Search PubMed⌕ Search

Biomedical subjects

Arne Astrup

Publications and source records attributed to Arne Astrup.

At least 37 records · Page 2Linked to original sources

The N363S polymorphism of the glucocorticoid receptor and metabolic syndrome factors in men.

OBJECTIVE: To test the associations between the N363S polymorphism of the glucocorticoid receptor gene (NR3C1) and factors related to the metabolic syndrome in middle-aged men with and without juvenile-onset obesity. RESEARCH METHODS AND PROCEDURES: This study included two groups of middle-aged men, who were originally identified at 20 years of age at the draft boards. One group (n = 208; age, 48 +/- 6 years) was selected on the basis of juvenile-onset obesity (BMI > or = 31 kg/m(2)). The other group consisted of mainly nonobese men randomly sampled from the same population in parallel with the obese men (n = 299; age, 50 +/- 7 years). The subjects were genotyped for the N363S polymorphism by polymerase chain reaction-restriction fragment length polymorphism. Body composition was measured by DXA. Glucose metabolism was evaluated by an oral glucose tolerance test, and the Matsudas index was calculated as a proxy for insulin sensitivity. Serum triglycerides and total and high-density lipoprotein-cholesterol were measured in the fasting state. RESULTS: Among the men with juvenile-onset obesity, carriers (n = 17) of the 363S allele had a lower whole body fat percentage, after accounting for differences in BMI and higher Matsudas index, compared with the noncarriers. The difference in Matsudas index lost statistical significance after the difference in body fat was accounted for. In the randomly sampled men, these variables did not relate to genotype. No relationship between carriers and noncarriers was found in body fat distribution or serum lipids. DISCUSSION: This study suggests that, in men developing obesity early in life, the 363S allele is associated with less adiposity at a given BMI, leading to higher insulin sensitivity.

Absorptiometry, Photon↗

Change in beta1-adrenergic receptor protein concentration in adipose tissue correlates with diet-induced weight loss.

The aim of the present study was to examine gene expression and protein concentrations of beta(1)- and beta(2)-adrenergic receptors in subcutaneous adipose tissue in obese subjects in response to weight loss. Eighteen obese subjects were studied during diet-induced weight loss. Beta-adrenergic receptor mRNA levels were quantified by reverse transcription-PCR-HPLC. Beta-adrenergic receptor protein concentrations were measured by Western blotting using fluorescence laser scanning for detection. Subjects lost 12.8+/-0.8 kg (mean+/-S.E.M.) during diet treatment. There was a 34% decrease in the beta(1)-adrenergic receptor mRNA level (0.92+/-0.09 compared with 0.61+/-0.06 amol/microg of DNA; P<0.002). Beta(2)-adrenergic receptor mRNA did not decrease significantly. Beta(2)-adrenergic receptor protein concentration decreased 37% (25.5+/-7.1 compared with 16.0+/-5.6 arbitrary units/ng of DNA; P=0.008), whereas beta(1)-adrenergic receptor protein concentration did not decrease significantly. The degree of weight loss was correlated with the concentration of beta(1)-adrenergic receptor protein (r=0.65, P<0.003) and changes in receptor protein concentration (r=0.50, P=0.035) during the very-low-calorie diet. In conclusion, the present study demonstrates a relationship between beta(1)-adrenergic receptor protein concentration in adipose tissue and the degree of weight loss. This relationship is not directly related to energy expenditure and deserves further investigation.

Adipose Tissue↗

The role of dietary fat in obesity.

Current scientific evidence indicates that dietary fat plays a role in weight loss and maintenance. Meta-analyses of intervention trials find that fat-reduced diets cause a 3-4-kg larger weight loss than normal-fat diets. A 10% reduction in dietary fat can cause a 4-5-kg weight loss in individuals with initial body mass index of 30 kg m (-2). Short-term trials show that nonfat dietary components are equally important. Sugar-sweetened beverages promote weight gain, and replacement of energy from fat by sugar-sweetened beverages is counterproductive in diets aimed at weight loss. Protein has been shown to be more satiating than carbohydrate, and fat-reduced diets with a high protein content (20-25% of energy) may increase weight loss significantly. There is little evidence that low-glycemic index foods facilitate weight control. Evidence linking certain fatty acids to body fatness is weak. Monounsaturated fatty acids may even be more fattening than polyunsaturated and saturated fats. No ad libitum dietary intervention study has shown that a normal-fat, high-monounsaturated fatty acid diet is comparable to a low-fat diet in preventing weight gain. Current evidence indicates that the best diet for prevention of weight gain, obesity, type 2 diabetes, and cardiovascular disease is low in fat and sugar-rich beverages and high in carbohydrates, fiber, grains, and protein.

Body Mass Index↗

Effect of sucrose on inflammatory markers in overweight humans.

BACKGROUND: Observational studies have found that dietary glycemic load is positively associated with C-reactive protein (CRP) concentrations in healthy humans, which suggests that the type of carbohydrate ingested influences inflammatory activity. OBJECTIVE: We investigated the effect of a diet with a high content of sucrose or artificial sweeteners on the inflammatory markers CRP, haptoglobin, and transferrin in overweight subjects. DESIGN: Overweight men and women consumed daily food and drink supplements containing either sucrose [n = 21; body mass index (BMI, in kg/m2): 28.0] or artificial sweeteners (n = 20; BMI: 27.6), predominantly from soft drinks (70%; average approximately 1.3 L/d) for 10 wk. RESULTS: During the intervention, sucrose intake increased by 151% in the sucrose group and decreased by 42% in the sweetener group, resulting in a 1.6-kg weight gain in the sucrose group and a 1.2-kg weight loss in the sweetener group over 10 wk (P < 0.001). Concentrations of haptoglobin, transferrin, and CRP increased by 13%, 5%, and 6%, respectively, in the sucrose group and decreased by 16%, 2%, and 26%, respectively, in the sweetener group (between-group differences: P = 0.006, P = 0.01, and P = 0.1, respectively). Adjustment for changes in body weight and energy intake did not substantially influence this outcome. CONCLUSIONS: The study shows that in the present group of overweight subjects a high consumption of sugar-sweetened foods and drinks increased haptoglobin and transferrin but had, at best, only a limited influence on CRP.

Adult↗

Comparison of two physical activity questionnaires in obese subjects: the NUGENOB study.

PURPOSE: Simple instruments are needed to assess habitual physical activity (PA) in obese subjects. In a multicenter European obesity project, we tested whether PA assessments by two questionnaires were correlated and similarly associated to selected obesity-related variables. METHODS: A total of 757 obese subjects (75% female; age 37.1 [7.9] yr, BMI 35.5 [4.9] kg.m(-2), mean [SD]) completed the Baecke questionnaire (assessing work, sport, and nonsport leisure activity) and the short last 7-d version of the International Physical Activity Questionnaire (IPAQ; assessing vigorous, moderate-intensity, walking activity, and sitting). We assessed percent body fat (bioimpedance), waist circumference, and fasting plasma concentrations of glucose, insulin, leptin, and FFA. Insulin sensitivity was assessed by the HOMA index for insulin resistance (HOMAIR). RESULTS: Using the IPAQ, only about one third of men and women were classified as insufficiently active. Total habitual PA assessments by the Baecke and IPAQ were significantly related (Spearman rho = 0.51 in total sample, P < or = 0.0001, with adjustment for age, gender, and center). Using principal component analysis, we built two uncorrelated indices corresponding to general obesity (determined by high body fat and leptin) and abdominal obesity (determined by high waist circumference and HOMAIR). PA scores from both questionnaires were negatively related to general and abdominal obesity indices, except for abdominal obesity with the IPAQ in men. CONCLUSIONS: Total PA assessments by the two questionnaires were found to correlate significantly, and the general pattern of associations of PA with general obesity was similar for the two questionnaires. However, the IPAQ may capture less of the relationships between PA and abdominal obesity than the Baecke, especially in men. Reporting of habitual PA in obese subjects with the IPAQ warrants further evaluation against objective assessment methods.

Adult↗

Mutation analysis of the MCHR1 gene in human obesity.

OBJECTIVE: The importance of the melanin-concentrating hormone (MCH) system for regulation of energy homeostasis and body weight has been demonstrated in rodents. We analysed the human MCH receptor 1 gene (MCHR1) with respect to human obesity. DESIGN: This consisted of genomic screening of 13.4 kb encompassing the MCHR1 in extremely obese German children and adolescents and association analyses for two coding single nucleotide polymorphisms (SNPs). To confirm initial positive association results, additional association studies and transmission disequilibrium tests in further German, Danish, French and American samples were conducted. Selected SNPs were investigated using functional in vitro studies and reporter gene assays. METHODS: Single-stranded conformation polymorphism analysis, re-sequencing, PCR-restriction fragment length polymorphism analyses, tetra-primer amplification refractory mutation systems, matrix-assisted laser desorption/ionization time of flight mass spectrometry and reporter gene assays were carried out as well as measuring inositol phosphate formation, inhibition of cAMP formation and activation of p42/44 MAP kinase. RESULTS: We identified 11 infrequent variations and two SNPs in the MCHR1 coding sequence and 18 SNPs (eight novel) in the flanking sequence. Association and transmission disequilibrium with obesity were detected for several SNPs in independent study groups of German obese children and adolescents and controls. In two German samples, encompassing 4056 and 295 individuals, trends towards association with obesity were detected. Findings in a second epidemiological German sample and in Danish, French and American samples were negative. Functional in vitro studies as well as reporter gene assays revealed no significant results. CONCLUSION: Our initial association of MCHR1 alleles/haplotype detected might be related to juvenile-onset obesity, conditional on a particular genetic and/or environmental background. Alternatively, we could not exclude the possibility that the initially detected association represented a false positive finding.

Adolescent↗

Food intake is inhibited by oral oleoylethanolamide.

Oleoylethanolamide (OEA) may be an endogenous regulator of food intake, and intraperitoneal injection of this compound decreases food intake in 24 h-starved rats. It is generally believed that this kind of lipid amide is rapidly catabolized in the gastrointestinal tract, thereby preventing its use as an oral antiobesity compound. We now show that oral OEA inhibits food intake dose dependently at 90 min after food presentation to starved rats. Food intake was reduced by 15.5% (P < 0.01) by administration of 10 mg/kg OEA. [(3)H]OEA was used to assess the degree of catabolism in the gastrointestinal tract. The endogenous level of this acylethanolamide was increased 11 times in the intestinal tissue (to 3.91 +/- 0.98 nmol/g tissue, mean +/- SEM) at 90 min after food presentation, based on the finding of 0.48% of the dose as intact OEA. These findings reveal unexpected properties of orally administered OEA, which may have potential as a cheap and safe antiobesity drug.

Administration, Oral↗

Major increase in prevalence of overweight and obesity between 1987 and 2001 among Danish adults.

OBJECTIVE: The aim of the study was to examine the secular trends in the prevalence of obesity (BMI >or= 30.0 kg/m(2)) and overweight (25.0 <or= BMI < 30.0 kg/m(2)) in Danish adults between 1987 and 2001. RESEARCH METHODS AND PROCEDURES: The study included self-reported weight and height of 10,094 men and 9897 women 16 to 98 years old, collected in a series of seven independent cross-sectional surveys. Prevalence and changes in prevalence of obesity and overweight stratified by sex and age groups were determined. RESULTS: The prevalence of obesity more than doubled between 1987 and 2001, in men from 5.6% to 11.8% [odds ratio (OR) = 2.3, 95% confidence interval (CI) = 1.9 to 2.8, p < 0.0001] and in women from 5.4% to 12.5% (OR = 2.6, 95% CI = 2.1 to 3.2, p < 0.0001), with the largest increase among the 16- to 29-year-old subjects (men, from 0.8% to 7.5%, OR = 10.2, 95% CI = 4.1 to 25.3, p < 0.0001; women, from 1.4% to 9.0% OR = 7.0, 95% CI = 3.5 to 14.1, p < 0.0001). Between 1987 and 2001, the prevalence of overweight increased from 34% to 40% in men and from 17% to 27% in women. DISCUSSION: The prevalence of overweight and obesity in Denmark has increased substantially between 1987 and 2001, particularly among young adults, a development that resembles that of other countries. There is clearly a need for early preventive efforts in childhood to limit the number of obesity-related complications in young adults.

Adolescent↗

Topiramate: long-term maintenance of weight loss induced by a low-calorie diet in obese subjects.

OBJECTIVE: To examine the safety and efficacy of topiramate (TPM) for maintaining weight following a low-calorie diet. RESEARCH METHODS AND PROCEDURES: Obese subjects (30 < or = BMI < 50 kg/m(2)) 18 to 75 years old received a low-calorie diet for 8 weeks. Those who lost > or =8% of their initial weight received TPM (96 or 192 mg/d) or placebo; all were on a lifestyle modification plan. Sixty weeks of medication were planned. Sponsor ended study early to develop a new controlled-release formulation with the potential to enhance tolerability and simplify dosing in this patient population. Efficacy was analyzed in subjects who completed 44 weeks of treatment before study termination. RESULTS: Of the 701 subjects enrolled, 80% lost > or =8% of their initial body weight and were randomized; 293 were analyzed for efficacy. Most withdrawals were due to premature termination of the study. Subjects receiving TPM lost 15.4% (96 mg/d) and 16.5% (192 mg/d) of their enrollment weight by week 44, compared with 8.9% in the placebo group (p < 0.001). Subjects on TPM continued to lose weight after the run-in, whereas those on placebo regained weight. Significantly more TPM subjects lost 5%, 10%, or 15% of their randomization weight than placebo. Most adverse events were related to the central nervous system. DISCUSSION: During a treatment period of 44 weeks, TPM was generally well tolerated, and subjects maintained weight loss initially achieved by a low-calorie diet-and produced additional clinically significant weight loss beyond that achieved by a low-calorie diet.

Adolescent↗

Combined dietary and pharmacological weight management in obese hypopituitary patients.

OBJECTIVE: The high prevalence of obesity and cardiovascular risk factors in hypopituitarism affirms the need for effective weight loss intervention. In this study, we investigated the combined effect of sibutramine, diet, and exercise in obese hypopituitary patients (HPs). RESEARCH METHODS AND PROCEDURES: In an open-label prospective intervention trial, 14 obese well-substituted nondiabetic HPs and 14 matched simple obese controls were allocated to 11-month treatment with sibutramine (10 to 15 mg), diet (600 kcal/d deficit), and exercise. Anthropometric indices and body composition (obtained from DXA scan) were assessed monthly for the first 5 months and thereafter every second month for the next 6 months. RESULTS: Mean (+/-SD) weight loss at 11 months was 11.3 +/- 4.8 kg in patients vs. 10.7 +/- 4.7 kg in controls. The HPs exhibited the same improvements in body composition, waist circumference, blood lipids, and fasting glucose as the simple obese. In a multivariate model, baseline weight, duration of growth hormone replacement therapy, and duration of pituitary disease explained 79% (p = 0.001) of the variation in weight loss at 4 months in the HPs. Only baseline weight and waist circumference could predict weight loss at 11 months. DISCUSSION: HPs are not resistant to weight loss therapy. Almost all will achieve at least 5% weight loss, and 60% can lose >10% weight within 11 months. However, the long-term effect on risk factors associated with type 2 diabetes and cardiovascular disease as well as on mortality needs to be established.

Adult↗

Topiramate: a new potential pharmacological treatment for obesity.

Obesity is a growing worldwide epidemic that is associated with serious medical complications. Although diet and exercise are often effective treatment in the short run, the weight lost is usually regained unless intensive intervention is maintained. Pharmacological adjunctive measures are clearly needed, and topiramate is currently being investigated as a possible new therapy for obesity. This paper reviews three clinical trials of topiramate for weight reduction in obese subjects: a 6-month dose-ranging study, a 2-year study of weight loss, and a 44-week study in subjects who had previously lost weight on a low-calorie diet. All three studies found topiramate to be significantly more efficacious than placebo. Notably, weight loss continued for 1 year and, perhaps, could have continued for a longer period. Topiramate was generally well tolerated, with adverse events being mild to moderate and mostly related to the central nervous system. Paresthesia was a frequent occurrence, but it did not lead to withdrawal of >5% of the subjects in any study.

Animals↗

The use of glycaemic index tables to predict glycaemic index of composite breakfast meals.

The applicability of the glycaemic index (GI) in the context of mixed meals and diets is still debatable. The objective of the present study was to investigate the predictability of measured GI in composite breakfast meals when calculated from table values, and to develop prediction equations using meal components. Furthermore, we aimed to study the relationship between GI and insulinaemic index (II). The study was a randomised cross-over meal test including twenty-eight healthy young men. Thirteen breakfast meals and a reference meal were tested. All meals contained 50 g available carbohydrate, but differed considerably in energy and macronutrient composition. Venous blood was sampled for 2 h and analysed for glucose and insulin. Prediction equations were made by regression analysis. No association was found between predicted and measured GI. The meal content of energy and fat was inversely associated with GI (R(2) 0.93 and 0.88, respectively; P<0.001). Carbohydrate content (expressed as percentage of energy) was positively related to GI (R(2) 0.80; P<0.001). Using multivariate analysis the GI of meals was best predicted by fat and protein contents (R(2) 0.93; P<0.001). There was no association between GI and II. In conclusion, the present results show that the GI of mixed meals calculated by table values does not predict the measured GI and furthermore that carbohydrates do not play the most important role for GI in mixed breakfast meals. Our prediction models show that the GI of mixed meals is more strongly correlated either with fat and protein content, or with energy content, than with carbohydrate content alone. Furthermore, GI was not correlated with II.

Adult↗

No difference in body weight decrease between a low-glycemic-index and a high-glycemic-index diet but reduced LDL cholesterol after 10-wk ad libitum intake of the low-glycemic-index diet.

BACKGROUND: The role of glycemic index (GI) in appetite and body-weight regulation is still not clear. OBJECTIVE: The objective of the study was to investigate the long-term effects of a low-fat, high-carbohydrate diet with either low glycemic index (LGI) or high glycemic index (HGI) on ad libitum energy intake, body weight, and composition, as well as on risk factors for type 2 diabetes and ischemic heart disease in overweight healthy subjects. DESIGN: The study was a 10-wk parallel, randomized, intervention trial with 2 matched groups. The LGI or HGI test foods, given as replacements for the subjects' usual carbohydrate-rich foods, were equal in total energy, energy density, dietary fiber, and macronutrient composition. Subjects were 45 (LGI diet: n = 23; HGI diet: n = 22) healthy overweight [body mass index (in kg/m(2)): 27.6 +/- 0.2] women aged 20-40 y. RESULTS: Energy intake, mean (+/- SEM) body weight (LGI diet: -1.9 +/- 0.5 kg; HGI diet: -1.3 +/- 0.3 kg), and fat mass (LGI diet: -1.0 +/- 0.4 kg; HGI diet: -0.4 +/- 0.3 kg) decreased over time, but the differences between groups were not significant. No significant differences were observed between groups in fasting serum insulin, homeostasis model assessment for relative insulin resistance, homeostasis model assessment for beta cell function, triacylglycerol, nonesterified fatty acids, or HDL cholesterol. However, a 10% decrease in LDL cholesterol (P < 0.05) and a tendency to a larger decrease in total cholesterol (P = 0.06) were observed with consumption of the LGI diet as compared with the HGI diet. CONCLUSIONS: This study does not support the contention that low-fat LGI diets are more beneficial than HGI diets with regard to appetite or body-weight regulation as evaluated over 10 wk. However, it confirms previous findings of a beneficial effect of LGI diets on risk factors for ischemic heart disease.

Adult↗