Are New Ultra-Rapid-Acting Insulins Associated with Improved Glycemic Control and Reduced Hypoglycemia in Comparison to Conventional Rapid-Acting Insulins for Individuals with Type 1 and Type 2 Diabetes? A Systematic Review and Meta-Analysis

Introduction: This study aimed to compare efficacy and safety of ultra-rapid-acting insulin analogs (URAIs; faster aspart [FAsp], ultra-rapid lispro [URLi], and technosphere insulin [TI]) with rapid-acting insulin analogs (RAI) in individuals with type 1 (T1D) or type 2 diabetes (T2D). Methods: Searching for randomized control trial comparing the effects of URAI versus RAI that lasted at least 12 weeks, we initially selected 15 studies for analysis. Three studies involving TI were excluded due to a high degree of heterogeneity. The final meta-analysis included only 12 studies with either FAsp or URLi. Results: Mealtime URAI significantly reduced overall early 1 h postprandial glycemia in individuals with T1D (-20.230 mg/dL [95% confidence interval, 95% CI -24.040 to -16.421]; P < 0.001; I2 = 33.42%) and those with T2D (-9.138 mg/dL [95% CI -12.612 to -5.663]; P < 0.001; I2 = 0%). However, the significant reduction in 2 h postprandial glucose remained only in individuals with T1D (-17.620 mg/dL [95% CI -26.047 to -9.193]; P < 0.001; I2 = 65.88%). These benefits were lost when URAI was administered postmeal. At 24-26 weeks, there was no significant difference in HbA1c between groups, but at 52 weeks, a slight reduction in HbA1c with mealtime URAI was observed (-0.080% [95% CI -0.147 to -0.013]; P = 0.019; I2 = 0%). No difference in weight or the rate of severe or confirmed hypoglycemia was observed. Only individuals with T1D showed a small, but significant increase in early 1-h hypoglycemia with URAI (1.468 [95% CI 1.235 to 1.747]; P < 0.001; I2 = 0%). Conclusion: Mealtime URAI improves 1 and 2 h postprandial glycemic control compared to RAI without increasing hypoglycemia or weight gain.

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.

Ultrarapid Insulin Use Can Reduce Postprandial Hyperglycemia and Late Hypoglycemia, Even in Delayed Insulin Injections: A Connected Insulin Cap-Based Real-World Study

Objectives: Reaching optimal postprandial glucose dynamics is a daily challenge for people with type 1 diabetes (T1D). This study aimed to analyze the postprandial hyperglycemic excursion (PHEs) and late postprandial hypoglycemia (LPH) risk according to prandial insulin time and type. Research Design and Methods: Real-world, retrospective study in T1D using multiple daily injections (MDI) analyzing 5 h of paired continuous glucose monitoring and insulin injections data collected from the connected cap Insulclock®. Meal events were identified using the rate of change detection methodology. Postprandial glucometrics and LPH (glucose <70 mg/dL 2-5 h after a meal) were evaluated according to insulin injection time and rapid (RI) or ultrarapid analog, Fiasp® (URI), use. Results: Meal glycemic excursions (n = 2488), RI: 1211, 48.7%; UR: 1277, 51.3%, in 82 people were analyzed according to injection time around the PHE: -45 to -15 min; -15 to 0 min; and 0 to +45 min. In 63% of the meals, insulin was injected after the PHE started. Lower PHE was observed with URI versus RI (glucose peak-baseline; mg/dL; mean ± standard deviation): 106.7 ± 35.2 versus 111.2 ± 40.3 (P = 0.003), particularly in 0/+45 injections: 111.6 ± 40.2 versus 118.1 ± 43.3; (P = 0.002). One third (29.1%) of participants added a second (correction) injection. The use of URI and avoiding a second injection were independently associated with less LPH risk, even in delayed injections (0/+45), (-36%, odds ratio [OR] 0.641; confidence interval [CI]: 0.462-0.909; P = 0.012) and -56% (OR 0.641; CI: 0.462-0.909 P = 0.038), respectively. Conclusions: URI analog use as prandial insulin reduces postprandial hyper- and hypoglycemia, even in delayed injections.

Pre-Meal Whey Protein Alters Postprandial Insulinemia by Enhancing β-Cell Function and Reducing Insulin Clearance in T2D

CONTEXT

Treatments that reduce postprandial glycemia (PPG) independent of stimulating insulin secretion are appealing for the management of type 2 diabetes (T2D). Consuming pre-meal whey protein (WP) reduces PPG by delaying gastric emptying and increasing plasma insulin concentrations. However, its effects on β-cell function and insulin kinetics remains unclear.

OBJECTIVE

To examine the PPG-regulatory effects of pre-meal WP by modeling insulin secretion rates (ISR), insulin clearance, and β-cell function.

METHODS

This was a single-blind, randomized, placebo-controlled, crossover design study in 18 adults with T2D (HbA1c, 56.7 ± 8.8 mmol/mol) who underwent 2 240-minute mixed-meal tolerance tests. Participants consumed WP (15 g protein) or placebo (0 g protein) 10 minutes before a mixed-macronutrient breakfast meal. PPG, pancreatic islet, and incretin hormones were measured throughout. ISR was calculated by C-peptide deconvolution. Estimates of insulin clearance and β-cell function were modeled from glucose, insulin, and ISR. Changes in PPG incremental area under the curve (iAUC; prespecified) and insulin clearance (post hoc) were measured.

RESULTS

β-cell function was 40% greater after WP (P = .001) and was accompanied with a -22% reduction in postprandial insulin clearance vs placebo (P < .0001). Both the peak change and PPG iAUC were reduced by WP (-1.5 mmol/L and -16%, respectively; both P < .05). Pre-meal WP augmented a 5.9-fold increase in glucagon and glucagon-like peptide 1 iAUC (both P < .0001), and a 1.5-fold increase in insulin iAUC (P < .001). Although the plasma insulin response was greater following WP, ISR was unaffected (P = .133).

CONCLUSION

In adults with T2D, pre-meal WP reduced PPG by coordinating an enhancement in β-cell function with a reduction in insulin clearance. This enabled an efficient postprandial insulinemic profile to be achieved without requiring further β-cell stimulation.Trial registry ISRCTN ID: ISRCTN17563146 Website link: www.isrctn.com/ISRCTN17563146.

Long-term effects of lowering postprandial glucose level on cardiovascular outcomes in early-stage diabetic patients with coronary artery disease: 10-year post-trial follow-up analysis of the DIANA study

AIMS

To elucidate the long-term cardiovascular benefit of lowering postprandial hyperglycemia (PPG) in early-stage T2DM patients.

METHODS

This 10-year post-trial follow-up study included 243 patients from the DIANA (DIAbetes and diffuse coronary Narrowing) study, a multi-center randomized controlled trial which compared the efficacy of one-year life-style and pharmacological (voglibose/nateglinide) intervention lowering PPG on coronary atherosclerosis in 302 early-stage T2DM subjects [impaired glucose tolerance (IGT) or newly-diagnosed T2DM] (UMIN-CTRID#0000107). MACE (all-cause death, non-fatal MI or unplanned coronary revascularization) were compared in (1) three assigned therapies (life-style intervention/vogliose/nateglinide) and (2) patients with and without improvement of PPG (reversion from IGT to NGT or from DM to IGT/NGT on 75 g oral glucose tolerance test).

RESULTS

During the 10-year post-trial observational period, voglibose (HR = 1.07, 95%CI: 0.69-1.66, p = 0.74) or nateglinide (HR = 0.99, 95%CI: 0.64-1.55, p = 0.99) did not reduce MACE. Similarly, achieving the improvement of PPG was not associated with a reduction of MACE (HR = 0.78, 95%CI: 0.51-1.18, p = 0.25). However, in IGT subjects (n = 143), this glycemic management significantly reduced the occurrence of MACE (HR = 0.44, 95%CI: 0.23-0.86, p = 0.01), especially unplanned coronary revascularization (HR = 0.46, 95%CI: 0.22-0.94, p = 0.03).

CONCLUSIONS

The early improvement of PPG significantly reduced MACE and unplanned coronary revascularization in IGT subjects during the post-trial 10-year period.

Protein intake and postprandial hyperglycemia in children and adolescents with type 1 diabetes mellitus, a pilot study

BACKGROUND AND AIMS

To describe the change in glucose and the resulting postprandial hyperglycemia (PPH) that occurs after dietary protein intake (PI) in children with type 1 diabetes (T1D).

METHODS

We conducted a self-controlled, non-randomized, prospective pilot study in children with T1D who were given whey protein isolate drinks (carbohydrate-free, fat-free) of increasing protein amounts (0, 12.5, 25, 37.5, 50, and 62.5 gm) on 6 sequential nights. The glucose levels were monitored with continuous glucose monitors (CGM) and glucometers for 5 h after PI. PPH was defined as glucose elevations over baseline of ≥50 mg/dL.

RESULTS

Thirty-eight subjects were recruited, and eleven subjects (6 females, 5 males) completed the intervention. Subjects had a mean (range) age of 11.6 (6-16) years, diabetes duration of 6.1 (1.4-15.5) years, HbA1c of 7.2 (5.2-8.6) % and weight of 44.5 (24.3-63.2) kg. PPH was detected in 1/11, 5/11, 6/10, 6/9, 5/9, and 8/9 subjects after receiving 0, 12.5, 25, 37.5, 50, and 62.5 gm of protein, respectively.

CONCLUSIONS

In children with T1D, the association between PPH and PI was observed at smaller protein amounts compared to studies done in adults.

The effect of fermented rice germ extracts on the inhibition of glucose uptake in the gastrointestinal tract in vitro and in vivo

This study aimed to evaluate the effect of fermented rice germ extracts on the inhibition of glucose uptake in the gastrointestinal (GI) tract. Samples were prepared by extracting rice germ fermented with Lactobacillus plantarum with 30% ethanol (RG_30E) or 50% ethanol (RG_50E). Ferulic acid was determined as the active component in the samples. RG_30E significantly inhibited glucose uptake and mRNA expression of GLUT2 and SGLT1 to a larger extent than RG_50E in Caco-2 cells. A single oral administration was performed on C57BL/6 mice to confirm which substrate (glucose, sucrose, or maltose) the sample inhibited absorption of, improving postprandial blood glucose elevation. As a result, RG_30E resulted in significantly lower blood glucose levels and AUC after glucose and sucrose administration. Therefore, fermented rice germ extracted with 30% ethanol regulates glucose uptake through glucose transporters and can be expected to alleviate postprandial hyperglycemia in the GI tract.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01198-6.

Super Bolus: a remedy for a high glycemic index meal in children with type 1 diabetes on insulin pump therapy?-study protocol for a randomized controlled trial

Background

Postprandial hyperglycemia (PPH) is a common clinical problem among patients with type 1 diabetes (T1D), which is related to high glycemic index (h-GI) meals. The main problem is linked to high, sharp glycemic spikes following hypoglycemia after h-GI meal consumption. There is a lack of effective and satisfactory solutions for insulin dose adjustment to cover an h-GI meal. The goal of this research was to determine whether a Super Bolus is an effective strategy to prevent PPH and late hypoglycemia after an h-GI meal compared to a Normal Bolus.

Methods

A total of 72 children aged 10–18 years with T1D for at least 1 year and treated with continuous subcutaneous insulin infusion for more than 3 months will be enrolled in a double-blind, randomized, crossover clinical trial. The participants will eat a h-GI breakfast for the two following days and receive a prandial insulin bolus in the form of a Super Bolus 1 day and a Normal Bolus the next day. The glucose level 90 min after the administration of the prandial bolus will be the primary outcome measure. The secondary endpoints will refer to the glucose levels at 30, 60, 120, 150, and 180 min postprandially, the area under the blood glucose curve within 180 min postprandially, peak glucose level and the time to peak glucose level, glycemic rise, the mean amplitude of glycemic excursions, and the number of hypoglycemia episodes.

Discussion

There are still few known clinical studies on this type of bolus. A Super Bolus is defined as a 50% increase in prandial insulin dose compared to the dose calculated based on the individualized patient’s insulin-carbohydrate ratio and a simultaneous suspension of basal insulin for 2 h. Our patients reported the best experience with such a combination. A comprehensive and effective solution to this frequent clinical difficulty of PPH after an h-GI meal has not yet been found. The problem is known and important, and the presented solution is innovative and easy to apply in everyday life.

Trial registration

ClinicalTrials.gov NCT04019821

Low fasting glucose-to-estimated average glucose ratio was associated with superior response to insulin degludec/aspart compared with basal insulin in patients with type 2 diabetes

AIMS/INTRODUCTION

The benefits of once-daily insulin degludec/aspart (IDegAsp) compared with basal insulin in type 2 diabetes patients have not been established.

MATERIALS AND METHODS

This was a retrospective observational study. From a basal insulin cohort from three referral hospitals, patients were enrolled who initiated once-daily IDegAsp. A control group maintaining basal insulin was selected by propensity score matching. Glycated hemoglobin (HbA1c) changes over a period of 6 months and associated clinical factors were evaluated.

RESULTS

The IDegAsp group and the control group comprised of 87 patients, respectively. Baseline HbA1c was comparable between the two groups (8.7 ± 0.9 vs 8.6 ± 0.9%, mean and standard deviation). After 6 months with matched insulin doses, HbA1c in the IDegAsp group was lower than that in the control group (8.1 ± 1.0 vs 8.4 ± 1.1%, P = 0.029). Among baseline variables, fasting plasma glucose (FPG) and fasting C-peptide in the IDegAsp were lower than that in the control (FPG 124.2 ± 38.4 vs 148.0 ± 50.6 mg/dL, P < 0.001). Considering that the lower FPG despite the comparable HbA1c could be related with the efficacy of IDegAsp, subgroup analysis was carried out according to a ratio of FPG-to-estimated average glucose, which is calculated from HbA1c. When compared with each control group, the superiority of IDegAsp in the reduction of HbA1c was significant only in the patients with a lower FPG-to-estimated average glucose ratio (0.49 ± 0.09), but not in those with a higher FPG-to-estimated average glucose ratio (0.79 ± 0.20).

CONCLUSIONS

We observed that IDegAsp was more effective than basal insulin in patients with an FPG lower than predicted by HbA1c, which might be related with insulin deficiency and postprandial hyperglycemia in patients on basal insulin therapy.

Synthesis of new clioquinol derivatives as potent α-glucosidase inhibitors; molecular docking, kinetic and structure-activity relationship studies

Diabetes mellitus is a chronic metabolic disorder with increasing prevalence and long-term complications. The aim of this study was to identify α-glucosidase inhibitory compounds with potential anti-hyperglycemic activity. For this purpose, a series of new clioquinol derivatives 2a-11a was synthesized, and characterized by various spectroscopic techniques. The enzyme inhibitory activities of the resulting derivatives were assessed using an in-vitro mechanism-based assay. All the tested compounds 2a-11a of the series showed a significant α-glucosidase inhibition with IC₅₀ values 43.86-325.81 µM, as compared to the standard drug acarbose 1C₅₀: 875.75 ± 2.08 µM. Among them, compounds 4a, 5a, 10a, and 11a showed IC₅₀ values of 105.51 ± 2.41, 119.24 ± 2.37, 99.15 ± 2.06, and 43.86 ± 2.71 µM, respectively. Kinetic study of the active analogues showed competitive, non-competitive, and mixed-type inhibitions. Furthermore, the molecular docking study was performed to elucidate the binding interactions of most active analogues with the various sites of α-glucosidase enzyme. The results indicate that these compounds have the potential to be further studied as new anti-diabetic agents.

Long-term Efficacy and Safety of Ultra Rapid Lispro in Japanese Patients With Type 1 Diabetes: Subpopulation Analysis of the 52-Week PRONTO-T1D Study

INTRODUCTION

The PRONTO-T1D study evaluated the efficacy and safety of ultra rapid lispro (URLi) versus lispro in adults with type 1 diabetes mellitus. After 26 weeks of treatment, mealtime and postmeal URLi provided effective and comparable glycemic control in a prespecified subpopulation analysis of Japanese patients from PRONTO-T1D. We present the results of a 52-week study which evaluated the long-term efficacy and safety of URLi in Japanese patients.

METHODS

After an 8-week lead-in period to optimize basal insulin treatment, Japanese patients were randomized to one of three treatment groups: the 52-week double-blind mealtime URLi (n = 62) or mealtime lispro (n = 59) group, respectively, or the 52-week open-label postmeal URLi (n = 46) group.

RESULTS

At week 52, there were no statistically significant differences in change from baseline in hemoglobin A1c (HbA1c) between Japanese patients on URLi and those on lispro; the least-squares mean (LSM) treatment difference was 0.04% (95% confidence interval [CI] - 0.18, 0.25) between mealtime URLi and lispro, and 0.04% (95% CI - 0.19, 0.28) between postmeal URLi and mealtime lispro. No significant between-group differences were observed in the number of patients achieving the HbA1c target of < 7.0% (20.0, 30.5 and 16.3% of those on mealtime URLi, mealtime lispro and postmeal URLi, respectively). Daily average blood glucose levels in the 10-point self-monitored blood glucose profiles at week 52 were similar between treatments. However, compared with lispro, lower blood glucose levels were observed for the mealtime URLi group at the morning 1- and 2-h postmeal time points with LSM differences of - 32.7 mg/dL (- 1.82 mmol/L) (p = 0.005) and - 23.2 mg/dL (- 1.29 mmol/L) (p = 0.029), respectively. There were no significant treatment differences in the incidences of treatment-emergent adverse events, documented hypoglycemia and severe hypoglycemia; however, the rate of documented hypoglycemia was lower in the mealtime URLi arm compared with the lispro arm.

CONCLUSIONS

Overall glycemic control and improved postprandial glucose via self-monitoring was maintained in Japanese patients following 52 weeks of treatment with URLi versus lispro, including postmeal URLi administration.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03214367.

Comparative effects of insulin glulisine and lispro on postprandial plasma glucose and lipid profile in Japanese patients with type 2 diabetes mellitus

Objective

The control of postprandial plasma glucose (PPG) excursions is critical in the prevention of diabetic complications. Controversy remains on the differences in postprandial actions of insulin glulisine and lispro. The aim of this study was to define the differences in the efficacy of these two insulin analogues on PPG.

Methods

The study subjects were 20 in-hospital patients with type 2 diabetes mellitus (T2DM). Plasma glucose (PG) was tightly controlled with basal insulin and insulin glulisine or lispro, and then glulisine or lispro were switched to the other insulin analog every other day for 6 study days. PG was measured before breakfast and 0.5-, 1-, and 2 h-postprandial during the study. Postprandial plasma C-peptide and lipids were analyzed in the first 2 days of the study. Postprandial increments in each parameter were compared between glulisine and lispro.

Results

Whereas the median value of 0.5 h-Δ-PPG was comparable in glulisine and lispro, the 1 h-Δ-PPG was significantly lower with lispro than with glulisine (41 vs 53 mg/dl, respectively, p = 0.03). Similarly, the 2 h-Δ-PPG with lispro was 10 mg/dl lower than that with glulisine (35 vs 45 mg/dl, respectively, p = 0.05). In parallel with PPG, Δ-C-peptide at 1- and 2 h-postprandial were significantly lower with lispro than glulisine (0.50 vs 0.75 ng/ml, respectively, and 0.55 vs 0.75 ng/ml, respectively). The increment in LDL-C and HDL-C was significantly lower with lispro than with glulisine at 0.5 h-postprandial.

Conclusion

Insulin lispro seems superior to glulisine in the control of PPG in Japanese patients with T2DM.

Thresholds for postprandial hyperglycemia and hypertriglyceridemia associated with increased mortality risk in type 2 diabetes patients: A real-world longitudinal study

AIMS/INTRODUCTION

To identify thresholds for postprandial hyperglycemia and hypertriglyceridemia predictive of all-cause mortality in patients with type 2 diabetes.

MATERIALS AND METHODS

A total of 1,928 patients with type 2 diabetes visited our clinic for the first time from 1995 to 1999 and were followed up for ≥1 year. During the first year, 2-h post-breakfast blood glucose (2h-BG) levels were measured in 1,122 patients (BG cohort) and postprandial serum triglyceride (ppTG) levels were measured in 1,826 patients (TG cohort). Patients were retrospectively followed until 2017 and administered questionnaires. Associations between 2h-BG and ppTG levels and mortality risk were assessed by the multivariate Cox regression analysis.

RESULTS

Over of 17,429 person-years, 162 deaths occurred in the BG cohort, and over 28,026 person-years, 253 deaths occurred in the TG cohort. Hazard ratios (HRs) with 95% confidence intervals for all-cause mortality per 1-standard deviation increases in 2h-BG and ppTG were 1.34 (1.08-1.67) and 1.24 (1.06-1.45), respectively. HRs showed increasing trends across quintiles of 2h-BG (P = 0.034) and ppTG (P = 0.007). The HR was significantly elevated (2.37, 1.26-4.47) in the fifth quintile of 2h-BG (≥13.8 mmol/L) compared with the first quintile (<7.0 mmol/L; P = 0.008). The HR was also significantly elevated (1.63, 1.03-2.60) in the fifth quintile of ppTG (≥2.30 mmol/L) compared with the first quintile (<0.91 mmol/L; P = 0.038).

CONCLUSIONS

Postprandial hyperglycemia and hypertriglyceridemia were associated with all-cause mortality in patients with type 2 diabetes. We propose thresholds of 13.8 mmol/L 2h-BG and 2.30 mmol/L ppTG to identify patients at increased risk of mortality.

Inhibition mechanism of diacylated anthocyanins from purple sweet potato (Ipomoea batatas L.) against α-amylase and α-glucosidase

This study aimed to evaluate inhibitory activity of anthocyanins from purple sweet potato and blueberries against α-amylase and α-glucosidase, as well as investigate the inhibition mechanism of diacylated anthocyanins (Diacylated AF-PSP). Diacylated AF-PSP better inhibited α-amylase (IC₅₀ = 0.078 mg mL^-1) and α-glucosidase (IC₅₀ = 1.56 mg mL^-1) than other anthocyanin fractions, which was a mixed-type inhibitor. Fluorescence analysis indicated that Diacylated AF-PSP bound to the enzymes mainly through hydrogen bonds and influenced the microenvironments of proteins. Additionally, surface hydrophobicity and circular dichroism spectra results confirmed conformational changes in the enzymes induced by Diacylated AF-PSP. Molecular docking further demonstrated the interaction of Diacylated AF-PSP with enzyme active site, which might be stabilized by its acyl groups. Finally, 160 mg kg^-1 Diacylated AF-PSP significantly decreased (p < 0.01) blood glucose level peak by 20.52% after starch administration in SD rats. This study provided theoretical evidences for utilization of diacylated anthocyanins in hyperglycemia-management functional foods.

Basal insulin ameliorates post-breakfast hyperglycemia via suppression of post-breakfast proinsulin/C-peptide ratio and fasting serum free fatty acid levels in patients with type 2 diabetes

Background

In general, basal insulin targets fasting plasma glucose (FPG) levels, and prandial insulin targets postprandial glucose (PPG) levels. However, the effects of basal insulin on PPG levels are controversial. We investigated the effect of basal insulin on postprandial hyperglycemia using a test meal at breakfast as well as compared differences between degludec and glargine.

Methods

A total of 20 participants with type 2 diabetes were randomly assigned to degludec (n = 10) or glargine (n = 10). We initiated basal-bolus insulin therapy and titrated only basal insulin until FPG was < 6.1 mmol/L. We evaluated changes in post-breakfast glucose levels and changes in clinical parameters such as serum C-peptide (CPR), proinsulin (PI), and free fatty acids (FFA) levels between the pre- and post-titration periods. Differences between degludec and glargine in the post-titration period were also evaluated.

Results

Post-breakfast glucose levels significantly decreased by 46.1% in the post-titration period compared with the pre-titration period (n = 20, p < 0.001). These decreases correlated positively with decreases in the post-breakfast PI/CPR ratio (r = 0.692, p < 0.001) and in fasting FFA levels (r = 0.720, p < 0.001). There were no significant differences in post-breakfast glucose levels between degludec and glargine. However, the hypoglycemic rate with degludec was significantly lower than with glargine.

Conclusion

Our results suggest that basal insulin with either degludec or glargine decreases the incidence of post-breakfast hyperglycemia accompanied by decreasing the post-breakfast PI/CPR ratio and fasting FFA levels in patients with type 2 diabetes.

Comparison of Glycemic Excursion Using Flash Continuous Glucose Monitoring in Patients with Type 2 Diabetes Mellitus Before and After Treatment with Voglibose

Purpose: To determine the effect of Voglibose add-on therapy on daily glycemic excursions (using FreeStyle^® Libre Pro™, a Flash glucose monitoring system) in Indian patients with type 2 diabetes mellitus (T2DM) receiving a stable dose of metformin (Met) or metformin+sulfonylurea (Met+SU). Patients and Methods: T2DM patients with glycosylated hemoglobin (HbA1c) ≥7.0% and at least two postprandial excursions ≥140 mg/dL (within 2 h of meal) during the screening phase (visit 1/day -14 ± 2) were enrolled in this prospective, multicenter interventional study. The patients were randomized at visit 2 (day 0 ± 2) to receive Voglibose 0.2 or 0.3 mg tablets (BID/TID) as add-on therapy to Met and Met+SU. All the patients were followed at day 14 ± 2 (visit 3), month 3 ± 14 days (visit 4), 14 weeks (i.e., visit 4 + 14 days) ±2 days (visit 5), and month 6 ± 14 days (visit 6). Continuous glucose monitoring was performed to study glycemic excursions at visits 2, 3, and 5. The study outcomes were: change in average number of glycemic excursions per day, percent time spent in glucose fluctuations, mean Postprandial glucose (PPG), Fasting plasma glucose (FPG), day and night time mean glucose levels from baseline to day 14 and week 14; change in mean amplitude of glycemic excursion (MAGE) from baseline to 14 weeks; and mean HbA1c level at 3 and 6 months. Results: Out of 110 patients enrolled, 101 patients (91.8%) (Met+SU+Voglibose: 73 and Met+Voglibose: 28) completed the study. There was a significant decrease in average number of glycemic excursions per day from baseline to day 14 in the Met+Sul+Voglibose group and to week 14 in the Met+Voglibose group. There was also a significant reduction in percent time spent above target glucose range from baseline to day 14 in both treatment groups and to week 14 in the Met+SU+Voglibose group. A significant reduction in mean PPG area under the curve, day and night time mean glucose levels, and mean FPG levels from baseline to day 14 was reported in both treatment groups. A significant reduction in night time glucose, and average MAGE and HbA1c levels was reported from baseline to week 14 in the Met+Voglibose group and the Met+SU+Voglibose group, respectively. At 6 months, body weight, glucose levels, cholesterol, low-density lipoprotein-cholesterol, and HbA1c were significantly lower, especially in the Met+SU+Voglibose arm. Conclusion: Voglibose was useful in reducing glycemic variability and improving glycemic control in Asian Indian adults with T2DM. (CTRI/2018/04/013074).

Postprandial glucose-lowering effect of cagaita (Eugenia dysenterica DC) fruit juice in dysglycemic subjects with metabolic syndrome: An exploratory study

Cagaita (Eugenia dysenterica DC) is an ellagitannin-containing Myrtaceae fruit from Cerrado biome. This fruit seems to be a promising candidate for an adjuvant in glucose regulation in healthy subjects. However, it is not known whether cagaita juice would have the same effect on dysglycemic subjects with metabolic syndrome (MetS). Therefore, the present work aimed to evaluate the effect of cagaita fruit juice on postprandial glycemia in dysglycemic subjects with MetS, and whether cagaita ellagitannins could be metabolized to urolithins. To evaluate glycemic effects, two different meals were consumed by volunteers (n = 12) with a 1-week interval among them. The first one consisted of white bread (50 g) plus water (300 mL) as a control; the second one, white bread (50 g) plus clarified cagaita juice (300 mL). Bioavailability was assessed in 24 h urine, after the consumption of a single amount of 300 mL of cagaita juice by healthy (n = 16) and MetS subjects (n = 7). The results showed that dysglycemic subjects with MetS presented a 53% reduction of incremental area under the curve (iAUC) of glucose, 38% reduction of insulin, 78% reduction of GIP (glucose-dependent insulinotropic polypeptide), and 58% reduction of C-peptide (p < 0.05), after the consumption of cagaita juice along with bread, in comparison to control water. However, both GLP-1 (glucagon-like peptide-1) and glucagon were not affected by cagaita juice ingestion. Concerning bioavailability, it was observed, for the first time, the metabolization of cagaita ellagitannins to urolithins by healthy and dysglycemic individuals with MetS, with a prevalence of metabotype B in both groups (44% and 42%, respectively), followed by metabotype A (37% and 29%, respectively), and metabotype 0 (19% and 29%, respectively).

Effect of the acute and chronic administration of Lupinus albus β-conglutin on glycaemia, circulating cholesterol, and genes potentially involved

Constituents of lupin seeds, like γ-conglutin and lupanine, have gained attention as potential complementary treatments for dysglycaemia management. Notwithstanding, the effect of other lupin components on carbohydrate metabolism, including β-conglutin protein, has received little attention. Here, we investigated the influence of the acute and chronic administration of β-conglutin on glycaemia modulation in normal and streptozotocin induced-to-diabetes rats. We analysed the liver transcriptome modulation exerted by β-conglutin in diabetes-induced rats using DNA microarrays to scout for potential molecular targets and pathways involved in this biological response. The acute administration of β-conglutin reduced the incremental area under the curve of glycaemia in normal and diabetes-induced animals. In a seven-day study with diabetic animals, glycaemia increased significantly in non-treated animals but remained unchanged in animals treated with a daily dose of β-conglutin. Total cholesterol was significantly lower at the end of the experimental period (-21.8 %, p = 0.039). The microarray and gene ontology analyses revealed several targets and pathways potentially modulated by β-conglutin treatment, including a possible down-regulation of Jun kinase activity. Moreover, our data indicate that targets related to oxidative stress, inflammation, and estrogenic activity might orchestrate these metabolic effects. In conclusion, our findings show that β-conglutin may help manage postprandial glycaemia and reduce cholesterol levels under the dysglycaemia stage. We identified and proposed new potential molecular targets for further research related to the mechanism of action of β-conglutin.

Integration of in silico, in vitro and ex vivo pharmacology to decode the anti-diabetic action of Ficus benghalensis L. bark

BACKGROUND

Traditionally, Ficus benghalensis L. is used to treat metabolic disorders and is also recorded in the Ayurvedic pharmacopeia of India. The present study aimed to evaluate the anti-diabetic property of hydroalcoholic extract/fraction(s) of F. benghalensis L. bark via in silico, in vitro, and ex vivo approach.

METHODS

Enzyme inhibitory activity, glucose uptake in rat hemidiaphragm, and glucose permeability, and adsorption assays were performed using in vitro and ex vivo methods as applicable. Further, the PASS was used to identify the probable lead enzyme inhibitors. The presence of predicted enzyme inhibitors was confirmed via the LC-MS. Similarly, the docking of ligands with respective targets was performed using autodock4.0.

RESULTS

Flavonoids rich fraction possessed the highest α-amylase, and α-glucosidase inhibitory activity followed by maximum efficacy for glucose uptake in rat hemidiaphragm. Similarly, the hydroalcoholic extract showed the highest efficacy to inhibit glucose diffusion. Likewise, 3,4-dihydroxybenzoic acid was predicted for the highest pharmacological activity for α-amylase, ursolic acid for PTP1B, and apigenin for α-glucosidase inhibition respectively. The LC-MS analysis also identified the presence of the above hit molecules in the hydroalcoholic extract.

CONCLUSION

The analogs of 3,4-dihydroxybenzoic acid, apigenin, and ursolic acid could be the choice of lead hits as the α-amylase, α-glucosidase, and PTP1B inhibitors respectively. Additionally, the majority of secondary metabolites from the hydroalcoholic extract of F. benghalensis may be involved in enhancing the glucose uptake to support the process of glycogenesis.

A time to revisit the two oldest prandial anti-diabetes agents: acarbose and repaglinide

PURPOSE

Compared with newer prandial anti-diabetes agents, repaglinide and acarbose are unique in being globally available in generic versions, being oral, and being the cheapest of all. The aim of this study was to compare their efficacy when used alone or in combination.

METHODS

In a randomized, double-blind, prospective study, 358 recently diagnosed type 2 diabetes (T2D) patients, who on a combined therapy with metformin and insulin glargine had a fasting plasma glucose (FGP) of <7.2 mmol/L but a 2-h postprandial plasma glucose (2hPPG) >10 mmol/L, were assigned to three groups of additional treatment with either repaglinide, acarbose, or repaglinide-plus-acarbose for 4 months.

RESULTS

With intention-to-treat analysis, 63% of repaglinide group, 45.4 percent of acarbose group, and 75.7% of repaglinide-plus-acarbose group reached the primary endpoint of 2hPPG < 10 mmol/L while maintaining FPG < 7.2 mmol/L. Treatment adherence rate was 75.6% with repaglinide, 61.4% with acarbose, and 81.3% with repaglinide-plus-acarbose (p = 0.001). Among the groups, weight was significantly lower in acarbose group (p < 0.05). Twenty-one percent of repaglinide patients, 4.9% of acarbose subjects, and 10.3% of repaglinide-plus-acarbose cases reported at least one episode of hypoglycemia (p < 0.005). HbA1C and basal insulin requirement were significantly lower in repaglinide group (p = 0.004, p = 0.0002). Triglycerides were lowest in acarbose group (p = 0.005).

CONCLUSIONS

Both acarbose and repaglinide were vastly effective in lowering postprandial hyperglycemia of recently diagnosed T2D. When combined, they were even more efficacious and the disease had a better outcome. Compared with newer peers, these two are particularly useful where and when cost consideration in diabetes treatment is a prime concern.

An overview on the role of bioactive α-glucosidase inhibitors in ameliorating diabetic complications

Recently the use of bioactive α-glucosidase inhibitors for the treatment of diabetes have been proven to be the most efficient remedy for controlling postprandial hyperglycemia and its detrimental physiological complications, especially in type 2 diabetes. The carbohydrate hydrolysing enzyme, α-glucosidase, is generally competitively inhibited by the α-glucosidase inhibitors and results in the delayed glucose absorption in small intestine, ultimately controlling the postprandial hyperglycemia. Here we have reviewed the most recent updates in the bioactive α-glucosidase inhibitors category. This review provides an overview of the α-glucosidase inhibitory potentials and efficiency of controlling postprandial hyperglycemia of various bioactive compounds such as flavonoids, phenolic compound, polysaccharide, betulinic acid, tannins, anthocyanins, steroids, polyol, polyphenols, galangin, procyanidins, hydroxyl-α-sanshool, hydroxyl-β-sanshool, erythritol, ganomycin, caffeoylquinic acid, resin glycosides, saponins, avicularin, oleanolic acids, urasolic acid, ethanolic extracts etc., from various dietary and non-dietary naturally occurring sources.

Effect of postprandial moderate-intensity walking for 15-min on glucose homeostasis in type 2 diabetes mellitus patients

Aim

Diabetes patients usually have a low activity level and complain about lack of time. Therefore, we investigated the effect of short time, postprandial moderate-intensity exercise on glucose homeostasis in type 2 diabetes patients.

Methods

Eleven patients with type 2 diabetes were recruited. Patients spent the first day of the study without exercise (non-exercise day; NE day). In the second day, they walked at moderate-intensity (40% of the maximum heart rate reserve) for 15 min, 30 min after each meal (exercise day; E day). Glucose homeostasis was estimated by a continuous glucose monitor (CGM). All meals during the study were of standard composition. We compared NE day and E day concerning 24-h glucose homeostasis and 3 h postprandial glucose levels by the incremental area under the curve (iAUC) method. Medications were not changed during the study.

Results

The number of patients under basal supported oral therapy, intensive insulin therapy and oral hypoglycemic agents (OHA) were 5, 4 and 2, respectively. The blood glucose standard deviation over 24 h and the iAUC for the 24-h glycemic variability (NE day vs. E day; 34,765 [21,424-56,014] vs. 23,205 [15,323-39,779]) were smaller in E day than in NE day.

Conclusion

These results suggest that postprandial moderate-intensity walking, easily performable in daily life activities, was effective for improving glucose homeostasis. Further study should be performed to clarify the relationship between postprandial walk and drug therapy (insulin and OHA), including insulin secretory ability.

The Effects of Mobile-App-Based Low-Carbohydrate Dietary Guidance on Postprandial Hyperglycemia in Adults with Prediabetes

INTRODUCTION

Postprandial hyperglycemia is independently associated with many adverse complications, while diets with a low glycemic load are beneficial in improving post-meal glucose levels. This study aims to determine if mobile-app-based low-carbohydrate dietary guidance will reduce exposure to postprandial hyperglycemia in adults with prediabetes.

METHODS

This single-blind, randomized controlled pilot study included 100 participants (39 men; mean age 53.6 ± 11.9 years) and was performed in the PKU Care CNOOC Hospital, China. The intervention group (n = 57) received low-carbohydrate dietary guidance through a moblie app (CAReNA) for 3 months, while the control group (n = 43) only received health education on a diabetic diet. The primary outcome was change in time of postprandial hyperglycemia between baseline and 3 months.

RESULTS

The study revealed that the mean time in postprandial hyperglycemia (> 7.8 mmol/l [140 mg/dl]) monitored by flash glucose monitoring changed from 3.27 h/day at baseline to 2.34 h/day at 3 months in the intervention group and from 3.08 h/day to 2.96 h/day in the control group, with a between-group difference of - 0.81 h/day (P < 0.05). Fasting plasma glucose and glycated hemoglobin (HbA1c) in the intervention group decreased significantly, although no significant difference was seen between the two groups. Compared with the control group, the intervention group had a significant decrease in anthropometric and body composition measurements as well as triglycerides.

CONCLUSION

The mobile-app-based low-carbohydrate dietary guidance effectively reduced the time spent in postprandial hyperglycemia in adults with prediabetes. This new type of nutritional management has beneficial effects on people with prediabetes and needs further research.

CLINICAL TRIAL REGISTRATION

ChiCTR1900024880.

Ultra-Rapid Lispro Efficacy and Safety Compared to Humalog® in Japanese Patients with Type 1 Diabetes: PRONTO-T1D Subpopulation Analysis

INTRODUCTION

We evaluated the efficacy and safety of ultra-rapid lispro (URLi) in comparison to lispro in a subgroup analysis of Japanese adults with type 1 diabetes mellitus from the phase 3 PRONTO-T1D trial.

METHODS

After an 8-week lead-in to optimize basal insulin treatment, patients were randomized to 52-week double-blind mealtime URLi or lispro, or 26-week open-label postmeal URLi. The primary endpoint was change in hemoglobin A1c (HbA1c) from baseline (week 0) to week 26 between mealtime URLi and lispro. The multiplicity adjusted objectives were 1- and 2-h postprandial glucose (PPG) excursions after a meal test between mealtime URLi and lispro, and change in HbA1c from baseline to week 26 between postmeal URLi and mealtime lispro.

RESULTS

This manuscript presents pre-specified exploratory analyses of 26-week data from Japanese patients randomized to double-blind URLi (n = 62) or lispro (n = 59), or open-label URLi (n = 46). Mean baseline HbA1c levels were 7.52% for mealtime URLi, 7.44% for lispro, and 7.51% for postmeal URLi at randomization. At week 26, the least squares mean (LSM) difference compared to lispro was 0.04% (95% confidence interval [CI] - 0.14 to 0.22) for mealtime URLi, and 0.16% (95% CI - 0.04 to 0.35) for postmeal URLi. In comparison to lispro, mealtime URLi resulted in statistically significantly lower 1- and 2-h PPG excursions during the mixed-meal tolerance test. LSM differences were - 40.5 mg/dL, 95% CI - 59.5 to 21.4 (- 2.25 mmol/L, 95% CI - 3.3 to - 1.2) for 1-h PPG excursions and - 51.7 mg/dL, 95% CI - 81.7 to - 21.8 (- 2.87 mmol/L, 95% CI - 4.5 to - 1.2) for 2-h PPG excursions at week 26. There were no significant treatment differences in rates of severe/overall hypoglycemia, or incidence of treatment-emergent adverse events.

CONCLUSIONS

Mealtime and postmeal URLi provide effective and comparable glycemic control in Japanese patients. Mealtime URLi demonstrated more effective PPG control compared to lispro.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03214367.

Ultra-Rapid Lispro Efficacy and Safety Compared to Humalog® in Japanese Patients With Type 2 Diabetes: PRONTO-T2D Subpopulation Analysis

INTRODUCTION

The aim of this study was to evaluate the efficacy and safety of ultra-rapid lispro (URLi) versus lispro in a subgroup analysis of Japanese adults with type 2 diabetes mellitus (T2DM) from the phase 3 PRONTO-T2D trial.

METHODS

After an 8-week lead-in period during which patients transitioned to insulin lispro 3 times a day before main meals in association with basal insulin (glargine or degludec), the patients were randomized to 26 weeks of double-blind URLi or lispro injected immediately prior to meals. The primary endpoint was change in hemoglobin A1c (HbA1c) from baseline to week 26 between URLi and lispro. The multiplicity-adjusted objectives were 1- and 2-h postprandial glucose (PPG) excursions after a test meal and change in HbA1c from baseline to week 26 in the URLi and lispro groups.

RESULTS

Results were obtained from prespecified exploratory analyses of 26-week data in Japanese patients randomized to receive URLi (n = 47) or lispro (n = 46). Mean baseline HbA1c levels significantly improved during the lead-in period to a baseline value of 7.50% and 7.60% in patients subsequently randomized to the URLi and lispro treatment groups, respectively. At week 26, the least squares mean (LSM) difference in HbAc1 between the URLi and lispro groups was 0.13% (95% confidence interval [CI] - 0.12 to 0.39) (1.4 mmol/mol, 95% CI - 1.3 to 4.2). Although there were no significant differences in PPG excursions at any time-point, numerically smaller PPG excursions were consistently observed from 30 min to 3 h during the mixed-meal tolerance test in patients on URLi compared to those on lispro. LSM differences in PPG excursions at week 26 were - 10.5 mg/dL (95% CI - 32.7 to 11.7) (- 0.58 mmol/L, 95% CI - 1.82 to 0.65) at 1 h and - 14.9 mg/dL (95% CI - 40.3 to 10.5) (- 0.83 mmol/L, 95% CI - 2.24 to 0.58) at 2 h. There were no significant differences between treatments in rates of severe/overall hypoglycemia or incidence of treatment-emergent adverse events.

CONCLUSIONS

URLi administered as prandial insulin in combination with basal insulin provides effective glycemic control when administered immediately before a meal in Japanese patients with T2DM. URLi was well tolerated in this population.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03214380.

Effect of postprandial hyperglycemia at clinic visits on the incidence of retinopathy in patients with type 2 diabetes: An analysis using real-world long-term follow-up data

AIMS/INTRODUCTION

There is little evidence on the role of postprandial glycemia in the incidence of diabetic retinopathy (DR) in a real-world setting. We aimed to assess the effect of postprandial hyperglycemia at clinic visits on the incidence of DR in patients with type 2 diabetes, and whether its effect differs depending on glycated hemoglobin (HbA1c) values and age.

MATERIALS AND METHODS

Intrapersonal mean blood glucose levels at 1-2 h post-breakfast (1-2h-PBBG), post-lunch (1-2 h-PLBG) and both (1-2h-PBLBG) during 2 years from the first visit were used as baseline data. This retrospective cohort study enrolled 487, 323 and 406 patients who had 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG measurements, respectively. These three groups were followed from 1999 up through 2017.

RESULTS

DR occurred in 145, 92 and 126 patients in the 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG groups, respectively. Multivariate Cox regression analysis showed that the mean 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG levels were significant predictors of DR, independent of mean HbA1c. In patients with mean HbA1c <7.0% and those with a baseline age <60 years, the mean 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG levels were significant predictors.

CONCLUSIONS

Postprandial hyperglycemia at clinic visits might predict the incidence of DR, independent of HbA1c. The effect of postprandial hyperglycemia on DR is obvious in patients with well-controlled HbA1c and in younger patients. Even with the lower HbA1c level, correcting postprandial hyperglycemia is important for preventing DR, especially in middle-aged adults with type 2 diabetes.

Effect of High β-glucan Barley on Postprandial Blood Glucose and Insulin Levels in Type 2 Diabetic Patients

The aim of our study was to investigate whether high β-glucan-containing barley (7.2 g per 100 g) improves postprandial plasma glucose levels and suppresses postprandial insulin levels during a meal tolerance test in type 2 diabetic patients. A meal tolerance test (500 kcal) was conducted using two types of test meals: a test meal with white rice (WR) alone (WR diet) and a test meal with WR mixed with 50% barley (BR diet) as staple food. The side dish was the same in the both meals. The changes in plasma glucose and serum C-peptide immunoreactivity (CPR) levels for 180 minutes after ingestion of the test meals were compared. Ten patients with type 2 diabetes (age 52.5 ± 15.1 years, and 7 males and 3 females) were included in this study. The mean HbA1c level and body mass index were 8.8 ± 1.4%, and 29.7 ± 4.5 kg/m², respectively. Plasma glucose levels after ingestion of the WR diet or BR diet peaked at 60 minutes, which showed no significant differences between the two types of test meals. However, the incremental area under the curve (IAUC) of plasma glucose levels after ingestion of BR diet was significantly lower than that of WR diet. The serum CPR levels at 180 min and their IAUC over 180 minutes after ingestion of BR diet were significantly lower than those of WR diet. Conclusion: Increase in postprandial plasma glucose and insulin levels was suppressed by mixing high-β-glucan barley with WR in type 2 diabetic patients.

Consumption of a meal containing refined barley flour bread is associated with a lower postprandial blood glucose concentration after a second meal compared with one containing refined wheat flour bread in healthy Japanese: A randomized control trial

OBJECTIVE

Foods reducing postprandial hyperglycemia could suppress the postprandial blood glucose response after the next meal (a "second-meal" effect). However, the second-meal effect of refined barley flour bread has not been evaluated. The aim of this study is to determine whether consumption of refined barley flour bread reduces postprandial glucose concentrations after this and the subsequent meal.

METHODS

We enrolled 23 healthy young Japanese adults and conducted a randomized, double-blind, placebo-controlled, crossover study. The participants consumed refined barley flour bread containing 2.5 g β-glucan or refined wheat flour bread in a first meal, then consumed three rice balls as a second meal. Their postprandial blood glucose concentrations were measured 0, 15, 30, 45, 60, 90, and 120 min after both meals. Participants with fasting glucose concentrations above the diagnostic threshold for diabetes were excluded.

RESULTS

The blood glucose concentration 30 min after the first meal was significantly lower (P < 0.05) if refined barley flour bread (7.1 ± 1.0 mmol/L) rather than refined wheat flour bread (7.7 ± 1.2 mmol/L) was consumed. Significantly lower glucose concentrations after the second meal measured at 60 (P < 0.05, barley flour bread: 8.7 ± 1.8 mmol/L, wheat flour bread: 9.3 ± 1.7 mmol/L) and 90 min (P < 0.01, barley flour bread: 7.8 ± 1.4 mmol/L, wheat flour bread: 8.8 ± 2.1 mmol/L) were lower in participants who had previously consumed the refined barley flour bread.

CONCLUSIONS

Consumption of bread made with refined barley flour lowers postprandial blood glucose concentration after this and a subsequent meal compared with the consumption of refined wheat flour bread in healthy young Japanese adults.

5,7-Dimethoxy-3-(2'-hydroxybenzyl)-4-chromanone inhibits α-glucosidase in vitro and alleviates postprandial hyperglycemia in diabetic mice

This study was designed to investigate the inhibitory activities of 5,7-dimethoxy-3-(2'hydro-xybenzyl)-4-chromanone (5,7-D chromanone) isolated from Portulaca oleracea L. on carbohydrate digesting enzymes and its ability to improve postprandial hyperglycemia in streptozotocin-induced diabetic mice. 5,7-D chromanone strongly inhibited α-glucosidase and α-amylase (half-maximal inhibitory concentration, IC₅₀; 15.03 ± 2.59 μM and 12.39 ± 2.16 μM, respectively). The inhibitions were more effective than acarbose, which was the positive control. The increase in blood glucose level after ingesting starch was more significantly alleviated in the 5,7-D chromanone ingested group than in the control group of diabetic mice. In the control group, blood glucose levels were 24.64 ± 1.73, 27.22 ± 1.58, and 26.37 ± 1.41 mM, and in the 5,7-D chromanone ingested group were 23.87 ± 1.10, 23.38 ± 1.32, and 21.42 ± 1.36 mM at 30, 60, and 120 min, respectively. In addition, the area under the curve of blood glucose significantly declined with 5,7-D chromanone ingestion in diabetic mice. The results indicate that 5,7-D chromanone can help lower postprandial hyperglycemia by inhibiting carbohydrate digesting enzymes.

Impact of serum 1,5-anhydro-D-glucitol level on the prediction of severe coronary artery calcification: an intravascular ultrasound study

BACKGROUND

A low 1,5-anhydro-D-glucitol (AG) blood level is considered a clinical marker of postprandial hyperglycemia. Previous studies reported that 1,5-AG levels were associated with vascular endothelial dysfunction and coronary artery disease (CAD). However, the association between 1,5-AG levels and coronary artery plaque in patients with CAD is unclear.

METHODS

This study included 161 patients who underwent percutaneous coronary intervention for CAD. The culprit plaque characteristics and the extent of coronary calcification, which was measured by the angle of its arc, were assessed by preintervention intravascular ultrasound (IVUS). Patients with chronic kidney disease or glycosylated hemoglobin ≥ 7.0 were excluded. Patients were divided into 2 groups according to serum 1,5-AG levels (< 14.0 μg/mL vs. ≥ 14 μg/mL).

RESULTS

The total atheroma volume and the presence of IVUS-attenuated plaque in the culprit lesions were similar between groups. Calcified plaques were frequently observed in the low 1,5-AG group (p = 0.06). Compared with the high 1,5-AG group, the low 1,5-AG group had significantly higher median maximum calcification (144° vs. 107°, p = 0.03) and more frequent calcified plaques with a maximum calcification angle of ≥ 180° (34.0% vs. 13.2%, p = 0.003). Multivariate logistic regression analysis showed that a low 1,5-AG level was a significant predictor of a greater calcification angle (> 180°) (OR 2.64, 95% CI 1.10-6.29, p = 0.03).

CONCLUSIONS

Low 1,5-AG level, which indicated postprandial hyperglycemia, was associated with the severity of coronary artery calcification. Further studies are needed to clarify the effects of postprandial hyperglycemia on coronary artery calcification.

Comparison of glucose monitoring between Freestyle Libre Pro and iPro2 in patients with diabetes mellitus

AIMS/INTRODUCTION

Flash and continuous glucose monitoring systems are becoming prevalent in clinical practice. We directly compared a flash glucose monitoring system (FreeStyle Libre Pro [FSL-Pro]) with a continuous glucose monitoring system (iPro2) in patients with diabetes mellitus.

MATERIALS AND METHODS

Glucose concentrations were simultaneously measured using the FSL-Pro, iPro2 and self-monitoring blood glucose in 10 patients with diabetes mellitus, and agreement among them was assessed.

RESULTS

Parkes error grid analysis showed that the 92.9 and 7.1% of glucose values measured using the FSL-Pro fell into areas A and B, respectively, and that 96.3, 2.8 and 0.9% of those determined using iPro2 fell into areas A, B and C, respectively. The median absolute relative differences compared with self-monitoring blood glucose were 8.1% (3.9-12.7%) and 5.0% (2.6-9.1%) for the FSL-Pro and iPro2, respectively. Analysis of 5,555 paired values showed a close correlation between FSL-Pro and iPro2 glucose values (ρ = 0.96, P < 0.01). Notably, 65.3% of all glucose values were lower for the FSL-Pro than the iPro2. Median glucose values also decreased by 3.3% for the FSL-Pro compared with the iPro2 (177.0 [133.0-228.0] vs 183.0 [145.0-230.0] mg/dL, P < 0.01). The difference in glucose values between the two systems was more pronounced in hypoglycemia. The median absolute relative difference between FSL-Pro and iPro2 during hypoglycemia was much larger than that during euglycemia and hyperglycemia.

CONCLUSIONS

Both the FSL-Pro and iPro2 systems are clinically acceptable, but glucose values tended to be lower when measured using the FSL-Pro than the iPro2. Agreement was not close between these systems during hypoglycemia.

Behavioral Strategies to Lower Postprandial Glucose in Those with Type 2 Diabetes May Also Lower Risk of Coronary Heart Disease

INTRODUCTION

Efforts to lower glycosylated hemoglobin (A1c) in patients with type 2 diabetes (T2D) are intended to reduce the risk of diabetic complications, but A1c is not the only factor contributing to this risk. Consequently, we re-analyzed published data from a broad-spectrum lifestyle intervention that lowered A1c to assess its effectiveness in lowering the overall risk of two complications of T2D, namely, coronary heart disease (CHD) and stroke.

METHODS

Data from 37 adults who participated in a randomized clinical trial of a lifestyle intervention intended to reduce postprandial glucose (PPG) were re-analyzed for their pre- and post-treatment risk of CHD and stroke using the T2D-specific UK Prospective Diabetes Study (UKPDS) v2.0 risk algorithm.

RESULTS

Compared to participants who received routine care, those using the lifestyle intervention had a significantly greater reduction in 10-year risk for CHD, but not for stroke.

CONCLUSION

These secondary analyses suggest that broad-spectrum lifestyle interventions that focus on lowering PPG may lower the risk of future CHD, which could guide future research.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT02432391.

Association between postprandial hyperglycemia at clinic visits and all-cause and cancer mortality in patients with type 2 diabetes: A long-term historical cohort study in Japan

AIMS

To evaluate the effect of postprandial hyperglycemia at clinic visits on all-cause and cancer mortality independent of glycated hemoglobin (HbA1c) levels in a real-world setting in Japanese patients with type 2 diabetes. We also investigated age at death.

METHODS

This historical cohort study included 1582 patients with type 2 diabetes who first visited our clinic from 1995 to 1998 and continued visiting for at least 1 year. The patients were followed up through 2017. Blood glucose levels at 2 h ± 30 min post-breakfast (2h-PBBG) were measured in 926 patients during the first year. The first measurements of 2h-PBBG levels were used as a measure of postprandial hyperglycemia.

RESULTS

A total of 233 patients died. The average age at death (men/women) was 75.6/80.8 years. A total of 139 patients who had 2h-PBBG levels measured died, including 46 deaths from cancer. Multivariate Cox regression analysis showed that 2h-PBBG levels significantly predicted all-cause and cancer mortality independent of HbA1c levels.

CONCLUSIONS

Postprandial hyperglycemia at clinic visits may be associated with all-cause and cancer mortality in patients with type 2 diabetes independent of HbA1c levels. As this is a small observational study, further studies are warranted to confirm our findings.

Effect of High β-glucan Barley on Postprandial Blood Glucose Levels in Subjects with Normal Glucose Tolerance: Assessment by Meal Tolerance Test and Continuous Glucose Monitoring System

The effect of white rice (WR) mixed with high β-glucan-containing barley at 50% on improvement of postprandial blood glucose levels was assessed by meal tolerance test and continuous glucose monitoring (CGM) in 15 healthy subjects with normal glucose tolerance (age 31.6 ± 12.9 years old, 4 males and 11 females). A meal tolerance test (500 kcal) was conducted using 2 types of test meals: a test meal only with WR and a test meal WR mixed 50% barley, and the side dish was the same in both meals. Blood glucose levels of the subjects 180 minutes after ingestion of the test meals were compared. In addition, a CGM device was attached to the subjects for 2 days when the WR or barley as a staple food was provided 3 times a day for consecutive days, and the daily variation of glucose was investigated. The glucose levels 30 minutes after dietary loads and the area under the blood concentration-time curve over 180 minutes were significantly decreased in the barley consumption group. In CGM, 24-hour mean blood glucose and 24-hour standard deviation of blood glucose were also significantly decreased after ingestion of the barley. Postprandial glucose level elevation was suppressed by mixing high-β-glucan barley with WR in subjects with normal glucose tolerance.

Postprandial anti-hyperglycemic effect of vitamin B6 (pyridoxine) administration in healthy individuals

Postprandial blood glucose lowering effect of vitamin B₆ (pyridoxine) was evaluated in healthy individuals with normal blood glucose levels. Blood glucose levels were measured every 30 min for 2 h after oral sugar administration with or without 50 mg of pyridoxine. Pyridoxine significantly lowered the postprandial blood glucose levels at 30 min (from 165.95 ± 17.19 to 138.36 ± 20.43, p < 0.01) and 60 min (from 131.40 ± 17.20 to 118.50 ± 15.95) after administration. In addition, the area under the concentration-time curve (AUCt) was reduced by about 8.3% (from 257.08 ± 22.38 to 235.71 ± 12.33, p < 0.05) and the maximum concentration of blood glucose (Cmax) was reduced by about 13.8% (from 165.95 ± 17.19 to 143.07 ± 11.34, p < 0.01) when compared with those of the control group. Our findings suggest that pyridoxine supplementation may be beneficial for controlling postprandial hyperglycemia.

Bedtime-to-Morning Glucose Difference and iGlarLixi in Type 2 Diabetes: Post Hoc Analysis of LixiLan-L

INTRODUCTION

A difference of ≥ 50-55 mg/dL between bedtime and morning glucose (BeAM) values in patients with type 2 diabetes (T2D) on basal insulin is an indicator of poor postprandial glucose control. This analysis compared the effect of treatment with a fixed-ratio combination of insulin glargine/lixisenatide (iGlarLixi) vs insulin glargine (iGlar) on BeAM values, and evaluated the impact of BeAM values on glycemic and safety endpoints.

METHODS

In this post hoc analysis of 517 participants from the LixiLan-L trial, change in BeAM values and composite efficacy and safety endpoints stratified by BeAM value < 55 mg/dL or ≥ 55 mg/dL were evaluated in patients with T2D uncontrolled on basal insulin randomized to iGlarLixi or iGlar over 30 weeks (LixiLan-L).

RESULTS

Greater reductions in BeAM values were seen with iGlarLixi vs iGlar, and a higher proportion of patients reached a BeAM value < 55 mg/dL in the iGlarLixi arm. A BeAM value < 55 mg/dL was associated with improved glycemic control, lower risk of hypoglycemia, and a greater proportion of patients achieving glycemic targets without hypoglycemia or weight gain. Greater reductions in BeAM values were seen with iGlarLixi vs iGlar, irrespective of stratification by glycated hemoglobin A_1c or glycemic endpoints.

CONCLUSIONS

Greater reductions in bedtime-to-morning glucose differential, or BeAM, were observed with iGlarLixi vs iGlar in patients with T2D uncontrolled on basal insulin, reflecting better overall control of both fasting and prandial glucose and more appropriate matching of therapy to physiologic needs.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02058160.

FUNDING

Sanofi US, Inc.

Improved Postprandial Glucose with Inhaled Technosphere Insulin Compared with Insulin Aspart in Patients with Type 1 Diabetes on Multiple Daily Injections: The STAT Study

BACKGROUND

The majority of therapies have generally targeted fasting glucose control, and current mealtime insulin therapies have longer time action profiles than that of endogenously secreted insulin. The primary purpose of this study was to assess both glucose time-in-range (TIR: 70-180 mg/dL) and postprandial glucose excursions (PPGE) in 1-4 h using a real-time continuous glucose monitor (CGM) with Technosphere insulin (TI) versus insulin aspart in patients with type 1 diabetes (T1DM) on multiple daily injections (MDI).

RESEARCH DESIGN AND METHODS

This pilot, investigator-led, collaborative, open-label, multicenter, clinical research trial enrolled 60 patients with T1DM with HbA1c levels ≥6.5% and ≤10%. Individuals were randomized to treatment with titrated TI (n = 26) or titrated insulin aspart (n = 34), stratified by baseline HbA1c levels (≤8% or >8%). All were required to wear a real-time CGM throughout the trial. All patients in the TI group were advised to take supplemental inhalations at 1 and 2 h after meals if indicated based on postprandial glucose (PPG) values. The coprimary outcomes were assessed both in the full intent-to-treat population and in those individuals randomized to TI who were compliant with supplemental doses ≥90% of the time (n = 15). The CGM data were analyzed using linear regression models.

RESULTS

Overall, those treated with TI versus aspart achieved comparable TIR, but less time spent in hypoglycemia (<60 and <50 mg/dL, both P < 0.05). In the TI-compliant group (n = 15), TIR was significantly greater (62.5% ± 2.6% vs. 53.8% ± 1.7%, P = 0.009) and time in hyperglycemia >180 mg/dL was lower (34.2% ± 2.7% vs. 41.0% ± 1.7%, P = 0.045) as compared with the aspart group. PPG was also significantly lower in the TI cohort at 60 and 90 min postmeal, and PPGE were lower in the TI-compliant group as compared with the aspart group over 1-4-h postmeal (P < 0.05). In addition, there was weight gain in the aspart group compared with weight loss in the TI group (P = 0.006) despite higher prandial TI insulin dose.

CONCLUSIONS

We conclude that using TI appropriately at mealtimes with supplemental dosing improves prandial glucose (TIR and 1-4 h) control without any increase in time in hypoglycemia or weight gain in patients with T1DM on MDI. The study results support a larger study using a treat-to-target design to confirm these findings. Clinical trial reg. no. NCT03143816, clinicaltrials.gov .

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.

Postprandial glucose-lowering effect of premeal consumption of protein-enriched, dietary fiber-fortified bar in individuals with type 2 diabetes mellitus or normal glucose tolerance

AIMS/INTRODUCTION

Protein preload improves postprandial glycemia by stimulating secretion of insulin and incretin hormones. However, it requires a large dose of protein to produce a significant effect. The present study was carried out to investigate the postprandial glucose-lowering effect of a premeal protein-enriched, dietary fiber-fortified bar (PFB), which contains moderate amounts of protein, in individuals with type 2 diabetes mellitus or normal glucose tolerance (NGT).

MATERIALS AND METHODS

The participants (15 type 2 diabetes mellitus and 15 NGT) were randomly assigned to either a premeal or postmeal PFB group and underwent two mixed meal tolerance tests, 1 week apart in reverse order. Plasma levels of glucose, insulin, glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide were measured.

RESULTS

During the mixed meal tolerance tests, the incremental area under the curve from 0 to 180 min of plasma glucose levels was lower with premeal PFB than with postmeal PFB in the type 2 diabetes mellitus (14,723 ± 1,310 mg min/dL vs 19,642 ± 1,367 mg min/dL; P = 0.0002) and NGT participants (3,943 ± 416 mg min/dL vs 4,827 ± 520 mg min/dL, P = 0.0296). In the type 2 diabetes mellitus participants, insulinogenic index and the incremental area under the curve from 0 to 180 min of plasma total glucagon-like peptide-1 levels were higher with premeal PFB than with postmeal PFB, but not in the NGT participants. There was no difference in postprandial glucose-dependent insulinotropic polypeptide levels between premeal and postmeal PFB in both groups.

CONCLUSIONS

Acute administration of premeal PFB decreased postprandial glucose excursion in both type 2 diabetes mellitus and NGT participants. In the type 2 diabetes mellitus participants, premeal PFB augmented the early-phase insulin secretion, possibly through enhancing glucagon-like peptide-1 secretion.

Scopoletin inhibits α-glucosidase in vitro and alleviates postprandial hyperglycemia in mice with diabetes

The aim of this study was to investigate whether scopoletin could inhibit the activities of the carbohydrate digestive enzymes, α-glucosidase and α-amylase, and reduce postprandial hyperglycemia in streptozotocin (STZ)-induced diabetes in mice. Scopoletin showed a distinct inhibitory effect on α-glucosidase and α-amylase. The half maximal inhibitory concentration (IC₅₀) of scopoletin was 85.12 and 37.36 μM for α-glucosidase and α-amylase, respectively, which were lower values than those for acarbose. The increase in postprandial blood glucose levels was significantly suppressed in the scopoletin group compared to the control group of STZ-induced diabetes in mice. Moreover, the area under the curve significantly decreased with the administration of scopoletin in STZ-induced diabetes in mice. These results showed that scopoletin might help to lower postprandial hyperglycemia through inhibition of carbohydrate digestive enzymes.

Relative Contribution of Fasting and Postprandial Blood Glucose in Overall Glycemic Control: Post Hoc Analysis of a Phase IV Randomized Trial

INTRODUCTION

Few prospective clinical trials have investigated the role of fasting blood glucose (FBG) and/or postprandial glucose (PPG) in assessing overall glycemic control by using different insulin regimens. In the present post hoc analysis, we assessed the contribution of FBG and/or PPG in overall glycemic control in Chinese patients under insulin treatment.

METHODS

CLASSIFY is a phase IV, randomized, open-label, 26-week, parallel-arm, treat-to-target, multinational, controlled study in patients with type 2 diabetes mellitus to compare the efficacy and safety of insulin lispro mix 25 (LM25) and insulin lispro mix 50 (LM50) as starter insulins. Insulin was titrated with an aim to target pre-meal blood glucose (BG) levels at > 3.9 and ≤ 6.1 mmol/L before breakfast and dinner. The primary outcome assessed was the change in HbA1c from baseline.

RESULTS

Chinese patients contributed 38.7% (N = 156) of the total population. The majority of patients were male (52.6%). The mean (SD) body mass index was 24.54 (3.04) kg/m² and mean (SD) HbA1c was 8.54 (1.10) % at baseline. At week 26, LM50 showed a significantly greater reduction from baseline in HbA1c (- 2.03% vs - 1.55%, P < 0.001), average daily BG (- 3.21 vs - 2.34 mmol/L, P < 0.001), average post-meal BG (- 3.58 vs - 2.39 mmol/L, P < 0.001), and average prandial BG excursion (- 1.01 vs - 0.22 mmol/L, P = 0.006) than the LM25 group. The reductions in average pre-meal BG (- 2.59 vs - 2.28 mmol/L, P = 0.137) were not significantly different between the groups. The proportion of patients achieving HbA1c targets (< 7% or ≤ 6.5%) without nocturnal hypoglycemia or weight gain was greater (P < 0.05) with LM50 compared with LM25.

CONCLUSION

LM50 achieved better overall glycemic control than LM25 as a starter insulin in Chinese patients, which may be due to greater improvement in PPG levels.

TRIAL REGISTRATION

Clinicaltrials.gov identification number: NCT01773473.

FUNDING

Eli Lilly and Company, Shanghai, China.

Antioxidant and anti-glycation capacities of some medicinal plants and their potential inhibitory against digestive enzymes related to type 2 diabetes mellitus

ETHNOPHARMACOLOGICAL RELEVANCE

Plants preparations are used by traditional medicine in the treatment of various diseases, such as type-2 diabetes mellitus. Some medicinal plants are capable of controlling the complications of this metabolic disease at different levels, for example, providing antioxidant compounds that act against oxidative stress and protein glycation and others which are capable of inhibiting the catalysis of digestive enzymes and thus contribute to the reduction of hyperglycemia and hyperlipidemia. Our objective was to investigate the antioxidant and anti-glycation activities of some medicinal plants and their potential inhibitory against α-amylase, α-glucosidase and pancreatic lipase activities.

MATERIAL AND METHODS

Based on the ethnobotanical researches carried out by academic studies conducted at the Federal University of Uberlandia, ten plants traditionally used in the treatment of type-2 diabetes mellitus were selected. Ethanol (EtOH) and hexane (Hex) extracts of specific parts of these plants were used in enzymatic assays to evaluate their inhibitory potential against α-amylase, α-glucosidase and lipase, as well as their antioxidant (DPPH, ORAC and FRAP) and anti-glycation (BSA/fructose model) capacities.

RESULTS

The results indicate that EtOH extract of four of the ten analyzed plants exhibited more than 70% of antioxidant and anti-glycation capacities, and α-amylase and lipase inhibitory activities; no extract was able to inhibit more than 40% the α-glucosidase activity. The EtOH extracts of Bauhinia forficata and Syzygium. cumini inhibited α-amylase (IC₅₀ 8.17 ± 2.24 and 401.8 ± 14.7 μg/mL, respectively), whereas EtOH extracts of B. forficata, Chamomilla recutita and Echinodorus grandiflorus inhibited lipase (IC₅₀ 59.6 ± 10.8, 264.2 ± 87.2 and 115.8 ± 57.1 μg/mL, respectively). In addition, EtOH extracts of B. forficata, S. cumini, C. recutita and E. grandiflorus showed, respectively, higher antioxidant capacity (DPPH IC₅₀ 0.7 ± 0.1, 2.5 ± 0.2, 1.3 ± 0.2 and 35.3 ± 9.0 μg/mL) and anti-glycation activity (IC₅₀ 22.7 ± 4.4, 246.2 ± 81.7, 18.5 ± 2.8 and 339.0 ± 91.0 μg/mL).

CONCLUSIONS

EtOH extracts of four of the ten species popularly cited for treatment of type 2 diabetes mellitus have shown promising antioxidant and anti-glycation properties, as well as the ability to inhibit the digestive enzymes α-amylase and lipase. Thus, our results open new possibilities for further studies in order to evaluate the antidiabetic potential of these medicinal plants.

Chemo-biological evaluation of antidiabetic activity of Mentha arvensis L. and its role in inhibition of advanced glycation end products

Background

There has been enormous curiosity in the development of alternative plant based medicines to control diabetes, oxidative stress and related disorders. One of the therapeutic approaches is to reduce postprandial release of glucose in the blood. Two key enzymes that are involved in reducing postprandial glucose are α-amylase and α-glucosidase. Mentha arvensis L. has been traditionally used by several tribes as a medicinal plant to treat various disorders.

Objective

The present study was undertaken to test M. arvenisis L. for inhibition of postprandial hyperglycemia.

Material and method

We performed various in vitro and in vivo tests to evaluate efficacy of M. arvenisis L. for antidiabetic activity (postprandial hyperglycemia).

Results

Methanolic extract of M. arvensis L. leaves showed DPPH free radical scavenging activity (more than 78% μg/μl) and high antiglycation potential (more than 90% inhibition of AGE formation). Methanolic extract also showed remarkable inhibitory effects on α-amylase (more than 50% μg/μl) and α-glucosidase (68% μg/μl) and significant inhibition of postprandial hyperglycemia in starch induced diabetic Wistar rats.

Conclusion

The non-insulin dependent antidiabetic or inhibition of postprandial hyperglycemic activity of methanolic extract of M. arvensis L. leaves was shown by using in vitro and in vivo approaches in the present study.

Hepatic IRS1 and ß-catenin expression is associated with histological progression and overt diabetes emergence in NAFLD patients

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a risk factor for type 2 diabetes. Our aim was to investigate the relationship between NAFLD and impaired glucose metabolism in terms of insulin receptor substrate 1 and 2 (IRS1 and IRS2) expression in the liver.

METHODS

Liver biopsy was performed at the University of Tokyo Hospital between November 2011 and March 2016 on 146 patients with NAFLD who were not being treated with any diabetes or dyslipidemia drugs. Among them, 63 underwent liver biopsy after an overnight fast, and 83 at 5 h after an oral glucose tolerance test (OGTT). Differences in messenger RNA (mRNA) levels of several glucose metabolism-related factors were determined and correlated with hepatic histological changes assessed by NAFLD activity score. We prospectively followed up with the patients until May 2017.

RESULTS

Hepatic necroinflammation was significantly correlated with serum insulin levels and inversely correlated with IRS1 mRNA levels. In specimens obtained after an OGTT, hepatic necroinflammation and IRS1 expression correlated significantly with both peripheral and hepatic insulin resistance. We also found that hepatic β-catenin and glucokinase mRNA levels were elevated in patients undergoing liver biopsy after an OGTT, especially in those with less hepatic necroinflammation and a lower degree of fibrosis. A prospective cohort study showed that ballooning is the most significant risk factor for developing diabetes.

CONCLUSIONS

The decreased hepatic expression of IRS1 and β-catenin in NAFLD is linked to histological progression such as ballooning, and might lead to diabetes as a result of impaired glucose metabolism.

Anti-hyperglycemic and antioxidant potential of Croton bonplandianus. Bail fractions in correlation with polyphenol content

OBJECTIVES

Diabetes mellitus, a carbohydrate metabolic disorder, occurs due to absolute or relative deficiency of insulin. Current treatment strategies involve either preventing or delaying the intestinal absorption of glucose to lower the levels of postprandial hyperglycemia (PPHG). Herbal remedies have been since ancient times for treating diabetes mellitus. Therefore, identifying novel phytocompounds with α-amylase and α-glucosidase inhibitory activity that would reduce the glucose absorption as well as the rise in postprandial blood glucose level is vital. Consequently, the present study was aimed to investigate the anti-hyperglycemic activity of Croton bonplandianus against these pancreatic enzymes.

MATERIALS AND METHODS

The methanol extract of C. bonplandianus leaf was prepared and further fractionation was performed with n-hexane, ethyl acetate and chloroform. The antioxidant activity and anti-hyperglycemic activity of the extracts and its fractions were determined. Further, GC-MS analysis was performed for the leaf extract.

RESULTS

The chloroform fraction (ChF) was found to contain highest quantity of polyphenols (114.28 µg/ml of GAE), flavonoids (95.68 µg/ml of quercetin) and tannins (63.80 µg/ml of GAE) and also possessed effective inhibitory activity against α amylase (IC₅₀95.78 µg/ml) and α glucosidase (IC₅₀ 126.81µg/ml). The antioxidant activity of ChFwas also higher when compared to other fractions. Further, GC-MS analysis of ChF showed the presence of various components that may be responsible for the above mentioned activities.

CONCLUSION

The study findings suggest that the components present in the leaves of C. bonplandianus, may provide a potential therapeutic source in developing treatment forhyperglycemia. Further bioassay guided fractionation procedure is required to identify the active constituents.

Low 1,5-anhydroglucitol levels are associated with long-term cardiac mortality in acute coronary syndrome patients with hemoglobin A1c levels less than 7.0

BACKGROUND

Diabetes mellitus is considered an important risk factor for cardiovascular diseases. High hemoglobin A1c (HbA1c) levels, which indicate poor glycemic control, have been associated with occurrence of cardiovascular diseases. There are few parameters which can predict cardiovascular risk in patients with well-controlled diabetes. Low 1,5-anhydroglucitol (1,5-AG) levels are considered a clinical marker of postprandial hyperglycemia. We hypothesized that low 1,5-AG levels could predict long-term mortality in acute coronary syndrome (ACS) patients with relatively low HbA1c levels.

METHODS

The present study followed a retrospective observational study design. We enrolled 388 consecutive patients with ACS admitted to the cardiac intensive care unit at the Juntendo University Hospital from January 2011 to December 2013. Levels of 1,5-AG were measured immediately before emergency coronary angiography. Patients with early stent thrombosis, no significant coronary artery stenosis, malignancy, liver cirrhosis, a history of gastrectomy, current steroid treatment, moderately to severely reduced kidney function (estimated glomerular filtration rate < 45 ml/min/1.73 m2; chronic kidney disease stage 3B, 4, and 5), HbA1c levels ≥ 7.0%, and those who received sodium glucose co-transporter 2 inhibitor therapy were excluded.

RESULTS

During the 46.9-month mean follow-up period, nine patients (4.5%) died of cardiovascular disease. The 1,5-AG level was significantly lower in the cardiac death group compared with that in the survivor group (12.3 ± 5.3 vs. 19.2 ± 7.7 µg/ml, p < 0.01). Kaplan-Meier survival analysis showed that low 1,5-AG levels were associated with cardiac mortality (p = 0.02). Multivariable Cox regression analysis showed that 1,5-AG levels were an independent predictor of cardiac mortality (hazard ratio 0.76; 95% confidence interval 0.41-0.98; p = 0.03).

CONCLUSION

Low 1,5-AG levels, which indicate postprandial hyperglycemia, predict long-term cardiac mortality even in ACS patients with HbA1c levels < 7.0%.

Assessing the Therapeutic Utility of Professional Continuous Glucose Monitoring in Type 2 Diabetes Across Various Therapies: A Retrospective Evaluation

BACKGROUND

There have been few large studies that have analyzed the effect of professional (masked) continuous glucose monitoring (P-CGM) on glycemic control in patients with type 2 diabetes (T2DM) who were on a broad spectrum of baseline therapies.

METHODS

We performed a retrospective, blinded evaluation of glycemic control in 296 T2DM adults for 6 months following a 6- to 7-day study of their glycemic profile using masked P-CGM. At baseline, 91% of the patients were on some form of insulin treatment with oral hypoglycemic agents (OHA), while 7% were on one or more OHAs without insulin, and the remaining 2% were on GLP-1RAs. On the basis of the masked CGM profile, patients were counselled on diet and exercise change(s) in their baseline diabetes therapy by our professionally trained diabetes team. They also continued to receive regular treatment advice and dose titrations through our Diabetes Tele-Management System (DTMS^®). The baseline changes in hemoglobin A1C (A1C) observed in these patients after 6 months of undergoing P-CGM was compared to a matched control group.

RESULTS

P-CGM revealed that the predominant pattern of hyperglycemia was postprandial while previously unknown hypoglycemia was found in 38% of the patients; over half of the cases of hypoglycemia were nocturnal. The mean A1C of the P-CGM group dropped from 7.5 ± 1.4% at baseline vs. 7.0 ± 0.9% at 6 months (p < 0.0001). The frequency of performing self-monitoring of blood glucose (SMBG) was also found to be significantly increased in these patients from the baseline. Meanwhile, no significant improvement in A1C was noted in the control group during the same time frame (7.7 ± 1.1% at baseline vs. 7.4 ± 1.1% at 6 months; p = 0.0663) and frequency of SMBG remained almost unchanged.

CONCLUSIONS

P-CGM can provide actionable data and motivate patients for diabetes self-care practices, resulting in an improvement in glycemic control over a wide range of baseline therapies.