Showing papers by "Catherine Hambly published in 2017"

Reconstitution of UCP1 using CRISPR/Cas9 in the white adipose tissue of pigs decreases fat deposition and improves thermogenic capacity

Abstract: Uncoupling protein 1 (UCP1) is localized on the inner mitochondrial membrane and generates heat by uncoupling ATP synthesis from proton transit across the inner membrane. UCP1 is a key element of nonshivering thermogenesis and is most likely important in the regulation of body adiposity. Pigs (Artiodactyl family Suidae) lack a functional UCP1 gene, resulting in poor thermoregulation and susceptibility to cold, which is an economic and pig welfare issue owing to neonatal mortality. Pigs also have a tendency toward fat accumulation, which may be linked to their lack of UCP1, and thus influences the efficiency of pig production. Here, we report application of a CRISPR/Cas9-mediated, homologous recombination (HR)-independent approach to efficiently insert mouse adiponectin-UCP1 into the porcine endogenous UCP1 locus. The resultant UCP1 knock-in (KI) pigs showed an improved ability to maintain body temperature during acute cold exposure, but they did not have alterations in physical activity levels or total daily energy expenditure (DEE). Furthermore, ectopic UCP1 expression in white adipose tissue (WAT) dramatically decreased fat deposition by 4.89% (P < 0.01), consequently increasing carcass lean percentage (CLP; P < 0.05). Mechanism studies indicated that the loss of fat upon UCP1 activation in WAT was linked to elevated lipolysis. UCP1 KI pigs are a potentially valuable resource for agricultural production through their combination of cold adaptation, which improves pig welfare and reduces economic losses, with reduced fat deposition and increased lean meat production.

Energy Intake and Expenditure of Professional Soccer Players of the English Premier League: Evidence of Carbohydrate Periodization

Abstract: In an attempt to better identify and inform the energy requirements of elite soccer players, we quantified the energy expenditure (EE) of players from the English Premier League (n = 6) via the doubly labeled water method (DLW) over a 7-day in-season period. Energy intake (EI) was also assessed using food diaries, supported by the remote food photographic method and 24 hr recalls. The 7-day period consisted of 5 training days (TD) and 2 match days (MD). Although mean daily EI (3186 ± 367 kcals) was not different from (p > .05) daily EE (3566 ± 585 kcals), EI was greater (p < .05) on MD (3789 ± 532 kcal; 61.1 ± 11.4 kcal.kg-1 LBM) compared with TD (2956 ± 374 kcal; 45.2 ± 9.3 kcal.kg-1 LBM, respectively). Differences in EI were reflective of greater (p < .05) daily CHO intake on MD (6.4 ± 2.2 g.kg-1) compared with TD (4.2 ± 1.4 g.kg-1). Exogenous CHO intake was also different (p < .01) during training sessions (3.1 ± 4.4 g.h-1) versus matches (32.3 ± 21.9 g.h-1). In contrast, daily protein (205 ± 30 g.kg-1, p = .29) and fat intake (101 ± 20 g, p = .16) did not display any evidence of daily periodization as opposed to g.kg-1, Although players readily achieve current guidelines for daily protein and fat intake, data suggest that CHO intake on the day before and in recovery from match play was not in accordance with guidelines to promote muscle glycogen storage.

Seasonal changes in energy expenditure, body temperature and activity patterns in llamas (Lama glama).

Abstract: Mammals typically keep their body temperature (Tb) within a narrow limit with changing environmental conditions. There are indications that some wild ungulates can exhibit certain forms of energy saving mechanisms when ambient temperatures are low and/or food is scarce. Therefore, the aim of the study was to determine if the llama, one of the most extensively kept domestic livestock species, exhibits seasonal adjustment mechanisms in terms of energy expenditure, Tb and locomotion. For that purpose llamas (N = 7) were kept in a temperate habitat on pasture. Locomotor activity, Tb (measured in the rumen) and the location of each animal were recorded continuously for one year using a telemetry system. Daily energy expenditure was measured as field metabolic rate (FMR). FMR fluctuated considerably between seasons with the lowest values found in winter (17.48 ± 3.98 MJ d−1, 402 kJ kg−0.75 d−1) and the highest in summer (25.87 ± 3.88 MJ d−1, 586 kJ kg−0.75 d−1). Llamas adjusted their energy expenditure, Tb and locomotor activity according to season and also time of day. Thus, llamas seem to have maintained the ability to reduce their energy expenditure and adjust their Tb under adverse environmental conditions as has been reported for some wild ungulates.

Daily energy expenditure in the face of predation: hedgehog energetics in rural landscapes.

Abstract: This research was funded by a grant from the People's Trust for Endangered Species and the British Hedgehog Preservation Society.

The validity of a web-based FFQ assessed by doubly labelled water and multiple 24-h recalls.

Abstract: The aim of this study was to validate the estimated habitual dietary intake from a newly developed web-based FFQ (WebFFQ), for use in an adult population in Norway. In total, ninety-two individuals were recruited. Total energy expenditure (TEE) measured by doubly labelled water was used as the reference method for energy intake (EI) in a subsample of twenty-nine women, and multiple 24-h recalls (24HR) were used as the reference method for the relative validation of macronutrients and food groups in the entire sample. Absolute differences, ratios, crude and deattenuated correlations, cross-classifications, Bland-Altman plot and plots between misreporting of EI (EI-TEE) and the relative misreporting of food groups (WebFFQ-24HR) were used to assess the validity. Results showed that EI on group level was not significantly different from TEE measured by doubly labelled water (0·7 MJ/d), but ranking abilities were poor (r -0·18). The relative validation showed an overestimation for the majority of the variables using absolute intakes, especially for the food groups 'vegetables' and 'fish and shellfish', but an improved agreement between the test and reference tool was observed for energy adjusted intakes. Deattenuated correlation coefficients were between 0·22 and 0·89, and low levels of grossly misclassified individuals (0-3 %) were observed for the majority of the energy adjusted variables for macronutrients and food groups. In conclusion, energy estimates from the WebFFQ should be used with caution, but the estimated absolute intakes on group level and ranking abilities seem acceptable for macronutrients and most food groups.

Body macronutrient composition is predicted by lipid and not protein content of the diet.

Abstract: Funded by Natural Environment Research Council. Grant Number: NE/I020245/1 Biotechnology and Biological Sciences Research Council. Grant Number: BB/J01446X/1

Children's perception on healthy snacks using a card sorting exercise in Aberdeenshire nursery and primary schools

Abstract: Children’s knowledge and understanding of a healthy diet is often limited, and the health consequences of eating unhealthy foods appear to be of low priority for children. Most children prefer snacks with high energy density and low nutritional value which may contribute to the rise in obesity during childhood. This cross-sectional study aimed to 1) examine children’s snack preferences and their perception of how healthy snacks are analyzed by age and gender and 2) determine the relationship between children’s snacks preference (using the nutritional composition of energy, fat, sugar and salt content of the 18 snacks) and their health parameters. Children of nursery and primary schools aged 3–12 years old (212 boys and 260 girls) were interviewed at their schools and performed snack card sorting exercises in which they were presented with 18 various types of coloured snack images which counted as one portion in size. A series of ranking questions (most to least) were asked. These included three main snack perception questions, 1) children’s snack preferences; 2) children’s perception of their parents snack preferences for them; 3) children’s perception of the snacks healthiness. Health parameters of height, weight, body fat, waist circumference and hip circumference were also measured on the day of the interview. The ranked snacks were replaced by the computed nutritional composition of energy, fat, sugar and salt content of the 18 snacks. The mean of the nutritional composition of the five top and bottom snacks chosen by children was used in the analysis. There was no significant relationship between children’s age and snack preference (linear regression: F(1,469) = 2·758, p = 0·097, r 2 = 0·006) and no gender preferences of all types of snacks (independent t-test: t(469) = 0·293, p = 0·77). The perception of snack healthiness increased with age (F(1,457) = 80·53, p < 0·001, r 2 = 0·15) but there was no gender differences (t(457) = 0·552, p = 0·58). When children were asked about their parent’s snack choices for them, they chose the snacks that they also perceived to be healthiest (linear regression: F(1,16) = 980·61, p < 0·001, r 2 = 0·98). The highest proportion of children brought fruit and vegetables into school as their snack (34%). Children’s with high/low BMI-percentile did not show a specific preference for any snacks however, snacks high in fat and sugar content were preferred by children with higher body fat. Snacks high in energy and fat content was preferred by heavier children and snack high in fat alone was preferred by those with higher in waist circumferences and waist to hip ratio respectively (Multiple regression; adjusted for age, sex and schools, p < 0·001). In conclusion, despite Scottish, nursery and primary age children correctly perceiving what counts as a healthy snack, this perception was not translated into their snacking behaviours. Further nutrition education about healthy eating practices is required, specifically at school.