Plasma Glucose Responses Research Articles

Effects of three major amino acids found in Japanese broth on glucose metabolism and gastric emptying.

To our knowledge, the effect of the broth of dried kelp and dried bonito, dashi, on glucose metabolism and digestion has rarely been studied. Based on the component analysis of three actual broths served in traditional restaurants, a chemically synthesized broth with three free amino acids (histidine, glutamate, aspartate) and salt was prepared to investigate their effect on glucose metabolism, glucose-dependent insulinotropic polypeptide (GIP), and glucagon-like peptide 1 (GLP-1) secretion, and digestion. In study 1, seven healthy individuals were enrolled in a four-period crossover study. Participants drank or ate hot water, synthesized broth, hot water with rice, and synthesized broth with rice. Plasma glucose, serum insulin, plasma glucagon, plasma GIP, and plasma GLP-1 were measured at baseline and after ingestion. In study 2, 6 of the 7 individuals ingested rice steamed with 13C-labeled sodium acetate with hot water or synthesized broth to estimate gastric emptying by the 13C-labeled acetate breath test in a two-period crossover trial. Ingesting water or synthesized broth alone elicited no change in plasma glucose or serum insulin levels. Ingesting synthesized broth with rice resulted in a rapid rise in plasma glucose and GLP-1 (P=0.01 and 0.02, respectively) in an early postprandial phase compared with that by ingesting water with rice, but the area under the curve of those showed no significant differences. Ingesting synthesized broth with rice resulted in a significantly higher gastric emptying coefficient than that after rice with water (P=0.03). Three amino acids and sodium chloride corresponding to those found in actual broth promoted gastric emptying and led to a rapid response of plasma glucose. Our findings suggest that ingestion of the broth of dried kelp and dried bonito may improve gastric motility.

Reproducibility of the plasma glucose response to moderate-intensity exercise in adolescents with Type 1 diabetes.

The aim of the study was to evaluate the reproducibility of the plasma glucose response to moderate-intensity exercise performed on different days under controlled conditions in adolescents with Type 1 diabetes. Eight adolescents with Type 1 diabetes on continuous subcutaneous insulin infusion completed two exercise sessions, each on two separate days, under basal insulin and fasting conditions. On each day, participants cycled twice for 30 min at 55% of their peak rate of oxygen consumption, with each exercise session separated by a 30-min rest. Plasma insulin levels were similar between testing days and exercise sessions. The mean absolute drop in plasma glucose from the commencement to the end of exercise was 1.6 ± 0.5 mmol/l on day 1 and 1.9 ± 0.7 mmol/l on day 2 (P = 0.3). In response to the first exercise session, plasma glucose levels relative to baseline did not change significantly (0.2 ± 0.6 and -0.2 ± 0.5 mmol/l on days 1 and 2). By contrast, the change in plasma glucose during the second exercise session was -1.1 ± 0.7 and -1.3 ± 0.7mmol/l on days 1 and 2, respectively. The mean absolute intra-individual difference in the change in plasma glucose between testing days were 0.7 ± 0.5 [95% confidence interval (CI) 0.4-1.0] and 0.7 ± 0.4 (95% CI 0.4-1.0) mmol/l, at the end of the first and second exercise sessions respectively. The plasma glucose response to moderate-intensity exercise under similar glycaemic and basal insulin conditions can be reproducible in adolescents with Type 1 diabetes.

Yogurt consumption, body composition, and metabolic health in the Québec Family Study

The aim was to compare the anthropometric and metabolic profiles and lifestyle behaviours of yogurt consumers and non-consumers and to determine if the observed differences persisted after adjustment for diet quality and related variables. Using cross-sectional and follow-up data from the Québec Family Study, men and women were classified into yogurt consumers (n = 269; 96 men and 173 women) and non-consumers (n = 570; 279 men and 291 women), and their anthropometric measurements, metabolic profiles, and lifestyle factors were compared. Men yogurt consumers had a lower body weight, BMI, % body fat, waist circumference and lower plasma insulin, and C-peptide concentrations in response to oral glucose, while women yogurt consumers had lower waist circumference, BMI, % body fat, plasma glucose, insulin, and C-peptide compared with non-consumers (P < 0.05). After adjustment for the Nutrient-Rich Foods (NRF) index, a marker of diet quality, these differences persisted in men and only for glycemic variables in women. Additional adjustment for physical activity participation and % body fat did not abolish the significant differences observed between yogurt consumers and non-consumers for plasma glucose, insulin, and C-peptide responses to oral glucose in women only (P < 0.05). Analyses of data after a 6-year follow-up reinforced these observations, since both men and women yogurt consumers maintained a better metabolic profile compared with non-consumers after adjustments for age and NRF (P < 0.05). In addition, an interaction between group and time for % body fat in men suggests a benefit of yogurt consumption over time on body composition. Yogurt consumption is associated with body composition and metabolic health benefits that are not entirely explained by a global effect of diet quality.

Blood Glucose and Insulin Concentrations after Octreotide Administration in Horses With Insulin Dysregulation.

BackgroundOctreotide is a somatostatin analog that suppresses insulin secretion.HypothesisWe hypothesized that octreotide would suppress insulin concentrations in horses and that normal (N) horses and those with insulin dysregulation (ID) would differ significantly in their plasma glucose and insulin responses to administration of octreotide.AnimalsTwelve horses, N = 5, ID = 7.MethodsProspective study. An oral sugar test was performed to assign horses to N and ID groups. Octreotide (1.0 μg/kg IV) was then administered, and blood was collected at 0, 5, 10, 15, 20, 25, 30, 45, 60, 75, and 90 minute, and 2, 3, 4, 6, 8, 12, and 24 hour for measurement of glucose and insulin concentrations. Area under the curve (AUC) values were calculated.ResultsMean AUC values for glucose and insulin did not differ between normal (n = 5) and ID (n = 7) groups after octreotide injection. Significant time (P < .001) effects were detected for glucose and insulin concentrations. A group × time interaction (P = .091) was detected for insulin concentrations after administration of octreotide, but the group (P = .33) effect was not significant.Conclusions and Clinical ImportanceOctreotide suppresses insulin secretion, resulting in hyperglycemia, and then concentrations increase above baseline as glycemic control is restored. Our hypothesis that octreotide causes insulin concentrations to decrease in horses was supported, but differences between N and ID groups did not reach statistical significance when blood glucose and insulin responses were compared. The utility of an octreotide response test remains to be determined.

Effects of Prior Aerobic Exercise and Prolonged Sitting on Postprandial Plasma Glucose and Triglyceride Responses

Effects of Prior Aerobic Exercise and Prolonged Sitting on Postprandial Plasma Glucose and Triglyceride Responses

Plasma Amino Acid, Glucose and Insulin Response to a Metered Intake of Milk or Carbohydrate‐Electrolyte Solution during 5 h Recovery from Exercise in Healthy Active Young Men

Plasma Amino Acid, Glucose and Insulin Response to a Metered Intake of Milk or Carbohydrate‐Electrolyte Solution during 5 h Recovery from Exercise in Healthy Active Young Men

Diagnostic Performance of 48-Hour Fasting Test and Insulin Surrogates in Patients With Suspected Insulinoma.

This study aimed to evaluate the usefulness of the 48-hour fasting test and insulin surrogates followed by a glucagon stimulatory test (GST) for the diagnosis of insulinoma. Thirty-five patients with suspected insulinoma who underwent 48-hour fasting test and GST were retrospectively included in our study: 15 patients with surgically proven insulinomas and 20 patients in whom insulinoma was clinically ruled out. We determined the duration of the fasting test, plasma glucose levels, serum levels of immunoreactive insulin and C-peptide, and insulin surrogates (serum levels of β-hydroxybutyrate, free fatty acid, and response of plasma glucose to intravenous glucagon [ΔPG]) at the end of the fast. The sensitivity and specificity of the 48-hour fasting test were 100.0% and 80.0%, respectively, for the diagnosis of insulinoma. When the 48-hour fasting test and immunoreactive insulin, C-peptide, or insulin surrogates were combined, the combination with GST showed the best results. The sensitivity, specificity, and accuracy rate were 93.3%, 95.0%, and 94.3%, respectively, with 1 false-negative case and 1 false-positive case occurring. A more accurate and less invasive diagnosis of insulinoma was possible by combining the 48-hour fasting test with the GST, compared with the existing method.

Abnormal Glucose Metabolism and High-Energy Expenditure in Idiopathic Pulmonary Arterial Hypertension.

Insulin resistance has emerged as a potential mechanism related to the pathogenesis of idiopathic pulmonary arterial hypertension (IPAH). However, direct measurements of insulin and glucose metabolism have not been performed in patients with IPAH to date. To perform comprehensive metabolic phenotyping of humans with IPAH. We assessed plasma insulin and glucose, using an oral glucose tolerance test and estimated insulin resistance, and β-cell function in 14 patients with IPAH and 14 control subjects matched for age, sex, blood pressure, and body mass index. Body composition (dual-energy X-ray absorptiometry), inflammation (CXC chemokine ligand 10, endothelin-1), physical fitness (6-min walk test), and energy expenditure (indirect calorimetry) were also assessed. Patients with IPAH had a higher rate of impaired glucose tolerance (57 vs. 14%; P < 0.05) and reduced glucose-stimulated insulin secretion compared with matched control subjects (IPAH: 1.31 ± 0.76 μU/ml⋅mg/dl vs. control subjects: 2.21 ± 1.27 μU/ml⋅mg/dl; P < 0.05). Pancreatic β-cell function was associated with circulating endothelin-1 (r = -0.71, P < 0.01) and CXC chemokine ligand 10 (r = -0.56, P < 0.05). Resting energy expenditure was elevated in IPAH (IPAH: 32 ± 3.4 vs. control subjects: 28.8 ± 2.9 kcal/d/kg fat-free mass; P < 0.05) and correlated with the plasma glucose response (r = 0.51, P < 0.01). Greater insulin resistance was associated with reduced 6-minute walk distance (r = 0.55, P < 0.05). Independent of age, sex, blood pressure, and body mass index, patients with IPAH have glucose intolerance, decreased insulin secretion in response to glucose, and elevated resting energy expenditure. These abnormalities are associated with circulating markers of inflammation and vascular dysfunction.

Responses of plasma glucose and nonesterified fatty acids to intravenous insulin tolerance tests in dairy cows during a 670-day lactation

The metabolic response of dairy cows undergoing an extended lactation to an insulin tolerance test (ITT) was investigated. Twelve multiparous Holstein-Friesian cows that calved in late winter in a pasture-based system were managed for a 670-d lactation by delaying rebreeding. Four 5-wk experimental periods commenced at approximately 73, 217, 422, and 520 d in milk (DIM). Cows were offered a diet of perennial ryegrass (73 and 422 DIM) or pasture hay and silage (217 and 520 DIM) supplemented with 1 kg dry matter (DM) of grain (control; CON) or 6 kg DM of grain (GRN). Daily energy intake was approximately 160 and 215 MJ of metabolizable energy/cow for CON and GRN, respectively. At all other times, cows were managed as a single herd and grazed pasture supplemented with grain to an estimated daily intake of 180 MJ of metabolizable energy/cow. Cows were fitted with a jugular catheter during the final week of each experimental period. An ITT using 0.12 IU of insulin/kg of body weight (BW) was conducted on each cow at approximately 100, 250, 460, and 560 DIM. Cows in the GRN treatment had greater milk yield, milk solids yield, and BW than cows in the CON treatment. Within treatment, individual cow responses to the ITT were highly variable. Plasma glucose and nonesterified fatty acid (NEFA) concentrations declined at all stages of lactation. The clearance rate of plasma glucose was slower before 300 DIM than after 300 DIM, which indicates greater inhibition of hepatic glucose synthesis and uptake of glucose by insulin-dependent tissues later in the lactation. The clearance rate, area under the curve, and recovery of plasma NEFA were greatest at 100 DIM, indicating greater responsiveness to the antilipolytic effect of insulin in early lactation, but also greater lipolytic responsiveness. The variation in response to the ITT was mostly a result of DIM rather than diet. However, the plasma NEFA response showed interactions between diet and DIM, indicating that energy intake may affect tissue responses to insulin. The responsiveness of peripheral tissues to insulin, primarily adipose tissue, changed throughout a 670-d lactation and contributed to a greater proportion of nutrients being partitioned to body reserves at the expense of milk yield as lactation progressed. Both stage of lactation and dietary intake have a role in the determination of whole-body and peripheral tissue responses to insulin; however, the exact mechanisms in control of this are unclear.

Postprandial Glycemic and Insulinemic Responses to Common Breakfast Beverages Consumed with a Standard Meal in Adults Who Are Overweight and Obese

Breakfast beverages with different nutrient compositions may affect postprandial glycemic control differently. We assessed the effects of consuming (1) common breakfast beverages (water, sugar-sweetened coffee, reduced-energy orange juice (OJ), and low-fat milk (LFM)); and (2) fat-free, low-fat, and whole milk with breakfast on postprandial plasma glucose and insulin responses in adults who were overweight/obese. Forty-six subjects (33F/13M, body mass index: 32.5 ± 0.7 kg/m2, age: 50 ± 1 years, mean ± SEMs) consumed a standard sandwich with one of the six beverages on separate mornings in randomized order. The test beverages (except water) each contained 12 g digestible carbohydrate. Plasma glucose and insulin concentrations were measured from blood obtained pre- and post-meal at 30-min intervals for 4 h and incremental areas under the curve (AUC) were computed. We found (1) among different beverage types, glucose AUC was higher for coffee versus water, OJ, and LFM. Insulin AUC was higher for coffee and LFM versus OJ and water; (2) Glucose AUCs were not different among water and milks while insulin AUC was higher for milks versus water. In conclusion, consumption of water, reduced-energy OJ, or milk (irrespective of fat content) with a meal may be preferable to consuming sugar-sweetened coffee for glucose control in middle-aged adults who are overweight and obese.

Improved Postprandial Glycemic Control with Faster-Acting Insulin Aspart in Patients with Type 1 Diabetes Using Continuous Subcutaneous Insulin Infusion.

Background: Faster aspart is insulin aspart (IAsp) in a new formulation, which in continuous subcutaneous insulin infusion (CSII) in subjects with type 1 diabetes has shown a faster onset and offset of glucose-lowering effect than IAsp.Methods: This double-blind, randomized, crossover active-controlled trial compared 2-h postprandial plasma glucose (PPG) response, following 2 weeks of CSII with faster aspart or IAsp. Primary endpoint: mean change in PPG 2 h after a standardized meal test (ΔPGav,0–2h). Subjects (n = 43) had masked continuous glucose monitoring (CGM) throughout.Results: Faster aspart provided a statistically significantly greater glucose-lowering effect following the meal versus IAsp: ΔPGav,0–2h: 3.03 mmol/L versus 4.02 mmol/L (54.68 mg/dL vs. 72.52 mg/dL); estimated treatment difference (ETD) [95% CI]: −0.99 mmol/L [–1.95; −0.03] (−17.84 mg/dL [–35.21; −0.46]; P = 0.044). One hour postmeal, PG levels were −1.64 mmol/L (−29.47 mg/dL) lower with faster aspart versus IAsp (P = 0.006). Interstitial glucose (IG) profiles supported these findings; the largest differences were observed at breakfast: 9.08 versus 9.56 mmol/L (163.57 vs. 172.19 mg/dL; ETD [95% CI]: −0.48 mmol/L [–0.97; 0.01]; −8.62 mg/dL [–17.49; 0.24]; P = 0.057). Duration of low IG levels (≤3.9 mmol/L [70 mg/dL] per 24 h) was statistically significantly shorter for faster aspart versus IAsp (2.03 h vs. 2.45 h; ETD [95% CI]: −0.42 [–0.72; −0.11]; P = 0.008). No unexpected safety findings were observed.Conclusions: CSII delivery of faster aspart had a greater glucose-lowering effect than IAsp after a meal test. CGM results recorded throughout all meals supported this finding, with less time spent with low IG levels.

Phytochemical Pharmacokinetics and Bioactivity of Oat and Barley Flour: A Randomized Crossover Trial.

While dietary fiber plays an important role in the health benefits associated with whole grain consumption, other ingredients concentrated in the outer bran layer, including alkylresorcinols, lignans, phenolic acids, phytosterols, and tocols, may also contribute to these outcomes. To determine the acute bioavailability and pharmacokinetics of the major phytochemicals found in barley and oats, we conducted a randomized, three-way crossover trial in 13 healthy subjects, aged 40–70 years with a body mass index (BMI) of 27–35.9 kg/m2. After a two-day run-in period following a diet low in phytochemicals, subjects were randomized to receive muffins made with either 48 g whole oat flour, whole barley flour, or refined wheat flour plus cellulose (control), with a one-week washout period between each intervention. At the same time, an oral glucose tolerance test was administered. In addition to plasma phytochemical concentrations, glucose and insulin responses, biomarkers of antioxidant activity, lipid peroxidation, inflammation, and vascular remodeling were determined over a 24-h period. There was no significant effect on acute bioavailability or pharmacokinetics of major phytochemicals. Administered concurrently with a glucose bolus, the source of whole grains did not attenuate the post-prandial response of markers of glucoregulation and insulin sensitivity, inflammation, nor vascular remodeling compared to the refined grain control. No significant differences were observed in the bioavailability or postprandial effects between whole-oat and whole-barley compared to a refined wheat control when administered with a glucose challenge. These null results may be due, in part, to the inclusion criteria for the subjects, dose of the whole grains, and concurrent acute administration of the whole grains with the glucose bolus.

Meal rich in carbohydrate, but not protein or fat, reveals adverse immunometabolic responses associated with obesity.

BackgroundObesity-related insulin resistance is linked to inflammation. Immunometabolic function differs between lean and obese subjects, but whether macronutrient composition of ingested meals affects these responses is not well known. We examined the effects of a single meal rich in fat, protein, or carbohydrate on immunometabolic responses.MethodsNine lean insulin sensitive (LIS) men and 9 obese insulin resistant (OIR) men ingested high-carbohydrate (HC), high-fat (HF) or high-protein (HP) mixed meals in random order. We assessed plasma glucose, insulin, and cytokine responses and cytokine gene expression in circulating mononuclear cells (MNC) at fasting and postprandial states (up to 6-h).ResultsExpression of NF-κB and TNFα genes were greater; whereas that of TGFβ and IL-6 genes were lower, in the OIR compared to the LIS individuals. The differences were significantly greater after the HC meal, but not after the HP or HF meal. Similar results were obtained for plasma concentrations of TNFα and IL-6.ConclusionsOur findings indicate that a single HC meal has a distinct adverse effect on immunometabolic responses in the OIR individuals. The cumulative effect of such adverse responses to meals rich in carbohydrate may predispose the OIR individuals to a higher risk of cardiovascular disease.Electronic supplementary materialThe online version of this article (doi:10.1186/s12937-016-0219-0) contains supplementary material, which is available to authorized users.

Inorganic Nitrate Supplementation in Young and Old Obese Adults Does Not Affect Acute Glucose and Insulin Responses but Lowers Oxidative Stress

Background: Aging and obesity are associated with raised oxidative stress and a reduction of nitric oxide (NO) bioavailability, with subsequent decline in insulin sensitivity and endothelial function. Inorganic nitrate is converted into NO via a 2-step reduction process and may be an effective nutritional intervention to modify vascular and metabolic functions.Objectives: This study tested whether inorganic nitrate supplementation improved glucose disposal and attenuated the acute effects of hyperglycemia on oxidative stress, inflammation, and vascular function in young and old obese participants.Methods: Ten young (aged 18–44 y) and 10 old (aged 55–70 y) obese participants consumed 75 g glucose followed by either potassium nitrate (7 mg/kg body weight) or potassium chloride (placebo) in a randomized, double-blind crossover design. Resting blood pressure (BP), endothelial function, and blood biomarkers were measured for 3 h postintervention. Biomarkers included plasma nitrate/nitrite (NOx), glucose, insulin, cyclic GMP, interleukin 6, 3-nitrotyrosine, E- and P-selectins, intercellular adhesion molecule 3 (ICAM-3), and thrombomodulin, as well as superoxide in freshly isolated peripheral blood mononuclear cells (PBMCs).Results: Inorganic nitrate supplementation did not affect plasma glucose (P = 0.18) or insulin (P = 0.26) responses. The increase in plasma NOx concentrations 3 h after the administration of inorganic nitrate was significantly higher in young than in old participants (234% increase compared with 149% increase, respectively, P < 0.001). Plasma 3-nitrotyrosine concentrations declined significantly after inorganic nitrate supplementation compared with placebo (3 h postdose, 46% decrease compared with 27% increase, respectively, P = 0.04), and a similar nonsignificant trend was observed for superoxide concentrations (3 h postdose, 16% decrease compared with 23% increase, respectively, P = 0.06). Plasma cyclic GMP, ICAM-3, and thrombomodulin concentrations differed between young and old participants (P < 0.01). Inorganic nitrate supplementation did not improve BP or endothelial function.Conclusions: Oral supplementation with inorganic nitrate did not improve glucose and insulin responses but reduced oxidative stress in old individuals during acute hyperglycemia. This trial was registered at http://www.controlled-trials.com as ISRCTN42776917.

Insulin Sensitivity and Plasma Glucose Response to Aerobic Exercise in Pregnant Women at Risk for Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is one of the common complications that occur during pregnancy. Early intervention is essential to prevent the development of the disease in the non-pregnant state but also helpful in preventing the occurrence of GDM. The aim of the study was to assess the effect of aerobic exercises on insulin sensitivity and fasting plasma glucose level in pregnant women with risk for gestational diabetes mellitus. Forty multigravidae women between 20-24 weeks of gestation with risk for GDM were randomly selected (age range was 25-35 years), body mass index ranged from 30-35 kg/m2. Women were divided into two equal groups: intervention group (A), which followed an aerobic exercise program in the form of walking on treadmill, three times weekly until the end of 37 weeks of gestation in addition to diet control. Control group (B) which received diet control with usual care given by obstetricians and midwives. Evaluation of the women in both groups was carried out before and after treatment program through assessment of fasting blood glucose and insulin levels. There was a highly statistically significance decrease in fasting blood glucose level, fasting insulin level in both groups where the p value was 0.0001 favoring group (A). Moderate intensity of aerobic exercises were effective in reducing fasting blood glucose level and fasting insulin level in pregnant women with risk for gestational diabetes mellitus.

Drinks containing anthocyanin-rich blackcurrant extract decrease postprandial blood glucose, insulin and incretin concentrations

Blackcurrants are rich in polyphenolic glycosides called anthocyanins, which may inhibit postprandial glycemia. The aim was to determine the dose-dependent effects of blackcurrant extract on postprandial glycemia. Men and postmenopausal women (14M, 9W, mean age 46 years, S.D.=14) were enrolled into a randomized, double-blind, crossover trial. Low sugar fruit drinks containing blackcurrant extract providing 150-mg (L-BE), 300-mg (M-BE) and 600-mg (H-BE) total anthocyanins or no blackcurrant extract (CON) were administered immediately before a high-carbohydrate meal. Plasma glucose, insulin and incretins (GIP and GLP-1) were measured 0–120min, and plasma 8-isoprostane F2α, together with arterial stiffness by digital volume pulse (DVP) was measured at 0 and 120min. Early plasma glucose response was significantly reduced following H-BE (n=22), relative to CON, with a mean difference (95% CI) in area over baseline (AOB) 0-30min of −0.34mmol/l.h (−0.56, −0.11, P<.005); there were no differences between the intermediate doses and placebo. Plasma insulin concentrations (AOB 0–30min) were similarly reduced. Plasma GIP concentrations (AOB 0–120min) were significantly reduced following H-BE, with a mean difference of −46.6ng/l.h (−66.7, −26.5, P<.0001) compared to CON. Plasma GLP-1 concentrations were reduced following H-BE at 90min. There were no effects on 8-isoprostane F2α or vascular function. Consumption of blackcurrant extract in amounts roughly equivalent to 100-g blackcurrants reduced postprandial glycemia, insulinemia and incretin secretion, which suggests that inclusion of blackcurrant polyphenols in foods may provide cardio-metabolic health benefits. This trial was registered at clinicaltrials.gov as NCT01706653.

Sex differences in adult rat insulin and glucose responses to arginine: programming effects of neonatal separation, hypoxia, and hypothermia.

Acute neonatal hypoxia, a common stressor, causes a spontaneous decrease in body temperature which may be protective. There is consensus that hypothermia should be prevented during acute hypoxia in the human neonate; however, this may be an additional stress with negative consequences. We hypothesize that maintaining body temperature during hypoxia in the first week of postnatal life alters the subsequent insulin, glucose, and glucagon secretion in adult rats. Rat pups were separated from their dam daily from postnatal days (PD) 2–6 for the following 90 min experimental treatments: (1) normoxic separation (control), (2) hypoxia (8% O2) allowing spontaneous hypothermia, (3) normoxic hypothermia with external cold, and (4) exposure to 8% O2 while maintaining body temperature using external heat. An additional normoxic non‐separated control group was performed to determine if separation per se changed the adult phenotype. Plasma insulin, glucose, and glucagon responses to arginine stimulation were evaluated from PD105 to PD133. Maternal separation (compared to non‐separated neonates) had more pronounced effects on the adult response to arginine compared to the hypoxic, hypothermic, and hypoxic‐isothermic neonatal treatments. Adult males exposed to neonatal maternal separation had augmented insulin and glucose responses to arginine compared to unseparated controls. Additionally, neonatal treatment had a significant effect on body weight gain; adults exposed to neonatal maternal separation were significantly heavier. Female adults had significantly smaller insulin and glucose responses to arginine regardless of neonatal treatment. Neonatal maternal separation during the first week of life significantly altered adult beta‐cell function in a sexually dimorphic manner.

Effects of dietary fat subtypes on glucose homeostasis during pregnancy in rats.

BackgroundDietary n-3 and n-6 polyunsaturated fatty acids (PUFAs) have an impact on insulin secretion and sensitivity but whether and how these may be related to maternal glucose homeostasis during pregnancy is unclear.MethodsFemale Wistar rats (240–250 g) were assigned to laboratory CHOW or high fat diets rich in either n-6 (safflower oil; n-6 group) or n-6 + n-3 (safflower oil + fish oil; n-3 group) PUFAs. After 10 days half of the animals in each diet group were inseminated and confirmed pregnant. An overnight fasted intravenous glucose tolerance test (500 mg glucose/kg body weight) was performed on chronically cannulated non-pregnant and 20-day pregnant rats. Indices of insulin secretion (β) and insulin sensitivity (S) were calculated from the plasma glucose and insulin responses. The fatty acid composition of phospholipids was determined in samples of liver and two skeletal muscles (soleus and red quadriceps).ResultsPregnancy in the CHOW group significantly increased β (P < 0.001) and decreased S (P < 0.01). In contrast, both n-6 and n-3 diets abolished both the pregnancy-induced decrease in S and pregnancy-induced increase in β with the n-3 diet having a more potent effect on both S and β. S was positively correlated with the sum of n-3 fatty acids, with docosahexaenoic acid (22:6 n-3) the major contributor, in liver (r = 0.485; P < 0.001), red quadriceps (r = 0.421; P = 0.004) and soleus (r = 0.476; P < 0.001). In contrast S was inversely related to arachidonic acid (20:4n-6) levels in liver and red quadriceps across all groups and these relationships were particularly powerful in pregnancy (liver: r = -0.785; red quadriceps: r = -0.754, both P < 0.0001).ConclusionsThe results demonstrate potent effects of dietary fat amount and profile on glucoregulation during pregnancy and emphasize the importance of the balance between dietary n-3 and n-6 PUFAs.Electronic supplementary materialThe online version of this article (doi:10.1186/s12986-016-0117-7) contains supplementary material, which is available to authorized users.

Plasma glucose and insulin response to two oral nutrition supplements in adults with type 2 diabetes mellitus.

ObjectiveThe purpose of this clinical trial was to compare the glucose usage of two oral nutritional supplement (ONS) products and to assess whether a diabetes-specific formulation provides improved glucose stabilization and management compared with a standard formula.Research design and methodsA total of 12 subjects with type 2 diabetes (7 males and 5 females) completed a randomized, cross-over design trial. Each subject consumed isocaloric amounts of either the standard ONS or the diabetes-specific formula ONS on different dates, 1 week apart. Glucose and insulin measures were recorded at baseline, and 10, 20, 30, 60, 90, 120, 150, 180, 210 and 240 min after the beverage was consumed and then used to calculate area under the curve (AUC) for each subject.ResultsThe mean glucose AUC was lower in the diabetes-specific ONS group than in the standard group (p<0.0001), but there was not a significant difference observed for mean insulin AUC (p=0.068). A sensitivity analysis of the mean insulin AUC measures was performed by removing a potential outlier from the analysis, and this resulted in a significant difference between the groups (p=0.012). First-phase insulin measures and an insulinogenic index calculated for the beverages showed no significant differences.ConclusionsOn the basis of the results of this trial of 12 subjects, the diabetes-specific ONS appears to provide better glucose maintenance in persons with type 2 diabetes when compared to the standard formula ONS.Trial registration numberNCT02612675.

The effect of the glycaemic response of three commonly consumed meals on postprandial plasma glucose in type 2 diabetics at the University of Nigeria Teaching Hospital, Enugu

Objectives: This study evaluated the glycaemic response of three commonly consumed meals, and the resultant effect on postprandial plasma glucose response in type 2 diabetes mellitus patients at the University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Nigeria.Design: This was an experimental study on 100 consenting type 2 diabetes mellitus patients who were on medical nutrition therapy only, attending the University of Nigeria Teaching Hospital medical outpatient clinic between May 2012 and March 2013.Subjects and setting: One hundred non-diabetic healthy University of Nigeria Teaching Hospital workers served as the control. Participants consumed served portions of each meal containing 50 g of glycaemic carbohydrate. Only the control consumed 50 g glucose to establish glycaemic response. The three test meals comprised pap and bambara nut pudding; meat and okro soup with fermented cassava dough; and meat, beans and corn pottage with spinach.Outcome measures: Plasma glucose was measured quarter hourly, for two hours, from which glycaemic index (GI) and glycaemic load (GL) values were calculated per serving.Results: Two meals, namely meat, beans and corn pottage with spinach; and pap and bambara nut pudding; provided a lower glycaemic response and reduced postprandial plasma glucose peak compared to meat and okro soup with fermented cassava dough at 30, 45, 60, 90 and 120 minutes in non-diabetic and type 2 diabetes mellitus patients (p-value < 0.050). The lowest GI and GL values per serving were attributed to the meat, beans and corn pottage with spinach (33.00 ± 1.25 and 4.76 ± 0.67), while the highest respective values were found for the meat and okro soup with fermented cassava dough (74.50 ± 4.91 and 21.59 ± 1.06).Conclusion: Compared to the other two meals, the meal of meat, beans and corn pottage with spinach resulted in a lower glycaemic response, reduced postprandial plasma glucose in non-diabetic and type 2 diabetes mellitus patients, and constituted a healthy alternative to the other two.