Could Vaping be a New Weapon in the Battle of the Bulge?

IMPLICATIONS: Obesity is set to overtake tobacco smoking in many countries as the primary cause of several high-cost diseases. Tobacco smoking mitigates weight gain through nicotine's effect on the brain and metabolism. Smoking, however, is associated with many illnesses and premature death and appropriately has been discouraged leading to declining prevalence rates. This article explores the emerging perception that vaping electronic cigarettes with nicotine and flavors could deliver similar appetite and weight control effects as smoking. The potential to reduce risks associated with excess weight deserves exploration. An initial research agenda is suggested.

Multi-omic integrated networks connect DNA methylation and miRNA with skeletal muscle plasticity to chronic exercise in Type 2 diabetic obesity.

Epigenomic regulation of the transcriptome by DNA methylation and posttranscriptional gene silencing by miRNAs are potential environmental modulators of skeletal muscle plasticity to chronic exercise in healthy and diseased populations. We utilized transcriptome networks to connect exercise-induced differential methylation and miRNA with functional skeletal muscle plasticity. Biopsies of the vastus lateralis were collected from middle-aged Polynesian men and women with morbid obesity (44 kg/m(2) ± 10) and Type 2 diabetes before and following 16 wk of resistance (n = 9) or endurance training (n = 8). Longitudinal transcriptome, methylome, and microRNA (miRNA) responses were obtained via microarray, filtered by novel effect-size based false discovery rate probe selection preceding bioinformatic interrogation. Metabolic and microvascular transcriptome topology dominated the network landscape following endurance exercise. Lipid and glucose metabolism modules were connected to: microRNA (miR)-29a; promoter region hypomethylation of nuclear receptor factor (NRF1) and fatty acid transporter (SLC27A4), and hypermethylation of fatty acid synthase, and to exon hypomethylation of 6-phosphofructo-2-kinase and Ser/Thr protein kinase. Directional change in the endurance networks was validated by lower intramyocellular lipid, increased capillarity, GLUT4, hexokinase, and mitochondrial enzyme activity and proteome. Resistance training also lowered lipid and increased enzyme activity and caused GLUT4 promoter hypomethylation; however, training was inconsequential to GLUT4, capillarity, and metabolic transcriptome. miR-195 connected to negative regulation of vascular development. To conclude, integrated molecular network modelling revealed differential DNA methylation and miRNA expression changes occur in skeletal muscle in response to chronic exercise training that are most pronounced with endurance training and topographically associated with functional metabolic and microvascular plasticity relevant to diabetes rehabilitation.

The fecal microbiotas of women of Pacific and New Zealand European ethnicities are characterized by distinctive enterotypes that reflect dietary intakes and fecal water content.

Obesity is a complex, multifactorial condition that is an important risk factor for noncommunicable diseases including cardiovascular disease and type 2 diabetes. While prevention and management require a healthy and energy balanced diet and adequate physical activity, the taxonomic composition and functional attributes of the colonic microbiota may have a supplementary role in the development of obesity. The taxonomic composition and metabolic capacity of the fecal microbiota of 286 women, resident in Auckland New Zealand, was determined by metagenomic analysis. Associations with BMI (obese, nonobese), body fat composition, and ethnicity (Pacific, n = 125; NZ European women [NZE], n = 161) were assessed using regression analyses. The fecal microbiotas were characterized by the presence of three distinctive enterotypes, with enterotype 1 represented in both Pacific and NZE women (39 and 61%, respectively), enterotype 2 mainly in Pacific women (84 and 16%) and enterotype 3 mainly in NZE women (13 and 87%). Enterotype 1 was characterized mainly by the relative abundances of butyrate producing species, Eubacterium rectale and Faecalibacterium prausnitzii, enterotype 2 by the relative abundances of lactic acid producing species, Bifidobacterium adolescentis, Bifidobacterium bifidum, and Lactobacillus ruminis, and enterotype 3 by the relative abundances of Subdoligranulum sp., Akkermansia muciniphila, Ruminococcus bromii, and Methanobrevibacter smithii. Enterotypes were also associated with BMI, visceral fat %, and blood cholesterol. Habitual food group intake was estimated using a 5 day nonconsecutive estimated food record and a 30 day, 220 item semi-quantitative Food Frequency Questionnaire. Higher intake of 'egg' and 'dairy' products was associated with enterotype 3, whereas 'non-starchy vegetables', 'nuts and seeds' and 'plant-based fats' were positively associated with enterotype 1. In contrast, these same food groups were inversely associated with enterotype 2. Fecal water content, as a proxy for stool consistency/colonic transit time, was associated with microbiota taxonomic composition and gene pools reflective of particular bacterial biochemical pathways. The fecal microbiotas of women of Pacific and New Zealand European ethnicities are characterized by distinctive enterotypes, most likely due to differential dietary intake and fecal consistency/colonic transit time. These parameters need to be considered in future analyses of human fecal microbiotas.

Replacing Sedentary Time with Physically Active Behaviour Predicts Improved Body Composition and Metabolic Health Outcomes.

BACKGROUND: Discretionary leisure time for health-promoting physical activity (PA) is limited. This study aimed to predict body composition and metabolic health marker changes from PA reallocation using isotemporal substitution analysis. METHODS: Healthy New Zealand women (n = 175; 16-45 y) with high BMI (≥25 kg/m2) and high body fat percentage (≥30%) were divided into three groups by ethnicity (Maori n = 37, Pacific n = 54, and New Zealand European n = 84). PA, fat mass, lean mass, and metabolic health were assessed. Isotemporal substitution paradigms reallocated 30 min/day of sedentary behaviour to varying PA intensities. RESULTS: Reallocating sedentary behaviour with moderate intensity, PA predicted Maori women would have improved body fat% (14.83%), android fat% (10.74%), and insulin levels (55.27%) while the model predicted Pacific women would have improved waist-to-hip (6.40%) and android-to-gynoid (19.48%) ratios. Replacing sedentary time with moderate-vigorous PA predicted Maori women to have improved BMI (15.33%), waist circumference (9.98%), body fat% (16.16%), android fat% (12.54%), gynoid fat% (10.04%), insulin (55.58%), and leptin (43.86%) levels; for Pacific women, improvement of waist-to-hip-ratio (5.30%) was predicted. CONCLUSIONS: Sedentary behaviour must be substituted with PA of at least moderate intensity to reap benefits. Maori women received the greatest benefits when reallocating PA. PA recommendations to improve health should reflect the needs and current activity levels of specific populations.

Loss of the pregnancy-induced rise in cortisol concentrations in the ewe impairs the fetal insulin-like growth factor axis.

Maternal cortisol levels increase during pregnancy. Although this change is important for optimal fetal growth, the mechanisms of the changes in growth remain unclear. The hypothesis examined was that alterations in maternal plasma cortisol concentrations are associated with changes in the fetal insulin-like growth factor (IGF) axis. Pregnant ewes in late gestation (115 ± 0.4 days) were studied: six control animals, five ewes given 1 mg kg(-1) day(-1) cortisol (high cortisol) and five adrenalectomised ewes given 0.5-0.6 mg kg(-1) day(-1) cortisol (low cortisol). Blood samples were taken throughout the experiment and at necropsy (130 ± 0.2 days) and fetal liver was frozen for mRNA analysis. Fetal IGF-I and insulin plasma concentrations were lower and insulin-like growth factor-binding protein-1 (IGFBP-1) concentrations were higher in the low cortisol group compared with those in the control group (P < 0.05). Fetal liver IGF-II and IGFBP-3 mRNA were decreased in low cortisol animals compared with controls (P < 0.05). There were no significant changes in these parameters in the high cortisol group, and there were no changes in fetal liver IGF-I, growth hormone receptor, IGF-I receptor, IGF-II receptor, IGFBP-1 or IGFBP-2 mRNA levels between the groups. These data suggest that reduced fetal IGF availability contributes to reduced fetal growth when maternal cortisol secretion is impaired, but not during exposure to moderate increases in cortisol.

Objectively Measured Physical Activity Is Associated With Body Composition and Metabolic Profiles of Pacific and New Zealand European Women With Different Metabolic Disease Risks.

Objective: To assess associations between physical activity (PA), body composition, and biomarkers of metabolic health in Pacific and New Zealand European (NZE) women who are known to have different metabolic disease risks. Methods: Pacific (n = 142) or NZE (n = 162) women aged 18-45 years with a self-reported body mass index (BMI) of either 18.5-25.0 kg⋅m-2 or ≥30.0 kg⋅m-2 were recruited and subsequently stratified as either low (<35%) or high (≥35%) BF%, with approximately half of each group in either category. Seven-day accelerometery was used to assess PA levels. Fasting blood was analysed for biomarkers of metabolic health, and whole body dual-energy X-ray absorptiometry (DXA) was used to estimate body composition. Results: Mean moderate-to-vigorous physical activity (MVPA; min⋅day-1) levels differed between BF% (p < 0.05) and ethnic (p < 0.05) groups: Pacific high- 19.1 (SD 15.2) and low-BF% 26.3 (SD 15.6) and NZE high- 30.5 (SD 19.1) and low-BF% 39.1 (SD 18.4). On average Pacific women in the low-BF% group engaged in significantly less total PA when compared to NZE women in the low-BF% group (133 cpm); no ethnic difference in mean total PA (cpm) between high-BF% groups were observed: Pacific high- 607 (SD 185) and low-BF% 598 (SD 168) and NZE high- 674 (SD 210) and low-BF% 731 (SD 179). Multiple linear regression analysis controlling for age and deprivation showed a significant inverse association between increasing total PA and fasting plasma insulin among Pacific women; every 100 cpm increase in total PA was associated with a 6% lower fasting plasma insulin; no significant association was observed in NZE women. For both Pacific and NZE women, there was an 8% reduction in fasting plasma insulin for every 10-min increase in MVPA (p ≤ 0.05). Conclusion: Increases in total PA and MVPA are associated with lower fasting plasma insulin, thus indicating a reduction in metabolic disease risk. Importantly, compared to NZE, the impact of increased total PA on fasting insulin may be greater in Pacific women. Considering Pacific women are a high metabolic disease risk population, these pre-clinical responses to PA may be important in this population; indicating promotion of PA in Pacific women should remain a priority.

Outcomes of a culturally informed weight-loss competition for New Zealand Indigenous and Pacific peoples: a quasi-experimental trial.

BACKGROUND: Reducing obesity prevalence among marginalised subgroups with disproportionately high obesity rates is challenging. Given the promise of incentives and group-based programmes we trialled a culturally tailored, team-based weight-loss competition with New Zealand Maori (Indigenous) and Pacific Island people. METHODS: A quasi-experimental 12-months trial was designed. The intervention consisted of three six-months competitions, each with seven teams of seven members. Eligible participants were aged 16 years and older, with a BMI ≥30 kg/m2 and being at risk of or already diagnosed with type-2 diabetes or cardiovascular disease. Height, weight and waist circumference were measured at baseline, 6 and 12 months. RESULTS: Recruitment of a control group (n = 29) versus the intervention (n = 132) was poor and retention rates were low (52 and 27% of intervention participants were followed-up at six and 12 months, respectively). Thus, analysis of the primary outcome of individual percentage weight loss was restricted to the 6-months follow-up data. Although not significant, the intervention group appeared to lose more weight than the control group, in both the intention to treat and complete-case analyses. CONCLUSIONS: The intervention promoted some behaviour change in eating behaviours, and a resulting trend toward a reduction in waist circumference. TRIAL REGISTRATION: ACTRN12617000871347 Registered 15/6/2017 Retrospectively registered.

Moderate daily exercise activates metabolic flexibility to prevent prenatally induced obesity.

Obesity and its associated comorbidities are of major worldwide concern. It is now recognized that there are a number of metabolically distinct pathways of obesity development. The present paper investigates the effect of moderate daily exercise on the underlying mechanisms of one such pathway to obesity, through interrogation of metabolic flexibility. Pregnant Wistar rats were either fed chow ad libitum or undernourished throughout pregnancy, generating control or intrauterine growth restricted (IUGR) offspring, respectively. At 250 d of age, dual-emission x-ray absorptiometry scans and plasma analyses showed that moderate daily exercise, in the form of a measured amount of wheel running (56 m/d), prevented the development of obesity consistently observed in nonexercised IUGR offspring. Increased plasma C-peptide and hepatic atypical protein kinase Czeta levels explained increased glucose uptake and increased hepatic glycogen storage in IUGR offspring. Importantly, whereas circulating levels of retinol binding protein 4 were elevated in obese, nonexercised IUGR offspring, indicative of glucose sparing without exercise, retinol binding protein 4 levels were normalized in the exercised IUGR group. These data suggest that IUGR offspring have increased flexibility of energy storage and use and that moderate daily exercise prevents obesity development through activation of distinct pathways of energy use. Thus, despite a predisposition to develop obesity under sedentary conditions, obesity development was prevented in IUGR offspring when exercise was available. These results emphasize the importance of tailored lifestyle changes that activate distinct pathways of metabolic flexibility for obesity prevention.

Prenatally undernourished rats show increased preference for wheel running v. lever pressing for food in a choice task.

Maternal nutrition during pregnancy has a significant influence in establishing patterns of metabolism and postnatal behaviours in offspring, and therefore shapes their risk of developing disorders in later life. Although it is well established that a mismatch between food consumption and energy expenditure leads to obesity and metabolic dysregulation, little research has investigated the biological origin of such behaviour. We conducted the present experiments to investigate effects of early-life nutrition on preference between wheel running and lever pressing for food during adult life. To address this issue we employed a well-established experimental approach in the rat which has shown that offspring of mothers undernourished during pregnancy develop obesity and metabolic disorders when kept under standard laboratory conditions. Using this experimental approach, two studies were conducted where offspring of ad libitum-fed dams and dams undernourished throughout pregnancy were given the choice between wheel running and pressing a response lever for food. Across subsequent conditions, the rate at which the response lever provided food was varied from 0.22 to 6.0 (study 1) and 0.19 to 3.0 (study 2) pellets per min. Compared with the control group, offspring from dams undernourished during pregnancy showed a consistently greater preference for running over lever pressing for food throughout both experiments of the study. The results of the present study provide experimental evidence that a mother's nutrition during pregnancy can result in a long-term shift in her offspring's lifestyle choices that are relevant to obesity prevention. Such a shift, if endorsed, will have substantial and wide-ranging health consequences throughout the lifespan.

Adherence to daily dietary and activity goals set within a Maori and Pacific weight loss competition.

BACKGROUND: New Zealand Pacific and Maori populations measure disproportionately high on the international body mass index (BMI). Information is needed on what behavioural weight loss goals to recommend and how to attract and retain them in interventions. Our team weight loss competition trial for participants with a BMI ≥30 used cash prizes to incentivise completion of nine daily behaviour goals. This paper evaluates the theoretical merit of and adherence to these goals. METHODS: A qualitative component evaluation methodology was used. Trial data on team activity, demographics and anthropometric outcome data were extracted to determine frequency of daily goal completion by teams throughout the competition and to describe participant characteristics. T-tests were used to compare completion rates of the challenges, challenge completion by day of week and between weekdays and weekends. To examine adherence to the daily challenge activity over 24 weeks the total amount of completed challenges adjusted for number of active teams was plotted by week. A Body Shape Index (ABSI) was used to determine individual anthropometric change from baseline to 8, 16 and 24 weeks. Program documents were analysed to identify barriers to adherence and retention of participants. RESULTS: Of 19 teams (N = 130) who began only five teams performed daily goals across the whole 24 weeks. Adherence was highest during the first 8 weeks. No difference in performance between goals was found suggesting they were equally viable, though tasks worth less points were performed more frequently. Goal completion was higher on weekdays. The behaviour goals appeared to have theoretical merit in that more members of high performing teams experienced a positive change in their ABSI. CONCLUSIONS: Incentives offer a promising strategy for encouraging retention in weight loss interventions. This study suggests that participants in a competition will perform incentivised tasks. The findings however, are limited by missing data and high drop out of individuals and whole teams. Further research is needed on how to increase retention.

Dietary Patterns in New Zealand Women: Evaluating Differences in Body Composition and Metabolic Biomarkers.

The combinations of food consumed together (dietary patterns) may have a greater influence on health than nutrients or food groups consumed independently. This study investigated the relationship between dietary patterns, body composition and metabolic biomarkers of premenopausal New Zealand women from three ethnic groups. In total, 408 New Zealand European, Maori and Pacific women aged 16-45 years participated in the Women's EXPLORE (EXamining Predictors Linking Obesity Related Elements) study. Participants completed a 220-item food frequency questionnaire. Several body composition parameters and metabolic biomarkers were measured. Dietary patterns were extracted by principal component analysis and dietary pattern scores were categorised into tertiles to assess links with other measured parameters. Women with higher scores for the 'refined and processed' pattern were younger, had higher body mass index, total body fat, plasma leptin and plasma insulin (p < 0.001), and lower plasma ghrelin levels (p < 0.05) than women with lower scores. In addition, more Maori (51%) and Pacific (68%) women followed the 'refined and processed' pattern, while more New Zealand European women (40%) followed the 'sweet and savoury snacking' pattern. These data show that dietary pattern analysis is a useful tool to assess links between diet and metabolic health. It further reveals interesting ethnic group-specific differences in dietary pattern use.

Predictors Linking Obesity and the Gut Microbiome (the PROMISE Study): Protocol and Recruitment Strategy for a Cross-Sectional Study on Pathways That Affect the Gut Microbiome and Its Impact on Obesity.

BACKGROUND: The prevalence of obesity has increased substantially over recent decades and is associated with considerable health inequalities. Although the causes of obesity are complex, key drivers include overconsumption of highly palatable, energy-dense, and nutrient-poor foods, which have a profound impact on the composition and function of the gut microbiome. Alterations to the microbiome may play a critical role in obesity by affecting energy extraction from food and subsequent energy metabolism and fat storage. OBJECTIVE: We report the study protocol and recruitment strategy of the PRedictors linking Obesity and the gut MIcrobiomE (PROMISE) study, which characterizes the gut microbiome in 2 populations with different metabolic disease risk (Pacific and European women) and different body fat profiles (normal and obese). It investigates (1) the role of gut microbiome composition and functionality in obesity and (2) the interactions between dietary intake; eating behavior; sweet, fat, and bitter taste perception; and sleep and physical activity; and their impact on the gut microbiome, metabolic and endocrine regulation, and body fat profiles. METHODS: Healthy Pacific and New Zealand (NZ) European women aged between 18 and 45 years from the Auckland region were recruited for this cross-sectional study. Participants were recruited such that half in each group had either a normal weight (body mass index [BMI] 18.5-24.9 kg/m2) or were obese (BMI ≥30.0 kg/m2). In addition to anthropometric measurements and assessment of the body fat content using dual-energy x-ray absorptiometry, participants completed sweet, fat, and bitter taste perception tests; food records; and sleep diaries; and they wore accelerometers to assess physical activity and sleep. Fasting blood samples were analyzed for metabolic and endocrine biomarkers and DNA extracted from fecal samples was analyzed by shotgun sequencing. Participants completed questionnaires on dietary intake, eating behavior, sleep, and physical activity. Data were analyzed using descriptive and multivariate regression methods to assess the associations between dietary intake, taste perception, sleep, physical activity, gut microbiome complexity and functionality, and host metabolic and body fat profiles. RESULTS: Of the initial 351 women enrolled, 142 Pacific women and 162 NZ European women completed the study protocol. A partnership with a Pacific primary health and social services provider facilitated the recruitment of Pacific women, involving direct contact methods and networking within the Pacific communities. NZ European women were primarily recruited through Web-based methods and special interest Facebook pages. CONCLUSIONS: This cross-sectional study will provide a wealth of data enabling the identification of distinct roles for diet, taste perception, sleep, and physical activity in women with different body fat profiles in modifying the gut microbiome and its impact on obesity and metabolic health. It will advance our understanding of the etiology of obesity and guide future intervention studies involving specific dietary approaches and microbiota-based therapies. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12618000432213; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370874. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/14529.

The effect of neonatal leptin treatment on postnatal weight gain in male rats is dependent on maternal nutritional status during pregnancy.

An adverse prenatal environment may induce long-term metabolic consequences, in particular obesity, hyperleptinemia, insulin resistance, and type 2 diabetes. Although the mechanisms are unclear, this "programming" has generally been considered an irreversible change in developmental trajectory. Adult offspring of rats subjected to undernutrition (UN) during pregnancy develop obesity, hyperinsulinemia, and hyperleptinemia, especially in the presence of a high-fat diet. Using this model of maternal UN, we have recently shown that neonatal leptin treatment in females reverses the postnatal sequelae induced by developmental programming. To examine possible gender-related effects of neonatal leptin treatment, the present study investigated the effect of neonatal leptin treatment on the metabolic phenotype of adult male offspring. Leptin treatment (recombinant rat leptin, 2.5 microg/g.d, sc) from postnatal d 3-13 resulted in a transient slowing of neonatal weight gain, particularly in programmed offspring. Neonatal leptin treatment of male offspring from normally nourished mothers caused an increase in diet-induced weight gain and related metabolic sequelae, including hyperinsulinemia and increased total body adiposity compared with saline-treated controls. This occurred without an increase in caloric intake. These effects were specific to offspring of normal pregnancies and were not observed in offspring of mothers after UN during pregnancy. In the latter, neonatal leptin treatment conferred protection against the development of the programmed phenotype, particularly in those fed the chow diet postnatally. These data further reinforce the importance of leptin in determining long-term energy homeostasis, and suggest that leptin's effects are modulated by gender and both prenatal and postnatal nutritional status.

Prenatal and postnatal pathways to obesity: different underlying mechanisms, different metabolic outcomes.

Obesity and type 2 diabetes are worldwide health issues. The present paper investigates prenatal and postnatal pathways to obesity, identifying different metabolic outcomes with different effects on insulin sensitivity and different underlying mechanisms involving key components of insulin receptor signaling pathways. Pregnant Wistar rats either were fed chow ad libitum or were undernourished throughout pregnancy, generating either control or intrauterine growth restricted (IUGR) offspring. Male offspring were fed either standard chow or a high-fat diet from weaning. At 260 d of age, whole-body insulin sensitivity was assessed by hyperinsulinemic-euglycemic clamp, and other metabolic parameters were measured. As expected, high-fat feeding caused diet-induced obesity (DIO) and insulin resistance. Importantly, the insulin sensitivity of IUGR offspring was similar to that of control offspring, despite fasting insulin hypersecretion and increased adiposity, irrespective of postnatal nutrition. Real-time PCR and Western blot analyses of key markers of insulin sensitivity and metabolic regulation showed that IUGR offspring had increased hepatic levels of atypical protein kinase C zeta (PKC zeta) and increased expression of fatty acid synthase mRNA. In contrast, DIO led to decreased expression of fatty acid synthase mRNA and hepatic steatosis. The decrease in hepatic PKC zeta with DIO may explain, at least in part, the insulin resistance. Our data suggest that the mechanisms of obesity induced by prenatal events are fundamentally different from those of obesity induced by postnatal high-fat nutrition. The origin of insulin hypersecretion in IUGR offspring may be independent of the mechanistic events that trigger the insulin resistance commonly observed in DIO.

Prenatal influences on susceptibility to diet-induced obesity are mediated by altered neuroendocrine gene expression.

The escalating rates of obesity and type 2 diabetes have reached pandemic proportions. It has been proposed that the risk of developing metabolic disorders in adult life is influenced by environmental factors, which operate during the early periods of development. We have previously shown that an interaction between the prenatal and the postnatal dietary environment amplifies the propensity towards diet-induced obesity, although the mechanisms are unclear. In the present study, we investigated the interaction between prenatal undernutrition and postnatal high-fat nutrition on key genes of the hypothalamic appetite regulatory network. Pregnant Wistar rats were fed a standard chow diet either ad libitum (AD) or at 30% of AD intake throughout gestation (UN). From weaning, female AD and UN offspring were fed either a standard chow (ADC n = 8, UNC n = 8) or a high-fat diet (45% kcal as fat; ADHF n = 8, UNHF n = 8) ad libitum for the remainder of the study. At 24 weeks of age, body composition was assessed by dual energy X-ray absorptiometry analysis and total RNA was extracted from whole rat hypothalami. Real-time PCR was performed to characterise pro-opiomelanocortin (POMC), neuropeptide Y (NPY), agouti-related protein (AgRP) and OBRb gene expression at the mRNA level. Our results demonstrate that the amplification of postnatal obesity develops as a consequence of an interaction between prenatal under-nutrition and postnatal high-fat nutrition. This phenotype also shows significant alterations in POMC, NPY, AgRP and OBRb gene expression together with elevations in circulating levels of both plasma leptin and insulin. These findings are consistent with the predictive adaptive response hypothesis that neuroendocrine development during fetal life may be based on predictions about postnatal environmental conditions. Increased susceptibility to diet-induced obesity develops if a mismatch between the anticipated and the actual conditions are encountered.

Maternal nutrition and four-alternative choice.

Two groups of 10 male rats were trained to nose poke for food pellets at four alternatives that provided differing rates of pellet delivery on aperiodic schedules. After a fixed number of pellets had been delivered, 5, 10 or 20 in different conditions of the experiment, a 10-s blackout occurred, and the locations of the differing rates of pellet delivery were randomized for the next component. Two groups of rats were used: The AD group consisted of 10 rats born to dams that had normal (ad libitum) nutrition during pregnancy, whereas the 10 rats in the UN group were from dams exposed to reduced food availability during pregnancy. All pups received normal nutrition after birth. Choice between the nose-poke alternatives quickly adapted when the rates of pellet delivery were changed in both groups, but there were no consistent differences in the speed of adaptation between the two groups. The generalized matching relation failed to describe the allocation of responses among alternatives, but the contingency-discriminability model provided a precise description of performance.

Hyperinsulinemia in cord blood in mothers with type 2 diabetes and gestational diabetes mellitus in New Zealand.

OBJECTIVE: In genetically diabetes-prone populations, maternal diabetes during pregnancy increases the risk of their children developing diabetes and obesity (the vicious cycle of type 2 diabetes). Fetal hyperinsulinemia at birth acts as a marker of this risk. We therefore examined whether cord insulin and leptin concentrations are increased in offspring of Maori and Pacific Island mothers with type 2 and gestational diabetes mellitus (GDM) and varying degrees of glycemic control (HbA(1c)). RESEARCH DESIGNS AND METHODS: Maori and Pacific Island mothers were prospectively recruited at Middlemore Hospital, South Auckland. Cord blood was taken from umbilical vein at birth from singleton babies born after 32 weeks of gestation to 138 mothers with GDM, 39 mothers with type 2 diabetes, and 95 control mothers. RESULTS: Babies born to mothers with both type 2 diabetes and GDM had higher birth weight and skinfold thickness and markedly higher concentrations of insulin (median [interquartile range] type 2 diabetes 77 pmol/l [42-143], GDM 67 pmol/l [42-235], and control subjects 33 pmol/l [18-62]; P < 0.001) and leptin (type 2 diabetes 39 ng/ml [18-75], GDM 31 ng/ml [17-58], and control subjects 13 ng/ml [8-22]; P < 0.001) in cord blood. Cord insulin concentrations >120 pmol/l were found in 29% of offspring of mothers with GDM and 31% of mothers with type 2 diabetes. Many mothers with GDM had abnormalities of glucose tolerance postpartum (20% type 2 diabetes, 34% impaired glucose tolerance or impaired fasting glucose). Higher cord insulin (57 pmol/l [40-94]) and leptin (26 ng/ml [17-39]) concentrations were found even in offspring of GDM mothers with normal glucose tolerance postpartum. CONCLUSIONS: Raised cord insulin and leptin concentrations are a common finding in offspring of mothers with type 2 diabetes and GDM in this population.

Effect of mouth rinsing and ingestion of carbohydrate solutions on mood and perceptual responses during exercise.

BACKGROUND: The aim of this study was to investigate whether mouth rinsing or ingesting carbohydrate (CHO) solutions impact on perceptual responses during exercise. METHODS: Nine moderately trained male cyclists underwent a 90-min glycogen-reducing exercise, and consumed a low CHO meal, prior to completing an overnight fast. A 1-h cycle time trial was performed the following morning. Four trials, each separated by 7 days, were conducted in a randomized, counterbalanced study design: 15% CHO mouth rinse (CHOR), 7.5% CHO ingestion (CHOI), placebo mouth rinse (PLAR) and placebo ingestion (PLAI). Solution volumes (1.5 ml · kg-1 ingestion trials and 0.33 ml · kg-1 rinsing trials) were provided after every 12.5% of completed exercise. Perceptual scales were used to assess affective valence (feeling scale, FS), arousal (felt arousal scale, FAS), exertion (ratings of perceived exertion, RPE) and mood (profile of mood states, POMS) before, during and immediately after exercise. RESULTS: There was no difference in RPE (CHOI, 14.0 ± 1.9; CHOR, 14.2 ± 1.7; PLAI, 14.6 ± 1.8; PLAR, 14.6 ± 2.0; P = 0.35), FS (CHOI, 0.0 ± 1.7; CHOR, -0.2 ± 1.5; PLAI, -0.8 ± 1.4; PLAR, -0.8 ± 1.6; P = 0.15), or FAS (CHOI, 3.6 ± 1.1; CHOR, 3.5 ± 1.0; PLAI, 3.4 ± 1.4; PLAR, 3.3 ± 1.3; P = 0.725) scores between trials. While overall POMS score did not appear to differ between trials, the 'vigour' subscale indicated that CHOI may facilitate the maintenance of 'vigour' scores over time, in comparison to the steady decline witnessed in other trials (P = 0.04). There was no difference in time trial performance between trials (CHOI, 65.3 ± 4.8 min; CHOR, 68.4 ± 3.9 min; PLAI, 68.7 ± 5.3 min; PLAR, 68.3 ± 5.2 min; P = 0.21) but power output was higher in CHOI (231.0 ± 33.2 W) relative to other trials (221-223.6 W; P < 0.01). CONCLUSIONS: In a CHO-reduced state, mouth rinsing with a CHO solution did not impact on perceptual responses during high-intensity exercise in trained cyclists and triathletes. On the other hand CHO ingestion improved perceived ratings of vigour and increased power output during exercise.

Exploring the challenges in obtaining physical activity data from women using hip-worn accelerometers.

Quality objective physical activity data are required to inform physical activity-based health improvement initiatives, however, various challenges undermine acquisition of such data. We examined the efficacy and challenges of a hip-worn accelerometry protocol in women. Specific objectives included determining accelerometer-wear-compliance rates and understanding the barriers and acceptability of wearing accelerometers. Healthy New Zealand women (n = 406) of three ethnicities (Maori (indigenous New Zealander), Pacific, European) aged 16-45 years (30.9 ± 8.7 y) wore hip-mounted Actigraph wGT3X+ accelerometers for 7 consecutive days under a 24-h wear protocol. Post hoc, a sub-sample (n = 45; age: 29.4 ± 9.0 y) was interviewed to investigate comfort/convenience and burdens of accelerometer-wear. Wear-compliance (≥10 h/day, ≥4 day) was 86%. European women returned more valid data (92.7%, p < .04) than Pacific (73.0%) or Maori women (82.1%). Twenty-two participants (5.4%) had completely missing data; 13 due to lost accelerometers. Burden of accelerometer-wear was greatest during sleeping (66.7%) due to discomfort. Embarrassment of accelerometer visibility through clothing and consequent restricted clothing choices caused high burden in social settings (45.2%). Discomfort during sleeping, embarrassment due to perceived appearance in social settings and ethnicity are key factors affecting the efficacy of collecting physical activity data from women using hip-worn accelerometers. Refining accelerometer design to reduce size and subsequently participant burden should improve acceptability and wear-compliance. Increasing overall participant compliance by reducing burden and ensuring appropriate understanding of study aims and relevance should reduce attrition and improve wear-compliance and data quality when collecting accelerometry data from women of different ethnicities.

An innovative team-based weightloss competition to reduce cardiovascular and diabetes risk among Maori and Pacific people: rationale and method for the study and its evaluation.

BACKGROUND: Obesity rates for New Zealand (NZ) Pacific and Maori (NZ indigenous people) are among the highest in the world. Long-term results of weight management programmes for adults have been modest but primarily focused on individuals. This paper describes the rationale and methodology for a trial of a culturally tailored team-based weightloss competition conducted online with community level support. METHODS/DESIGN: A quasi-experimental design was used to compare an intervention and control group. Three six-month competitions with seven teams of seven Maori or Pacific people (N = 147) were run. Eligible participants were: Maori or Pacific, 16 years of age and above, obese (BMI ≥30 kg/m2) and either at risk of or already diagnosed with type 2 diabetes (HbA1c >50 mmol/mol) or cardiovascular disease.The intervention facilitated group use of an internet-based competition offering financial incentives, education and support. The primary outcome was percentage of individual weight lost at 12-months. Secondary outcomes were percentage reduced total cholesterol and glycated haemoglobin (HbA1c). Data collected at baseline, 6-months and 12-months included: height, body weight, blood lipids and HbA1c, eating and dieting habits, family support, food access, alcohol use, nutrition literacy, activity levels, perceptions of weight, stress and sleep, and, perceived contagion effect. Process evaluation tasks will inform acceptability. DISCUSSION: An attractive, easy to understand weight change programme that effectively reduces disease risk among Maori and Pacific is desperately needed. Web-based delivered support and information to largely self-directed teams could also ease exponential rises in costs to the health system. TRIAL REGISTRATION: Trial Id: ACTRN12617000871347.