Addition of insulin glargine or NPH insulin to metformin monotherapy in poorly controlled type 2 diabetic patients decreases IGF-I bioactivity similarly

Aims/hypothesis The aim of this study was to compare IGFI bioactivity 36 weeks after the addition of insulin glargine (A21Gly,B31Arg,B32Arg human insulin) or NPH insulin to metformin therapy in type 2 diabetic patients who had poor glucose control under metformin monotherapy. Methods In the Lantus plus Metformin (LANMET) study, 110 poorly controlled insulin-naive type 2 diabetic patients were randomised to receive metformin with either insulin glargine (G+MET) or NPH insulin (NPH+MET). In the present study, IGF-I bioactivity was measured, retrospectively, in 104 out of the 110 initially included LANMET participants before and after 36 weeks of insulin therapy. IGF-I bioactivity was measured using an IGF-I kinase receptor activation assay. Results After 36 weeks of insulin therapy, insulin doses were comparable between the G+MET (68±5.7 U/day) and NPH+MET (71±6.2 U/day) groups (p=0.68). Before insulin therapy, circulating IGF-I bioactivity was similar between the G+MET (134±9 pmol/l) and NPH+MET (135 ±10 pmol/l) groups (p=0.83). After 36 weeks, IGF-I bioactivity had decreased significantly (p=0.001) and did not differ between the G+MET (116±9 pmol/l) and NPH+MET (117± 10 pmol/l) groups (p=0.91). At baseline and after insulin therapy, total IGF-I concentrations were comparable in both groups (baseline: G+MET 13.3±1.0 vs NPH+MET 13.3± 1.0 nmol/l, p=0.97; and 36 weeks: 13.4±1.0 vs 13.1± 0.9 nmol/l, p=0.71). Total IGF-I concentration did not change during insulin therapy (13.3±0.7 vs 13.3±0.7 nmol/l, baseline vs 36 weeks, p=0.86). Conclusions/interpretation Addition of insulin glargine or NPH insulin to metformin monotherapy in poorly controlled type 2 diabetic patients decreases serum IGF-I bioactivity in a similar manner

Selenium status is positively associated with bone mineral density in healthy aging European men

Objective It is still a matter of debate if subtle changes in selenium (Se) status affect thyroid function tests (TFTs) and bone mineral density (BMD). This is particularly relevant for the elderly, whose nutritional status is more vulnerable. Design and Methods We investigated Se status in a cohort of 387 healthy elderly men (median age 77 yrs; inter quartile range 75-80 yrs) in relation to TFTs and BMD. Se status was determined by measuring both plasma selenoprotein P (SePP) and Se. Results The overall Se status in our population was low normal with only 0.5% (2/387) of subjects meeting the criteria for Se deficiency. SePP and Se levels were not associated with thyroid stimulating hormone (TSH), free thyroxine (FT4), thyroxine (T4), triiodothyronine (T3) or reverse triiodothyronine (rT3) levels. The T3/T4 and T3/rT3 ratios, reflecting peripheral metabolism of thyroid hormone, were not associated with Se status either. SePP and Se were positively associated with total BMD and femoral trochanter BMD. Se, but not SePP, was positively associated with femoral neck and ward's BMD. Multivariate linear analyses showed that these associations remain statistically significant in a model including TSH, FT4, body mass index, physical performance score, age, smoking, diabetes mellitus and number of medication use. Conclusion Our study demonstrates that Se status, within the normal European marginally supplied range, is positively associated with BMD in healthy aging men, independent of thyroid function. Thyroid function tests appear unaffected by Se status in this population

Pharmacogenetics of ACE inhibition in stable coronary artery disease: steps towards tailored drugs therapy

Purpose of review Several trials demonstrated that angiotensin-converting enzyme inhibitors reduce the incidence of cardiovascular events during long-term follow-up in high-risk and low-risk patients. Clinical treatment guidelines propose that angiotensin-converting enzyme inhibitors should be considered in the routine secondary prevention in the broad group of coronary artery disease patients. This review discusses several approaches to guide angiotensin-converting enzyme-inhibition therapy to more specific groups of patients that are most likely to benefit. Recent findings The beneficial effect of angiotensin-converting enzyme inhibition has been shown to be consistent across subgroups in stable coronary artery disease. Still, large interindividual variability in blood pressure response is well documented. It should also be realized that the absolute treatment effects are modest. The efficiency and cost-effectiveness of this prolonged prophylactic treatment would be significantly enhanced if those patients can be distinguished who benefit most. Recently, it was suggested that markers of an activated renin–angiotensin–aldosterone system might be used to guide angiotensinconverting enzyme-inhibition therapy. Summary At the start of treatment, clinical characteristics are not sufficient to distinguish between patients who will and will not benefit from angiotensin-converting enzyme inhibitors. Although pharmacogenetic research in coronary artery disease is still in a premature stage, it may be expected to provide a useful tool in optimizing and individualizing the management of angiotensin-converting enzyme-inhibitor therapy in coronary artery disease patients

Revisiting the role of insulin-like growth factor-I receptor stimulating activity and the apolipoprotein E in Alzheimer’s disease

Background: Alterations in insulin-like growth factor I (IGF-I) signaling have been associated with dementia and Alzheimer's disease (AD). Studies on the association between IGF-I levels and dementia risk have been inconclusive. We reported earlier that higher levels of IGF-I receptor stimulating activity are associated with a higher prevalence and incidence of dementia. Objective: In the present study, we test the robustness of the association between IGF-I receptor stimulating activity and dementia by extending the follow-up period to 16 years and investigate possible effect modification by apolipoprotein E (ApoE). Methods: At baseline, circulating IGF-I receptor stimulating activity was determined by the IGF-I kinase receptor activation (KIRA) assay in 1,014 elderly from the Rotterdam Study. Dementia was assessed from baseline (1997-1999) to follow-up in January 2015. Associations of IGF-I receptor stimulating activity and incident dementia were assessed with Cox proportional hazards models. Results: During 10,752 person-years of follow-up, 174 people developed dementia. In the extended follow-up we no longer observed a dose-response relationship between IGF-I receptor stimulating activity and risk of dementia [adjusted odds ratio 1.11; 95% confidence interval (CI) 0.97-1.28]. Interestingly, we found evidence of an interaction between ApoE-ε4 and tertiles of IGF-I receptor stimulating activity. IGF-I receptor stimulating activity in the median and top tertiles was related to increased dementia incidence in hetero- and homozygotes of the ApoE-ε4 allele, but did not show any association with dementia risk in people without the ApoE-ε4 allele (adjusted odds ratio medium vs. low IGF-I receptor stimulating activity in ApoE-ε4 carriers: 1.45; 95% CI 1.00-2.12). These findings suggest a threshold effect in ApoE-ε4 carriers. In line with the hypothesis that downregulation of IGF-I signaling is associated with increased dementia risk, ApoE-ε4 homozygotes without prevalent dementia displayed lower levels of IGF-I receptor stimulating activity than heterozygotes and non-carriers. Conclusion: The findings shed new light on the association between IGF-I signaling and the neuropathology of dementia and ask for replication in other cohorts, using measures of IGF-I receptor stimulating activity rather than total serum levels as putative markers of dementia risk

Genetic determinants of treatment benefit of the angiotensin-converting enzyme-inhibitor perindopril in patients with stable coronary artery disease.

AIMS: The efficacy of angiotensin-converting enzyme (ACE)-inhibitors in stable coronary artery disease (CAD) may be increased by targeting the therapy to those patients most likely to benefit. However, these patients cannot be identified by clinical characteristics. We developed a genetic profile to predict the treatment benefit of ACE-inhibitors exist and to optimize therapy with ACE-inhibitors. METHODS AND RESULTS: In 8907 stable CAD patients participating in the randomized placebo-controlled EUROPA-trial, we analysed 12 candidate genes within the pharmacodynamic pathway of ACE-inhibitors, using 52 haplotype-tagging-single nucleotide polymorphisms (SNPs). The primary outcome was the reduction in cardiovascular mortality, non-fatal myocardial infarction, and resuscitated cardiac arrest during 4.2 years of follow-up. Multivariate Cox regression was performed with multiple testing corrections using permutation analysis. Three polymorphisms, located in the angiotensin-II type I receptor and bradykinin type I receptor genes, were significantly associated with the treatment benefit of perindopril after multivariate adjustment for confounders and correction for multiple testing. A pharmacogenetic score, combining these three SNPs, demonstrated a stepwise reduction of risk in the placebo group and a stepwise decrease in treatment benefit of perindopril with an increasing scores (interaction P < 0.0001). A pronounced treatment benefit was observed in a subgroup of 73.5% of the patients [hazard ratio (HR) 0.67; 95% confidence interval (CI) 0.56-0.79], whereas no benefit was apparent in the remaining 26.5% (HR 1.26; 95% CI 0.97-1.67) with a trend towards a harmful effect. In 1051 patients with cerebrovascular disease from the PROGRESS-trial, treated with perindopril or placebo, an interaction effect of similar direction and magnitude, although not statistically significant, was observed. CONCLUSION: The current study is the first to identify genetic determinants of treatment benefit of ACE-inhibitor therapy. We developed a genetic profile which predicts the treatment benefit of ACE-inhibitors and which could be used to optimize therapy