bluuebunny/crossref_metadata_2025 huggingface dataset:
Weight‐Related Attitudes and Behaviors of Women Who Diet to Lose Weight: A Comparison of Black Dieters and White Dieters
Authors: Striegel‐Moore Ruth H. , Wilfley Denise E. , Caldwell Melissa B. , Needham Martha L. , Brownell Kelly D.
Published: September 2012

Obesity is a significant health problem among black women in the United States. Black women are two to three times more likely than white women to be obese. The present study sought to examine race differences in attitudes and beliefs about dieting, motivations underlying dieting efforts, and actual dieting strategies and behaviors. To achieve this aim, a subset of female survey respondents (n = 324) was drawn from a pool of more than 20,000 subscribers to Consumer Reports. All survey respondents had made at least one dieting effort within 3 years of the time of the study. For this study, we used all black female respondents (n = 162) and a matched sample (i.e., matched on age, educational attainment, and personal income) of white women (n = 162). Black women did weigh significantly more than Caucasian women, therefore, BMI was used as a covariate in all subsequent analyses.

Black and white women were significantly different in a number of domains. Compared to white women, black women experienced less social pressure about their weight, initiated dieting later in life, and were significantly less likely to diet at each developmental milestone. However, the two groups of women did not differ in reasons for undertaking their most recent dieting efforts, or in the types of weight loss strategies they had employed. Nor were there differences between the black and white women in methods for coping responses with dietary relapse or in rates of disordered eating. These findings are discussed in terms of their implications for both treatment and prevention of obesity in black women.
Body Position, Age and Mass Effect of Adiposity on Adipose Tissue Red Cell Flux in Morbid Obesity
Authors: Klassen Gerald A. , Janigan David , Paton Barry , Mathews John , Perey Bernard , Macdonald Allan S. , Barclay Katherine D.
Published: September 2012

Objective: To measure red cell flux of adipose tissue in morbidly obese patients' pannus in the upright and supine position to determine factors which would render the lower pannus susceptible to ischemic necrosis.

Design: A cohort study of morbidly obese subjects without ischemic necrosis.

Setting: University teaching hospital.

Patients: Twenty‐three consecutive morbidly obese patients referred for gastroplasty.

Measurements: Red cell flux, measured as RMS voltage by a laser Doppler velocimeter. An optical fiber with a tip diameter of 250μ was inserted into the upper and lower pannus and output recorded in the upright and supine positions. Other variables recorded were age, BMI, blood pressure and serum lipids.

Results: Adipose tissue red cell flux demonstrates considerable spatial and temporal heterogeneity from subject to subject and in various locations in the pannus. No differences in red cell flux were detected in response to change in position. However, regression analysis demonstrated that the gradient between the upper and lower abdomen in the supine position was increasingly positive with age and in the upright position it was increasingly positive with increasing weight or BMI.

Conclusions: These data suggest that red cell flux is heterogeneously distributed in the abdominal pannus and is not greatly influenced by body position. However, with increasing age and adiposity there is a gradient for decreased red cell flux to the lower portion of the pannus. This may be a factor in rendering this part of the pannus prone to ischemic fat necrosis.
Waist Circumference as the Best Predictor of Noninsulin Dependent Diabetes Mellitus (NIDDM) Compared to Body Mass Index, Waist/hip Ratio and Other Anthropometric Measurements in Mexican Americans—A 7‐Year Prospective Study
Authors: Wei Ming , Gaskill Sharon P. , Haffner Steven M. , Stern Michael P.
Published: September 2012

Although a number of obesity‐related variables are recognized risk factors for NIDDM, few studies have addressed which one is the best predictor. A cohort of 721 Mexican Americans aged 25–64 years who were free of NIDDM at baseline were followed for an average of 7.2 years; 105 new cases of NIDDM were diagnosed. Body weight, body mass index (BMI), waist and hip circumferences, waist/hip ratio (WHR), triceps and subscapular skinfolds were all positively predictive of NIDDM independent of age and sex. There were modest to strong correlations between these anthropometric variables, however, waist circumference was the strongest predictor of NIDDM. The predictive power of a single measurement of waist circumference was at least equal to that of WHR and BMI combined. The risk of NIDDM for those in the highest quartile of waist circumference was 11 times greater than for those in the lowest quartile (95% confidence interval: 4.2–28.8). The waist‐NIDDM relation was stronger in subjects with BMI ≤ 27 kg/m2 (OR: 6.0 for a 1 SD difference) than in subjects with BMI > 27 kg/m2 (OR: 1.7 for a 1 SD difference). In multivariate analysis, waist circumference was the only significant predictor of NIDDM in models that included other anthropometric variables either separately or simultaneously. WHR and BMI were independent predictors of NIDDM after adjustment for each other, however, their predictive abilities disappeared after adjustment for waist circumference. The data indicate that waist is the best obesity‐related predictor of NIDDM. This finding suggests that the distribution of body fat, especially abdominal localization, is a more important determinant than the total amount of body fat of the development of NIDDM in Mexican Americans.
Differential Responsiveness of Obese (fa/fa) and Lean (Fa/Fa) Zucker Rats to Cytokine‐Induced Anorexia
Authors: Plata‐Saláman Carlos R. , Vasselli Joseph R. , Sonti Gayatri
Published: September 2012

Pathophysiological and pharmacological concentrations of tumor necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β) in the cerebrospinal fluid (CSF) induce anorexia in normal rats. Obesity in humans and rodents is associated with increased TNF‐α messenger RNA and protein levels in various cell types. This suggests that obese individuals may have differential regulation of cytokine production and dissimilar responsiveness to cytokines. In the present study, we investigated the effects of the intracerebroventricular (ICV) microinfusion of TNF‐α (50, 100, and 500 ng/rat), IL‐1β (1.0, 4.0, and 8.0 ng), and TNF‐α (100 ng) plus IL‐1β (1.0 ng) on obese (fa/fa) and lean (Fa/Fa) Zucker rats. The results show that: TNF‐α and IL‐1β, and the concomitant administration of TNF‐a and IL‐ip decreased the short‐term (4 hours), nighttime (12 hours), and total daily food intakes in obese and lean rats; IL‐1β was more potent relative to TNF‐α; obese rats showed greater responsiveness to IL‐1β: 8.0 ng IL‐1β, for example, decreased the 12‐hour food intake by 52% in obese and 22% in lean rats. On the other hand, obese and lean rats did not exhibit a significantly different responsiveness to the anorexia induced by 50,100, or 500 ng TNF‐α at the 4‐hour period; and the concomitant ICV administration of TNF‐α and IL‐1β induced anorexia with additive (4‐hour period) or synergistic (12‐hour and 24‐hour periods) effects in obese rats. The effect of TNF‐α plus IL‐1β in lean rats was greater than additive for the 12‐hour and 24‐hour periods. The difference in suppression of total daily food intake by TNF‐α plus IL‐1β in obese (‐43%) versus lean (‐23%) rats was significantly different (p<0.01). The results show that obese (fa/fa) and lean (Fa/Fa) Zucker rats have differential responsiveness to the ICV microinfusion of two different classes of cytokines.
Low‐Fat Diets May Prevent Weight Gain in Sedentary Women: Prospective Observations From the Population Study of Women in Gothenburg, Sweden
Authors: Lissner Lauren , Heitmann Berit L. , Bengtsson Calle
Published: September 2012

The Population Study of Women in Gothenburg, Sweden is an ongoing prospective study of female residents who were recruited from the local registry in 1968–1969 when they were 38–60 years old. The data presented here were collected from 361 healthy women who underwent a baseline physical examination including a supplementary dietary history interview and returned for a second general health examination 6 years later. This report identifies a subgroup of 57 women who were sedentary during their leisure time and appear to have been particularly susceptible to gaining weight as a function of the fat content of their diets. Specifically, longitudinal analysis of body weights in the whole sample revealed a statistical interaction between leisure‐time physical activity and habitual dietary fat intake (energy‐%), as reported at the baseline examination, in the prediction of subsequent weight change. Further stratified analysis suggested that weight changes were significantly dependent on dietary fat intake among the sedentary women only. High energy intake also predicted weight gain in the sedentary group, although the predictive value for a high‐fat diet was of marginal significance after adjusting for total energy consumption. These results suggest that sedentary recreational activity plus a low‐fat diet may have a combined contribution to weight change that is not equivalent to the sum of the separate effects. Such a synergy between two modifiable lifestyle factors seems highly relevant for prevention of obesity.
Location and Effect of Obesity on Putative Anorectic Binding Sites in the Rat Brain
Authors: Dunn‐Meynell A.A. , Levin B.E.
Published: September 2012

Anorectic drugs such as mazindol bind to a class of low‐affinity, sodium‐sensitive sites in the brain which are affected by ambient glucose concentrations and a predisposition to develop diet‐induced obesity (DIO). This study used quantitative autoradiography of 10 nM 3H‐mazindol binding to identify the cellular location of these putative anorectic binding sites in the brain and to assess the way in which the development of DIO affected their binding. We previously showed that chow‐fed, obesity‐prone rats have widespread increases in brain 3H‐mazindol binding to these low‐affinity sites as compared with diet‐resistant (DR) rats. Here, low‐affinity 3H‐mazindol binding was assessed in the brains of eight rats which developed DIO vs. eight which were DR after three months on a high‐energy diet. DIO rats gained 89% more weight and had 117% higher plasma insulin levels but no difference in plasma glucose levels compared with DR rats. Along with these differences, low‐affinity 3H‐mazindol binding in DIO rats was identical to that in DR rats in all of the 23 brain areas assessed. This suggested that this binding was downregulated by the development of obesity in DIO rats. In other chow‐fed rats, stereotaxic injections of 5,7‐dihydroxytrypta‐mine and 6‐hydroxydopamine (60HDA) to ablate serotonin and catecholamine nerve terminals in the ventromedial nucleus of the hypothalamus (VMN) had no effect on 3H‐mazindol binding. However, ibotenic acid injected into the VMN, substantia nigra, pars reticulata, and pars compacta destroyed intrinsic neurons and/or their local processes and decreased low‐affinity 3H‐mazindol binding by 13%‐22%. Destruction of dopamine neurons in the substantia nigra, pars compacta, and noradrenergic neurons in the locus ceruleus with 60HDA also reduced 3H‐mazindol binding in those areas by 9% and 12%, respectively. This suggested that up to 22% of putative anorectic binding sites may be located on the cell bodies of dopamine, norepinephrine, and other neurons, but not on serotonin or catecholamine nerve terminals in the brain. Binding to these sites may be downregulated by the development of DIO, possibly as a result of the concomitant hyperinsulinemia.
Lifestyle Modification in the Pharmacologic Treatment of Obesity: A Pilot Investigation of a Potential Primary Care Approach
Authors: Wadden Thomas A. , Berkowitz Robert I. , Vogt Renee A. , Steen Suzanne N. , Stunkard Albert J. , Foster Gary D.
Published: September 2012

This study examined a new method of providing brief, individual lifestyle modification to obese individuals treated by pharmacotherapy. Twenty‐six women with a mean (±SD) age of 47.0 ± 7.2 years, weight of 97.6 ± 13.0 kg, and body mass index of 36.5 ± 5.0 kg/m2 were prescribed 60 mg/d of fenfluramine and 15 mg/d of phentermine for one year. In addition, half of the women were randomly assigned to traditional group behavior modification, conducted by a nutritionist, which included 32 75‐minute sessions during the year. The other half were provided lifestyle modification by a physician during 10 15–20 minute structured visits. All participants received identical treatment manuals and comparable assignments for behavior change. At the end of one year, patients in the physician group achieved the same highly successful weight losses as those treated by group behavior modification (13.9 ± 9.6 kg vs. 15.4 ± 7.9 kg, respectively). Treatment was associated with highly significant improvements in lipids and lipoproteins, as well as in mood and several measures of appetite. Weight loss the first four weeks, as well as patient completion of daily food records during the first 18 weeks, correlated positively with weight loss at weeks 18, 26, and 52. Results of this study await replication using larger samples but strongly suggest that effective lifestyle modification can be provided during brief, structured physician visits. The findings are discussed in terms of their implications for the treatment of obesity in primary care practice.
Aqueduct Occlusion Does Not Impair Feeding Induced by Either Third or Fourth Ventricle Galanin Injection
Authors: Koegler Frank H. , Ritter Sue
Published: September 2012

Exogenous galanin stimulates feeding when injected into forebrain and hindbrain sites, including the third and fourth ventricles (3V and 4V), amygdala, paraventricular nucleus of the hypothalamus (PVN), and nucleus of the solitary tract (NTS). Because the PVN and NTS border the ventricular space, it is possible that feeding stimulated by injection of galanin at these sites may be caused by the transport of galanin through the ventricular system to a remote site of action. The role of ventricular transport of galanin between the 3V and 4V in galanin‐induced feeding was examined in this study. Rats were implanted with two guide cannula assemblies: one dorsal to the mesencephalic aqueduct and the other in the 3V or 4V. Feeding in response to 3V or 4V galanin injection was first measured after sham‐occlusion of the aqueduct. Subsequently, flow of cerebrospinal fluid between the forebrain and hindbrain ventricles was acutely interrupted by injection of a silicone grease plug into the mesencephalic aqueduct just before assessment of the feeding response to 4V or 3V galanin injection. Aqueduct occlusion did not alter the feeding induced by either 3V or 4V galanin injection, indicating that galanin terminals in both the diencephalon and hindbrain are involved in control of food intake.
Cholecystokinin Decreases Food Intake in Rats1
Authors: Gibbs James , Young Robert C. , Smith Gerard P.
Published: September 2012

Partially purified cholecystokinin (CCK) was injected intraperitoneally into fasted rats prior to food presentation. The hormone produced a large doserelated suppression of intake of solid and liquid diets. Identical doses of the synthetic terminal octapeptide of cholecystokinin produced identical results. An effective dose of CCK did not suppress drinking after water deprivation. Treated animals did not appear ill and were not hyperthermic; neither CCK nor the octapeptide produced learning of a taste aversion in bait‐shyness tests. The effect of CCK is not a property of all gut hormones, since injections of secretin did not affect feeding. These studies raise the possibility that CCK plays an inhibitory role in the short‐term control of feeding behavior.
Cardiac Autonomic Nervous System Activity in Obese and Never‐Obese Young Men
Authors: Aronne Louis J. , Mackintosh Ronald , Rosenbaum Michael , Leibel Rudolph L. , Hirsch Jules
Published: September 2012

ARONNE, LOUIS J, RONALD MACKINTOSH, MICHAEL ROSENBAUM, RUDOLPH L LEIBEL, JULES HIRSCH. Cardiac autonomic nervous system activity in obese and never‐obese young men.

Autonomic nervous system (ANS) activity in age‐matched, weight‐stable, free‐living, ad libitumfed, obese (OB) and never‐obese (NO) young men (body mass index means [SD], 38.5 [3.9] and 22.0 [1.7], respectively) was evaluated by sequential blockade of cardiac autonomic innervation with weight‐adjusted doses of parasympathetic (atropine) and sympathetic (esmolol) blockers so as to produce maximal effects on heart rate. Change in heart period (interbeat interval) from baseline, induced by atropine, defined parasympathetic control (PC), and the subsequent change, after esmolol administration, defined sympathetic control (SC). The heart period, after PC and SC blockade, defined intrinsic heart period (I). In the OB group, baseline heart period and PC were lower, and SC and I were higher, than in the NO group. The results in the OB, relative to the NO subjects, are similar to those reported in a previous study of NO subjects who had undergone a 10% weight gain by overfeeding. These findings suggest that the ANS of individuals with obesity is chronically altered in a way that would tend to oppose their excessive adiposity, and that these autonomic changes are more likely to be responses to other forces that induce obesity, rather than being primary agents in the production of the disease.
Duration of Breastfeeding Associated With Obesity During Adolescence
Authors: Elliott Kristen G. , Kjolhede Chris L. , Gournis Effie , Rasmussen Kathleen M.
Published: September 2012

ELLIOTT, KRISTEN G, CHRIS L KJOLHEDE, EFFIE GOURNIS, KATHLEEN M RASMUSSEN. Duration of breastfeeding associated with obesity during adolescence.

The relationship between duration of breastfeeding and obesity (body mass index 85 percentile) at adolescence was investigated in a white, rural population (n=136) in which confounding by race was absent and confounding by socioeconomic status was expected to be minimal. Relevant data were abstracted from hospital charts. When examined independently, minimal (2 months) or no breastfeeding was positively associated with adolescent obesity (p<0. 03). This association was present in the lower but not the higher socioeconomic status group. However, when sex, birthweight, and socioeconomic status were included in a multiple regression model, duration of breastfeeding was no longer significantly associated with obesity during adolescence.
Long‐Term Drug Treatment of Obesity in a Private Practice Setting
Authors: Atkinson Richard L. , Blank Roy C. , Schumacher Donald , Dhurandhar Nikhil V. , Ritch Douglas L. ,   With clinical and technical assistance of Jon Levine, Chan Eric , Rieg Thomas S.
Published: September 2012

ATKINSON, RICHARD L, ROY C BLANK, DONALD SCHUMACHER, NIKHIL V DHURANDHAR, DOUGLAS L RITCH. Long‐term drug treatment of obesity in a private practice setting.

This study evaluated the long‐term efficacy and safety of the combination of phentermine and fenfluramine for the treatment of obesity in a private practice setting. A total of 1388 consecutive, qualified patients presenting to a private general internal medicine practice in Charlotte, NC, were enrolled with eligibility criteria including: age 18 years to 60 years, 20% over “desirable” bodyweight or body mass index <27, no serious medical or psychiatric disease, and no contraindications to drug therapy. Patients were instructed in diet, exercise, and behavior modification techniques and received phentermine (15 mg/day to 30 mg/day) and fenfluramine (20 mg/day to 60 mg/day) continuously for over 3 years. Average duration of treatment was 15. 9 months, and average weight loss at the last visit was 11. 6 kg, or 11. 7% of initial bodyweight. For patients completing 1 year of drug treatment, mean weight loss was 16. 5 kg, or 16% of initial weight. Weight loss persisted for 2 years, but partial regain was seen at 3 years. The dropout rates were 18% at 6 months, 39% at 1 year, 68% at 2 years, and 78% at 3 years. At 1 year, blood pressure of hypertensive patients fell from 151/95 mm Hg to 127/78 mm Hg, and serum cholesterol and triglycerides of hyperlipidemic patients fell by 0. 750 mmol/L (29 mg/dL) and 0. 937 mmol/L (83 mg/dL), respectively. Adverse events were modest. We conclude that, in a private practice setting, long‐term treatment of obesity with the combination of phentermine, fenfluramine, and a weight maintenance program is generally safe and effective. More research is needed to determine efficacy and safety for longer than 3 years.
Use of Very Low‐Calorie Diet in Preoperative Weight Loss: Efficacy and Safety
Authors: Pekkarinen Tuula , Mustaioki Pertti
Published: September 2012

PEKKARINEN, TUULA, PERTTI MUSTAJOKI. Use of very low‐calorie diet in preoperative weight loss: Efficacy and Safety.

We report the efficacy of a very low‐calorie diet (VLCD)‐based weight reduction program in patients with morbid obesity whose elective surgery had been postponed because of being overweight. The safety of weight loss on the immune system will also be evaluated. Thirty patients (mean age, 50 years; weight, 125 kg; BMI, 44 kg/m2) were treated. The program consisted of a 7‐week to 24‐week VLCD period, supported by individual sessions with a therapist, and of a refeeding period of 1 month before surgery. Two patients discontinued, and the mean weight loss of the remaining 28 patients was 19. 6 kg (15% of initial weight). In 23 patients, weight loss was 10% or more of the initial weight. After weight loss, 15 patients underwent surgery, 4 patients did not need an operation, and the remaining 9 patients were not operated on for various reasons. The numbers of circulating leukocytes, neutrophils, basophils, monocytes, CD3+, CD4+, CD8+, and natural killer cells did not change significantly by the ninth week on VLCD or by the end of the program. However, there was a significant (p<0. 05) decrease in the immunoglobulinM serum concentration during the program. In conclusion, a VLCD program is suitable for preoperative weight reduction in morbid obesity and seems not to compromise the immune system.
Relationship of Glycogen Synthase and Glycogen Phosphorylase to Protein Phosphatase 2C and cAMP‐Dependent Protein Kinase in Liver of Obese Rhesus Monkeys
Authors: Ortmeyer H. K.
Published: September 2012

ORTMEYER HK. Relationship of glycogen synthase and glycogen phosphorylase to protein phosphatase 2C and cAMP‐dependent protein kinase in liver of obese rhesus monkeys.

The regulation of glycogen synthase (GS) and glycogen phosphorylase (GP) activity by phosphorylation/ dephosphorylation has been proposed to be via changes in activities of several different protein (serine/ threonine) phosphatases and kinases, including protein phosphatase (PP) 1/2A, PP2C, and cAMP‐dependent protein kinase (PKA). In order to determine whether PP1/2A, PP2C, and/or PKA activities are related to GS and/or GP activities, these enzymes were measured in freeze‐clamped liver biopsies obtained under basal fasting conditions from 16 obese monkeys. Four monkeys were normoglycemic and normoinsulinemic, five were hyperinsulinemic, and seven had type 2 diabetes (NIDDM). Liver glycogen and glucose 6‐phosphate (G6P) contents were also determined. Basal enzyme activities and basal substrate concentrations were not significantly different between the three groups of obese monkeys; however, there were several significant linear relationships observed when the monkeys were treated as one group. Therefore, multiple regression was used to determine the correlation between key variables. GS fractional activity was correlated to GP fractional activity (p<0. 05) and to PP2C activity (p=0. 005) (adjusted R2,53%). GP independent activity was correlated to GS independent activity (p<0. 07) and to PKA fractional activity (p=0. 005) (adjusted R2,64%). PP2C activity was correlated to GS fractional activity (p<0. 0005) and to PP1/2A activity G7<0. 0001) (adjusted R2,83%). PKA fractional activity was correlated to GP total activity (p<0. 0005) and to age (p=0. 001) (adjusted R282%). G6P content was correlated to glycogen content (p<0. 05) and to PP2C activity (p=0. 0005) (adjusted R2,73%). In conclusion, PP2C and PKA are involved in the regulation of GS and GP activity in the basal state in liver of obese monkeys with a wide range of glucose tolerance.
A Role for Brown Adipose Tissue in Diet‐Induced Thermogenesis
Authors: Rothwell Nancy J. , Stock Michael J.
Published: September 2012

Measurement of energy balance during voluntary overeating in rats unequivocally establishes the quantitative importance of diet‐induced thermogenesis in energy balance. Like cold‐induced thermogenesis, this form of heat production involves changes in the activity of the sympathetic nervous system and brown adipose tissue which suggest that this tissue may determine metabolic efficiency and resistance to obesity.
Relationship of Anterior and Posterior Subcutaneous Abdominal Fat to Insulin Sensitivity in Nondiabetic Men
Authors: Misra Anoop , Garg Abhimanyu , Abate Nicola , Peshock Ronald M. , Stray‐Gundersen James , Grundy Scott M.
Published: September 2012

Recent studies from our group reveal that adipose tissue (AT) in the subcutaneous abdominal region is the most important determinant of peripheral and hepatic insulin sensitivity. Because of different anatomic and physiologic characteristics of anterior and posterior subcutaneous abdominal AT, we investigated the relationship of the masses of each compartment, as determined by magnetic resonance imaging, to insulin sensitivity (using euglycemic hyperinsulinemic glucose clamp technique), and other anthropometric variables. Thirty‐four healthy men with varying ranges of obesity were recruited for the study. The mass of posterior subcutaneous abdominal AT was ∼1.6 times more than that of the anterior compartment, and these masses accounted for 12.9% and 8.2% of the total body fat mass, respectively. All anthropometric variables, including body mass index (BMI), waist‐to‐hip circumference ratio (WHR), skinfold thicknesses, and intraperitoneal AT mass were more significantly related to the posterior than the anterior subcutaneous abdominal AT mass. Compared to the anterior compartment mass, the posterior compartment mass displayed stronger relationship with insulin‐mediated glucose disposal (Rd) (r=‐0.44, p=0.009, and r=‐0.76, p=0.0001, respectively) as well as with residual hepatic glucose output during the 40 mU.−2.min‐1 insulin infusion (r=0.39, p=0.02, and r=0.53, p=0.001, respectively). After adjusting for total body fat, the Rd values showed a significant partial correlation with the posterior subcutaneous abdominal AT mass (r=‐0.52, p=0.002). To conclude, posterior subcutaneous abdominal AT mass is a more important determinant of peripheral and hepatic insulin sensitivity than the anterior subcutaneous abdominal AT.
Relationships of Plasma Leptin Levels to Changes in Plasma Free Fatty Acids in Women Who Are Lean and Women Who Are Abdominally Obese
Authors: Hennes Magda M.I. , Dua Arnavaz , Maas Diana L. , Sonnenberg Gabriele E. , Krakower Glenn R. , Kissebah Ahmed H.
Published: September 2012

HENNES, MAGDA MI, ARNAVAZ DUA, DIANA L MAAS, GABRIELE E SONNENBERG, GLENN R KRAKOWER, AHMED H KISSEBAH. Relationships of plasma leptin levels to changes in plasma free fatty acids in women who are lean and women who are abdominally obese.

Regulation of leptin production by the hormonal and metabolic milieu is poorly understood. Because abdominal obesity is commonly associated with elevated plasma free fatty acid (FFA) flux, we examined the effects of augmenting FFA on plasma leptin levels in women who were lean and of suppressing FFA in women with abdominal obesity. In study 1, nine subjects who were lean, after a 12‐hour overnight fast, received either intravenous saline or Intralipid plus heparin to increase the plasma FFA concentration to approximately 1000 μmol/ L. After 3 hours of additional fasting, subjects underwent 3‐hour hyperglycemic clamps. In study 2, seven subjects with abdominal obesity were evaluated by a similar protocol, but lipolysis and plasma FFA flux were instead maximally suppressed by acipimox. In the individuals who were lean, leptin levels were unchanged during clamping. Increasing plasma FFA reduced plasma leptin from 7.66 ± 0.66 to 7.05 ±0 0.66 (p=0.03), but 3 hours of hyperglycemia plus hyperinsulinemia had no additional effect on leptin levels (7.15 ± 0.71). Basal leptin levels, 4‐fold higher in the subjects with obesity, were reduced from 34.6 ± 2.4 μg/L to 32.3 ± 1.1 μg/L (p=0.004) during the clamp period. When plasma FFA flux was suppressed, however, plasma leptin levels after clamped hyperglycemia/hyperinsulinemia were increased to 38.9 ± 1.2 μg/L (p=0.014 vs. time 0 and 0.001 vs. saline protocol). Changes in leptin concentrations are not correlated with changes in FFA. These results suggest that plasma FFA concentration does not regulate plasma leptin levels in basal, extended fasting, or hyperglycemic/hyperinsulinemic states.
Differential Short‐Term Distribution of Estrone and Oleoyl‐Estrone Administered in Liposomes to Lean and Obese Zucker Rats
Authors: Balada F. , Sanchis D. , Grasa M.M. , Virgili J. , Estruch J. , Fernændez‐López J.A. , Remesar X. , Alemany M.
Published: September 2012

Thirteen‐week‐old female Zucker lean (Fa/Fa) and obese (fa/fa) rats were injected through a cannula inserted in the left jugular vein with 1 mL/kg of 3H‐labeled oleoyl‐estrone in liposomes (Merlin‐2) (i.e., 670 fmol, 84 kBq). The rats were killed 10 minutes later and dissected. The presence of intact or hydrolyzed oleoyl‐estrone was later determined in all samples. The pattern of distribution of estrone was quite different from that of oleoyl‐estrone both in rats that were lean and in those that were obese. Estrone was better retained by white adipose tissue than oleoyl‐estrone. Liver, spleen, and lungs accumulated more oleoyl‐estrone and split part of it, from 4.7% (lung, obese) to 27% (liver, lean). The overall high retention of estrone by the rat tissues results in its very low circulating levels. The fast splitting of liposome‐carried oleoyl‐estrone by most tissues (up to more than 67% by intestine and skin of lean rats) may help explain the rise in blood free estrone. The differences between lean and obese Zucker rats are mainly quantitative in the case of estrone, the main differences being found in blood and adipose tissues. However, when we compare the data for oleoyl‐estrone, the differences cannot be dismissed simply as due to differences in body size or the extent of fat deposits. A large portion of the label remained in the blood of the rats that were obese but not in those that were lean, the tissues of which took up more label. Brown adipose tissue shows a fair affinity for oleoyl‐estrone in the rats that were lean but practically does not retain label in the rats that were obese, suggesting that oleoyl‐estrone may have a direct effect on brown adipose tissue. The decreased uptake of oleoyl‐estrone in rats that were obese shows that the mechanism regulating the turnover or disposal of this signal is altered in this type of genetic obesity.
Realistic Weight Perception and Body Size Assessment in a Racially Diverse Community Sample of Dieters
Authors: Cachelin Fary M. , Striegel‐Moore Ruth H. , Elder Katherine A.
Published: September 2012

Recently, a shift in obesity treatment away from emphasizing ideal weight loss goals to establishing realistic weight loss goals has been proposed; yet, what constitutes “realistic” weight loss for different populations is not clear. This study examined notions of realistic shape and weight as well as body size assessment in a large community‐based sample of African‐American, Asian, Hispanic, and white men and women. Participants were 1893 survey respondents who were all dieters and primarily overweight. Groups were compared on various variables of body image assessment using silhouette ratings. No significant race differences were found in silhouette ratings, nor in perceptions of realistic shape or reasonable weight loss. Realistic shape and weight ratings by both women and men were smaller than current shape and weight but larger than ideal shape and weight ratings. Compared with male dieters, female dieters considered greater weight loss to be realistic. Implications of the findings for the treatment of obesity are discussed.
The Human Obesity Gene Map: The 1997 Update
Authors: Chagnon Yvon C. , Pérusse Louis , Bouchard Claude
Published: September 2012

An update of the human obesity gene map incorporating published results up to October 1997 is presented. Evidence from Mendelian disorders exhibiting obesity as a clinical feature; single‐gene mutation rodent models; quantitative trait loci uncovered in human genome‐wide scans and in crossbreeding experiments with mouse, rat, and pig models; association and case‐control studies with candidate genes; and linkage studies with genes and other markers is reviewed. All chromosomal locations of the animal loci are converted into human genome locations based on syntenic relationships between the genomes. A complete listing of all of these loci reveals that all but chromosome Y of the 24 human chromosomes are represented. Some chromosomes show at least three putative loci related to obesity on both arms (1, 2, 6, 8, 11, and 20) and several on one chromosome arm only (3p, 4q, 5q, 7q, 12q, 13q, 15q, 15p, 22q, and Xq). Studies reporting negative association and linkage results are also listed, with the exception of the unlinked markers from genome‐wide scans.
Leptin Receptor Gene in a Large Cohort of Massively Obese Subjects: No Indication of the fa/fa Rat Mutation. Detection of an Intronic Variant with No Association with Obesity
Authors: Rolland Violaine , Clement Karine , Dugail Isabelle , Guy‐Grand Bernard , Basdevant Arnaud , Froeuel Philippe , Lavau Marcelle
Published: September 2012

The massive obesity caused in rodents by the disruption of the leptin‐receptor signal through genetic defects at the level of either leptin (OB) or leptin receptor (OB‐R) has raised the question of the relevance of these genes to morbid obesity in humans. In this study, we screened a large population of massively obese subjects for the presence of a leptin receptor mutation homologous to that of fa/fa rats, a single base substitution changing glutamine 269, a highly conserved glutamine found at position 270 in the human sequence. After polymerase chain reaction (PCR) amplification of a DNA region encompassing the end of exon 5, intron 5, and the beginning of exon 6, we performed restriction fragment length polymorphism analysis. Within the limitations of this approach where only mutations introducing restriction sites (5 of 8 possibilities) could be assessed, no evidence of mutation at the codon gin 270 was found in 343 massively obese subjects. However, a new OB‐R gene variant in intron 5 was revealed by Maell digestion of the PCR products. MaelVhOB‐R genotyping revealed no difference in the distribution of the genotypes between obese subjects and a group of 79 unrelated non‐obese control subjects. In addition, no significant association between various obesity‐related metabolic phenotypes and the presence of MaeII/hOB‐R alleles was found. Thus, our results did not support a significant role for the Maell/hOB‐R gene variant in the development of the obese phenotype in the population we studied.
Circulating Insulin Concentrations, Smoking, and Alcohol Intake Are Important Independent Predictors of Leptin in Young Healthy Men
Authors: Mantzoros Christos S. , Liolios Antonios D. , Tritos Nicholas A. , Kaklamani Virginia G. , Doulgerakis Dimitrios E. , Griveas Ioannis , Moses Alan C. , Flier Jeffrey S.
Published: September 2012

Objective: Leptin, an adipocyte‐secreted hormone, has been shown to signal the status of energy stores to the brain, regulate energy homeostasis, and mediate the neuroendocrine response to food deprivation. Obesity is associated with increased leptin levels, and several hormones, including insulin and glucocorticoids, have been associated with leptin levels and expression in rodents. Although obesity has been strongly associated with increased leptin in humans, a significant percentage of leptin's variability remains unexplained. The role of endogenous hormones, demographic factors, or certain life‐style factors in explaining the residual variability of leptin levels has not yet been clarified. We performed this cross‐sectional study to document the relative importance of obesity, lifestyle factor, and endogenous hormones in determining serum leptin levels.

Research Methods and Procedures: We measured serum concentrations of insulin, Cortisol, testosterone, growth hormone, and dehydroepiandrosterone sulfate; ascertained anthropometric, demographic, and lifestyle characteristics; and studied these variables in relationship to serum leptin concentrations in a sample of young healthy men.

Results: Obesity and alcohol intake were independently and positively associated with circulating leptin concentrations.

Additionally, cigarette smoking was negatively and independently associated with leptin concentrations. Finally, serum insulin concentration was an independent hormonal determinant of circulating leptin concentrations, whereas serum testosterone was negatively associated with leptin only by bivariate analysis.

Discussion: We conclude that, in addition to obesity, cigarette smoking, alcohol intake, and serum insulin levels are associated with leptin levels in a population of healthy young men.
Further Support for Consistent Self‐Monitoring as a Vital Component of Successful Weight Control
Authors: Boutelle Kerri N. , Kirschenbaum Daniel S.
Published: September 2012

Objective: This study attempted to replicate that of Baker and Kirschenbaum by providing a descriptive analysis of the relationship between self‐monitoring and weight control.

Procedures: Fifty‐nine women and men in long‐term cognitive‐behavioral treatment for obesity participated over an 8‐week period. Percentages of participants who self‐monitored consistently and the relationship between the variability in self‐monitoring and weight change were examined.

Results: As in the previous study, a substantial minority of the participants in this research (26.3%) self‐monitored all foods eaten on less than half of the days evaluated. The assertion of Baker and Kirschenbaum that self‐monitoring is most appropriately viewed as both a state and a trait was supported by finding that the most consistent self‐monitors lost more weight than the least consistent self‐monitors; however, regardless of overall self‐monitoring consistency, participants lost much more weight during their two most consistent weeks compared with their two least consistent weeks. Again, as in the previous study, only the more consistent quartile of self‐monitors lost a substantial amount during the course of this study.

Discussion: The results of both studies taken together suggests that a reasonable target for consistency for self‐monitoring within the context of a professional cognitive‐behavioral treatment program may be self‐monitoring all foods eaten on at least 75% of the days. If participants generally self‐monitor on less than half of the days during participation in such programs, they may be very unlikely to succeed at weight loss both during the program and afterward.
Effects of the Menopause Transition on Body Fatness and Body Fat Distribution
Authors: Tchernof André , Poehlman Eric T.
Published: September 2012

Objective: The menopause transition increases cardiovascular and metabolic disease risk, partly because of the adverse effects of estrogen deficiency on the plasma lipid‐lipoprotein profile and cardiovascular function. This increased cardiovascular and metabolic disease risk may also be partially mediated by increased body fat, increased intraabdominal adipose tissue accumulation, or both. The objective of this mini‐review is to summarize studies that have investigated the relationships among the menopause transition, body fatness, and body fat distribution.

Research Methods and Procedures: A review of cross‐sectional and longitudinal studies on menopause that examined body fatness and body fat distribution.

Results: Cross‐sectional reports show that the menopause transition is related to modest increases in body mass index or total fatness, although not all studies found significant effects. Increased central adiposity appears to be related to menopause, independent of advancing age, but these results are methodology dependent. An independent effect of menopause on central body fatness was noted by the use of techniques such as DEXA or computed tomography, whereas studies using circumference measures showed discrepant results. Longitudinal studies showed that the menopause transition accelerated the increase in central adiposity, although no studies quantified changes in intra‐abdominal fat by imaging techniques.

Discussion: Thus, additional longitudinal studies using more accurate measures of adiposity are needed to critically examine the effects of the menopause transition on total and central body fatness. Collectively, previous studies suggest that menopause is related to modest increase in total fatness and accelerated accumulation of central body fat that exceeds changes normally attributed to the aging process. These changes may increase the risk for cardiovascular and metabolic disease in aging women.
Do Leptin Levels Predict Weight Gain?—A 5‐Year Follow‐Up Study in Mauritius
Authors: Hodge Allison M. , de Courten Maximilian P. , Dowse Gary K. , Zimmet Paul Z. , Collier Greg R. , Gareeboo Hassam , Chitson Pierrot , Fareed Djamil , Hemraj Farojdeo , Alberti K. George M.M. , Tuomilehto Jaakko
Published: September 2012

Objective: To investigate whether relative baseline leptin levels predict long‐term changes in adiposity and/or its distribution.

Research Methods and Procedures: In a longitudinal study of 2888 nondiabetic Mauritians aged 25 years to 74 years who participated in population‐based surveys in 1987 and 1992, changes in body mass index (BMI), waist/hip ratio (WHR), and waist circumference were compared between “hyperleptinemic,” “normoleptinemic,” and “hypoleptinemic” groups. “Relative leptin levels” were calculated as standardized residuals from the regression of log10 leptin on baseline BMI to provide a leptin measure independent of BMI. Analyses were performed within each sex. A linear regression model was used to assess the effect of standardized residuals on changes in BMI, WHR, and waist circumference, independent of baseline BMI, age, fasting insulin, and ethnicity.

Results: After adjusting for age and baseline BMI by analysis of covariance, there was no difference in changes in BMI, WHR, or waist circumference between men with low, normal, or high relative leptin levels. Among women, there was a significant difference in ΔWHR across leptin groups, such that the largest increase occurred in the “normal” leptin group. For both men and women, the linear regression models explained −10% of variation in dependent variables, and the only significant independent variables were age, BMI, and being of Chinese origin, compared with Indian origin.

Discussion: These findings do not support a role for leptin concentration in predicting weight gain or changes in fat distribution in adults over a 5‐year period.
Psychiatric III‐Health of Women and Its Relationship to Obesity and Body Fat Distribution
Authors: Rosmond Roland , Björntorp Per
Published: September 2012

Objective: Abdominal obesity is associated with serious, prevalent diseases. Previously, psychiatric symptoms and ill‐health has been found in this condition in men. The results of a similar study in women is reported herein.

Research Methods and Procedures: A cohort of 1464 women, aged 40 years and recruited by systematic sampling, was examined (77.7% participation rate). Items regarding use of anxiolytics, hypnotics, and antidepressive drugs were registered, as well as symptoms of dyspepsia, sleeping disturbances, melancholy, and degree of life satisfaction. Smoking and alcohol consumption, as well as self‐measured weight, height, waist, and hip circumferences, were reported, from which body mass index [BMI; weight (kg)/height2 (m2), kg/m2] and the waist/hip circumference ratio (WHR) were calculated.

Results: In bivariate analyses, BMI was associated with use of anxiolytics, antidepressive drugs, various sleeping disturbances, and a low degree of life satisfaction. After controlling for “the WHR, alcohol, and tobacco use in multivariate analysis, the associations between BMI and use of anxiolytics and sleeping disturbances remained significant. The WHR correlated with dyspepsia, sleeping problems, and use of antidepressive drugs. After adjustments for BMI, smoking, and alcohol, the relationship to dyspepsia and antidepressants remained significant.

Discussion: The results suggest that elevated BMI (obesity) and elevated WHR (central fat distribution) are associated in different ways with symptoms of psychiatric ill‐health in women. Obesity alone shows no such relationships to psy chiatric ill‐health in men, whereas central fat distribution shows independent associations to all of the measured variables studied in this report in women, suggesting gender differences in these associations.
Miglitol (BAY m 1099) Treatment of Diabetic Hypothalamic‐Dietary Obese Rats Improves Islet Response to Glucose
Authors: Axen Kathleen V. , Li Xue , Sclafani Anthony
Published: September 2012

AXEN, KATHLEEN V., XUE LI, AND ANTHONY SCLAFANI. Miglitol (BAY m 1099) treatment of diabetic hypothalamic‐dietary obese rats improves islet response to glucose. Obes Res. 1999;7:83–89.

Objective: The well‐absorbed α‐glucosidase inhibitor, miglitol (BAY m 1099), was included in the diets of hypothalamic‐dietary obese diabetic rats to investigate its ability to improve glycemia and thereby reverse glucotoxic effects on islet secretory response.

Research Methods and Procedures: Female rats received bilateral electrolytic lesions of the ventromedial hypothalamus and were fed high‐fat, sucrosesupplemented diets until hyperinsulinemia and hyperglycemia were observed after 3 hours of food deprivation (nonfed). Diabetic animals were assigned to miglitol‐treated (40 mg/17 g of diet) or untreated groups for 3 weeks; pancreatic islets were isolated for incubation experiments.

Results: No differences in food intake, body weights, or nonfed plasma glucose or insulin levels were seen between treated and untreated diabetic rats. Islets isolated from untreated diabetic rats showed elevated basal insulin release and no insulin secretory response to an elevation in glucose concentration. In contrast, islets obtained from miglitol‐treated rats showed more normal basal release and a significant insulin secretory response to glucose. Incubation of islets, obtained from normal control rats or untreated diabetic rats, in media containing miglitol at levels estimated to exist in plasma of treated rats had no effect on islet insulin secretory responses to glucose.

Discussion: Islet secretory response was improved despite continued hyperglycemia and severe insulin resistance. Miglitol treatment may improve islet sensitivity to glucose either through effects on islet metabolism requiring prolonged exposure or by improvement in postmeal glycemia, despite persistent hyperglycemia.