bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of the Innate Immune System in the Development of Hypersensitivity Pneumonitis
Authors: Ocasio-Rivera Marinel , Elmore Jessica , August Avery 
Published: April 2020

Hypersensitivity pneumonitis (HP) is an extrinsic allergic alveolitis disease that is constantly affecting the farmers. It is triggered by the continuous exposure of environmental antigens, specifically antigens that grow in hot humid conditions in hay like Saccharopolyspora rectivirgula (SR). While a role of T cells has been established in the development of this diseases, the role of the innate immune system is still largely unknown in the development of lung inflammation leading to HP. To study this disease, we used a mouse model of HP, induced by SR, along with Rag−/− mice which only have an innate immune system and lack an adaptive immune system (and thus have no T cells). We hypothesized that the development of Hypersensitivity pneumonitis requires the presence of T (and B) cells, at the same time, there will be a lower percentage and number of inflammatory cells in the lungs of Rag−/− mice upon exposure to SR. WT and Rag−/− mice were exposed to SR. Lungs, spleen and lymph nodes where collected to analyze their response. We examined the percentage and number of myeloid and Innate Lymphoid Cells (ILC), as well as their ability to produce cytokines. We found that there was no significant difference in the number of Innate Lymphoid cells and myeloid cells between SR‐exposed WT and Rag−/− mice. These results may be due to the low concentration of bacteria used for these experiments. In future experiments, we propose to use a higher concentration of SR to induce inflammation.Support or Funding InformationThis work was supported in part by grants from the NIH‐AI38570, NIH‐AI20701, and NIH‐AI129422. NIH‐NIGMS #2R25GM096955 (RISE). VIP‐Veterinary Investigation Program.
Canagliflozin provides cardioprotection and renoprotection against isoprenaline‐induced oxidative stress by stimulating AMPK‐Akt‐eNOS‐NO signaling axis
Authors: Hasan Raquibul , Lasker Shoumen , Hasan Ahasanul , Zamila Mushfera , Zerin Farzana , Chowdhury Faizul Islam , Rahman Md. Mizanur , Khan Ferdous , Subhan Nusrat , Alam Md. Ashraful 
Published: April 2020

The antidiabetic drug canagliflozin, a SGLT2 inhibitor, has been reported to possess protective effects against ischemia‐reperfusion and chemically‐induced cardiac and renal injuries. However, to our knowledge, no studies have investigated the protective effects of canagliflozin in isoprenaline (ISO)‐induced cardiac and renal oxidative damage – a model mimicking sympathetic nervous system (SNS) overstimulation‐evoked organ injuries in humans. Therefore, we investigated effects of canagliflozin in ISO‐induced cardiac and renal oxidative stress, and their underlying molecular mechanisms. Our tissue biochemistry, histology, and Western blotting data showed that ISO administration inflicted pro‐oxidative, pro‐inflammatory and pro‐apoptotic changes in the heart and kidney tissues. In contrast, treatment with canagliflozin at 5 mg/kg body weight attenuated levels of cardiac and renal oxidative stress markers including malondialdehyde (MDA), advanced protein oxidation product (APOP), myeloperoxidase (MPO) and nitric oxide (NO), and restored levels of endogenous antioxidant molecules such as catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH) that were depleted in ISO‐treated rats. Western blot analysis revealed that canagliflozin increased activity of anti‐oxidant/anti‐inflammatory proteins such as AMP‐activated protein kinase (AMPK), Akt and eNOS, and decreased pro‐oxidative/pro‐inflammatory proteins including iNOS and NADPH oxidase isoform 4 (NOX4). Protein expression analysis further revealed that ISO increased the ratio of pro‐apoptotic/anti‐apoptotic protein (Bax:Bcl‐2) expression, which was significantly reduced by canagliflozin treatment. Our histological examination demonstrated that in the heart and kidney tissue sections, canagliflozin attenuated ISO‐induced histopathological changes, including inflammatory cell infiltration, collagen deposition, and fibrosis. Consistent with our biochemical data, canagliflozin augmented heart and kidney functions in ISO rats, further supporting a protective role of this drug in ISO‐induced oxidative stress. In summary, we show that canagliflozin produces cardioprotective and renoprotective actions via suppression of iNOS, NOX4 and Bax, and activation of AMPK‐Akt‐eNOS‐NO signaling axis.Support or Funding InformationThis work was supported by a start‐up grant from the Mercer University College of Pharmacy to Dr. Raquibul Hasan and a research grant from North South University to Dr. Md Ashraful Alam
A Novel Parkinson’s Disease Model: PINK1/PARKIN Double‐Knockout Rats
Authors: Almikhlafi Mohannad A. , Lamberty Benjamin G. , Totusek Steven A. , Fox Howard S. , Stauch Kelly L. 
Published: April 2020

IntroductionAnimals are important tools to study pathological changes, behavioral abnormalities, and therapeutics in Parkinson’s disease (PD), which is characterized by loss of dopaminergic neurons in the substantia nigra (SN). Loss‐of‐function mutations in PTEN‐induced putative kinase 1 (PINK1) and Parkin, mitophagy pathway genes are linked to autosomal recessive PD in humans; however, deficiency does not lead to PD symptoms or affect dopaminergic neurons in the SN in mice. In rats, loss of PINK1, but not Parkin, leads to progressive neurodegeneration in the SN and motor symptoms in a subset of animals. To try to obtain a more robust model of PD, we generated a PINK1/Parkin double‐knockout (PP‐DKO) rat model.HypothesisWe hypothesized that PP‐DKO have mitochondrial dysfunction leading to a loss in dopaminergic neurons in the SN causing motor deficits.MethodsUsing PP‐DKO rat model, mitochondrial bioenergetics were measured by seahorse‐XF96, neuronal quantification by immunohistochemistry and stereology, and behavioral assessment examining motor coordination, bradykinesia/agility, hindlimb strength, and gait.ResultsStriatal mitochondrial bioenergetics displayed dysfunction at 3‐month old rats. Maximal respiration and spare respiratory capacity were decreased. PP‐DKO at 6 and 8 months showed a 23% and 45% reduction in dopaminergic neurons in the SN; respectively. Also, a 30% reduction in the number of neurons was found in the ventral tegmental area at the 8 months. Motor coordination was assessed by rotarod, which showed a reduction in the latency to fall at 6‐ and 9‐months old rats. Bradykinesia and agility were tested by pole test that showed an increase in the time the rat required to turn and to walk down the pole at 6‐ and 9‐months old rats. Cylinder test showed a significant reduction in hindlimb strength when rearing frequency was measured at 6, and 8 months of age. Finally, gait abnormalities were also present at 8 months including reduction in hindlimb step length, reduction in fore‐ and hindlimb step pressure alongside with an increase in step angle.ConclusionPP‐DKO is a novel genetic model with reproducible neuropathology and motor abnormalities of PD that will help researchers to study the mechanisms by which recessive genes produce PD as well as testing preventative and potential therapeutic paradigms.Support or Funding InformationThis research was funded by Michael J. Fox Foundation for Parkinson’s research grant #15288
The Plasma Membrane Translocation of HspA1A, a Stress Inducible 70‐kDa Heat Shock Protein, Depends on its Interaction with Membrane Lipids
Authors: Smulders Larissa , Nikolaidis Nikolas 
Published: April 2020

HspA1A is a stress‐inducible seventy‐kilodalton heat shock protein (Hsp70). This protein is a molecular chaperone that plays important roles in cell survival. Normally, HSPA1A functions within the cytoplasm. Yet, in stressed and cancer cells HspA1A also localizes at the plasma membrane (PM). In cancer cells, in particular, the presence of HspA1A at the cell surface allows the tumor to increase invasiveness and develop resistance to radiation therapy. Therefore, blocking this protein from being at the surface of tumors is a promising therapeutic. However, the translocation pathway of HspA1A to the PM remains puzzling, because this protein lacks membrane localization signals. Based on the fact that HspA1A interacts with lipids, including phosphatidylserine (PS) and several mono‐phosphorylated phosphoinositides (PIPs), we hypothesized that the interaction of HspA1A with these lipids allows the chaperone to localize at the PM. To test this hypothesis, we subjected different cell lines to mild heat‐shock and the PM‐localized HspA1A was quantified using confocal microscopy and cell surface biotinylation. These experiments revealed that HspA1A’s membrane localization and embedding increased during recovery from non‐apoptotic heat‐shock. Next, we selectively reduced PS, PI(4)P, and PI(3)P targets by co‐transfecting HspA1A with known PS‐, PI(4)P‐, and PI(3)P‐ biosensors, and determined that HspA1A’s membrane localization was greatly reduced in all three cases. In contrast, the reduction of PI(4,5)P2 availability by overexpression of the PLCδ‐PH biosensor had minimal effects on HspA1A’s PM‐localization. Additionally, we manipulated the cellular lipid content using ionomycin, a calcium ionophore that activates PLC, and phenylarsine oxide (PAO), a PI4‐Kinase inhibitor, using several lipid‐biosensors as positive and negative controls. These experiments revealed that the PM localization of HspA1A was unaffected by ionomycin, but was greatly reduced in the presence of PAO, corroborating the findings obtained by the lipid‐biosensors on the importance of specific lipids in the PM translocation of HspA1A. Collectively, these findings strongly support the notion that HspA1A’s PM localization and anchorage is a complex lipid‐driven phenomenon controlled by the binding of the chaperone to endosomal and plasma membrane PS, PI(4)P, and PI(3)P. Our findings provide the basis for interventions that block HSPA1A’s translocation to the tumor cell’s PM allowing the cell to remain sensitive to radiation therapy and decrease its invasiveness.Support or Funding InformationThis project was supported by funds from NIH
Sex Differences in Response to Acute Sympathetic Activation During Steady State Hypoxia
Authors: Jacob Dain W. , Harper Jennifer L. , Ott Elizabeth P. , Ivie Clayton L. , Limberg Jacqueline K. 
Published: April 2020

BackgroundActivation of the sympathetic nervous system causes vasoconstriction and a reduction in peripheral blood flow. This sympathetically‐mediated vasoconstriction may be attenuated during hypoxia to maintain oxygen delivery – termed sympatholysis. However, hypoxic sympatholysis was previously shown to be absent in humans. A limitation of prior work was the failure to directly examine this response in women. Given young women exhibit an increase in blood flow during hypoxia, we hypothesized hypoxic sympatholysis would be present in young women but absent in young men.MethodsBlood pressure (BP, finger photoplethysmography) and forearm blood flow (FBF, venous occlusion plethysmography) were assessed in healthy young men (n=9, 26±1 yrs) and women (n=10, 24±1 yrs). Subjects completed two trials consisting of a 2‐min cold pressor test (CPT) during baseline normoxia (0.21 FiO2, 98±0% SpO2) and following 3 min of steady‐state hypoxia (0.11±0.01 FiO2, 82±1% SpO2). FBF was normalized for BP (forearm vascular conductance, FVC). A change in FVC from steady‐state during the last 1‐min of CPT was calculated (ΔFVC). The difference in ΔFVC between normoxia and hypoxia trials was used as an index of hypoxic sympatholysis.ResultsIn men, ΔFVC did not differ between normoxia and hypoxia (ΔFVC Normoxia: −0.30±0.45, Hypoxia: −0.77±0.41 mL/dL/100mmHg/min; p=0.46). In contrast, in women ΔFVC during normoxia (−0.70±0.27 mL/dL/100mmHg/min) was attenuated during hypoxia (+0.48±0.46 mL/dL/100mmHg/min; p=0.04) – indicating sympatholysis. The magnitude of hypoxic sympatholysis was greater in women than in men (Men: −0.46±0.38, Women: +1.18±0.39 mL/dL/100mmHg/min; p<0.01).ConclusionYoung women attenuate sympathetically‐mediated vasoconstriction during steadystate hypoxia, whereas men do not. In other words, hypoxic sympatholysis is present in young women, but absent in young men. These data advance our understanding of sex‐related differences in hypoxic vascular control.Support or Funding InformationFundingNIH HL130339
The Effect of Preterm Birth and Recurrent Laryngeal Nerve Lesion on Palatopharyngeal Arch Function During Feeding
Authors: Edmonds Chloe Elise , Catchpole Emily A. , Mayerl Christopher J. , German Rebecca Z. 
Published: April 2020

Feeding in infant mammals requires the precise coordination of multiple oropharyngeal structures, including the palatopharyngeal arch. During a typical swallow, the activity of the palatopharyngeus muscle produces constriction of the arches and lowers the soft palate, which may be responsible for flipping of the epiglottis to cover the airway. Most research on the role of the palatopharyngeal arches in swallowing has been limited to pharyngeal manometry, which provides insight into the relative pressures in the oropharynx during swallowing. Studies using manometry in preterm infants, or in those with iatrogenic sequelae such as recurrent laryngeal nerve (RLN) damage, suggest differences in function, but not on how the structures in the oropharynx move to contribute to those changes in function. In this study, we assessed palatopharyngeal arch kinematics during feeding by using our validated infant pig model to determine the impact of birth status (preterm versus term), lesion status (lesioned RLN versus intact) and their interaction on feeding performance. We placed tantalum radio‐opaque beads into relevant anatomical structures of 16 infant pigs, including the palatopharyngeal arches, the tongue, the hard and soft palate, and the nose. We recorded feeding at both seven and 17 days postnatal via biplanar high‐speed videofluoroscopy (100fps) across a total of 584 swallows. Using XMALab, we tracked the three‐dimensional movement of the arches relative to a rigid body comprised of the markers in the hard palate and the nose. We then used custom MATLAB code to calculate the three‐dimensional excursion of the arches during a swallow, as well as the timing of constriction initiation, and the point of maximal constriction during a swallow. We found that preterm infants had more variable arch excursion than term infants, and RLN lesion increased excursion for both term and preterm infants although there were minimal differences in arch excursion within an age between term and preterm infants. Term infants also reached maximal arch constriction later than preterm infants, most likely due to their larger arch excursion and larger bolus volume. Lesion infants, both term and preterm, also had delayed maximal arch constriction during swallows, although day 17 term lesion infants reached maximal constriction earlier than term day 17 infants. Lesion resulted in delayed initiation of arch constriction, which did not change with age, although older term infants exhibited later arch constriction initiation than older preterm infants. Our results show that preterm birth and RLN lesion have distinct yet pervasive effects on infant feeding. Altered feeding performance in these neurologically compromised infants may be due in part to changes in the activity of the palatopharyngeal arches.Support or Funding InformationNIH R01HD088561
Effect of Histamine‐Receptor Antagonism on the Acute Inflammatory Response to Aerobic Cycling Exercise
Authors: Mangum Joshua , Needham Karen , Sieck Dylan , Minson Christopher , Halliwill John 
Published: April 2020

Blood flow to previously exercised muscle remains elevated for up to two hours following exercise, in response to activation of histamine receptors. Histamine also plays a significant role in the inflammatory response, increasing capillary permeability and allowing circulating cells to move in and out of tissues. Following a novel bout of exercise, there is typically an acute inflammatory response that resolves within 24–48 hours. Therefore, the purpose of this experiment was to determine if histamine receptors contribute to the acute inflammatory response following aerobic exercise in untrained individuals. We hypothesized that histamine‐receptor antagonism would decrease the inflammatory response to novel aerobic exercise. Six untrained volunteers (2F, 4M) completed 60 min of stationary cycling at 60% of their VO2peak. Volunteers completed the exercise twice, in random order, after placebo or blockade (combined oral H1/H2 histamine‐receptor antagonism with 540 mg fexofenadine and 300 mg ranitidine). Venous blood samples were collected prior to exercise and at 0, 6, 12, 24, and 48 hours after exercise. Flow cytometry (Beckman, Gallios) was utilized to quantify cell populations. A multiplex cytometric bead assay (LEGENDplex, Biolegend) was used for cytokine analysis and quantification. Following exercise, total circulating leukocytes increased from 1.70×106 ±0.29 to 3.08×106±0.58 in placebo (p<0.05) and 1.92×106±0.28 to 3.44×106±0.43% in blockade (p<0.01). Relative values of neutrophils increased from 33±1.5% to 46±1.6% in placebo (p=.13) and 36±5% to 56±2% in blockade (p<0.05). On average, total circulating leukocytes and neutrophils remained more elevated following exercise with blockade vs placebo (p<0.01). There was no effect of blockade on monocyte sub‐populations vs placebo. Following exercise, pro‐inflammatory cytokine MCP‐1 increased from 150±18pg/ml to 172±20pg/ml in placebo (p=0.18) and 151±20pg/ml to 192±13pg/ml in blockade (p<0.05). Similarly, pro‐inflammatory cytokine IL‐18 increased following exercise from 34±12pg/ml to 39±14pg/ml in placebo (p=0.21) and 35±20pg/ml to 58±13pg/ml in blockade (p<0.05). On average, MCP‐1 and IL‐18 remained more elevated following exercise with blockade vs placebo (p<0.05). Contrary to our hypothesis, the pattern of the acute inflammatory response to aerobic exercise appears to be augmented, not blunted, with histamine receptor antagonism. These data suggest that histamine receptor activation may play a complicated role in the acute inflammatory response to aerobic exercise.Support or Funding InformationSupport provided by NIH grant HL115027, AHA 17GRNT33660656, and The Eugene & Clarissa Evonuk Memorial Graduate Fellowship
Inhibiting Heptosyltransferase to Combat Gram‐Negative Bacterial Infections
Authors: Wang Alvin , Castro Colleen , Taylor Erika 
Published: April 2020

Lipopolysaccharides (LPS) embedded in the outer membrane of Gram‐negative bacteria are known to enable antibiotic resistance by providing protection from hydrophobic antibiotics and assisting biofilm development. One of the key enzymes for synthesizing LPS is heptosyltransferase I (HepI), which catalyzes the reaction of ADP‐L‐glycero‐D‐manno‐heptose (ADP‐heptose) with Kdo2‐lipid A, a precursor of LPS. Previous studies have shown that HepI deficiency in bacteria results in increased susceptibility to antibiotics and host immune response. Here, we use molecular docking analysis to obtain binding affinity calculations of 419 natural product ligands provided by the National Cancer Institute (NCI) with HepI as the receptor. Docking calculations were performed with AutoDock Vina with 200 simulations per ligand. 118 ligands were found to have an average binding affinity calculation higher than that of ADP‐heptose. Selected ligands are being investigated for in vitro inhibition of HepI through kinetic analyses using a coupled assay system where ADP, a product of the heptose transfer reaction, is detected using NADH enzyme‐linked photometric assay. Potent HepI inhibitors will be further investigated as novel candidates for antimicrobial development.Support or Funding InformationThis project is supported by from Wesleyan University and the National Institutes of Health (1R15AI119907‐01).
SLC25A34 regulates bioenergetic metabolism in the murine liver
Authors: Roy Nairita , May Meredith , Delgado Evan Ryan , Alencastro Frances , Wilkinson Patrick David , Smyers Mei , Reynolds Michael John , Shiva Sruti , Duncan Andrew Wayne 
Published: April 2020

Background and RationaleLiver regeneration and diseases associated with altered mitochondrial metabolism, including NAFLD, are associated with alterations in ploidy. Many genes that regulate mitochondrial metabolism are also reported to alter hepatic polyploidy. SLC25A34 encodes an uncharacterized inner mitochondrial membrane protein, with a novel role in liver polyploidy. Interestingly, dysregulated Slc25a34 expression has been reported in numerous studies, which are all characterized by metabolic dysfunction, particularly altered glucose metabolism and fatty acid metabolism. We now hypothesize that SLC25A34 regulates various aspects of liver metabolism.ResultsIn the current study, SLC25A34 was over expressed or knocked down in primary hepatocytes harvested from adult C57BL/6 mice and subsequent effects on different metabolic phenotypes were studied. Downregulation of SLC25A34 significantly increased the lipid droplets with a concurrent increase in expression of key players of fatty acid metabolism (Cpt1A, Srebf1, Acly). Maximal mitochondrial respiration and spare respiratory capacity were significantly elevated, possibly attributing to the increased levels of lipid droplets. Also, basal mitochondrial respiration and ATP‐linked mitochondrial respiration were significantly increased, accompanied by increased expression of regulators of mitochondrial biogenesis (PGC‐1 alpha, PGC‐1 beta, Prc and Tfam). In contrast, overexpression of SLC25A34 decreased expression of Cpt1A, Srebf1, Acly, but had no effect on lipid droplets. Unexpectedly, SLC25A34 overexpression also increased maximal mitochondrial respiration and spare respiratory capacity, as well as non‐mitochondrial respiration. Further, effect on energy intermediates (ADP, ATP and their ratio) and hepatocyte proliferation were studied. SLC25A34 depletion raised the ADP/ATP ratio and decreased hepatocyte proliferation, whereas overexpression of SLC25A34 decreased the ADP/ATP ratio and increased proliferation. Furthermore, SLC25A34 manipulation altered fatty acid oxidation and glycolysis functionally in primary hepatocytes as determined using the seahorse extracellular flux analyzer. Preliminary in‐vivo studies utilizing both whole‐body and liver‐specific SLC25A34 knockout mice indicate similar bioenergetic changes upon SLC25A34 deletion.ConclusionThe data suggest that SLC25A34 is a key regulator of bioenergetic metabolism where it is involved in metabolic homeostasis and that modulation of SLC25A34 creates distinct metabolic phenotypes in the primary hepatocytes.Support or Funding InformationThis study is supported by NIDDKR01DK103645 and UPP Academic Foundation awarded to Dr. Andrew Wayne Duncan.