Paraoxonase 1 phenotype distribution and activity differs in subjects with newly diagnosed Type 2 diabetes (the CODAM Study).

Aims: Paraoxonase 1 (PON1) is an antioxidant high-density lipoprotein-bound enzyme, which was recently found to be expressed in the islets of Langerhans. A substitution (Q/R) at position 192 results in enzymes with different activity. Oxidation has been implicated in the onset of diabetes, and it can be hypothesized that PON1 may have a protective effect on diabetes.

Genetic variation in thioredoxin interacting protein (TXNIP) is associated with hypertriglyceridaemia and blood pressure in diabetes mellitus.

Aims: Thioredoxin interacting protein (TXNIP) is an attractive candidate gene for diabetes or diabetic dyslipidaemia, since TXNIP is the strongest glucose-responsive gene in pancreatic B-cells, TXNIP deficiency in a mouse model is associated with hyperlipidaemia and TXNIP is located in the 1q21-1q23 chromosomal Type 2 diabetes mellitus (DM) locus. We set out to investigate whether metabolic effects of TXNIP that were previously reported in a murine model are also relevant in human Type 2 DM.

Methods: The frequency distribution of a 3' UTR single nucleotide polymorphism (SNP) in TXNIP was investigated in subjects with normal glucose tolerance (NGT; n = 379), impaired glucose tolerance (IGT; n = 228) and Type 2 DM (n = 230).

Direct association of a promoter polymorphism in the CD36/FAT fatty acid transporter gene with Type 2 diabetes mellitus and insulin resistance.

Aims: The membrane-bound fatty acid transporter CD36/FAT may play a role in disturbed fatty acid handling as observed in the metabolic syndrome and Type 2 diabetes mellitus (T2DM). Genetic variation in the CD36 gene may contribute to the aetiology of diabetes.

Methods: A population-based cohort in the Netherlands [age > 40 years and body mass index (BMI) > 25 kg/m2] of 675 subjects was phenotyped with respect to glucose metabolism with an oral glucose tolerance test and was genotyped for a known 478C-->T substitution and a C/T snp in the upstream promoter region (rs1527479) in the CD36 gene.

Validation of capillary glucose measurements to detect glucose intolerance or type 2 diabetes mellitus in the general population.

Background: The use of an oral glucose tolerance test (OGTT) has been recommended to diagnose type 2 diabetes, but an OGTT with venous blood sampling may not be feasible in the screening phase preceding large epidemiological studies. We have conducted a population-based screening in 2715 men and women and evaluated the diagnostic validity of capillary plasma glucose concentration measurements versus venous plasma glucose concentration measurements in a subset of 350 subjects.

Methods: During a single OGTT, glucose concentrations were measured in venous plasma as well as in capillary plasma.

Study on lifestyle-intervention and impaired glucose tolerance Maastricht (SLIM): design and screening results.

The study on lifestyle-intervention and impaired glucose tolerance Maastricht (SLIM) is a 3 years randomised clinical trial designed to evaluate the effect of a combined diet and physical activity intervention program on glucose tolerance in a Dutch population at increased risk for developing type 2 diabetes. Here the design of the lifestyle-intervention study is described and results are presented from the preliminary population screening, conducted between March 1999 and June 2000. In total, 2,820 subjects with an increased risk of having disturbances in glucose homeostasis (i.

Subscapular skinfold thickness distinguishes between transient and persistent impaired glucose tolerance: Study on Lifestyle-Intervention and Impaired Glucose Tolerance Maastricht (SLIM).

Aims: To assess whether adding anthropometric measurements to an oral glucose tolerance test (OGTT) can help to distinguish between transient and persistent impaired glucose tolerance (IGT).

Methods: From the SLIM project (Study on Lifestyle-Intervention and IGT Maastricht), a study designed to evaluate whether diet and physical activity intervention can improve glucose tolerance in subjects at risk for diabetes, 108 subjects with IGT underwent a repeated OGTT 2-4 months after the initial OGTT. Following the second test, subjects were classified as transient IGT, or persistent IGT.

Amino acid ingestion strongly enhances insulin secretion in patients with long-term type 2 diabetes.

Objective: Insulin secretion in response to carbohydrate intake is blunted in type 2 diabetic patients. However, it is not clear whether the insulin response to other stimuli, such as amino acids, is also diminished. Recently, we defined an optimal insulinoptropic mixture containing free leucine, phenylalanine, and a protein hydrolysate that substantially enhances the insulin response in healthy young subjects when coingested with carbohydrate.

Increased intima-media thickness in familial combined hyperlipidemia associated with apolipoprotein B.

The aim of the present study was to quantify intima-media thickness (IMT) in familial combined hyperlipidemia (FCHL) and to evaluate the relationship of IMT in FCHL-affected subjects with lipids and apolipoproteins, blood pressure values, and surrogate markers of insulin resistance. IMT was measured by ultrasound at the left and right common carotid arteries in 46 FCHL-affected subjects who were free of clinical manifestations of atherosclerosis and in 55 age- and sex-matched healthy control subjects. FCHL-affected subjects had significantly increased IMT compared with healthy control subjects, with a difference of 57 microm (age- and sex-corrected P<0.

Ingestion of protein hydrolysate and amino acid-carbohydrate mixtures increases postexercise plasma insulin responses in men.

To optimize the postexercise insulin response and to increase plasma amino acid availability, we studied postexercise insulin levels after the ingestion of carbohydrate and wheat protein hydrolysate with and without free leucine and phenylalanine. After an overnight fast, eight male cyclists visited our laboratory on five occasions, during which a control drink and two different beverage compositions in two different doses were tested. After they performed a glycogen-depletion protocol, subjects received a beverage (3.

Maximizing postexercise muscle glycogen synthesis: carbohydrate supplementation and the application of amino acid or protein hydrolysate mixtures.

Background: Postexercise muscle glycogen synthesis is an important factor in determining the time needed to recover from prolonged exercise.

Objective: This study investigated whether an increase in carbohydrate intake, ingestion of a mixture of protein hydrolysate and amino acids in combination with carbohydrate, or both results in higher postexercise muscle glycogen synthesis rates than does ingestion of 0.8 g*kg(-)(1)*h(-)(1) carbohydrate, provided at 30-min intervals.