Glucose absorption in gestational diabetes mellitus during an oral glucose tolerance test

A self-powered ingestible wireless biosensing system for real-time in situ monitoring of gastrointestinal tract metabolites

Information related to the diverse and dynamic metabolite composition of the small intestine is crucial for the diagnosis and treatment of various diseases. However, our current understanding of the physiochemical dynamics of metabolic processes within the small intestine is limited due to the lack of in situ access to the intestinal environment. Here, we report a demonstration of a battery-free ingestible biosensing system for monitoring metabolites in the small intestine. As a proof of concept, we monitor the intestinal glucose dynamics on a porcine model. Battery-free operation is achieved through a self-powered glucose biofuel cell/biosensor integrated into a circuit that performs energy harvesting, biosensing, and wireless telemetry via a power-to-frequency conversion scheme using magnetic human body communication. Such long-term biochemical analysis could potentially provide critical information regarding the complex and dynamic small intestine metabolic profiles.

Incidence and status of insulin secretion in pregnant women with flat plasma glucose profiles during oral glucose tolerance test

OBJECTIVES

Flat shaped glucose curves (FC) during oral glucose tolerance test (OGTT) in pregnant women (PW) are a not uncommon finding. We aimed to define the FC incidence in a large PW cohort and to describe the status of insulin and C-peptide secretion in women with FC when compared with a well-matched control group.

METHODS

1050 PW performing OGTT for gestational diabetes screening were enrolled. An increase <6 % in plasma glucose (PG) during OGTT defined a FC. Serum samples for measuring insulin and C-peptide were also obtained.

RESULTS

61 (5.8 %) women showed a FC. 60 of them, paired to a group of 60 no-FC women matched for age, body mass index and gestational age, were further investigated. C-peptide and insulin concentrations were significantly lower (P < 0.001) in FC in both 1-h and 2-h OGTT samples. When incremental area under the curves (AUC) normalized to PG were estimated, only AUCinsulin remained however significantly lower. The insulin sensitivity index was higher in FC.

CONCLUSIONS

PW with FC showed a hypersensitivity to insulin with normal β-cell function. Moreover, a delayed glucose absorption could be hypothesised because of the slight but continuously increasing shape of insulin curve found in FC group. Both phenomena could occur in parallel and contribute to FC.

Chronic lead exposure exacerbates hepatic glucolipid metabolism disorder and gut microbiota dysbiosis in high-fat-diet mice

Lead (Pb) and obesity are co-occurring risk factors for metabolic disorders. However, there is still a lack of study on the combined effects of both stressors on metabolism. C57BL/6J mice were exposed to 200 mg/L Pb or/and HFD for 24 weeks and were used to investigate the effects and underlying mechanisms of chronic Pb exposure on obese mice. The results showed that Pb significantly increased body weight, visceral obesity, fasting blood glucose levels, and insulin resistance, and aggravated liver damage, hepatic lipid accumulation and steatosis in HFD-fed mice. Further analysis showed that Pb significantly inhibited insulin signaling pathway PI3K/AKT and fatty acid β-oxidation, and accelerated fatty acid synthesis. Moreover, Pb exacerbated HFD-induced disruption of gut microbiota homeostasis, manifested by increased proportions of pathogenic genera such as Desulfovibrio, Alistipes and Helicobacter, and decreased proportions of beneficial microbes Akkermansia and Barnesiella, which were negatively associated with obesity. These results indicated that Pb exposure exacerbated the disruption of liver glucolipid metabolism in HFD mice possibly by disrupting gut microbiota.

Use of prokineticin-1 (PROK1), pregnancy-associated plasma protein A (PAPP-A) and PROK1/PAPP-A ratio to predict adverse pregnancy outcomes in the first trimester: a prospective study

INTRODUCTION

To compare the predictive effectiveness levels of prokineticin-1 (PROK1), pregnancy-associated plasma protein A (PAPP-A) and the PROK1/PAPP-A ratio in the first trimester for preeclampsia (PE), foetal growth restriction (FGR), gestational diabetes mellitus (GDM) and spontaneous preterm birth (SPB).

MATERIALS AND METHODS

A total of randomly selected 162 pregnant women were included. Peripheral blood samples were obtained between 11^0/7 and 13^6/7 gestational weeks (GWs). All women were followed throughout the pregnancy and classified into five groups as having PE, FGR, GDM, SPB and uncomplicated pregnancies. The cut-off levels of the markers were identified to predict adverse outcomes.

RESULTS

PROK1 predicted PE with 83.3% sensitivity, 85.7% specificity at a value of >293.4 pg/mL; at a value of >260.2 pg/mL, PROK1 predicted FGR with 85.7% sensitivity, 72.5% specificity in the first trimester. The area under receiver operating characteristic (ROC) curve of PAPP-A was lower than that of PROK1 and PROK1/PAPP-A in differentiating PE and FGR from the uncomplicated group (p < .001). PROK1 levels and the PROK1/PAPP-A ratios in the SPB and GDM groups were lower than in the uncomplicated group (p < .01).

CONCLUSIONS

Elevated PROK1 in the first trimester is a more effective marker than PAPP-A in the prediction of PE and FGR. Lower PROK1 levels are associated with the development of SPB and GDM.

[Sex- and gender-aspects in regard to clinical practice recommendations for pre-diabetes and diabetes]

Metabolic diseases dramatically affect life of men and women from infancy up to old age and are a major challenge for clinicians. Health professionals are confronted with different needs of women and men. This article aims at an increase of gender awareness and the implementation of current knowledge of gender medicine in daily clinical practice with regard to pre-diabetes and diabetes. Sex and gender affect screening and diagnosis of metabolic diseases as well as treatment strategies and outcome. Impaired glucose and lipid metabolism, regulation of energy balance and body fat distribution are related to steroid hormones and therefore impose their influence on cardiovascular health in both men and women. Furthermore, education, income and psychosocial factors relate to development of obesity and diabetes differently in men and women. Males appear to be at greater risk of diabetes at younger age and at lower BMI compared to women, but women feature a dramatic increase of their cardiometabolic risk after menopause. The estimated future years of life lost owing to diabetes is somewhat higher in women than men, with higher increase of vascular death in women, but higher increase of cancer death in men. In women pre-diabetes or diabetes are more distinctly associated with a higher number of vascular risk factors, such as inflammatory parameters, unfavourable changes of coagulation and blood pressure. Pre-diabetic and diabetic women are at much higher relative risk for vascular disease. Women are more often obese and less physically active, but may even have greater benefit from increased physical activity than males. Whereas men predominantly feature impaired fasting glucose, women often show impaired glucose tolerance. A history of gestational diabetes or the presence of a PCOS or increased androgen levels in women, on the other hand the presence of erectile dysfunction (ED) or decreased testosterone levels in men are sex specific risk factors for diabetes development. ED is a common feature of obese men with the Metabolic Syndrome and an important predictor of cardiovascular disease. Diabetic women also feature sexual dysfunctions much more frequently than non-diabetic women which should be addressed in clinical care. Several studies showed that diabetic women reach their targets of metabolic control (HbA1c), blood pressure and LDL-cholesterol less often than their male counterparts, although the reasons for worse treatment outcome in diabetic females are not clear. Furthermore, sex differences in action, pharmacokinetics, and side effects of pharmacological therapy have to be taken into account.

Neck circumference might predict gestational diabetes mellitus in Han Chinese women: A nested case-control study

AIMS/INTRODUCTION

A large neck circumference might be an indicator of metabolic syndrome and its components, and for certain patients is more practical as an index than waist circumference. The demarcation value for neck circumference that suggests metabolic syndrome appears to vary by ethnic group. Gestational diabetes mellitus is considered a component of metabolic syndrome in pregnant women. We investigated whether neck circumference in Han Chinese women is associated with gestational diabetes mellitus in early pregnancy, and determined a predictive demarcation value.

MATERIALS AND METHODS

A nested case-control study was carried out with 255 women aged 18-35 years. Gestational diabetes mellitus was diagnosed according to the criteria of the American Diabetes Association through a 2-h, 75-g oral glucose tolerance test.

RESULTS

Of the total population, 41 (16%) women developed gestational diabetes mellitus by 24-28 weeks of gestation. Neck circumference at gestational week 16 positively correlated with pre-pregnancy waist circumference, bodyweight and body mass index, and maternal age (P = 0.029) and hemoglobin A1c at gestational week 24 (P ≤ 0.001). By binary logistic regression, neck circumference was an independent predictor of gestational diabetes mellitus (odds ratio 1.840, 95% confidence interval 1.040-3.254; P = 0.036). According to the receiver operating characteristic curve, for predicting gestational diabetes mellitus the optimal demarcation for neck circumference at gestational week 16 was 35.15 cm.

CONCLUSIONS

Neck circumference is a viable tool to screen for gestational diabetes mellitus. In this population of pregnant Han Chinese women, a neck circumference of ≥35.15 cm was a predictor of gestational diabetes mellitus.

Gender-based differences in glycaemic control and hypoglycaemia prevalence in patients with type 2 diabetes: results from patient-level pooled data of six randomized controlled trials

AIMS

To determine the impact of gender on glycaemic control and hypoglycaemia in insulin-naïve patients with type 2 diabetes (T2DM).

METHODS

Data were pooled from six randomized clinical trials of insulin glargine or NPH insulin in insulin-naïve, inadequately controlled patients. Female [n = 1251; mean glycated haemoglobin (HbA1c) level 8.99%, age 56.91 years, diabetes duration 9.84 years] and male patients (n = 1349; mean HbA1c 8.9%, age 57.47 years, diabetes duration 10.13 years) were started on and treated with insulin glargine or NPH insulin for 24-36 weeks. HbA1c and fasting blood glucose levels, percent achieving HbA1c target of <7% and insulin dose change were recorded.

RESULTS

For both men and women, HbA1c levels were significantly reduced over time (p < 0.001); a significantly greater HbA1c reduction was observed in men than in women (-1.36 vs. -1.22; p = 0.002). Significantly fewer women achieved target HbA1c of <7% (p < 0.001). At the study end, women had a significantly higher insulin dose/kg than men (0.47 vs. 0.42 U/kg; p < 0.001). The incidence rates of severe and severe nocturnal hypoglycaemia were significantly higher in women (3.28% vs. 1.85%; p < 0.05 and 2.24% vs. 0.59%; p < 0.001, respectively). Women were more likely to experience severe hypoglycaemia [odds ratio (OR) 1.80; 95% confidence interval (CI) 1.08, 3.00; p = 0.02] and severe nocturnal hypoglycaemia (OR: 3.80; 95% CI 1.72, 8.42; p = 0.001).

CONCLUSIONS

These observations confirm studies that found a smaller improvement in HbA1c and greater hypoglycaemia in women during insulin treatment. Physicians should be aware of the need to determine and closely monitor dosing, particularly in women, to optimize the balance between glycaemic control and hypoglycaemia risk.

Whole-body insulin sensitivity rather than body-mass-index determines fasting and post-glucose-load growth hormone concentrations

Background

Obese, non-acromegalic persons show lower growth hormone (GH) concentrations at fasting and reduced GH nadir during an oral glucose tolerance test (OGTT). However, this finding has never been studied with regard to whole-body insulin-sensitivity as a possible regulator.

Methods

In this retrospective analysis, non-acromegalic (NonACRO, n = 161) and acromegalic (ACRO, n = 35), non-diabetic subjects were subdivided into insulin-sensitive (IS) and –resistant (IR) groups according to the Clamp-like Index (CLIX)-threshold of 5 mg·kg⁻¹·min⁻¹ from the OGTT.

Results

Non-acromegalic IS (CLIX: 8.8±0.4 mg·kg⁻¹·min⁻¹) persons with similar age and sex distribution, but lower (p<0.001) body-mass-index (BMI = 25±0 kg/m², 84% females, 56±1 years) had 59% and 70%, respectively, higher (p<0.03) fasting GH and OGTT GH area under the curve concentrations than IR (CLIX: 3.5±0.1 mg·kg⁻¹·min⁻¹, p<0.001) subjects (BMI = 29±1 kg/m², 73% females, 58±1 years). When comparing on average overweight non-acromegalic IS and IR with similar anthropometry (IS: BMI: 27±0 kg/m², 82% females, 58±2 years; IR: BMI: 27±0 kg/m², 71% females, 60±1 years), but different CLIX (IS: 8.7±0.9 vs. IR: 3.8±0.1 mg·kg⁻¹·min⁻¹, p<0.001), the results remained almost the same. In addition, when adjusted for OGTT-mediated glucose rise, GH fall was less pronounced in IR. In contrast, in acromegalic subjects, no difference was found between IS and IR patients with regard to fasting and post-glucose-load GH concentrations.

Conclusions

Circulating GH concentrations at fasting and during the OGTT are lower in non-acromegalic insulin-resistant subjects. This study seems the first to demonstrate that insulin sensitivity rather than body-mass modulates fasting and post-glucose-load GH concentrations in non-diabetic non–acromegalic subjects.

Impact of glucose tolerance status, sex, and body size on glucose absorption patterns during OGTTs

OBJECTIVE

We studied whether patterns of glucose absorption during oral glucose tolerance tests (OGTTs) were abnormal in individuals with impaired glucose regulation and whether they were related to sex and body size (height and fat-free mass). We also examined how well differences in insulin sensitivity and β-cell function measured by gold-standard tests were reflected in the corresponding OGTT-derived estimates.

RESEARCH DESIGN AND METHODS

With validated methods, various aspects of glucose absorption were estimated from 12-point, 3-h, 75-g OGTTs in 66 individuals with normal glucose tolerance (NGT), isolated impaired fasting glucose (i-IFG), or isolated impaired glucose tolerance (i-IGT). Insulin sensitivity and β-cell function were measured with the euglycemic-hyperinsulinemic clamp and intravenous glucose tolerance tests, respectively. Surrogate markers of both conditions were calculated from OGTTs.

RESULTS

More rapid glucose absorption (P ≤ 0.036) and reduced late glucose absorption (P ≤ 0.039) were observed in the i-IFG group relative to NGT and i-IGT groups. Women with i-IGT had a lower early glucose absorption than did men with i-IGT (P = 0.041); however, this difference did not persist when differences in body size were taken into account (P > 0.28). Faster glucose absorption was related to higher fasting (P = 0.001) and lower 2-h (P = 0.001) glucose levels and to greater height and fat-free mass (P < 0.001). All OGTT-derived measures of insulin sensitivity, but only one of three measures of β-cell function, reflected the differences for these parameters between those with normal and impaired glucose regulation as measured by gold-standard tests.

CONCLUSIONS

Glucose absorption patterns during an OGTT are significantly related to plasma glucose levels and body size, which should be taken into account when estimating β-cell function from OGTTs in epidemiological studies.

Adequately adapted insulin secretion and decreased hepatic insulin extraction cause elevated insulin concentrations in insulin resistant non-diabetic adrenal incidentaloma patients

Background

Insulin-resistance is commonly found in adrenal incidentaloma (AI) patients. However, little is known about beta-cell secretion in AI, because comparisons are difficult, since beta–cell-function varies with altered insulin-sensitivity.

Objectives

To retrospectively analyze beta–cell function in non-diabetic AI, compared to healthy controls (CON).

Methods

AI (n=217, 34%males, 57±1years, body-mass-index:27.7±0.3kg/m²) and CON [n=25, 32%males, 56±1years, 26.7±0.8kg/m²] with comparable anthropometry (p≥0.31) underwent oral-glucose-tolerance-tests (OGTTs) with glucose, insulin, and C–peptide measurements. 1mg-dexamethasone-suppression-tests were performed in AI. AI were divided according to post–dexamethasone-suppression–test cortisol-thresholds of 1.8 and 5µg/dL into 3subgroups: pDexa<1.8µg/dL, pDexa1.8-5µg/dL and pDexa>5µg/dL. Using mathematical modeling, whole-body insulin-sensitivity [Clamp-like-Index (CLIX)], insulinogenic Index, Disposition Index, Adaptation Index, and hepatic insulin extraction were calculated.

Results

CLIX was lower in AI combined (4.9±0.2mg·kg^-1·min^-1), pDexa<1.8µg/dL (4.9±0.3) and pDexa1.8-5µg/dL (4.7±0.3, p<0.04 vs.CON:6.7±0.4). Insulinogenic and Disposition Indexes were 35%–97% higher in AI and each subgroup (p<0.008 vs.CON), whereas C–peptide–derived Adaptation Index, compensating for insulin-resistance, was comparable between AI, subgroups, and CON. Mathematical estimation of insulin–derived (insulinogenic and Disposition) Indexes from associations to insulin-sensitivity in CON revealed that AI-subgroups had ~19%-32% higher insulin-secretion than expectable. These insulin-secretion-index differences negatively (r=-0.45, p<0.001) correlated with hepatic insulin extraction, which was 13-16% lower in AI and subgroups (p<0.003 vs.CON).

Conclusions

AI-patients show insulin-resistance, but adequately adapted insulin secretion with higher insulin concentrations during an OGTT, because of decreased hepatic insulin extraction; this finding affects all AI-patients, regardless of dexamethasone-suppression-test outcome.

[Sex- and gender-aspects in regard to clinical practice recommendations for pre-diabetes and diabetes]

Metabolic diseases dramatically affect life of men and women from infancy up to old age and are a major challenge for clinicians. Health professionals are confronted with different needs of women and men. This article aims at an increase of gender awareness and the implementation of current knowledge of gender medicine in daily clinical practice with regard to pre-diabetes and diabetes. Sex and gender affect screening and diagnosis of metabolic diseases as well as treatment strategies and outcome. Impaired glucose and lipid metabolism, regulation of energy balance and body fat distribution are related to steroid hormones and therefore impose their influence on cardiovascular health in both men and women. Furthermore, education, income and psychosocial factors relate to development of obesity and diabetes differently in men and women. Males appear to be at greater risk of diabetes at younger age and at lower BMI compared to women, but women feature a dramatic increase of their cardiometabolic risk after menopause. The estimated future years of life lost owing to diabetes is somewhat higher in women than men, with higher increase of vascular death in women, but higher increase of cancer death in men. In women pre-diabetes or diabetes are more distinctly associated with a higher number of vascular risk factors, such as inflammatory parameters, unfavourable changes of coagulation and blood pressure. Pre-diabetic and diabetic women are at much higher risk for vascular disease (3-6 times compared to non-diabetic women) than diabetic men (2-3 times compared to healthy males). Women are more often obese and less physically active, but may even have greater benefit from increased physical activity than males. Whereas men predominantly feature impaired fasting glucose, women often show impaired glucose tolerance. A history of gestational diabetes or the presence of a PCOS or increased androgen levels in women, on the other hand the presence of erectile dysfunction (ED) or decreased testosterone levels in men are sex specific risk factors for diabetes development. ED is a common feature of obese men with the Metabolic Syndrome and an important predictor of cardiovascular disease. Several studies showed that diabetic women reach their targets of metabolic control (HbA1c), blood pressure and LDL-cholesterol less often than their male counterparts, although the reasons for worse treatment outcome in diabetic females are not clear. Furthermore, sex differences in action, pharmacokinetics, and side effects of pharmacological therapy have to be taken into account.

Disorders in glucidic metabolism and congenital heart diseases: detection and prevention

The identification of gestational diabetes (GDM) through appropriate screening and its subsequent treatment have not been demonstrated to limit neonatal malformations to date. This study aimed to detect congenital heart diseases in newborns of mothers with GDM by evaluating the existence of a correlation with maternal glycemic control. This observational prospective study investigated newborns of mothers with GDM enrolled during a period of 9 months. Four subgroups were considered according to the type of maternal glucidic alteration during pregnancy and the home treatment: impaired glucose tolerance, insulin-dependent gestational diabetes mellitus (IDDM), non-insulin-dependent gestational diabetes mellitus (NIDDM), and gestational diabetes not controlled (NC: untreated diabetes). Student's t test was used to compare the subgroups. The study enrolled 65 newborns (30 boys) born to 82 of mothers with impaired glucidic metabolism. Patent ductus arteriosus was observed in 11 patients (16.9 %), pulmonary stenosis of mild grade in 4 patients ( 6.2 %), and hypertrophy of the ventricular septum in 22 patients (33.8 %). A total of 14 patients had increased thickness in the left ventricle posterior wall, and 17 patients had an abnormal electrocardiogram. Hyperglycemia can influence the development of the fetal heart, affecting both its structure and its function. A treatment with insulin for women with GDM is supported by the study data.

Alterations in gastrointestinal, endocrine, and metabolic processes after bariatric Roux-en-Y gastric bypass surgery

OBJECTIVE

Obesity leads to severe long-term complications and reduced life expectancy. Roux-en-Y gastric bypass (RYGB) surgery induces excessive and continuous weight loss in (morbid) obesity, although it causes several abnormal anatomical and physiological conditions.

RESEARCH DESIGN AND METHODS

To distinctively unveil effects of RYGB surgery on β-cell function and glucose turnover in skeletal muscle, liver, and gut, nondiabetic, morbidly obese patients were studied before (pre-OP, five female/one male, BMI: 49 ± 3 kg/m(2), 43 ± 2 years of age) and 7 ± 1 months after (post-OP, BMI: 37 ± 3 kg/m(2)) RYGB surgery, compared with matching obese (CON(ob), five female/one male, BMI: 34 ± 1 kg/m(2), 48 ± 3 years of age) and lean controls (CON(lean), five female/one male, BMI: 22 ± 0 kg/m(2), 42 ± 2 years of age). Oral glucose tolerance tests (OGTTs), hyperinsulinemic-isoglycemic clamp tests, and mechanistic mathematical modeling allowed determination of whole-body insulin sensitivity (M/I), OGTT and clamp test β-cell function, and gastrointestinal glucose absorption.

RESULTS

Post-OP lost (P < 0.0001) 35 ± 3 kg body weight. M/I increased after RYGB, becoming comparable to CON(ob), but remaining markedly lower than CON(lean) (P < 0.05). M/I tightly correlated (τ = -0.611, P < 0.0001) with fat mass. During OGTT, post-OP showed ≥15% reduced plasma glucose from 120 to 180 min (≤4.5 mmol/L), and 29-fold elevated active glucagon-like peptide-1 (GLP-1) dynamic areas under the curve, which tightly correlated (r = 0.837, P < 0.001) with 84% increased β-cell secretion. Insulinogenic index (0-30 min) in post-OP was ≥29% greater (P < 0.04). At fasting, post-OP showed approximately halved insulin secretion (P < 0.05 vs. pre-OP). Insulin-stimulated insulin secretion in post-OP was 52% higher than before surgery, but 1-2 pmol/min(2) lower than in CON(ob)/CON(lean) (P < 0.05). Gastrointestinal glucose absorption was comparable in pre-OP and post-OP, but 9-26% lower from 40 to 90 min in post-OP than in CON(ob)/CON(lean) (P < 0.04).

CONCLUSIONS

RYGB surgery leads to decreased plasma glucose concentrations in the third OGTT hour and exaggerated β-cell function, for which increased GLP-1 release seems responsible, whereas gastrointestinal glucose absorption remains unchanged but lower than in matching controls.