Can postprandial blood glucose excursion be predicted in type 2 diabetes?

Valuation of the significant hypoglycemic activity of black currant anthocyanin extract by both starch structure transformation and glycosidase activity inhibition

The objective of this study was to investigate the impact of anthocyanin-rich black currant extract (BCE) on the structural properties of starch and the inhibition of glycosidases, gathering data and research evidence to support the use of low glycemic index (GI) foods. The BCE induced a change in the starch crystal structure from A-type to V-type, resulting in a drop in digestibility from 81.41 % to 65.57 %. Furthermore, the inhibitory effects of BCE on glycosidases activity (α-glucosidase: IC50 = 0.13 ± 0.05 mg/mL and α-amylase: IC50 = 2.67 ± 0.16 mg/mL) by inducing a change in spatial conformation were confirmed through in vitro analysis. The presence of a 5'-OH group facilitated the interaction between anthocyanins and receptors of amylose, α-amylase, and α-glucosidase. The glycosyl moiety enhanced the affinity for amylose yet lowered the inhibitory effect on α-amylase. The in vivo analysis demonstrated that BCE resulted in a reduction of 3.96 mM·h in blood glucose levels (Area Under Curve). The significant hypoglycemic activity, particularly the decrease in postprandial blood glucose levels, highlights the potential of utilizing BCE in functional foods for preventing diabetes.

Functional insulin aspart/insulin degludec-based microneedles for promoting postprandial glycemic control

Insulin aspart (IAsp) and insulin degludec (IDeg), as the third generation of insulin, have a faster onset time or a more durable action period, which may simulate the secretion of insulin under physiological conditions. Microneedles (MNs) are transdermal delivery devices that may allow diabetic patients to easily deploy transdermal insulin therapy while considerably reducing injection pain. In this study, we investigated the combination of dissolving MNs with IAsp or IDeg therapy as an alternative to daily multiple insulin injections, aiming to improve glycemic control and patient compliance. Mechanical properties of the MNs, structural stability of insulin encapsulated in the MNs, and transdermal application characteristics were studied to assess the practicality of insulin-loaded MNs for diabetes therapy. In vivo experiments conducted on diabetic rats demonstrated that the IAsp- and IDeg-loaded MNs have comparable blood glucose control abilities to that of subcutaneous injections. In addition, the therapeutic properties of insulin-loaded MNs under diverse dietary conditions and application strategies were further investigated to provide new information to support future clinical trials. Taken together, the proposed MNs have the potential to improve balances between glycemic control, hypoglycemia risk, and convenience, providing patients with simpler regimens. STATEMENT OF SIGNIFICANCE: 1. The fabricated functional insulin-loaded dissolving microneedles closely matched the glucose rise that occurs in response to meals, demonstrating promising alternatives for multiple daily insulin injections. 2. The hypoglycemic properties of insulin microneedles were investigated under diverse dietary conditions and application strategies, yielding new information to support future clinical trials. 3. Molecular dynamics simulations were utilized to study the interactions between the insulin and microneedle matrix materials, providing a strategy for theoretically understanding drug stability as well as the release mechanism of drug-loaded microneedles.

Impact of a low-carbohydrate versus low-fat breakfast on blood glucose control in type 2 diabetes: a randomized trial

BACKGROUND

In type 2 diabetes (T2D), consuming carbohydrates results in a rapid and large increase in blood glucose, particularly in the morning when glucose intolerance is highest.

OBJECTIVE

We investigated if a low-carbohydrate (LC) breakfast (∼465kcal: 25g protein, 8g carbohydrates, 37g fat) could improve glucose control in people with type 2 diabetes when compared to a low-fat control (CTL) breakfast (∼450kcal:20g protein, 56g carbohydrates, 15g fat).

METHODS

Participants with T2D (N=121, 53% female, mean age 64 years) completed a remote 3-month parallel-group randomized controlled trial comparing a LC versus standard low-fat guideline CTL breakfast. Change in hemoglobin A1c (HbA1c) was the pre-specified primary outcome. Continuous glucose monitoring, self-reported anthropometrics and dietary information were collected for an intention-to-treat analysis.

RESULTS

HbA_1c was reduced (-0.3%, 95% CI: -0.4% to -0.1%) after 12 weeks of a LC breakfast, but the between group difference in HbA_1c was of borderline statistical significance (-0.2, 95% CI: -0.4 to 0.0; P=0.06). Self-reported total daily energy (-242 kcal, 95% CI -460 to -24 kcal; P=0.03) and carbohydrate (-73g, 95% CI: -101 to -44 g; P<0.01) intake were lower in the LC group but the significance of this difference is unclear. Mean and maximum glucose, area under the curve, glycemic variability, standard deviation, and time above range were all significantly lower, and time in range was significantly higher, in the LC group compared to CTL (all P<0.05).

CONCLUSIONS

Advice and guidance to consume a LC breakfast appears to be a simple dietary strategy to reduce overall energy and carbohydrate intake and improve several CGM variables when compared to a CTL breakfast in persons living with T2D.

TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT04550468.

Effect of diabetes-specific oral nutritional supplements with allulose on weight and glycemic profiles in overweight or obese type 2 diabetic patients

BACKGROUND/OBJECTIVES

Diabetes-specific oral nutritional supplements (ONS) have anti-hyperglycemic effects, while D-allulose exerts anti-diabetic and anti-obesity effects. In this study, we investigated the efficacy and safety of diabetes-specific ONS, including allulose, on glycemic and weight changes in overweight or obese patients with type 2 diabetes mellitus (T2DM).

SUBJECTS/METHODS

A single-arm, historical-control pilot clinical trial was conducted on 26 overweight or obese patients with T2DM (age range: 30-70 yrs). The participants were administered 2 packs of diabetes-specific ONS, including allulose (200 kcal/200 mL), every morning for 8 weeks. The glycemic profiles, obesity-related parameters, and lipid profiles were assessed to evaluate the efficacy of ONS.

RESULTS

After 8 weeks, fasting blood glucose (FBG) level significantly decreased from 139.00 ± 29.66 mg/dL to 126.08 ± 32.00 mg/dL (P = 0.007) and glycosylated hemoglobin (HbA1c) improved (7.23 ± 0.82% vs. 7.03 ± 0.69%, P = 0.041). Moreover, the fasting insulin (δ: -1.81 ± 3.61 μU/mL, P = 0.017) and homeostasis model assessment for insulin resistance (HOMA-IR) (δ: -0.87 ± 1.57, P = 0.009) levels decreased at 8 weeks, and body weight significantly decreased from 67.20 ± 8.29 kg to 66.43 ± 8.12 kg (P = 0.008). Body mass index (BMI) also decreased in accordance with this (from 25.59 ± 1.82 kg/m2 to 25.30 ± 1.86 kg/m2, P = 0.009), as did waist circumference (δ: -1.31 ± 2.04 cm, P = 0.003).

CONCLUSIONS

The consumption of diabetes-specific ONS with allulose in overweight or obese patients with T2DM improved glycemic profiles, such as FBG, HbA1c, and HOMA-IR, and reduced body weight and BMI.

Novel trends and concepts in the nutritional management of glycemia in type 2 diabetes mellitus-beyond dietary patterns: a narrative review

A variety of eating patterns are recommended by international guidelines to help people with type 2 diabetes mellitus (T2DM) achieve general health and glycemia goals. Apart from eating patterns, there is evidence that other approaches related to the everyday application of dietary advice, such as meal frequency, breakfast consumption, daily carbohydrate distribution, and order of food consumption during meals, have significant effects on glycemia management. The aims of this review were to examine published diabetes nutrition guidelines concerning specific recommendations with regard to the above approaches, as well as to review evidence from studies that have investigated their effect on glycemia in T2DM. The data suggest that eating breakfast regularly, consuming most carbohydrates at lunch, avoiding large dinners late at night, and applying the carbohydrate-last meal pattern are effective practices towards better nutritional management of T2DM.

Enlarged glycemic variability in sulfonylurea-treated well-controlled type 2 diabetics identified using continuous glucose monitoring

Time in range (TIR) is an index of glycemic control obtained from continuous glucose monitoring (CGM). The aim was to compare the glycemic variability of treatment with sulfonylureas (SUs) in type 2 diabetes mellitus (T2DM) with well-controlled glucose level (TIR > 70%). The study subjects were 123 patients selected T2DM who underwent CGM more than 24 h on admission without changing treatment. The primary endpoint was the difference in glycemic variability, while the secondary endpoint was the difference in time below range < 54 mg/dL; TBR < 54, between the SU (n = 63) and non-SU (n = 60) groups. The standard deviation, percentage coefficient of variation (%CV), and maximum glucose level were higher in the SU group than in the non-SU group, and TBR < 54 was longer in the high-dose SU patients. SU treatment was identified as a significant factor that affected %CV (β: 2.678, p = 0.034). High-dose SU use contributed to prolonged TBR < 54 (β: 0.487, p = 0.028). Our study identified enlarged glycemic variability in sulfonylurea-treated well-controlled T2DM patients and high-dose SU use was associated with TBR < 54. The results highlight the need for careful adjustment of the SU dose, irrespective of glycated hemoglobin level or TIR value.

A basal-bolus insulin regimen integrated microneedle patch for intraday postprandial glucose control

Multiple daily insulin injections have been a common regimen worldwide for the management of diabetes mellitus but involved potential safety and compliance problems. In this context, a single integrated microneedle patch (IMP) with multiple release kinetics is demonstrated to provide better physiologic insulin coverage for postprandial glycemic excursion in a convenient and pain-free manner. The combination of rapid separating technique and multiple individual microneedle arrays provides the combined ability to efficiently deliver insulin into the skin within seconds and to independently control insulin release kinetics. In addition, the diabetic rats with a traditional breakfast-lunch-dinner lifestyle exhibit obvious intraday glucose fluctuations, while the hypoglycemic experiments indicate that the IMP is capable of simultaneous bolus and sustained insulin delivery to closely match the glucose rise that occurs in response to meals and efficiently minimize excessive fluctuations, suggesting the potential of this new transdermal insulin delivery system as substitutes for multiple daily injections.

Restricting carbohydrates at breakfast is sufficient to reduce 24-hour exposure to postprandial hyperglycemia and improve glycemic variability

BACKGROUND

The breakfast meal often results in the largest postprandial hyperglycemic excursion in people with type 2 diabetes.

OBJECTIVE

Our purpose was to investigate whether restricting carbohydrates at breakfast would be a simple and feasible strategy to reduce daily exposure to postprandial hyperglycemia.

DESIGN

Adults with physician-diagnosed type 2 diabetes [n = 23; mean ± SD age: 59 ± 11 y; glycated hemoglobin: 6.7% ± 0.6%; body mass index (kg/m2): 31 ± 7] completed two 24-h isocaloric intervention periods in a random order. Participants consumed one of the following breakfasts: 1) a very-low-carbohydrate high-fat breakfast (LCBF; <10% of energy from carbohydrate, 85% of energy from fat, 15% of energy from protein) or 2) a breakfast with dietary guidelines-recommended nutrient profile (GLBF; 55% of energy from carbohydrate, 30% of energy from fat, 15% of energy from protein), with the same lunch and dinner provided. Continuous glucose monitoring was used to assess postprandial glucose responses over 24 h, and visual analog scales were used to assess ratings of hunger and fullness.

RESULTS

The LCBF significantly reduced postprandial hyperglycemia after breakfast (P < 0.01) and did not adversely affect glycemia after lunch or dinner. As such, overall postprandial hyperglycemia (24-h incremental area under the glucose curve) and glycemic variability (mean amplitude of glycemic excursions) were reduced with the LCBF (24-h incremental area under the glucose curve: -173 ± 361 mmol/L; P = 0.03; mean amplitude of glycemic excursions: -0.4 ± 0.8 mmol/L · 24 h; P = 0.03) compared with the GLBF. Premeal hunger was lower before dinner with the LCBF than with the GLBF (P-interaction = 0.03).

CONCLUSIONS

A very-low-carbohydrate high-fat breakfast lowers postbreakfast glucose excursions. The effects of this simple strategy appear to be sufficient to lower overall exposure to postprandial hyperglycemia and improve glycemic variability. Longer-term interventions are warranted. This trial was registered at clinicaltrials.gov as NCT02982330.

Association of lower body mass index with increased glycemic variability in patients with newly diagnosed type 2 diabetes: a cross-sectional study in China

Previous studies have indicated that the pathogenesis of diabetes differs between obese and lean patients. We investigated whether newly diagnosed Chinese diabetic patients with different body mass indices (BMIs) have different glycemic variability, and we assessed the relationship between BMI and glycemic variability. This was a cross-sectional study that included 169 newly diagnosed and drug-naïve type 2 diabetic patients (mean age, 51.33 ± 9.83 years; 110 men). The clinical factors and results of the 75-g oral glucose tolerance test were all recorded. Glycemic variability was assessed using continuous glucose monitoring. Compared with overweight or obese patients (BMI ≥ 24 kg/m2), underweight or normal-weight patients (BMI < 24 kg/m2) had higher levels of blood glucose fluctuation parameters, particularly in terms of mean amplitude of glycemic excursion (MAGE 6.64 ± 2.38 vs. 5.67 ± 2.05; P = 0.007) and postprandial glucose excursions (PPGEs) (PPGE at breakfast, 7.72 ± 2.79 vs. 6.79 ± 2.40, P = 0.028; PPGE at lunch, 5.53 ± 2.70 vs. 5.07 ± 2.40, P = 0.285; PPGE at dinner, 5.96 ± 2.24 vs. 4.87 ± 2.50, P = 0.008). BMI was negatively correlated with glycemic variability (r = −0.243, P = 0.002). On multiple linear regression analyses, BMI (β = −0.231, P = 0.013) and Insulin Secretion Sensitivity Index-2 (β = −0.204, P = 0.048) were two independent predictors of glycemic variability. In conclusion, lower BMI was associated with increased glycemic variability, characterized by elevated PPGEs, in newly diagnosed Chinese type 2 diabetic patients.

Effects of Higher Dietary Protein and Fiber Intakes at Breakfast on Postprandial Glucose, Insulin, and 24-h Interstitial Glucose in Overweight Adults

Dietary protein and fiber independently influence insulin-mediated glucose control. However, potential additive effects are not well-known. Men and women (n = 20; age: 26 ± 5 years; body mass index: 26.1 ± 0.2 kg/m²; mean ± standard deviation) consumed normal protein and fiber (NPNF; NP = 12.5 g, NF = 2 g), normal protein and high fiber (NPHF; NP = 12.5 g, HF = 8 g), high protein and normal fiber (HPNF; HP = 25 g, NF = 2 g), or high protein and fiber (HPHF; HP = 25 g, HF = 8 g) breakfast treatments during four 2-week interventions in a randomized crossover fashion. On the last day of each intervention, meal tolerance tests were completed to assess postprandial (every 60 min for 240 min) serum glucose and insulin concentrations. Continuous glucose monitoring was used to measure 24-h interstitial glucose during five days of the second week of each intervention. Repeated-measures ANOVA was applied for data analyses. The HPHF treatment did not affect postprandial glucose and insulin responses or 24-h glucose total area under the curve (AUC). Higher fiber intake reduced 240-min insulin AUC. Doubling the amount of protein from 12.5 g to 25 g/meal and quadrupling fiber from 2 to 8 g/meal at breakfast was not an effective strategy for modulating insulin-mediated glucose responses in these young, overweight adults.

Diabetes and chocolate: friend or foe?

Polyphenols and other compounds found in cocoa and chocolate have therapeutic potential in the management of diabetes in humans. Polyphenol benefits have been proposed supported by in vitro studies, animal work, and clinical trials, which have been conducted mostly in healthy volunteers. The energy-dense formulations of many cocoa and chocolate products, which can be up to 50% sugar by weight, have given the perception that chocolate may be harmful through its contribution to obesity. A review of both clinical trial databases and published literature yielded 15 registered trials and 7 published studies. The published data interventions reported are diverse and vary widely in quality, including poor selection of control products or inadequate blinding procedures. There are also inconsistencies in reporting of data with limited information on the effect of cocoa and chocolate supplementation on weight and glycemic control despite the potential benefits reported with respect to the cardiovascular risk factors of endothelial function and lipids. More studies are required powered for primary clinical outcomes together with the development of standardized product formulations that optimize the dose of polyphenols within a palatable and energy-restricted product.

Patterns of postprandial hyperglycemia after basal insulin therapy: individual and regional differences

BACKGROUND

Treatment of postprandial hyperglycemia could be needed when basal insulin added to oral therapy does not maintain glycated haemoglobin (HbA1C ) targets in type 2 diabetes mellitus. Knowing individual and regional patterns of postprandial hyperglycemia in this setting might improve therapeutic decisions.

METHODS

Patient-level self-monitored blood glucose data were pooled from six studies of insulin glargine for patients with HbA1C  ≥ 7.0% after 24 weeks. Percentages of participants with highest daily postprandial blood glucose and greatest postprandial increments after each of the three daily meals were calculated and compared between four geographical regions; USA, Canada, Germany, and other European countries.

RESULTS

For 494 participants (mean age 60.1 years, diabetes duration 9.6 years, and BMI 29.8 kg/m(2) ), mean endpoint HbA1C was 7.8%. On insulin glargine treatment, highest postprandial blood glucose most often occurred post-dinner (44% of participants) and greatest postprandial increments post-breakfast (46% of participants) in all regions. Participants with greatest postprandial increments post-breakfast were older and experienced less HbA1C improvement with insulin glargine than those with greatest postprandial increments after other meals. Post-breakfast and post-dinner postprandial blood glucose was higher in the USA and Canada versus Germany, and in the USA versus Other European countries (all p < 0.05). Postprandial increments after dinner were greater in the USA versus all other regions.

CONCLUSIONS

Generally, highest postprandial blood glucose follows dinner and greatest postprandial increments follow breakfast. Variations in patient characteristics and eating patterns might underlie differences both within and between regions. Awareness of regional differences and evaluation of an individual's typical eating pattern might facilitate appropriate prandial therapy.

Equal improvement in glycaemia with lixisenatide given before breakfast or the main meal of the day

AIMS

The aim of this study is to explore whether administration timing affects glycaemic control by lixisenatide once-daily in type 2 diabetes mellitus (T2DM).

METHODS

A phase IIIb, open-label, 1:1 randomized, active-controlled, 24-week multicentre study of T2DM patients inadequately controlled on metformin was conducted. Patients were administered lixisenatide before breakfast or the main meal. The primary endpoint was change from baseline at week 24 in glycated haemoglobin (HbA1c). Other endpoints: changes in body weight, fasting plasma glucose (FPG), 7-point self-monitored plasma glucose (SMPG) and Diabetes Treatment Satisfaction Questionnaire status (DTSQs) score. Adverse events (AEs) were monitored.

RESULTS

Mean change in HbA1c from baseline at week 24 was -0.65% (-7.1mmol/mol; main meal) and -0.74% (-8.1mmol/mol; breakfast). Mean changes in FPG, body weight and DTSQs score were comparable between groups. The mean change in body weight (kg) was -2.60 (main meal) and -2.80 (breakfast group). The 7-point SMPG profiles showed greatest reductions in postprandial glucose after the meal at which lixisenatide was administered, with a residual effect seen on the subsequent meal. AE rates were similar between groups, including gastrointestinal AEs.

CONCLUSIONS

Lixisenatide before the main meal was noninferior to lixisenatide before breakfast in patients insufficiently controlled on metformin. Lixisenatide treatment allows flexibility in administration timing.

Glycemic index predicts individual glucose responses after self-selected breakfasts in free-living, abdominally obese adults

The degree to which an individual's glycemic response to a meal is determined by the glycemic index (GI) and other components of the meal remains unclear, especially when meals are not consumed in a highly controlled research setting. To address this question, we analyzed data collected during the run-in period of a clinical trial. Free-living, nondiabetic adults (n = 57) aged 53.9 ± 9.8 y (mean ± SD) with a BMI of 33.9 ± 5.3 kg/m(2) and waist circumference of 109 ± 11 cm underwent a 75-g oral glucose tolerance test (OGTT) and, on a separate day, wore a continuous glucose-monitoring system (CGMS) for 24 h during which time they recorded all foods consumed. The protein, fat, and available carbohydrate (avCHO) content and GI of the breakfast meals were calculated from the food records and the incremental areas under the glycemic response curves (iAUC) for 2 h after breakfast (iAUC(breakfast)) were calculated from CGMS data. Values for iAUC(breakfast), avCHO, fat, fiber, and BMI were normalized by log-transformation. The ability of participant characteristics and breakfast composition to predict individual iAUC(breakfast) responses was determined using step-wise multiple linear regression. A total of 56% of the variation in iAUC(breakfast) was explained by GI (30%; P < 0.001), iAUC after the OGTT (11%; P < 0.001), avCHO (11%; P < 0.001), and waist circumference (3%; P = 0.049); the effects of fat, protein, dietary fiber, age, sex, and BMI were not significant. We concluded that, in free-living, abdominally obese adults, GI is a significant determinant of individual glycemic responses elicited by self-selected breakfast meals. In this study, GI was a more important determinant of glycemic response than carbohydrate intake.