bluuebunny/crossref_metadata_2025 huggingface dataset:
A healthy‐lifestyles intervention improves children's diet quality in rural America
Authors: Cohen Juliana , Hyatt Raymond R. , Kraak Vivica I , Choumenkovitch Silvina F. , Economos Christina D
Published: June 2021

The objective of this study was to examine the impact of the CHANGE (Creating Healthy, Active and Nurturing Growing‐up Environments) study, a randomized, controlled, community‐based obesity prevention intervention in rural America, on the diets of participating elementary students (grades 1–6). Children's diets (n = 432) were assessed using the 2007 Block Food Screener in 8 rural schools and communities in California, Kentucky, Mississippi, and South Carolina. Changes in dietary intake were analyzed using mixed‐model analysis of variance, with schools included as a random effect nested within condition. At the end of one year, students in the intervention schools consumed significantly more vegetables (0.08cups/1000 kcal per day; p=0.03) and combined fruits and vegetables (0.22cups/1000 kcal per day; p=0.01) compared to students in control schools. Results were adjusted for corresponding baseline value, sex, age, grade, race/ethnicity, and state. Students enrolled in CHANGE Study intervention schools also showed a reduction in the average daily dietary glycemic index (GI −1.22; p=0.02). There were no significant differences in students’ consumption of whole grains, legumes, dairy, potatoes, saturated fat, added sugars, or dietary fiber. The CHANGE Study improved rural students’ diet quality, and was particularly promising as an intervention to support vegetable consumption.
Parathyroid Hormone (PTH) decreases mRNA stability of the Type IIa Sodium‐Phosphate Cotransporter (NpT2a)
Authors: Murray Rebecca , Lesousky Nina , Khundmiri Syed Jalal , Clark Barbara , Lederer Eleanor
Published: June 2021

In primary hyperparathyroidism, chronically elevated levels of PTH produce low serum phosphorus through inhibition of proximal tubule expression of sodium‐phosphate cotransporters. We have previously shown that chronic PTH stimulation of proximal tubule cells is associated with decreased expression of NpT2a mRNA through destabilization, which is dependent on transcription. BLAST evaluation of the NpT2a promoter identified a CREB‐binding region. We hypothesize that PTH decreases NpT2a mRNA stability through activation of the PKA pathway. Opossum kidney (OK) cells were transfected with luciferase reporter gene constructs containing either full‐length or serially truncated NpT2a promoter regions. Luciferase reporter assays show no effect of PTH on the promoter function of the NpT2a gene. Direct activation of PKA with 8Br‐cAMP and PKC with PMA for 2h produced a decrease in NpT2a mRNA of 35.6 ± 12.2% and 28.9 ± 4.3%, respectively. We conclude that PTH decreases NpT2a mRNA expression through destabilization of NpT2a mRNA, and that both PKA and PKC pathways may contribute to this effect. Support for this project is provided by VA to EDL.
Liver X Receptor activation inhibits intestinal phosphate transport
Authors: Jelen Sabina , Giral Hector , Caldas Yupanqui , Sutherland Eileen , Levi Moshe
Published: June 2021

Renal Pi reabsorption has been considered the main mechanism controlling Pi homeostasis. However, recently small intestine Pi absorption has emerged as a putative pharmacological target for the control of hyperphosphatemia, especially important in the setting of chronic kidney disease. We have recently reported that activation of Liver X Receptor (LXR) with LXR agonists leads to a decreased serum Pi concentration and increased urinary Pi excretion. In parallel, these changes were associated with the decrease of renal and intestinal NaPi transporters expression. To investigate the potential mechanisms behind this regulation we used two transgenic mouse models expressing: 1) constitutively active form of the LXRα fused with the activation domain of VP16 under LXRα endogenous promoter (VP16‐LXRα Tg); 2) enterocyte‐specific LXRα under villin promoter (villin VP16‐LXRα Tg).

VP16‐LXRα Tg and villin VP16‐LXRα Tg mice showed reduced sodium dependent Pi uptake in the brush border membrane (BBM) of enterocytes. This was accompanied by reduction of NaPi2b protein abundance in the BBM and also reduced ileum NaPi‐2b mRNA level.

Our results show that the effects of enterocyte‐specific activation of LXR are independent of systemic influences and also highlight importance of the intestine in Pi homeostasis regulation. However, the putative mechanisms of LXR effects on Pi transport remain to be elucidated

Supported by NIH
Urea channel Slc14a2 interactome in rat inner medullary collecting duct
Authors: Chou C.L. , Han L. , Pisitkun T. , Knepper M.A.
Published: June 2021

The urea channel Slc14a2 (or UT‐A) mediates vasopressin‐dependent urea transport across the inner medullary collecting duct (IMCD). To identify UT‐A1 interacting proteins in isolated IMCD suspensions, we employed crosslinking with BSOCOES, immunoprecipitation, SDS‐PAGE separation, and quantitative mass spectrometry (Velos‐Orbitrap) of trypsin digests of gel pieces (>;250 kD). The peptides passing stringent spectral quality thresholds were quantified (label‐free) to identify those with (UTA‐1 antibody/preimmune IgG) >;4. This identified a total of 1303 unique peptides matching to 120 proteins in the UT‐A1 interactome. Based on Gene Ontology analysis, these proteins are distributed throughout several intracellular compartments: endoplasmic reticulum, Golgi, endosomes, cytosol and plasma membrane. Among these proteins were four protein kinases (Phkb, Camk2d, Mtor, Cdc42bpb) that become candidates for roles in vasopressin‐regulated phosphorylation of UT‐A1. The results suggest that the UT‐A1 interactome consists of a series of dynamically related molecular complexes and provide a refined list of proteins that may regulate urea transport in IMCD.
SPAK's kinase activity and WNK4 expression are not essential for NCC activation under low K+ diet
Authors: Castaneda‐Bueno Maria , Cervantes‐Perez Luz Graciela , Gamba Gerardo
Published: June 2021

Modulation of NCC activity is an important mechanism for achieving the required levels of K+ excretion in the face of changes in dietary K+ intake. Here we used previously characterized genetic mouse models to assess the role of SPAK and WNK4 in the modulation of NCC by K+ diets. SPAK knockin (SPAK‐KI) mice, expressing a kinase inactive version of SPAK, and WNK4 knockout (WNK4‐KO) mice were placed on normal, high (HKD) or low K+ (LKD) diets for four days. Plasma aldosterone was altered by the diets as expected and the HKD induced the previously reported diuretic response. In wild‐type mice the LKD promoted a significant increase in phosphorylated NCC (pNCC; T58) and pSPAK/OSR1 (S383/S325). Interestingly, under LKD the increase in pNCC in SPAK‐KI mice and in pSPAK in the WNK4‐KO mice were also observed. In the WNK4‐KO mice, in which NCC expression is drastically reduced, no pNCC was observed under LKD and the animals developed severe hypokalemia. HKD induced an increase in pNCC, but not pSPAK. Thus, the diuretic response observed was not due to NCC inhibition and the increase in pNCC was SPAK‐independent, probably related to the increase in plasma aldosterone. In conclusion, SPAK's kinase activity and WNK4 are not essential for NCC activation under LKD. NCC is also activated under HKD, an effect that is not related to SPAK activation.
Generation of caveolin‐2 overexpressing C. elegans and their response to stress
Authors: Shi Eileen , Fridolfsson Heidi N. , Kwan Evan , Schilling Jan M. , Patel Hemal H.
Published: June 2021

The plasma membrane is a key barrier that impedes external stressors and responds to them by utilizing signaling microenvironments. Lipids rafts are cholesterol and glycosphingolipid enriched microenvironments containing scaffolding proteins— caveolins (Cav‐1, ‐2, ‐3 in mammals and Cav‐1, ‐2 in C. elegans) — that interact with and organize various signaling molecules. Increased caveolin expression in mice protects against cardiac and neuronal stress and limits age‐related dysfunction. This project seeks to analyze more global effects of caveolin by using C. elegans as a model species in which Cav‐2 is knocked out (KO) or overexpressed (OE), hypothesizing that overexpression will result in improved metabolic functions. KO's were provided whereas we generated Cav‐2 OE by inserting a let‐858 global promoter and Cav‐2 gene into a Mos‐II targeting vector. We observed significantly elevated (2‐fold) superoxide radical production in Cav‐2 KO, whereas Cav‐2 OE exhibited a 50% decrease relative to N2 controls in electron paramagnetic resonance. Cav‐2 KO also displayed significantly suppressed state‐3 generation of ATP, which was not observed in Cav‐2 OE relative to N2 wild‐type. We conclude that caveolin regulates mitochondrial stress in C. elegans, representing a potential therapeutic target in a wide range of diseases and disorders.
Prevalence of Gly482Ser polymorphism of PPARGC1A in Cuban Americans
Authors: Cheema Amanpreet K , Zarini Gustavo G , Vaccaro Joan A , Shaban Lemia , Dorak Mehmet T , Huffman Fatma G
Published: June 2021

Type 2 Diabetes (T2D) has grown to be a major public health issue worldwide. The fundamental clinical characteristic of T2D is high blood glucose levels which may be caused by anomalies in one or more different molecular pathways regulated by certain genes. The Gly482Ser polymorphism in human peroxisome proliferator‐activated receptor gamma coactivator‐1 alpha (PPARGC1A) has been associated with T2D. We genotyped Gly482Ser polymorphism in the PPARGC1A gene from 315 Cuban Americans (164 without T2D / 151 with T2D) using ABI TaqMan assays. Descriptive statistical analysis was performed using SPSS software. The genotype distribution for rs8192678 (Gly482Ser) polymorphism was found to be 0.42 for Gly/Gly, 0.47 for Gly/Ser and 0.10 for Ser/Ser with T2D and 0.47, 0.41 and 0.11 for Gly/Gly, Gly/Ser and Ser/Ser respectively without T2D. The findings in individuals without T2D demonstrate presence of homozygous genotype Gly/Gly to be highest. However, the prevalence of heterozygous genotype Gly/Ser was found to be relatively higher in individuals with T2D than without T2D. The clinical importance of the results has to be established in further studies. Funding was provided by an NIH grant.
Cardiac CARD9 mRNA expression in inbred rat strains divergent in survival time after severe hemorrhage (STaH)
Authors: Oh T. , Klemcke H.G.
Published: June 2021

We identified 3‐fold differences among inbred rat strains in STaH (Physiol Genomics 43: 758, 2011). We hypothesized that a protein of the caspase recruitment domain (CARD9) might be a specific cellular mediator associated with these differences. CARD9 is a known activator of nuclear factor κβ (JBC 275: 41082, 2000), a transcription factor that mediates both protective and detrimental effects on myocardial function (Clin Sci 118: 593, 2010). To test this hypothesis, we measured CARD9 mRNA levels using real‐time PCR in cardiac tissue in three inbred rat strains [Dark Agouti (DA), Fawn Hooded Hypertensive (FHH), and Brown Norway (BN)] divergent in STaH (DA = FHH >; BN). Rats from each strain were randomized to three treatment groups (n=5/group): controls without surgery (C); surgically catheterized rats (Cath); and catheterized and hemorrhaged rats (Bled). Surgeries were conducted ~ 24 hr prior to hemorrhage and tissue collections. Tissues were collected 30 min after start of a 26 min ~47% hemorrhage, or 30 min post handling in C and Cath rats. CARD9 mRNA was increased 3 to 25‐fold in DA vs BN or FHH rats (P < 0.01). Hemorrhage had no effect on CARD9 mRNA in any strain, but in DA CARD9 mRNA decreased in Cath vs C rats (P<0.05). These data indicate inbred rat strain‐dependent differences in cardiac CARD9 mRNA. High CARD9 mRNA in DA rats could influence cardiac responses to hemorrhage although not altered by hemorrhage itself.
Carbon Nanotube, Nanosilver and Nanoclay Protein Corona Composition in Cell Culture Media
Authors: Lai Xianyin , Shannahan Jonathan H. , Chen Ran , Ke Pu‐Chun , Mitra Somenath , Brown Jared M. , Witzmann Frank A.
Published: June 2021

During in vitro assessment of nanoparticle (NP) exposure in cell culture systems, NPs adsorb serum proteins in media to form a protein corona (PC). The composition of this PC may determine the nature of cellular interaction and biological effect. Using a label‐free quantitative mass spectrometry‐based proteomics approach, IdentiQuantXL, we examined the composition of the PC for various well‐characterized nanomaterials, including unmodified and carboxylated single‐(SWCNT) and multi‐walled carbon nanotubes (MWCNT), PVP‐coated MWCNT, nanoclay, and PVP‐and citrate‐coated silver nanoparticles. All nanotubes were found to associate with a common subset of 14 proteins and SWCNT‐COOH and MWCNT‐COOH were found to associate with the greatest number of proteins (181 and 133) compared to the unmodified nanotubes (<100). PVP or citrate capping did not significantly influence the protein types found in the AgNP PC, while comparison of AgNP and nanotube coronas revealed significantly different protein constituents and complexity. In conclusion, we observed differential protein corona composition based on functionalization, purity, and shape, which may influence the unique biological effects of these NPs in vitro.
HCN channels contribute to serotonergic modulation of chemoreceptors in the retrotrapezoid nucleus
Authors: Hawkins Virginia , Hawryluk Joanna , Takakura Ana , Williams Donny , Moreira Thaigo , Tzingounis Anastasios , Mulkey Daniel
Published: June 2021

Chemosensitive neurons in the retrotrapezoid nucleus (RTN) provide a CO2‐dependent drive to breathe, and function as a key locus of respiratory control by integrating information from several respiratory centers including the medullary raphe. Recent evidence showed that mechanisms underlying serotonergic modulation of RTN neurons involves inhibition of KCNQ channels and activation of an unknown inward current. Evidence also shows that RTN neurons produce a hyperpolarization‐activated inward current (Ih) at negative potentials. HCN channels are the molecular correlate of Ih and have a high propensity for neuromodulation. Therefore, we hypothesize that HCN channels contribute to serotonergic modulation of RTN neurons. We investigated this in vitro and in vivo using selective blockers for KCNQ (XE991) and HCN (ZD7288) channels. Membrane potential recordings in rat brain slices show that serotonin application increased chemoreceptor activity by ~1 Hz. Consistent with our previous evidence, XE991 decreased serotonin‐responsiveness by ~50%. The residual serotonin‐sensitivity in XE991 was blocked by ZD7288. In anesthetized rats RTN injection of XE991 blunted serotonin‐responsiveness and together XE991 and ZD7288 completely eliminated the respiratory response to serotonin. These results indicate that HCN channels contribute to serotonergic modulation of RTN chemoreceptors and respiratory drive. Funding sources: CURE Epilepsy Foundation (AVT, DKM), NIH HL104101 (DKM), NS073981 (AVT), and the Sao Paulo Research Foundation (FAPESP) (ACT, TSM).
IL‐22 increases CFTR expression and host defence capacity of airway epithelial cells
Authors: Cowley Elizabeth Asenath , Jones Christina , Li Tiesong
Published: June 2021

Interleukin (IL)‐22 is a pleiotropic cytokine which predominately targets epithelial cells. IL‐22 has been implicated in increasing epithelial host defence via a number of different mechanisms and we hypothesized its IL‐22 application would stimulate several protective mechanisms in airway epithelial cells. Using the model human airway bronchial epithelial cell line 16HBEo− we investigated the ability of IL‐22 to increase CFTR expression, and determined that treatment for 24 hours increased CFTR gene and protein expression, resulting in increased CFTR activity measured via iodide efflux assays. Furthermore, IL‐22 increased mRNA expression for the anti‐microbial peptides human beta‐defensin‐2 (hDB‐2) and neutrophil gelatinase‐associated lipocalin (NGAL), but had no effect on expression of the cathelicidin LL‐37. Additionally, we investigated the ability of IL‐22 to enhance epithelial repair using a mechanical wounding model, and determined that its presence significantly enhanced would healing in this model. IL‐22 application was associated with increased STAT‐3 phosphorylation. This is the first report of IL‐22 acting to increase CFTR expression and functionality, which together with its ability to increase anti‐microbial peptide expression and would healing ability, confirm its role as a potentially important factor in the airway epithelial host defence and repair. CFCanada and NSERC.
hCLCA1 Modulates Macrophage Activation
Authors: Ching John C.H. , Loewen Matthew E.
Published: June 2021

Induced by airway inflammation, the CLCA gene family products exist both as secreted and membrane‐associated proteins. The proteins modulate ion channel function, drive mucus production and generally have a pleotropic effect on airway inflammation. How CLCAs deliver such a pleotropic effect on airway inflammation is poorly understood. Here we show that hCLCA1, the primary up‐regulated human CLCA orthologue in airway inflammation, is able to modulate macrophage activation. In order for a macrophage to undertake a role of either host defense, wound healing or immune regulation, it must become “activated”. This is usually a receptor driven signal transduction event resulting in gene transcription of cytokines. Using primary porcine alveolar macrophages and the U‐937 macrophage cell model, we were able to show that conditioned media with hCLCA1 significantly increased macrophage activation over control. The pro‐inflammatory cytokines IL‐1beta, IL‐6, TNF‐alpha, IL‐8 were increased, and the anti‐inflammatory cytokine IL‐10 was decreased in the U‐937 cell line. We found this effect to be independent of hCLCA1's metalloprotease domain. Subsequent purification of hCLCA1 produced a similar response demonstrating that the effect is primarily due to hCLCA1. These are the first findings demonstrating that hCLCA1 can deliver an immune modulating effect as a signaling molecule. Funding: SHRF, EHRF and NSERC
Phosphorylation of Kv7 potassium channels by protein kinase C in human airway smooth muscle cells
Authors: Haick Jennifer M , Brueggemann Lioubov I , Prochot Jeffrey R , Randhawa Devjit S , Wigfield Christopher , Byron Kenneth L
Published: June 2021

In previous studies, bronchoconstrictor agonists inhibited Kv7 potassium currents in guinea pig airway smooth muscle cells (ASMCs) and the selective Kv7 channel blocker XE991 induced severe bronchoconstriction in human precision cut lung slices (PCLS). However, the mechanism of regulation of airway Kv7 channels is unknown. In the present study, we investigated protein kinase C (PKC)‐induced phosphorylation and inhibition of Kv7 channels. The ability of PKC activator phorbol 12‐myristate 13‐acetate (PMA) to induce bronchoconstriction was examined using human PCLS. We found that PMA induced robust constriction of human airways. Immunoprecipitation and western blot analysis were used to detect phosphorylation of Kv7.5 channels in response to histamine or PMA using human trachealis smooth muscle cells (HTSMCs) infected with a FLAG‐tagged human Kv7.5 adenoviral vector. Both treatments caused increased FLAG‐Kv7.5 phosphorylation. Histamine inhibited Kv7.5 currents in HTSMCs but that effect was abolished when cells were pretreated with the PKC inhibitor calphostin C. Our findings suggest a role of PKC‐induced phosphorylation in the suppression of Kv7 channels in ASMCs. (Funded by Loyola University Chicago.)
Hydrogen sulfide induces smooth muscle relaxation in small intrapulmonary airways
Authors: Castro‐Piedras Isabel , Perez‐Zoghbi Jose F
Published: June 2021

Hydrogen sulfide (H2S) has been recognized recently as a gaseous signaling molecule that has a variety of physiological functions. However, the role of H2S in the respiratory system is not fully understood. We used mouse lung slices to study the effect of H2S on airway smooth muscle contraction. Perfusion of lung slices with 100 μM Na2S (a H2S donor) induced ~60% relaxation of airways pre‐contracted with 100 nM ACh. A similar H2S‐induced relaxation was observed in airways pre‐contracted with 5‐HT. H2S‐induced relaxation was sustained, reversible, and concentration‐dependent. Furthermore, H2S right‐shifted the ACh concentration‐contraction curve and decreased the maximal airway contraction. Similar to H2S, addition of 10 mM L‐cysteine (Cys) –a precursor of the H2S biosynthesis, strongly relaxed ACh‐contracted airways. In contrast, 10 mM L‐serine induced small airway relaxation. Furthermore, Cys‐induced airway relaxation was inhibited by propargylglycine (PPG), an inhibitor of the H2S synthesizing enzyme cystathionine γ‐lyase (CSE). The mechanism of H2S‐induced airway relaxation is currently being investigated. In conclusion, H2S has bronchodilator properties by inducing strong relaxation in small airways. Supported by the American Lung Association & American Heart Association.
Local delivery of endothelial cell spheroids to promote angiogenesis through novel extracellular matrix mimicking electrospun scaffolds
Authors: Nosoudi Nasim , Yin Wei , Rubenstein David Alan
Published: June 2021

Electrospinning has become a prominent process for fabricating nano‐ to micro‐scale fiber scaffolds for a tissue engineered extracellular matrix (ECM). We have shown that a scaffold formed from blended ethylene‐co‐acrylic acid, polycaprolactone, polyethyleneoxide, polyethylenegycol and powdered milk is compatible with endothelial cells (ECs), supports EC communication and promotes rapid new network growth. Here we aimed to test whether the addition of methylcellulose, a polymer known to enhance EC adhesion, in leiu of powdered milk, can accelerate new network growth from EC spheroids, a pro‐angiogenic cell source. In vitro cytotoxicity testing, conducted with a LDH assay, a MTT assay and a cytotoxicity assay, showed that scaffolds were compatible with and support spheroid growth. VEGF concentration and connexin‐43, caveolin‐1 and VEGFR1 expression were quantified and showed that stable communicative sprouts formed throughout scaffolds and that this was likely mediated by an increased VEGF concentration. We conclude that our novel scaffold is desirable for microvascular tissue engineering and that EC spheroids are viable to promote angiogenesis throughout ECM mimicking scaffolds. Thanks to the NIH.
Prediction of Optimal Continuous‐Flow Total Artificial Heart and Vascular Parameters to Maintain Hemodynamic Homeostasis
Authors: McDowall Michael T. , Adair Paige A. , Knezek Sarah F. , Tuzun Egemen , Quick Christopher M.
Published: June 2021

Ventricular‐vascular interaction is very complex, because pulsatile pressures depend on vascular properties and three cardiac parameters—heart rate, ventricular compliance and contractility. There is a growing interest in modeling the interaction of the vasculature and continuous‐flow pumps to optimize the design, control, and pharmacological support of a continuous‐flow total artificial heart. The lack of pulsatility that makes the interaction easier to model, however, also introduces a new constraint: continuous‐flow pumps depend only on two parameters—pump speed and an internal resistance. The purpose of this work is to predict flows and pressures in terms of vascular and pump properties. The vasculature was characterized by parameters for arterial and venous compliances, as well as systemic and pulmonary resistances. Through linearization and simplification, we were able to develop simple algebraic formulas predicting total flow, systemic arterial and venous pressure, pulmonary arterial and venous pressure, as well as pump power. With fewer parameters than a ventricle, a pump does not have enough flexibility to adjust the limited set of pump parameters to independently control pressures while maintaining normal blood volume and vascular resistances. Our algebraic solution, however, suggests that pump and vascular parameter values can be adjusted to optimize hemodynamic homeostasis.
CelluCCCClar changes in human tendon cells as a result to release of mechanical tension
Authors: Bayer Monika Lucia , Schjerling Peter , Heinemeier Katja Maria , Gullberg Donald , Herchenhan Andreas , Krogsgaard Michael , Kjaer Michael
Published: June 2021

The objective was to study the effect of tension release on human tendon cell gene expression and cell‐matrix interaction. Tendon cells in healthy tendon are subjected to tensile load, but in injured tendon, this stimulus is disrupted. This might lead to substantial cellular changes and alterations in cell‐matrix interactions, thereby complicating healing. Differentiated tendon cells express scleraxis, tenomodulin (Tnm), Mohawk homeobox (Mkx) and several matrix proteins, and tendon cells bind to the matrix through integrins. We hypothesized that tension release will lead to a downregulation of tendon‐specific genes and a decline of proteins by which cells interact with the matrix. Tendon‐like tissue was engineered with human tendon cells and cultured under static load or in the absence of load. Samples were collected 6 days post tension release and analyzed for gene and protein expression. Release of tension reduced gene expression of Tnm, Mkx, collagen type I, III, XII and XIV and decorin (p< 0.05) and preliminary results show decreased protein levels of the collagen receptor integrin α11. The study emphasizes the importance of tensile load on cell differentiation and formation of cell‐matrix contacts. The de‐coupling of cell‐matrix interactions might be a crucial factor in tissue injury and regeneration.

Research was supported by the Danish Medical Research Council, the Nordea Foundation and Lundbeck foundation.
The prognostic value of nonlinear indices of blood pressure variability in mouse models of sepsis
Authors: Vandendriessche Benjamin H , Rogge Elke , Brouckaert Peter , Cauwels Anje
Published: June 2021

Sepsis is associated with high mortality despite decades of research. A lack of validated biomarkers prevents the extrapolation of experimental data to the clinic. It has been well established that the sympathetic/parasympathetic balance is altered in critically ill patients, and that assessment of autonomic function has prognostic value that can be used to direct treatment.

We used implantable telemetry devices to monitor blood pressure (BP) in conscious mice and developed a system in Matlab that implements a number of analysis algorithms, including multiscale entropy (MSE). These algorithms model the dataset as a nonlinear system and are capable of uncovering underlying regulating patterns. This approach allows us to do semiautomatic analysis of large amounts of data. In order to overcome the fact that interpretation of MSE results is time consuming, we developed a scoring algorithm that summarizes the output in a single numerical value, which can be plotted in function of time to follow disease progression.

As proof of principle, BP measurements from mice that received a lethal or sublethal dose of TNF (tumor necrosis factor), a simple model for inflammatory shock, were analyzed. We found that the MSE parameter can distinguish between lethal/non‐lethal outcome already in the first 2 hours post‐TNF. Preliminary data indicates that this observation can be expanded towards other sepsis models and ICU patients.
Fabrication of Three dimensional porous matrix and bone tissue regeneration
Authors: Zo Sunmi , Singh Deepti , Lee Juhyun , Ki Saetbyul , Han Sungsoo
Published: June 2021

Ideal scaffold for tissue engineering are often tailor‐made to mimic the micro‐environment and have to act similar to the extracellular matrix of the tissue which has very defined role such as to provide appropriate structural, chemical and mechanical support. The fabrication of three‐dimensional (3‐D) scaffold with highly open porous structure is one of the most important issues in tissue engineering. The aim of the study was to demonstrate potentiality of 3‐D macroporous scaffolds in bone tissue engineering. Scaffold was synthesized with varying pore morphology by freeze‐drying the polymer solution and chemically crosslinking by using CaCl2. The resulting scaffolds were characterized by SEM, tensile strength, and DSC. The biocompatibility and bioactivity were evaluated using differentiation of mesenchymal stem cells into osteoblasts MTT assay, ALP activity, ALP stain test. DNA measurement showed that the differentiated osteoblasts multiplied into several layers on three dimensional porous matrix. Histological analysis for in vivo biocompatibility were performed. The in vitro analysis of the scaffold showed excellent for cell penetration, growth and it is promising for bone repair application.

Powered by
Intracellular proteases and sarcomere disassembly in neonatal cardiomyocytes
Authors: Fan Frank (Xiaohu) , Ali Mohammad A.M. , Lopez Waleska , Kondo Marcia Y. , Hughes Bryan G. , Schulz Richard
Published: June 2021

Mammals lose the capacity to regenerate their hearts shortly after birth. Although it is known that neonatal cardiomyocytes need to undergo sarcomere disassemble for cytokinesis, the mechanism of this is unclear. We studied this in neonatal rat ventricular myocytes (NRVM). We performed immunofluorescence studies of multiple sarcomeric proteins in proliferating NRVM using confocal microscopy and time lapse imaging. We also developed a fluorescence activated cell sorting (FACS)‐based method to separate NRVM in different cell cycle stages. During NRVM division α‐actinin, troponin I and titin were completely disassembled. Both Z‐disk and M‐band ends of titin disassemble simultaneously. Interestingly, sarcomere disassembly begins promptly at late prophase, at the same time when the nuclear envelope breaks down. Reassembly of the myofibril starts when the nuclear envelope re‐forms. Western blot from cells separated into G0G1, S and G2M phases revealed that α‐actinin, troponin I and myosin binding protein C were most prominently degraded in the G2M phase. Live cell imaging of NRVM expressing Halo‐ tagged matrix metalloproteinase‐2 revealed a strong signal inside nuclei which is released into the cytosol when the nuclear envelope breaks down. This study suggests that a protease regulated in a precisely timed manner may be involved in the disassembly of the sarcomere during mitosis.
Myocardial injection with apelin‐overexpressing bone marrow cells improves cardiac repair and systolic function after myocardial infarction
Authors: Chen Jian‐Xiong , Li lanfang , Zeng heng
Published: June 2021

Our study showed that apelin increases vascular progenitor cell recruitment and promotes cardiac repair after myocardial infarction (MI). However, the effect of apelin on bone marrow cells (BMCs) therapy after MI remains unknown. To investigate whether overexpression of apelin in BMCs improves cell therapy and accelerates cardiac repair and systolic functional recovery in post‐ MI mice. Mouse MI was achieved by coronary artery ligation and BMCs overexpressing apelin (apelin‐BMCs), GFP (GFP‐BMCs) or saline were injected into ischemic area immediately after MI. Apelin receptor (APJ+)/c‐kit+/Sca1+ cells, sirtuin3 (Sirt3) expression and reactive oxygen species (ROS) were assessed. Intramyocardial delivery of apelin‐BMCs led to a significant increase in APJ+/c‐kit+/Sca1+ cells in ischemic area compared to GFP‐BMCs or saline‐treated mice. Apelin‐BMCs treatment led to a significant increase in Sirt3 expression and suppression of ROS formation. Apelin‐BMCs treatment significantly increased angiogenesis and attenuated cardiac scar formation in post‐MI. Most importantly, treatment with apelin‐BMCs significantly improved left ventricular (LV) systolic function, whereas knockout of Sirt3 blunted apelin‐BMCs‐mediated improvement of cardiac repair and systolic functional recovery. Apelin may increase number of APJ+/c‐kit+/Sca1+ cells and improve BMCs therapy after MI via upregulation of Sirt3.
Canadians are concerned about dietary sodium, report barriers to sodium reduction, and highly support government interventions to lower sodium intakes: Results of a national survey
Authors: Arcand JoAnne , Mendoza Julio , Qi Ying , Henson Spencer , Lou Wendy , L'Abbe Mary R
Published: June 2021

Population‐wide dietary sodium reduction is considered a priority intervention to address sodium‐related chronic diseases. In Canada, a national Sodium Reduction Strategy was adopted in 2010; however, there has been a lack of coordinated action in its implementation. We conducted a survey of Canadians (20–69 yrs) to evaluate concern, action, barriers to sodium reduction, and support for government policy interventions. Of the 2603 respondents, 67.2% were concerned about dietary sodium, which increased with age (p<0.001), among men (p=0.012), and in hypertensives (p<0.001). In total, 59.0% were actively limiting their sodium consumption, which was more common in older people (p<0.001) and in hypertensives (p<0.001). Significant barriers to sodium reduction were lack of variety of lower sodium processed (55.5%) and restaurant (65.8%) foods. Respondents highly supported government actions to lower sodium levels in processed foods (86.6%), to set maximum sodium levels for foods served in public institutions (81.8% to 82.3%), and for public education interventions (80.4% to 83.1%); but not financial incentives and disincentives for high/low sodium foods. Based on Canadians’ concern and support for population‐wide sodium reduction, there is a need for multi‐sectoral action to aid Canadians in lowering their sodium intakes to levels consistent with dietary recommendations.

Grant Funding Source: Canadian Institute for Health Research
Absorption, distribution, metabolism and elimination of a stable isotope‐labelled anthocyanin in Humans
Authors: Kay Colin D. , Botting Nigel P. , Cassidy Aedin , Czank Charles , de Ferrars Rachel , Kroon Paul A. , Morrison Douglas J. , Preston Tom , Zang Qingzhi
Published: June 2021

Evidence suggests anthocyanins beneficially affect cardiovascular health; yet their absorption, distribution, metabolism and elimination (ADME) is poorly understood. We characterised the ADME of a13C‐labeled anthocyanin in humans. 8 male participants consumed 500 mg of labeled cyanidin‐3‐glucoside. Serum, urine, feces and breath collected over 48 h were analysed using isotoperatio mass spectrometry and liquid chromatography‐tandem mass spectrometry. 43.9 ± 25.9% of 13C was recovered in the urine, breath and feces, with a calculated relative bioavailability of 12.3 ± 1.3%. Metabolites were identified as degradation products (protocatechuic acid and phloroglucinaldehyde), phenolic, hippuric, phenylacetic and phenylpropenoic acids. Maximum rates of 13C absorption were achieved 30 min post ingestion (32.5 ± 14.2 μg/mL/h), while 13C‐labeled metabolites collectively peaked (6.0 ± 2.1 μmol/L) in the serum at 10.2 ± 4.1 h; with the total phase II conjugates of protocatechuic acid reaching 2.3 ± 0.1 μmol/L at 13.4 ± 2.5 h. The half‐lives for metabolites ranged between 12.4 ± 4.2 h for the phenolic degradation products to 51.6 ± 22.5 h for ferulic acid. Our data suggest that anthocyanins are more bioavailable than previously perceived and their metabolites are still present in the circulation after 48 h. Research support: UK Biotechnology and Biological Sciences Research Council (BBSRC‐DRINC; BB/H004963/1).
Establishing and maintaining the complex adhesions of the testes: a role for the omega‐3 DHA
Authors: Abbott Timothy L , Hess Rex A. , Sivaguru Mayandi , Nakamura Manabu T.
Published: June 2021

Spermatid maturation and retention in the testis depend on the establishment and maintenance of a cell adhesion complex formed between spermatids and Sertoli cells. Deficiency in docosahexaenoic acid (DHA) was recently shown to disrupt postmeiotic germ cell maturation and result in infertility; however a role for DHA in germ cell adhesion has yet to be defined. Here, we use Fads2−/− mice to investigate the effect of a DHA deficiency on this adhesion process. We show impaired retention of immature spermatids in the seminiferous epithelium and their abnormal appearance in the nearest distal tissue, the epididymis. With immunohistochemistry we show that an essential adhesion protein expressed in spermatids (nectin‐3), and its binding partner in Sertoli cells (nectin‐2), each fail to organize at the sites of spermatid‐Sertoli contact, whereas both proteins organize normally in other regions of these cells. Further, vesicular transport proteins golgin‐97 and VAMP4, normally redistributed to the spermatid‐Sertoli adhesion at the initiation of its assembly, failed to do so under a DHA deficiency. In conclusion, spermatid retention is impaired under DHA deficiency due to a failure of spermatid‐Sertoli adhesion construction; the selective mislocalization of nectin‐2 and nectin‐3 suggests a role for DHA in certain specialized systems of complex adhesion assembly.

Grant Funding Source: Hatch project ILLU‐971–354 through the Division of Nutritional Sciences Vision 20/20 program
Microbiota‐Dependent Th17 and Foxp3+ Regulatory T Cell Differentiation in the Intestinal Lamina Propria
Authors: Geem Duke , Medina‐Contreras Oscar , Newberry Rodney , Denning Timothy Luke
Published: June 2021

The intestinal microbiota regulates the development and function of mucosal and systemic immune responses. Segmented filamentous bacteria (SFB) and Clostridium strains have been implicated in the development of intestinal Th17 cells and Foxp3+ regulatory T (Treg) cells, respectively, yet the mechanisms and location of their differentiation remains incompletely understood. Using lymphotoxin‐alpha knockout mice, which are deficient in secondary lymphoid organs (SLO)‐including gut‐associated lymphoid structures, we examined the influence of the microbiota on CD4+ T cell differentiation directly in the intestinal lamina propria. Our data demonstrate that CD4 single‐positive thymocytes adoptively transferred into congenic recipients were capable of rapidly migrating to the intestinal lamina propria. Consistent with these observations, naïve CD4+ T cells were abundant in the intestines of both adult gnotobiotic mice and early postnatal SPF mice, and bacterial colonization of either group induced differentiation of Foxp3+ Treg cells, as detected by flow cytometry. Oral gavage of SFB‐containing microbiota into SFB‐free mice was also sufficient to drive Th17 differentiation in mice void of SLO. Collectively, these data suggest that specific components of the microbiota are capable of inducing the development of effector and regulatory T cell subsets directly in the intestinal lamina propria.

Supported by an Emory Children's Pediatric Center Seed Grant to T.L.D. a Research Fellowship Award from the Crohn's and Colitis Foundation of America to O.M.C. and a F30 NIH NRSA Fellowship to D.G.
Symbiotic Lactobacilli Stimulate Metazoan Gut Proliferation via Induction of Reactive Oxygen Species by Nox1
Authors: Jones Rheinallt , Alam Ashfaqul , Luo Liping , Ardita Courtney S , Neish Andrew S
Published: June 2021

It is well established that physiological generation of low levels of ROS act as critical second messengers in multiple signaling pathways. These include the regulatory networks that control growth and differentiation in disparate biological systems, including the gut of many metazoans. However, the molecular mechanism of ROS production within the intestine is unknown. Recent reports have shown that the ROS‐generating enzyme NADPH oxidase 1 (Nox1) is highly expressed by colon epithelia. We report that Lactobacillus spp. are potent inducers of endogenous ROS generation, and of ROS‐dependent cellular proliferation within intestines of two metazoan models, namely the fruitfly Drosophila melanogaster, and the mouse. Moreover, we show that these induced responses are diminished in mice or Drosophila that are selectively deficient for Nox1 within intestinal epithelial cells. Together, these results implicate Nox1 in epithelial cell homeostasis and reveal a novel mechanism for the maintenance of intestinal tissue structure.
An extracellular matrix‐based mechanism of rapid neutrophil extracellular trap formation in response to C. albicans
Authors: Byrd Angel S. , O'Brien Xian M. , Johnson Courtney M. , Lavigne Liz M. , Reichner Jonathan S.
Published: June 2021

The armament of neutrophil‐mediated host defense against pathogens includes the extrusion of a lattice of DNA and microbicidal enzymes known as Neutrophil Extracellular Traps (NETs). The receptor:ligand interactions and intracellular signaling mechanisms responsible for elaborating NETs were determined for the response to Candida albicans. Since the host response of extravasated neutrophils to mycotic infections within tissues necessitates contact with ECM, this study also identified a novel and significant regulatory role for the ubiquitous matrix component fibronectin (Fn) in NET release. We report that recognition of purified fungal pathogen‐associated molecular pattern β‐glucan by human neutrophils causes rapid (≤ 30 mins) homotypic aggregation and NET release by a mechanism that requires Fn. Alone, immobilized β‐glucan induces reactive oxygen species (ROS) production but not NET release, whereas in the context of Fn, ROS production is suppressed and NETs are extruded. NET release to Fn+ β‐glucan is robust, accounting for 17.2 ± 3.4% of the total DNA in the cell population. Release is dependent on β‐ glucan recognition by CR3 (CD11b/CD18), but not Dectin‐1, or ROS. The process of NET release included filling of intracellular vesicles with nuclear material that was eventually extruded. We identify a role for ERK in homotypic aggregation and NET release. NET formation to C. albicans hyphae was also found to depend on β‐glucan recognition by CR3, require Fn and ERK but not ROS and result in hyphal destruction. In a recent study, there was NET extrusion from neonatal PMNs in response to immobilized Fn + β‐ glucan, but not when stimulated with PMA. We report a new regulatory mechanism of NETosis in which the extracellular matrix is a key component of the rapid anti‐fungal response.
MicroRNA‐155 plays an important role in endothelial cell activation
Authors: Virtue Anthony , Wang Hong , Yang Xiao‐feng
Published: June 2021

Within a pro‐inflammatory environment, the physiological characteristics of endothelial cells are altered leading to the production of cytokines and chemokines as well as the upregulation of adhesion molecules. These changes collectively referred to as endothelial activation, aid in leukocyte attraction, adherence, and diapedesis. Previously we have identified a group of anti‐atherogenic microRNAs that may play a critical role in suppressing the expression of pro‐atherogenic inflammatory genes, however, microRNA regulation of endothelial cell activation remains poorly characterized. To address this, our research focuses on whether the expression of the pro‐inflammatory microRNA, miR‐155, affects endothelial activation. Thus far, we have identified several known endothelial activators such as, bacterial endotoxin lipopolysaccharide, tumor necrosis factor‐α (TNF‐α), and interleukin‐1β (IL‐1β) that augment miR‐155 expression. This suggests that Toll‐like receptor/IL‐1 receptor and TNF receptor pathways induce the up‐regulation of miR‐155 in endothelial cells. Furthermore, we have determined that monocyte adhesion to transfected endothelial cells is altered with miR‐155 expression. Mechanistically, in agreement with these results, we have also found that the expressions of adhesion molecules are differentially regulated by miR‐155 expression. These findings suggest that miR‐155 plays a major role in endothelial activation, and therefore restraint of miR‐155 expression holds significant therapeutic potential in the treatment of cardiovascular diseases.
IFN‐γ‐mediated Induction of an Apical IL‐10 Receptor on Polarized Intestinal Epithelia
Authors: Kominsky Douglas J , Campbell Eric L , Kelly Caleb J , Glover Louise E , Bowers Brittelle E , Bayless Amanda J , Dobrinskikh Evgenia , Ehrentraut Stefan F , Colgan Sean P
Published: June 2021

OBJECTIVE

Investigation of potential anti‐inflammatory mechanisms of IFN‐ in intestinal epithelial cells (IEC) in models of inflammatory bowel disease (IBD).

METHODS

Guided by microarray analysis, we utilized qPCR, western blot, and confocal microscopy to characterize epithelial IL‐10 receptor (IL‐10R) expression in vitro. Next, the functional consequences of receptor expression were examined. Finally, IL‐10R expression was investigated in a murine IBD model and in human IBD patient samples.

RESULTS

In vitro studies revealed that IFN‐ selectively induced the expression of IL‐10R1 on IEC. Further analysis revealed that IL‐10R1 was expressed predominantly on the apical membrane of polarized IEC. Receptor activation functionally induced canonical IL‐10 target gene expression in IEC, concomitant with enhanced barrier restitution. Colonic tissue isolated from murine colitis revealed that levels of IL‐10R1 and SOCS3 were increased in the epithelium and coincided with increased tissue IFN‐ and IL‐10 cytokines. Immunofluorescent staining revealed apical expression of the IL‐10R in colitic mouse tissue. Finally, diseased human tissue demonstrated increased IL‐10R1 transcript with apical IEC localization.

CONCLUSIONS

These results provide novel insight into an anti‐inflammatory role for IFN‐ in intestinal inflammation through the induction of a polarized IL‐10 receptor complex.
Fut3‐driven expression of Sialyl Lewis A on intestinal epithelium regulates PMN clearance
Authors: Brazil Jennifer , Liu R , Cummings R. D , Parkos C. A , Louis N. A
Published: June 2021

Sialic acids are common in vertebrate surface glycans where they contribute to markers of self, regulating host immune responses. Pathogen‐triggered neutrophil (PMN) recruitment is critical for innate immunity, but aberrant PMN accumulation within intestinal crypts marks disease severity in inflammatory bowel disease (IBD). Using a novel mAb GM35, we identified the tetrasaccharide epitope, sialyl Lewis a (sLea) as the terminal structure in an inflammation‐dependent O‐glycan presented on intestinal epithelial cells (IECs). sLea displayed by CD44v6 regulates PMN transepithelial migration (TEM) through limiting CD44v6 cleavage. Both sLea and CD44v6 are expressed only in inflamed mucosa. Immunoblotting and mass spectrometric analyses of human IECs also revealed cell‐specific differences in the presentation of other glycoepitopes. IEC lines with differing sLea expression were employed to investigate mechanisms governing its synthesis. Real time PCR screening of glycosylating enzymes identified α3/4 fucosyltransferase3 (Fut3) as a candidate regulator of these cell‐specific differences. Thus, we have characterized novel differences in the O‐ and N‐glycan expression of specific glycoepitopes and further demonstrated Fut3‐driven expression of sLea as an important mechanism regulating PMN TEM in inflamed intestine. Pharmacologic targeting of glycan expression may lead to novel therapies for IBD.