Obesity-associated Chronic Diseases Research Articles

74 Unraveling the Complexities of Obesity in Clear Cell Renal Cell Carcinoma Carcinogenesis

Abstract Background Obesity has been identified as an established risk factor in the development of clear cell renal cell carcinoma (ccRCC). ccRCC arises from the proximal convoluted tubule (PCT) of the kidney which is also the site of obesity-associated chronic kidney disease. Obesity can lead to chronic cellular insults which may lead to DNA injury and whether these mechanisms are critical to cancer initiation in the kidney is unclear. One potential way that obesity can lead to cancer is by altering lipid metabolism, including increasing circulating saturated fatty acids. In particular, palmitic acid is known to be lipotoxic to proximal tubules of the kidney. Understanding how free fatty acids initiate cancer is critical to understanding the role of obesity in cancer initiation and development. We hypothesize that chronic injury and repair due to excess FFA exposure could lead to ccRCC carcinogenesis and aim to define the metabolic phenotype of obesity associated ccRCC. Methods Using publicly available data from The KIRC Cancer Genome Atlas Program (TCGA) and clinicopathologic data, we compared the RNAseq profiles of obese (BMI >= 30) to normal weight (BMI =< 25) sample origins. Of the 337, a total of 333 had BMI available for analysis. We evaluated differences in Hallmark and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Using DESeq, we adjusted for age and sex. In vitro, HK PCT cells were cultured in DMEM+10%FBS treated with bovine serum albumin (BSA)-palmitic acid complex for 48 hrs. We measured cell viability using Alamar Blue. Results were normalized to controls with BSA only. We extracted protein and performed western blots to identify DNA damage (pATM, H2AX) and endoplasmic reticulum stress (ATF4, eFI2alpha). Results Most of the patients in our clinical data cohort are male (64.4%), while 45.4% of patients are categorized by BMI as obese and 33.2% are categorized as normal. We utilized 333 individuals from the Kyoto Encyclopedia of Genes and Genomes (KEGG) to link genomic information to pathways associated with fatty acid metabolism as well as other cancer-associated hallmark metabolic pathways. We confirmed that excess free fatty acid supplementation leads to decreased cell viability in renal proximal tubule cells and renal embryonal cells and aim to assess differences in gene expression and metabolomic variation with fatty acid supplementation. Conclusions Through the investigation of these questions, we hope to improve understanding of obesity associated ccRCC and ultimately impact oncological outcomes for patients with this cancer. Understanding changes in lipid metabolism around ccRCC initiation will help identify novel pathways for pharmacologic intervention at earlier stages of the disease. DOD CDMRP Funding: yes

Endoplasmic reticulum stress: bridging inflammation and obesity-associated adipose tissue.

Obesity presents a significant global health challenge, increasing the susceptibility to chronic conditions such as diabetes, cardiovascular disease, and hypertension. Within the context of obesity, lipid metabolism, adipose tissue formation, and inflammation are intricately linked to endoplasmic reticulum stress (ERS). ERS modulates metabolism, insulin signaling, inflammation, as well as cell proliferation and death through the unfolded protein response (UPR) pathway. Serving as a crucial nexus, ERS bridges the functionality of adipose tissue and the inflammatory response. In this review, we comprehensively elucidate the mechanisms by which ERS impacts adipose tissue function and inflammation in obesity, aiming to offer insights into targeting ERS for ameliorating metabolic dysregulation in obesity-associated chronic diseases such as hyperlipidemia, hypertension, fatty liver, and type 2 diabetes.

The link between lymphocyte subpopulations in peripheral blood and metabolic variables in patients with severe obesity.

Obesity, a public health problem, is a state of metainflammation that influences the development of chronic degenerative diseases, particularly in patients with severe obesity. The objective of this study was to evidence immunometabolic differences in patients with different degrees of obesity, including severe obesity, by determining correlations between lymphocyte subpopulations and metabolic, body composition, and clinical variables. Peripheral blood immune cells (CD4+, CD8+ memory and effector T lymphocytes) were analyzed, and measures of body composition, blood pressure, and biochemical composition (glucose, glycated hemoglobin (HbA1c), insulin, C-reactive protein (CRP), and the lipid profile) were carried out in patients with different degrees of obesity. The patients were classified according to total body fat (TBF) percentage as normal body fat, class 1 and 2 obesity, class 3 obesity, and class 4 obesity. The greater the TBF percentage, the more pronounced the differences in body composition (such as a decrease in the fat-free mass (FFM) that is defined as sarcopenic obesity) and the immunometabolic profile. There was an increase of CD3+ T lymphocytes (mainly CD4+, CD4+CD62-, and CD8+CD45RO+ T lymphocytes) and an increase in the TBF percentage (severity of obesity). The correlations between lymphocyte subpopulations and metabolic, body composition, and clinical variables demonstrated the existence of a chronic, low-intensity inflammatory process in obesity. Therefore, measuring the immunometabolic profile by means of lymphocyte subpopulations in patients with severe obesity could be useful to determine the severity of the disease and the increased risk of presenting obesity-associated chronic degenerative diseases.

Urinary Exosomal MicroRNAs as Biomarkers for Obesity-Associated Chronic Kidney Disease.

The early detection of chronic kidney disease (CKD) is key to reducing the burden of disease and rising costs of care. This need has spurred interest in finding new biomarkers for CKD. Ideal bi-omarkers for CKD should be: easy to measure; stable; reliably detected, even when interfering substances are present; site-specific based on the type of injury (tubules vs. glomeruli); and its changes in concentration should correlate with disease risk or outcome. Currently, no single can-didate biomarker fulfills these criteria effectively, and the mechanisms underlying kidney fibrosis are not fully understood; however, there is growing evidence in support of microRNA-mediated pro-cesses. Specifically, urinary exosomal microRNAs may serve as biomarkers for kidney fibrosis. In-creasing incidences of obesity and the recognition of obesity-associated CKD have increased interest in the interplay of obesity and CKD. In this review, we provide: (1) an overview of the current scope of CKD biomarkers within obese individuals to elucidate the genetic pathways unique to obesi-ty-related CKD; (2) a review of microRNA expression in obese individuals with kidney fibrosis in the presence of comorbidities, such as diabetes mellitus and hypertension; (3) a review of thera-peutic processes, such as diet and exercise, that may influence miR-expression in obesity-associated CKD; (4) a review of the technical aspects of urinary exosome isolation; and (5) future areas of research.

Correlation between body condition score and body composition in a rat model for obesity research

The incidences of obesity-associated chronic diseases are increasing worldwide. Research into the causes of obesity as well as potential treatments has highlighted the crucial role of preclinical studies using animal models. Rats are one of the most widely used species in obesity research. However, even with decades of research in both genetically obese rats and diet-induced obese rat models, definitive criteria to practically classify levels of obesity in the rat are not well established. The current study proposes new criteria modified from a 5-point body condition score (BCS) using in an animal health monitoring system and added a half-point scale to extend the range of body weight associated with subcutaneous fat deposition. The modified criteria were tested and compared with body composition from dual energy X-ray absorptiometry scans and selected adipose tissue weights. The results showed that the modified body condition scale was highly correlated with fat deposition in the rat body, particularly the visceral and inguinal fat pads. Both pads were closely related to changes in some specific landmarks used for the scale determination. These finding should extrapolate to obese rats in other models, with the advantage that data classified in BCS can pair the animal data with human body mass index. This will enhance the value of information from preclinical studies to design and predict outcomes of subsequent human clinical trials.

Examining the association between adiposity and DNA methylation: A systematic review and meta-analysis.

Obesity is associated with widespread differential DNA methylation (DNAm) patterns, though there have been limited overlap in the obesity-associated cytosine-guanine nucleotide pair (CpG) sites that have been identified in the literature. We systematically searched four databases for studies published until January 2020. Eligible studies included cross-sectional, longitudinal, or intervention studies examining adiposity and genome-wide DNAm in non-pregnant adults aged 18-75 in all tissue types. Study design and results were extracted in the descriptive review. Blood-based DNAm results in body mass index (BMI) and waist circumference (WC) were meta-analyzed using weighted sum of Z-score meta-analysis. Of the 10,548 studies identified, 46 studies were included in the systematic review with 18 and nine studies included in the meta-analysis of BMI and WC, respectively. In the blood, 77 and four CpG sites were significant in three or more studies of BMI and WC, respectively. Using a genome-wide threshold for significance, 52 blood-based CpG sites were significantly associated with BMI. These sites have previously been associated with many obesity-related diseases including type 2 diabetes, cardiovascular disease, Crohn's disease, and depression. Our study shows that DNAm at 52 CpG sites represent potential mediators of obesity-associated chronic diseases and may be novel intervention or therapeutic targets to protect against obesity-associated chronic diseases.

Maladaptive regeneration - the reawakening of developmental pathways in NASH and fibrosis.

With the rapid expansion of the obesity epidemic, nonalcoholic fatty liver disease is now the most common chronic liver disease, with almost 25% global prevalence. Nonalcoholic fatty liver disease ranges in severity from simple steatosis, a benign 'pre-disease' state, to the liver injury and inflammation that characterize nonalcoholic steatohepatitis (NASH), which in turn predisposes individuals to liver fibrosis. Fibrosis is the major determinant of clinical outcomes in patients with NASH and is associated with increased risks of cirrhosis and hepatocellular carcinoma. NASH has no approved therapies, and liver fibrosis shows poor response to existing pharmacotherapy, in part due to an incomplete understanding of the underlying pathophysiology. Patient and mouse data have shown that NASH is associated with the activation of developmental pathways: Notch, Hedgehog and Hippo-YAP-TAZ. Although these evolutionarily conserved fundamental signals are known to determine liver morphogenesis during development, new data have shown a coordinated and causal role for these pathways in the liver injury response, which becomes maladaptive during obesity-associated chronic liver disease. In this Review, we discuss the aetiology of this reactivation of developmental pathways and review the cell-autonomous and cell-non-autonomous mechanisms by which developmental pathways influence disease progression. Finally, we discuss the potential prognostic and therapeutic implications of these data for NASH and liver fibrosis.

4311 Inflammatory biomarkers of cognitive dysfunction in pediatric obesity: associations between Executive Function, C-Reactive Protein, Interleukin 6, and Tumor Necrosis Factor alpha

OBJECTIVES/GOALS: Executive function (EF) deficits lead to poorer adherence and weight loss in obesity treatment. Conversely, untreated obesity leads to both EF impairments and risk of chronic disease. EF deficits in children with obesity have begun to be associated with biomarkers of chronic disease risk such as glucose and cortisol. Elevated pro-inflammatory biomarkers, such as C-Reactive Protein (CRP), Interleukin 6 (IL-6), and Tumor Necrosis Factor a (TNFa), indicate risk for obesity-associated chronic disease and may represent another candidate biomarker of EF deficits in pediatric obesity. These inflammatory markers tend to be elevated in obesity but have yet to be examined in association with EF in pediatric obesity. This represents an opportunity to identify potential biomarkers of EF which may serve as novel treatment targets that could improve outcomes and chronic disease prevention. Thus, the present study aims to explore associations between EF and blood serum CRP, IL-6, and TNFa. METHODS/STUDY POPULATION: Treatment-seeking children aged 8-12 years with BMI>95th percentile were recruited from a pediatric weight management clinic and attended baseline assessments for a family-based behavioral intervention program for pediatric obesity. Demographics and medical history were assessed via parent questionnaire. Height and weight were measured by research staff and converted to zBMI. Child performance-based EF was assessed via the NIH Toolbox Cognitive Battery iPad application. Blood draws, assays, and Dual-energy X-ray Absorptiometry (DXA; measuring adiposity) were conducted by trained research personnel. Pearson’s correlations were conducted to explore associations between EF (NIH Toolbox Cognitive Battery, fully corrected T-scores) and CRP, IL-6, and TNFa. RESULTS/ANTICIPATED RESULTS: Children (n = 12) were primarily female (76.5%) and African American (64.7%). Correlation coefficients between inflammatory markers and EF were highly variable (r = −0.39 to 0.52). CRP showed small, negative associations with Cognitive Flexibility (r = −0.39) and Inhibitory Control (r = −0.34). IL-6 also demonstrated a small, negative association with Inhibitory Control (r = −0.37). TNFa was positively and moderately associated with working memory (r = 0.53). Remaining associations were weak (−0.3<r<0.3). DISCUSSION/SIGNIFICANCE OF IMPACT: Signals of higher inflammation, measured via CRP and IL-6, in association with EF deficits were identified in a small sample of children with obesity, as hypothesized. However, signals in the opposite direction were identified as well, measured via TNFa. CRP and IL-6 may represent candidate biomarkers of executive dysfunction in obesity that warrant further domain and biomarker-specific research, with potential long-term implications for improving pediatric obesity treatment.

Renal Changes (Structural and Functional) in The High Fat Diet-Induced Obesity and The Effect of Food Restriction: An Experimental Study

Introduction and aim: Obesity is a worldwide epidemic and nearly affects every organ. However, the renal changes in obesity are not sufficiently addressed. Thus we aimed to investigate the effects of high-fat diet induced obesity on the kidney and explore the effect of caloric restriction on the renal changes associated with obesity.
 Methodology: Thirty male albino rats, 160-180 g included and divided into three equal groups. The first is the control group (received nothing except normal diet). The second is the high fat diet-fed group, where rats fed on high fat diet for 12 weeks. The third group fed as the second one for 12 weeks followed by diet restriction for 6 weeks by feeding on normal chow diet. The following measurement were recorded: 1) Initial and final body weight, 2) serum value of different biochemical parameters (lipid profile, glucose, insulin, cytokines, inflammatory markers and renal function tests). Finally, kidney was extract, fixed and prepared for histopathological examination.
 Results: The final weight significantly increased in the obese than the control and diet restriction groups (421.0±17.13 versus 279.50±11.17 and 333.0±13.33 g, successively). The total cholesterol, TG, LDL, vLDL, glucose, insulin, HOMA-IR, IL-6, leptin, resistin, TNF-α, CRP and Plasminogen activator inhibitor-1, creatinine, urea, protein in urine, uric acid were significantly higher in obese than control and diet-restriction groups. However, HDL and adiponectin were significantly reduced in obese than the control and diet restriction groups. The diet restriction significantly improved laboratory values, but it remains significantly different than the control group. The correlation between weight gain with other variables and renal structural changes confirmed the laboratory results.
 Conclusion: Obesity is associated with functional and structural renal changes. The potential mechanisms involve inflammation, lipotoxicity and perhaps other unknown mechanisms. Weight reduction constitutes the most effective intervention to guard or treat obesity-associated chronic kidney disease.

A specific small-molecule inhibitor of protein kinase CδI activity improves metabolic dysfunction in human adipocytes from obese individuals

The metabolic consequences and sequelae of obesity promote life-threatening morbidities. PKCδI is an important elicitor of inflammation and apoptosis in adipocytes. Here we report increased PKCδI activation via release of its catalytic domain concurrent with increased expression of proinflammatory cytokines in adipocytes from obese individuals. Using a screening strategy of dual recognition of PKCδI isozymes and a caspase-3 binding site on the PKCδI hinge domain with Schrödinger software and molecular dynamics simulations, we identified NP627, an organic small-molecule inhibitor of PKCδI. Characterization of NP627 by surface plasmon resonance (SPR) revealed that PKCδI and NP627 interact with each other with high affinity and specificity, SPR kinetics revealed that NP627 disrupts caspase-3 binding to PKCδI, and in vitro kinase assays demonstrated that NP627 specifically inhibits PKCδI activity. The SPR results also indicated that NP627 affects macromolecular interactions between protein surfaces. Of note, release of the PKCδI catalytic fragment was sufficient to induce apoptosis and inflammation in adipocytes. NP627 treatment of adipocytes from obese individuals significantly inhibited PKCδI catalytic fragment release, decreased inflammation and apoptosis, and significantly improved mitochondrial metabolism. These results indicate that PKCδI is a robust candidate for targeted interventions to manage obesity-associated chronic inflammatory diseases. We propose that NP627 may also be used in other biological systems to better understand the impact of caspase-3-mediated activation of kinase activity.

Determinants of overweight and obesity among urban school-going children and adolescents: a case-control study in Bangladesh.

Childhood overweight and obesity is a major public health concern all over the world. Overweight or obese children have a higher risk of becoming obese in adulthood and are at higher risk of associated chronic diseases. The aim of this study was to determine the risk factors associated with overweight and obesity among urban school children and adolescents in Bangladesh. A case-control study was conducted among students aged 10-16 years in 10 schools of Dhaka city. A structured questionnaire was used to collect socio-demographic information and students' exposure to various risk factors. Data were analyzed by using SPSS 23. Family income (p = 0.000), mother's weight (p = 0.036), school activity (p = 0.046), total physical activity (p = 0.008), sedentary activities (p = 0.014), eating fast food (0.008) and cakes/biscuits (p = 0.018) were found as potential determinants of overweight and obesity of children and adolescents. A multiple logistic regression revealed family income >50,000 per month [adjusted odds ratio (AOR) = 3.07, p = 0.001], no physical activity (AOR = 38.3, p = 0.004), more than 4 h of sedentary activities (AOR = 4.84, p = 0.02), regular consumption of fast food (AOR = 3.05, p = 0.042) are risk factors associated with childhood overweight/obesity. Whereas, having a normal weight mother (AOR = 0.51, p = 0.037) and eating cakes/biscuits less than 3 days a week (AOR = 0.33, p = 0.02) were found as protective factors. Findings from this study will be very useful for public health professionals to increase awareness regarding risk factors of overweight and obesity, in order to reduce the future burden of obesity-associated chronic diseases.

Obesity Prevalence Among Adults Living in Metropolitan and Nonmetropolitan Counties - United States, 2016.

Approximately 46 million persons (14%) in the United States live in nonmetropolitan counties.* Compared with metropolitan residents, nonmetropolitan residents have a higher prevalence of obesity-associated chronic diseases such as diabetes (1), coronary heart disease (1), and arthritis (2). The 2005-2008 National Health and Nutrition Examination Survey (NHANES) found a significantly higher obesity prevalence among adults in nonmetropolitan (39.6%) than in metropolitan (33.4%) counties (3). However, this difference has not been examined by state. Therefore, CDC examined state-level 2016 Behavioral Risk Factor Surveillance System (BRFSS) data and found that the prevalence of obesity (body mass index [BMI] ≥30 kg/m2) was 34.2% among U.S. adults living in nonmetropolitan counties and 28.7% among those living in metropolitan counties (p<0.001). Obesity prevalence was significantly higher among nonmetropolitan county residents than among metropolitan county residents in all U.S. Census regions, with the largest absolute difference in the South (5.6 percentage points) and Northeast (5.4 percentage points). In 24 of 47 states, obesity prevalence was significantly higher among persons in nonmetropolitan counties than among those in metropolitan counties; only in Wyoming was obesity prevalence higher among metropolitan county residents than among nonmetropolitan county residents. Both metropolitan and nonmetropolitan counties can address obesity through a variety of policy and environmental strategies to increase access to healthier foods and opportunities for physical activity (4).

The Triumvirate of Adiposopathy: A Literature Review and Proposal of the Claros Pathophysiological Model

Obesity is currently considered as the 21st century epidemic. The accelerated increase in prevalence and mortality due to cardiovascular diseases establishes a historical precedent as a global public health problem. The increased incidence of obesity and obesity-associated chronic diseases (coronary heart disease, cancer, diabetes), together with the frequent finding of these conditions in the clinic, urgently call for studies aiming to identify possible pathophysiologic connections among these conditions. Obesity is often seen only as an imbalance between caloric intake and energy expenditure. On the other hand, numerous neuroendocrine factors are responsible for the regulation of energy metabolism. In addition, body metabolism is also affected by the autocrine, paracrine, and endocrine activity of organokines. Thus, the understanding signaling pathways, action and regulation of organokines could lead to a comprehensive approach to obesity, which in turn may unravel new indicators of adiposopathy, that are not necessarily associated solely to body weight or evident excess of fatty tissue. Herein we propose a pathophysiological model, which we refer to as the triumvirate of adiposopathy, involving the alteration of organokine balance (myokines, hepatokines, and adipokines) and that takes into account signaling pathways that are common to pro-inflammatory states such as insulin resistance and endothelial damage, emphasizing in adiposopathy and obesity, aiming to achieve the early identification of cardiometabolic risk, and thus positively impact the risk of morbimortality associated with adiposity.

Disruption of Lipid Raft Function Increases Expression and Secretion of Monocyte Chemoattractant Protein-1 in 3T3-L1 Adipocytes.

The adipocyte is unique in its capacity to store lipids. In addition to triglycerides, the adipocyte stores a significant amount of cholesterol. Moreover, obese adipocytes are characterized by a redistribution of cholesterol with depleted cholesterol in the plasma membrane, suggesting that cholesterol perturbation may play a role in adipocyte dysfunction. We used methyl-β-cyclodextrin (MβCD), a molecule with high affinity for cholesterol, to rapidly deplete cholesterol level in differentiated 3T3-L1 adipocytes. We tested whether this perturbation altered adipocyte secretion of monocyte chemoattractant protein-1 (MCP-1), a chemokine that is elevated in obesity and is linked to obesity-associated chronic diseases. Depletion of cholesterol by MβCD increased MCP-1 secretion as well as the mRNA and protein levels, suggesting perturbation at biosynthesis and secretion. Pharmacological inhibition revealed that NF-κB, but not MEK, p38 and JNK, was involved in MβCD-stimulated MCP-1 biosynthesis and secretion in adipocytes. Finally, another cholesterol-binding drug, filipin, also induced MCP-1 secretion without altering membrane cholesterol level. Interestingly, both MβCD and filipin disturbed the integrity of lipid rafts, the membrane microdomains enriched in cholesterol. Thus, the depletion of membrane cholesterol in obese adipocytes may result in dysfunction of lipid rafts, leading to the elevation of proinflammatory signaling and MCP-1 secretion in adipocytes.

Upregulated TNF Expression 1\xa0Year After Bariatric Surgery Reflects a Cachexia-Like State in Subcutaneous Adipose Tissue

BackgroundAdipose tissue dysfunction contributes to obesity-associated chronic diseases. In the first year after bariatric surgery, obese patients significantly improve their metabolic status upon losing weight. We aimed to investigate whether changes in subcutaneous adipose tissue gene expression reflect a restoration of a healthy lean phenotype after bariatric surgery.MethodsThirty-one severely obese patients (BMI ≥ 40 kg/m2) were examined before and after surgery. subcutaneous adipose tissue (SAT) was collected during and 1 year after bariatric surgery. SAT from 20 matched lean and overweight patients (BMI < 30 kg/m2) was collected during elective abdominal surgery. Baseline characteristics and SAT gene expression relevant to glucose and lipid metabolism, inflammation, and apoptosis were analyzed.ResultsAfter surgery, mean BMI decreased from 46.1 ± 6.3 to 31.1 ± 5.7 kg/m2 and homeostasis model assessment of insulin resistance from 5.4 ± 5.3 to 0.8 ± 0.8. SAT expression of most analyzed inflammatory cytokines, growth factors, and metabolic and cell surface markers was greatly downregulated even compared to the lean cohort. In contrast, gene expression of TNF and CASP3 was significantly upregulated. Elastic net regression analysis showed that fasting glucose levels and CASP3 predicted increased TNF expression in the post-obese group.ConclusionsGene expression patterns in SAT 1 year after bariatric surgery point to a reduced inflammation. The unexpected high TNF expression in SAT of post-obese subjects is most likely not an indicator for inflammation, but rather an indicator for increased lipolysis and adipose tissue catabolism. Notably, after bariatric surgery SAT gene expression reflects a cachexia-like phenotype and differs from the lean state.

Life-course socio-economic status and adult BMI in Ghana; analysis of the WHO study on global ageing and adult health (SAGE).

BackgroundObesity rates have continued to increase over time globally, resulting in an increase in the burden of obesity-associated chronic diseases. There is a paucity of research on the association between obesity and generational changes in socio-economic status (SES) in developing countries like Ghana, and therefore a critical need to better understand within-country differences in obesity and its association with SES over the life-course.MethodsData from a nationally representative sample of adult women in Ghana was used to examine the association between life-course SES and adult body mass index (BMI). Life-course SES was defined based on changes in the employment and education status of both parents and the study participant. Survey weighted multivariable linear regression models were used to examine the association between individual and life-course SES in relation to BMI.ResultsParticipants with higher SES over their life course, that is, both the participant and her father had at least a primary education (both > = primary vs. both < primary: BMI 27.2 vs. 24.1), and both were employed (both employed vs. both unemployed: BMI 26.5 vs. 24.4) had higher BMI compared with participants with lower SES over their life course.ConclusionHigher individual and life-course SES is associated with higher BMI among women in Ghana, although maternal employment was associated with lower BMI.

Disparities in Early Transitions to Obesity in Contemporary Multi-Ethnic U.S. Populations.

BackgroundFew studies have examined weight transitions in contemporary multi-ethnic populations spanning early childhood through adulthood despite the ability of such research to inform obesity prevention, control, and disparities reduction.Methods and ResultsWe characterized the ages at which African American, Caucasian, and Mexican American populations transitioned to overweight and obesity using contemporary and nationally representative cross-sectional National Health and Nutrition Examination Survey data (n = 21,220; aged 2–80 years). Age-, sex-, and race/ethnic-specific one-year net transition probabilities between body mass index-classified normal weight, overweight, and obesity were estimated using calibrated and validated Markov-type models that accommodated complex sampling. At age two, the obesity prevalence ranged from 7.3% in Caucasian males to 16.1% in Mexican American males. For all populations, estimated one-year overweight to obesity net transition probabilities peaked at age two and were highest for Mexican American males and African American females, for whom a net 12.3% (95% CI: 7.6%-17.0%) and 11.9% (95% CI: 8.5%-15.3%) of the overweight populations transitioned to obesity by age three, respectively. However, extrapolation to the 2010 U.S. population demonstrated that Mexican American males were the only population for whom net increases in obesity peaked during early childhood; age-specific net increases in obesity were approximately constant through the second decade of life for African Americans and Mexican American females and peaked at age 20 for Caucasians.ConclusionsAfrican American and Mexican American populations shoulder elevated rates of many obesity-associated chronic diseases and disparities in early transitions to obesity could further increase these inequalities if left unaddressed.

Impact of vitamin D supplementation on adiposity in African-Americans.

Background:African-Americans have higher rates of obesity-associated chronic diseases. Serum 25-hydroxyvitamin D (25(OH)D) shows an inverse association with obesity status. We investigated whether vitamin D supplementation changes body mass index (BMI).Subjects:In total, 328 overweight African-Americans were enrolled over three consecutive winter periods (2007–2010) into a randomized, double-blind, placebo-controlled trial to receive cholecalciferol supplementation (0, 1000 international units (IU), 2000 IU or 4000 IU per day) for 3 months. Plasma concentrations of 25(OH)D and anthropometric measurements were done at baseline, 3 and 6 months.Results:At 3 months, vitamin D supplementation in three dose groups (1000 IU, 2000 IU or 4000 IU per day) did not cause any significant changes in BMI as compared with placebo group 3-month change in BMI per 1000 IU per day estimate (SE): 0.01 (0.039); P=0.78.Conclusions:In overweight African-Americans, short-term high-dose vitamin D supplementation did not alter BMI.

Samoan body and soul: adapting an evidence-based obesity and cancer prevention program.

Obesity-associated chronic diseases persist in Samoan populations in the United States. Samoans and African Americans share cultural similarities such as church affiliation, perceptions of weight and body size, and obesity-related health risks. Adapting an effective energy balance intervention originally designed for African Americans--Body and Soul--might be useful in reducing obesity among U.S. Samoans. To determine potential attractiveness and adaptations, we used aspects of grounded theory to analyze key-informant and focus group interviews with 31 purposively selected Samoans in Hawaii. We incorporated participatory features into the research with Samoan community members conducting parts of the study. From interview narratives, we identified relevant themes from Samoan culture, such as "fa'aSamoa", or the Samoan way, and specific energy balance activities to include in an obesity and cancer prevention intervention for U.S.-dwelling Samoans. Our findings describe methods to address health disparities by incorporating culturally appropriate health concepts into existing evidence-based interventions.

Risk factors associated with overweight and obesity among urban school children and adolescents in Bangladesh: a case–control study

BackgroundChildhood obesity has become an emerging urban health problem in urban cities in Bangladesh, particularly in affluent families. Risk factors for obesity in this context have not been explored yet. The objective of this study was to identify the risk factors associated with overweight and obesity among school children and adolescents in Dhaka, Bangladesh.MethodsFrom October through November 2007, we conducted a case–control study among children aged 10–15 years in seven schools in Dhaka. We assessed body mass index (weight in kg/height in sq. meter) to identify the cases (overweight/obese) and controls (healthy/normal weight) following the Centers for Disease Control and Prevention age and sex specific growth chart. We used a structured questionnaire to collect demographic information and respondent’s exposure to several risk factors such as daily physical activity at home and in school, hours spent on computer games and television watching, maternal education level and parents’ weight and height.ResultsWe enrolled 198 children: 99 cases, 99 controls. Multiple logistic regression analysis revealed that having at least one overweight parent (OR = 2.8, p = 0.001) and engaging in sedentary activities for >4 hours a day (OR = 2.0, p = 0.02) were independent risk factors for childhood overweight and/or obesity while exercising ≥ 30 minutes a day at home was a protective factor (OR = 0.4, p = 0.02). There were no significant associations between childhood overweight and sex, maternal education or physical activity at school.ConclusionHaving overweight parents along with limited exercise and high levels of sedentary activities lead to obesity among school children in urban cities in Bangladesh. Public health programs are needed to increase awareness on risk factors for overweight and obesity among children and adolescents in order to reduce the future burden of obesity-associated chronic diseases.