Synthesis, biological evaluation and action mechanism of 7H-[1,2,4] triazolo [3,4-b] [1,3,4] thiadiazine-phenylhydrazone derivatives as α-glucosidase inhibitors

In our work, several 7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine-phenylhydrazone derivatives as α-glucosidase inhibitors (α-GIs) were synthesized and characterized by 1H NMR, 13C NMR, and HRMS spectrum. Then, their bio-activity against the α-glucosidase (α-Glu) was further evaluated. Among them, almost all compounds displayed better bio-activity with IC50 from 31.23 ± 0.89 to 213.50 ± 4.19 μM than acarbose (IC50 = 700.20 ± 10.55 μM). In particular, compound 5o showed the best potency to inhibit α-Glu in a mixed manner. Moreover, the action mechanisms of 5o were further clarified including fluorescence quenching, circular dichroism spectra, three-dimensional fluorescence spectra, molecular docking, etc. All mechanism studies revealed that 5o could arouse the changed secondary structure of α-Glu to hinder enzyme catalytic activity. It was observed from an in vivo study that 5o of 20 mg/kg could significantly decrease by 24.45 % postprandial blood glucose in mice vs. the control. Meanwhile, 5o had low drug-drug interaction potential and was likely to be an orally active compound. Moreover, 5o was observed to be no obvious cytotoxicity to HEK-293 cells. In summary, compound 5o exhibited one potential to be further applied as an antidiabetic drug.

Utilizing bio-affinity ultrafiltration combined with UHPLC Q-Exactive Plus Orbitrap HRMS to detect potential α-glucosidase inhibitors in Oxalis corniculate L

Oxalis corniculate L. (O. corniculate) was used to treat diabetes in Chinese folk as a popular tea drink. In this work, 31 compounds from O. corniculate were screened and identified as potential α-Glucosidase inhibitors (α-GIs). Among them, 6 compounds displayed stronger inhibitory activity than acarbose (IC50 = 212.9 ± 5.98 μg/mL). Especially, the most effective compounds quercetin (Qu, IC50 = 4.70 ± 0.40 μg/mL) and luteolin (Lu, IC50 = 15.72 ± 0.75 μg/mL) inhibited α-Glu in competitive and mixed manners, respectively. Moreover, fluorescence quenching, circular dichroism (CD), and molecular docking study revealed that they can arouse the changes in the secondary structure and hydrophobic micro-environment of the enzyme mainly through a hydrophobic binding. Furthermore, it was observed that oral administration of Qu (20 mg/kg) can significantly reduce postprandial blood glucose (PBG) levels in mice vs. the control group. To sum up, the above research confirmed that O. corniculate could prevent and treat postprandial hyperglycemia as a good tea drink, and the plant was an excellent source to obtain natural α-GIs.

Inhibitory activities and rules of plant gallotannins with different numbers of galloyl moieties on sucrase, maltase and α-amylase in vitro and in vivo

BACKGROUND

α-Glucosidase inhibitors could effectively reduce postprandial blood glucose (PBG) levels and control the occurrence of complications of diabetes. Gallotannins (GTs) in plants have attracted much attention due to their significant α-glucosidase inhibitory activities in vitro. However, there is still a lack of systematic comparative studies to further elucidate inhibitory activities in vivo and in vitro of these compounds against α-glucosidase, especially for mammalian sucrase and maltase, and analyze their structure-activity relationship.

PURPOSE

Determine the in vitro and in vivo inhibitory activities of five GTs with different number of galloyl moieties (GMs) on sucrase, maltase and α-amylase, and elucidate the relationship between α-glucosidase inhibitory activities and the number and connection mode of GMs.

METHODS

Molecular docking and dynamics were used to study the binding mode and binding ability of five GTs against sucrase, maltase and α-amylase. Then, the inhibitory activities and inhibitory mechanisms of these compounds on sucrase, maltase and α-amylase in vitro were studied using inhibitory assay and enzyme inhibition kinetics. Further, the hypoglycemic effects in vivo of these compounds were demonstrated by three polysaccharides tolerance experiments on diabetes model mice.

RESULTS

The results of molecular docking showed that these compounds could bind to enzymes through hydrogen bonds, hydrophobic interactions, etc. In addition, the α-glucosidase inhibition comparative studies in vitro and in vivo demonstrated that the inhibitory activities of these compounds on all three sucrase, maltase and α-amylase were ranked as TA ≈ PGG > TeGG > TGG > 1GG, and their inhibitory activities increases with the increase in the number of GMs. Moreover, the hypoglycemic effects of 1,2,3,4,6-pentagalloylglucose (PGG) and tannic acid (TA) in vitro and in vivo were also confirmed to be equivalent to or even stronger than that of acarbose.

CONCLUSION

α-Glucosidase inhibitory activities in vitro and in vivo of GTs were positively correlated with the number of GTs, and the more the number, the stronger the activity. However, PGG with five GTs and TA with ten GTs showed almost identical α-glucosidase inhibitory activities, possibly due to the reduced binding force with the enzyme caused by spatial hindrance.

Physicochemical characterizations, α-amylase inhibitory activities and inhibitory mechanisms of five bacterial exopolysaccharides

Inhibiting pancreatic α-amylase activity can decrease the release rate of glucose, thereby delaying postprandial blood glucose. This study aimed to investigate the physicochemical properties and porcine pancreatic α-amylase (PPA) inhibitory activities of five bacterial exopolysaccharides (EPSs). We also aimed to analyze the differences of their inhibitory activities, exploring the inhibition mechanism between EPSs and PPA. Five EPSs had a low molecular weight (55-66 kDa), which were mainly composed of mannose and glucose with total content exceeding 86 %. The IC50 values of five EPSs (0.162-0.431 mg/mL) were significantly lower than that of acarbose (0.763 mg/mL), indicating that the inhibitory effects of five EPSs on PPA were stronger than acarbose, especially the EPS from Bacillus subtilis STB22 (BS-EPS). Moreover, BS-EPS was a mixed-type inhibitor, whereas other EPSs were noncompetitive inhibitors of PPA. Five EPSs quenched the fluorophore of PPA by the mixed quenching or apparent static quenching. Interestingly, BS-EPS showed stronger binding affinity to PPA than other EPSs. It can be speculated that EPSs with low molecular weight, high carboxylic acid content, and α-glycosidic bond exhibited high PPA inhibitory activity. These results suggest that BS-EPS can effectively inhibit PPA activity and has potential applications in reducing postprandial hyperglycemia.

Determinants of blood glucose concentrations following a high carbohydrate meal in type 2 diabetes: A multiple linear regression analysis

This study showed that in relatively well-controlled type 2 diabetes blood glucose levels after a high carbohydrate meal were associated positively with fasting blood glucose, but also positively with gastric emptying in the first hour and negatively with the increments in plasma glucagon-like peptide-1 (GLP-1) in the later postprandial phase.

fruits and its effect on regulating postprandial blood glucose

Melastoma dodecandrum Lour. (MDL) extracts have shown potent α-glucosidase inhibitory activity, suggesting MDL might be a good source of α-glucosidase inhibitors. The aim of the study was to identify compounds in MDL extracts with α-glucosidase inhibitory activities and evaluate their effect on postprandial blood glucose as well as elucidating the underlying mechanisms of inhibition. A total of 34 polyphenols were identified in MDL fruits, among which 10 anthocyanins and three proanthocyanidin derivatives were discovered for the first time. Dosing mice with MDL extracts (100 mg/kg body weight, by gavage) was associated with a significantly decrease in postprandial blood glucose concentrations after oral administration of maltose. The most potent α-glucosidase inhibitor was identified as casuarictin (IC₅₀ of 0.21 μg/mL). Casuarictin bound competitively to α-glucosidase, occupying not only the catalytic site but also forming strong hydrogen bonds with α-glucosidase residues. Therefore, casuarictin derived from MDL fruits might be used as novel α-glucosidase inhibitor in functional foods or other dietary products.

Association Between Time in Range and Postprandial Glucose Contribution Rate in Non-Insulin-Treated Type 2 Diabetes Patients: Inverse Correlation of Time in Range with Postprandial Glucose Contribution Rate

Background: Whether time in range (TIR), a parameter derived from continuous glucose monitoring (CGM), is a marker of postprandial hyperglycemia remains to be determined. In this study, we examined the association between TIR and postprandial glucose in non-insulin-treated type 2 diabetic patients. Methods: Our cross-sectional study included 729 non-insulin-treated patients with type 2 diabetes who underwent CGM without any changes in drug therapy on admission. The 24-h CGM record was analyzed for average glucose, standard deviation, percentage coefficient of variation, time above range, TIR, time below range, area under the curve (AUC) of basal glucose, AUC of postprandial glucose, and postprandial glucose contribution rate (%). The primary endpoint was the association between TIR and the postprandial glucose contribution rate. Results: We made TIR groups divided into 10% increments for a 7-group and compared with <40% to >90%. The basal and postprandial glucose AUCs correlated negatively with TIR. The postprandial glucose contribution rate correlated with TIR. The cutoff value for TIR, where postprandial glucose contribution rate was lower than the basal glucose contribution rate, was 66.3%. Conclusions: In non-insulin-treated type 2 diabetic patients, postprandial glucose AUC was higher in the high TIR group, whereas the basal glucose AUC was higher in the low TIR group. Good glycemic control can be achieved with therapeutic interventions that target postprandial glucose and basal glucose in patients with TIR ≥66.3% and <66.3%, respectively. University Medical Information Network [UMIN] ID: UMIN0000254333.

A Comparison of Postprandial Glucose Control in the Medtronic Advanced Hybrid Closed-Loop System Versus 670G

Background: We recently reported that use of an "advanced" hybrid closed-loop system reduced hyperglycemia without increasing hypoglycemia compared to a first-generation system. The aim of this analysis was to evaluate whether this improved performance was specifically related to better mealtime glycemic control. Methods: We conducted a secondary analysis of postprandial glycemic control in an open-label, multinational, randomized crossover trial of 112 participants with type 1 diabetes, aged 14-29, of the Medtronic MiniMed™ 670G hybrid closed-loop system (670G) versus the Medtronic advanced hybrid closed-loop (AHCL) system, for 12 weeks each. We compared glycemic and insulin delivery metrics over a 3 h horizon across all meals to assess system performance and outcomes. Results: Overall meal size and premeal insulin on board were similar during run-in and between 670G and AHCL arms. Compared with 670G arm, premeal, peak, and mean glucose levels were numerically lower in the AHCL arm (167 ± 23, 231 ± 23, and 177 ± 20 mg/dL vs. 175 ± 23, 235 ± 23, and 180 ± 19 mg/dL, respectively), with a trend to lower hyperglycemia level 2 in AHCL arm. Adjusting for premeal glucose level, all postmeal outcomes between 670G and AHCL were statistically similar. Prandial insulin delivery also was similar in both treatment arms (21 ± 9 vs. 23 ± 10 U), with a shift in basal/bolus ratio from 28%/71% in 670G arm to 20%/80% in AHCL arm. Conclusions: Reduced hyperglycemia with AHCL compared to 670G was not related to early postprandial glycemic excursions after adjusting for premeal glucose level (<3 h after meal), but likely to later (>3 h) postprandial or overnight improvements. Further refinements to mealtime bolus algorithms and strategies may more optimally control prandial glycemic excursions.

Impact of low-starch high-fiber pasta on postprandial blood glucose

BACKGROUND AND AIMS

Almost all of the energy in noodle dishes is derived from carbohydrates, particularly starch. Recently, we invented a pasta with reduced starch content to about 50% and increased dietary fiber content, designated low-starch high-fiber pasta (LSHFP). In this study, we investigated the ingestion of LSHFP on the postprandial glucose response as a breakfast meal.

METHODS AND RESULT

This was a randomized, single-blinded, crossover study. The postprandial glucose area under the curve for 4 h (4h-gluAUC), as the primary outcome, and the extent of postprandial glucose elevation (maxΔBG) were evaluated using a continuous glucose monitoring system in healthy volunteers and patients with type 2 diabetes (T2DM) after intake of LSHFP, standard pasta (SP), and rice. The amount of total carbohydrate was matched between LSHFP and SP. Ten individuals with T2DM and 10 individuals who did not have T2DM and were otherwise healthy were enrolled in this crossover study. The 4h-gluAUC for LSHFP (137.6 ± 42.2 mg/dL・h) was significantly smaller than the 4h-gluAUC for rice (201.7 ± 38.7 mg/dL・h) (p = 0.001) and SP (178.5 ± 59.2 mg/dL・h) (p = 0.020). The maxΔBG for rice (118.6 ± 24.2 mg/dL) was significantly higher than those for SP (87.5 ± 19.9 mg/dL) (p < 0.001) and LSHFP (72.7 ± 26.2 mg/dL) (p = 0.001), while the maxΔBG for LSHFP (p = 0.047) was significantly lower than that for SP, in T2DM patients as well as in healthy participants.

CONCLUSIONS

This study demonstrated that LSHFP can reduce postprandial glucose elevation compared with SP in both healthy participants and patients with T2DM.

Continuous Glucose Monitoring Sensor Glucose Levels and Insulin Pump Infusion Set Wear-Time During Treatment with Fast-Acting Insulin Aspart: A Post Hoc Analysis of Onset 5

Background: In the onset 5 trial, fast-acting insulin aspart (faster aspart) was noninferior to insulin aspart (IAsp) for change from baseline glycated hemoglobin at 16 weeks, when used in continuous subcutaneous insulin infusion by participants with type 1 diabetes. The aim of this post hoc analysis was to investigate whether infusion set wear-time was associated with changes in sensor glucose, measured using continuous glucose monitoring (CGM). Materials and Methods: This was a post hoc analysis of onset 5 data. Mean infusion set wear-time and duration of CGM-wearing period were assessed. Mean CGM sensor glucose 24 h before and 24 h after were used to calculate the before-after difference (CGM sensor glucose drift). Results: Mean infusion set wear-time was 2.9 and 3.0 days in the faster aspart and IAsp arms, respectively. At 16 weeks, the average duration of the CGM wearing period was 13.7 and 13.8 days, respectively. Mean CGM sensor glucose before versus after an infusion set change, at week 16, was 10.14 versus 9.39 mmol/L with faster aspart and 9.48 versus 9.47 mmol/L with IAsp. The estimated treatment difference in CGM sensor glucose drift at 16 weeks for faster aspart versus IAsp was +0.72 mmol/L (95% confidence interval: 0.48-0.96, P < 0.001). Conclusions: Mean infusion set wear-time and duration of CGM-wearing period were similar for faster aspart and IAsp. A significantly greater upward drift in CGM sensor glucose values measured during an infusion set wearing period was observed with faster aspart versus IAsp. Clinical trial registration: NCT02825251.

Gut Microbiome Activity Contributes to Prediction of Individual Variation in Glycemic Response in Adults

Limiting postprandial glycemic response (PPGR) is an important intervention in reducing the risk of chronic metabolic diseases and has been shown to impart significant health benefits in people with elevated levels of blood sugar. In this study, we collected gut microbiome activity data by assessing the metatranscriptome, and we measured the glycemic responses of 550 adults who consumed more than 30,000 meals, collectively, from omnivore or vegetarian/gluten-free diets. We demonstrate that gut microbiome activity, anthropometric factors, and food macronutrients modulate individual variation in glycemic response. We employ two predictive models, including a mixed-effects linear regression model (R = 0.77) and a gradient boosting machine model (Rtrain = 0.80/R2train = 0.64; Rtest = 0.64/R2test = 0.40), which demonstrate variation in PPGR between individuals when ingesting the same foods. All features in the final mixed-effects linear regression model were significant (p < 0.05) except for two features which were retained as suggestive: glutamine production pathways (p = 0.08) and the interaction between tyrosine metabolizers and carbs (p = 0.06). We introduce molecular functions as features in these two models, aggregated from microbial activity data, and show their statistically significant contributions to glycemic control. In summary, we demonstrate for the first time that metatranscriptomic activity of the gut microbiome is correlated with PPGR among adults.

Alkaloids and phenolics identification in fruit of Nitraria tangutorum Bobr. by UPLC-Q-TOF-MS/MS and their a-glucosidase inhibitory effects in vivo and in vitro

Nitraria tangutorum Bobr. (NTB), mainly distributed in the Qaidam Basin of Tibetan Plateau, have high economic, ecological and medicinal value. The chemical compositions in the NTB fruits were tentatively analyzed and characterized by applying UPLC-Q-TOF-MS/MS. Total 45 constituents, including 9 hydroxycinnamic acids derivatives, 12 flavonols, 4 flavonoids, 1 trolox derivative, 8 β-carboline alkaloids, 4 tryptophan derivatives, and 7 other amino acid derivatives were identified by comparing with standard products, and analyzing their retention times, characteristic fragment ions and deprotonated molecule ions. The activity studies in vitro indicated that NTB-Z and NTB-C extracts had marked inhibitory effects against sucrase and maltase. Further sucrose/maltose/starch tolerance experiment demonstrated that both NTB-Z and NTB-C extracts at 400 mg/kg could markedly lower the postprandial blood glucose (PBG) level in diabetic animals. All these results indicated that the NTB fruits could be used as the functional health food or medicine for controlling postprandial blood glucose level.

Adjunctive vitamin A and D for the glycaemic control in patients with concurrent type 2 diabetes and tuberculosis: a randomised controlled trial

The objective of this study is to investigate the effects of vitamin A, D and their interaction on the glycaemic control in patients with both diabetes and tuberculosis. Tuberculosis infection and its treatment induce hyperglycaemia and complicate the glycaemic control in patients with diabetes. A randomised controlled trial with a 2 × 2 factorial design was conducted in a tuberculosis-specialised hospital in Qingdao, China. A total of 279 patients who have both diabetes and tuberculosis were included in this analysis. The patients received standard anti-tuberculosis treatment alone (control group), or together with a dose of vitamin A (600 μg RAE/d) or vitamin D (10 μg/d) or a combination of vitamin A (600 μg RAE/d) and vitamin D (10 μg/d) for 2 months. The effects of the intervention on fasting plasma glucose and 2-h postprandial blood glucose were investigated by ANCOVA. The analysis was adjusted for baseline values, age, sex, smoking, drinking and antidiabetic treatment as covariates. No significant effect was observed for vitamin A and D supplementation on fasting plasma glucose, 2-h postprandial blood glucose, BMI and related blood parameters. No interaction was observed between vitamin A and D supplementation for these endpoints. Vitamin A and D supplementation showed a null effect on the glycaemic control for patients with concurrent diabetes and tuberculosis. Future work should evaluate the effect of vitamin A and D supplementation on insulin-related indices for these patients and investigate the effect of vitamin D receptor genotypes.

Bioactive flavonoids from Rubus corchorifolius inhibit α-glucosidase and α-amylase to improve postprandial hyperglycemia

This research established an optimized method for the extraction and enrichment of flavonoids from R. corchorifolius fruit. Under the optimized extraction conditions, 12 flavonoids (1-12) were isolated, of which six (2-4, 9-10, 12) were obtained from R. corchorifolius for the first time. Compound 4 showed significant α-glucosidase (4.96 μM) and α-amylase (8.04 μM) inhibitory effects. Molecular modeling revealed that compound 4 exhibits strong binding with the active sites of α-glucosidase and α-amylase. Lineweaver-Burk plot analysis and surface plasmon resonance revealed the possible dynamic binding mechanism of the flavonoids with α-glucosidase and α-amylase. The enriched flavonoids and compound 4 showed significant hypoglycemic effects in mice administered a high dose of glucose. In this study, a variety of flavonoids with hypoglycemic activity were found for the first time, revealing the rich chemical composition of R. corchorifolius fruit and highlighting the potential value of R. corchorifolius fruit flavonoids as dietary supplements.

Glycemic indices of dates "Ramadan Symbolic Food" in patients with type 2 diabetes using continuous glucose monitoring system

AIM

The high consumption of dates during Ramadan raises the question about its glycemic index (GI) and its effect on the glycemic control in patients with type 2 diabetes (T2DM). We aimed to determine the GI of varieties of meals containing dates in healthy subjects compared to patients with T2DM and the effect of dates on the postprandial glucose excursions using continuous glucose monitoring system (CGMS).

METHOD AND RESULTS

Twenty patients with T2DM and twenty healthy subjects matched for age, sex and body weight participated. Testing was applied on separate days (on 3 occasions) with 50 g of glucose and 50 g equivalent of available carbohydrates from 9 date meals. The GI was calculated as ratios of the incremental areas under the response curves for dates in comparison to glucose. Minimed-530 g-diabetes-system-with-enlite was used for continuous glucose monitoring. There was no significant difference between the mean GI of dates between both study groups. However, there was a significant difference according to the time of peak blood glucose among varieties of meals containing dates in T2DM.

CONCLUSION

Studied varieties of dates have low GI. CGMS valued beyond GI calculation to study the postprandial glucose excursions among patients with T2DM.

Identification of phenolic compounds in fruits of Ribes stenocarpum Maxim. By UHPLC-QTOF/MS and their hypoglycemic effects in vitro and in vivo

The gooseberry (Ribes stenocarpum Maxim. (CBZ)) is a wild and noncommercially cultivated berry fruit widely distributed in the Tibetan Plateau. The phenolic constituents from the berry fruit of CBZ were firstly identified by employing UPLC-QTOF MS. A total of 41 compounds, including hydroxycinnamic acids, hydroxybenzoic acids, flavonols and dihydroflavonol, were identified in view of their molecular weight, characteristic fragment ions and retention times. Further in vitro enzyme assay indicated that CBZ fruit extract could strongly and effectively inhibited a-glucosidase and α-amylase, with the IC₅₀ values of 0.013 mg/mL and 0.005 mg/mL, respectively. In addition, the starch/maltose/sucrose tolerance experiment demonstrated that the CBZ fruit extract could reduce the sucrose mediated postprandial blood glucose (PBG) levels in normal mice, and significantly lower starch/maltose/ sucrose mediated PBG levels in diabetic mice. These results suggested that this berry fruit could be used as a dietary supplement, or drug for the control of hyperglycemia.

Daily consumption of one teaspoon of trehalose can help maintain glucose homeostasis: a double-blind, randomized controlled trial conducted in healthy volunteers

Background

Trehalose is a natural disaccharide that is widely distributed. A previous study has shown that daily consumption of 10 g of trehalose improves glucose tolerance in individuals with signs of metabolic syndrome. In the present study, we determined whether a lower dose (3.3 g/day) of trehalose improves glucose tolerance in healthy Japanese volunteers.

Methods

This was a randomized, double-blind, placebo-controlled study of healthy Japanese participants (n = 50). Each consumed 3.3 g of trehalose (n = 25) or sucrose (n = 25) daily for 78 days. Their body compositions were assessed following 0, 4, 8, and 12 weeks; and serum biochemical parameters were assayed and oral 75-g glucose tolerance tests were performed at baseline and after 12 weeks.

Results

There were similar changes in body composition and serum biochemistry consistent with established seasonal variations in both groups, but there were no differences in any of these parameters between the two groups. However, whereas after 12 weeks of sucrose consumption, the plasma glucose concentration 2 h after a 75-g glucose load was significantly higher than the fasting concentration, after 12 weeks of trehalose consumption the fasting and 2-h plasma glucose concentrations were similar. Furthermore, an analysis of the participants with relatively high postprandial blood glucose showed that the plasma glucose concentration 2 h after a 75-g glucose load was significantly lower in the trehalose group than in the sucrose group.

Conclusions

Our findings suggest that trehalose helps lower postprandial blood glucose in healthy humans with higher postprandial glucose levels within the normal range, and may therefore contribute to the prevention of pathologies that are predisposed to by postprandial hyperglycemia,, even if the daily intake of trehalose is only 3.3 g, an amount that is easily incorporated into a meal.

Trial registration

UMIN, UMIN000033536. Registered 27 July 2018.

Drinking water with consumption of a jelly filled doughnut has a time dependent effect on the postprandial blood glucose level in healthy young individuals

An elevated postprandial glucose (PPG) level in plasma or blood is a risk factor for chronic disorders like obesity, diabetes mellitus type II and related cardiovascular conditions. Therefore, it is important to identify mechanisms that increase the value of postprandial glucose PPG levels. Hence in the present study we investigated the time dependent effect of drinking water during a meal on the level of PPG. Thirty-five volunteers were randomly assigned to five groups. Group A was given a jelly filled doughnut and group B, C, D and E had a similar doughnut in combination with a bottle of water along with the doughnut, thirty minutes before, thirty minutes after, and a second doughnut with water thirty minutes after the first one, respectively. Glucose was measured in capillary blood at intervals of 30 min up to 150 min (reg # FMeW 725B/17). PPG versus fasting glucose (Means ± SD, mmol/L) was for group A 5.4 ± 0.6 vs 4.6 ± 0.4, B 7.2 ± 0.7 vs 4.9 ± 0.4, C 5.5 ± 0.7 vs 4.4 ± 0.3, D 5.5 ± 0.6 vs 4.6 ± 0.3 and E 5.7 ± 0.5 vs 4.7 ± 0.2. The increase in group B was significantly higher than in all other groups (ANOVA, Dunnet's posttest). These results show that drinking water with consumption of a jelly-filled doughnut increases the postprandial blood glucose levels significantly compared to no drinking at all or thirty minutes before or after the consumption. It is therefore advisable that we should reconsider our eating and drinking habits to lower the PPG and consequently reduce the risks of abovementioned chronic disorders. Further assessment is necessary to evaluate this in more detail.

Baseline type 2 diabetes had a significant association with elevated high sensitivity cardiac troponin T levels in Chinese community-dwelling population: a 5-year prospective analysis

Background

The present analysis was designed to investigate the association of type 2 diabetes (T2D) with high sensitivity cardiac troponin T (hs-cTnT) during the 5 years of follow-up, and explore which one of fasting blood glucose (FBG) and postprandial blood glucose (PBG) is a determinant of this association in Chinese community-dwelling population.

Methods

This prospective community-based analysis was conducted based on 730 participants without coronary artery disease and hs-cTnT values ≥14 pg/mL receiving two measurements of hs-cTnT levels at baseline and follow-up of 5 years.

Results

Prevalence of T2D was 16.2% (118 participants). Median hs-cTnT levels were 4 (3-7) pg/mL and 6 (5-9) pg/mL at baseline and follow-up, respectively. The variation in hs-cTnT levels had a median of 2 (0-4) pg/ml (p < 0.001 for variation), and incidence of hs-cTnT levels ≥14 pg/ml was 7.1% (52 participants) at follow-up. T2D had a significant association with elevated hs-cTnT levels in multivariate Logistic regression models (p < 0.05). Elevated levels of PBG (p < 0.05) rather than FBG (p > 0.05) determined the significant association with elevated hs-cTnT levels in multivariate linear regression models.

Conclusions

This community-based analysis observed that there was a significant increment of hs-cTnT levels, and baseline T2D had a significant association with elevated hs-cTnT levels during the 5 years of follow-up. Moreover, the present analysis demonstrated that PBG rather than FBG played a crucial role in this association in Chinese community-dwelling population without CAD.

Closed-Loop Control Without Meal Announcement in Type 1 Diabetes

OBJECTIVE

A fully closed-loop insulin-only system was developed to provide glucose control in patients with type 1 diabetes without requiring announcement of meals or activity. Our goal was to assess initial safety and efficacy of this system.

RESEARCH DESIGN AND METHODS

The multiple model probabilistic controller (MMPPC) anticipates meals when the patient is awake. The controller used the subject's basal rates and total daily insulin dose for initialization. The system was tested at two sites on 10 patients in a 30-h inpatient study, followed by 15 subjects at three sites in a 54-h supervised hotel study, where the controller was challenged by exercise and unannounced meals. The system was implemented on the UVA DiAs system using a Roche Spirit Combo Insulin Pump and a Dexcom G4 Continuous Glucose Monitor.

RESULTS

The mean overall (24-h basis) and nighttime (11 PM-7 AM) continuous glucose monitoring (CGM) values were 142 and 125 mg/dL during the inpatient study. The hotel study used a different daytime tuning and manual announcement, instead of automatic detection, of sleep and wake periods. This resulted in mean overall (24-h basis) and nighttime CGM values of 152 and 139 mg/dL for the hotel study and there was also a reduction in hypoglycemia events from 1.6 to 0.91 events/patient/day.

CONCLUSIONS

The MMPPC system achieved a mean glucose that would be particularly helpful for people with an elevated A1c as a result of frequent missed meal boluses. Current full closed loop has a higher risk for hypoglycemia when compared with algorithms using meal announcement.

Effects of 1,5-anhydroglucitol on postprandial blood glucose and insulin levels and hydrogen excretion in rats and healthy humans

The inhibition by 1,5-anhydro-d-glucitol (1,5-AG) was determined on disaccharidases of rats and humans. Then, the metabolism and fate of 1,5-AG was investigated in rats and humans. Although 1,5-AG inhibited about 50 % of sucrase activity in rat small intestine, the inhibition was less than half of d-sorbose. 1,5-AG strongly inhibited trehalase and lactase, whereas d-sorbose inhibited them very weakly. 1,5-AG noncompetitively inhibited sucrase. The inhibition of 1,5-AG on sucrase and maltase was similar between humans and rats. 1,5-AG in serum increased 30 min after oral administration of 1,5-AG (600 mg) in rats, and mostly 100 % of 1,5-AG was excreted into the urine 24 h after administration. 1,5-AG in serum showed a peak 30 min after ingestion of 1,5-AG (20 g) by healthy subjects, and decreased gradually over 180 min. About 60 % of 1,5-AG was excreted into the urine for 9 h following ingestion. Hydrogen was scarcely excreted in both rats and humans 24 h after administration of 1,5-AG. Furthermore, 1,5-AG significantly suppressed the blood glucose elevation, and hydrogen excretion was increased following the simultaneous ingestion of sucrose and 1,5-AG in healthy subjects. 1,5-AG also significantly suppressed the blood glucose elevation following the simultaneous ingestion of glucose and 1,5-AG; however, hydrogen excretion was negligible. The available energy of 1,5-AG, which is absorbed readily from the small intestine and excreted quickly into the urine, is 0 kJ/g (0 kcal/g). Furthermore, 1,5-AG might suppress the blood glucose elevation through the inhibition of sucrase, as well as intestinal glucose absorption.

Apple and blackcurrant polyphenol-rich drinks decrease postprandial glucose, insulin and incretin response to a high-carbohydrate meal in healthy men and women

Postprandial glycemic responses to meals are inhibited by polyphenol-rich plant foods. Combinations of polyphenols may be particularly effective through complementary mechanisms. A randomized, controlled, double-blinded cross-over trial was conducted in healthy volunteers to test the hypothesis that apple and blackcurrant polyphenol-rich drinks would reduce postprandial blood glucose concentrations. Secondary outcomes included insulin and glucose-dependent insulinotropic polypeptide (GIP) secretion. Twenty men (mean age 26 y, SD 8) and 5 postmenopausal women (mean age 57 y, SD 3) consumed a placebo drink (CON) and 2 polyphenol-rich drinks containing fruit extracts: either 1200 mg apple polyphenols (AE), or 600 mg apple polyphenols+600 mg blackcurrant anthocyanins (AE+BE), in random order with a starch and sucrose meal. Incremental areas under the curve (iAUC) for plasma glucose concentrations were lower following AE+BE over 0-30 and 0-120 min compared with CON; mean differences (95% CI) -32 mmol/L·min (-41, -22, P<.0005) and -52 mmol/L min (-94, -9, P<.05), respectively. AE significantly reduced iAUC 0-30 min (mean difference -26 mmol/L min, -35, -18, P<.0005) compared with CON, but the difference over 120 min was not significant. Postprandial insulin, C-peptide and GIP concentrations were significantly reduced relative to CON. A dose response inhibition of glucose transport was demonstrated in Caco-2 cells, including total and GLUT-mediated transport, and SGLT1-mediated glucose transport was strongly inhibited at all doses in Xenopus oocytes, following 10 min incubation with 0.125-4 mg apple polyphenols/ml. In conclusion, ingestion of apple and blackcurrant polyphenols decreased postprandial glycemia, which may be partly related to inhibition of intestinal glucose transport.

Divided consumption of late-night-dinner improves glycemic excursions in patients with type 2 diabetes: A randomized cross-over clinical trial

AIMS

To explore the acute effect of late-night-dinner and divided dinner on postprandial glucose levels in patients with type 2 diabetes.

METHODS

Sixteen patients were randomly assigned to this cross-over study. Each patient wore a continuous glucose monitor for 5days and consumed identical test meals for 3days. Patients consumed the test meals of dinner at 2100h (D21) or divided dinner (vegetable and rice at 1800h and the vegetable and the main dish at 2100h) on the second or fourth day, and dinner at 1800h (D18) on the third day. The daily glucose parameters were compared within-patient for 3days.

RESULTS

D21 demonstrated significantly higher values of incremental area under the curve (IAUC) for glucose 2300 to 0800h (644±156vs. 147±63mmol/L×min, p<0.01, mean±standard error of the mean) and incremental glucose peak (IGP) after dinner (6.78±0.79 vs. 3.09±0.62mmol/L, p<0.01) compared to those of D18. Moreover, the mean amplitude of glycemic excursion (MAGE) of D21 tended to be higher than that of D18 (6.99±0.60 vs. 5.35±0.51mmol/L, p=0.077). However, the divided dinner significantly reduced IAUC 2300 to 0800h (142±60mmol/L×min, p<0.01), IGP after dinner (3.75±0.58mmol/L, p<0.01), and MAGE (5.33±0.41mmol/L, p<0.01) compared to those of D21.

CONCLUSION

Our findings demonstrated that consuming late-night-dinner led to postprandial hyperglycemia, and this postprandial hyperglycemia can be ameliorated by consuming a divided dinner.

Combination of flavonoids from Oroxylum indicum seed extracts and acarbose improves the inhibition of postprandial blood glucose: In vivo and in vitro study

The combined effect of Oroxylum indicum seed extracts (OISE) or major flavonoids from OISE and acarbose on reducing postprandial blood glucose (PBG) levels was investigated in vitro and in vivo. In vitro, the IC₅₀ values of OISE and baicalein against α-glucosidase were 43.4±0.731μgmL^-1 and 25.9±0.412μgmL^-1 respectively. A combination of acarbose with OISE or baicalein synergistically inhibited rat intestinal α-glucosidase. The combination index (CI) values for acarbose with OISE ranged from 0.33 to 0.75, suggesting a synergistic but not additive effect. OISE was determined to be a non-competitive inhibitor of maltose-hydrolyzing activity. In vivo, OISE were administered to normoglycemic and diabetic mice, either alone or in combination with acarbose. At doses between 50 and 200mgkg^-1, OISE enhanced the efficacy of acarbose by up to 5-fold. These results demonstrated that OISE enhances the efficacy of acarbose in vivo, and that the combination of OISE and acarbose displayed a synergistic effect in vitro. Therefore, OISE can be used to design dietary supplements to treat diabetes.

Impact of postprandial hyperglycemia at clinic visits on the incidence of cardiovascular events and all-cause mortality in patients with type 2 diabetes

Aims/Introduction

We evaluated the impact of postprandial hyperglycemia at clinic visits on the incidence of cardiovascular diseases (CVD) and all‐cause mortality independently of mean glycosylated hemoglobin in type 2 diabetes patients in a real‐world setting.

Materials and Methods

The present retrospective observational cohort study included 646 type 2 diabetes patients. All of the participants had their initial consultations at the Institute for Diabetes Care and Research, Asahi Life Foundation affiliated Marunouchi Hospital, Tokyo, Japan, during the period from 1995 to 1996, visited the clinic ≥4 times, had their 2‐h post‐breakfast blood glucose (2h‐PBBG) levels measured and were followed up for ≥1 year. The 646 patients were followed up for survival. Of the 646 patients, 618 had no history of CVD at the first visit and had measured 2h‐PBBG until the first CVD onset or censorings. These two cohorts were followed up through June 2012, and subsequently questionnaires were mailed. Multivariate Cox proportional hazard models were used to evaluate the risk of CVD incidence and death.

Results

CVD occurred in 78 patients, and 56 patients died. The median follow‐up periods of the CVD cohort and the mortality cohort were 15.6 and 15.9 years, respectively. The mean 2h‐PBBG is a significant predictor of the CVD incidence and all‐cause mortality after adjusting for the mean glycosylated hemoglobin, the number of 2h‐PBBG measurements, age, sex and classical risk factors.

Conclusions

Postprandial hyperglycemia represented by the mean level of 2h‐PBBG at clinic visits is associated with CVD incidence and all‐cause mortality independently of the mean glycosylated hemoglobin level in type 2 diabetes patients. Prospective interventional trials are warranted to confirm the present findings.

Roles of fasting and postprandial blood glucose in the effect of type 2 diabetes on central arterial stiffness: a 5-year prospective community-based analysis

BACKGROUND

Cardiovascular disease constitutes a major challenge for the health of community-dwelling population, it is essential to delay the development of atherosclerosis. However, long-term prospective studies analyzing the effect of type 2 diabetes (T2D) on central arterial stiffness are lacking, and roles of fasting and postprandial blood glucose (FBG and PBG) in this effect are controversial. Purpose of the current analysis was to investigate the effect of T2D on central arterial stiffness during the 5 years of follow-up, and explore whether both FBG and PBG were determinants of this effect in Chinese community-dwelling population.

METHODS

The current analysis involved 898 individuals with carotid-femoral pulse wave velocity (cfPWV) ≤12 m/s. Central arterial stiffness was assessed by standard cfPWV at baseline and follow-up.

RESULTS

Incidence of cfPWV >12 m/s was 21.3% (102 participants). Participants without T2D had an increase of cfPWV with a median of 0.6 m/s, whereas participants with T2D had an increase of cfPWV with a median of 1.2 m/s (p = 0.007). T2D had an independent effect on increased cfPWV in multivariate Logistic regression models (p < 0.05 for all). Elevated levels of both FBG and PBG determined the independent effect on increased cfPWV in multivariate linear regression models (p < 0.05 for all).

CONCLUSIONS

Type 2 diabetes had an independent effect on the development of central arterial stiffness in Chinese community-dwelling population. Both FBG and PBG should be responsible for the development of central arterial stiffness and treated as the targets of glycemic control.

Glucose Exposure and Variability with Empagliflozin as Adjunct to Insulin in Patients with Type 1 Diabetes: Continuous Glucose Monitoring Data from a 4-Week, Randomized, Placebo-Controlled Trial (EASE-1)

BACKGROUND

We evaluated the effect of empagliflozin as adjunct to insulin on 24-h glucose exposure and variability in patients with type 1 diabetes.

METHODS

Patients (N = 75) with HbA_1c ≥7.5% to ≤10.5% were randomized to receive empagliflozin 2.5 mg, empagliflozin 10 mg, empagliflozin 25 mg, or placebo once daily as adjunct to insulin for 4 weeks. Insulin dose was to be kept as stable as possible during week 1 of treatment and was freely adjustable thereafter. Markers of glucose exposure and variability were assessed from 7-day blinded continuous glucose monitoring intervals. This study is completed ( ClinicalTrials.gov NCT01969747).

RESULTS

Empagliflozin reduced hourly mean glucose area under the median curve over 24 h versus placebo within week 1 (adjusted mean differences: -12.2 mg/dL·h [95% confidence interval -23.9 to -0.5], -30.2 mg/dL·h [-42.2 to -18.2], and -33.0 mg/dL·h [-44.8 to -21.1] with empagliflozin 2.5, 10, and 25 mg, respectively; all P < 0.05) and increased time in glucose target range (>70 to ≤180 mg/dL). Results were sustained to week 4 with empagliflozin 25 mg. All empagliflozin doses significantly reduced glucose variability (interquartile range and mean amplitude of glucose excursions) versus placebo at weeks 1 and 4. Except for small increases in hours per day with glucose ≤70 mg/dL during the stable insulin period, empagliflozin did not increase time in hypoglycemia compared with placebo.

CONCLUSIONS

In patients with type 1 diabetes, empagliflozin as adjunct to insulin decreased glucose exposure and variability and increased time in glucose target range.

Effect of serving size and addition of sugar on the glycemic response elicited by oatmeal: A randomized, cross-over study

BACKGROUND & AIMS

We aimed to determine the impact of serving size and addition of sucrose on the glycemic response elicited by oatmeal.

METHODS

We studied 38 healthy subjects (mean ± SD age 40 ± 12 yr, BMI 26.4 ± 3.6 kg/m²) on 8 separate days using a randomized, cross-over design. Capillary blood-glucose responses over 2hr after consuming 30, 40 and 60 g Classic Quaker Quick Oats (18, 24 and 36 g available-carbohydrate [avCHO], respectively) and 30 g Oats plus 9 g sucrose (27 g avCHO) were compared with those after avCHO-matched servings of Cream of Rice cereal (Control) (22, 29, 44 and 33 g cereal, respectively). Blood-glucose incremental area under the curve (iAUC), peak-rise, rate-of-decline, time-to-peak and time-to-baseline were calculated.

RESULTS

As serving size increased, iAUC, peak-rise, rate-of-decline and time-to-baseline increased significantly for both cereals, but the rate of increase was significantly greater for Control than for Oats. Time-to-peak increased significantly with serving size only for Oats. Compared to avCHO-matched servings of Control, mean (95%CI) iAUC, peak-rise and rate-of-decline, respectively were 22 (16, 27)%, 22 (19, 26)% and 23 (18, 27)% lower after consuming Oats without sucrose and 26 (18, 34)%, 14 (9, 20)% and 16 (9, 24)% lower after consuming Oats plus sucrose.

CONCLUSIONS

Oatmeal elicited a significantly lower glycemic response than avCHO-matched servings of Cream of Rice, even when sucrose was added to the oatmeal. Measures of glycemic response tended to increase with increased serving size; although the pattern of change varied between cereal types. These results suggest that oatmeal may be a good choice for minimizing postprandial glycemia.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov (NCT02506972).

Effect of a macronutrient preload on blood glucose level and pregnancy outcome in gestational diabetes

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Gestational diabetes (GDM) is associated with risks for both the mother and the child.

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A food composition, macro-nutrient preload, was given half an hour before each meal.

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Thirty-three GDM patients were given macro-nutrient preload and 33 a control comparator.

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A two-month macro-nutrient preload treatment of GDM improved post-prandial glycemia.

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Macro-nutrient preload treatment is of a potential value for future management of GDM.

Aim

To investigate the effect of a macro-nutrient preload (Inzone Vitality) on blood glucose levels and pregnancy outcomes of gestational diabetes. The preload method involves the ingestion of a smaller amount of a macronutrient composition half an hour before regular meals. The hypothesis was that preload treatment will reduce postprandial glycemia in gestational diabetes.

Methods

Sixty-six diagnosed cases of gestational diabetes were randomly selected from gynecology and obstetrics outpatient clinic at Xinqiao Hospital in Chongqing. The patients were divided into an intervention group (33 cases) and a control group (33 cases), according to odd–even numbers of the random cases. The intervention group was treated with a macro-nutrient preload given 0.5 h before regular meals and the control group was given a comparative treatment consisting of a milk powder with similar energy content. The two groups were studied until delivery and the measured parameters included fasting blood glucose (FBG), 2-hour postprandial blood glucose (2h-PBG), delivery mode and neonatal birth weight.

Results

The two groups showed no differences in FBG or 2h-PBG before the nutritional intervention. FBG and 2h-PBG after intervention and before delivery were significantly lower in the intervention group, treated with the macro nutrient preload compared to the control group (P < 0.01). Changes in FBG and 2h-PBG before and after the intervention were investigated and the difference in the intervention group was significantly greater than corresponding values in the control group (P < 0.05, P < 0.01). The neonatal birth weight and delivery mode was not significantly different (P > 0.05).

Conclusion

A macro-nutrient composition, used as a preload, is effective in controlling FBG and PBG of gestational diabetes.

Glycemic load, exercise, and monitoring blood glucose (GEM): A paradigm shift in the treatment of type 2 diabetes mellitus

AIMS

This preliminary RCT investigated whether an integrated lifestyle modification program that focuses on reducing postprandial blood glucose through replacing high with low glycemic load foods and increasing routine physical activities guided by systematic self-monitoring of blood glucose (GEM) could improve metabolic control of adults with type 2 diabetes mellitus, without compromising other physiological parameters.

METHODS

Forty-seven adults (mean age 55.3 years) who were diagnosed with type 2 diabetes mellitus for less than 5 years (mean 2.1 years), had HbA1c ≥ 7% (mean 8.4%) and were not taking blood glucose lowering medications, were randomized to routine care or five 1-h instructional sessions of GEM. Assessments at baseline and 6 months included a physical exam, metabolic and lipid panels, and psychological questionnaires.

RESULTS

The GEM intervention led to significant improvements in HbA1c (decreasing from 8.4 to 7.4% [69-57 mmol/mol] compared with 8.3 to 8.3% [68-68 mmol/mol] for routine care; Interaction p<.01) and psychological functioning without compromising other physiological parameters.

CONCLUSIONS

Consistent with a patient-centered approach, GEM appears to be an effective lifestyle modification option for adults recently diagnosed with type 2 diabetes mellitus.

Effects of Korean White Ginseng (Panax Ginseng C.A. Meyer) on Vascular and Glycemic Health in Type 2 Diabetes: Results of a Randomized, Double Blind, Placebo-controlled, Multiple-crossover, Acute Dose Escalation Trial

Korean red ginseng (steam treated Panax ginseng C.A. Meyer), among most prized traditional herbal remedies, has been clinically shown to improve cardiovascular disease (CVD) risk factors. Whether this holds true for the dried non-steamed variety, known as Korean white ginseng (KWG) is unclear. This study therefore, investigated the efficacy and safety of escalating doses of KWG on vascular and glycemic parameters in type 2 diabetes (T2DM). Using an acute, randomized, placebo-controlled, double-blind, crossover design, 25 participants with well-controlled T2DM (12-males: 13-females, age: 63 ± 9 years, A1c: 6.9 ± 0.7%, BMI: 29.3 ± 4.3 kg/m²) underwent five visits during which they received 1 g, 3 g, or 6 g KWG or 3 g wheat-bran control (twice) together with 50 g-glucose load. For the duration of 240 minutes, augmentation index (AI), and central blood pressure were measured at baseline and at 60 min-intervals, and ambulatory blood pressure was assessed at baseline and at 10 min-intervals. Additionally, capillary blood was collected at time zero and at 15, 30, 45, 60, 90, 120, and 180 minutes post-treatment. A symptoms questionnaire was used to assess safety and adverse events. Two-way ANOVA demonstrated a significant time-treatment interaction effect on AI (p = 0.01) with one-way ANOVA showing significant reductions in AI with 3 g KWG relative to control (p = 0.04). Compared to control, acute administration of KWG appeared to be safe, but did not affect any other postprandial, vascular or glycemic parameters. KWG might have a beneficial effect on AI, a cumulative indicator of arterial health. However, these results are preliminary and highlight the need for long-term investigation with a focus on its accountable components. Clinical Trial Registration: NCT01699074

Synergistic postprandial blood glucose modulatory properties of Vernonia amygdalina (Del.), Gongronema latifolium (Benth.) and Occimum gratissimum (Linn.) aqueous decoctions

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional healers in Nigeria use a combination of decoctions from green leafy vegetables in their blood glucose (BG) lowering recipes. Three plants Vernonia amygdalina (Del.) (VA), Gongronema latifolium (Benth.) (GL) and Occimum gratissimum (Linn.) (OG) are found consistently in such recipes. Whereas the anti-diabetic properties of extracts of these plants have been reported in animal models, little is known about the effects of their aqueous decoctions (singly or in combinations) on oral glucose tolerance (OGT) in humans.

MATERIALS AND METHODS

Twenty seven subjects were recruited and (on separate days) were given 150 mL of water, VA, GL and OG decoctions or blends of the decoctions to drink 45 min before a 2-h OGTT. Their OGTT curves were plotted and areas under the curves (AUCs) calculated.

RESULTS

The results show that each of the three decoctions neither altered the peak time of the OGTT nor significantly (P>0.05) reduced the BG concentrations (BGCs) at any time point on the test curves relative to the baseline. VA, OG and GL gave 0.4, 0.2 and 2.8% reductions in the AUCs, respectively, relative to the baseline. Blending GL and VA did not improve the results. However, a decoction containing the three vegetables in equal proportions significantly reduced the BGCs at 90 (96.8 ± 9.5 vs. 107.1 ± 10.2mg/dL; P=0.041) and 120 (92.8 ± 14.3 vs. 102.5 ± 12.1mg/dL; P=0.037) minutes relative to the baseline, and gave better reductions in the AUCs (4.1%).

CONCLUSION

The decoction containing the three vegetables was found to be superior in activity to any 1, or blends of only 2, of the 3 decoctions. This is a case of positive synergism, and justifies the use of these plants in ethnopharmacological BG lowering recipes.

Gongronema latifolium delays gastric emptying of semi-solid meals in diabetic dogs

The aim of the study was to investigate sonographically the effect of Gongronema latifolium on gastric emptying of semi-solid meals in diabetic dogs. Twenty-five alloxan-induced diabetic dogs were randomly allotted into five groups of five dogs each in a randomised placebo-controlled study. These are placebo, prokinetic dose, low dose, moderate dose and high dose groups. The placebo group served as the control. The low, moderate and high dose groups ingested methanolic leaf extract of G. latifolium at 100 mg/kg, 250 mg/kg, 500 mg/kg respectively, while the prokinetic group ingested 0.5 mg/kg of metoclopramide. After a 12-hour fast, each group ingested its treatment capsules 30 minutes before the administration of test meal. Measurements of gastric emptying and blood glucose levels were obtained from each dog 30 minutes before and immediately after the ingestion of a test meal, every 15 minutes for another 4 hours and then every 30 minutes for further 2 hours. Gastric emptying of the moderate and high dose groups were 227.8 ± 9.9 min and 261.3 ± 19.3 min respectively and significantly (p < 0.0001) slower than the placebo control group of 143.0 ± 17.8 min. The gastric emptying of the low dose group (169.8 ± 3.8) and control group did not differ significantly (p > 0.05). A strong inverse relationship between gastric emptying and the incremental blood glucose levels was noted in the diabetic dogs after the ingestion of Gongronema latifolium (r = -0.90; p < 0.0001). Gonogronema latifolium delayed gastric emptying in diabetic dogs.

Effects of lixisenatide once daily on gastric emptying in type 2 diabetes--relationship to postprandial glycemia

OBJECTIVES

To determine the effects of lixisenatide, a new once-daily (QD) glucagon-like peptide-1 receptor agonist, on postprandial glucose (PPG) and gastric emptying, and the relationship between these effects in patients with type 2 diabetes mellitus (T2DM).

METHODS

Data were obtained from a randomized, double-blind, placebo-controlled, parallel-group study with treatment duration of 28 days in patients with T2DM receiving ≤2 oral antidiabetic drugs. Lixisenatide was injected subcutaneously using an ascending dose range (5-20 μg) increased every fifth day in increments of 2.5 μg. Blood glucose was determined before and after three standardized meals (breakfast, lunch, and dinner). Gastric emptying of the standardized breakfast was determined by a (13)C-octanoic acid breath test at baseline (Day-1) and at Day 28.

RESULTS

A total of 21 and 22 patients were randomized to lixisenatide 20 μg QD and placebo, respectively. With lixisenatide 20 μg QD, there was a reduction in PPG when compared with placebo after breakfast (p<0.0001), lunch (p<0.001) and dinner (p<0.05). Hence, lixisenatide 20 μg administered in the morning exhibited a pharmacodynamic effect on blood glucose throughout the day. Gastric emptying (50% emptying time) increased substantially from baseline with lixisenatide 20 μg QD, but not with placebo (change from baseline ± SD: -24.1 ± 133.1 min for placebo and 211.5 ± 278.5 min for lixisenatide; p<0.01). There was an inverse relationship between PPG area under the curve after breakfast and gastric emptying with lixisenatide 20 μg QD (n=17, r(2)=0.51, p<0.05), but not with placebo.

CONCLUSIONS

In this study, lixisenatide at a dose of 20 μg QD reduced postprandial glycemic excursions in patients with T2DM, possibly as a result of sustained slowing of gastric emptying.

Effect of Gongronema latifolium on gastric emptying in healthy dogs

AIM: To investigate sonographically the effect of Gonogronema latifolium (G. latifolium) on gastric emptying of semi-solid meals in healthy dogs.

METHODS: In a randomized, placebo-controlled experiment, twenty-five clinically healthy dogs were randomly allotted into five groups of five dogs in each group. The placebo group served as the control, and the low, moderate and high dose groups ingested the methanolic leaf extract of G. latifolium in capsules at 100 mg/kg, 250 mg/kg and 500 mg/kg, respectively, while the prokinetic group ingested 0.5 mg/kg capsules of metoclopramide. After a 12-h fast, each group ingested its treatment capsules 30 min before the administration of a test meal. Measurements of gastric emptying and blood glucose levels were obtained 30 min before and immediately after the ingestion of the test meal and thereafter every 15 min for 4 h. This was followed by further measurements every 30 min for another 2 h.

RESULTS: The gastric emptying times of the placebo, low dose, moderate dose, high dose and prokinetic dose groups were 127.0 ± 8.2 min, 135.5 ± 3.7 min, 155.5 ± 3.9 min, 198.0 ± 5.3 min and 59.0 ± 2.5 min, respectively. Gastric emptying times of the moderate and high dose groups were significantly slower than in the placebo control group (155.5 ± 3.9 min, 198.0 ± 5.3 min vs 127.0 ± 8.2 min, P = 0.000). No significant difference in gastric emptying between the low dose and placebo control groups was noted (135.5 ± 3.7 min vs 127.0 ± 8.2 min, P = 0.072). Gastric emptying of the prokinetic group was significantly faster than that of the control group (59.0 ± 2.5 min vs 127.0 ± 8.2 min, P = 0.000). The hypoglycaemic effect of G. latifolium and gastric emptying were inversely related (r = -0.95, P = 0.000).

CONCLUSION: G. latifolium delays gastric emptying and lowers postprandial blood glucose in healthy dogs. It reduces the postprandial blood glucose by delaying gastric emptying.