Effect of Metformin on the High-Density Lipoprotein Proteome in Youth with Type 1 Diabetes

Background: Youth with type 1 diabetes (T1D) have normal or elevated High-Density Lipoprotein Cholesterol (HDL-C), however, the function of HDL, partly mediated by the HDL proteome, may be impaired. Metformin can be used as an adjunct therapy in youth with T1D, but its effects on the HDL proteome are unknown. Objective: To determine the effect of metformin on the HDL proteome. Subjects: Youth (12-20 years old) with T1D who had a BMI \u3e 90th percentile, HbA1c \u3e 8.0% and Tanner stage 5. Methods: Double-blinded, placebo-controlled randomized sub-study. We examined the effects of metformin (n = 25) or placebo (n = 10) after 6 months on HDL proteome. Changes in HDL proteins were measured by data-independent acquisition (DIA) mass spectrometry and compared between treatment groups. As a secondary outcome, associations between proteins of interest and the most studied function of HDL, the cholesterol efflux capacity (CEC), was examined. Results: The relative abundance of 84 HDL-associated proteins were measured. Two proteins were significantly affected by metformin treatment, peptidoglycan recognition protein 2 (PGRP2; +23.4%, p = .0058) and alpha-2-macroglobulin (A2MG; +29.8%, p = .049). Metformin did not significantly affect CEC. Changes in affected HDL proteins did not correlate with CEC. Conclusions: Despite having little effect on HDL-C, metformin increased PGRP2 and A2MG protein on HDL in youth with T1D, but had no significant effect on CEC. Further studies are needed to understand the impact of PGRP2 and A2MG on other HDL functions

Review of methods for measuring β-cell function: Design considerations from the Restoring Insulin Secretion (RISE) Consortium

The Restoring Insulin Secretion (RISE) study was initiated to evaluate interventions to slow or reverse the progression of β-cell failure in type 2 diabetes (T2D). To design the RISE study, we undertook an evaluation of methods for measurement of β-cell function and changes in β-cell function in response to interventions. In the present paper, we review approaches for measurement of β-cell function, focusing on methodologic and feasibility considerations. Methodologic considerations included: (1) the utility of each technique for evaluating key aspects of β-cell function (first- and second-phase insulin secretion, maximum insulin secretion, glucose sensitivity, incretin effects) and (2) tactics for incorporating a measurement of insulin sensitivity in order to adjust insulin secretion measures for insulin sensitivity appropriately. Of particular concern were the capacity to measure β-cell function accurately in those with poor function, as is seen in established T2D, and the capacity of each method for demonstrating treatment-induced changes in β-cell function. Feasibility considerations included: staff burden, including time and required methodological expertise; participant burden, including time and number of study visits; and ease of standardizing methods across a multicentre consortium. After this evaluation, we selected a 2-day measurement procedure, combining a 3-hour 75-g oral glucose tolerance test and a 2-stage hyperglycaemic clamp procedure, augmented with arginine

Metformin Improves Peripheral Insulin Sensitivity in Youth With Type 1 Diabetes

Context: Type 1 diabetes in adolescence is characterized by insulin deficiency and insulin resistance (IR), both thought to increase cardiovascular disease risk. We previously demonstrated that adolescents with type 1 diabetes have adipose, hepatic, and muscle IR, and that metformin lowers daily insulin dose, suggesting improved IR. However, whether metformin improves IR in muscle, hepatic, or adipose tissues in type 1 diabetes was unknown. Objective: Measure peripheral, hepatic, and adipose insulin sensitivity before and after metformin or placebo therapy in youth with obesity with type 1 diabetes. Design: Double-blind, placebo-controlled clinical trial. Setting: Multi-center at eight sites of the T1D Exchange Clinic Network. Participants: A subset of 12- to 19-year-olds with type 1 diabetes (inclusion criteria: body mass index ≥85th percentile, HbA1c 7.5% to 9.9%, insulin dosing ≥0.8 U/kg/d) from a larger trial (NCT02045290) were enrolled. Intervention: Participants were randomized to 3 months of metformin (N = 19) or placebo (N = 18) and underwent a three-phase hyperinsulinemic euglycemic clamp with glucose and glycerol isotope tracers to assess tissue-specific IR before and after treatment. Main outcome measures: Peripheral insulin sensitivity, endogenous glucose release, rate of lipolysis. Results: Between-group differences in change in insulin sensitivity favored metformin regarding whole-body IR [change in glucose infusion rate 1.3 (0.1, 2.4) mg/kg/min, P = 0.03] and peripheral IR [change in metabolic clearance rate 0.923 (-0.002, 1.867) dL/kg/min, P = 0.05]. Metformin did not impact insulin suppression of endogenous glucose release (P = 0.12). Adipose IR was not assessable with traditional methods in this highly IR population. Conclusions: Metformin appears to improve whole-body and peripheral IR in youth who are overweight/obese with type 1 diabetes

Effect of Metformin Added to Insulin on Glycemic Control Among Overweight/Obese Adolescents With Type 1 Diabetes: A Randomized Clinical Trial

Importance Previous studies assessing the effect of metformin on glycemic control in adolescents with type 1 diabetes have produced inconclusive results. Objective To assess the efficacy and safety of metformin as an adjunct to insulin in treating overweight adolescents with type 1 diabetes. Design, Setting, and Participants Multicenter (26 pediatric endocrinology clinics), double-blind, placebo-controlled randomized clinical trial involving 140 adolescents aged 12.1 to 19.6 years (mean [SD] 15.3 [1.7] years) with mean type 1 diabetes duration 7.0 (3.3) years, mean body mass index (BMI) 94th (4) percentile, mean total daily insulin 1.1 (0.2) U/kg, and mean HbA1c 8.8% (0.7%). Interventions Randomization to receive metformin (n = 71) (≤2000 mg/d) or placebo (n = 69). Main Outcomes and Measures Primary outcome was change in HbA1c from baseline to 26 weeks adjusted for baseline HbA1c. Secondary outcomes included change in blinded continuous glucose monitor indices, total daily insulin, BMI, waist circumference, body composition, blood pressure, and lipids. Results Between October 2013 and February 2014, 140 participants were enrolled. Baseline HbA1c was 8.8% in each group. At 13-week follow-up, reduction in HbA1c was greater with metformin (−0.2%) than placebo (0.1%; mean difference, −0.3% [95% CI, −0.6% to 0.0%]; P = .02). However, this differential effect was not sustained at 26-week follow up when mean change in HbA1c from baseline was 0.2% in each group (mean difference, 0% [95% CI, −0.3% to 0.3%]; P = .92). At 26-week follow-up, total daily insulin per kg of body weight was reduced by at least 25% from baseline among 23% (16) of participants in the metformin group vs 1% (1) of participants in the placebo group (mean difference, 21% [95% CI, 11% to 32%]; P = .003), and 24% (17) of participants in the metformin group and 7% (5) of participants in the placebo group had a reduction in BMI z score of 10% or greater from baseline to 26 weeks (mean difference, 17% [95% CI, 5% to 29%]; P = .01). Gastrointestinal adverse events were reported by more participants in the metformin group than in the placebo group (mean difference, 36% [95% CI, 19% to 51%]; P < .001). Conclusions and Relevance Among overweight adolescents with type 1 diabetes, the addition of metformin to insulin did not improve glycemic control after 6 months. Of multiple secondary end points, findings favored metformin only for insulin dose and measures of adiposity; conversely, use of metformin resulted in an increased risk for gastrointestinal adverse events. These results do not support prescribing metformin to overweight adolescents with type 1 diabetes to improve glycemic control

OGTT Glucose Response Curves, Insulin Sensitivity, and β-Cell Function in RISE: Comparison Between Youth and Adults at Randomization and in Response to Interventions to Preserve β-Cell Function

We examined the glucose response curves (biphasic [BPh], monophasic [MPh], incessant increase [IIn]) during an oral glucose tolerance test (OGTT) and their relationship to insulin sensitivity (IS) and β-cell function (βCF) in youth versus adults with impaired glucose tolerance or recently diagnosed type 2 diabetes. RESEARCH DESIGN AND METHODS: This was both a cross-sectional and a longitudinal evaluation of participants in the RISE study randomized to metformin alone for 12 months or glargine for 3 months followed by metformin for 9 months. At baseline/randomization, OGTTs (85 youth, 353 adults) were categorized as BPh, MPh, or IIn. The relationship of the glucose response curves to hyperglycemic clamp-measured IS and βCF at baseline and the change in glucose response curves 12 months after randomization were assessed. RESULTS: At randomization, the prevalence of the BPh curve was significantly higher in youth than adults (18.8% vs. 8.2%), with no differences in MPh or IIn. IS did not differ across glucose response curves in youth or adults. However, irrespective of curve type, youth had lower IS than adults (P < 0.05). βCF was lowest in IIn versus MPh and BPh in youth and adults (P < 0.05), yet compared with adults, youth had higher βCF in BPh and MPh (P < 0.005) but not IIn. At month 12, the change in glucose response curves did not differ between youth and adults, and there was no treatment effect. CONCLUSIONS: Despite a twofold higher prevalence of the more favorable BPh curve in youth at randomization, RISE interventions did not result in beneficial changes in glucose response curves in youth compared with adults. Moreover, the typical β-cell hypersecretion in youth was not present in the IIn curve, emphasizing the severity of β-cell dysfunction in youth with this least favorable glucose response curve

Integrated plasma proteomic and single-cell immune signaling network signatures demarcate mild, moderate, and severe COVID-19

The biological determinants of the wide spectrum of COVID-19 clinical manifestations are not fully understood. Here, over 1400 plasma proteins and 2600 single-cell immune features comprising cell phenotype, basal signaling activity, and signaling responses to inflammatory ligands were assessed in peripheral blood from patients with mild, moderate, and severe COVID-19, at the time of diagnosis. Using an integrated computational approach to analyze the combined plasma and single-cell proteomic data, we identified and independently validated a multivariate model classifying COVID-19 severity (multi-class AUCtraining = 0.799, p-value = 4.2e-6; multi-class AUCvalidation = 0.773, p-value = 7.7e-6). Features of this high-dimensional model recapitulated recent COVID-19 related observations of immune perturbations, and revealed novel biological signatures of severity, including the mobilization of elements of the renin-angiotensin system and primary hemostasis, as well as dysregulation of JAK/STAT, MAPK/mTOR, and NF-κB immune signaling networks. These results provide a set of early determinants of COVID-19 severity that may point to therapeutic targets for the prevention of COVID-19 progression

Understanding diabetes heterogeneity:key steps towards precision medicine in diabetes

Diabetes is a highly heterogeneous condition; yet, it is diagnosed by measuring a single blood-borne metabolite, glucose, irrespective of aetiology. Although pragmatically helpful, disease classification can become complex and limit advances in research and medical care. Here, we describe diabetes heterogeneity, highlighting recent approaches that could facilitate management by integrating three disease models across all forms of diabetes, namely, the palette model, the threshold model and the gradient model. Once diabetes has developed, further worsening of established diabetes and the subsequent emergence of diabetes complications are kept in check by multiple processes designed to prevent or circumvent metabolic dysfunction. The impact of any given disease risk factor will vary from person-to-person depending on their background, diabetes-related propensity, and environmental exposures. Defining the consequent heterogeneity within diabetes through precision medicine, both in terms of diabetes risk and risk of complications, could improve health outcomes today and shine a light on avenues for novel therapy in the future.</p

Pregnancy outcomes in youth with type 2 diabetes: The TODAY Study Experience.

OBJECTIVE: We evaluated pregnancy outcomes, maternal and fetal/neonatal, during the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study. RESEARCH DESIGN AND METHODS: The TODAY study was a randomized controlled trial comparing three treatment options for youth with type 2 diabetes. Informed consent included the requirement for contraception, including abstinence; this was reinforced at each visit. Following informed consent, self-reported data related to the mother’s prenatal care and delivery and the infant’s health were retrospectively collected. When permitted, maternal medical records and infant birth records were reviewed. RESULTS: Of the 452 enrolled female participants, 46 (10.2%) had 63 pregnancies. Despite continued emphasis on adequate contraception, only 4.8% of the pregnant participants reported using contraception prior to pregnancy. The mean age at first pregnancy was 18.4 years; the mean diabetes duration was 3.17 years. Seven pregnancies were electively terminated; three pregnancies had no data reported. Of the remaining 53 pregnancies, 5 (9.4%) resulted in early pregnancy loss, and 7 (13%) resulted in loss with inadequate pregnancy duration data. Two pregnancies ended in stillbirth, at 27 and 37 weeks, and 39 ended with a live-born infant. Of the live-born infants, six (15.4%) were preterm and eight (20.5%) had a major congenital anomaly. CONCLUSIONS: Despite diabetes-specific information recommending birth control and the avoidance of pregnancy, 10% of the study participants became pregnant. Pregnancies in youth with type 2 diabetes may be especially prone to result in congenital anomalies. Reasons for the high rate of congenital anomalies are uncertain, but may include poor metabolic control and extreme obesity