bluuebunny/crossref_metadata_2025 huggingface dataset:
Aortic Carboxypeptidase‐Like Protein Enhances Lung Myofibroblast Differentiation
Authors: Tumelty Kathleen E. , Smith Barbara D. , Layne Matthew D.
Published: June 2021

Idiopathic pulmonary fibrosis (IPF) is characterized by the accumulation of smooth muscle α‐actin (SMA) positive myofibroblasts and elevated transforming growth factor β (TGFβ) signaling which result in extracellular matrix (ECM) accumulation and remodeling in the diseased lung. Aortic Carboxypeptidase‐ Like Protein (ACLP) is an ECM protein secreted by smooth muscle cells and myofibroblasts; ACLP knockout mice are protected from drug‐induced IPF. However, the mechanism of ACLP action is unknown. Because of ACLP's expression in the fibrotic ECM and TGFβ's role in fibrosis, we hypothesize that ACLP stimulates the fibroblast to myofibroblast transition by promoting SMA and collagen expression through TGFβ signaling. As primary lung fibroblasts transition into myofibroblasts, ACLP expression preceded SMA and collagen expression. Recombinant ACLP induced myofibroblast markers in lung fibroblasts. siRNA‐mediated knockdown of ACLP slowed and reverted the fibroblast to myofibroblast transition. ACLP treatment induced phosphorylation of Smad3, which along with SMA induction, was dependent on TGFβ receptor kinase activity. These data suggest that ACLP stimulates myofibroblast differentiation via TGFβ receptors. These studies have uncovered novel ACLP signaling events that occur in early stages of IPF and represent a potential therapeutic target. Funding by Department of Biochemistry and HL078869.
Neutrophil‐Derived Microparticles as Novel Effectors in Joint Disease
Authors: Headland Sarah Emily , Dell'Accio Francesco , Perretti Mauro
Published: June 2021

Microparticles (MPs) are small membrane‐bound vesicles released by cells upon activation. Numerous reports have detected MPs in the synovial fluid of Rheumatoid Arthritis (RA) patients. Whilst Tcell‐ derived MPs activate synoviocytes, recent reports have shed light on the possible anti‐inflammatory phenotype of neutrophilderived MPs, challenging the linear model of inflammation. The aim of the study is to unveil the role of neutrophil‐derived MPs in RA, particularly in the context of cartilage biology. Microparticles generated from human neutrophils were characterised by flow cytometry and tested for chondroprotective efficacy in a C28/I2 micromass model of cartilage turnover. These experiments revealed protective actions. Investigation in whole cartilage explants indicated chondroprotection (demonstrated by safranin O staining) as studied over a seven‐day period. Microparticle entry into cartilage was also investigated using confocal microscopy. In conclusion, we report novel biological functions of neutrophil MPs with potential relevance to cartilage biology and arthritis.

Supported by Oliver Bird Studentship Scheme QMUL/KCL
Computational imaging and modeling approaches reveal mechanisms driving myocardial precursor movements
Authors: Rongish Brenda J , Aleksandrova Anastasiia , Cheuvront Tracey , Kosa Edina , Czirok Andras
Published: June 2021

Transformation of planar cardiac progenitor fields into a multilayered tubular heart involves cell and tissue movements in four dimensions. Our objective was to define the forces driving midline myocardial progenitor movements. Imaging of embryos with fluorescence labeled myocardial and endodermal cells demonstrated that myocardial progenitor fields undergo coordinated deformation leading to anterior displacements relative to the endoderm. Microincision mapping implicated endodermal folding during foregut morphogenesis as one force driving midline myocardia movements. Cell shape changes and contraction were also observed at the medial myocardial field border, and pharmacological inhibition of myocardial Rho kinase signaling resulted in decreased endodermal tissue motion. Computational modeling reproduced the myocardial field folding and medial contraction, while simulated incisions reproduced observed post‐surgery cardiac phenotypes. We conclude that antero‐medially directed movement of cardiac progenitors to the site of tubular heart assembly relies on: 1) endoderm folding to drive the convergence at the midline and 2) deformations intrinsic to the myocardial primordia, to mediate movement in the anterior direction and to reposition the myocardia along the dorso‐ventral embryonic axis. Collectively these result in the optimal orientation for myocardial tube fusion at the midline.
Neuronal migration in the adult vertebrate brain
Authors: Lois Carlos
Published: June 2021

Most vertebrate species add new neurons to existing brain circuits throughout life, a process thought to be essential for tissue maintenance, repair, and learning. How these new neurons migrate through the mature brain and which cues trigger their integration within a functioning circuit is not known. We are studying the process of neuronal migration during adult neurogenesis using a combination of genetic labeling and in vivo imaging by 2‐photon microscopy. We observed that in adult songbirds most young newly‐generated neurons exhibit a multipolar morphology, extend dynamic processes that explore extracellular space, and migrate in a wandering manner. After 蝤2 weeks, cells stop migration in close proximity to resident neurons and begin to integrate into the circuit. These data reveal a novel form of neuron migration involved in the addition of new neurons to the postnatal brain that is not directed by pre‐established routes.
Multiple Catalytic Promiscuity: Specificity and Efficiency in the Alkaline Phosphatase Superfamily
Authors: Hollfelder Florian
Published: June 2021

‘Promiscuous’ enzymes possess additional activities in addition to their native ones, challenging the textbook adage “one enzyme – one activity”. In particular the question arises, whether efficiency and specialisation are inextricably linked. The observation of strong promiscuous activities in the alkaline phosphatase (AP) superfamily ‐ where one active site can catalyse up to six chemically distinct hydrolytic reactions with promiscuous second order rate accelerations between 109 and 1017‐ suggests that even broadly promiscuous catalysis can be rather efficient. Mechanistic and structural studies are used to delineate how efficiency and specificity can be combined and managed. We demonstrate that crosswise promiscuity relationships in the AP superfamily indicate that an enzyme is ‘pregnant’ with another activity, i.e. has the potential to be mutated or evolved into a new catalyst. These catalysts are multifunctional generalists that have won additional activities, at low trade‐off cost to the other existing activities. In particular, we use picoliter water‐in–oil emulsion droplets produced in microfluidic devices as high‐throughput screening reactors and present a workflow that allows screening of >;106 clones and allows successful selections, where lower throughput approaches have failed.
Enzyme recruitment and the evolution of new metabolic potential
Authors: Miller Brian G.
Published: June 2021

Processes such as the acquisition of antibiotic resistance by pathogenic bacteria and the bioremediation of anthropogenic toxins by microorganisms demonstrate that the evolution of new biological catalysts is an ongoing process. What is the origin of these new activities, and how do they evolve to yield highly specialized enzymes? The answers to these questions are not well understood, especially at the molecular level. The goal of our research is to combine microbial genetic selection strategies with mechanistic enzymology to identify new catalysts and investigate their evolutionary potential. In this presentation, I will discuss recent experiments in our laboratory in which we challenged E. coli K‐12 for growth on several metabolically inert compounds. High‐level expression of specific genes was found to afford an expansion of the metabolic capabilities of this bacterium by virtue of latent catalytic activities embedded within the genome. I will discuss the experimental strategies that led to the identification of these promiscuous catalysts and describe the preliminary characterization of these activities. The implications of these findings upon the natural and directed evolution of enzymes with useful applications will also be discussed.
PDB as a public resource for enabling protein science
Authors: Berman Helen M.
Published: June 2021

The Protein Data Bank (PDB) was established in 1971 as a archive for the three dimensional structures of biological macromolecules. The PDB provides a repository for scientists who generate the data, as well as as an access point for researchers and students to find the information needed to drive additional studies.

Today, the PDB contains and supports online access to more than 85,000 biomacromolecules that help researchers understand aspects of biology, including medicine, agriculture, and biological energy. The growth in the number and complexity of the structures in the archive is a result of marked changes in technology, structure determination methods, and community involvement.

The PDB archive is managed by the Worldwide Protein Data Bank (wwPDB), as supported by: RCSB PDB (NSF DBI 0829586, NIGMS, DOE, NLM, NCI, NINDS, and NIDDK), PDBe (EMBLEBI, Wellcome Trust, BBSRC, NIGMS, and EU), PDBj (NBDCJST) and BMRB (NLM).
ESCRTing Receptor Down‐Regulation: Assembly and Function of the ESCRT‐III Complex
Authors: Emr Scott David , Buchkovich Nick , Henne Mike M.
Published: June 2021

The Endosomal Sorting Complexes Required for Transport (ESCRTs) comprise a highly conserved set of five protein complexes that function as a ubiquitin‐dependent protein sorting machine which recognizes and directs the down‐regulation of membrane proteins including signaling receptors. Recent studies have identified the ESCRT‐III complex as a vesicle budding machine that can sort cargo into intraluminal vesicles (ILV) which bud into an endosomal multi‐vesicular body (MVB). The mechanisms by which soluble ESCRT‐III subunits (Vps20, Snf7, Vps24 and Vps2) mediate ILV budding are not yet known. Here, we present data indicating that conformational changes within the ESCRT‐III subunit Snf7 (displacement of helix‐5) activate Snf7 for membrane binding. Using electron microscopy techniques, we directly visualize ESCRT‐III assembly on lipid monolayers. Activated Snf7 generates long ~9nm‐wide protofilaments composed of two ~4nm sub‐filaments. These protofilaments form 2‐D spiral arrays on the monolayers. Strikingly, the addition of Vps24 and Vps2 transforms the flat spirals into 3‐D membranesculpting helices. Finally, addition of ESCRT‐II stabilizes the formation of ESCRT‐III rings that are ~65 nm in diameter. We will discuss the role of domains in ESCRT‐III subunits that function in cargo capture, membrane binding/deformation and scission during intraluminal vesicle formation.
Modeling the impact of revisions to Daily Values assuming that current % Daily Values in fortified foods are maintained
Authors: Murphy Mary M. , Spungen Judith H. , Barraj Leila M. , Bailey Regan L. , Dwyer Johanna
Published: June 2021

The Daily Values (DVs) on the Nutrition Facts Panel are based on 1968 RDAs. There is debate about which reference values should be used to update label DVs: population‐weighted (w) or highest (h) values of the current EARs or RDAs. Using NHANES 2007–8 data, we estimated current intake of 15 vitamins and minerals (V/M) and modeled intake in each of 4 hypothetical DV scenarios (wEAR, hEAR, wRDA, hRDA) for nutrients from fortified foods. In each scenario, levels of fortified V/M were adjusted to maintain the current % DV in fortified foods, keeping levels of other nutrients constant. Usual nutrient intakes and % with usual intakes < EAR were estimated with C‐SIDE for the population 4+ y (n= 7976) and subpopulations. Nutrient intakes and adequacy of intake changed minimally overall. The % of the population 4+ y with usual intakes < EAR in the current, wEAR and hRDA DV scenarios were 48, 49 and 46% for calcium; 96, 96 and 94% for vitamin D; and 44, 54 and 49% for vitamin A. Compared with the current scenario, potential increases in % < EAR were observed in the wEAR scenario for iron and folate among females, and for vitamin B6 and zinc among females and older adults. Declines in the % with vitamin C intakes < EAR were observed in the hRDA DV scenario. Results of this modeling exercise will help to inform decisions in revising the DVs for the Nutrition Facts Panel. Supported by the Fortification Committee, The International Life Sciences Institute, NA.
Employing the Water Balance Questionnaire for the evaluation of water balance in adults, pregnant women and elderly
Authors: Kapsokefalou Maria , Malisova Olga , Zampelas Antonis , Bountziouka Vassiliki , Panagiotakos Demosthenes
Published: June 2021

Water balance is a euhydration index reflecting water intake and loss. It may be evaluated with the Water Balance Questionnaire (WBQ), a practical validated new tool that estimates intake from frequency intake of foods, beverages and drinking water and loss from excretion of sweat, urine and feces.

The objective was to apply the WBQ for the assessment of water balance in adults (18–65y, stratified for age and sex, n=485 in summer and n=412 in winter), pregnant women (n=300, 100 from each trimester) and elderly (aged 65–95y, n=200) in Athens, Greece.

In adults, in winter water balance was −63±1478 ml/day, intake 2892 ± 987 ml/day and loss 2637 (1810, 3922) ml/day. In summer water balance was −58 ± 2150 ml/day, intake was 3875 ± 1373 ml/day and loss 3635 (2365, 5258) ml/day. In pregnant women water balance was 203 (−577, 971) ml/day, intake was 2917 (2187, 3544) ml/day and loss 2658 (2078, 3391) ml/day; these did not differ between pregnant and non pregnant women or among the three trimesters. Similarly, results in the elderly are reported.

Using the WBQ we observed that a) in summer water needs were higher than those in winter by approximately 1L b) pregnant women have higher water intake than adult women c) various sources contribute to water and energy intake d) beverages contribute approximately 1/5 of total energy intake.

Supported partially by Coca Cola and the European Hydration Institute
Spatial and temporal expression of histone H3 Lysine 9 trimethylation foci by methylseleninic acid treatment
Authors: Rouse Jallah J , Cheng Wen‐Hsing
Published: June 2021

We have recently shown that selenium compounds can induce a senescence response in a manner depending on ataxia‐telangiectasia mutated (ATM), DNA‐dependent protein kinase (DNA‐PK), p53 and reactive oxygen species (ROS). To test the hypothesis that the selenium‐induced senescence response involves epigenetic changes in senescence‐associated heterochromatin foci (SAHF), we determined the expression of histone H3 Lysine 9 trimethylation (H3K9me3), a marker of SAHF, in human primary MRC‐5 cells treated with methylseleninic acid (MSeA, 2 μM) for 2 days, followed by a 7‐day recovery, in the presence or absence of KU55933 (10 μM), an ATM kinase inhibitor, and NU7026 (10 μM), a DNA‐PK kinase inhibitor. Our results showed that MSeA treatment induced the formation of SAHF and H3K9me3 foci. Pre‐treatment of the cells with KU55955 or NU7026 resulted in numerous and smaller foci, and they did not co‐localize with the MSeA‐induced SAHF. These results suggest that the MSeA‐induced senescence response involves epigenetic changes of H3K9me3 in a manner depending on ATM and DNA‐PK.

Grant Funding Source: UMCP
Cruciferous and apiaceous vegetable intake protect colon and prostate against PhIP genotoxicity in Wistar rats
Authors: Kim Jae Kyeom , Warnert Marissa , Gallaher Daniel D , Trudo Sabrina P
Published: June 2021

Apiaceous vegetables inhibit cytochrome P4501As (CYP1As) which activate 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), while cruciferous vegetables induce both PhIP‐activating and PhIP‐detoxifying enzymes (CYP1As and uridine 5¡Ç‐diphosphophate glucuronosyl transferases (UGTs)). In the present study, we fed male Wistar rats diets supplemented with three different vegetable combinations: cruciferous only (21% wt:wt), apiaceous only (21% wt:wt), and both combined (10.5% wt:wt of cruciferous, and 10.5% wt:wt of apiaceous). After six days of feeding, rats were injected with PhIP (10 mg PhIP/kg body wt, dissolved in DMSO) and colon, and prostate tissues were collected for measurement of PhIP‐DNA adducts by LC‐MS/MS. Compared to the control group, apiaceous feeding reduced PhIP‐DNA adducts in the colon by approximately 20% (P<0.05) and in the prostate by approximately 30% (P=0.02). Cruciferous feeding only reduced colonic PhIP‐DNA adducts by 17% with borderline statistical significance (P=0.07). No effect was noted in the combined vegetable group. Although cruciferous and apiaceous vegetables combined did not exhibit synergistic effects, significant effects against PhIP genotoxicity in Wistar rats were achieved from each vegetable group individually at realistic doses in the human diet.

Funding: Healthy Foods, Healthy Lives Institute, U of MN
Longitudinal and secular trends in dietary supplement use: Nurses¡ Health Study and Health Professionals Follow‐up Study, 1986–2006
Authors: Kim Hyun Ja , Giovannucci Edward , Willett Walter C. , Cho Eunyoung
Published: June 2021

Objectives

The objective of this study was to describe the longitudinal and secular trend of dietary supplement use over the past 20 years in two large prospective cohorts.

Methods

Data on use of dietary supplements has been repeatedly collected every 4 years from 1986 to 2006 in the Nurses’ Health Study (NHS) and the Health Professionals Follow‐up Study (HPFS).

Results

In 1986, 74,194 women aged 40–65 years in the NHS and 50,497 men aged 40–75 years in the HPFS responded to a questionnaire about their use of dietary supplements. Prevalence of use of any supplement increased among both women (71.3% to 88.3%) and men (56.4% to 80.7%) from 1986 to 2006. Longitudinal increases in the prevalence of use of vitamin D (2.2 to 32.2% for women and 1.1 to 6.7% for men), folic acid (0.8 to 10.7% for women and 1.1 to 13.8% for men), and fish oil (1.6 to 18.1% for women and 3.3 to 22.2% for men) supplements were observed from 1990 to 2006. However, the use of vitamin A, β‐carotene, vitamin C, and vitamin E supplements peaked in 1994 or 1998 then declined steadily. A secular increase in use of multivitamins, vitamin D, folic acid, and fish oil across same age group was noted.

Conclusions

The use of many types of dietary supplements has increased over time, but the use of antioxidant supplements has continued to decline. The secular increase in the prevalence of use of multivitamins, vitamin D, folic acid, and fish oil supplements across same age group suggests that aging of the population is not the primary reason for the increase.

Grant Funding Source: research grant CA87969 and CA55075 from the National Institutes of Health
Environmental Hygiene, Food Safety and Growth in less than Five Year Old Children in Zimbabwe and Ethiopia
Authors: Ngure Francis Muigai , Humphrey Jean H , Menon Purnima , Stoltzfus Rebecca
Published: June 2021

Childhood stunting remains a significant public health challenge with adverse developmental and health outcomes in life and over generations. This study explored novel causes of poor growth in infants and young children. Using in‐depth observation methods, soil and chicken feces ingestion were identified as key pathways for fecal‐oral transmission of bacteria in infants and young children in rural Zimbabwe. In a cross‐sectional survey, poor environmental hygiene was associated with linear growth faltering (p =0.032), independent of socioeconomic status, infant feeding and recent morbidity, in 24–59 month old Ethiopian children. Significant aflatoxin exposure in mothers was associated with severe stunting in 6 to 59 months old Zimbabwean children in a dose response manner (p=0.035). We identified poor environmental hygiene and aflatoxin exposure as two novel causes of stunting in African children. Existing WASH interventions are not sufficient to protect infants and young children from fecal bacteria ingestion through soil and poultry feces. In addition, existing hygiene interventions do not directly address improving household environmental hygiene. Our findings raise the need for low cost strategies for aflatoxin control and a holistic approach in designing context‐ and age‐specific hygiene interventions to prevent childhood stunting.

Grant Funding Source: Cornell International Institute for Food, Agriculture and Development (CIIFAD); the Department for International Development (DFID), UK and Borlaug Leadership in Agriculture Enhancement Program (LEAP), UC, Davis, USA; Bill & Melinda Gates Foundation.
Supplementation with a Leucine Pulse during Continuous Feeding Stimulates Translation Initiation and Suppresses Protein Degradation Pathways in Muscle of Neonatal Pigs
Authors: Boutry Claire , El‐Kadi Samer W. , Suryawan Agus , Wheatley Scott M. , Orellana Renán A. , Nguyen Hanh V. , Davis Teresa A.
Published: June 2021

Leucine acts as a nutrient signal to stimulate protein synthesis in skeletal muscle. Limited evidence suggests that leucine may suppress protein degradation. Twenty piglets (8‐d‐old) received formula by orogastric tube for 24 h continuously (CON) or by bolus (BOL), i.e., every 4 h for 15 min. For the CON+LEU group, leucine was administered parenterally (800 μmol·kg−1·h−1) every 4 h for 1 h. Protein synthesis in skeletal muscle was greater in CON+LEU and BOL than CON. Ribosomal protein S6 kinase 1 and 4E‐binding protein 1 phosphorylation and active eukaryotic initiation factor (eIF) eIF4E·eIF4G complex formation were higher in muscle of CON+LEU and BOL than CON suggesting increased translation initiation. Eukaryotic elongation factor 2 and AMP‐activated protein kinase‐α phosphorylation was unaffected by treatment. The LC3‐II to total LC3 ratio was lower in CON+LEU and BOL than CON suggesting reduced autophagy‐lysosome activation. There were no differences between groups in indices of the ubiquitin‐proteasome pathway, i.e., Atrogin‐1 and MURF‐1 abundance and FOX03 phosphorylation. In conclusion, administration of a leucine pulse during continuous orogastric feeding increases protein synthesis by stimulating translation initiation and suppresses autophagy‐lysosome, but not the ubiquitin‐proteasome, degradation pathways in skeletal muscle of neonates. (NIH AR444474 and USDA/ARS 6250–51000‐055)
Frequency and determinants of marginal vitamin B12 deficiency in childbearing‐aged women of South Asian and European descent in Metro Vancouver
Authors: Quay Teo A. W. , Schroder Theresa H. , Devlin Angela M. , Barr Susan I. , Lamers Yvonne
Published: June 2021

Low maternal vitamin B12 (B12) status has been associated with an increased risk of neural tube defects (NTDs) and insulin resistance. It was estimated that 34 % of NTD cases in Canada may be linked to low B12 status in the era of folic acid fortification. Due to the early effects of B12 status on pregnancy outcome, it is crucial for women to be B‐vitamin adequate before conception. South Asians are one of the most vulnerable ethnic groups for B12 inadequacy and are one of the largest ethnic minorities in Vancouver.

The objectives of this study are to assess whether South Asian women of childbearing age are more likely to be marginally B12 deficient than women of European descent in the Metro Vancouver area and to determine whether select demographic, dietary, and genetic determinants increase a woman's risk to be marginally B12 deficient.

In a convenience sample of 300 healthy non‐pregnant females (19 – 35 y), B12 status is assessed using serum B12, holotranscobalamin, and plasma methylmalonic acid. Sociodemographic status, supplement use, and usual eating habits are assessed by questionnaires.

The frequency of marginal B12 deficiency was estimated to be 16% with a trend for higher frequency in South Asian women. The research outcomes will aid in identifying risk factors of B12 deficiency by ethnicity and contribute to the evaluation of periconceptional supplement recommendations.

Grant Funding Source: ‘FNH Vitamin Research Fund’ UBC
ENDOTHELIAL CELLS CONTRIBUTE TO INFLAMMATION AND FIBROSIS IN BLEOMYCIN INDUCED LUNG INJURY
Authors: Leach Heather Gail , Chrobak Izabela , Trojanowska Maria
Published: June 2021

In this study we aimed to identify the contribution of endothelial cells (ECs) to inflammation and fibrosis induced by bleomycin lung injury. C57Bl/6 mice were injected daily with Sub‐Q bleomycin. Lungs were harvested after 14 or 28 days for analysis of total tissue by staining or FACS anaysis. ECs were isolated at day 28 by expression of surface markers (CD31+CD45−) and RNA was collected for qPCR analysis, results were confirmed by IHC. Analysis of total tissue showed an increase in macrophages by tissue staining of the Mac3 antigen and FACS analysis of CD11b+ CD11c‐ cells. In sorted ECs, expression of adhesion molecules showed up‐regulation in E‐Selectin (1.7 fold), P‐Selectin (2.4 fold, p=0.05) and CD34 (2.3 fold, p=0.01) mRNA levels. Chemokine mRNA expression was also increased in CCL2/MCP1 (2.8 fold, p=0.004), CXCL1 (1.6 fold) and CXCL2 (3.5 fold, p=0.002). Profibrotic molecules were altered, showing increases in CTGF (1.6 fold, p=0.03), PAI‐1 (3.3 fold, p=0.02), fibronectin (2.8 fold, p=0.03) and FSP1 (10.2 fold, p=0.04). Expression of selectins and chemokines suggests that EC activation plays an integral role in homing of macrophages, contributing to tissue injury after bleomycin. Further expression of pro‐fibrotic mediators in endothelial cells contributes to a sustained pro‐fibrotic environment. These results suggest that ECs play an active role in inflammation and fibrosis after bleomycin injury.
miR‐21 inhibition overcomes ethanol suppression of rat liver regeneration
Authors: Juskeviciute Egle , Dippold Rachael P. , Swarup Aditi , Hoek Jan B.
Published: June 2021

miR‐21 has been identified as a pro‐proliferative miRNA. It is overexpressed in many types of tumors. miR‐21 also increases its expression during liver regeneration following partial hepatectomy (PHx) in the rat in apparent agreement with this pro‐proliferative role. However, chronic ethanol treated animals which have impaired liver regeneration show even stronger up‐regulation of miR‐21 expression than their corresponding pair‐fed calorie‐matched controls or chow fed animals (Dippold et al., 2012).

To investigate the role of miR‐21 in liver regeneration, we treated rats with a locked oligonucleotide antisense to miR‐21 (AM21). Injection of AM21 72 h prior to PHx followed by a second injection immediately after the surgery suppressed expression of miR‐21 by >;95% in the regenerating rat liver. Inhibition of miR‐21 resulted in up‐regulation of expression of such validated miR‐21 targets as RhoB, E2f1, Il6ra, Nfib and Tgfbr2. AM21 treatment did not have any significant effect on cell cycle progression markers, such as cyclins D, E, A, PCNA either at the mRNA or the protein level in chow fed animals. Remarkably, however, AM21 treatment promoted cell cycle progression and allowed recovery of DNA synthesis 24h after PHx in chronically ethanol treated animals. Thus, miR‐21 is not required for normal progression of liver regeneration after PHx in the rat.

Supported by AA008714, AA018873, AA007463, and AA017261.
Imaging the cellular dynamics and signals that pattern embryos
Authors: Fraser Scott E.
Published: June 2021

Advances in cell biology, genomics and proteomics offer unprecedented knowledge of the constituents within cells and the means by which the cells can interact. Advanced imaging techniques provide a powerful means of integrating this growing data set into a mechanistic understanding of the cellular mechanisms that underlie embryogenesis and organogenesis, by studying the events in the intact system. These powerful techniques are challenged by major tradeoffs between spatial resolution, temporal resolution, and the limited photon budget. This combination of requirements is challenging, but necessary: intravital imaging can only generate accurate data on cell lineages and cell migration if it can capture the three dimensional image of the entire embryo or tissue before any of the cells can move half of the distance separating neighboring cells.

We are attempting to advance these tradeoffs by constructing faster and more efficient microscopes that maintain subcellular resolution. Our new microscope combines the deep penetration of two‐photon microscopy and the speed of light sheet microscopy (often termed SPIM) to generate images with more than ten‐fold improved imaging speed and sensitivity. This two‐photon SPIM is far less subject to light scattering, permitting subcellular resolution to be maintained far better than conventional light sheet microscopes.
Bent Bone Dysplasia Syndrome defines a nuclear role for FGFR2 in skeletal development
Authors: Merrill Amy Elizabeth , Idoni Brian , Neben Cynthia , Salva Joanna , Roberts Ryan , Krakow Deborah
Published: June 2021

Development of the skeleton requires dynamic regulation of osteoprogenitor cell renewal and commitment. These processes are dually promoted by Fibroblast Growth Factor Receptor 2 (FGFR2), as evidenced by congenital disorders resulting from FGFR2 mutations. However, how FGFR2 activity balances proliferation and differentiation is unclear. We have identified unique FGFR2 mutations in Bent Bone Dysplasia Syndrome (BBDS), a disorder deficient in osteoblasts despite abundant osteoprogenitor cells. This phenotype of enhanced proliferation and reduced differentiation suggests these FGFR2 mutations uncouple distinct receptor activities in osteoprogenitor cells. The FGFR2 mutations in BBDS reside in the transmembrane domain, prevent receptor incorporation into the plasma membrane, and consequently reduce receptor responsiveness to secreted FGFs. Despite decreased canonical FGF signaling, mutant FGFR2 enhances a noncanonical nuclear function for FGFR2: we found that FGFR2 acts in the nucleolus where it associates with FGF2 and UBF1 to promote ribosomal DNA transcription. This nucleolar association is enriched by mutant FGFR2 and consequently elevates ribosomal RNA levels in the bones of BBDS patients. Delineation of BBDS reveals that nuclear FGFR2 signaling balances osteoprogenitor cell renewal and commitment by regulating ribosome biogenesis.

Grant Funding Source: March of Dimes 5‐FY12–166, NIH/NIDCR 5 P30 DE020750‐02
Regulating CTD‐Interactions by Ess1‐Dependent Prolyl Isomerization
Authors: Hanes Steven , Atencio David , Barnes Cassandra
Published: June 2021

RNA polymerase II directs the synthesis of mRNAs as well as snoRNAs and some snRNAs. The largest subunit, Rpb1, contains an unstructured C‐terminal domain (CTD) composed of multiple repeats of the heptapeptide, Y‐S‐P‐T‐S‐P‐S. These repeats are located near the RNA exit channel and are bound by a variety of protein complexes that function during different stages of transcription and co‐transcriptional RNA processing. Despite the fact that the CTD is relatively long (26 repeats in yeast, 52 in human), different co‐factor complexes are differentially recruited to the CTD during the transcription cycle. Recruitment is regulated by covalent and non‐covalent modification of residues within the CTD repeat. This regulation is referred to as the “CTD code.” Examples of important covalent modifications are phosphorylation of serines at positions 2, 5, and 7.

We are studying a non‐covalent modification, the cis/trans isomerization of the peptide bond at phosphorylated Ser5‐Pro6 sites. In yeast, this is carried out by a highly‐conserved enzyme that we discovered called Ess1 (Pin1 in humans). Ess1 binds and isomerizes pSer5‐Pro6, and this has profound consequences for the proper recruitment of proteins (e.g. Nrd1, Pcf11) to the RNAP II complex. Cells that lack Ess1 activity fail to suppress cryptic transcription, and cannot efficiently terminate transcription of small ncRNAs and mRNAs, leading to cell death. Ess1‐dependent isomerization of the CTD also seems to be important for histone modification, as ess1 mutants show reduced levels of H3K4‐ trimethylation. We will discuss potential mechanisms for how Ess1 regulates RNAP II transcription and co‐transcriptional processing.
Investigating Roles of Reader Domains in Regulating Activity of Jumonji Histone Demethylases
Authors: Fujimori Danica Galonic
Published: June 2021

Methylation of histones, protein subunits of nucleosome particles within chromatin, has a profound impact on regulation of transcription. This post‐translational modification is controlled by opposing action of histone methyltransferases and histone demethylases, enzymes that install and remove histone methyl marks, respectively. Jumonji histone demethylases are Fe(II)‐ and alpha‐ketoglutarate‐ dependent oxygenases that remove methyl marks from side chain amino groups of lysines. It is postulated that, in analogy to other members of the superfamily, demethylation proceeds by a radical mechanism where hydrogen atom abstraction from the methyl group, followed by oxygen rebound, results in the formation of a hemiaminal intermediate which fragments to release formaldehyde and demethylated product. The precise control of the activity of demethylases is crucial, and misregulation of demethylation is associated with various human diseases. In addition to a catalytic domain that harbors the iron binding site, several families of demethylases also contain reader domains which recognize chromatin modifications. In this talk, our finding on regulation of the catalytic activity of jumonji histone demethylases by their reader domains will be presented.
Vitamin C intake, lead exposure, and oxidative stress in Uruguayan school children
Authors: Roy Aditi , Queirolo Elena , Peregalli Fabiana , Mañay Nelly , Kordas Katarzyna
Published: June 2021

Oxidative stress (OS) is a potential mechanism for lead (Pb) toxicity. Vit C may modify Pb‐induced OS. This study examined the relation between blood lead level (PbB) and OS markers [8‐isoprostane and 8‐hydroxy‐2‐deoxy Guanosine (8‐oxodg)], and the role of vit C intake in modifying the relation between PbB and OS. 6–8 y old children (n=145) from Montevideo, Uruguay were assessed in a cross‐sectional study, including nutrient intake via two 24 hr recalls. Mean±SD PbB was 4.5±2.1 μg/dL, with 29% children having PbB≥ 5 μg/dL. Specific gravity‐adjusted mean±SD urinary 8‐isoprostane and 8‐oxodg were 1.5±1.2 and 50±32.7 ng/mL, respectively. Mean±SD intake of vit C was 57±54 mg/d, with 23% of children not meeting recommended intake (RDA, 25 mg/d). Children with vit C intake below RDA had higher urinary 8‐isoprstane than children who met RDA (p<0.05). PbB was associated with 8‐isoprostane (β=0.1; p<0.05) even after adjusting for serum ferritin, and vit C and zinc intake. Children in the lowest tertile of vit C intake (<30 mg/d) and PbB above median (>;4.9 μg/dL) had 0.9 ng/mL higher 8‐isoprostane than those in the highest tertile of vit C intake (>;62 mg/d) and PbB below median (p<0.05). PbB was not associated with urinary 8‐oxodg. Low vit C intake and even modest elevation in PbB may predispose children to increased OS.

Grant Funding Source: NIEHS Grant 4231251X1
Body fat distribution in preterm and term born children at school age
Authors: Landmann Eva , Huke Verena , Brugger Markus , Strauch Konstantin , Berthold Lars Daniel , Rudloff Silvia
Published: June 2021

As has been shown for children born small for gestational age, low birth weight due to prematurity might be a risk factor for developing increased body fat mass and a higher percentage of intraabdominal adipose tissue which has been shown to be associated with cardiovascular disease, insulin resistance and finally metabolic syndrome. Thus, body composition and abdominal fat distribution was determined in a total of 236 children aged 5 to 7 years. 116 out of these children were born preterm at a gestational age 29.8 ± 2.6 (30; 24–33) weeks [mean ± SD (median; range)] and 120 children were born at term. Body composition was determined by bioelectrical impedance analysis, percentage of intraabdominal adipose tissue by magnetic resonance imaging. Children born preterm were shorter (120 vs. 123 cm, p = 0.0003) and lighter (21.8 vs. 24.3 kg, p = 0.0001) and had a lower body mass index (15.1 vs. 15.9 kg/m2, p = 0.0025) at the age of 5 to 7 years. Children born preterm neither showed increased fat mass nor intraabdominal adiposity.

[Supported by the German Research Foundation (DFG grant no. LA 2428/1–1)]
Polyphenol‐rich red and purple aronia berry extracts inhibit interleukin‐6 from mouse splenocytes.
Authors: Martin Derek , Taheri Rod , Brand Mark , Draghi Andrew , Sylvester Francisco , Bolling Bradley
Published: June 2021

Viking aronia berries are a rich source of dietary polyphenols, but less is known about other aronia genotypes. The objective of this work was to assess the anti‐inflammatory activity of underutilized aronia berries to relative to Viking. Aqueous acetone extracts were prepared from Aronia melanocarpa (black), prunifolia (purple), and arbutifolia (red) berries (n = 5). Extract polyphenols were quantitated by UPLC‐MS and the total phenols assay. Primary mouse splenocytes were stimulated for 12 h by LPS with berry extracts and interleukin‐6 (IL‐6) was determined in media. On an equivalent total phenols basis, Viking had at least 1.5‐fold greater anthocyanins and proanthocyanidins than other accessions. Phenolic acids were highest in the purple UCO47 and red UCO57 accessions. The UCO57 extract inhibited IL‐6 by 75% and was the most potent among the tested aronia extracts. In contrast, Viking inhibited IL‐6 by 32%. Among all aronia accessions, IL‐6 inhibition was correlated more strongly to phenolic acid and flavonoid content than proanthocyanidin and anthocyanin content. Thus, underutilized aronia accessions have in vitro anti‐inflammatory efficacy, and are promising candidates for evaluation in models of chronic disease.

Grant Funding Source: University of Connecticut Diet and Health Initiative
The acute aerobic exercise‐induced increase in amino acid transporter expression adapts to exercise training in older adults
Authors: Markofski Melissa M , Timmerman Kyle L , Dickinson Jared M , Reidy Paul T , Borack Michael , Rasmussen Blake B , Volpi Elena
Published: June 2021

Exercise and nutritional interventions may prevent or delay frailty and sarcopenia in older adults. The OBJECTIVE of this ongoing study is to determine the acute and chronic effects of aerobic exercise +/− essential amino acid (EAA) supplementation on skeletal muscle amino acid (AA) transporter expression. Preliminary data are reported.

METHODS

Healthy untrained older adults (65–85 y; n=10) were randomized into one of two groups: exercise and 15 g EAA supplement (Ex+EAA) or exercise and placebo (Ex+Pla). Acute treatment consisted of 45 mins of walking exercise on a treadmill at ~70% heart rate max (Ex+EAA and Ex+Pla) immediately followed by the assigned supplement or placebo. Chronic treatment involved once daily supplementation (EAA or Pla) plus aerobic exercise 3 times/wk. Real‐time qPCR was used to measure mRNA expression of select muscle AA transporters.

RESULTS

At baseline, CAT1, SNAT2, PAT1, CD98, and LAT1 mRNA expression increased more after Ex+EAA than Ex+Pla. After chronic treatment, only CD98 increased with Ex+EAA. There were no basal pre to post changes.

CONCLUSION

Muscle AA transporter expression increases acutely with Ex+EAA. Exercise training+EAA induces adaptations reducing the acute AA transporter response to these stimuli. Supported by NIH/NIA R01 AG030070 and NIH/NIA R01 AG030070S1

Grant Funding Source: NIH
Post‐infant linear growth is associated with cognitive achievement of 8y‐olds in Ethiopia, India, Peru and Vietnam
Authors: Crookston Benjamin T , Schott Whitney , Dearden Kirk A , Cueto Santiago , Engle Patrice , Georgiadis Andreas , Lundeen Elizabeth A , Penny Mary E , Stein Aryeh , Behrman Jere R
Published: June 2021

Resource allocations for nutrition programs are often based on the assumption that opportunities for long‐term physical and cognitive development close after 2 y. However, cognitive deficits from linear growth failure may be reversible. We used data from Young Lives which includes ~8000 children at 1, 5 and 8 y of age in Ethiopia, India, Peru and Vietnam. We used regression analysis to examine associations between post‐infancy improvement in height not predicted by prior length (unpredicted growth) and cognitive achievement at 8 y. HAZ at 1 y was associated with higher cognitive achievement for all 4 countries and with schooling outcomes (except preschool attendance in Vietnam). In adjusted models, unpredicted change in HAZ from 1 to 8 y was significantly associated with higher scores on standardized tests of math in Ethiopia and India (coefficients of .504 and .509, respectively) and vocabulary (in Ethiopia, India and Peru, 3.079, 2.020, .930, respectively) and appropriate age for grade (.821, .848, .834 and .812 in Ethiopia, India, Peru and Vietnam). We believe this to be the first study to examine the relationship between post‐infancy unpredicted growth and medium‐term child development outcomes. Our results reinforce the gains from addressing nutritional insults not only during infancy but throughout childhood.
The effects of heat stress and Zn intake on the microbial communities in the stomach, ileum, colon and feces of pigs
Authors: Hunt Katherine M , Brooker Sarah L , Sanz‐Fernandez M. Victoria , Gabler Nicholas K , Baumgard Lance H , McGuire Mark A.
Published: June 2021

Heat stress (HS) is associated with harmful inflammatory events in the gastrointestinal (GI) tract that may be connected to the microbial communities therein. Recent work suggests that increased Zn intake may ameliorate inflammatory conditions. To test the effects of HS and Zn intake on GI microbiota, pigs (n = 30, 43 kg BW) were randomized to 120 (Zn control), 220, or 320 ppm Zn intake. Pigs were fed ad libitum, except half the Zn control treatment designated as a pair fed thermoneutral control group (PFTN, 19°C, 61% relative humidity). All remaining pigs were subjected to HS (36°C, 50% relative humidity). Pigs were sacrificed on d1 or d7 (acute vs chronic HS), and microbial contents collected from the stomach, ileum, colon, and feces. Bacteria were identified with pyrosequencing of the 16S rRNA gene. Differences (P < 0.05) were found in the abundances of the bacterial genera in the stomach and the ileum between HS vs PFTN pigs, yet this effect was not apparent in samples from the colon or the feces. Among HS pigs, community structure was altered as a result of acute vs chronic HS in the stomach and ileum. No effect of Zn intake on microbial community structure was observed. These results indicate that HS alters the microbial communities in the stomach and ileum of pigs, and that fecal samples are not adequate to detect changes in the microbiota of the stomach or the small intestine. Supported by IBEST and the Idaho Ag Experiment Station.
Vitamin D supplementation in healthy adolescents does not increase calcium absorption
Authors: Hill Kathleen M , Martin Berdine R , Laing Emma M , Hausman Dorothy B , Hall Daniel B , McCabe Linda D , McCabe George P , Peacock Munro , Lewis Richard D , Weaver Connie M
Published: June 2021

Vitamin D supplementation is widely used in adults to increase calcium absorption. The purpose of this study was to determine the effect of vitamin D supplementation in children on calcium absorption at the seasonal nadir of serum 25D. Healthy black and white boys and girls ages 9–13y (n = 295) in the early stages of puberty (sexual maturation stages 2–3) from northern and southern states in the US (40° and 34°N latitudes, respectively) received 0, 400, 1000, 2000, or 4000 IU/d of vitamin D3 by random assignment for 12 weeks during winter. Baseline and 12‐week calcium absorption was determined from an oral dose of stable isotope 44Ca with a breakfast containing 300 mg calcium. Fasting serum 25D was measured by RIA. At baseline, mean serum 25D was 28 ng/mL (interquartile range 23–33 ng/mL) and there was no relationship between serum 25D and calcium absorption. Serum 25D increased with vitamin D3 dose (R2 = 0.50, p < 0.0001), but there was no relationship between increase in serum 25D and calcium absorption. There was no dose effect of vitamin D supplementation on calcium absorption before or after adjusting for pill compliance, race or sex. The results indicate that vitamin D supplementation is not necessary to increase calcium absorption in healthy early pubertal children living in diverse latitudes in the US during winter months.

Grant Funding Source: NIH grants HD057126 and RR025761
Bioavailability of folic acid and L‐5‐methyltetrahydrofolic acid in fortified bread: a randomized placebo‐controlled trial
Authors: Li Wangyang , Green Tim J , Kitts David D , Liu Yazheng , Böhni Ruth , Dadgar Samira
Published: June 2021

Folic acid fortification has been introduced in several countries to reduce the incidence of neural tube defects. However, it could mask the hematologic signs of vitamin B12 deficiency. L‐5‐methyltetrahydrofolic acid (MTHF), which is unlikely to mask vitamin B12 deficiency, may be a safer fortificant, but is not stable in most food matrices. Microencapsulation of MTHF with antioxidant sodium ascorbate is an effective means of preventing loss during baking and storage. The aim of the study was to investigate the bioavailability of microencapsulated MTHF in bread in a 16‐wk, double‐blind, randomized placebo trial. Healthy volunteers 18–45 y (n=45) were randomly assigned to bread containing MTHF (452 μg), folic acid (400 μg) or placebo. Fasting blood was analyzed for red cell and plasma folate concentrations at baseline, 8, and 16 wks. At 16 wk, after adjustment for baseline concentrations, mean (95% CI) red cell folate was 572 (341, 804) and 428 (200, 656) nmol/L higher in the MTHF (P<0.001) and folic acid (P=0.002) groups, respectively, than in the placebo group. Mean plasma folate was 28 (15, 41) and 26 (13, 39) nmol/L higher in the MTHF (P<0.001) and folic acid (P=0.01) groups, respectively, than in the placebo group. In conclusion, bread fortified with MTHF was at least as effective as folic acid in raising red cell and plasma folate concentrations in this population. (Supported by the Advanced Food Materials Network)
Individualized feedback during summer camp influences anthropometric changes in California's Central Valley overweight youth
Authors: George Gretchen Lynn , Schneider Constance , Martin Anna , Ginsburg David , Kaiser Lucia
Published: June 2021

The purpose of this study was to examine the effect of individualized feedback on cardiovascular risk factors in overweight youth (body mass index for age >; 85th percentile) within nutrition and physical activity themed camp. During summer 2012, 56 youth, 9–13 yrs, participated in a six week Healthy Lifestyle Fitness Camp (HLFC). The camp included 3 hours daily exercise and weekly nutrition lessons taught by UC CalFresh Nutrition Education Program. A randomly selected subgroup (HLFC+, n=11) wore accelerometer watches, provided diet information, and received individualized feedback pre, post and two month after camp. A control group (n = 30) was followed without exposure to HLFC. Trained staff measured the youths’ weights, heights, and waist circumferences. Significant differences were observed pre‐post camp in waist circumference to height ratio (WCHtR) between HLFC (‐0.03) and control (‐0.01) (t‐test, p=0.01). Greater WCHtR change was observed at two month in HLFC+ (‐0.06) compared to other HLFC campers (‐0.04) (t‐test, p=0.03). Nutrition and physical activity themed camps with individualized feedback may play a role in longer term risk reduction in overweight youth.