bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recruitment of Eosinophils to Lungs and Their Role in Vagally Mediated Airway Hyperreactivity Depends upon TNFa and Sensitization Status
Authors: Wicher Sarah A. , Jacoby David B. , Fryer Allison D. 
Published: November 2023

BackgroundFifty‐percent of Americans are routinely exposed to high levels of ozone. Inhaled ozone transiently reduces lung function in healthy individuals, and induces severe exacerbations of airway disease in asthmatics. Since many asthmatics have airway eosinophilia, we evaluated the interaction of ozone and eosinophils in lungs of guinea pigs. We found that eosinophils mediate ozone‐induced airway hyperreactivity 1 day after exposure, but were paradoxically protective against airway hyperreactivity at 3 days. This protective function of eosinophils was lost in guinea pigs with airway eosinophilia induced by ovalbumin sensitization.ObjectiveSince ozone is known to induce tumor necrosis factor‐a (TNFa) production, we characterized the role of TNFa on eosinophil production, function, and migration in non‐sensitized and sensitized guinea pigs exposed to ozone.MethodsNon‐sensitized and ovalbumin‐sensitized (4.2 mg i.p., day 1, 3 and 5) guinea pigs were treated with 5‐bromo‐2′‐deoxyuridine (BrdU; 100mg/kg i.p., day 21) to label newly dividing cells. Animals were then exposed to air or ozone (2.0ppm, 4h) and treated with BrdU daily thereafter (50mg/kg i.p.). Some animals were given the TNFa antagonist, etanercept (3mg/kg i.p.) 3 hours before ozone exposure. Three days later, guinea pigs were anesthetized, paralyzed, and ventilated at constant volume and flow. Bronchoconstriction was measured as an increase in pulmonary inflation pressure (mmH20) in response to electrical stimulation of the distal ends of cut vagus nerves (2–25hz, 10V, 0.2msec 5sec on 60sec off). Inflammatory cells were harvested from bone marrow, blood, and lungs.ResultsOzone caused eosinophil hematopoiesis in bone marrow, recruited newly divided eosinophils to lungs, and induced airway hyperreactivity to vagal stimulation in non‐sensitized guinea pigs. Sensitization potentiated ozone‐induced airway hyperreactivity, however, eosinophil hematopoiesis and recruitment of newly divided eosinophils to lungs failed to occur. Blocking TNFa inhibited eosinophil hematopoiesis and recruitment to the lungs in non‐sensitized animals, loss of eosinophils further potentiated ozone‐induced airway hyperreactivity. Blocking TNFa had no effects in sensitized guinea pigs exposed to ozone.ConclusionsThese data demonstrate a novel protective role for eosinophils in vagally‐mediated bronchoconstriction in non‐sensitized animals. In non‐sensitized guinea pigs TNFa mediates ozone induced eosinophil hematopoiesis and subsequent recruitment of newly divided eosinophils to lungs where they inhibit vagally mediated bronchoconstriction. These beneficial eosinophils are lost with sensitization.Support or Funding InformationHealth Effects Institute (ADF), ES017593 (ADF), HL113023 (DBJ), AR061567 (DBJ), HL124165 (DBJ)
DNA Mismatch Repair Protein Interactions on Mismatch‐Containing DNA
Authors: Dos Santos Nilse Lene Goncalves , Gupta Dipika , Heinen Christopher D 
Published: November 2023

Lynch syndrome (LS) is the most common form of hereditary colon cancer. Stemming from the inheritance of mutations in the DNA mismatch repair (MMR) genes, LS increases lifetime risk for colonic and certain extra‐colonic cancers. Unlike sporadic cancers, LS cancers have an average age of onset of 40 years‐old. MMR improves replication fidelity by recognizing and coordinating the repair of single base‐pair mismatches and small insertion/deletion loops. When deficient for MMR, cells acquire a mutator phenotype that increases the rate of mutation in other important oncogenes and tumor suppressors. This eventually leads to cancer development. The MMR pathway is composed of four main genes: MSH2, MSH6, MLH1 and PMS2. MSH2 and MSH6 proteins form a heterodimer that recognizes mismatches on DNA and recruits a heterodimer of MLH1 and PMS2. Together, they signal for Exonuclease I to remove the erroneous region on the nascent strand. Previous studies have indicated that MSH2‐MSH6 bound to ATP forms a sliding clamp on the DNA that is required for its interaction with MLH1‐PMS2. However, the nature of this interaction for downstream signaling remains elusive. Current models propose that MSH2‐MSH6 and MLH1‐PMS2 form a quaternary structure on DNA and function as a unit to promote repair, but there is no direct evidence for this structure. We therefore explored the hypothesis that the two heterodimers form stable quaternary structures that function as a unit to signal excision. Using an in vitro system with biotinylated mismatch‐containing DNA and streptavidin coated magnetic beads, we isolated MMR protein‐DNA complexes and studied their interaction and stability. We confirmed that MSH2‐MSH6 can form sliding clamps on mismatch‐containing DNA in the presence of ATP. We next found that while initial loading of MLH1‐PMS2 on mismatch‐containing DNA requires these MSH2‐MSH6 sliding clamps, MLH1‐PMS2 remains stably bound to DNA even after MSH2‐MSH6 has dissociated. We also found that MSH2‐MSH6 is less stable on DNA in the presence of MLH1‐PMS2. These results suggest that MSH2‐MSH6 loads MLH1‐PMS2 onto mismatch‐containing DNA and that a stable, quaternary unit may not necessarily be required. These studies will improve our knowledge of the mechanism by which MMR maintains genomic stability and, ultimately, improve prevention and treatment of MMR‐defective cancers.Support or Funding InformationConnecticut Institute for Clinical and Translational Science (CICATS)
Development of Physiologically Relevant Methods for Assessing Inhibition of Glycoprotein Virulence Factors by Small Molecules in Human Pathogen Campylobacter jejuni
Authors: Zamora Cristina Y. , De Schutter Joris W. , Chen Kelly W. , Griffith Linda G. , Imperiali Barbara 
Published: November 2023

Campylobacter jejuni is a major cause of gastroenteritis, often resulting in death of the young, elderly and immunocompromised. Campylobacteritis also may result in complications leading to autoimmune and neurological disorders such as Guillain‐Barre syndrome. In this organism, a consistent structure‐function relationship has emerged in recent years: the importance of N‐linked protein glycosylation for bacterial pathogenic and colonization behaviors in avians and mammals. However, the biochemical roles and molecular mechanisms of C. jejuni N‐glycans in the infection of human intestinal epithelium are not understood. Our laboratory has developed small molecule inhibitors of critical biosynthetic enzymes in the N‐glycosylation pathway (pgl pathway), acting on their respective targets with up to nM affinity in vitro. Assessing the efficacy of small molecule inhibitors of protein glycosylation in vivo with microaerophilic Gram‐negative organisms has proven difficult. To this end, we have pursued several efficient, quantitative and broadly applicable strategies for assessing glycosylation inhibition and any downstream effects on bacterial pathogenicity. We have developed conditions for C. jejuni culture in the presence of small molecule inhibitors and subsequent quantification of protein glycosylation via immunoassay. In addition, inhibitors of biosynthetic enzymes in the pgl pathway are also assessed in vivo utilizing E. coli strains expressing C. jejuni protein glycosylation pathway enzymes, providing additional insight into the effects of outer membrane composition on inhibitor permeability. Lastly, in collaboration with the Griffith lab, we are developing methods for the characterization of C. jejuni pathogenicity using a unique co‐culture platform bearing polarized human gut epithelial monolayers comprised of enterocyte (Caco2), mucin‐producing goblet cells (HT29‐MTX), and immune cells (dendritic cells). This “gut chip” platform, providing histological, fluorometric and immunological readouts, will be critical for monitoring the adhesion and invasion of C. jejuni strains with attenuated glycosylation patterns and can be easily be turned toward the investigation of pathogenicity in other organisms. These multifaceted approaches will provide useful molecular detail and phenotypic characterization toward the further development of this new class of inhibitors and a greater understanding of mechanisms behind pathogenesis.Support or Funding InformationThis work is supported by the National Institutes of Health (R01‐‐GM097241 and R03‐MH096549 to B.I.) and the Belgian American Exchange Fellowship.
Antioxidant Capacity of Selected Vegetables, Nuts and Berries and Their Effects on Interferon Gamma Produced By Salmonella Typhi Parasitized Female Albino Rats
Authors: AKANDE IDOWU SULE , OLA MOJOYINOLA JOANNA , SALAKO FAITH OLUGBEMILEKE 
Published: November 2023

Almost all synthetic drugs possess adverse side effects in human body. Natural processes by which the immune system can be improved to combat diseases apart from vaccination remain the best options of preventing and terminating diseases. We investigated the antioxidant capacity and effects of selected vegetables, nuts and berries (Vernonia amygdalina, Telfairia occidentalis, Amaranthus hybridus, Juglans regia, Anacardium occidentale, Elaeis guineensis, Fragaria ananassa and Vitis vinifera) on antioxidant system and potentials to improving the immune system responses in a typhoid fever model disease in rat. Extracts of selected vegetables, nuts and berries obtained by the use of the sohxlet extractor were orally pre‐administered to adult female albino rats (n=30), of Wistar strain weighing between 120 to 190 g and divided into 6 groups, before inoculation of Salmonella typhi. Widal test was done to ascertain typhoid induction. Blood samples were collected and used for haematological parameters count and determination of oxidative stress biomarkers activities (GSH, CAT, SOD and MDA), liver and kidney function biomarkers activities using automated analyzer and concentration of interferon gamma (INF γ) using Enzyme linked immunosorbent assay (ELISA). Salmonella typhi colony count was done using faecal samples. Phytochemical screening and the antioxidant activities of the extracts were also determined. Pre‐administration of the extracts maintained steady weight of the parasitized albino rats. Extracts of berries and nuts had the highest in vitro antioxidant capacity compared to the controls. Vegetables improved quality of red cell indices. In vivo antioxidant assay indicated a statistically significant value (p≤0.05) for the extracts of nuts and berries in the levels of GSH compared to the controls. There were no statistically significant difference (p≥0.05) in the levels of liver and kidney function biomarkers between the test and the control groups. Nuts and berries reduced S.typhi colonies and recorded lowered production of INF γ compared to other groups. We conclude that the combined consumption of vegetables, berries and nuts improve immune responses and reduction of oxidative stress.Support or Funding InformationSELF SPONSORED
Anti‐inflammatory effect of caffeine by regulating NF‐κB activation in murine macrophage
Authors: Hwang Ji‐Hyun , Koh Eun‐Jeong , Lee Yeon‐Joo , Chio Jia , Song Ji‐hyeon , Seo Young‐Jin , Lee Boo‐Yong 
Published: November 2023

Caffeine is white crystalline xanthine alkaloid and found in the seeds, the coffee plant and the leaves of the tea bush. In this study, we determined whether caffeine exerts anti‐inflammatory effects on lipopolysaccharide (LPS)‐induced inflammation in RAW264.7 cells.To examine the effects of caffeine on LPS‐induced inflammation, RAW 264.7 cells were treated with various concentrations of caffeine in the presence or absence of LPS.Our data showed that caffeine decreased the LPS‐induced inflammatory mediator, nitric oxide (NO). Caffeine treatment also reduced the expression of pro‐inflammatory genes inducible nitric oxide synthase (iNOS), cyclooxygenase‐2 (COX‐2), interleukin (IL)‐3, IL‐6 and IL‐12, and decreased IL‐6 secretion and phosphorylated p38MAPK expression in LPS‐treated RAW264.7 cells. Caffeine inhibited the nuclear translocation of nuclear factor κB (NF‐κB) via IκBα phosphorylation. In addition, caffeine inhibited LPS‐induced NO production in zebrafish.Caffeine may inhibit LPS‐induced inflammatory responses in murine macrophage by regulating NF‐κB activation and MAPK phosphorylation.
Enhanced carotid body chemoreflex function drives respiratory‐sympathetic coupling in systolic heart failure
Authors: Del Rio Rodrigo , Marcus Noah J , Schultz Harold D 
Published: November 2023

Enhanced carotid body (CB) chemoreflex sensitivity in systolic heart failure (HF) has been linked to oscillatory breathing patterns and autonomic imbalance. Importantly, breathing pattern alterations and heightened chemoreflex‐mediated sympathetic nerve activity are both associated with higher morbidity and mortality in HF. Therefore, the objective of this study was to determine whether CB denervation (CBD) would improve respiratory stability and decrease sympathetic drive in HF. In rabbits with pacing‐induced HF, we measured resting breathing and renal sympathetic nerve activity (RSNA), before and after CBD. In addition, we assessed respiratory‐sympathetic coupling using power spectral analysis and the magnitude of the peak coherence function between tidal volume (Vt) and RSNA frequency spectra. Minute ventilation and RSNA responses to acute hypoxia were significantly augmented in HF compared to controls and were abolished by CBD. Resting RSNA was greater in HF compared to control animals (43 ± 5% max vs. 23 ± % max, p<0.05). HF animals after CBD displayed resting RSNA levels similar to control animals. HF animals displayed altered breathing patterns characterized by oscillatory breathing and increases in the incidence of apneas/hypopneas. Remarkably, CBD totally normalized oscillatory breathing patterns in HF animals. Peak coherence between RSNA and Vt signals was increased in HF animals (control 0.49 ± 0.05; HF 0.79 ± 0.06), and was significantly attenuated by CBD (0.59 ± 0.05, p<0.05 for all comparisons). Our data show that enhanced CB‐mediated chemoreflex drive contributes to tonic elevations in RSNA and breathing instability in HF. Additionally, a tonic increase in CB afferent discharge may also play an important role in strengthening a link between respiratory and sympathetic neural outflow in HF.Support or Funding InformationSupported by Fondecyt 1140275, NIH PO1‐HL62222 and NIH F32 HL108592‐01A1.
Learning About Physiology is PhUn at an Elementary School in Ponce, Puerto Rico
Authors: Cruz Myrella L , Hernandez Siomara , Isidro Raymond A , Hernandez Anixa , Vazquez Bethzaly , Diaz Hector , Lopez Abdon , Torres‐Reveron Annelyn , Colon Maria , Appleyard Caroline B 
Published: November 2023

Since 2010, members of the Puerto Rico Physiological Society at PHSU‐PRI have been involved in PhUn week, the annual K‐12 outreach program sponsored by The American Physiological Society. As part of the PhUn week 10th anniversary celebration, graduate students and staff from Ponce Health Sciences University ‐ Ponce Research Institute (PHSU‐PRI) took the “PhUn” to the elementary school students at Academia Santa María Reina in Ponce, Puerto Rico.AimTo assess the impact of a PhUn week activity in 3rd and 6th graders.MethodsA team of graduate students, staff and faculty from PHSU‐PRI organized a half‐day workshop for a group of thirty‐eight 8–11 year old students and two science teachers. The workshop consisted of three short presentations (gastrointestinal system, circulatory system and nervous system) which included integrated videos, optical illusions, experiments and demonstrations. Next, the children were divided into smaller groups to rotate through five interactive stations featuring: histology, anatomy, emulsification, a life‐size neuron model and DNA extraction. At each station the PHSU‐PRI helpers explained what the purpose of the activity was and were available to answer questions. All activities were conducted in Spanish. Pre‐ and post‐tests evaluated student learning. Data was analyzed using an unpaired Student t‐test and chi‐square test.ResultsStudents were clearly excited, demonstrated lots of enthusiasm, and were very proactive in all of the activities asking a lot of questions. A significant increase in the number of correct answers for all questions occurred following the workshop (gastrointestinal system p<0.001, circulatory system p<0.05 and nervous system p<0.001).ConclusionsShort presentations and engagement of students from 3rd and 6th grade in interactive hands‐on activities in their native language helped to significantly increase their knowledge of basic physiological concepts.Support or Funding InformationSupported in part by R25GM082406
Effect of Core Temperature during Exercise on Markers of Muscle Injury and Oxidative Stress
Authors: Starnes Joseph , Herberg Timothy , Lee Kuan‐Ting , Hixson Lindsay , Vervaecke Lauren , Goldfarb Allan 
Published: November 2023

Exercise of sufficient intensity carried out at room temperature significantly increases core temperature (Tc) in rats. In this study we tested the hypothesis that preventing the exercise‐induced rise in Tc will decrease markers of skeletal muscle injury and oxidative stress that are associated with prolonged exercise bouts. Following one week of familiarization to a motor driven treadmill in a 23°C room, male, 10‐wk‐old Sprague‐Dawley rats were assigned to a sedentary (S) group (n = 15) or to groups that ran on a treadmill for 90 min at a speed of 20 m/min up a 6° grade in either a 23°C room (23R) (n = 10) or an 8°C room (8R) (n = 9). Tc was monitored via telemetry. Blood was collected from the tail vein at rest or immediately post exercise followed by removal of gastrocnemius and plantaris muscles. An aliquot of blood was immediately acidified to stabilize oxidized (GSSG) and reduced (GSH) glutathione and these markers of oxidative stress were subsequently measured by HPLC with electrochemical detection. Serum was prepared in the remainder and used to measure lactate dehydrogenase activity (LDH) as an indicator of muscle injury. Glycogen content and additional markers of oxidative stress (TBARS and aconitase activity) were measured in skeletal muscles. Tc was unchanged from rest in 8R and increased 2.5°C to 40.5±0.2°C in 23R (P<0.05). Compared to S, serum LDH in 23R increased 105% (P<0.05) but did not change in 8R (P>0.05). Similarly, blood GSSG content and GSSG/total glutathione increased 132% and 180%, respectively, in 23R (P<0.05) and did not change in 8R compared to S. TBARS and aconitase activity in muscles were not different among groups (P>0.05). Gastrocnemius glycogen was depleted approximately 40% in both 23R and 8R compared to S (P<0.05). We conclude that elevated Tc plays a major role in aerobic exercise‐induced increases in oxidative stress and muscle injury.Support or Funding InformationSupported by UNC‐Greensboro Safrit Research Measurement Fund
Effects of intrarenal afferent stimulation by Bradykinin on Renal Sympathetic Nerve Activity: Tonic Inhibition facilitating Sodium and Water Excretion
Authors: Hindermann Martin , Ditting Tilmann , Rodionova Kristina , Loosen Sonja , Ott Christian , Schmieder Roland E , Amann Kerstin , Veelken Roland 
Published: November 2023

Bradykinin may increase renal sodium excretion by decreasing ENaC activity in tubuli. Renal afferent nerves (RANs) play an important role in the modulation of renal sympathetic nerve activity (RSNA) involved in renal sodium handling. We recently reported tonic sympatho‐ inhibitory action due to intrarenal afferent nerve stimulation by the TRPV1 agonist capsaicin. Since BK is known to augment TRPV1 effects we hypothesized that intrarenally applied BK would rather inhibit than excite RSNA thus also facilitating sodium and water excretion by neurogenic pathways.3 groups of anesthetized rats (n=8, each) were equipped with arterial and venous catheters for blood pressure (BP) and heart rate (HR) recording and drug application; left sided renal arterial catheter for intrarenal administration (IRA) of Bradykinin (BK; group 1) or the TRPV1 agonist capsaicin (CAP, pos. control; group 2) to stimulate RANs (CAP 3.3, 6.6, 10 and 33*10−7M, 10μl each; BK 10*10−6M, 20μl and BK 10*10−5 M; 2.5, 5, 10μl at 30, 45, 60, 75min). Normal saline (IRA NS) served as neg. control (group 3); right sided electrode for RSNA recording; After 105min the NK1‐receptor blocker RP67580 (10*10−3M, 15μl). IRA BK and IRA CAP decreased RSNA from 4.2±0.8 to 1.3±0.2μV*sec (BK, P<0.01) and 3,6±0,5 to 0.9±0.2μV*sec (CAP, P<0.01) while maximum inhibition was reached within 70 minutes. IRA NS had no effect. Tonically suppressed RSNA (CAP & BK group) was transiently but completely unmasked by systemic (IV) administration of the NK1‐blocker (1.6±0.5 to 8.6±2.9μV*sec; P<0.01 (BK); 1.0±0.2 to 6.1±1.5μV*sec; P<0,01 (CAP)). IRA BK was associated with short lived (1–2 sec) increases of RSNA (up to 13.3±2.4μV*sec; P<0.01). The effect of intrarenal BK was similar to CAP. Thus, the net effect of intrarenal stimulation of RANs by BK is sympatho‐inhibitory in nature. The similarity of NK1‐blocker effects indicates a common final pathway of intrarenal afferent stimulation. Bradykinin by inducing renal sympathodepression rather increases sodium and volume excretion likely enhancing the effect of salt‐sensitive inhibition of ENaC activity by bradykinin in the kidney.Support or Funding InformationDeutsche Forschungsgemeinschaft
Effects of Electronic Cigarette Vapor on Body Mass, Food Intake, and Body Composition
Authors: Breit Matthew , Hoskinson Hannah , Pitzer Chris , Wu Zhongxin , Bryner Randall , Olfert I.M 
Published: November 2023

Nicotine and cigarette smoking is known to promote weight loss and suppress appetite. Since becoming available in 2007, the use of electronic cigarettes (E‐cig) has increased dramatically in the US, however there are still very few studies that examine the long‐term consequences of e‐vapor, particularly in the context of appetite regulation or weight management. The present study was devised to compare the effects of cigarette smoke and E‐cig vapor exposure on food intake, body weight, and body composition in mice. We hypothesized that E‐cigs would elicit similar changes on body mass, adiposity, and food intake as conventional cigarettes (i.e. 3R4F reference cigarette). Female C57BL/6 mice were exposed to filtered room air (n=15), mainstream smoke from 3R4F reference cigarette (n=15), or cappuccino E‐cig vapor (n=15). We report assessments in body mass, food intake, and body composition following daily exposure (4 h/d, 5d/wk) for up to 6 months. Food and water were administered ad libitum. 3R4F, E‐cig and control mice increased body mass by 15%, 30%, and 31%, respectively, over 6 months. 3R4F mice had 15–16% lower body mass (24.9±0.55 g, p<0.01) compared to E‐cig (28.2±0.77 g) and controls (27.7±0.72 g). 3R4F exposed mice also exhibited reduced total body fat (2.74±0.25 g, p<0.01) compared to E‐cig (4.10±0.42 g) and controls (4.18±0.40 g). E‐cig mice food consumption was significantly increased compared to 3R4F (12.4±0.8 vs 9.5±0.7 g, respectively; p<0.05) but not significantly different compared to controls (12.4±0.8 vs 10.5±0.8 g, respectively, p=0.12). Unlike conventional cigarettes, we found that our E‐cig exposed mice did not elicit reductions in total body or adipose mass. This suggests the effects of E‐cig may not be the same as that occurring with traditional tobacco cigarettes, or that the exposure to nicotine and/or other chemicals in the E‐cig liquid elicits a different response on appetite or feeding behavior. Further studies are needed to evaluate the effect that flavorings and/or the compounds produced in E‐cig vapor exert on metabolism and the hypothalamic appetite neurosystems.Support or Funding InformationNIH Grant P20GM103434 (West Virginia IDeA Network for Biomedical Research Excellence) and Marshall‐WVU Health Initiative Award