Preventing severe hypoglycemia in adults with type 2 diabetes (PHT2): Design, delivery and evaluation framework for a randomized controlled trial.

BACKGROUND: Severe hypoglycemia is a common and feared complication of medications used to lower blood glucose levels in individuals with diabetes. Psychoeducational interventions can prevent severe hypoglycemia in individuals with type 1 diabetes (T1D). We aim to determine the effectiveness of this approach among adults with type 2 diabetes (T2D) at elevated risk for severe hypoglycemia. METHODS: Preventing Hypoglycemia in Type 2 diabetes (PHT2) is a two-arm, parallel, randomized controlled trial. Participants are eligible if they are adults with T2D receiving care at an integrated group practice in Washington state and have experienced one or more episodes of severe hypoglycemia in the prior 12 months or have impaired awareness of hypoglycemia (Gold score ≥ 4). Participants are randomized to proactive nurse care management with or without my hypo compass, an evidence-based, psychoeducational intervention combining group and individual self-management training. For this study, my hypo compass was adapted to be suitable for adults with T2D and from an in-person to a virtual intervention over videoconference and telephone. The primary outcome is any self-reported severe hypoglycemia in the 12 months following the start of the intervention. Secondary outcomes include biochemical measures of hypoglycemia, self-reported hypoglycemia awareness, fear of hypoglycemia, and emergency department visits and hospitalizations for severe hypoglycemia. The study includes a process evaluation to assess implementation fidelity and clarify the causal pathway. CONCLUSION: The PHT2 trial will compare the effectiveness of two approaches for reducing severe hypoglycemia in adults with T2D. TRIAL REGISTRATION: clinicaltrials.gov, # NCT04863872.

Validation of Igls Criteria for Islet Transplant Functional Status Using Person-Reported Outcome Measures in a Cross-Sectional Study.

Associations between islet graft function and well-being in islet transplant recipients requiring exogenous insulin remain unclear. This cross-sectional analysis compared person-reported outcome measures in 15 adults with type 1 diabetes whose islet transplants were classified according to Igls criteria as "Good" (n = 5), "Marginal" (n = 4) and "Failed" (n = 6) graft function. At a mean of 6.2 years post-first islet transplant, 90% reduction in severe hypoglycaemia was maintained in all groups, with HbA1c (mean ± SD mmol/mol) 49 ± 4 in recipients with "Good" function; 56 ± 5 ("Marginal"); and 69 ± 25 ("Failed"). Self-reported impaired awareness of hypoglycaemia persisted in all groups but those with "Good" function were more likely to experience symptoms during hypoglycaemia. "Marginal" function was associated with greater fear of hypoglycaemia (HFS-II score: "Marginal": 113 [95, 119]; "Failed": 63 [42, 93] (p = 0.082); "Good": 33 [29, 61]) and severe anxiety (GAD7: "Marginal"): 21 [17, 21]; "Failed": 6 [6, 6] "Good": 6 [3, 11]; (p = 0.079)), diabetes distress and low mood. Despite clear evidence of ongoing clinical benefit, Igls criteria 'Marginal' function is associated with sub-optimal well-being, including greater fear of hypoglycaemia and severe anxiety. This study provides person-reported validation that "Good" and "Marginal" graft function are differentiated by general and diabetes-specific subjective well-being, suggesting those with "Marginal" function may benefit from further intervention, including re-transplantation.

Type 1 diabetes patients increase CXCR4+ and CXCR7+ haematopoietic and endothelial progenitor cells with exercise, but the response is attenuated.

Exercise mobilizes angiogenic cells, which stimulate vascular repair. However, limited research suggests exercise-induced increase of endothelial progenitor cell (EPCs) is completely lacking in type 1 diabetes (T1D). Clarification, along with investigating how T1D influences exercise-induced increases of other angiogenic cells (hematopoietic progenitor cells; HPCs) and cell surface expression of chemokine receptor 4 (CXCR4) and 7 (CXCR7), is needed. Thirty T1D patients and 30 matched non-diabetes controls completed 45 min of incline walking. Circulating HPCs (CD34+, CD34+CD45dim) and EPCs (CD34+VEGFR2+, CD34+CD45dimVEGFR2+), and subsequent expression of CXCR4 and CXCR7, were enumerated by flow cytometry at rest and post-exercise. Counts of HPCs, EPCs and expression of CXCR4 and CXCR7 were significantly lower at rest in the T1D group. In both groups, exercise increased circulating angiogenic cells. However, increases was largely attenuated in the T1D group, up to 55% lower, with CD34+ (331 ± 437 Δcells/mL vs. 734 ± 876 Δcells/mL p = 0.048), CD34+VEGFR2+ (171 ± 342 Δcells/mL vs. 303 ± 267 Δcells/mL, p = 0.006) and CD34+VEGFR2+CXCR4+ (126 ± 242 Δcells/mL vs. 218 ± 217 Δcells/mL, p = 0.040) significantly lower. Exercise-induced increases of angiogenic cells is possible in T1D patients, albeit attenuated compared to controls. Decreased mobilization likely results in reduced migration to, and repair of, vascular damage, potentially limiting the cardiovascular benefits of exercise.Trial registration: ISRCTN63739203.

Postexercise Glycemic Control in Type 1 Diabetes Is Associated With Residual ß-Cell Function.

OBJECTIVE: To investigate the impact of residual ß-cell function on continuous glucose monitoring (CGM) outcomes following acute exercise in people with type 1 diabetes (T1D). RESEARCH DESIGN AND METHODS: Thirty participants with T1D for ≥3 years were recruited. First, participants wore a blinded CGM unit for 7 days of free-living data capture. Second, a 3-h mixed-meal test assessed stimulated C-peptide and glucagon. Peak C-peptide was used to allocate participants into undetectable (Cpepund <3 pmol/L), low (Cpeplow 3-200 pmol/L), or high (Cpephigh >200 pmol/L) C-peptide groups. Finally, participants completed 45 min of incline treadmill walking at 60% VO2peak followed by a further 48-h CGM capture. RESULTS: CGM parameters were comparable across groups during the free-living observation week. In the 12- and 24-h postexercise periods (12 h and 24 h), the Cpephigh group had a significantly greater amount of time spent with glucose 3.9-10 mmol/L (12 h, 73.5 ± 27.6%; 24 h, 76.3 ± 19.2%) compared with Cpeplow (12 h, 43.6 ± 26.1%, P = 0.027; 24 h, 52.3 ± 25.0%, P = 0.067) or Cpepund (12 h, 40.6 ± 17.0%, P = 0.010; 24 h, 51.3 ± 22.3%, P = 0.041). Time spent in hyperglycemia (12 h and 24 h glucose >10 and >13.9 mmol/L, P < 0.05) and glycemic variability (12 h and 24 h SD, P < 0.01) were significantly lower in the Cpephigh group compared with Cpepund and Cpeplow. Change in CGM outcomes from pre-exercise to 24-h postexercise was divergent: Cpepund and Cpeplow experienced worsening (glucose 3.9-10 mmol/L: -9.1% and -16.2%, respectively), with Cpephigh experiencing improvement (+12.1%) (P = 0.017). CONCLUSIONS: Residual ß-cell function may partially explain the interindividual variation in the acute glycemic benefits of exercise in individuals with T1D. Quantifying C-peptide could aid in providing personalized and targeted support for exercising patients.

Metformin improves the angiogenic potential of human CD34⁺ cells co-incident with downregulating CXCL10 and TIMP1 gene expression and increasing VEGFA under hyperglycemia and hypoxia within a therapeutic window for myocardial infarction.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in patients with diabetes mellitus (DM). To identify the most effective treatment for CVD, it is paramount to understand the mechanism behind cardioprotective therapies. Although metformin has been shown to reduce CVD in Type-2 DM clinical trials, the underlying mechanism remains unexplored. CD34(+) cell-based therapies offer a new treatment approach to CVD. The aim of this study was to investigate the effect of metformin on the angiogenic properties of CD34(+) cells under conditions mimicking acute myocardial infarction in diabetes. METHODS: CD34(+) cells were cultured in 5.5 or 16.5 mmol/L glucose ± 0.01 mmol/L metformin and then additionally ± 4 % hypoxia. The paracrine function of CD34(+) cell-derived conditioned medium was assessed by measuring pro-inflammatory cytokines, vascular endothelial growth factor A (VEGFA), and using an in vitro tube formation assay for angiogenesis. Also, mRNA of CD34(+) cells was assayed by microarray and genes of interest were validated by qRT-PCR. RESULTS: Metformin increased in vitro angiogenesis under hyperglycemia-hypoxia and augmented the expression of VEGFA. It also reduced the angiogenic-inhibitors, chemokine (C-X-C motif) ligand 10 (CXCL10) and tissue inhibitor of metalloproteinase 1 (TIMP1) mRNAs, which were upregulated under hyperglycemia-hypoxia. In addition metformin, increased expression of STEAP family member 4 (STEAP4) under euglycemia, indicating an anti-inflammatory effect. CONCLUSIONS: Metformin has a dual effect by simultaneously increasing VEGFA and reducing CXCL10 and TIMP1 in CD34(+) cells in a model of the diabetic state combined with hypoxia. Therefore, these angiogenic inhibitors are promising therapeutic targets for CVD in diabetic patients. Moreover, our data are commensurate with a vascular protective effect of metformin and add to the understanding of underlying mechanisms.

Reference genes for expression studies in hypoxia and hyperglycemia models in human umbilical vein endothelial cells.

Human umbilical vein endothelial cell (HUVEC)-based gene expression studies performed under hypoxia and/or hyperglycemia show huge potential for modeling endothelial cell response in cardiovascular disease and diabetes. However, such studies require reference genes that are stable across the whole range of experimental conditions. These reference genes have not been comprehensively defined to date. We applied human genome-wide microarrays and quantitative real-time PCR (qRT-PCR) on RNA obtained from primary HUVEC cultures that were incubated for 24 hr either in euglycemic or in hyperglycemic conditions and then subjected to short-term CoCl2-induced hypoxia for 1, 3, or 12 hr. Using whole-transcript arrays, we selected 10 commonly used reference genes with no significant expression variation across eight different conditions. These genes were ranked using NormFinder software according to their stability values. Consequently, five genes were selected for validation by qRT-PCR. These were ribosomal protein large P0 (RPLP0), transferrin receptor (TFRC), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ß-glucuronidase (GUSB), and ß-actin (ACTB). All five genes displayed stable expression under hyperglycemia. However, only RPLP0 and TFRC genes were stable under hypoxia up to 12 hr. Under hyperglycemia combined with hypoxia up to 12 hr, the expression of RPLP0, TFRC, GUSB, and ACTB genes remained unchanged. Our findings strongly confirm that RPLP0 and TFRC are the most suitable reference genes for HUVEC gene expression experiments subjected to hypoxia and/or hyperglycemia for the given experimental conditions. We provide further evidence that even commonly known references genes require experimental validation for all conditions involved.

Public and patient research priorities for orthostatic hypotension.

With a rapidly expanding older population and increased survival of older people with chronic disease, we can expect to see increasing numbers of people with orthostatic hypotension (OH). Unfortunately the evidence base for people with OH, with particular relevance to older people, has not kept up and has resulted in a real lack of progress and little good evidence. There are several areas of research that could potentially benefit patients but establishing which ones are priority areas requires public and patient involvement (PPI). This process includes people/patients in the research team to maximise the relevance, success and translation of the research. This brief report describes the early involvement of older people in prioritising the research question, methods to improve adherence during a trial and the preferred methods to disseminate research output. The individuals' priority was to research non-pharmacological treatment strategies and to improve the education of patients about their condition. Education was felt to be the best strategy to promote adherence during a trial, with change in symptoms and quality of life felt to be the most important outcome measures as opposed to blood pressure. This report offers guidance for academics that are undertaking OH-related research and how they can improve its relevance and increase its translation into clinical practice.