Author Interviews, Circadian Rhythm, Gastrointestinal Disease, Genetic Research, Weight Research / 13.10.2019

MedicalResearch.com Interview with: Marco Colonna, MD Robert Rock Belliveau MD Professor Pathology & Immunology Washington University School of Medicine Qianli Wang MD-PhD Student MSTP student Washington University School of Medicine MedicalResearch.com: What is the background for this study? Response: Many aspects of the mammalian digestive system including gut motility, nutrient absorption, and microbiota follow a daily rhythm. This circadian rhythm is generated by the cyclic expressions of molecular clock genes thought to be present in most cells. Group 3 innate lymphoid cells (ILC3) are lymphocytes residing in the intestinal mucosa that respond rapidly to activation in both homeostatic and inflammatory settings. Namely, ILC3s help maintain the mucosal barrier, regulate epithelial lipid transport, and protect against bacterial enteric infections. As tissue resident cells within the highly dynamic and rhythmic environment of the intestine, it may be advantageous for ILC3s to also be synchronized with the circadian rhythm.  (more…)
Author Interviews, Nutrition, Pediatrics, Sugar, Weight Research / 26.09.2019

MedicalResearch.com Interview with: Professor Alex Bentley Head of Anthropology University of Tennessee Knoxville TN  MedicalResearch.com: What is the background for this study? What are the main findings? Response: In recent years, considerable evidence has accumulated suggesting that excess sugar consumption, e.g. in sugar-sweetened beverages, has been a major driver of the U.S. obesity crisis. Critics of this idea, however, have asked: why did the rise in sugar consumption precede the U.S. obesity crises by a decade or more, and why did obesity continue to rise even after sugar consumption began declining the early 2000s? We modeled the delayed onset of obesity by assuming that diet is a cumulative process that begins in childhood. On average, each age cohort (birth year) has its own specific cumulative exposure to excess sugar in their diets.  The inherent delay in our model links childhood consumption of excess sugar with propensity for adult obesity as an adult. Our model explains a simple process by which excess sugar in diets of children of the 1970s and 1980s could explain the sharp increase of adult obesity that began in the 1990s. (more…)
Author Interviews, BMJ, Brigham & Women's - Harvard, Nutrition, Weight Research / 24.09.2019

MedicalResearch.com Interview with: Deirdre K Tobias, ScD Associate Epidemiologist, Brigham and Women’s Hospital Assistant Professor, Harvard Medical School nuts-nutrition-weight-obesityMedicalResearch.com: What is the background for this study? What types of nuts are helpful? Peanuts included?  Response: We did not have the granularity in our study to evaluate too many individual nut types, and did not perform head-to-head comparisons between types of nuts. All seemed to be better for long-term weight control compared with the snacks like potato chips that we know are not great for us on a regular basis. (more…)
Author Interviews, Gastrointestinal Disease, Weight Research / 21.09.2019

MedicalResearch.com Interview with: Sarah Ballou, PhD Health Psychologist Division of Gastroenterology, Hepatology, and Nutrition Beth Israel Deaconess Medical Center Boston, MA MedicalResearch.com: What is the background for this study? What are the main findings? Response: Obesity is known to be associated with an increased risk of gastrointestinal and liver diseases, but less is known about the relationship between obesity and constipation or diarrhea. We used a nationally representative sample of the US population to evaluate whether obesity was associated with abnormal bowel habits. We found that obese individuals were 60% more likely to have diarrhea, even after controlling for possible confounding factors such as dietary, lifestyle, psychological, and medical conditions. (more…)
Author Interviews, Cancer Research, Cleveland Clinic, Weight Research / 15.08.2019

MedicalResearch.com Interview with: Siran M. Koroukian, PhD Director, Population Cancer Analytics Shared Resource Case Comprehensive Cancer Center Director, Population Health and Outcomes Research Core Associate Professor Department of Population and Quantitative Health Sciences School of Medicine Case Western Reserve University Cleveland, OH MedicalResearch.com: What is the background for this study? What are the main findings? Response: Previous studies have shown that obesity-associated cancers (OACs) have been increasing in younger people. Using data from over 6 million cancer cases from 2000-2016, we identified the specific age/sex/race-ethnicity groups that were most affected by increases in OACs. We found a substantial shift of obesity-associated cancers to younger age groups, with the most notable increases occurring to the 50-64 age group. In addition, we observed the greatest percentage increase in the number of OAC cases during the study period in Hispanic men and women, as well as for cancers of the thyroid, gallbladder, liver and intrabiliary duct. (more…)
Annals Internal Medicine, Author Interviews, Race/Ethnic Diversity, Weight Research / 13.08.2019

MedicalResearch.com Interview with: Jonathan Emberson, PhD Associate Professor (Medical Statistics and Epidemiology) Deputy Director of Graduate Studies Medical Research Council Population Health Research Unit Clinical Trial Service Unit & Epidemiological Studies Unit Nuffield Department Population Health University of Oxford    MedicalResearch.com: What is the background for this study? Response: Some previous studies had claimed that being overweight is not strongly associated with mortality in Hispanic populations (the ‘Hispanic paradox’). However, these studies had not accounted for the fact that while obesity makes diabetes and several other chronic diseases more common, these diseases may then result in substantial weight loss, thereby hiding the reason why those diseases arose in the first place.  (more…)
Author Interviews, Dermatology, Weight Research / 12.08.2019

MedicalResearch.com Interview with: Prof Ching-Chi Chi, MD, MMS, DPhil (Oxford) Department of Dermatology Chang Gung Memorial Hospital, Linkou Taiwan MedicalResearch.com: What is the background for this study?   Response: Psoriasis has been associated various inflammatory comorbidities including diabetes mellitus, coronary artery disease, etc. Moreover, obesity is prevalent among psoriasis patients and has been considered as an independent risk factor for occurrence and worsening of psoriasis by promoting systemic inflammation. Notably, body weight (BW) gain of psoriasis patients after biologics use has been observed. However, there are inconsistent reports on whether biological therapy relates to BW gain.  (more…)
Author Interviews, Environmental Risks, NYU, Pediatrics, Weight Research / 26.07.2019

MedicalResearch.com Interview with: Melanie Jacobson, PhD, MPH NYU School of Medicine New York, N.Y.  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Our study was about exposure to bisphenols, which are synthetic chemicals found in aluminum can linings, plastics, thermal paper receipts and other consumer products, and their association with obesity among a nationally representative sample of US children and adolescents. We found that children who had greater levels of these chemicals in their urine were more likely to be obese compared with children with lower levels. (more…)
Author Interviews, JAMA, Menopause, Weight Research / 25.07.2019

MedicalResearch.com Interview with: Yangbo Sun  MD, PhD Department of Epidemiology University of Iowa Wei Bao, MD, PhD Assistant Professor, Department of Epidemiology College of Public Health, University of Iowa Iowa City, IA 52242 MedicalResearch.com: What is the background for this study? What are the main findings? Response: Obesity has become a serious health problem in the United States. Body mass index (BMI) which is calculated as weight (kg)/height (m)2, is the standard measure used to define obesity in clinical and public health guidelines. However, BMI does not distinguish body shape or body fat distribution. Meanwhile central obesity, characterized by relatively high abdominal fat distribution, has been associated with higher risk of mortality, independent of BMI. So for example, two persons with the same BMI of 24 which is considered as “normal weight”, might have different abdominal fat distribution, thus they might be facing different risk of developing disease and mortality. In the most recent obesity management guidelines, measuring central obesity was recommended among people who are either overweight or have class I obesity (BMI 25.0-34.9 kg/m2), but not among people of normal weight. This might send those people with normal weight but with high abdominal fat as well as those public and clinical professionals a wrong message that these people are free of any particular obesity-related risk, while in fact, they are at elevated risk of mortality and might need risk reduction interventions, such as lifestyle modifications and other interventions. So we did this study to evaluate the mortality risk among this neglected group of people. We found that women with normal weight central obesity were at increased risk of mortality. (more…)
Author Interviews, Brigham & Women's - Harvard, JAMA, Nutrition, Weight Research / 22.07.2019

MedicalResearch.com Interview with: Frank Qian, MPH Department of Nutrition Harvard T. H. Chan School of Public Health Boston, Massachusetts MedicalResearch.com: What is the background for this study? Response: Plant-based diets have really grown in popularity in the last several years, particularly among the younger generation in the United States, many of whom are adopting a plant-based or vegetarian/vegan diet. However, the quality of such a diet can vary drastically. While many prior studies have demonstrated beneficial associations for risk of type 2 diabetes with healthful plant-based foods such as fruits, vegetables, nuts/seeds, whole grains, and legumes, the opposite is true for less healthful plant-based foods such as potatoes and refined grains such as white rice. In addition, some animal-based foods, such as dairy and fish, have shown protective associations against the development of type 2 diabetes, so strict vegetarian diets which exclude these foods may miss out on the potential benefits. Given these divergent findings, we sought to pool all the available data from prior cohort studies to analyze whether the overall association of a diet which emphasizes plant-based foods (both healthful and unhealthful) are related to risk of type 2 diabetes. (more…)
Author Interviews, JAMA, Nutrition, Weight Research / 11.07.2019

MedicalResearch.com Interview with: Anne Thorndike, MD, MPH Massachusetts General Hospital General Internal Medicine Division Boston, MA 02114 MedicalResearch.com: What is the background for this study? Response: Nearly one-third of the 150 million US adults who are employed are obese. Employees frequently eat meals acquired at work, and workplace food is often high in calories. Effective strategies for reducing non-nutritive energy intake during the workday could help address the rising prevalence of obesity. Simplified labeling, such as traffic-light labels, provide understandable information about the relative healthfulness of food and can be placed on menu boards, shelf labels, and individual packages to help employees make healthier choices. Choice architecture (e.g., product placement) interventions make it easier and more convenient for employees to choose a healthy item. It is unknown if labeling interventions are associated with sustained reductions in calorie intake, or if there are only temporary effects after which most people revert to higher-calorie choices. A previous study demonstrated that a hospital cafeteria traffic-light labeling and choice architecture program resulted in a higher proportion of healthy green-labeled purchases and lower proportion of unhealthy red-labeled purchases over two years. The current study analyzed calories purchased by a longitudinal cohort of 5,695 hospital employees who used the cafeteria regularly. The study examined changes in calories purchased over time and hypothesized the effect of the change in calorie intake on employees’ weight. (more…)
Aging, Author Interviews, Cognitive Issues, Gender Differences, Hormone Therapy, JAMA, Menopause, Weight Research / 05.07.2019

MedicalResearch.com Interview with: Rachel Zsido PhD student Department of Neurology International Max Planck MedicalResearch.com: What is the background for this study? Response: We integrated measures of brain network structure, visceral adipose tissue (VAT), serum estradiol levels, and cognitive performance from 974 participants in order to shed light on potential mechanisms underlying cognitive health. We believe it is imperative to assess sex-specific risk trajectories in brain aging and cognitive decline, especially given the known sex differences in both VAT accumulation patterns and estradiol fluctuations across the lifespan. Thus, we aimed to answer three questions in men and in women: 1) Does visceral adipose tissue exacerbate the association between age and brain network structure, 2) Does estradiol mitigate the negative association between VAT and brain network structure, and 3) What does this imply for healthy cognitive aging in men and women?  (more…)
Author Interviews, CDC, JAMA, Nutrition, Pediatrics, Weight Research / 24.06.2019

MedicalResearch.com Interview with: Liping Pan, MD, MPH Epidemiologist Division of Nutrition, Physical Activity, and Obesity National Center for Chronic Disease Prevention and Health Promotion Centers for Disease Control and Prevention MedicalResearch.com: What is the background for this study? Response: Children with severe obesity face significant health and social challenges. Children with obesity are at higher risk for having other chronic health conditions and diseases, such as asthma, sleep apnea, bone and joint problems, and type 2 diabetes. They also have more risk factors for heart disease such as high blood pressure, impaired glucose tolerance, and high cholesterol than their healthyweight peers. Children with obesity can be bullied and teased more than their healthyweight peers. They are also more likely to suffer from social isolation, depression, and lower self-esteem. Children with obesity are also more likely to have obesity as adults. This can lead to lifelong physical and mental health problems. Adult obesity is associated with a higher risk of type 2 diabetes, heart disease, and many types of cancers.  Childhood obesity is more common among children from lower-income families, as many lack access to healthy, affordable foods and beverages and opportunities for low-cost physical activity. (more…)
Author Interviews, OBGYNE, Pediatrics, PLoS, Weight Research / 16.06.2019

MedicalResearch.com Interview with: Henry J. Nuss, Ph.D. Assistant Professor Louisiana State University Health Sciences Center School of Public Health New Orleans, LA  MedicalResearch.com: What is the background for this study? Response: Childhood obesity rates in the U.S. have been increasing within the past 30 years. We can point to things like sedentary lifestyle, energy-dense, nutrient-poor foods and savvy marketing techniques of large food corporations that target kids and their parents to buy food items that aren’t healthy. That said, we do know that women who have an unhealthy weight status (as measured by BMI ≥ 25) tend to have offspring that eventually attain an unhealthy weight status themselves. Aside from environmental factors, could this be due to maternal programming or perhaps something in the breastmilk? Or both? We saw some interesting research that showed breastfed infants/toddlers born to asthmatic moms were more likely to develop asthma. Furthermore, this association became stronger the longer the infants/toddlers were breastfed. The conclusion here is that it must be something in the breastmilk. We knew that asthma and obesity are both inflammatory in nature and that there are specific pro- and anti-inflammatory and obesogenic bioactive compounds in human breastmilk. Some have been studied before but there were no studies at the time that tied all of the pieces together. If we could target specific compounds in the milk that were associated with unhealthy growth patterns in infants then we could perhaps be more specific in how we fight this problem. (more…)
Author Interviews, Environmental Risks, JAMA, Weight Research / 12.06.2019

MedicalResearch.com Interview with: Lead author: Yong-Moon (“Mark”) Park, MD, PhD Postdoctoral fellow Epidemiology Branch National Institute of Environmental Health Sciences   Senior author: Dale P. Sandler, PhD Chief, Epidemiology Branch, National Institute of Environmental Health Sciences National Institutes of Health MedicalResearch.com: What is the background for this study?   Response: A few studies had suggested that exposure to artificial light while sleeping was associated with obesity. However, the previous studies were cross-sectional, so we really do not know which came first - exposure to artificial light while sleeping or obesity. Another problem was that previous studies did not fully account for other characteristics that could affect this association, such as sleep duration and quality, calorie intake and dietary patterns, and physical activity. We studied nearly 44,000 women ages 35-74 from across the US who are enrolled in the Sister Study cohort. Women had body weight characteristics measured at baseline and provided self-reported information on weight at baseline and follow-up – on average 5.7 years later. (more…)
Author Interviews, Diabetes, Weight Research / 11.06.2019

MedicalResearch.com Interview with: Kalypso Karastergiou, MD, PhD Assistant Professor, Medicine, Endocrinology, Diabetes and Bone Disease Diabetes, Obesity and Metabolism Institute Icahn School of Medicine at Mount Sinai  MedicalResearch.com: What is the background for this study?   Response: Multiple studies, epidemiological as well as clinical, have established that body shape is an important and independent predictor of cardiovascular and metabolic disease risk and ultimately total mortality. Subjects that preferentially store weight in the abdominal area (often described as android, upper-body or apple-shape obesity) are at increased risk, whereas those who preferentially store weight in the lower body, in the gluteofemoral area (gynoid, lower-body or pear-shape), appear to be protected. The former is more common in men, whereas the latter in women, especially premenopausal women. The overarching questions in the field are:
  • What factors determine body shape?
  • Why are subjects with lower-body shape protected?
  • Can we exploit the physiological and pathophysiological mechanisms involved to improve stratification, prevention or treatment of obesity and related diseases? 
(more…)
Author Interviews, Brigham & Women's - Harvard, Prostate Cancer, Weight Research / 10.06.2019

MedicalResearch.com Interview with: Barbra Dickerman, PhD Research Fellow Department of Epidemiology Harvard T.H. Chan School of Public Health Boston, MA MedicalResearch.com: What is the background for this study? Response: Obesity is associated with a higher risk of advanced prostate cancer and poorer prognosis after diagnosis. However, emerging evidence suggests that the specific distribution of body fat may be an important prognostic factor for prostate cancer outcomes. In this original investigation, we analyzed body fat distribution on computed tomography imaging and the risk of being diagnosed with, and dying from, prostate cancer. This study was conducted among 1,832 Icelandic men with over a decade of follow-up in the Age, Gene/Environment Susceptibility-Reykjavik Study. (more…)
Author Interviews, Exercise - Fitness, Lifestyle & Health, Weight Research / 16.05.2019

MedicalResearch.com Interview with: sneakers-walkingFrancesco Zaccardi, MD, PhD Clinical Epidemiologist Assistant Director Leicester Real World Evidence Unit Leicester Diabetes Centre UK MedicalResearch.com: What is the background for this study? Response: The role of excess body weight on mortality has been extensively investigated during the last decades. Studies from several countries have also shown, however, that the risk of death in persons who are overweight or obese is lower if their fitness, a parameter indicating cardio-pulmonary health, is higher. Most of these studies reported the beneficial effect of fitness in terms of relative risk reduction, for example 20% reduction of risk of death. Relative estimates, though, are difficult to interpret. (more…)
Author Interviews, JAMA, OBGYNE, Weight Research / 09.05.2019

MedicalResearch.com Interview with: Dr-Romy GaillardRomy Gaillard MD PhD LifeCycle Project-Maternal Obesity and Childhood Outcomes Study Group Erasmus MC MedicalResearch.com: What is the background for this study?   Response: Obesity among women of reproductive age is a major problem for society. Scientists have long known that maternal weight before and during pregnancy are associated with pregnancy outcomes. Gestational weight gain is necessary to ensure healthy development of the fetus, but too much weight gain is associated with a higher risk of pregnancy complications. The magnitude of the associations of maternal weight before and during pregnancy with the risks of pregnancy complications, as well as the optimal amount of weight that especially obese women should gain during pregnancy were not well-known. (more…)
Author Interviews, Dermatology, Weight Research / 01.05.2019

MedicalResearch.com Interview with: Igor Snast, MD Department of Dermatology Rabin Medical Center–Beilinson Hospita Israel.  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Acne is the most common skin disorder among adolescents. Obesity has been suggested to promote acne, however various studies evaluating the relationship between obesity and acne have yielded contradictory outcomes. Our population-based study demonstrates that overweight, obese and severely obese youths have decreased odds of having acne (20%, 35% and 50% respectively) compared to normal-weight subjects. (more…)
Author Interviews, Nutrition, Weight Research / 28.04.2019

MedicalResearch.com Interview with: Dale Morrison, PhD School of Exercise and Nutrition Sciences Institute for Physical Activity and Nutrition MedicalResearch.com: What is the background for this study? What are the main findings?  Response: The study was conducted using a model of overfeeding that is likely to be representative of a typical Western overeating diet, high in both carbohydrates and fats; as opposed to a predominantly high-fat diet model that is commonly used in the literature. Our purpose was to examine which tissues are impaired first in response to overeating with a normal dietary composition. We initially hypothesized, based on earlier studies, that the liver would be impaired first by short-term overeating and then skeletal muscle (which soaks up much of the glucose following a meal) would be impaired much later with chronic overeating. However, we didn’t find this. The study found that the body copes with short periods of overeating with additional carbohydrates and makes adjustments by shifting metabolism towards utilizing these excess carbohydrates.  (more…)
Author Interviews, Brigham & Women's - Harvard, JAMA, Pediatrics, Weight Research / 26.04.2019

MedicalResearch.com Interview with: Vincent W. V. Jaddoe, MD, PhD Adjunct Professor of Epidemiology Department of Epidemiology MedicalResearch.com: What is the background for this study? What are the main findings?  Response: Childhood body fat may be affected by patterns of fetal and infant weight change. Children born small for gestational age (SGA) tend to have infant growth acceleration, whereas those born large for gestational age (LGA) tend to have infant growth deceleration. Little is known about fetal and infant growth patterns affecting visceral, liver, and pericardial fat, which are strongly associated with cardiometabolic disease in later life. We assessed in a large population cohort study whether fetal and infant weight change was associated with not only general, but also organ fat at school age. We observed that fetal and infant weight change patterns were both associated with childhood body fat, but weight change patterns in infancy tended to have larger effects. Fetal growth restriction followed by infant growth acceleration was associated with increased visceral and liver fat.  (more…)
Author Interviews, Cannabis, Psychological Science, Social Issues, Weight Research / 24.04.2019

MedicalResearch.com Interview with: "Chocolate Brownies" by Kurtis Garbutt is licensed under CC BY 2.0. To view a copy of this license, visit: https://creativecommons.org/licenses/by/2.0Jessica S. Kruger PhD Clinical Assistant Professor Department of Community Health and Health Behavior School of Public Health and Health Professions University of Buffalo Daniel J. Kruger PhD Adjunct Faculty Associate, Population Studies Center. Michigan's Population Studies Center  MedicalResearch.com: What is the background for this study? Response: The legal environment for cannabis is changing rapidly and an increasing proportion of people are using cannabis for medical and recreational purposes. All policy and practice should be informed by science, yet there is a large gap between evidence and existing practices, and the current scope of research on cannabis users is limited. Public Health has the responsibility of protecting the public, maximizing benefits and minimizing harm in any area. However, the Public Health approach to cannabis has largely been limited to a focus on abstinence, and Federal regulations have restricted the scope of cannabis-related research. (more…)
Author Interviews, Pediatrics, Weight Research / 23.04.2019

MedicalResearch.com Interview with: M. Pia Chaparro, MS, PhD Assistant Professor Department of Global Community Health and Behavioral Sciences School of Public Health and Tropical Medicine Tulane University New Orleans, LA 70112 MedicalResearch.com: What is the background for this study? What are the main findings? Response: In 2009, the WIC program changed the food packages participants receive to better align them with federal dietary guidelines. These changes included the addition of fruits, vegetables, and whole grains; a reduction in the amount of dairy and juice; and a calibration in formula amounts to match infants’ age and needs. We found that this change in the food package was associated with a 10-12% lower obesity risk at age 4 years among children who participated in WIC in Los Angeles County continuously from birth until age 4. (more…)
Author Interviews, Diabetes, Weight Research / 23.04.2019

MedicalResearch.com Interview with: Kishore M. Gadde, MD, Professor Fairfax Foster Bailey Endowed Chair in Heart Disease Prevention Medical Director, Clinical Services Pennington Biomedical Research Centre Baton Rouge, LA 70808  MedicalResearch.com: What is the background for this study? Response: Around 20 years ago, the Diabetes Prevention Program, DPP, enrolled 3,234 adults with excess body weight and impaired glucose tolerance. The idea was to compare the efficacy of either an intensive lifestyle intervention or metformin relative to placebo in preventing diabetes. Over approximately 3 years, both lifestyle and metformin were effective, but lifestyle intervention was better for weight loss as well as in reducing the risk of diabetes. After the blinded treatment phase ended, the researchers continued to follow this cohort in their originally randomised groups.  (more…)
Author Interviews, Dermatology, Weight Research / 15.04.2019

MedicalResearch.com Interview with: Igor Snast, MD Department of Dermatology Rabin Medical Center–Beilinson Hospital Israel MedicalResearch.com: What is the background for this study? What are the main findings? Response: Acne is the most common skin disorder among adolescents. Obesity has been suggested to promote acne, however various studies evaluating the relationship between obesity and acne have yielded contradictory outcomes. Our population-based study demonstrates that overweight, obese and severely obese youths have decreased odds of having acne (20%, 35% and 50% respectively) compared to normal-weight subjects. (more…)
Author Interviews, Lancet, OBGYNE, Pediatrics, Weight Research / 28.03.2019

MedicalResearch.com Interview with: Liv Guro Engen Hanem, PhD Candidate Department of Clinical and Molecular Medicine Norwegian University of Science and Technology MedicalResearch.com: What is the background for this study?   Response: The antidiabetic drug metformin is increasingly used in pregnancy: to treat gestational diabetes and type 2 diabetes, and to prevent pregnancy complications related to polycystic ovary syndrome (PCOS) and obesity. Metformin passes the placenta, and the fetus is thus exposed to the drug. Although no teratogenicity has been reported, metformin might have long-term effects on offspring health. This study is a follow-up of cardiometabolic risk factors of 141 5- to 10-year-old children born in the PregMet study. This study was a double-blind, randomized controlled trial (RCT) designed to test the hypothesis that metformin given throughout pregnancy reduces the prevalence of pregnancy complications that are associated with the common endocrine disorder PCOS. Pregnant women with PCOS were randomized to receive metformin or placebo throughout pregnancy.  (more…)
Author Interviews, Endocrinology, Weight Research / 27.03.2019

MedicalResearch.com Interview with: Liya Kerem, MD Fellow, Pediatric Endocrine Unit Massachusetts General Hospital for Children Harvard Medical School MedicalResearch.com: What is the background for this study?   Response: The hypothalamic neurohormone Oxytocin (OXT), shown to decrease food intake in animals and humans, is a promising novel treatment for obesity. We previously showed that in men with overweight/obesity, intranasal (IN)OXT reduced the fMRI activation in the ventral tegmental area (VTA), the origin of the mesolimbic dopaminergic reward system, in response to high-calorie food vs non-food visual stimuli. Here, we employed fMRI functional connectivity analysis, which better characterizes the exchange in information between neural systems in a context-dependent manner. We hypothesized that Oxytocin would reduce the functional connectivity of the VTA with food motivation brain areas in response to high-calorie foods.  (more…)
Author Interviews, Duke, Endocrinology, Environmental Risks, Thyroid Disease, Weight Research / 27.03.2019

MedicalResearch.com Interview with: Christopher D. Kassotis, Ph.D. NRSA Postdoctoral Research Scholar Stapleton Lab Duke University Nicholas School of the Environment Durham, NC 27708  MedicalResearch.com: What is the background for this study? What are the main findings?
  • So this was something that Heather Stapleton had been curious about for years, as she's been one of several researchers characterizing the hundreds of chemicals that have been measured in indoor house dust. Before I came to Duke, one of her PhD students had measured the ability of many common indoor contaminants to activate the peroxisome proliferator activated receptor gamma (PPARg). The majority of these chemicals did, often quite well, which led to them testing indoor house dust extracts, also finding that the majority of dust extracts were also able to do so at very low levels. As PPARg is often considered the master regulator of fat cell development, the next obvious question was whether these common contaminants (and house dust) could promote fat cell development in cell models. My first work at Duke evaluated a suite of common indoor contaminants, finding that many of these chemicals could promote fat cell development, and that low levels of house dust extracts did as well.
  • We next explored this more systematically in a group of adults involved in a thyroid cancer cohort (this was just recently published in Science of the Total Environment: https://www.sciencedirect.com/science/article/pii/S0048969719307715?dgcid=author
  • In this study we evaluated the extent to which house dust extracts could promote fat cell development in a common cell model, and associated this with the metabolic health of adults living in these homes. We found that the greater extent of fat cell development was associated with significantly greater thyroid stimulating hormone concentrations (control residents only, with no evidence of thyroid dysfunction) and lower free triiodothyronine (T3) and thyroxine (T4). We further found a significant and positive association between extent of fat cell development and the body mass index (BMI) of all adults in the study. So this suggested that the indoor environment might play a role in the BMI and metabolic health of residents, and we next wondered if this would be more pronounced in children, who may be exposed to these contaminants during a critical window of development.
  • The next step, for our current work, was to substantiate these effects in a larger group of households, each with children.
  • Our major conclusions thus far have been that ~80% of house dust extracts promote significant fat cell development in a cell model - either via development from precursor cells into mature fat cells, measured via accumulation of lipids into the cells, or via the proliferation of those precursor fat cells. We also reported positive correlations of fat cell development with the concentrations of 70 different contaminants in the dust from these homes, suggesting that mixtures of contaminants are likely all acting weakly to produce these effects in combination. We’ve also begun to assess the other chemicals present in dust - chemistry can be either targeted (measuring concentrations of specific known chemicals in a sample), or non-targeted, where you try and determine the identity of the other chemicals in a sample. This has greater utility for identifying many more chemicals, though you will often not get chemical concentrations from this, nor absolute confirmed identification - just varying degrees of certainty based on evidence. Thus far we report approximately 35,000 chemicals in house dust samples across this study, and differential analyses have begun to pick out the few (less than 10 in each case) chemicals most differentially expressed between samples that exhibit high degrees of fat cell development in the lab vs inactive samples, for example, or which are differentially present in the homes of children categorized as obese or overweight. We are now working to confirm identity of these select contaminants that are more likely to be causative factors in the results we have observed.
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