leptin sex-dependently (P < 0.0001), with a ∼7% decrease in females (P < 0.05) and an ∼11% increase in males (P < 0.0001). Consistently, circadian misalignment also increased the hunger hormone ghrelin by ∼8% during wake periods in females (P < 0.05) without significant effect in males. Females reported reduced fullness, consistent with their appetite hormone changes. However, males reported a rise in cravings for energy-dense and savory foods not consistent with their homeostatic hormonal changes, suggesting involvement of hedonic appetite pathways in males. Moreover, there were significant sex-dependent effects of circadian misalignment on respiratory quotient (P < 0.01), with significantly reduced values (P < 0.01) in females when misaligned, and again no significant effects in males, without sex-dependent effects on energy expenditure. Changes in sleep, thermoregulation, behavioral activity, lipids, and catecholamine levels were also assessed. These findings demonstrate that sex modulates the effects of circadian misalignment on energy metabolism, indicating possible sex-specific mechanisms and countermeasures for obesity in male and female shift workers.

A qualitative research synthesis of contextual factors contributing to female overweight and obesity over the life course in sub-Saharan Africa

Objective

Adult women are disproportionately affected by overweight and obesity in Sub-Saharan African (SSA) countries. Existing evidence on the sociocultural context remains unconsolidated. In this qualitative research synthesis, we aggregate research literature on contextual factors that potentially predispose adult women and adolescent girls to overweight and obesity to inform research, policies and programs over the life course.

Methods

PubMed, CINAHL, PsychInfo, ProQuest Central, EMBASE, and Web of Science were searched to locate qualitative research articles conducted in SSA countries beginning in the year 2000. After assessment for eligibility and critical appraisal, 17 studies were included in the synthesis. Textual data and quotes were synthesized using meta-aggregation methods proposed by the Joanna Briggs Institute.

Results

The synthesized studies were conducted in South Africa, Ghana, Kenya and Botswana. The three overarching themes across these studies were body size and shape ideals, barriers to healthy eating, and barriers to physical activity, with cultural and social factors as cross-cutting influences within the major themes. Culturally, the supposedly ideal African woman was expected to be overweight or obese, and voluptuous, and this was associated with their identity. Although being overweight or obese was not acceptable to adolescent girls, they desired to be voluptuous. Healthy food choices among women and adolescent girls were hampered by several factors including affordability of nutritious foods and peer victimization. Both adult women and adolescent girls experienced ageism as a barrier to physical activity.

Significance

This is the first qualitative research synthesis to amplify the voices of women and girls in SSA countries highlighting the challenges they face in maintaining a healthy body weight. Sociocultural, institutional and peer-related factors were powerful forces shaping body size preferences, food choices and participation in physical activity. Our study findings provide insights for the design of contextually appropriate obesity prevention interventions and lay the foundation for further research studies.

Diabetes Type 2 and Kisspeptin: Central and Peripheral Sex-Specific Actions

Kisspeptin (KP) plays a major role in the regulation of reproduction governed by the hypothalamic-pituitary-gonadal (HPG) axis. However, recent findings suggest that the KP system is present not only centrally (at the level of the hypothalamus), but also in the peripheral organs crucial for the control of metabolism. The KP system is sexually differentiated in the hypothalamus, and it is of particular interest to study whether sex-specific responses to type 2 diabetes (DM2) exist centrally and peripherally. As collection of data is limited in humans, animal models of DM2 are useful to understand crosstalk between metabolism and reproduction. Sex-specific variations in the KP system reported in animals suggest a need for the development of gender specific therapeutic strategies to treat DM2.

Complementary Immunometabolic Effects of Exercise and PPARβ/δ Agonist in the Context of Diet-Induced Weight Loss in Obese Female Mice

Regular aerobic exercise, independently of weight loss, improves metabolic and anti-inflammatory states, and can be regarded as beneficial in counteracting obesity-induced low-grade inflammation. However, it is still unknown how exercise alters immunometabolism in a context of dietary changes. Agonists of the Peroxisome Proliferator Activated-Receptor beta/delta (PPARβ/δ) have been studied this last decade as "exercise-mimetics", which are potential therapies for metabolic diseases. In this study, we address the question of whether PPARβ/δ agonist treatment would improve the immunometabolic changes induced by exercise in diet-induced obese female mice, having switched from a high fat diet to a normal diet. 24 mice were assigned to groups according to an 8-week exercise training program and/or an 8-week treatment with 3 mg/kg/day of GW0742, a PPARβ/δ agonist. Our results show metabolic changes of peripheral lymphoid tissues with PPARβ/δ agonist (increase in fatty acid oxidation gene expression) or exercise (increase in AMPK activity) and a potentiating effect of the combination of both on the percentage of anti-inflammatory Foxp3+ T cells. Those effects are associated with a decreased visceral adipose tissue mass and skeletal muscle inflammation (TNF-α, Il-6, Il-1β mRNA level), an increase in skeletal muscle oxidative capacities (citrate synthase activity, endurance capacity), and insulin sensitivity. We conclude that a therapeutic approach targeting the PPARβ/δ pathway would improve obesity treatment.

Oral Monosodium Glutamate Differentially Affects Open-Field Behaviours, Behavioural Despair and Place Preference in Male and Female Mice

Background:

Monosodium glutamate (MSG) is a flavour enhancer which induces behavioural changes in animals. However the influence of sex on the behavioural response to MSG has not been investigated.

Objective:

The sex-differential effects of MSG on open-field behaviours, anxiety-related behaviour, behavioural despair, place-preference, and plasma/brain glutamate levels in adult mice were assessed.

Methods:

Mice were assigned to three groups (1-3), based on the models used to assess behaviours. Animals in group 1 were for the elevated-plus maze and tail-suspension paradigms, group 2 for the open-field and forced-swim paradigms, while mice in group 3 were for observation in the conditioned place preference paradigm. Mice in all groups were further assigned into five subgroups (10 males and 10 females), and administered vehicle (distilled water at 10 ml/kg) or one of four doses of MSG (20, 40, 80 and 160 mg/kg) daily for 6 weeks, following which they were exposed to the behavioural paradigms. At the end of the behavioural tests, the animals were sacrificed, and blood was taken for estimation of glutamate levels. The brains were also homogenised for estimation of glutamate levels.

Results:

MSG was associated with a reduction in locomotion in males and females (except at 160 mg/kg, male), an anxiolytic response in females, an anxiogenic response in males, and decreased behavioural despair in both sexes (females more responsive). Postconditioning MSG-associated place-preference was significantly higher in females. Plasma/ brain glutamate was not significantly different between sexes.

Conclusion:

Repeated MSG administration alters a range of behaviours in a sex-dependent manner in mice.

High body mass index, brain metabolism and connectivity: an unfavorable effect in elderly females

There are reported gender differences in brain connectivity associated with obesity. In the elderlies, the neural endophenotypes of obesity are yet to be elucidated. We aim at exploring the brain metabolic and connectivity correlates to different BMI levels in elderly individuals, taking into account gender as variable of interest.We evaluated the association between BMI, brain metabolism and connectivity, in elderly females and males, by retrospectively collecting a large cohort of healthy elderly subjects (N=222; age=74.03±5.88 [61.2-85.9] years; M/F=115/107; BMI=27.00±4.02 [19.21-38.79] kg/m2). Subjects underwent positron emission tomography with [18F]FDG. We found that, in females, high BMI was associated with increased brain metabolism in the orbitofrontal cortex (R=0.44; p<0.001). A significant BMI-by-gender interaction was present (F=7.024, p=0.009). We also revealed an altered connectivity seeding from these orbitofrontal regions, namely expressing as a decreased connectivity in crucial control/decision making circuits, and as an abnormally elevated connectivity in reward circuits, only in females. Our findings support a link between high BMI and altered brain metabolism and neural connectivity, only in elderly females. These findings indicate a strong gender effect of high BMI and obesity that brings to considerations for medical practice and health policy.

Epidemiology of Overweight and Obesity in Adults Living in Cameroon: A Systematic Review and Meta-Analysis

OBJECTIVE

This study aimed to summarize current data on overweight and obesity among adults living in Cameroon.

METHODS

PubMed, Embase, Web of Science, Global Index Medicus, African Journals Online, and local databases were searched for population-based cross-sectional studies conducted in the general population from January 2000 to December 2017. A random-effects model was used to pool data.

RESULTS

Overall, 26 studies (55,155 participants) were included. The prevalence of overweight was 26.0% (95% CI: 17.6%-35.3%) based on BMI. Furthermore, the overall prevalence of obesity was 15.1% (95% CI: 9.3%-22.1%) based on BMI, 16.4% (95% CI: 10.8%-22.8%) based on waist circumference ≥ 102 cm for males and ≥ 88 cm for females, 36.7% (95% CI: 26.8%-47.2%) based on waist circumference ≥ 94 cm for males and ≥ 80 cm for females, 32.6% (95% CI: 26.9%-38.7%) based on waist to hip ratio ≥ 0.90 for males and ≥ 0.85 for females, and 31.9% (95% CI: 27.8%-36.2%) based on percent body fat ≥ 25% for males and ≥ 35% for females. Overall, the burden was higher in females compared with males; there was no difference between urban and rural settings or between studies conducted in 2000 to 2009 and 2010 to 2016.

CONCLUSIONS

The burden of overweight and obesity is high among adults in Cameroon, putting many at increased risk for developing associated metabolic and cardiovascular complications.

Diet-induced obesity decreases rate-dependent depression in the Hoffmann's reflex in adult mice

Obesity is associated with balance and motor control deficits. We have recently shown that Group Ia muscle spindle afferents, the sensory arm of the muscle stretch reflex, are less responsive in mice fed a high-fat diet. Here we test the hypothesis that reflex excitability to sensory information from Group Ia muscle spindle afferents is altered in a mouse model of diet-induced obesity. We measured the anesthetized Hoffmann's or H-reflex, the electrical analog of the muscle stretch reflex. Adult mice of both sexes were fed a control diet (CD; 10% kcal from fat) or a high-fat diet (HFD; 60% kcal from fat) for 5, 10, or 15 weeks. We used three quantitative measures of H-reflex excitability: (1) H-reflex latency; (2) the percentage of motor neurons recruited from electrical stimulation of Group Ia muscle spindle afferents (Hmax /Mmax ); and (3) rate-dependent depression (RDD), the decrease in H-reflex amplitude to high frequency stimulation (20 stimuli at 5 Hz). A HFD did not significantly alter H latency (P = 0.16) or Hmax /Mmax ratios (P = 0.06), but RDD was significantly lower in HFD compared to CD groups (P < 0.001). Interestingly, HFD males exhibited decreased RDD compared to controls only after 5 and 10 weeks of feeding, but females showed progressive decreases in RDD that were only significant at 10 and 15 weeks on the HFD. These results suggest that high-fat feeding increases H-reflex excitability. Future studies are needed to determine whether these changes alter muscle stretch reflex strength and/or balance and to determine the underlying mechanism(s).

Estradiol and body weight during temporally targeted food restriction: Central pathways and peripheral metabolic factors

We used temporally-targeted food restriction (TTFR), in which ovariectomized rats had chow only for 2 h/day, to test the hypothesis that estradiol benzoate (EB) suppresses feeding and decreases body weight during brief (4 day) TTFR, as it does during ad libitum feeding. All rats lost weight during TTFR, but the loss was greater with EB treatment. However, OIL and EB-treated rats ate comparable amounts of chow during TTFR. We next investigated central nervous system pathways and peripheral hormonal and metabolic changes that accompany the effects of TTFR to determine the mechanism for this effect. Immunolabeling for fos in the nucleus of the solitary tract, the terminal site of vagal afferents from the gastrointestinal tract, was increased when rats on TTFR had access to chow for 1 h on the test day, indicating neuronal activation associated with consumption of the meal. However, fos immunolabeling was not affected by EB treatment, nor were numbers of the α subtype of estrogen receptors. TTFR had the expected effects on carbohydrate and lipid metabolites and metabolic hormones, with only slight differences in plasma glucose, triglycerides, and free fatty acids attributable to EB treatment. Interestingly, plasma corticosterone levels were greater in EB-treated rats on TTFR, and increased further after eating. Given that corticosterone affects metabolism, these findings suggest that elevated corticosterone may explain the persistence of EB-induced differences in body weight during TTFR despite the lack of effect on food intake.

An intersectional mixed methods approach to Native Hawaiian and Pacific Islander men's health

We used a convergent parallel design to explore NHPI men's multi-level perspectives of the factors that influence healthy eating, physical activity, and weight, to elicit recommendations for lifestyle interventions, and to understand the intersection of masculinity and health from a social constructionist perspective. From June to December 2017, NHPI men 18 years and older were recruited to participate in a survey and focus groups. The survey included demographic questions and questions about physical and cultural activities men engage in, perceived social support for lifestyle behaviors, dietary behaviors, masculine characteristics and values important to NHPI men. The Kessler Psychological Distress Scale was used to assess psychological distress. Focus groups were audio recorded and transcribed for a thematic analysis. Descriptive statistics were computed for survey data. We conducted eight focus groups with 89 NHPI men (50% Samoan, 20% Native Hawaiian, 30% Marshallese). The mean age of participants was 39 years, 43% reported some college or college graduate, 64% were currently married, and 63% were working full time. Ninety percent of men scored 20 or higher on the K10 scale indicating mild to severe psychological distress. Men described food as a major part of their culture and their identity. Men's roles were defined as provider and protector, with little attention is paid to their own health. Our study found that hegemonic, or traditional masculinity and social norms may encourage some men to put their health at risk but may also be used to motivate healthy behaviors.

Changes in insulin resistance mediate the associations between phthalate exposure and metabolic syndrome

BACKGROUND

Information on the relationships between phthalate exposure, insulin resistance, and metabolic syndrome (MetS) in younger adults is limited. It is still unclear whether changes in insulin resistance represent an intermediate biological mechanism linking phthalate exposure and MetS.

OBJECTIVE

To investigate the associations between cumulative risk of phthalates (such as daily intake [DI] and hazard index [HI]), insulin resistance, and MetS in younger adults and to examine the mediating role of insulin resistance in the associations between phthalate exposure and MetS.

METHODS

Urinary phthalate metabolite levels, insulin resistance (by using the Homeostatic Model Assessment of estimated Insulin Resistance [HOMA-IR]), and MetS status were determined in 435 military personnel in Taiwan. We estimated the DI of five phthalates: dimethyl phthalate (DMP), diethyl phthalate, dibutyl phthalate, benzyl butyl phthalate (BBzP), and di (2-ethylhexyl) phthalate and the HI based on urinary phthalate metabolite levels. Cross-sectional associations between DI and HI, HOMA-IR, and the indicators of MetS were explored using logistic regression models. Mediation analysis was conducted to assess the role of insulin resistance in the associations between phthalate exposure and MetS.

RESULTS

Higher DI_DMP was associated with an increased odds of high HOMA-IR and MetS (odds ratio [OR], 1.686; 95% confidence interval [CI], 1.079-2.634 for high HOMA-IR; OR, 2.329; 95% CI, 1.263-4.295 for MetS). The mediation analysis indicated that 43% of the association between higher DI_DMP and MetS was mediated by HOMA-IR. Higher DI_BBzP and HI were associated with an increased odds of abdominal obesity (OR, 1.816; 95% CI, 1.180-2.797 for the high DI_BBzP group; OR, 1.700, 95% CI, 1.105-2.614 for the high HI groups).

CONCLUSIONS

Exposure to environmental phthalates may be positively associated with insulin resistance and MetS. Insulin resistance may mediate these associations between exposure to certain phthalates and MetS.

Prevalence of Overweight and Obesity among European Preschool Children: A Systematic Review and Meta-Regression by Food Group Consumption

The aim of this review was to estimate the prevalence of overweight and obesity among European children aged 2–7 years from 2006 to 2016 and to analyze these estimations by gender, country, and food group consumption. We searched CINAHL, EMBASE, MEDLINE, and Web of Science databases from their inception until 27 February 2019 including cross-sectional studies and baseline measurements of cohort studies with overweight and obesity defined according to the International Obesity Task Force criteria. Both the inverse-variance fixed-effects method and the DerSimonian and Laird random effects method were used to determinate pooled prevalence estimates and their respective 95% confidence intervals (CIs). A total of 32 studies (n = 197,755 children) with data from 27 European countries were included. Overall, the pooled prevalence estimates of overweight/obesity in European children (aged 2–7 years) during the period 2006–2016 was 17.9% (95% CI: 15.8–20.0), and the pooled prevalence estimate of obesity was 5.3% (95% CI: 4.5–6.1). Southern European countries showed the highest prevalence of excess weight. Additional measures to address the obesity epidemic in early life should be established, especially in European countries where the prevalence of excess weight is very high.

Sex differences in metabolic effects of angiotensin-(1-7) treatment in obese mice

Background

Angiotensin-(1-7) is a beneficial hormone of the renin-angiotensin system known to play a positive role in regulation of blood pressure and glucose homeostasis. Previous studies have shown that in high-fat diet (HFD)-induced obese male mice, circulating angiotensin-(1-7) levels are reduced and chronic restoration of this hormone reverses diet-induced insulin resistance; however, this has yet to be examined in female mice. We hypothesized angiotensin-(1-7) would improve insulin sensitivity and glucose tolerance in obese female mice, to a similar extent as previously observed in male mice.

Methods

Five-week-old male and female C57BL/6J mice (8–12/group) were placed on control diet or HFD (16% or 59% kcal from fat, respectively) for 11 weeks. After 8 weeks of diet, mice were implanted with an osmotic pump for 3-week subcutaneous delivery of angiotensin-(1-7) (400 ng/kg/min) or saline vehicle. During the last week of treatment, body mass and composition were measured and intraperitoneal insulin and glucose tolerance tests were performed to assess insulin sensitivity and glucose tolerance, respectively. Mice were euthanized at the end of the study for blood and tissue collection.

Results

HFD increased body mass and adiposity in both sexes. Chronic angiotensin-(1-7) infusion significantly decreased body mass and adiposity and increased lean mass in obese mice of both sexes. While both sexes tended to develop mild hyperglycemia in response to HFD, female mice developed less marked hyperinsulinemia. There was no effect of angiotensin-(1-7) on fasting glucose or insulin levels among diet and sex groups. Male and female mice similarly developed insulin resistance and glucose intolerance in response to HFD feeding. Angiotensin-(1-7) improved insulin sensitivity in both sexes but corrected glucose intolerance only in obese female mice. There were no effects of sex or angiotensin-(1-7) treatment on any of the study outcomes in control diet-fed mice.

Conclusions

This study provides new evidence for sex differences in the impact of chronic angiotensin-(1-7) in obese mice, with females having greater changes in glucose tolerance with treatment. These findings improve understanding of sex differences in renin-angiotensin mechanisms in obesity and illustrate the potential for targeting angiotensin-(1-7) for treatment of this condition.

A Life History Approach to the Female Sexual Orientation Spectrum: Evolution, Development, Causal Mechanisms, and Health

Women's capacity for sexual fluidity is at least as interesting a phenomenon from the point of view of evolutionary biology and behavioral endocrinology as exclusively homosexual orientation. Evolutionary hypotheses for female nonheterosexuality have failed to fully account for the existence of these different categories of nonheterosexual women, while also overlooking broader data on the causal mechanisms, physiology, ontogeny, and phylogeny of female nonheterosexuality. We review the evolutionary-developmental origins of various phenotypes in the female sexual orientation spectrum using the synergistic approach of Tinbergen's four questions. We also present femme-specific and butch-specific hypotheses at proximate and ultimate levels of analysis. This review article indicates that various nonheterosexual female phenotypes emerge from and contribute to hormonally mediated fast life history strategies. Life history theory provides a biobehavioral explanatory framework for nonheterosexual women's masculinized body morphology, psychological dispositions, and their elevated likelihood of experiencing violence, substance use, obesity, teenage pregnancy, and lower general health. This pattern of life outcomes can create a feedback loop of environmental unpredictability and harshness which destabilizes intrauterine hormonal conditions in mothers, leading to a greater likelihood of fast life history strategies, global health problems, and nonheterosexual preferences in female offspring. We further explore the potential of female nonheterosexuality to function as an alloparental buffer that enables masculinizing alleles to execute their characteristic fast life history strategies as they appear in the female and the male phenotype. Synthesizing life history theory with the female sexual orientation spectrum enriches existing scientific knowledge on the evolutionary-developmental mechanisms of human sex differences.

Sex differences in the metabolic effects of the renin-angiotensin system

Obesity is a global epidemic that greatly increases risk for developing cardiovascular disease and type II diabetes. Sex differences in the obese phenotype are well established in experimental animal models and clinical populations. While having higher adiposity and obesity prevalence, females are generally protected from obesity-related metabolic and cardiovascular complications. This protection is, at least in part, attributed to sex differences in metabolic effects of hormonal mediators such as the renin-angiotensin system (RAS). Previous literature has predominantly focused on the vasoconstrictor arm of the RAS and shown that, in contrast to male rodent models of obesity and diabetes, females are protected from metabolic and cardiovascular derangements produced by angiotensinogen, renin, and angiotensin II. A vasodilator arm of the RAS has more recently emerged which includes angiotensin-(1-7), angiotensin-converting enzyme 2 (ACE2), mas receptors, and alamandine. While accumulating evidence suggests that activation of components of this counter-regulatory axis produces positive effects on glucose homeostasis, lipid metabolism, and energy balance in male animal models, female comparison studies and clinical data related to metabolic outcomes are lacking. This review will summarize current knowledge of sex differences in metabolic effects of the RAS, focusing on interactions with gonadal hormones and potential clinical implications.

The association of overall diet quality with BMI and waist circumference by education level in Mexican men and women

OBJECTIVE

The present study evaluated the association of two measures of diet quality with BMI and waist circumference (WC), overall and by education level, among Mexican men and women.

DESIGN

We constructed two a priori indices of diet quality, the Mexican Diet Quality Index (MxDQI) and the Mexican Alternate Healthy Eating Index (MxAHEI), which we examined relative to BMI and WC. We computed sex-specific multivariable linear regression models for the total sample and by education level.

SETTING

Mexico.

PARTICIPANTS

Mexican men (n 954) and women (n 1356) participating in the Mexican National Health and Nutrition Survey 2012.

RESULTS

Total dietary scores were not associated with BMI in men and women, but total MxDQI was inversely associated with WC in men (-0·10, 95 % CI -0·20, -0·004 cm). We also found that some results differed by education level in men. For men with the lowest education level, a one-unit increase in total MxDQI and MxAHEI score was associated with a mean reduction in BMI of 0·11 (95 % CI -0·18, 0·04) and 0·18 (95 % CI -0·25, -0·10) kg/m2, respectively. Likewise, a one-unit increase in total MxDQI and MxAHEI score was associated with a mean change in WC of -0·30 (95 % CI -0·49, -0·11) and -0·53 (95 % CI -0·75, -0·30) cm, respectively, in men with the lowest level of education. In women, the association of diet quality scores with BMI and WC was not different by education level.

CONCLUSIONS

Our findings suggest that a higher diet quality in men with low but not high education is associated with lower BMI and WC.

Association between dietary insulin index and load with obesity in adults

PURPOSE

Hyperinsulinemia is linked to the development of various chronic diseases, especially obesity given to the role of insulin responses in body fat accumulation; hence, the current study aimed to examine the association of insulinemic potential of the diet with general and abdominal obesity among a large population of Iranian adults.

METHODS

This cross-sectional study was carried out among 8691 adult participants aged 18-55 years. Dietary data were collected using a validated dish-based 106-item semi-quantitative food frequency questionnaire. Dietary insulin index (DII) was computed through considering food insulin index values published earlier. Dietary insulin load (DIL) was also calculated using a standard formula. Assessment of anthropometric measures was conducted through a self-administered questionnaire. General obesity was defined as body mass index ≥ 25 kg/m², and abdominal obesity as waist circumference ≥ 94 cm for men and ≥ 80 cm for women.

RESULTS

Mean age of study participants was 36.8 ± 8.1 years; 60.3% were women. Compared with the lowest quintile, women in the highest quintile of DIL were less likely to be abdominally obese (OR 0.73; 95% CI 0.57-0.92). Such significant association was not seen after controlling for potential confounders (OR 0.86; 95% CI 0.44-1.67). Neither in crude nor in adjusted models, we observed a significant association between DIL and general obesity among men and women. In terms of dietary insulin index, men in the top quintile of DII were more likely to be generally overweight or obese compared with those in the bottom quintile (OR 1.27; 95% CI 1.00-1.62). This association became non-significant after controlling for demographic characteristics (OR 1.14; 95% CI 0.84-1.56). Furthermore, in thefully adjusted model, women in the top quintile of DII were more likely to have general obesity compared with those in the bottom quintile (OR 1.40; 95% CI 1.07-1.84).

CONCLUSIONS

We found that adherence to a diet with a high DII was associated with greater odds of general obesity among women, but not in men. Although such information might help to draw conclusions on the practical relevance of the shown findings, further studies, specifically of prospective design, are warranted.

Gene-by-Sex Interactions in Mitochondrial Functions and Cardio-Metabolic Traits

We studied sex differences in over 50 cardio-metabolic traits in a panel of 100 diverse inbred strains of mice. The results clearly showed that the effects of sex on both clinical phenotypes and gene expression depend on the genetic background. In support of this, genetic loci associated with the traits frequently showed sex specificity. For example, Lyplal1, a gene implicated in human obesity, was shown to underlie a sex-specific locus for diet-induced obesity. Global gene expression analyses of tissues across the panel implicated adipose tissue "beiging" and mitochondrial functions in the sex differences. Isolated mitochondria showed gene-by-sex interactions in oxidative functions, such that some strains (C57BL/6J) showed similar function between sexes, whereas others (DBA/2J and A/J) showed increased function in females. Reduced adipose mitochondrial function in males as compared to females was associated with increased susceptibility to obesity and insulin resistance. Gonadectomy studies indicated that gonadal hormones acting in a tissue-specific manner were responsible in part for the sex differences.

A free-choice high-fat, high-sucrose diet induces hyperphagia, obesity, and cardiovascular dysfunction in female cycling and pregnant rats

The main objective of these studies was to characterize metabolic, body composition, and cardiovascular responses to a free-choice high-fat, high-sucrose diet in female cycling and pregnant rats. In the nonpregnant state, female Sprague-Dawley rats offered a 3-wk free-choice high-fat, high-sucrose diet had greater energy intake, adiposity, serum leptin, and triglyceride concentrations compared with rats fed with standard chow and developed glucose intolerance. In addition, choice-diet-fed rats had larger cardiac ventricular weights, smaller kidney and pancreas weights, and higher blood pressure than chow-fed rats, but they did not exhibit resistance artery endothelial dysfunction. When the free-choice diet continued throughout pregnancy, rats remained hyperphagic, hyperleptinemic, and obese. Choice pregnant rats exhibited uterine artery endothelial dysfunction and had smaller fetuses compared with chow pregnant rats. Pregnancy normalized mean arterial blood pressure and pancreas weights in choice rats. These studies are the first to provide a comprehensive evaluation of free-choice high-fat, high-sucrose diet on metabolic and cardiovascular functions in female rats, extending the previous studies in males to female cycling and pregnant rodents. Free-choice diet may provide a new model of preconceptual maternal obesity to study the role of increased energy intake, individual food components, and preexisting maternal obesity on maternal and offspring physiological responses during pregnancy and after birth.

Can professional football clubs deliver a weight management programme for women: a feasibility study

Background

Levels of obesity remain high in the UK. The Football Fans in Training (FFIT) randomised controlled trial (RCT) demonstrated that a 12-week, gender-sensitised weight management, physical activity and healthy eating group programme delivered through professional football clubs helped men aged 35–65 years with BMI at least 28 kg/m² lose a clinically-significant amount of weight. We aimed to test the feasibility of a minimally-adapted FFIT programme for delivery to women by assessing recruitment and completion rates; determining if the programme content and delivery required further refinement; and evaluating the potential of FFIT for Women to deliver improvements in weight and other clinical, behavioural and psychological outcomes.

Methods

A feasibility study of the FFIT for Women programme including before-and-after measurements of clinical (weight, waist, body mass index [BMI], blood pressure) behavioural (self-reported physical activity, food and alcohol intake) and psychological (self-esteem, positive and negative affect, physical and mental HRQoL) outcomes at five professional football clubs. Post-programme focus groups assessed acceptability of the programme format, content and style of delivery for women.

Results

Recruitment across the five clubs resulted in 123 women aged 35–65 years with BMI at least 28 kg/m² taking part in the study. The mean weight (95.3 kg) and BMI (36.6 kg/m2) of the cohort were both suggestive of high risk of future disease. Of 123 women who started the programme, 94 (76%) completed it; 72 (58.5%) returned for 12-week follow-up measurements. Participants compared FFIT for Women favourably to commercial weight loss programmes and emphasised the importance of the programme’s physical activity content. They also spoke positively about group dynamics, suggested that the approach to food was less restrictive than in other weight loss approaches, and broadly enjoyed the football setting. Mean weight loss was 2.87 kg (95% CI 2.09, 3.65, p ≤ 0.001). Mean waist reduction was 3.84 cm (2.92, 4.77, p ≤ 0.001).

Conclusion

In this evaluation, FFIT for Women was feasible, acceptable and demonstrated potential as a weight loss programme. Our findings suggest the programme has the potential to produce outcomes that are on a par with existing commercial and state-funded offerings.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-6255-2) contains supplementary material, which is available to authorized users.

Deletion of PHGDH in adipocytes improves glucose intolerance in diet-induced obese mice

Serine is a nonessential amino acid and plays an important role in cellular metabolism. In mammalian serine biosynthesis, 3-phosphoglycerate dehydrogenase (PHGDH) is considered a rate-limiting enzyme and is required for normal development. Although the biological functions of PHGHD in the nervous system have been intensively studied, its function in adipose tissue is unknown. In this study, we found that PHGDH is abundantly expressed in mature adipocytes of white adipose tissue. We generated an adipocyte-specific PHGDH knockout mouse (PHGDH FKO) and used it to investigate the role of serine biosynthesis in adipose tissues. Although PHGDH FKO mice had no apparent defects in adipose tissue development, these mice ameliorated glucose intolerance upon diet-induced obesity. Additionally, we found that the serine levels increase drastically in the adipose tissues of obese wild type mice, whereas no significant rise was observed in PHGDH FKO mice. Furthermore, wild type mice fed a serine-deficient diet also exhibited better glucose tolerance. These results suggest that PHGDH-mediated serine biosynthesis has important roles in adipose tissue glucose metabolism and could be a therapeutic target for diabetes in humans.

Association between dairy consumption, dietary calcium intake and general and abdominal obesity among Iranian adults

AIM

To assess the association of dairy consumption and dietary calcium intake with general and abdominal obesity in a large sample of Iranian adults.

METHODS

In this cross-sectional study, dairy consumption and dietary calcium intake were assessed using a validated dish-based 106-item semi-quantitative food frequency questionnaire in 6582 Iranian adults aged 18-55 years living in Isfahan. A self-administered validated questionnaire was used to collect data on anthropometric measures. Overweight or obesity was considered as body mass index ≥25 kg/m², and abdominal obesity as waist circumference ≥88 cm for women and ≥102 cm for men.

RESULTS

Mean age of study participants was 36.8 ± 8.1 years. Compared with the lowest quartile, men in the highest quartile of dietary calcium intake had greater odds for general obesity (OR: 1.29, 95% CI: 1.03-1.60). This relationship was significant even after adjustment for age and energy intake (OR: 1.28, 95% CI: 1.03-1.60). However, such relationship was not seen in women. No other significant associations were observed between dairy and dietary calcium intake with general or abdominal obesity.

CONCLUSION

Dietary calcium intake was positively associated with general obesity in men, but not in women. No significant association was seen between dairy consumption and general or central adiposity.

Effects of Estrogens on Central Nervous System Neurotransmission: Implications for Sex Differences in Mental Disorders

Nearly one of every five US individuals aged 12 years old or older lives with certain types of mental disorders. Men are more likely to use various types of substances, while women tend to be more susceptible to mood disorders, addiction, and eating disorders, all of which are risks associated with suicidal attempts. Fundamental sex differences exist in multiple aspects of the functions and activities of neurotransmitter-mediated neural circuits in the central nervous system (CNS). Dysregulation of these neural circuits leads to various types of mental disorders. The potential mechanisms of sex differences in the CNS neural circuitry regulating mood, reward, and motivation are only beginning to be understood, although they have been largely attributed to the effects of sex hormones on CNS neurotransmission pathways. Understanding this topic is important for developing prevention and treatment of mental disorders that should be tailored differently for men and women. Studies using animal models have provided important insights into pathogenesis, mechanisms, and new therapeutic approaches of human diseases, but some concerns remain to be addressed. The purpose of this chapter is to integrate human and animal studies involving the effects of the sex hormones, estrogens, on CNS neurotransmission, reward processing, and associated mental disorders. We provide an overview of existing evidence for the physiological, behavioral, cellular, and molecular actions of estrogens in the context of controlling neurotransmission in the CNS circuits regulating mood, reward, and motivation and discuss related pathology that leads to mental disorders.

Intermittent, extended access to preferred food leads to escalated food reinforcement and cyclic whole-body metabolism in rats: Sex differences and individual vulnerability

Compulsive binge eating is a hallmark of binge eating disorder and bulimia nervosa and is implicated in some obesity cases. Eating disorders are sexually dimorphic, with females more often affected than males. Animal models of binge-like eating based on intermittent access to palatable food exist; but, little is known regarding sex differences or individual vulnerability in these models with respect to the reinforcing efficacy of food, the development of compulsive- and binge-like eating, or associated changes in whole-body metabolism or body composition. Adolescent male (n = 24) and female (n = 32) Wistar rats were maintained on chow or a preferred, high-sucrose, chocolate-flavored diet in continuous or intermittent, extended access conditions. Body weight and composition, intake, fixed- and progressive-ratio operant self-administration, and whole body energy expenditure and respiratory exchange ratios were measured across an 11-week study period. Subgroup analyses were conducted to differentiate compulsive-like "high responder" intermittent access rats that escalated to extreme progressive-ratio self-administration performance vs. more resistant "low responders." Female rats had greater reinforcing efficacy of food than males in all diet conditions and were more often classified as "high responders". In both sexes, rats with intermittent access showed cycling of fuel substrate utilization and whole-body energy expenditure. Further, "high-responding" intermittent access female rats had especially elevated respiratory exchange ratios, indicating a fat-sparing phenotype. Future studies are needed to better understand the molecular and neurobiological basis of the sex and individual differences we have observed in rats and their translational impact for humans with compulsive, binge eating disorders.

The Association of Obesity and Cardiometabolic Traits With Incident HFpEF and HFrEF

OBJECTIVES

This study evaluated the associations of obesity and cardiometabolic traits with incident heart failure with preserved versus reduced ejection fraction (HFpEF vs. HFrEF). Given known sex differences in HF subtype, we examined men and women separately.

BACKGROUND

Recent studies suggest that obesity confers greater risk of HFpEF versus HFrEF. Contributions of associated metabolic traits to HFpEF are less clear.

METHODS

We studied 22,681 participants from 4 community-based cohorts followed for incident HFpEF versus HFrEF (ejection fraction ≥50% vs. <50%). We evaluated the association of body mass index (BMI) and cardiometabolic traits with incident HF subtype using Cox models.

RESULTS

The mean age was 60 ± 13 years, and 53% were women. Over a median follow-up of 12 years, 628 developed incident HFpEF and 835 HFrEF. Greater BMI portended higher risk of HFpEF compared with HFrEF (hazard ratio [HR]: 1.34 per 1-SD increase in BMI; 95% confidence interval [CI]: 1.24 to 1.45 vs. HR: 1.18; 95% CI: 1.10 to 1.27). Similarly, insulin resistance (homeostatic model assessment of insulin resistance) was associated with HFpEF (HR: 1.20 per 1-SD; 95% CI: 1.05 to 1.37), but not HFrEF (HR: 0.99; 95% CI: 0.88 to 1.11; p < 0.05 for difference HFpEF vs. HFrEF). We found that the differential association of BMI with HFpEF versus HFrEF was more pronounced among women (p for difference HFpEF vs. HFrEF = 0.01) when compared with men (p = 0.34).

CONCLUSIONS

Obesity and related cardiometabolic traits including insulin resistance are more strongly associated with risk of future HFpEF versus HFrEF. The differential risk of HFpEF with obesity seems particularly pronounced among women and may underlie sex differences in HF subtypes.

The physical and mental health burden of obesity in U.S. veterans: Results from the National Health and Resilience in Veterans Study

In this study, we provide an updated estimate of the prevalence of obesity in U.S. military veterans, and evaluate a broad range of sociodemographic, military, physical and mental health, and lifestyle characteristics associated with obesity in this population. Data were analyzed from a nationally representative sample of 3122 U.S. veterans who participated in the National Health and Resilience in Veterans Study (NHRVS). Associations between obesity status, and physical and mental health, and lifestyle variables were evaluated using multivariate logistic regression and linear regression analyses. Results revealed that 32.7% of U.S. veterans are obese, which is higher than the previously reported estimates for U.S. military veterans nationally, and was particularly high among younger and non-white veterans and those using the Veterans Heath Administration (VHA) healthcare system. Obesity was associated with greater trauma burden; elevated rates of a broad range of health conditions such as diabetes, arthritis, and heart disease, PTSD, nicotine dependence; poor physical and mental functioning and quality of life, and decreased engagement in an active lifestyle. Taken together, these results suggest that the prevalence of obesity is high in U.S. veterans and associated with substantial health burden. Results have implications for informing obesity prevention and treatment programs in veterans, and underscore the importance of assessing, monitoring, and treating obesity in this population.

Effects of exercise intervention on visceral fat in obese children and adolescents

INTRODUCTION

This meta-analysis study was aimed to assess the effects of exercise intervention on visceral fat in obese children and adolescents.

EVIDENCE ACQUISITION

Electronic database searches were performed in Academic Search Complete, CINAHL, Healthsource, MEDLINE, and SportDiscus, and from the earliest record to November 2017. Keywords included "exercise or training," "visceral fat," and "child or adolescent or youth." The inclusion criteria for eligible studies were as follows: 1) subjects were obese at baseline; 2) aged 6-19 years; 3) visceral fat was reported at baseline and after an intervention; and 4) studies were published in peer-reviewed journals written in English.

EVIDENCE SYNTHESIS

A total of 207 studies were observed at the initial search and 73 effect sizes (ESs) were derived from the 34 selected studies. The overall exercise intervention effect was large (Cohen's d [ES]=-1.003, 95% CI=-1.114, -0.892). Moderator analyses results showed that gender (Qb=8.23, df=2, P=0.016), exercise type (Qb=10.68, df=2, P=0.005), and intervention length (Qb=24.71, df=2, P<0.001) influenced the overall ES.

CONCLUSIONS

The group of both boys and girls (ES=-0.95) who participated combined exercise program (Aerobic + Resistance training; ES=-1.17) for 12 months (ES=-1.24) appeared to be the most effective exercise strategy for reducing visceral fat in obese youth.

Long-term weight loss following a randomised controlled trial of a weight management programme for men delivered through professional football clubs: the Football Fans in Training follow-up study

Background

Rising levels of obesity require interventions that support people in long-term weight loss. The Football Fans in Training (FFIT) programme uses loyalty to football teams to engage men in weight loss. In 2011/12, a randomised controlled trial (RCT) found that the FFIT programme was effective in helping men lose weight up to 12 months.

Objectives

To investigate the long-term weight, and other physical, behavioural and psychological outcomes up to 3.5 years after the start of the RCT; the predictors, mediators and men’s qualitative experiences of long-term weight loss; cost-effectiveness; and the potential for long-term follow-up via men’s medical records.

Design

A mixed-methods, longitudinal cohort study.

Setting

Thirteen professional Scottish football clubs from the RCT and 16 additional Scottish football clubs that delivered the FFIT programme in 2015/16.

Participants

A total of 665 men who were aged 35–65 years at the RCT baseline measures and who consented to follow-up after the RCT (intervention group, n = 316; comparison group, n = 349), and 511 men who took part in the 2015/16 deliveries of the FFIT programme.

Interventions

None as part of this study.

Main outcome measures

Objectively measured weight change from the RCT baseline to 3.5 years.

Results

In total, 488 out of 665 men (73.4%) attended 3.5-year measurements. Participants in the FFIT follow-up intervention group sustained a mean weight loss from baseline of 2.90 kg [95% confidence interval (CI) 1.78 to 4.02 kg; p < 0.001], and 32.2% (75/233) weighed ≥ 5% less than at baseline. Participants in the FFIT follow-up comparison group (who participated in routine deliveries of the FFIT programme after the RCT) lost a mean of 2.71 kg (95% CI 1.65 to 3.77 kg; p < 0.001), and 31.8% (81/255) achieved ≥ 5% weight loss. Both groups showed long-term improvements in body mass index, waist circumference, percentage body fat, blood pressure, self-reported physical activity (PA) (including walking), the consumption of fatty and sugary foods, fruit and vegetables and alcohol, portion sizes, self-esteem, positive and negative affect, and physical and mental health-related quality of life (HRQoL). Mediators included self-reported PA (including walking) and sitting time, the consumption of fatty and sugary foods and fruit and vegetables, portion sizes, self-esteem, positive affect, physical HRQoL, self-monitoring of weight, autonomous regulation, internal locus of control, perceived competence, and relatedness to other FFIT programme participants and family members. In qualitative interviews, men described continuing to self-monitor weight and PA. Many felt that PA was important for weight control, and walking remained popular; most were still aware of portion sizes and tried to eat fewer snacks. The FFIT programme was associated with an incremental cost-effectiveness of £10,700–15,300 per quality-adjusted life-year (QALY) gained at 3.5 years, and around £2000 per QALY gained in the lifetime analysis. Medical record linkage provided rich information about the clinical health outcomes of the FFIT RCT participants, and 90% of men (459/511) who took part in the 2015/16 FFIT programme gave permission for future linkage.

Conclusions

Participation in the FFIT programme under both research (during the FFIT RCT) and routine (after the FFIT RCT) delivery conditions led to significant long-term weight loss. Further research should investigate (1) how to design programmes to improve long-term weight loss maintenance, (2) longer-term follow-up of FFIT RCT participants and (3) very long-term follow-up via medical record linkage.

Trial registration

Current Controlled Trials ISRCTN32677491.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 6, No. 9. See the NIHR Journals Library website for further project information. The Scottish Executive Health Department Chief Scientist Office (CSO) funded the feasibility pilot that preceded the FFIT RCT (CZG/2/504). The Medical Research Council (MRC) funded Kate Hunt and additional developmental research through the MRC/CSO Social and Public Health Sciences Unit Gender and Health programme (5TK50/25605200-68094).

Deformable torso phantoms of Chinese adults for personalized anatomy modelling

In recent years, there has been increasing demand for personalized anatomy modelling for medical and industrial applications, such as ergonomics device development, clinical radiological exposure simulation, biomechanics analysis, and 3D animation character design. In this study, we constructed deformable torso phantoms that can be deformed to match the personal anatomy of Chinese male and female adults. The phantoms were created based on a training set of 79 trunk computed tomography (CT) images (41 males and 38 females) from normal Chinese subjects. Major torso organs were segmented from the CT images, and the statistical shape model (SSM) approach was used to learn the inter-subject anatomical variations. To match the personal anatomy, the phantoms were registered to individual body surface scans or medical images using the active shape model method. The constructed SSM demonstrated anatomical variations in body height, fat quantity, respiratory status, organ geometry, male muscle size, and female breast size. The masses of the deformed phantom organs were consistent with Chinese population organ mass ranges. To validate the performance of personal anatomy modelling, the phantoms were registered to the body surface scan and CT images. The registration accuracy measured from 22 test CT images showed a median Dice coefficient over 0.85, a median volume recovery coefficient (RCvlm ) between 0.85 and 1.1, and a median averaged surface distance (ASD) < 1.5 mm. We hope these phantoms can serve as computational tools for personalized anatomy modelling for the research community.

Dietary sources of cumulative phthalates exposure among the U.S. general population in NHANES 2005-2014

BACKGROUND

Anti-androgenic phthalates are reproductive toxicants that may have additive effects on male development. Diet is the primary exposure source for most phthalates, which contaminate the food supply through food contact materials and industrialized production.

OBJECTIVE

To compare dietary sources of cumulative phthalates exposure between "food at home" (e.g. food consumed from a grocery store) and "food away from home" (e.g. food consumed from fast food/restaurants and cafeterias) in the U.S. general population.

METHODS

We estimated cumulative phthalates exposure by calculating daily intake from metabolite concentrations in urinary spot samples for 10,253 participants (≥6 years old) using National Health and Nutrition Examination Survey (NHANES, 2005-2014) data. We constructed a biologically relevant metric of phthalates daily intake (∑androgen-disruptor, μg/kg/day) by converting phthalates into anti-androgen equivalent terms prior to their summation. Particular foods and the percent of total energy intake (TEI) consumed from multiple dining out sources were ascertained from 24-h recall surveys. Associations with ∑androgen-disruptor levels were estimated for children, adolescents, and adults using multivariable linear regression.

RESULTS

We observed a consistent positive association between dining out and Σandrogen-disruptor levels across the study population (p-trend <0.0001). Among adolescents, high consumers of foods outside the home had 55% (95% CI: 35%, 78%) higher Σandrogen-disruptor levels compared to those who only consumed food at home. The contribution of specific dining out sources to Σandrogen-disruptor levels varied by age group. For example, cafeteria food was associated with 15% (95% CI: 4.0%, 28%) and 64% (95% CI: 40%, 92%) higher Σandrogen-disruptor levels in children and adults, respectively. Particular foods, especially sandwiches (i.e. cheeseburgers), were associated with increased Σandrogen-disruptor levels only if they were purchased away from home (p < 0.01).

CONCLUSION

Dining out may be an important source of biologically relevant cumulative phthalates exposure among the U.S.

POPULATION

Future studies should evaluate modifiable production practices that remove phthalates from the food supply in addition to the efficacy of interventions that promote eating fresh foods prepared at home.

Prevalence of general and abdominal obesity in Portugal: comprehensive results from the National Food, nutrition and physical activity survey 2015-2016

BACKGROUND

This study includes, for the first time, estimates of general and abdominal obesity prevalence for all ages of the Portuguese population, using common standardized methodologies. Results are compared by sex, age groups, educational level and geographical regions.

METHODS

Participants were a representative sample of the Portuguese population aged between 3 months and 84 years of age (n = 6553), enrolled in the National Food, Nutrition and Physical Activity Survey, 2015-2016. Objective anthropometric measurements included length/height, weight and body circumferences, performed according to standard procedures. Body mass index (BMI) was classified according to the World Health Organization (WHO) growth charts for children and adolescents, and WHO criteria for adults. Abdominal obesity was defined in adults as waist-hip ratio ≥ 0.85 in women or ≥ 0.90 in men. Prevalence estimates and 95% confidence intervals (95%CI) were weighted according to a complex sampling design, considering stratification by seven geographical regions and cluster effect for the selected Primary Health Care Unit.

RESULTS

The national prevalence of obesity is 22.3% (95%CI: 20.5-24.0), significantly higher in women. Obesity prevalence is much higher in the elderly (39.2%, 95%CI. 34.2-44.2), while children and adolescents have the lowest prevalence around 8-9%. In a regression model, three knot points denoting an inflection of obesity prevalence across the life span were observed around 5, 15 and 75 years. The prevalence of pre-obesity at national level is 34.8% (95%CI: 32.9-36.7), higher in men, and almost 18% of children and 24% of adolescents have pre-obesity. The sex- and age-standardized prevalence of obesity ranged from 38.3% (95%CI: 34.6-42.1) to 13.1% (95%CI: 10.3-15.9) for the less and the most educated individuals, respectively. Although some geographical region disparities, obesity prevalence did not significantly differed across regions (p = 0.094). The national prevalence of abdominal obesity in adults is 50.5% (95%CI: 47.9-53.1), particularly high in the elderly (80.2%).

CONCLUSION

Almost 60% of the general Portuguese population is obese or pre-obese. Women, elderly and less educated individuals present the highest obesity prevalence. Abdominal obesity, in particular, seems to be a relevant public health problem among the elderly men.

Bile acid detoxifying enzymes limit susceptibility to liver fibrosis in female SHRSP5/Dmcr rats fed with a high-fat-cholesterol diet

During middle age, women are less susceptible to nonalcoholic steatohepatitis (NASH) than men. Thus, we investigated the underlying molecular mechanisms behind these sexual differences using an established rat model of NASH. Mature female and male stroke-prone spontaneously hypertensive 5/Dmcr rats were fed control or high-fat-cholesterol (HFC) diets for 2, 8, and 14 weeks. Although HFC-induced hepatic fibrosis was markedly less severe in females than in males, only minor gender differences were observed in expression levels of cytochrome P450 enzymes (CYP)7A1, CYP8B1 CYP27A1, and CYP7B1, and multidrug resistance-associated protein 3, and bile salt export pump, which are involved in fibrosis-related bile acid (BA) kinetics. However, the BA detoxification-related enzymes UDP-glucuronosyltransferase (UGT) and sulfotransferase (SULT) 2A1, and the nuclear receptors constitutive androstane receptor (CAR) and pregnane X receptor (PXR), were strongly suppressed in HFC-fed males, and were only slightly changed in HFC-diet fed females. Expression levels of the farnesoid X receptor and its small heterodimer partner were similarly regulated in a gender-dependent fashion following HFC feeding. Hence, the pronounced female resistance to HFC-induced liver damage likely reflects sustained expression of the nuclear receptors CAR and PXR and the BA detoxification enzymes UGT and SULT.

The relationship of waist circumference and body mass index to grey matter volume in community dwelling adults with mild obesity

Objective

Previous work has shown that high body mass index (BMI) is associated with low grey matter volume. However, evidence on the relationship between waist circumference (WC) and brain volume is relatively scarce. Moreover, the influence of mild obesity (as indexed by WC and BMI) on brain volume remains unclear. This study explored the relationships between WC and BMI and grey matter volume in a large sample of Japanese adults.

Methods

The participants were 792 community-dwelling adults (523 men and 269 women). Brain magnetic resonance images were collected, and the correlation between WC or BMI and global grey matter volume were analysed. The relationships between WC or BMI and regional grey matter volume were also investigated using voxel-based morphometry.

Results

Global grey matter volume was not correlated with WC or BMI. Voxel-based morphometry analysis revealed significant negative correlations between both WC and BMI and regional grey matter volume. The areas correlated with each index were more widespread in men than in women. In women, the total area of the regions significantly correlated with WC was slightly greater than that of the regions significantly correlated with BMI.

Conclusions

Results show that both WC and BMI were inversely related to regional grey matter volume, even in Japanese adults with somewhat mild obesity. Especially in populations with less obesity, such as the female participants in current study, WC may be more sensitive than BMI as a marker of grey matter volume differences associated with obesity.

Greater Reward-Related Neuronal Response to Hedonic Foods in Women Compared with Men

OBJECTIVE

The current study aimed to identify how sex influences neurobiological responses to food cues, particularly those related to hedonic eating, and how this relates to obesity propensity, using functional magnetic resonance imaging (fMRI).

METHODS

Adult men and women who were either obesity resistant (OR) or obesity prone (OP) underwent fMRI while viewing visual food cues (hedonic foods, neutral foods, and nonfood objects) in both fasted and fed states.

RESULTS

When fasted, a significant sex effect on the response to hedonic vs. neutral foods was observed, with greater responses in women than men in the nucleus accumbens (P = 0.0002) and insula (P = 0.010). Sex-based differences were not observed in the fed state. No significant group effects (OP vs. OR) or group-by-sex interactions were observed in fasted or fed states.

CONCLUSIONS

Greater fasted responses to hedonic food cues in reward-related brain regions were observed in women compared with men, suggesting that women may be more sensitive to the reward value of hedonic foods than men when fasted. This may indicate sex-dependent neurophysiology underlying eating behaviors.

Effect of a Gender-Tailored eHealth Weight Loss Program on the Depressive Symptoms of Overweight and Obese Men: Pre-Post Study

BACKGROUND

Obesity and depression are of two of the largest contributors to the global burden of disease in men. Although lifestyle behavior change programs can improve participants' weight and depressive symptoms, the evidence is limited by a lack of male participants and a reliance on face-to-face treatment approaches, which are not accessible or appealing for many men.

OBJECTIVE

This study examined the effect of a gender-tailored electronic health (eHealth) program on the depressive symptoms of a community sample of overweight and obese men with or without depression. A secondary aim was to determine whether the eHealth, self-directed format of the program was a feasible and acceptable treatment approach for the subgroup of men with depression at baseline.

METHODS

In total, 209 overweight/obese men from the Hunter Region of Australia were assessed before and after completing a self-administered eHealth weight loss program over 3 months. To increase engagement, most program elements were socio-culturally targeted to appeal specifically to men and included printed materials, a DVD, motivational text messages, online- or app-based self-monitoring, and other weight loss tools (eg, pedometer). Depressive symptoms were measured with the validated 8-item Patient Health Questionnaire (PHQ-8). Program feasibility and acceptability were assessed with a process questionnaire plus recruitment and retention rates. Changes in depressive symptoms and weight were examined using intention-to-treat linear mixed models, adjusted for the centered baseline score and other covariates. Effect sizes were estimated with Cohen's d.

RESULTS

At baseline, the mean weight and age of the sample was 105.7 kg (standard deviation [SD] 14.0) and 46.6 years (SD 11.3), respectively. Overall, 36 men (36/209, 17.2%) were experiencing depression (PHQ-8 score ≥10). Retention rates were comparable between men with and without depression (32/36, 88.9% vs 145/173, 83.8%; P=.44). At posttest, depressive symptoms had reduced by 1.8 units (95% CI 1.3 to 2.3; P<.001; d=0.5) for the whole sample. These improvements were particularly notable in the subgroup of men with depression (-5.5 units; P<.001; d=1.0) and 72.2% (26/36) of this subgroup no longer met the criterion for depression at posttest. A corresponding, albeit smaller, intervention effect on depressive symptoms was also observed in men without depression (-1.0 units; P<.001; d=0.4). The overall intervention effect on weight was -4.7 kg (d=1.3), which did not vary significantly by depression status. Program acceptability, feasibility, and online engagement metrics were also comparable between men with and without depression.

CONCLUSIONS

A gender-tailored eHealth lifestyle program generated short-term improvements in the mental health of overweight and obese men, particularly for men with depression at baseline. Despite receiving no personalized support, men with depression reported high levels of satisfaction and engagement with the program. As such, a longer-term controlled trial testing an adapted version of the program for this subgroup is warranted.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12612000749808; https://www.anzctr.org.au/ Trial/Registration/TrialReview.aspx?id=362575 (Archived by WebCite at http://www.webcitation.org/6wJvbRsNW).

Impact of Pregnancy on Weight Loss and Quality of Life Following Gastric Banding

BACKGROUND-OBJECTIVES

Despite pregnancy being a common event following laparoscopic adjustable gastric banding (LAGB), there is little comprehensive data regarding its effect on postoperative outcome. The aim of this study was to assess the impact of pregnancy on the postoperative changes in quality of life (QOL) and total weight loss 3 years after LAGB.

SETTING

Multi-institutional, France.

METHODS

This is a study of the subgroup of 561 women of childbearing age included in a 3-year prospective multicenter trial assessing the results of patients undergoing LAGB surgery. Data from the 61 women who got pregnant and delivered during the follow-up period were compared with the 270 who did not.

RESULTS

Pregnant women achieved lower final weight loss compared to the non-pregnant group [final body mass index (BMI) 35.4 vs. 31.1 kg/m(2), p < 0.0001; excess weight loss (%EBL) 43.6 vs. 64.7 %, p < 0.0001]. Longitudinal assessment demonstrated pregnancy as a significant and independent factor of poor weight loss (p < 0.0001). The timing of conception after LAGB (between the first 18 months or after) had no significant impact on weight loss changes. There was no significant difference in short form-36 health survey (SF-36) QOL scores between both groups.

CONCLUSIONS

Pregnancy following gastric banding affects negatively postoperative final weight loss, even if occurring 18 months postoperatively, but has no effect on QOL improvement.

Socio-demographic and behavioural determinants of body mass index among an adult population in rural Northern Ghana: the AWI-Gen study

BACKGROUND

Obesity and associated cardiometabolic diseases are increasing in urban sub-Saharan Africa due to a complex epidemiological and nutritional transition. Related data on rural communities is scarce.

OBJECTIVES

The study characterized the socio-demographic and behavioural factors influencing body mass index (BMI) among adults in rural Northern Ghana Methods: A population-based cross-sectional study involving adults aged 40-60 years residing in the Kassena-Nankana districts was undertaken. Demographic, socio-economic and behavioural data were collected along with measures of anthropometry. We determined factors associated with BMI among women and men.

RESULTS

A total of 2014 adults were studied. The median age was 51 (IQR 45-57) years and 54% were women. The prevalence of overweight/obesity was higher among women than men (18.4% vs. 7.2%; p < 0.001), whilst underweight was more prevalent in men (18.3% vs. 13.1%; p = 0.001). Participants with the highest level of education and a high household socio-economic status had higher BMIs than those in the lowest strata in both men (β = 0.074, p = 0.028 and β = 0.072, p < 0.001, respectively) and women (β = 0.174, p = 0.001 and β = 0.109, p < 0.001, respectively). Men (β = -0.050; p < 0.001) and women (β = -0.073; p < 0.001) of the Nankana ethnic group had a lower BMI than the Kassena ethnic group. Among men, alcohol consumption (β = -0.021; p = 0.001) and smoking (β = -0.216; p < 0.001) were associated with lower BMI. Smokeless tobacco was associated with lower BMI among women. Pesticide exposure was associated with higher BMI (β = 0.022; p = 0.022) among men.

CONCLUSION

Age, sex, ethno-linguistic group and prevailing socio-demographic and behavioural factors within this rural community in Northern Ghana influence BMI. The observed positive association between pesticide use and BMI warrants further investigation.

Sex and Gender Differences in Prevention of Type 2 Diabetes

Lifestyle intervention programs are effective in the prevention of type 2 diabetes mellitus (T2DM) in high risk populations. However, most studies only give limited information about the influence of sex and/or gender effectiveness of these interventions. So far, similar outcome was reported for diabetes progression and weight loss. Nevertheless, long-term data on cardiovascular outcome are sparse but favoring women regarding all-cause and cardiovascular mortality. In both men and women, sex hormone imbalances and reproductive disorders are associated with a higher risk of T2DM development. Diabetes prevention approaches are reported for polycystic ovary syndrome, gestational diabetes mellitus, and erectile dysfunction and are presented in this review. In the surgical treatment options for morbid obese patients, sex and gender differences are present. Choices and preferences of adherence to lifestyle and pharmacological interventions, expectations, treatment effects, and complications are influenced by sex or gender. In general, bariatric surgery is performed more often in women seeking medical/surgical help to lose weight. Men are older and have higher comorbidities and mortality rates and worse follow-up outcome after bariatric surgery. A more gender-sensitive clinical approach, as well as consideration of ethnicity may improve quality of life and increase health and life expectancy in men and women with a high risk for subsequent progression to T2DM.

Sexually dimorphic effects of dietary sugar on lifespan, feeding and starvation resistance in Drosophila

Lifespan and health in older age are strongly influenced by diet. Feeding Drosophila melanogaster diets high in sugar has increasingly been used as an experimental model to understand the physiological effects of unhealthy, contemporary human diets. Several metabolic parameters and physiological responses to nutrition are known to be dependent on the sex of the animal. However, sexual dimorphism in the responses to high-sugar diets in fruit flies has not been examined. Here we show that a high-sugar diet in Drosophila melanogaster elicits sexually dimorphic effects on feeding behaviour, starvation resistance and lifespan. Females feed less on such diets, while males feed more, and these feeding responses may have secondary consequences. Females, more than males, gain the ability to resist periods of starvation from high-sugar diets, indicating that the female response to excess sugar may be geared towards surviving food shortages in early life. At the same time, female lifespan is more susceptible to the detrimental effects of high sugar diets. Our study reveals differences between Drosophila sexes in their responses to sugar-rich diets, indicating the fruit fly could be used as a model to understand the sexually dimorphic features of human metabolic health.

Strategies to increase the efficacy of using gut microbiota for the modulation of obesity

Obesity is one of the most serious global public health challenges of the 21st century. The adjustment of gut microbiota is often recommended as an efficient strategy to treat obesity. This modulation of gut microbiota can be performed by many methods, including dietary intervention, antibiotic application, the use of prebiotics and probiotics, bariatric surgery and faecal microbiota transplantation. In most cases, positive effects have been observed in response to treatment, but invalid and even contrary effects have also been observed in some cases due to factors that are unrelated to intervention methods, such as genetic factors, patient age or gender, environmental microbiota, climate, geography and lifestyle. These factors can cause variation of gut microbial populations and thus should also be taken into consideration when selecting modulation strategies.

The sex of specific neurons controls female body growth in Drosophila

Sexual dimorphisms in body size are widespread throughout the animal kingdom but their underlying mechanisms are not well characterized. Most models for how sex chromosome genes specify size dimorphism have emphasized the importance of gonadal hormones and cell-autonomous influences in mammals versus strictly cell-autonomous mechanisms in Drosophila melanogaster. Here, we use tissue-specific genetics to investigate how sexual size dimorphism (SSD) is established in Drosophila. We find that the larger body size characteristic of Drosophila females is established very early in larval development via an increase in the growth rate per unit of body mass. We demonstrate that the female sex determination gene, Sex-lethal (Sxl), functions in central nervous system (CNS) neurons as part of a relay that specifies the early sex-specific growth trajectories of larval but not imaginal tissues. Neuronal Sxl acts additively in 2 neuronal subpopulations, one of which corresponds to 7 median neurosecretory cells: the insulin-producing cells (IPCs). Surprisingly, however, male-female differences in the production of insulin-like peptides (Ilps) from the IPCs do not appear to be involved in establishing SSD in early larvae, although they may play a later role. These findings support a relay model in which Sxl in neurons and Sxl in local tissues act together to specify the female-specific growth of the larval body. They also reveal that, even though the sex determination pathways in Drosophila and mammals are different, they both modulate body growth via a combination of tissue-autonomous and nonautonomous inputs.

The prevalence of food addiction in a large sample of adolescents and its association with addictive substances

The prevalence of overweight and obesity is increasing, due to, among other factors, increased availability of highly palatable food (food high in fat, salt and/or sugar). It has been proposed that certain foods and/or eating behaviours may be addictive, to a degree comparable to substances of abuse. The Yale Food Addiction Scale (YFAS) measures 'food addiction' by translating the diagnostic criteria for substance use disorder to eating behaviour. So far, only a few studies have examined the prevalence of food addiction in children with the YFAS for children (YFAS-C). Large-scale studies, especially among adolescents, are lacking. Adolescence is of particular interest because it is a period wherein unhealthy eating behaviours or addictive tendencies are likely to develop. The current study examines the prevalence of food addiction using the YFAS-C in a large group of Dutch adolescents (N = 2653) aged 14-21 years. With Generalized Estimation Equation (GEE) analysis we tested the relationship between food addiction symptoms and smoking, cannabis use, alcohol use, and sugar intake through drinks, while controlling for gender, age, educational level and weight class. In the total sample 2.6% met the criteria for a food addiction 'diagnosis', and the average symptom count was 1.0 (SD = 1.3, range 0-7). Symptoms of food addiction were positively associated with smoking, alcohol use, cannabis use and sugar intake. We propose that future studies focus on possible genetic/(neuro)biological mechanisms involved in both food addiction and substance use and that longitudinal designs are needed to examine possible causal pathways.

Detecting the genetic link between Alzheimer's disease and obesity using bioinformatics analysis of GWAS data

Alzheimer's disease (AD) represents the major form of dementia in the elderly. In recent years, accumulating evidence indicate that obesity may act as a risk factor for AD, while the genetic link between the two conditions remains unclear. This bioinformatics analysis aimed to detect the genetic link between AD and obesity on single nucleotide polymorphisms (SNPs), gene, and pathway levels based on genome-wide association studies data. A total of 31 SNPs were found to be shared by AD and obesity, which were linked to 7 genes. These genes included PSMC3, CELF1, MYBPC3, SPI1, APOE, MTCH2 and RAPSN. Further functional enrichment analysis of these genes revealed the following biological pathways, including proteasome, osteoclast differentiation, hypertrophic cardiomyopathy, dilated cardiomyopathy, Epstein-Barr virus and TLV-I infection, as well as several cancer associated pathways, to be common among AD and obesity. The findings deepened our understanding on the genetic basis linking obesity and AD and may help shape possible prevention and treatment strategies.

Obesity Accelerates Alzheimer-Related Pathology in APOE4 but not APOE3 Mice

Alzheimer's disease (AD) risk is modified by both genetic and environmental risk factors, which are believed to interact to cooperatively modify pathogenesis. Although numerous genetic and environmental risk factors for AD have been identified, relatively little is known about potential gene-environment interactions in regulating disease risk. The strongest genetic risk factor for late-onset AD is the ε4 allele of apolipoprotein E (APOE4). An important modifiable risk factor for AD is obesity, which has been shown to increase AD risk in humans and accelerate development of AD-related pathology in rodent models. Potential interactions between APOE4 and obesity are suggested by the literature but have not been thoroughly investigated. In the current study, we evaluated this relationship by studying the effects of diet-induced obesity (DIO) in the EFAD mouse model, which combines familial AD transgenes with human APOE3 or APOE4. Male E3FAD and E4FAD mice were maintained for 12 weeks on either a control diet or a Western diet high in saturated fat and sugars. We observed that metabolic outcomes of DIO were similar in E3FAD and E4FAD mice. Importantly, our data showed a significant interaction between diet and APOE genotype on AD-related outcomes in which Western diet was associated with robust increases in amyloid deposits, β-amyloid burden, and glial activation in E4FAD but not in E3FAD mice. These findings demonstrate an important gene-environment interaction in an AD mouse model that suggests that AD risk associated with obesity is strongly influenced by APOE genotype.