M. K. Svensson

Assessment of beta-cell function in young patients with type 2 diabetes: arginine-stimulated insulin secretion may reflect beta-cell reserve

Simple methods for the evaluation of dynamic β‐cell function in epidemiological and clinical studies of patients with type 2 diabetes (T2D) are needed. The aim of this study was to evaluate the dynamic beta‐cell function in young patients with T2D with different disease durations and treatments.

Role of cannabinoid receptor 1 in human adipose tissue for lipolysis regulation and insulin resistance

We recently showed that the peripheral cannabinoid receptor type 1 (CNR1) gene is upregulated by the synthetic glucocorticoid dexamethasone. CNR1 is highly expressed in the central nervous system and has been a drug target for the treatment of obesity. Here we explore the role of peripheral CNR1 in states of insulin resistance in human adipose tissue. Subcutaneous adipose tissue was obtained from well-controlled type 2 diabetes subjects and controls. Subcutaneous adipose tissue gene expression levels of CNR1 and endocannabinoid synthesizing and degrading enzymes were assessed. Furthermore, paired human subcutaneous adipose tissue and omental adipose tissue from non-diabetic volunteers undergoing kidney donation or bariatric surgery, was incubated with or without dexamethasone. Subcutaneous adipose tissue obtained from volunteers through needle biopsy was incubated with or without dexamethasone and in the presence or absence of the CNR1-specific antagonist AM281. CNR1 gene and protein expression, lipolysis and glucose uptake were evaluated. Subcutaneous adipose tissue CNR1 gene expression levels were 2-fold elevated in type 2 diabetes subjects compared with control subjects. Additionally, gene expression levels of CNR1 and endocannabinoid-regulating enzymes from both groups correlated with markers of insulin resistance. Dexamethasone increased CNR1 expression dose-dependently in subcutaneous adipose tissue and omental adipose tissue by up to 25-fold. Dexamethasone pre-treatment of subcutaneous adipose tissue increased lipolysis rate and reduced glucose uptake. Co-incubation with the CNR1 antagonist AM281 prevented the stimulatory effect on lipolysis, but had no effect on glucose uptake. CNR1 is upregulated in states of type 2 diabetes and insulin resistance. Furthermore, CNR1 is involved in glucocorticoid-regulated lipolysis. Peripheral CNR1 could be an interesting drug target in type 2 diabetes and dyslipidemia.

Overweight, hyperglycemia and tobacco use are modifiable risk factors for onset of retinopathy 9 and 17 years after the diagnosis of diabetes – A retrospective observational nation-wide cohort study

BACKGROUND The aims of this study were to estimate the risk for diabetic retinopathy (DR) and to identify risk factors. We investigated a nationwide population-based cohort with diabetes diagnosed at age 15-34years. PATIENTS AND METHODS Of 794 patients registered 1987-1988 in the Diabetes Incidence Study in Sweden (DISS) 444 (56%) patients with retinal photos available for classification of retinopathy participated in a follow-up study 15-19 (median 17) years after diagnosis. Mean age was 42.3±5.7years, BMI 26.1±4.1kg/m2, 62% were male and 91% had type 1 diabetes. A sub-study was performed in 367 patients with retinal photos from both the 9 and 17year follow up and the risk for development of retinopathy between 9 and 17years of follow up was calculated. RESULTS After median 17years 324/444 (73%, 67% of T1D and 71% of T2D), had developed any DR but only 5.4% proliferative DR. Male sex increased the risk of developing retinopathy (OR 1.9, 95% CI 1.2-2.9). In the sub-study obesity (OR 1.2, 95% CI 1.04-1.4), hyperglycemia (OR 2.5, 95% CI 1.6-3.8) and tobacco use (OR 2.9, 95% CI 1.1-7.3) predicted onset of retinopathy between 9 and 17years after diagnosis of diabetes. CONCLUSION The number of patients with severe retinopathy after 17years of diabetes disease was small. The risk of developing retinopathy with onset between 9 and 17years after diagnosis of diabetes was strongly associated to modifiable risk factors such as glycemic control, obesity and tobacco use.

Treatment target re-classification of subjects comparing estimation of low-density lipoprotein cholesterol by the Friedewald equation and direct measurement of LDL-cholesterol.

Abstract Aims: To compare low-density lipoprotein cholesterol (LDL-C) values calculated by the Friedewald equation with direct LDL-C in patient samples and assess the possible impact on re-classification of LDL-C target values for primary prevention or high cardiovascular disease (CVD) risk (<2.5 mmol/L) and secondary prevention or very high CVD risk (<1.8 mmol/L). LDL-C is an important CVD risk factor. Over the last decade, there has been a change in laboratory methodology from indirectly calculated LDL-C with the Friedewald equation to direct LDL-C measurements (dLDL-C). Methods: Reported results for plasma triglycerides, total cholesterol, high-density lipoprotein-cholesterol, and dLDL-C from 34,981 samples analyzed in year 2014 were extracted from the laboratory information system, Uppsala University Hospital, Uppsala, Sweden. Results: dLDL-C was approximately 10% lower than the corresponding LDL-C results calculated by the Friedewald equation in both men and women. In subjects with triglyceride concentrations above 4 mmol/L (n = 1250) the same discordant pattern was seen as for the entire study population. Altogether 5469 out of 18,051 men (30.3%) and 4604 out of 16,928 women (27.2%) were down-classified at least one CVD risk category. A very small number of subject was up-classified, in total 37 out of 18,051 men (0.2%) and 28 out of 16,928 women (0.2%). Conclusions: The two LDL-C methods had a high concordance, but the direct LDL-C measurement consistently gave approx. 10% lower values, and this caused one-third of subjects to be re-classified as having a lower cardiovascular disease risk in relation to recommended LDL-C target values and decision limits.

Reduced renal function in patients with Myotonic Dystrophy type 1 and the association to CTG expansion and other potential risk factors for chronic kidney disease

Myotonic dystrophy type 1 (DM1) affects several organs. Disease severity and age at onset are correlated to the CTG repeat expansion. The aim of this study was to assess renal function and the association to numbers of CTG repeat expansion in patients with DM1. Ninety-eight patients with DM1 were included. Glomerular filtration rate (measured GFR) was measured using iohexol clearance. Data on CTG repeats were available in 83/98 (85%) patients. The overall mGFR was 74 (16) ml/min/1.73 m2 (range 38-134). Sixty-four patients (69%) had a mild and sixteen patients (17%) a moderate decrease in renal function (mGFR 60-89 and 30-59 ml/min/1.73 m2, respectively). No correlations were found between CTG repeats and mGFR (r = 0.10, p = 0.4) or between CTG repeats and serum cystatin C (r = 0.12, p = 0.29). CTG repeats was positively correlated to creatinine-based estimates of GFR (eGFR) (modified diet in renal disease r = 0.49, p < 0.001, CKD-EPI creatinine equation; r = 0.50, p < 0.001), but analyses using Structural Equation Modeling showed no correlation. The correlation was explained by an indirect effect via serum creatinine and skeletal muscle mass index. In conclusion, patients with DM1 seem to have a slight decrease in renal function but there is no association between renal function and the number of CTG repeats, a marker of disease severity.

Markers of fibrinolysis may predict development of lower extremity arterial disease in patients with diabetes: A longitudinal prospective cohort study with 10 years of follow-up

Background: A previous cross-sectional study suggested that tissue plasminogen activator–activity might be an early marker of asymptomatic lower extremity arterial disease, but the long-term relationship is unknown. Subjects and methods: This study included 96 diabetic (48 type 1/48 type 2) and 62 non-diabetic subjects aged 30–70 years without previously known lower extremity arterial disease (age: 50.3 ± 9.3 years, gender: M/W 47.5/52.5% and body mass index: 26.6 ± 4.5 kg/m2). The relationships between asymptomatic lower extremity arterial disease and fibrinolytic markers (tissue plasminogen activator–activity, tissue plasminogen activator–mass, plasminogen activator inhibitor-1 activity) at baseline and after 10 years were assessed by logistic regression analysis adjusting for age, hypertension, statin treatment, HbA1c, triglycerides and low-density lipoprotein cholesterol as fixed covariates. Results: The tissue plasminogen activator–activity at baseline and at the 10-year follow-up significantly predicted the presence of sign(s) of lower extremity arterial disease (odds ratio = 1.78, 95% confidence interval: 1.02–3.10, p = 0.043 and odds ratio = 1.78, 95% confidence interval: 1.12–2.23, p = 0.014, respectively). In addition, tissue plasminogen activator–mass at the 10-year follow-up was associated with signs of lower extremity arterial disease (odds ratio = 1.07, 95% confidence interval: 1.00–1.15, p = 0.046). Baseline age, hypertension and HbA1c were independently associated with sign(s) of lower extremity arterial disease at 10 years (odds ratio = 1.09, 95% confidence interval: 1.04–1.14, p = < 0.001; odds ratio = 3.68, 95% confidence interval: 1.67–8.12, p = 0.001 and odds ratio = 1.54, 95% confidence interval: 1.21–1.95, p = < 0.001, respectively). Conclusion: This long-term study supports previous findings of a significant association between asymptomatic lower extremity arterial disease and tissue plasminogen activator–activity. Thus, tissue plasminogen activator–activity may be an early marker of lower extremity arterial disease although the mechanism of this relationship remains unclear.

Dynamic beta cell function in young type 2 diabetes patients (15-34 years) in the Diabetes Incidence Study in Sweden register

Background and aims: The association between type 2 diabetes and different forms of cognitive impairment is well established. The mechanism behind the association is however still unrevealed. We ha ...