Background: The safety and effectiveness of the in-home use of a hybrid closed-loop (HCL) system that automatically increases, decreases, and suspends insulin delivery in response to continuous glucose monitoring were investigated.Methods: Adolescents (n = 30, ages 14–21 years) and adults (n = 94, ages 22–75 years) with type 1 diabetes participated in a multicenter (nine sites in the United States, one site in Israel) pivotal trial. The Medtronic MiniMed® 670G system was used during a 2-week run-in phase without HCL control, or Auto Mode, enabled (Manual Mode) and, thereafter, with Auto Mode enabled during a 3-month study phase. A supervised hotel stay (6 days/5 nights) that included a 24-h frequent blood sample testing with a reference measurement (i-STAT) occurred during the study phase.Results: Adolescents (mean ± standard deviation [SD] 16.5 ± 2.29 years of age and 7.7 ± 4.15 years of diabetes) used the system for a median 75.8% (interquartile range [IQR] 68.0%–88.4%) of the time (2977 patient-days). Adults (mean ± SD 44.6 ± 12.79 years of age and 26.4 ± 12.43 years of diabetes) used the system for a median 88.0% (IQR 77.6%–92.7%) of the time (9412 patient-days). From baseline run-in to the end of study phase, adolescent and adult HbA1c levels decreased from 7.7% ± 0.8% to 7.1% ± 0.6% (P < 0.001) and from 7.3% ± 0.9% to 6.8% ± 0.6% (P < 0.001, Wilcoxon signed-rank test), respectively. The proportion of overall in-target (71–180 mg/dL) sensor glucose (SG) values increased from 60.4% ± 10.9% to 67.2% ± 8.2% (P < 0.001) in adolescents and from 68.8% ± 11.9% to 73.8% ± 8.4% (P < 0.001) in adults. During the hotel stay, the proportion of in-target i-STAT® blood glucose values was 67.4% ± 27.7% compared to SG values of 72.0% ± 11.6% for adolescents and 74.2% ± 17.5% compared to 76.9% ± 8.3% for adults. There were no severe hypoglycemic or diabetic ketoacidosis events in either cohort.Conclusions: HCL therapy was safe during in-home use by adolescents and adults and the study phase demonstrated increased time in target, and reductions in HbA1c, hyperglycemia and hypoglycemia, compared to baseline. Trial Registration: identifier: NCT02463097.

Conflict of interest:The authors have declared that no conflict of interest exists. Nonstandard abbreviations used: insulin receptor (IR); endothelin-1 (ET-1); vascular endothelial cell insulin receptor knockout (VENIRKO); glucose-tolerance test (GTT); insulintolerance tests (ITT); systolic blood pressure (SBP); mean blood pressure (MBP); diastolic blood pressure (DBP); heart rate (HR); glucose infusion rate (GIR); lipoprotein lipase (LPL). these animals and explore the role of the insulin receptor in retinal neovascularization. MethodsGeneration of mice and genotyping. VENIRKO mice were generated using the Cre-loxP system. Mice carrying an IR gene in which exon 4 is flanked by lox sites (20) were bred with a transgenic mice expressing Cre recombinase under control of the Tie2 promoter-enhancer. Previous studies have shown that Tie2 expression is limited to vascular endothelial cells and the endocardial cushion (21). As a result of the complex breeding, all the mice in these experiments have a mixed genetic background, including contributions from 129Sv, C57Bl/6, SJL, FVB, and DBA strains. To minimize the difference of genetic background, we used littermates from same breeding pairs as controls. Genotyping of the mice for the Cre transgene and the floxed IR alleles was performed by genomic PCR, using specific primers that allow identification of the presence or absence of the Tie2-Cre transgene and heterozygosity or homozygosity of the IR gene for the floxed or wild-type allele (22). Animals were housed on a 12-h light/dark cycle and were fed a standard rodent chow. All protocols for animal use and euthanasia were reviewed and approved by the Animal Care Committee of the Joslin Diabetes Center and were in accordance with NIH guidelines. All experiments were carried out in male mice, except as otherwise noted.Endothelial culture and evaluation of the Cre-mediated recombination of IR in vascular endothelial cells. Two approaches were used to derive microvascular endothelium for primary culture. Cerebrovascular microvessels were isolated by filtration of brain homogenates and digestion with collagenase (23). The digested vessels were filtered sequentially through nylon meshes of three different pore sizes 210, 88, and 55 µm, respectively. The microvessels retained on 88-and 55-µm filters were plated on 30-mm fibronectin-coated dishes and incubated in DMEM medium containing 10% FCS and 2% bovine brain EGF for 7-10 days. Nonendothelial cells were scraped off using a cotton bar under microscopic visualization. Cultures that were considered more than 95% pure based on morphological examination were used to prepare genomic DNA. Cre-mediated recombination of IR gene was analyzed by PCR using primers surrounding exon 4, as described previously (22).To obtain enough endothelial cells to prepare RNA for real-time quantitative RT-PCR, primary cultures of endothelial cells were established using cells immunoselected from lungs (24). Briefly, a cell suspension was prepared from lungs by digestion with collagenase (1 mg/ml) for...

Background-Rad (Ras associated with diabetes) GTPase is the prototypic member of a subfamily of Ras-related small G proteins. The aim of the present study was to define whether Rad plays an important role in mediating cardiac hypertrophy. Methods and Results-We document for the first time that levels of Rad mRNA and protein were decreased significantly in human failing hearts (nϭ10) compared with normal hearts (nϭ3; PϽ0.01). Similarly, Rad expression was decreased significantly in cardiac hypertrophy induced by pressure overload and in cultured cardiomyocytes with hypertrophy induced by 10 mol/L phenylephrine. Gain and loss of Rad function in cardiomyocytes significantly inhibited and increased phenylephrine-induced hypertrophy, respectively. In addition, activation of calcium-calmodulin-dependent kinase II (CaMKII), a strong inducer of cardiac hypertrophy, was significantly inhibited by Rad overexpression. Conversely, downregulation of CaMKII␦ by RNA interference technology attenuated the phenylephrine-induced hypertrophic response in cardiomyocytes in which Rad was also knocked down. To further elucidate the potential role of Rad in vivo, we generated Rad-deficient mice and demonstrated that they were more susceptible to cardiac hypertrophy associated with increased CaMKII phosphorylation than wild-type littermate controls. Conclusions-The present data document for the first time that Rad is a novel mediator that inhibits cardiac hypertrophy through the CaMKII pathway. The present study will have significant implications for understanding the mechanisms of cardiac hypertrophy and setting the basis for the development of new strategies for treatment of cardiac hypertrophy.