bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phosphatidylinositol (4, 5)‐bisphosphate coordinates functional interactions in the dopamine transporter to promote amphetamine behaviors
Authors: Aguilar Jenny , Shekar Aparna , Matthies Heinrich , Galli Aurelio 
Published: June 2021

The psychostimulant amphetamine (AMPH) mainly mediates its pharmacological and behavioral effects by increasing extracellular dopamine (DA) availability. DA homeostasis is maintained by the dopamine transporter (DAT), a presynaptic membrane protein that mediates the high‐affinity reuptake of released DA from the synaptic cleft. We have previously demonstrated that AMPH induces N‐term phosphorylation of the DAT, which leads to transport‐mediated efflux of DA. Furthermore, we have shown that phosphatidylinositol (4, 5)‐bisphosphate (PIP2) directly interacts with the DAT and facilitates AMPH‐induced DA efflux, but is not required for DA uptake. Specially, PIP2 binds DAT through electrostatic interactions with positively charged DAT N‐terminal residues. Disrupting the interactions between DAT and PIP2 or depleting PIP2 diminishes reverse transport (efflux) of DA. Previous studies on the human serotonin transporter show that non‐N‐terminal PIP2 binding sites (within the fourth intracellular loop) are essential for AMPH‐induced reverse transport of serotonin, but not substrate uptake. Together, these data led us to hypothesize that PIP2 coordinates functional interactions between the N‐terminus and the fourth intracellular loop to promote reverse transport of DA. Here, we demonstrate that depletion of PIP2 after DAT N‐terminus phosphorylation does not affect AMPH‐induced DA efflux, suggesting that N‐terminus phosphorylation is the limiting step of reverse transport of DA. Notably, we show that residue R443, which resides in the fourth intracellular loop, also modulates AMPH‐induced DA efflux. Thus, we focus on the role of the interaction between the DAT N‐terminus and R443 in mediating the reverse transport of DA. Furthermore, we translate our molecular discoveries in vivo by using a coordinated genetic and pharmacological approach to study AMPH‐induced behaviors in Drosophila melanogasterSupport or Funding Information1F31MH114316 (JIA), AHA Predoctoral Award (AS), DA035263(AG)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Automated detection of GPCR exocytic events reveals distinct recycling populations
Authors: Weinberg Zara Yael , Phan Tiffany , Puthenveedu Manojkumar A. 
Published: June 2021

G protein‐coupled receptors (GPCRs) are flexible scaffolds that allow cells to detect thousands of environmental signals. After binding ligand, receptor endocytosis enables cellular desensitization, after which the internalized receptor is sorted in the endolysosomal system for either degradation or recycling back to the plasma membrane. Throughout the postendocytic pathway, GPCRs continue to signal with different signals being attributed to differential endosomal localization of receptors during this process. Attempts to measure a given GPCR's recycling pathway have required perturbation of postendocytic dynamics through overexpression of specific marker proteins. We sought to understand receptor trafficking through the postendocytic pathway by looking for quantitative differences in individual recycling events that contained specific receptor cargos. Using three exemplar cargo –the GPCRs mu opioid (MOR) and B2‐adrenergic receptor (B2AR), and the classic endocytic cargo transferrin receptor (TfR) – we used total internal fluorescence microscopy to visualize individual exocytic events. We then analyzed these events by developing an automated analysis program which used supervised machine learning to discern and quantify discrete receptor exocytic events. We compared overall fluorescence intensity, event duration, and other quantitative characterizations of individual events. We discovered that TfR and B2AR recycle in a similar manner, while MOR recycled in a distinct manner with markedly less heterogeneity in its recycling population. These findings show that GPCR recycling offers another dimension through which receptors distinguish themselves, and suggest the value of measuring recycling as a potential means of dissecting a given receptor's signaling profile. Further, the tools developed in this study can be used to easily characterize the recycling phenotype of novel receptors, and can be extended to a variety of exocytic cargos.Support or Funding InformationSupported by University of MichiganThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Myosin IIa is the most important effector of zyxin in cAMP‐mediated endothelial exocytosis
Authors: Wei Guoqin , Li Pin , Chen Liangyi , Luo Jincai 
Published: June 2021

Endothelial exocytosis, one of the first lines of protection against vascular injury, is critical to maintaining the homeostasis of the blood vessels. Weibel‐Palade bodies (WPBs)1, endothelium‐specific secretory granules, deliver hemostatic and inflammatory mediators including von Willebrand factor (VWF) and P‐selectin in response to a variety of agonists2. Recently, using live‐cell super‐resolution microscopy3, we visualize the dynamic interaction between fine actin filaments and WPBs and found previously unappreciated reorganization of pre‐existing actin filaments around WPBs before fusion4. In addition, we show that focal adhesion protein zyxin mediates the formation of actin frameworks on exocytic WPBs4. However, the detailed mechanism how zyxin regulates the reorganization of actin filaments is still unknown.In this report, we combined protein interactomics, genetic screening, high‐resolution imaging, and animal models, to show that the direct interaction between myosin IIa and zyxin is essential for cAMP‐mediated endothelial VWF secretion.Using affinity purification and co‐immunoprecipitation assay, we found that myosin IIa is the most abundant interacting protein of zyxin. Surprisingly, besides the zyxin‐related function on exocytosis, myosin IIa plays vital roles in the regulation of blood vessels homeostasis. Downregulation of myosin IIa by shRNA significantly suppresses both forskolin‐ and epinephrine‐induced VWF secretion. Using an inducible endothelial specific myosin IIa null mice model, we observed impaired epinephrine‐stimulated VWF release, prolonged bleeding time and thrombosis from those mice. Mechanistically, we found that in resting cells, the loss of myosin IIa, inhibition of myosin activity and blocking the phosphorylation of myosin IIa at S1943 decreased the peripheral localization of Rab27‐positive WPBs along stress fibers. Following stimulation with cAMP activating agents, myosin IIa interacted with zyxin and this required the phosphorylation of S1916 on myosin IIa mediated by CK2 to support the formation of functional actin framework, facilitating fusion and subsequent exocytosis.In summary, our work revealed that myosin IIa is the most important interacting protein of zyxin, which couples the maintenance of mature WPB in peripheral region to the promotion of VWF secretion in synergy with zyxin via spatiotemporally distinctive actin remodelling using different phosphorylation sites (As shown in Figure 1). Our findings implicate myosin IIa as an important regulator of blood homeostasis under pathophysiological conditions.Support or Funding Informationthe National Science Funds(No. 91339111, No. 81470298, and Project 31521062), the Major State Basic Research Development Program of China (No. 2012CB945103), and the National Science and Technology Support Project (grant no. 2014BAI02B01).This 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 Bacterial Cell Wall Fragment Recognition by the Yeast Protein CYR1p
Authors: Scanlon Daniel J. , Burch Jason , Grimes Catherine 
Published: June 2021

Within the human body are trillions of microorganisms which must maintain a proper balance with the human host as well as amongst each other. These organisms must be able to accurately identify and respond to the bacterial cells that surround them. Pattern recognition receptors (PRRs) can bind pathogen associated molecular patterns (PAMPs) and enable these microorganisms to recognize their surrounding microbiome. Similarly, in yeast species Candida albicans the adenylyl cyclase CYR1p is found to bind muramyl dipeptide (MDP) a fragment of the bacterial cell wall or peptidoglycan. Bacterial cell wall fragments like MDP are interestingly found to trigger a phenotypical change in C. albicans to enter pathogenic hyphal growth through a cascade initiated by the binding of MDP to CYR1p. Another member of the Candida family, Candida glabrata has been found to not experience the same phenotypical switch to hyphal growth observed in C. albicans in the presence of MDP despite both species being of the same family and both commonly involved in yeast infections. The Leucine Rich Repeat (LRR) domain specifically has been shown to be the site of MDP binding within the protein CYR1p in C. albicans. To understand the differences in the mechanism of peptidoglycan recognition by C. albicans and C. glabrata, the LRR domain of C. glabrata was expressed and purified. Analysis of the binding or lack thereof between MDP and the LRR domain of CYR1p from C. glabrata could help to elucidate why C. albicans has hyphae growth triggered by MDP but C. glabrata does not.Support or Funding InformationUniversity of Delaware Department of Chemistry and BiochemistryThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Cross‐talk between Lipoprotein and Insulin Receptors in the Retina of Diabetic Mice
Authors: Sherman Josiah , El‐Desoky Dalia , Freter Robert , Adams Ryane , Mbony Hannah , Joseph Tiffany , Heron David , Hossain Ahamed , Bhattacharjee Partha 
Published: June 2021

Diabetic retinopathy (DR) is a visual complication of diabetes mellitus and a leading cause of visual impairment across the world. Retinal neurodegeneration has been shown to precede the vascular abnormalities of the retina that are used as key clinical indicators of DR. An important feature of retinal neurodegeneration associated with DR is apoptosis of the retinal ganglion cells (RGCs). Our previous in vivo studies with genetically modified db/db mice (mimicking human type 2 diabetes mellitus) indicate a lipid metabolism‐regulated signaling pathway involving lipoprotein receptor‐related protein 1 (LRP‐1) protecting RGCs against apoptosis. Specifically, activation of LRP‐1 by ligand apoEdp (dimerized LRP‐1‐binding apolipoprotein E derived peptide) regulates the PI3K/Akt pathway in the retina, which appears to be involved in cross‐talk with insulin receptor and N‐methyl‐D‐aspartate receptor (NMDAR) signaling. Excess NMDAR activation by neurotransmitter glutamate in DR promotes glutamate excitotoxicity, leading to apoptosis of the cell and thinning of the neuroretina. Recent in vitro studies using cultured RGCs from neonatal mice were conducted and suggest the role of LRP‐1 in regulating glutamate‐induced excitotoxicity in RGCs. Our preliminary data from these in vitro studies suggest that LRP‐1 stimulation via apoEdp results in reduced glutamate‐induced excitotoxicity in RGCs.Support or Funding InformationNIH BUILD TL4GM118968‐04NIH BUILD 5RL5GM118966‐04NIH MARC 2T34GM007716‐38This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Impaired Chemoreflex Response to Acute Hypoxia Correlates with Decreased Activation of the Medial Nucleus Tractus Solitarii in the STZ‐Induced Rat Model of Alzheimer's Disease
Authors: Brown Andrea G. , Thapa Mahima , Hooker John W. , Ostrowski Tim D. 
Published: June 2021

BackgroundAlzheimer's disease (AD) is the most common cause of dementia and clinically diagnosed largely based on cognitive decline. Most AD patients also present with disorders of respiration, swallowing, and autonomic function. Current studies suggest that pathological changes in the brainstem manifest simultaneously or even before those in forebrain regions, and may account for non‐cognitive symptoms. Identifying the pathologic changes in brainstem centers may elucidate the mechanisms behind cardiorespiratory dysfunction in AD. This study concentrated on the respiratory deficits. Using the streptozotocin (STZ)‐induced model of AD, we determined cell activation in response to acute hypoxia in the nucleus tractus solitarii (nTS), a brainstem area that is integral for chemoreflex function.MethodsSporadic AD was induced in Sprague Dawley rats (280 ± 17g, n = 6 rats/group) by intracerebroventricular injections of streptozotocin (1.5 mg/kg STZ in citrate buffer; day 1 and 3). Vehicle injections served as control (CTL). Peripheral chemoreflex function was tested with two hours of acute hypoxia (10% O2) in a plethysmography chamber. Immediately following the hypoxic period, the brains were fixed with 4% paraformaldehyde. Four representative areas of the nTS were immunohistochemically analyzed for cell activation (c‐Fos).ResultsThe chemoreflex‐mediated increase of minute ventilation in response to acute hypoxia was significantly blunted by ~20% in STZ rats when compared to CTL (p = 0.03). The diminished response continued over the entire 2 hours of hypoxia and was mainly due to alterations in respiratory rate. Immunohistochemical analysis revealed a ~25% decrease of hypoxia‐mediated cell activation in the medial nTS of STZ rats (−14.04 mm from bregma, p = 0.02). This decline in cell activation was not due to a general decrease in cell density as shown by DAPI staining. The level of activation in commissural and rostral nTS sections was not different from CTL.ConclusionWe had previously found respiratory dysregulation in the STZ model of sporadic AD. This follow‐up study analyzed respiratory parameters over a two‐hour hypoxic period and the underlying pattern of cell activation in the nTS. Our data document a reduced activation of the medial nTS in the chemoreflex pathway of AD rats. This finding may help explain the respiratory symptoms observed in AD patients.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
pharmABCology: an initiative to create logical mnemonics systems for learning drug names
Authors: Liang Willmann 
Published: June 2021

With a handful of comprehensive pharmacology textbooks on the market, students in any healthcare discipline are likely able to find at least one book that suits their individual needs. The more challenging part for students, however, is to become better acquainted with drug names. Textbooks seldom provide meaningful ways to help readers remember drug names and/or their mechanisms. Existing mnemonics, not widely used among students in general, may lack in providing the learner with an intuitive or logical approach to mentally connect with the drug names. For example, names of persons, objects or action verbs were chosen by random to represent a particular drug class or therapeutic drug use. The pharmABCology project was conceived with the final aim of creating logical mnemonics systems for drugs that students will commonly encounter in their studies. In this pilot presentation, two approaches, one based on the alphabet system and the other based on pharmacological mechanisms, were demonstrated in the mnemonics for four classes of drugs: 1) anti‐dyslipidaemics, 2) anti‐dysrhythmics, 3) anti‐hypertensives and 4) anti‐ischaemic drugs. For the alphabetical approach, the names, drug classes or mechanisms of anti‐dyslipidaemics and anti‐hypertensives are listed in alphabetical order. The other approach takes advantage of the spellings of anti‐dyslipidaemic and anti‐dysrhythmic drug names in formulating a meaningful sentence or phrase that is readily associated with the mechanisms of actions of these drugs. Some of the mnemonics systems above had been used in a sample (n = 30) of students in undergraduate MBChB tutorials, and the feedback was overwhelmingly satisfactory based on a 5‐point Likert scale. Of the 22 respondents (73 % response rate), 10 (45 %) and 9 (41 %), respectively, strongly agreed and somewhat agreed that pharmABCology mnemonics system helped with the learning of drug names. In light of the early promising results, similar approaches will be used to develop mnemonics for other drug classes with the intention of publicising this learning tool to the pharmacy, nursing and students in other healthcare‐related disciplines.Support or Funding InformationNilThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Will Use Of Cerego™ Spaced‐Learning And Self‐Test Sets Improve Medical Students' Performance On Summative Examination Pharmacology Questions?
Authors: Pham Grant , Quest Dale , Baatar Dolgor 
Published: June 2021

PURPOSESpaced learning means studying at intervals, and in contrast to cramming, seems to enhance knowledge retention. Electronic software applications are available for medical students to utilize that approach. Our aim was to determine if spaced learning modules administered via the free‐to‐use Cerego™ learning platform might improve performance on pharmacology questions in the Scientific Principles of Medicine course unit summative exam.METHODSMedical students were recruited from the Texas Tech University Health Sciences Center at El Paso, Paul L. Foster School of Medicine first‐year Class of 2020. The integumentary‐musculoskeletal‐peripheral nervous system (IMN) unit immediately preceded the cardiovascular‐respiratory (CVR) unit. No Cerego™ self‐test modules were created for IMN unit pharmacology sessions. Teaching materials for each of 7 CVR unit pharmacology sessions were used to generate 7 Cerego™ self‐test modules, each containing 10–45 questions approved by a faculty member, then made available to students on the Cerego™ learning platform. Cerego™ logs student attempts, time to complete a module, and an index of perceived difficulty. Subjects had unlimited access to Cerego™ while preparing for the CVR exam.RESULTSOne‐way ANOVA showed students performed better on the ten pharmacology multiple‐choice questions on the CVR summative examination than they did on the eight multiple‐choice questions on the IMN summative examination. Linear regression analysis showed no significant dependence of students' performance on CVR summative exam pharmacology questions on scores averaged for all seven Cerego™ sets (R2: 0.0057).CONCLUSIONThe results of this study question the potential for use of Cerego™ sets to enhance retention of pharmacology content. Similar projects showed Cerego™ sets improved anatomy and micro summative scores. The disparate results of these studies provide impetus to see whether using Cerego™ helps students improve knowledge retention and exam performance in behavioral science, biochemistry, genetics, histology, immunology, neuroscience, pathology and physiology.Support or Funding InformationAll research was done on campus without financial assistance from outside sources. The authors declare no conflict of interest.
Lack of Evidence for Methylenedioxypyrovalerone (MDPV)‐Induced Persistent Dopaminergic or Serotonergic Deficits: Comparison with Methamphetamine and Mephedrone
Authors: Magee Charlotte P. , German Christopher L. , Curtis Peter S. , Hanson Glen R. , Fleckenstein Annette E. 
Published: June 2021

β‐Ketoamphetamines such as methylenedioxypyrovalerone (MDPV) and mephedrone (MEPH) are synthetic cathinones with a structural similarity to methamphetamine (METH) that may account for some similarities in behavioral effects. However, the persistent effects of repeated high‐dose MDPV exposures on striatal dopaminergic and hippocampal serotonergic systems remain to be fully elucidated. Accordingly, the persistent effects of repeated high‐dose MPDV administrations were investigated. Results revealed that MDPV treatment did not alter striatal dopaminergic or hippocampal serotonergic systems as assessed 7 days later in synaptosomes prepared from treated rats. Further, MDPV did not alter hippocampal serotonin or 5‐hydroxyindoleacetic acid content at this time point. These data stand in contrast to our previous report that repeated high‐dose MEPH administrations cause persistent hippocampal serotonergic deficits. These data also stand in contrast to effects of repeated high‐dose METH administrations that include persistent striatal dopaminergic and hippocampal serotonergic deficits. Noteworthy, in these studies MDPV did not induce hyperthermia to the degree reported in previous studies of MEPH and METH. Further, the impact of MDPV on the dopamine transporter and vesicular monoamine transporter‐2 appears distinct from that of MEPH and METH. Taken together, these latter findings may contribute to the differential impact of MDPV, MEPH, and METH on dopaminergic and serotonergic systems.Support or Funding InformationDA039145 and DA031883This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Cannabidiol, a non‐psychoactive marijuana component, exhibits antioxidant and neuroprotective effects in neuronal Alzheimer's cell model SH‐5Y
Authors: Briggs Gwyneth Helen 
Published: June 2021

Cannabidiol, a non‐psychoactive marijuana component, is a pleotropic PPAR‐gamma agonist which exhibits antioxidant and neuroprotective effects in several experimental models. Amyloid beta (Aβ), the precursor to extracellular senile plaques, has been implicated in the development of cognitive impairment and neuronal cell death. The effect of Cannabidiol against AD pathology has been linked to its ability to attenuate Aβ and tau aggregation in vitro. The present study evaluates the neuroprotective action of Cannabidiol on Aβ‐induced oxidative stress and memory loss. Differentiated SH‐SY5Y neuronal cell lines were pretreated with cannabidiol followed by Aβ treatment for 24 hours. SHSY5Y cells treated with Aβ exhibited increased reactive oxygen species and lipid peroxide levels. Enzymatic antioxidants including superoxide dismutase, catalase and glutathione reductase were decreased in the Aβ treated group when compared to the control group. Aβ treatment also increased the expression of total tau as well as phosphorylated forms of tau (CP13, S202/205; PHF1, S396/404). Expression of PSD‐95 and Arc proteins, essential for synaptic maturity and plasticity, was decreased by Aβ treatment. Cannabidiol treatment attenuated the accumulation of lipid peroxide levels, up‐regulated the antioxidant activities and improved the expression of memory‐associated proteins in Aβ treated SHSY5Y cells. Mechanistic study using SH‐SY5Y cell line transfected with APP695 (SH‐SY5Y‐APP) to investigate the Aβ ameliorating effects of cannabidiol showed no changes in protein levels of APP, α‐secretase or gamma secretase activity. In contrast, cannabidiol decreased β‐secretase levels and inhibited its activity thereby leading to reduced Aβ levels. These results suggest that Cannabidiol is capable of improving antioxidant activity, mitochondrial energy regulation, while decreasing Aβ, thereby indicating it to be a lead compound for AD drug development.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.