-
1.
Understanding the role of the gut in undernutrition: what can technology tell us?
Thompson, AJ, Bourke, CD, Robertson, RC, Shivakumar, N, Edwards, CA, Preston, T, Holmes, E, Kelly, P, Frost, G, Morrison, DJ, et al
Gut. 2021;(8):1580-94
-
-
Free full text
-
Abstract
Gut function remains largely underinvestigated in undernutrition, despite its critical role in essential nutrient digestion, absorption and assimilation. In areas of high enteropathogen burden, alterations in gut barrier function and subsequent inflammatory effects are observable but remain poorly characterised. Environmental enteropathy (EE)-a condition that affects both gut morphology and function and is characterised by blunted villi, inflammation and increased permeability-is thought to play a role in impaired linear growth (stunting) and severe acute malnutrition. However, the lack of tools to quantitatively characterise gut functional capacity has hampered both our understanding of gut pathogenesis in undernutrition and evaluation of gut-targeted therapies to accelerate nutritional recovery. Here we survey the technology landscape for potential solutions to improve assessment of gut function, focussing on devices that could be deployed at point-of-care in low-income and middle-income countries (LMICs). We assess the potential for technological innovation to assess gut morphology, function, barrier integrity and immune response in undernutrition, and highlight the approaches that are currently most suitable for deployment and development. This article focuses on EE and undernutrition in LMICs, but many of these technologies may also become useful in monitoring of other gut pathologies.
-
2.
Moderate intensity exercise training combined with inulin-propionate ester supplementation increases whole body resting fat oxidation in overweight women.
Malkova, D, Polyviou, T, Rizou, E, Gerasimidis, K, Chambers, ES, Preston, T, Tedford, MC, Frost, G, Morrison, DJ
Metabolism: clinical and experimental. 2020;:154043
Abstract
BACKGROUND Our previous work has shown that oral supplementation with inulin propionate ester (IPE) reduces intra-abdominal fat and prevents weight gain and that oral propionate intake enhances resting fat oxidation. The effects of IPE combined with exercise training on energy substrate utilisation are unknown. The aim of this study was to investigate the impact of 4-weeks IPE supplementation, in combination with a moderate intensity exercise training programme, on whole body fat oxidation and on plasma GLP-1 and PYY. METHODS Twenty overweight healthy women participated in randomised parallel study and underwent 4 weeks of supervised exercise training either with IPE (EX/IPE group) or Placebo (EX/Placebo group) supplementation. Before and after the intervention participants conducted an experimental trial, which involved collection of expired gas and blood samples in the fasted state and during 7 h of the postprandial state. RESULTS Within groups, the EX/IPE group significantly enhanced the amount of fat (Pre, 24.1 ± 1.2 g; Post, 35.9 ± 4.0 g, P < 0.05) oxidised and reduced CHO (Pre, 77.8 ± 6.0 g; Post, 57.8 ± 7.7 g, P < 0.05) oxidised, reduced body weight (Pre, 77.3 ± 4.2 kg; Post, 76.6 ± 4.1 kg, P < 0.05) and body fat mass (Pre, 37.7 ± 1.9%; Post, 36.9 ± 1.9%, P < 0.05). In EX/Placebo group, changes in amount of fat (Pre, 36.8 ± 3.9 g; Post, 37.0 ± 4.0 g) and CHO (Pre, 62.7 ± 6.5 g; Post, 61.5 ± 7.4 g) oxidised, body weight (Pre, 84.2 ± 4.3 kg; Post, 83.6 ± 4.3 kg) and body fat mass (Pre, 40.1 ± 1.9%; Post, 38.7 ± 1.5%) were not significant (P > 0.05). Comparing between groups, changes in the amount of fat oxidised were significantly (P < 0.05) different and a trend for difference was observed for amount of CHO oxidised (P = 0.06) and RER (P = 0.06). The interventions had no impact on fasting or postprandial plasma concentrations of GLP-1 and PYY. CONCLUSION Moderate intensity exercise training programmes when combined with daily oral IPE supplementation may help overweight women to achieve increase in fat oxidation. The study was registered at clinicaltrials.gov as NCT04016350.
-
3.
Amino Acid Digestibility of Extruded Chickpea and Yellow Pea Protein is High and Comparable in Moderately Stunted South Indian Children with Use of a Dual Stable Isotope Tracer Method.
Devi, S, Varkey, A, Dharmar, M, Holt, RR, Allen, LH, Sheshshayee, MS, Preston, T, Keen, CL, Kurpad, AV
The Journal of nutrition. 2020;(5):1178-1185
-
-
Free full text
-
Abstract
BACKGROUND Legumes are an excellent plant source of the limiting indispensable amino acid (IAA) lysine in vegetarian, cereal-based diets. However, their digestibility is poor largely because of their antiprotease content. Extrusion can enhance digestibility by inactivating trypsin inhibitors and thus potentially improve the protein quality of legumes. OBJECTIVE We measured the digestibility of extruded chickpea and yellow pea protein with use of a dual stable isotope method in moderately stunted South Indian primary school children. METHODS Twenty-eight moderately stunted children (height-for-age z scores <-2.0 SD and >-3.0 SD) aged 6-11 y from low to middle socioeconomic status were randomly assigned to receive a test protein (extruded intrinsically [2H]-labeled chickpea or yellow pea) along with a standard of U-[13C]-spirulina protein to measure amino acid (AA) digestibility with use of a dual stable isotope method. Individual AA digestibility in the test protein was calculated by the ratios of AA enrichments in the test protein to the standard protein in the food and their appearance in blood plasma collected at 6 and 6.5 h during the experiment, representing a plateau state. RESULTS The mean AA digestibility of extruded chickpea and yellow pea protein in moderately stunted children (HAZ; -2.86 to -1.2) was high and similar in both extruded test proteins (89.0% and 88.0%, respectively, P = 0.83). However, lysine and proline digestibilities were higher in extruded chickpea than yellow pea (79.2% compared with 76.5% and 75.0% compared with 72.0%, respectively, P < 0.02). CONCLUSION Extruded chickpea and yellow pea protein had good IAA digestibility in moderately stunted children, which was 20% higher than an earlier report of their digestibility when pressure-cooked, measured by the same method in adults. Higher digestibility of lysine and proline highlights better retention of these AA in chickpea during extrusion-based processing. Extrusion might be useful for developing high-quality protein foods from legumes. This trial was registered at www.ctri.nic.in as CTRI/2018/03/012439.
-
4.
Dietary supplementation with inulin-propionate ester or inulin improves insulin sensitivity in adults with overweight and obesity with distinct effects on the gut microbiota, plasma metabolome and systemic inflammatory responses: a randomised cross-over trial.
Chambers, ES, Byrne, CS, Morrison, DJ, Murphy, KG, Preston, T, Tedford, C, Garcia-Perez, I, Fountana, S, Serrano-Contreras, JI, Holmes, E, et al
Gut. 2019;68(8):1430-1438
-
-
-
Free full text
-
Plain language summary
Literature shows that higher intakes of dietary fibre are associated with a reduced risk of type 2 diabetes. The main aim of this study was to elucidate the underlying mechanisms behind improvements in glucose homeostasis following long-term delivery of propionate (a short-chain fatty acid produced by human gut microbiota in response to dietary fibre) to the human colon. The study is a randomised, double-blind, placebo-controlled cross over trial. Fourteen participants randomly received 20 g/day of a low-fermentable fibre control, a high-fermentable fibre control and inulin-propionate ester (IPE) for 42 days each. Results indicate that stool concentrations of short-chain fatty acids were not different following the three supplementation periods. Furthermore, dietary supplementation with 20 g/day IPE promoted no superior impacts on measures of glucose homeostasis compared with inulin (high-fermentable fibre), yet both IPE and inulin improved insulin resistance relative to cellulose (low-fermentable fibre). Authors conclude that manipulating the colonic fermentation profile of a dietary fibre in favour of propionate promotes selective effects on the mechanisms that contribute to metabolic dysregulation.
Abstract
OBJECTIVE To investigate the underlying mechanisms behind changes in glucose homeostasis with delivery of propionate to the human colon by comprehensive and coordinated analysis of gut bacterial composition, plasma metabolome and immune responses. DESIGN Twelve non-diabetic adults with overweight and obesity received 20 g/day of inulin-propionate ester (IPE), designed to selectively deliver propionate to the colon, a high-fermentable fibre control (inulin) and a low-fermentable fibre control (cellulose) in a randomised, double-blind, placebo-controlled, cross-over design. Outcome measurements of metabolic responses, inflammatory markers and gut bacterial composition were analysed at the end of each 42-day supplementation period. RESULTS Both IPE and inulin supplementation improved insulin resistance compared with cellulose supplementation, measured by homeostatic model assessment 2 (mean±SEM 1.23±0.17 IPE vs 1.59±0.17 cellulose, p=0.001; 1.17±0.15 inulin vs 1.59±0.17 cellulose, p=0.009), with no differences between IPE and inulin (p=0.272). Fasting insulin was only associated positively with plasma tyrosine and negatively with plasma glycine following inulin supplementation. IPE supplementation decreased proinflammatory interleukin-8 levels compared with cellulose, while inulin had no impact on the systemic inflammatory markers studied. Inulin promoted changes in gut bacterial populations at the class level (increased Actinobacteria and decreased Clostridia) and order level (decreased Clostridiales) compared with cellulose, with small differences at the species level observed between IPE and cellulose. CONCLUSION These data demonstrate a distinctive physiological impact of raising colonic propionate delivery in humans, as improvements in insulin sensitivity promoted by IPE and inulin were accompanied with different effects on the plasma metabolome, gut bacterial populations and markers of systemic inflammation.
-
5.
The effects of dietary supplementation with inulin and inulin-propionate ester on hepatic steatosis in adults with non-alcoholic fatty liver disease.
Chambers, ES, Byrne, CS, Rugyendo, A, Morrison, DJ, Preston, T, Tedford, C, Bell, JD, Thomas, L, Akbar, AN, Riddell, NE, et al
Diabetes, obesity & metabolism. 2019;21(2):372-376
-
-
-
Free full text
-
Plain language summary
Non-alcoholic fatty liver disease (NAFLD) is characterised by an accumulation of fat within the liver, and is strongly associated with obesity. Recent investigations suggest that diet, the gut microbiota and liver fat storage could be linked through a mechanism involving short chain fatty acids (SCFA), in particular the SCFA propionate, which are produced by the gut bacteria. The aim of this randomised controlled study was to evaluate whether an inulin-propionate ester (IPE) has benefits in patients with NAFLD. Subjects with NAFLD received either 20 g/d of inulin (control) or IPE for 42 days. 18 subjects completed the trial. Intrahepatocellular lipids IHCL (a marker of fat accumulation in the liver) increased post supplementation in both groups with no significant difference between control and IPE group. There was a change in insulin resistance (HOMA-IR) which was significantly different between groups, with a non-significant increase in the inulin-control group and decrease in the IPE group. There were no within- or between-group differences in body composition. The authors discuss these unexpected results and suggest that the SCFA acetate, from inulin fermentation by gut bacteria, may have led to an increase in IHCL which was attenuated by the propionate.
Abstract
The short chain fatty acid (SCFA) propionate, produced through fermentation of dietary fibre by the gut microbiota, has been shown to alter hepatic metabolic processes that reduce lipid storage. We aimed to investigate the impact of raising colonic propionate production on hepatic steatosis in adults with non-alcoholic fatty liver disease (NAFLD). Eighteen adults were randomized to receive 20 g/d of an inulin-propionate ester (IPE), designed to deliver propionate to the colon, or an inulin control for 42 days in a parallel design. The change in intrahepatocellular lipid (IHCL) following the supplementation period was not different between the groups (P = 0.082), however, IHCL significantly increased within the inulin-control group (20.9% ± 2.9% to 26.8% ± 3.9%; P = 0.012; n = 9), which was not observed within the IPE group (22.6% ± 6.9% to 23.5% ± 6.8%; P = 0.635; n = 9). The predominant SCFA from colonic fermentation of inulin is acetate, which, in a background of NAFLD and a hepatic metabolic profile that promotes fat accretion, may provide surplus lipogenic substrate to the liver. The increased colonic delivery of propionate from IPE appears to attenuate this acetate-mediated increase in IHCL.
-
6.
Effects of Inulin Propionate Ester Incorporated into Palatable Food Products on Appetite and Resting Energy Expenditure: A Randomised Crossover Study.
Byrne, CS, Chambers, ES, Preston, T, Tedford, C, Brignardello, J, Garcia-Perez, I, Holmes, E, Wallis, GA, Morrison, DJ, Frost, GS
Nutrients. 2019;(4)
Abstract
Supplementation with inulin-propionate ester (IPE), which delivers propionate to the colon, suppresses ad libitum energy intake and stimulates the release of satiety hormones acutely in humans, and prevents weight gain. In order to determine whether IPE remains effective when incorporated into food products (FP), IPE needs to be added to a widely accepted food system. A bread roll and fruit smoothie were produced. Twenty-one healthy overweight and obese humans participated. Participants attended an acclimatisation visit and a control visit where they consumed un-supplemented food products (FP). Participants then consumed supplemented-FP, containing 10 g/d inulin or IPE for six days followed by a post-supplementation visit in a randomised crossover design. On study visits, supplemented-FP were consumed for the seventh time and ad libitum energy intake was assessed 420 min later. Blood samples were collected to assess hormones and metabolites. Resting energy expenditure (REE) was measured using indirect calorimetry. Taste and appearance ratings were similar between FP. Ad libitum energy intake was significantly different between treatments, due to a decreased intake following IPE-FP. These observations were not related to changes in blood hormones and metabolites. There was an increase in REE following IPE-FP. However, this effect was lost after correcting for changes in fat free mass. Our results suggest that IPE suppresses appetite and may alter REE following its incorporation into palatable food products.
-
7.
True ileal digestibility of legumes determined by dual-isotope tracer method in Indian adults.
Kashyap, S, Varkey, A, Shivakumar, N, Devi, S, Reddy B H, R, Thomas, T, Preston, T, Sreeman, S, Kurpad, AV
The American journal of clinical nutrition. 2019;(4):873-882
-
-
Free full text
-
Abstract
BACKGROUND Good-quality plant protein sources are important for protein adequacy in a balanced diet. Legumes are known to be a source of good quality plant protein, but the true ileal digestibility of indispensable amino acids (IAAs) of commonly consumed legumes is not known in humans. OBJECTIVES In this study we measured the true ileal IAA digestibility of 2H-intrinsically labeled chickpea, yellow pea, and mung bean (hulled and dehulled) protein, using the dual-isotope tracer technique referenced to a standard protein ([U-13C] spirulina). The study also aimed to validate the use of [U-13C] spirulina as a reference protein in this method. METHODS 2H-intrinsically labeled legumes, obtained by watering plants with deuterium oxide (2H2O), were administered in a plateau feeding method to healthy Indian adults to measure their true ileal IAA digestibility with the dual-isotope tracer technique, using [U-13C] spirulina protein or a 13C-algal IAA mixture as the standard. RESULT The true ileal IAA digestibilities (mean ± SD) of chickpea, yellow pea, and mung bean were 74.6 ± 0.8%, 71.6 ± 1.3%, and 63.2 ± 1.5%, respectively. The true mean ileal IAA digestibility of mung bean when referenced to [U-13C] spirulina protein or a 13C-algal IAA mixture did not differ significantly (63.2 ± 1.5% versus 64.0 ± 2.4%, P > 0.05). The true ileal IAA digestibility of mung bean improved to 70.9 ± 2.1% after dehulling. CONCLUSIONS The true mean ileal IAA digestibility of legumes in healthy Indian adults was lower than expected. Traditional processing techniques such as dehulling improve protein digestibility by about 8%. This study was registered in the Clinical Trials Registry of India (CTRI): CTRI/2017/11/010468 (http://ctri.nic.in, accessed on 28/03/2019).
-
8.
Carbohydrate dose influences liver and muscle glycogen oxidation and performance during prolonged exercise.
King, AJ, O'Hara, JP, Morrison, DJ, Preston, T, King, RFGJ
Physiological reports. 2018;(1)
Abstract
This study investigated the effect of carbohydrate (CHO) dose and composition on fuel selection during exercise, specifically exogenous and endogenous (liver and muscle) CHO oxidation. Ten trained males cycled in a double-blind randomized order on 5 occasions at 77% V˙O2max for 2 h, followed by a 30-min time-trial (TT) while ingesting either 60 g·h-1 (LG) or 75 g·h-113 C-glucose (HG), 90 g·h-1 (LGF) or 112.5 g·h-113 C-glucose-13 C-fructose ([2:1] HGF) or placebo. CHO doses met or exceed reported intestinal transporter saturation for glucose and fructose. Indirect calorimetry and stable mass isotope [13 C] tracer techniques were utilized to determine fuel use. TT performance was 93% "likely/probable" to be improved with LGF compared with the other CHO doses. Exogenous CHO oxidation was higher for LGF and HGF compared with LG and HG (ES > 1.34, P < 0.01), with the relative contribution of LGF (24.5 ± 5.3%) moderately higher than HGF (20.6 ± 6.2%, ES = 0.68). Increasing CHO dose beyond intestinal saturation increased absolute (29.2 ± 28.6 g·h-1 , ES = 1.28, P = 0.06) and relative muscle glycogen utilization (9.2 ± 6.9%, ES = 1.68, P = 0.014) for glucose-fructose ingestion. Absolute muscle glycogen oxidation between LG and HG was not significantly different, but was moderately higher for HG (ES = 0.60). Liver glycogen oxidation was not significantly different between conditions, but absolute and relative contributions were moderately attenuated for LGF (19.3 ± 9.4 g·h-1 , 6.8 ± 3.1%) compared with HGF (30.5 ± 17.7 g·h-1 , 10.1 ± 4.0%, ES = 0.79 & 0.98). Total fat oxidation was suppressed in HGF compared with all other CHO conditions (ES > 0.90, P = 0.024-0.17). In conclusion, there was no linear dose response for CHO ingestion, with 90 g·h-1 of glucose-fructose being optimal in terms of TT performance and fuel selection.
-
9.
The effect of L-rhamnose on intestinal transit time, short chain fatty acids and appetite regulation: a pilot human study using combined 13CO2/H2 breath tests.
Byrne, CS, Preston, T, Brignardello, J, Garcia-Perez, I, Holmes, E, Frost, GS, Morrison, DJ
Journal of breath research. 2018;(4):046006
-
-
Free full text
-
Abstract
BACKGROUND The appetite-regulating effects of non-digestible carbohydrates (NDC) have in part previously been attributed to their effects on intestinal transit rates as well as microbial production of short chain fatty acids (SCFA). Increased colonic production of the SCFA propionate has been shown to reduce energy intake and stimulate gut hormone secretion acutely in humans. OBJECTIVE We investigated the effect of the propiogenic NDC, L-rhamnose, on gastrointestinal transit times using a combined 13CO2/H2 breath test. We hypothesised that L-rhamnose would increase plasma propionate leading to a reduction in appetite, independent of changes in gastrointestinal transit times. DESIGN We used a dual 13C-octanoic acid/lactose 13C-ureide breath test combined with breath H2 to measure intestinal transit times following the consumption of 25 g d-1 L-rhamnose, compared with inulin and cellulose, in 10 healthy humans in a randomised cross-over design pilot study. Gastric emptying (GE) and oro-caecal transit times (OCTTs) were derived from the breath 13C data and compared with breath H2. Plasma SCFA and peptide YY (PYY) were also measured alongside subjective measures of appetite. RESULTS L-rhamnose significantly slowed GE rates (by 19.5 min) but there was no difference in OCTT between treatments. However, breath H2 indicated fermentation of L-rhamnose before it reached the caecum. OCTT was highly correlated with breath H2 for inulin but not for L-rhamnose or cellulose. L-rhamnose consumption significantly increased plasma propionate and PYY but did not significantly reduce subjective appetite measures. CONCLUSIONS The NDCs tested had a minimal effect on intestinal transit time. Our data suggest that L-rhamnose is partially fermented in the small intestine and that breath H2 reflects the site of gastrointestinal fermentation and is only a reliable marker of OCTT for certain NDCs (e.g. inulin). Future studies should focus on investigating the appetite-suppressing potential of L-rhamnose and verifying the findings in a larger cohort.
-
10.
Collision activity during training increases total energy expenditure measured via doubly labelled water.
Costello, N, Deighton, K, Preston, T, Matu, J, Rowe, J, Sawczuk, T, Halkier, M, Read, DB, Weaving, D, Jones, B
European journal of applied physiology. 2018;(6):1169-1177
-
-
Free full text
-
Abstract
PURPOSE Collision sports are characterised by frequent high-intensity collisions that induce substantial muscle damage, potentially increasing the energetic cost of recovery. Therefore, this study investigated the energetic cost of collision-based activity for the first time across any sport. METHODS Using a randomised crossover design, six professional young male rugby league players completed two different 5-day pre-season training microcycles. Players completed either a collision (COLL; 20 competitive one-on-one collisions) or non-collision (nCOLL; matched for kinematic demands, excluding collisions) training session on the first day of each microcycle, exactly 7 days apart. All remaining training sessions were matched and did not involve any collision-based activity. Total energy expenditure was measured using doubly labelled water, the literature gold standard. RESULTS Collisions resulted in a very likely higher (4.96 ± 0.97 MJ; ES = 0.30 ± 0.07; p = 0.0021) total energy expenditure across the 5-day COLL training microcycle (95.07 ± 16.66 MJ) compared with the nCOLL training microcycle (90.34 ± 16.97 MJ). The COLL training session also resulted in a very likely higher (200 ± 102 AU; ES = 1.43 ± 0.74; p = 0.007) session rating of perceived exertion and a very likely greater (- 14.6 ± 3.3%; ES = - 1.60 ± 0.51; p = 0.002) decrease in wellbeing 24 h later. CONCLUSIONS A single collision training session considerably increased total energy expenditure. This may explain the large energy expenditures of collision-sport athletes, which appear to exceed kinematic training and match demands. These findings suggest fuelling professional collision-sport athletes appropriately for the "muscle damage caused" alongside the kinematic "work required".