bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatially and Temporally Distinct Encoding of Muscle and Kinematic Information in Rostral and Caudal Primary Motor Cortex
Authors: Kolasinski James , Dima Diana C , Mehler David M A , Stephenson Alice , Valadan Sara , Kusmia Slawomir , Rossiter Holly E
Published: April 2020

The organizing principle of human motor cortex does not follow an anatomical body map, but rather a distributed representational structure in which motor primitives are combined to produce motor outputs. Electrophysiological recordings in primates and human imaging data suggest that M1 encodes kinematic features of movements, such as joint position and velocity. However, M1 exhibits well-documented sensory responses to cutaneous and proprioceptive stimuli, raising questions regarding the origins of kinematic motor representations: are they relevant in top-down motor control, or are they an epiphenomenon of bottom-up sensory feedback during movement? Here we provide evidence for spatially and temporally distinct encoding of kinematic and muscle information in human M1 during the production of a wide variety of naturalistic hand movements. Using a powerful combination of high-field functional magnetic resonance imaging and magnetoencephalography, a spatial and temporal multivariate representational similarity analysis revealed encoding of kinematic information in more caudal regions of M1, over 200 ms before movement onset. In contrast, patterns of muscle activity were encoded in more rostral motor regions much later after movements began. We provide compelling evidence that top-down control of dexterous movement engages kinematic representations in caudal regions of M1 prior to movement production.
New Findings on the Resistance Mechanism of an Elite Diploid Wild Potato Species JAM1-4 in Response to a Super Race Strain of Phytophthora infestans
Authors: Zheng Jiayi , Duan Shaoguang , Armstrong Miles R. , Duan Yanfeng , Xu Jianfei , Chen Xinwei , Hein Ingo , Jin Liping , Li Guangcun
Published: April 2020

Late blight is a devastating potato disease worldwide, caused by Phytophthora infestans. The P. infestans strain 2013-18-306 from Yunnan is a “supervirulent race” that overcomes all 11 known late blight resistance genes (R1 to R11) from Solanum demissum. In a previous study, we identified a diploid wild-type potato JAM1-4 (S. jamesii) with high resistance to 2013-18-306. dRenSeq analysis indicated the presence of novel R genes in JAM1-4. RNA-Seq was used to analyze the late blight resistance response genes and defense regulatory mechanisms of JAM1-4 against 2013-18-306. Gene ontology enrichment and KEGG pathway analysis showed that many disease-resistant pathways were significantly enriched. Analysis of differentially expressed genes (DEGs) revealed an active disease resistance mechanism of JAM1-4, and the essential role of multiple signal transduction pathways and secondary metabolic pathways comprised of SA-JA-ET in plant immunity. We also found that photosynthesis in JAM1-4 was inhibited to promote the immune response. Our study reveals the pattern of resistance-related gene expression in response to a super race strain of potato late blight and provides a theoretical basis for further exploration of potato disease resistance mechanisms, discovery of new late blight resistance genes, and disease resistance breeding.
A Road Less Traveled: Trafficking Hydrogen Sulfide and B12
Authors: Banerjee Ruma
Published: April 2020

Similar in their very low intracellular abundance, the metabolism of hydrogen sulfide (H2S) and vitamin B12 intersect at the sulfur mobility in PPD network where B12 serves as a cofactor, and H2S spews from enzymes with relaxed specificity. While only two mammalian enzymes require B12 for activity, cells maintain a regiment of chaperones to tailor and escort B12 from its point of entry into the cell to its targets. During this inter‐compartmental voyage, B12 is translocated between active sites in transient protein‐protein complexes, which exhibit the artful use of coordination chemistry. Structural enzymology studies on trafficking proteins are providing molecular insights into the cellular strategies for moving this portly organometallic cofactor. While the metabolic activity of gut microbiota represents a limited source of B12, it is a substantial source of H2S and necessitates adaptations by host cells to routine exposure to this respiratory toxin. Our studies are revealing the metabolic reprogramming that is part of the stress response to H2S in colon epithelial cells. Thus, although low in abundance, B12 and H2S have profound impacts on cellular biochemistry.

Support or Funding Information

National Institutes of Health (DK45776, HL58984, GM112455)

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Hepatic perilipin 5 promotes lipophagy and alters lipid droplet and mitochondrial dynamics
Authors: Zhang Enxiang , Najt Charles P , Hu Hongbo , Mashek Douglas G.
Published: April 2020

Lipid droplets (LDs) are energy‐storage organelles which are composed of a lipid core, mainly triacylglycerol, surrounded by a phospholipid monolayer. In addition, LDs are coated with hundreds of proteins including members of the perilipin family. Perilipin 5 (PLIN5) is highly expressed in oxidative tissues including the liver and in response to fasting. PLIN5 is thought to play a key role in uncoupling LD accumulation for lipotoxicity and mitochondrial dysfunction. It is generally accepted that PLIN5 influences LDs turnover through its binding and inhibition of lipolytic enzymes and also bridges LDs and mitochondria, which is thought to facilitate fatty acid transfer. The objective of these studies was to characterize the mechanism through which PLIN5 influences hepatic LD turnover in fed and fasting conditions. We employed anti‐sense oligonucleotides to ablate hepatic PLIN5 in vivo and used overexpression and knockdown approaches in primary hepatocytes. Both in vitro and in vivo studies revealed that PLIN5 ablation blocked autophagy and lipophagy, the lysosomal degradation LDs. Using autophagy inhibitors, we found that PLIN5 promoted autophagic flux, LD turnover and oxidation of LD‐derived fatty acids under fasting conditions. Moreover, we isolated cytosol and LD‐associated mitochondria and measured rates of fatty acid oxidation and protein expression. Cytosolic mitochondrial had increased fatty acid oxidation and expression proteins involved in fatty acid/oxidative metabolism, but ablation of PLIN5 normalized the differences between the two mitochondrial populations. In conclusion, PLIN5 promotes autophagy/lipophagy to influence LD turnover and plays a critical role in mitochondrial oxidative metabolism.

Support or Funding Information

National Institute of diabetes and digestive and kidney diseaseAmerican diabetes accociationNational Instituite on aging National Natural Science Foundation of China (NSFC 31671945)China Scholarship Council

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The neurovascular contents of a unilateral double mandibular canal: A case study
Authors: Ramirez Kristen Renee
Published: April 2020

The occurrence of bifid mandibular canals is unusual but not rare. Previous reviews and case studies have described numerous types of bifid canals based on location, anatomy, and contents. Developmentally, ossification of the mandible begins at the region of the mental foramen and continues posteriorly, forming the mandibular canal around the neurovascular bundle within. This process explains the creation of multiple mandibular canals and the diversity of canal types previously recorded in the literature; the inferior alveolar nerve originates as three distinct bundles and may experience incomplete fusion, or the nerve and artery may be isolated during ossification. However, the presence of two distinct mandibular canals, each originating from its own mandibular foramen, is even more unusual. This case report describes a unilateral variant discovered during the dissection of a 92‐year‐old African American female. On the left side, the cadaver presents two distinct mandibular canals, each containing a branch of the maxillary artery and mandibular nerve, the third division of the trigeminal (CN V). The nerves within the two canals, the inferior alveolar nerve in the superior canal and the mental nerve in the inferior canal, were distinct from each other at the level of the posterior division of the mandibular nerve, within 1 cm of foramen ovale in the infratemporal region. This is the first description of such an occurrence, and emphasizes the need for identification of the contents of a bifid or accessory mandibular canal prior to invasive procedures.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Basigin gene products associate to form a novel cell‐adhesion system used to maintain a metabolic cytoarchitecture and potentially stimulate an immune response in the neural retina
Authors: Gonzalez Alicia , Ochrietor Judith D
Published: April 2020

Two Basigin gene products are expressed in the vertebrate neural retina, named Basigin‐variant‐ 1 and Basigin‐variant‐2. Variant‐2 is found on cells throughout the body, including monocytes, as well as on the surface of Muller glial cells and retinal pigmented epithelial cells of the mammalian eye, whereas variant‐1 is considered a photoreceptor‐specific gene product. These membrane‐associated glycoproteins, which are members of the immunoglobulin (Ig) superfamily, are identical in amino acid sequence except for an additional Ig domain at the amino terminus of Basigin‐variant‐1. The amino acid sequence of the Basigin‐variant‐1‐specific Ig domain is well conserved throughout evolution, which suggests that it performs a conserved function. In addition, the Basigin‐variant‐1‐specific Ig domain is similar in amino acid sequence to a region of L1cam, a known Basigin‐variant‐2 binding partner in the brain. Therefore, the purpose of this study was to test the hypothesis that the Basigin‐variant‐1‐specific Ig domain binds to Basigin‐variant‐2. Recombinant forms of the Basigin‐variant‐1‐specific Ig domain and L1cam were generated via molecular techniques and used in enzyme‐linked immunosorbent assay (ELISA) binding assays with Basigin‐variant‐2 endogenously expressed in mouse neural retina and kidney, as well as the mouse monocytic cell line RAW 264.7. The results of the study indicate that the Basigin‐variant‐1‐specific Ig domain does bind Basigin‐variant‐2 with moderate affinity. The corresponding region of L1cam, however, does not interact with Basigin‐variant‐2, which suggests that amino acids within this highly conserved domain that are specific to Basigin‐variant‐ 1 but not L1cam are responsible for the interaction. The data suggest that Basigin‐variant‐1 does interact with Basigin‐variant‐2 to form a novel cell adhesion system between Müller cells and photoreceptors in the neural retina. The data also suggest that the same interaction can occur between Basigin‐variant‐1 on photoreceptor cells and Basigin‐variant‐2 on monocytes that invade the neural retina in response to a compromised retinal pigmented epithelium.

Support or Funding Information

UNF Office of Academic Affairs

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Epitope Characterization and Design of Epitope Binding Proteins for Idiopathic Membranous Nephropathy: New Tools for Autoimmune Kidney Disease Therapy
Authors: Goldman Liam , Stocks Omar , Stoddard Shana V.
Published: April 2020

In autoimmune diseases antibodies incorrectly attack normal healthy cells, which can promote degradation of tissues and can lead to long‐term disease and death. Modern clinical therapies treating autoimmune disease include the use of immunosuppressive medicines. Although this therapy has shown success in slowing down the progression of autoimmune disorders, this treatment diminishes the patient's entire immune system's ability to fight off normal pathogens. This highlights the need for more specific treatment options for autoimmune disease that do not weaken the patient's entire immune system. Primary membranous nephropathy (PMN) is a kidney specific autoimmune disease currently being treated with immunosuppressive medicines. In patients with PMN, seventy percent of individuals produce autoantibodies that target the phospholipase A2 receptor (PLA2R). The goal of this research is to design PLA2R specific binding proteins (epitope caps) that will prevent the PLA2R autoantibodies from binding to the C‐type lectin domain number seven (CTLD7) on this antigen. Using Epitopia and EPCES, three possible epitope sites were identified and characterized. Binding strength of the binding proteins to the CTLD7 was measured through Rosetta Online Server that Includes Everyone. In silico mutations were made to the Monobody template 5FXB. Currently, we have produced three epitope caps (5FXB‐001‐LVG, 5FXB‐002‐LVG, 5FXB‐003‐LVG) with binding scores that are below out targeted binding score of −5.0 Rosetta energy units (REU). Currently protein expression and purification is underway to permit further evaluation of the epitope caps using ELISA assays to determine experimental binding proficiency. Furthermore, this research could provide patients with more specific methods of treatment for autoimmune disease than the contemporary treatment options such as, immunosuppressive therapies.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mechanism of a membrane ‘transceptor’: A transporter and a receptor in one
Authors: Gupta Meghna , Stroud Robert
Published: April 2020

Certain transporter‐like membrane proteins also act as receptors for the availability of external nutrient content in eukaryotic cells, hence called ‘transceptors’. The concept came into the picture when several transporter‐like receptors were discovered in eukaryotes. They can be classified as transporting (example yeast Mep2, Gap1, Pho84, mammalian SNAT2) and non‐transporting (example yeast Snf3, Rgt2, mammalian SGLT3) transceptors based on their ability to transport the substrate. I sought to determine the mechanisms by which a key phosphate transceptor combines these dual functions at the level of atomic structure and biochemistry. Phosphate is an essential macronutrient for structural and metabolic requirements of all eukaryotic cells; for nucleotide and lipid biosynthesis, cell signaling by phosphorylation and energy storage (ATP), and because of its impact, pathways inside the cell must respond to availability even outside the cell, in a regulated fashion. I selected the phosphate transceptor PiPT from Piriformospora indica, for which structure is available in atomic details, the first for any transceptor. This enabled the mutagenesis of regions as a test of their transport and/or receptor function, and further structure analysis aimed at probing the signaling pathway across the membrane. Compounds known to inhibit transport and/or activate the receptor function were tested and used to distinguish between the two functions. Site‐directed mutagenesis based on the available structure was exploited to determine the role of residues that bind phosphate in the central transport site and to define the alternate access to both sides of the membrane, and the separate pathway for protons and the way their transport is absolutely coupled to phosphate transport. Transport assays and biochemical assays probing the intracellular signaling response for the mutants studied assisted in determination of a possible mechanism of transport and receptor function.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Role of interleukin‐1 receptor‐associated kinase 4 in drug addiction
Authors: Wu Ruyan , Liu Jian‐Feng , Vu Jimmy , Johnson Bernard , Li Jun‐Xu
Published: April 2020

Drug addiction remains an unmanageable and costly disease. Apart from neuronal adaptation, growing recognition arises that glial proinflammatory activation importantly contributes to the rewarding effects of multiple drugs of abuse. Recent studies suggest the central importance of Toll‐like receptor 4 (TLR4), a candidate neuroimmune therapeutic target for drug addiction. While Interleukin‐1 receptor associated kinase 4 (IRAK4) plays a crucial role in TLR4 mediated innate immunity, there is no further studies support its functioning in drug addiction. We hypothesized that drug‐taking activates IRAK4 and induces reinforcing effects, and disruption of IRAK4 signaling attenuates the addictive behaviors. In the present study, IRAK4 and IRAK1 phosphorylation after morphine and cocaine self‐administration was evaluated using western blotting. The role of IRAK4 in morphine self‐administration and cue‐induced reinstatement was examined with its inhibitor, PF06650833. Moreover, local pharmacological manipulation was conducted to determine the role of IRAK4 in the nucleus accumbens (NAc) core in the cue‐induced reinstatement of morphine seeking. We found that morphine self‐administration significantly increased the phosphorylation of IRAK4, but not IRAK1, both in NAc and VTA. However, neither cocaine short access nor long access self‐administration had any effect on the phosphorylation of IRAK4. Systemic administration of PF06650833 significantly attenuated cue‐induced reinstatement of morphine seeking without affecting the spontaneous locomotion in rats, and microinjection of PF06650833 into NAc core sufficiently decreased cue‐induced morphine reinstatement. These results demonstrated that modulation of IRAK4 activity regulates the cue‐induced morphine reinstatement, and suggested it as a novel candidate target in treating drug addiction.

Support or Funding Information

This work was supported by NIDA [Grant R21DA040777].

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The role of autophagy in mesenteric arteries from hypertensive rats
Authors: Kwon Youngin , Choi Soo‐Kyoung , Byeon Seonhee , Lee Young‐Ho
Published: April 2020

Autophagy is an intracellular degradation system that disassembles cytoplasmic components through autophagosomes with lysosomes. Autophagic dysregulation may be related vascular diseases including hypertension, pulmonary hypertension and atherosclerosis. Recently, there are increasing interests about involvement of autophagy in survival and function of vascular smooth muscle cells. In hypertensive rat, impaired relaxation and augmented contraction elevate peripheral resistance. We observed expression levels of autophagic markers beclin1, LC3I/II and p62 in mesenteric arteries and aorta from control rats and hypertensive rats. Significantly increased beclin1 and LC3II were observed in hypertensive rats compared with control rats. We checked the expression level of p62, autophagosome cargo protein, which is degraded by autolysosomes. The level of p62 was significantly decreased in hypertensive rats. In this study, we assumed that alterations in autophagic flux change function of mesenteric arteries from hypertensive rats.

Support or Funding Information

This work was supported by the Basic Science Research Program of the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF‐2018R1D1A1B07041820) and Brain Korea 21 PLUS Project for Medical Science, Yonsei University.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Functional significance of O‐GlcNAcylation of ICln in the regulation of cellular volume
Authors: Remigante Alessia , Costa Roberta , Civello Davide , Morabito Rossana , Nagy Tamas , Marino Angela , Dossena Silvia
Published: April 2020

O‐GlcNacylation (O‐GlcNAc) is a post‐translational modification of serine or threonine residues of nuclear and cytoplasmic proteins and occurs via conjugation to a single monosaccharide, the N‐acetylglucosamine. O‐GlcNAc modification intervenes in a wide variety of physiological and pathological processes, and negatively affects the regulation of cellular volume with a molecular mechanism still unknown. Recently, the protein ICln, crucial in the activation of a chloride conductance (IClswell) after anisosmotic cell swelling, has been found to be O‐GlcNacylated. Mass spectrometry and bioinformatics show multiple O‐GlcNAc modification sites, of which the impact on ICln function is unknown. To explore the functional significance of O‐GlcNAc modification of ICln, the wild type and different mutant forms of ICln have been expressed in a heterologous system and characterized by whole‐cell patch‐clamp in the presence of normal or elevated O‐GlcNAc levels. The results show that: I) O‐GlcNAc elevation suppresses the ICln‐induced current; II) IClnT223A is functional and sensitive to O‐GlcNAc elevation; III) IClnS193X loses most of its activity, though the residual current is sensitive to O‐GlcNAc elevation; IV) IClnS67A is functional but insensitive to O‐GlcNAc elevation; V) the IClnS67T‐induced current is lower compared to the wild type, and is no longer responsive to O‐GlcNAc elevation. Overall, the evidence obtained indicates that O‐GlcNAcylation of ICln at the level of Serine 67 leads to suppression of the ICln‐induced current and may disclose the mechanism by which O‐GlcNAc elevation alters the regulation of cellular volume. We suggest that the protein ICln may represent a novel target in the prevention or treatment of pathological states characterized by chronically elevated O‐GlcNAcylation levels

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mast Cells and Macrophages of Rats lungs in an Acute Model of Fat Embolism
Authors: Lin Jane Hua‐fang , Egdebe Joy , Hamidpour Soheila , Omoscharka Evanthia , Haferkamp Thomas , Lind Taylor , Spaedy Abigail , Silswal Neerupma , Pour Mohammad , Poisner Alan , Moneghan Paula , Molteni Agostino
Published: April 2020

Introduction

Fat embolism (FE) by IV injection of Triolein (T) causes vasculitis, septal inflammation and fibrosis in rat lungs at 48 hours, which is mitigated by two drugs acting on the renin‐angiotensin system (RAS) Captopril and Losartan. An increase in mast cells is noted following administration of T, with an even higher increase by concomitant treatment with Captopril and significant induction by Losartan. This study examines the presence and number of macrophages in rat lungs after T treatment with or without addition of Captopril and Losartan.

Methods

Sprague‐dawley rats (280–300g) were treated with 0.2 ml IV T or saline. One hour later 0.2 ml of Saline, Captopril, or losartan was administered IP in the 3 T subgroups. All rats were necropsied 48 hours later under isoflurane anesthesia. Lungs were fixed in 10% formalin and stained with: 1. hematoxylin eosin for morphology, 2. trichrome for fibrosis, 3. CD 117 for mast cells and 4. CD 68 for macrophages. Two pathologists unaware of slide identity reviewed ten random photographs of all slides at 400x for macrophage count and histopathological evaluation. Slide photographs and mast cell count was performed by 2 other pathologists.

Results

As previously reported, T injection induced pulmonary vasculitis, septal inflammation and fibrosis which was markedly reduced by the RAS inhibitors Captopril and Losartan. Contrary to the statistically significant increase of mast cells after these 3 treatments, macrophage counts were only increased but minimally by T and T + Captopril. T + Losartan administration yielded a macrophages count similar to that of the saline controls.

Two types of macrophages were observed: one composed of small cells with compact cytoplasm and nucleus, similar in their size to the size of the mast cells and a second type with a larger vacuolated cytoplasm. The number of cells of this second group was rather small, so that any increase of these cells could not influence the macrophages total number.

Conclusion

Both mast cells and macrophages play a determinant role in the pathogenesis of the inflammatory and fibrotic pulmonary damage after T fat embolism. A different response to the injury was observed between the numbers of these two series of cells in the earlier phase of the injuries. The difference also observed in mast cells versus macrophages number present following T + Captopril and T + Losartan administration, suggesting a diversely regulated pharmacologic activity of the Renin Angiotensin System of the two drugs in the protection of the fat embolism mediated damage.

Support or Funding Information

Funded and supported by the Catherine T. Geldmacher Foundation St. Louis, Missouri.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Inhibition of phosphodiesterase‐4D reverses memory deficits and depression‐like effects via cAMP signaling in mouse models of Alzheimer's disease
Authors: Zhang Hanting , Wang Hao , Zhang Fangfang , Li Bing , Zhou Yanmeng , Yu Haiyang , Xu Ying , O'Donnell James
Published: April 2020

Depression is highly correlated with Alzheimer's disease (AD), but treatment for the comorbidity of both is lacking. Phosphodiesterase‐4 (PDE4), an enzyme that catalyzes the hydrolysis of cyclic AMP (cAMP), has been considered as a promising target for treatment of both memory loss in AD and depression. Using mouse models of AD and potent PDE4 inhibitors and PDE4‐subtype knockout mice, we demonstrated that PDE4D plays a role in the comorbidity of memory loss and depression in AD. Treatment with the PDE4 inhibitor rolipram or roflumilast reversed memory deficits in novel object recognition and Morris water‐maze tests in APP/PS1 double transgenic and 3xTg‐AD mice, which are widely used models for AD. Similarly, in the tail‐suspension and forced‐swimming tests, the PDE4 inhibitors reversed the decreased immobility in AD mice, suggesting antidepressant‐like effects. The effects of PDE4 inhibitors were mimicked in the tests using mice deficient in PDE4D, which displayed memory‐enhancing and antidepressant‐like effects, relative to the WT mice microinfused with beta‐amyloid peptide 1–42 into the hippocampus. In addition, the PDE4 inhibitor treatment reversed the decreased ratio of Bcl‐2/BAX and inhibited the increased expression of PDE4D in the cerebral cortex and hippocampus of AD mice. Further, the PDE4 inhibitors reversed the decreased levels of cAMP and expression of phosphorylated cAMP response element‐binding protein (CREB) and brain derived neurotrophic factor (BDNF) in AD mice. These were mimicked by PDE4D deficiency and treatment with a PDE4D relatively selective inhibitor. In conclusions, these results suggest that PDE4 is an important target for the comorbidity of memory loss and depression in AD, which appears to be mediated by PDE4D‐cAMP signaling.

Support or Funding Information

This work was supported by research grants from NIH/NIA AG031687 and NIH/NIAAA HHSN275201700001C (both to HTZ) and the National Natural Science Foundation of China (81441111 to HW)

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Ethanol Leaf Extract of Moringa Oleifera Blunts Isoproterenol‐induced Cardiotoxicity in Rats through Mitigation of Free Radical Production and Down Regulation of Cardiac Troponin and Nuclear Factor Kappa B
Authors: Adedapo Adeolu Alex , Asunloye Oluwatosin O , Adeoye Bisi Olajumoke , Oyagbemi Ademola A , Omobowale Temidayo O , Falayi Olufunke Olubunmi , Ogunpolu Blessing Seun , Oguntibeju Oluwafemi Omoniyi , Yakubu Momoh Audu
Published: April 2020

Moringa oleifera is a plant that is widely distributed in the tropical environment and is used for medicinal purpose. It is believed that every part of this plant has medicinal value. The study evaluated the effect of the ethanol leaf extract of Moringa oleifera (EMOL) on isoproterenolinduced myocardial infarction in rats. Thirty‐five male Wistar rats weighing between 100 and 160 mg/kg were used for the study. The rats were randomly divided into 5 groups of 7 animals per group. Group A (control) animals were given normal saline, Group B (Toxicant) animals were given 100 mg/kg of isoproterenol administered subcutaneously on day 8. Groups C and D animals were given 50 mg/kg and 100 mg/kg of ethanol leaf extract of Moringa oleifera (ELMO) respectively for 7 days and on day 8 were given 100mg/kg of isoproterenol. Group E animals received 100 mg/kg of Moringa oleifera only for 7 days. On day 9 blood sample was taken for serum analysis of CK‐MB, Myeloperoxidase, Nitric oxide and Total protein, thereafter the animals were sacrificed via cervical dislocation and heart harvested for biochemical assays for the analysis of Advanced oxidative protein product (AOPP), Protein Carbonyl (PC), Malonaldehyde (MDA), Superoxide dismutase (SOD), Glutathione‐S‐Transferase (GST), Reduced glutathione (GSH), Glutathione peroxidase (GPx), Total thiol, Non‐protein thiol and Hydrogen peroxide (H2O2) generation), histopathology and immunohistochemistry (CTnI, NF‐KB).

In this study there is significant (p < 0.05) reduction in SOD, GPx, GST, increased AOPP, PC, MDA, MPO levels and H2O2 generation in toxicant group (group B) but there was corresponding increase in the antioxidant enzymes and decrease in markers of oxidative stress and inflammation in ELMO treated groups. The toxicant also caused severe histopathological changes in the heart tissues but these were corrected by all the doses of the extract. There was increase expression of CTnI and NF‐KB in the toxicant group; pre‐treatment with ELMO however caused significant down regulation of all these proteins signifying its anti‐inflammatory and anti‐oxidative property.

In conclusion, these experiments showed that ethanol leaf extract of Moringa oleifera possess cardiac protective effect through mitigation of free radicals production and down regulation of the studied cytokines.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Stretch‐induced activation of Hippo signaling in lung microvascular endothelial cells: A novel mechanism of overventilation‐induced pulmonary fibrosis
Authors: Turki Razan , Kapus Andras , Kuebler Wolfgang
Published: April 2020

Introduction

Mechanical ventilation is a mainstay of current therapy for patients with acute respiratory distress syndrome (ARDS). Yet despite its benefits, mechanical ventilation can also cause ventilator‐induced lung injury (VILI) that may ultimately progress to pulmonary fibrosis. In this study, we aimed to elucidate cellular mechanisms by which mechanical ventilation triggers pulmonary fibrosis. Specifically, we focused on the mechanosensitive transcriptional co‐factor TAZ, a key player in the Hippo‐signaling pathway involved in mechanosensation, cell proliferation, and profibrotic responses. As such, TAZ translocates to the nucleus of fibrotic lungs but not in healthy tissue. Interestingly, TAZ distribution upon cyclic stretch has not been extensively characterized and the underlying mechanisms are not well defined.

Objectives

To examine the effect of mechanical stretch on the nuclear translocation of TAZ in endothelial cells, and to identify underlying regulatory mechanisms.

Methods

To mimic the effects of mechanical overventilation, human pulmonary microvascular endothelial cells (HPMECs) were subjected to stretch regimens at either 5%, mimicking low tidal volume ventilation, or 18% mimicking high tidal volume ventilation at 0.25 Hz for 1,3,6, 12h on a Flexcell 5000 Tension System and compared to static control (0%).

Results

Mechanical stretch induced expression and release of the profibrotic cytokine TGF‐β1 from HPMECs and concomitantly caused translocation of TAZ from the cytosol to the nucleus in a dose‐ and time‐dependent manner. Specifically, the nuclear to cytoplasmic ratio (N/C) of TAZ increased after 3h of stretch at 18% compared to the static control whereas stretching these cells at 5% increased TAZ nuclear localization after 6h. Stretch‐induced TAZ translocation was not prevented by pharmacological inhibition of JNK or Src kinases, known regulators of the Hippo kinase LATS2; yet TAZ translocation was blocked by inhibition of Aurora kinases with SNS 314 mesylate (10UM). Consistently, inhibition of Aurora kinases decreased LATS2 phosphorylation at Ser83, a known modulation site of LATS2 activity.

Conclusion

These data suggest that mechanical stretch activates TAZ and triggers release of pro‐fibrotic cytokines, at least partly, in an Aurora kinase and LATS2‐dependent mechanism. Interventions targeted at the Hippo‐signaling pathway as well as its upstream regulation may provide potential strategies to counteract the detrimental effects of mechanical ventilation.

Support or Funding Information

This work was supported by the Canadian Institutes of Health Research.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
ACUTE EFFECT OF ALDOSTERONE ON THE MEMBRANE POTENTIAL IN NEURONS OF THE NUCLEUS OF THE SOLITARY TRACT
Authors: Menegaz Danusa , Karlen‐Amante Marlusa , Fazan Frederico Sassoli , Varanda Wamberto Antonio , Menani José Vanderlei , Zoccal Daniel Breseghello , de Almeida Colombari Debora Simões , Colombari Eduardo
Published: April 2020

Introduction

A population of neurons in the nucleus of the solitary tract (NTS) expresses both the mineralocorticoid receptor (MR) and the enzyme 11β‐hydroxysteroid dehydrogenase type 2 (HSD2), making these neurons responsive to aldosterone, not to glucocorticoids. HSD2 neurons in the NTS contribute to the development of sodium appetite which is stimulated by a combination of body sodium deficiency and low blood volume, a condition that activates the renin‐angiotensin‐aldosterone system. The effect of aldosterone in the NTS to induce sodium appetite may involve non‐genomic mechanisms, independent of nuclear MR, gene transcription and protein synthesis.

Objective

In the present study, we investigated the acute effect of aldosterone on the membrane potential of NTS neurons in brainstem slices of rats.

Methodology

Male Holtzman rats (150 to 250 g) were decapitated and the brainstem rapidly removed and submerged in ice‐cold artificial cerebrospinal fluid (aCSF) with osmolality of 300–310 mosmol/KgH2O and pH 7.4. Brainstem coronal slices were obtained and then placed in the recording chamber, which was continuously perfused with oxygenated aCSF with or without aldosterone at room temperature. Whole‐cell patch‐clamp recordings of NTS neurons were done in current‐clamp mode to measure the membrane potential. Data are shown as mean ± SEM, and statistical significance was determined by unpaired Student's t‐test using the GraphPad Prism software. Experimental protocols were approved by the Ethics Committee for Animal Care and Use (CEUA 13/2018).

Results

Aldosterone (1 □M) caused cell depolarization and increased firing frequency of action potentials (0.8 ± 0.2 Hz, *** p < 0.001), in silent NTS neurons. Only 30% of the recorded neurons (6 of 20 neurons) showed a reversible depolarization in response to aldosterone and repolarization upon washout.

Conclusion

The present results suggest that aldosterone, acting via non‐genomic mechanisms, can depolarize and increase the firing frequency of action potentials in NTS neurons in vitro. These cells (possibly HSD2 neurons) might be those involved in the development of sodium appetite induced by aldosterone.

Support or Funding Information

Funding: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP).

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of Dynamic Arm and Leg Exercise on Muscle Sympathetic Nerve Activity and Vascular Conductance in the Inactive Leg
Authors: Millar Philip J , King Trevor J , Incognito Anthony V , Lee Jordan B , Shepherd Andrew D , Cacoilo Joseph A , Slysz Joshua T , Burr Jamie F , Doherty Connor J
Published: April 2020

The aim of this study was to comprehensively assess the effects of rhythmic handgrip (RHG), one‐leg cycling, and concurrent arm and leg exercise on muscle sympathetic nerve activity (MSNA) and vascular conductance responses in the inactive leg. Thirty‐five participants completed two study visits in a randomized order. During visit 1, hemodynamic (Finometer) and superficial femoral artery (SFA) blood flow (Doppler ultrasound) measurements were assessed at rest and during 3 min of RHG (1:1 duty cycle; 40% MVC), one‐leg cycling (17 ± 3% peak power output), and concurrent exercise at the same intensities. During visit 2, hemodynamic and MSNA (fibular nerve microneurography) measurements were acquired during the same exercise modes (MSNA; n=12). SFA blood flow and MSNA were both acquired in the inactive leg. Heart rate, blood pressure, cardiac output, and respiration rate increased during each exercise mode (all, P<0.0001), with the largest increases during concurrent exercise (all, P<0.006); no differences were detected between visit 1 and 2 (all, P>0.05). SFA mean blood flow increased during RHG (Δ24 ± 30 ml/min, P<0.0001) and concurrent exercise (Δ10 ± 38 ml/min, P=0.03) but not cycling (Δ2.3 ± 30 ml/min, P=0.9). SFA vascular conductance was unchanged during RHG (Δ0.02 ± 0.29 ml·min−1·mmHg−1, P=0.9) but reduced similarly during concurrent and cycling exercise (Δ−0.14 ± 0.33 ml·min−1·mmHg−1; Δ−0.14 ± 0.38 ml·min−1·mmHg−1, P<0.003). RHG increased MSNA burst frequency (Δ4 ± 8 burst/min, P=0.04) without altering burst amplitude (Δ7 ± 14 %, P=0.7) or total MSNA (Δ40 ± 40 %, P=0.07). In contrast, cycling and concurrent exercise had no effects on MSNA burst frequency (Δ−3 ± 6 burst/min and Δ4 ± 6 burst/min, P≥0.1) but increased burst amplitude (Δ34 ± 30 %; Δ31 ± 31 %, P≤0.001) and total MSNA (Δ59 ± 63 %; Δ94 ± 100 %, P≤0.007). In conclusion, during one‐leg cycling or concurrent exercise, reductions in inactive leg SFA vascular conductance occurred in parallel with increases in burst amplitude and total MSNA but not burst frequency. Exercise studies relying solely on measures of MSNA burst occurrence may not accurately reflect the corresponding changes in vascular conductance.

Support or Funding Information

Research was supported by a Natural Science and Engineering Research Council (NSERC) of Canada Discovery Grant (P.J.M; #06019), the Canada Foundation for Innovation (P.J.M.; #34379), and the Ontario Ministry of Research, Innovation, and Science (P.J.M. #34379).

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Vanin‐1 as a novel biomarker for kidney injury for hydronephrosis
Authors: Hosohata Keiko
Published: April 2020

Urinary tract obstruction and the subsequent development of hydronephrosis represent a common cause of kidney injury, resulting in chronic kidney disease. Neither currently used imaging techniques nor conventional laboratory parameters are sufficient to assess the onset of this condition. The purpose of the study was to assess whether vanin‐1 could be a novel renal biomarker in kidney injury due to hydronephrosis. Male Sprague‐Dawley rats were subjected to unilateral ureteric obstruction (UUO) or sham operation. For urinalysis, renal pelvic urine and voided urine were used for the UUO, and sham‐operated rats, respectively. Urinary vanin‐1 excretion was expressed as a vanin‐1/creatinine ratio. In addition to echographic images demonstrating time‐dependent accumulation of urine in the renal pelvis, histopathological renal tubular injuries became severe and renal fibrosis eventually developed. At day 7 after UUO, the vanin‐1 level in the renal pelvic urine was significantly higher than that in voided urine from the sham‐operated rats, and remained at the same level until day 14. Immunohistochemical staining of vanin‐1 in the renal cortices revealed that vanin‐1 expression was localized not only around the injured tubules, but also within a subset of injured tubules, but not in the area with interstitial fibrosis. Vanin‐1 mRNA and protein expression significantly decreased, whereas the expression of transforming growth factor (TGF)‐β1 and snail‐1, which plays a pivotal role in the pathogenesis of renal fibrosis via the epithelial‐to‐mesenchymal transition (EMT), increased. These results suggest that vanin‐1 in the renal pelvic urine is released from the renal tubular cells in UUO rats and reflects renal tubular injury at an early stage. Hydronephrosis always involves incomplete obstruction, and urinary vanin‐1 may serve as a candidate biomarker of renal tubular injury due to hydronephrosis.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Metabolism of Glycolate to Oxalate in Kidney Proximal Tubule Cells
Authors: Fargue Sonia
Published: April 2020

Background

Excessive synthesis of oxalate is a hallmark of the inherited kidney stones disease primary hyperoxaluria. Evidence indicates that the liver is the main site of oxalate synthesis but that other tissues may also contribute up to 20%. Glycolate is one of the precursors of oxalate and both plasma and urine glycolate are elevated alongside oxalate in primary hyperoxaluria type 1, the most frequent and severe of PH types. New therapeutic strategies in PH1 further increase glycolate levels by inhibiting a liver‐specific enzyme, hydroxyacid oxidase 1 (HAO1), which catalyzes the oxidation of glycolate to glyoxylate, a precursor of oxalate. To examine whether kidneys contribute to oxalate synthesis, the metabolism of glycolate was studied in human and mouse kidney cell lines and tissue.

Methods

Tissue culture cells derived from human proximal tubule (HK2 cells) and mouse collecting duct (mIMCD cells) lineages were incubated with 13C2‐labeled glycolate (0 – 10mM) for up to 24 hours. Kidney tissue incubations with 13C2‐glycolate were performed on mouse kidneys and human surgical kidney remnants, by isolating and digesting cortical and medullary tissue fragments. The amount of 13C2‐labeled oxalate synthesized by the cells (and released in the media) was measured by ion chromatography coupled with mass spectrometry and normalized to total cell protein.

Results

Metabolism of glycolate to oxalate was observed in proximal tubule cells (HK2) in as little a time as 3 hours and with concentrations as low as 500 uM in contrast to cells isolated from the medulla and collecting duct (mIMCD). The synthesis of oxalate was also observed in human and mouse kidney cortical tissue but not medullary tissue. The involvement of the intermediate metabolite glyoxylate was suggested by the higher oxalate synthesis observed in the glyoxylate reductase knock‐out mouse model of PH type 2.

Conclusion

Renal cells, in particular proximal tubule cells, are equipped to metabolize glycolate to glyoxylate and oxalate. The time and dose dependence of glycolate to oxalate metabolism is compatible with an enzymatic pathway. The role of the candidate enzyme hydroxyacid oxidase 2, an isoenzyme of HAO1 and which is expressed in the proximal tubule, is currently being investigated.

Support or Funding Information

NIH NIDDK K01DK114332

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Structural mechanism of vaccinia virus protein C6 mediated inactivation of transcription factors IRF3 and IRF7 via inhibition of TBK1 mediated scaffold protein‐protein interactions
Authors: Chakraborty Sayan , Xu Guozhou
Published: April 2020

Interferons (IFNs) are signaling proteins with potent antiviral and immune stimulatory effects. IFN signaling is initiated after host cell pattern recognition receptors (PRRs) recognize pathogen‐associated molecular patterns (PAMPs) present in many viral proteins. This event in turn generates a complex signaling cascade involving numerous proteins, activation of various transcription factors (TF), such as IFN‐regulatory factors (IRF) 3 and 7. These TFs subsequently translocate to the nucleus to elevate the transcription of type I IFNs, cytokines, and chemokines. Viruses such as Vaccinia virus (VACV) have evolved many strategies to interfere with the IFNs or their mechanism of action. Specifically, VACV encodes a small 16kDa protein, C6, that inhibits the activation of IRF3/7 via binding with an upstream kinase, TBK1, and its adaptor proteins TANK, NAP1, and SINTBAD in order to interfere with the production of IFNβ. Binding with these adaptor proteins, C6 prevents TBK1/IKKɛ‐dependent activation of IRF3 and IRF7 allowing VACV to evade immune recognition. To elucidate the structural mechanism of how C6 mediated inhibition of these adaptor protein/TBK1 interactions can block the activation of IRF3 and IRF7, we have chosen C6 and TANK as canonical binding partners. We have identified the binding regions between C6 and TANK by utilizing co‐expression/co‐purification studies of C6 and TANK proteins, and co‐crystallization trials are ongoing. The immune evasive strategy exploited by VACV can be used to develop novel therapies, such as C6 mimetics to provide TBK1 inhibition. The development of therapeutics depends immensely on a detailed structural analysis of the interactions between C6 and adaptor proteins. Our structural studies of C6 and TBK1 adaptor proteins will provide useful insights in developing superior therapies against malignancies, infectious diseases, and autoimmune disorders.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.