Pernille M. Hansen

Effect of low-dose heparin on urinary albumin excretion in insulin-dependent diabetes mellitus

We investigated the effect of heparin on urinary albumin excretion in patients with insulin-dependent diabetes mellitus. 39 patients with persistent urinary albumin excretion of 30-300 mg/24 h were randomly treated for 3 months with subcutaneous injections twice daily of isotonic saline, 5000 IU unfractionated heparin, or 2000 anti-Xa IU low-molecular-weight heparin. Unfractionated and low-molecular-weight heparin induced a significant reduction in urinary albumin excretion (p = 0.04 and p = 0.004). The mechanism and clinical relevance is unknown but deserve further attention.

Genetic variation of the heparan sulfate proteoglycan gene (perlecan gene). Association with urinary albumin excretion in IDDM patients.

Both in patients with IDDM (1) and in healthy control subjects (2,3), increased urinary albumin excretion rate (AER) is associated with high relative morbidity and mortality. In IDDM patients, genetic susceptibility factors are most likely contributing to an increased AER (4,5) resulting in a cumulative incidence of nephropathy (AER >300 mg/24 h) of -30% (6). So far, candidate genes, proposed as susceptibility markers linked to abnormal albuminuria, have been identified because of the knowledge of pathophysiological events related to diabetic nephropathy. Heparan sulfate proteoglycan (HSPG, i.e., Perlecan) constitutes an integrated part of the glomerular basement membrane. It consists of a central core protein to which anionie sulfated polysaccharide chains (heparan sulfate [HS]) are linked (7), thus contributing to the negative charge of the glomerular filtration barrier and thereby indirectly to the composition of the glomerular filtration product (8,9). In IDDM patients, it has been demonstrated that increased AER is reduced by the administration of heparin (10) most likely because of a stimulating effect on the HS synthesis (11).

Polymorphisms in the Interleukin-1 Gene Cluster Do Not Contribute to the Genetic Susceptibility of Diabetic Nephropathy in Caucasian Patients With IDDM

Glomerular basement membrane thickening and increased accumulation of extracellular matrix are predominant features of the expanding mesangium in diabetic glomerulosclerosis (1). Interleukin-1 (IL-1) stimulates mesangial cell proliferation and extracellular matrix production (2). IL-lRa is a natural endogenous inhibitor that binds to the IL-1 receptor (IL-1RI) with equal affinity as IL-1, but without activating the cell. In streptozotocin-induced diabetic rats, shear-stress induced by glomerular hyperperfusion affects the mesangial cell phenotype, manifesting in increased transcription, translation, and secretion of IL-ip (3). Therefore, the genes in the IL-1 gene cluster can be considered as candidate genes for diabetic nephropathy. Polymorphisms in the genes coding for IL-ip (4) and IL-lRa (5,6) are involved in regulation of the function of IL-1. Recently, a study of a small and heterogeneous group of IDDM and NIDDM patients suggested the penta-allelic insertion polymorphism in the gene coding for IL-lRa as a risk marker for diabetic nephropathy (7). We studied the relationship among polymorphisms in the genes coding for IL-1 (3, IL-lRa, and IL-1RI (the IL-1 gene cluster) in IDDM patients with and without diabetic nephropathy. The patients participating in this study have been described in detail previously (8). Lymphocytes were isolated from peripheral blood, and DNA was prepared by standard techniques. A Taq I restriction fragment-length polymorphism of the IL-1B locus comprising polymorphic fragments of 13.4 kb (B*l allele) and 9.4 kb (B*2 allele) was identified by polymerase chain reaction (PCR) (4). An 86-bp tandem repeat of the second intron of the IL-lRa gene was characterized by PCR amplification and alleles termed Ax to A

Safety and Efficacy of Liraglutide in Patients With Type 2 Diabetes and End-Stage Renal Disease: An Investigator-Initiated, Placebo-Controlled, Double-Blind, Parallel-Group, Randomized Trial.

(9). In the IL1RI gene, a PCR and subsequent Pst I digestion resulted in a fragment of 362 bp (3.2 allele) or fragments of 256 and 108 bp

Possible effect of angiotensin-converting enzyme inhibition on glomerular charge selectivity

OBJECTIVE To evaluate parameters related to safety and efficacy of liraglutide in patients with type 2 diabetes and dialysis-dependent end-stage renal disease (ESRD). RESEARCH DESIGN AND METHODS Twenty-four patients with type 2 diabetes and ESRD and 23 control subjects with type 2 diabetes and normal kidney function were randomly allocated to 12 weeks of double-blind liraglutide (titrated to a maximum dose of 1.8 mg) or placebo treatment (1:1) injected subcutaneously once daily as add on to ongoing antidiabetic treatment. Dose-corrected plasma trough liraglutide concentration was evaluated at the final trial visit as the primary outcome measure using a linear mixed model. RESULTS Twenty patients with ESRD (1:1 for liraglutide vs. placebo) and 20 control subjects (1:1) completed the study period. Dose-corrected plasma trough liraglutide concentration at the final visit was increased by 49% (95% CI 6–109, P = 0.02) in the group with ESRD compared with the control group. Initial and temporary nausea and vomiting occurred more frequently among liraglutide-treated patients with ESRD compared with control subjects (P < 0.04). Glycemic control tended to improve during the study period in both liraglutide-treated groups as assessed by daily blood glucose measurements (P < 0.01), and dose of baseline insulin was reduced in parallel (P < 0.04). Body weight was reduced in both liraglutide-treated groups (−2.4 ± 0.8 kg [mean ± SE] in the group with ESRD, P = 0.22; −2.9 ± 1.0 kg in the control group, P = 0.03). CONCLUSIONS Plasma liraglutide concentrations increased during treatment in patients with type 2 diabetes and ESRD, who experienced more gastrointestinal side effects. Reduced treatment doses and prolonged titration period may be advisable.

Safety and efficacy of liraglutide in patients with type 2 diabetes and end-stage renal disease: protocol for an investigator-initiated prospective, randomised, placebo-controlled, double-blinded, parallel intervention study

Angiotensin-converting enzyme (ACE) inhibitors are known to reduce urinary albumin excretion (UAE) in diabetic patients. Animal studies have shown that, besides diminishing the glomerular capillary pressure, ACE inhibitors might reduce albuminuria by influencing glomerular charge selectivity through glomerular preservation of heparan sulphate proteoglycan. In humans, an indirect measurement of glomerular charge selectivity can be obtained by calculating the glomerular charge selectivity index (SI), a clearance ratio of IgG/IgG4, two identically sized but differently charged molecules. The aim of the present study was to evaluate the effect of ACE inhibition on charge selectivity by comparing SI in type I (insulin-dependent) diabetic patients with microalbuminuria after 6 years of treatment either with or without captopril. Thirty-five of 45 patients participating in a prospective randomized study evaluating the effect of captopril in preventing the development of diabetic nephropathy were included in the present study, 17 being treated with captopril, 18 left as untreated controls. The selectivity index was calculated after measuring s-IgG, u-IgG, s-IgG4, and u-IgG4. The results demonstrated a higher selectivity index in the captopril-treated group [1.21 (0.51-1.94) median (range)] compared to the control group [0.94 (0.31-1.87)], however, the difference was not statistically significant (p = 0.16). A negative correlation between the selectivity index and UAE was demonstrated in the captopril-treated group (r = -0.77; p = 0.0004), whereas the correlation in the control group did not reach statistical significance (r = -0.3; p = 0.2).(ABSTRACT TRUNCATED AT 250 WORDS)

Genetic variation of a collagen IV α1-chain gene polymorphism in Danish insulin-dependent diabetes mellitus (IDDM) patients: Lack of association to nephropathy and proliferative retinopathy

Introduction Diabetes is the leading cause of end-stage renal disease (ESRD). Owing to renal clearance, several antidiabetic agents cannot be used in patients with ESRD. The present protocol describes an investigator-initiated trial aiming to test safety and efficacy of treatment with the glucagon-like peptide-1 receptor agonist liraglutide in patients with type 2 diabetes and dialysis-dependent ESRD. Methods and analysis Twenty patients with type 2 diabetes and ESRD will be compared with 20 matched patients with type 2 diabetes and normal kidney function in a randomised, parallel, placebo-controlled (1 : 1), double-blinded setting. All participants will receive 12 weeks of daily treatment with liraglutide/placebo in an individually titrated dose of 0.6, 1.2 or 1.8 mg. Over nine visits, plasma liraglutide, glycaemic control, β-cell response, cardiovascular parameters, various biomarkers and adverse events will be assessed. The primary endpoint will be evaluated from dose-corrected plasma trough liraglutide concentration at the final trial visit to determine potential accumulation in the ESRD group. Ethics and dissemination The study has been approved by the Danish Medicines Agency, the Scientific-Ethical Committee of the Capital Region of Denmark and the Danish Data Protection Agency. An external monitoring committee (The Good Clinical Practice Unit at Copenhagen University Hospitals) will oversee the study. The results of the study will be presented at national and international scientific meetings, and publications will be submitted to peer-reviewed journals. Trial registration ClinicalTrials.gov Identifier: NCT01394341

Skeletal muscle lipoprotein-lipase activity in insulin-dependent diabetic patients with and without albuminuria

In insulin‐dependent (Type 1) diabetes mellitus (IDDM) the development of nephropathy is partly due to genetic susceptibility. Previously one study has demonstrated a relationship between a HindIII restriction polymorphism of the collagen IV α1‐chain gene and diabetic nephropathy. The aim of the present study was to evaluate such as association in a case–control study including 207 Danish IDDM patients: 116 with nephropathy (urinary albumin excretion rate (AER) > 300 mg 24 h−1) and 91 without nephropathy (AER < 30 mg 24 h−1). Using genomic DNA, HindIII restriction fragment length analysis revealed a bi allele polymorphism visualized by Southern hybridization with a cDNA probe recognizing the collagen IV α1‐chain gene. No differences in genotype frequencies or allele frequencies were demonstrated comparing patients with and without nephropathy: p = 0.39 and p = 0.96, respectively. Neither were there any difference in genotype frequencies or allele frequencies when the patients were stratified according to the presence of proliferative retinopathy: p = 0.44 and p = 0.84, respectively. Pooling the diabetic groups revealed genotype frequencies and allele frequencies comparable to those found in 57 healthy unrelated Danish individuals. We conclude that in a Danish IDDM population a HindIII restriction polymorphism of the collagen IV α1‐chain gene is not associated with diabetic nephropathy, diabetic retinopathy or with diabetes per se.

Characterization of polymorphisms of an interleukin 1 receptor type 1 gene (IL1RI) promotor region (P2) and their relation to Insulin-Dependent Diabetes Mellitus (IDDM)

In patients with insulin-dependent diabetes mellitus (IDDM), albuminuria reflects widespread vascular dysfunction. Albuminuria has been associated to defects of heparan sulfate proteoglycan (HSPG) within the extracellular matrix. Our hypothesis is that loss of HSPG in vascular walls reduces the HSPG-bound lipoprotein-lipase activity (LPLA), thereby causing elevated levels of plasma triglyceride (TG) seen in IDDM patients with albuminuria. The aim of the present study was to evaluate whether LPLA in muscle capillaries could be related to TG in IDDM patients with and without albuminuria. This is a cross-sectional study including ten healthy control subjects (group C), nine patients with IDDM and urinary albumin excretion rate (AER) of 30 mg/24 h or less (group D0) and 20 patients with IDDM and AER greater than 30 mg/24 h (group DA). Muscle LPLA, plasma TG, total cholesterol, high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), and very-low-density lipoprotein cholesterol (VLDL) were measured. Between groups no difference in total cholesterol, TG, VLDL, and LDL was found. In patients with albuminuria, LPLA was reduced compared to controls, however, the difference between the groups was not statistically significant [median (range)] 35.9 mU/g (20.4-103) versus 44.6 mU/g (28.2-57.2) and 40.9 mU/g (21.7-53.5) in group DA, C, and D0, respectively, p = 0.76. AER was not correlated to LPLA. An overall negative correlation between TG and LPLA was found; r = -0.33, p = 0.04, supported by an overall significant positive correlation between LPLA and HDL; r = 0.32, p = 0.045. We conclude that, in insulin-dependent diabetes mellitus, skeletal muscle lipoprotein-lipase activity is associated with plasma triglyceride, while an association between lipoprotein-lipase activity and urinary albumin excretion is questionable.