bluuebunny/crossref_metadata_2025 huggingface dataset:
BMI, Obesity, and Sickness Absence in the Whitehall II Study
Authors: Ferrie Jane E. , Head Jenny , Shipley Martin J. , Vahtera Jussi , Marmot Michael G. , Kivimäki Mika
Published: July 2008

Objective: To study BMI and change in BMI from age 25 as predictors of sickness absence.

Research Methods and Procedures: Data were collected from 2564 women and 5853 men, who were British civil servants (35 to 55 years) on entry to the Whitehall II study (Phase 1, 1985 to 1988). Employer's records provided annual medically certified (long, >7 days) and self‐certified (short, 1 to 7 days) spells of sickness absence. BMI at age 25 and Phase 1 were examined in relation to absences from Phase 1 to the end of 1998 (mean follow‐up, 7.0 years).

Results: After adjustment for employment grade, health‐related behaviors, and health status, overweight (BMI = 25.0 to 29.9 kg/m2) and obesity (BMI > 30.0 kg/m2) at Phase 1 were significant predictors of short and long absences in both sexes; rate ratios (95% confidence intervals) ranged from 1.13 (1.05 to 1.21) to 1.51 (1.30 to 1.76) compared with a BMI of 21.0 to 22.9 kg/m2. Additionally, a BMI of 23.0 to 24.9 kg/m2 at Phase 1 predicted long absences in women, and underweight (BMI < 21.0 kg/m2) predicted short absences in men. Obesity at age 25 predicted long absences, and obesity at Phase 1 predicted short and long absences in both sexes. Chronic obesity was a particularly strong predictor of long absences in men, with a rate ratio of 2.61 (1.88 to 3.63).

Discussion: Findings from this well‐characterized cohort suggest that the obesity epidemic in industrialized countries may result in significant increases in sickness absence. Further research is needed to determine the underlying mechanisms. Policy to reduce sickness absence needs to tackle the problem of excess weight in the working population.
Birth Weight Is Inversely Associated With Central Adipose Tissue in Healthy Children and Adolescents
Authors: Dolan Meredith S. , Sorkin John D. , Hoffman Daniel J.
Published: July 2008

Objective: Previous studies have explored the association between birth weight and excess childhood body fat, but few have used precise measures of body composition, leading to equivocal and sometimes contradictory results.

Research Methods and Procedures: Subjects included 101 children who underwent DXA measurements between 1995 and 2000. Birth weight and gestational age were assessed using maternal recall. Multiple linear regression analysis was used to determine the relationship between birth weight and the following four outcome variables: total fat mass (FM), truncal fat mass (TrFM), percentage body fat (%BF), and TrFM adjusted for FM (TrFMadj), controlling for current weight and Tanner stage.

Results: The mean age of the children studied was 12.9 ± 2.4 years, and the mean birth weight reported by subjects’ mothers was 3.3 ± 0.5 kg. The FM and TrFM were 12.8 ± 8.7 kg and 5.1 ± 4.1 kg, respectively, and the mean %BF was 22.9 ± 10.3%. Birth weight was a significant predictor of FM (p = 0.02) and %BF (p = 0.038). However, birth weight adjusted for gestational age (BWTadj) was a significant (p = 0.03) negative predictor of TrFMadj, independently of race, sex, Tanner stage, and current weight.

Discussion: These results provide evidence that, even in childhood and adolescence, a higher birth weight is associated with higher FM and %BF, while a low birth weight is associated with TrFM, adjusted for FM.
Birth Weight Correlates Differently with Cardiovascular Risk Factors in Youth
Authors: Wei Jung‐Nan , Li Hung‐Yuan , Sung Fung‐Chang , Lin Chau‐Ching , Chiang Chuan‐Chi , Li Chung‐Yi , Chuang Lee‐Ming
Published: July 2008

Objective: Childhood obesity has become prevalent, resulting in a greater risk of hypertension, diabetes, and dyslipidemia. However, the relationship between these comorbid conditions and birth weight remains uncertain. We conducted this study to evaluate the relationship between birth weight and cardiovascular risk factors in children and adolescents.

Research Methods and Procedures: In a nationwide survey conducted between 1992 and 2000, all schoolchildren 6 to 18 years old with glucosuria, proteinuria, or microscopic hematuria in repeated urine samples were included and received a physical examination and blood test. Those with gestational age <37 weeks were excluded. We enrolled 81,538 children (51,111 girls and 30,427 boys) and obtained their birth weights from the Taiwan Birth Registry. Obesity and hypertension were defined by age‐ and sex‐specific cut‐offs. Diabetes was diagnosed if the fasting glucose was >7 mM.

Results: The risk of obesity was higher for those with birth weights ≥4000 grams [odds ratio (OR), 1.65] and 3543 to 3999 grams (OR, 1.28) and lower for those with birth weights 2601 to 2999 grams (OR, 0.90), using 3000 to 3542 grams as the reference group. An increased risk of diabetes was associated with both higher and lower birth weights, indicating a U‐shaped relationship (OR, <2600 grams, 1.607; 2601 to 2999 grams, 1.119; 3543 to 3999 grams, 1.112; ≥4000 grams, 1.661). In the 10‐ to 12‐year‐old age group, the risk of hypertension was higher in those with birth weights <2600 grams (OR, 1.20).

Discussion: Low birth weight was associated with childhood diabetes. High birth weight was correlated with childhood obesity and diabetes. Our data indicate different relationships between birth weight and the development of obesity, hypertension, and diabetes in childhood.
Low Serum Leptin Predicts Mortality in Patients with Chronic Kidney Disease Stage 5
Authors: Scholze Alexandra , Rattensperger Dirk , Zidek Walter , Tepel Martin
Published: July 2008

Objective: Leptin, secreted from adipose tissue, regulates food intake, energy expenditure, and immune function. It is unknown whether leptin predicts mortality in patients with chronic kidney disease stage 5 on hemodialysis therapy.

Research Methods and Procedures: We performed a prospective cohort study of 71 patients with chronic kidney disease stage 5 in an outpatient hemodialysis center. Subjects were recruited in June 1998 and followed for 83 months. Survival was compared by the Kaplan‐Meier method.

Results: After 83 months of follow‐up, 48 patients (68%) had died. Serum leptin concentrations at study entry were lower among all deceased patients compared with those patients who survived (5.2 ± 9.0 μg/L; n = 48; vs. 7.7 ± 7.8 μg/L; n = 23; p = 0.005). Baseline serum leptin concentrations were significantly lower in patients who died from cardiovascular diseases (4.7 ± 9.4 μg/L, n = 32) or infections (4.0 ± 2.7 μg/L; n = 10; each p < 0.05), but not cancer (9.4 ± 7.9 μg/L; n = 6), than in survivors (7.7 ± 7.8 μg/L; n = 23; p = 0.003). The relative risk for mortality in patients with serum leptin concentrations below the median (<2.6 μg/L) compared with patients above the median was 1.96 (95% confidence interval, 1.01 to 3.79; p = 0.04). Survival was shorter in patients with leptin concentrations below the median compared with those whose leptin concentrations were above the median (all‐cause mortality, χ2 = 5.05; p = 0.02).

Discussion: Low serum leptin concentration is an independent predictor of mortality in patients with chronic kidney disease stage 5 on hemodialysis therapy.
Larger Anti‐adipogenic Effect of Angiotensin II on Omental Preadipose Cells of Obese Humans
Authors: Brücher Rodrigo , Cifuentes Mariana , Acuña María José , Albala Cecilia , Rojas Cecilia V.
Published: July 2008

Objective: The ability to form new adipose cells is important to adipose tissue physiology; however, the mechanisms controlling the recruitment of adipocyte progenitors are poorly understood. A role for locally generated angiotensin II in this process is currently proposed. Given that visceral adipose tissue reportedly expresses higher levels of angiotensinogen compared with other depots and the strong association of augmented visceral fat mass with the adverse consequences of obesity, we studied the role of angiotensin II in regulating adipogenic differentiation in omental fat of obese and non‐obese humans.

Research Methods and Procedures: The angiotensin II effect on adipose cell formation was evaluated in human omental adipocyte progenitor cells that were stimulated to adipogenic differentiation in vitro. The adipogenic response was measured by the activity of the differentiation marker glycerol‐3‐phosphate dehydrogenase.

Results: Angiotensin II reduced the adipogenic response of adipocyte progenitor cells, and the extent of the decrease correlated directly with the subjects’ BMI (p = 0.01, R2 = 0.30). A 56.3 ± 3.4% and 44.5 ± 2.7% reduction of adipogenesis was found in obese and non‐obese donors’ cells, respectively (p < 0.01). The effect of angiotensin II was reversed by type 1 angiotensin receptor antagonist losartan.

Discussion: A greater anti‐adipogenic response to angiotensin II in omental adipose progenitor cells from obese subjects opens a venue to understand the deregulation of visceral fat tissue cellularity that has been associated with severe functional abnormalities of the obese condition.
New Scanning Electron Microscopic Method for Determination of Adipocyte Size in Humans and Mice
Authors: Guo Wen , Bigornia Sherman , Leizerman Ilit , Xie Weisheng , McDonnell Marie , Clemente Kara , Pirtskhalava Tamara , Kirkland James L. , Gokce Noyan , Corkey Barbara E. , Sullivan Lisa M. , Apovian Caroline M.
Published: July 2008

Objective: To evaluate a new scanning electronic microscopic (EM) method for assessing fat cell sizes and compare fat cell size distribution in human adipose tissue from different fat depots before and after weight loss.

Research Methods and Procedures: Identical human fat tissue biopsies were separated into two fractions: one used to prepare a fat cell suspension by collagenase digestion followed by photomicrography (collagenase method) and the other fixed in formalin for EM analysis. The EM method was evaluated further by determining fat cell sizes from lean and ob/ob mice. Finally, the EM method was used to assess fat cell sizes in biopsies of different human depots from before and after weight loss.

Results: Fat cell size distributions measured by the two methods were not identical, but differences were generally small. The EM method reproduced the well‐documented fat cell size difference between lean and ob/ob mice. Large variation was detected in fat cell distributions among three depots in humans. Weight loss reduced fat cell sizes in subjects with large baseline fat cells but had no effect in subjects with small baseline fat cell sizes.

Discussion: Our results suggest that the EM method may be a useful alternative for fat cell size analysis of clinical samples.
Liraglutide, a Once‐daily Human Glucagon‐like Peptide‐1 Analog, Minimizes Food Intake in Severely Obese Minipigs
Authors: Raun Kirsten , von Voss Pia , Knudsen Lotte Bjerre
Published: July 2008

Objectives: To evaluate the efficacy of liraglutide, a new, stable, once‐daily human analog of glucagon‐like peptide‐1, in a new animal model of obesity.

Research Methods and Procedures: Liraglutide was administered subcutaneously once daily (7 μg/kg for 7 weeks) to six female obese Göttingen minipigs. Food intake and feeding patterns were monitored using a novel automated feeding system that allowed continuous recording of food intake.

Results: Food intake was strongly suppressed. A steady‐state level of reduced food intake was achieved within 3 weeks and was maintained for the remaining 4 weeks of the treatment period. During the 4‐week steady‐state period with liraglutide treatment, daily food intake was 7.3 ± 0.3 megajoule (MJ) compared with 18.4 ± 0.6 MJ in the pre‐treatment period and 19.2 ± 0.5 MJ in the post‐treatment period (p < 0.001). The food intake in the treatment period was equivalent to the amount of food that would have been offered to normal‐weight pigs for maintenance. Body weight decreased 4.3 ± 1.2 kg (4% to 5%) during the 7 weeks of treatment and increased 7.0 ± 1.0 kg during the 7 weeks of post‐treatment (p < 0.01). Appetite suppression was quickly reversed within 4 days after termination of liraglutide administration.

Discussion: Overall, liraglutide was well tolerated and had a profound and persistent anorectic effect that resulted in weight loss. These results, in conjunction with the previously established glucose‐lowering efficacy of liraglutide, suggest that the anorectic actions of liraglutide will be very important in clinical trials of both obese patients with type 2 diabetes and obese non‐diabetic patients.
Weekend and Weekday Patterns of Physical Activity in Overweight and Normal‐weight Adolescent Girls
Authors: Treuth Margarita S. , Catellier Diane J. , Schmitz Kathryn H. , Pate Russell R. , Elder John P. , McMurray Robert G. , Blew Robert M. , Yang Song , Webber Larry
Published: July 2008

Objective: To describe the patterns (specifically comparing weekdays and weekends classified by intensities) of physical activity (PA) measured by accelerometry in adolescent girls.

Research Methods and Procedures: Healthy sixth grade girls (n = 1603), 11 to 12 years old, were randomly recruited from 36 schools participating in the Trial of Activity in Adolescent Girls. Age, ethnicity, socioeconomic status, weight, and height were taken. PA patterns were measured for 6 days using accelerometry.

Results: Adolescent girls spend most of their time in sedentary (52% to 57% of the day) and light activity (40% to 45% of the day) on weekdays and weekends. In all girls, total PA comprised 44.5% of the day (41.7% light, 2.2% moderate, and 0.7% vigorous) with sedentary activity comprising 55.4%. Moderate‐to‐vigorous PA (MVPA) was higher (p < 0.001) on weekdays than weekends in all girls, but MVPA was lower in at‐risk of overweight + overweight girls (p < 0.001) on both weekdays and weekends compared with normal‐weight girls.

Discussion: Adolescent girls are more active at moderate and vigorous intensities on weekdays than on weekends, and at‐risk of overweight and those overweight spend less time engaging in MVPA than normal‐weight girls.
BMI May Overestimate the Prevalence of Obesity Among Women of Lower Socioeconomic Status
Authors: Kaluski Dorit Nitzan , Keinan‐Boker Lital , Stern Felicia , Green Manfred S. , Leventhal Alex , Goldsmith Rebecca , Chinich Ayelet , Berry Elliot M.
Published: July 2008

Objective: Our objective was to examine gender differences in height and weight associated with socioeconomic status (SES) and the consequent effect on body mass index in a multiethnic society.

Research Methods and Procedures: A cross‐sectional study, the First Israeli National Health and Nutrition Survey, was performed on a representative population sample of 3246 adults 25 to 64 years of age, between the years 1999 to 2001. Height and weight were measured, and BMI and other weight‐height indices were calculated. SES was assessed by income and education.

Results: Age‐adjusted height was significantly lower at lower levels of SES among both women and men (p < 0.001). As opposed to men, women of lower SES were heavier than those of higher SES, and the mean age‐adjusted weight was 4.6 kg higher among those of lower SES (p < 0.001). Thus, using the standard index of BMI, the prevalence of obesity was significantly higher among shorter women.

Discussion: In this group of Israeli adults, the unfavorable effect of low SES on BMI was evident among women, partly due to their decreased height combined with increased weight common in this socioeconomic sector. Since BMI is only partly independent of height, it may overestimate the prevalence of obesity among women of lower SES. Alternative measures for classifying obesity in the lower SES groups that put less emphasis on height may be considered and studied.
Obesity Profiles with Knee Osteoarthritis: Correlation with Pain, Disability, Disease Progression
Authors: Marks Ray
Published: July 2008

Objectives: To identify the prevalence of overweight among community‐dwelling adults diagnosed as having knee osteoarthritis (OA) and the relationship between the weight status of these individuals, selected disease‐related outcomes, and disease progression.

Research Methods and Procedures: The BMIs of 82 women and 18 men with unilateral or bilateral knee OA were examined on a single occasion along with data on physical comorbidities, pain, and function and subjected to correlation analyses. BMIs from two additional samples, one that included 16 women with and without knee OA and one that included 24 women and 6 men with knee joint OA that required surgery for the subsequent onset of hip OA, were also assessed.

Results: At least 80% of all present cohorts were overweight or obese. Those with higher BMIs reported more pain than those with lower BMIs (p < 0.05) and pain was related to perceived physical exertion (p < 0.05). Body mass indices were not significantly correlated with generic gait measures, but an inverse trend toward the time spent in the gait cycle (r = −0.63; p = 0.097) that may impact the disease process was identified. Those with comorbidities had the same body mass, on average, as those with no comorbidities, and those with bilateral disease were heavier than those with unilateral disease.

Discussion: A high body mass is present in most adults with knee OA. Moreover, being overweight may affect knee joint impact rates and pain incrementally. Having high body weights may heighten the risk for bilateral knee joint, as well as hip joint, OA.
BMI, Body Composition, and Physical Functioning in Older Adults
Authors: Woo Jean , Leung Jason , Kwok Timothy
Published: July 2008

Objective: Recent studies have emphasized the importance of muscle and fat mass in relation to age‐related decline in physical function. Our objective was to determine whether BMI, as a surrogate measurement of fat mass, may be used as a measure of risk factor for physical functioning in older adults and whether body composition measurements confer any advantage over BMI.

Research Methods and Procedures: Four thousand men and women ≥65 years of age living in the community, stratified by age and sex, underwent the following measurements: body composition by DXA; grip strength; and timed 6‐m walk. Subjects were grouped into five categories of BMI using Asian criteria for health‐related risks, and between‐group differences in physical performance measures and body composition were analyzed using analysis of covariance adjusting for age, physical activity level, and presence of chronic disease.

Results: Subjects in the two obese categories had a significantly greater number of instrumental activities of daily living (IADL) impairments compared with the underweight and normal‐weight groups. Those with BMI ≥30 kg/m2 had the worst walking performance, and the groups with BMI in the normal and overweight range had optimal performance. Fat mass, but not appendicular muscle mass, was associated with walking speed after adjusting for BMI.

Discussion: Fat mass seems to be a more important factor than appendicular muscle mass in determining walking speed in community‐living older adults, even after adjusting for BMI.
Adiponectin Receptor 1 Variants Associated with Lower Insulin Resistance in African Americans
Authors: Crimmins Nancy A. , Woo Jessica G. , Kaushal Ritesh D. , Deka Ranjan , Dolan Lawrence M. , Martin Lisa J.
Published: July 2008

Adiponectin has been shown to have a role in insulin resistance. However, little is known about the contribution of genetic variation in the adiponectin receptor 1 gene (ADIPOR1) in this regard. We hypothesized that variation in ADIPOR1 would be associated with significant changes in insulin resistance and tested this hypothesis in a cohort of 483 African‐American adolescents. Seven single nucleotide polymorphisms (SNPs) of ADIPOR1 spanning from the promoter to the 3′‐untranslated region were genotyped. We analyzed single SNPs and haplotypes for associations with insulin resistance [homeostasis model assessment of insulin resistance (HOMA‐IR)] in the full cohort as well as lean (BMI < 85%) and non‐lean (BMI ≥ 85%) subsets. There was no evidence of ADIPOR1 variant effects on HOMA‐IR in the full cohort or in the lean subset. However, in the non‐lean subset, SNP +5843 (A allele), and haplotypes including SNPs −8505/−5692/+3002/+5843 (ATTA and AGTG) showed significant associations with decreased HOMA‐IR after adjustment for sex, puberty, adiponectin, and waist z‐score. Our findings suggest not only that ADIPOR1 variants influence insulin resistance in the presence of adiposity, but also that these variants and haplotypes are protective in African Americans.
BMI and Waist Circumference as Indicators of Health Among Samoan Women
Authors: Novotny Rachel , Nabokov Vanessa , Derauf Christopher , Grove John , Vijayadeva Vinutha
Published: July 2008

Objective: High rates of obesity and chronic disease make establishment of effective indicators of risk for chronic disease important. The objective was to examine adequacy of anthropometric cut‐off points as indicators of risk for chronic disease among Samoan women in Hawaii.

Research Methods and Procedures: A cross‐sectional survey of 55 Samoan women 18 to 28 years of age that included blood lipids, cholesterol, and glucose (including after a 2‐hour oral glucose test); anthropometry (weight, height, waist circumference); and DXA of body composition.

Results: Using the Centers for Disease Control and Prevention (CDC)/World Health Organization (WHO) cut‐off points for BMI, 22% of women were overweight and 58% were obese. Cholesterol, lipid, and glucose values were all linearly related to DXA body fat, BMI, and waist circumference. BMI and waist circumference at WHO/NIH cut‐off points predicted levels of blood lipids and glucose that indicate elevated risk for disease.

Discussion: WHO/NIH cut‐off points for BMI and waist circumference reflect risk indicators of chronic disease among young Samoan women in Hawaii.
Adiposity, Physical Activity, and Physical Fitness Among Children From Aragón, Spain
Authors: Ara Ignacio , Moreno Luis A. , Leiva Maria T. , Gutin Bernard , Casajús José A.
Published: July 2008

Objective: The main purpose of this study was to determine the relationship between physical activity (PA) levels and adiposity. The secondary purpose was to assess the effect of physical fitness and living area on adiposity.

Research Methods and Procedures: A cross‐sectional study was carried out in a regional representative sample of 1068 children 7 to 12 years of age. Anthropometric and physical fitness values (including BMI, aerobic capacity, strength levels, velocity assessment, and flexibility) were measured in all children.

Results: The prevalence of being overweight and obese in the entire sample was 31% and 6%, respectively. No difference between urban and rural children was found. The proportion of boys who were classified as overweight and obese was similar in physically active and sedentary (non‐physically active) groups. However, physically active girls tended to show lower obesity prevalence compared with their sedentary counterparts (p = 0.06). In girls, the sum of the 6 skinfolds thickness (SSF) measurements was lower in the physically active group when compared with the non‐physically active group (p < 0.05); however, this effect was not observed in boys. Multiple regression analysis revealed that the level of physical activity (PA) had a significant effect on BMI and SSF in boys but not in girls, while maximal oxygen uptake (Vo2max) was significantly related to adiposity in both sexes.

Discussion: Regular participation in at least 2 hours per week of sports activities on top of the compulsory education program is associated with better physical fitness and lower whole body adiposity. In the children included in our study, among all physical fitness variables, Vo2max showed the strongest relationship with BMI and fat mass assessed by means of skinfold measurements.
Adipokine and Insulin Profiles Distinguish Diabetogenic and Non‐diabetogenic Obesities in Mice
Authors: Leiter Edward H. , Reifsnyder Peter C. , Xiao Qiang , Mistry Jehangir
Published: July 2008

Objective: To use longitudinal profiling of plasma adipokines to distinguish diabetogenic vs. non‐diabetogenic obesity syndrome in two new mouse models of polygenic obesity.

Research Methods and Procedures: Male mice of the NONcNZO5 strain develop a polygenic obesity syndrome uncomplicated by diabetes, whereas NONcNZO10 males develop a comparable polygenic obesity that precipitates type 2 diabetes. A multiplex immunoassay for simultaneous measurement of insulin and a panel of mouse adipokines (leptin, resistin, adiponectin, interleukin‐6, tumor necrosis factor α, macrophage chemoattractant protein‐1, plasminogen activator inhibitor‐1) were used to profile longitudinal changes in these strains between 4 and 16 weeks of age that might distinguish the non‐diabetogenic vs. diabetogenic obesity (diabesity).

Results: Both strains became adipose, with NONcNZO5 males attaining a higher mean body weight with a higher percentage fat content. Weight gain in NONcNZO5 was accompanied by a transient peak in plasma insulin (PI) at 8 weeks followed by a decline into normal range, with normoglycemia maintained throughout. In contrast, NONcNZO10 showed no early PI secretory response because both body weight and plasma glucose increased between 4 and 8 weeks. Only after 12 weeks, with hyperglycemia established, was a delayed PI secretory response observed. Neither plasma leptin nor adiponectin concentrations significantly differentiated the two syndromes over time. However, repeated measures ANOVA showed that NONcNZO10 males maintained significantly higher plasma concentrations of two adipokines, resistin and plasminogen activator inhibitor‐1, and the pro‐inflammatory cytokine/adipokine macrophage chemoattractant protein‐1.

Discussion: Longitudinal profiling of PI and adipokines in two new mouse models developing moderate obesity demonstrated that specific marker signatures differentiated a non‐diabetogenic obesity from a diabetogenic obesity.
Overeating by Young Obesity‐prone and Lean Rats Caused by Tastes Associated With Low Energy Foods
Authors: Pierce W. David , Heth C. Donald , Owczarczyk Joanna C. , Russell James C. , Proctor Spencer D.
Published: July 2008

Objective: Childhood obesity is a prominent health problem that may involve early learning about tastes and the energy content of foods. We tested the hypothesis that food tastes predictive of low energy content cause overeating in young animals.

Research Methods and Procedures: Juvenile and adolescent (4‐ and 8‐week‐old) male JCR:LA‐cp lean (+/cp or +/+) and obesity‐prone (cp/cp) rats were given sweet (saccharin) and salty (sodium chloride) gelatin cubes made with starch (high caloric) or no starch (low caloric) for 16 days of taste conditioning. After 10 hours of food deprivation, rats received pre‐meals with flavors that had been paired or unpaired with high caloric content during taste conditioning, followed immediately by measurement of chow intake at regular meals.

Results: Our findings show that both lean (+/cp) and obesity‐prone (cp/cp) juvenile rats ate more regular chow after a pre‐meal with a flavor associated with low caloric value than after a similar pre‐meal with a flavor predictive of high caloric content. This effect occurred with juvenile rats but not with adolescents.

Discussion: Data from our study indicate that the subversion of the relationship between taste and caloric content disrupts the normal physiological and behavioral energy balance of juvenile rats, resulting in overeating that is independent of genetic disposition for obesity.
Extreme Obesity Reduces Bone Mineral Density: Complementary Evidence from Mice and Women
Authors: Núñez Nomelí P. , Carpenter Catherine L. , Perkins Susan N. , Berrigan David , Jaque S. Victoria , Ingles Sue Ann , Bernstein Leslie , Forman Michele R. , Barrett J. Carl , Hursting Stephen D.
Published: July 2008

Objective: To evaluate the effects of body adiposity on bone mineral density in the presence and absence of ovarian hormones in female mice and postmenopausal women.

Research Methods and Procedures: We assessed percentage body fat, serum leptin levels, and bone mineral density in ovariectomized and non‐ovariectomized C57BL/6 female mice that had been fed various calorically dense diets to induce body weight profiles ranging from lean to very obese. Additionally, we assessed percentage body fat and whole body bone mineral density in 37 overweight and extremely obese postmenopausal women from the Women's Contraceptive and Reproductive Experiences study.

Results: In mice, higher levels of body adiposity (>40% body fat) were associated with lower bone mineral density in ovariectomized C57BL/6 female mice. A similar trend was observed in a small sample of postmenopausal women.

Discussion: The complementary studies in mice and women suggest that extreme obesity in postmenopausal women may be associated with reduced bone mineral density. Thus, extreme obesity (BMI > 40 kg/m2) may increase the risk for osteopenia and osteoporosis. Given the obesity epidemic in the U.S. and in many other countries, and, in particular, the rising number of extremely obese adult women, increased attention should be drawn to the significant and interrelated public health issues of obesity and osteoporosis.
Amylin and Its Relation to Insulin and Lipids in Obese Children Before and After Weight Loss
Authors: Reinehr Thomas , de Sousa Gideon , Niklowitz Petra , Roth Christian L.
Published: July 2008

Objective: There are limited data concerning the relationships between amylin, weight status, lipids, insulin, and insulin resistance in obese humans. Therefore, the aim was to study these relationships in cross‐sectional and longitudinal analyses.

Research Methods and Procedures: Fasting amylin, insulin, glucose, triglycerides, low‐density lipoprotein (LDL)‐ and high‐density lipoprotein (HDL)‐cholesterol, and percentage body fat based on skinfold measurements were determined in 37 obese children (median age, 11.5 years) and compared with 16 lean children of the same age and gender. Furthermore, we analyzed the changes of these variables in the obese children after participating in a one‐year weight loss intervention program.

Results: Obese children had significantly (p < 0.01) higher amylin, triglycerides, LDL‐cholesterol, and insulin levels as compared with the lean children. In multiple linear regression analysis, amylin was significantly (p < 0.05) correlated to insulin and triglycerides, but not to age, gender, pubertal stage, or BMI. Changes of amylin correlated significantly (p < 0.001) to changes of insulin (r = 0.54) and triglycerides (r = 0.49), but not to changes of BMI or percentage body fat. Substantial weight loss in 17 children led to a significant (p < 0.05) decrease of amylin, triglycerides, and insulin, in contrast to the 20 children without substantial weight loss.

Conclusion: Amylin levels were related to insulin concentrations in both cross‐sectional and longitudinal analyses, suggesting a relationship between amylin and insulin secretion. Amylin levels were reversibly increased in obesity and related to triglyceride concentrations.
Evidence of Linkage and Association with Body Fatness and Abdominal Fat on Chromosome 15q26
Authors: Bouchard Luigi , Bouchard Claude , Chagnon Yvon C. , Perusse Louis
Published: July 2008

Objective: In the present study, we undertook a two‐step fine mapping of a 20‐megabase region around a quantitative trait locus previously reported on chromosome 15q26 for abdominal subcutaneous fat (ASF) in an extended sample of 707 subjects from 202 families from the Quebec Family Study.

Research Methods and Procedure: First, 19 microsatellites (in addition to the 7 markers initially available on 15q24‐q26; total = 26) were genotyped and tested for linkage with abdominal total fat, abdominal visceral fat, and ASF assessed by computed tomography and with fat mass (FM) using variance component‐based approach on age‐ and sex‐adjusted phenotypes. Second, 16 single nucleotide polymorphisms (SNPs) were genotyped and tested for association using family‐based association tests.

Results: After the fine mapping, the peak logarithm of odds ratio (LOD) score (marker D15S1004) increased from 2.79 to 3.26 for ASF and from 3.52 to 4.48 for FM, whereas for abdominal total fat, the peak linkage (marker D15S996) decreased from 2.22 to 1.53. No evidence of linkage was found for abdominal visceral fat. Overall, for genotyped SNPs, three variants located in the putative MCTP2 gene were significantly associated with FM and the three abdominal fat phenotypes (p ≤ 0.05). The major allele and genotype of rs1424695 were associated with higher adiposity values (p < 0.004). The same trend was found for the two other polymorphisms (p < 0.05). None of the other SNPs was associated with adiposity phenotypes. The linkage for FM became non‐significant (LOD = 0.84) after adjustment for the MCTP2 polymorphisms, whereas the one for ASF remained unchanged.

Discussion: These results suggest that the MCTP2 gene, located on chromosome 15q26, influences adiposity. Other studies will be needed to investigate the function of the MCTP2 gene and its role in obesity.
Ten Months of Exercise Improves General and Visceral Adiposity, Bone, and Fitness in Black Girls
Authors: Barbeau Paule , Johnson Maribeth H. , Howe Cheryl A. , Allison Jerry , Davis Catherine L. , Gutin Bernard , Lemmon Christian R.
Published: July 2008

Objective: The goal of this study was to evaluate the impact of a 10‐month after‐school physical activity (PA) program on body composition and cardiovascular (CV) fitness in young black girls.

Research Methods and Procedures: Subjects were 8‐ to 12‐year‐olds recruited from elementary schools. Body composition was measured using anthropometrics {waist circumference and BMI, DXA [percentage body fat (%BF)] and bone mineral density (BMD)}, and magnetic resonance imaging [visceral adipose tissue (VAT)]. CV fitness was measured using a graded treadmill test. The intervention consisted of 30 minutes homework/healthy snack time and 80 minutes PA (i.e., 25 minutes skills instruction, 35 minutes aerobic PA, and 20 minutes strengthening/stretching). Analyses were adjusted for age, baseline value of the dependent variable, and sexual maturation (pediatrician observation).

Results: Mean attendance was 54%. Compared with the control group, the intervention group had a relative decrease in %BF (p < 0.0001), BMI (p < 0.01), and VAT (p < 0.01) and a relative increase in BMD (p < 0.0001) and CV fitness (p < 0.05). Higher attendance was associated with greater increases in BMD (p < 0.05) and greater decreases in %BF (p < 0.01) and BMI (p < 0.05). Higher heart rate during PA was associated with greater increases in BMD (p < 0.05) and greater decreases in %BF (p < 0.005).

Discussion: An after‐school PA program can lead to beneficial changes in body composition and CV fitness in young black girls. It is noteworthy that the control and intervention groups differed in change in VAT but not waist circumference. This suggests that changes in central adiposity can occur in response to PA, even in young children, but that waist circumference may not be a good indicator of central adiposity.
Erythrocyte Hyperaggregation in Obesity: Determining Factors and Weight Loss Influence
Authors: Solá Eva , Vayá Amparo , Corella Dolores , Santaolaria Maria‐Luisa , España Francisco , Estellés Amparo , Hernández‐Mijares Antonio
Published: July 2008

Objective: To compare erythrocyte aggregation (EA) in patients with severe obesity without other cardiovascular risk factors with a control group, using the Myrenne and the Sefam aggregometers, and to evaluate the effect of weight loss on this parameter.

Research Methods and Procedures: This was a longitudinal, clinical intervention study of a very low‐calorie diet for 4 weeks followed by a low‐calorie diet for 2 months. In 67 severely obese patients, an anthropometric and analytical evaluation [plasmatic lipids, fibrinogen (Fbg), and EA] was performed at baseline and 3 months after diet. The same determinations were performed in 67 normal‐weight volunteers. EA was measured with the Myrenne MA1, which determines EA at stasis (EA0) and at a low shear of 3 seconds−1 (EA1), and the Sefam aggregometer, which determines aggregation index at 10 seconds−1 (IA10), aggregation time (Ta), and disaggregation threshold (γD). Insulin resistance (IR) was calculated by homeostasis model assessment.

Results: Obese patients showed higher Fbg levels, EA0, EA1, IA10, and γD values, and lower Ta values. Differences between obese patients and control group for EA0, EA1, Ta, IA10, and γD disappeared after adjusting for BMI or for homeostasis model assessment but were maintained after adjusting for Fbg or low‐density lipoprotein‐cholesterol. Obese patients with IR showed higher EA0 and EA1 values. After weight loss, EA1 showed a significant improvement.

Discussion: Obese patients show increased EA. Erythrocyte hyperaggregation does not seem to be related to a high Fbg level or to an abnormal lipid profile but to IR. Hyperagreggation improves after weight loss.
Fatness, Fitness, and Insulin Sensitivity Among 7‐ to 9‐Year‐Old Children
Authors: Eisenmann Joey C. , DuBose Katrina D. , Donnelly Joseph E.
Published: July 2008

Objective: The purpose of this study was to examine the relationships among fatness and aerobic fitness on indices of insulin resistance and sensitivity in children.

Research Design and Methods: A total of 375 children (193 girls and 182 boys) 7 to 9 years of age were categorized by weight as normal‐weight, overweight, or obese and by aerobic fitness based on a submaximal physical working capacity test (PWC). Fasting blood glucose (GLU) and insulin (INS) were used to calculate various indices of insulin sensitivity (GLU/INS), the homeostasis model assessment (HOMA), and the quantitative insulin sensitivity check index (QUICKI). Surrogate measures of pancreatic β cell function included the insulinogenic index (INS/GLU) and the HOMA estimate of pancreatic β‐cell function (HOMA %B).

Results: Insulin sensitivity and secretion variables were significantly different between the normal‐weight children and the overweight and obese subjects. Fasting insulin (FI), HOMA, QUICKI, and INS/GLU were significantly different between the overweight and obese subjects. Likewise, the high fitness group possessed a better insulin sensitivity profile. In general, the normal‐weight–high fit group possessed the best insulin sensitivity profile and the obese‐unfit group possessed the worst insulin sensitivity profile. Several significant differences existed among the six fat‐fit groups. Of particular note are the differences within BMI groups by fitness level and the comparison of values between the normal‐weight–unfit subjects and the overweight and obese subjects with high fitness.

Conclusions: The results indicate that aerobic fitness attenuates the difference in insulin sensitivity within BMI categories, thus emphasizing the role of fitness even among overweight and obese children.
Expression and Secretion of the Atrial Natriuretic Peptide in Human Adipose Tissue and Preadipocytes
Authors: Garruti Gabriella , Giusti Vittorio , Nussberger Jürg , Darimont Christian , Verdumo Chantal , Amstutz Catherine , Puglisi Francesco , Giorgino Francesco , Giorgino Riccardo , Cotecchia Susanna
Published: July 2008

Objective:Atrial natriuretic peptide (ANP) is a secretory hormone displaying diuretic, natriuretic, and vasorelaxant activities. Recently, its lipolytic activity has been reported. Since the expression of ANP in adipose tissue has not been documented, we used real‐time reverse transcriptase polymerase chain reaction (RT‐PCR) to investigate the expression of ANP in human adipose tissue and preadipocytes.

Research Methods and Procedures:RNA was extracted from the human adipose tissue of severely obese premenopausal women as well as from human preadipocytes. For human preadipocytes, two cell systems were investigated: the human preadipose immortalized (Chub‐S7) cells, a well‐characterized human preadipose cell line, and primary preadipocytes derived from the stromal vascular fraction of the human adipose tissue. We measured the mRNA of ANP, of corin (a transmembrane serine protease involved in the conversion of pro‐ANP to ANP) and of uncoupling protein 2 (UCP2; a control gene known to be ubiquitously expressed). The expression of ANP was also investigated using immunofluorescence and radioimmunoassay in Chub‐S7 cells and human primary preadipocytes in culture.

Results:Our results indicate that ANP and corin are expressed at the mRNA level in human adipose tissue and preadipocytes. Immunofluorescence experiments demonstrated that pro‐ANP was expressed in Chub‐S7 cells. In addition, ANP secretion could be measured in Chub‐S7 cells and human primary preadipocytes in culture. Rosiglitazone, a selective peroxisome proliferator‐activated receptor type γ (PPAR‐γ) agonist promoting adipocyte differentiation, was found to modulate both ANP expression and secretion in preadipocytes.

Discussion:Our findings suggest the existence of an autocrine/paracrine system for ANP in the human adipose tissue whose implications in lipolysis and cardiovascular function need to be further explored.
Hepatic Steatosis and Increased Adiposity in Mice Consuming Rapidly vs. Slowly Absorbed Carbohydrate
Authors: Scribner Kelly B. , Pawlak Dorota B. , Ludwig David S.
Published: July 2008

Objective: Non‐alcoholic fatty liver disease (NAFLD) is fast becoming a major public health concern, coincident with the increasing prevalence of obesity. Although lifestyle greatly influences development of NAFLD, the specific dietary causes remain largely unknown. The purpose of this study was to determine whether a diet high in rapidly absorbed carbohydrate (RAC) vs. slowly absorbed carbohydrate (SAC), controlled for confounding dietary factors, causes NAFLD in mice with similar body weight. An animal model was chosen because of logistical and ethical challenges to conducting this study in humans.

Research Methods and Procedures: Male 129SvPas mice were fed diets high in either RAC (amylopectin; high glycemic index) or SAC (amylose; low glycemic index) for 25 weeks. Diets were controlled for macronutrient and micronutrient content, differing only in starch type. Body weight and composition were measured throughout the study. Hepatic and plasma triacylglycerol concentrations were quantified at the end of the study.

Results: Body weight was not significantly different between the two groups. However, total body adiposity increased twice as much, in absolute terms, in the mice fed RAC vs. SAC (12.2 ± 2.9% vs. 6.1 ± 4.2%, p < 0.0001). Hepatic triacylglycerol content was 2‐fold greater in the RAC group (20.7 ± 9.4 vs. 9.6 ± 4.9 mg/g, p = 0.01). In addition, plasma insulin and triacylglycerol concentrations were higher in the RAC group.

Discussion: A diet high in RAC causes accumulation of fat in liver, adipose tissue, and plasma in mice. Therefore, a low glycemic index diet may help prevent or treat NAFLD in humans.
Integrin Expression and H2O2 Production in Circulating and Splenic Leukocytes of Obese Rats
Authors: Kim Choong H. , Vaziri Nosratola D. , Rodriguez‐Iturbe Bernardo
Published: July 2008

Objective: Obesity is associated with oxidative stress and inflammation. We hypothesized that the pro‐inflammatory state in obesity may result in spontaneous activation and, hence, increased generation of reactive oxygen species (ROS) and integrin expression in the circulating leukocytes.

Methods: Flow cytometry was used to determine integrin expression (immunostaining) as well as superoxide and hydrogen peroxide productions (fluorescent probes) in the peripheral blood and splenic leukocyte of 24‐week‐old male obese normotensive and not‐as‐yet diabetic Zucker rats (n = 6) and their lean counterparts (n = 6).

Results: Obese rats had hyperlipidemia and normal arterial pressure, plasma glucose, and creatinine concentrations. Nevertheless, obese rats exhibited increased hydrogen peroxide production by circulating and splenic CD4+ and CD8+ T lymphocytes and by splenic macrophages. This was accompanied by up‐regulations of CD11a expression in the peripheral blood and splenic CD4+ T cells, CD11b in circulating macrophages, and CD11a and CD18 in circulating granulocytes.

Conclusion: The study revealed direct evidence of spontaneous leukocyte activation and increased ROS generation by T lymphocytes and monocytes in the peripheral blood of obese Zucker rats before the development of diabetes or hypertension. These findings illustrate the link between obesity, oxidative stress, and inflammation.
Visceral Adiposity Is Associated with Serum Retinol Binding Protein‐4 Levels in Healthy Women
Authors: Lee Ji‐Won , Im Jee‐Aee , Lee Hye‐Ree , Shim Jae‐Yong , Youn Byung‐S. , Lee Duk‐Chul
Published: July 2008

Objective: Retinol binding protein‐4 (RBP4) has been reported to impair insulin sensitivity throughout the body. We investigated the relationship between serum RBP4 levels and adiposity indices as well as metabolic risk variables.

Research Methods and Procedure: We recruited a total of 102 healthy women 21 to 67 years old. We assessed body composition by computed tomography and divided the study population into four groups based on body weight and visceral fat area (non‐obese without visceral adiposity, non‐obese with visceral adiposity, obese without visceral adiposity, and obese with visceral adiposity). Serum RBP4 levels were measured by radioimmunoassay.

Results: Despite similar levels of total body fat, non‐obese women had lower systolic blood pressure, total cholesterol, triglyceride (TG), low‐density lipoprotein (LDL)‐cholesterol levels, insulin resistance indices, and RBP4 levels than non‐obese women with visceral adiposity and had higher high‐density lipoprotein‐cholesterol levels. Similarly, obese women without visceral adiposity had lower blood pressure, total cholesterol, TG levels, insulin resistance indices, and RBP4 levels than obese women with visceral adiposity. In addition, despite having increased body fat, obese women without visceral adiposity had lower TGs, insulin resistance indices, and serum RBP4 levels than non‐obese women with visceral adiposity. By step‐wise multiple regression analysis, visceral fat areas and LDL‐cholesterol levels independently affected RBP4 levels.

Discussion: We determined that serum RBP4 levels are independently associated with visceral fat and LDL‐cholesterol levels. These results suggest that, irrespective of body weight, visceral obesity is an independent predictor of serum RBP4 levels, and RBP4 may represent a link between visceral obesity and cardiovascular disease.