bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of exercise during the menopausal transition on circulating inflammatory markers, including plasma zinc
Authors: Woodhouse Leslie Ruth , Burtt Benjamin , Domek Joseph , Gustafson Mary , Keim Nancy L. , Campbell Caitlin , Peerson Jan
Published: June 2021

The US Dietary Guidelines (DG) recommends 60 min of moderate to vigorous intensity activity most days of the week to help manage body weight and prevent gradual, unhealthy weight gain. Chronic exercise can improve markers of systemic low‐grade inflammation. Healthy, peri‐menopausal, sedentary women (42–52y, BMI 18–32) were assigned to a control (CON, n=10) or exercise (EXE, n=18) regimen for a 6 mo study. The EXE intervention was a combined aerobic and resistance workout 6 d/wk, 60 min/d. Body weight and composition were determined at mo 0, 3 & 6. Fasting levels of insulin, pro‐inflammatory markers (IM: IL1‐ß, IL‐6, IL‐8, TNF‐α, hsCRP) and Zn were measured at mo 0, 1, 3 & 6. Baseline IM were elevated in women with BMI>;25.0 vs. BMI<25.0. The EXE group had a significant decline in body weight at mo 6 (1.2 kg), with a significant decrease in fat mass (primarily android) and increase in lean body mass by mo 3. Controlling for baseline values, the EXE group had an improved insulin sensitivity index and decreased IL‐6 by mo 3. Positive correlations were observed between the changes in CRP & BMI; IL‐8 & IL1‐ß, TNF‐α and Zn; IL1‐ß & Zn; and negative correlations with bone mineral density & IL‐8 and TNF‐α. The decrease in IM in women with BMI>;25.0 was more pronounced than in women with BMI<25.0. Following the USDG for activity will result in health improvements in peri‐menopausal women as determined by body composition and IM. USDA, ARS, WHNRC
Environmental enrichment and cafeteria diet synergistically modify the response to chronic variable stress in rats
Authors: Zeeni Nadine , Bassil Maya , Al Nafeesi Shoug , Ibrahim Mariana , Zein Tala , Fromentin Gilles , Chaumontet Catherine , Daher Costantine
Published: June 2021

Evidence shows that exposure to environmental enrichment (EE) or to a highly palatable diet can reduce the response to chronic stress in rats. To further explore the relationships between EE, dietary intake and stress, male Sprague‐Dawley rats were fed one of two diets for 5 weeks: high carbohydrate (HC) or “Cafeteria” (CAF) (offering a choice of highly palatable cafeteria food). Also, they were housed in cages with or without EE. After the first two weeks, half of the animals from each group were stressed daily using a chronic variable stress (CVS) paradigm, while the other half were kept undisturbed until the end of the experiment. The effects of stress, EE and diet on animal adiposity, serum lipids, and stress hormones were analyzed. Results showed increases in liver weight and intra‐abdominal fat associated with the CAF diet and an increase in bodyweight gain associated with both the CAF diet and EE. Stressed animals showed increased serum corticosterone (CORT) levels compared to non‐stressed animals (P<0.001). In addition, there was a significant interaction between diet and EE (P=0.02) on serum CORT levels: the CVS‐induced increase in CORT was attenuated in the presence of EE and the CAF diet independently and in a synergistic manner. Our study thus provides evidence that the availability of a positive rearing environment combined with highly palatable food renders rats more resilient to the effects of CVS.
THE RESPONSE TO VITAMIN E SUPPLEMENTATION
Authors: Guertin KA , Agler AH , LaBarre J , Parker RS , Kristal AR , Arnold KB , Hartline J , Goodman PJ , Tangen CM , Minasian LM , Lippman SM , Klein E , Cassano PA
Published: June 2021

Background

Vitamin E has antioxidant properties, which may promote some health outcomes. Plasma vitamin E levels vary widely, and more so among supplement users, however little is known about individual characteristics that affect the degree to which plasma concentrations increase with supplementation.

Methods

We investigated the association between participant characteristics and change in plasma concentration in response to vitamin E supplementation (400 mg/day all rac α‐tocopheryl acetate) over three years in participants of the Respiratory Ancillary Study (RAS) to the Selenium and Vitamin E Cancer Prevention Trial (SELECT).

Results

African American men had lower baseline plasma α‐tocopherol concentration, and had a 50% lower increase in concentration in response to supplementation in comparison to others (p<0.0001), independent of cholesterol and other covariates.

Conclusions

Future studies should consider the magnitude of the change in plasma concentration in relation to the effects of supplementation. The lower response in African Americans may indicate less possible benefit, or may indicate metabolic consumption of the supplemented nutrient, thus more benefit.

Grant Funding Source: NIH RO1HL071022, NCI/DCPCA37429, NCCAM
Progress in the Development of Federal Resources to Assess Dietary Supplement (DS) Exposures
Authors: Dwyer Johanna , Andrews Karen W , Bailey Regan L , Betz Joseph M , Burt Vicki L , Costello Rebecca B , Emenaker Nancy J , Gahche Jaime J , Hardy Constance J , Pehrsson Pamela R , Roseland Janet M , Saldanha Leila G
Published: June 2021

Accurate total exposure estimates are necessary to examine the role of nutrients and bioactives with health outcomes, as well as to monitor safety.

Objective

Review progress in the development of methods and databases to assess exposures from DS.

Method

Stakeholder meetings and workshops; and an ad hoc Federal Working Group suggest and guide product development.

Results

DS intakes have been added to the NHANES 24‐hr recall questionnaire. An analytically validated DS composition database (DS Ingredient Database) is publicly available through the NLM web portal, which contains adult and child multi‐vitamin and mineral (MVM) DS and calculators to compare declared label with estimated analytical values. OTC prenatal MVM and omega‐3 supplements are now being added. A DS Label Database is under development, with full label information from virtually all DS products offered for sale in the US, and links to a structured vocabulary for indexing DS. A MyDS app lets consumers’ record products they take.

Conclusion

These resources will help researchers accurately assess exposure to nutrients and bioactives from DS. Funding: Office of Dietary Supplements, National Institutes of Health
The contribution of gastroenteropancreatic appetite hormones to protein‐induced satiety
Authors: Astrup Arne , Belza Anita , Ritz Christian , Sørensen Mejse Q , Holst Jens J , Rehfeld Jens F
Published: June 2021

We studied the hormonal mediation of the satiating effect of protein by a randomized, double‐blind, crossover meal‐test study testing three similar meals with varying protein content. Twentyfive men (BMI: 25.9 kg/m2) were exposed to isocaloric meals with fixed 30E% fat and protein adjusted at the expense of carbohydrate: normal (NP) = 14 E%; medium‐high (MHP) = 25 E% (MHP); high (HP) = 50 E% protein. Protein increased satiety and fullness dose‐dependently compared to NP: 7 and 6% greater for MHP, 16 and 19% greater for HP (P<0.001) respectively. Protein also increased GLP‐1 dose‐dependently: 10% for MHP (3.4±2.4, P=0.02), 20% for HP (6.9±2.4, P<0.0001); PYY by 7% for MHP (P=0.0002) and by 14% for HP (P<0.0001). Glucagon was increased by 47% (P<0.0001) for MHP and by 116% (P<0.0001) for HP. HP increased insulin and CCK, and decreased ghrelin and GIP, compared to NP (P<0.05). There was an interaction between GLP‐1 and PYY 3–36 (P=0.03) as a determinant of satiety, besides the additive effect of GLP‐1 (P=0.006) on composite appetite score. We conclude that protein dose‐dependently increases satiety and that postprandial changes in circulating GLP‐1, PYY and glucagon are partly responsible for the appetite suppressant effect of protein.

Supported by grant from Danish Agricultural and Food Council
Interactions between Francisella tularensis and Hepatocytes
Authors: Thomas Cindy A. , Furie Martha
Published: June 2021

Francisella tularensis is a facultative intracellular bacterium and the etiological agent of tularemia. This pathogen is classified as a category A agent of bioterrorism. Regardless of the route of transmission, the liver is an important target of infection in tularemia, and F. tularensis grows to high numbers within hepatocytes, the major cell type of this organ. This study investigates the mechanisms that influence the uptake and replication of F. tularensis in hepatocytes. The study was performed with F. tularensis Live Vaccine Strain (LVS) and the highly virulent Schu S4 strain, the murine AML‐12 and human HH4 hepatocytic cell lines, and primary mouse hepatocytes. We observed that both heat‐killed and formalin‐fixed bacteria were readily ingested by the hepatocytes. Treatment of the bacteria with chloramphenicol also had no effect on uptake. Primary hepatocytes were less efficient at taking up bacteria compared with the cell lines. Notably, the Schu S4 grew more extensively than the LVS in primary hepatocytes. We have generated a collection of transposon mutants of the LVS and are screening it to identify bacterial factors needed for uptake and replication in hepatocytes. In summary, our results show that uptake of the LVS by hepatocytes is a passive process on the part of the bacterium. Furthermore, the ability of this organism to replicate in hepatocytes may be linked to virulence. NIAID T32 A1007539, P01 AI055621
Identification of unitary tight junction pore opening/closing events in MDCK monolayers
Authors: Weber Christopher R , Liang Guo Hua , Shen Le , Wang Yitang , Nelson Deborah J , Yu Alan S , Turner Jerrold R
Published: June 2021

Analyses of epithelial barrier function have led to the hypothesis that tight junctions are populated by claudin‐dependent pores that define paracellular ion conductance and charge selectivity. Consistent with this claudin‐2 expression increases paracellular Na+ permeability of MDCK I monolayers. However, available measures cannot resolve function of individual pores. To overcome this limitation, we have used patch clamp techniques to define local tight junction function. Local tight junction recordings reveal transient 63±8 pS openings (0.004±0.001 Hz). Claudin‐2 expression reduces global TER by a 71±1% and increases the frequency of individual openings to 0.023±0.007 Hz without changing their size (57±3 pS). Ion substitution analyses demonstrate that the openings are selective for cations (PNa/PCl = 4.9 ± 0.9) with radii <2.8Å. Global analyses suggest that flux across claudin‐2I66C pores is blocked by cysteine derivatization. Consistent with this, while claudin‐2I66C expression had effects similar to claudin‐2 expression, openings in MDCK I expressing claudin‐2I66C were acutely terminated upon cysteine derivatization. These data show that claudin‐2 creates local, transient tight junction flux events that define global epithelial barrier function. We suggest that opening and closing of paracellular claudin pores forms the molecular basis of tight junction size and charge selectivity.
Effects of prototypical nuclear receptor ligands on the expression of enzymes and transporters in primary human hepatocytes
Authors: Ullrich Anett , Keiser Markus , Sauer Anne , Runge Dieter , Siegmund Werner , Oswald Stefan
Published: June 2021

Carbamazepin (Carb), efavirenz (Efa), and rifampicin (Rifa) are known to cause substantial drug‐drug interactions by induction of metabolizing enzymes and transporter proteins via activation of pregnane × and/or constitutive androstane nuclear receptors (PXR and CAR). In order to provide a comprehensive overview about the complex induction pattern of hepatic metabolizing enzymes and transporter proteins, we investigated the effects of the aforementioned substances in primary human hepatocytes.

Whole‐transcript arrays with isolated mRNA from hepatocytes were performed with an Affimetrix GeneChip® after incubation with 0.1% DMSO (control), 10 μM Efa or Rifa or 250 μM Carb, respectively. Expression of 42 regulated genes of metabolism and transport were measured using a TaqMan® low density array.

All compounds demonstrated inductive effects on the metabolizing enzymes CYP2B6, CYP2C8, CYP3A4, CYP3A5 and CYP3A7 but showed suppressive effects on CYP2E1. ABCB1 and ABCB4 were induced by Efa and ABCC5 and SLC47A1 by Carb. ABCC2, ABCC4 and ABCG2 were induced by both substances. The expression of ATP dependent efflux transporters with the exception of ABCB11 were increased after incubation with all tested drugs.

Carb, Efa and Rifa showed strong effects on the expression of several metabolizing enzymes and drug transporters which might be the reason for clinically observed drug‐drug interactions.
The Five Most Common Misconceptions of Students Embarking on a Job Search
Authors: Wendlandt Nancy
Published: June 2021

Sooner or later the time will come for everyone to leave the life of a student behind and embark on a career. Regardless of whether your terminal degree is a B.A., B.S., M.S., Ph.D., etc. the basic parameters for finding that critical first “real” job are essentially the same, and persons with an “advanced” degree are prone to the same rookie mistakes and challenges as those seeking an entry level position immediately after college. Following the undergraduate poster session on Saturday afternoon, students and mentors are invited to a workshop on how to prepare for and navigate a successful job search. The format will be informal and focused upon addressing questions from the participants. The discussion will cover topics such as a) how to evaluate options and identify next steps, b) what employers look for in a candidate, c) tips for a more effective job search, d) how to prepare for interviews, e) what to expect in your first job, and f) other questions the audience may have.
The Effect of Obesity and Development on In Vitro Hepatic Metabolism
Authors: Danielson Gina , Chiney Manoj , Tam Harrison , Johnson L'Aurelle
Published: June 2021

It is well established that oxidative enzyme activity differs between obese and healthy weight adults. This study examined the interaction between age and obesity using a rat model of obesity on the developmental profiles of intrinsic clearance of hepatic phase 1 enzyme activity. Liver microsomes were isolated from OLETF(obese)/LETO(lean) at various weeks of age. CYP 1A2, CYP 2E1, CYP 2D2, and xanthine oxidase (XO) enzyme activity was assessed using probe substrates. Both age and obesity effects were tested for significance (p‐value ¡Ü0.05). Age related differences were observed in all enzymes characterized (p<0.004) within both the lean and obese groups. Obese rats had a 25% greater total exposure to 1A2 activity when compared to the lean (p=0.017). Conversely, obese rats had 30% less total exposure to 2D2 activity when compared to the lean (p=0.0002). There were no statistical differences in total exposure for 2E1 or XO between the lean and obese groups p=0.082 and 0.060, respectively. The results indicate that alterations in enzymatic drug metabolism are dependent on both age and obesity status. The changes observed are unique to CYP 1A2 and CYP 2D2 and may provide further insight towards the impact of age and obesity on drug metabolism in humans. Research was supported by University of Minnesota College of Pharmacy.
The Role of FcRn in the Disposition, Metabolism and Pharmacokinetics of Soluble Non‐Crosslinking Immune Complexes
Authors: Alvarez Hamsell M. , So On‐Yee , Hsieh SuChun , Shinsky‐Bjorde Natalie , Ma Huiping , Song Yaoli , Pang Yinuo , Marian Melinda , Escandón Enrique
Published: June 2021

Human interleukin 10 (hIL‐10) is a potent cytokine homodimer that has been investigated in the clinic for inflammatory indications. We have characterized the effects of IL‐10 pegylation and formation of IL‐10/αIL‐10 immune complexes in the pharmacokinetics (PK), biodistribution and biotransformation of IL‐10 in mice. Plasma size exclusion analysis indicated that fluorolabeled native and pegylated murine IL‐10 are stable in the circulation without evidence of biotransformation. Pegylation of IL‐10 resulted in increased exposure, ~2.7‐fold increase in half‐life from 0.098 to 0.26 days and ~20‐fold reduction in clearance. Kidney is the major organ of disposition for both native and pegylated mIL‐10 with renal uptake directly related to systemic clearance. hIL‐10/αIL‐10 complexes were characterized in plasma without evidence of free or degraded hIL‐10 fragments. The hIL‐10 exposure in immune complexes vs. hIL‐10 alone, increased from 0.53 to 11.28 ug*day/ml, with a half‐life of 1.16 days and a ~23‐fold reduction in clearance. In contrast to free interleukin 10, antibody bound hIL‐10 was targeted mainly to the liver with minimal renal distribution. In vitro analysis of FcRn interactions shows a ~10‐fold reduction in binding affinity for the antibody when present as IL‐10/αIL‐10 immune complexes. The changes in FcRn binding and increased liver uptake of IL‐10/αIL‐10 immune complexes may explain in part the unique PK properties of soluble antibody‐bound IL‐10.
Vitamin D receptor activation enhances Benzo[a]pyrene metabolism via CYP1A1 expression in macrophages
Authors: Uno Shigeyuki , Matsunawa Manabu , Akagi Daisuke , Endo‐Umeda Kaori , Ikeda Kazumasa , Makishima Makoto
Published: June 2021

Benzo[a]pyrene (BaP) activates the aryl hydrocarbon (AHR) and induces the expression of xenobiotic metabolic genes, including cytochrome P450 (CYP) 1A1. CYP1A1 is involved not only in BaP detoxification but also in metabolic activation, which results in DNA adduct formation. Vitamin D receptor (VDR) also regulates expression of other xenobiotic metabolism genes, including CYP3A. We investigated the cross‐talk between AHR and VDR signaling pathways and found that 1α,25‐ dihydroxyvitamin D3 (1,25(OH)2D3) enhanced BaP‐induced transcription of CYP1A1 in human monocytic U937 cells and THP‐1 cells. 1,25(OH)2D3 alone did not induce CYP1A1 and 1,25(OH)2D3 plus BaP did not increase other CYP1 family (CYP1A2 or CYP1B1) mRNA expression in U937 cells. Combination of 1,25(OH)2D3 and BaP increased CYP1A1 protein levels, BaP hydroxylation activity and BaP‐DNA adduct formation in U937 cells and THP‐1 cells more effectively than BaP alone. The combined effect of 1,25(OH)2D3 and BaP on CYP1A1 mRNA expression in U937 cells and/or THP‐1 cells was inhibited by VDR knockdown and VDR or AHR antagonists. Electrophoretic mobility shift assays and chromatin immunoprecipitation assays showed that VDR directly bound to an everted repeat 8 motif in the human CYP1A1 promoter. Thus, induction of CYP1A1 by the activation of VDR and AHR may contribute to BaP‐mediated toxicity and the physiological function of this enzyme.
Improvement of cholinergic function during normal and pathological aging
Authors: Nagy Paul Michael , Aubert Isabelle
Published: June 2021

Cholinergic neurons produce the neurotransmitter acetylcholine and are essential to critical brain functions, including motor function, learning and memory. The vesicular acetylcholine transporter (VAChT) is expressed by cholinergic neurons and packages acetylcholine into vesicles to prepare its release to the synaptic cleft. Here, we report that increasing levels of VAChT is associated with neurochemical alterations that may improve motor behaviour and cognitive decline during normal and pathological aging. Using RT‐PCR, immunohistochemistry, and western blot, we show that B6.Cg‐Tg(RP23–268L19‐EGFP)2Mik/J mice exhibit enhanced VAChT mRNA and protein expression. These changes were sufficient to enhance acetylcholine release at cholinergic terminals, and elicit changes in behavioural functions including spontaneous and novelty‐induced activity and measures of cognition. Mechanisms for these behavioural features will be explored. Taken together, this study contributes to our fundamental understanding of cholinergic regulation, specifically in response to increased VAChT expression, and may implicate VAChT as a target to maintain adequate cholinergic function during aging.
Assessing the quality of dissection: A method for improving anatomy knowledge of first year medical students
Authors: Nwachukwu Chika , Lachman Nirusha , Pawlina Wojciech
Published: June 2021

Anatomy learned by active exploration in the dissection laboratory has been shown to be beneficial in improving anatomic knowledge, promoting self‐reflection, teamwork, and professionalism. Decreased dissection time may affect the quality of dissection and ultimately retention of gross anatomy knowledge. This could translate to lower student performance in the anatomy course. The purpose of this study was to determine whether evaluating the quality of students’ dissection has an effect on practical examinations performance, mid and end‐course evaluations. Quality of dissections for each team enrolled in a gross anatomy course at Mayo Medical School was evaluated bi‐weekly. Each member of the dissection team received the same score which was calculated towards 5% of their final grade. Dissections were evaluated using a five‐point rubric that incorporates measures for determining whether students had met laboratory learning objectives. Assessment of anatomic knowledge was based on laboratory practical exam scores recorded at intervals throughout the course and achievements on daily audience response system quizzes. Increase in quality of dissection was associated with improvement in practical exams. Teams that received lower dissection scores had lower scores on practical exams. Our results imply that students who achieve daily dissection goals, perform better on the practical examinations.

Grant Funding Source: Department of Anatomy
Embryonic origins of novelty and constraint in the amniote upper jaw
Authors: Young Nathan , Hu Diane , Lainoff Alexis , Hallgrímsson Benedikt , Marcucio Ralph
Published: June 2021

Mammals, birds, and reptiles exhibit remarkable diversity in the shape, size, and relative proportions of the upper jaw. Determining when these differences are generated is critical to our understanding of how developmental mechanisms impact evolutionary diversification. Here we demonstrate that all major amniote lineages share a common pattern of embryonic shape and growth up until fusion of the facial primordia. Subsequent to fusion, avian and non‐avian lineages diverge in Sonic hedgehog (SHH) signaling domain expression, leading to lineage‐specific alterations in facial proportions. As a result, the avian upper jaw is composed primarily of frontonasal derivatives, while in non‐avian amniotes the maxillary derivatives comprise the largest proportion of the jaw, in both cases regardless of overall snout length. Experimental manipulation of pre and post‐fusion SHH‐domains in avians phenocopies the proportions of non‐avian amniote upper jaws. This developmental sequence of early conservation followed by later diversification demonstrates that fusion of the facial primordia is a critical prerequisite to evolutionary divergence of the upper jaw, while regulation of SHH‐signaling mediated postfusion growth processes is an important mechanism by which evolutionary variation in jaw shape is generated.
Mycobacterium tuberculosis proteasomes, pupylation and pathogenesis
Authors: Darwin K Heran
Published: June 2021

Prokaryotic ubiquitin‐like protein, Pup, specifically conjugates to proteasome substrates in the human pathogen Mycobacterium tuberculosis (Mtb). Like ubiquitylation, pupylation occurs on lysines, but proceeds by a different chemistry. I will discuss recent developments in the characterization of the Pup pathway. The Pupproteasome system is essential for the pathogenesis of Mtb, thus a better understanding of this pathway will hopefully allow us to develop new drugs to treat one of the world's most devastating diseases.
Towards a comprehensive understanding of cellular metabolism
Authors: Rabinowitz Joshua , Xu Yifan , Clasquin Michelle F , Johnson Sarah , Lu Wenyun , Campagna Shawn R , Yakunin Alexander F , Caudy Amy A , Letisse Fabien
Published: June 2021

Metabolism is the best mapped major biochemical network. Nevertheless, even in model organisms like baker's yeast, important pathways continue to be discovered. One strategy for pathway discovery is to analyze, by untargeted LC‐MS, the metabolic consequences of knocking out genes of unknown function. This approach recently identified a new route of converting glycolytic intermediates into ribose, which yeast cells activate when demand for ribose exceeds that for NADPH. With the aim of further elucidating pathways involving ribose and NADPH metabolism, we are now investigating several other poorly annotated enzymes. Multiple enzymes contribute to a ribose salvage pathway, which catabolizes ribosomal RNA to generate energy during nutrient starvation. Others contribute to NADPH homeostasis. The functional roles of these enzymes and pathways in the context of energy and cofactor metabolism will be described.
Will this be on the test? Characterizing the cognitive levels of undergraduate biology courses
Authors: Momsen Jennifer , Montplaisir Lisa , Anderson Elizabeth
Published: June 2021

Undergraduates’ motivation to learn is complex, driven in part by course assessments and student expectations of those assessments. Using Bloom's Taxonomy, we characterized cognitive learning levels of biology assessments. We specifically ask (1) what cognitive skills are assessed in introductory and upper level biology courses and (2) how well aligned are introductory and upper level biology courses? Three independent raters coded over 3000 assessment items from introductory and advanced biology courses; agreement among raters was 83%. Assessments in introductory biology courses assessed primarily knowledge (57% of items) and comprehension (36% of items); upper level courses also assessed primarily knowledge and comprehension (75% and 18%, respectively), with a limited number of items assessing higher cognitive levels. These results may reinforce student‐held beliefs that biology is about memorizing facts. In the midst of transforming and reforming undergraduate biology education, revisiting how we assess students’ learning is critical for scaffolding the development of students’ cognitive abilities to gain skills of practicing scientists. Supported in part by NSF‐DUE #0833268.
Regulatory ubiquitylation during the response to DNA double‐strand breaks
Authors: Durocher Daniel
Published: June 2021

The chromatin‐based response to DNA double‐strand breaks (DSBs) is characterized by the accumulation of DNA repair factors and DNA damage signaling molecules within a large domain that surrounds the lesion. This response is largely dependent on ATM‐dependent phosphorylation but also on chromatin ubiquitylation. Indeed, the RNF8 and RNF168 E3 ubiquitin ligases are necessary for the accumulation of proteins such as 53BP1, BRCA1 and RAD18 at sites of DNA damage. The critical importance of this pathway is manifested by the observation that biallelic mutations in the RNF168 gene results in an ataxia‐telangiectasia‐like syndrome referred to as RIDDLE. We are interested in understanding how this pathway is regulated and how ubiquitin‐dependent protein interactions orchestrate the hierarchy of protein recruitment at sites of DNA lesions. I will present our current understanding on the regulation and organization of this signaling cascade and in particular, I will focus my presentation on addressing how 53BP1 is recruited at site of DNA damage, in a ubiquitin‐dependent manner.
Site‐Specific Analysis of O‐Fucose and O‐Glucose Glycans on Notch
Authors: Haltiwanger Robert S. , Rana Nadia , Kakuda Shinako , Hwang Ga‐Ram , Tan Eugene , Takeuchi Hideyuki
Published: June 2021

The extracellular domain (ECD) of the Notch receptor contains up to 36 tandem Epidermal Growth Factor‐like (EGF) repeats, many of which are modified at consensus sites with one or both of two unusual forms of O‐glycosylation: O‐fucose and O‐glucose. O‐Fucose can be elongated to a tetrasaccharide, Siaα2–3Galβ1–4GlcNAcβ1–3Fucα‐O‐Ser/Thr, and O‐glucose to the trisaccharide Xylα1–3Xylα1–3Glcβ‐O‐Ser. Genetic, cell biological, and biochemical studies reveal that both O‐fucose and O‐glucose glycans are essential for Notch function, and elongation past the monosaccharide modulates Notch function. In order to understand the molecular mechanism by which these glycans affect Notch activity, the presence and structure of the glycans at specific sites must be determined. We have used nano‐LC‐MS/MS glycoproteomic methods to map glycans to predicted sites on mouse Notch1 expressed in cells in the presence or absence of β3GnT's of the Fringe family (Lunatic, Manic, or Radical Fringe). We have also mapped glycans on Drosophila Notch expressed in cells in the presence or absence of Fringe. Using semi‐quantitative mass spectral methods, we have analyzed site occupancy and extent of elongation at each site. Our results suggest that individual O‐fucose or O‐glucose sites are modified at high but variable stoichiometries, and elongation beyond the monosaccharide is site specific. Supported by NIH grant GM061126.
Molecular dynamics of endomembrane structure and function
Authors: Lippincott‐Schwartz Jennifer Anne
Published: June 2021

Emerging visualization technologies are playing an increasingly important role in the study of endomembrane structure and function, capturing membrane processes at the level of whole organisms down to single molecules. Recent developments in probes, techniques, microscopes and quantification are dramatically expanding the areas of that can be analyzed through imaging. Photoactivatable fluorescent proteins (PA‐FPs) have been particular fruitful in this regard. They become bright and visible upon being exposed to a pulse of UV light. This allows selected populations of proteins to be pulse‐labeled and tracked over time. Used for in cellulo pulse chase experiments, the PA‐FPs have helped clarify mechanisms for biogenesis, targeting, and maintenance of organelles as separate identities within cells. PA‐FPs have further permitted the development of single molecule‐based superresolution (SR) imaging, which dramatically improves the spatial resolution of light microscopy by over an order of magnitude (~10–20 nm resolution). Involving the controlled activation and sampling of sparse subsets of photoconvertible fluorescent molecules, single molecule SR imaging offers exciting possibilities for obtaining molecule scale information on biological events occurring at variable time scales. Here, I discuss several examples where we have used these new fluorescent imaging techniques to dissect different membrane trafficking topics, including the formation of autophagosomes, the dynamics of mitochondria, and transport through the secretory pathway.
Novel G protein‐ and GPCR‐Regulated Oncogenic Signaling Circuitries
Authors: Gutkind J. Silvio
Published: June 2021

The family of G protein‐coupled receptors (GPCRs) constitutes the largest group of cell surface proteins involved in signal transduction. GPCRs participate in a wide variety of physiological and pathophysiological functions, and are the target of 50–60% of all current therapeutic agents. This large receptor family plays important roles in normal and tumor cell growth. For example, the Kaposi's sarcoma (KS) associated herpesvirus (KSHV), the infectious cause of KS, expresses an oncogenic constitutively active GPCR, vGPCR, thus providing a direct link between G protein‐linked receptors and viral‐associated malignancies. Recent large cancer sequencing initiatives have revealed an unexpected and surprisingly high incidence of GPCR mutations, ranging from 5% to nearly 30%, in some of the most prevalent human malignancies. Activating mutations in Gαs have been observed in multiple tumors, while genes for both Gαq family members, Gαq (GNAQ) and Gα11 (GNA11), have been recently identified in approximately 80% of uveal melanomas, where they represent the driving uveal melanoma oncogene. How Gαq and its coupled receptors transduce mitogenic signals is still unclear, due to the complexity of signaling events perturbed upon Gq activation. Using a synthetic biology approach and a genome‐wide RNAi screen in drosophila cells, we have found that a highly conserved guanine nucleotide exchange factor, Trio, is essential to activate Rho‐ and Rac‐regulated signaling pathways acting on JNK and p38, and to transduce proliferative signals from Gαq to the nucleus independently of PLC‐β. Evidence will be presented that while many biological responses elicited by Gq depend on the transient activation of second messenger system, Gq utilizes a hardwired protein‐protein interaction‐based signaling circuitry to achieve the sustained stimulation of proliferative pathways, thereby controlling normal and aberrant cell growth. This knowledge may provide opportunities for the development of new G protein‐ and GPCR‐targeted treatment options in cancer.
Tracking of serum lipid levels and anthropometric measures from 3–4y to 7–8y
Authors: Vitolo Marcia Regina , Campagnolo Paula Dal Bó
Published: June 2021

Objective

to evaluate the tracking effect of serum lipid levels and anthropometric measures from 3–4y to 7–8y.

Methods

Children were enrolled in the study from birth to 7–8 years. Total cholesterol (TC), HDL, LDL, triglycerides (TG), body mass index (BMI) and waist‐to‐height ratio (WHtR) were obtained at 3–4 years (n=327) and again at 7–8 years (n=315)

Results

The correlation coefficients for TC, HDL, LDL, and TG in the two assessed periods (n=238) were 0.60, 0.64, 0.62 and 0.40 respectively. For BMI and waist‐to‐height ratio, the coefficients were 0.70 and 0.43 respectively. After adjusting for sex, skin color, mother's education and anthropometric variables, it was observed that the children with altered TC at 3–4 years presented a 1.30 times greater risk (IC95% 1.16–1.46) of having altered TC at 7–8 years. For TG, LDL and HDL the relative risks were 1.22 (IC95% 1.10–1.35), 1.33 (IC95% 1.16–1.53) and 1.39 (IC95% 1.29–1.50) respectively. The children who were overweight at 3–4 years presented a 1.44 times greater risk (IC95% 1.31–1.58) of being overweight at 7–8 years when adjusted for sex, mother's education and skin color while for waist‐to‐height ratio, the RR was 1.18 (IC95%1.25–1.10) using the same adjustments.

Conclusion

Lipids disorders, overweight and high waist‐to‐height ratio in preschool age predicts these outcomes at school age. Research funding: CNPq
Hyperhomocysteinemia (Hcy) predicts small vessel MRI pathology and cognitive impairment with high amyloid‐B‐peptide degrading proteases in the NAME elderly cohort
Authors: Rosenberg Irwin , Scott Tammy , Bhadelia Rafeeque , Qiu Wendy
Published: June 2021

Although Alois Alzheimer's 1907 description of brain pathology in a pre‐senile dementia patient emphasized vascular pathology with deposition of amyloid‐like substances in brain tissue, current definition of Alzheimer's disease (AD) has often excluded vascular pathogenesis. The relationship between cerebrovascular (CBV) pathologies and the amyloid pathology in AD is also unclear. We have studied 318 multi‐ethnic elderly in the Nutrition Aging and Memory Study (NAME) with nutritional, cognitive, and magnetic resonance imaging assessments and found a relationship of small vessel pathology (infarcts and white matter abnormalities) with high blood homocysteine (Hcy) and cognitive impairments, and also noted an association of small vessel infarcts (SVI) to elevated amyloid‐B‐peptide degrading enzymes. Total CBV pathology, particularly SVI (P=.007) and periventricular white matter hyperintensities (P=.04), was associated with elevated fasting Hcy which was inversely related to measures of executive cognitive function (P=.04). SVI, in turn was related to elevated amyloid‐B‐peptide degrading enzyme activity (P=.02). These observations of small vessel pathology in brain with high Hcy and cognitive impairment and now with B‐amyloid processing emphasize the importance of considering vascular elements of age‐related dementia and even the relations of CBV and B‐amyloid pathogenesis in AD.
Iron Status is Related to Cognitive Performance: A Longitudinal Analysis of Data from the InCHIANTI Study
Authors: Chen Lenis , Patel Kushang V. , Murray‐Kolb Laura E.
Published: June 2021

Iron deficiency and cognitive performance are global concerns, but longitudinal analyses of their relation in the elderly are almost nonexistent. This study's aim is to investigate the relation between iron status, characterized by multiple blood measures, and cognitive performance in the elderly over time (n= 1153, male (502), female (651); baseline age=65–102 y). Data is from InCHIANTI, an Italian study of elderly mobility. Iron measures include a complete blood count, ferritin, and transferrin receptor and are used to categorize individuals as iron deficient anemic (IDA), iron deficient (ID), iron sufficient (IS), or iron overload (IO). Cognitive measures include the Mini‐Mental State Examination (MMSE) and the Trail Making Test (TMT) A and B, each measured four times over 10 years. Longitudinal analyses using GEE and Tobit models yield a lower MMSE score in IDA compared to IS individuals (p<0.05) and a slower TMT A score in ID compared to IS individuals (p<0.05), controlling for demographics, smoking, and alcohol. Tobit models also yield a slower TMT B score in IDA compared to IS individuals (p<0.05), controlling for TMT A, demographics, smoking, alcohol, nutritional factors, depressive symptoms, and selected medical conditions. In sum, poor iron status may put some elderly at risk for cognitive decline. The importance of screening and treating poor iron status may be critical to elderly cognitive health.

Grant Funding Source: This research was supported in part by the Intramural Research Program of the National Institute on Aging, NIH, and a Procter & Gamble Dissertation Research Award
The effect of two doses of vitamin D3 (400 IU vs. 2000 IU/d) on serum 25‐hydroxyvitamin D in children with Crohn's disease
Authors: Wingate Kirstin Emma , Jacobson Kevan , Issenman Robert , Brill Herbert , Barker Collin , Israel David , Carroll Matthew , Weiler Hope , Lamers Yvonne , Barr Susan I. , Green Tim J.
Published: June 2021

Vitamin D is crucial for Crohn's disease (CD) patients to maximize bone mineral density and because vitamin D insufficiency has been linked to increased disease activity. We tested whether 2000 IU/d (vs. 400 IU/d) of vitamin D3 yields a higher proportion of children with CD with serum 25‐hydroxyvitamin D (25OHD) concentration ≥ 50 or ≥ 75 nmol/L. 83 patients (8–18 yr) with quiescent CD (Pediatric Crohn's Disease Activity Index (PCDAI) ≤ 10) were randomized to either 400 or 2000 IU/d for 6 months. Clinical and biochemical data were collected at baseline, 3 months and 6 months. Using an intention to treat analysis, at 6 months subjects receiving 2000 IU (vs. 400 IU) were more likely to achieve 25OHD ≥ 75 nmol/L (75% vs. 34%; χ2 =13, P<0.001), but proportions ≥ 50 nmol/L did not differ (94% vs. 91%). After adjustment for baseline 25OHD, mean (95% CI) serum 25OHD was higher in the 2000 IU group than the 400 IU group, 90 (84–96) vs. 67 (60–73) nmol/L (p<0.001), respectively. Disease activity assessed by the PCDAI, and serum bone specific alkaline phosphatase concentrations, were similar between groups. Vitamin D supplementation of 2000 IU/d allows most children with quiescent CD to reach serum 25OHD concentrations of ≥ 75 nmol/L, while 400 IU/d is associated with concentrations ≥ 50 nmol/L.

Funding: University of British Columbia Vitamin Research Fund
Serum vitamin D status of New Zealanders: results from a national nutrition survey
Authors: Skeaff Clark Murray , Williams Sheila M , Brown Rachel C , Parnell Winsome R
Published: June 2021

Serum 25‐hydroxyvitamin D concentrations were measured, using LC‐tandem mass spectrometry, in 3009 individuals, 15 y or over, participating in the 2008/09 New Zealand Adult Nutrition Survey. Mean serum 25‐hydroxyvitamin D concentration was 61 nmol/L (95%CI, 59 to 63 nmol/L) and was highest in Jan, at 79 nmol/L (71, 86), and lowest in Sep, at 47 nmol/L (44, 51). The prevalence of serum 25‐hydroxyvitamin D concentrations below the deficiency level of 25 nmol/L was 6% (95%CI, 5 to 7%) and below the recommended target of 50 nmol/L was 37% (34, 40). The results of multiple regression analysis showed that the adjusted mean serum 25‐hydroxyvitamin D concentration was 11 nmol/L (95%CI, 8 to 14) lower in Pacific than “New Zealand European and Other” people, 7 nmol/L (4, 10) lower in obese than normal weight individuals, 10 nmol/L (6, 14) lower in those in highest compared with lowest category of economic deprivation, and 13 nmol/L (7, 18) lower at the highest compared with lowest latitude in the Country. Approximately one third of New Zealanders do not meet the recommended targets for serum vitamin D status. Funding: The Ministry of Health, New Zealand, funded the 2008/09 New Zealand Adult Nutrition Survey.
Anti‐inflammatory activities of Lessertia frutescens (Sutherlandia) extract in murine macrophages
Authors: Lei Wei , Browning Jimmy , Eichen Peggy Ann , Lu Chi‐Hua , Folk William , Sun Grace , Fritsche Kevin
Published: June 2021

Introduction

Lessertia frutescens (Sutherlandia) is a medicinal plant native to southern Africa and is traditionally used in various inflammatory situations. We sought to characterize the bioactivity of an ethanolic extract from Sutherlandia (SE) using a murine macrophage cell line (RAW 264.7) and primary murine macrophages.

Experimental Design

Cells were exposed to various concentrations of SE for 30 min, then stimulated with IFNγ along with various toll‐like receptor (TLR) ligands for 20 hours. The production of nitric oxide (NO), several pro‐inflammatory cytokines/chemokines, as well as the expression of iNOS protein was evaluated 20 hr later.

Results

SE treatment significantly and dose‐dependently reduced NO production induced by the TLR5 ligand, flagellin, TLR4 ligand, LPS, and TLR2/6 ligand, Pam2CSK. Similar effects were observed for RAW 264.7 cells and primary murine macrophages. The impact of SE on iNOS protein expression was consistent with the observed reductions in NO production. SE treatment also diminished the production of various pro‐inflammatory cytokines and chemokines upon stimulation of macrophages with IFN‐γ and TLR ligands.

Conclusions

Sutherlandia ethanolic extract has potent anti‐inflammatory activities in murine macrophages. Funding from the Office of Dietary Supplement, NIH: P50 AT006273‐01.

Grant Funding Source: ODS, NIH
Protein Intake at Breakfast is Associated with Reduced Energy Intake at Lunch: An analysis of NHANES 2003–2006
Authors: Rains Tia M , Maki Kevin C , Fulgoni Victor L , Auestad Nancy
Published: June 2021

Using the National Health and Nutrition Examination Surveys 2003–2006, we evaluated associations of protein intake at breakfast and energy consumption at lunch in children 9–18 yr (n=2627) and adults ≥19 yr (n=6390). Inclusion criteria included men and non‐pregnant, non‐lactating women with a reliable 24‐hr dietary recall. Breakfast, lunch, and dinner meals were self‐defined by participants. Linear regression was used to assess the associations between kcal/kg body weight (BW) of protein intake at breakfast and energy intake at lunch after adjustment for age, ethnicity, sex, and poverty income ratio. Absolute protein intake (g/kg BW) was higher in children (1.6) vs. adults (1.1), particularly male children (1.8) and adults (1.2) vs. female children (1.5) and adults (1.0). The majority of protein was consumed at dinner (40% and 42%, respectively), versus lunch (31% both ages) and breakfast (16% and 15%, respectively). Higher protein kcal/kg BW at breakfast was associated with lower energy intake/kg BW at lunch in children (β= −0.76; p=0.042) and adults (β= −0.53; p=0.019). Conversely, higher non‐protein kcal/kg BW at breakfast was associated with higher total energy intake/kg BW at lunch in children (β= 0.32; p<0.001) and adults (β = 0.29; p<0.001). These results are consistent with findings from acute trials showing enhanced satiety following intake of protein at a morning meal versus carbohydrate and fat.
Effects of capsaicin on energy expenditure, fat oxidation, appetite profile and energy intake in negative energy balance
Authors: Janssens Pilou , Hursel Rick , Martens Eveline , Westerterp‐Plantenga Margriet
Published: June 2021

Capsaicin (CAPS) increases satiety and energy expenditure. We investigated the 36h effects of CAPS on EE, substrate oxidation, appetite profile and ad libitum intake during 25% negative energy balance. 7 female and 8 male subjects, age 29.7±10.8y, BMI 23.3±2.9kg/m2 underwent four 36h sessions in a respiration chamber. They received 100% or 75% of their daily energy requirements at 100%Control, 100%CAPS, 75%Control and 75%CAPS (dosage 2.56 mg (1.03 g of red pepper, 39.050 SHU) per meal. At 75%CAPS vs. 100%Control, diet‐induced thermogenesis (DIT), resting energy expenditure (REE) and sleeping metabolic rate (SMR) did not differ from 100%Control, while at 75%Control these were lower (all p<0.05); Fat oxidation at 75%CAPS vs. 100%Control (p=0.03) was higher, but not at 75%Control. Respiratory quotient (RQ) decreased more at 75%CAPS (p=0.04) than at 75%Control (p=0.05) vs. 100%Control. Satiety (p<0.01) and fullness (p<0.01) were higher and desire to eat (p<0.05) was lower at 100%CAPS vs. 100%Control. Ad libitum intake (p=0.07) and overconsumption (p=0.06) tended to decrease in 100%CAPS vs. 100%Control. In conclusion, in negative energy balance CAPS counteracted decreases in SMR, DIT and REE, and increased fat oxidation relatively more in negative energy balance. CAPS tended to prevent overeating during ad libitum intake and suppressed the orexigenic and enhanced anorexigenic sensations in energy balance.

Grant Funding Source: McCormick EMEA and the McCormick Science Institute
Amino acid infusion attenuates skeletal muscle protein breakdown in children with severe burns
Authors: Porter Craig , Cotter Matthew , Herndon David N , Sidossis Labros S , Børsheim Elisabet
Published: June 2021

Following a severe burn, skeletal muscle amino acids (AA) are mobilized to act as precursors for wound healing, the immune response and acute phase protein synthesis. The fact that the hypermetabolic, hyperinflammatory stress response to burn injury persists for several years post injury, suggests that sustained exogenous AA provision may play an important role in providing adequate AAs for the pathophysiological response to burns, thus attenuating skeletal muscle protein breakdown (MPB).

Twelve pediatric patients (11.9±4.9 years) with large burns (55±15% of total body surface area) (mean±SD) underwent stable isotope infusion studies 22±3 months post injury. A primed constant infusion of L‐[ring‐2H5] phenylalanine was used to assess skeletal muscle AA kinetics in the fasted state and during a three hour AA infusion.

MPB was reduced by AA infusion (428±73 vs. 237±37 nmol·min−1 100ml leg volume−1, P<0.05), resulting in significant improvement in AA retention across the leg (synthesis‐breakdown) relative to the fasted period (−72±19 vs. 41±26 nmol·min−1 100ml leg volume−1, P<0.05) (mean±SEM). Muscle protein synthesis (MPS) did not significantly change in response to AAs.

These findings indicate that AA infusion improves skeletal muscle AA retention in children with severe burns two years post injury by attenuating MPB, not by elevating MPS. This suggests that adequate AA provision plays an important role in maintaining muscle mass in burned patients long after wound closure and discharge from hospital.

Supported by the National Institutes of Health (P50‐GM60338) and Shriners Hospitals for Children (84090, 84080 and 71006).