bluuebunny/crossref_metadata_2025_split huggingface dataset:
Leptin Production by the Stomach Is Up‐Regulated in Obese (fa/fa) Zucker Rats
Authors: Picó Catalina , Sánchez Juana , Oliver Paula , Palou Andreu 
Published: April 2008

AbstractObjective: Genetically obese (fa/fa) Zucker rats display markedly elevated circulating leptin levels compared with their lean counterparts; this is expected because of the lack of a LepR‐mediated feedback inhibition. The aim of this study was to determine the effect of the leptin receptor mutation in the Zucker rat on gastric leptin production and on the response to 14 hours of starvation. The response to a short‐term period of food intake (20 minutes) on gastric leptin release was also analyzed.Research Methods and Procedures: Leptin mRNA expression in the gastric mucosa and in adipose tissue depots (epididymal, retroperitoneal, mesenteric, and inguinal) was assessed by reverse transcriptase‐polymerase chain reaction and serum and stomach leptin content by enzyme‐linked immunosorbent assay.Results: Obese Zucker rats overexpressed leptin in the stomach. They overexpress leptin in the inguinal adipose tissue but not in visceral adipose tissue depots, indicating tissue‐specific obesity‐dependent differences. Gastric leptin expression is regulated by feeding conditions in lean but not in obese (fa/fa) rats. In lean animals, leptin mRNA levels decrease in fasting conditions and increase rapidly with a short period of food intake. Obese Zucker rats also overdisplay stomach leptin levels. Feeding acutely stimulates leptin secretion by the stomach in lean, and to a lesser extent, in obese rats.Discussion: These results indicate impaired regulation of leptin expression in the stomach of obese (fa/fa) Zucker rats. However, there is still an effect of the nutritional status on gastric leptin levels despite the lack of a functional leptin receptor.
Effects of Dietary Fatty Acids and Exercise on Body‐Weight Regulation and Metabolism in Rats
Authors: Pellizzon Michael , Buison Anne , Ordiz Frank , Ana Lardo Santa , Jen K.‐L. Catherine 
Published: April 2008

AbstractObjective: To assess the interaction of high‐fat diets (HF) made with different dietary fatty acids and exercise on body‐weight regulation, adiposity, and metabolism.Research Methods and Procedures: Male Wistar rats born to dams fed HF diets (40% w/w) made with either fish oil (FO), soybean oil (SO), or palm oil (PO) were fed diets similar to their dams and divided randomly into exercise (EX, swimming) or sedentary control (SD) groups when they were 9 weeks old. EX lasted for 6 weeks. Twenty‐four hours after the last EX bout, fasted rats were killed by decapitation. Chemical analyses and body composition analysis were conducted.Results: The results demonstrated that different fatty acids had different effects on body weight, composition, and metabolism. SO‐fed rats gained the most weight and fat. EX reduced body weight of FO‐ and PO‐fed rats, but SO‐fed rats were still heavier and fatter than other rats. Data from SO‐ and PO‐fed rats suggested that they are insulin resistant and that EX normalized this abnormality. Of the three HF diets used, FO produced the least adverse effects compared with PO and SO.Discussion: Not only the quantity of dietary fat, but also the type of fat used, will produce different effects on body weight and metabolism. EX ameliorates the suggested insulin resistance induced in rats fed either highly saturated or n‐6 polyunsaturated fatty acids. Long‐chain n‐3 polyunsaturated fatty acids, as found in fish oil, are more beneficial than n‐6 polyunsaturated fatty acids when fed in high amounts to rats.
Long‐Term Weight Loss and Breakfast in Subjects in the National Weight Control Registry
Authors: Wyatt Holly R. , Grunwald Gary K. , Mosca Cecilia L. , Klem Mary L. , Wing Rena R. , Hill James O. 
Published: April 2008

AbstractObjective: To examine breakfast consumption in subjects maintaining a weight loss in the National Weight Control Registry (NWCR).Research Methods and Procedures: A cross‐sectional study in which 2959 subjects in the NWCR completed demographic and weight history questionnaires as well as questions about their current breakfast consumption. All subjects had maintained a weight loss of at least 13.6 kg (30 lb) for at least 1 year; on average these subjects had lost 32 kg and kept it off for 6 years.Results: A large proportion of NWCR subjects (2313 or 78%) reported regularly eating breakfast every day of the week. Only 114 subjects (4%) reported never eating breakfast. There was no difference in reported energy intake between breakfast eaters and non‐eaters, but breakfast eaters reported slightly more physical activity than non‐breakfast eaters (p = 0.05).Discussion: Eating breakfast is a characteristic common to successful weight loss maintainers and may be a factor in their success.
Obesity, Aerobic Exercise, and Vascular Disease: The Role of Oxidant Stress
Authors: Fenster Catherine P. , Weinsier Roland L. , Darley‐Usmar Victor M. , Patel Rakesh P. 
Published: April 2008

AbstractOxidant formation in the vasculature contributes to vascular disease and dysfunction associated with obesity. In contrast, exercise‐dependent production of oxidants may stimulate adaptive responses that protect against the development of such diseases. In this review, we discuss current concepts in the biology of reactive oxygen and nitrogen species and how their function is modulated in the context of vascular disease, obesity, and aerobic exercise.
DXA: Potential for Creating a Metabolic Map of Organ‐Tissue Resting Energy Expenditure Components
Authors: Hayes Matthew , Chustek Michael , Wang ZiMian , Gallagher Dympna , Heshka Stanley , Spungen Ann , Bauman William , Heymsfield Steven B. 
Published: April 2008

AbstractObjective: This study tested the hypothesis that tissue‐organ components can be derived from DXA measurements, and in turn, resting energy expenditure (REE) can be calculated from the summed heat productions of DXA‐estimated brain, skeletal muscle mass (SM), adipose tissue, bone, and residual mass (RM).Research Methods and Procedures: Subjects were divided into five groups of adults <50 years of age. The specific metabolic rate of RM was developed in 13 Group I healthy subjects and a DXA‐brain mass prediction formula in 52 Group II subjects. SM, adipose tissue, and bone models were developed based on earlier reports. The composite REE prediction model (REEp) was tested in 154 Group III subjects in whom REEp was compared with measured REE (REEm). Features of the developed model were determined in 94 normal‐weight men and women (Group IV) and seven spinal cord injury patients and healthy matched controls (Group V).Results: REEp and REEm in Group III were highly correlated (y = 0.85x + 233; r = 0.82, p < 0.001), and no bias was detected. Both REEm (mean ± SD, 1579 ± 324 kcal/d) and REEp (1585 ± 316 kcal/d) were also highly correlated (r values = 0.85 to 0.98; p values < 0.001) and provided similar group values to REE estimated by the Harris‐Benedict equations (1597 ± 279 kcal/d) and Wang's composite fat‐free mass–based REE equation (1547 ± 248 kcal/d). New insights into the sources and distribution of REE were provided by analysis of the demonstration groups.Discussion: This approach offers a new practical and educational opportunity to examine REE in subject groups using modeling strategies that reveal the magnitude and distribution of fundamental somatic heat‐producing units.
Effect of Changes in Fat Distribution on the Rates of Change of Insulin Response in Children
Authors: Huang Terry T.‐K. , Johnson Maria S. , Gower Barbara A. , Goran Michael I. 
Published: April 2008

AbstractObjective: To develop mixed models for examining longitudinal associations between rates of change in visceral, subcutaneous abdominal, and total body fat with rates of change in fasting insulin (FI) and insulin sensitivity (SI) over 3 years in children.Research Methods and Procedures: Seventy‐seven children (mean age, 8.3 years at baseline) from Birmingham, Alabama, with three or more annual measures of FI and SI were included. Abdominal fat was measured by computed tomography, and total body fat and lean tissue mass were measured by DXA. Mixed models examined the longitudinal associations between the baseline level/rate of change of different fat compartments and the rate of change in FI or SI.Results: An annual increase of ∼5% in FI was associated with 1 cm2/yr of visceral fat gain per year (p < 0.05), independent of subcutaneous abdominal fat. A 1‐cm2 difference in initial subcutaneous abdominal fat was associated with an ∼0.2% increase per year in FI (p < 0.02), independent of visceral fat. None of the rates of change in any of the fat measures was associated with the rate of change of SI.Discussion: The rate of change in visceral fat was positively associated with the rate of change in FI, independent of increasing subcutaneous abdominal fat; however, subcutaneous abdominal fat may be more predictive of the rate of change of FI than visceral or total fat. Therefore, growth‐related increases in abdominal fat, particularly subcutaneous abdominal fat, may contribute to accelerating increases in FI, but have no effect on SI.
Plasma Adiponectin Levels Are Not Associated with Fat Oxidation in Humans
Authors: Stefan Norbert , Vozarova Barbora , Funahashi Tohru , Matsuzawa Yuji , Ravussin Eric , Weyer Christian , Tataranni P. Antonio 
Published: April 2008

AbstractObjective: To test the hypothesis that low adiponectin is associated with low fat oxidation in humans.Research Methods and Procedures: We measured plasma adiponectin concentrations in 75 healthy, nondiabetic Pima Indians (age, 28 ± 7 years; 55 men and 20 women; body fat, 29.7 ± 7.5%) and 18 whites [(age, 33 ± 8 years; 14 men and 4 women; body fat, 28.2 ± 10.8% (means ± SD)] whose body composition was measured by DXA and 24‐hour energy expenditure (24‐hour EE) by a respiratory chamber. Respiratory quotient (an estimate of whole‐body carbohydrate/lipid oxidation rate) was calculated over 24 hours (24‐hour RQ).Results: Before correlational analyses, waist‐to‐thigh ratio (WTR) and percentage of body fat (PFAT) were adjusted for age, sex, and race; 24‐hour EE was adjusted for fat mass and fat‐free mass, and 24‐hour RQ were adjusted for energy balance. Plasma adiponectin concentrations were negatively correlated with WTR (r = −0.42, p < 0.0001) and PFAT (r = −0.46, p < 0.0001). There was no correlation between plasma adiponectin concentrations and 24‐hour RQ, (r = 0.09, p = 0.36) before or after adjustment for PFAT (r = 0.001, p = 0.99, respectively, partial correlation), and no correlation was found between plasma adiponectin concentrations and 24‐hour EE (r = −0.12, p = 0.27).Discussion: Our cross‐sectional data do not suggest physiological concentrations of fasting plasma adiponectin play a role in the regulation of whole‐body fat oxidation or energy expenditure in resting conditions. Whether administration of adiponectin to individuals with low levels of this hormone will increase their fat oxidation rates/energy expenditure remains to be established.
Obesity and Long‐Term Clinical and Economic Outcomes in Coronary Artery Disease Patients
Authors: Eisenstein Eric L. , Shaw Linda K. , Nelson Charlotte L. , Anstrom Kevin J. , Hakim Zafar , Mark Daniel B. 
Published: April 2008

AbstractObjective:Obesity is an important risk factor for coronary artery disease (CAD); however, its effect on acute coronary syndrome (ACS) patients’ long‐term clinical and economic outcomes has not been quantified. We assessed the impact of increasing body mass index (BMI) on 10‐year outcomes for ACS patients.Research Methods and Procedures:ACS patients with significant CAD receiving an initial cardiac catheterization at Duke University Medical Center between 1986 and 1997 were included. Patients with a BMI < 18.5 kg/m2were excluded; the remaining patients were classified by BMI as normal, overweight, obese, or very obese. Medical costs were estimated from a prior ACS clinical trial with costs adjusted to 1997 dollars and discounted at 3% per annum.Results:There were 9405 patients with data available for analysis. Follow‐up was complete on >95% of patients. Patients who were obese at baseline increased from 20% to 33% between 1986 and 1997. Increased BMI was associated with younger age, multi‐morbidity, and less severe CAD at baseline. It was also associated with more clinical events, higher cumulative inpatient medical costs, and significant differences in unadjusted survival at 10 years. However, it was not associated with differences in 10‐year survival after adjusting for baseline characteristic differences.Discussion:Obese ACS pateints are younger and are hospitalized more frequently during the first 10 years of their illness than are non‐obese patients. They also incur higher cumulative inpatient medical costs, especially the very obese. These findings highlight the opportunities for therapeutic benefit that aggressive weight management and secondary prevention may provide this population.
Bupropion SR vs. Placebo for Weight Loss in Obese Patients with Depressive Symptoms
Authors: Jain Adesh K. , Kaplan Roy A. , Gadde Kishore M. , Wadden Thomas A. , Allison David B. , Brewer Edwin R. , Leadbetter Robert A. , Richard Nathalie , Haight Barbara , Jamerson Brenda D. , Buaron Kathleen S. , Metz Alan 
Published: April 2008

AbstractObjective: This randomized, double‐blind, placebocontrolled study evaluated the efficacy and tolerability of bupropion sustained‐release (bupropion SR) in reducing weight and depressive symptoms in obese adults.Research Methods and Procedures: Obese adults (body mass index, 30 to 44 kg/m2) not currently meeting criteria for major depression but with depressive symptoms (Beck Depression Inventory score 10–30) received bupropion SR 300 mg/d or placebo for 26 weeks with a 500 kcal/d‐deficit diet. Patients who lost <5% of baseline weight at week 12 had bupropion SR dosage or placebo increased to 400 mg/d in a blinded fashion.Results: The bupropion SR group (n = 193) lost an average of 4.4 kg (4.6% of baseline weight) vs. 1.7 kg (1.8% of baseline weight) on placebo (n = 191, p < 0.001, last‐observation‐carried‐forward analysis). More patients in the bupropion SR group than in the placebo group (40% vs. 16% of intent‐to‐treat sample, 50% vs. 28% of completers, respectively) lost at least 5% of baseline weight (p < 0.05 at week 4, p < 0.001 at weeks 6 to 26). The percentage of patients reporting ≥50% decrease in depressive symptoms did not differ between groups, but depressive symptoms improved more with bupropion SR than with placebo among patients with a history of major depression (p < 0.05, weeks 4 to 26). In the sample as a whole, improvement in depressive symptoms was related to weight loss of ≥5% regardless of treatment (p < 0.0001). Bupropion SR was well‐tolerated.Discussion: Bupropion SR in combination with a 500 kcal/d‐deficit diet facilitated weight loss. Weight loss of ≥5% may improve mood in obese patients with depressive symptoms.
Relationship between Obesity and Health‐Related Quality of Life in Men
Authors: Yancy William S. , Olsen Maren K. , Westman Eric C. , Bosworth Hayden B. , Edelman David 
Published: April 2008

AbstractObjective:Few studies examining the relationship between obesity and health‐related quality of life (HRQOL) have used a medical outpatient population or demonstrated a relationship in men. Furthermore, most studies have not adequately considered comorbid illness. The goal of this study was to examine the relationship between body mass index (BMI) and HRQOL in male outpatients while considering comorbid illness.Research Methods and Procedures:This cross‐sectional study examined 1168 male outpatients from Durham Veterans’ Affairs Medical Center. Multiple linear regression was used to examine the relationship of BMI with each subscale from the Medical Outcomes Study Short Form 36 while adjusting for age, race, comorbid illness, depression, and physical activity.Results:Participants had a mean age of 54.7 ± 5.6 years; 69% were white and 29% were African American. The distribution for BMI was as follows: 18.5 to <25 kg/m2(21%), 25 to <30 kg/m2(43%), 30 to <35 kg/m2(25%), 35 to <40 kg/m2(8%), and ≥40 kg/m2(3%). Mean Short Form 36 subscale scores were lower than U.S. norms by an average of 27%. Individuals with BMI ≥40 kg/m2had significantly lower scores compared with normal weight individuals on the Role‐Physical and Vitality subscales. On the Physical Functioning and Physical Component subscales, lower scores were observed at BMI ≥35 kg/m2. On the Bodily Pain subscale, lower scores were observed at BMI ≥25 kg/m2.Discussion:An inverse relationship between BMI and physical aspects of HRQOL exists in a population of male outpatients. Increased BMI was most prominently associated with bodily pain; this relationship should receive more attention in clinical care and research.
The Glucocorticoid Receptor Gene and Its Association to Metabolic Syndrome
Authors: Rosmond Roland 
Published: April 2008

AbstractIn recent decades, there has been an increasing interest in the role of endogenous glucocorticoids such as cortisol in the pathogenesis of metabolic syndrome. Studies in humans have suggested a positive association between obesity, hypertension, and insulin resistance, with alleles at the glucocorticoid receptor (GR) gene. For instance, the BclI polymorphism within the intron upstream of GR exon 2 has been associated with cardiovascular risk factors such as visceral obesity, hypertension, insulin resistance, and elevated cortisol concentrations. However, the location of the BclI polymorphism is not known, and the variant has so far not been compared with the wild‐type receptor for its ability to be activated by glucocorticoids. Although several other mutations in the GR gene have been postulated as being relevant to the progression to type 2 diabetes and cardiovascular diseases, conflicting results makes it difficult to determine exactly what effect these GR variations have on metabolic syndrome incidence and progression. Further studies focusing on the most compelling GR mutations might offer a better understanding of metabolic syndrome pathogenesis and progression, aiding in the development of more effective treatments for this condition.
Resistin and Adiponectin Expression in Visceral Fat of Obese Rats: Effect of Weight Loss
Authors: Milan Gabriella , Granzotto Marnie , Scarda Alessandro , Calcagno Alessandra , Pagano Claudio , Federspil Giovanni , Vettor Roberto 
Published: April 2008

AbstractObjective: Obesity‐related insulin resistance is closely associated with visceral fat accumulation. Several adipocyte‐secreted molecules have been implicated in the development of type 2 diabetes, among them, the recently discovered adiponectin and resistin proteins. Some of these adipocytokines are also present in the immune system, thus suggesting an intriguing functional connection.Research Methods and Procedures: We determined adiponectin and resistin expressions in visceral (VAT) and subcutaneous adipose tissue of lean and obese Zucker (fa/fa) rats using reverse‐transcription polymerase chain reaction. Moreover, we analyzed the variations after body‐weight reduction in food‐restricted obese rats.Results: Resistin and adiponectin expression was significantly lower in VAT of genetically obese in comparison with lean rats; no differences were observed when subcutaneous adipose tissues of the same animals were compared. Weight loss resulted in an increase of adiponectin expression in VAT, whereas a further significant decrease in resistin mRNA level was observed. Resistin is also present and equally expressed in splenocytes of lean and obese rats.Discussion: Adiponectin and resistin are down‐regulated in VAT of obese rats. Adiponectin expression is restored to normal levels after body‐weight reduction, supporting its link with obesity‐related insulin resistance. On the contrary, the further decrease of resistin mRNA after weight loss does not support the hypothesis that resistin may play a causative role in insulin resistance in obese rats. Moreover, we demonstrated the presence of resistin in immunocompetent cells in both humans and rats, thus adding another factor to the list of molecules that adipose tissue shares with the immune system.
Reduction of Plasma Leptin Concentrations by Arginine but Not Lipid Infusion in Humans
Authors: Stingl Harald , Raffesberg Wolfgang , Nowotny Peter , Waldhäusl Werner , Roden Michael 
Published: April 2008

AbstractObjective: We examined short‐term effects of arginine infusion on plasma leptin in diabetic and healthy subjects.Research Methods and Procedures: Arginine stimulation tests were performed in C‐peptide negative type 1 [DM1; hemoglobin A1c; 7.3 ± 0.3%], hyperinsulinemic type 2 diabetic (DM2; 7.6 ± 0.7%), and nondiabetic subjects (CON; 5.4 ± 0.1%).Results: Fasting plasma leptin correlated linearly with body mass index among all groups (r = 0.61, p = 0.001). During arginine infusion, peak plasma insulin was lower in DM1 than in DM2 (p < 0.05) and CON (p < 0.01). Plasma leptin decreased within 30 minutes by ∼11% in DM1 (p < 0.001), DM2 (p < 0.01), and CON (p < 0.005), slowly returning to baseline thereafter. Plasma free fatty acids (FFAs) were higher in DM1 (0.6 ± 0.1 mM) and DM2 (0.6 ± 0.1 mM) than in CON (0.4 ± 0.1 mM, p < 0.05) and transiently declined by ∼50% (p < 0.05) at 45 minutes in all groups before rebounding toward baseline. To examine the direct effects of FFAs on plasma leptin, we infused healthy subjects with lipid/heparin and glycerol during fasting, and somatostatin‐insulin (∼35 pM) ‐glucagon (∼90 ng/mL) clamps were performed. In both protocols, plasma leptin continuously declined by ∼25% (p < 0.05) during 540 minutes without any difference between the high and low FFA conditions.Discussion: Arginine infusion transiently decreased plasma leptin concentrations both in insulin‐deficient and hyperinsulinemic diabetic patients, indicating a direct inhibitory effect of the amino acid but not of insulin or FFAs.
Dietary Restraint and Stress‐Induced Snacking in Youth
Authors: Roemmich James N. , Wright Suzanne M. , Epstein Leonard H. 
Published: April 2008

AbstractObjective: To determine whether dietary restraint modifies stress‐induced eating in youth.Research Methods and Procedures: Snacking was measured in boys (9.5 ± 0.3 years) and girls (9.0 ± 0.3 years), with and without dietary restraint, across a control day after reading children's magazines and/or coloring, and on a stress day after giving a videotaped speech, with order of conditions counterbalanced. Children were divided into four groups based on dietary restraint and changes in perceived stress: low‐restraint/low‐reactive (n = 9), low‐restraint/high‐reactive (n = 13), high‐restraint/low‐reactive (n = 10), and high‐restraint/high‐reactive (n = 8). Body composition was estimated by skinfolds.Results: Energy intake of snack foods was influenced differently by dietary restraint and stress reactivity in the stress and control conditions (p < 0.01). After being stressed, low‐restraint/low‐reactive children ate fewer snacks and high‐restraint/high‐reactive children ate more snacks compared with the control condition. After covarying for percentage of body fat, the interactions remained (p < 0.01). Girls ate less than boys (p < 0.001), but sex did not influence eating in control and stress conditions.Discussion: Dietary restraint occurs in children and may influence the effect of stress on eating. Interpersonal stress decreases snacking in low dietary restrained youth but increases snacking in high dietary restrained children, perhaps because of stress‐induced disinhibition.