Low-calorie sweeteners in the human diet: scientific evidence, recommendations, challenges and future needs. A symposium report from the FENS 2019 conference

Overconsumption of free sugars, particularly from sugar-sweetened beverages (SSB), has potential negative health impacts. Implementation of a range of public health strategies is needed to reduce intakes of free sugars, including reducing portion sizes, promoting healthier dietary choices and reformulating foods and beverages. Although low-calorie sweeteners (LCS) are a useful tool for reducing energy intake and control glucose response when consuming sweet foods and drinks, several opinions persist about the adverse health effects of LCS, many of which are based on poor, little or no scientific evidence. This symposium report summarises key messages of the presentations and related discussions delivered at a scientific symposium at the 13th European Nutrition Conference (FENS 2019). These presentations considered the scientific evidence and current recommendations about the use and potential benefits of LCS for human health, with a particular focus on current evidence in relation to body weight and glycaemic control. Many of the studies to date on LCS have focused on low-calorie sweetened beverages (LCSB); however, the psychological and behavioural factors influencing consumer beliefs and consumption of LCSB need to be further explored. Current recommendations for LCS use are described, including the conclusions from a recent expert consensus report identifying the challenges that remain with LCS research. Finally, existing knowledge gaps and future actions are described, as well as two large ongoing research projects: SWITCH and SWEET

Characterizing HMW-GS alleles of decaploid Agropyron elongatum in relation to evolution and wheat breeding

Bread wheat quality is mainly correlated with high molecular weight glutenin subunits (HMW-GS) of endosperm. The number of HMW-GS alleles with good processing quality is limited in bread wheat cultivars, while there are plenty of HMW-GS alleles in wheat-related grasses to exploit. We report here on the cloning and characterization of HMW-GS alleles from the decaploid Agropyron elongatum. Eleven novel HMW-GS alleles were cloned from the grass. Of them, five are x-type and six y-type glutenin subunit genes. Three alleles Aex4, Aey7, and Aey9 showed high similarity with another three alleles from the diploid Lophopyrum elongatum, which provided direct evidence for the Ee genome origination of A. elongatum. It was noted that C-terminal regions of three alleles of the y-type genes Aey8, Aey9, and Aey10 showed more similarity with x-type genes than with other y-type genes. This demonstrates that there is a kind of intermediate state that appeared in the divergence between x- and y-type genes in the HMW-GS evolution. One x-type subunit, Aex4, with an additional cysteine residue, was speculated to be correlated with the good processing quality of wheat introgression lines. Aey4 was deduced to be a chimeric gene from the recombination between another two genes. How the HMW-GS genes of A. elongatum may contribute to the improvement of wheat processing quality are discussed

Overexpression of a Common Wheat Gene TaSnRK2.8 Enhances Tolerance to Drought, Salt and Low Temperature in Arabidopsis

Drought, salinity and low temperatures are major factors limiting crop productivity and quality. Sucrose non-fermenting1-related protein kinase 2 (SnRK2) plays a key role in abiotic stress signaling in plants. In this study, TaSnRK2.8, a SnRK2 member in wheat, was cloned and its functions under multi-stress conditions were characterized. Subcellular localization showed the presence of TaSnRK2.8 in the cell membrane, cytoplasm and nucleus. Expression pattern analyses in wheat revealed that TaSnRK2.8 was involved in response to PEG, NaCl and cold stresses, and possibly participates in ABA-dependent signal transduction pathways. To investigate its role under various environmental stresses, TaSnRK2.8 was transferred to Arabidopsis under control of the CaMV-35S promoter. Overexpression of TaSnRK2.8 resulted in enhanced tolerance to drought, salt and cold stresses, further confirmed by longer primary roots and various physiological characteristics, including higher relative water content, strengthened cell membrane stability, significantly lower osmotic potential, more chlorophyll content, and enhanced PSII activity. Meanwhile, TaSnRK2.8 plants had significantly lower total soluble sugar levels under normal growing conditions, suggesting that TaSnRK2.8 might be involved in carbohydrate metabolism. Moreover, the transcript levels of ABA biosynthesis (ABA1, ABA2), ABA signaling (ABI3, ABI4, ABI5), stress-responsive genes, including two ABA-dependent genes (RD20A, RD29B) and three ABA-independent genes (CBF1, CBF2, CBF3), were generally higher in TaSnRK2.8 plants than in WT/GFP controls under normal/stress conditions. Our results suggest that TaSnRK2.8 may act as a regulatory factor involved in a multiple stress response pathways

Perceived weight-related stigma, loneliness, and mental wellbeing during COVID-19 in people with obesity: A cross-sectional study from ten European countries

Background: Increased weight-related stigma during the COVID-19 pandemic has amplified the need to minimise the impacts on mental wellbeing. We investigated the relationship between the perceived changes in the representation of obesity in the media and mental wellbeing during the pandemic in a sample of people with obesity across 10 European countries. We also investigated the potential moderating effect of loneliness. Methods: Between September to December 2020 during the COVID-19 pandemic, participants reported data on demographics, mental wellbeing (measured by World Health Organisation Five Wellbeing Index and Patient Health Questionaire-4), loneliness (measured by De Jong Gierveld short scale), and perceived change in the representation of obesity in media (measured by a study-specific question) using the online, cross-sectional EURopean Obesity PatiEnt pANdemic Survey (EUROPEANS). Data were analysed using linear mixed-effects models, controlling for age, gender, body mass index, and shielding status, with random incept for country. Results: The survey was completed by 2882 respondents. Most identified as female (56%) and reported their ethnicity as White or White-mix (92%). The total sample had a mean age of 41 years and a BMI of 35.4 kg/m2. During the peak of the pandemic, compared to pre-pandemic, perceiving more negative representation of people with obesity on social media was associated with worse psychological distress, depression, and wellbeing. Perceiving more positive representation, compared to no change in representation, of people with obesity on television was associated with greater wellbeing, yet also higher psychological distress and anxiety. Loneliness, as a moderator, explained ≤0.3% of the variance in outcomes in any of the models. Conclusions: Perceiving negative representation of obesity on social media was associated with poorer mental wellbeing outcomes during the pandemic; positive representation on television was associated with both positive and negative mental wellbeing outcomes. We encourage greater media accountability when representing people with obesity

The views of teenagers with obesity, their caregivers, and doctors: a plain language summary of the ACTION Teens global survey.

What is this summary about? This is a summary of a research survey called ACTION Teens. In our survey, 12,987 people from 10 countries answered questions about obesity. They were: 5275 teenagers with obesity, 5389 caregivers of teenagers with obesity, and 2323 doctors who provide medical care for teenagers with obesity. What were the main results of the survey? Most teenagers with obesity were worried about their weight and thought that losing weight was their responsibility. Many teenagers had already tried to lose weight. For teenagers, wanting to be more fit or in better shape was the top reason for wanting to lose weight. Some caregivers did not realize how worried their teenager was about their own weight. There were also some caregivers who were not aware of their teenager's recent attempts to lose weight. As a group, the doctors did not know the main reasons why teenagers want to lose weight. They also did not know the main reasons preventing teenagers from losing weight. What do the results of the survey mean? Teenagers with obesity will be better supported and understood if there is better communication between teenagers, caregivers, and doctors

Cloning of cDNA and chromosomal location of genes encoding the three types of subunits of the wheat tetrameric inhibitor of insect a-amylase

We have characterized three cDNA clones corresponding to proteins CM1, CM3 and CM16, which represent the three types of subunits of the wheat tetrameric inhibitor of insect -amylases. The deduced amino acid sequences of the mature polypeptides are homologous to those of the dimeric and monomeric -amylase inhibitors and of the trypsin inhibitors. The mature polypeptides are preceded by typical signal peptides. Southern blot analysis of appropriate aneuploids, using the cloned cDNAs as probes, has revealed the location of genes for subunits of the CM3 and of the CM16 type within a few kb of each other in chromosomes 4A, 4B and 4D, and those for the CM1 type of subunit in chromosomes 7A, 7B and 7D. Known subunits of the tetrameric inhibitor corresponding to genes from the B and D genomes have been previously characterized. No proteins of this class have been found to be encoded by the A genome in hexaploid wheat (genomes AA, BB, DD) or in diploid wheats (AA) and no anti -amylase activity has been detected in the latter, so that the A-genome genes must be either silent (pseudogenes) or expressed at a much lower level

Modelling the associations between fat-free mass, resting metabolic rate and energy intake in the context of total energy balance

© 2016 Macmillan Publishers Limited.The relationship between body composition, energy expenditure and ad libitum energy intake (EI) has rarely been examined under conditions that allow any interplay between these variables to be disclosed.Objective:The present study examined the relationships between body composition, energy expenditure and EI under controlled laboratory conditions in which the energy density and macronutrient content of the diet varied freely as a function of food choice.Methods:Fifty-nine subjects (30 men: mean body mass index=26.7±4.0 kg m-2; 29 women: mean body mass index=25.4±3.5 kg m-2) completed a 14-day stay in a residential feeding behaviour suite. During days 1 and 2, subjects consumed a fixed diet designed to maintain energy balance. On days 3-14, food intake was covertly measured in subjects who had ad libitum access to a wide variety of foods typical of their normal diets. Resting metabolic rate (RMR; respiratory exchange), total daily energy expenditure (doubly labelled water) and body composition (total body water estimated from deuterium dilution) were measured on days 3-14.Results:Hierarchical multiple regression indicated that after controlling for age and sex, both fat-free mass (FFM; P<0.001) and RMR (P<0.001) predicted daily EI. However, a mediation model using path analysis indicated that the effect of FFM (and fat mass) on EI was fully mediated by RMR (P<0.001).Conclusions:These data indicate that RMR is a strong determinant of EI under controlled laboratory conditions where food choice is allowed to freely vary and subjects are close to energy balance. Therefore, the conventional adipocentric model of appetite control should be revised to reflect the influence of RMR

Signaling Role of Fructose Mediated by FINS1/FBP in Arabidopsis thaliana

Sugars are evolutionarily conserved signaling molecules that regulate the growth and development of both unicellular and multicellular organisms. As sugar-producing photosynthetic organisms, plants utilize glucose as one of their major signaling molecules. However, the details of other sugar signaling molecules and their regulatory factors have remained elusive, due to the complexity of the metabolite and hormone interactions that control physiological and developmental programs in plants. We combined information from a gain-of-function cell-based screen and a loss-of-function reverse-genetic analysis to demonstrate that fructose acts as a signaling molecule in Arabidopsis thaliana. Fructose signaling induced seedling developmental arrest and interacted with plant stress hormone signaling in a manner similar to that of glucose. For fructose signaling responses, the plant glucose sensor HEXOKINASE1 (HXK1) was dispensable, while FRUCTOSE INSENSITIVE1 (FINS1), a putative FRUCTOSE-1,6-BISPHOSPHATASE, played a crucial role. Interestingly, FINS1 function in fructose signaling appeared to be independent of its catalytic activity in sugar metabolism. Genetic analysis further indicated that FINS1–dependent fructose signaling may act downstream of the abscisic acid pathway, in spite of the fact that HXK1–dependent glucose signaling works upstream of hormone synthesis. Our findings revealed that multiple layers of controls by fructose, glucose, and abscisic acid finely tune the plant autotrophic transition and modulate early seedling establishment after seed germination