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1.
Neth Heart J ; 31(11): 415-423, 2023 Nov.
Article in English | MEDLINE | ID: mdl-36795219

ABSTRACT

Current guidelines barely support marine omega­3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in cardiology, mainly because results of large trials were equivocal. Most large trials have tested EPA alone or EPA + DHA combined as a drug, thereby disregarding the relevance of their blood levels. These levels are frequently assessed with the Omega­3 Index (percentage of EPA + DHA in erythrocytes), which is determined using a specific standardised analytical procedure. EPA and DHA are present in every human being at unpredictable levels (even in the absence of intake), and their bioavailability is complex. Both facts need to be incorporated into trial design and should direct clinical use of EPA and DHA. An Omega­3 Index in the target range of 8-11% is associated with lower total mortality, fewer major adverse cardiac and other cardiovascular events. Moreover, functions of organs such as the brain benefit from an Omega­3 Index in the target range, while untoward effects, such as bleeding or atrial fibrillation, are minimised. In pertinent intervention trials, several organ functions were improved, with improvements correlating with the Omega­3 Index. Thus, the Omega­3 Index is relevant in trial design and clinical medicine, which calls for a widely available standardised analytical procedure and a discussion on possible reimbursement of this test.

2.
Nutr Neurosci ; 23(2): 110-117, 2020 Feb.
Article in English | MEDLINE | ID: mdl-29806553

ABSTRACT

Objectives: The regulatory role of the brain in directing eating behavior becomes increasingly recognized. Although many areas in the brain have been found to respond to food cues, very little data is available after actual caloric intake. The aim of this study was to determine normal whole brain functional responses to ingestion of glucose after an overnight fast.Methods: Twenty-five normal weight, adult males underwent functional MRI on two separate visits. In a single-blind randomized study setup, participants received either glucose solution (50 g/300 ml of water) or plain water. We studied changes in Blood Oxygen Level Dependent (BOLD) signal, voxel-based connectivity by Eigenvector Centrality Mapping, and functional network connectivity.Results: Ingestion of glucose led to increased centrality in the thalamus and to decreases in BOLD signal in various brain areas. Decreases in connectivity in the sensory-motor and dorsal visual stream networks were found. Ingestion of water resulted in increased centrality across the brain, and increases in connectivity in the medial and lateral visual cortex network. Increased BOLD intensity was found in the intracalcarine and cingulate cortex.Discussion: Our data show that ingestion of glucose leads to decreased activity and connectivity in brain areas and networks linked to energy seeking and satiation. In contrast, drinking plain water leads to increased connectivity probably associated with continued food seeking and unfulfilled reward.Trail registration: This study combines data of two studies registered at clinicaltrails.gov under numbers NCT03202342 and NCT03247114.


Subject(s)
Brain/drug effects , Brain/physiology , Glucose/administration & dosage , Adolescent , Adult , Blood Glucose/analysis , Cross-Over Studies , Energy Intake , Energy Metabolism , Fasting , Glucose/metabolism , Humans , Insulin/blood , Magnetic Resonance Imaging , Male , Satiation/drug effects , Satiation/physiology , Single-Blind Method , Water/administration & dosage , Young Adult
3.
Obes Sci Pract ; 5(5): 459-467, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31687170

ABSTRACT

OBJECTIVES: The importance of the regulatory role of the brain in directing glucose homeostasis, energy homeostasis, eating behaviour, weight control and obesity is increasingly recognized. Brain activity in (sub)cortical neuronal networks involved in homeostatic control and hedonic responses is generally increased in persons with obesity. Currently, it is not known if these functional changes can be affected by dieting. The aim of the current study was to investigate whether prolonged fasting and/or weight loss influences neuronal brain activity in obese persons. METHODS: Fourteen participants with obesity were included (two male participants and 12 female participants, body mass index 35.2 ± 1.2 kg m-2). Whole-brain resting-state functional magnetic resonance imaging was performed after an overnight fast, after a prolonged 48-h fast and after an 8-week weight loss intervention. RESULTS: An 8-week weight loss intervention decreased BOLD signal in areas of the brain involved in salience, sensory motor and executive control. BOLD signal in these areas correlated with leptin levels and body mass index. CONCLUSIONS: Weight loss decreased activity in brain areas involved in feeding behaviour and reward processing. These results indicate that these obesity-associated alterations in neuronal activity are related to excessive body weight and might change after weight loss.

4.
Sci Rep ; 9(1): 11250, 2019 08 02.
Article in English | MEDLINE | ID: mdl-31375749

ABSTRACT

Although it is well known that food intake is affected by the palatability of food, the actual effect of flavoring on regulation of energy-homeostasis and reward perception by the brain, remains unclear. We investigated the effect of ethyl-butyrate (EB), a common non-caloric food flavoring, on the blood oxygen level dependent (BOLD) response in the hypothalamus (important in regulating energy homeostasis) and ventral tegmental area (VTA; important in reward processes). The 16 study participants (18-25 years, BMI 20-23 kg/m2) drank four study stimuli on separate visits using a crossover design during an fMRI setup in a randomized order. The stimuli were; plain water, water with EB, glucose solution (50gram/300 ml) and glucose solution with EB. BOLD responses to ingestion of the stimuli were determined in the hypothalamus and VTA as a measure of changes in neuronal activity after ingestion. In the hypothalamus and VTA, glucose had a significant effect on the BOLD response but EB flavoring did not. Glucose with and without EB led to similar decrease in hypothalamic BOLD response and glucose with EB resulted in a decrease in VTA BOLD response. Our results suggest that the changes in neuronal activity in the hypothalamus are mainly driven by energy ingestion and EB does not influence the hypothalamic response. Significant changes in VTA neuronal activity are elicited by energy combined with flavor.


Subject(s)
Hypothalamus/physiology , Reward , Taste/physiology , Ventral Tegmental Area/physiology , Administration, Oral , Adolescent , Adult , Animals , Butyrates/administration & dosage , Butyrates/metabolism , Cross-Over Studies , Eating/physiology , Energy Metabolism/physiology , Flavoring Agents/administration & dosage , Flavoring Agents/metabolism , Glucose/administration & dosage , Glucose/metabolism , Healthy Volunteers , Humans , Hypothalamus/cytology , Hypothalamus/diagnostic imaging , Magnetic Resonance Imaging , Male , Neurons/physiology , Ventral Tegmental Area/cytology , Ventral Tegmental Area/diagnostic imaging , Young Adult
5.
Nutrition ; 60: 80-86, 2019 04.
Article in English | MEDLINE | ID: mdl-30529886

ABSTRACT

OBJECTIVE: The brain is essential in regulating intake of food and beverages by balancing energy homeostasis, which is regulated by the hypothalamus, with reward perception, which is regulated by the ventral tegmental area (VTA). The aim of this study was to investigate the effects of ingestion of glucose, fructose, sucrose, and sucralose (a non-caloric artificial sweetener) on the magnitude and trajectory of the hypothalamic and the VTA blood oxygen level-dependent (BOLD) responses. METHOD: In five visits, 16 healthy men between 18 to 25 y of age with a body mass index between 20 and 23 kg/m2 drank five interventions in a randomized order while a functional magnetic resonance imaging scan was taken. The interventions consisted of 50 g of glucose, fructose, or sucrose, or 0.33 g of sucralose dissolved in 300 mL tap water. The control condition consisted of 300 mL of plain tap water. BOLD signals were determined in the hypothalamus and the VTA within a manually drawn region of interest. Differences in changes in BOLD signal between stimuli were analyzed using mixed models. RESULTS: Compared with the control condition, a decrease in BOLD signal in the hypothalamus was found after ingestion of glucose (P = 0.0003), and a lesser but delayed BOLD response was found after ingestion of sucrose (P = 0.006) and fructose (P = 0.003). Sucralose led to a smaller and transient response from the hypothalamus (P = 0.026). In the VTA, sucralose led to a very similar response to the water control condition, leading to an increase in VTA BOLD activity that continued over the measured time period. The natural sugars appeared to only lead to a transient increase in VTA activity. CONCLUSIONS: Glucose induces a deactivation in the hypothalamus immediately after ingestion and continued over the next 12 min, which is correlated with satiety signaling by the brain. Fructose and sucrose are both associated with a delayed and lesser response from the hypothalamus, likely because the sugars first have to be metabolized by the body. Sucralose leads to the smallest and most transient decrease in BOLD in the hypothalamus and leads to a similar response as plain water in the VTA, which indicates that sucralose might not have a similar satiating effect on the brain as the natural sugars.


Subject(s)
Brain/drug effects , Dietary Sugars/pharmacology , Energy Metabolism/drug effects , Homeostasis/drug effects , Sweetening Agents/pharmacology , Adolescent , Adult , Anhedonia/drug effects , Blood Gas Analysis , Body Mass Index , Brain/diagnostic imaging , Female , Fructose/pharmacology , Glucose/pharmacology , Healthy Volunteers , Humans , Hypothalamus/diagnostic imaging , Hypothalamus/drug effects , Magnetic Resonance Imaging , Male , Oxygen/analysis , Sucrose/analogs & derivatives , Sucrose/pharmacology , Ventral Tegmental Area/diagnostic imaging , Ventral Tegmental Area/drug effects , Young Adult
6.
Diabet Med ; 34(11): 1623-1628, 2017 11.
Article in English | MEDLINE | ID: mdl-28703888

ABSTRACT

AIMS: Individual indicators of socio-economic status have been associated with glycaemic control in people with Type 2 diabetes, but little is known about the association between partner's socio-economic status and HbA1c levels. We therefore examined the cross-sectional association between individual and partner's level of occupation on HbA1c levels in people with Type 2 diabetes in the Netherlands. METHODS: We included people with Type 2 diabetes with a partner who were treated in primary, secondary and tertiary care in the Diabetes Pearl cohort. Occupational level was classified according to International Standard Classification of Occupations (ISCO)-08 skill levels. Linear regression analyses were performed stratified for sex, and corrected for age, recruitment centre and diabetes medication. RESULTS: In total, 3257 participants (59.8% men, mean 62.2±9.4 years) were included. For men, having a partner with an intermediate level of occupation was associated with lower HbA1c levels [e.g. ISCO level 3: -2 mmol/mol (95% CI -4;-1) or -0.2% (95% CI -0.4;-0.1)], compared with having a partner of the highest occupational level (ISCO level 4). In women, having an unemployed partner was associated with higher HbA1c levels [14 mmol/mol (95% CI 6; 22) or 1.3% (95% CI 0.6; 2.0)], compared with having a partner of the highest occupational level. CONCLUSIONS: Partner's occupational status provided additional information on the association between socio-economic status and HbA1c levels in people with Type 2 diabetes. Women seemed to benefit from a partner with a higher occupational status, while men seemed to benefit from a partner with a lower status. Because of the cross-sectional nature of the present study, more research is necessary to explore this association.


Subject(s)
Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/epidemiology , Glycated Hemoglobin/analysis , Occupations , Spouses , Adult , Aged , Aged, 80 and over , Blood Glucose/analysis , Cohort Studies , Female , Humans , Male , Middle Aged , Netherlands/epidemiology , Occupations/statistics & numerical data , Social Class , Social Support , Spouses/statistics & numerical data , Young Adult
7.
Pharmacogenomics ; 16(11): 1267-76, 2015.
Article in English | MEDLINE | ID: mdl-26289095

ABSTRACT

AIM: SNPs may be associated with (side) effects of chemotherapy and may be useful as biomarkers to predict febrile neutropenia. PATIENTS & METHODS: 187 DNA samples extracted from formalin-fixed paraffin-embedded tissue from patients with stage II/III HER2-negative breast cancer were genotyped. RESULTS: Candidate SNPs were selected and explored for association with febrile neutropenia and/or pathological complete response. TT genotype of 388 C>T in FGFR4 (rs351855) had a tendency toward higher incidence of febrile neutropenia during neoadjuvant chemotherapy, compared with the CT (p = 0.383) genotype and compared with the CC genotype (p = 0.068). CONCLUSION: The TT genotype of 388 C>T FGFR4 may be related to incidence of febrile neutropenia during neoadjuvant TAC (docetaxel, doxorubicin, cyclophosphamide) chemotherapy and is possibly useful as a patient-related risk factor when assessing febrile neutropenia risk. Original submitted 23 January 2015; Revision submitted 26 May 2015.


Subject(s)
Anthracyclines/adverse effects , Anthracyclines/therapeutic use , Antibiotics, Antineoplastic/adverse effects , Antibiotics, Antineoplastic/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Febrile Neutropenia/chemically induced , Febrile Neutropenia/genetics , Germ-Line Mutation/genetics , Neoadjuvant Therapy/methods , Polymorphism, Genetic/genetics , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Febrile Neutropenia/epidemiology , Female , Genotype , Humans , Middle Aged , Polymorphism, Single Nucleotide/genetics , Risk Factors
8.
Sci Rep ; 5: 11525, 2015 Jun 19.
Article in English | MEDLINE | ID: mdl-26089239

ABSTRACT

Few studies have included subjects with the propensity to reach old age in good health, with the aim to disentangle mechanisms contributing to staying healthier for longer. The hypothalamic-pituitary-thyroid (HPT) axis maintains circulating levels of thyroid stimulating hormone (TSH) and thyroid hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring of nonagenarians with at least one nonagenarian sibling have increased TSH secretion but similar bioactivity of TSH and similar TH levels compared to controls. Healthy offspring and spousal controls had similar resting metabolic rate and core body temperature. We propose that pleiotropic effects of the HPT axis may favour longevity without altering energy metabolism.


Subject(s)
Energy Metabolism , Longevity , Thyrotropin/metabolism , Aged, 80 and over , Comorbidity , Family , Female , Humans , Hypothalamo-Hypophyseal System/metabolism , Iodine/metabolism , Male , Risk Factors , Thyroid Hormones/blood , Thyroid Hormones/metabolism , Thyrotropin/blood
9.
Behav Brain Res ; 287: 127-34, 2015.
Article in English | MEDLINE | ID: mdl-25779924

ABSTRACT

We hypothesized that brain circuits involved in reward and salience respond differently to fasting in obese versus lean individuals. We compared functional connectivity networks related to food reward and saliency after an overnight fast (baseline) and after a prolonged fast of 48 h in lean versus obese subjects. We included 13 obese (2 males, 11 females, BMI 35.4 ± 1.2 kg/m(2), age 31 ± 3 years) and 11 lean subjects (2 males, 9 females, BMI 23.2 ± 0.5 kg/m(2), age 28 ± 3 years). Resting-state functional magnetic resonance imaging scans were made after an overnight fast (baseline) and after a prolonged 48 h fast. Functional connectivity of the amygdala, hypothalamus and posterior cingulate cortex (default-mode) networks was assessed using seed-based correlations. At baseline, we found a stronger connectivity between hypothalamus and left insula in the obese subjects. This effect diminished upon the prolonged fast. After prolonged fasting, connectivity of the hypothalamus with the dorsal anterior cingulate cortex (dACC) increased in lean subjects and decreased in obese subjects. Amygdala connectivity with the ventromedial prefrontal cortex was stronger in lean subjects at baseline, which did not change upon the prolonged fast. No differences in posterior cingulate cortex connectivity were observed. In conclusion, obesity is marked by alterations in functional connectivity networks involved in food reward and salience. Prolonged fasting differentially affected hypothalamic connections with the dACC and the insula between obese and lean subjects. Our data support the idea that food reward and nutrient deprivation are differently perceived and/or processed in obesity.


Subject(s)
Brain/physiopathology , Fasting/physiology , Obesity/physiopathology , Adult , Brain Mapping , Female , Food , Humans , Magnetic Resonance Imaging , Male , Neural Pathways/physiopathology , Rest , Reward
10.
Nutr Metab Cardiovasc Dis ; 25(4): 403-10, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25698153

ABSTRACT

BACKGROUND AND AIMS: South Asians have a higher risk of developing cardiovascular disease than white Caucasians. The underlying cause is unknown, but might be related to higher cardiac susceptibility to metabolic disorders. Short-term caloric restriction (CR) can be used as a metabolic stress test to study cardiac flexibility. We assessed whether metabolic and functional cardiovascular flexibility to CR differs between South Asians and white Caucasians. METHODS AND RESULTS: Cardiovascular function and myocardial triglycerides were assessed using a 1.5T-MRI/S-scanner in 12 middle-aged overweight male South Asians and 12 matched white Caucasians before and after an 8-day very low calorie diet (VLCD). At baseline South Asians were more insulin resistant than Caucasians. Cardiac dimensions were smaller, despite correction for body surface area, and pulse wave velocity (PWV) in the distal aorta was higher in South Asians. Systolic and diastolic function, myocardial triglycerides and pericardial fat did not differ significantly between groups. After the VLCD body weight reduced on average by 4.0 ± 0.2 kg. Myocardial triglycerides increased in both ethnicities by 69 ± 18%, and diastolic function decreased although this was not significant in South Asians. However, pericardial fat and PWV in the proximal and total aorta were reduced in Caucasians only. CONCLUSION: Myocardial triglyceride stores in middle-aged overweight and insulin resistant South Asians are as flexible and amenable to therapeutic intervention by CR as age-, sex- and BMI-matched but less insulin resistant white Caucasians. However, paracardial fat volume and PWV showed a differential effect in response to an 8-day VLCD in favor of Caucasians. CLINICAL TRIAL REGISTRATION: NTR 2473 (URL: http://www.trialregister.nl/trialreg/admin/rctsearch.asp?Term=2473).


Subject(s)
Asian People , Caloric Restriction , Cardiovascular System/metabolism , Overweight/blood , White People , Adipose Tissue/metabolism , Adult , Blood Glucose/metabolism , Body Mass Index , Body Surface Area , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Glycated Hemoglobin/metabolism , Humans , Insulin/blood , Insulin Resistance , Male , Middle Aged , Myocardium/metabolism , Prospective Studies , Pulse Wave Analysis , Triglycerides/blood
11.
Breast Cancer Res Treat ; 149(2): 461-6, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25556355

ABSTRACT

This side study investigated the effect of chemotherapy on thyroid function and the extent to which it can predict pathological complete response (pCR) in patients with early breast cancer taking part in NEOZOTAC phase III trial, randomizing between neoadjuvant chemotherapy with or without additional zoledronic acid. Moreover, we examined the impact of thyroid function on toxicity. Serum samples of 38 patients were available for analyses. Free thyroxin (fT4) and thyroid stimulating hormone (TSH) levels were compared between baseline and before the 6th cycle and between subjects with and without pCR. The relation between toxicity and the variation in fT4 and TSH levels during chemotherapy was tested. Samples at baseline and before the 6th cycle were available for 31 and 21 patients, respectively. The mean baseline fT4 level was 16.0 pmol/L and TSH level 1.11 mU/L, and these did not differ between both arms at each time point. During six cycles of chemotherapy, fT4 levels decreased (p = 0.0001), and TSH levels increased significantly (p = 0.019). Interestingly, the decrease of fT4 was significantly greater in patients without nausea, vomiting, or neuropathy, than in patients with those side effects (p = 0.037, p = 0.043, and p = 0.050, respectively). Baseline TSH levels tended to be higher in patients with pCR (p = 0.035 univariate analysis and p = 0.074 multivariate analysis). Chemotherapy blunts thyroid function, which was associated with less side effects. These data urge further evaluation of the effects of thyroid function on toxicity and outcome of breast cancer therapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/blood , Breast Neoplasms/drug therapy , Thyrotropin/blood , Thyroxine/blood , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Biomarkers, Tumor/metabolism , Breast Neoplasms/pathology , Female , Humans , Middle Aged , Neoadjuvant Therapy , Neoplasm Staging , Thyroid Function Tests , Thyroid Gland/drug effects , Thyroid Gland/metabolism , Treatment Outcome
12.
Diabet Med ; 31(8): 1001-8, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24724616

ABSTRACT

AIMS: Modulation of dopamine receptor D2 (DRD2) activity affects insulin secretion in both rodents and isolated pancreatic ß-cells. We hypothesized that single nucleotide polymorphisms in the DRD2/ANKK1 locus may affect susceptibility to type 2 diabetes in humans. METHODS: Four potentially functional variants in the coding region of the DRD2/ANKK1 locus (rs1079597, rs6275, rs6277, rs1800497) were genotyped and analysed for type 2 diabetes susceptibility in up to 25 000 people (8148 with type 2 diabetes and 17687 control subjects) from two large independent Dutch cohorts and one Danish cohort. In addition, 340 Dutch subjects underwent a 2-h hyperglycaemic clamp to investigate insulin secretion. Since sexual dimorphic associations related to DRD2 polymorphisms have been previously reported, we also performed a gender-stratified analysis. RESULTS: rs1800497 at the DRD2/ANKK1 locus was associated with a significantly increased risk for type 2 diabetes in women (odds ratio 1.14 (1.06-1.23); P = 4.1*104) but not in men (odds ratio 1.00 (95% CI 0.93-1.07); P = 0.92) or the combined group. Although rs1800497 was not associated with insulin secretion, we did find another single nucleotide polymorphism in this locus, rs6275, to be associated with increased first-phase glucose-stimulated insulin secretion in women (P = 5.5*104) but again not in men (P = 0.34). CONCLUSION: The present data identify DRD2/ANKK1 as a potential sex-specific type 2 diabetes susceptibility gene.


Subject(s)
Diabetes Mellitus, Type 2/genetics , Genetic Predisposition to Disease , Insulin Resistance , Insulin-Secreting Cells/metabolism , Insulin/metabolism , Polymorphism, Single Nucleotide , Receptors, Dopamine D2/genetics , Alleles , Case-Control Studies , Cohort Studies , Denmark , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/metabolism , Female , Gene Frequency , Genetic Association Studies , Genetic Loci , Humans , Hyperglycemia/blood , Hyperglycemia/genetics , Hyperglycemia/metabolism , Insulin/blood , Insulin Secretion , Male , Middle Aged , Netherlands , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Receptors, Dopamine D2/metabolism , Sex Characteristics
13.
Int J Obes (Lond) ; 38(5): 746-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24100424

ABSTRACT

Telomere length can be considered as a biological marker for cell proliferation and aging. Obesity is associated with adipocyte hypertrophy and proliferation as well as with shorter telomeres in adipose tissue. As adipose tissue is a mixture of different cell types and the cellular composition of adipose tissue changes with obesity, it is unclear what determines telomere length of whole adipose tissue. We aimed to investigate telomere length in whole adipose tissue and isolated adipocytes in relation to adiposity, adipocyte hypertrophy and adipose tissue inflammation and fibrosis. Telomere length was measured by real-time PCR in visceral adipose tissue, and isolated adipocytes of 21 obese women with a waist ranging from 110 to 147 cm and age from 31 to 61 years. Telomere length in adipocytes was shorter than in whole adipose tissue. Telomere length of adipocytes but not whole adipose tissue correlated negatively with waist and adipocyte size, which was still significant after correction for age. Telomere length of whole adipose tissue associated negatively with fibrosis as determined by collagen content. Thus, in extremely obese individuals, adipocyte telomere length is a marker of adiposity, whereas whole adipose tissue telomere length reflects the extent of fibrosis and may indicate adipose tissue dysfunction.


Subject(s)
Fibrosis/pathology , Intra-Abdominal Fat/pathology , Obesity, Morbid/pathology , Adipocytes/ultrastructure , Adult , Female , Fibrosis/genetics , Humans , Hypertrophy , Middle Aged , Obesity, Morbid/genetics , Real-Time Polymerase Chain Reaction , Telomere/ultrastructure
14.
Br J Pharmacol ; 170(4): 908-18, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23957854

ABSTRACT

BACKGROUND AND PURPOSE: Topiramate improves insulin sensitivity, in addition to its antiepileptic action. However, the underlying mechanism is unknown. Therefore, the present study was aimed at investigating the mechanism of the insulin-sensitizing effect of topiramate both in vivo and in vitro. EXPERIMENTAL APPROACH: Male C57Bl/6J mice were fed a run-in high-fat diet for 6 weeks, before receiving topiramate or vehicle mixed in high-fat diet for an additional 6 weeks. Insulin sensitivity was assessed by hyperinsulinaemic-euglycaemic clamp. The extent to which the insulin sensitizing effects of topiramate were mediated through the CNS were determined by concomitant i.c.v. infusion of vehicle or tolbutamide, an inhibitor of ATP-sensitive potassium channels in neurons. The direct effects of topiramate on insulin signalling and glucose uptake were assessed in vivo and in cultured muscle cells. KEY RESULTS: In hyperinsulinaemic-euglycaemic clamp conditions, therapeutic plasma concentrations of topiramate (∼4 µg·mL(-1) ) improved insulin sensitivity (glucose infusion rate + 58%). Using 2-deoxy-D-[(3) H]glucose, we established that topiramate improved the insulin-mediated glucose uptake by heart (+92%), muscle (+116%) and adipose tissue (+586%). Upon i.c.v. tolbutamide, the insulin-sensitizing effect of topiramate was completely abrogated. Topiramate did not directly affect glucose uptake or insulin signalling neither in vivo nor in cultured muscle cells. CONCLUSION AND IMPLICATIONS: In conclusion, topiramate stimulates insulin-mediated glucose uptake in vivo through the CNS. These observations illustrate the possibility of pharmacological modulation of peripheral insulin resistance through a target in the CNS.


Subject(s)
Anticonvulsants/pharmacology , Central Nervous System/drug effects , Fructose/analogs & derivatives , Insulin Resistance , KATP Channels/antagonists & inhibitors , Muscle Fibers, Skeletal/drug effects , Potassium Channel Blockers/pharmacology , Animals , Anticonvulsants/administration & dosage , Blood Glucose/drug effects , Blood Glucose/metabolism , Cell Line , Central Nervous System/metabolism , Diet, High-Fat , Disease Models, Animal , Fructose/administration & dosage , Fructose/pharmacology , Infusions, Intraventricular , Insulin/blood , KATP Channels/metabolism , Male , Mice , Mice, Inbred C57BL , Muscle Fibers, Skeletal/metabolism , Potassium Channel Blockers/administration & dosage , Signal Transduction/drug effects , Topiramate
15.
Clin Endocrinol (Oxf) ; 79(5): 648-51, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23252937

ABSTRACT

OBJECTIVE: Heart rate variability (HRV) reflects the balance of activities of sympathetic and parasympathetic components of the autonomic nervous system. We compared HRV parameters in response to a prolonged fast in obese versus normal weight humans. In addition, the effect of weight-loss was evaluated in obese individuals. DESIGN: Intervention study. PATIENTS: The study subjects included 14 nondiabetic obese (12 females/2 males, aged 30 ± 3 years, Body Mass Index (BMI) 35·2 ± 1·2 kg/m(2) ) and 12 lean subjects (10 females/2 males, aged 27 ± 3 years, BMI 23·3 ± 0·5 kg/m(2) ). MEASUREMENTS: HRV was examined 75 min after standardized breakfast and after a 48-h fast in 14 nondiabetic obese and 12 lean subjects. The postprandial measurement was repeated in 12 obese subjects after weight-loss. RESULTS: In lean subjects, fasting decreased high-frequency (HF) power by 43% (P < 0·05) and decreased low-frequency (LF) power by 37% (P = 0·1), leaving the LF/HF ratio unchanged (P = 0·7). In the obese group, autonomic nervous system tone shifted to sympathetic dominance as the LF/HF increased from 0·61 to 1·14 (P = 0·03). After an average weight-loss of 13·8 kg in obese subjects, a trend for sympathetic dominance was found; the LF/HF ratio increased by 56% (P = 0·06). CONCLUSION: Our data show that a 48-h fast leaves autonomic nervous system balance unaltered in lean subjects. In contrast, a 48-h fast, as well as weight-loss, induces sympathetic dominance in obese humans.


Subject(s)
Autonomic Nervous System/physiology , Heart Rate/physiology , Obesity/physiopathology , Adult , Autonomic Nervous System/metabolism , Body Mass Index , Female , Humans , Male , Thinness/physiopathology , Weight Loss/physiology
16.
Int J Endocrinol ; 2012: 983814, 2012.
Article in English | MEDLINE | ID: mdl-22675355

ABSTRACT

The storage of triglyceride (TG) droplets in nonadipose tissues is called ectopic fat storage. Ectopic fat is associated with insulin resistance and type 2 diabetes mellitus (T2DM). Not the triglycerides per se but the accumulation of intermediates of lipid metabolism in organs, such as the liver, skeletal muscle, and heart seem to disrupt metabolic processes and impair organ function. We describe the mechanisms of ectopic fat depositions in the liver, skeletal muscle, and in and around the heart and the consequences for each organs function. In addition, we systematically reviewed the literature for the effects of diet-induced weight loss and exercise on ectopic fat depositions.

17.
Exp Diabetes Res ; 2011: 928523, 2011.
Article in English | MEDLINE | ID: mdl-21603181

ABSTRACT

High fat feeding induces a variety of obese and lean phenotypes in inbred rodents. Compared to Diet Resistant (DR) rodents, Diet Induced Obese (DIO) rodents are insulin resistant and have a reduced dopamine receptor D2 (DRD2) mediated tone. We hypothesized that this differing dopaminergic tone contributes to the distinct metabolic profiles of these animals. C57Bl6 mice were classified as DIO or DR based on their weight gain during 10 weeks of high fat feeding. Subsequently DIO mice were treated with the DRD2 agonist bromocriptine and DR mice with the DRD2 antagonist haloperidol for 2 weeks. Compared to DR mice, the bodyweight of DIO mice was higher and their insulin sensitivity decreased. Haloperidol treatment reduced the voluntary activity and energy expenditure of DR mice and induced insulin resistance in these mice. Conversely, bromocriptine treatment tended to reduce bodyweight and voluntary activity, and reinforce insulin action in DIO mice. These results show that DRD2 activation partly redirects high fat diet induced metabolic anomalies in obesity-prone mice. Conversely, blocking DRD2 induces an adverse metabolic profile in mice that are inherently resistant to the deleterious effects of high fat food. This suggests that dopaminergic neurotransmission is involved in the control of metabolic phenotype.


Subject(s)
Dopamine Agonists/therapeutic use , Dopamine Antagonists/toxicity , Energy Metabolism/drug effects , Obesity/drug therapy , Receptors, Dopamine D2/physiology , Synaptic Transmission/drug effects , Animals , Behavior, Animal/drug effects , Body Weight/drug effects , Bromocriptine/therapeutic use , Dietary Fats/adverse effects , Dopamine D2 Receptor Antagonists , Haloperidol/toxicity , Insulin Resistance , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Motor Activity/drug effects , Obesity/chemically induced , Obesity/metabolism , Phenotype , Random Allocation , Receptors, Dopamine D2/agonists
18.
Neth J Med ; 69(4): 159-66, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21527802

ABSTRACT

This paper delineates the evolutionary background of the unprecedented epidemic of obesity that has evolved over the last century. Some two million years ago, a change of climate in the habitat of our primate ancestors triggered dietary adaptations which allowed our brain to grow. A shift from principally carbohydrate-based to fish- and meat-based eating habits provided sufficient fuel and building blocks to facilitate encephalisation. Insulin resistance may have evolved simultaneously as a means to avert the danger of hypoglycaemia to the brain (in view of the reduction of carbohydrate intake). Ensuing cognitive capacities enabled the control of fire and the manufacturing of tools, which increased energy yield from food even further and eased the defence against predators. The latter development relieved the selective pressure to maintain an upper level of bodyweight (driven by predation of overweight ndividuals). Since then, random mutations allowing bodyweight to increase spread in the human gene pool by genetic drift. Also, (seasonal) food insecurity in hunter-gatherer societies spurred the evolution of thrifty genes to maximise nutrient intake and energy storage when food was available. The agricultural and industrial revolutions rapidly changed our habitat: virtually unlimited stocks of (refined) foodstuffs and mechanical substitutes of physical efforts push up energy balance, particularly in those of us who are still adapted to former environmental conditions: i.e. who carry thrifty genes and lack (genetic) protection against weight gain. Intrauterine epigenetic mechanisms potentially reinforce the impact of these genes on the propensity to grow obese.


Subject(s)
Biological Evolution , Diabetes Mellitus, Type 2/genetics , Energy Intake/physiology , Obesity/epidemiology , Obesity/genetics , Brain/growth & development , Cognition , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/pathology , Diet , Dietary Carbohydrates/administration & dosage , Dietary Fats/administration & dosage , Food Supply , Genetic Predisposition to Disease , Global Health , Humans , Insulin Resistance , Nutritional Status , Obesity/pathology , Risk Factors
19.
J Neuroendocrinol ; 23(6): 519-24, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21466597

ABSTRACT

Recently, a massive loss of both hypocretin and melanin-concentrating hormone (MCH) neurones was found in the hypothalamus of Parkinson's disease (PD) patients. Because both hypocretin and MCH play a key role in the regulation of sleep, energy homeostasis and autonomic function, partly by modulation of the somatotrophic, thyrotrophic and lactotrophic axes, neuroendocrine dysregulation may contribute to some of the non-motor features of PD. In eight de novo, medication-free PD patients and eight age-, sex- and body mass index-matched controls, we measured serum levels of growth hormone (GH), thyroid-stimulating hormone (TSH) and prolactin every 10 min for 24 h. Auto-deconvolution, cosinor and approximate entropy analysis were applied to quantify GH, TSH and prolactin secretion rates, diurnal rhythmicity, as well as regularity of hormone release. Sleep was polygraphically-recorded throughout the night. Total 24-h secretion of GH (191 ± 31 versus 130 ± 39 mU/l/24 h), TSH (38 ± 9 versus 36 ± 2 mU/l/24 h) and prolactin (102 ± 14 versus 116 ± 17 µg/l/24 h), as well as their diurnal rhythmicity and regularity of release, were not significantly different between PD patients and controls (all P ≥ 0.12). Fasting levels of insulin-like growth factor-1 were also unaltered in PD patients. However, free thyroxine (T(4) ) levels were significantly higher in PD patients compared to controls (16.19 ± 0.80 versus 13.88 ± 0.40 pmol/l; P = 0.031). In PD patients, prolactin levels were related to disease duration (r = 0.76, P = 0.028), whereas both GH (r = -0.91, P = 0.002) and free T(4) (r = -0.71, P = 0.050) levels correlated inversely with body fat content. Apart from a mild increase in free T(4) levels, we found no indications for altered somatotrophic, thyrotrophic and lactotrophic axes activity in early-stage PD patients.


Subject(s)
Human Growth Hormone/metabolism , Parkinson Disease/metabolism , Prolactin/metabolism , Thyrotropin/metabolism , Case-Control Studies , Circadian Rhythm/physiology , Female , Human Growth Hormone/blood , Humans , Insulin-Like Growth Factor Binding Protein 3 , Insulin-Like Growth Factor Binding Proteins/analysis , Insulin-Like Growth Factor Binding Proteins/blood , Insulin-Like Growth Factor I/analysis , Male , Metabolome/physiology , Middle Aged , Parkinson Disease/blood , Parkinson Disease/physiopathology , Prolactin/blood , Sleep/physiology , Thyroid Hormones/blood , Thyrotropin/blood
20.
Nutr Diabetes ; 1: e9, 2011 Oct 03.
Article in English | MEDLINE | ID: mdl-23455021

ABSTRACT

BACKGROUND: Behavioral lifestyle intervention, combined with parental involvement, is preferred over standard care or self-help in childhood obesity. The short-term results of such interventions are promising, but long-term follow-up results are equivocal. OBJECTIVE: The objective of the present study was the short (3 months) and long-term (1 and 2 years follow-up) effect evaluation of a family-based multidisciplinary cognitive behavioral lifestyle intervention on markers of adiposity, metabolism, inflammation and physical fitness compared with standard care in children with obesity. Also the association between these outcome variables was determined. METHODS: In this prospective longitudinal clinical trial, obese children were randomly assigned to a 3-month family-based cognitive behavioral multidisciplinary lifestyle treatment (n=40; body mass index-standard deviation score (BMI-SDS) 4.2±0.7; age; 13.3±2.0 years) or to a control group receiving an initial advice on physical activity and nutrition (n=39; BMI-SDS 4.3±0.6; age 13.1±1.9 years). Anthropometric data, physical fitness, metabolic parameters and inflammatory state were evaluated at baseline, after intervention (at 3 months) and at 1-year follow-up. At 2-year follow-up, anthropometric data and physical fitness were measured in the intervention group. RESULTS: An intervention effect after 1 year was found for adiposity (P=0.02 for BMI-SDS, P=0.03 for waist circumference (WC)-SDS), physical fitness (absolute measured peak value of oxygen uptake (ml min(-1)), standardized for age and gender (VO2peak-SDS), P<0.01) and insulin resistance (HOMA-SDS, P=0.04). No significant intervention effect was found for serum lipid profile, high-sensitive C-reactive protein or for adiponectin. At 2-year follow-up, BMI-SDS in the intervention group (n=31) was 3.8±1.2 SDS, significantly less than at baseline (P=0.02). CONCLUSION: A positive 1-year follow-up treatment effect was found for adiposity, physical fitness and glucose homeostasis, but not for inflammatory markers. There was a significant long-term treatment effect on adiposity, although almost all children remained obese.

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