bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cellular NAD+, fibroblast senescence and pulmonary fibrosis
Authors: Liu Tianju , Rinke Andrew E. , Wang Jing , Phan Sem H. 
Published: April 2020

Aging is a risk factor in fibrotic interstitial lung diseases, including idiopathic pulmonary fibrosis (IPF). Cellular senescence is observed in IPF and animal models of lung fibrosis along with telomere dysfunction, although the potential differential pathogenic significance of their cell type specific localization is unknown. Removal of senescent cells ameliorates fibrosis in animal models and are considered as potential therapeutic approaches. However the pathogenic role of aging and/or cellular senescence in the development of lung fibrosis are not fully understood. Declining cellular nicotinamide adenine dinucleotide (NAD+) levels as seen in aging, may impair the activity of senescence suppressor Sirt1, an NAD+‐dependent deacetylase, hence boosting the levels of NAD+ have been proposed to delay or inhibit aging related illnesses and improved longevity. To elucidate the role of NAD+ in cellular senescence in pathogenesis of pulmonary fibrosis, we investigated the impact of increasing or reducing NAD+ levels on bleomycin (BLM)‐induced mouse pulmonary fibrosis by supplementation with nicotinamide mononucleotide (NMN) by i.p injection, or nicotinamide phosphoribosyltransferase (Nampt) deficiency, respectively. The latter was induced by treating transgenic mice bearing the floxed Nampt and Col1a2‐CreERT transgenes with tamoxifen, resulting in mesenchymal cell specific Nampt deletion. The results showed that pre‐treatment of NMN injection before BLM injury significantly reduced lung myofibroblast differentiation as manifested by decreased Acta2 mRNA, which was accompanied by decreased numbers of senescent type II alveolar epithelial cells (SPC+/p16+), and BM‐derived monocytic myeloid cells. In contrast, deletion of Nampt in mesenchymal cells with consequent reduction of NAD+ levels caused increased myofibroblast differentiation, and more severe lung fibrosis measured by lung hydroxyproline and histology after BLM injury when compared to the response in wild type animals. In contrast to wild type cells, Nampt‐deficient lung fibroblasts exhibited elevated expression of p16, and senescence‐associated secretory phenotype (SASP) cytokines, including TNFα, IL‐1β, and IL‐6. Notably enhanced recruitment of BM‐derived myeloid cells into BLM‐injured lung was also observed. These findings suggest that NAD+ may play a significant role in prevention of cellular senescence and protection from pulmonary injury/fibrosis.Support or Funding InformationThis study is supported by NIH grants HL112880 and HL 138417.
Identification of Allosteric Modifiers of Mosquito Odorant Receptor Function and Odor‐Triggered Behaviors
Authors: Iatrou Kostas , Kythreoti G , Sdralia N , Tsitoura P , Papachristos D P. , Michaelakis A , Schulz S 
Published: April 2020

Insect odorant receptors (ORs) are heteromeric ion channels each consisting of a common subunit, ORco, and one of multiple variable subunits, ORx, to which odorants acting as specific receptor agonists or antagonists bind. In cells expressing the ORco subunit alone, functional homomeric channels are formed that can be activated by specific ORco agonists. We have previously shown that mosquito repellents that inhibit odor‐specific responses of multiple Anopheles gambiae heteromeric receptors are ORco‐specific antagonists. Additionally, the responses of heteromeric receptors induced by ORx‐agonists were significantly enhanced in the presence of an ORco‐agonist (OA), a finding suggesting that OA binding causes structural rearrangements in the liganded ORx heteromers.We are now reporting on the extension of our studies for discovery of A. gambiae ORco agonists and antagonists using an insect cell‐based ORco expression platform that allows fast screening of compound collections. Screening of a collection of volatile organic compounds (VOCs) of natural origin for relevant bioactive ligands resulted in the identification of several hits acting as ORco antagonists. The functional relevance of the identified hits has been established by in vivo repellence assays against Aedes albopictus mosquitoes, which are capable of vectoring a number of infectious agents. Nine newly identified ORco antagonists displayed significant mosquito repellent activities, with three of them causing mosquito anosmia‐like effects similar to those of equivalent doses of the widely used insect repellent DEET. Moreover, binary mixtures of the most active compounds caused stronger repellence effects relative to the single compounds, a finding suggesting the possible existence of different antagonist binding sites on ORco and functional synergies caused by allosteric interactions within the homomer and the heteromers. These results provide proof of concept that natural ORco antagonists may modify olfaction‐based mosquito behaviors in a predicted fashion. Moreover, the screening platform employed in this study yields enhanced possibilities for personal protection against mosquito‐borne infectious diseases.Support or Funding InformationSupported by OPENSCREEN‐GR “An Open‐Access Research Infrastructure of Chemical Biology and Target‐Based Screening Technologies for Human and Animal Health, Agriculture and the Environment” (MIS 5002691) funded under the Action “Reinforcement of the Research and Innovation Infrastructure” of the Operational Program “Competitiveness, Entrepreneurship and Innovation” (NSRF 2014–2020), and LIFE CONOPS (LIFE12 ENV/GR/000466) funded by the European Commission under the program LIFE + Environment Policy and Governance. We thank Asteria Karadima for the repellence test schematic.
The role of myeloid cells in lung injury‐induced muscle atrophy
Authors: Bivona Joseph J. , Crymble Hanna M. , Stapleton Renee D. , Files D. Clark , Toth Michael , Suratt Benjamin T. 
Published: April 2020

RationaleIntensive care unit acquired weakness (ICUAW) occurs in nearly 50% of patients admitted to the ICU. Patients exhibiting ICUAW have increased in‐hospital and post‐ICU mortality. ICUAW, and the associated muscle atrophy specifically, cannot be completely explained by disuse and may involve a secondary trigger to enhance the breakdown of muscle fibers. Recent work has suggested that excessive systemic inflammation may contribute to this process. We hypothesized that muscle atrophy in ICUAW may, in part, be induced by myeloid cell recruitment to muscle.MethodsC57Bl6/J mice received intratracheal (IT) instillation of lipopolysaccharide (LPS, 3 μg/g) or saline and were euthanized 3, 6, 12, 24, 72 hours thereafter. For antibody‐mediated myeloid cell depletion, 200 μg of αGR‐1, αLy6G, or isotype control antibodies were administered IP 24 hours and 1 hour prior to injury and mice were examined 24 hours post‐injury. Whole gastrocnemius muscle was analyzed using RT‐qPCR. For in vitro studies, C2C12 myoblasts were differentiated for 7 days and stimulated with LPS (1 μg/ml) to elicit an inflammatory response. Bone marrow derived macrophages (BMDMs) were differentiated with 10 ng/ml of macrophage‐colony stimulation factor for 7 days and seeded at a density of 2600 cells/cm2 (4940 cells/well) onto C2C12 myotubes after 6 days of differentiation. On day 7 of C2C12 differentiation, cocultures were stimulated as previously described. Supernatants and cell lysates were analyzed by ELISA and RT‐qPCR. Myotube diameter was measured using ImageJ.ResultsIT LPS upregulates the atrogene muscle RING‐finger 1 (MuRF1) and induces atrophy in vivo. However, this effect of LPS is not seen in cultured C2C12 myotubes alone. Depletion of neutrophils and monocytes with αGR‐1 antibody reduced MuRF1 expression in vivo. Both C2C12 myotubes and whole muscle show rapid, transient expression of myeloid chemoattractants MCP‐1 and KC (CXCL1). Cocultures of BMDMs and C2C12 myotubes enhance the expression of IL‐6 and MCP‐1 synergistically and induce C2C12 myotubes to produce TNFα.ConclusionsOur data indicate that IT LPS induces MuRF1 in vivo and our in vitro data in myotubes suggests that this effect may require myeloid cells. Further supporting this conclusion, we found that antibody depletion of myeloid cells reduced IT LPS‐induced MuRF1 expression. Moreover, expression of key myeloid cell chemoattractants are induced in muscle both in vitro and in vivo in response to LPS and addition of BMDMs to C2C12 myotubes with LPS treatment reveals synergistic increases of IL‐6 and MCP‐1 and induces C2C12 myotubes to produce TNFα. The current study implicates macrophages and neutrophils as modulators of the muscle atrophy response to following lung injury.Support or Funding InformationNIH 5R01HL143452‐02NIH 2T32HL076122‐16
Dantrolene Improves Cerebral Perfusion More than Nimodipine in a Rat Model of Cerebral‐induced Vasospasm
Authors: Roman Marie , Tirado Guillermo , Martinez Solianne , Martins Antonio , Ferrer Yancy , Morales Myrna , Crespo Maria J. 
Published: April 2020

A cerebral vasospasm (CVSP) is a potent vasoconstriction of the cerebral vasculature, and the primary cause of morbidity and mortality following a hemorrhagic stroke. The middle cerebral artery (MCA) is one of the most common locations affected by CVSPs. Experimental evidence shows that the ryanodine receptor inhibitor dantrolene may be as effective as the Ca+2 channel blocker nimodipine in reducing vasospasms in the systemic vasculature. To determine if this effect also extends to the cerebral vasculature, we used a rat model of cerebral‐induced vasospasms to investigate the effects of intravenously administered dantrolene (2.5 mg/kg) and nimodipine (1 mg/kg) on cerebral blood flow velocity in the MCA. Blood flow velocity was measured in the MCA seven days after vasospasm‐induction, using a PeriFlux 5000 Laser Doppler System. Measurements were performed 30 minutes before and one hour after either dantrolene or nimodipine administration. In addition, hemodynamic parameters (i.e., systolic, diastolic, and mean blood pressures; heart rate) were measured before and after administration of the drugs. Dantrolene decreased MCA blood flow velocity by 35% (from 364.7± 60 to 231.0 ± 34 perfusion units), whereas nimodipine reduced this parameter by only 14% (N=6, P<0.05). For both dantrolene and nimodipine, the hemodynamic parameters remained unchanged (N=6, P>0.05, when compared to results before drug administration). Our results suggest that 2.5 mg/kg dantrolene is more effective than 1 mg/kg nimodipine in reducing vascular reactivity and improving cerebral blood perfusion in the MCA, without altering systemic hemodynamic parameters. Therefore, dantrolene may provide a promising therapy for the management of CVSP and its complications.Support or Funding InformationThis work was supported by Grants from the National Institute of Health (MBRS‐RISE Grant R25GM061838), the NIMHD‐CCRHD‐RCMI Program (U54‐MD007600), and the Anesthesiology Department of the University of Puerto Rico‐School of Medicine.
Post‐exposure treatment with esomeprazole protects pregnant mice from mortality and from compromised fetal growth after exposure to chlorine gas.
Authors: Molyvdas Adam , Ren Changchun , Dunigan Katelyn , Tipple Trent , Matalon Sadis , Jilling Tamas 
Published: April 2020

Exposure to Chlorine (Cl2) and Bromine (Br2) causes significant cardiopulmonary injury to mice, rats, rabbits and humans triggering extensive systemic injury. After exposure to Br2 pregnant mice develop preeclampsia‐like symptoms and increased mortality as compared to identically exposed male or non‐pregnant female mice (Lambert et al Hypertension 2018). Heme oxygenase (HO‐1), which has been shown recently to be induced by proton pump inhibitors such as esomeprazole (ESO), has been implicated as a protective molecule against halogen inhalation induced injury in non‐pregnant animals and, additionally, against the development of symptoms in models of preeclampsia in pregnant mice.Timed pregnant C57BL/6 mice were exposed to 400ppm Cl2 for 10min at E14.5, then treated with vehicle or with 30mg/kg ESO by gavage 6h post exposure, then at every 24h thereafter. Survival and body weights were monitored until E18.5. Fetal weights were recorded at E18.5 after euthanasia. Finally, using nuclear factor (erythroid‐derived 2)–like 2 (Nrf2)‐knock out and Nrf2 competent murine transformed club cells (mtCC) we tested whether HO‐1 production was induced via Nrf2.Survival was significantly higher (P=0.0056) in Cl2 exposed pregnant mice that received ESO (88.9% survival, n=9) compared to the vehicle treated animals (29.4% survival, n=17). Maternal exposure to Cl2 severely compromises fetal growth (0.6366g±0.0666 (S.E.M.), n=5) when compared to normal fetuses (1.167g±0.0399 (S.E.M.), n=5) (P<0.0001). However, the weight of fetuses collected from Cl2 exposed pregnant mice that received ESO (0.9264g±0.0542 (S.E.M.), n=8) compared to weights of fetuses from vehicle treated animals (0.6366g±0.0666 (S.E.M.), n=5) was significantly higher (P=0.0058). Finally, maternal weight, as normalized to weight recorded preexposure, in Cl2 exposed ESO treated pregnant mice (93.64%±4.038% (S.E.M.), n=8) compared with the vehicle treated animals (81.31%±5.717% (S.E.M.), n=5) was not significantly different (P=0.1772). Additionally, we found that HO‐1 gene expression is induced in a dose dependent manner by ESO only in Nrf2‐competent cells (p<0.001).Our results suggest that ESO may be an effective countermeasure to increase maternal survival and improve fetal growth post halogen inhalation in pregnancy. Further mechanistic studies will have to explore organ/tissue specific role of HO‐1 induction in the protective effect.Support or Funding InformationThis work was supported by: 5U01ES027697 (to Tamas Jilling) and 5U01ES026458 (to Sadis Matalon)
DHHC21‐mediated α1 Adrenergic Receptor Palmitoylation Contributes to Renal Blood Flow Regulation During Sepsis
Authors: Yang Xiaoyuan (Sherry) , Zheng Ethan , Chatterjee Victor , Creasy Alexandria , Ma Yonggang , Overstreet Jonathan , Yuan Sarah Y. 
Published: April 2020

Palmitoylation is a reaction of 16‐carbon palmitic acid attachment to a cysteine residue of a protein via thioester linkage, catalyzed by a family of palmitoyl acyltransferases containing the DHHC motif. This post‐translational modification plays a critical role in regulating protein function, subcellular localization and interactions with other cellular molecules. A recent study shows that vascular α1 adrenergic receptor (α1AR) requires DHHC21‐mediated palmitoylation for its signaling activity to induce vasoconstriction. In the kidney, arterial vasoconstriction has been implicated in the development of renal hypoperfusion following sepsis. In this study, we sought to examine whether DHHC21 contributes to kidney dysfunction by affecting renal blood flow through α1AR palmitoylation. Cecal ligation puncture (CLP) was performed to induce polymicrobial sepsis in wild type and DHHC21 functional deficient (Zdhhc21dep/dep) mice. Their renal function was dynamically assessed based on tracer (IRdye 800CW) clearance measured by multispectral optoacoustic tomography (MSOT). The results showed that in wild‐type mice, IRdye 800CW movement from kidney cortex to the medulla/pelvis region was significantly slower after CLP, compared to sham control. The sepsis‐induced impairment in renal clearance was alleviated in Zdhhc21dep/dep mice. Consistently, histological analysis (Periodic acid‐Schiff staining) revealed that CLP caused kidney structural damages, evidenced by tubular vacuolation, brush border loss, tubular cell detachment and leukocyte infiltration; these pathologies were greatly ameliorated in DHHC21 loss‐of‐function mice. Moreover, compared with wild‐type mice, Zdhhc21dep/dep mice exhibited reduced CLP‐induced increases in circulating creatinine and urea nitrogen. Mechanistically, a decreased ratio of oxygenated to deoxygenated hemoglobin was detected in kidneys of wild‐type mice following CLP, suggesting renal tissue hypoxia in response to sepsis. We then asked whether this lack of oxygenation is associated with reduced renal blood flow due to arterial constriction and whether α1AR palmitoylation is involved in this process. Indeed, we found a significant increase in α1AR palmitoylation, along with activation of the α1AR downstream effector ERK, in renal arteries of wild‐type mice following CLP. These molecular responses occurred concomitantly with a reduced renal blood flow, measured by a transonic flowmeter. In contrast, sepsis‐induced α1AR palmitoylation/activation in renal arteries was greatly attenuated in Zdhhc21dep/dep mice, consistent with a better‐preserved renal blood flow in these mice. Taken together, our findings indicate that DHHC21‐mediated α1AR palmitoylation contributes to renal blood flow reduction and kidney injury during sepsis.Support or Funding InformationThis work was supported by the National Institutes of Health Grant HL070752 (to SYY)
Akt‐PI3K signaling pathway is a crucial player in dopamine D2 receptor‐mediated emesis in least shrews
Authors: Belkacemi Louiza , Zhong Weixia , Darmani Nissar Ahmad 
Published: April 2020

Dopamine is a member of the catecholamine family involved in multiple physiological functions. Together with its five dopaminergic receptors (DRs), DA is associated with several neurological diseases including restless leg syndrome, schizophrenia, Parkinson’s disease, and depression. Unfortunately, most DR‐based agonists used to treat some of these diseases evoke nausea and vomiting as impending side‐effects. Coincidently, activation of the kinase phosphoinositide 3‐kinase (PI3K)/protein kinase B (Akt) pathway not only plays a significant role in the onset and the progression of neurodegenerative disorders but may also evoke emesis caused by stimulation of dopamine D2 receptor (DR2). Thus, the aim of this study was to decipher the role of Akt in DR2‐induced emesis using the least shrew model of vomiting (Cryptotis parva). Shrews were injected intraperitoneally (i.p.) with a fully effective emetic dose of the DR2 preferring agonist quinpirole (2 mg/kg) in the presence and the absence of either: i) a corresponding DR2 antagonist sulpiride (subcutaneous (s.c.), 8 mg/kg), or ii) incremental doses of the PI3K inhibitor LY294002 (0, 5, 10 mg/kg, i.p.). The treated shrews were observed for 30 mins for vomiting behavior following quinpirole injection. Another set of shrews were treated with 2 mg/kg quinpirole alone (N = 4 per group) and sacrificed at 5, 15, and 30 mins to determine the time‐dependent profile of Akt phosphorylation. The animals were then perfused, and brains collected for immunohistochemistry studies or brainstems harvested for Western blot analysis on protein extracts. For antagonist studies, different groups of shrews were given sulpiride (8 mg/kg, s.c) or LY294002 (10 mg/kg, i.p.) (N = 4–6 per group) for 30 mins prior to injection of quinpirole (2 mg/kg) and brainstems were collected after 15 mins for Western blot analysis. Behavioral results showed that quinpirole induced vomiting was significantly blocked by sulpiride (8 mg/kg) and LY296004 (10 mg/kg). Akt phosphorylation at Ser473 was significantly increased at 15 and 30 mins in the brainstem with quinpirole treatment alone. The increase of phospho‐Akt protein in brainstem emetic nuclei [area postrema (AP), nucleus of the solitary tract (NTS), and dorsal motor nucleus of the vagus (DMNX)] was further confirmed through immunostaining brainstem sections of quinpirole‐treated least shrews. Sulpiride on the other hand significantly inhibited quinpirole‐induced Akt and PI3K protein phosphorylation at 15 mins. Likewise, LY29004 prevented Akt activation at 15 mins. Our findings uncovered a crucial role for DR2‐mediated Akt activation in emesis and suggest targeting signals up upstream of Akt enzyme may offer new avenues for potential potent antiemetics.Support or Funding InformationThis work was supported in part by NIH‐NCI grant RO1CA207287 and the WesternU startup fund (1395) to ND.
Those Who Can’t Do, Teach&[hellip]Anatomy? The Presence of Stereotype Threat in Anatomical Sciences Educators
Authors: Cale Andrew S. , Lee Lisa M. J. 
Published: April 2020

BackgroundAnatomical sciences educators play a critical role in training future health professionals and researchers. However, in academic culture, teaching is often negatively stereotyped and less respected. As a result, educators are vulnerable to stereotype threat, a situation in which an individual underperforms due to their fear of confirming a negative stereotype associated with their group.MethodsThis IRB‐Exempt study (COMIRB #19‐1572) was designed to identify the associations of stereotype awareness and concern in anatomical sciences educators. Educators from post‐secondary and health professional institutions were invited to complete a survey consisting of demographic and 5‐point Likert scale questions regarding six domains: educator identification, institutional identification, stereotype awareness and concern, imposter tendencies, anxiety, and confidence. Spearman’s correlation was applied to survey responses from all educators as well as subgroups based on gender, ethnicity, highest degree, and academic appointment to identify statistically significant correlations.ResultsA total of 100 anatomical sciences educators completed the survey. In these individuals, stereotype awareness and concern was positively correlated with anxiety (r=0.293, p<0.003), imposter tendencies (r=0.348, p<0.001), and teaching load (r=0.275, p=0.006) as well as negatively correlated with identification with institution (r=−0.404, p<0.001) and confidence (r=−0.340, p=0.001). Ethnic minorities, non‐doctoral degree holders, and early career educators also exhibited statistically significant, but more pronounced correlations.ConclusionThis study demonstrates that awareness and concerns regarding negative teaching faculty stereotypes is linked to varying degrees with institutional disidentification, imposter tendencies, anxiety, and diminished confidence in anatomical sciences educators.
Heat stress defense in dental pulp stem cells
Authors: Xiao Nan Tori , Dakafay Harmony Matshik , Thor Der 
Published: April 2020

Many dental treatment procedures can generate excessive heat within a short period of time. The heat on the tooth surface can be transduced to the dental pulp chamber and lead to alteration of dental pulp stem cells, vascular structures and sensory neurons within the chamber. It has been reported that elevation of temperature by 5.5°C in the pulp chamber caused 15% irreversible pulpal damage. However, the molecular changes of dental pulp cells post heat stress has not been characterized. In this study, we explored the changes in human dental pulp Stem Cells from the Exfoliated Deciduous teeth (SHED) after exposure to heat stress.Lysate of SHED cells were collected after exposure to heat stress at 42°C or normal culture temperature at 37°C. Western blots were used to examine the expression of Heat Shock Proteins (HSP). Human cytokine arrays (AAH‐CYT‐5, RayBiotech) were used to evaluate the changes in the expression of 80 human cytokines in SHED cells after heat stress.Short term exposure to heat stress induced phosphorylation of HSP27. Prolonged exposure further increased expression of other heat shock proteins, which have been reported to play an important role in cell protection under stress. In addition, transient exposure to heat stress caused differential expression of cytokines in SHED cells, suppressing expression of cytokines as IL‐1a and IL‐10, while increasing expression of glial cell derived neurotrophic factor (GDNF) and insulin‐like growth factor ‐1 (IGF‐1).The results showed HSPs and multiple cytokines play important role in detecting and responding to heat stress on the SHED cells. These factors could potentially protect SHED cells from thermal damage and promote stem cell regeneration post thermal damage.Support or Funding InformationFaculty Scholarly/Artistic Activities Award DDNA12‐013 University of the Pacific.