Lipoprotein(a) plasma levels are not associated with incident microvascular complications in type 2 diabetes mellitus

Aims/hypothesis: Microvascular disease in type 2 diabetes is a significant cause of end-stage renal disease, blindness and peripheral neuropathy. The strict control of known risk factors, e.g. lifestyle, hyperglycaemia, hypertension and dyslipidaemia, reduces the incidence of microvascular complications, but a residual risk remains. Lipoprotein (a) [Lp(a)] is a strong risk factor for macrovascular disease in the general population. We hypothesised that plasma Lp(a) levels and the LPA gene SNPs rs10455872 and rs3798220 are associated with the incident development of microvascular complications in type 2 diabetes. Methods: Analyses were performed of data from the DiaGene study, a prospective study for complications of type 2 diabetes, collected in the city of Eindhoven, the Netherlands (n = 1886 individuals with type 2 diabetes, mean follow-up time = 6.97 years). To assess the relationship between plasma Lp(a) levels and the LPA SNPs with each newly developed microvascular complication (retinopathy n = 223, nephropathy n = 246, neuropathy n = 236), Cox proportional hazards models were applied and adjusted for risk factors for microvascular complications (age, sex, mean arterial pressure, non-HDL-cholesterol, HDL-cholesterol, BMI, duration of type 2 diabetes, HbA1c and smoking). Results: No significant associations of Lp(a) plasma levels and the LPA SNPs rs10455872 and rs3798220 with prevalent or incident microvascular complications in type 2 diabetes were found. In line with previous observations the LPA SNPs rs10455872 and rs3798220 did influence the plasma Lp(a) levels. Conclusions/interpretation: Our data show no association between Lp(a) plasma levels and the LPA SNPs with known effect on Lp(a) plasma levels with the development of microvascular complications in type 2 diabetes. This indicates that Lp(a) does not play a major role in the development of microvascular complications. However, larger studies are needed to exclude minimal effects of Lp(a) on the development of microvascular complications

Use of monomeric and oligomeric flavanols in the dietary management of patients with type 2 diabetes mellitus and microalb

__Background:__ Patients with type 2 diabetes mellitus (T2D) are prone to micro- and macro-vascular complications. Monomeric and oligomeric flavanols (MOF) isolated from grape seeds (Vitis vinifera) have been linked to improved endothelial function and vascular health. The aim of this study is to determine the effect of a daily supplementation of 200 mg MOF on renal endothelial function of patients with T2D and microalbuminuria. __Methods/design:__ For this double-blind, placebo-controlled, randomized, multicenter trial 96 individuals (ages 40-85 years) with T2D and microalbuminuria will be recruited. Participants will be randomly assigned to the intervention group, receiving 200 mg of MOF daily for 3 months, or to the control group, receiving a placebo. The primary endpoint is the evolution over time in albumin excretion rate (AER) until 3 months of intervention as compared with placebo. Secondary endpoints are the evolution over time in established plasma markers of renal endothelial function-asymmetric dimethylarginine (ADMA), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular cell adhesion molecule-1 (sICAM-1), interleukin-6 (IL-6), and von Willebrand Factor (vWF)-until 3 months of intervention as compared with placebo. Mixed modeling will be applied for the statistical analysis of the data. __Discussion:__ We hypothesize that T2D patients with microalbuminuria have a medically determined requirement for MOF and that fulfilling this requirement will result in a decrease in AER and related endothelial biomarkers. If confirmed, this may lead to new insights in the dietary management of patients with T2D

HDL associates with insulin resistance and beta-cell dysfunction in South Asian families at risk of type 2 diabetes

Objective: Dyslipidemia precedes type 2 diabetes (T2D) and worsens with increasing glucose intolerance. First degree relatives of T2D patients have an increased risk to develop dyslipidemia and glucose intolerance. The aim of the present study was to assess the relation between the development of dyslipidemia and glucose intolerance in first-degree relatives of T2D patients. Research design and methods: Fasting lipoprotein profiles were determined by density gradient ultracentrifugation in T2D patients and their first-degree relatives (42 Caucasians and 33 South Asians), and in 29 normoglycemic controls from non-T2D families. Glucose tolerance, insulin sensitivity index (ISI) and insulin disposition index (DI) were assessed by an extended, frequently sampled oral glucose tolerance test (OGTT), and fractional insulin synthesis rate (FSR) was measured by 13C-leucine enrichment in urinary C-peptide during the OGTT. Results: Of the first-degree relatives, 40, 16 and 19 had NGT, prediabetes and T2D, respectively. NGT family members had lower plasma HDL-cholesterol (HDL[sbnd]C) (1.34 ± 0.07 vs 1.58 ± 0.06 mmol/L; p = 0.015), HDL2-C (0.41 ± 0.05 vs 0.57 ± 0.05 mmol/L; p = 0.021) and HDL3-C (0.62 ± 0.03 vs 0.72 ± 0.02 mmol/L; p = 0.043) than controls. HDL2-C levels tended to decrease with increasing glucose intolerance state. In South Asians, buoyant LDL-C levels decreased with increasing glucose intolerance state (p = 0.006). In South Asian families, HDL-C correlated with both ISI and DI (β 0.42; p = 0.04 and β 0.53; p = 0.01, respectively), whereas HDL2-C and HDL3-C levels correlated with DI (β 0.64; p = 0.002 and β 0.57; p = 0.005, respectively). HDL2-C and plasma triglyceride correlated with FSR (β 0.48; p = 0.033 and β −0.50; p = 0.029, respectively). Conclusions: Low HDL2-C and HDL3-C levels are present in NGT first-degree relatives of T2D patients, and HDL2-C tend to decrease further with increasing glucose intolerance. In South Asian families HDL2-C and HDL3-C levels linked predominantly to deteriorating beta cell function.</p

Use of monomeric and oligomeric flavanols in the dietary management of patients with type 2 diabetes mellitus and microalbuminuria (FLAVA trial): study protocol for a randomized controlled trial

Abstract Background Patients with type 2 diabetes mellitus (T2D) are prone to micro- and macro-vascular complications. Monomeric and oligomeric flavanols (MOF) isolated from grape seeds (Vitis vinifera) have been linked to improved endothelial function and vascular health. The aim of this study is to determine the effect of a daily supplementation of 200 mg MOF on renal endothelial function of patients with T2D and microalbuminuria. Methods/design For this double-blind, placebo-controlled, randomized, multicenter trial 96 individuals (ages 40–85 years) with T2D and microalbuminuria will be recruited. Participants will be randomly assigned to the intervention group, receiving 200 mg of MOF daily for 3 months, or to the control group, receiving a placebo. The primary endpoint is the evolution over time in albumin excretion rate (AER) until 3 months of intervention as compared with placebo. Secondary endpoints are the evolution over time in established plasma markers of renal endothelial function—asymmetric dimethylarginine (ADMA), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular cell adhesion molecule-1 (sICAM-1), interleukin-6 (IL-6), and von Willebrand Factor (vWF)—until 3 months of intervention as compared with placebo. Mixed modeling will be applied for the statistical analysis of the data. Discussion We hypothesize that T2D patients with microalbuminuria have a medically determined requirement for MOF and that fulfilling this requirement will result in a decrease in AER and related endothelial biomarkers. If confirmed, this may lead to new insights in the dietary management of patients with T2D. Trial registration Nederlands Trial Register, NTR4669, registered on 7 July 2014

The effect of monomeric and oligomeric FLAVAnols in patients with type 2 diabetes and microalbuminuria (FLAVA-trial): A double-blind randomized controlled trial

Background &amp; aims: Microalbuminuria is an early sign of vascular complications of type 2 diabetes and predicts cardiovascular disease and mortality. Monomeric and oligomeric flavanols (MOFs) are linked to improved vascular health. The aim of this study was to assess the effect of 3 months MOFs on albuminuria and endothelial function markers in patients with type 2 diabetes and microalbuminuria. Methods: We conducted a double-blind, placebo-controlled trial among patients with type 2 diabetes and microalbuminuria. Patients with type 2 diabetes received either 200 mg MOFs or placebo daily on top of their habitual diet and medication. The primary endpoint was the between-group difference of the change in 24-h Albumin Excretion Rate (AER) over three months. Secondary endpoints were the between-group differences of the change in plasma levels of different markers of endothelial dysfunction. Mixed-modelling was applied for the longitudinal analyses. Results: Participants (n = 97) were 63.0 ± 9.5 years old; diabetes-duration was 15.7 ± 8.5 years. Median baseline AER was 60 (IQR 20–120) mg/24 h. There was no within-group difference in median change of AER from baseline to 3 months in the intervention (0 (-35-21) mg/24 h, p = 0.41) or the control group (0 (-20-10) mg/24 h, p = 0.91). There was no between-group difference in the course of AER over three months (log-transformed data: β = −0.02 (95%CI -0.23-0.20), p = 0.88), nor in the plasma levels of the endothelial dysfunction markers. Conclusion: Daily 200 mg MOFs for three months on top of habitual diet and usual care did not reduce AER and plasma markers of endothelial dysfunction compared to placebo, in patients with long-term type 2 diabetes and microalbuminuria. Clinical trials registration: NTR4669, www.trialregister.nl.</p