Postprandial Blood Glucose Concentrations Research Articles

Two weeks of acarbose treatment shows no effect on gut microbiome composition in patients with type 2 diabetes: a randomised, placebo-controlled, double-blind, crossover study.

The alpha-glucosidase inhibitor acarbose is approved for the treatment of type 2 diabetes (T2D). It acts in the lumen of the gut by reducing intestinal hydrolysis and absorption of ingested carbohydrates. This reduces postprandial blood glucose concentration and increases the content of carbohydrates in the distal parts of the intestine potentially influencing gut microbiome (GM) composition and possibly impacting the gut microbiome (GM) dysbiosis associated with T2D. Here, we investigated the effect of acarbose on GM composition in patients with T2D. Faecal samples were collected in a previously conducted randomised, placebo-controlled, double-blind, crossover study in which 15 individuals with metformin-treated T2D (age 57-85 years, HbA1c 40-74 mmol/mol, BMI 23.6-34.6 kg/m2) were subjected to two 14-day treatment periods with acarbose and placebo, respectively, separated by a 6-week wash-out period. Faecal samples were collected before and by the end of each treatment period. The GM profiles were evaluated by 16S rRNA gene amplicon sequencing. The GM profiles after the treatment periods with acarbose or placebo remained unaffected (P > 0.7) when compared with the GM profiles before treatment. This applied to the analysis of within-sample diversity (α-diversity) and between-sample bacterial composition diversity (β-diversity). Additionally, no dominant bacterial species differentiated the treatment groups, and only minor increases in the relative abundances of Klebsiella spp. and Escherichia coli (P < 0.05) were observed after acarbose treatment. In patients with metformin-treated T2D, 14 days of treatment with acarbose showed only minor effects on GM as seen in increased relative abundances of Klebsiella spp. and Escherichia coli.

Study on the effectiveness of postprandial blood glucose control and glycemic index of acetylated wheat flour in healthy volunteers

Background: The study was conducted to determine the ability to control postprandial blood glucose response and glycemic index of acetylated wheat starch cakes containing 31,2% of resistant starch on 12 healthy volunteers. Material and methods: Research designed using experimental and double-blind methods. During the two days of the clinical trial, after more than 12 hours of overnight fasting, each volunteer consumed a diet consisting of 1 cake containing 50 g of acetylated wheat starch or 50 g of natural wheat starch and 330 ml of filtered water in 15 minutes. Volunteers had determined their capillary blood glucose concentrations at times before meals, 60 and 120 minutes after meals. Results: Blood glucose concentration at 60 minutes after eating acetylated wheat starch cake (G1= 8.6 ± 0.8 mmol/L) was lower than natural wheat starch cake (G1= 11.7 + 1.1 mmol/L) (p &lt; 0.05). Similarly, blood glucose concentration at 120 minutes after eating acetylated wheat starch cake (G2= 7.1 ± 0.7 mmol/L) was lower than natural wheat starch cake (G2= 9.2 ± 1.7 mmol/L) (p &lt; 0.05). The area under the curve of blood glucose concentration after 120 minutes of eating natural wheat starch cake (AUC0-120min= 337.0 min*mmol/L) is doulble times larger than the acetylated wheat starch cake (AUC0-120min= 175.5 min*mmol/L) (p &lt; 0.05). Glycemic index of acetylated wheat starch cake is 52.0. Conclusion: Acetylated wheat starch cake has a low glycemic index, possessing the ability to control postprandial blood glucose effectively, limiting the increase of postprandial blood glucose concentration within the safe range, and it did not cause any digestive disorders in volunteers. This is very meaningful in the application of acetylated wheat starch to process foods not only for diabetic patients but also for pre-diabetic or overweight and obese people to support treatment and improve quality of life. Key words: resistant starch, blood glucose, glycemic index, volunteers.

Glycemic and Satiety Response to Three Mexican Honey Varieties.

Honey is considered one of the last untreated natural food substances, with a complex composition. It is produced by bees (Apis mellifera) from nectar. The glycemic index (GI) is a physiological assessment of a food's carbohydrate content via its effect on postprandial blood glucose concentrations. This study evaluated the GI and the satiety response to three Mexican types of honey administered to 26 healthy volunteers. The fructose values ranged from 272.40 g/kg to 395.10 g/kg, while the glucose value ranged from 232.20 g/kg to 355.50 g/kg. The fructose/glucose (F/G) ratio of honey was 1.45, 1.00, and 1.17 for highland, multifloral, and avocado honey, respectively. Highland and avocado honey were classified as medium-GI (69.20 ± 4.07 and 66.36 ± 5.74, respectively), while multifloral honey was classified as high-GI (74.24 ± 5.98). Highland honey presented a higher satiety values response than glucose. The difference in GI values and the satiety response effect of highland honey could be explained by its different carbohydrate composition and the possible presence of other honey components such as phytochemicals. Honey, especially avocado, could therefore be used as a sweetener without altering significantly the blood glucose concentration.

Whey Protein Premeal Lowers Postprandial Glucose Concentrations in Adults Compared with Water—The Effect of Timing, Dose, and Metabolic Status: a Systematic Review and Meta-analysis

BackgroundServing whey protein before a meal in order to lower postprandial blood glucose concentrations is known as a premeal. The underlying mechanisms are only partly understood but may involve stimulation of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and insulin secretion together with a slower gastric emptying rate. ObjectivesThe objective of this systematic review and meta-analysis was to review all randomized clinical trials investigating premeals with whey protein in comparison with a nonactive comparator (control) that evaluated plasma glucose, GLP-1, GIP, insulin, and/or gastric emptying rate. Secondary aims included subgroup analyses on the timing and dose of the premeal together with the metabolic state of the participants [lean, obese, and type 2 diabetes mellitus (T2DM)]. MethodsWe searched EMBASE, CENTRAL, PUBMED, and clinicaltrials.gov and found 16 randomized crossover trials with a total of 244 individuals. The last search was performed on 9 August, 2022. ResultsWhey protein premeals lowered peak glucose concentration by −1.4 mmol/L [−1.9 mmol/L; −0.9 mmol/L], and the area under the curve for glucose was −0.9 standard deviation (SD) [−1.2 SD; −0.6 SD] compared with controls (high certainty). In association with these findings, whey protein premeals elevated GLP-1 (low certainty) and peak insulin (high certainty) concentrations and slowed gastric emptying rate (high certainty) compared with controls. Subgroup analyses showed a more pronounced and prolonged glucose-lowering effect in individuals with T2DM compared with participants without T2DM. The available evidence did not elucidate the role of GIP. The protein dose used varied between 4 and 55 g, and meta-regression analysis showed that the protein dose correlated with the glucose-lowering effects. ConclusionsIn conclusion, whey protein premeals lower postprandial blood glucose, reduce gastric emptying rate, and increase peak insulin. In addition, whey protein premeals may elevate plasma concentrations of GLP-1. Whey protein premeals may possess clinical potential, but the long-term effects await future clinical trials.

235-LB: Incretin-Linked Adipose Tissue Microvascular Blood Flow in Healthy People With and Without a Family History of Type 2 Diabetes

Adipose tissue microvascular blood flow (ATMBF) increases in response to a mixed meal challenge (MMC) to promote nutrient storage. This vascular action is impaired in apparently healthy people with a parent with type 2 diabetes (FH+). The mechanisms for this vascular impairment in FH+ are unknow. We aimed to investigate whether incretins [glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1)] are associated with ATMBF responses to a MMC. Thirteen healthy (FH-, no parents or grandparents with type 2 diabetes) and fourteen FH+ underwent a 2-hr MMC after an overnight fast. Age, BMI, fasting and peak postprandial blood glucose and plasma insulin concentrations were similar between FH- and FH+ (Table 1). Baseline ATMBF, assessed by contrast ultrasound, was similar between groups, but was impaired in FH+ in response to the MMC (Table 1). Peak plasma GLP-1 and GIP concentrations, but not their ratio (GLP-1:GIP), were higher in FH+ in response to the MMC (Table 1). GLP-1 and GIP concentrations were not associated with ATMBF, however, GLP-1:GIP was significantly associated with postprandial ATMBF at 1-hr (p=0.025, r=0.46). We conclude that impaired postprandial ATMBF in FH+ is not exclusively linked to incretin levels. However, lower GLP-1:GIP ratios may be linked to impaired ATMBF responses in the postprandial state. Disclosure K. Roberts-thomson: None. L. Parker: None. M. Keske: None.

The effect of mycoprotein intake on biomarkers of human health: a systematic review and meta-analysis

BackgroundMycoprotein is a fungal source of protein that is increasingly consumed as an ingredient in meat analogs. ObjectivesThis study aimed to systematically review and meta-analyze the effects of mycoprotein intake on selected biomarkers of human health. MethodsThis study was registered in PROSPERO (CRD42022308980). We searched the PubMed, Scopus, and Embase databases to identify randomized control trials in any language until 16 August, 2022. Trials were included if they administered a mycoprotein intervention against a nonmycoprotein control arm and if reported outcomes included blood lipids, blood glucose, insulin, blood pressure, or body weight. Eligible trials were assessed for risk of bias using the Cochrane risk-of-bias tool for randomized trials. An inverse-variance–weighted, random-effects meta-analysis model was used to assess the effects of intake across each biomarker. ResultsNine trials that included 178 participants with a mean follow-up of 13 d were included, with 4 reporting on blood lipids and 5 reporting on postprandial blood glucose or insulin. The overall reduction of total cholesterol was −0.55 mmol/L (95% CI: −0.85 to −0.26; P < 0.001) in the mycoprotein group compared to control, but no clear effects on HDL cholesterol, LDL cholesterol, or TGs were found (all P > 0.05). There were no reductions in postprandial blood glucose concentrations at 30, 60, 90 or 120 min. Postprandial blood insulin concentration was reduced by −76.51 pmol/L (95% CI: −150.75 to −2.28; P = 0.043) at 30 min, with no detectable effects at 60, 90, or 120 min. ConclusionsMycoprotein intake may have important effects on blood lipids, but the evidence base is limited by the small sample sizes and short intervention periods of the contributing trials.The protocol for this systematic review has been registered in PROSPERO as CRD42022308980.

Allulose for the attenuation of postprandial blood glucose levels in healthy humans: A systematic review and meta-analysis.

D-Allulose is a rare sugar that exists in nature. It is a food ingredient with nearly zero calories (<0.4 kcal/g) and has many physiological functionalities such as attenuation of postprandial blood glucose levels, attenuation of postprandial fat mass accumulation, and anti-aging property. This study focused on the postprandial blood glucose changes in healthy humans by a systematic review and meta-analysis. They were chosen because of its importance to a prevention from diabetes. The study objective was to examine acute blood glucose concentrations of healthy humans after the meal with and without allulose. The study collected all D-allulose related studies from various databases. A forest plot of the comparison between an allulose intake group and the control group showed both 5g and 10g intake groups have the significantly smaller area under the curve of postprandial blood glucose levels. It means that D-Allulose attenuates postprandial blood glucose concentrations in healthy humans. As the result, D-Allulose is a valuable blood glucose management tool for healthy humans and diabetes patients. Allulose Diet enables reduction of sucrose intake through Sugar Reformulation in the future diet.

A “PAKU-PAKU KOUBO-KUN” containing yeast and mulberry extract postprandial glycemic control in healthy Japanese men and women: a randomized, placebo-controlled, crossover study

Objective: This study’s purpose was to verify the PAKU-PAKU KOUBO-KUN (PPKK) containing yeast and mulberry extract concentrate’s effects on suppressing elevated postprandial blood glucose (PBG).Methods: Two randomized, placebo-controlled, crossover studies (TRIAL-1 and TRIAL-2) were conducted. Both studies included healthy Japanese adults with a maximum PBG concentration (Cmax) in the range of 140–199 mg/dL. Study subjects were randomly assigned to take PPKK or placebo food. Then subjects consumed 200 g of cooked rice within 10 minutes of test food consumption. Blood glucose (BG) levels were evaluated before intervention, and 30 min, 60 min, 90 min, and 120 min after consumption. The main endpoint was the incremental area under the curve (IAUC) of PBG.Results: The analysis included 36 subjects in TRIAL-1 and 41 subjects in TRIAL-2. A combined analysis (n = 71) was conducted. Both individual studies and combined analysis showed that PPKK significantly reduced the IAUC of PBG. In particular, BG levels were significantly lower at 30 min, 60 min, and 90 min after intervention. No adverse effects were identified. Conclusions:These results indicated that PPKK moderated the increase in PBG and enhanced glucose metabolism.Trial registration: UMIN-CTR: UMIN000042445 and UMIN000045341Foundation: Mainichiegao Co., Ltd.Keywords: postprandial blood glucose, yeast, mulberry, prediabetes, glycemic control

Effects of a genetic variant rs13266634 in the zinc transporter 8 gene (SLC30A8) on insulin and lipid levels before and after a high-fat mixed macronutrient tolerance test in U.S. adults

BackgroundThe common C-allele of rs13266634 (c.973C>T or p.Arg325Trp) in SLC30A8 (ZNT8) is associated with increased risk of type 2 diabetes. While previous studies have examined the correlation of the variant with insulin and glucose metabolism, the effects of this variant on insulin and lipid responses after a lipid challenge in humans remain elusive. The goal of this study was to determine whether the C-allele had an impact on an individual’s risk to metabolic syndromes in U.S. adults. MethodWe studied the genotypes of rs13266634 in 349 individuals aged between 18 and 65 y with BMI ranging from 18.5 to 45 kg/m2. The subjects were evaluated for insulin, glucose, HbA1c, ghrelin, and lipid profiles before and after a high-fat mixed macronutrient tolerance test (MMTT). ResultsWe found that the effects of variants rs13266634 on glucose and lipid metabolism were sex-dimorphic, greater impact on males than on females. Insulin incremental area under the curve (AUC) after MMTT was significantly decreased in men with the CC genotype (p < 0.05). Men with the CC genotype also had the lowest fasting non-esterified fatty acid (NEFA) concentrations. On the other hand, the TT genotype was associated with a slower triglyceride removal from the circulation in men after MMTT. The reduced triglyceride removal was also observed in subjects with BMI ≥ 30 carrying either the heterozygous or homozygous T-allele. Nevertheless, the SNP had little effect on fasting or postprandial blood glucose and cholesterol concentrations. ConclusionWe conclude that the CC genotype negatively affects insulin response after MMTT while the T-allele may negatively influence lipolysis during fasting and postprandial blood triglyceride removal in men and obese subjects, a novel finding in this study.

Elevations in blood glucose before and after the appearance of islet autoantibodies in children.

The etiology of type 1 diabetes has polygenic and environmental determinants that lead to autoimmune responses against pancreatic β cells and promote β cell death. The autoimmunity is considered silent without metabolic consequences until late preclinical stages,and it remains unknown how early in the disease process the pancreatic β cell is compromised. To address this, we investigated preprandial nonfasting and postprandial blood glucose concentrations and islet autoantibody development in 1,050 children with high genetic risk of type 1 diabetes. Pre- and postprandial blood glucose decreased between 4 and 18 months of age and gradually increased until the final measurements at 3.6 years of age. Determinants of blood glucose trajectories in the first year of life included sex, body mass index, glucose-related genetic risk scores, and the type 1 diabetes–susceptible INS gene. Children who developed islet autoantibodies had early elevations in blood glucose concentrations. A sharp and sustained rise in postprandial blood glucose was observed at around 2 months prior to autoantibody seroconversion, with further increases in postprandial and, subsequently, preprandial values after seroconversion. These findings show heterogeneity in blood glucose control in infancy and early childhood and suggest that islet autoimmunity is concurrent or subsequent to insults on the pancreatic islets.

Oral Glucose-Responsive Nanocarrier System for Management of Diabetes

Background: The regulation of postprandial blood glucose concentration in a diabetic person is a toilsome task by the conventional approaches. The continuous monitoring and subcutaneous injection of insulin are always imperative for diabetes management. To overcome the hurdle associated with the conventional system, a glucose-responsive nanoparticle (NP)-based approach was developed for oral insulin administration. The objective of the work is the formulation and characterization of a nanocarrier-based bio-responsive, self-regulated oral insulin drug delivery system. Methods: The mannose ligand-conjugated NPs were prepared by the inotropic gelation method in which insulin and glucose oxidase enclosed alginate nanocarrier cross-linked by tripolyphosphate. The prepared NPs were filled into the enteric-coated capsule and their release profile was determined at different pH and glucose concentrations. NPs were characterized by size distribution, % drug entrapment, enzyme activity, and in vivo and in vitro drug release studies. Results: The average size, surface potential, % drug entrapment of optimized NPs were 245.52 ± 3.37 nm, 22.12 ± 2.13, and 76.15±1.3%, respectively. The release of insulin from optimized NPs (GOx-ALG-MCNPs) (98.56±0.06%) occurs only at higher sugar concentrations (? 400 mg/dL) and prevents the release at low sugar concentrations (&lt; 100 mg/dL). The enteric capsule shell protected the formulation to the gastric environment upon oral administration and directed them into the intestine. Mucoadhesion characteristics of NPs prolonged intestinal retention to make them available for cellular uptake. Glucose sensitivity and glucose-dependent effect on different pH environments study revealed that NPs released the drug only at higher concentrations of sugar solution while inhibiting the release at normal and lower sugar concentrations. Besides, compared to other prepared formulations, the GOx-ALG-MCNPs displayed controlled insulin release in response to glucose concentration. Conclusions: An important finding of GOx-ALG-MCNPs is auto-regulating, glucose-responsive behavior imparting a significantly controlled lowering of blood glucose in an animal model. The findings reveal that the developed glucose-responsive NPs may prove to be a potential strategy for oral insulin delivery. J Endocrinol Metab. 2022;12(4-5):146-160 doi: https://doi.org/10.14740/jem747

251 A Combination of Dietary Isoleucine and Valine Above Recommended Levels Improves the Growth and Alters the Metabolites Profile in Pigs fed with Very low Protein Diets

Abstract Very low-protein (VLP) diets are beneficial for reducing the nitrogen excretion from swine production, but these diets depress the performance of pigs while supplemented with first four limiting amino acids (FFL; i.e. Lys, Met, Thr and Trp). The objective of this study was to investigate the effect of supplementation of Val and Ile above NRC (2012) levels on performance, thermal radiation and blood metabolites of pigs fed with VLP diets. Three-week-old weaned barrows (n = 40) were assigned to: positive control (PC): normal protein diet; negative control (NC): VLP diet containing FFL at NRC levels; HV: NC with Val above NRC; HI: NC with Ile above NRC; HVI: NC with both Val and Ile above NRC. After 5 weeks of data collection, blood samples were collected. Univariate GLM with Tukey post-hoc test was used to analyze the data (SPSS). Pigs fed with NC had a decreased average daily gain (ADG) and average daily feed intake (ADFI) compared with PC (P&amp;lt; 0.05). HVI pigs had less ADG than PC, but greater ADG than NC (P&amp;lt; 0.05). ADFI of pigs fed with HVI was similar to PC and it was greater than NC (P&amp;lt; 0.05). HVI pigs had a higher thermal radiation than NC (P&amp;lt; 0.05). While HVI pigs had greater blood glucose than PC and NC at baseline (P&amp;lt; 0.05), no differences among these groups were observed on postprandial blood glucose concentration. HVI pigs had less blood triglycerides than PC. All groups increased the blood cholesterol compared with PC (P&amp;lt; 0.05). There were no differences in blood urea nitrogen (BUN) for NC vs. PC; however, pigs fed with HVI reduced the BUN compared with NC (P&amp;lt; 0.05). In conclusion, supplementation of Val and Ile greater than NRC into VLP diets partially restored the performance and fully recovered the ADFI, reduced the blood triglycerides and BUN, and improved the glucose tolerance.

Identification of a novel α-glucosidase inhibitor from Melastoma dodecandrum Lour. 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.

5 days of time-restricted feeding increases fat oxidation rate but not affect postprandial lipemia: a crossover trial

Studies have revealed that time-restricted feeding affects the fat oxidation rate; however, its effects on the fat oxidation rate and hyperlipidemia following high-fat meals are unclear. This study investigated the effects of 5-day time-restricted feeding on the fat oxidation rate and postprandial lipemia following high fat meals. In this random crossover experimental study, eight healthy male adults were included each in the 5-day time-restricted feeding trial and the control trial. The meals of the time-restricted feeding trial were provided at 12:00, 16:00, and 20:00. The meals of the control trial were provided at 08:00, 14:00, and 20:00. The contents of the meals of both trials were the same, and the calories of the meals met the 24-h energy requirement of the participants. After 5 days of the intervention, the participants consumed high-fat meals on the sixth day, and their physiological changes were determined. The fasting fat oxidation rate (p < 0.001) and postprandial fat oxidation rate (p = 0.019) of the time-restricted feeding trial were significantly higher than those of the control trial. The 24-h energy consumption and postprandial triglyceride, blood glucose, insulin, glycerol, and free fatty acid concentrations of the two trials showed no significant differences (p > 0.05). The results revealed that 5 days of time-restricted feeding effectively increased the fasting and postprandial fat oxidation rate, but it did not affect postprandial lipemia.

Age-associated weight gain as potential risk of hyperglycemic indications in randomised middle-aged and geriatric population of Darbhanga, Bihar, India

The present study was undertaken with a view to investigate suitability of age-associated weight gain as potential risk of hyperglycemic indications in randomised middle-aged and geriatric population of Darbhanga, Bihar. Quantitative estimations of Fasting and 2 hours Post-Prandial Blood Glucose concentrations in both the sexes of urbanite human subjects (n=460)residing in Darbhanga, a commissionary town of Bihar, India and consented for required clinical tests were carried out. The study population was categorised into two age intervals of 45-59 and 60-75 years and two BMI-linked obesity groups comprised of Normal Weight and Overweight/Obese individuals. Results showed a trend of marked elevation in observed mean values of chosen blood parameters in subjects from Over weight/ Obese groups as compared to those from Normal Weight groups in both the age intervals and appeared suggestive of occurrence of hyperglycemic alterations with accompanying glucose intolerance. Findings seemingly affirm age-associated weight gain as potential risk of hyperglycemic perturbations in randomised middle-aged and geriatric population of urban Darbhanga.

Adverse effect of switching only once low-carbohydrate diet to high-carbohydrate diet on postprandial glucose concentration in healthy women.

Our aim was to evaluate the acute effect of switching low-carbohydrate diet (LCD) to high-carbohydrate diet (HCD) on glycemic parameters in healthy women. Twen-ty-two women (age 21.7±4.0 years; HbA1c 5.3±0.3 %, mean±SD) wore flash glucose monitoring system and consumed test meals for 3 days from Day 4 to 6. Participants consumed identical HCD meals except LCD dinner on Day 5. The energy ratio of carbohydrate, fat, and protein were 64%, 21%, and 15% for HCD and 47%, 35%, and 18% for Day 5 with LCD dinner (19%, 59%, and 22%). The incremental glucose peak (IGP, both p<0.001) and incremental area under the curve for glucose (IAUC, both p<0.001) 3h of LCD dinner were all sig-nificantly lower than those of HCD dinner on Day 4 and 6. However, after consuming LCD dinner on Day 5, IGP breakfast (2.33±0.15 vs 1.71±0.15 mmo/L, p<0.01), IGP lunch (3.31±0.25 vs 2.54±0.18 mol/L, p<0.01), IAUC 3h of breakfast (210±18 vs 136±14 mmol/L×min, p<0.001), mean blood glucose (5.72±0.11 vs 5.40±0.11 mmol/L, p<0.01), and standard deviation (1.11±0.06 vs 0.88±0.04 mmol/L, p<0.01) on Day 6 were all signifi-cantly higher than those of corresponding meals before LCD dinner on Day 4, in spite of consuming all identical HCD meals. The glycemic parameters returned to the levels before consuming LCD on Day 7. Consuming LCD only once is enough to cause 24-h higher postprandial blood glucose concentration in subse-quent consumption of HCD in healthy women.

An algorithm mimicking pancreas pulsatile behavior improves artificial pancreas performance.

Artificial pancreas design using subcutaneous insulin infusion without pre-meal feed-forward boluses often induces an over-response leading to hypoglycemia due to the increase of blood insulin concentration sustained in time. The objective of this work was to create an algorithm for controlling the function of insulin pumps in closed-loop systems to improve blood glucose management in type 1 diabetic patients by mimicking the pulsatile behaviour of the pancreas. A controller tuned in a pulsatile way promotes damped oscillations of blood insulin concentration injected through an insulin pump. We tested it in a simulated environment, using nine 'in silica' subjects. The control algorithm is founded on feedback linearization where through a change of variables, the nonlinear system turns into an equivalent linear system, suitable for implementing through a PID controller. We compared the results obtained 'in silica' with the volume injected by an insulin pump controlled by this algorithm. The use of this algorithm resulted in a pulsatile control of postprandial blood glucose concentration, avoiding hypoglycaemic episodes. The results obtained 'in silica' were replicated in a real pump 'in vitro'. With this proposed linear system, an appropriate control input can be designed. The controller works with a damped pulsatile pattern making the insulin infusion from the pump and blood insulin concentration pulsatile. This operational would improve the performance of an artificial pancreas.

203-LB: Boosted Beta-Cell Function with Selective Deletion of the Adaptor Protein Mig6

Type 1 and type 2 diabetes (T1D and T2D) are characterized by absolute and relative insulin deficiency, respectively. Thus, fortifying functional beta cell mass is essential for preventing or reversing either form of diabetes. We have investigated the impact of the adaptor protein mitogen inducible gene 6 (Mig6), a feedback inhibitor of epidermal growth factor receptor (EGFR) signaling induced in the diabetic milieu, on functional beta cell mass in the context of T1D and T2D. Given the importance of EGFR signaling in establishing and maintaining functional beta cell mass, we hypothesized that a selective loss of Mig6 in beta cells would increase functional beta cell mass. To this end, we generated mice lacking Mig6 in beta cells (BKO) using Mig6 floxed and Ins1-Cre knock-in mice and conducted extensive phenotyping, including quantifying beta cell function in vivo with hyperglycemic clamps. Compared to control littermates (CON), BKO mice had comparable beta cell mass, glucose tolerance, and post-prandial blood glucose or insulin concentrations when fed a standard chow diet. Mice underwent surgical catheterization of a carotid artery and jugular vein, and were allowed to recover for 4 days. Following a 5-h fast, mice were administered a primed and subsequent variable glucose infusion designed to clamp blood glucose at 15 mM (270 mg/dl). Target glycemia was achieved by 60 min and remained constant for the duration of the experiment. During the clamp, blood glucose or glucose infusion rates were not different between groups. Whereas beta cell mass was not different between groups, BKO had enhanced beta cell function in vivo, as exhibited by increased insulin secretion; compared to CON, the cumulative circulating insulin during the clamp in BKO was substantially larger (AUC: 340 ± 24 vs. 545 ± 70 ng/ml*120 min). Thus, a loss of Mig6 in beta cells enhances functional beta cell mass by increasing beta cell insulin secretory capacity in vivo. Therefore, Mig6 should be considered as a therapeutic target for diabetes. Disclosure B. M. Bauer: None. E. A. Bloom-saldana: None. J. M. Irimia-dominguez: None. P. T. Fueger: Consultant; Self; Protomer Technologies. Funding National Institutes of Health (R01DK099311)

In vitro α amylase and amyloglucosidase inhibitory activities of selected underutilized cereals, yams and root crops

Diabetes is one of the most challenging global health problems. Currently, reducing postprandial blood glucose concentration by inhibiting carbohydrate hydrolyzing enzymes is recognized as an effective treatment against diabetes. In this study, in vitro α-amylase and amyloglucosidase inhibitory effect of selected, underutilized and locally grown cereals (P. miliaceum, P. scrobiculatum and S. italica), yams (D. alata and D. esculenta) and root crops (L. spinosa and N. nucifera) were evaluated related to their dietary fiber contents. Results showed that the inhibitory effect of selected food crops has a positive correlation with their dietary fiber contents. L. spinosa with higher dietary fiber content generally had higher α-amylase (78.0%) and amyloglucosidase (71.28%) enzyme inhibitory percentages among yams and root crops. Significantly highest (p<0.05) dietary fiber content was in S. italic among three cereal varieties and it showed the highest inhibition activity against α-amylase (67.8%) and amyloglucosidase (59.40%) activity. These tested food crops are considerable sources of dietary fiber and are having α-amylase and amyloglucosidase enzyme inhibitory actions against starch hydrolysis.

A Practical Perspective for a Conservative Estimate of Blood Glucose Level during Restaurant Dining and Supermarket Shopping.

Foods today are so diverse and enjoyable, making healthy choices difficult. In this perspective, an in vitro-in silico approach for obtaining a conservative estimate of the postprandial blood glucose concentration, which is a realistic estimate nevertheless, after intake of a certain portion of meals is proposed. The rationales and feasibilities of the approach are described and discussed to an extent. The key idea is to first measure the maximum amount of glucose released in an in vitro test under standardized conditions from a specified serving size of a meal or dish or a packaged product sold in a supermarket. The value can then be translated by a literate consumer to the highest estimate of blood glucose rise prior to purchasing or eating through an established in silico blood glucose prediction model in the medical field. The strategy proposed here would help health conscious (diabetics included) and other life quality conscious individuals to make quantitative decisions on consuming the portions of different foods of desire. This strategy may be more effective in reality compared to the conventional GI (Glycemic Index) and GL (Glycemic Load) concepts.