bluuebunny/crossref_metadata_2025 huggingface dataset:
QTc Interval (Cardiac Repolarization): Lengthening After Meals
Authors: Nagy David , DeMeersman Ronald , Gallagher Dympna , Pietrobelli Angelo , Zion Adrienne S. , Daly Deborah , Heymsfield Steven B.
Published: September 2012

NAGY, DAVID, RONALD DeMEERSMAN, DYMPNA GALLAGHER, ANGELO PIETROBELLI, ADRIENNE S ZION, DEBORAH DALY, STEVEN B HEYMSFIELD. QTc interval (cardiac repolarization): lengthening after meals.

Weight reduction, either by dietary or surgical means, is associated with prolongation of the heart rate corrected QT interval (QTc=QT/R‐R0–5 and, on occasion, sudden death. Screening subjects with obesity before weight loss for prolonged QTc intervals is an accepted practice, although at present, there are no guidelines for whether subjects should be fasting before electrocardiogram (EKG) evaluation. The aim of this study was to test the hypothesis that EKG QTc interval duration is independent of meal ingestion. The hypothesis was tested in 11 healthy subjects who ingested a 500‐kcal formula meal. A small decrease in absolute QT interval and a steady decline in R‐R interval were observed for up to 60 minutes after formula ingestion. The QTc interval increased above baseline at 15 minutes (p<0. 007) after meal, a change that persisted for the 1‐hour postmeal observation period. Spectral analysis of EKG R‐R intervals (low‐/high‐frequency amplitude ratio) indicated a change in cardiac autonomic flow after meal ingestion. The QTc interval did not lengthen and R‐R low‐/highfrequency amplitude ratio remained unchanged in eight subjects evaluated in a similar manner but in whom isovolumic amounts of water replaced the meal. These observations suggest that (1) cardiac repolarization changes with fasting and feeding, (2) the QTc interval is influenced by meal intake, and (3) the autonomic nervous system may play a role in meal‐related QTc changes. These findings have implications for the evaluation of patients with obesity before starting and during weight loss treatment.
The Thermic Effect of Food and Obesity: A Critical Review
Authors: de Jonee Lilian , Bray George A.
Published: September 2012

DE JONGE, LILIAN, GEORGE BRAY. The thermic effect of food and obesity: A critical review.

This review has examined the factors that influence the thermic effect of food (TEF) by evaluating 49 studies that have compared subjects who are obese with those who are lean. Meal size, meal composition, the nature of the previous diet, insulin resistance, physical activity, and ageing influence TEF. In the studies of individuals who are obese or lean, of those who used intravenous glucose infusions, all but one found an impaired thermic response. A total of 29 out of 49 studies of individuals of normal weight or with obesity were identified where there was no difference in age between the groups, and where the subjects who were “overweight” were clearly obese. Of these 29, 22 reported a statistically significant reduction in TEF, 3 studies were not designed to look primarily at the effect of obesity on TEF, and the other 4 may not have had sufficiently palatable meals. From this review, we conclude that the reduction of TEF in obesity is related to the degree of insulin resistance, which may be influenced by a low level of sympathetic activity.
Parity‐Associated Body Weight: Modification by Sociodemographic and Behavioral Factors
Authors: Wolfe Wendy S. , Sobal Jeffery , Olson Christine M. , Frongillo Edward A.
Published: September 2012

This research examines the association between parity and body weight and how this relationship is modified by sociodemographic and behavioral factors. Using multiple linear regression analysis, the study assessed the relationship between parity and relative body weight (as Body Mass Index, BMI) and how this relationship interacts with seven sociodemographic and seven behavioral factors in a national sample of 5,707 women from the Second National Health and Nutrition Examination (NHANES II) survey. After adjusting for sociodemographic factors, the amount of weight associated with parity averaged about 0.5 kg per child. However, parity‐associated weight differed by sociodemographic and behavioral factors, and was much larger in some subgroups. Among 18–45 year olds, the amount of weight associated with parity was greater in blacks than in whites, less in employed than unemployed white women but greater in employed than unemployed black women, less in smokers than nonsmokers, less in those with a high level of recreational exercise, and differed with the level of nonrecreational physical activity depending on race. Among 46–74 year olds, the amount of weight associated with parity was greater in married than unmarried women, and less in those who were active outside of recreation versus those who were less active. These results suggest that sociodemographic and behavioral variables modify the relationship between parity and body weight, and provide insight for identifying women who are at risk for having greater BMI with higher parity. This information may be applicable to the targeting and design of interventions to prevent postpartum weight retention.
Construct Validity of the Impact of Weight on Quality of Life Questionnaire
Authors: Kolotkin Ronette L. , Head Susan , Brookhart Alan
Published: September 2012

KOLOTKIN, RONETTE L, SUSAN HEAD, ALAN BROOKHART. Construct validity of the Impact of Weight on Quality of Life questionnaire.

The Impact of Weight on Quality of Life questionnaire (IWQOL) is a 74‐item self‐report, condition‐specific instrument that (1) assesses the effect of weight on quality of life in eight key areas, and (2) may be used as a treatment outcome measure and/or an evaluation tool for healthcare policy makers and third‐party payers. This study explores IWQOL construct validity and provides new information on internal consistency, treatment effects, and differences between men and women. IWQOL total scores correlated highly with other measures of overall quality of life, and subscale scores correlated well with counterparts in the assessment battery. Internal consistency estimates for the IWQOL scales generally were high. For the women, 4‐week participants, and the total sample, pretreatment‐posttreatment differences were significant for all IWQOL scales and total score. For men, treatment differences were significant for the total score and all subscales except for Work and Mobility. Treatment differences for 2‐week participants were significant for all scales except for Work. Consistent with previous IWQOL study results, the Comfort With Food scale scores reflected more discomfort at posttreatment as compared with pretreatment. The IWQOL, already translated into French and Italian, currently is demonstrating clinical and research utility as a quality‐of‐life outcome measure for clinical trials of antiobesity drugs and surgical treatments for patients with obesity.
Association of Adenovirus Infection with Human Obesity
Authors: Dhurandhar Nikhil V. , Kulkarni Pushpa R. , Ajinkya Sharad M. , Sherikar Abhaya A. , Atkinson Richard L.
Published: September 2012

DHURANDHAR, NIKHIL V, PUSHPA R KULKARNI, SHARAD M AJINKYA, ABHAYA A SHERIKAR, RICHARD L ATKINSON. Association of adenovirus infection with human obesity.

We previously reported that chickens infected with the avian adenovirus SMAM‐1 developed a unique syndrome characterized by excessive intra‐abdominal fat deposition accompanied by paradoxically low serum cholesterol and triglyceride levels. There have been no previous reports of avian adenoviruses infecting humans. We screened the serum of 52 humans with obesity in Bombay, India, for antibodies against SMAM‐1 virus using the agar gel precipitation test (AGPT) method. Bodyweights and serum cholesterol and triglyceride levels were compared in SMAM‐1‐positive (P‐AGPT) and SMAM‐1‐negative (N‐AGPT) groups. Ten subjects were positive for antibodies to SMAM‐1, and 42 subjects did not have antibodies. The P‐AGPT group had a significantly higher bodyweight (p<0.02) and body mass index (p<0.001) (95.1 ± 2.1 kg and 35.3 ± 1.5 kg/m2, respectively) compared with the N‐AGPT group (80.1 ± 0.6 kg and 30.7 ± 0.6 kg/m2, respectively). Also, the P‐AGPT group had significantly lower serum cholesterol (p<0.02) and triglyceride (p<0.001) values (4.65 mmol/L and 1.45 mmol/L, respectively) compared with the N‐AGPT group (5.51 mmol/L and 2.44 mmol/L, respectively). Two subjects positive for SMAM‐1 antibodies had antibodies against each others' serum, suggesting the presence of antigens in one or both. When these two serum samples were inoculated into chicken embryos, macroscopic lesions compatible with SMAM‐1 infection developed. The inoculation of serum from N‐AGPT subjects did not produce such lesions. The presence of increased obesity, antibodies to SMAM‐1, reduced levels of blood lipids, and viremia that produces a typical infection in chicken embryos suggests that SMAM‐1, or a serologically similar human virus, may be involved in the cause of obesity in some humans.
Food Intake in Prader‐Willi Syndrome and Controls with Obesity After Administration of a Benzodiazepine Receptor Agonist
Authors: Fieldstone Annette , Zipf William B. , Sarter Martin F. , Berntson Gary G.
Published: September 2012

Benzodiazepine receptor (BZR) agonists, used extensively for their anxiolytic effects, have been shown to increase food intake in many mammalian species. Little information, however, is available on the effects of BZR agonists on feeding behaviors of humans. Food intake was evaluated in a 60‐minute free‐feeding standardized test after the acute administration of the BZR agonist chlordiazepoxide (CDP, Librium; 5 mg or 20 mg) or placebo. Subjects were 12 individuals with the Prader Willi syndrome (PWS), a disorder characterized by extreme hyperphagia and morbid obesity, and 11 controls with obesity. PWS subjects showed the characteristic hyperphagia associated with the appetite disorder, consuming more than six times as many sandwiches as controls with obesity. Results revealed no significant effect of either dose of CDP on the food intake of either group. Serum assays revealed that dose‐dependent, clinically effective levels of CDP and active metabolites were achieved. These results suggest that acute administration of the BZR agonist CDP, at the therapeutic levels used, may not increase food intake in populations with obesity. However, the chronic effects of CDP on appetite in human populations still need to be explored.
Metformin Decreases Food Consumption and Induces Weight Loss in Subjects with Obesity with Type II Non‐Insulin‐Dependent Diabetes
Authors: Lee Amy , Morley John E.
Published: September 2012

Metformin often promotes weight loss in patients with obesity with non‐insulin‐dependent diabetes mellitus (NIDDM). The mechanism may be attributed to decreased food intake. This study has tested the effect of metformin on satiety and its efficacy in inducing weight loss. Twelve diet‐treated NIDDM women with obesity were randomly given two dose levels (850 mg or 1700 mg) of metformin or placebo at 0800 for three consecutive days followed by a meal test on the third day on three occasions using a 3times3 Latin square design. The number of sandwich canapes eaten in three consecutive 10‐minute periods beginning at 1400 hours was used to quantitate food intake, and the level of subjective hunger was rated just before the sandwich meal with a linear analogue hunger rating scale at 1400 after a 6‐hour fast. The prior administration of metformin produced a reduction in calorie intake after each of the two doses of metformin treatment. The 1700‐mg metformin dose had the most marked appetite suppressant action. Similarly, hunger ratings were significantly lowered after metformin, and the effect was most pronounced after the administration of 1700 mg of metformin. To assess the efficacy of metformin in reducing bodyweight, 48 diet‐treated NIDDM women with obesity who had failed to lose weight by diet therapy were first placed on a 1200‐kcal ADA (American Diabetes Association) diet before being randomized to receive either metformin (850 mg) or placebo twice daily in a double‐blind fashion for 24 weeks. A 4‐week single‐blind placebo lead‐in period preceded and a 6‐week single‐blind placebo period followed the 24‐week double‐blind treatment period. Subjects treated with metformin continued to lose weight throughout 24 weeks of treatment; their mean maximum weight loss was 8 kg greater than that of the placebo group, with corresponding lower HbA1C and fasting blood glucose levels at the end of the active treatment period. These results indicate that metformin decreases calorie intake in a dose‐dependent manner and leads to a reduction in bodyweight in NIDDM patients with obesity.
Effect of Chronic Central Administration of Glucagon‐Like Peptide‐1 (7–36) Amide on Food Consumption and Body Weight in Normal and Obese Rats
Authors: Davis Harry R. , Mullins Deborra E. , Pines Jesse M. , Hoos Lizbeth M. , France Constance F. , Compton Douglas S. , Graziano Michael P. , Sybertz Edmund J. , Strader Catherine D. , Van Heek Margaret
Published: September 2012

Glucagon‐like peptide (7–36) amide (GLP‐1) acutely inhibits food and water consumption in rats after intrace‐rebroventricular (icv) administration. To assess the potential for desensitization of these effects, we investigated the effects of chronic icv administration of GLP‐1 on food consumption and body weight in Sprague‐Dawley (SD) rats and Zucker (fa/fa) obese rats. In vitro functional densensitization of the GLP‐1 receptor was not observed after overnight exposure of Rin m5F insulinoma cells to GLP‐1 at concentrations up to 10 nM. Administration of GLP‐1 to SD rats (30 ug icv twice a day for 6 days) resulted in significant reductions in 24‐hour food consumption each day (25 ±1%). Continuous icv infusion of GLP‐1 for 7 and 14 days significantly inhibited cumulative food consumption and reduced body weight in SD rats. In the genetically obese Zucker rat, chronic dosing with GLP‐1 (30 ug icv) once a day for 6 days caused significant reductions in food consumption each day and a reduction in body weight. These results indicate that the GLP‐1 pathways in the central nervous system controlling food consumption do not desensitize after chronic exposure to GLP‐1 and suggest that agonists of the central GLP‐1 receptor may be effective agents for the treatment of obesity.
Blood Pressure in Adolescence and Early Adulthood Related to Obesity and Birth Size
Authors: Berkey Catherine S. , Gardner Jane , Colditz Graham A.
Published: September 2012

Objective: Obesity is an established risk factor for higher systolic (SBP) and diastolic (DBP) blood pressure in adolescence and early adulthood, but birth size may also have a role. We analyzed the effects of adolescent and adult obesity and birth size on BP in the young adult.

Research Methods and Procedures: In a prospective longitudinal study, anthropometric measurements were obtained at birth on 67 boys and 67 girls bom in Boston. Their body mass indices (BMI) and BP were recorded 17 years and 30 years later.

Results: For women, adolescent and early adult obesity appeared to be the stronger determinants of higher BP, although smaller head and chest circumferences at birth may also be related. We found some evidence of birth (ponderal index [PI] and head circumference) anthropometric influences on age 17 BP levels in boys. By age 30, body mass variables were the dominant predictors of male BP levels. Female BMI at age 17 was positively correlated with birth adiposity (PI), but BMI at 30 was related only to age 17 BMI. Similarly, male BMI at 17 years was higher for those who weighed more at birth, but BMI at 30 years was again related only to age 17 BMI.

Discussion: We conclude that adult weight and weight gain are the major determinants of adult BP.
Relationship Between Hunger‐Satiety Feelings and Various Metabolic Parameters in Women with Obesity During Controlled Weight Loss
Authors: Heini Adrian F. , Kirk Katharine A. , Lara‐Castro Cristina , Weinsier Roland L.
Published: September 2012

Objective: Satiety plays an important role in weight control. The meaning of fasting hormone levels and satiety feelings, and how post‐absorptive changes after meals high in carbohydrate regulate appetite remains to be demonstrated.

Research Methods and Procedures: Prospective metabolic study with 25 non‐diabetic obese women at the Energy Metabolism Research Unit of the Department of Nutrition Sciences, University of Alabama at Birmingham. We analyzed fasting and postprandial ratings of hunger‐satiety and values of various metabolic parameters (serum glucose and insulin, plasma cholecystokinin, respiratory quotient) during controlled weight loss. The postprandial measures were assessed following a test meal providing 320 kcal and yielding a food quotient of 0.89.

Results: In the fasting state, there was no correlation between hunger‐satiety ratings and any of the measured metabolic parameters. Under postprandial conditions, satiety was positively related to glucose (p = 0.002) and insulin (p = 0.002) responses to the test meal. In multivariate analysis including glucose, insulin, cholecystokinin, hunger‐satiety ratings and respiratory quotient, insulin was the only independent predictor of satiety in the postprandial state.

Discussion: These data suggest an association between the endogenous insulin response and feelings of postprandial satiety. Insulin's satiation properties, which could well be mediated by other hormones, may represent a primary factor of food intake regulation after meals relatively high in carbohydrate.
Clinic‐Based vs. Home‐Based Interventions for Preventing Weight Gain in Men
Authors: Leermakers Elizabeth A. , Jakicic John M. , Viteri Jackie , Wing Rena R.
Published: September 2012

Objective: Weight gain occurs frequently in men aged 25–40. This study compared the effectiveness of a clinic‐based and a home‐based intervention with a no‐treatment control group in preventing this weight gain.

Research Methods and Procedures: Men (n = 67)—aged 25 to 40, sedentary, with a body mass index of 22 to 30, recruited from the University of Pittsburgh—were randomly assigned to 4‐month treatments focused on increasing aerobic exercise and reducing fat intake through a clinic‐based (CB) or a home‐based (HB) program, or to a de‐layed‐treatment control group. Subjects were reassessed at 4 months.

Results: Adherence and outcome did not differ significantly between the CB and HB programs, except that CB subjects recorded their food intake more frequently, and a greater number of CB subjects achieved a total of 120 miles of exercise over the 4 months. Subjects in the two intervention conditions combined lost significantly more weight (‐1.6 ± 2.5 kg) than control subjects, who gained 0.2 ±1.9 kg (p<0.01); this effect of treatment was seen primarily in men with a body mass index of 27 to 30 (‐2.7 kg for CB and HB combined vs. +1.5 kg for control). Treated subjects also had somewhat greater improvements in body composition, aerobic fitness, and weekly energy expenditure than controls, although these differences did not reach significance. Discussions: Both CB and HB intervention show promise in preventing weight gain in young men, especially in those who are slightly overweight. Larger studies, using more representative samples of young men, appear warranted.
Monkey Leptin Receptor mRNA: Sequence, Tissue Distribution, and mRNA Expression in the Adipose Tissue of Normal, Hyperinsulinemic, and Type 2 Diabetic Rhesus Monkeys
Authors: Hotta Kikuko , Gustafson Thomas A. , Ortmeyer Heidi K. , Bodkin Noni L. , Hansen Barbara C.
Published: September 2012

Objective: We have cloned the rhesus monkey leptin receptor and examined its mRNA expression levels in the adipose tissue of monkeys to investigate the regulation of gene expression of the leptin receptor.

Research Methods and Procedures: Monkey leptin receptor cDNA was cloned by reverse transcriptase‐polymerase chain reaction (RT‐PCR). Tissue distribution of monkey leptin receptor was examined by Northern blot analysis and RT‐PCR. The mRNA levels of monkey leptin receptor in adipose tissue of normal (n=10), hyperinsulinemic obese (n = 8), and type 2 diabetic monkeys (n = 8) were measured by quantitative RT‐PCR.

Results: Monkey leptin receptor cDNA had at least two alternatively spliced isoforms (long and short forms). The long form of the leptin receptor mRNA was expressed relatively highly in liver, adipose tissue, hypothalamus, and choroid plexus, whereas the total leptin receptors were expressed in every tissue examined. The mRNA levels of the long form of the leptin receptor in adipose tissue were not correlated to body weight, fasting plasma insulin, plasma glucose, or plasma leptin levels. The mRNA levels of the long form of the leptin receptor were highly correlated to that of the total leptin receptor (long and short form).

Discussion: The long form of leptin receptor mRNA existed in adipose tissue as well as in liver and hypothalamus, suggesting that the leptin receptor in adipose tissue may be functional in adipose tissue. The expression of the leptin receptor mRNA in adipose tissue is not affected by obesity, hyperinsulinemia, or diabetes.
Effect of Age on Protein Conservation during Very‐Low‐Energy Diet in Obese Sprague‐Dawley Rats
Authors: Johnson Julia A. , Yu Choon‐Hie , Yang Mei‐Uih , Pi‐Sunyer F. Xavier
Published: September 2012

JOHNSON, JULIA A, CHOON‐HIE YU, MEI‐UIH YANG, F. XAVIER PI‐SUNYER. Effect of age on protein conservation during very‐low‐energy diet in obese Sprague‐Dawley rats. Obes. Res. 1998;6:448‐157.

Objective: To examine the effect of age on body protein losses occurring during severe energy restriction in obesity.

Research Methods and Procedures: Weanling (young) Sprague‐Dawley rats (YR) were fed a high fat (35% energy) diet (HFD) until mean body weight approached that of a group of chowfed retired breeder (aged) rats (AR). Both groups were then fed HFD for an additional 2 weeks, after which selected controls from YR and AR groups were killed for baseline carcass analysis. Remaining rats were fed a very‐low‐energy diet (VLED, 33% kcal of HFD) for 3 weeks and then killed for carcass analysis.

Results: YR had greater fat stores before VLED, and lost proportionately more fat and less protein during VLED than did AR. Weight loss composition during VLED was 66.7% fat, 11.1% protein, and 22.2% water in YR, and 39.4% fat, 26.2% protein, and 34.3% water in AR. Greater YR fat loss during VLED* (70.6 ± 30.4 vs. 32.6 ± 29.1 g in AR; mean ± SD) was paralleled by significantly larger decreases in epididymal and retroperitoneal fat pad weights, mean adipocyte size, and lipoprotein lipase activity. Greater protein loss in AR (21.6 ± 13.9 g vs. 11.8 ± 10.7 g in YR) coincided with larger decreases in visceral organ weights and serum thyroxine and triiodothyronine. Energy expenditure changes during VLED were similar between groups.

Discussion: Dietary obese young rats appear better able than aged rats to conserve body protein while losing body fat during severe energy restriction.
What Is the Economic Case for Treating Obesity?
Authors: Wolf Anne M.
Published: September 2012

From both societal and payer perspectives, the economic effect of obesity in the United States is substantial, estimated at approximately 6% of our national health expenditure and cost of care in a major health maintenance organization. The number of physician visits related to obesity has increased 88% in a 6‐year period. The morbidity cost (lost productivity) and functional capability of the patient with obesity is increasing rapidly (50% increase in lost productivity, 36% increase in restricted activity, and 28% increase in number of bed‐days). Cost savings of treating obesity are comparable to those of treating other chronic diseases such as coronary heart disease and diabetes. Most studies indicate that most of the direct health care costs of obesity are from type 2 diabetes, coronary heart disease and hypertension. To date, however, there have been no published reports of the cost effectiveness of the medical management of obesity treatment. In conclusion, the cost of obesity is comparable to that of other chronic diseases, yet it receives disproportionately less attention. Cost effectiveness studies need to be initiated promptly.
The Use of Anthropometric and Dual‐Energy X‐ray Absorptiometry (DXA) Measures to Estimate Total Abdominal and Abdominal Visceral Fat in Men and Women
Authors: Clasey Jody L. , Bouchard Claude , Teates C. David , Riblett Jill E. , Thorner Michael O. , Hartman Mark L. , Weltman Arthur
Published: September 2012

CLASEY, JODY L., CLAUDE BOUCHARD, C. DAVID TEATES, JILL E. RIBLETT, MICHAEL O. THORNER, MARK L. HARTMAN, AND ARTHUR WELTMAN. the use of anthropometric and dual‐energy X‐ray absorptiometry (DXA) measures to estimate total abdominal and abdominal visceral fat in men and women. Obes Res.

Objective: A single‐slice computed tomography (CT) scan provides a criterion measure of total abdominal fat (TAF) and abdominal visceral fat (AVF), but this procedure is often prohibitive due to radiation exposure, cost, and accessibility. In the present study, the utility of anthropometric measures and estimates of trunk and abdominal fat mass by dual‐energy X‐ray absorptiometry (DXA) to predict CT measures of TAF and AVF (cross‐sectional area, cm2) was assessed.

Research Methods and Procedures: CT measures of abdominal fat (at the level of the L4‐L5 inter‐vertebral space), DXA scans, and anthropometric measures were obtained in 76 Caucasian adults ages 20–80 years.

Results: Results demonstrated that abdominal sagittal diameter measured by anthropometry is an excellent predictor of sagittal diameter measured from a CT image (r = 0. 88 and 0. 94; Total Error [TE]=4. 1 and 3. 1 cm, for men and women, respectively). In both men and women, waist circumference and abdominal sagittal diameter were the anthropometric measures most strongly associated with TAF (r = 0. 87 to 0. 93; Standard Error of Estimate (SEE) = 60. 7 to 75. 4 cm2) and AVF (r = 0. 84 to 0. 93; SEE = 0. 7 to 30. 0 cm2). The least predictive anthropometric measure of TAF or AVF was the commonly used waist‐to‐hip ratio (WHR). DXA estimates of trunk and abdominal fat mass were strongly associated with TAF (r =. 94 to 0. 97; SEE = 36. 9 to 50. 9 cm2) and AVF (r = 0. 86 to 0. 90; SEE = 4. 9 to 27. 7 cm2).

Discussion: The present results suggest that waist circumference and/or abdominal sagittal diameter are better predictors of TAF and AVF than the more commonly used WHR. DXA trunk fat and abdominal fat appear to be slightly better predictors of TAF but not AVF compared to these anthropometric measures. Thus DXA does not offer a significant advantage over anthropometry for estimation of AVF.
Association of Total and Central Adiposity Measures with Fasting Insulin in a Biracial Population of Young Adults with Normal Glucose Tolerance: the CARDIA Study
Authors: Sidney Stephen , Lewis Cora E. , Hill James O. , Quesenberry Charles P. , Stamm Elizabeth R. , Scherzinger Ann , Tolan Kimberly , Ettinger Bruce
Published: September 2012

SIDNEY, STEPHEN, CORA E. LEWIS, JAMES O. HILL, CHARLES P. QUESENBERRY, JR, ELIZABETH R. STAMM, ANN SCHERZINGER, KIMBERLY TOLAN, AND BRUCE ETTINGER. Association of total and central adiposity measures with fasting insulin in a biracial population of young adults with normal glucose tolerance: the CARDIA study. Obes Res.

Objective: To determine the association of computed tomography (CT)‐measured visceral adipose tissue (AT) and other measures of adiposity with fasting insulin in a biracial (African American and Caucasian) study population of young adults.

Research Methods and Procedures: The study population consisted of 251 young adults with normal glucose tolerance (NGT), ages 28–40 years, who were volunteers from the Birmingham, Alabama, and Oakland, California centers of the Coronary Artery Risk Development in Young Adults (CARDIA) study.

Results: In regression models with total adiposity measures (body mass index or dual‐energy X‐ray absorptiometry‐measured percent fat), visceral AT (measured as a cross‐sectional area in cm2) was generally a stronger predictor of insulin than overall adiposity in all race/gender groups (partial correlation coefficients ranging from 0. 31 to 0. 47) except for black men, in whom the associations were nonsignificant. Partial correlation coefficients between waist circumference and insulin, controlling for percent fat, were nearly identical to those between visceral AT and insulin in women and in white men. Analyses performed on 2060 NGT CARDIA subjects who were not in this study of visceral AT showed significant correlations of waist circumference with insulin in all racelgender groups, including black men, and that black men in the visceral AT study group were significantly leaner than other black male CARDIA subjects.

Discussion: We conclude that visceral AT was associated with fasting insulin in NGT participants in three of the four race/gender groups (black men excepted) and that waist circumference was a good surrogate for visceral AT in examining associations of central adiposity with fasting insulin.
Changes in Self‐Efficacy and Decisional Balance for Exercise among Obese Women in a Weight Management Program
Authors: Pinto Bernardine M. , Clark Matthew M. , Cruess Dean G. , Szymanski Lynda , Pera Vincent
Published: September 2012

PINTO, BERNARDINE M., MATTHEW W. CLARK, DEAN G. CRUESS, LYNDA SZYMANSKI, AND VINCENT PERA. Changes in self‐efficacy and decisional balance for exercise among obese women in a weight management program. Obes Res.

Objective: To assess changes in eating and exercise self‐efficacy and decisional balance for exercise in an obese population enrolled in a multi‐disciplinary weight management program.

Research Method and Procedures: Thirty‐two obese women were assessed at entry and after 12 weeks of treatment.

Results: Participants showed 15% mean weight loss after 12 weeks of treatment. Mean minutes of self‐reported exercise increased by 229%. Participants demonstrated significant improvements in self‐efficacy for both eating and exercise and health parameters but not in decisional balance for exercise adoption.

Discussion: These results may have implications for the practitioner in that self‐efficacy changes occur during successful weight loss, but decisional balance for exercise may not change until individuals enter maintenance. These results imply that practitioners may be advised to shift from confidence building to relapse prevention early on in treatment, and that focusing on strengthening the pros of exercise and reducing the cons of exercise may need to remain constant during treatment.
Body Fat, Resting and Exercise Blood Pressure and the Angiotensinogen M235T Polymorphism: The Heritage Family Study
Authors: Rankinen Tuomo , Gagnon Jacques , Pérusse Louis , Rice Treva , Leon Arthur S. , Skinner James S. , Wilmore Jack H. , Rao D. C. , Bouchard Claude
Published: September 2012

RANKINEN, T., JACQUES GAGNON, LOUIS PÉRUSSE, TREVA RICE, ARTHUR s. LEON, JAMES s. SKINNER, JACK H. WILMORE, D. C. RAO, AND CLAUDE BOUCHARD. Body fat, resting and exercise blood pressure and the angiotensinogen M235T polymorphism: the Heritage family study. Obes Res.

Objective: The association of resting and exercise blood pressure (BP) and fat mass with the angiotensinogen (AGT) M235T polymorphism was investigated in 522 sedentary Caucasian subjects from 99 families.

Research Methods and Procedures: Resting BP was measured on two separate days, three times each day, and the mean of six valid measurements was used. Exercise BP was measured during a cycle ergometer test at a constant power output (50 W). Body composition was derived from underwater weighing and the AGT M235T polymorphism was typed with a polymerase chain reaction‐based method.

Results: Neither resting nor exercise BP was associated with the AGT genotypes. In mothers, the homozygotes for the T allele showed 8. 8 kg and 7. 1 kg greater (p = 0. 017) age‐adjusted body fat mass (FM) than the MM homozygotes and heterozygotes, respectively. Sixty‐nine percent of all TT homozygotes were found in the highest FM tertile, whereas only 16% of the MM homozygotes fell in the same tertile (p = 0. 008). Moreover, a significant interaction was seen between FM and T‐allele carrier status in women with regard to resting diastolic BP (p = 0. 002). Among women with a FM≥24 kg, carriers of the T allele showed a 6. 3 mmHg higher diastolic blood pressure (DBP) than non‐carriers whereas no difference was found in women with a FM less than 24 kg. A similar trend toward an interaction term was evident with resting systolic blood pressure (p = 0. 011) and exercise DBP (p = 0. 012). Body fat was not associated with the AGT polymorphism in fathers or in offspring.

Discussion: These data suggest that the AGT M235T polymorphism is associated with body fatness in women, and that the relationship between DBP and AGT M235T polymorphism is dependent on FM in middle‐aged sedentary normotensive women.
Reduction in Incidence of Diabetes, Hypertension and Lipid Disturbances after Intentional Weight Loss Induced by Bariatric Surgery: the SOS Intervention Study
Authors: Sjöström C. David , Lissner Lauren , Wedel Hans , Sjöström Lars
Published: September 2012

SJÖSTRÖM, c. DAVID, LAUREN LISSNER, HANS WEDEL, and LARS SJÖSTRÖM. Reduction in incidence of diabetes, hypertension and lipid disturbances after intentional weight loss induced by bariatric surgery: the SOS Intervention Study. Obes Res.

Objective: To examine the effect of a large, long standing and intentional weight reduction on the incidence of diabetes, hypertension and lipid disturbances in severely obese individuals as compared to weight‐stable obese controls.

Research Methods and Procedures: The ongoing prospective SOS (Swedish Obese Subjects) intervention consists of a surgically treated group and a matched control group obtaining conventional obesity treatment. This report is based on 845 surgically treated patients and 845 controls (BMI41. 0±4. 6 kg/m2 (mean±standard deviation [S])) followed for 2 years.

Results: Surgically treated patients lost 28±15 kg and controls 0. 5±8. 9 kg (p<0. 0001). Two‐year incidence of hypertension, diabetes, hyperinsulinemia, and lipid disturbances was compared in the two treatment groups. Adjusted odds ratios (95% CI) for the surgically treated group versus controls were 0. 38 (0. 22, 0. 65) for hypertension, 0. 02 (0. 00, 0. 16) for diabetes, 0. 10 (0. 03, 0. 28) for hyperinsulinemia, 0. 10 (0. 04, 0. 25) for hypertriglyceridemia, 0. 28 (0. 16, 0. 49) for low HDL‐cholesterol and 1. 24 (0. 84, 1. 8) for hypercholesterolemia. Compared to controls, the 2‐year recovery rates from hypertension, diabetes, hypo‐HDL, and hypertriglyceridemia were significantly higher in the surgically treated group.

Discussion: Intentional weight loss in the obese causes a marked reduction in the 2‐year incidence of hypertension, diabetes and some lipid disturbances. The results suggest that severe obesity can and should be treated.
Adipocyte Development is Dependent Upon Stem Cell Recruitment and Proliferation of Preadipocytes
Authors: Kras Krystyna M. , Hausman Dorothy B. , Hausman Gary J. , Martin Roy J.
Published: September 2012

KRAS, KRYSTYNA M., DOROTHY B. HAUSMAN, GARY J. HAUSMAN, AND ROY J. MARTIN. Adipocyte development is dependent upon stem cell recruitment and proliferation of preadipocytes. Obes Res.

Objectives: The ability to acquire fat cells persists over the life spans of animals. It is unknown whether adipocyte acquisition is the result of preadipocyte proliferation or stem cell recruitment to become adipocytes. The purposes of these studies were 1) to characterize early differentiation of stromal vascular (S‐V) cells to preadipocytes as it is influenced by insulin, dexamethasone (DEX), and insulin‐like growth factor‐I (IGF‐I); and 2) to determine whether new fat cells arise from stem cell recruitment or preadipocyte proliferation.

Research Methods and Procedures: Freshly isolated S‐V cells from rat inguinal adipose tissues were plated for 24 hours then exposed to serum‐free medium.

Results: Approximately 15% of freshly plated S‐V cells were preadipocytes as determined by a preadipocyte specific marker, AD3. Total cell number and proportion of preadipocytes were significantly greater with 100 nM insulin treatment than with 0, 0. 1, or 1. 0 nM, but IGF‐I treatment at 10 nM resulted in preadipocyte development similar to that with 100 nM insulin treatment. The addition of 5 nM DEX to the 100 nM insulin treatment resulted in a 20% increase in preadipocyte number by day 2 when compared to either treatment alone. 5‐Bromo‐2′‐deoxyuridine treatment suppressed the increased proportion of preadipocytes from days 0–2 in non‐insulin treated cells and prevented the increase typically observed with insulin. A mitosis inhibitor also significantly reduced the proportion of preadipocytes.

Discussion: These results show for the first time that S‐V cells are recruited as preadipocytes and that proliferation of these preadipocytes and early differentiation occur simultaneously.
Neuropeptide Y Expression and Endogenous Leptin Concentrations in a Dietary Model of Obesity
Authors: Lauterio Thomas J. , Davies Michael J. , DeAngelo Mark , Peyser Michael , Lee James
Published: September 2012

LAUTERIO, THOMAS J., MICHAEL J. DAVIES, MARK DEANGELO, MICHAEL PEYSER, AND JAMES LEE. Neuropeptide Y expression and endogenous leptin concentrations in a dietary model of obesity. Obes Res.

Objective: To determine how leptin concentrations and neuropeptide (NPY) are regulated in a model of dietary obesity in relation to relative growth (RG) and relative food consumption (RFC).

Research Methods and Procedures: Sprague—Dawley rats were fed a moderately high‐fat diet for 14 weeks over which time animals diverged into obesity‐prone (OP) and obesity‐resistant (OR) populations. RG rates and RFC were calculated weekly. Following the study, an adiposity index was calculated and arcuate nucleus (ARC) NPY expression was determined by in situ hybridization (ISH) or ribonuclease protection (RPA) assays.

Results: Body weights were greater in OP rats after 2 weeks on the diet compared to OR rats and remained different throughout the study. RG and RFC were greater in OP rats compared to OR rats only during the first 2 weeks of the study. Leptin concentrations rose in both groups during the experiment, but the increase was greater in OP rats than in OR rats. Insulin changes paralleled those for leptin. ARC NPY mRNA expression was not different between OP and OR rats as measured by ISH and RPA.

Discussion: Although NPY expression has been reported to be different initially in OP and OR rats, this difference dissipates following divergence of body weight. RFC and RG data suggest the initial NPY elevation may contribute to increased weight gain of OP rats during the first 2 weeks of the diet. Higher relative leptin concentrations in OP rats may be necessary to normalize differences in adiposity and apparent leptin and insulin resistance of OP rats.
The Yellow Mouse Obesity Syndrome and Mechanisms of Agouti‐Induced Obesity
Authors: Moussa Naïna Moustaïd , Claycombe Kate J.
Published: September 2012

The yellow mouse obesity syndrome is due to dominant mutations at the Agouti locus, which is characterized by obesity, hyperinsulinemia, insulin resistance, hyperglycemia, hyperleptinemia, increased linear growth, and yellow coat color. This syndrome is caused by ectopic expression of Agouti in multiple tissues. Mechanisms of Agouti action in obesity seem to involve, at least in part, competitive melanocortin antagonism. Both central and peripheral effects have been implicated in Agouti‐induced obesity. An Agouti‐Related Protein (AGRP) has been described recently. It has been shown to be expressed in mice hypothalamus and to act similarly to agouti as a potent antagonist to central melanocortin receptor MC4‐R, suggesting that AGRP is an endogenous MC4‐R ligand. Mice lacking MC4‐R become hyperphagic and develop obesity, implying that agouti may lead to obesity by interfering with MC4‐R signaling in the brain and consequently regulating food intake. Furthermore, food intake is inhibited by intracerebro‐ventricular injection of a potent melanocortin agonist and was reversed by administration of an MC4‐R antagonist. The direct cellular actions of Agouti include stimulation of fatty acid and triglyceride synthesis via a Ca2+‐dependent mechanism. Agouti and insulin act in an additive manner to increase lipogenesis. This additive effect of agouti and insulin is demonstrated by the necessity of insulin in eliciting weight gain in transgenic mice expressing agouti specifically in adipose tissue. This suggests that agouti expression in adipose tissue combined with hyperinsulinemia may lead to increased adiposity. The roles of melanocortin receptors or agouti‐specific receptor(s) in agouti regulation of adipocyte metabolism and other peripheral effects remain to be determined. In conclusion, both central and peripheral actions of agouti contribute to the yellow mouse obesity syndrome and this action is mediated at least in part by antagonism with melanocortin receptors and/or regulation of intracellular calcium.
Effects of Obesity and Stable Weight Reduction on UCP2 and UCP3 Gene Expression in Humans
Authors: Vidal‐Puig Antonio , Rosenbaum Michael , Considine Robert C. , Leibel Rudolph L. , Dohm G. Lynis , Lowell Bradford B.
Published: September 2012

VIDAL‐PUIG, ANTONIO, MICHAEL ROSENBAUM, ROBERT C. CONSIDINE, RUDOLPH L. LEIBEL, G. LYNIS DOHM, AND BRADFORD B. LOWELL. Effects of obesity and stable weight reduction on UCP2 and UCP3 gene expression in humans. Obes Res.

Objectives: The molecular determinants of energy expenditure are presently unknown. Recently, two uncoupling protein homologues, UCP2 and UCP3, have been identified. UCP2 is expressed widely, and UCP3 is expressed abundantly in skeletal muscle. Both could be important regulators of energy balance. In this paper, we investigated whether altered UCP2 and UCP3 mRNA levels are associated with obesity or weight reduction.

Research Methods and Procedures: UCP2, UCP3 long and short mRNA levels were examined in skeletal muscle and in white adipose tissue of lean, obese, and weight‐reduced individuals by RNase protection assay.

Results: Expression of UCP2, UCP3S, and UCP3L mRNA in skeletal muscle was similar in lean individuals and in individuals with obesity at stable weight. In contrast, UCP3L and UCP3S mRNAs were decreased by 38% (p < 0.0059) and 48% (p<0.0047), respectively, in 20% weight‐reduced patients with obesity at stable weight. In contrast, UCP2 mRNA levels were increased by 30% in skeletal muscle of 20% weight‐reduced subjects with obesity. In a different set of patients, mostly lean, UCP3L mRNA in skeletal muscle was decreased by 28% (p = 0.0425) after 10% weight reduction at stable weight. Expression of UCP2 mRNA in subcutaneous adipose tissue was similar in lean individuals and in individuals with obesity, and was increased by 58% during active weight loss.

Discussion: Stabilization at reduced body weight in humans is associated with a decrease in UCP3 mRNA in muscle. It is possible that reduced UCP3 expression could contribute to decreased energy expenditure in weight‐stable, weight‐reduced individuals.
Basal and Stimulated Plasma Leptin in Diabetic Subjects
Authors: Liu Jianmei , Askari Hasan , Dagogo‐Jack Samuel
Published: September 2012

LIU, JIANMEI, HASAN ASKARI, AND SAMUEL DAGOGO‐JACK. Basal and stimulated plasma leptin in diabetic subjects. Obes Res.

Objective: To determine whether leptin secretion is impaired in diabetes, we compared basal and stimulated plasma leptin levels in diabetic subjects and healthy controls.

Research Methods and Procedures: Blood samples for assay of leptin and other hormones were obtained at baseline in 54 diabetic patients and 65 controls, and 8 hours, 16 hours, and 40 hours following ingestion of dexamethasone (4 mg) in 6 healthy and 12 controls. C‐peptide status was defined as “negative” if ≤0.1 ng/mL or “positive” if ≥0.3 ng/mL, in fasting plasma.

Results: Basal plasma leptin levels were 19. 7±2. 2 ng/mL in nondiabetic subjects, 13. 4±1. 5 ng/ml in C‐peptide negative (n = 28) and 26. 1±23. 7 ng/mL in C‐peptide positive (n = 26, p = 0. 001) diabetic patients. Dexamethasone increased leptin levels of controls (n = 6) to 145±17% of baseline values at 8 hours (p = O. O3), 224±18% at 16 hours (p = 0. 01), and 134218% at 40 hours (p = 0. 05). The corresponding changes were 108±13%, 126±23%, and 98±16% in C‐peptide negative (n = 6), and 121±10%, 144±16% (p = 0. 03), and 147±23% (p = 0. 11) in C‐peptide positive (n = 6) diabetic patients, respectively. The peak stimulated leptin levels were lower in the diabetic patients, compared with controls. Plasma insulin increased (p = 0. 02) in controls, but not in the diabetic patients, following dexamethasone.

Discussion: Although diabetic patients have normal plasma leptin levels under basal conditions, their leptin responses to glucocorticoid are impaired, probably because of the concomitant insulin secretory defect. A subnormal leptin secretory response could worsen obesity and insulin resistance in diabetes.
Mistreatment Due to Weight: Prevalence and Sources of Perceived Mistreatment in Women and Men
Authors: Falkner Nicole H. , French Simone A. , Jeffery Robert W. , Neumark‐Sztainer Dianne , Sherwood Nancy E. , Morton Noelle
Published: September 2012

FALKNER, NICOLE H, SIMONE A. FRENCH, ROBERT W. JEFFERY, DIANNE NEUMARK‐SZTAINER, NANCY E. SHERWOOD, AND NOELLE MORTON. Mistreatment due to weight: prevalence and sources of perceived mistreatment in women and men. Obes Res.

Objective: Previous research has documented prejudicial attitudes and discrimination against overweight people. Yet the extent to which overweight people themselves perceive that they have been mistreated because of their weight has not been carefully studied. The purpose of this study was to examine the prevalence of perceived mistreatment due to weight and sources of perceived mistreatment.

Methods and Procedures: A non‐clinical sample of healthy adults (187 men and 800 women) enrolled in a weight gain prevention program comprised the study population. A self‐administered questionnaire was used to measure perceived mistreatment due to weight.

Results: Overall, 22% of women and 17% of men reported weight‐related mistreatment. The most commonly reported sources of mistreatment among women were strangers (12. 5%) and a spouse or loved one (11. 9%). Men were most likely to report mistreatment by a spouse or loved one (10. 2%) and friends (7. 5%). Somewhat surprisingly, sex differences in perceived weight‐related mistreatment were significant only for stranger as the source. Perceived weight‐related mistreatment was positively associated with body mass index (BMI) (r = 0. 39, p<0. 0001). Reported mistreatment was nearly ten times as pervalent among individuals in the highest quartile of the BMI distribution (42. 5%) than among those in the lowest BMI quartile (5. 7%), but was significantly greater than zero in all but the very lean.

Discussion: Perceived mistreatment due to weight is a common experience and is not restricted to the morbidly obese. Results are discussed in light of the sociocultural value for thinness.