Cross-sectional and Test-Retest Characterization of PET with [(18)F]FP-(+)-DTBZ for ß Cell Mass Estimates in Diabetes.

PURPOSE: The vesicular monoamine transporter, type 2 (VMAT2) is expressed by insulin producing ß cells and was evaluated as a biomarker of ß cell mass (BCM) by positron emission tomography (PET) with [(18)F]fluoropropyl-dihydrotetrabenazine ([(18)F]FP-(+)-DTBZ). PROCEDURES: We evaluated the feasibility of longitudinal pancreatic PET VMAT2 quantification in the pancreas in two studies of healthy controls and patients with type 1 or 2 diabetes. VMAT2 binding potential (BPND) was estimated voxelwise using a reference tissue method in a cross-sectional study, followed by assessment of reproducibility using a test-retest paradigm. Metabolic function was evaluated by stimulated c-peptide measurements. RESULTS: Pancreatic BPND was significantly decreased in patients with type 1 diabetes relative to controls and the test-retest variability was 9.4%. CONCLUSIONS: Pancreatic VMAT2 content is significantly reduced in long-term diabetes patients relative to controls and repeat scans are sufficiently reproducible to suggest the feasibility clinically VMAT2 measurements in longitudinal studies of new onset diabetes.

Depressive symptoms and quality of life in adolescents with type 2 diabetes: baseline data from the TODAY study.

OBJECTIVE: The study objective was to examine the prevalence of depressive symptoms and relationships to quality of life and demographics in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study's large, ethnically diverse youth with type 2 diabetes. RESEARCH DESIGN AND METHODS: A total of 704 youth with type 2 diabetes <2 years' duration, aged 10-17 years, and BMI ≥85th percentile completed depressive symptoms and quality of life measures. RESULTS: Some 14.8% reported clinically significant depressive symptoms, and older girls had significantly higher rates than older boys. CONCLUSIONS: Rates of significant depressive symptoms were similar to those of healthy adolescents and lower than those of teens with type 1 diabetes. Elevated depressive symptoms, particularly in older girls, suggest clinicians assess vulnerability.

School-based intervention acutely improves insulin sensitivity and decreases inflammatory markers and body fatness in junior high school students.

CONTEXT: Risk factors for type 2 diabetes mellitus (T2DM) include obesity, family history, dyslipidemia, a proinflammatory state, impaired insulin secretory capacity, and insulin resistance. OBJECTIVE: The aim of this study was to examine the effects of a 3- to 4-month school-based intervention consisting of health, nutrition, and exercise classes plus an aerobic exercise program on diabetes risk. DESIGN: This study was a randomized before/after controlled trial. METHODS: Seventy-three eighth-grade students in a predominantly Hispanic New York City public school were divided into a control group (studied twice without receiving the intervention) and an experimental group (studied before and after the intervention). OUTCOME MEASURES: We measured body fatness (bioelectrical impedance), insulin sensitivity, beta-cell function (insulin release in response to an iv glucose load corrected for insulin sensitivity), lipid profiles, and circulating concentrations of IL-6, C-reactive protein, adiponectin, and TNF-alpha. RESULTS: Participation in the intervention was associated with significant reductions in body fatness, insulin resistance, and circulating concentrations of C-reactive protein and IL-6, irrespective of somatotype on enrollment. CONCLUSION: Short-term school-based health, nutrition, and exercise intervention is beneficial to all students and affects multiple diabetes risk factors.

beta-Cell function and insulin sensitivity in early adolescence: association with body fatness and family history of type 2 diabetes mellitus.

The prevalence of type 2 diabetes mellitus (T2DM) among adolescents has increased 5- to 10-fold over the past decade. T2DM results from pancreatic beta-cell dysfunction and insulin resistance. Using rapid iv glucose tolerance testing, we examined beta-cell function and insulin resistance in 72 predominantly Latino eighth grade students (41 males and 31 females; mean +/- sem age, 13.6 +/- 0.1 yr). Thirty-six percent of the children had body mass indexes above the 85th percentile for age and gender, and 50% had a first- or second-degree relative with T2DM. Overweight children were five times more likely to be in the highest quartile for insulin resistance. Children with a family history of T2DM were five times more likely to be in the lowest quartile for insulin secretory capacity, 4.5 times more likely to be in the lowest quartile for glucose disposal, and three times more likely to be in the lowest quartile for insulin resistance. These findings are consistent with a model for the physiology of T2DM in which a familial beta-cell dysfunction is unmasked by increasing insulin resistance secondary to overweight in this predominantly Latino population.