Postprandial hyperglycemia impairs vascular endothelial function in healthy men by inducing lipid peroxidation and increasing asymmetric dimethylarginine:arginine

Acute inflammatory and metabolic effect of high fructose intake in normal-weight women: A randomized, double-masked, crossover trial

OBJECTIVES

We aimed to evaluate the acute effect of a fructose-rich single meal on metabolic and inflammatory biomarkers RESEARCH METHODS AND PROCEDURES: This single-center, double-masked, randomized crossover trial recruited females aged 20 to 47 with a normal body mass index and was conducted at Hospital das Clínicas (Belo Horizonte, MG, Brazil). Participants received a standardized meal with either sucrose, glucose, or a fructose overload. Blood samples were collected after overnight fasting (baseline) and at 30, 60, 120, and 240 minutes postprandial. Serum levels of glucose, triglycerides (primary outcome), total cholesterol, alanine aminotransferase, aspartate aminotransferase, adiponectin, leptin, resistin, interleukin (IL)-2, IL-4, IL-5, IL-6, IL-10, IL-17, interferon-gamma, tumor necrosis factor, eotaxin, and total blood leukocytes were measured.

RESULTS

This trial was completed with 25 enrolled participants, and three dropped out. The per-protocol analysis included 22 participants. As expected, postprandial glycemia increased 30 minutes after consuming meals rich in sucrose (P = 0.045) or glucose (P < 0.001). Triglyceride and leucocyte concentrations increased only at 240 minutes after consuming a high-fructose meal (P < 0.05). Regardless of the type of carbohydrate overload, leptin concentrations decreased postprandially compared to baseline at all time points (P < 0.05). Four participants reported adverse events after consuming the standardized meal with glucose or fructose, including nausea and malaise.

CONCLUSIONS

Our findings indicate that a fructose-rich single meal leads to a more significant increase in triglyceride and leukocyte concentrations compared to glucose and sucrose in healthy women. These findings support concerns regarding the potential inflammatory and metabolic dysfunction associated with frequent consumption of high-fructose meals.

Altered oxidant and antioxidant levels are associated with vascular stiffness and diabetic kidney disease in type 1 diabetes after exposure to acute and chronic hyperglycemia

BACKGROUND

Hyperglycemia-induced oxidative stress is a well-established pathological mediator of vascular complications in diabetes. We assessed plasma oxidant and antioxidant levels in response to acute and chronic hyperglycemia in relation to vascular stiffness and varying degrees of kidney disease in type 1 diabetes individuals.

METHODS

The acute hyperglycemia study included 22 type 1 diabetic individuals with normal albumin excretion rate (AER) and 13 non-diabetic controls. These individuals received an acute glucose challenge during a 120-minute hyperglycemic clamp. The chronic hyperglycemia study included 118 type 1 diabetic individuals with chronically low (n = 60) or high (n = 58) HbA1c concentrations and varying degrees of diabetic kidney disease (DKD) classified as normal, moderate, or severe albuminuria (AER). Levels of malondialdehyde (MDA), reactive oxygen metabolites (ROMs), total antioxidant capacity (TAC), biological antioxidant potential (BAP) and superoxide dismutase (SOD) were measured from plasma or serum samples in the FinnDiane study.

RESULTS

Levels of MDA (p < 0.01) and ROMs (p < 0.01) were elevated in type 1 diabetes individuals compared to non-diabetic controls at baseline. Acute hyperglycemia further increased MDA levels (p < 0.05) and sustained the elevation of ROMs in type 1 diabetes individuals. Acute hyperglycemic challenge impaired TAC in both non-diabetic (p < 0.05) and type 1 diabetes (p < 0.01) individuals compared to baseline whereas BAP was increased (p < 0.05) with no difference observed in non-diabetic controls. There was a positive association between high circulating MDA and AIx (r2 = 0.611, p = 0.05), and between delta ROMs and delta AIx (r2 = 0.955, p = 0.014) in combined analysis of individuals with type 1 diabetes and non-diabetic controls. Type 1 diabetes individuals with varying status of DKD, showed elevated levels of ROMs in those with high HbA1c compared to their counterpart with low HbA1c (p < 0.05). Individuals with severe albuminuria showed elevated ROM levels (p < 0.01) and depressed antioxidant capacity (p < 0.01) compared to those with normal AER of comparable HbA1c concentrations.

CONCLUSIONS

Biomarkers of oxidative stress are associated with vascular stiffness and DKD following acute and chronic hyperglycemic exposure and may provide added value to HbA1c in understanding disease pathology, predicting risk and assessing the status of secondary complications of type 1 diabetes.

In silico analysis reveals α-amylase inhibitory potential of Taraxerol (Coccinia indica) and Epoxywithanolide-1 (Withania coagulans): a possible way to control postprandial hyperglycemia-induced endothelial dysfunction and cardiovascular events

Postprandial hyperglycemia (PPG) exacerbates endothelial dysfunction and impairs vascular function in diabetes as well in healthy people. Though synthetic drugs are available to regulate PPG, the severe gastrointestinal side effects of those medications have prompted the search for alternative treatments. Recently, some phytochemicals captured the attention because of their inhibitory effects on α-amylase to control diabetes. The aim of this study was to investigate and identify potential alpha-amylase inhibitors in C. indica and W. coagulans. This study also aims to understand one of the possible mechanisms of action of plants for their anti-diabetic activity. A total of 36 phytochemical ligands were subjected for protein-ligand docking analysis. Among the phytochemicals, Taraxerol and Epoxywithanolide-I demonstrated significant binding free energy of - 10.2 kcal/mol and - 11.9 kcal/mol respectively, which was higher than the reference acarbose with - 8.6 kcal/mol. These molecules were subjected for molecular dynamics simulation (MDS) analysis with alpha-amylase protein for a duration of 150 ns. Among the three complexes, Taraxerol and Epoxywithanolide-I complexes demonstrates strong potential as inhibitors of the target protein. MDS results were analyzed via root mean square deviation (RMSD), fluctuation of residues, potential energy, radii of gyration and solvent access surface area analysis. Taraxerol demonstrated a significantly low potential energy of - 1,924,605.25 kJ/mol, and Epoxywithanolide-I demonstrated - 1,964,113.3 kJ/mol of potential energy. RMSD plot shows that Epoxywithanolide-I has much higher stability than the other MDS complexes. Drugability and toxicity studies show that the test ligands are demonstrating strong potential as drug like molecules. The results of the study conclude that, Taraxerol of C. indica and Epoxywithanolide-I of W. coagulans are strong inhibitors of alpha-amylase enzyme and that, this is one of the possible mechanisms of action of the plants for their reported anti-diabetic activities. Further in-vitro analysis is in demand to prove the observed results.

Habitual isomaltulose intake reduces arterial stiffness associated with postprandial hyperglycemia in middle-aged and elderly people: a randomized controlled trial

Endothelin-1 (ET-1), produced by vascular endothelial cells, plays a pivotal role in the regulation of vascular tone. Isomaltulose, a naturally occurring sweetener and structural isomer of sucrose, reduces postprandial hyperglycemia, but its effect on arteriosclerosis due to hyperglycemia is unknown. The effects of 12 weeks of isomaltulose administration on ET-1 levels, a peptide that regulates arterial stiffness, blood pressure, and vascular tone, were tested before and after an oral glucose tolerance test. Fifty-four healthy middle-aged and older adults (30 men and 24 women) were divided into two groups: (1) a 25 g isomaltulose jelly drink intake group (Group I, 27 participants, mean age 55 ± 1 years) and (2) a sucrose jelly drink intake group (Group S, 27 participants, mean age 55 ± 1 years), each consuming isomaltulose or sucrose daily for 12 weeks, and a randomized, controlled study was conducted. Participants visited the laboratory before the intervention and 4, 8, and 12 weeks after the intervention to measure carotid-femoral (cf) and brachial-ankle (ba) pulse wave velocity (PWV), systolic blood pressure (BP), plasma glucose (PG), insulin, and ET-1 levels before and 60 and 120 min after a 75-g OGTT. baPWV, and ET-1 levels before intervention were significantly increased after 75-g OGTT compared to before 75-g OGTT in both groups (p < 0.05). The post-intervention baPWV, and ET-1 levels were significantly increased after 75-g OGTT in Group S compared to before 75-g OGTT (p < 0.05), whereas no significant changes were observed in Group I. These results suggest that consumption of isomaltulose, which has a lower GI than sucrose, is more effective in preventing the increases in systemic arterial stiffness associated with postprandial hyperglycemia in healthy middle-aged and older adults.

Skipping breakfast does not accelerate the hyperglycemia-induced endothelial dysfunction but reduces blood flow of the brachial artery in young men

PURPOSE

Postprandial hyperglycemia is assumed to have a negative impact on flow-mediated dilation (FMD), an index of endothelial function, and blood flow of the peripheral conduit arteries. This study aimed to determine whether the enhancement of postprandial hyperglycemia by skipping breakfast accelerates endothelial dysfunction and reduces the blood flow in the brachial artery in young men.

METHODS

Using a randomized cross-over design, ten healthy men completed two trials: with and without breakfast (Eating and Fasting trials, respectively). Venous blood sampling and brachial FMD tests were conducted before, 30, 60, 90, and 120 min after a 75-g oral glucose tolerance test (OGTT).

RESULTS

Skipping breakfast boosted post-OGTT glucose levels than having breakfast (P = 0.01). The magnitude of the decrease in FMD via OGTT did not vary between trials (main effect of trial P = 0.55). Although brachial blood flow tended to decrease after OGTT in both trials (interaction and main effect of time P = 0.61 and P = 0.054, respectively), the decrease in blood flow following OGTT was greater in the Fasting trial than in the Eating trial (main effect of trial, mean difference =  - 15.8 mL/min [95%CI =  - 25.6 to - 6.0 mL/min], P < 0.01).

CONCLUSION

Skipping breakfast did not enhance the magnitude of the decrease in FMD following glucose loading, but did accelerate hyperglycemia-induced reduction in brachial blood flow. Current findings suggest that even missing one breakfast has negative impacts on the blood flow regulation of the peripheral conduit arteries in young men who habitually eat breakfast.

No acute hyperglycemia induced impairment in brachial artery flow-mediated dilation before or after aerobic exercise training in young recreationally active males

There is some evidence that transient endothelial dysfunction induced by acute hyperglycemia may be attenuated by a single bout of aerobic exercise. However, the impact of aerobic exercise training on acute hyperglycemia-induced endothelial dysfunction has not been explored. The purpose of this study was to determine the impact of aerobic exercise training on the endothelial function response to acute hyperglycemia. Brachial artery flow-mediated dilation (FMD) was assessed in 24 healthy males (21 ± 1 years) pre-, 60 and 90 min post ingestion of 75 g of glucose. Participants completed a four-week control (CON; n = 13) or exercise training (EX; n = 11) intervention. The EX group completed four weeks of cycling exercise (30 min, 4×/week at 65% work rate peak). Cardiorespiratory fitness ([Formula: see text]O2peak) increased and resting HR decreased in EX, but not CON post-intervention (p < 0.001). Glucose and insulin increased (p < 0.001) following glucose ingestion, with no significant difference pre- and post-intervention. In contrast to previous research, FMD was unaffected by glucose-ingestion, pre- and post-intervention in both groups. In conclusion, acute hyperglycemia did not impair endothelial function, before or after exercise training. Relatively high baseline fitness ([Formula: see text]O2peak ~ 46 mL/kg/min) and young age may have contributed to the lack of impairment observed. Further research is needed to examine the impact of exercise training on hyperglycemia-induced impairments in endothelial function in sedentary males and females.

Ginsenoside Rb1 Reduces Hyper-Vasoconstriction Induced by High Glucose and Endothelial Dysfunction in Rat Aorta

Acute hyperglycemia induces oxidative damage and inflammation, leading to vascular dysfunction. Ginsenoside Rb1 (Rb1) is a major component of red ginseng with anti-diabetic, anti-oxidant and anti-inflammatory properties. Here, we investigated the beneficial effects and the underlying mechanisms of Rb1 on hypercontraction induced by high glucose (HG) and endothelial dysfunction (ED). The isometric tension of aortic rings was measured by myography. The rings were treated with NG-nitro-L-arginine methyl ester (L-NAME) to induce chemical destruction of the endothelium, and Rb1 was added after HG induction. The agonist-induced vasoconstriction was significantly higher in the aortic rings treated with L-NAME + HG50 than in those treated with HG50 or L-NAME (p = 0.011) alone. Rb1 significantly reduced the hypercontraction in the aortic rings treated with L-NAME + HG50 (p = 0.004). The ATP-sensitive K+ channel (KATP) blocker glibenclamide tended to increase the Rb1-associated reduction in the agonist-induced vasoconstriction in the rings treated with L-NAME + HG50. The effect of Rb1 in the aortic rings treated with L-NAME + HG50 resulted from a decrease in extracellular Ca2+ influx through the receptor-operated Ca2+ channel (ROCC, 10-6-10-4 M CaCl2, p < 0.001; 10-3-2.5 × 10-3 M CaCl2, p = 0.001) and the voltage-gated Ca2+ channel (VGCC, 10-6 M CaCl2, p = 0.003; 10-5-10-2 M CaCl2, p < 0.001), whereas Rb1 did not interfere with Ca2+ release from the sarcoplasmic reticulum. In conclusion, we found that Rb1 reduced hyper-vasoconstriction induced by HG and ED by inhibiting the ROCC and the VGCC, and possibly by activating the KATP in rat aorta. This study provides further evidence that Rb1 could be developed as a therapeutic target for ED in diabetes.

The Effect of Watermelon Juice Supplementation on Heart Rate Variability and Metabolic Response during an Oral Glucose Challenge: A Randomized, Double-Blind, Placebo-Controlled Crossover Trial

Heart rate variability (HRV) provides a simple method to evaluate autonomic function in health and disease. A reduction in HRV may indicate autonomic dysfunction and is strongly associated with aspects of cardiometabolic disease, including hyperglycemia. Reduced nitric oxide (NO) bioavailability is also implicated in the development of cardiometabolic disease and autonomic dysfunction. Watermelons are natural sources of L-arginine and L-citrulline, substrates used for NO synthesis. Watermelon consumption can improve NO bioavailability. We conducted a randomized, double-blind, placebo-controlled crossover trial to test the effects of 2 weeks of daily watermelon juice (WMJ) supplementation on HRV in response to an oral glucose challenge (OGC) in healthy young adults. We also performed indirect calorimetry to assess if our intervention altered the metabolic response to the OGC. WMJ supplementation preserved high-frequency power (HF) (treatment effect, p = 0.03) and the percentage of successive differences that differ by more than 50 ms (pNN50) (treatment effect, p = 0.009) when compared to the placebo treatment. There was no difference in resting energy expenditure or substate oxidation according to treatment. We report that WMJ supplementation attenuates OGC-induced reductions in HRV. Future work should emphasize the importance of NO bioavailability in autonomic dysfunction in cardiometabolic disease.

Protective Role of Chronic Exercise Training in Modulating the Impact of Hyperglycemia on Vascular Sensitivity to Ischemia-Reperfusion

Hyperglycemia (HG) is associated with increased mortality and morbidity in acute ischemic events. Regardless of the tissue or organs involved, the vascular endothelium is a key target of ischemia-reperfusion (I/R) injury severity. Among endothelium-protective strategies, exercise has been widely described as useful. However, whether this strategy is able to impact the deleterious effect of HG on endothelial function during I/R has never been challenged. For this, 48 male Wistar rats were randomized into 4 groups: sedentary (Sed) or exercised (Ex, 45 min/day, 5 days/week for 5 weeks) rats, treated (hyperglycemic, HG) or not (normoglycemic, NG) with streptozotocin (40 mg/kg, 48 h before procedure). Vascular I/R (120/15 min) was performed by clamping the femoral artery. Arterial and downstream muscular perfusions were assessed using laser speckle contrast imaging. Vascular endothelial function was assessed in vivo 15 min after reperfusion. HG was responsible for impairment of reperfusion blood flow as well as endothelial function. Interestingly exercise was able to prevent those impairments in the HG group. In agreement with the previous results, HG increased reactive oxygen species production and decreased nitric oxide bioavailability whereas exercise training normalized these parameters. It, therefore, appears that exercise may be an effective prevention strategy against the exacerbation of vascular and muscular damage by hyperglycemia during I/R.

Effects of Polyphenols on Glucose-Induced Metabolic Changes in Healthy Human Subjects and on Glucose Transporters

Dietary polyphenols interact with glucose transporters in the small intestine and modulate glucose uptake after food or beverage consumption. This review assesses the transporter interaction in vitro and how this translates to an effect in healthy volunteers consuming glucose. As examples, the apple polyphenol phlorizin inhibits sodium-glucose linked transporter-1; in the intestinal lumen, it is converted to phloretin, a strong inhibitor of glucose transporter-2 (GLUT2), by the brush border digestive enzyme lactase. Consequently, an apple extract rich in phlorizin attenuates blood glucose and insulin in healthy volunteers after a glucose challenge. On the other hand, the olive phenolic, oleuropein, inhibits GLUT2, but the strength of the inhibition is not enough to modulate blood glucose after a glucose challenge in healthy volunteers. Multiple metabolic effects and oxidative stresses after glucose consumption include insulin, incretin hormones, fatty acids, amino acids, and protein markers. However, apart from acute postprandial effects on glucose, insulin, and some incretin hormones, very little is known about the acute effects of polyphenols on these glucose-induced secondary effects. In summary, attenuation of the effect of a glucose challenge in vivo is only observed when polyphenols are strong inhibitors of glucose transporters.

Quality of dietary carbohydrate is more important than its quantity in lipid peroxidation

BACKGROUND

High glycemic index (GI) diets have been linked to elevated risk of cardiometabolic diseases. One possible underlying mechanism comes from high GI diet's potential to promote lipid peroxidation.

OBJECTIVES

We aim to evaluate whether and to what extent dietary carbohydrate quality and quantity are associated with systemic levels of lipid peroxidation in females.

METHODS

In this cross-sectional analysis of 2163 middle-aged women, a subset of the Shanghai Women's Health Study, we measured lipid peroxidation biomarkers F2-isoprostanes (F2-IsoPs) and its metabolite, 2,3-dinor-5,6-dihydro-15-F2t-IsoP (F2-IsoP-M), in urine. The quality of carbohydrate was defined by dietary GI, assessed using a validated FFQ via in-person interviews. A multivariable linear regression model with restricted cubic spline functions was used to evaluate the association of measured biomarkers with carbohydrate intake and dietary GI.

RESULTS

After adjustment for potential confounding factors such as cigarette smoking, BMI, and comorbidities, among others, we found that F2-IsoP-M concentrations were positively associated with both carbohydrate intake and dietary GI. Carbohydrate intake and dietary GI were weakly correlated (r = 0.12). When further mutually adjusted for the 2 factors, the positive association with F2-IsoP-M remained statistically significant for GI (P = 0.004) but not for carbohydrate intake (P = 0.50). Compared with those in the 10th percentile of dietary GI, fold increases (95% CI) in F2-IsoP-M concentrations for those in the 30th, 50th, 70th, and 90th percentiles were 1.03 (1.00, 1.07), 1.06 (1.01, 1.10), 1.09 (1.03, 1.14), and 1.13 (1.05, 1.21), respectively. Moreover, there appeared a threshold regarding the association between dietary GI and F2-IsoP-M concentrations, with the dose-effect slope of GI being 2.3 times greater when GI was ≥75 relative to GI <75.

CONCLUSIONS

This study provides evidence that the quality of dietary carbohydrate may be more important than the quantity of the intake with regard to systemic lipid peroxidation.

Endothelial Dysfunction Is Associated with Decreased Nitric Oxide Bioavailability in Dysglycaemic Subjects and First-Degree Relatives of Type 2 Diabetic Patients

Oxidative stress plays an important role in the pathogenesis of diabetes. We investigated oxidative stress and nitrite/nitrate concentrations at baseline and during postprandial hyperglycaemia in 40 first-degree relatives (FDRs) of diabetic patients with normal oral glucose tolerance test (OGTT) results, 40 subjects with abnormal OGTT results (dysglycaemic) and 20 subjects with normal OGTT results (normoglycaemic). Malondialdehyde (MDA), protein carbonyls (PCs), nitrite/nitrate plasma levels, the perfused boundary region (PBR—Glycocheck) of the sublingual microvessels, a marker of glycocalyx integrity, coronary flow reserve (CFR) and left ventricular global longitudinal strain (GLS) were assessed at 0 and 120 min of the OGTT. Insulin sensitivity was evaluated using Matsuda and the insulin sensitivity index (ISI). In all subjects, there were no significant changes in MDA or PC after the OGTT (p > 0.05). Compared with normoglycaemic subjects, FDRs and dysglycaemic subjects had significantly decreased nitrite/nitrate levels (−3% vs. −24% vs. −30%, respectively), an increased PBR and reduced CFR and GLS at 120 min (p < 0.05). The percent reduction in nitrite/nitrate was associated with abnormal Matsuda and ISI results, reversely related with the percent increase in PBR (r = −0.60) and positively related with the percent decrease in CFR (r = 0.39) and GLS (r = 0.48) (p < 0.05). Insulin resistance is associated with reduced nitric oxide bioavailability and coronary and myocardial dysfunction in FDRs and dysglycaemic subjects.

Sugar Consumption Is Negatively Associated with Semen Quality

Recently, in parallel to decrease in semen quality, the consumption of sugar has risen sharply. This provided the rationale to study the association between whole dietary sugar consumption and semen quality. Our aim was to investigate the association between sugar consumption and semen quality. The final cross-sectional study population (n = 280 of initial n = 593, after applying inclusion and exclusion criteria) attending routine semen analysis at sperm bank laboratory was subject to semen quality analysis according to WHO criteria (volume, sperm concentration, total sperm count, percentage total motility, and percentage normal morphology) and filled food frequency questionnaire (FFQ) and lifestyle questionnaire. Associations between consumed sugars and semen quality were analyzed using multivariate regression adjusted to relevant cofounders for 2 food components containing sugar including soft drinks (SoftD) and total added sugar to food products (SugProd). We found negative association between higher consumption of dietary sugar in all 2 dietary sub-categories and sperm concentration. Significant sperm concentration decrements of 18% and 23% were associated with SoftD median consumption of 0.2 drinks/day (IQR; 0.1-0.5 drinks/day). Significant sperm concentration decrements of 15% and 17% were associated with median SugProd consumption of 25 teaspoons of added sugar/day (IQR; 19-31 teaspoons of added sugar/day). In conclusion, our study findings demonstrate that sugar consumption is negatively associated with sperm concentration.

Feasibility of home-based tracking of insulin resistance from vascular stiffness estimated from the photoplethysmographic finger pulse waveform

In this study, we explored the utility of post-prandial vascular stiffness as a surrogate measure for the estimation of insulin resistance (IR), which is a pre-diabetic condition. A cohort of 51 healthy young adults of varying Body mass index values (BMI) were studied by fasting plasma values of insulin and glucose; fasting and post-meal finger photoplethysmography (PPG), and electrocardiogram (ECG). Insulin resistance was estimated by Homeostatic model assessment-Insulin resistance 2 (HOMA-IR2) using fasting plasma insulin and glucose. Vascular stiffness was estimated by reciprocal of pulse arrival time (rPAT) from ECG and finger PPG at five time points from fasting to 2-hours post oral glucose ingestion. We examined if insulin resistance is correlated with meal induced vascular stiffness changes supporting the feasibility of using finger PPG for the estimation of insulin resistance. HOMA-IR2 was found to be positively correlated with early rise (0- to 30- minutes post meal) and delayed fall (30- to 120-minutes) of rPAT. Correlation persisted even after the effect of BMI has been partialled out in sub-group analysis. We conclude that finger PPG based pulse waveform and single lead ECG has the potential to be used as a non-invasive method for the assessment of insulin resistance. As both signals viz., ECG and PPG can be easily acquired using wearable and other low-cost sensing systems, the present study can serve as a pointer for the development of accessible methods of monitoring and longitudinal tracking of insulin resistance in health and pathophysiological states.

Daily Inclusion of Resistant Starch-Containing Potatoes in a Dietary Guidelines for Americans Dietary Pattern Does Not Adversely Affect Cardiometabolic Risk or Intestinal Permeability in Adults with Metabolic Syndrome: A Randomized Controlled Trial

Poor diet quality influences cardiometabolic risk. Although potatoes are suggested to adversely affect cardiometabolic health, controlled trials that can establish causality are limited. Consistent with potatoes being rich in micronutrients and resistant starch, we hypothesized that their inclusion in a Dietary Guidelines for Americans (DGA)-based dietary pattern would improve cardiometabolic and gut health in metabolic syndrome (MetS) persons. In a randomized cross-over trial, MetS persons (n = 27; 32.5 ± 1.3 year) consumed a DGA-based diet for 2 weeks containing potatoes (DGA + POTATO; 17.5 g/day resistant starch) or bagels (DGA + BAGEL; 0 g/day resistant starch) prior to completing oral glucose and gut permeability tests. Blood pressure, fasting glucose and insulin, and insulin resistance decreased (p < 0.05) from baseline regardless of treatment without any change in body mass. Oral glucose-induced changes in brachial artery flow-mediated dilation, nitric oxide homeostasis, and lipid peroxidation did not differ between treatment arms. Serum endotoxin AUC0−120 min and urinary lactulose/mannitol, but not urinary sucralose/erythritol, were lower in DGA + POTATO. Fecal microbiome showed limited between-treatment differences, but the proportion of acetate was higher in DGA + POTATO. Thus, short-term consumption of a DGA-based diet decreases cardiometabolic risk, and the incorporation of resistant starch-containing potatoes into a healthy diet reduces small intestinal permeability and postprandial endotoxemia.

1-h Glucose During Oral Glucose Tolerance Test Predicts Hyperglycemia Relapse-Free Survival in Obese Black Patients With Hyperglycemic Crises

OBJECTIVE

Approximately 50% of obese Black patients with unprovoked diabetic ketoacidosis (DKA) or severe hyperglycemia (SH) at new-onset diabetes achieve near-normoglycemia remission with intensive insulin treatment. Despite the initial near-normoglycemia remission, most DKA/SH individuals develop hyperglycemia relapse after insulin discontinuation. Traditional biomarkers such as normal glucose tolerance at the time of remission were not predictive of hyperglycemia relapse. We tested whether 1-h plasma glucose (1-h PG) at remission predicts hyperglycemia relapse in Black patients with DKA/SH.

METHODS

Secondary analysis was performed of two prospective randomized controlled trials in 73 patients with DKA/SH at the safety net hospital with a median follow-up of 408 days. Patients with DKA/SH underwent a 5-point, 2-h 75-g oral glucose tolerance test after hyperglycemia remission. Hyperglycemia relapse is defined by fasting blood glucose (FBG) > 130 mg/dl, random blood glucose (BG) >180 mg/dl, or HbA1c > 7%.

RESULTS

During the median 408 (interquartile range: 110-602) days of follow-up, hyperglycemia relapse occurred in 28 (38.4%) participants. One-hour PG value ≥199 mg/dl discriminates hyperglycemia relapse (sensitivity: 64%; specificity: 71%). Elevated levels of 1-h PG (≥199 mg/dl) were independently associated with hyperglycemia relapse (adjusted hazard ratio: 2.40 [95% CI: 1.04, 5.56]). In a multivariable model with FBG, adding 1-h PG level enhanced the prediction of hyperglycemia relapse, with significant improvements in C-index (Δ: +0.05; p = 0.04), net reclassification improvement (NRI: 48.7%; p = 0.04), and integrated discrimination improvement (IDI: 7.8%; p = 0.02) as compared with the addition of 2-h PG (NRI: 20.2%; p = 0.42; IDI: 1.32%; p = 0.41) or HbA1c (NRI: 35.2%; p = 0.143; IDI: 5.8%; p = 0.04).

CONCLUSION

One-hour PG at the time of remission is a better predictor of hyperglycemia relapse than traditional glycemic markers among obese Black patients presenting with DKA/SH. Testing 1-h PG at insulin discontinuation identifies individuals at high risk of developing hyperglycemia relapse.

Effects of Different Types of Carbohydrates on Arterial Stiffness: A Comparison of Isomaltulose and Sucrose

Increased arterial stiffness during acute hyperglycemia is a risk factor for cardiovascular disease, but the type of carbohydrate that inhibits it is unknown. The purpose of this study was to determine the efficacy of low-glycemic-index isomaltulose on arterial stiffness during hyperglycemia in middle-aged and older adults. Ten healthy middle-aged and older adult subjects orally ingested a solution containing 25 g of isomaltulose (ISI trial) and sucrose (SSI trial) in a crossover study. In the SSI trial, the brachial-ankle (ba) pulse wave velocity (PWV) increased 30, 60, and 90 min after ingestion compared with that before ingestion (p < 0.01); however, in the ISI trial, the baPWV did not change after ingestion compared with that before ingestion. Blood glucose levels 30 min after intake were lower in the ISI trial than in the SSI trial (p < 0.01). The baPWV and systolic blood pressure were positively correlated 90 min after isomaltulose and sucrose ingestion (r = 0.640, p < 0.05). These results indicate that isomaltulose intake inhibits an acute increase in arterial stiffness. The results of the present study may have significant clinical implications on the implementation of dietary programs for middle-aged and elderly patients.

Microvascular Ageing Links Metabolic Disease to Age-Related Disorders: The Role of Oxidative Stress and Inflammation in Promoting Microvascular Dysfunction

ABSTRACT

Longer life span and increased prevalence of chronic, noncommunicable, inflammatory diseases fuel cardiovascular mortality. The microcirculation is central in the cross talk between ageing, inflammation, cardiovascular, and metabolic diseases. Microvascular dysfunction, characterized by alteration in the microvascular endothelial function and wall structure, is described in an increasing number of chronic age-associated diseases, suggesting that it might be a marker of ageing superior to chronological age. The aim of this review is to thoroughly explore the connections between microvascular dysfunction, ageing, and metabolic disorders by detailing the major role played by inflammation and oxidative stress in their evolution. Older age, hypertension, nutrient abundance, and hyperglycemia concur in the induction of a persistent low-grade inflammatory response, defined as meta-inflammation or inflammageing. This increases the local generation of reactive oxygen species that further impairs endothelial function and amplifies the local inflammatory response. Mitochondrial dysfunction is a hallmark of many age-related diseases. The alterations of mitochondrial function promote irreversible modification in microvascular structure. The interest in the hypothesis of chronic inflammation at the center of the ageing process lies in its therapeutic implications. Inhibition of specific inflammatory pathways has been shown to lower the risk of many age-related diseases, including cardiovascular disease. However, the whole architecture of the inflammatory response underpinning the ageing process and its impact on the burden of age-related diseases remain to be fully elucidated. Additional studies are needed to unravel the connection between these biological pathways and to address their therapeutic power in terms of cardiovascular prevention.

Supplemental Watermelon Juice Attenuates Acute Hyperglycemia-Induced Macro-and Microvascular Dysfunction in Healthy Adults

BACKGROUND

Acute hyperglycemia reduces NO bioavailability and causes macro- and microvascular dysfunction. Watermelon juice (WMJ) is a natural source of the amino acid citrulline, which is metabolized to form arginine for the NO cycle and may improve vascular function.

OBJECTIVES

We examined the effects of 2 weeks of WMJ compared to a calorie-matched placebo (PLA) to attenuate acute hyperglycemia-induced vascular dysfunction.

METHODS

In a randomized, placebo-controlled, double-blind, crossover trial, 6 men and 11 women (aged 21-25; BMI, 23.5 ± 3.2 kg/m2) received 2 weeks of daily WMJ (500 mL) or a PLA drink followed by an oral-glucose-tolerance test. Postprandial flow-mediated dilation (FMD) was measured by ultrasound (primary outcome), while postprandial microvascular blood flow (MVBF) and ischemic reperfusion were measured by near-infrared spectroscopy (NIRS) vascular occlusion test (VOT).

RESULTS

The postprandial FMD area AUC was higher after WMJ supplementation compared to PLA supplementation (838 ± 459% · 90 min compared with 539 ± 278% · 90 min; P = 0.03). The postprandial MVBF (AUC) was higher (P = 0.01) following WMJ supplementation (51.0 ± 29.1 mL blood · 100 mL tissue-1 · min-1 · 90 min) compared to the PLA (36.0 ± 20.5 mL blood · 100 mL tissue-1 · min-1 · 90 min; P = 0.01). There was a significant treatment effect (P = 0.048) for WMJ supplementation (71.2 ± 1.5%) to increase baseline tissue oxygen saturation (StO2%) when compared to PLA (65.9 ± 1.7%). The ischemic-reperfusion slope was not affected by WMJ treatment (P = 0.83).

CONCLUSIONS

Two weeks of daily WMJ supplementation improved FMD and some aspects of microvascular function (NIRS-VOT) during experimentally induced acute hyperglycemia in healthy adults. Preserved postprandial endothelial function and enhanced skeletal muscle StO2% are likely partially mediated by increased NO production (via citrulline conversion into arginine) and by the potential antioxidant effect of other bioactive compounds in WMJ.

Effects of Acute Fructose Loading on Markers of Inflammation-A Pilot Study

Inflammation plays a role in development of diabetic complications. The postprandial state has been linked to chronic low grade inflammation. We therefore aimed to investigate the acute effects of fructose loading, with and without a pizza, on metabolic and inflammatory markers in patients with type 2 diabetes (T2D) (n = 7) and in healthy subjects (HS) (n = 6), age 47–76 years. Drinks consumed were blueberry drink (18 g fructose), Coca-Cola (17.5 g fructose), and fructose drink (35 g fructose). The levels of glucose, insulin, insulin-like growth factor binding protein-1 (IGFBP-1) and inflammatory markers: Interleukin-6 (IL-6), Monocyte chemoattractant protein-1 (MCP-1), Interleukin-18 (IL-18), Intercellular Adhesion Molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and bacterial lipopolysaccharides (LPS) were analyzed in blood. The postprandial responses were assessed using Wilcoxon’s matched-pairs test, Friedman’s ANOVA and Mann–Whitney U test. There was no difference in baseline levels of inflammatory markers between the groups. In T2D, MCP-1 decreased following blueberry drink and Coca-Cola (p = 0.02), Coca-Cola + pizza and fructose + pizza (p = 0.03). In HS, IL-6 increased following blueberry + pizza and fructose + pizza (p = 0.03), there was a decrease in MCP-1 following blueberry drink and Coca-Cola (p = 0.03), and in ICAM-1 following blueberry + pizza (p = 0.03). These results may indicate a role for MCP-1 as a link between postprandial state and diabetes complications, however further mechanistic studies on larger population of patients with T2D are needed for confirmation of these results.

Propofol But Not Desflurane Maintains Rat Cerebral Arteriolar Responses to Acetylcholine During Acute Hyperglycemia

BACKGROUND

Acute hyperglycemia causes vascular endothelial dysfunction in various organs including the cerebral vessels. It is associated with increased mortality and morbidity in the perioperative period. The impact of anesthetic agents on cerebral vasodilatory responses during hyperglycemia remains unclear. We investigated endothelial function in rat cerebral arterioles during acute hyperglycemia, under propofol or desflurane anesthesia.

MATERIALS AND METHODS

A closed cranial window preparation was used to measure changes in pial arteriole diameter induced by topical application of acetylcholine (ACh), an endothelium-dependent vasodilator, in rats anesthetized with propofol or desflurane. Pial arteriole responses to ACh were measured during normoglycemia and hyperglycemia. We then investigated whether the response of cerebral arterioles to acute hyperglycemia under propofol anesthesia were related to propofol or its vehicle, intralipid.

RESULTS

ACh resulted in a dose-dependent dilation of cerebral arterioles during propofol and desflurane anesthesia under normoglycemic conditions. The vasodilatory effects of ACh were also maintained under hyperglycemic conditions during propofol anesthesia, but the vasodilator response to ACh was significantly impaired during hyperglycemia compared with normoglycemia with desflurane anesthesia. The vasodilatory effects of ACh were maintained during normoglycemia and hyperglycemia in rats receiving propofol or intralipid.

CONCLUSIONS

Rat pial arteriole responses to ACh are maintained during conditions of acute hyperglycemia with propofol anesthesia but suppressed compared with normoglycemia with desflurane anesthesia.

Mild obesity does not affect the forearm muscle microvascular responses to hyperglycemia

INTRODUCTION

Mild obesity has been associated with postprandial brachial artery vascular dysfunction. However, direct assessment of these effects within the forearm skeletal muscle microcirculation remains unclear. Thus, this study aimed to investigate the effects of mild obesity on the arm micro- and macrovascular responses to glucose ingestion.

METHODS

This cross-sectional study combined NIRS assessments of forearm skeletal muscle (FDS) reactivity (reperfusion slope) with %FMD of conduit artery function (brachial artery) before (Pre), as well as 60 and 120 min after glucose ingestion in 10 lean (BMI 23.9 ± 1.8) and 10 obese (BMI 32.9 ± 1.9) individuals.

RESULTS

Both groups showed a significant increase in the reperfusion slope at 60 and 120 min after glucose ingestion compared with the pre-glucose ingestion measurements. Obese individuals showed a significant (p < .05) reduction in %FMD at 60 min after glucose ingestion, while no significant changes in postprandial %FMD were observed in lean participants.

CONCLUSION

Even though obese individuals showed impaired postprandial brachial artery function, the current findings suggest that mild obesity does not affect the forearm skeletal muscle responses to glucose ingestion.

Type 2 diabetes and reduced exercise tolerance: a review of the literature through an integrated physiology approach

The association between type 2 diabetes mellitus (T2DM) and heart failure (HF) is well established. Early in the course of the diabetic disease, some degree of impaired exercise capacity (a powerful marker of health status with prognostic value) can be frequently highlighted in otherwise asymptomatic T2DM subjects. However, the literature is quite heterogeneous, and the underlying pathophysiologic mechanisms are far from clear. Imaging-cardiopulmonary exercise testing (CPET) is a non-invasive, provocative test providing a multi-variable assessment of pulmonary, cardiovascular, muscular, and cellular oxidative systems during exercise, capable of offering unique integrated pathophysiological information. With this review we aimed at defying the cardiorespiratory alterations revealed through imaging-CPET that appear specific of T2DM subjects without overt cardiovascular or pulmonary disease. In synthesis, there is compelling evidence indicating a reduction of peak workload, peak oxygen assumption, oxygen pulse, as well as ventilatory efficiency. On the contrary, evidence remains inconclusive about reduced peripheral oxygen extraction, impaired heart rate adjustment, and lower anaerobic threshold, compared to non-diabetic subjects. Based on the multiparametric evaluation provided by imaging-CPET, a dissection and a hierarchy of the underlying mechanisms can be obtained. Here we propose four possible integrated pathophysiological mechanisms, namely myocardiogenic, myogenic, vasculogenic and neurogenic. While each hypothesis alone can potentially explain the majority of the CPET alterations observed, seemingly different combinations exist in any given subject. Finally, a discussion on the effects -and on the physiological mechanisms-of physical activity and exercise training on oxygen uptake in T2DM subjects is also offered. The understanding of the early alterations in the cardiopulmonary response that are specific of T2DM would allow the early identification of those at a higher risk of developing HF and possibly help to understand the pathophysiological link between T2DM and HF.

A Protein/Lipid Preload Attenuates Glucose-Induced Endothelial Dysfunction in Individuals with Abnormal Glucose Tolerance

Postprandial hyperglycemia interferes with vascular reactivity and is a strong predictor of cardiovascular disease. Macronutrient preloads reduce postprandial hyperglycemia in subjects with impaired glucose tolerance (IGT) or type 2 diabetes (T2D), but the effect on endothelial function is unknown. Therefore, we examined whether a protein/lipid preload can attenuate postprandial endothelial dysfunction by lowering plasma glucose responses in subjects with IGT/T2D. Endothelial function was assessed by the reactive hyperemia index (RHI) at fasting, 60 min and 120 min during two 75 g oral glucose tolerance tests (OGTTs) preceded by either water or a macronutrient preload (i.e., egg and parmesan cheese) in 22 volunteers with IGT/T2D. Plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), glucagon, free fatty acids, and amino acids were measured through each test. RHI negatively correlated with fasting plasma glucose. During the control OGTT, RHI decreased by 9% and its deterioration was associated with the rise in plasma glucose. The macronutrient preload attenuated the decline in RHI and markedly reduced postprandial glycemia. The beneficial effect of the macronutrient preload on RHI was proportional to the improvement in glucose tolerance and was associated with the increase in plasma GLP-1 and arginine levels. In conclusion, a protein/lipid macronutrient preload attenuates glucose-induced endothelial dysfunction in individuals with IGT/T2D by lowering plasma glucose excursions and by increasing GLP-1 and arginine levels, which are known regulators of the nitric oxide vasodilator system.

Effect of warm environment on the skin blood flow response to food intake

BACKGROUND AND OBJECTIVE

Warm exposure places high demands on thermoregulation mechanisms, which depend on the effectiveness of the microvascular function. The associations between the microcirculation and metabolism in warm environments have received little attention. The purpose of this study was to explore skin blood flow (SkBF) in response to food intake in a warm environment compared to control.

METHODS

Thirty-two healthy, acclimated-to-warm-environment and physically active participants were recruited (20 females and 12 males). They participated in two sessions (warm environment: 31 °C and control: 20 °C, presented in randomized order). SkBF was measured before and after standardized food intake through the acquisition of perfusion signals by laser Doppler flowmetry (Periflux System 5000), following a local heating protocol.

RESULTS

SkBF was affected by the environmental temperature, showing an increase in the warm environment compared to control (all p < .001). SkBF was significantly affected by food intake (all p < .007), being reduced after meals. In the men's group, SkBF was reduced in both environmental temperatures after meals. In women, meals affected SkBF at 20 °C but not in the warm environment.

CONCLUSION

These results may indicate a competition between thermo- and glyco-regulation in a warm environment to the detriment of glucose homeostasis in women.

Effects of a short-term increase in physical activity on arterial stiffness during hyperglycemia

We examined the effects of increasing physical activity on arterial stiffness during hyperglycemia. Nineteen glucose-intolerant elderly participated in the study. We randomly assigned 10 participants to increase their daily activity in everyday life, regardless of the time or intensity, for 1 month (PAI group) (age, 74.6 ± 1.3 years; mean ± SE) and nine participants to maintain their level of activity (CON group) (age, 79.2 ± 2.1 years; mean ± SE). The 75-g oral glucose tolerance test was conducted in each participant in both groups before and after the start of the intervention to confirm glucose intolerance. Brachial-ankle pulse wave velocity and cardio-ankle vascular index significantly increased from baseline at 30, 60, and 90 min after the 75-g glucose ingestion after the intervention in the CON group (p<0.05), but not in the PAI group. Heart-brachial pulse wave velocity did not change compared to baseline after the 75-g glucose ingestion in either group and did not change from baseline at 30, 60, and 90 min after the 75-g glucose ingestion before and after the intervention in both groups. The present findings indicate that a short-term increase in physical activity suppresses the increase in arterial stiffness after glucose intake.

High-glucose mixed-nutrient meal ingestion impairs skeletal muscle microvascular blood flow in healthy young men

Oral glucose ingestion leads to impaired muscle microvascular blood flow (MBF), which may contribute to acute hyperglycemia-induced insulin resistance. We investigated whether incorporating lipids and protein into a high-glucose load would prevent postprandial MBF dysfunction. Ten healthy young men (age, 27 yr [24, 30], mean with lower and upper bounds of the 95% confidence interval; height, 180 cm [174, 185]; weight, 77 kg [70, 84]) ingested a high-glucose (1.1 g/kg glucose) mixed-nutrient meal (10 kcal/kg; 45% carbohydrate, 20% protein, and 35% fat) in the morning after an overnight fast. Femoral arterial blood flow was measured via Doppler ultrasound, and thigh MBF was measured via contrast-enhanced ultrasound, before meal ingestion and 1 h and 2 h postprandially. Blood glucose and plasma insulin were measured at baseline and every 15 min throughout the 2-h postprandial period. Compared with baseline, thigh muscle microvascular blood volume, velocity, and flow were significantly impaired at 60 min postprandial (-25%, -27%, and -46%, respectively; all P < 0.05) and to a greater extent at 120 min postprandial (-37%, -46%, and -64%; all P < 0.01). Heart rate and femoral arterial diameter, blood velocity, and blood flow were significantly increased at 60 min and 120 min postprandial (all P < 0.05). Higher blood glucose area under the curve was correlated with greater MBF dysfunction (R² = 0.742; P < 0.001). Ingestion of a high-glucose mixed-nutrient meal impairs MBF in healthy individuals for up to 2 h postprandial.

Antioxidant cocktail following a high-sodium meal does not affect vascular function in young, healthy adult humans: a randomized controlled crossover trial

Chronic high sodium intake is a risk factor for cardiovascular disease as it impairs vascular function through an increase in oxidative stress. The objective of this study was to investigate the acute effects of a high-sodium meal (HSM) and antioxidant (AO) cocktail on vascular function. We hypothesized that a HSM would impair endothelial function, and increase arterial stiffness and wave reflection, while ingestion of the AO cocktail would mitigate this response. Healthy adults ingested either an AO cocktail (vitamin C, E, alpha-lipoic acid) or placebo (PLA) followed by a HSM (1500 mg) in a randomized crossover blinded design. Blood pressure (BP), endothelial function (flow-mediated dilation; FMD) and measures of arterial stiffness (pulse wave velocity; PWV) and wave reflection (augmentation index; AIx) were made at baseline and 30, 60, 90, and 120 min after meal consumption. Forty-one participants (20M/21W; 24 ± 1 years; BMI 23.4 ± 0.4 kg/m²) completed the study. Mean BP increased at 120 min relative to 60 min (60 min: 79 ± 1; 120 min: 81 ± 1 mmHg; time effect P = .01) but was not different between treatments (treatment × time interaction P = .32). AIx decreased from baseline (time effect P < .001) but was not different between treatments (treatment × time interaction P = .31). PWV (treatment × time interaction, P = .91) and FMD (treatment × time interaction P = .65) were also not different between treatments. In conclusion, a HSM does not acutely impair vascular function suggesting young healthy adults can withstand the acute impact of sodium on the vasculature and therefore, the AO cocktail is not necessary to mitigate the response.

Aerobic exercise offsets endothelial dysfunction induced by repetitive consumption of sugar-sweetened beverages in young healthy men

Consumption of a single, sugar-sweetened beverage (SSB) impairs vascular endothelial function. Regular aerobic exercise improves endothelium-dependent vasodilation; however, it is unknown whether these beneficial effects persist with frequent SSB consumption. Therefore, the purpose of this study was twofold; we studied the effects of repetitive SSB consumption (75 g d-glucose, 3 times/day) for 1 wk (Glu, n = 13, 23 ± 4 yr, 23.5 ± 3.4 kg/m²) on endothelium-dependent vasodilation (FMD). Then, in a separate cohort, we investigated whether 45 min of moderate-intensity aerobic exercise on five separate days offset the hypothesized decrease in FMD during the Glu protocol (Glu+Ex, n = 11, 21 ± 3 yr, 23.8 ± 2.4 kg/m²). Baseline, fasting [glucose] (P = 0.15), [insulin] (P = 0.25), %FMD (P = 0.48), absolute FMD (P = 0.66), and shear rate area under the curve (SR_AUC; P = 0.82) were similar between groups. Following the interventions, fasting [glucose] (Glu: 94 ± 6 to 92 ± 6 mg/dL, Glu+Ex: 89 ± 8 to 87 ± 6 mg/dL, P = 0.74) and [insulin] (Glu: 11.3 ± 6.2 to 11.8 ± 8.9 μU/mL, Glu+Ex: 8.7 ± 2.9 to 9.4 ± 3.2 μU/mL, P = 0.89) were unchanged. %FMD was reduced in Glu (6.1 ± 2.2 to 5.1 ± 1.3%) and increased in Glu+Ex (6.6 ± 2.2 to 7.8 ± 2.4%, P < 0.05 for both). SR_AUC increased similarly in both Glu [17,715 ± 8,275 to 22,922 ± 4,808 arbitrary units (A.U.)] and Glu+Ex (18,216 ± 4,516 to 21,666 ± 5,392 A.U., main effect of time P < 0.05). When %FMD was adjusted for SR_AUC, attenuation was observed in Glu (0.41 ± 0.18 to 0.23 ± 0.08%/s × 103, P < 0.05) but not Glu+Ex (0.38 ± 0.14 to 0.38 ± 0.13%/s × 103, P = 0.88). Despite unchanged fasting [glucose] and [insulin], repeated consumption of SSBs impaired conduit artery vascular endothelial function. Additionally, subjects who engaged in regular moderate-intensity aerobic exercise did not demonstrate the same SSB-induced endothelial dysfunction. Collectively, these data suggest aerobic exercise may offset the deleterious effects of repetitive SSB consumption.

Efficacy of Isomaltulose Compared to Sucrose in Modulating Endothelial Function in Overweight Adults

Hyperglycemia is linked to impaired arterial endothelial function (EF), an early sign of cardiovascular disease. We compared the efficacy of low-glycemic index isomaltulose (Palatinose™) with that of sucrose in modulating EF, as assessed by flow-mediated dilation (FMD). In this double-blinded cross-over study, 80 overweight mildly hypertensive subjects were randomized to receive 50 g of either isomaltulose or sucrose. On two non-consecutive days, brachial artery ultrasound FMD scans were obtained prior to and hourly (T0-T3) after carbohydrate load. Blood was drawn immediately after scanning. Glucose and insulin levels were analyzed. Overall, the FMD decrease was attenuated by isomaltulose compared to sucrose (ΔFMD = -0.003% and -0.151%; p > 0.05 for the interaction treatment x period). At T2, FMD was significantly higher after isomaltulose administration compared to that after sucrose administration (FMD = 5.9 ± 2.9% and 5.4 ± 2.6%, p = 0.047). Pearson correlations between FMD and blood glucose showed a trend for a negative association at T0 and T2 independently of the carbohydrate (r-range = -0.20 to -0.23, p < 0.1). Sub-analysis suggested a lower FMD in insulin-resistant (IR) compared to insulin-sensitive subjects. Isomaltulose attenuated the postprandial decline of FMD, particularly in IR persons. These data support the potential of isomaltulose to preserve the endothelial function postprandially and consequently play a favorable role in cardiovascular health.

Increased systemic endothelial-dependent microvascular reactivity after ingestion of a high-carbohydrate snack in young, healthy volunteers

OBJECTIVE

This study evaluated the acute effect of a high-carbohydrate snack (HCS) on systemic microvascular function of healthy, young volunteers, using laser speckle contrast imaging (LSCI).

METHODS

Cutaneous microvascular blood flow was assessed in the forearm with LSCI coupled to iontophoresis of acetylcholine, using increasing anodal currents, before and after (25 min) the ingestion of a HCS or water (control). Twenty volunteers (10 male) received a single HCS (70 g of carbohydrates) in the fasting state in the morning.

RESULTS

The area under the curve (AUC) of acetylcholine-induced microvascular vasodilation increased from 17,847 ± 4539 to 20,315 ± 7168 arbitrary perfusion units/s (P = 0.03) after ingestion of a HCS, but was unchanged after the ingestion of water (P = 0.22).

CONCLUSION

A single snack consisting on an acute oral load of carbohydrates induced a significant increase of endothelium-dependent microvascular vasodilation in healthy, young subjects.

Effects of Glycemic Index and Cereal Fiber on Postprandial Endothelial Function, Glycemia, and Insulinemia in Healthy Adults

Both glycemic index and dietary fiber are associated with cardiovascular disease risk, which may be related in part to postprandial vascular effects. We examined the effects of both glycemic index (GI) and dietary (mainly cereal) fiber on postprandial endothelial function. Eleven adults (5 men; 6 women; age = 42.4 ± 16.1 years; weight = 70.5 ± 10.7 kg; height = 173.7 ± 8.7 cm) consumed four different breakfast meals on separate, randomized occasions: High-Fiber, Low-GI (HF-LGI: Fiber = 20.4 g; GI = 44); Low-Fiber, Low-GI (LF-LGI: Fiber = 4.3 g; GI = 43); Low-Fiber, High-GI (LF-HGI: Fiber = 3.6 g; GI = 70); High-Fiber, High-GI (HF-HGI: Fiber = 20.3 g; GI = 71). Meals were equal in total kcal (~600) and macronutrient composition (~90 g digestible carbohydrate; ~21 g protein; ~15 g fat). The HF-LGI meal resulted in a significant increase in flow-mediated dilation (FMD) 4 h after meal ingestion (7.8% ± 5.9% to 13.2% ± 5.5%; p = 0.02). FMD was not changed after the other meals. Regardless of fiber content, low-GI meals resulted in ~9% lower 4-h glucose area under curve (AUC) (p < 0.05). The HF-LGI meal produced the lowest 4-h insulin AUC, which was ~43% lower than LF-HGI and HF-HGI (p < 0.001), and 28% lower than LF-LGI (p = 0.02). We conclude that in healthy adults, a meal with low GI and high in cereal fiber enhances postprandial endothelial function. Although the effect of a low-GI meal on reducing postprandial glucose AUC was independent of fiber, the effect of a low-GI meal on reducing postprandial insulin AUC was augmented by cereal fiber.

Controlled Feeding of an 8-d, High-Dairy Cheese Diet Prevents Sodium-Induced Endothelial Dysfunction in the Cutaneous Microcirculation of Healthy, Older Adults through Reductions in Superoxide

BACKGROUND

While excess dietary sodium impairs vascular function by increasing oxidative stress, the dietary incorporation of dairy foods improves vascular health. We demonstrated that single-meal cheese consumption ameliorates acute, sodium-induced endothelial dysfunction. However, controlled feeding studies examining the inclusion of cheese, a dairy product that contains both bioactive constituents and sodium, are lacking.

OBJECTIVES

We tested the hypothesis that microcirculatory endothelium-dependent dilation (EDD) would be impaired by a high-sodium diet, but a sodium-matched diet high in dairy cheese would preserve EDD through oxidant stress mechanisms.

METHODS

We gave 11 adults without salt-sensitive blood pressure (<10 mmHg Δ mean arterial pressure; 64 ± 2 y) 4 separate 8-d controlled dietary interventions in a randomized, crossover design: a low-sodium, no-dairy intervention (LNa; 1500 mg/d sodium); a low-sodium, high-cheese intervention (LNaC; 1500 mg/d sodium, 170 g/d cheese); a high-sodium, no-dairy intervention (HNa; 5500 mg/d sodium); and a high-sodium, high-cheese intervention (HNaC; 5500 mg/d sodium, 170 g/d cheese). On Day 8 of each diet, EDD was assessed through a localized infusion (intradermal microdialysis) of acetylcholine (ACh), both alone and during coinfusion of NG-nitro-L-arginine methyl ester (NO synthase inhibitor), L-ascorbate (nonspecific antioxidant), apocynin [NAD(P)H oxidase inhibitor], or tempol (superoxide scavenger).

RESULTS

Compared with LNa, microvascular responsiveness to ACh was attenuated during HNa (LNa: -4.82 ± 0.20 versus HNa: -3.21 ± 0.55 M logEC50; P = 0.03) but not LNaC (-5.44 ± 0.20 M logEC50) or HNaC (-4.46 ± 0.50 M logEC50). Further, ascorbate, apocynin, and tempol administration each increased ACh-induced vasodilation during HNa only (Ringer's: 38.9 ± 2.4; ascorbate: 48.0 ± 2.5; tempol: 45.3 ± 2.7; apocynin: 48.5 ± 2.6% maximum cutaneous vascular conductance; all P values < 0.01).

CONCLUSIONS

These results demonstrate that incorporating dairy cheese into a high-sodium diet preserves EDD by decreasing the concentration of superoxide radicals. Consuming sodium in cheese, rather than in nondairy sources of sodium, may be an effective strategy to reduce cardiovascular disease risk in salt-insensitive, older adults. This trial was registered at clinicaltrials.gov as NCT03376555.

Effects of a High Fat Meal Associated with Water, Juice, or Champagne Consumption on Endothelial Function and Markers of Oxidative Stress and Inflammation in Young, Healthy Subjects

Endothelial dysfunction (ED), often linked to hypertriglyceridemia, is an early step of atherosclerosis. We investigated, in a randomized cross-over study, whether high-fat meal (HFM)-induced ED might be reduced by fruit juice or champagne containing polyphenols. Flow-mediated dilatation (FMD) and biological parameters (lipid profile, glycemia, inflammation, and oxidative stress markers) were determined before and two and three hours after the HFM in 17 healthy young subjects (24.6 ± 0.9 years) drinking water, juice, or champagne. Considering the entire group, despite significant hypertriglyceridemia (from 0.77 ± 0.07 to 1.41 ± 0.18 mmol/L, p < 0.001) and a decrease in Low Density Lipoprotein (LDL), the FMD was not impaired. However, the FMD decreased in 10 subjects (from 10.73 ± 0.95 to 8.13 ± 0.86 and 8.07 ± 1.16%; p < 0.05 and p < 0.01; 2 and 3 h, respectively, after the HFM), without concomitant change in concentration reactive protein or reactive oxygen species, but with an increase in glycemia. In the same subjects, the FMD did not decrease when drinking juice or champagne. In conclusion, HFM can impair the endothelial function in healthy young subjects. Fruit juice, rich in anthocyanins and procyanidins, or champagne, rich in simple phenolic acids, might reduce such alterations, but further studies are needed to determine the underlying mechanisms, likely involving polyphenols.

The influence of acute hyperglycaemia on brachial artery flow-mediated dilatation in the early and late follicular phases of the menstrual cycle

NEW FINDINGS

What is the central question of the study? This is the first study to examine the impact of acute hyperglycaemia on endothelial function [flow-mediated dilatation (FMD)] in premenopausal women across the early and late follicular (EF and LF) phases of the menstrual cycle. What is the main finding and its importance? Flow-mediated dilatation was impaired 90 min after glucose ingestion, with no significant difference between phases. This indicates that women are susceptible to acute hyperglycaemia-induced endothelial dysfunction in both the EF and LF phases of the menstrual cycle, despite potentially vasoprotective elevations in estradiol levels during the LF phase.

ABSTRACT

Acute hyperglycaemia transiently impairs endothelial function in healthy men when assessed via flow-mediated dilatation (FMD). However, research in female participants is lacking, and the impact of menstrual phase [early follicular (EF) and late follicular (LF)] on vulnerability to acute hyperglycaemia-induced endothelial dysfunction is unknown. Seventeen healthy, naturally menstruating women [21 ± 1 years old (mean ± SD)] participated in three visits. During two visits (EF_Glucose and LF_Glucose ), brachial artery FMD was assessed before and 60, 90 and 120 min after an oral glucose challenge (75 g glucose). During an additional EF visit, participants ingested 300 ml of water (EF_TimeControl ). Blood glucose and insulin increased 30 min after glucose ingestion (P < 0.001), with no difference between phases. Flow-mediated dilatation did not change in EF_TimeControl (P = 0.748) but was reduced 90 min after glucose ingestion (Pre, 8.5 ± 2.5%; Post90, 6.6 ± 2.4%, P = 0.001; Cohen's d = 0.82), with no difference between phases (main effect of phase, P = 0.506; phase by time interaction, P = 0.391). To account for individual variability in the time course of the impact of hyperglycaemia, the maximal hyperglycaemia-induced impairment in FMD was determined in each participant and compared between phases, revealing no significant phase differences (EF_Glucose , -3.1 ± 2.8%; LF_Glucose , -2.4 ± 2.1%, P = 0.181; d = 0.34). These results indicate that, similar to findings in men, acute hyperglycaemia results in FMD impairment in young women. We did not detect significant protection from acute hyperglycaemia-induced endothelial dysfunction in the LF 'high-oestrogen' phase in this sample, and further research is needed to examine the potential for a protective effect of oestrogen exposure, including oral contraceptive pills and hormone replacement therapy.

Effect of acarbose on cardiovascular events and new-onset diabetes in patients with coronary heart disease and impaired glucose tolerance

Many studies indicated postprandial hyperglycemia was closely related to the development of diabetes and the risk of cardiovascular disease. Acarbose was shown to delay the onset of diabetes in people with impaired glucose tolerance that was at low cardiovascular risk. The Acarbose Cardiovascular Evaluation (ACE) trial formally evaluated whether acarbose could reduce the frequency of cardiovascular events in patients with established coronary heart disease and impaired glucose tolerance, and whether the incidence of Type 2 diabetes could be reduced. The Acarbose Cardiovascular Evaluation trial represented that acarbose did not reduce the risk of Major Adverse Cardiovascular Events (MACE), but the risk of new-onset diabetes by 18% for a median of 5.0 years follow-up.

Short-Term Low-Carbohydrate High-Fat Diet in Healthy Young Males Renders the Endothelium Susceptible to Hyperglycemia-Induced Damage, An Exploratory Analysis

Postprandial hyperglycemia has been linked to elevated risk of cardiovascular disease. Endothelial dysfunction and/or damage may be one of the mechanisms through which this occurs. In this exploratory study, we determined whether acute glucose ingestion would increase markers of endothelial damage/activation and impair endothelial function before and after a short-term low-carbohydrate high-fat diet (HFD) designed to induce relative glucose intolerance. Nine healthy young males (body mass index 23.2 ± 2 kg/m²) consumed a 75 g glucose drink before and <24 hours after consuming seven days of an iso-energetic HFD consisting of ~70% energy from fat, ~10% energy from carbohydrates, and ~20% energy from protein. CD31+/CD42b- and CD62E+ endothelial microparticles (EMPs) were enumerated at fasting, 1 hour (1 h), and 2 hours (2 h) post-consumption of the glucose drink. Flow-mediated dilation (FMD), arterial stiffness, and diameter, velocity, and flow of the common and internal carotid, and vertebral arteries were assessed in the fasting state and 1 h post glucose consumption. After the HFD, CD31+/CD42b- EMPs were elevated at 1 h compared to 2 h (p = 0.037), with a tendency for an increase above fasting (p = 0.06) only post-HFD. CD62E EMPs followed the same pattern with increased concentration at 1 h compared to 2 h (p = 0.005) post-HFD, with a tendency to be increased above fasting levels (p = 0.078). FMD was reduced at 1 h post glucose consumption both pre- (p = 0.01) and post-HFD (p = 0.005). There was also a reduction in FMD in the fasting state following the HFD (p = 0.02). In conclusion, one week of low-carbohydrate high-fat feeding that leads to a relative impairment in glucose homeostasis in healthy young adults may predispose the endothelium to hyperglycemia-induced damage.

Effects of acute footbath before and after glucose ingestion on arterial stiffness

The present study investigated the acute effect of a footbath on increases in arterial stiffness after glucose ingestion in healthy young women. Nine healthy young women (aged 18.4 ± 0.2 years; mean ± SE) completed three trials in random order. They started a footbath before 75-g oral glucose ingestion, a footbath after 75-g oral glucose ingestion and no footbath (control) trials. Aortic (carotid-femoral) and leg (femoral-ankle) pulse wave velocity, the carotid augmentation index, carotid, brachial and ankle blood pressure, heart rate, blood glucose levels, insulin levels and sublingual temperature were measured before (baseline) and at 15, 30, 60 and 90 min after the 75-g oral glucose ingestion. Aortic pulse wave velocity and brachial systolic blood pressure did not change from baseline to after the 75-g oral glucose ingestion in all trials. Leg pulse wave velocity and ankle systolic blood pressure were increased from baseline to after the 75-g oral glucose ingestion in the footbath after glucose ingestion and control trials, but not in the footbath before glucose ingestion trial. These results suggest that a footbath effectively suppresses the increase in leg arterial stiffness after glucose ingestion when implemented before glucose ingestion.

An Overall Glance of Evidence Supportive of One-Hour and Two-Hour Postload Plasma Glucose Levels as Predictors of Long-Term Cardiovascular Events

This review summarizes the vast literature describing the long-term epidemiological studies with emphasis on postprandial glucose as a stronger predictor of cardiovascular complications as compared to fasting glucose and HbA1c. Many molecular studies also supported this fact by illustrating that postchallenge hyperglycemia is associated with elevated biomarkers of systemic inflammation in the plasma and thus increasing the chances of vascular damage. Large-scale studies have proved that vascular stiffness, brachial-ankle pulse-wave velocity, carotid intima thickness, and left ventricular hypertrophy have been associated with postprandial glucose as compared to fasting glucose or glycosylated hemoglobin.

Association between diet and measures of arterial stiffness in type 1 diabetes - Focus on dietary patterns and macronutrient substitutions

BACKGROUND AND AIMS

Increased arterial stiffness contributes to diabetic vascular complications. We identified dietary factors related to arterial stiffness in individuals with type 1 diabetes, a population with high risk of cardiovascular disease.

METHODS AND RESULTS

Altogether, 612 participants (40% men, mean ± standard deviation age 45 ± 13 years) completed a validated diet questionnaire and underwent measurements of arterial stiffness. Of these, 470 additionally completed a food record. Exploratory factor analysis was applied to identify dietary patterns from the diet questionnaires, and nutrient intakes were calculated from food record entries. Arterial stiffness was measured by applanation tonometry. Of the seven dietary factors formed, the factor scores of "Full-fat cheese and eggs" and "Sweet" patterns were negatively associated with measures of arterial stiffness. In the multivariable macronutrient substitution models, favouring carbohydrates over fats was associated with higher aortic mean arterial pressure and aortic pulse wave velocity. When carbohydrates were consumed in place of proteins, higher aortic pulse pressure, aortic mean arterial pressure, and augmentation index were recorded. Replacing energy from alcohol with proteins, was associated with lower aortic pulse pressure, aortic mean arterial pressure, and augmentation index. Relative distributions of dietary fatty acids were neutral with respect to the measures of arterial stiffness.

CONCLUSION

The macronutrient distribution of the diet is likely to affect the resilience of the arteries. Our observations suggest that reducing energy intake from carbohydrates and alcohol may be beneficial. These observations, especially those dealing with dietary patterns, need to be confirmed in a longitudinal study.

Dairy milk, regardless of fat content, protects against postprandial hyperglycemia-mediated impairments in vascular endothelial function in adults with prediabetes by limiting oxidative stress responses that reduce nitric oxide bioavailability

Postprandial hyperglycemia (PPH) transiently impairs vascular endothelial function (VEF) in an oxidative-stress-dependent manner by decreasing nitric oxide (NO^•) bioavailability. Dairy milk, regardless of fat content, attenuates PPH, but whether this improves VEF by limiting oxidative stress responses that otherwise decrease NO^• bioavailability is not known. We hypothesized that nonfat and full-fat dairy milk would similarly improve VEF by attenuating PPH-induced oxidative stress that otherwise decreases NO^• biosynthesis and bioavailability. A randomized, crossover trial was conducted in adults with prediabetes (n=22) who ingested glucose (75 g) dissolved in 473 ml of water (GLU), or glucose with an equal volume of nonfat dairy milk (NFM) or full-fat dairy milk (FFM). Prior to and at 30-min intervals for 180 min postprandially, we assessed brachial artery flow-mediated dilation (FMD) and measured circulating biomarkers of glycemic control, oxidative stress and NO^• homeostasis. AUC_{0-180 min} for FMD and NO^• metabolites was lowest in GLU but relatively greater in NFM and FFM. Compared with GLU, AUCs for glucose, malondialdehyde, F₂-isoprostanes and endothelin-1 were similarly lower in dairy trials. Milk-mediated vasoprotection was accompanied by greater levels of plasma arginine and lower levels of asymmetric dimethylarginine and symmetric dimethylarginine. Postprandial insulin, lipids and tetrahydrobiopterin redox status did not differ among trials. Thus, dairy milk, regardless of its fat content, attenuates PPH-mediated impairments in VEF by limiting oxidative stress. This improves NO^• bioavailability to the vascular endothelium by increasing arginine availability and limiting competitive inhibition on NO^• biosynthesis by asymmetric dimethylarginine.

t-Resveratrol Protects against Acute High Glucose Damage in Endothelial Cells

Postprandial hyperglycemia in diabetic and nondiabetic subjects is associated with endothelial dysfunction. Evidence shows that high glucose generates oxidative stress and a pro-inflammatory state promoting the development of cardiovascular diseases. trans-Resveratrol (t-RV) has been shown to reduce cardiovascular risk. To determine whether t-RV acts as a protector against acute high glucose (AHG)-induced damage, two in vitro models, rat aortic rings (RAR) and human umbilical vein endothelial cells (HUVEC) were used. RAR pretreated with AHG (25 mM D-glucose) for 3 h dramatically decreased the endothelium-dependent relaxation (EDR) induced by acetylcholine in phenylephrine (PE)-precontracted vessels. However, coincubation with t-RV significantly mitigated the damage induced by AHG on EDR. Pretreatment with AHG did not affect the vasodilation induced by sodium nitroprusside. HUVEC treated with t-RV decreased cytotoxicity and reduced radical oxygen species production induced by AHG. Taken together, these results suggest that t-RV can mitigate the AHG-induced EDR damage through a mechanism involving ROS scavenging and probably an increase in the bioavailability of NO.

Co-ingestion of whole eggs or egg whites with glucose protects against postprandial hyperglycaemia-induced oxidative stress and dysregulated arginine metabolism in association with improved vascular endothelial function in prediabetic men

Replacing a portion of a glucose challenge with whole eggs (EGG) or egg whites (WHITE) was shown to protect against glucose-induced impairments in vascular function. We hypothesised in the present study that previously observed vasoprotection following co-ingestion of EGG or WHITE with glucose was attributed to limiting postprandial hyperglycaemia-induced oxidative stress that improves NO∙ bioavailability. Prediabetic men completed a randomised, cross-over study in which they ingested isoenergetic meals containing 100 g glucose (GLU), or 75 g glucose with 1·5 EGG, seven WHITE or two egg yolks (YOLK). At 30 min intervals for 3 h, we assessed plasma NO∙ metabolites, the lipid peroxidation biomarker malondialdehyde, antioxidants, arginine and its methylated metabolites (asymmetric dimethylarginine and symmetric dimethylarginine), tetrahydrobiopterin redox status, vasoconstrictors and inflammatory markers. Compared with GLU, malondialdehyde was lower and NO∙ metabolites were greater in EGG and WHITE, but YOLK was not different from GLU. Malondialdehyde was inversely correlated with NO∙ metabolites and vascular function, whereas NO∙ metabolites were positively correlated with vascular function. Compared with GLU, arginine was greater, but asymmetric and symmetric dimethylarginine and angiotensin-II were lower in all egg-based meals. Antioxidants, tetrahydrobiopterin redox status and inflammatory markers did not differ among treatments. Thus, while each egg-based meal improved arginine metabolism, only EGG and WHITE limited lipid peroxidation. This suggests that vasoprotection mediated by EGG and WHITE likely occurs in an NO∙-dependent manner by improving arginine metabolism and attenuating oxidative stress that otherwise limit NO∙ biosynthesis and bioavailability to the vascular endothelium.

Comparative Metabolomics Elucidates Postprandial Metabolic Modifications in Plasma of Obese Individuals with Metabolic Syndrome

Although higher intakes of dairy milk are associated with a lower risk of metabolic syndrome (MetS), the underlying protective mechanism remains unclear. This study investigated the dynamic metabolic profile shift following the ingestion of low-fat milk or an isocaloric volume of rice milk in obese individuals with metabolic syndrome (MetS). In a randomized, double-blind, crossover study, postprandial plasma samples ( n = 266) were collected from 19 MetS participants. Plasma samples were analyzed by a targeted metabolomics platform which specifically detects 117 metabolites from 25 metabolic pathways. The comprehensive time-course metabolic profiling in MetS participants indicated that the postprandial metabolic profiles distinguish low-fat milk and rice milk consumption in a time-dependent manner. Metabolic biomarkers, such as orotate, leucine/isoleucine and adenine, showed significantly different trends in the two test beverages. Bayesian statistics identified 12 metabolites associated with clinical characteristics of postprandial vascular endothelial function, such as flow-mediated dilation (FMD), postprandial plasma markers of oxidative stress and NO status. Furthermore, metabolic pathway analysis based on these metabolite data indicated the potential utility of metabolomics to provide mechanistic insights of dietary interventions to regulate postprandial metabolic excursions.

Premeal Low-Fat Yogurt Consumption Reduces Postprandial Inflammation and Markers of Endotoxin Exposure in Healthy Premenopausal Women in a Randomized Controlled Trial

Background

Metabolic endotoxemia is associated with obesity and contributes to postprandial inflammation.

Objective

We aimed to determine if low-fat yogurt consumption prevents postprandial inflammation and dysmetabolism in healthy women by inhibiting biomarkers of metabolic endotoxemia.

Methods

Premenopausal women defined as obese and nonobese [body mass index (BMI, in kg/m2) 30-40 and 18.5-27, respectively, n = 120] were randomly assigned to consume 339 g of low-fat yogurt (YN, yogurt nonobese; YO, yogurt obese) or 324 g of soy pudding (CN, control nonobese; CO, control obese) for 9 wk (n = 30/group). The intervention foods each supplied 330 kcal with 3 g fat, 66 g carbohydrate, and 4-6 g protein. At weeks 0 and 9, participants ingested 226 g of yogurt or 216 g of soy pudding before a meal providing 56-60 g fat, 82 g carbohydrate, and 28-30 g protein. Plasma soluble CD14 (sCD14), lipopolysaccharide-binding protein (LBP), LPS activity, interleukin-6 (IL-6), glucose, triglyceride, and insulin were measured hourly for 4 h to assess differences in postprandial responses between groups by 2-factor ANOVA.

Results

Premeal yogurt consumption prevented the postprandial decrease in sCD14 net incremental area under the curve (net iAUC) by 72% in obese individuals at week 0 (P = 0.0323). YN and YO had ≥40% lower net iAUC of LBP-to-sCD14 ratio and plasma IL-6 concentration than CN and CO, respectively (P < 0.05). CO had postprandial hyperglycemia which was not evident in YO; in contrast YN had 57% less postprandial hypoglycemia than did CN (P-interaction = 0.0013). After 9 wk of yogurt consumption, ΔAUC of LBP-to-sCD14 ratios of YO and YN were less than half of those of the control groups (P = 0.0093).

Conclusion

Yogurt consumption improved postprandial metabolism and biomarkers of metabolic endotoxemia in healthy premenopausal women. Premeal yogurt consumption is a feasible strategy to inhibit postprandial dysmetabolism and thus may reduce cardiometabolic risk. This trial was registered at clinicaltrials.gov as NCT01686204.