, a bio/informatics shared resource is still "open for business" - Visit the CDS website


Other search tools

About this data

The publication data currently available has been vetted by Vanderbilt faculty, staff, administrators and trainees. The data itself is retrieved directly from NCBI's PubMed and is automatically updated on a weekly basis to ensure accuracy and completeness.

If you have any questions or comments, please contact us.

Results: 1 to 10 of 1086

Publication Record

Connections

Arachidonic Acid Kills Staphylococcus aureus through a Lipid Peroxidation Mechanism.
Beavers WN, Monteith AJ, Amarnath V, Mernaugh RL, Roberts LJ, Chazin WJ, Davies SS, Skaar EP
(2019) mBio 10:
MeSH Terms: Animals, Anti-Bacterial Agents, Arachidonic Acid, Brain, Dose-Response Relationship, Drug, Drug Resistance, Bacterial, Female, Kidney, Lipid Peroxidation, Lipids, Mice, Mice, Inbred BALB C, Microbial Sensitivity Tests, Mutation, Neutrophils, Oxidative Stress, Reactive Oxygen Species, Spleen, Staphylococcal Infections, Staphylococcus aureus, Teichoic Acids
Show Abstract · Added March 11, 2020
infects every niche of the human host. In response to microbial infection, vertebrates have an arsenal of antimicrobial compounds that inhibit bacterial growth or kill bacterial cells. One class of antimicrobial compounds consists of polyunsaturated fatty acids, which are highly abundant in eukaryotes and encountered by at the host-pathogen interface. Arachidonic acid (AA) is one of the most abundant polyunsaturated fatty acids in vertebrates and is released in large amounts during the oxidative burst. Most of the released AA is converted to bioactive signaling molecules, but, independently of its role in inflammatory signaling, AA is toxic to Here, we report that AA kills through a lipid peroxidation mechanism whereby AA is oxidized to reactive electrophiles that modify macromolecules, eliciting toxicity. This process is rescued by cotreatment with antioxidants as well as in a strain genetically inactivated for (USA300 mutant) that produces lower levels of reactive oxygen species. However, resistance to AA stress in the USA300 mutant comes at a cost, making the mutant more susceptible to β-lactam antibiotics and attenuated for pathogenesis in a murine infection model compared to the parental methicillin-resistant (MRSA) strain, indicating that resistance to AA toxicity increases susceptibility to other stressors encountered during infection. This report defines the mechanism by which AA is toxic to and identifies lipid peroxidation as a pathway that can be modulated for the development of future therapeutics to treat infections. Despite the ability of the human immune system to generate a plethora of molecules to control infections, is among the pathogens with the greatest impact on human health. One class of host molecules toxic to consists of polyunsaturated fatty acids. Here, we investigated the antibacterial properties of arachidonic acid, one of the most abundant polyunsaturated fatty acids in humans, and discovered that the mechanism of toxicity against proceeds through lipid peroxidation. A better understanding of the molecular mechanisms by which the immune system kills , and by which avoids host killing, will enable the optimal design of therapeutics that complement the ability of the vertebrate immune response to eliminate infections.
Copyright © 2019 Beavers et al.
0 Communities
1 Members
0 Resources
21 MeSH Terms
Individualised axitinib regimen for patients with metastatic renal cell carcinoma after treatment with checkpoint inhibitors: a multicentre, single-arm, phase 2 study.
Ornstein MC, Pal SK, Wood LS, Tomer JM, Hobbs BP, Jia XS, Allman KD, Martin A, Olencki T, Davis NB, Gilligan TD, Mortazavi A, Rathmell WK, Garcia JA, Rini BI
(2019) Lancet Oncol 20: 1386-1394
MeSH Terms: Aged, Algorithms, Antineoplastic Agents, Antineoplastic Agents, Immunological, Axitinib, Carcinoma, Renal Cell, Dehydration, Diarrhea, Fatigue, Female, Humans, Hypertension, Ipilimumab, Kidney Neoplasms, Male, Middle Aged, Nivolumab, Progression-Free Survival, Response Evaluation Criteria in Solid Tumors, Retreatment
Show Abstract · Added October 30, 2019
BACKGROUND - Checkpoint inhibitor therapy is a standard of care for patients with metastatic renal cell carcinoma. Treatment options after checkpoint inhibitor therapy include vascular endothelial growth factor receptor (VEGF-R) tyrosine kinase inhibitors, although no prospective data regarding their use in this setting exist. Axitinib is a VEGF-R inhibitor with clinical data supporting increased activity with dose titration. We aimed to investigate the activity of dose titrated axitinib in patients with metastatic renal cell carcinoma who were previously treated with checkpoint inhibitor.
METHODS - We did a multicentre, phase 2 trial of axitinib given on an individualised dosing algorithm. Patients at least 18 years of age with histologically or cytologically confirmed locally recurrent or metastatic renal cell carcinoma with clear cell histology, a Karnofsky Performance Status of 70% or more, and measurable disease who received checkpoint inhibitor therapy as the most recent treatment were eligible. There was no limit on number of previous therapies received. Patients received oral axitinib at a starting dose of 5 mg twice daily with dose titration every 14 days in 1 mg increments (ie, 5 mg twice daily to 6 mg twice daily, up to 10 mg twice daily maximum dose) if there was no axitinib-related grade 2 or higher mucositis, diarrhoea, hand-foot syndrome, or fatigue. If one or more of these grade 2 adverse events occurred, axitinib was withheld for 3 days before the same dose was resumed. Dose reductions were made if recurrent grade 2 adverse events despite treatment breaks or grade 3-4 adverse events occurred. The primary outcome was progression-free survival. Analyses were done per protocol in all patients who received at least one dose of axitinib. Recruitment has been completed and the trial is ongoing. This trial is registered with ClincalTrials.gov, number NCT02579811.
FINDINGS - Between Jan 5, 2016 and Feb 21, 2018, 40 patients were enrolled and received at least one dose of study treatment. With a median follow-up of 8·7 months (IQR 3·7-14·2), the median progression-free survival was 8·8 months (95% CI 5·7-16·6). Fatigue (83%) and hypertension (75%) were the most common all-grade adverse events. The most common grade 3 adverse event was hypertension (24 patients [60%]). There was one (3%) grade 4 adverse event (elevated lipase) and no treatment-related deaths occurred. Serious adverse events that were likely related to therapy occurred in eight (20%) patients; the most common were dehydration (n=4) and diarrhoea (n=2).
INTERPRETATION - Individualised axitinib dosing in patients with metastatic renal cell inoma previously treated with checkpoint inhibitors did not meet the prespecified threshold for progression free survival, but these data show that this individualised titration scheme is feasible and has robust clinical activity. These prospective results warrant consideration of axitinib in this setting.
FUNDING - Pfizer.
Copyright © 2019 Elsevier Ltd. All rights reserved.
0 Communities
1 Members
0 Resources
20 MeSH Terms
Brucella abortus Infection of Placental Trophoblasts Triggers Endoplasmic Reticulum Stress-Mediated Cell Death and Fetal Loss via Type IV Secretion System-Dependent Activation of CHOP.
Byndloss MX, Tsai AY, Walker GT, Miller CN, Young BM, English BC, Seyffert N, Kerrinnes T, de Jong MF, Atluri VL, Winter MG, Celli J, Tsolis RM
(2019) mBio 10:
MeSH Terms: Animals, Brucella abortus, Cell Death, Endoplasmic Reticulum Stress, Female, Mice, Mice, Inbred C57BL, Nod1 Signaling Adaptor Protein, Nod2 Signaling Adaptor Protein, Placenta, Pregnancy, Transcription Factor CHOP, Trophoblasts, Type IV Secretion Systems, Unfolded Protein Response
Show Abstract · Added March 30, 2020
Subversion of endoplasmic reticulum (ER) function is a feature shared by multiple intracellular bacteria and viruses, and in many cases this disruption of cellular function activates pathways of the unfolded protein response (UPR). In the case of infection with , the etiologic agent of brucellosis, the unfolded protein response in the infected placenta contributes to placentitis and abortion, leading to pathogen transmission. Here we show that infection of pregnant mice led to death of infected placental trophoblasts in a manner that depended on the VirB type IV secretion system (T4SS) and its effector VceC. The trophoblast death program required the ER stress-induced transcription factor CHOP. While NOD1/NOD2 expression in macrophages contributed to ER stress-induced inflammation, these receptors did not play a role in trophoblast death. Both placentitis and abortion were independent of apoptosis-associated Speck-like protein containing a caspase activation and recruitment domain (ASC). These studies show that uses its T4SS to induce cell-type-specific responses to ER stress in trophoblasts that trigger placental inflammation and abortion. Our results suggest further that in the T4SS and its effectors are under selection as bacterial transmission factors. infects the placenta of pregnant cows, where it replicates to high levels and triggers abortion of the calf. The aborted material is highly infectious and transmits infection to both cows and humans, but very little is known about how causes abortion. By studying this infection in pregnant mice, we discovered that kills trophoblasts, which are important cells for maintaining pregnancy. This killing required an injected bacterial protein (VceC) that triggered an endoplasmic reticulum (ER) stress response in the trophoblast. By inhibiting ER stress or infecting mice that lack CHOP, a protein induced by ER stress, we could prevent death of trophoblasts, reduce inflammation, and increase the viability of the pups. Our results suggest that injects VceC into placental trophoblasts to promote its transmission by abortion.
Copyright © 2019 Byndloss et al.
0 Communities
1 Members
0 Resources
15 MeSH Terms
IRE1α-XBP1 signaling in leukocytes controls prostaglandin biosynthesis and pain.
Chopra S, Giovanelli P, Alvarado-Vazquez PA, Alonso S, Song M, Sandoval TA, Chae CS, Tan C, Fonseca MM, Gutierrez S, Jimenez L, Subbaramaiah K, Iwawaki T, Kingsley PJ, Marnett LJ, Kossenkov AV, Crespo MS, Dannenberg AJ, Glimcher LH, Romero-Sandoval EA, Cubillos-Ruiz JR
(2019) Science 365:
MeSH Terms: Animals, Cells, Cultured, Cyclooxygenase 2, Dinoprostone, Endoribonucleases, Humans, Leukocytes, Mice, Mice, Inbred C57BL, Myeloid Cells, Pain, Postoperative, Promoter Regions, Genetic, Prostaglandin-E Synthases, Protein-Serine-Threonine Kinases, Signal Transduction, Unfolded Protein Response, Visceral Pain, X-Box Binding Protein 1
Show Abstract · Added March 12, 2020
Inositol-requiring enzyme 1[α] (IRE1[α])-X-box binding protein spliced (XBP1) signaling maintains endoplasmic reticulum (ER) homeostasis while controlling immunometabolic processes. Yet, the physiological consequences of IRE1α-XBP1 activation in leukocytes remain unexplored. We found that induction of prostaglandin-endoperoxide synthase 2 (/Cox-2) and prostaglandin E synthase (/mPGES-1) was compromised in IRE1α-deficient myeloid cells undergoing ER stress or stimulated through pattern recognition receptors. Inducible biosynthesis of prostaglandins, including the pro-algesic mediator prostaglandin E2 (PGE), was decreased in myeloid cells that lack IRE1α or XBP1 but not other ER stress sensors. Functional XBP1 transactivated the human and genes to enable optimal PGE production. Mice that lack IRE1α-XBP1 in leukocytes, or that were treated with IRE1α inhibitors, demonstrated reduced pain behaviors in PGE-dependent models of pain. Thus, IRE1α-XBP1 is a mediator of prostaglandin biosynthesis and a potential target to control pain.
Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
0 Communities
1 Members
0 Resources
18 MeSH Terms
Ceapins block the unfolded protein response sensor ATF6α by inducing a neomorphic inter-organelle tether.
Torres SE, Gallagher CM, Plate L, Gupta M, Liem CR, Guo X, Tian R, Stroud RM, Kampmann M, Weissman JS, Walter P
(2019) Elife 8:
MeSH Terms: ATP-Binding Cassette Transporters, Activating Transcription Factor 6, CRISPR-Cas Systems, Endoplasmic Reticulum, HEK293 Cells, Hep G2 Cells, Humans, Organelles, Peroxisomes, Phenotype, Protein Binding, Small Molecule Libraries, Unfolded Protein Response
Show Abstract · Added March 3, 2020
The unfolded protein response (UPR) detects and restores deficits in the endoplasmic reticulum (ER) protein folding capacity. Ceapins specifically inhibit the UPR sensor ATF6α, an ER-tethered transcription factor, by retaining it at the ER through an unknown mechanism. Our genome-wide CRISPR interference (CRISPRi) screen reveals that Ceapins function is completely dependent on the ABCD3 peroxisomal transporter. Proteomics studies establish that ABCD3 physically associates with ER-resident ATF6α in cells and in vitro in a Ceapin-dependent manner. Ceapins induce the neomorphic association of ER and peroxisomes by directly tethering the cytosolic domain of ATF6α to ABCD3's transmembrane regions without inhibiting or depending on ABCD3 transporter activity. Thus, our studies reveal that Ceapins function by chemical-induced misdirection which explains their remarkable specificity and opens up new mechanistic routes for drug development and synthetic biology.
© 2019, Torres et al.
0 Communities
1 Members
0 Resources
MeSH Terms
A Novel Class of Common Docking Domain Inhibitors That Prevent ERK2 Activation and Substrate Phosphorylation.
Sammons RM, Perry NA, Li Y, Cho EJ, Piserchio A, Zamora-Olivares DP, Ghose R, Kaoud TS, Debevec G, Bartholomeusz C, Gurevich VV, Iverson TM, Giulianotti M, Houghten RA, Dalby KN
(2019) ACS Chem Biol 14: 1183-1194
MeSH Terms: Binding Sites, Crystallography, X-Ray, Dose-Response Relationship, Drug, Enzyme Activation, Guanidine, Humans, Mitogen-Activated Protein Kinase 1, Nuclear Magnetic Resonance, Biomolecular, Phosphorylation, Protein Kinase Inhibitors, Substrate Specificity
Show Abstract · Added March 18, 2020
Extracellular signal-regulated kinases (ERK1/2) are mitogen-activated protein kinases (MAPKs) that play a pro-tumorigenic role in numerous cancers. ERK1/2 possess two protein-docking sites that are distinct from the active site: the D-recruitment site (DRS) and the F-recruitment site. These docking sites facilitate substrate recognition, intracellular localization, signaling specificity, and protein complex assembly. Targeting these sites on ERK in a therapeutic context may overcome many problems associated with traditional ATP-competitive inhibitors. Here, we identified a new class of inhibitors that target the ERK DRS by screening a synthetic combinatorial library of more than 30 million compounds. The screen detects the competitive displacement of a fluorescent peptide from the DRS of ERK2. The top molecular scaffold from the screen was optimized for structure-activity relationship by positional scanning of different functional groups. This resulted in 10 compounds with similar binding affinities and a shared core structure consisting of a tertiary amine hub with three functionalized cyclic guanidino branches. Compound 2507-1 inhibited ERK2 from phosphorylating a DRS-targeting substrate and prevented the phosphorylation of ERK2 by a constitutively active MEK1 (MAPK/ERK kinase 1) mutant. Interaction between an analogue, 2507-8, and the ERK2 DRS was confirmed by nuclear magnetic resonance and X-ray crystallography. 2507-8 forms critical interactions at the common docking domain residue Asp319 via an arginine-like moiety that is shared by all 10 hits, suggesting a common binding mode. The structural and biochemical insights reported here provide the basis for developing new ERK inhibitors that are not ATP-competitive but instead function by disrupting critical protein-protein interactions.
0 Communities
1 Members
0 Resources
MeSH Terms
Late immune consequences of combat trauma: a review of trauma-related immune dysfunction and potential therapies.
Thompson KB, Krispinsky LT, Stark RJ
(2019) Mil Med Res 6: 11
MeSH Terms: Adaptive Immunity, Humans, Immunity, Innate, Immunomodulation, Military Personnel, Multiple Organ Failure, Systemic Inflammatory Response Syndrome, Wound Healing, Wounds and Injuries
Show Abstract · Added April 25, 2019
With improvements in personnel and vehicular body armor, robust casualty evacuation capabilities, and damage control resuscitation strategies, more combat casualties are surviving to reach higher levels of care throughout the casualty evacuation system. As such, medical centers are becoming more accustomed to managing the deleterious late consequences of combat trauma related to the dysregulation of the immune system. In this review, we aim to highlight these late consequences and identify areas for future research and therapeutic strategies. Trauma leads to the dysregulation of both the innate and adaptive immune responses, which places the injured at risk for several late consequences, including delayed wound healing, late onset sepsis and infection, multi-organ dysfunction syndrome, and acute respiratory distress syndrome, which are significant for their association with the increased morbidity and mortality of wounded personnel. The mechanisms by which these consequences develop are complex but include an imbalance of the immune system leading to robust inflammatory responses, triggered by the presence of damage-associated molecules and other immune-modifying agents following trauma. Treatment strategies to improve outcomes have been difficult to develop as the immunophenotype of injured personnel following trauma is variable, fluid and difficult to determine. As more information regarding the triggers that lead to immune dysfunction following trauma is elucidated, it may be possible to identify the immunophenotype of injured personnel and provide targeted treatments to reduce the late consequences of trauma, which are known to lead to significant morbidity and mortality.
0 Communities
1 Members
0 Resources
9 MeSH Terms
Rabbit Model of Intra-Arterial Chemotherapy Toxicity Demonstrates Retinopathy and Vasculopathy Related to Drug and Dose, Not Procedure or Approach.
Daniels AB, Froehler MT, Nunnally AH, Pierce JM, Bozic I, Stone CA, Santapuram PR, Tao YK, Boyd KL, Himmel LE, Chen SC, Du L, Friedman DL, Richmond A
(2019) Invest Ophthalmol Vis Sci 60: 954-964
MeSH Terms: Animals, Antineoplastic Agents, Antineoplastic Agents, Alkylating, Carboplatin, Dose-Response Relationship, Drug, Electroretinography, Female, Fluorescein Angiography, Humans, Infant, Infusions, Intra-Arterial, Male, Melphalan, Models, Animal, Ophthalmic Artery, Rabbits, Retina, Retinal Diseases, Retinal Neoplasms, Retinal Vessels, Retinoblastoma, Retrospective Studies, Tomography, Optical Coherence
Show Abstract · Added July 29, 2019
Purpose - To use our intra-arterial chemotherapy (IAC) rabbit model to assess the impact of IAC procedure, drug, dose, and choice of technique on ocular structure and function, to study the nature and etiology of IAC toxicity, and to compare to observations in patients.
Methods - Rabbits received IAC melphalan (0.4-0.8 mg/kg), carboplatin (25-50 mg), or saline, either by direct ophthalmic artery cannulation, or with a technique emulating nonocclusion. Ocular structure/function were assessed with examination, electroretinography (ERG), fundus photography, fluorescein angiography, optical coherence tomography (OCT), and OCT angiography, prior to and 5 to 6 weeks after IAC. Blood counts were obtained weekly. We reviewed our last 50 IAC treatments in patients for evidence of ocular or systemic complications.
Results - No toxicity was seen in the saline control group. With standard (0.4 mg/kg) melphalan, no vascular/microvascular abnormalities were seen with either technique. However, severe microvascular pruning and arteriolar occlusions were seen occasionally at 0.8 mg/kg doses. ERG reductions were dose-dependent. Histology showed melphalan dose-dependent degeneration in all retinal layers, restricted geographically to areas of greatest vascular density. Carboplatin caused massive edema of ocular/periocular structures. IAC patients experienced occasional periocular swelling/rash, and only rarely experienced retinopathy or vascular events/hemorrhage in eyes treated multiple times with triple (melphalan/carboplatin/topotecan) therapy. Transient neutropenia occurred after 46% of IAC procedures, generally after triple therapy.
Conclusions - IAC toxicity appears to be related to the specific drug being used and is dose-dependent, rather than related to the IAC procedure itself or the specific technique selected. These rabbit findings are corroborated by our clinical findings in patients.
0 Communities
2 Members
0 Resources
23 MeSH Terms
Deconvoluting Stress-Responsive Proteostasis Signaling Pathways for Pharmacologic Activation Using Targeted RNA Sequencing.
Grandjean JMD, Plate L, Morimoto RI, Bollong MJ, Powers ET, Wiseman RL
(2019) ACS Chem Biol 14: 784-795
MeSH Terms: Animals, HEK293 Cells, Heat Shock Transcription Factors, Humans, Mice, NF-E2 Transcription Factor, Oxidative Stress, Proteostasis, Sequence Analysis, RNA, Signal Transduction, Unfolded Protein Response
Show Abstract · Added March 3, 2020
Cellular proteostasis is maintained by stress-responsive signaling pathways such as the heat shock response (HSR), the oxidative stress response (OSR), and the unfolded protein response (UPR). Activation of these pathways results in the transcriptional upregulation of select subsets of stress-responsive genes that restore proteostasis and adapt cellular physiology to promote recovery following various types of acute insult. The capacity for these pathways to regulate cellular proteostasis makes them attractive therapeutic targets for correcting proteostasis defects associated with diverse diseases. High-throughput screening (HTS) using cell-based reporter assays is highly effective for identifying putative activators of stress-responsive signaling pathways. However, the development of these compounds is hampered by the lack of medium-throughput assays to define compound potency and selectivity for a given pathway. Here, we describe a targeted RNA sequencing (RNAseq) assay that allows cost-effective, medium-throughput screening of stress-responsive signaling pathway activation. We demonstrate that this assay allows deconvolution of stress-responsive signaling activated by chemical genetic or pharmacologic agents. Furthermore, we use this assay to define the selectivity of putative OSR and HSR activating compounds previously identified by HTS. Our results demonstrate the potential for integrating this adaptable targeted RNAseq assay into screening programs focused on developing pharmacologic activators of stress-responsive signaling pathways.
0 Communities
1 Members
0 Resources
MeSH Terms
Pharmacologic ATF6 activation confers global protection in widespread disease models by reprograming cellular proteostasis.
Blackwood EA, Azizi K, Thuerauf DJ, Paxman RJ, Plate L, Kelly JW, Wiseman RL, Glembotski CC
(2019) Nat Commun 10: 187
MeSH Terms: Activating Transcription Factor 6, Animals, Animals, Newborn, Cells, Cultured, Cerebral Infarction, Disease Models, Animal, Endoplasmic Reticulum, Female, Heart Ventricles, Humans, Kidney, Kidney Diseases, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Myocardial Infarction, Myocytes, Cardiac, Primary Cell Culture, Protective Agents, Proteostasis, Rats, Reperfusion Injury, Treatment Outcome, Unfolded Protein Response
Show Abstract · Added March 3, 2020
Pharmacologic activation of stress-responsive signaling pathways provides a promising approach for ameliorating imbalances in proteostasis associated with diverse diseases. However, this approach has not been employed in vivo. Here we show, using a mouse model of myocardial ischemia/reperfusion, that selective pharmacologic activation of the ATF6 arm of the unfolded protein response (UPR) during reperfusion, a typical clinical intervention point after myocardial infarction, transcriptionally reprograms proteostasis, ameliorates damage and preserves heart function. These effects were lost upon cardiac myocyte-specific Atf6 deletion in the heart, demonstrating the critical role played by ATF6 in mediating pharmacologically activated proteostasis-based protection of the heart. Pharmacological activation of ATF6 is also protective in renal and cerebral ischemia/reperfusion models, demonstrating its widespread utility. Thus, pharmacologic activation of ATF6 represents a proteostasis-based therapeutic strategy for ameliorating ischemia/reperfusion damage, underscoring its unique translational potential for treating a wide range of pathologies caused by imbalanced proteostasis.
0 Communities
1 Members
0 Resources
MeSH Terms