Association of GLP-1 secretion with parameters of glycemic control in women after gestational diabetes mellitus.

INTRODUCTION: Women with a history of gestational diabetes mellitus (GDM) are at high risk of developing type 2 diabetes, while the exact mechanisms underlying its pathophysiology are still unclear. We investigated the association of glucagon-like peptide-1 (GLP-1) response to oral glucose with parameters of glycemic control in women with previous GDM in the prospective PPSDiab (Prediction, Prevention, and Subclassification of Type 2 Diabetes) study. RESEARCH DESIGN AND METHODS: Glucose metabolism parameters and GLP-1 secretion were analyzed during oral glucose tolerance test (OGTT) in women with previous GDM (n=129) and women with a history of normal glucose tolerance (n=67) during pregnancy (controls). First- and second-phase insulin and GLP-1 secretion in relation to plasma glucose (PG) levels were assessed, and development of pre-diabetes was analyzed after 5-year follow-up among women with previous GDM and a normal glycemic state at baseline (n=58). RESULTS: The area under the curve (AUC during the OGTT 0-120 min) of PG and insulin but not GLP-1 differed significantly between post-GDM women and controls. However, women with previous GDM had a significantly decreased GLP-1 response in relation to PG and plasma insulin during the second phase of the OGTT. After a follow-up of 5 years, 19.0% post-GDM women with a normal glycemic state at the baseline visit developed abnormal glucose metabolism. The total, first- and second-phase AUC GLP-1/PG and GLP-1/insulin ratios were not associated with development of abnormal glucose tolerance. CONCLUSIONS: Women with previous GDM showed a reduced GLP-1 response in relation to PG and insulin concentrations indicating early abnormalities in glucose metabolism. However, the altered GLP-1 response to oral glucose did not predict progression to pre-diabetes and type 2 diabetes in the first 5 years after GDM.

Mechanisms of weight loss-induced remission in people with prediabetes: a post-hoc analysis of the randomised, controlled, multicentre Prediabetes Lifestyle Intervention Study (PLIS).

BACKGROUND: Remission of type 2 diabetes can occur as a result of weight loss and is characterised by liver fat and pancreas fat reduction and recovered insulin secretion. In this analysis, we aimed to investigate the mechanisms of weight loss- induced remission in people with prediabetes. METHODS: In this prespecified post-hoc analysis, weight loss-induced resolution of prediabetes in the randomised, controlled, multicentre Prediabetes Lifestyle Intervention Study (PLIS) was assessed, and the results were validated against participants from the Diabetes Prevention Program (DPP) study. For PLIS, between March 1, 2012, and Aug 31, 2016, participants were recruited from eight clinical study centres (including seven university hospitals) in Germany and randomly assigned to receive either a control intervention, a standard lifestyle intervention (ie, DPP-based intervention), or an intensified lifestyle intervention for 12 months. For DPP, participants were recruited from 23 clinical study centres in the USA between July 31, 1996, and May 18, 1999, and randomly assigned to receive either a standard lifestyle intervention, metformin, or placebo. In both PLIS and DPP, only participants who were randomly assigned to receive lifestyle intervention or placebo and who lost at least 5% of their bodyweight were included in this analysis. Responders were defined as people who returned to normal fasting plasma glucose (FPG; <5·6 mmol/L), normal glucose tolerance (<7·8 mmol/L), and HbA1c less than 39 mmol/mol after 12 months of lifestyle intervention or placebo or control intervention. Non-responders were defined as people who had FPG, 2 h glucose, or HbA1c more than these thresholds. The main outcomes for this analysis were insulin sensitivity, insulin secretion, visceral adipose tissue (VAT), and intrahepatic lipid content (IHL) and were evaluated via linear mixed models. FINDINGS: Of 1160 participants recruited to PLIS, 298 (25·7%) had weight loss of 5% or more of their bodyweight at baseline. 128 (43%) of 298 participants were responders and 170 (57%) were non-responders. Responders were younger than non-responders (mean age 55·6 years [SD 9·9] vs 60·4 years [8·6]; p<0·0001). The DPP validation cohort included 683 participants who lost at least 5% of their bodyweight at baseline. Of these, 132 (19%) were responders and 551 (81%) were non-responders. In PLIS, BMI reduction was similar between responders and non-responders (responders mean at baseline 32·4 kg/m2 [SD 5·6] to mean at 12 months 29·0 kg/m2 [4·9] vs non-responders 32·1 kg/m2 [5·9] to 29·2 kg/m2 [5·4]; p=0·86). However, whole-body insulin sensitivity increased more in responders than in non-responders (mean at baseline 291 mL/[min × m2], SD 60 to mean at 12 months 378 mL/[min × m2], 56 vs 278 mL/[min × m2], 62, to 323 mL/[min × m2], 66; p<0·0001), whereas insulin secretion did not differ within groups over time or between groups (responders mean at baseline 175 pmol/mmol [SD 64] to mean at 12 months 163·7 pmol/mmol [60·6] vs non-responders 158·0 pmol/mmol [55·6] to 154·1 pmol/mmol [56·2]; p=0·46). IHL decreased in both groups, without a difference between groups (responders mean at baseline 10·1% [SD 8·7] to mean at 12 months 3·5% [3·9] vs non-responders 10·3% [8·1] to 4·2% [4·2]; p=0·34); however, VAT decreased more in responders than in non-responders (mean at baseline 6·2 L [SD 2·9] to mean at 12 months 4·1 L [2·3] vs 5·7 L [2·3] to 4·5 L [2·2]; p=0·0003). Responders had a 73% lower risk of developing type 2 diabetes than non-responders in the 2 years after the intervention ended. INTERPRETATION: By contrast to remission of type 2 diabetes, resolution of prediabetes was characterised by an improvement in insulin sensitivity and reduced VAT. Because return to normal glucose regulation (NGR) prevents development of type 2 diabetes, we propose the concept of remission of prediabetes in analogy to type 2 diabetes. We suggest that remission of prediabetes should be the primary therapeutic aim in individuals with prediabetes. FUNDING: German Federal Ministry for Education and Research via the German Center for Diabetes Research; the Ministry of Science, Research and the Arts Baden-Württemberg; the Helmholtz Association and Helmholtz Munich; the Cluster of Excellence Controlling Microbes to Fight Infections; and the German Research Foundation.

Moderate dietary salt restriction improves blood pressure and mental well-being in patients with primary aldosteronism: The salt CONNtrol trial.

BACKGROUND: Primary aldosteronism (PA) is a frequent cause of hypertension. Aldosterone excess together with high dietary salt intake aggravates cardiovascular damage, despite guideline-recommended mineralocorticoid receptor antagonist (MRA) treatment. OBJECTIVES: To investigate the antihypertensive impact of a moderate dietary salt restriction and associated physiological changes, including mental well-being. METHODS: A total of 41 patients with PA on a stable antihypertensive regimen-including MRA-followed a dietary salt restriction for 12 weeks with structured nutritional training and consolidation by a mobile health app. Salt intake and adherence were monitored every 4 weeks using 24-h urinary sodium excretion and nutrition protocols. Body composition was assessed by bioimpedance analysis and mental well-being by validated questionnaires. RESULTS: Dietary salt intake significantly decreased from 9.1 to 5.2 g/d at the end of the study. In parallel, systolic (130 vs. 121 mm Hg) and diastolic blood pressure (BP) (84 vs. 81 mm Hg) improved significantly. Patients' aptitude of estimating dietary salt content was refined significantly (underestimation by 2.4 vs. 1.4 g/d). Salt restriction entailed a significant weight loss of 1.4 kg, improvement in pulse pressure (46 vs. 40 mm Hg) and normalization of depressive symptoms (PHQD scale, p < 0.05). Salt restriction, cortisol after dexamethasone suppression test and dosage of renin-angiotensin-aldosterone-system (RAAS) blockers were independently associated with BP reduction. CONCLUSION: A moderate restriction of dietary salt intake in patients with PA substantially reduces BP and depressive symptoms. Moreover, the findings underline that a sufficient RAAS blockade seems to augment the effects of salt restriction on BP and cardiovascular risk.

Associations of gestational diabetes and proton density fat fraction of vertebral bone marrow and paraspinal musculature in premenopausal women.

Background and objective: Fat content in bones and muscles, quantified by magnetic resonance imaging (MRI) as a proton density fat fraction (PDFF) value, is an emerging non-invasive biomarker. PDFF has been proposed to indicate bone and metabolic health among postmenopausal women. Premenopausal women with a history of gestational diabetes (GDM) carry an increased risk of developing type 2 diabetes and an increased risk of fractures. However, no studies have investigated the associations between a history of GDM and PDFF of bone or of paraspinal musculature (PSM), composed of autochthonous muscle (AM) and psoas muscle, which are responsible for moving and stabilizing the spine. This study aims to investigate whether PDFF of vertebral bone marrow and of PSM are associated with a history of GDM in premenopausal women. Methods: A total of 37 women (mean age 36.3 ± 3.8 years) who were 6 to 15 months postpartum with (n=19) and without (n=18) a history of GDM underwent whole-body 3T MRI, including a chemical shift encoding-based water-fat separation. The PDFF maps were calculated for the vertebral bodies and PSM. The cross-sectional area (CSA) of PSM was obtained. Associations between a history of GDM and PDFF were assessed using multivariable linear and logistic regression models. Results: The PDFF of the vertebral bodies was significantly higher in women with a history of GDM (GDM group) than in women without (thoracic: median 41.55 (interquartile range 32.21-49.48)% vs. 31.75 (30.03-34.97)%; p=0.02, lumbar: 47.84 (39.19-57.58)% vs. 36.93 (33.36-41.31)%; p=0.02). The results remained significant after adjustment for age and body mass index (BMI) (p=0.01-0.02). The receiver operating characteristic curves showed optimal thoracic and lumbar vertebral PDFF cutoffs at 38.10% and 44.18%, respectively, to differentiate GDM (AUC 0.72 and 0.73, respectively, sensitivity 0.58, specificity 0.89). The PDFF of the AM was significantly higher in the GDM group (12.99 (12.18-15.90)% vs. 10.83 (9.39-14.71)%; p=0.04) without adjustments, while the CSA was similar between the groups (p=0.34). Conclusion: A history of GDM is significantly associated with a higher PDFF of the vertebral bone marrow, independent of age and BMI. This statistical association between GDM and increased PDFF highlights vertebral bone marrow PDFF as a potential biomarker for the assessment of bone health in premenopausal women at risk of diabetes.

A Normalized Real-Life Glucose Profile After Diet-Induced Remission of Type 2 Diabetes: A Pilot Trial.

Background/objective Type 2 diabetes related to metabolic syndrome is often partially reversible after weight loss. We conducted a pilot trial on whether complete remission to the point of a normalized real-life glucose profile, measured by continuous subcutaneous monitoring, can be achieved. Methods We conducted a mono-center, single-arm intervention trial between January 20, 2020, and January 12, 2021, in Munich, Germany. Ten participants had type 2 diabetes related to metabolic syndrome for a maximum of six years. They received a six-month lifestyle intervention including up to three months of a very-low-calorie formula diet, followed by stepwise food reintroduction and regular behavioral lifestyle counseling. The primary outcome was the status of glucose control at the end of the intervention. Complete remission was defined as normalization of the real-life glucose profile without glucose-lowering medication over at least five days. We measured anthropometric and biochemical parameters, body fat distribution by MRI, and insulin secretory reserve by an arginine stimulation test. Results Seven participants completed the trial, one reached complete remission, three achieved partial remission, and three displayed improved glucose control still in the diabetic range. A reduction of median glycosylated hemoglobin by -10 mmol/mol (-22.0 to -5.0; p = 0.016) co-occurred with weight loss of -6.4 kg (-14.2 to -3.5; p = 0.031). The insulin secretory reserve remained unchanged. Conclusions Complete remission of type 2 diabetes related to metabolic syndrome to the point of a normalized real-life glucose profile is possible through lifestyle intervention. Full intervention success remains challenging even with intensive counseling and support.

Altered Circulating Leptin, hGH, and IGF-I in Prediabetes and Screening-Diagnosed T2DM Unrelated to Metabolic Syndrome in Women Post Gestational Diabetes.

Recently, we proposed two pathophysiologic subtypes of type 2 diabetes mellitus (T2DM), one related and one unrelated to metabolic syndrome. To begin to understand the pathophysiology of the subtype unrelated to metabolic syndrome, we now measured selected hormones and signaling molecules in affected individuals. In this cross-sectional analysis, we examined 138 women out of the monocenter, post gestational diabetes study PPSDiab. Of these women, 73 had prediabetes or screening-diagnosed T2DM, 40 related to metabolic syndrome and 33 unrelated. The remaining 65 women were normoglycemic controls. Our analysis included medical history, anthropometrics, oral glucose tolerance testing, laboratory chemistry, and cardiopulmonary exercise testing. In addition, plasma proinsulin/insulin ratio, growth hormone (hGH) nadir during oral glucose tolerance testing, Insulin-like Growth Factor I (IGF-I), Leptin, Resistin, Adiponectin, Fetuin-a, FGF21, and myostatin were measured. Compared to controls, women with prediabetes or screening-diagnosed T2DM unrelated to metabolic syndrome depicted higher plasma Leptin [10.47(6.6-14.57) vs. 5.52(3.15-10.02); p<0.0001] and IGF-I [193.01(171.00-213.30) vs. 167.97(138.77-200.64); p=0.0008], as well as a lower hGH nadir [0.07(0.05-0.15) vs. 0.14(0.08-0.22; p<0.0001]. These differences were independent of body adiposity. Women with prediabetes or T2DM related to metabolic syndrome, in comparison to controls, displayed elevated Leptin, Fetuin-a, and FGF21, as well as reduced Adiponectin and hGH nadir. Based on our study, altered Leptin and hGH/IGF-I signaling could potentially contribute to the pathophysiology of prediabetes and T2DM unrelated to metabolic syndrome. Further mechanistic investigations of these signaling pathways in the context of lean T2DM are necessary to test causal relationships.

A novel smartphone app to change risk behaviors of women after gestational diabetes: A randomized controlled trial.

AIMS: Women after gestational diabetes mellitus (GDM) are a risk group for cardiometabolic diseases but are hard to reach by conventional lifestyle programs. Therefore, we tested whether a novel, smartphone-delivered intervention, TRIANGLE, is accepted by women after GDM and alters cardiometabolic risk behaviors and outcomes. TRIANGLE targets gradual habit change of mind and emotion, physical activity, nutrition, and sleep. METHODS: We conducted a 6-month multicenter, randomized-controlled trial of TRIANGLE versus standard care with 66 women 3-18 months after GDM in Germany. The primary outcome was the proportion of women achieving ≥3 out of 5 Diabetes Prevention Program goals, i.e. physical activity ≥150 min/week (moderate to high intensity), fiber intake ≥15 g/1,000 kcal, fat intake <30% of total energy intake, saturated fat intake <10% of total energy intake, and weight reduction ≥5% if BMI ≥23 kg/m2 or weight maintenance if BMI <23 kg/m2. Intervention participants also rated the TRIANGLE app in the Mobile Application Rating Scale (uMARS). RESULTS: In the predefined, modified intention-to-treat analysis including 64 women, 6 out of 27 women in the intervention group [22%(10-40)] and 3 out of 27 women in the control group [11%(3-27)] reached the primary outcome (p = 0.47). In the predefined per-protocol intervention subgroup, the proportion was 4 out of 14 women [29%(11-55); p = 0.20 vs. control]. TRIANGLE app users were active on 42% of days and rated the app's quality and perceived impact with 4.3±0.8 out of 5 uMARS points. CONCLUSIONS: This first trial did not show the efficacy of the TRIANGLE intervention. However, the app was well accepted and considered helpful by most users. Therefore, this trial supports further development and testing of TRIANGLE and other app interventions for women after GDM. Additionally, it identifies necessary adaptations in trial design to better accommodate non-intensive lifestyle interventions for this target group. TRIAL REGISTRATION: Trial registration at drks.de (DRKS00012996).

Function outperforms morphology in the assessment of muscular contribution to insulin sensitivity in premenopausal women.

INTRODUCTION: Skeletal muscle contributes significantly to insulin sensitivity in humans. However, which non-invasive measurement best reflects this contribution remains unknown. Consequently, this paper compares morphologic and functional measurements. RESEARCH METHODS AND DESIGN: We conducted a cross-sectional analysis of 144 premenopausal women enrolled in the "Prediction, Prevention, and Sub-classification of Type 2 Diabetes" (PPSDiab) cohort study. For the analysis, we quantified insulin sensitivity by oral glucose tolerance testing and, in a subgroup of 30 women, euglycemic clamp. To assess skeletal muscle, we measured volume by magnetic resonance imaging, intramyocellular lipid content by magnetic resonance spectroscopy, and physical fitness by cardiopulmonary exercise testing. RESULTS: The mean age of the cohort was 35.7 ± 4.1 years and 94 participants (65%) had a history of gestational diabetes mellitus. Of the morphologic and functional muscle parameters, the maximum workload achieved during cardiopulmonary exercise testing associated most closely with insulin sensitivity (standardized beta = 0.39; p < .001). Peak oxygen uptake also demonstrated significant associations, whereas muscle volume and intramyocellular lipid content displayed none. CONCLUSION: Functional measurements provided a better assessment of the muscular contribution to insulin sensitivity than morphologic measurements in premenopausal women. In particular, exercise testing rendered an easy and cost-effective method applicable in clinical settings and other human studies.

Pre-diabetes, diabetes and fluctuations of glucose tolerance after gestational diabetes mellitus: 5-year follow-up of a contemporary, prospective study in Germany.

INTRODUCTION: Ten years ago, Germany started offering screening for gestational diabetes mellitus (GDM) to all pregnant women. This approach revealed more but also, on average, less severe cases of GDM than the risk-based screening practiced previously. We now examined the incidence of pre-diabetes and diabetes following a GDM diagnosis in the era of universal screening in Germany and compared our results with studies in the previous period. Additionally, we examined the year-to-year fluctuations of glucose tolerance after a pregnancy complicated by GDM. RESEARCH DESIGN AND METHODS: We report 5-year follow-up data from 202 women in the prospective, monocenter, postpartum study PPSDiab. Consecutive recruitment took place in Munich, Germany between 2011 and 2016. In the study, we conducted yearly examinations that included anthropometrics, laboratory chemistry and oral glucose tolerance testing. RESULTS: During the first 5 years post partum, 111 (55%) and 12 (6%) of the women developed pre-diabetes and type 2 diabetes, respectively, while 2 (1%) developed type 1 diabetes. Impaired fasting glucose (IFG) was the most common first manifestation of disturbed glucose tolerance, followed by impaired glucose tolerance (IGT), the combination of IFG and IGT, and diabetes. Glucose tolerance did not deteriorate steadily in most women but fluctuated from year to year. CONCLUSIONS: In our analysis, the incidence of diabetes, both type 1 and type 2, after GDM diagnosed in universal screening was substantially lower than in studies from the previous period of risk-based screening. Nevertheless, the high incidence of pre-diabetes we observed after GDM still confirms the importance of this diagnosis as a risk marker. Additionally, we documented frequent fluctuations of glucose tolerance from 1 year to the next. Therefore, a single postpartum glucose tolerance test, as currently practiced in routine care, may be insufficient for reliable risk stratification after GDM.

No association of natural killer cell number and function in peripheral blood with overweight/obesity and metabolic syndrome in a cohort of young women.

AIM: To reexamine the associations of NK cell number and function in the peripheral blood with overweight/obesity and the metabolic syndrome in a large, well-phenotyped human cohort. METHODS: Cross-sectional analysis of 273 women in the PPSDiab Study; measurement of absolute and relative number of NK cells in peripheral blood, and of functional parameters CD69 positivity and cytotoxicity against K562 cells; group comparison of NK cell characteristics between lean, overweight, and obese participants, as well as metabolic syndrome scores of 0, 1, 2, and ≥3; Spearman correlation analyses to clinical parameters related to the metabolic syndrome. RESULTS: We found no differences in NK cell number and function between lean, overweight, and obese women (relative NK cell number (median (Q1-Q3), [%]) 5.1(2.6-9.4) vs. 4.8 (2.9-8.4) vs. 3.8 (1.7-7.8), p = 0.187; absolute NK cell number [106 /L]: 86.9 (44.6-188.8) vs. 92.6 (52.5-154.6) vs. 85.9 (44-153.8), p = 0.632; CD69+ [%]: 27.2 (12.9-44.3) vs. 37.6 (13.2-52.8) vs. 33.6 (16.3-45), p = 0.136; cytotoxicity [%]: 11.0 (7.1-14.5) vs. 8.5 (6.4-13.2) vs. 11.3 (8.7-14.2), p = 0.094), as well as between different metabolic syndrome scores. Nonesterified fatty acids correlated with absolute and relative NK cell number and cytotoxicity (ρ [p-value]: 0.142 [0.021], 0.119 [0.049], and 0.131 [0.035], respectively). Relative NK cell number further correlated with high-density lipoprotein cholesterol (0.144 [0.018]) and cytotoxicity with 2 h glucose in oral glucose tolerance testing (0.132 [0.034]). CD69 positivity correlated with body fat (0.141 [0.021]), triglycerides (0.129 [0.033]), and plasma leptin (0.155 [0.010]). After correction for multiple testing, none of the associations remained significant. CONCLUSION: In the present study, we observed no associations of NK cell number and function in the peripheral blood with overweight/obesity and the metabolic syndrome. Extreme phenotypes of obesity and the metabolic syndrome might have caused differing results in previous studies. Further analyses with a focus on compartments other than peripheral blood may help to clarify the relation between NK cells and metabolic diseases.

Associations of endogenous androgens and sex hormone-binding globulin with kidney function and chronic kidney disease.

Introduction: The role of endogenous androgens in kidney function and disease has not been extensively explored in men and women. Research design and methods: We analyzed data from the observational KORA F4 study and its follow-up examination KORA FF4 (median follow-up time 6.5 years) including 1293 men and 650 peri- and postmenopausal women, not using exogenous sex hormones. We examined the associations between endogenous androgens (testosterone [T], dihydrotestosterone [DHT], free T [fT], free DHT [fDHT], and T/DHT), with estimated glomerular filtration rate (eGFR) at baseline and follow-up, prevalent, and incident chronic kidney disease (CKD) adjusting for common CKD risk factors. Results: At baseline, 73 men (5.7%) and 54 women (8.4%) had prevalent CKD. Cross-sectionally, no significant associations between androgens and kidney function were observed among men. In women, elevated T (ß=-1.305, [95% CI -2.290; -0.320]) and fT (ß=-1.423, [95% CI -2.449; -0.397]) were associated with lower eGFR. Prospectively, 81 men (8.8%) and 60 women (15.2%) developed incident CKD. In women, a reverse J-shaped associations was observed between DHT and incident CKD (Pnon-linear=0.029), while higher fDHT was associated with lower incident CKD risk (odds ratio per 1 standard deviation=0.613, [95% CI 0.369; 0.971]. Among men, T/DHT (ß=-0.819, [95% CI -1.413; -0.226]) and SHBG (Pnon-linear=0.011) were associated with eGFR at follow-up but not with incident CKD. Some associations appeared to be modified by type 2 diabetes (T2D). Conclusion: Suggestive associations are observed of androgens and SHBG with kidney impairment among men and women. However, larger well-phenotyped prospective studies are required to further elucidate the potential of androgens, SHBG, and T2D as modifiable risk factors for kidney function and CKD.

Association of Serum Myostatin with Body Weight, Visceral Fat Volume, and High Sensitivity C-Reactive Protein But Not With Muscle Mass and Physical Fitness in Premenopausal Women.

BACKGROUND: The myokine myostatin regulates muscle mass and has been linked to insulin resistance and metabolic syndrome. However, data on its role in humans is still limited. We, therefore, investigated the associations of serum myostatin with muscle mass, physical fitness, and components of the metabolic syndrome in a cohort of premenopausal women. METHODS: We undertook a cross-sectional analysis of 233 women from the monocenter study PPSDiab, conducted in Munich, Germany. Participants had recently completed a pregnancy with or without gestational diabetes. Our analysis included medical history, anthropometrics, oral glucose tolerance testing, laboratory chemistry, cardiopulmonary exercise testing, and magnetic resonance imaging (n=142) of visceral fat volume, left quadriceps muscle mass, and muscle fat content. Serum myostatin was quantified by a competitive enzyme-linked immunosorbent assay. RESULTS: We observed positive correlations of serum myostatin with body mass index (ρ=0.235; p=0.0003), body fat percentage (ρ=0.166; p=0.011), waist circumference (ρ=0.206; p=0.002), intraabdominal fat volume (ρ=0.182; p=0.030) and high-sensitivity C-reactive protein (ρ=0.175; p=0.008). These correlations were reproduced in linear regression analyses with adjustment for age and time after delivery. We saw no correlations with muscle mass, physical fitness, insulin sensitivity, triglycerides, HDL cholesterol, and blood pressure. CONCLUSIONS: Our observation of elevated serum myostatin in women with a higher body fat percentage, visceral obesity, and elevated c-reactive protein suggests that this myokine contributes to the altered muscle-adipose tissue crosstalk in metabolic syndrome. Elevated myostatin may advance this pathophysiologic process and could also impair the efficacy of exercise interventions. Further mechanistic studies, therefore, seem warranted.

Elucidating the formation and active state of Cu co-catalysts for photocatalytic hydrogen evolution.

The design of active and selective co-catalysts constitutes one of the major challenges in developing heterogeneous photocatalysts for energy conversion applications. This work provides a comprehensive insight into thermally induced bottom-up generation and transformation of a series of promising Cu-based co-catalysts. We demonstrate that the volcano-type HER profile as a function of calcination temperature is independent of the type of the Cu precursor but is affected by changes in oxidation state and location of the copper species. Supported by DFT modeling, our data suggest that low temperature (<200 °C) treatments facilitate electronic communication between the Cu species and TiO2, which allows for a more efficient charge utilization and maximum HER rates. In contrast, higher temperatures (>200 °C) do not affect the Cu oxidation state, but induce a gradual, temperature-dependent surface-to-bulk diffusion of Cu, which results in interstitial, tetra-coordinated Cu+ species. The disappearance of Cu from the surface and the introduction of new defect states is associated with a drop in HER performance. This work examines electronic and structural effects that are in control of the photocatalytic activity and can be transferred to other systems for further advancing photocatalysis.

Different Effects of Lifestyle Intervention in High- and Low-Risk Prediabetes: Results of the Randomized Controlled Prediabetes Lifestyle Intervention Study (PLIS).

Lifestyle intervention (LI) can prevent type 2 diabetes, but response to LI varies depending on risk subphenotypes. We tested whether individuals with prediabetes with low risk (LR) benefit from conventional LI and individuals with high risk (HR) benefit from an intensification of LI in a multicenter randomized controlled intervention over 12 months with 2 years' follow-up. A total of 1,105 individuals with prediabetes based on American Diabetes Association glucose criteria were stratified into an HR or LR phenotype based on previously described thresholds of insulin secretion, insulin sensitivity, and liver fat content. LR individuals were randomly assigned to conventional LI according to the Diabetes Prevention Program (DPP) protocol or control (1:1) and HR individuals to conventional or intensified LI with doubling of required exercise (1:1). A total of 908 (82%) participants completed the study. In HR individuals, the difference between conventional and intensified LI in postchallenge glucose change was -0.29 mmol/L [95% CI -0.54; -0.04], P = 0.025. Liver fat (-1.34 percentage points [95% CI -2.17; -0.50], P = 0.002) and cardiovascular risk (-1.82 percentage points [95% CI -3.13; -0.50], P = 0.007) underwent larger reductions with intensified than with conventional LI. During a follow-up of 3 years, intensified compared with conventional LI had a higher probability of normalizing glucose tolerance (P = 0.008). In conclusion, it is possible in HR individuals with prediabetes to improve glycemic and cardiometabolic outcomes by intensification of LI. Individualized, risk phenotype-based LI may be beneficial for the prevention of diabetes.

Serum uromodulin is inversely associated with biomarkers of subclinical inflammation in the population-based KORA F4 study.

BACKGROUND: Uromodulin is a kidney-specific glycoprotein synthesized in tubular cells of Henle's loop exerting nephroprotective and immunomodulatory functions in the urinary tract. A small amount of uromodulin is also released into the systemic circulation, where its physiological role is unknown. Serum uromodulin (sUmod) has been associated with metabolic risk factors and with cardiovascular events and mortality, where these associations were partly stronger in men than in women. In this study, we investigated the associations of sUmod with biomarkers of subclinical inflammation in a population-based sample of women and men. METHODS: Associations of sUmod with 10 biomarkers of subclinical inflammation were assessed in 1065 participants of the Cooperative Health Research in the Region of Augsburg (KORA) F4 study aged 62-81 years using linear regression models adjusted for sex, age, body mass index, estimated glomerular filtration rate and diabetes. Analyses were performed in the total study sample and stratified by sex. RESULTS: sUmod was inversely associated with white blood cell count, high-sensitive C-reactive protein, interleukin (IL)-6, tumour necrosis factor-α, myeloperoxidase, superoxide dismutase-3, IL-1 receptor antagonist and IL-22 after multivariable adjustment and correction for multiple testing (P < 0.001 for each observation). There was a trend towards a stronger association of sUmod with pro-inflammatory markers in men than in women, with a significant P for sex interaction (<0.001) regarding the relation of sUmod with IL-6. CONCLUSIONS: sUmod was inversely associated with biomarkers of subclinical inflammation in older participants of the KORA F4 study. The association of sUmod with IL-6 differed between women and men. Future research should focus on whether the immunomodulatory properties of sUmod are one explanation for the association of sUmod with cardiovascular outcomes and mortality.

A Smartphone App (TRIANGLE) to Change Cardiometabolic Risk Behaviors in Women Following Gestational Diabetes Mellitus: Intervention Mapping Approach.

BACKGROUND: Gestational diabetes mellitus (GDM) is the most common complication during pregnancy and is associated with an increased risk for the development of cardiometabolic diseases. Behavioral interventions can reduce this risk, but current solutions insufficiently address the requirements for such a program. The systematic development of a scalable mobile health (mHealth) promotion program for mothers during the first years post-GDM may contribute to solving this problem. OBJECTIVE: The aim of this project was to systematically plan and develop a theory- and evidence-based mHealth intervention to change cardiometabolic risk behaviors in women during the first 5 years post-GDM that meets women's expected standards of commercial health apps. METHODS: The intervention mapping steps 1 to 4 structured the systematic planning and development of the mHealth program described in this paper. Steps 1 and 2 led to a theory- and evidence-based logic model of change for cardiometabolic health. Based on this model, the prevention program was designed (step 3) and produced (step 4) in cooperation with industrial partners to ensure a high technological standard of the resulting smartphone app for the iPhone (Apple Inc). Step 4 included a user study with women during the first 5 years post-GDM once a beta version of the app ("TRIANGLE") was available. The user study comprised 2 test rounds of 1 week (n=5) and 4 weeks (n=6), respectively. The tests included validated questionnaires on user acceptance, user logs, and think-alouds with semistructured interviews. RESULTS: The novel TRIANGLE app is among the first self-paced smartphone apps for individual habit change in the 3 lifestyle areas of physical activity, nutrition, and psychosocial well-being. The 3 core features-a challenge system, human coaching, and a library-address 11 behavioral determinants with 39 behavior change methods to support lifestyle changes. Participants in the user study showed a high acceptance, high perceived quality, and high perceived impact of the TRIANGLE app on their health behaviors. Participants tested the app regularly, used it intuitively, and suggested improvements. We then adapted the TRIANGLE app according to the insights from the user study before the full TRIANGLE program production. CONCLUSIONS: The intervention mapping approach was feasible to plan and develop an innovative and scalable smartphone solution for women during the first 5 years post-GDM. The resulting TRIANGLE intervention has the potential to support behavior change for cardiometabolic disease prevention. However, the app needs further refinement and testing in clinical trials. Intervention mapping steps 5 (implementation plan) and 6 (evaluation plan) may support the integration of the TRIANGLE intervention into routine care. TRIAL REGISTRATION: German Clinical Trials Register DRKS00012736; https://www.drks.de/DRKS00012736.

Interaction of Full-Length Glycosylphosphatidylinositol-Anchored Proteins with Serum Proteins and Their Translocation to Cells In Vitro Depend on the (Pre-)Diabetic State in Rats and Humans.

Glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs), which are anchored at the surface of mammalian cultured and tissue cells through a carboxy-terminal GPI glycolipid, are susceptible to release into incubation medium and (rat and human) blood, respectively, in response to metabolic stress and ageing. Those GPI-APs with the complete GPI still attached form micelle-like complexes together with (lyso)phospholipids and cholesterol and are prone to degradation by serum GPI-specific phospholipase D (GPLD1), as well as translocation to the surface of acceptor cells in vitro. In this study, the interaction of GPI-APs with GPLD1 or other serum proteins derived from metabolically deranged rat and humans and their translocation were measured by microfluidic chip- and surface acoustic wave-based sensing of micelle-like complexes reconstituted with model GPI-APs. The effect of GPI-AP translocation on the integrity of the acceptor cell surface was studied as lactate dehydrogenase release. For both rats and humans, the dependence of serum GPLD1 activity on the hyperglycemic/hyperinsulinemic state was found to be primarily based on upregulation of the interaction of GPLD1 with micelle-like GPI-AP complexes, rather than on its amount. In addition to GPLD1, other serum proteins were found to interact with the GPI phosphoinositolglycan of full-length GPI-APs. Upon incubation of rat adipocytes with full-length GPI-APs, their translocation from the micelle-like complexes (and also with lower efficacy from reconstituted high-density lipoproteins and liposomes) to acceptor cells was observed, accompanied by upregulation of their lysis. Both GPI-AP translocation and adipocyte lysis became reduced in the presence of serum proteins, including (inhibited) GPLD1. The reduction was higher with serum from hyperglycemic/hyperinsulinemic rats and diabetic humans compared to healthy ones. These findings suggest that the deleterious effects of full-length GPI-APs following spontaneous release into the circulation of metabolically deranged rats and humans are counterbalanced by upregulated interaction of their GPI anchor with GPLD1 and other serum proteins. Thereby, translocation of GPI-APs to blood and tissue cells and their lysis are prevented. The identification of GPI-APs and serum proteins interacting within micelle-like complexes may facilitate the prediction and stratification of diseases that are associated with impaired cell-surface anchorage of GPI-APs, such as obesity and diabetes.