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Background: Due to the increase in global temperature, it is necessary to investigate solutions so that athletes competing in hot conditions can perform in optimal conditions avoiding loss of performance and health problems. Therefore, this study aims to evaluate the effect of pre-exercise glycerol supplementation during a rectangular test at ambient temperature mid (28.2ºC) on dehydration variables in international race walkers., Methods: Eight international male race walkers (age: 28.0 years (4.4); weight: 65.6 kg (6.6); height: 180.0 cm (5.0); fat mass: 6.72% (0.66); muscle mass: 33.3 kg (3.3); VO 2MAX : 66.5 ml · kg -1 ·min -1 (1.9)) completed this randomized crossover design clinical trial. Subjects underwent two interventions: they consumed placebo ( n  = 8) and glycerol ( n  = 8) acutely, before a rectangular test where dehydration, RPE, metabolic, kinematic, and thermographic variables were analyzed before, during and after the test., Results: After the intervention, significant differences were found between groups in body mass in favor of the placebo (Placebo: -2.23 kg vs Glycerol: -2.48 kg; p  = 0.033). For other variables, no significant differences were found., Conclusion: Therefore, pre-exercise glycerol supplementation was not able to improve any dehydration, metabolic, kinematic, or thermographic variables during a rectangular test at temperature mid in international race walkers. Possibly, a higher environmental temperature could have generated a higher metabolic and thermoregulatory stress, generating differences between groups like other previous scientific evidence.

Aims/hypothesis: As a result of early loss of the glucagon response, adrenaline is the primary counter-regulatory hormone in type 1 diabetes. Diminished adrenaline responses to hypoglycaemia due to counter-regulatory failure are common in type 1 diabetes, and are probably induced by exposure to recurrent hypoglycaemia, however, the metabolic effects of adrenaline have received less research attention, and also there is conflicting evidence regarding adrenaline sensitivity in type 1 diabetes. Thus, we aimed to investigate the metabolic response to adrenaline and explore whether it is modified by prior exposure to hypoglycaemia., Methods: Eighteen participants with type 1 diabetes and nine healthy participants underwent a three-step ascending adrenaline infusion during a hyperinsulinaemic-euglycaemic clamp. Continuous glucose monitoring data obtained during the week before the study day were used to assess the extent of hypoglycaemia exposure., Results: While glucose responses during the clamp were similar between people with type 1 diabetes and healthy participants, plasma concentrations of NEFAs and glycerol only increased in the group with type 1 diabetes (p<0.001). Metabolomics revealed an increase in the most common NEFAs (p<0.01). Other metabolic responses were generally similar between participants with type 1 diabetes and healthy participants. Exposure to hypoglycaemia was negatively associated with the NEFA response; however, this was not statistically significant., Conclusions/interpretation: In conclusion, individuals with type 1 diabetes respond with increased lipolysis to adrenaline compared with healthy participants by mobilising the abundant NEFAs in plasma, whereas other metabolic responses were similar. This may suggest that the metabolic sensitivity to adrenaline is altered in a pathway-specific manner in type 1 diabetes., Trial Registration: ClinicalTrials.gov NCT05095259., (© 2024. The Author(s).)

We evaluated changes in hyperhydration and beverage hydration index (BHI, a composite measure of fluid balance after consuming a test beverage relative to water) during resting, induced by the consumption of beverages containing glycerol and sodium supplemented with fast-absorbing sucrose or slow-absorbing isomaltulose. In a randomized crossover, single-blinded protocol (clinical trials registry: UMIN000042644), 14 young physically active adults (three women) consumed 1 L of beverage containing either 7% glycerol + 0.5% sodium (Gly + Na), Gly + Na plus 7% sucrose (Gly + Na + Suc), Gly + Na plus 7% isomaltulose (Gly + Na + Iso), or water (CON) over a 40 min period. We assessed the change in plasma volume (ΔPV), BHI (calculated from cumulative urine output following consumption of water relative to that of the beverage), and blood glucose and sodium for 180 min after initiating ingestion. Total urine volume was reduced in all beverages containing glycerol and sodium compared to CON (all P  ≤ 0.002). The addition of isomaltulose increased BHI by ∼45% (3.43 ± 1.0 vs. 2.50 ± 0.7 for Gly + Na, P  = 0.011) whereas sucrose did not (2.6 ± 0.6, P  = 0.826). The PV expansion was earliest for Gly + Na (30 min), slower for Gly + Na + Suc (90 min), and slowest for Gly + Na + Iso (120 min) with a concomitant lag in the increase of blood glucose and sodium concentrations. Supplementation of beverages containing glycerol and sodium with isomaltulose but not sucrose enhances BHI from those of glycerol and sodium only under a resting state, likely due to the slow absorption of isomaltulose-derived monosaccharides (i.e., glucose and fructose).

This study investigated if paraxanthine (PX) impacts energy expenditure, lipolysis and perceptual responses. In a randomized, double-blind, placebo-controlled, crossover fashion, 21 adults (13 M, 8 F; 26.0 ± 6.4 years, 174.9 ± 11.5 cm, 81.0 ± 15.7 kg body mass, 26.3 ± 3.4 kg/m 2 ) consumed a placebo (PLA), 100 mg (PX100), 200 mg (PX200), and 300 mg of PX (PX300, enfinity®, Ingenious Ingredients, L.P. Lewisville, TX, USA). Venous blood was collected 0, 30, 60, 90, 120 and 180 min (min) after ingestion and analyzed for glycerol and free fatty acids. Resting hemodynamics, metabolic rate and perceptual indicators of hunger, appetite and anxiety were evaluated. Mixed factorial analysis of variance were used to evaluate changes time within and between groups. Heart rate decreased in PX100 compared to PLA 60 ( p =  .022) and 180 min ( p =  .001). Blood pressure did not change. Hunger ratings in PLA increased 30 ( p  = .05), 60 ( p  = .04), 90 ( p  = .02), and 180 min ( p  = .05) after ingestion when compared to PX200. PX200 increased energy expenditure (all p  < .05) when compared to PLA. Rates of fat oxidation tended to increase 90 ( p  = .056) and 120 min ( p  = .066) in PX200 compared to PLA. Free fatty acids increased in PX300 compared to PLA ( p  = .002). Glycerol did not change. Ingestion of PX200 augmented energy expenditure and hunger ratings when compared to PLA without impacting hemodynamics or lipolysis.

Wild-type (WT) mice maintain viable levels of blood glucose even when adipose stores are depleted by 6 d of 60% calorie restriction followed by a 23-h fast (hereafter designated as "starved" mice). Survival depends on ghrelin, an octanoylated peptide hormone. Mice that lack ghrelin suffer lethal hypoglycemia when subjected to the same starvation regimen. Ghrelin is known to stimulate secretion of growth hormone (GH), which in turn stimulates secretion of IGF-1 (insulin-like growth factor-1). In the current study, we found that starved ghrelin-deficient mice had a 90% reduction in plasma IGF-1 when compared with starved WT mice. Injection of IGF-1 in starved ghrelin-deficient mice caused a twofold increase in glucose production and raised blood glucose to levels seen in starved WT mice. Increased glucose production was accompanied by increases in plasma glycerol, fatty acids and ketone bodies, and hepatic triglycerides. All of these increases were abolished when the mice were treated with atglistatin, an inhibitor of adipose tissue triglyceride lipase. We conclude that IGF-1 stimulates adipose tissue lipolysis in starved mice and that this lipolysis supplies energy and substrates that restore hepatic gluconeogenesis. This action of IGF-1 in starved mice is in contrast to its known action in inhibiting adipose tissue lipase in fed mice. Surprisingly, the ghrelin-dependent maintenance of plasma IGF-1 in starved mice was not mediated by GH. Direct injection of GH into starved ghrelin-deficient mice failed to increase plasma IGF-1. These data call attention to an unsuspected role of IGF-1 in the adaptation to starvation.

Male hypogonadism is a disorder characterized by low levels of testosterone, but patients can either show normal insulin (insulin-sensitive (IS)) or over time they can become insulin-resistant (IR). Since the two groups showed different altered metabolisms, testosterone replacement therapy (TRT) could achieve different results. In this paper, we analyzed plasma from 20 IS patients with low testosterone (<8 nmol/L) and HOMAi < 2.5. The samples, pre- and post-treatment with testosterone for 60 days, were analyzed by UHPLC and mass spectrometry. Glycolysis was significantly upregulated, suggesting an improved glucose utilization. Conversely, the pentose phosphate pathway was reduced, while the Krebs cycle was not used. Branched amino acids and carnosine metabolism were positively influenced, while β-oxidation of fatty acids (FFA) was not activated. Cholesterol, HDL, and lipid metabolism did not show any improvements at 60 days but did so later in the experimental period. Finally, both malate and glycerol shuttle were reduced. As a result, both NADH and ATP were significantly lower. Interestingly, a significant production of lactate was observed, which induced the activation of the Cori cycle between the liver and muscles, which became the main source of energy for these patients without involving alanine. Thus, the treatment must be integrated with chemicals which are not restored in order to reactivate energy production.

Vitamin D is necessary for musculoskeletal health, however, the supplementation of vitamin D above the sufficiency level does not bring additional bone mass density (BMD), unlike physical exercise which enhances the bone formatting process. Regular physical activity has been shown to upregulate VDR expression in muscles and to increase circulating vitamin D. Here we investigate whether a single bout of exercise might change 25(OH)D 3 blood concentration and how it affects metabolic response to exercise. Twenty-six boys, 13.8 years old (SD ± 0.7) soccer players, participated in the study. The participants performed one of two types of exercise: the first group performed the VO 2 max test until exhaustion, and the second performed three times the repeated 30 s Wingate Anaerobic Test (WAnT). Blood was collected before, 15 min and one hour after the exercise. The concentration of 25(OH)D 3 , parathyroid hormone (PTH), interleukin-6 (IL-6), lactate, non-esterified fatty acids (NEFA) and glycerol were determined. 25(OH)D 3 concentration significantly increased after the exercise in all boys. The most prominent changes in 25(OH)D 3 , observed after WAnT, were associated with the rise of PTH. The dimensions of response to the exercises observed through the changes in the concentration of 25(OH)D 3 , PTH, NEFA and glycerol were associated with the significant increases of IL-6 level. A single bout of exercise may increase the serum's 25(OH)D 3 concentration in young trained boys. The intensive interval exercise brings a more potent stimulus to vitamin D fluctuations in young organisms. Our results support the hypothesis that muscles may both store and release 25(OH)D 3 ., (© 2022. The Author(s).)

When plasma triglyceride is assessed in standard laboratories, it is a measurement of plasma glycerol after hydrolysis of triglycerides into fatty acids and glycerol. In most patients, the plasma level of free glycerol will only marginally influence the measurement of plasma triglyceride. However, in rare cases elevated free glycerol concentrations causes pseudohypertriglyceridemia and blanking for free glycerol becomes important. In this study, we investigated the plasma free glycerol level in 100 adult men with mild to moderate hypertriglyceridemia to assess the need for providing a free glycerol measurement in our clinical biochemistry department. The plasma samples were obtained in our blood sampling facility that receives both in- and outpatients. The highest plasma level of free glycerol observed was 300 µmol/L and in 99% of the investigated men the inclusion of plasma free glycerol in the measurement of plasma triglyceride cause a less than 10% false increase in plasma triglyceride. A weak positive correlation between the plasma levels of free glycerol and triglyceride was observed. When subdividing the cohort into mild and moderate hypertriglyceridemia, the positive correlation was only maintained in the moderate hypertriglyceridemia group that also demonstrated a 23% higher plasma glycerol level than men with mild hypertriglyceridemia. We conclude that even though glycerol blanking is relevant in rare occasions, then this study does not support providing such a measurement in our department. The positive correlation between free glycerol and triglyceride in this cohort likely reflects a shared association with metabolic dysregulation.

Background: Decaffeinated green tea extract (dGTE) can increase fat oxidation during leg exercise, but dGTE is unsuitable for many people (e.g., those with injuries/disabilities), and its effects on arm exercise and women are unknown., Methods: Eight adults (23-37 years old, 4 women) performed an incremental arm cycle test to measure peak oxygen uptake (VO 2peak ), followed by four 1-h trials at 50% VO 2peak . Subjects were randomly assigned to 650 mg of dGTE or placebo (PLA) for 4 weeks followed by a 4-week washout and crossover trial. Blood samples were obtained pre-exercise and post-exercise for glycerol and free fatty acid analysis. Respiratory gases were collected continuously., Results: VO 2 showed no differences across trials ((0.83-0.89) ± (0.19-0.25) L/min, p = 0.460), neither did energy expenditure ((264-266) ± (59-77) kcal, p = 0.420) nor fat oxidation (dGTE = 0.11 to 0.12 g/min vs. PLA = 0.10 to 0.09 g/min, p = 0.220). Fat oxidation as percentage of energy expenditure was not different for dGTE vs. PLA (23% ± 12% to 25% ± 11% vs. 23% ± 10% to 21% ± 9%, p = 0.532). Glycerol concentration increased post-exercise in all trials, independent of treatments (pre = (3.4-5.1) ± (0.6-2.6) mg/dL vs. post = (7.9-9.8) ± (2.6-3.7) mg/dL, p = 0.867, η 2  = 0.005 for interaction), as did free fatty acid ((3.5-4.8) ± (1.4-2.2) mg/dL vs. (7.2-9.1) ± (2.6-4.5) mg/dL, p = 0.981, η 2  = 0.000)., Conclusion: Chronic dGTE supplementation had no effect on lipolysis and fat oxidation during arm cycle exercise in men and women., (Copyright © 2019. Production and hosting by Elsevier B.V.)

Background: It is commonly accepted that in obesity free fatty acids (FFA) cause insulin resistance and hyperglycemia, which drives hyperinsulinemia. However, hyperinsulinemia is observed in subjects with normoglycaemia and thus the paradigm above should be reevaluated., Methods: We describe two studies: MD-Lipolysis, a case control study investigating the mechanisms of obesity-driven insulin resistance by a systemic metabolic analysis, measurements of adipose tissue lipolysis by microdialysis, and adipose tissue genomics; and POEM, a cohort study used for validating differences in circulating metabolites in relation to adiposity and insulin resistance observed in the MD-Lipolysis study., Findings: In insulin-resistant obese with normal glycaemia from the MD-Lipolysis study, hyperinsulinemia was associated with elevated FFA. Lipolysis, assessed by glycerol release per adipose tissue mass or adipocyte surface, was similar between obese and lean individuals. Adipose tissue from obese subjects showed reduced expression of genes mediating catecholamine-driven lipolysis, lipid storage, and increased expression of genes driving hyperplastic growth. In the POEM study, FFA levels were specifically elevated in obese-overweight subjects with normal fasting glucose and high fasting levels of insulin and C-peptide., Interpretation: In obese subjects with normal glycaemia elevated circulating levels of FFA at fasting are the major metabolic derangement candidate driving fasting hyperinsulinemia. Elevated FFA in obese with normal glycaemia were better explained by increased fat mass rather than by adipose tissue insulin resistance. These results support the idea that hyperinsulinemia and insulin resistance may develop as part of a homeostatic adaptive response to increased adiposity and FFA., Funding: Swedish-Research-Council (2016-02660); Diabetesfonden (DIA2017-250; DIA2018-384; DIA2020-564); Novo-Nordisk-Foundation (NNF17OC0027458; NNF19OC0057174); Cancerfonden (CAN2017/472; 200840PjF); Swedish-ALF-agreement (2018-74560)., Competing Interests: Declaration of Competing Interest L.M.G holds an employment at AstraZeneca R&D. All other authors declare no competing interest., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

This study investigated the effect of decaffeinated green tea extract (dGTE), with or without antioxidant nutrients, on fat oxidation, body composition and cardio-metabolic health measures in overweight individuals engaged in regular exercise. Twenty-seven participants (20 females, 7 males; body mass: 77.5 ± 10.5 kg; body mass index: 27.4 ± 3.0 kg·m 2 ; peak oxygen uptake (O 2peak ): 30.2 ± 5.8 mL·kg -1 ·min -1 ) were randomly assigned, in a double-blinded manner, either: dGTE (400 mg·d -1 (-)-epigallocatechin-3-gallate (EGCG), n = 9); a novel dGTE+ (400 mg·d -1 EGCG, quercetin (50 mg·d -1 ) and α-lipoic acid (LA, 150 mg·d -1 ), n = 9); or placebo (PL, n = 9) for 8 weeks, whilst maintaining standardised, aerobic exercise. Fat oxidation ('FAT MAX ' and steady state exercise protocols), body composition, cardio-metabolic and blood measures (serum glucose, insulin, leptin, adiponectin, glycerol, free fatty acids, total cholesterol, high [HDL-c] and low-density lipoprotein cholesterol [LDL-c], triglycerides, liver enzymes and bilirubin) were assessed at baseline, week 4 and 8. Following 8 weeks of dGTE+, maximal fat oxidation (MFO) significantly improved from 154.4 ± 20.6 to 224.6 ± 23.2 mg·min -1 ( p = 0.009), along with a 22.5% increase in the exercise intensity at which fat oxidation was deemed negligible (FAT MIN ; 67.6 ± 3.6%O 2peak , p = 0.003). Steady state exercise substrate utilisation also improved for dGTE+ only, with respiratory exchange ratio reducing from 0.94 ± 0.01 at week 4, to 0.89 ± 0.01 at week 8 ( p = 0.004). This corresponded with a significant increase in the contribution of fat to energy expenditure for dGTE+ from 21.0 ± 4.1% at week 4, to 34.6 ± 4.7% at week 8 ( p = 0.006). LDL-c was also lower (normalised fold change of -0.09 ± 0.06) for dGTE+ by week 8 ( p = 0.038). No other significant effects were found in any group. Eight weeks of dGTE+ improved MFO and substrate utilisation during exercise, and lowered LDL-c. However, body composition and cardio-metabolic markers in healthy, overweight individuals who maintained regular physical activity were largely unaffected by dGTE.

Preeclampsia remains a leading cause of maternal and perinatal morbidity and mortality. Accurate prediction of preeclampsia risk would enable more effective, risk-based prenatal care pathways. Current risk assessment algorithms depend on clinical risk factors largely unavailable for first-time pregnant women. Delivering accurate preeclampsia risk assessment to this cohort of women, therefore requires for novel biomarkers. Here, we evaluated the relevance of metabolite biomarker candidates for their selection into a prototype rapid, quantitative Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) based clinical screening assay. First, a library of targeted LC-MS/MS assays for metabolite biomarker candidates was developed, using a medium-throughput translational metabolomics workflow, to verify biomarker potential in the Screening-for-Pregnancy-Endpoints (SCOPE, European branch) study. A variable pre-selection step was followed by the development of multivariable prediction models for pre-defined clinical use cases, i.e., prediction of preterm preeclampsia risk and of any preeclampsia risk. Within a large set of metabolite biomarker candidates, we confirmed the potential of dilinoleoyl-glycerol and heptadecanoyl-2-hydroxy-sn-glycero-3-phosphocholine to effectively complement Placental Growth Factor, an established preeclampsia biomarker, for the prediction of preeclampsia risk in first-time pregnancies without overt risk factors. These metabolites will be considered for integration in a prototype rapid, quantitative LC-MS/MS assay, and subsequent validation in an independent cohort., Competing Interests: Leslie W. Brown and Robin Tuytten are employees of Metabolomic Diagnostics. Alison E Bond was an employee of Metabolomic Diagnostics at the time this work was conducted. Grégoire Thomas is the owner of SQU4RE, an independent Statistics and Data mining provider. This does not alter our adherence to PLOS ONE policies on sharing data and materials. Louise C. Kenny and Philip N. Baker are minority shareholders of Metabolomic Diagnostics. Leslie W. Brown, Robin Tuytten, Grégoire Thomas and Louise C. Kenny are named inventors on a Patent Application which discloses the use of specific proteins and metabolites to predict preeclampsia risk, and which is assigned to Metabolomic Diagnostics, i.e., “Methods of predicting pre term birth from preeclampsia using metabolic and protein biomarkers”, with publication number WO2019155075A1. This does not alter our adherence to PLOS ONE policies on sharing data and materials. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Objective: We investigated direct effects of a therapeutic growth hormone dose on lipolysis, glucose and amino acid metabolism., Methods: This crossover microdialysis trial involved six healthy male volunteers receiving single subcutaneous injections of both growth hormone (0.035 mg/kg) and placebo (0.9% sodium chloride). The investigation comprised three test days with standard diet. The first day served for adaptation, the second and third one for determining study data during 9 night hours with or without growth hormone. Abdominal subcutaneous microdialysate and blood were continuously collected and forwarded to a separate room next door where hourly taken samples were centrifuged and frozen until analysed., Results: Growth hormone achieved the peak serum level after 3 h followed by a plateau-like course for the next 6 h. Glycerol in microdialysate started to rise 2 h following growth hormone injection achieving significance compared to placebo after 9 h ( P <0.05). Serum glycerol increased 4 h after growth hormone administration achieving significance after 6 h ( P <0.05). Glucose and amino acid concentrations showed neither in microdialysate nor in serum significant differences between growth hormone and placebo. Serum values of insulin and C-peptide revealed no significant difference between growth hormone and placebo., Summary and Conclusion: As the result of a high single subcutaneous dose of GH, persistent lipolysis can be shown in continuously collected microdialysate and blood, but no indication for gluconeogenesis or protein anabolism., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) effectively lower plasma glucose (PG) concentration in patients with type 2 diabetes, but studies have suggested that circulating glucagon concentrations and endogenous glucose production (EGP) are increased by SGLT2i, possibly compromising their glucose-lowering ability. To tease out whether and how glucagon may influence the glucose-lowering effect of SGLT2 inhibition, we subjected 12 patients with type 2 diabetes to a randomized, placebo-controlled, double-blinded, crossover, double-dummy study comprising, on 4 separate days, a liquid mixed-meal test preceded by single-dose administration of either 1 ) placebo, 2 ) the SGLT2i empagliflozin (25 mg), 3 ) the glucagon receptor antagonist LY2409021 (300 mg), or 4 ) the combination empagliflozin + LY2409021. Empagliflozin and LY2409021 individually lowered fasting PG compared with placebo, and the combination further decreased fasting PG. Previous findings of increased glucagon concentrations and EGP during acute administration of SGLT2i were not replicated in this study. Empagliflozin reduced postprandial PG through increased urinary glucose excretion. LY2409021 reduced EGP significantly but gave rise to a paradoxical increase in postprandial PG excursion, which was annulled by empagliflozin during their combination (empagliflozin + LY2409021). In conclusion, our findings do not support that an SGLT2i-induced glucagonotropic effect is of importance for the glucose-lowering property of SGLT2 inhibition., (© 2020 by the American Diabetes Association.)

Tissues may respond differently to a particular stimulus if they have been previously exposed to that same stimulus. Here, we tested the hypothesis that a strong metabolic stimulus such as fasting may influence the hepatic response to a subsequent fast and thus elicit a memory effect. Overnight fasting in mice significantly increased plasma free fatty acids, glycerol, β-hydroxybutyrate, and liver triglycerides, and decreased plasma glucose, plasma triglycerides, and liver glycogen levels. In addition, fasting dramatically changed the liver transcriptome, upregulating genes involved in gluconeogenesis and in uptake, oxidation, storage, and mobilization of fatty acids, and downregulating genes involved in fatty acid synthesis, fatty acid elongation/desaturation, and cholesterol synthesis. Fasting also markedly impacted the liver metabolome, causing a decrease in the levels of numerous amino acids, glycolytic-intermediates, TCA cycle intermediates, and nucleotides. However, these fasting-induced changes were unaffected by two previous overnight fasts. Also, no significant effect was observed of prior fasting on glucose tolerance. Finally, analysis of the effect of fasting on the transcriptome in hepatocyte humanized mouse livers indicated modest similarity in gene regulation in mouse and human liver cells. In general, genes involved in metabolic pathways were upregulated or downregulated to a lesser extent in human liver cells than in mouse liver cells. In conclusion, we found that previous exposure to fasting in mice did not influence the hepatic response to a subsequent fast, arguing against the concept of metabolic memory in the liver. Our data provide a useful resource for the study of liver metabolism during fasting.

Scope: Inadequate intake of choline commonly leads to liver diseases. Methionine- and choline-deficient diets (MCDD) induce fatty liver in mice which is partly mediated by triglyceride (TG) lipolysis in white adipose tissues (WATs). Because Fatp4 knockdown has been shown to increase adipocyte lipolysis in vitro, here, the effects of MCDD on WAT lipolysis in aP2-Cre Fatp4-knockout (Fatp4 A-/- ) mice are determined., Methods and Results: Isolated WATs of Fatp4 A-/- mice exposed to MCD medium show an increase in lipolysis, and the strongest effect is noted on glycerol release from subcutaneous fat. Fatp4 A-/- mice fed with MCDD for 4 weeks show an increase in serum glycerol, TG, and leptin levels associated with the activation of hormone-sensitive lipase in subcutaneous fat. Chow-fed Fatp4 A-/- mice also show an increase in serum leptin and very-low-density lipoproteins as well as liver phosphatidylcholine and sphingomyelin levels. Both chow- and MCDD-fed Fatp4 A-/- mice show a decrease in serum ketone and WAT sphingomyelin levels which supports a metabolic shift to TG for subsequent WAT lipolysis CONCLUSIONS: Adipose Fatp4 deficiency leads to TG lipolysis and leptin release, which are exaggerated by MCDD. The data imply hyperlipidemia risk by a low dietary choline intake and gene mutations that increase adipose TG levels., (© 2020 The Authors. Molecular Nutrition & Food Research published by Wiley-VCH GmbH.)

Pregnancy toxemia is the most frequent metabolic disorder of ewes in late pregnancy. Although propylene glycol (PG) and glycerol (GLY) are common glucogenic supplements for treating pregnancy toxemia in ewes, the relative benefit of these 2 supplements is not entirely clear. Therefore, the objectives of the present study were to determine the changes during 24 h in key blood metabolites and insulin in response to PG or GLY drenching in prolific ewes. To this end, 36 multiparous late-pregnant Afec-Assaf ewes (∼132.4 d pregnant) bearing 2 to 4 fetuses, divided into 2 blocks (18 ewes in each block), with a blood β-hydroxybutyrate (BHB) concentration of 0.5 to 1.6 mmol/L were included. Ewes were divided into 3 groups (12 ewes each; 6 ewes in each experimental day), according to their BHB levels, expected litter size, body weight, and body condition score, and were drenched with the following: (1) control group (CTL), 55 mL of water; (2) PG, 106 mL of PG (100% PG, 448 calories); or (3) GLY, 108 mL of Koforin 80 (80% GL; 448 calories). Blood samples were taken before drenching and every hour after drenching for 24 h. Plasma concentration of glucose, BHB, nonesterified fatty acids, lactate, glycerol, and insulin were determined. Because there were no effects of treatments after 12 h in the first block, the data were analyzed for 12 h after drenching rather than 24 h. The plasma glucose concentration during the first 5 h after drenching was the highest in the GLY, BHB concentration was the lowest in the PG, and the nonesterified fatty acid levels were lower in the PG compared with the CTL ewes during the first 5 h after drenching. However, glucose concentration was higher in the PG ewes at 9, 11, and 12 h after drenching than in CTL or GLY ewes. The mean lactate concentration in plasma for 12 h was 2.5- and 1.9-fold higher in the PG compared with the CTL and GLY ewes, respectively, and except at 11 h after drenching, it was significantly higher at each time point. The insulin concentration was higher in the GLY than in both other groups at 2 to 5 h after drenching. These results suggest that during the first few hours after drenching the effect of PG was more effective in reducing the BHB concentration, whereas the GLY effect was more effective in enhancing glucose concentration. The increased concentration in lactate following PG treatment suggests that the PG contribution to gluconeogenesis is mediated through its metabolism to lactate. In contrast, the lack of an effect on lactate, and the faster increase in blood glucose in response to GLY suggest that GLY has a more advanced entry point to gluconeogenesis, which influences the immediate response in enhancing the glucose blood concentration., (Copyright © 2020 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Purpose: This study aimed to quantify net glycogen utilization in the vastus lateralis (VL) and gastrocnemius (G) of male (n = 11) and female (n = 10) recreationally active runners during three outdoor training sessions., Methods: After 2-d standardization of carbohydrate intakes (6 g·kg body mass per day), glycogen was assessed before and after 1) a 10-mile road run (10-mile) at lactate threshold, 2) 8 × 800-m track intervals (8 × 800 m) at velocity at V˙O2max, and 3) 3 × 10-min track intervals (3 × 10 min) at lactate turnpoint., Results: Resting glycogen concentration was lower in the G of female compared with males (P < 0.001) runners, although no sex differences were apparent in the VL (P = 0.40). Within the G and VL of male runners, net glycogen utilization differed between training sessions where 10 miles was greater than both track sessions (all comparisons, P < 0.05). In contrast, net glycogen utilization in female runners was not different between training sessions in either muscle (all comparisons, P > 0.05). Net glycogen utilization was greater in male than in female runners in both VL (P = 0.02) and G (P = 0.07) during the 10-mile road run. With the exception of male runners during the 3 × 10-min protocol (P = 0.28), greater absolute glycogen utilization was observed in the G versus the VL muscle in both male and female runners and during all training protocols (all comparisons, P < 0.05)., Conclusion: Data demonstrate that 1) prolonged steady-state running necessitates a greater glycogen requirement than shorter but higher-intensity track running sessions, 2) female participants display evidence of reduced resting muscle glycogen concentration and net muscle glycogen utilization when compared with male participants, and 3) net glycogen utilization is higher in the G muscle compared with the VL.

The ergogenic effect of caffeine is well established, although no investigations providing a high carbohydrate feeding strategy (pre-exercise meal=2 g/kg BM) co-ingested with caffeine exist for soccer. This investigation examines the effect of caffeine in addition to a pre-exercise carbohydrate meal and drink mid-way through a soccer simulation. Eight recreational soccer players completed an 85-minute soccer simulation followed by an exercise capacity test (Yo-yo Intermittent Endurance test level 2) on two occasions. Prior to exercise participants consumed a high carbohydrate meal, with placebo or 5 mg/kg BM -1 caffeine. No significant performance effect was identified (p=0.099) despite a 12.8% (109 m) improvement in exercise capacity following caffeine. Rates of carbohydrate and fat oxidation did not differ between conditions and nor were differences apparent for plasma glucose, fatty acids, glycerol, β-hydroxybutyrate (p>0.05). However, an increase in lactate was observed for caffeine (p=0.039). A significant condition effect on rating of perceived exertion was identified (p<0.001), with the overall mean for the protocol lowered to 11.7±0.9 au for caffeine compared to 12.8±1.3 au. Caffeine supplementation with a carbohydrate feeding strategy failed to affect metabolic and metabolite responses, although reductions in perception of exercise were observed. While a 12.8% increase in exercise capacity was noted the findings were not significant, possibly due to the small sample size., Competing Interests: The authors declare that they have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background The accurate and precise measurement of triglycerides is important due to the adverse effects associated with hypertriglyceridaemia. Most laboratory methods are based on enzymatic hydrolysis of triglycerides with measurement of the total glycerol. An elevated free glycerol concentration may result in overestimation of triglyceride concentrations. The removal of free glycerol by blanking may therefore be of clinical importance. The aim of this study was to compare the glycerol blanking and non-glycerol blanking triglyceride methods. Methods This was a method comparison study of 1518 samples from both in-patients and out-patients at Charlotte Maxeke Johannesburg Academic Hospital. Triglycerides were measured in each sample using both the blanking and the non-blanking methods. Analytical performance was assessed based on the National Cholesterol Education Program (NCEP) goals. Clinical impact was assessed according to the NCEP Adult Treatment Program III (ATP III) risk classification. Results The method median was significantly higher in the non-blanking compared to the blanking method (1.33 vs. 1.12 mmol/L, p < 0.0001) in all patients. The average bias was above the total allowable error of 15% across all groups. There was a significant change in NCEP ATP III risk classification, with fewer patients classified as normal (67.6% vs. 74.6%, p < 0.0001) with the non-blanking method compared to the blanking method. Conclusions There was a significant error when glycerol blanking for triglyceride determination was not performed. The non-blanking triglyceride method overestimates triglyceride concentrations. This does not only exceed analytical performance goals, but also impacts on patient categorisation and clinical decision making in all patients.

Brown adipose tissue generates heat via the mitochondrial uncoupling protein UCP1 to protect against obesity and hypothermia. Fas mutant MRL/lpr mice exhibit a significantly leaner phenotype compared to wild type MRL/MpJ mice. In this study, we evaluated the inflammatory cell population in the adipose tissue of MRL/lpr mice, which could potentially influence their lean phenotype. Furthermore, we compared beige fat activity between the MRL/MpJ and MRL/lpr mice. Fas mutation resulted in high body temperature, improved glucose tolerance, and decreased fat mass and adipocyte size. Fas mutation prevented high-fat diet-induced obesity and decreased the white adipose tissue M1:M2 ratio. When mice were fed a high-fat diet, UCP1, IL-4, IL-10, and tyrosine hydroxylase genes had significantly higher expression in Fas-mutant mice than in wild type mice. After a cold challenge, UCP1 expression and browning were also significantly higher in the Fas-mutant mice. In summary, Fas-mutant mice are resistant to high-fat diet-induced obesity due to increased IL-4 and IL-10 levels and the promotion of thermogenic protein activity and browning in their adipose tissues. STAT6 activation might contribute to M2 polarisation by increasing IL-4 and IL-10 levels while increases in M2 and tyrosine hydroxylase levels promote browning in response to Fas mutation.

Background: Triglyceride (TG) is a tri-ester composed of a glycerol and 3 fatty acids. Degradation of TG in adipose tissue is increased in the fasting state but inhibited in the postprandial state. Although insulin suppresses adipose TG degradation, patients with insulin resistance have high concentrations of insulin and free glycerol (FG) in the fasting state., Objective: We examined whether the fasting FG concentration reflects visceral obesity and insulin sensitivity in middle-aged Japanese men., Methods: We measured the fasting serum FG concentration in 72 males aged 30 to 50 years using a simple enzymatic method. The subjects were divided into tertiles according to their homeostasis model assessment of insulin resistance (HOMA-IR). Besides routine glucose- and lipid-related parameters, we determined insulin sensitivity as the rate of glucose disappearance in a 2-step hyperinsulinemic-euglycemic clamp and the abdominal visceral fat area (VFA) by magnetic resonance imaging., Results: The highest HOMA-IR tertile group had a higher fasting FG concentration than the middle- and lowest-tertile groups (0.077 ± 0.024 vs 0.063 ± 0.017 and 0.061 ± 0.016 mmol/L, P < .05 and P < .01). The FG concentration was positively correlated with VFA (rs = 0.36; P < .01) and the HOMA-IR score (rs = 0.26, P < .05) but negatively correlated with insulin sensitivity (rs = -0.26, P < .05). Multivariate regression analysis revealed that the FG concentration is independently associated with VFA and insulin sensitivity., Conclusion: The fasting FG concentration reflects VFA and insulin sensitivity in middle-aged Japanese men. The fasting FG concentration may be a potential surrogate marker of visceral obesity and insulin resistance in outpatients., (Copyright © 2020 National Lipid Association. Published by Elsevier Inc. All rights reserved.)

Purpose: AQP7, a water/glycerol transporting protein, regulates adipocyte glycerol efflux and influences lipid and glucose homeostasis. Altered AQP7 expression in adults leads to impaired glycerol dynamics, adipocyte hypertrophy, and a predisposition to obesity and diabetes. AQP7 gene promoter variants lead to impaired AQP7-mediated adipocyte glycerol efflux and adipocyte hypertrophy. To assess its possible involvement in childhood obesity and metabolic abnormalities, the AQP7 promoter was studied in order to identify possible mutations and/or polymorphisms in children., Methods: Genomic DNA was extracted from the blood of 61 lean children (BMI < 85%) (46 prepubertal and 15 pubertal) and 41 children with obesity (BMI > 95%) (22 prepubertal and 19 pubertal). The samples were sequenced for AQP7 promoter region - 2580 (2421) to - 1161 (3840) using Automated Sanger sequence analysis., Results: One novel mutation -2185 (T2816A) was found in an obese prepubertal child with low AQP7 mRNA expression, high levels of serum glycerol, and low serum insulin levels. The novel single nucleotide polymorphisms (SNPs) - 2291 (A2710G), - 2219 (C2782A), - 2091 (C2910A), and - 1932 (G3069A) were identified, together with the previously described SNP - 1884 (C3117T), rs3758268. The heterozygous state and the recessive allele of all four SNPs were related to a positive family history of diabetes mellitus type 2 (p = 0.001)., Conclusions: The novel mutation - 2185 (T2816A) might be associated with the lower gene expression of AQP7 and high levels of serum glycerol that possibly contribute to the obese phenotype. The heterozygous genotype of the four SNPs - 2291 (A2710G), - 2219 (C2782A), - 2091 (C2910A), and - 1884 (C3117T) in children may be related to a familial predisposition to diabetes mellitus type 2.

Background: Serum triglyceride concentrations are measured as total glycerides content in many Western countries. In Japan, glycerol-blanked triglycerides (TG-GB) are measured to identify postprandial hypertriglyceridaemia and to minimize the influence of glycerol formulation on serum triglyceride values. However, TG-GB measurements have not been standardized. Therefore, we developed an efficient quantification system for total glycerides and free glycerol that allows the calculation of TG-GB concentrations., Methods: We measured total glycerides and free glycerol in human serum by using gas chromatography-isotope dilution mass spectrometry and compared its performance to the reference method of the US Centers for Disease Control and Prevention (CDC)., Results: Our practical method of total glycerides and free glycerol quantification achieved excellent precision for both within-run and among-run coefficients of variation (<1.5% and <2.7%, respectively), with an average recovery of 99.8% for free glycerol. However, we noted an average %bias of -0.26% for total glycerides and -3.15% for free glycerol between our TG-GB method and the CDC reference method., Conclusions: This practical method of total glycerides and free glycerol quantification enables traceability assessment of TG-GB measurements. Differences between the output values of TG-GB and the CDC reference method might result from the differences in free glycerol values.

Scope: Abdominal obesity is one of the main modifiable risk factors of age-related cardiometabolic disease. Cardiometabolic disease risk and its associated high abdominal fat mass, cholesterol, and glucose concentrations can be reduced by a healthier lifestyle. Hence, the aim is to understand the relation between lifestyle-induced changes in body composition, and specifically abdominal fat, and accompanying changes in circulating metabolic biomarkers., Methods and Results: Data from the Growing Old Together (GOTO) study was used, which is a single arm lifestyle intervention in which 164 older adults (mean age 63 years, BMI 23-35 kg/m 2 ) changed their lifestyle during 13 weeks by 12.5% caloric restriction plus 12.5% increase in energy expenditure. It is shown here that levels of circulating metabolic biomarkers, even after adjustment for body mass index, specifically associate with abdominal fat mass. The applied lifestyle intervention mainly reduces abdominal fat mass (-2.6%, SD = 3.0) and this reduction, when adjusted for general weight loss, is highly associated with decreased circulating glycerol concentrations and increased HDL diameter., Conclusion: The lifestyle-induced reduction of abdominal fat mass is particularly associated, independent of body mass index or general weight loss, with decreased circulating glycerol concentrations and increased HDL diameter., (© 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We hypothesized that probiotic supplementation (PRO) increases the absorption and oxidation of orally ingested maltodextrin during 2 h endurance cycling, thereby sparing muscle glycogen for a subsequent time trial (simulating a road race). Measurements were made of lipid and carbohydrate oxidation, plasma metabolites and insulin, gastrointestinal (GI) permeability, and subjective symptoms of discomfort. Seven male cyclists were randomized to PRO (bacterial composition given in methods) or placebo for 4 wk, separated by a 14-day washout period. After each period, cyclists consumed a 10% maltodextrin solution (initial 8 mL/kg bolus and 2 mL/kg every 15 min) while exercising for 2 h at 55% maximal aerobic power output, followed by a 100-kJ time trial. PRO resulted in small increases in peak oxidation rates of the ingested maltodextrin (0.84 ± 0.10 vs. 0.77 ± 0.09 g/min; P = 0.016) and mean total carbohydrate oxidation (2.20 ± 0.25 vs. 1.87 ± 0.39 g/min; P = 0.038), whereas fat oxidation was reduced (0.40 ± 0.11 vs. 0.55 ± 0.10 g/min; P = 0.021). During PRO, small but significant increases were seen in glucose absorption, plasma glucose, and insulin concentration and decreases in nonesterified fatty acid and glycerol. Differences between markers of GI damage and permeability and time-trial performance were not significant ( P > 0.05). In contrast to the hypothesis, PRO led to minimal increases in absorption and oxidation of the ingested maltodextrin and small reductions in fat oxidation, whereas having no effect on subsequent time-trial performance.

The aim of this study was to investigate the circulatory, respiratory, and metabolic effects of induced hypercapnia via added respiratory dead space (ARDS) during moderate-intensity swimming in recreational swimmers. A mixed-sex sample of 22 individuals was divided into homogeneous experimental (E) and control (C) groups controlled for maximal oxygen uptake (VO 2 max). The intervention involved 50 min of front crawl swimming performed at 60% VO 2 max twice weekly for 6 consecutive weeks. ARDS was induced via tube breathing (1000 ml) in group E. An incremental exercise test was administered pre- and post-intervention to assess cardiorespiratory fitness (CRF) by measuring VO 2 max, carbon dioxide volume, respiratory minute ventilation, respiratory exchange ratio (RER), and heart rate at 50, 100, 150, 200 W and at maximal workload. Body mass index (BMI), fat mass (FM), and fat-free mass (FFM) were also measured. The mean difference in glycerol concentration (ΔGLY) was assessed after the first and last swimming session. No significant between-group differences were observed at post-intervention. No within-group differences were observed at post-intervention except for RER which increased in group E at maximal workload. A 6-week swimming intervention with ARDS did not enhance CRF. The RER increase in group E is not indicative of a substrate shift towards increased lipid utilization. No change in ΔGLY is evident of a lack of enhanced triglyceride hydrolyzation that was also confirmed by similar pre- and post-intervention BMI, FM, and FMM., (© Journal of Sports Science and Medicine.)

Background: Thermogenic fitness drink formulas (TFD) have been shown to increase energy expenditure and markers of lipid metabolism. The purpose of the current study was to compare TFD formulas containing different caffeine concentrations versus a placebo drink on energy expenditure and lipid metabolism at rest and during exercise., Methods: Thirty-two recreationally active participants (22.9 ± 0.7 y, 167.1 ± 1.4 cm, 68.8 ± 2.0 kg, 24.0 ± 1.2% fat) who were regular caffeine consumers, participated in this randomized, double-blind, crossover design study. Participants reported to the laboratory on three occasions, each of which required consumption of either a TFD containing 140 mg or 100 mg of caffeine or a placebo. Baseline measurements of resting energy expenditure (REE) and resting fat oxidation (RFO) were assessed using indirect calorimetry as well as measurements of serum glycerol concentration. Measurements were repeated at 30, 60, 90 min post-ingestion. Following resting measures, participants completed a graded exercise test to determine maximal oxygen uptake (V̇O 2max ), maximal fat oxidation (MFO) and the exercise intensity that elicits MFO (Fat max ), and total energy expenditure (EE)., Results: A significant interaction was shown for REE (p < 0.01) and RFO (p < 0.01). Area under the curve analysis showed an increased REE for the 140 mg compared to the 100 mg formula (p = 0.02) and placebo (p < 0.01) and an increased REE for the 100 mg formula compared to placebo (p = 0.02). RFO significantly decreased for caffeinated formulas at 30 min post ingestion compared to placebo and baseline (p < 0.01) and significantly increased for the 140 mg formula at 60 min post-ingestion (p = 0.03). A main effect was shown for serum glycerol concentrations over time (p < 0.01). No significant differences were shown for V̇O 2max (p = 0.12), Fat max (p = 0.22), and MFO (p = 0.05), and EE (p = 0.08) across drinks., Conclusions: Our results suggest that TFD formulas containing 100 and 140 mg of caffeine are effective in increasing REE and that a 40 mg of caffeine difference between the tested formulas may impact REE and RFO in healthy individuals within 60 min of ingestion.

With the increasing prevalence of obesity in women of reproductive age there is a need to understand the ramifications of this on offspring. The purpose of this study is to investigate the programming effects of maternal obesity during preconception and the preconception/gestational period on adiposity and adipose tissue inflammation in offspring using an animal model. Adult female C57Bl/6J mice were assigned either normal diet, high fat diet (HFD) prior to pregnancy, or HFD prior to and through pregnancy. Some offspring were maintained on normal diet while others started HFD later in life. Offspring were assessed for body composition and metabolic responses. Lipid storing tissues were evaluated for expansion and inflammation. Male offspring from the preconception group had the greatest weight gain, most subcutaneous adipose tissue, and largest liver mass when introduced to postnatal HFD. Male offspring of the preconception/gestation group had worsened glucose tolerance and an increase in resident (CD11c - ) adipose tissue macrophages (ATMs) when exposed to postnatal HFD. Female offspring had no significant difference in any parameter between the diet treatment groups. In conclusion, this study demonstrates that prenatal and pregnancy windows have independent programming effects on offspring. Preconception exposure affects body composition and adiposity while gestation exposure affects metabolism and tissue immune cell phenotypes.

Urbanization influences food quality and availability for many wild species, but our knowledge of the consequences urbanization has on the nutritional physiology of these animals is currently limited. To fill this gap, we captured House Sparrows (Passer domesticus) from rural and urban environments and hypothesized that increased access to human refuse in urban areas may significantly alter the gut microbiome and nutritional physiology of Sparrows. While there were no significant differences in circulating triglycerides or free glycerol concentrations between populations, urban birds had significantly greater blood glucose concentrations, which suggests greater circulating glucagon concentrations, accessibility to carbohydrates, and/or higher rates of gluconeogenesis in an urban setting. Rural birds had significantly more plasma uric acid, suggesting that they may metabolize more proteins or experience lower inflammation than urban birds. Rural birds also had significantly higher liver free glycerol concentrations, indicating that they metabolize more fat than urban birds. There were no significant differences in the relative abundance of gut microbial taxa at the phyla level between the two populations, but linear discriminant analysis effect size (LEfSe) showed that urban House Sparrows were more enriched with class- and order-level microbes from the phylum Proteobacteria, which are implicated in several mammalian intestinal and extra-intestinal diseases. These findings demonstrate that urbanization significantly alters the nutritional physiology and the composition of the gut microbiome of House Sparrows., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Air pollution exposure has been shown to increase the risk of obesity and metabolic dysfunction in animal models and human studies. However, the metabolic pathways altered by air pollution exposure are unclear, especially in adolescents and young adults who are at a critical period in the development of cardio-metabolic diseases., Objectives: The aim of this study was to examine the associations between air pollution exposure and indices of fatty acid and amino acid metabolism., Methods: A total of 173 young adults (18-23 years) from eight Children's Health Study (CHS) Southern California communities were examined from 2014 to 2018. Near-roadway air pollution (NRAP) exposure (freeway and non-freeway) and regional air pollution exposure (nitrogen dioxide, ozone and particulate matter) during one year before the study visit were estimated based on participants' residential addresses. Serum concentrations of 64 targeted metabolites including amino acids, acylcarnitines, non-esterified fatty acid (NEFA) and glycerol were measured in fasting serum samples. Principal component analysis of metabolites was performed to identify metabolite clusters that represent key metabolic pathways. Mixed effects models were used to analyze the associations of air pollution exposure with metabolomic principal component (PC) scores and individual metabolite concentrations adjusting for potential confounders., Results: Higher lagged one-year averaged non-freeway NRAP exposure was associated with higher concentrations of NEFA oxidation byproducts and higher NEFA-related PC score (all p's ≤ 0.038). The effect sizes were larger among obese individuals (interaction p = 0.047). Among females, higher freeway NRAP exposure was also associated with a higher NEFA-related PC score (p = 0.042). Among all participants, higher freeway NRAP exposure was associated with a lower PC score for lower concentrations of short- and median-chain acylcarnitines (p = 0.044)., Conclusions: Results of this study indicate that NRAP exposure is associated with altered fatty acid metabolism, which could contribute to the metabolic perturbation in obese youth., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Monoacylglycerol lipase (MGL) is the rate-limiting enzyme in the degradation of monoacylglycerols. To examine the role of MGL in hepatic steatosis, WT and MGL KO (MGL -/- ) mice were challenged with a Western diet (WD) over 12 weeks. Lipid metabolism, inflammation, and fibrosis were assessed by serum biochemistry, histology, and gene-expression profiling of liver and adipose depots. Intestinal fat absorption was measured by gas chromatography. Primary adipocyte and 3T3-L1 cells were analyzed by flow cytometry and Western blot. Human hepatocytes were treated with MGL inhibitor JZL184. The absence of MGL protected mice from hepatic steatosis by repressing key lipogenic enzymes in liver (Srebp1c, Pparγ2, and diacylglycerol O -acyltransferase 1), while promoting FA oxidation. Liver inflammation was diminished in MGL -/- mice fed a WD, as evidenced by diminished epidermal growth factor-like module-containing mucin-like hormone receptor-like 1 (F4/80) staining and C-C motif chemokine ligand 2 gene expression, whereas fibrosis remained unchanged. Absence of MGL promoted fat storage in gonadal white adipose tissue (gWAT) with increased lipogenesis and unchanged lipolysis, diminished inflammation in gWAT, and subcutaneous AT. Intestinal fat malabsorption prevented ectopic lipid accumulation in livers of MGL -/- mice fed a WD. In vitro experiments demonstrated increased adipocyte size/lipid content driven by PPARγ. In conclusion, our data uncover that MGL deletion improves some aspects of nonalcoholic fatty liver disease by promoting lipid storage in gWAT and fat malabsorption., (Copyright © 2019 Tardelli et al.)

Background: Low-birth-weight (LBWT) neonates grow at a slower rate than their normal-birth-weight (NBWT) counterparts and may develop hypoglycemia postnatally., Objective: We investigated whether dietary lipid supplementation would enhance growth and improve glucose production in LBWT neonatal pigs., Methods: Twelve 3-d-old NBWT (1.606 kg) crossbred pigs were matched to 12 LBWT (1.260 kg) same-sex littermates. At 6 d of age, 6 pigs in each group were fed a low-energy (LE) or a high-energy (HE) isonitrogenous formula containing 5.2% and 7.3% fat, respectively. Body composition was assessed using dual-energy X-ray absorptiometry; plasma glucose and glycerol kinetics were assessed using stable isotope tracers. After killing, weights of skeletal muscles and visceral organs were measured. Data were analyzed by ANOVA for a 2 × 2 factorial design; temporal effects were investigated using repeated-measures analysis., Results: Lipid supplementation did not affect body weight of LBWT or NBWT pigs. However, liver and longissimus dorsi weights as a percentage of body weight were greater for pigs fed an HE diet than for those fed an LE diet (4.3% compared with 3.4% and 1.5% compared with 1.2%, respectively) but remained less for LBWT than for NBWT pigs (3.8% compared with 3.9% and 1.3% compared with 1.5%, respectively) (P < 0.05). In addition, hepatic fat content increased (7.9 compared with 2.6 g) in pigs fed the HE compared with those fed the LE formula (P < 0.05). Lipid supplementation did not influence plasma glucose concentration which remained lower in the LBWT than in the NBWT group (4.1 compared with 4.5 mmol/L) (P < 0.05)., Conclusions: Our data suggest that lipid supplementation modestly improved growth of skeletal muscle and the liver but did not affect glucose homeostasis in all groups, and glucose concentration remained lower in LBWT than in NBWT pigs. These data suggest that the previously reported hyperglycemic effect of lipid supplementation may depend on the route of administration or age of the neonatal pig., (Copyright © American Society for Nutrition 2019.)

Background & Aims: Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) induce substantial weight loss and improve glycemic control in patients with type 2 diabetes, but it is not clear whether these occur via the same mechanisms. We compared absorption rates of glucose and protein, as well as profiles of gastro-entero-pancreatic hormones, in patients who had undergone SG or RYGB vs controls., Methods: We performed a cross-sectional study of 12 patients who had undergone sleeve gastrectomy, 12 patients who had undergone RYGB, and 12 individuals who had undergone neither surgery (controls), all in Denmark. Study participants were matched for body mass index, age, sex, and postoperative weight loss, and all had stable weights. They received continuous infusions of stable isotopes of glucose, glycerol, phenylalanine, tyrosine, and urea before and during a mixed meal containing labeled glucose and intrinsically phenylalanine-labeled caseinate. Blood samples were collected for 6 hours, at 10- to 60-minute intervals, and analyzed., Results: The systemic appearance of ingested glucose was faster after RYGB and SG vs controls; the peak glucose appearance rate was 64% higher after RYGB, and 23% higher after SG (both P < .05); the peak phenylalanine appearance rate from ingested casein was 118% higher after RYGB (P < .01), but similar between patients who had undergone SG and controls. Larger, but more transient increases in levels of plasma glucose and amino acids were accompanied by higher secretion of insulin, glucagon-like peptide 1, peptide YY, and cholecystokinin after RYGB, whereas levels of ghrelin were lower after SG, compared with RYGB and controls. Total 6-hour oral recovery of ingested glucose and protein was comparable among groups., Conclusions: Postprandial glucose and protein absorption and gastro-entero-pancreatic hormone secretions differ after SG and RYGB. RYGB was characterized by accelerated absorption of glucose and amino acids, whereas protein metabolism after SG did not differ significantly from controls, suggesting that different mechanisms explain improved glycemic control and weight loss after these surgical procedures. ClinicalTrials.gov ID NCT03046186., (Copyright © 2019 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Lipolysis is primarily controlled by the stepwise action of hormone-sensitive lipase (HSL) and monoglyceride lipase (MGL) to release free fatty acids and glycerol. A high level of circulating free fatty acids is well-known to mediate insulin resistance. Thus, the need to discover lipase inhibitors against both enzyme systems remains urgent. Agrochemicals are tightly regulated chemicals and therefore are potential source of new medicinal agents. Accordingly, we implemented a computational workflow to search for new lipase inhibitory leads by virtually screening commercial agrochemicals against HSL and MGL employing binding pharmacophores and docking experiments. Ten agrochemicals were identified as potential lipase inhibitors, out of which quinclorac, a safe herbicide, achieved high-ranking score. Subsequent in vitro evaluation against rat epididymal lipase activity showed quinclorac to exhibit nanomolar anti-lipase IC 50 . Subsequent in vivo testing showed quinclorac to significantly decrease blood glycerol levels after acute exposure (150 mg/kg) and multiple dosing (50 or 25 mg/kg) (p < 0.05)., (© 2018 John Wiley & Sons A/S.)

Purpose : Inconsistent results among studies examining the effects of caffeine on exercise performance are potentially due to interindividual variability in biological responses to caffeine ingestion. The aims, therefore, of the present study were to identify high and low caffeine responders and compare the influence of caffeine on exercise performance and biological responses between groups during a simulated soccer-game protocol on treadmill. Methods : Well-trained soccer players were distinguished as high (n = 11) and low (n = 9) caffeine responders based on resting blood pressure, plasma glycerol, nonesterified fatty acid, and epinephrine responses to caffeine. Participants underwent 2 simulated soccer-game protocols on a treadmill after caffeine (6 mg·kg -1 ) or placebo ingestion. Exercise performance and several biological responses were evaluated. Results : Exercise performance did not differ between the high and low responders to caffeine ( P  > .05). However, time to fatigue (high, caffeine: 797 [201] s vs placebo: 487 [258] s; low, caffeine: 625 [357] s vs placebo 447 [198] s) and countermovement jump (high, caffeine: 42.1 [5.5] cm vs placebo: 40.5 [5.7] cm; low, caffeine: 41.0 [3.8] cm vs placebo: 38.8 [4.6] cm) improved with caffeine relative to placebo ( P  < .001). Rating of perceived exertion was lower ( P  < .001) in high (13.4 [2.3]) than in low responders (14.3 [2.4]) with caffeine ingestion. Conclusions : Caffeine improved aerobic endurance and neuromuscular performance in well-trained soccer players regardless of their responsiveness to caffeine at rest. Since no changes in substrate utilization were found with caffeine supplementation, performance improvements could be attributed to positive effects on the central nervous system and/or neuromuscular function, although the precise mechanism remains unclear.

The viscosity of biofluids can be used to acquire meaningful medical information on the conditions of a patient but has seldom been utilized in clinical practices owing to cumbersome measurement procedures and the need for large sample volumes. We present a colorimetric method to measure the viscosity of blood plasma using a paper-based viscometer developed in this study specifically for clinical diagnosis. The proposed analytical device consists of multilayered papers with fluid-loading, -mixing, and -measuring regions, and it can be fabricated readily in a simple manner using three-layered paper channels and tape. Moreover, the colorimetric analysis enables viscosity estimations by analyzing a single optical image. To validate the device performance, we measured the viscosities of fluids such as glycerin aqueous solutions, bovine-serum-albumin solution, dimethyl sulfoxide, and blood plasma. We found that the measured viscosities were in good agreement with the reference values. Finally, we developed a simple smartphone application for the viscosity measurements that helped enhance the convenience and utility of the paper-based viscometer while maintaining the measurement accuracy.

Context: Primary dysregulation of adipose tissue lipolysis caused by genetic variation and independent of insulin resistance could explain unhealthy body fat distribution and its metabolic consequences., Objective: To analyze common single nucleotide polymorphisms (SNPs) in 48 lipolysis-, but not insulin-signaling-related genes, to form polygenic risk scores of lipolysis-associated SNPs, and to investigate their effects on body fat distribution, glycemia, insulin sensitivity, insulin secretion, and proinsulin conversion., Study Design, Participants, and Methods: SNP array, anthropometric, and metabolic data were available from up to 2789 participants without diabetes of the Tübingen Family study of type 2 diabetes characterized by oral glucose tolerance tests. In a subgroup (n = 942), magnetic resonance measurements of body fat stores were available., Results: We identified insulin-sensitivity-independent nominal associations (P < 0.05) of SNPs in 10 genes with plasma free fatty acids (FFAs), in 7 genes with plasma glycerol and in 6 genes with both, plasma FFAs and glycerol. A score formed of the latter SNPs (in ADCY4, CIDEA, GNAS, PDE8B, PRKAA1, PRKAG2) was associated with plasma FFA and glycerol measurements (1.4*10-9 ≤ P ≤ 1.2*10-5), visceral adipose tissue mass (P = 0.0326), and proinsulin conversion (P ≤ 0.0272). The more lipolysis-increasing alleles a subject had, the lower was the visceral fat mass and the lower the proinsulin conversion., Conclusions: We found evidence for a genetic basis of adipose tissue lipolysis resulting from common SNPs in CIDEA, AMP-activated protein kinase subunits, and cAMP signaling components. A genetic score of lipolysis-increasing alleles determined lower visceral fat mass and lower proinsulin conversion., (Copyright © 2019 Endocrine Society.)

Low temperature influences multiple physiological processes in fish. To explore the adaptability of the large yellow croaker (Larimichthys crocea) to low temperature, the concentrations of glycerol, blood urea nitrogen (BUN), and triglycerides (TG) in plasma, as well as the expression levels of metabolism-related genes aqp7 and aqp10, were measured after exposure to low temperature stress and during subsequent rewarming. In addition, tissue samples from the intestine and liver were histologically analyzed. We found that the concentrations of plasma glycerol, BUN, and TG, decreased under low temperature stress, suggesting the metabolism of fat and protein slowed at low temperature. The expression levels of aqp7 and aqp10 mRNA were also downregulated under exposure to low temperature. Interestingly, above plasma indices and gene expression returned to basic levels within 24 h after rewarming. Furthermore, the liver and the intestine were damaged under continuous low temperature stress, whereas they were repaired upon rewarming. From the above results, we concluded that aqp7 and aqp10 genes were sensitive to low temperature, and that the decrease in their expression levels at low temperature might reduce energy consumption by L. crocea. However, the adaptation to low temperature was limited because the key metabolic tissues were damaged under continuous exposure to low temperature. Interestingly, the metabolism of L. crocea was basically back to normal within 24 h of rewarming, showing that it has high capacity of self-recovery.

Background: Spinning exercise is one of the most popular types of exercise in fitness industry. Its effects on the post exercise metabolism compared to the isocaloric cyclic endurance exercise are not fully understood. The aim of the present study was to compare the effects of isocaloric (299.1±10.8 kcal) spinning vs. endurance exercise on fat and carbohydrate utilization, glucose, lactate, glycerol and NEFA blood concentration during exercise and recovery., Methods: Six recreationally active males (age: 23.5±0.71) were tested in two conditions: 1) 30-min spinning; 2) isocaloric continuous exercise. Each trial was followed by a 3-h recovery. Rates of carbohydrate and fat oxidation, the blood glucose, lactate, glycerol and NEFA concentration were assessed at rest, during exercise and recovery., Results: Spinning induced significantly higher fat and lower carbohydrate oxidation rate during a recovery period in comparison to isocaloric endurance exercise trial. Spinning induced almost six-fold higher increase in lipid to carbohydrate oxidation rate ratio at the beginning of second hour of postexercise period in comparison to constant intensity trial and reached similar values at 3 hours after exercise. Blood lactate was higher (P<0.01) at the end of exercise in spinning than continuous exercise (8.57±0.9 vs. 0.72±0.1 mmol·L-1), but became similar at the 60 min of recovery., Conclusions: These data indicate that spinning induces higher metabolic responses during recovery period, and most effectively shifts the pattern of substrate use toward lipids vs. isocaloric endurance exercise.

Context: Pro-inflammatory cytokine-stimulated lipolysis is one of the mechanisms underlying the pathogenesis of type 2 diabetes. However, whether it plays a role in the pathogenesis of post-pancreatitis diabetes mellitus (PPDM) remains unknown., Objective: To investigate the associations between markers of lipid metabolism and pro-inflammatory cytokines in individuals after acute pancreatitis (AP) in general, and in individuals with abnormal glucose metabolism (AGM) following AP in particular., Methods: Fasting blood samples were collected to measure markers of lipid metabolism (apolipoprotein-B, cholesterol, free fatty acids (FFA), glycerol, high and low-density lipoproteins, triglycerides) and cytokines (interleukin (IL)-6, monocyte chemoattractant protein (MCP)-1, and tumour necrosis factor (TNF) α). Linear regression analysis was conducted. Four statistical models were used to adjust for patient- and pancreatitis-related characteristics., Results: A total of 83 patients were recruited. IL-6 was significantly associated with glycerol in all models (p < .05), with glycerol levels increasing by 106% in individuals with AGM after AP (p <.05) compared to a 30.3% increase in individuals with normal glucose metabolism (NGM) (p >.05). TNFα was significantly associated with FFA (p = .015) in individuals with AGM after AP in the most adjusted model, with FFA levels increasing by 314% in these individuals compared to a 162% decrease in individuals with NGM after AP (p >.05)., Conclusions: Lipolysis appears to be an important pathogenetic mechanism in glucose derangements after diseases of the exocrine pancreas. IL-6 and TNFα are the driving forces behind lipolysis in individuals with AGM after AP. Modulation of lipolysis may be a promising therapeutic modality.

The aim of the present study was to investigate if peak fat oxidation rate (PFO) is related to Ironman performance in female athletes. Thirty-six female Ironman athletes (age: 34±1 yrs, [21-45 yrs.] SEM [Range]) with a BMI of 22.1±2.0 kg/m 2 [18.8-28.4 kg/m 2 ], a body fat percentage of 24.8±1.0% [9.0-37.0%] and a V̇O 2 peak of 53.0±1.3 ml/min/kg [36.5-70.5 ml/min/kg] were tested in the laboratory prior to the Ironman Copenhagen 2017. Race time ranged from 9:17:07 to 15:23:48 with mean race time being 11:57:26 h:min:s (717 min). By simple linear regression analyses we found associations between race time and P FO (r 2 =0.22, p<0.005), V̇O 2 peak (r 2 =0.65, p<0.0001) and the relative exercise intensity eliciting PFO (Fatmax) (r 2 =0.35, p=0.0001). Furthermore, associations were found between race time and body fat percentage (r 2 =0.44, p<0.0001) and age (r 2 =0.16, p<0.05). By means of multiple regression analysis, V̇O 2 peak was the only statistically significant variable explaining 64% of the variation in race time (adj. r 2 =0.64, p<0.005). In conclusion, these results demonstrate that PFO is not independently related to Ironman performance in a heterogeneous group of female athletes. Interestingly, V̇O 2 peak alone was able to predict 64% of the variation in Ironman race times., Competing Interests: The authors declare no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

Introduction: Glycerol phenylbutyrate (GPB) is approved in the US and EU for the chronic management of patients ≥2 months of age with urea cycle disorders (UCDs) who cannot be managed by dietary protein restriction and/or amino acid supplementation alone. GPB is a pre-prodrug, hydrolyzed by lipases to phenylbutyric acid (PBA) that upon absorption is beta-oxidized to the active nitrogen scavenger phenylacetic acid (PAA), which is conjugated to glutamine (PAGN) and excreted as urinary PAGN (UPAGN). Pharmacokinetics (PK) of GPB were examined to see if hydrolysis is impaired in very young patients who may lack lipase activity., Methods: Patients 2 months to <2 years of age with UCDs from two open label studies (n = 17, median age 10 months) predominantly on stable doses of nitrogen scavengers (n = 14) were switched to GPB. Primary assessments included traditional plasma PK analyses of PBA, PAA, and PAGN, using noncompartmental methods with WinNonlin™. UPAGN was collected periodically throughout the study up to 12 months., Results: PBA, PAA and PAGN rapidly appeared in plasma after GPB dosing, demonstrating evidence of GPB cleavage with subsequent PBA absorption. Median concentrations of PBA, PAA and PAGN did not increase over time and were similar to or lower than the values observed in older UCD patients. The median PAA/PAGN ratio was well below one over time, demonstrating that conjugation of PAA with glutamine to form PAGN did not reach saturation. Covariate analyses indicated that age did not influence the PK parameters, with body surface area (BSA) being the most significant covariate, reinforcing current BSA based dosing recommendations as seen in older patients., Conclusion: These observations demonstrate that UCD patients aged 2 months to <2 years have sufficient lipase activity to adequately convert the pre-prodrug GPB to PBA. PBA is then converted to its active moiety (PAA) providing successful nitrogen scavenging even in very young children., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

An ethanolic extract of Artemisia scoparia (SCO) has metabolically favorable effects on adipocyte development and function in vitro and in vivo. In diet-induced obese mice, SCO supplementation significantly reduced fasting glucose and insulin levels. Given the importance of adipocyte lipolysis in metabolic health, we hypothesized that SCO modulates lipolysis in vitro and in vivo. Free fatty acids and glycerol were measured in the sera of mice fed a high-fat diet with or without SCO supplementation. In cultured 3T3-L1 adipocytes, the effects of SCO on lipolysis were assessed by measuring glycerol and free fatty acid release. Microarray analysis, qPCR, and immunoblotting were used to assess gene expression and protein abundance. We found that SCO supplementation of a high-fat diet in mice substantially reduces circulating glycerol and free fatty acid levels, and we observed a cell-autonomous effect of SCO to significantly attenuate tumor necrosis factor-α (TNFα)-induced lipolysis in cultured adipocytes. Although several prolipolytic and antilipolytic genes were identified by microarray analysis of subcutaneous and visceral adipose tissue from SCO-fed mice, regulation of these genes did not consistently correlate with SCO's ability to reduce lipolytic metabolites in sera or cell culture media. However, in the presence of TNFα in cultured adipocytes, SCO induced antilipolytic changes in phosphorylation of hormone-sensitive lipase and perilipin. Together, these data suggest that the antilipolytic effects of SCO on adipose tissue play a role in the ability of this botanical extract to improve whole body metabolic parameters and support its use as a dietary supplement to promote metabolic resiliency.

Background: Emerging evidence indicates that individuals after an episode of acute pancreatitis (AP) are at an increased risk of developing metabolic derangements. While the link between general obesity and insulin resistance (IR) is well established, only a few studies have investigated the association between abdominal obesity and IR. The aim of this study was to investigate the associations between abdominal obesity and several indices of IR in individuals after an episode of AP., Methods: Patients were eligible for this cross-sectional study if they were previously admitted with a primary diagnosis of AP based on the recent international guidelines. Fasting venous bloods were collected to measure glucose, insulin, free fatty acids, glycerol, adiponectin (AD), omentin (OM), and vaspin (VAS). The IR indices - HOMA-IR, Adipo-IR, insulin*glycerol (IG) index, HOMA-AD, HOMA-OM, and HOMA-VAS were calculated. Modified Poisson regression was conducted, with statistical model adjusting for patient-, metabolic-, and pancreatitis-related risk factors. Areas under ROC curve were calculated and Bland-Altman plots were created., Results: Of the 92 individuals recruited, 41 had abdominal obesity. HOMA-IR, IG index, HOMA-OM, and HOMA-VAS were significantly associated with abdominal obesity, both in unadjusted and adjusted models. Area under ROC curves for HOMA-IR, IG index, HOMA-OM, and HOMA-VAS were 0.698, 0.695, 0.756, and 0.735, respectively. There was a good agreement between observed HOMA-IR values and values obtained from HOMA-OM (P = 0.733) and HOMA-VAS (P = 0.595)., Conclusion: Individuals with abdominal obesity after AP have a significantly higher IR, independent of diabetes and other covariates. Visceral adipose tissue specific adipokines, omentin and vaspin, hold promise for future clinical investigation of tissue-specific IR., (Copyright © 2018 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Obesity-related adipose tissue (AT) dysfunction, in particular subcutaneous AT (SCAT) lipolysis, is characterized by catecholamine resistance and impaired atrial natriuretic peptide (ANP) responsiveness. It remains unknown whether exercise training improves (non-)adrenergically mediated lipolysis in metabolically compromised conditions. We investigated the effects of local combined α-/β-adrenoceptor blockade on abdominal SCAT lipolysis in lean insulin sensitive (IS) ( n =10), obese IS ( n =10), and obese insulin resistant (IR) ( n =10) men. Obese men participated in a 12-week exercise training intervention to determine the effects on SCAT lipolysis. Abdominal SCAT extracellular glycerol concentration and blood flow (ATBF) were investigated using microdialysis, with/without locally combined α-/β-adrenoceptor blockade at rest, during low-intensity endurance-type exercise and post-exercise recovery. In obese IR men, microdialysis was repeated after exercise intervention. The exercise-induced increase in SCAT extracellular glycerol was more pronounced in obese IS compared with lean IS men, possibly resulting from lower ATBF in obese IS men. The exercise-induced increase in extracellular glycerol was blunted in obese IR compared with obese IS men, despite comparable local ATBF. Abdominal SCAT extracellular glycerol was markedly reduced (remaining ~60% of exercise-induced SCAT extracellular glycerol) following the local α-/β-adrenoceptor blockade in obese IS but not in IR men, suggesting reduced catecholamine-mediated lipolysis during exercise in obese IR men. Exercise training did not affect (non-)adrenergically mediated lipolysis in obese IR men. Our findings showed a major contribution of non-adrenergically-mediated lipolysis during exercise in male abdominal SCAT. Furthermore, catecholamine-mediated lipolysis may be blunted during exercise in obese IR men but could not be improved by exercise intervention, despite an improved metabolic profile and body composition., (© 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Cope's gray treefrog (Dryophytes chrysoscelis) is one of few freeze-tolerant frogs that mobilize glycerol as a cryoprotectant, yet cold and freezing-induced accumulation of this and other osmolytes has received little attention in this species. This study investigated the development of freeze tolerance in D. chrysoscelis, analyzing the response of the cryoprotectant system to cold acclimation, freezing, and thawing. Glycerol production was low and unresponsive to acclimation temperature, or duration of acclimation to 5 °C, except for one cold-acclimated frog that presented elevated glycerol in plasma, liver, and skeletal muscle. Curiously, glycerol concentration in skeletal muscle was higher than that of plasma and liver, in both warm- and cold-acclimated frogs, suggesting glycerol synthesis in muscle. Urea concentration in plasma doubled in response to cold acclimation but did not change during freezing. Freezing induced hepatic glycogen catabolism and an increase in glycerol and glucose in several tissues, although the mobilization dynamics differed between these cryoprotectants, possibly as a result of different transport mechanisms. Although hepatic glucose mobilization was of considerable magnitude, glucose accumulation in peripheral tissues was low and was surpassed by that of glycerol and urea. The muscle production of glycerol and the cold-induced accumulation of urea imply a role for skeletal muscle metabolism in the mobilization of cryoprotective solutes in D. chrysoscelis. The cryoprotectant system of D. chrysoscelis is complex, highly variable, and unique, with glycerol, glucose, and likely urea serving as cryoprotectants.

Purpose: New Zealand blackcurrant (NZBC) extract has previously been shown to increase fat oxidation during prolonged exercise, but this observation is limited to males. We examined whether NZBC intake also increases fat oxidation during prolonged exercise in females, and whether this was related to greater concentrations of circulating fatty acids., Methods: In a randomised, crossover, double-blind design, 16 endurance-trained females (age: 28 ± 8 years, BMI: 21.3 ± 2.1 kg·m -2 , VO 2max : 43.7 ± 1.1 ml·kg -1 ·min -1 ) ingested 600 mg·day -1 NZBC extract (CurraNZ ™ ) or placebo (600 mg·day -1 microcrystalline cellulose) for 7 days. On day 7, participants performed 120 min cycling at 65% VO 2max , using online expired air sampling with blood samples collected at baseline and at 15 min intervals throughout exercise for analysis of glucose, NEFA and glycerol., Results: NZBC extract increased mean fat oxidation by 27% during 120 min moderate-intensity cycling compared to placebo (P = 0.042), and mean carbohydrate oxidation tended to be lower (P = 0.063). Pre-exercise, plasma NEFA (P = 0.034) and glycerol (P = 0.051) concentrations were greater following NZBC intake, although there was no difference between conditions in the exercise-induced increase in plasma NEFA and glycerol concentrations (P > 0.05). Mean fat oxidation during exercise was moderately associated with pre-exercise plasma NEFA concentrations (r = 0.45, P = 0.016)., Conclusions: Intake of NZBC extract for 7 days elevated resting concentrations of plasma NEFA and glycerol, indicative of higher lipolytic rates, and this may underpin the observed increase in fat oxidation during prolonged cycling in endurance-trained females.