Project description:Background and aimEndothelial dysfunction is involved in the pathogenesis of atherosclerosis and is typically present in older adults with type 1 diabetes (T1D). In young adults, we aimed to assess the impact of T1D on endothelial function as detected by digital peripheral arterial tonometry (PAT) and its relationship with cardiovascular risk factors and long term glycemic control.Materials and methodsReactive hyperemia index (RHI) as a measure of endothelial function was assessed by PAT in 46 T1D patients and 32 healthy controls. All were participants in the "Atherosclerosis and Childhood Diabetes" study, with baseline values registered five years previously. Annual measurements of HbA1c for assessment of glycemic burden were provided by the Norwegian Childhood Diabetes Registry.ResultsThe diabetes patients had a mean age of 20.8 years, a median duration of diabetes of 10.0 years and a mean HbA1c of 8.7%. RHI was not significantly decreased in the diabetes group, mean 2.00 (SD = 0.59) vs. 2.21 (SD = 0.56), p = .116. There was no gender difference or any associations with traditional risk factors. Furthermore, there was no significant association between RHI and either HbA1c or long term glycemic burden.ConclusionsRHI as a measure of endothelial function was preserved in young adults with T1D compared with healthy controls.
Project description:Data indicate endothelium-dependent dilation (EDD) may be preserved in the skeletal muscle microcirculation of young, obese adults. Preserved EDD might be mediated by compensatory mechanisms, impeding insight into preclinical vascular dysfunction. We aimed to determine the functional roles of nitric oxide synthase (NOS) and cyclooxygenase (COX) toward EDD in younger obese adults. We first hypothesized EDD would be preserved in young, obese adults. Further, we hypothesized a reduced contribution of NOS in young, obese adults would be replaced by increased COX signaling. Microvascular EDD was assessed with Doppler ultrasound and brachial artery infusion of acetylcholine (ACh) in younger (27 ± 1 year) obese (n = 29) and lean (n = 46) humans. Individual and combined contributions of NOS and COX were examined with intra-arterial infusions of l-NMMA and ketorolac, respectively. Vasodilation was quantified as an increase in forearm vascular conductance (ΔFVC). Arterial endothelial cell biopsies were analyzed for protein expression of endothelial nitric oxide synthase (eNOS). ΔFVC to ACh was similar between groups. After l-NMMA, ΔFVC to ACh was greater in obese adults (p < 0.05). There were no group differences in ΔFVC to ACh with ketorolac. With combined NOS-COX inhibition, ΔFVC was greater in obese adults at the intermediate dose of ACh. Surprisingly, arterial endothelial cell eNOS and phosphorylated eNOS were similar between groups. Younger obese adults exhibit preserved EDD and eNOS expression despite functional dissociation of NOS-mediated vasodilation and similar COX signaling. Compensatory NOS- and COX-independent vasodilatory mechanisms conceal reduced NOS contributions in otherwise healthy obese adults early in life, which may contribute to vascular dysfunction.
Project description:ObjectiveImpaired insulin sensitivity is associated with hyperfiltration (i.e., elevated glomerular filtration rate [GFR]) in adolescents with type 2 diabetes (T2D) and adults with prediabetes. Yet, these relationships are based on studies that relied on estimated GFR (eGFR), estimates of insulin sensitivity, or both. We aimed to verify the relationship between insulin sensitivity and renal hemodynamic function by gold standard methods in adults with T2D.Research design and methodsInsulin sensitivity was assessed by hyperinsulinemic-euglycemic clamp (M value) (glucose infusion rate in mg/kglean/min) and renal hemodynamic function by urinary inulin (GFR) and para-aminohippuric acid (effective renal plasma flow [ERPF]) clearances in participants with T2D without overt kidney disease. Filtration fraction (FF) (GFR/ERPF) was calculated. Relationships between insulin sensitivity and renal hemodynamic parameters were examined by multivariable linear regression. Renal hemodynamic parameters were examined across tertiles of M values.ResultsWe tested 44 adults with T2D, of whom 77% were male, with mean ± SD age 63 ± 7 years, BMI 31.2 ± 4.0 kg/m2, and HbA1c 7.4 ± 0.6%. Average GFR was 110 ± 26 mL/min, with an FF of 22.1 ± 2.8% and median 24-h urinary albumin excretion of 11.3 mg (interquartile range 5.8-17.0). Average M value was 5.6 ± 2.9 mg/kglean/min. Insulin sensitivity inversely correlated with GFR (r = -0.44, P < 0.01) and FF (r = -0.40, P < 0.01), and these associations remained significant after multivariable adjustments for age, sex, renin-angiotensin system inhibitor use, and HbA1c. In addition, GFR, FF, and urinary albumin excretion were highest in the participants in the lowest M value tertile.ConclusionsFor the first time, we demonstrate that impaired insulin sensitivity is associated with intrarenal hemodynamic dysfunction by gold standard techniques in adults with T2D treated with metformin monotherapy.
Project description:In type 1 diabetes (T1D), impaired insulin sensitivity may contribute to the development of diabetic kidney disease (DKD) through alterations in kidney oxidative metabolism. Young adults with T1D and healthy controls underwent single-cell RNA sequencing, and spatial metabolomics to assess this relationship.
Project description:Heart failure (HF) is associated with endothelial dysfunction. Vascular function per se plays an important role in cardiac function, whether it is a cause or consequence. However, there is no information on vascular function in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). The purpose of this study was to evaluate vascular function in patients with ATTRwt-CM. We measured flow-mediated vasodilation (FMD) as an index of endothelial function and nitroglycerine-induced vasodilation (NID) as an index of vascular smooth muscle function and brachial artery intima-media thickness (bIMT) and brachial-ankle pulse wave velocity (baPWV) as indices of arterial stiffness in 22 patients with ATTRwt-CM and in 22 one-by-one matched control patients using vascular function confounding factors. FMD was significantly greater in patients with ATTRwt-CM than in the controls (5.4 ± 3.4% versus 3.5 ± 2.4%, p = 0.038) and the N-terminal pro-brain natriuretic peptide (NT-proBNP) level was significantly greater in patients with ATTRwt-CM than in the controls (2202 ± 1478 versus 470 ± 677 pg/mL, p < 0.001). There were no significant differences in NID, bIMT or baPWV between the two groups. There was a significant relationship between NT-proBNP and FMD in patients with ATTRwt-CM (r = 0.485, p = 0.022). NT-proBNP showed no significant relationships with NID, bIMT or baPWV. Conclusions: Endothelial function was preserved in patients with ATTRwt-CM. Patients with ATTRwt-CM may have compensatory effects with respect to endothelial function through elevation of BNP.
Project description:Preclinical models of type 1 diabetes mellitus exhibit marked declines in skeletal muscle health including significant impairments in muscle repair. The present study investigated, for the first time, whether muscle repair was altered in young adults with uncomplicated type 1 diabetes (T1D) following damaging exercise.In this cohort study, eighteen physically-active young adults (M=22.1, SEM=0.9 years) with T1D (n, male/female=4/5; MHbA1c= 58, SEMHbA1c=5.9 mmol/mol) and without T1D (n, male/female=4/5) performed 300 unilateral eccentric contractions (90°s-1) of the knee extensors. Prior to exercise, at 48-hours and at 96-hours after exercise, participants gave a venous blood sample and vastus lateralis biopsy and performed a maximal voluntary isometric knee extension. Skeletal muscle extracellular matrix content, and satellite cell content/proliferation were assessed by immunofluorescence. Transmission electron microscopy was used to quantify ultrastructural damage.Maximal isometric strength was comparable between T1D and their sex-matched control group prior to exercise for both sexes. Immediately following damaging exercise, strength was decreased in both groups but there was a moderate effect size for lower strength during recovery in the T1D group at both 48-hours and 96-hours. Serum creatine kinase, an indicator of muscle damage, was moderately higher in T1D participants compared to controls at rest, and exhibited a small elevation 96-hours after exercise. Immunofluorescence analyses showed satellite cell content was lower at all timepoints in those with type 1 diabetes. T1D participants demonstrated a moderate delay in satellite cell proliferation (as assessed by Pax7+/Ki67+ nuclei counts) after exercise, reaching peak levels of proliferation 48-hours after control participants. Despite these differences, those with T1D did not exhibit greater ultrastructural muscle damage than controls as assessed by electron microscopy. Finally, a transcriptomic investigation of T1D muscle revealed several networks of dysregulated genes involving RNA translation as well as mitochondrial respiration function, providing potential explanations for previous observations of mitochondrial dysfunction in similar T1D cohorts. Our novel findings indicate that skeletal muscle from physically active, young adults with moderately controlled T1D may have a reduced ability to handle, and repair from, damaging exercise. While larger cohort studies are clearly needed, these results suggest that those with T1D may require longer recovery times following damaging exercise.
Project description:IntroductionClinician-led diabetes education is a fundamental component of care to assist people with Type 1 diabetes (T1D) self-manage their disease. Recent initiatives to incorporate a more patient-centered approach to diabetes education have included recommendations to make such education more individualized. Yet there is a dearth of research that identifies patients' perceptions of clinician-led diabetes education. We aimed to describe the experience of diabetes education from the perspective of young adults with T1D.MethodsWe designed a self-reported survey for Australian adults, aged 18-35 years, with T1D. Participants (n = 150) were recruited by advertisements through diabetes consumer-organizations. Respondents were asked to rate aspects of clinician-led diabetes education and identify sources of self-education. To expand on the results of the survey we interviewed 33 respondents in focus groups.ResultsSurveyThe majority of respondents (56.0%) were satisfied with the amount of continuing clinician-led diabetes education; 96.7% sought further self-education; 73.3% sourced more diabetes education themselves than that provided by their clinicians; 80.7% referred to diabetes organization websites for further education; and 30.0% used online chat-rooms and blogs for education. Focus groups: The three key themes that emerged from the interview data were deficiencies related to the pedagogy of diabetes education; knowledge deficiencies arising from the gap between theoretical diabetes education and practical reality; and the need for and problems associated with autonomous and peer-led diabetes education.ConclusionOur findings indicate that there are opportunities to improve clinician led-diabetes education to improve patient outcomes by enhancing autonomous health-literacy skills and to incorporate peer-led diabetes education and support with clinician-led education. The results provide evidence for the potential value of patient engagement in quality improvement and health-service redesign.
Project description:BACKGROUNDIn type 1 diabetes (T1D), impaired insulin sensitivity may contribute to the development of diabetic kidney disease (DKD) through alterations in kidney oxidative metabolism.METHODSYoung adults with T1D (n = 30) and healthy controls (HCs) (n = 20) underwent hyperinsulinemic-euglycemic clamp studies, MRI, 11C-acetate PET, kidney biopsies, single-cell RNA-Seq, and spatial metabolomics to assess this relationship.RESULTSParticipants with T1D had significantly higher glomerular basement membrane (GBM) thickness compared with HCs. T1D participants exhibited lower insulin sensitivity and cortical oxidative metabolism, correlating with higher insulin sensitivity. Proximal tubular transcripts of TCA cycle and oxidative phosphorylation enzymes were lower in T1D. Spatial metabolomics showed reductions in tubular TCA cycle intermediates, indicating mitochondrial dysfunction. The Slingshot algorithm identified a lineage of proximal tubular cells progressing from stable to adaptive/maladaptive subtypes, using pseudotime trajectory analysis, which computationally orders cells along a continuum of states. This analysis revealed distinct distribution patterns between T1D and HCs, with attenuated oxidative metabolism in T1D attributed to a greater proportion of adaptive/maladaptive subtypes with low expression of TCA cycle and oxidative phosphorylation transcripts. Pseudotime progression associated with higher HbA1c, BMI, and GBM, and lower insulin sensitivity and cortical oxidative metabolism.CONCLUSIONThese early structural and metabolic changes in T1D kidneys may precede clinical DKD.TRIAL REGISTRATIONClinicalTrials.gov NCT04074668.FUNDINGUniversity of Michigan O'Brien Kidney Translational Core Center grant (P30 DK081943); CROCODILE studies by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (P30 DK116073), Juvenile Diabetes Research Foundation (JDRF) (2-SRA-2019-845-S-B), Boettcher Foundation, Intramural Research Program at NIDDK and Centers for Disease Control and Prevention (CKD Initiative) under Inter-Agency Agreement #21FED2100157DPG.
Project description:ObjectiveTo assess the prevalence of high diabetes distress and associated factors in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY2) study cohort of young adults with youth-onset type 2 diabetes.Research design and methodsParticipants completed the Diabetes Distress Scale (DDS) at end-of-study visits. Factors examined for association with high distress were demographic (sex, race/ethnicity, age, education, income), medical (HbA1c, BMI, complications), psychological (depressive and anxiety symptoms), and social (number in household, offspring, health care coverage, established with diabetes care provider). Univariate logistic regression identified factors associated with high distress that were controlled for in multivariate logistic regressions.ResultsOf 438 participants, 66% were female (mean age 26.8 years, 18% non-Hispanic White, 37% non-Hispanic Black, 38% Hispanic). High distress (DDS ≥2) was reported by 105 (24%) participants. Subscales identified 40% with high regimen distress and 29.7% with high emotional burden. A greater percentage of those with high distress were female (P = 0.002), diagnosed with hypertension (P = 0.037) and retinopathy (P = 0.005), treated with insulin, had higher HbA1c, and had moderate to severe depressive and anxiety symptoms (all P < 0.001). In multivariate analyses, female sex (P < 0.001), HbA1c (P < 0.001), anxiety symptoms (P = 0.036), and lack of health care coverage (P = 0.019) were associated with high distress, after controlling for potential confounders. Moderate to severe depressive symptoms were associated with high regimen distress (P = 0.018) and emotional burden (P < 0.001); insulin treatment was associated with high emotional burden (P = 0.027).ConclusionsFuture research should identify modifiable factors associated with high diabetes distress in young adults with youth-onset type 2 diabetes that may inform distress interventions with this medically vulnerable group.
Project description:BackgroundThe transition of young adults with type 1 diabetes (T1D) from pediatric to adult care is challenging and frequently accompanied by worsening of diabetes-related health. To date, there are no reports which prospectively assess the effects of theory-based psycho-behavioral interventions during the transition period neither on glycemic control nor on psychosocial factors that contribute to poor glycemic control. Therefore, the overall aim of this study was to develop and pilot test an integrative group intervention based on the underlying principles of self-determination theory (SDT), in young adults with T1D.MethodsFifty-one young adults with T1D participated in an education and case management-based transition program, of which 9 took part in the Diabetes Empowerment Council (DEC), a 12-week holistic, multimodality facilitated group intervention consisting of "council" process based on indigenous community practices, stress-reduction guided imagery, narrative medicine modalities, simple ritual, and other integrative modalities. Feasibility, acceptability, potential mechanism of effects, and bio-behavioral outcomes were determined using mixed qualitative and quantitative methods.ResultsThe intervention was highly acceptable to participants, though presented significant feasibility challenges. Participants in DEC showed significant reductions in perceived stress and depression, and increases in general well-being relative to other control participants. Reduction in perceived stress, independent of intervention group, was associated with reductions in hemoglobin A1C. A theoretical model explaining the effects of the intervention included the promotion of relatedness and autonomy support, 2 important aspects of SDT.ConclusionsThe DEC is a promising group intervention for young adults with T1D going through transition to adult care. Future investigations will be necessary to resolve feasibility issues, optimize the multimodality intervention, determine full intervention effects, and fully test the role of the underlying theoretical model of action.ClinicalTrials.gov Registration Number NCT02807155; Registration date: June 15, 2016 (retrospectively registered).