bluuebunny/crossref_metadata_2025 huggingface dataset:
MCP‐1 −/− Mice Show Blunted Inflammatory Cytokine Response and Improved Recovery Following Exercise‐Induced Muscle Damage
Authors: Gordon Benjamin Thomas , McClellan Jamie , Murphy E. Angela , Carmichael Martin D. , Davis J. Mark
Published: June 2021

The body's inflammatory response to eccentric‐biased exercise in both brain and muscle contributes to impaired performance recovery. Monocyte chemoattractant protein (MCP‐1) is essential in the release of inflammatory mediators, but its role in exercise‐induced muscle damage has not yet been determined. The purpose of this study was to determine the role of MCP‐1 on brain and muscle inflammation following a novel bout of downhill running. C57BL/6 (n=24) and MCP‐1−/− mice (n=24), 8 weeks of age were randomly assigned to one of six groups: downhill runner wild type (DH‐WT), uphill runner wild type (UH‐WT), sedentary wild type (WT), downhill runner MCP‐1−/− (DH‐MCP‐1−/−), uphill runner MCP‐1−/− (UH‐MCP‐1−/−), and sedentary MCP‐1−/− (MCP‐1−/−). The mice were run on a treadmill at −/+14% grade and 22m/min, for 150 min. Mice were sacrificed at 24h post downhill run, and the brain and gastrocnemius muscle (G) were dissected and analyzed for IL‐1β, IL‐6, TNF‐α and F4/80 mRNA using RT‐PCR. Gene expression of IL‐1β, IL‐6 and TNF‐α was increased in the cerebellum, cortex and G in DH‐WT relative to WT (p<0.05), whereas DH‐MCP‐1−/− was not different from WT. A similar effect was observed for F4/80 but this reached statistical significance in G only (p<0.05). No differences were found in any other groups. These data support a necessary role for MCP‐1 following exercise‐induced muscle damage.

Supported by a grant from NASA and ACSM.
The effects of consuming egg‐based versus bagel‐based breakfasts combined with resistance training on body composition and muscular strength
Authors: Hernandez Lisa M. , Hobb Kylee , Clayton Zachary , Shelechi Mahshid , Barber Anjee , Petrisko Yumi , Hooshmand Shirin , Kern Mark
Published: June 2021

Research has demonstrated that protein supplementation in combination with a regular resistance exercise program may improve body composition in adults by increasing lean body mass (LBM) and reducing fat mass (FM) and percent body fat (PBF). The purpose of this study was to determine if daily intake of two eggs/day as part of breakfast (EBB: 43% CHO; 25% protein; 32% fat) would enhance LBM accretion and strength when combined with resistance training (three times/week before breakfast) in comparison to a bagel‐based breakfast (BBB: 68% CHO; 17% protein; 15% fat) matched for energy content (~400kcal). Twenty‐six adult men and women (18–35 years old) participated in the randomized 12‐week study. Body composition was assessed by Bod Pod every 6 weeks and strength every 3 weeks. After 12 weeks, preliminary results suggest that LBM tended to increase within both groups, but no statistical differences were detected within or between groups. Squat 1RM increased (p<.05) for EBB (94%) and BBB (87%). Bench press 1RM increased for EBB (32%) and BBB (61%), but greater increases (p<.05) were detected for EBB. These data preliminarily suggest that when combined with regular resistance training exercise, consuming an EBB or BBB similarly influence body composition and that an EBB may offer a modest advantage for some measures of strength. Supported by the Egg Nutrition Center.
The effect of cotton and dry wicking materials on temperature, exertion, and feeling during exercise
Authors: Norkett Kelsey , Vick Robert
Published: June 2021

This study analyzed the thermoregulatory effects of cotton and dry wicking materials during strenuous exercise. The working hypothesis is that dry wicking shirts will keep the participant cooler and possibly allow a better athletic performance. 11 healthy and euhydrated participants (8 females, avg age=20.5 ± 0.7 yr, 3 males, avg age=29 ± 14.1yr) ran on a treadmill for 45 min in a controlled environment (Temp=70 ±1°F, RH=60.5 ±3.5%) at 75% VO2 max. The participants ran 1 trial each in a randomly assigned a long sleeve cotton (COT) or polyester/nylon (PN) shirt. Data was taken every 10 min for 40 min, with a 5 min cool down. No significant difference was observed in hydration level or self‐reported thermal sensation. Core temperature was significantly higher in PN (p≤0.07) except at time=0 and 30 min. Forearm and forehead temperature were significantly higher in PN (p≤0.07) at time ≥ 20 min. Rating of Perceived Exertion was significantly higher with COT (p≤0.07) and Feelings Scale ratings were significantly lower with COT (p≤0.08) at every time point. In conclusion, under identical exertion, participants wearing PN shirts had more positive exercise experience, and dissipated more heat. Our data supports our working hypothesis. Funding provided by Elon University Undergraduate Research Program
Air Displacement Plethysmography Weakly Predicts Changes in Percent Body Fat in Comparison to Dual X‐ray Absorptiometry After Aerobic Exercise Training in Women
Authors: Bhammar Dharini , Sawyer Brandon , Angadi Siddhartha , Ryder Justin , Ryan Dana , Gaesser Glenn
Published: June 2021

We determined whether changes in body fat after aerobic exercise training in women could be tracked equally well by air displacement plethysmography (ADP) in comparison to Dual X‐ray Absorptiometry (DXA). Seventy‐three healthy non‐vigorously active females (age: 30.5 ± 7.9 yrs; ht: 164.7 ± 7.5 cm; wt: 67.2 ± 14.4 kg; %fat: 37.5 ± 8.7%) had body fat assessed by ADP and DXA before and after a 12‐wk exercise program of treadmill walking 3 days/wk for 30 min at 70% of VO2max. Overall, ADP underestimated %fat compared to DXA (31.9 ± 8.5% vs. 37.3 ± 8.6%; P < 0.001). Bland‐Altman analysis revealed a considerably wide limit of agreement in %fat at baseline (Mean difference = 6.5 %fat; 95% CI: −15.2 to +2.2) and at 12 weeks (Mean difference = 5.2 %fat; 95% CI: −11.8 to +1.4). There was a reduction in %fat DXA after 12 weeks of training (− 0.5 ± 1.9 %; Range: −8.8% to +2.4%; P = 0.019) but not in %fat ADP (−0.9 ± 4.3%; Range: − 18.7% to +11.3%; P = 0.09). DXA and ADP were strongly correlated at baseline (r = 0.873; P < 0.001) and after 12 weeks of training (r = 0.923; P < 0.001). However, Δ %fat values (12 weeks – baseline) for ADP and DXA were only weakly correlated (r = .321; P = 0.006). Although ADP may be suitable for assessing %fat at discrete time points, ADP may not be reliable for tracking changes in percent body fat in females after aerobic exercise training that produces negligible mean fat loss despite considerable between‐subject variation in %fat changes.
Multiple‐staged Regulation of Myogenic Differentiation by Prostaglandin E2
Authors: Mo Chenglin , Romero-Suarez Sandra , Igwe Orisa , Brotto Marco
Published: June 2021

We showed that conditioned media from osteocytes accelerates myogenesis in C2C12 myoblasts, which suggests signaling from bone to muscle cells. Since osteocytes secrete Prostaglandin E2 (PGE2), one of the major PGs synthesized from arachidonic acid through cyclooxygenase pathways, we started a systematic investigation of PGE2 roles in myogenesis. C2C12 myoblasts were used to investigate the effect and related molecular mechanisms of PGE2 on myogenic differentiation. Expression of PGE2 receptors (EP1‐EP4) was determined by real‐time PCR. EP1 and EP4 were highly expressed, whereas EP2 and EP3 were not detectable. Specific inhibitors SC 51322 for EP1 or L161,982 for EP4 significantly attenuated myogenesis. EP1 inhibition reduced the number of early myotubes, and subsequently affected the development of mature myotubes. On the other hand, EP4 inhibition did not affect the generation of early myotubes, but the fusion of early myotubes was dramatically inhibited. Interestingly, expression of two key myogenic regulatory factors, MyoD and Myogenin, was downregulated by EP1, but not by EP4 inhibition. These data provide evidence for the regulation of myogenesis by PGE2 via EP1 and EP4. The different effects of EP1 and EP4 inhibition suggest PGE2 signaling in myogenic differentiation is complex and multiple‐faceted. Support: NIH RC2 AR058962, Missouri Life Sciences Research Board(MB), and NIDCR DE021888(OJI).
Satellite Cells are not Prerequisite for Skeletal Muscle Regrowth Following Unloading‐Induced Atrophy
Authors: Jackson Janna Renee , Fry Chris S. , Lee Jonah D. , Mula Jyothi , Erfani Rod A. , Kirby Tyler J. , Ubele Margo F. , Lawson Ben A. , Campbell Ken S. , McCarthy John J. , Peterson Charlotte A. , Dupont-Versteegden Esther E.
Published: June 2021

Resident muscle stem cells, known as satellite cells, are thought to be hallmarks of skeletal muscle plasticity. It is generally well accepted that satellite cells are essential for muscle regeneration following injury, however, their role in muscle regrowth following an atrophic stimuli remains unclear. The current study employed a genetically modified mouse model (Pax7‐DTA) that allowed for the effective ablation of >90% of satellite cells in adulthood. Control and satellite cell ablated young female mice were either hindlimb suspended (HS) for 14 days, or HS for 14 days followed by 14 days of reloading to follow regrowth. Muscle atrophy as measured by whole muscle wet weight, fiber cross‐sectional area and single‐fiber width occurred in response to HS and did not differ between satellite cell ablated muscles and control muscles. Furthermore, the absence of satellite cells did not attenuate muscle mass recovery during the reloading period, suggesting that satellite cells are not mandatory for muscle regrowth. Interestingly, the myonuclei from satellite cell ablated muscles were longer than myonuclei from non‐ablated muscles, alluding to a potential mechanism of regulation between satellite cells and myonuclear size. The data from the present study suggest that satellite cells are not a requirement for muscle regrowth following atrophy; however, their absence may alter myonuclear size. NIAMS: R01AR060701
Low Intensity Exercise Attenuates Acute Lipid Loading‐Induced Alterations in Mitochondrial Function in Rat Skeletal Muscle
Authors: Lin Chien-Te , Fisher-Wellman Kelsey H. , Perry Christopher G.R. , Kozy Rachel , Lark Daniel S. , Gilliam Laura A. A. , Smith Cody D. , Neufer Darrell P.
Published: June 2021

A single high‐fat meal acutely increases skeletal muscle mitochondrial H2O2 emitting potential (mEH2O2), shifts the intracellular redox environment to a more oxidized state, and increases circulating markers of oxidative stress. Bioenergetically, this implies an acute lipid load may elevate the reducing pressure/membrane potential (Δ Ψm) within mitochondria and, conversely, that even a mild increase in energy expenditure may be sufficient to prevent these effects. To test this hypothesis, male Sprague‐Dawley rats received an oral lipid gavage (20% intralipid, 45 Kcal/kg lean body mass) or water followed either by 2h of rest or 1h of rest plus 1h of low intensity treadmill exercise (15 m/min, 0% grade). Permeabilized fiber bundles were prepared from red gastrocnemius muscle for testing mitochondrial function. In rats receiving lipid, Δ Ψm and mEH2O2 were higher (P<0.05) and calcium retention capacity (mCa2+ RC, an index of resistance to mitochondrial permeability transition) was lower under state IV and/or “clamped” ADP‐stimulated state III conditions. All three effects were prevented when lipid gavage was followed by low‐intensity exercise. Respiratory capacity was unaffected by any of the interventions. These findings provide evidence that mitochondrial Δ Ψm, mEH2O2, and mCa2+ RC are acutely affected by nutritional overload in skeletal muscle, but can be prevented by low intensity exercise. NIH DK073488
Effect of Bepridil in postfatigue tension of slow fibers of skeletal muscle
Authors: Vázquez-Rivera Dolores , Montoya-Pérez Rocío , Trujillo Xóchitl , Huerta Miguel , Sánchez-Duarte Elizabeth , Cortés-Rojo Christian , Meza-Carmen Victor , Saavedra-Molina Alfredo
Published: June 2021

Fatigue is conceived as a reduction in physical strength or a reduction in the maintenance of energy production (Allen et al. 2008). KATP channels were described in 1983 by Noma; these channels monitored the intracellular levels of ATP and regulate the excitability of the membrane (Kristensen et al. 2006, Tricarico. 2010). Mitochondrial KATP channels were identified in the mitochondrial inner membrane by Inoue et al. 1991, they play a central role in ischemic pre‐conditioning process, and therefore it is in our interest to study the effect of Bepridil, during post‐fatigue, due to induces mitochondrial swelling and consequently the maintenance of energy production during a period demand of it.

Anterior Latissimus Dorsi (ALD) muscles were obtained of chickens, between 1 and 3 weeks old. The muscle was mounted on an experimental recording chamber by placing the proximal end to the bottom of the chamber and the distal end to the hook mechanoelectric transducer (Grass FT03), which through an amplifier and a 320 CyberAmp analog‐digital interface (Digidata 1322A) allowed to acquire by a computer (Pentium 4) the muscle tension generated, date was process with the sofware AXOTAPE (pCLAMP 9.2). Electrical stimulation induced fatigue (pulses of 100 V, 300 ms duration, frequency of 0.2 Hz). The bundle was stimulated until the force decreased by 70 %, then applied Bepridil (1, 10 and 100 μM) for 6 min to observe its effect. We obtained a dose‐response curves of Bepridil, with greater effect at 10 μM over 300 % (p= 0.04 for peak tension and p=0.008 for total tension).
Glucocorticoids attenuate calcineurin signaling and PGC‐1α expression in muscle during diabetes and kidney disease
Authors: Price Russ , Zheng Bin , Gooch Jennifer
Published: June 2021

Reduced expression of PGC‐1α has been linked to skeletal muscle atrophy in chronic diseases. We previously found that diabetes (DM) and chronic kidney disease (CKD) decrease calcineurin (Cn) phosphatase activity; signaling through its downstream effectors MEF2 and NFATc; and PGC‐1α. Since glucocorticoids are elevated in both conditions and required for muscle atrophy, we investigated if they mediate the changes in Cn signaling and PGC‐1α expression seen in CKD and DM. L6 myotubes were treated with dexamethasone (DEX; 100 nM) to evaluate changes in Cn signaling. Levels of the Cn A catalytic subunit (CnA), NFATc3, and MEF2 were evaluated by Western blot analysis of cytosolic and nuclear cell fractions. NFATc3 and MEF2 proteins were significantly reduced (P<0.05) in the nuclear fraction of cells treated with DEX for 1 hour. CnA is a known substrate of the atrophy‐related MAFbx/atrogin‐1 E3 ubiquitin ligase protein. It was unchanged in both the cytosol and nucleus after ≤ 1 h of DEX but Cn activity in cells was reduced by 28%. In contrast, nuclear CnA was decreased ~50% after 48 h of DEX. Chronic DEX treatment also suppressed the levels of MRF4 and MCIP1.4 mRNA, respective gene targets of MEF2 and NFATc, as well as PGC‐1α expression, as evaluated using a PGC‐1α‐luciferase reporter gene. Our results indicate that glucocorticoids mediate the changes in Cn signaling and PGC‐1α during chronic diseases.
A stochastic and integrative model of breathing with temporal scaling characteristics
Authors: BuSha Brett Francis , Frone Shannon
Published: June 2021

Even during quiet wakefulness, there is a natural fluctuation of the output of the respiratory control system, which results in a distribution of breath to breath characteristics over time. The objective of this study was to design a stochastic and integrative model of breathing (SIMB) that utilized a probability density function (PDF) to reproduce the natural distribution pattern and temporal scaling of human breathing. A least sum of squares approach was used to optimize the fit of several PDF functions (extreme value, gamma, generalized extreme value, lognormal, and Weibull) to a sequential recording of 2048 breath to breath intervals (BBI). The three distributions with the lowest fitting errors were selected; Weibull, generalized extreme value, and gamma. Each distribution was used to generate input data for the SIMB, and 10 artificial BBI sequences were produced with each distribution. Detrended fluctuation analysis (DFA) was used to quantify fractal scaling of the output of the SIMB for each distribution. The morphology of the BBI distributions of the SIMB was similar to the original distributions that were generated with the optimized PDFs, and all SIMB generated breathing sequences contained significant fractal scaling (P < 0.01). In conclusion, a new stochastic model of breathing was designed, and optimized to reproduce the distribution and fractal properties found in normal adult breathing.
A novel transcription mechanism activated by ethanol: induction of Slc7a11 expression via inhibiting the DNA‐binding activity of repressor OCT1 in mouse hepatic stellate cells
Authors: Lin Xinghua , Yang Hong , Zhang Hongfeng , Zhou LiChun , Guo ZhongMao
Published: June 2021

The objective of this study is to determine the mechanism underlying ethanol‐induced expression of solute carrier family 7 member 11 (Slc7a11). Quantitative real‐time RT‐PCR assay, western blot analysis, promoter activity assays and chromatin immunoprecipitation analysis were performed in this study. Our data demonstrated that ethanol significantly increased Slc7a11 mRNA and protein expression in mouse hepatic stellate cells. Deletion of 20‐bp DNA sequence between −2044 to −2024 upstream of the transcription start site significantly increased the basal activity, and completely abolished the ethanol‐induced activity of the Slc7a11 promoter. DNA sequence analysis reveals a biding motif for octamer‐binding transcription factor 1 (OCT‐1) in this deleted fragment. Similarly, mutation of this OCT‐1 binding motif significantly increased the basal promoter activity and abolished the response to ethanol. In addition, Ethanol exposure significantly inhibited OCT‐1 binding to the Slc7a11 promoter region, while the OCT‐1 mRNA and protein levels were comparable in cells treated with or without ethanol. Results from the present study suggest that OCT‐1 functions as a repressor on the Slc7a11 promoter, and that ethanol inhibits OCT‐1 binding to the Slc7a11 promoter, and therefore increases Slc7a11 expression. Grant support: R01HL089382 (ZhongMao Guo) and SC1HL101431 (Hong Yang).
Induction of Klf15 by glucocorticoids in the lung regulates downstream transcriptional effects on mitochondrial function and metabolism
Authors: Gerber Anthony Nicholas , Sasse Sarah , Haldar Saptarsi , Jain Mukesh
Published: June 2021

The objective of this study was to determine whether direct induction of Klf15 expression by the glucocorticoid receptor (GR) in the lung regulates downstream effects of glucocorticoids on pulmonary gene expression. We used chromatin immunoprecipitation and reporter assays to identify two functional GR binding sites in the Klf15 locus through which the GR directly induces Klf15 expression in airway epithelial cells. Microarray‐based expression profiling comparing wild type and Klf15−/− mice showed that ~ 5% of gene expression changes in the lung after 8 hours of dexamethasone treatment depend on Klf15 activity. Gene ontology analysis indicated that the set of GR:Klf15 target genes is enriched for genes involved in metabolism and mitochondrial function. We conclude that direct induction of Klf15 in the lung by GR regulates the expression of a gene subset implicated in pulmonary metabolism and mitochondrial function. We speculate that local modulation of metabolic activity in the lung through the GR:Klf15 axis plays a crucial role in modulating energy mobilization and utilization in the lung during stressors such as infection or starvation. Supported by NIH/NHLBI P30HL101294.
Coordinate adenosine A1 and A2A receptors regulation of the Na+/H+ exchanger 3 in ischemia/reperfusion injury
Authors: Babich Victor , Vadnagara Komal , Moe Orson W , Di Sole Francesca
Published: June 2021

Acute kidney injury, due to ischemia/reperfusion injury (IRI), is associated with high morbidity and mortality and lacks specific therapeutic measures. Na+ absorption is severely compromised by IRI and both surface and total protein of the principal proximal tubule Na+ transporter, the Na+/H+ exchanger 3 (NHE3), are markedly decreased following IRI. We found that coordinate pharmacological activation of adenosine receptor subtype 1 (A1R) and 2A (A2AR) protected against IRI. Compared to vehicle‐treated ischemic rats, A1R agonist, given before ischemia, and A2AR agonist, given after ischemia, decreased the peak of plasma creatinine (Cr) and blood urea nitrogen (BUN) 24 hours after IRI and accelerated their reversal thereafter. We next examined how A1R and A2AR affect NHE3 protein expression in IRI. A1R agonist, given before ischemia, did not affect the drop in NHE3 surface, but blunted IRI‐induced reduction in NHE3 total protein. A2AR agonist, given after ischemia, reversed the decrease in NHE3 surface but did not affect loss of NHE3 total protein mediated by IRI. In summary, activation of A1R and A2AR synergistically reduced the peak and accelerated the reversal of Cr and BUN following IRI. A1R and A2AR act differently, but in conjunction, to preserve NHE3 protein and move it back to cell surface after IRI. Modulation of NHE3 protein expression may be a key mechanism by which A1R and A2AR mediate protection against IRI.
Alternatively spliced PY cassette exons in WNK1 enhance sensitivity to aldosterone via the E3 ubiquitin ligase Nedd4‐2
Authors: Roy Ankita , Khadem Shaheen , Donnelly Bridget F. , Gong Fan , Pastor-Soler Nuria M. , Chang Y.P. Christy , Subramanya Arohan R.
Published: June 2021

Aldosterone stimulates NaCl reabsorption in the distal nephron in part by increasing thiazide‐sensitive cotransporter (NCC) phosphorylation. Through undefined upstream mechanisms, WNK1 kinase participates in this process by activating SPAK and OSR1, which phosphorylate NCC directly. In the kidney, WNK1 is expressed as kinase active (L‐WNK1) and defective (KS‐WNK1) isoforms; exons 11 and 12 are differentially spliced into both gene products, but the role of these events in WNK1 function is unclear. Here, we explore how exons 11 and 12 link WNK1 to aldosterone action. Both exons harbor PY motifs ([L/P]PXY); these conserved sequences are absent from the rest of WNK1 and are binding sites for Nedd4‐2, an E3 ligase which is inhibited by the aldo‐induced kinase SGK1. In mammalian cells, Nedd 4‐2 associated with WNK1, accelerating its degradation by the ubiquitin proteasome pathway in a PY motif dependent manner. In mpkCCD cells, 100nM aldosterone increased L‐WNK and KS‐WNK1 protein abundance within 2h, and both isoforms formed an endogenous complex with Nedd 4‐2 and SGK1. Antisera specific to exon 12 confirmed the enrichment of Nedd4‐2 sensitive WNK1 isoforms in the distal nephron. These results suggest that exons 11 and 12 function as modular “PY cassettes” that alter WNK1 abundance in response to aldosterone via Nedd4‐2, revealing a mechanism that directly connects aldosterone signaling to NCC phosphorylation.
Sexual dimorphism and estrogen regulation of KCNE3 modulates the functional properties of KCNQ1 K+ channels
Authors: Harvey Brian Joseph , Alazamora Rodrigo , O'Mahony Fiona , Bustos Viviana , Rapetti-Mauss Raphael , Urbach Valerie , Cid Pablo , Sepúlveda Francisco
Published: June 2021

Estrogen exerts a female‐specific anti‐secretory response in epithelia via KCNQ1:KCNE3 channel inhibition (O'Mahony et al., 2009. J Physiol. 587:5039–44). The purpose of this study was to determine the molecular mechanisms by which sex and estrogen regulate the expression and function of KCNQ1 and KCNE3 in rat distal colon. KCNE1 and KCNE3 mRNA and protein abundance were significantly higher in male than female colonic crypts. KCNQ1 and KCNE3 protein expression fluctuated throughout the estrous cycle and 17β‐estradiol (E2 10 nM) produced a rapid (<15 min) dissociation of KCNQ1 and KCNE3 in female crypts only. The effect of E2 on K+ currents mediated by KCNQ1 with or without different β‐subunits was assayed from current‐voltage relations elicited in CHO cells transfected with KCNQ1 and KCNE3 or KCNE1 cDNA. E2 reduced the currents mediated by the KCNQ1:KCNE3 potassium channel and had no effect on currents via KCNQ1:KCNE1 or KCNQ1 alone. Mutation of a serine to an alanine, S82A, on the cytosolic side of KCNE3, prevented E2 induced PKCδ phosphorylation of KCNE3 and caused insensitivity of KCNQ1 currents to E2. KCNE3 phosphorylation and decreased association of the KCNQ1:KCNE3 channel complex promoted by estrogen underlie the molecular mechanisms for the sexual dimorphism and estrous cycle dependence of the anti‐secretory actions of estrogen in the intestine.
Inflammation Causes Important Changes in Stomach Tight Junction Structure and Function
Authors: Hagen Susan J , Zhang Songhua , Seo Ji Hye , Fox James G.
Published: June 2021

Little is known about the role of inflammation in tight junction regulation during Helicobacter pylori (HP) infection. We thus examined the role of cytokines in gastric barrier function.

Methods

Cultured gastric chief cells were incubated with IFN‐γ, TNF‐α, and IL1‐β individually or as a cytomix. Transepithelial resistance (TER) and paracellular permeability were determined without or with specific inhibitors to block IL1‐β receptor‐mediated signaling pathways. Western blots and immunostaining were done using specific antibodies. B6/129 mice infected with HP were used to verify the culture results in a mouse cancer model.

Results

Cytomix significantly reduced TER and increased paracellular permeability by IL1‐β signaling through p38 MAPK but not other IL1‐induced pathways. Cytomix exposure affected the expression of two important tight junction claudins; claudin18 was completely attenuated and claudin7 was highly up‐regulated. This claudin18/claudin7 “switch” also occurred in tissues from HP‐infected mice.

Conclusions

Inflammation‐induced IL1 signaling through p38 MAPK causes barrier defects in cultured gastric cells. In particular, claudin18, which is barrier‐forming, is attenuated by IL1 signaling. These data suggest that during inflammation, IL1 regulates the composition and function of tight junctions in stomach. This work was supported by NIH DK015681 and by Departmental funding.
Caveolin‐1 Phosphorylation by Src Kinase Regulates Epithelial Restitution by Altering Store‐Operated Ca2+ Influx
Authors: Rao Jaladanki N , Rathor Navneeta , Zhuang Ran , Zou Tongtong , Liu Lan , Xiao Lan , Wang Jian-Ying
Published: June 2021

Early mucosal restitution occurs as a consequence of intestinal epithelial cell (IEC) migration to reseal superficial wounds. Our previous study shows that caveolin‐1 (Cav1) enhances store‐operated Ca2+ entry (SOCE) and is implicated in the control of intestinal epithelial restitution, but the exact mechanism by which Cav1 activity is regulated remains elusive. This study determine if c‐Src kinase modulates Cav1, thus activating Cav1‐mediated SOCE after wounding. [Ca2+]cyt, Cav1/c‐Src interaction, and restitution were measured in differentiated IEC cells. c‐Src directly interacted with and phosphorylated Cav1 in IECs. Inhibition of c‐Src activity by PP2 prevented c‐Src/Cav1 interaction, reduced Cav1 phosphorylation, decreased Ca2+ influx after store depletion, and inhibited cell migration after wounding. Disruption of caveolar lipid raft microdomains by methyl‐β‐cyclodextrin (MβCD) or by blocking a functional caveolin‐scaffolding domain with CSD decreased Cav1/c‐Src association, reduced Cav1 phosphorylation and SOCE, and repressed epithelial restitution. The levels of SOCE were inhibited by ~65% and ~80% after treatment with MβCD and CSD peptides, respectively, and cell migration was decreased by ~40%. These results indicate that 1) c‐Src phosphorylates Cav1 and activates its activity 2) c‐ Src‐mediated Cav1 stimulates epithelial restitution by increasing Ca2+ signaling. Grants: NIH/VA
The absence of LPA1 results in aberrant intestinal epithelial cell migration
Authors: Lee Sei-Jung , Nusrat Asma , Chun Jerold , Yun C. Chris
Published: June 2021

Lysophosphatidic acid (LPA) is a potent inducer of epithelial cell migration. The LPA receptor subptype, LPA1, is the most abundant LPA receptor in the intestinal tract; however its physiological significance remains elusive. We found that the villous height is shortened in the intestine of LPA1‐null mice (Lpar1−/−) compared with wild type (WT) mice and the rate of migration of proliferating enterocytes along the crypt‐villus axis is impaired in Lpar1−/− mice. Injection of WT mice with LPA1/LPA3 inhibitor Ki16425 decreased cell migration towards the villus tip, whereas oral administration of LPA enhanced cell migration. LPA failed to promote cell migration in Lpar1−/− mice, suggesting that LPA1 specifically regulates enterocyte migration in the mouse intestine. We further studied the mechanism of LPA1‐mediated migration in YAMC cells. Overexpression of LPA1 markedly enhanced lamellipodia formation and cell migration, whereas LPA2 had a marginal effect. The downstream signaling pathway initiated by LPA1 for YAMC cell migration involves Gαq specifically activating PLC‐β2, but not other PLC‐β isoforms. PLC‐β2 interacted with GTP‐bound Rac1 to recruit Src and Arp2/3 to the leading edge of lamellipodia, where Src and Arp2/3 interacted with FAK and cortactin, respectively. These results suggest that LPA1 is the major LPA receptor that regulates migration of proliferating enterocytes in the intestinal tract.
The ErbB4 receptor tyrosine kinase protects colonocytes from apoptosis in vitro and in vivo
Authors: Frey Mark R , Bernard Jessica K
Published: June 2021

The ErbB4 tyrosine kinase is highly expressed in colitis. In cell culture, its overexpression blocks tumor necrosis factor (TNF)‐induced colonocyte apoptosis, suggesting that induction in disease may be protective. In this study, we used the ErbB4‐specific ligand neuregulin‐4 (NRG4) to activate the receptor and define its role in cell survival.

METHODS

Mouse colon epithelial cells expressing ErbB4 (MCE‐ErbB4) were exposed to TNF +/− NRG4. 6–8 week‐old C57Bl/6 mice were given TNF +/− NRG4 by i.p. injection. Cell counts in vitro were determined by MTS assay; signaling and apoptosis were assessed by western blot of cell lysates and mucosal scrapings or immunohistochemical analysis of formalin‐fixed tissue. Src and phosphatidylinositol 3‐kinase (PI3K) were inhibited with PP2 and LY294002, respectively.

RESULTS

NRG4 blocked TNF‐induced caspase‐3 cleavage and cell death in vitro (cell loss reduced by 64.8%; p<0.03), and inhibited TNF‐induced apoptosis (assessed by caspase‐3 cleavage) in vivo by 71% (p<0.05). NRG4‐treated MCE‐ErbB4 cells and colonic mucosal scrapings from NRG4‐injected mice showed elevated Akt and Src activation. In vitro inhibition of Src or PI3K reversed NRG4's protective effects on MCE‐ErbB4 cells.

CONCLUSIONS

ErbB4 activation by NRG4 promotes colonocyte survival both in vitro and in vivo, likely through a Src‐ and PI3K‐dependent pathway. Exogenous NRG4 may be therapeutic for colitis.
Cancer Stem Cells in the Age‐related Progression of Colorectal Cancer: Role of EGFR
Authors: Majumdar Adhip P.N. , Leavell Bonita , Du Jianhua , Yang Liu , Antaki Fadi
Published: June 2021

One of the most consistent pathological conditions in the gastrointestinal (GI) tract with advancing age is malignancy, particularly colorectal cancer, the incidence of which increases sharply with advancing age. The regulatory mechanisms are poorly understood. Recent evidence suggests that colorectal cancer is driven by self‐renewing cancer stem cells (CSCs). Earlier, we reported that the age‐related increase in adenomas was associated with increased expression of CSC markers in the macroscopically normal mucosa suggesting a role for CSCs in the development of colorectal neoplasia. Indeed, FACS analysis of cells isolated from colonic biopsies of patients with adenomas over 60 years of age revealed a higher proportion of colonocytes expressing CD44+166− and CD44+CD166+ phenotypes than their younger counterparts. This was accompanied by a concomitant increase in EGFR in the colonic mucosa, indicating a relationship between CSCs and EGFR. Moreover, we found EGFR to be coexpressed with CD166 in the colonic crypts and that their co‐expression was significantly higher in older patients. This co‐expression was even more evident in adenomas and highest in carcinomas. In conclusion, our data suggest that EGFR plays a pivotal role in the age‐related increase in CSCs which may promote their carcinogenic potential.
Effects of whole walnuts and walnut components on postprandial triglyceride response, plasma measures of antioxidant activity, and endothelial function in overweight and obese adults
Authors: Berryman Claire E , West Sheila G , Grieger Jessica A , Blumberg Jeffrey B , Kris-Etherton Penny M
Published: June 2021

Walnuts beneficially affect endothelial function and oxidative stress. Mechanisms specific to walnut components are not known. We evaluated acute, postprandial effects of walnut components [separated nut skins (5.6 g), de‐fatted nutmeat (34 g), and nut oil (51 g)] versus whole walnuts (85 g) on metabolic parameters. Overweight/obese adults (9 women/6 men) with moderate hypercholesterolemia were randomized to a 4‐period crossover study design. There was a treatment by time interaction (P < 0.01) for TG. Post hoc tests showed that oil increased TG versus nutmeat and skins at 120 min and 240 min versus skins; the whole nut increased TG versus skins at 120 min and 240 min (P < 0.01 for all). Ferric reducing antioxidant power was different between nutmeat and oil and nutmeat and skins (P < 0.01 for both). Skins decreased the reactive hyperemia index (RHI) versus baseline (P < 0.01), and oil improved RHI versus skins (P < 0.01). For the Framingham RHI (fRHI), oil was greater than skins and the whole nut (P < 0.01 for both). For the oil treatment, ex vivo cholesterol efflux correlated with RHI and fRHI (r = 0.35, P = 0.07; r = 0.39, P = 0.04). There were no differences in total thiols or malondialdehyde. Walnut oil improved endothelial function compared to the skins, and these changes were associated with improved reverse cholesterol transport. Measurement timing, extraction method, and/or bioavailability may help explain these effects.

Grant Funding Source: California Walnut Commission and the GCRC, PSU (NIH grant M01RR10732); ClincalTrials.gov identifier: NCT00938340
Whole‐grain intake and risk of all‐cause mortality among elderly men and women: the Cache, County Study on Memory, Health and Aging
Authors: Wengreen Heidi , Quach Anna , Cutler Adele , Munger Ronald , Corcoran Christopher
Published: June 2021

Objective

This study examines associations between whole‐grain consumption and all‐cause mortality among elderly men and women of the Cache County Study on Memory, Health and Aging.

Design

Participants were 3624 men and women 65 years of age or older who were living in Cache County, Utah in 1995. Participants completed a food frequency questionnaire and survey of health‐related behaviors. Proportional hazards survival analyses were used to assess the associations between increasing quintile (Q) of whole‐grain intake and risk of death by any cause. Covariates included age, gender, body mass index, level of physical activity, history of smoking and vascular disease, and incidence of dementia.

Results

Over a 12‐year‐follow‐up period, increasing whole‐grain intake was inversely associated with total mortality. The relative hazards of death for Q2‐5 of whole grain intake compared to Q1 were 0.80 (95% CI: 0.68, 0.94), 0.80 (0.69, 0.94), 0.77 (0.66, 0.90), and 0.72 (0.62, 0.85), respectively (P = 0.0009).

Conclusion

In this population study of elderly men and women, consuming in the highest quintile of whole‐grain intake was associated with almost a 30% lower risk of death compared to the lowest quintile. The findings suggest a potential health benefit of whole‐grain intake among elderly men and women.
Frequency of candy consumption and dietary and health characteristics of adults age 19–50 y in the United States
Authors: Murphy Mary M , Barraj Leila M , Bi Xiaoyu , Shumow Laura , Bodor Alison R
Published: June 2021

The purpose of this study was to estimate usual nutrient intakes and body weight, blood pressure, and cholesterol status of male and female adults age 19–50 y by usual frequency of candy eating occasions (EO). Using data reported in NHANES 2003–06, adults were categorized as infrequent (≤ 3 EO/mo), moderate (> 3 EO/mo and ≤ 3.5 EO/wk), or frequent (> 3.5 EO/wk) candy consumers based on the combined frequency of chocolate and other candy intake over the previous 12 mo. Usual energy intake increased with increased frequency of candy intake (p<0.01) among both males (2768 ± 42.2, 2894 ± 33.0, 2995 ± 44.1 kcal) and females (1841 ± 23.5, 1883 ± 23.3, 2041 ± 31.0 kcal), as did usual intake of fat, total sugars and added sugars. There were no significant differences in prevalence of overweight/obesity (BMI ≥ 25.0) or mean waist circumference by frequency of candy intake. Blood pressure and total, HDL, and LDL cholesterol status did not differ across frequency of candy consumption groups. Findings from this study indicate that despite higher energy intakes by adults with increased usual frequency of candy intake, higher frequency of candy intake was not associated with adverse effects on BMI status, waist circumference, blood pressure status, or cholesterol status. Further research is warranted to identify dietary and lifestyle patterns of adults by frequency of candy consumption. Supported by the National Confectioners Association.
Serum and red blood cell folate status of New Zealanders: results from a national nutrition survey
Authors: Bradbury Kathryn , Skeaff Clark , Williams Sheila , Mann Jim , Brown Rachel , Parnell Winsome
Published: June 2021

Folic acid consumed peri‐conceptionally reduces the risk of neural tube defect‐affected pregnancies. The objective of this research was to assess the folate status of a nationally representative sample of New Zealand adults, 15 y or older, prior to the introduction of mandatory folic acid fortification of bread scheduled for 2012.

Serum and red blood cell folate concentrations were measured microbiologically in non‐fasting blood samples collected from 3348 participants in the 2008/09 New Zealand Adult Nutrition Survey.

In total, 1.6% (95%CI: 1.1, 2.2) of participants had serum folate concentrations less than 6.8 nmol/L, and 2.2% (1.4, 2.9) of participants had red blood cell folate concentrations less than 317 nmol/L indicative of deficiency. Mean (95%CI) red blood cell folate concentration amongst women aged 16 to 44 y was 796 nmol/L (758, 834); 27.4% (23.0, 31.7) had red blood cell folate concentrations ≥ 906 nmol/L.

The prevalence of biochemical folate deficiency was low. However, more than two thirds of women of child‐bearing age had folate status associated with higher risk of neural tube defect‐affected pregnancies. Mandatory fortification of bread with folic acid is likely to reduce the incidence of neural tube defects in New Zealand.

Source of Funding: The Ministry of Health, New Zealand, funded the 2008/09 New Zealand Adult Nutrition Survey.
Age and nutritional status influence peripheral immune cell phenotypes in healthy men in rural Pakistan
Authors: Alam Iftikhar , Pawelec Graham
Published: June 2021

Immune status is influenced by age and malnutrition. How these factors interact in developing countries and whether age‐associated differences are similar to those determined in industrialized countries is unclear, and were therefore, investigated in this study.

Peripheral blood immune cell phenotypes were analyzed by polychromatic flow cytometry in young and elderly subjects. Data on anthropometrics and diet were collected through interviews. Plasma samples were analyzed for common clinical chemistry variables.

As a group, elderly had a significantly lower CD4:CD8 ratio, a lower percentage of CD8+ naïve T cells and significantly higher late‐differentiated memory cells. These results were broadly similar to those in industrialized countries. Subjects in 4 BMI categories revealed an influence of nutritional status on immune parameters. This was greater within the young group, and unlike age, affected the CD4 subset more profoundly than the CD8 subset. No age‐ or nutrition‐associated differences were seen in B or NK cells. CD8+ cells as a percentage of CD3+ T cells were positively associated with plasma CRP levels but not other factors.

We conclude that immune profiles in younger and older men in a developing country seem broadly similar to the more extensively‐documented state reported in industrialized countries, despite the marked societal, nutritional and many other differences.

The study was funded by the German Academic Exchange Program (DAAD), and EU FP7 contract 259679 “IDEAL”…….

Grant Funding Source: ASN
Comparison food and nutrient intake estimates modeled using 14‐day diaries to estimates derived from two 24‐hour recalls
Authors: Barraj Leila M , Srinivasan Jannavi , Brookmire Lauren , Bi Xiaoyu , DiNovi Michael
Published: June 2021

The US FDA relies on data from the National Health and Nutrition Examination Survey (NHANES) to estimate food and nutrient intake for the US population. NHANES collect consumption data via two 24‐hour dietary recalls. Short‐term recall data from NHANES do not accurately represent chronic intake of food, and surveys of longer duration are needed to more accurately estimate long‐term intake. We developed a model that combines data from NHANES 24‐hr recall and 14‐day consumption diaries collected from a nationally representative sample of the US population by The NPD Group as part of the National Eating Trends survey. We compared intake estimates derived using our model to 2‐day average estimates based on the dietary recall data. Percent consumers, mean and 90th percentile intake estimates were generally comparable for relatively frequently consumed foods, e.g., milk intake (2‐day: 93%, 285 & 630 g/d; 14‐day: 91%, 280 & 585 g/d). For less frequently consumed foods, larger differences were observed, e.g., egg intake (2‐day: 34%, 67 & 126 g/d; 14‐day: 69%, 18 & 38 g/d). The long‐term estimates were also generally comparable to estimates derived using statistical methods (e.g., NCI method). These results confirm that data from short‐term dietary surveys underestimate the number of consumers and over estimate intakes at the upper percentiles for actual consumers. Supported by the US Food and Drug Administration.
Teaching discipline‐independent skills in anatomy
Authors: Pawlina Wojciech
Published: June 2021

Dramatic changes in the anatomical sciences education challenged the anatomy faculty and their education philosophy. As medical curriculum evolves, conventional courses need to adopt a new system of instruction. The overarching objective of an anatomy course is to provide anatomy‐specific knowledge and concepts for clinical application. However in the new environment, anatomy courses must incorporate other longitudinal objectives that will be revisited in clinical courses. These include discipline‐independent subjects such as leadership, teamwork, professionalism, and effective communication. Leadership can be fostered through classroom team‐based learning activities under the direction of a designated student team leader. Students are actively immersed in collaborative learning and as a team are responsible for obtaining, sharing, and presenting knowledge to other classmates. Professionalism in the classroom entails acts of dutifulness and respect for others. Emphasis on peer‐teaching results in development of communication skills that ensure effective transfer of knowledge and information between the members of the learning team. Also, an early introduction of peer and self evaluations result in enhancing assessment skills. The design of the contemporary anatomy curriculum must implement student‐centered approaches.
No ‘I’ in Anatomy: Group Cadaveric Dissection
Authors: Kour Louis , Cassidy Ethan , Roth Jeremy , Wilson Timothy D
Published: June 2021

With the advent of new teaching technologies, gross anatomical education has come under heavy scrutiny. Much of the research focuses on quantitative outcomes; content‐related post‐tests are often the metric for comparison. However, there is a paucity of research surrounding the social nature of interpersonal interaction pertaining to learning around a cadaver. Using a case‐study approach, we will begin to explore the social nature of the cadaver laboratory. The roles filled by students around the dissection table are of special interest. Four random second‐year undergraduate Kinesiology lab groups (n=20) were observed over a nine‐week period during routine labs. Observations were made using recorded video and observational field notes. Participants were also invited to an interview to explore pertinent observations further. Through systematic analysis, we will identify and describe roles within the social context of the laboratory. It is hoped that a better understanding of the qualitative aspects of the laboratory might better inform curricular architecture in the future.

Grant Funding Source: Queen Elizabeth Scholarship and Western Graduate Research Scholarship
Early wasting in India: a public health challenge
Authors: Young Melissa Fox , Martorell Reynaldo
Published: June 2021

A new pattern of wasting by age emerged with the use of the WHO growth curves in India. The highest rates of wasting (30%) are in the first six months and decrease thereafter. This represents a public health challenge as both the determinants and solutions are unclear. Traditional food‐based supplements are not appropriate for this population. Data from the 2005–2006 National Family Health Survey 3 was used to examine the determinants of early wasting in India with a focus on potentially modifiable factors (poor condition of mothers/breastfeeding practices). The results (odds ratios; 95%CI) of an unadjusted model predicting wasting in infants < 6 mo were the following: maternal variables [BMI < 18.5 k/m2 (1.31;1.07–1.61), height < 150 cm (1.11;0.92–1.35), age ≤18 years at first birth (0.94; 0.76–1.16), anemic (1.24;1.00–1.53)], breastfeeding within 1 hr of birth (0.71;0.55–0.93), receiving prelacteal feed (1.07;0.86–1.32), and exclusive breastfeeding (0.90;0.73–1.11). After adjusting for covariates (child age/sex/birth‐order, residence, maternal education/occupation, marital status, wealth, caste and religion), having a thin mother (1.31; 1.05–1.63) and early breastfeeding (0.68; 0.52–0.90) remained significant predictors. Priority areas for preventing the onset of early wasting should include improving the mother's nutrition before and during pregnancy and promotion of breastfeeding.

Grant Funding Source : Funding support provided by a BMGF grant through a subcontract with CARE‐India
Long‐term Dietary patterns in China, 1991–2009
Authors: Batis Carolina , Zhang Bing , Popkin Barry
Published: June 2021

Little is known about dietary patterns over time in transitional societies. Using the China Health and Nutrition Survey, we followed 3012 adults aged 18 y or older in 1991 with complete dietary data in each of 7 waves (1991, 1993, 1997, 2000, 2004, 2006 and 2009). Diet was measured by a combination of a household food inventory (detailed weighing of changes in household food) and 3 consecutive days of 24‐h recall. Dietary intake was grouped into 42 food groups. A factor analysis (STATA 12), followed by a varimax orthogonal rotation was performed at each wave. Factors with eigenvalues >1 were retained.

Two clear patterns emerge over time. One was linked with a diet high in rice, vegetables, high‐fat red meat and fish, and inversely associated with wheat and corn intake. This pattern remained relatively similar in all waves. A second pattern was associated with high animal products intake (red and organ meats, poultry, eggs, fish and sea products) in all waves. During the series of surveys, other food groups began to be linked with this same dietary pattern: alcohol (beginning in 1993), pastries, cookies, deep‐fried cereals and fruits (beginning in 1997), fast‐food (in 2006), and sweetened dairy (in 2009).

These results provide insights into the dynamic shifts in a major unhealthy eating pattern in China as the economy shifted and new products were introduced into the food distribution system.

Grant Funding Source : CONACYT (grant 212018), NIH (R01‐HD30880), the Fogarty International Center (D43‐TW009077)