Postprandial Plasma Triacylglycerol Research Articles

Enhancing cardiometabolic health through physical activity and breakfast manipulations in children and adolescents: good for humans, good for the planet.

The human health benefits of cardiometabolic disease prevention can be accompanied by planetary co-benefits. Focusing efforts towards young people, including children and adolescents, is conducive to disease prevention. In the context of cardiometabolic disease prevention, this review paper critically summarises the available literature on the acute cardiometabolic responses to physical activity and breakfast manipulations among young people. Given the seriousness of global climate change, which will disproportionally affect our younger generations, this review paper offers new insights into the inherent interactions between child-adolescent behaviour and cardiometabolic health from an environmental sustainability perspective to aid climate change mitigation efforts, including exploring future research avenues. A growing evidence base suggests acute moderate- to high-intensity exercise bouts can attenuate postprandial plasma glucose, insulin and triacylglycerol concentrations for up to 24-48 h in young people. Whether accumulating physical activity throughout the day with short, frequent bouts promotes cardiometabolic risk marker attenuations is unclear. Breakfast consumption may enhance free-living physical activity and reduce glycaemic responses to subsequent meals for a possible additive impact. If repeated habitually, attenuations in these cardiometabolic risk factors would be conducive to disease prevention, reducing the greenhouse gas emissions associated with disease diagnosis and treatment. To progress current understanding with high public health and planetary relevance, research among samples of 'at risk' young people that span cellular-level responses to ecologically valid settings and address human and planetary health co-benefits is needed. Indeed, certain physical activity opportunities, such as active travel to school, offer important direct co-benefits to humans and planetary health.

Palmitic acid–rich oils with and without interesterification lower postprandial lipemia and increase atherogenic lipoproteins compared with a MUFA-rich oil: A randomized controlled trial

ABSTRACTBackgroundInteresterified (IE) fats are widely used in place of trans fats; however, little is known about their metabolism.ObjectivesTo test the impact of a commonly consumed IE compared with a non-IE equivalent fat on in vivo postprandial and in vitro lipid metabolism, compared with a reference oil [rapeseed oil (RO)].MethodsA double-blinded, 3-phase crossover, randomized controlled trial was performed in healthy adults (n = 20) aged 45–75 y. Postprandial plasma triacylglycerol and lipoprotein responses (including stable isotope tracing) to a test meal (50 g fat) were evaluated over 8 h. The test fats were IE 80:20 palm stearin/palm kernel fat, an identical non-IE fat, and RO (control). In vitro, mechanisms of digestion were explored using a dynamic gastric model (DGM).ResultsPlasma triacylglycerol 8-h incremental area under the curves were lower following non-IE compared with RO [–1.7 mmol/L⋅h (95% CI: –3.3, –0.0)], but there were no differences between IE and RO or IE and non-IE. LDL particles were smaller following IE and non-IE compared with RO (P = 0.005). Extra extra large, extra large, and large VLDL particle concentrations were higher following IE and non-IE compared with RO at 6–8 h (P < 0.05). No differences in the appearance of [13C]palmitic acid in plasma triacylglycerol were observed between IE and non-IE fats. DGM revealed differences in phase separation of the IE and non-IE meals and delayed release of SFAs compared with RO.ConclusionsInteresterification did not modify fat digestion, postprandial lipemia, or lipid metabolism measured by stable isotope and DGM analysis. Despite the lower lipemia following the SFA-rich fats, increased proatherogenic large triacylglycerol-rich lipoprotein remnant and small LDL particles following the SFA-rich fats relative to RO adds a new postprandial dimension to the mechanistic evidence linking SFAs to cardiovascular disease risk.

Cholesteryl Ester Transfer Protein Impairs Triglyceride Clearance via Androgen Receptor in Male Mice.

Elevated postprandial triacylglycerols (TAG) are an important risk factor for cardiovascular disease. Men have higher plasma TAG and impaired TAG clearance compared to women, which may contribute to sex differences in risk of cardiovascular disease. Understanding mechanisms of sex differences in TAG metabolism may yield novel therapeutic targets to prevent cardiovascular disease. Cholesteryl ester transfer protein (CETP) is a lipid shuttling protein known for its effects on high‐density lipoprotein (HDL) cholesterol levels. Although mice lack CETP, we previously demonstrated that transgenic CETP expression in female mice alters TAG metabolism. The impact of CETP on TAG metabolism in males, however, is not well understood. Here, we demonstrate that CETP expression increases plasma TAG in males, especially in very‐low density lipoprotein (VLDL), by impairing postprandial plasma TAG clearance compared to wild‐type (WT) males. Gonadal hormones were required for CETP to impair TAG clearance, suggesting a role for sex hormones for this effect. Testosterone replacement in the setting of gonadectomy was sufficient to restore the effect of CETP on TAG. Lastly, liver androgen receptor (AR) was required for CETP to increase plasma TAG. Thus, expression of CETP in males raises plasma TAG by impairing TAG clearance via testosterone signaling to AR. Further understanding of how CETP and androgen signaling impair TAG clearance may lead to novel approaches to reduce TAG and mitigate risk of cardiovascular disease.

The Effect of Fructose Feeding on Intestinal Triacylglycerol Production and De Novo Fatty Acid Synthesis in Humans.

A high fructose intake exacerbates postprandial plasma triacylglycerol (TAG) concentration, an independent risk factor for cardiovascular disease, although it is unclear whether this is due to increased production or impaired clearance of triacylglycerol (TAG)-rich lipoproteins. We determined the in vivo acute effect of fructose on postprandial intestinal and hepatic lipoprotein TAG kinetics and de novo lipogenesis (DNL). Five overweight men were studied twice, 4 weeks apart. They consumed hourly mixed-nutrient drinks that were high-fructose (30% energy) or low-fructose (<2% energy) for 11 h. Oral 2H2O was administered to measure fasting and postprandial DNL. Postprandial chylomicron (CM)-TAG and very low-density lipoprotein (VLDL)-TAG kinetics were measured with an intravenous bolus of [2H5]-glycerol. CM and VLDL were separated by their apolipoprotein B content using antibodies. Plasma TAG (p < 0.005) and VLDL-TAG (p = 0.003) were greater, and CM-TAG production rate (PR, p = 0.046) and CM-TAG fractional catabolic rate (FCR, p = 0.073) lower when high-fructose was consumed, with no differences in VLDL-TAG kinetics. Insulin was lower (p = 0.005) and apoB48 (p = 0.039), apoB100 (p = 0.013) and non-esterified fatty acids (NEFA) (p = 0.013) were higher after high-fructose. Postprandial hepatic fractional DNL was higher than intestinal fractional DNL with high-fructose (p = 0.043) and low-fructose (p = 0.043). Fructose consumption had no effect on the rate of intestinal or hepatic DNL. We provide the first measurement of the rate of intestinal DNL in humans. Lower CM-TAG PR and CM-TAG FCR with high-fructose consumption suggests lower clearance of CM, rather than elevated production, may contribute to elevated plasma TAG, possibly due to lower insulin-mediated stimulation of lipoprotein lipase.

No Difference in Lipemic Response or Endothelial Function Following Interesterified and Non-Interesterified Functionally Equivalent Fats: A Randomized Controlled Trial

Abstract Objectives Interesterified (IE) fats are now used as hard fats to replace harmful trans fats, however the cardiometabolic health impact of the most commonly consumed IE fat blends are unknown. The InterCardio study (NCT03438084) investigated the effect of the most commonly consumed IE spread versus functionally equivalent hard fats and a control oil, on postprandial lipemia (PPL) and acutely changing markers of endothelial function. Methods A four-armed, double blind, randomized controlled trial in healthy males and females (n = 50) aged 35–75 years compared sequential test meals (0 h; 897 kcal, 50 g fat, 16 g protein, 88 g carbohydrate, 5 h; 550 kcal, 30 g fat, 15 g protein, 39 g carbohydrate) on postprandial plasma triacylglycerol (TG) concentrations, endothelial function (flow mediated dilation (FMD)), plasma nitrite concentrations and NADPH oxidase activity. Test fats were: a commercially available IE spread, a functionally equivalent non-IE spread, spreadable butter (SB), and a high-MUFA oil (rapeseed oil) as control. Melt curve data for the spreadable fats showed similar solid fat content at 37°C (IE; 0.3%, non-IE; 0.4%, SB; 0%). Blood was collected at fasting and regular intervals up to 8 hrs, and FMD was measured at fasting, 4.5 hrs and 7.5 hrs. Results All 4 test fats increased TG levels postprandially, reaching peak concentrations at 6 hrs. There was no significant treatment or treatment x time effects on plasma TAG concentrations (P = 0.684), nor incremental areas under the curves up to 4 and 8 hrs; mean iAUC0–8 h (95% CI) were 5.4 mmol/L.h (4.3, 6.4) for IE spread, 5.7 mmol/L.h (4.3, 6.8) for non-IE spread, 5.5 mmol/L.h (4.0, 7.0) for SB and 5.9 mmol/L.h (4.3,6.8) for rapeseed oil. There were no significant treatment effects on endothelial function, while nitrite concentrations and NADPH oxidase activity reduced postprandially. Mean NAPDH oxidase activity following IE spread, non-IE spread, SB and rapeseed oil at 6 h were 322, 333, 270, and 268 respectively. Conclusions In the first study to investigate the acute effects of commercially relevant IE and non-IE spreads and SB, we report no adverse effect of IE fats on acutely changing cardiometabolic risk factors relative to a high-MUFA reference oil. The similar effects on endothelial function and postprandial lipemia is likely to be due to their similar solid fat content at body temperature. Funding Sources BBSRC.

Interesterification of a commonly consumed palm-based hard fat blend does not affect postprandial lipoprotein metabolism in healthy older adults

AbstractInteresterified (IE) fats are widely used to replace partially-hydrogenated fats as hard fats with functional and sensory properties needed for spreads/margarines, baked goods, and confectionary, while avoiding the health hazards of trans fats. Detailed mechanistic work to determine the metabolic effects of interesterification of commonly-consumed hard fats has not yet been done. Earlier studies using fats less commonly consumed have shown either neutral or a lowering effect on postprandial lipaemia. We investigated postprandial lipaemia, lipoprotein remodelling, and triacylglycerol-rich lipoprotein (TRL) fraction apolipoprotein concentrations following a common IE blend of palm oil/kernel fractions versus its non-IE counterpart, alongside a reference monounsaturated (MUFA) oil. A 3-armed, double blind, randomized controlled trial (clinicaltrials.gov NCT03191513) in healthy adults (n = 20; 10 men, 10 women) aged 45–75 y, assessed effects of single meals (897 kcal, 50 g fat, 16 g protein, 88 g carbohydrate) on postprandial plasma triacylglycerol (TAG) concentrations, lipoprotein profiles, and TRL fraction apolipoprotein B48 and TAG concentrations. Test fats were IE 80:20 palm stearin/palm kernel fat, the equivalent non-IE fat, and a high-MUFA reference oil (rapeseed oil, RO). Blood was collected at baseline and hourly for 8 h. Linear mixed modelling was performed, adjusting for treatment order and baseline values (ver. 24.0; SPSS Inc., Chicago, IL, USA). Total 8 h incremental area under the curves (iAUC) for plasma TAG concentrations were lower following IE and non-IE compared with RO (mean difference in iAUC: non-IE vs. RO -1.8 mmol/L.h (95% CI -3.3, -0.2); IE vs. RO -2.6 mmol/L.h (95% CI -5.3, 0.0)), but iAUCs for IE and non-IE were not significantly different. There were no differences between IE and non-IE for chylomicron fraction apoB48 concentrations nor TAG:apoB48 ratio. No differences were observed between IE and non-IE for lipoprotein (VLDL, HDL, LDL) particle size or sub-class particle concentrations. However, LDL particle diameters were reduced at 5 and 6 h following IE vs RO (P &lt; 0.05). XXL- (including chylomicron remnants and VLDL particles), XL- and L-VLDL particle concentrations (average diameters &gt; 75, 64, and 53.6 nm respectively) were higher following IE and non-IE vs. RO at 6 h (P &lt; 0.05) and 8 h postprandially (P &lt; 0.005–0.05). In conclusion, both IE and non-IE palmitic acid-rich fats generated a greater preponderance of pro-atherogenic large TRL remnant particles in the late postprandial phase relative to an oleic acid-rich oil. However, the process of interesterification did not modify postprandial TAG response or lipoprotein metabolism.

A single bout of resistance exercise improves postprandial lipid metabolism in overweight/obese men with prediabetes.

Prediabetes is associated with postprandial hypertriacylglycerolaemia. Resistance exercise acutely lowers postprandial plasma triacylglycerol (TG); however, the changes in lipid metabolism that mediate this reduction are poorly understood. The aim of this study was to identify the constitutive metabolic mechanisms underlying the changes in postprandial lipid metabolism after resistance exercise in obese men with prediabetes. We evaluated the effect of a single bout of whole-body resistance exercise (seven exercises, three sets, 10-12 repetitions at 80% of one-repetition maximum) on postprandial lipid metabolism in ten middle-aged (50 ± 9years), overweight/obese (BMI: 33 ± 3kg/m2), sedentary men with prediabetes (HbA1c >38 but <48mmol/mol [>5.7% but <6.5%]), or fasting plasma glucose >5.6mmol/l but <7.0mmol/l or 2h OGTT glucose >7.8mmol/l but <11.1mmol/l). We used a randomised, crossover design with a triple-tracer mixed meal test (ingested [(13C4)3]tripalmitin, i.v. [U-13C16]palmitate and [2H5]glycerol) to evaluate chylomicron-TG and total triacylglycerol-rich lipoprotein (TRL)-TG kinetics. We used adipose tissue and skeletal muscle biopsies to evaluate the expression of genes regulating lipolysis and lipid oxidation, skeletal muscle respirometry to evaluate oxidative capacity, and indirect calorimetry to assess whole-body lipid oxidation. The single bout of resistance exercise reduced the lipaemic response to a mixed meal in obese men with prediabetes without changing chylomicron-TG or TRL-TG fractional clearance rates. However, resistance exercise reduced endogenous and meal-derived fatty acid incorporation into chylomicron-TG and TRL-TG. Resistance exercise also increased whole-body lipid oxidation, skeletal muscle mitochondrial respiration, oxidative gene expression in skeletal muscle, and the expression of key lipolysis genes in adipose tissue. A single bout of resistance exercise improves postprandial lipid metabolism in obese men with prediabetes, which may mitigate the risk for cardiovascular disease and type 2 diabetes.

Lower Postprandial Lipemia After Palmitic Acid-rich Fats with and Without Interesterification Is Associated with Increased Atherogenic Lipoproteins versus a High MUFA Oil (OR19-03-19)

ObjectivesInteresterified (IE) fats are commonly used as hard fat alternatives to trans fats. However, their health effects are unknown. Postprandial lipemia is an independent risk factor for CVD; a prolonged postprandial lipemia may detrimentally impact lipoprotein remodelling. We compared the postprandial lipoprotein profiles of palmitic acid-rich IE and non-IE fats and an unsaturated control oil. MethodsA double blind, randomized controlled trial in healthy adults (n = 20) aged 45–75 years, assessed effects of single test meals (897 kcal, 50 g fat, 16 g protein, 88 g carbohydrate) on postprandial plasma triacylglycerol (TG) concentrations by colorimetric assay and lipoprotein profiles by NMR. Test fats were: a commonly consumed IE [80:20 palm stearin/palm kernel fat], the equivalent non-IE fat, and a control high-MUFA rich oil (canola oil, CO) as a reference point. Blood was collected at baseline, and hourly thereafter for 8h. Lipoprotein statistical analysis used linear mixed effect regression modelling (lme4 package on R). Metabolites were considered as response and treatment as predictor along with various covariates: time, period, baseline values, and subject (random effect), with post hoc adjustment for multiple comparisons. ResultsThere was a significant time x treatment interaction (P = 0.006) in change from baseline for plasma TG concentrations (Figure 1), with significant differences between the IE fat and CO and the non-IE fat and CO (both P = 0.001), but no difference between IE and non-IE fats. NMR analysis of lipoprotein (VLDL, HDL, LDL) particle size, composition and number, revealed an increase in particle and cholesterol concentrations following IE and non-IE fats versus the CO at T + 8h for the following lipoprotein fractions: chylomicron remnants and extremely large VLDL (non-IE vs CO P < 0.05; IE vs CO P < 0.001; Figure 2), and very large VLDL (non-IE vs CO P < 0.01; IE vs CO P < 0.005). ConclusionsInteresterification of a commonly consumed palm-based fat did not modify lipoprotein particle size or composition. Despite a reduction in postprandial lipemia, the generation of atherogenic TG-rich lipoprotein remnant particles in the late postprandial phase may in part explain the atherogenic potential of saturated rich fats compared with unsaturated rich fats. Funding SourcesBBSRC DRINC, UK. Supporting Tables, Images and/or Graphs▪▪

Prevalence of food addiction and its influencing factors among newly diagnosed type 2 diabetes mellitus patients in Xinjiang region of China

Objective To investigate the prevalence of food addiction among newly diagnosed type 2 diabetes mellitus (T2DM) patients in Xinjiang region and to analyze its influencing factors. Methods From January 2017 to December 2017, we selected 279 newly diagnosed T2DM patients in Endocrinology Outpatient Department of the First Affiliated Hospital of Xinjiang Medical University as subjects by convenience sampling. The Yale Food Addiction Scale was used to judge the food addiction of patients. All selected patients were divided into group of food addiction and group of non-food addiction based on results. We collected and compared the clinical data both groups, and used Spearman correlation to analyze the correlations between food addiction and clinical data, and used Logistic regression to analyze the influencing factors of food addiction. Results A total of 39 patients were judged as food addiction with 13.98% (39/279) for the proportion. In group of food addiction, the body mass index (BMI) , waistline, waistline/height, fasting blood glucose (FBG) , 2-hour postprandial plasma glucose (2 h-PG) , triacylglycerol and insulin resistance index were higher than those in group of non-food addiction, and the insulin secretion index was lower than that in control group, the differences were all statistically significant (P<0.05) . Spearman correlation analysis showed that food addiction had positive correlations with the sexes, BMI, waistline, waistline/height and FBG, and had a negative correlation with the ages (P<0.05) . Logistic regression analysis showed that the influencing factors of food addiction among newly diagnosed T2DM patients included sexes, ages and BMI (P<0.05) . Conclusions The proportion of food addiction is high among newly diagnosed T2DM patients in Xinjiang region of China which is related to sexes, ages and BMI. Medical staff should pay attention to the screening of food addiction and intervention for life style so as to prevent diabetes and other metabolism diseases. Key words: Diabetes mellitus, type 2; Newly diagnosed; Food addiction; Influencing factors

Apolipoprotein E (epsilon) genotype has a greater impact on apoB-48 than apoB-100 responses to dietary fat manipulation-insights from the SATgenε study.

To determine the contribution of intestinally and liver-derived lipoproteins to the postprandial plasma triacylglycerol (TAG) response in APOE3/E3 and E3/E4 individuals following chronic dietary fat manipulation. In sequential order, participants (n = 12 E3/E3, n = 11 E3/E4) followed low fat; high-fat, high-saturated fat (HSF); and HSF with 3.45 g/day docosahexaenoic acid (HSF-DHA) diets, each for 8 weeks. After each dietary period, an acute test meal with a macronutrient profile representative of the dietary intervention was consumed. Apolipoprotein (apo)B isoforms were determined in isolated TAG-rich lipoprotein fractions (Svedberg flotation rate (Sf ) > 400, Sf 60-400, and Sf 20-60) by specific ELISA. A genotype × meal/diet interaction for the Sf > 400 fraction apoB-48 response (p < 0.05) was observed, with higher concentrations reached after the low fat than HSF-DHA meal in E4 carriers. This finding was associated with a lower TAG content of the Sf > 400 particles. Fasting Sf 60-400 and 20-60 apoB-48 concentrations were also significantly higher in E4 carriers. No impact of genotype on the apoB-100 responses was evident. Our study revealed marked effects of dietary fat composition on the Sf > 400 apoB-48 response and particle TAG content in E4 carriers relative to the "wild-type" E3/E3 genotype, which suggest APOE genotype is a potential modulator of chylomicron particle synthesis.

Sex-Specific Differences in Hepatic Fat Oxidation and Synthesis May Explain the Higher Propensity for NAFLD in Men.

In most populations a greater proportion of men have hepatic steatosis than women. Sex-specific differences in hepatic dietary fatty acid (FA) metabolism have not been well characterized. We compared fasting and postprandial hepatic FA synthesis (de novo lipogenesis [DNL]) and oxidation in men and women. Fasting and postprandial hepatic FA metabolism was studied in 22 healthy men (n = 11) and women with similar age, body mass index, and liver fat content using metabolic substrates labeled with stable-isotope tracers ((2)H2O and [U(13)C]palmitate). Dietary FA oxidation was assessed by appearance of (13)C into plasma 3-hydroxybutyrate and breath CO2 as markers of liver and whole-body FA oxidation, respectively. Despite similar liver fat content, fasting and postprandial plasma triacylglycerol (TG) concentrations were significantly (P < .05) higher in men compared with women. The appearance of (13)C from dietary FA into plasma 3-hydroxybutyrate and breath CO2 was greater (P < .05) in women compared with men. Although the contribution of DNL into very low-density lipoprotein (VLDL)-TG was similar (∼ 10%) in the fasting state, there was a divergence in pattern over the course of the study, with men maintaining a higher contribution of DNL to VLDL-TG than women (P = .006 time x sex interaction). The combination of lower dietary FA oxidation and a prolonged increase in DNL observed in men may represent partitioning of FA into esterification and storage pathways within the liver, leading to greater VLDL-TG production, and predispose to the sex difference in hepatic steatosis.

Resistance Exercise Attenuates High-Fructose, High-Fat-Induced Postprandial Lipemia.

INTRODUCTIONMeals rich in both fructose and fat are commonly consumed by many Americans, especially young men, which can produce a significant postprandial lipemic response. Increasing evidence suggests that aerobic exercise can attenuate the postprandial increase in plasma triacylglycerols (TAGs) in response to a high-fat or a high-fructose meal. However, it is unknown if resistance exercise can dampen the postprandial lipemic response to a meal rich in both fructose and fat.METHODSEight apparently healthy men (Mean ± SEM; age = 27 ± 2 years) participated in a crossover study to examine the effects of acute resistance exercise on next-day postprandial lipemia resulting from a high-fructose, high-fat meal. Participants completed three separate two-day conditions in a random order: (1) EX-COMP: a full-body weightlifting workout with the provision of additional kilocalories to compensate for the estimated net energy cost of exercise on day 1, followed by the consumption of a high-fructose, high-fat liquid test meal the next morning (day 2) (~600 kcal) and the determination of the plasma glucose, lactate, insulin, and TAG responses during a six-hour postprandial period; (2) EX-DEF: same condition as EX-COMP but without exercise energy compensation on day 1; and (3) CON: no exercise control.RESULTSThe six-hour postprandial plasma insulin and lactate responses did not differ between conditions. However, the postprandial plasma TAG concentrations were 16.5% and 24.4% lower for EX-COMP (551.0 ± 80.5 mg/dL × 360 minutes) and EX-DEF (499.4 ± 73.5 mg/dL × 360 minutes), respectively, compared to CON (660.2 ± 95.0 mg/dL × 360 minutes) (P < 0.05).CONCLUSIONSA single resistance exercise bout, performed ~15 hours prior to a high-fructose, high-fat meal, attenuated the postprandial TAG response, as compared to a no-exercise control condition, in healthy, resistance-trained men.

Acute energy intake restriction, moderate intensity exercise and postprandial plasma triacylglycerol concentration in girls

This study compared the effect of an isoenergetic energy deficit, induced by mild energy-intake restriction or acute exercise, on postprandial triacylglycerol concentrations ([TAG]) in girls. Eleven healthy girls (mean(SD): age 12.1(0.6) years; body mass 42.1(5.8) kg; peak oxygen uptake ( V ̇ O 2 peak ) 47(6) mL kg −1 min −1 ) completed three, two-day conditions in a counterbalanced, crossover design. On day 1, participants rested (CON), restricted food energy intake by 1.47(0.18) MJ (ER) or walked at 60% V ̇ O 2 peak (EX; net energy expenditure 1.46(0.01) MJ). On day 2, capillary blood samples were taken in the fasted state and at pre-determined intervals throughout the 6.5 h postprandial period. A standardised breakfast was consumed immediately after the fasting sample and a standardised lunch at 4 h. Compared with CON, fasting [TAG] was lower after ER (95% confidence interval (95% CI) −0.22 to −0.01, effect size (ES) = 0.42) and EX (95% CI −0.38 to −0.19, ES = 1.33); EX was lower than ER (95% CI −0.30 to −0.03, ES = 0.66). Differences in postprandial [TAG] over time between conditions were moderate (ES = 0.50). The total area under the [TAG] versus time curve was lower after EX than CON (95% CI −2.89 to −0.86, ES = 0.80), with a small difference between ER and CON (95% CI −1.85 to 0.16, ES = 0.27) and EX and ER (95% CI −2.48 to 0.42, ES = 0.40). An exercise-induced energy deficit elicits a greater reduction in fasting and postprandial [TAG] in girls than an isoenergetic diet-induced energy deficit.

Effect of High-Intensity Intermittent Exercise on Postprandial Plasma Triacylglycerol in Sedentary Young Women

High-intensity intermittent exercise (HIIE) such as the 30-s Wingate test attenuates postprandial triacylglycerol (TG), however, the ability of shorter versions of HIIE to reduce postprandial TG is undetermined. Thus, the effect of 8-s sprinting bouts of HIIE on blood TG levels of 12 females after consumption of a high-fat meal (HFM) was examined. Twelve young, sedentary women (BMI 25.1 ± 2.3 kg/m²; age 21.3 ± 2.1 years) completed a maximal oxygen uptake test and then on different days underwent either an exercise or a no-exercise postprandial TG condition. Both conditions involved consuming a HFM after a 12-hr fast. The HFM, in milkshake form provided 4170 kJ (993 Kcal) of energy and 98 g fat. Order was counter-balanced. In the exercise condition participants completed 20-min of HIIE cycling consisting of repeated bouts of 8 s sprint cycling (100-115 rpm) and 12 s of active rest (easy pedaling) 14 hr before consuming the HFM. Blood samples were collected hourly after the HFM for 4 hr. Total postprandial TG was 13% lower, p = .004, in the exercise (5.84 ± 1.08 mmol L⁻¹ 4 h⁻¹) compared with the no-exercise condition (6.71 ± 1.63 mmol L⁻¹ 4 h⁻¹). In conclusion, HIIE significantly attenuated postprandial TG in sedentary young women.

Acute High-Intensity Interval Running Reduces Postprandial Lipemia in Boys

Acute moderate-intensity exercise reduces postprandial lipemia in boys. However, the effect of high-intensity exercise has not been investigated. This study examined the effect of low-volume, high-intensity interval running (HIIR) on postprandial plasma triacylglycerol (TAG) concentrations. Fifteen healthy, active boys (means ± SD; age = 11.8 ± 0.4 yr, body mass = 42.8 ± 8.0 kg, peak oxygen uptake [VO2] = 55 ± 6 mL · kg(-1) · min(-1)) completed two 2-d trials in a counterbalanced, crossover design separated by 14 d. On day 1, participants rested (CON) or completed 10 × 1 min running intervals at 100% maximal aerobic speed, determined from an incremental peak VO2 test, with 1 min recovery between intervals (HIIR). On day 2, capillary blood samples were taken in the fasted state and at predetermined intervals throughout the 6.5-h postprandial period while participants rested. A standardized breakfast was consumed at 0800 h, immediately after the fasting sample, and a standardized lunch meal was consumed at 1200 h. Differences in fasting plasma TAG concentration were small to moderate (95% confidence interval [CI] = -0.11 to 0.01, effect size [ES] = 0.40). Postprandial TAG concentration was lower during HIIR compared with CON (95% CI = -0.19 to -0.02, ES = 0.58). The total area under the TAG concentration versus time curve was lower after HIIR compared with CON (5.2 ± 1.1 vs 5.8 ± 1.5 mmol(-1) · L 6.5 h; 95% CI = -1.18 to -0.12, ES = 0.50). This is the first study to show that low-volume HIIR attenuates postprandial TAG concentration in healthy, active 11- to 12-yr-old boys.

Carboxylesterase1/Esterase-x Regulates Chylomicron Production in Mice

Elevated postprandial plasma triacylglycerol (TG) concentrations are commonly associated with obesity and the risk of cardiovascular disease. Dietary fat contributes to this condition through the production of chylomicrons. Carboxylesterases have been mainly studied for their role in drug metabolism, but recently they have been shown to participate in lipid metabolism; however, their role in intestinal lipid metabolism is unknown. Carboxylesterase1/esterase-x (Ces1/Es-x) deficient mice become obese, hyperlipidemic and develop hepatic steatosis even on standard chow diet. Here, we aimed to explore the role of Ces1/Es-x in intestinal lipid metabolism. Six-month old wild-type and Ces1/Es-x deficient mice were maintained on chow diet and intestinal lipid metabolism and plasma chylomicron clearance were analyzed. Along the intestine Ces1/Es-x protein is expressed only in proximal jejunum. Ablation of Ces1/Es-x expression results in postprandial hyperlipidemia due to increased secretion of chylomicrons. The secreted chylomicrons have aberrant protein composition, which results in their reduced clearance. In conclusion, Ces1/Es-x participates in the regulation of chylomicron assembly and secretion. Ces1/Es-x might act as a lipid sensor in enterocytes regulating chylomicron secretion rate. Ces1/Es-x might represent an attractive pharmacological target for the treatment of lipid abnormalities associated with obesity, insulin resistance and fatty liver disease.

Dietary fat manipulation has a greater impact on postprandial lipid metabolism than the apolipoprotein E (epsilon) genotype–insights from the SATgenε study

Our aim was to determine the effects of chronic dietary fat manipulation on postprandial lipaemia according to apolipoprotein (APO)E genotype. Men (mean age 53 (SD 9) years), prospectively recruited for the APOE genotype (n = 12 E3/E3, n = 11 E3/E4), were assigned to a low fat (LF), high fat, high-saturated fat (HSF), and HSF diet with 3.45 g/day docosahexaenoic acid (HSF-DHA), each for an 8-week period in the same order. At the end of each dietary period, a postprandial assessment was performed using a test meal with a macronutrient profile representative of that dietary intervention. A variable postprandial plasma triacylglycerol (TAG) response according to APOE genotype was evident, with a greater sensitivity to the TAG-lowering effects of DHA in APOE4 carriers (p ≤ 0.005). There was a lack of an independent genotype effect on any of the lipid measures. In the groups combined, dietary fat manipulation had a significant impact on lipids in plasma and Svedberg flotation rate (S(f) ) 60-400 TAG-rich lipoprotein fraction, with lower responses following the HSF-DHA than HSF intervention (p < 0.05). Although a modest impact of APOE genotype was observed on the plasma TAG profile, dietary fat manipulation emerged as a greater modulator of the postprandial lipid response in normolipidaemic men.

Increased plasma availability of l-arginine in the postprandial period decreases the postprandial lipemia in older adults

ObjectiveOlder adults have exaggerated postprandial lipemia, which increases their risk for cardiovascular disease. We sought to determine the effects of increased plasma l-arginine (L-ARG) availability on the oxidation of ingested fat (enriched with [1,1,1-13C]-triolein) and plasma triacylglycerol (TG) concentrations during the postprandial period in older subjects. MethodsOn one day, eight healthy subjects (67.8 ± 1.3 y old) received an intravenous infusion of L-ARG during the first hour of the postprandial period (L-ARG trial), while on a separate day, and in a randomized order, they received saline (control trial). ResultsThe 8-h area under the plasma concentration–time curve describing the postprandial plasma TG concentrations was considerably lower in the L-ARG trial than in the control trial (−4 ± 21 versus 104 ± 21 mg ∙ dL−1 ∙ h−1, P < 0.01). The rate of the postprandial oxidation of the ingested lipid was not different between the trials, but the average contribution of the ingested oleate to the oleate of the TG of the plasma small TG-rich lipoproteins (Svedberg flotation index 20–400) was lower in the L-ARG trial (11 ± 1 versus 18 ± 2%, P < 0.01). L-ARG infusion also decreased the 8-h area under the plasma concentration–time curve of the plasma free fatty acid concentrations derived from the ingested fat compared with the saline infusion (0.77 ± 0.09 versus 1.11 ± 0.08; mmol ∙ L−1 ∙ h−1, P < 0.01). ConclusionIncreasing the plasma L-ARG availability during the postprandial period decreases the postprandial lipemia in older adults, in association with a decrease in the postprandial contribution of ingested lipids into TGs of the plasma small TG-rich lipoproteins.

Effect of interrupting sitting time on acute postprandial lipemia in healthy children

Introduction: Sedentary behaviour in children has been associated with unhealthy dietary intake, and obesity levels in adulthood. Interrupting sitting time has been shown to improve metabolic health in adults but to date no studies have been conducted on metabolic risk factors in children. The aim of this study was to investigate the effect of interrupting sitting time on acute postprandial plasma triacylglycerol (TAG) in healthy children during the day following four high fat meals.

Identification of Diacylglycerol Acyltransferase Inhibitors from Rosa centifolia Petals

Diacylglycerol acyltransferase (DGAT) catalyzes the final step of triacylglycerol (TAG) synthesis, and is considered as a potential target to control hypertriglyceridemia or other metabolic disorders. In this study, we found that the extract of rose petals suppressed TAG synthesis in cultured cells, and that the extract showed DGAT inhibitory action in a dose-dependent manner. Fractionation of the rose extract revealed that the DGAT inhibitory substances in the extract were ellagitannins; among them rugosin B, and D, and eusupinin A inhibited DGAT activity by 96, 82, and 84% respectively, at 10μM. These substances did not inhibit the activities of other hepatic microsomal enzymes, glucose-6-phosphatase and HMG-CoA reductase, or pancreatic lipase, suggesting that ellagitannins inhibit DGAT preferentially. In an oral fat load test using mice, postprandial plasma TAG increase was suppressed by rose extract; TAG levels 2h after the fat load were significantly lower in mice administered a fat emulsion containing rose extract than in control mice (446.3±33.1 vs 345.3±25.0mg/dL, control vs rose extract group; P<0.05). These results suggest that rose ellagitannins or rose extract could be beneficial in controlling lipid metabolism and used to improve metabolic disorders.