bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discerning the Mechanism of HLA Expression by Epigenetic Modulators in Breast Cancer Cell Lines
Authors: Terrigino Nicholas Taylor , Powers Rachel Elizabeth , O'Donnell Robert Watts 
Published: June 2021

Our previous studies showed that the combination of a histone deacetylase inhibitor (Entinostat) and a DNA methyltransferase inhibitor (5‐Azacytidine) work in an additive fashion to upregulate surface Human Leukocyte Antigens (HLA) which are typically downregulated in cancer cells. The current study centers on Vorinostat, a histone deacetylase inhibitor, and 5‐Azacytidine, a DNA methyltransferase inhibitor, which allow us to study the regulation of HLA Class 1 expression in the breast cancer cell lines, MDA‐MB‐231 and MCF‐7. Using RT‐qPCR, we are testing for the expression of mRNAs for HLAs and the Antigen Processing Machinery (APM) responsible for placing peptides into these class I proteins and transporting them from the ER to the cell surface. The mRNA levels of APM genes TAP1, TAP2, and LMP2 showed a marked increase upon treatment with the drug combination when compared to the control. The LMP7 mRNA levels showed only a small increase upon treatment with the drug combination when compared to the control. Through flow cytometry, we have demonstrated that, in MCF‐7 cells, the combination of Vorinostat and 5‐Azacytidine caused the highest increase in HLA and Beta‐2 microglobulin expression when compared to each treatment alone. In the case of the MDA‐MB‐231 cells, the drug combination demonstrated the highest increase in Beta‐2 microglobulin expression, but not the highest increase in HLA expression when compared to each treatment alone. Future experiments are planned to determine the amount of HLA protein intracellularly, further assess the APM mRNA levels, and histone positioning at these genes. Discerning the mechanism of the HLA upregulation may help to design treatments which optimize HLA expression, and thus increase the efficacy of new immunotherapies that use checkpoint inhibitors like anti‐CTLA‐4 and anti‐PD‐1.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of Plasmodium falciparum on Placental Expression of Inflammatory and Coagulation Factors
Authors: Dalapati Trisha 
Published: June 2021

Plasmodium falciparum infection during pregnancy, which can develop into placental malaria (PM), is estimated to cause over 200,000 infant deaths annually. PM is characterized by sequestration of parasite infected red blood cells (iRBCs) and deposition of hemozoin (HZ) in the maternal blood (intervillous) space of the placenta. HZ is an insoluble, iron‐containing by‐product of the parasite's digestion of hemoglobin. Additionally, accumulation of maternal immune cells and excessive deposition of fibrin are seen in the intervillous space. The role of the syncytiotrophoblast (ST), the outermost cell layer of the placenta, during PM pathogenesis remains unclear. It is hypothesized that the ST responds to iRBCs, HZ, and inflammatory cytokines like tumor necrosis factor (TNF) produced by maternal immune cells to attenuate infection. However, it is ultimately harmed by its own response. Mechanistically, it is predicted that TNF leads to activation of tissue factor (TF), the initiator of the extrinsic coagulation pathway, which ultimately results in fibrin deposition. In addition to TNF, HZ released from iRBCs may also upregulate TF. Downstream coagulation factors activate protease activated receptors (PARs), which are G‐protein coupled receptors highly expressed on the ST. Activated PARs increase expression of TNF, propagating what is known as “the inflammation‐coagulation cycle”. The cycle's propagation adversely affects nutrient and gas exchange between the maternal blood and the ST, resulting in growth restriction, low birth weight, and occasionally death of the fetus. Using a human choriocarcinoma cell line, BeWo, and isolated human trophoblast cells, in vivo host (ST)‐parasite interactions are simulated. BeWos and human trophoblasts are left unstimulated or stimulated over a physiologically relevant time‐course with (1) lipopolysaccharide (LPS; positive control), (2) natural HZ, (3) TNF, or (4) natural HZ/TNF. RNA isolation is followed by cDNA generation and qPCR for TF, PAR‐1, and PAR‐2. Results indicate that BeWos respond to LPS and HZ with a modest upregulation of TF and PAR‐1 between 2 to 4 hours. Response to TNF occurs at 2 hours with a modest upregulation of TF. Gene expression of PAR‐2 was not found to be significant over the time‐course. qPCR results with cDNA generated from time‐course experiments using human trophoblast cells are forthcoming. Identifying the extent to which the ST is involved in PM pathogenesis will advanced the understanding of how this syndrome impacts fetal development and outcome.Support or Funding InformationThis work is supported by National Institutes of Health grant 1R21AI111242 to Dr. Julie M. Moore.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Assisted Insertion of Pseudomonas aeruginosa Type Three Secretion Translocator PopD in Membranes by Translocator PopB
Authors: Tang Yuzhou , Heuck Alejandro P. 
Published: June 2021

Type III secretion (T3S) system is deployed by a wide range of pathogens to manipulate host cell response and establish infection. The T3S system is a syringe‐like apparatus that spans across the double membrane of bacteria, protruding 40nm–80nm into the extracellular space and connecting with target cell membrane. In Pseudomonas aeruginosa, the proteins PopB and PopD are secreted and found associated with the target eukaryotic cell membrane. These two proteins are believed to form a transmembrane complex or translocon to allow effector protein translocation. We have recently determined that PopD alone can spontaneously oligomerize and form mostly homo‐complexes of six subunits in the membrane. Interestingly, PopB and PopD together form membrane‐inserted hetero‐complexes that contain eight subunits of PopB and eight of PopD. However, the assembly mechanism to form these complexes remains unknown.Here, we investigated how PopD interacts with membranes when assembled into the PopB/D hetero‐complex using a combination of biochemical and biophysical techniques that report on the environment and location of individual amino acid. Our data suggested that the presence of PopB triggers conformational change in membrane associated PopD in lipid bilayers. Using a cell based phosphorylation assay, we also found a similar conformational change of PopD in infected HeLa cell membranes. Together, our results showed that PopB assists the membrane insertion of PopD.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of Chronic, Intermittent Sucrose Consumption on the Discriminative Stimulus Effects of Dopamine or Opioid Antagonists
Authors: Marek Morgan A. , Rothbauer Dylan R. , Schulz Emily N. , Barton Allison C. , Tryhus Aaron M. , Hardorn‐Papke Damin J. , Brandt Lucas J. , Jewett David C. 
Published: June 2021

Chronic, intermittent sucrose access has been shown to induce neurochemical changes in the brain, including increasing the levels of dopamine and D3‐receptor mRNA, decreasing the levels of D2‐receptor mRNA, and increasing μ‐opioid receptor binding. We wondered if chronic, intermittent sucrose consumption would alter the ability of rats to discriminate drugs that affect endorphin and dopamine functioning. We successfully trained rats with chronic, intermittent sucrose access to discriminate various naltrexone training doses (ranging from 0.32 – 3.2 mg/kg) from saline. In the present series of studies, we sought to determine if chronic, intermittent sucrose consumption alters the ability of haloperidol to serve as a discriminative stimulus. Sprague‐Dawley rats were trained to discriminate between haloperidol [0.018–0.56 mg/kg, 30 min pretreatment (PT)] and vehicle in a two‐lever, operant choice procedure. Most subjects reached the discrimination criteria (80% or greater condition‐appropriate responding for 8 of 10 consecutive sessions). Among subjects that acquired the discrimination, there were no significant differences in acquisition between subjects with chronic, intermittent sucrose access and subjects with 24‐hr water access. Haloperidol (0.032 – 0.056 mg/kg) produced significant rate suppression. Increasing the PT to 60 minutes increased rates of lever pressing and reinforcers earned, but did not alter haloperidol generalization functions. Taken together, chronic sucrose consumption enhanced naltrexone's ability to function as a discriminative stimulus, but did not affect the discriminative stimulus effects of haloperidol.Support or Funding InformationUniversity of Wisconsin‐Eau Claire Office of Research and Sponsored ProgramsThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Characterization of a Novel Series of D4 Dopamine Receptor Ligands Reveals Structure‐Activity Relationships for Selective Partial Agonists
Authors: Day Marilyn M. , Free R. Benjamin , Stang Christopher R.T. , Boateng Comfort A. , Keck Thomas M. , Sibley David R. 
Published: June 2021

D4 dopamine receptors (D4R) are G protein‐coupled receptors that play important roles in cognition, attention, and decision making. D4R ligands have been shown to alter cognition and behavior in animal models of drug addiction and variations in the DRD4 gene have been associated with novelty‐seeking and risk behavior, as well as ADHD. A better understanding of D4R‐mediated signaling is essential to understanding and treating D4R‐associated disorders, including substance abuse disorders. Despite its clinical implications, there are currently few compounds that selectively modulate the D4R receptor. Such compounds are important to study D4R function and identify favorable pharmacology for disease treatment. We created a small next‐generation compound library using computational modelling to design D4R ligands based on the parental scaffold of the prototypical D4R partial agonist A‐412997. This library was analyzed for D2R, D3R, and D4R activity using both agonist and antagonist radioligand competition binding assays and functional signaling readouts (β‐arrestin recruitment and cAMP inhibition). We found that substitutions on the piperidine and pyridine moieties, as well as modifications in linker length, led to several novel lead compounds with improved selectivity and potency, and varying degrees of agonist efficacy. Compounds were identified that displayed high binding affinity (<100 nM) for the D4R coupled with a >1000‐fold selectivity vs. the D3R and D2R. Importantly, these ligands displayed a range of agonist efficacies from highly efficacious partial agonists to full antagonists of the D4R. Interestingly, some compounds with similar binding affinities showed divergent functional efficacies, allowing for the generation of a preliminary structure‐activity relationship underlying functional efficacy. Further optimization may allow for directed tuning of functional efficacy that, when coupled to in vivo behavioral studies, may provide insight into the importance of relative efficacy levels as a means to treat D4R‐related disorders.Support or Funding InformationNINDS IRPThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Th2‐driven Innate Immune Responses in Carbon Nanotube‐induced Lung Fibrosis
Authors: Ma Qiang , Dong Jie 
Published: June 2021

Aberrant tissue responses to persistent deposition of foreign bodies frequently result in organ fibrosis through orchestrated, but poorly understood processes. Carbon nanotubes are new nano materials that have found a broad range of applications in industrial and commercial products. Animal studies indicate that certaincarbon nanotubes behave as insoluble fibers that deposit in the lungs upon inhalation and stimulate a rapid onset pulmonary fibrotic response, characterized by inflammation, interstitial fibrosis, and granuloma formation. We have used multi‐walled carbon nanotubes (MWCNTs)‐induced mouse lung fibrosisas a model to analyze the molecular underpinnings of lung fibrosis induced by foreign bodies. Genome‐wide microarray analyses of the lungs exposed to MWCNTs revealed a range of differentially expressed genes involved in pathways of immune and inflammatory regulation, response to stress and extracellular stimuli, and cell migration and adhesion. In particular, the T helper 2(Th2)‐driven innate immune responses were significantly enriched. MWCNTs significantly induced the expression of Th2 cytokines, typified by interleukin(IL)‐4 and IL‐13, and a panel of Th2 signature downstream genes, such as Il4i1, Chia, and Ccl11/Eotaxin. Induction involved the activation of STAT6 via the phosphorylation of STAT6 and the up‐regulation of GATA‐3 that directly controls the transcription of Th2 target genes. These findings demonstrate the activation of Th2‐driven innate immune responses during the development of lung fibrosis induced by carbon nanotubes, providing a molecular link between Th2functions and the tissue response to foreign body deposition in mammalian lungs.Support or Funding InformationSupported by a fund to QM from National Institute for Occupational Safety and Health, Health Effects Laboratory Division and Nanotechnology Research Center.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Utilizing SULT4A1 Mutant Mouse Models to Characterize SULT4A1
Authors: Garcia Patrick L. , Hossain Mohammed I. , Andrabi Shaida A. , Falany Charles N. 
Published: June 2021

Identified by our lab in 2000, sulfotransferase 4A1 (SULT4A1) belongs to the cytosolic sulfotransferase (SULT) gene superfamily of phase II conjugation enzymes based on key sequence and structural similarities. Broadly, SULTs catalyze the transfer of a sulfonate moiety (SO3−) to a diverse set of endogenous and exogenous substrates in tandem with the obligate cofactor 3′‐phosphoadenosine‐5′‐phosphosulfate (PAPS). Expression studies have shown SULT4A1 to be localized to neuronal tissues, and SULT4A1 orthologs have been found in all vertebrate species examined. Remarkably, human SULT4A1 shares a high degree of sequence homology with other vertebrate SULT4A1 orthologs, more than any other human SULT. Despite the conserved nature of SULT4A1 among vertebrates, all attempts to demonstrate sulfotransferase activity have failed and the neuronal function of this orphan enzyme remains unclear. To elucidate an understanding of SULT4A1, CRISPR‐Cas9 gene editing technology was performed to disrupt SULT4A1 function in a C57BL/6J mouse background and two mutations of interest were pursued. A 28 bp deletion (Δ28) in exon 1 resulted in a frameshift mutation and a premature stop codon at amino acid (AA) 62. A second mutation of interest was a 12 bp (Δ12) in‐frame deletion in exon 3 of four AA immediately adjacent to the active site histidine. Dynamic modeling studies of the Δ12 mutation suggested a structural disruption to the substrate binding pocket. Interestingly, homozygous mutant pups of both lines displayed a severe and progressive neurological pathology beginning 8–10 days post‐natal, until death at day 21–25. Neurological symptoms included persistent tremor, ataxia, absence seizures, and decreased weight gain. Homozygous mutant mice of both strains were confirmed to lack detectable SULT4A1, while heterozygous mice of both strains showed a modest decrease compared to wild‐type (WT) mice. Since little is known about SULT4A1 function, subcellular fractionation was performed to determine if SULT4A1 localizes to other cellular compartments. Indeed, SULT4A1 was detected in mitochondrial, cytosolic, and microsomal fractions, a previously unreported finding. Due to the early onset of neurological symptoms, SULT4A1 expression was assessed in primary cortical neurons (PCNs) harvested from gestational day 15 mice. PCNs were cultured in vitro to day 12 and robust expression of SULT4A1 was observed in these cells by immunostaining. In summary, SULT4A1 is a critical protein for neurofunction and normal development, as mice lacking functional SULT4A1 displayed a progressively severe and lethal neurological pathology. These mutant mouse models will be instrumental into characterizing the function of SULT4A1.Support or Funding InformationThis work was supported by GM113980 to CNF and NS08695301 to SAA.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Ocular Retention and Bioavailability Studies of Bromfenac Mucoadhesive Nanoparticles by Sustained Ophthalmic Delivery
Authors: Bhavani B. , Swathi P. Kumar , Kilari Eswar Kumar 
Published: June 2021

The present study was designed to formulate the sustained ocular delivery of bromfenac loaded mucoadhesive chitosan nanoparticles (NPs). The NPS were prepared by different ratios of chitosan and sodium alginate by ionic gelation method. The prepared nanoparticles were characterized by its particle size, zeta potential, entrapment efficiency, in vitro release and ocular irritation test. The NPs are employed for transcorneal permeation and in vivo evaluation was carried out in rat eye for ocular toxicity studies. The pharmacokinetic data of selected NPs were compared with marketed bromfenac formulation (Megabrom). The selected NPs were characterized by their mean particle size 202±2.02 nm, encapsulation efficiency 73.4±1.25 % and zetapotential +32.3±0.12 mV. In vitro release exhibited biphasic drug release profile with initial burst followed by slow drug release. The NPs exhibited significant mucin adhesion. The Draize's test showed that, there was no irritation upon topical instillation of prepared NPs. The AUC (0‐α) of NPs was increased up to 4.02 fold and clearance was decreased up to 5.5 fold as compared to marketed ophthalmic formulation and were found to be safe in histopathological studies. It is concluded that he formulated bromfenac NPs showed prolong ocular residence and reducing dosing frequency.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Inhibitive Effect of Salidroside on Apoptosis of EA.hy926 Cells Induced by H2O2 under Simulated Microgravity
Authors: Yuan Min , Jia Mingwen , Wang Jingyu , Yuan Ming 
Published: June 2021

Microgravity or simulated microgravity(SM) can induce cardiovascular dysfunction in which vascular endothelial cells play an important role. Studies showed that oxidative stress was common in vascular tissues under simulated microgravity and was also increased in vascular endothelial cells during spaceflight. The purpose of this experiment is to study whether vascular endothelial cells have different biological response to oxidative stress under simulated microgravity with new generation transcriptome sequencing technology and discuss the cell protection effect of salidroside. EA.hy926 cells, a fusion of HUVECs and the lung carcinoma cell line A549, were randomly divided into control group(Con72) and clinostat group(Z72), and after clinostating for 72 hours, the two groups were randomly given the following treatment at the same time: stimulated by H2O2, stimulation by H2O2 and salidroside intervention. Apoptosis was measured by flow cytometry and transcriptome sequencing was performed by new generation sequencing technology, RT‐qPCR was used to verify the differentially expressed genes and detect the effect of salidroside on the expression of these genes. The results showed that there were obvious apoptosis in EA.hy926 cells treated by H2O2 under simulated microgravity, which was significantly inhibited by salidroside. There were six significant differentially expressed genes screened by transcriptome sequencing, including BCL‐2A1, FAM196B, TMEM158, PPP1R16B, CXCL8, PPP1R3B. RT‐qPCR results showed that BCL‐2A1 and FAM196B were consistent with the transciptome sequencing results, meanwhile, BCL2A1 and FAM196B genes were significantly increased after salidroside intervention in H2O2‐treated EA.hy926 cells under simulated microgravity. These results showed that apoptosis was induced significantly in H2O2‐treated EA.hy926 cells under simulated microgravity, which can be inhibited by salidroside, the active ingredient of Rhodiola rosea, through the regulation of BCL‐2A1 and FAM196B gene expression.Support or Funding InformationFunded by State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, grant No.SMFA14B01This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Actions of Nitric Oxide Synthase Inhibitors on Mitochondrial Respiration in Isolated Rat Heart Mitochondria
Authors: Dholakia Monica H. , Sakamuri Siva SVP. , Sure Venkata N. , Sperling Jared A. , Satou Ryousuke , Katakam Prasad VG. 
Published: June 2021

ObjectiveThe existence of a nitric oxide (NO) producing enzyme, nitric oxide synthase (NOS), within cardiac mitochondria has been speculated in the most recent decades. There is conflicting data regarding the identity, physiological function, and the pathophysiological significance of mitochondrial NOS. Nevertheless, mitochondrial preparations have been shown to display an ability to produce NO that is sensitive to NOS inhibitors. Our objective was to evaluate the impact of pharmacological NOS inhibition on mitochondrial respiration. We hypothesized that pharmacological inhibition of NOS affects mitochondrial respiration.Methods and ResultsMitochondria were isolated from rats by homogenization and gradient separation. Isolated mitochondria were divided into three groups: untreated control, neuronal NOS inhibitor‐treated (nNOS; ARL dihydrochloride or ARL), and endothelial NOS inhibitor‐treated (eNOS; N5‐(1‐Iminoethyl)‐L‐ornithine or NIO). Mitochondrial function was assessed by measuring oxygen consumption rates (OCR) using Seahorse XFe Analyzer. First, we observed that isolated rat heart mitochondria displayed respiratory control ratios above 2 suggestive of the acceptable tightness of the coupling between respiration and phosphorylation indicative of the good quality of the preparation. Second, both NOS inhibitors decreased the OCR related to ATP production and increased proton leak in the mitochondria although the basal and maximal respiration were unaffected.ConclusionsPharmacological inhibition of NOS impairs ATP production in isolated rat heart mitochondria that is likely to be related to increased proton leak. Thus, the physiological function of mitochondrial NOS activity involves modulation of inner mitochondrial membrane permeability to promote efficiency of ATP productionSupport or Funding InformationAmerican Heart Association (PVG: 14SDG20490359 and VNS: 16PRE31450006); National Institute of Health: National Institute of Neurological Disorders and Stroke and National Institute of General Medical Sciences (PVK: R01NS094834); and National Institute of Diabetes and Digestive and Kidney Diseases (RS: DK107694).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.