High prevalence of overweight and obesity in adults with Crohn's disease: associations with disease and lifestyle factors.

peer-reviewedObesity and overweight are major public health issues. Although traditionally associated with weight loss, there is now evidence that increasing Body Mass Index (BMI) and overweight are emerging features of Crohn's disease (CD) and may be associated with more severe disease course. The aim of the study was to determine the prevalence of overweight and obesity in patients with CD compared with matched healthy controls and to identify disease-specific and generic factors associated with current BMI in this group.PUBLISHEDpeer-reviewe

High prevalence of overweight and obesity in adults with Crohn\u27s disease: associations with disease and lifestyle factors.

Obesity and overweight are major public health issues. Although traditionally associated with weight loss, there is now evidence that increasing Body Mass Index (BMI) and overweight are emerging features of Crohn\u27s disease (CD) and may be associated with more severe disease course. The aim of the study was to determine the prevalence of overweight and obesity in patients with CD compared with matched healthy controls and to identify disease-specific and generic factors associated with current BMI in this group.PUBLISHEDpeer-reviewe

High-Content Screening Assay for Identification of Chemicals Impacting Cardiovascular Function in Zebrafish Embryos

Targeted assays are needed to better evaluate effects of chemicals on organogenesis and begin classification of chemicals by toxicologically relevant modes-of-action. Using transgenic zebrafish (<i>fli1:egfp</i>) that stably express eGFP within vascular endothelial cells, we have developed and optimized a 384-well-based high-content screening (HCS) assay that enables us to screen and identify chemicals affecting cardiovascular function at sublethal, nonteratogenic concentrations. Following static exposure of one embryo per well from 5 to 72 h postfertilization (hpf), automated image acquisition procedures and custom image analysis protocols are used to quantify body length, circulation, heart rate, pericardial area (a biomarker for cardiac looping defects), and intersegmental vessel area within freshly hatched live embryos. After optimizing 72 hpf anesthetization procedures, we evaluated each end point across four independent control plates containing 384 initial embryos per plate. Survival and imaging success rates across these plates ranged from 93 to 99% and 42 to 74%, respectively. Criteria were then defined for assay success and analysis of treatments, and 10 chemicals were screened for targeted effects on cardiovascular function. Compared to existing zebrafish-based assays, this method provides a comprehensive discovery platform with (1) increased sample sizes; (2) broad concentration–response format; and (3) the ability to identify chemicals that target cardiovascular function at nonteratogenic concentrations

Leveraging Embryonic Zebrafish To Prioritize ToxCast Testing

On the basis of two pilot high-content screens of ToxCast Phase I chemicals, we previously demonstrated that exposure of zebrafish embryos to abamectin and butafenacil abolished spontaneous activity and induced severe anemia, respectively. Therefore, the objective of this study was (1) to determine whether high-throughput <i>in vitro</i> screening data from the ToxCast program would have prioritized abamectin and butafenacil for further testing and (2) to determine whether a single three-day zebrafish embryo assay is a strong predictor of Toxicological Priority Index (ToxPi) scores derived from ToxCast data. Using publically available ToxCast assay end point data and target information, we calculated assay hit rates, developed hazard classifications, and relied on the ToxPi Graphical User Interface to generate ToxPi charts and scores within a biological process-driven configuration. Overall, our findings suggest that embryonic zebrafish may be valuable for prioritizing ToxCast testing as well as addressing toxicity pathways that may not be represented by the ToxCast assay battery

High-Content Screening Assay for Identification of Chemicals Impacting Spontaneous Activity in Zebrafish Embryos

Although cell-based assays exist, rapid and cost-efficient high-content screening (HCS) assays within intact organisms are needed to support prioritization for developmental neurotoxicity testing in rodents. During zebrafish embryogenesis, spontaneous tail contractions occur from late-segmentation (∼19 h postfertilization, hpf) through early pharyngula (∼29 hpf) and represent the first sign of locomotion. Using transgenic zebrafish (<i>fli1:egfp</i>) that stably express eGFP beginning at ∼14 hpf, we have developed and optimized a 384-well-based HCS assay that quantifies spontaneous activity within single zebrafish embryos after exposure to test chemicals in a concentration–response format. Following static exposure of one embryo per well from 5 to 25 hpf, automated image acquisition procedures and custom analysis protocols were used to quantify total body area and spontaneous activity in live embryos. Survival and imaging success rates across control plates ranged from 87.5 to 100% and 93.3–100%, respectively. Using our optimized procedures, we screened 16 chemicals within the US EPA’s ToxCast Phase-I library, and found that exposure to abamectin and emamectin benzoateboth potent avermectinsabolished spontaneous activity in the absence of gross malformations. Overall, compared to existing locomotion-based zebrafish assays conducted later in development, this method provides a simpler discovery platform for identifying potential developmental neurotoxicants

High-content screening in zebrafish embryos identifies butafenacil as a potent inducer of anemia.

Using transgenic zebrafish (fli1:egfp) that stably express enhanced green fluorescent protein (eGFP) within vascular endothelial cells, we recently developed and optimized a 384-well high-content screening (HCS) assay that enables us to screen and identify chemicals affecting cardiovascular development and function at non-teratogenic concentrations. Within this assay, automated image acquisition procedures and custom image analysis protocols are used to quantify body length, heart rate, circulation, pericardial area, and intersegmental vessel area within individual live embryos exposed from 5 to 72 hours post-fertilization. After ranking developmental toxicity data generated from the U.S. Environmental Protection Agency's (EPA's) zebrafish teratogenesis assay, we screened 26 of the most acutely toxic chemicals within EPA's ToxCast Phase-I library in concentration-response format (0.05-50 µM) using this HCS assay. Based on this screen, we identified butafenacil as a potent inducer of anemia, as exposure from 0.39 to 3.125 µM butafenacil completely abolished arterial circulation in the absence of effects on all other endpoints evaluated. Butafenacil is an herbicide that inhibits protoporphyrinogen oxidase (PPO)--an enzyme necessary for heme production in vertebrates. Using o-dianisidine staining, we then revealed that severe butafenacil-induced anemia in zebrafish was due to a complete loss of hemoglobin following exposure during early development. Therefore, six additional PPO inhibitors within the ToxCast Phase-I library were screened to determine whether anemia represents a common adverse outcome for these herbicides. Embryonic exposure to only one of these PPO inhibitors--flumioxazin--resulted in a similar phenotype as butafenacil, albeit not as severe as butafenacil. Overall, this study highlights the potential utility of this assay for (1) screening chemicals for cardiovascular toxicity and (2) prioritizing chemicals for future hypothesis-driven and mechanism-focused investigations within zebrafish and mammalian models

High prevalence of overweight and obesity in adults with Crohn's disease: associations with disease and lifestyle factors.

Obesity and overweight are major public health issues. Although traditionally associated with weight loss, there is now evidence that increasing Body Mass Index (BMI) and overweight are emerging features of Crohn's disease (CD) and may be associated with more severe disease course. The aim of the study was to determine the prevalence of overweight and obesity in patients with CD compared with matched healthy controls and to identify disease-specific and generic factors associated with current BMI in this group