Initial Insights into the Genetic Variation Associated with Metformin Treatment Failure in Youth with Type 2 Diabetes.

Metformin is the first-line treatment for type 2 diabetes (T2D) in youth but with limited sustained glycemic response. To identify common variants associated with metformin response, we used a genome-wide approach in 506 youth from the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study and examined the relationship between T2D partitioned polygenic scores (pPS), glycemic traits, and metformin response in these youth. Several variants met a suggestive threshold (P < 1 × 10-6), though none including published adult variants reached genome-wide significance. We pursued replication of top nine variants in three cohorts, and rs76195229 in ATRNL1 was associated with worse metformin response in the Metformin Genetics Consortium (n = 7,812), though statistically not being significant after Bonferroni correction (P = 0.06). A higher ß-cell pPS was associated with a lower insulinogenic index (P = 0.02) and C-peptide (P = 0.047) at baseline and higher pPS related to two insulin resistance processes were associated with increased C-peptide at baseline (P = 0.04,0.02). Although pPS were not associated with changes in glycemic traits or metformin response, our results indicate a trend in the association of the ß-cell pPS with reduced ß-cell function over time. Our data show initial evidence for genetic variation associated with metformin response in youth with T2D.

Trajectories of eGFR and risk of albuminuria in youth with type 2 diabetes: results from the TODAY cohort study.

BACKGROUND: We conducted exploratory analyses to identify distinct trajectories of estimated glomerular filtration rate (eGFR) and their relationship with hyperfiltration, subsequent rapid eGFR decline, and albuminuria in participants with youth-onset type 2 diabetes enrolled in the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study. METHODS: Annual serum creatinine, cystatin C, urine albumin, and creatinine measurements were obtained from 377 participants followed for ≥ 10 years. Albuminuria and eGFR were calculated. Hyperfiltration peak is the greatest eGFR inflection point during follow-up. Latent class modeling was applied to identify distinct eGFR trajectories. RESULTS: At baseline, participants' mean age was 14 years, type 2 diabetes duration was 6 months, mean HbA1c was 6%, and mean eGFR was 120 ml/min/1.73 m2. Five eGFR trajectories associated with different rates of albuminuria were identified, including a "progressive increasing eGFR" group (10%), three "stable eGFR" groups with varying starting mean eGFR, and an "eGFR steady decline" group (1%). Participants who exhibited the greatest peak eGFR also had the highest levels of elevated albuminuria at year 10. This group membership was characterized by a greater proportion of female and Hispanic participants. CONCLUSIONS: Distinct eGFR trajectories that associate with albuminuria risk were identified, with the eGFR trajectory characterized by increasing eGFR over time associating with the highest level of albuminuria. These descriptive data support the current recommendations to estimate GFR annually in young persons with type 2 diabetes and provide insight into eGFR-related factors which may contribute to predictive risk strategies for kidney disease therapies in youth with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00081328, date registered 2002. A higher resolution version of the Graphical abstract is available as Supplementary information.

Metformin improves blood glucose by increasing incretins independent of changes in gluconeogenesis in youth with type 2 diabetes.

AIMS/HYPOTHESIS: Metformin is the only approved oral agent for youth with type 2 diabetes but its mechanism of action remains controversial. Recent data in adults suggest a primary role for the enteroinsular pathway, but there are no data in youth, in whom metformin efficacy is only ~50%. Our objectives were to compare incretin concentrations and rates of glucose production and gluconeogenesis in youth with type 2 diabetes before and after short-term metformin therapy compared with peers with normal glucose tolerance (NGT). METHODS: This is a case-control observational study in youth with type 2 diabetes who were not on metformin (n = 18) compared with youth with NGT (n = 10) who were evaluated with a 2 day protocol. A 75 g OGTT was administered to measure intact glucagon-like 1 peptide (iGLP-1), gastric inhibitory polypeptide (GIP) and peptide YY (PYY). Insulinogenic index (IGI) and whole-body insulin sensitivity were calculated using glucose and insulin levels from the OGTT. Basal rates of gluconeogenesis (2H2O), glucose production ([6,6-2H2]glucose) and whole-body lipolysis ([2H5]glycerol) were measured after an overnight fast on study day 2. Youth with type 2 diabetes (n = 9) were subsequently evaluated with an identical 2 day protocol after 3 months on the metformin study. RESULTS: Compared with individuals with NGT, those with type 2 diabetes had higher fasting (7.8 ± 2.5 vs 5.1 ± 0.3 mmol/l, mean ± SD p = 0.002) and 2 h glucose concentrations (13.8 ± 4.5 vs 5.9 ± 0.9 mmol/l, p = 0.001), higher rates of absolute gluconeogenesis (10.0 ± 1.7 vs 7.2 ± 1.1 µmol [kg fat-free mass (FFM)]-1 min-1, p < 0.001) and whole-body lipolysis (5.2 ± 0.9 vs 4.0 ± 1.4 µmol kgFFM-1 min-1, p < 0.01), but lower fasting iGLP-1 concentrations (0.5 ± 0.5 vs 1.3 ± 0.7 pmol/l, p < 0.01). Metformin decreased 2 h glucose (pre metformin 11.4 ± 2.8 vs post metformin 9.9 ± 1.9 mmol/l, p = 0.04) and was associated with ~20-50% increase in IGI (median [25th-75th percentile] pre 1.39 [0.89-1.47] vs post 1.43 [0.88-2.70], p = 0.04), fasting iGLP-1 (pre 0.3 ± 0.2 vs post 1.0 ± 0.7 pmol/l, p = 0.02), 2 h iGLP (pre 0.4 ± 0.2 vs post 1.2 ± 0.9 pmol/l, p = 0.06), fasting PYY (pre 6.3 ± 2.2 vs post 10.5 ± 4.3 pmol/l, p < 0.01) and 2 h PYY (pre 6.6 ± 2.9 vs post 9.0 ± 4.0 pmol/l, p < 0.01). There was no change in BMI, insulin sensitivity or GIP concentrations pre vs post metformin. There were no differences pre vs post metformin in rates of glucose production (15.0 ± 3.9 vs 14.9 ± 2.2 µmol kgFFM-1 min-1, p = 0.84), absolute gluconeogenesis (9.9 ± 1.8 vs 9.7 ± 1.7 µmol kgFFM-1 min-1, p = 0.76) or whole-body lipolysis (5.0 ± 0.7 vs 5.3 ± 1.3 µmol kgFFM-1 min-1, p = 0.20). Post metformin iGLP-1 and PYY concentrations in youth with type 2 diabetes were comparable to levels in youth with NGT. CONCLUSIONS/INTERPRETATION: Overall, the improved postprandial blood glucose levels and increase in incretins observed in the absence of changes in insulin sensitivity and gluconeogenesis, support an enteroinsular mechanistic pathway in youth with type 2 diabetes treated with short-term metformin.

Healthcare and associated costs related to type 2 diabetes in youth and adolescence: the TODAY clinical trial experience.

The economic issues related to medical treatments in youth with type 2 diabetes (T2D) are rarely reported and thus not fully understood. The Treatment Options for type 2 Diabetes in Adolescents and Youth clinical trial of youth recently diagnosed with T2D collected healthcare and related cost information from the largest cohort studied to date. Costs related to medical treatments and expenses faced by caregivers were identified over a 2-year period from 496 participants. Data were collected by surveys and diaries to document frequency of use of diabetes care (excluding study laboratory tests), non-diabetes care services and treatments, caregiver time, and expenses related to exercise and dietary activities recommended for patients. Economic costs were derived by applying national cost values to the reported utilization frequency data. Annual medical costs in the first year varied by the treatment group, averaging $1798 in those assigned to metformin alone (M), $2971 to combination drug therapy with metformin + rosiglitazone (M + R), and $2092 to metformin + an intensive lifestyle and behavior change program (M + L). Differences were primarily due to costs related to combination drug therapy. Adult caregiver support costs were higher for participants in the lifestyle program, which was delivered in weekly sessions in the first 6 months. Expenses for purchases to enhance diet and exercise change did not vary by treatment assignment. In year 2, medication costs increased in M and M + L due to the initiation of insulin in subjects who failed to maintain glycemic control on the assigned treatment. Data are reported for use by researchers and those providing healthcare to this vulnerable patient population.

Use of Glucagon in Patients With Type 1 Diabetes.

IN BRIEF Glucagon is an invaluable tool for patients with type 1 diabetes who experience severe hypoglycemia, but little is known about the actual use of rescue glucagon in this patient population. This survey study found that patients with type 1 diabetes were not adequately prescribed glucagon or educated about the use of glucagon, and patients reported various administration issues in using it. These results strongly suggest the need for standards of practice to increase the prescribing of glucagon and the provision of initial and ongoing education about its use and administration and the development of a glucagon rescue device or a glucagon product that would eliminate the complexity of its current formulation and packaging.

Monogenic diabetes in overweight and obese youth diagnosed with type 2 diabetes: the TODAY clinical trial.

PurposeMonogenic diabetes accounts for 1-2% of diabetes cases. It is often undiagnosed, which may lead to inappropriate treatment. This study was performed to estimate the prevalence of monogenic diabetes in a cohort of overweight/obese adolescents diagnosed with type 2 diabetes (T2D).MethodsSequencing using a custom monogenic diabetes gene panel was performed on a racially/ethnically diverse cohort of 488 overweight/obese adolescents with T2D in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) clinical trial. Associations between having a monogenic diabetes variant and clinical characteristics and time to treatment failure were analyzed.ResultsMore than 4% (22/488) had genetic variants causing monogenic diabetes (seven GCK, seven HNF4A, five HNF1A, two INS, and one KLF11). Patients with monogenic diabetes had a statistically, but not clinically, significant lower body mass index (BMI) z-score, lower fasting insulin, and higher fasting glucose. Most (6/7) patients with HNF4A variants rapidly failed TODAY treatment across study arms (hazard ratio = 5.03, P = 0.0002), while none with GCK variants failed treatment.ConclusionThe finding of 4.5% of patients with monogenic diabetes in an overweight/obese cohort of children and adolescents with T2D suggests that monogenic diabetes diagnosis should be considered in children and adolescents without diabetes-associated autoantibodies and maintained C-peptide, regardless of BMI, as it may direct appropriate clinical management.

Increased gluconeogenesis in youth with newly diagnosed type 2 diabetes.

AIMS/HYPOTHESIS: The role of increased gluconeogenesis as an important contributor to fasting hyperglycaemia at diabetes onset is not known. We evaluated the contribution of gluconeogenesis and glycogenolysis to fasting hyperglycaemia in newly diagnosed youths with type 2 diabetes following an overnight fast. METHODS: Basal rates (µmol kg(FFM) (-1) min(-1)) of gluconeogenesis ((2)H2O), glycogenolysis and glycerol production ([(2)H5] glycerol) were measured in 18 adolescents (nine treatment naive diabetic and nine normal-glucose-tolerant obese adolescents). RESULTS: Type 2 diabetes was associated with higher gluconeogenesis (9.2 ± 0.6 vs 7.0 ± 0.3 µmol kg(FFM) (-1) min(-1), p < 0.01), plasma fasting glucose (7.0 ± 0.6 vs 5.0 ± 0.2 mmol/l, p = 0.004) and insulin (300 ± 30 vs 126 ± 31 pmol/l, p = 0.001). Glucose production and glycogenolysis were similar between the groups (15.4 ± 0.3 vs 12.4 ± 1.4 µmol kg(FFM) (-1) min(-1), p = 0.06; and 6.2 ± 0.8 vs 5.3 ± 0.7 µmol kg(FFM) (-1) min(-1), p = 0.5, respectively). After controlling for differences in adiposity, gluconeogenesis, glycogenolysis and glucose production were higher in diabetic youth (p ≤ 0.02). Glycerol concentration (84 ± 6 vs 57 ± 6 µmol/l, p = 0.01) and glycerol production (5.0 ± 0.3 vs 3.6 ± 0.5 µmol kg(FFM) (-1) min(-1), p = 0.03) were 40% higher in youth with diabetes. The increased glycerol production could account for only ~1/3 of substrate needed for the increased gluconeogenesis in diabetic youth. CONCLUSION/INTERPRETATIONS: Increased gluconeogenesis was a major contributor to fasting hyperglycaemia and hepatic insulin resistance in newly diagnosed untreated adolescents and was an early pathological feature of type 2 diabetes. Increased glycerol availability may represent a significant source of new carbon substrates for increased gluconeogenesis but would not account for all the carbons required to sustain the increased rates.

Precursors of hexoneogenesis within the human mammary gland.

The human mammary gland is capable of de novo synthesis of glucose and galactose (hexoneogenesis); however, the carbon source is incompletely understood. In this study, we investigated the role of acetate, glutamine, lactate and glycerol as potential carbon sources for hexoneogenesis. Healthy breastfeeding women were studied following a 24-h fast on two occasions separated by 1-3 wk. Five women were infused with [U-¹³C]lactate or [1,2-¹³C2]glutamine and five women with [U-¹³C]glycerol or [1,2-¹³C2]acetate. Enrichments of ¹³C in plasma and milk substrates were analyzed using GC-MS. Infusion of labeled lactate, glycerol, glutamine, and acetate resulted in plasma glucose being 22.0±3.7, 11.2±1.0, 2.5±0.5, and 1.3±0.2% labeled, respectively. Lactate, glutamine, or acetate did not contribute to milk glucose or galactose (0-2%). In milk, ¹³C-free glycerol enrichment was one-fourth that in plasma but free glycerol concentration in milk was fourfold higher than in plasma. Using [U-¹³C]glycerol and by accounting for tracer dilution, glycerol alone contributed to 10±2 and 69±11% of the hexoneogenesis of milk glucose and galactose, respectively. During [U-¹³C]glycerol infusion, the ratio of M3 enrichment on 4-6 carbons/M3 on 1-3 carbons of galactose was higher (P<0.05, 1.22±0.05) than those of glucose in plasma (1.05±0.03) and milk (1.07±0.02). Reanalysis of samples from a previous study involving [U-¹³C]glucose infusion alone suggested labeling a portion of galactose consistent with pentose phosphate pathway (PPP) activity. We conclude that, although lactate contributed significantly to gluconeogenesis, glycerol alone provides the vast majority of substrate for hexoneogenesis. The relative contribution of the PPP vs. the reversal Embden-Meyerhof pathway to hexoneogenesis within the human mammary gland remains to be determined.

Fluid management in pediatric patients with DKA and rates of suspected clinical cerebral edema.

OBJECTIVE: To compare outcomes of diabetic ketoacidosis (DKA) 6 yrs before and 6 yrs after changing rehydration fluids from ½ normal saline to Lactated Ringer's and decreasing the total intended fluid volume administered in the first 24 hrs from 3500 mL/m(2) /d to ≤ 2500 mL/m(2) /d at Texas Children's Hospital (TCH) in response to recommendations by the ESPE, LWPES, and ISPAD in 2004. SUBJECTS/METHODS: A retrospective cohort study was conducted in which 1868 admissions for DKA were identified and reviewed. The cohort was divided into two groups: Group A, 1998-2004, and Group B, 2004-2010. Subjects with suspected clinical cerebral edema and adverse outcomes were identified. RESULTS: Although not statistically significant, there was an equal number (n = 3) of adverse outcomes (death or neurological damage) in each group despite more than double the admissions in Group B (1264) compared with those in Group A (604). Overall, the incidence of suspected clinical cerebral edema was more than double for those admissions in which fluid resuscitation was initiated at an outside hospital (OSH) vs. at TCH (13.6 vs. 5.3%, p < 0.001). CONCLUSIONS: Decreasing the intended fluid rate during the initial 24 hrs to 2500 mL/m(2) /d and increasing the IV fluid sodium content did not significantly decrease the incidence of adverse outcomes in children with DKA. However, children transferred from an OSH had a higher incidence of suspected clinical cerebral edema. Thus, we need to more readily share our management protocols with the emergency rooms of local referring hospitals to potentially decrease the incidence of suspected clinical cerebral edema and adverse outcomes in children transferred with DKA.

De novo synthesis of milk triglycerides in humans.

UNLABELLED: Mammary gland (MG) de novo lipogenesis contributes significantly to milk fat in animals but little is known in humans. OBJECTIVE: To test the hypothesis that the incorporation of (13)C carbons from [U-(13)C]glucose into fatty acids (FA) and glycerol in triglycerides (TG) will be greater: 1) in milk than plasma TG, 2) during a high-carbohydrate (H-CHO) diet than high-fat (H-FAT) diet, and 3) during feeding than fasting. Seven healthy, lactating women were studied on two isocaloric, isonitrogenous diets. On one occasion, subjects received diets containing H-FAT or H-CHO diet for 1 wk. Incorporation of (13)C from infused [U-(13)C]glucose into FA and glycerol was measured using GC-MS and gene expression in RNA isolated from milk fat globule using microarrays. Incorporation of (13)C2 into milk FA increased with increased FA chain length from C2:0 to C12:0 but progressively declined in C14:0 and C16:0 and was not detected in FA>C16. During feeding, regardless of diets, enrichment of (13)C2 in milk FA and (13)C3 in milk glycerol were ∼ 3- and ∼ 7-fold higher compared with plasma FA and glycerol, respectively. Following an overnight fast during H-CHO and H-FAT diets, 25 and 6%, respectively, of medium-chain FA (MCFA, C6-C12) in milk were derived from glucose but increased to 75 and 25% with feeding. Expression of genes involved in FA or glycerol synthesis was unchanged regardless of diet or fast/fed conditions. The human MG is capable of de novo lipogenesis of primarily MCFA and glycerol, which is influenced by the macronutrient composition of the maternal diet.

Genetic architecture and biology of youth-onset type 2 diabetes.

The prevalence of youth-onset type 2 diabetes (T2D) and childhood obesity has been rising steadily1, producing a growing public health concern1 that disproportionately affects minority groups2. The genetic basis of youth-onset T2D and its relationship to other forms of diabetes are unclear3. Here we report a detailed genetic characterization of youth-onset T2D by analysing exome sequences and common variant associations for 3,005 individuals with youth-onset T2D and 9,777 adult control participants matched for ancestry, including both males and females. We identify monogenic diabetes variants in 2.4% of individuals and three exome-wide significant (P < 2.6 × 10-6) gene-level associations (HNF1A, MC4R, ATXN2L). Furthermore, we report rare variant association enrichments within 25 gene sets related to obesity, monogenic diabetes and ß-cell function. Many youth-onset T2D associations are shared with adult-onset T2D, but genetic risk factors of all frequencies-and rare variants in particular-are enriched within youth-onset T2D cases (5.0-fold increase in the rare variant and 3.4-fold increase in common variant genetic liability relative to adult-onset cases). The clinical presentation of participants with youth-onset T2D is influenced in part by the frequency of genetic risk factors within each individual. These findings portray youth-onset T2D as a heterogeneous disease situated on a spectrum between monogenic diabetes and adult-onset T2D.

Regulation of lipid synthesis genes and milk fat production in human mammary epithelial cells during secretory activation.

Expression of genes for lipid biosynthetic enzymes during initiation of lactation in humans is unknown. Our goal was to study mRNA expression of lipid metabolic enzymes in human mammary epithelial cell (MEC) in conjunction with the measurement of milk fatty acid (FA) composition during secretory activation. Gene expression from mRNA isolated from milk fat globule (MFG) and milk FA composition were measured from 6 h to 42 days postpartum in seven normal women. Over the first 96 h postpartum, daily milk fat output increased severalfold and mirrored expression of genes for all aspects of lipid metabolism and milk FA production, including lipolysis at the MEC membrane, FA uptake from blood, intracellular FA transport, de novo FA synthesis, FA and glycerol activation, FA elongation, FA desaturation, triglyceride synthesis, cholesterol synthesis, and lipid droplet formation. Expression of the gene for a key lipid synthesis regulator, sterol regulatory element-binding transcription factor 1 (SREBF1), increased 2.0-fold by 36 h and remained elevated over the study duration. Expression of genes for estrogen receptor 1, thyroid hormone-responsive protein, and insulin-induced 2 increased progressively to plateau by 96 h. In contrast, mRNA of peroxisome proliferator-activated receptor-γ decreased severalfold. With onset of lactation, increased de novo synthesis of FA was the most prominent change in milk FA composition and mirrored the expression of FA synthesis genes. In conclusion, milk lipid synthesis and secretion in humans is a complex process requiring the orchestration of a wide variety of pathways of which SREBF1 may play a primary role.

Types of pediatric diabetes mellitus defined by anti-islet autoimmunity and random C-peptide at diagnosis.

OBJECTIVE: To test the hypothesis that anti-islet autoantibody expression and random serum C-peptide obtained at diagnosis define phenotypes of pediatric diabetes with distinct clinical features. SUBJECTS: We analyzed 607 children aged <19 yr consecutively diagnosed with diabetes after exclusion of 13% of cases with secondary diabetes (e.g., cystic fibrosis related, steroid induced) and 7.3% of cases lacking measurement of C-peptide and/or autoantibodies. METHODS: Autoantibody positivity (A+) was defined as ≥ 1 positive out of GAD65, insulin, and ICA512 antibodies. Preserved beta-cell function (ß+) was defined as random serum C-peptide at diagnosis ≥ 0.6 ng/mL. Body mass index (BMI) was measured at median 1.2 months after diagnosis. Characteristics at diagnosis and 2 yr (range 18-30 months) after diagnosis were compared among groups. RESULTS: Autoantibody expression and C-peptide at diagnosis defined the following groups: A+ß- (52.1% of the children), A+ß+ (32.8%), A-ß+ (12.5%), and A-ß- (2.6%). These four groups differed in gender, race/ethnicity, and clinical characteristics at diagnosis [i.e., age, pubertal development, obesity/overweight, diabetic ketoacidosis, glycemia, and hemoglobin A1c (HbA1c)] and at 2 yr (i.e., clinical diagnosis, treatment, and HbA1c) (all p < 0.0001). Among all ß+ children, C-peptide >2 ng/mL was associated with lower HbA1c at onset (p = 0.0001) and, in the A+ß+ subgroup, with higher frequency of achieving HbA1c < 7% at 2 yr (p = 0.03). All three patients (0.7% of total) with monogenic diabetes (maturity onset diabetes of the young, MODY) were A-ß+ with C-peptide between 0.6 and 2 ng/mL. CONCLUSIONS: Anti-islet autoantibodies status and serum random C-peptide at diagnosis define four distinct phenotypes of pediatric diabetes with prognostic value.

Severe hypoglycemia and diabetic ketoacidosis among youth with type 1 diabetes in the T1D Exchange clinic registry.

OBJECTIVE: Severe hypoglycemia (SH) and diabetic ketoacidosis (DKA) are common serious acute complications of type 1 diabetes (T1D). The aim of this study was to determine the frequency of SH and DKA and identify factors related to their occurrence in the T1D Exchange pediatric and young adult cohort. RESEARCH DESIGN AND METHODS: The analysis included 13 487 participants in the T1D Exchange clinic registry aged 2 to <26 yr with T1D ≥2 yr. Separate logistic regression models were used to evaluate the association of baseline demographic and clinical factors with the occurrence of SH or DKA in the prior 12 months. RESULTS: Non-White race, no private health insurance, and lower household income were associated with higher frequencies of both SH and DKA (p < 0.001). SH frequency was highest in children <6 yr old (p = 0.005), but across the age range, SH was not associated with hemoglobin A1c (HbA1c) levels after controlling for other factors (p = 0.72). DKA frequency was highest in adolescents (p < 0.001) and associated with higher HbA1c (p < 0.001). CONCLUSIONS: Our data show that poor glycemic control increases the risk of DKA but does not protect against SH in youth and young adults with type 1 diabetes. The high frequencies of SH and DKA observed in disadvantaged minorities with T1D highlight the need for targeted interventions and new treatment paradigms for patients in these high risk groups.

The Metreleptin Effectiveness and Safety Registry (MEASuRE): concept, design and challenges.

BACKGROUND: Metreleptin, a recombinant analog of human leptin, is an approved therapy, adjunct to diet, to treat the metabolic complications of leptin deficiency in patients with lipodystrophy - a group of rare diseases characterized by a paucity of adipose tissue. MEASuRE (Metreleptin Effectiveness And Safety Registry) is a post-authorization, voluntary registry that gathers long-term safety and effectiveness data on metreleptin. Here, we present the aims and evolution of MEASuRE. METHODS: MEASuRE was established to collect data from patients receiving commercially supplied metreleptin in the United States (US) and European Union (EU). MEASuRE aims to determine the incidence and severity of safety events and describe the clinical characteristics and therapeutic outcomes in the metreleptin-treated population. A key feature of MEASuRE is that it accumulates data from different sources to meet post-authorization objectives. US data are received directly from treating physicians via a contract research organization-mediated electronic data capture system. In the EU, data are received via the European Registry of Lipodystrophies managed by the European Consortium of Lipodystrophies (ECLip), a platform established by researchers and physicians to advance the knowledge of lipodystrophy. MEASuRE complies with applicable regulatory requirements governing privacy, and the storage, management, and access of data. RESULTS: Leveraging processes, infrastructure, and data from the ECLip registry presented several challenges that were addressed during MEASuRE's development, including the expansion of the ECLip registry to accommodate MEASuRE-specific data elements, extensive data matching processes to ensure data consistency regardless of source, and rigorous data validation following the amalgamation of global data. Through the support of ECLip, MEASuRE is now a fully operational registry with the capacity for gathering and integrating standardized US- and EU-derived data. As of 31st October 2022, 15 US and four EU sites have participated in the MEASuRE, enrolling 85 patients globally. CONCLUSIONS: Our experiences show that a post-authorization product registry can be successfully integrated into an existing patient registry. We propose that, through collaboration with existing registries and use of their established resources, patient enrolment timelines and data collection for new registries can be expedited. The learnings presented here may be applicable to other registries with similar objectives. TRIAL REGISTRATION: NCT02325674; Registered 25 December 2014 - Retrospectively registered'. https://clinicaltrials.gov/ct2/show/NCT02325674 .

Gene regulation of UDP-galactose synthesis and transport: potential rate-limiting processes in initiation of milk production in humans.

Lactose synthesis is believed to be rate limiting for milk production. However, understanding the molecular events controlling lactose synthesis in humans is still rudimentary. We have utilized our established model of the RNA isolated from breast milk fat globule from seven healthy, exclusively breastfeeding women from 6 h to 42 days following delivery to determine the temporal coordination of changes in gene expression in the carbohydrate metabolic processes emphasizing the lactose synthesis pathway in human mammary epithelial cell. We showed that milk lactose concentrations increased from 75 to 200 mM from 6 to 96 h. Milk progesterone concentrations fell by 65% at 24 h and were undetectable by day 3. Milk prolactin peaked at 36 h and then declined progressively afterward. In concordance with lactose synthesis, gene expression of galactose kinase 2, UDP-glucose pyrophosphorylase 2 (UGP2), and phosphoglucomutase 1 increased 18-, 10-, and threefold, respectively, between 6 and 72 h. Between 6 and 96 h, gene expression of UDP-galactose transporter 2 (SLC35A2) increased threefold, whereas glucose transporter 1 was unchanged. Gene expression of lactose synthase no. 3 increased 1.7-fold by 96 h, whereas α-lactalbumin did not change over the entire study duration. Gene expression of prolactin receptor (PRLR) and its downstream signal transducer and activator of transcription complex 5 (STAT5) were increased 10- and 2.5-fold, respectively, by 72 h. In summary, lactose synthesis paralleled the induction of gene expression of proteins involved in UDP-galactose synthesis and transport, suggesting that they are potentially rate limiting in lactose synthesis and thus milk production. Progesterone withdrawal may be the signal that triggers PRLR signaling via STAT5, which may in turn induce UGP2 and SLC35A2 expression.

Ablation of ghrelin receptor in leptin-deficient ob/ob mice has paradoxical effects on glucose homeostasis when compared with ablation of ghrelin in ob/ob mice.

The orexigenic hormone ghrelin is important in diabetes because it has an inhibitory effect on insulin secretion. Ghrelin ablation in leptin-deficient ob/ob (Ghrelin(-/-):ob/ob) mice increases insulin secretion and improves hyperglycemia. The physiologically relevant ghrelin receptor is the growth hormone secretagogue receptor (GHS-R), and GHS-R antagonists are thought to be an effective strategy for treating diabetes. However, since some of ghrelin's effects are independent of GHS-R, we have utilized genetic approaches to determine whether ghrelin's effect on insulin secretion is mediated through GHS-R and whether GHS-R antagonism indeed inhibits insulin secretion. We investigated the effects of GHS-R on glucose homeostasis in Ghsr-ablated ob/ob mice (Ghsr(-/-):ob/ob). Ghsr ablation did not rescue the hyperphagia, obesity, or insulin resistance of ob/ob mice. Surprisingly, Ghsr ablation worsened the hyperglycemia, decreased insulin, and impaired glucose tolerance. Consistently, Ghsr ablation in ob/ob mice upregulated negative ß-cell regulators (such as UCP-2, SREBP-1c, ChREBP, and MIF-1) and downregulated positive ß-cell regulators (such as HIF-1α, FGF-21, and PDX-1) in whole pancreas; this suggests that Ghsr ablation impairs pancreatic ß-cell function in leptin deficiency. Of note, Ghsr ablation in ob/ob mice did not affect the islet size; the average islet size of Ghsr(-/-):ob/ob mice is similar to that of ob/ob mice. In summary, because Ghsr ablation in leptin deficiency impairs insulin secretion and worsens hyperglycemia, this suggests that GHS-R antagonists may actually aggravate diabetes under certain conditions. The paradoxical effects of ghrelin ablation and Ghsr ablation in ob/ob mice highlight the complexity of the ghrelin-signaling pathway.

Effect of ghrelin on glucose regulation in mice.

Improvement of glucose metabolism after bariatric surgery appears to be from the composite effect of the alterations in multiple circulating gut hormone concentrations. However, their individual effect on glucose metabolism during different conditions is not clear. The objective of this study was to determine whether ghrelin has an impact on glycogenolysis, gluconeogenesis, and insulin sensitivity (using a mice model). Rate of appearance of glucose, glycogenolysis, and gluconeogenesis were measured in wild-type (WT), ghrelin knockout (ghrelin(-/-)), and growth hormone secretagogue receptor knockout (Ghsr(-/-)) mice in the postabsorptive state. The physiological nature of the fasting condition was ascertained by a short-term fast commenced immediately at the end of the dark cycle. Concentrations of glucose and insulin were measured, and insulin resistance and hepatic insulin sensitivity were calculated. Glucose concentrations were not different among the groups during the food-deprived period. However, plasma insulin concentrations were lower in the ghrelin(-/-) and Ghsr(-/-) than WT mice. The rates of gluconeogenesis, glycogenolysis, and indexes of insulin sensitivity were higher in the ghrelin(-/-) and Ghsr(-/-) than WT mice during the postabsorptive state. Insulin receptor substrate 1 and glucose transporter 2 gene expressions in hepatic tissues of the ghrelin(-/-) and Ghsr(-/-) were higher compared with that in WT mice. This study demonstrates that gluconeogenesis and glycogenolysis are increased and insulin sensitivity is improved by the ablation of the ghrelin or growth hormone secretagogue receptor in mice.

Beta cell function and BMI in ethnically diverse children with newly diagnosed autoimmune type 1 diabetes.

OBJECTIVE: To examine the relationship between BMI and beta-cell function at diagnosis of autoimmune type 1 diabetes (T1D) in a large group of ethnically diverse children. METHODS: Cross-sectional analysis of 524 children (60.8% White, 19.5% Hispanic, 14.5% African-American, 5.2% other non-Hispanic; mean age = 9.8 yr [SD = 2.5]) with newly diagnosed autoimmune T1D. RESULTS: As much as 22.2% of children were overweight or obese. Median random serum C-peptide was 0.40 ng/mL (25th-75th percentiles = 0.3-0.8), with median glycemia of 366 mg/dL (25th-75th percentiles = 271-505). Median C-peptide was 0.3, 0.5, 0.7, and 0.85 ng/mL, respectively, in underweight, normal weight, overweight, and obese children (p < 0.0001, Kruskal-Wallis). In the final model (p < 0.0001), the odds of having preserved C-peptide (≥0.6 ng/mL) were increased by 2.4-fold (95% CI = 1.2-4.9, p < 0.015) and 4.1-fold (1.9-8.5, p < 0.0001), respectively, in overweight and obese compared to lean children; 1.3-fold per each year of age; 2.5-fold in girls compared to boys; 4-fold in children who presented without, compared to with, diabetes ketoacidosis (DKA); and decreased by 21% for each point increase in HbA1c. Tanner stage, race/ethnicity, glycemia, and number of anti-islet antibodies expressed were not independently associated with preserved C-peptide. The association between BMI and C-peptide levels was significant in children with and without preserved C-peptide. Excluding patients who presented with DKA and/or using BMI obtained 5 wk after diagnosis did not alter the results. CONCLUSION: Obese and overweight children compared to lean children have greater beta-cell function at the onset of autoimmune T1D. Prospective studies on the relationships among BMI, beta-cell function, and progression to clinical T1D are warranted.

Elucidating Human Milk Oligosaccharide biosynthetic genes through network-based multi-omics integration.

Human Milk Oligosaccharides (HMOs) are abundant carbohydrates fundamental to infant health and development. Although these oligosaccharides were discovered more than half a century ago, their biosynthesis in the mammary gland remains largely uncharacterized. Here, we use a systems biology framework that integrates glycan and RNA expression data to construct an HMO biosynthetic network and predict glycosyltransferases involved. To accomplish this, we construct models describing the most likely pathways for the synthesis of the oligosaccharides accounting for >95% of the HMO content in human milk. Through our models, we propose candidate genes for elongation, branching, fucosylation, and sialylation of HMOs. Our model aggregation approach recovers 2 of 2 previously known gene-enzyme relations and 2 of 3 empirically confirmed gene-enzyme relations. The top genes we propose for the remaining 5 linkage reactions are consistent with previously published literature. These results provide the molecular basis of HMO biosynthesis necessary to guide progress in HMO research and application with the goal of understanding and improving infant health and development.