bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abrogation of Ozone‐induced Oxidative Stress, Inflammation, and Aberrant Pulmonary Mechanics by Valproic Acid
Authors: Lee Jordan , Sunil Vasanthi R. , Vayas Kinal , Abramova Elena , Cervelli Jessica , Laskin Jeffrey D. , Laskin Debra L. 
Published: April 2020

Acute exposure to inhaled ozone causes oxidative stress, inflammation, and impaired pulmonary mechanics. This is associated with an accumulation of inflammatory macrophages in the lung that contribute to toxicity by releasing reactive intermediates and pro‐inflammatory mediators. In the present studies we assessed the effects of valproic acid (VPA), a histone deacetylase inhibitor with antioxidant and anti‐inflammatory activity, on ozone‐induced pulmonary toxicity. Female C57B16/J mice (18–22 g) were exposed to air or ozone (0.8 ppm, 3 h) in whole body chambers. This was followed 30 min and 24 h later by i.p. administration of PBS control or VPA (300 mg/kg). Mice were euthanized 48 h later and bronchoalveolar lavage (BAL) and tissue collected. Ozone‐exposure resulted in increased levels of protein, IgM and cells in BAL, indicative of lung injury and inflammation. Ozone also caused oxidative stress as measured by increases in lung hemeoxygenase (HO)‐1 and 4‐hydroxynonenal (4HNE) modified proteins. Treatment of mice with VPA significantly reduced ozone‐induced increases in expression of HO‐1 and 4HNE modified proteins. Flow cytometric analysis of BAL lung cells showed that ozone‐induced injury and oxidative stress were associated with increases in pro‐inflammatory macrophages in the lung. These cells expressed ARL11 and TNFα, demonstrating that they are activated. VPA treatment reduced the number of activated macrophages accumulating in the lung in response to ozone; VPA also suppressed the accumulation of monocytic and granulocytic myeloid‐derived suppressor cells (MDSC). Ozone‐exposure caused alterations in pulmonary function, including increases in resistance and decreases in tissue elastance; these changes were blunted by VPA. Taken together, our data demonstrate that VPA is effective in reducing ozone‐induced inflammation, oxidative stress, and mechanical dysfunction. These findings may be useful in the development of therapeutics to treat oxidant induced lung injury.Support or Funding InformationSupported by Rutgers SURF/ASPET, NIH ES004738, AR055073, and ES005022.
Effects of Different Cerium Oxide Nanoparticle Formulations on Oxidative Stress Survival in the Nematode C. elegans
Authors: Farber-Krug Acacia E. , Estevez Ana Yesenia 
Published: April 2020

Cerium oxide (CeO2) nanoparticles (CeNPs or nanoceria) are potent antioxidants that are being explored as a potential therapeutic for diseases in which oxidative stress plays an important pathological role. Nanoceria catalytically neutralize multiple types of reactive oxygen species. However, both therapeutic and toxic effects of CeNPs have been reported. We hypothesize that these disparate reports are due to small differences in each type of nanoparticle arising from the synthetic process. These small differences could lead to particles that aggregate and induce toxicity versus particles that are monodispersed and display antioxidant properties. Due to its short lifespan and easily observable behaviors, we used the nematode worm C. elegans to examine, in parallel, the effects of three different types of cerium oxide nanoparticle formulations on survival after exposure to oxidative stress. To induce oxidative stress, we used juglone (5‐hydroxy‐1,4‐naphthoquinone), a compound derived from many plant species including the black walnut tree, Juglans nigra. We first conducted a dose‐response analysis to find a concentration of juglone that induced significant mortality in our model system. This dose of juglone, 250 μM, was then used in subsequent experiments to test the impact of nanoparticle pre‐treatment on worm viability. For these studies, animals were fed, starting at the L1 larval stage, a range of doses (0 to 580 μM) of three formulations of nanoceria that differed in size as well as the stabilizers used during synthesis. When the worms reached young adulthood, they were exposed to 250 μM juglone for 1 hour. Worms were then placed back onto fresh growth plates containing nanoceria and animal viability was determined 24 hr later via a nose‐touch assay conducted by an experimenter blind to treatment. Preliminary analysis shows that the three different formulations tested showed varying potency in protecting C. elegans from juglone‐induced oxidative stress, supporting our hypothesis that differences in synthetic parameters can impact the ultimate biological effect of the nanoparticles.Support or Funding InformationFunding provided by St. Lawrence University.
Methcathinone Rapidly Decreases Dopamine Transporter Function: Role of Calcium and Protein Kinase C
Authors: Magee Charlotte P. , Siripathane Yasmeen H. , Le BaoMinh D. , Hanson Glen R. , Fleckenstein Annette E. 
Published: April 2020

Methcathinone (MCAT) is a synthetic cathinone that causes both persistent striatal dopaminergic as well as striatal and hippocampal serotonergic deficits. It has been demonstrated that the rapid effects of similar stimulants on dopamine (DA) transporter (DAT) function contribute to persistent monoaminergic deficits. Thus, the effect of MCAT on DAT was assessed. Results revealed that MCAT self‐administration (SA) decreased striatal [3H]DA uptake, as assessed ex vivo in synaptosomes prepared from male rats 1 h after the final MCAT SA session. In vitro co‐incubation of synaptosomes with MCAT (1, 10, 100 μM) at 37°C likewise decreased striatal [3H]DA uptake. There was no effect of in vitro co‐incubation with MCAT at 4°C, suggesting that decreases in [3H]DA uptake are not due to residual drug. These effects were not limited to DAT as MCAT SA decreased hippocampal [3H]serotonin uptake. Further, in vitro co‐incubation of synaptosomes with MCAT decreased both striatal and hippocampal [3H]serotonin uptake. The in vitro effect on DAT function was attenuated by co‐incubation with the cell‐permeable calcium chelator, 1,2‐bis (2‐aminophenoxy) ethane‐N, N, N, N‐tetraacetic acid acetoxymethyl ester (BAPTA‐AM), as well as with the structurally related non‐specific protein kinase C (PKC) inhibitors bisindolylmaleimide I and Ro‐31‐7549. In contrast, this in vitro decrease in DAT function was not attenuated by co‐incubation with other non‐specific PKC inhibitors (NPC‐15437 and Go6976), nor with the PKC‐β inhibitor ruboxistaurin. Neither co‐incubation with the Ca2+/calmodulin‐dependent protein kinase II inhibitor, KN‐93, nor the glycogen synthase kinase 3β inhibitor, SB‐216763, attenuated the MCAT‐induced decrease in [3H]DA uptake. Taken together, these results suggest that MCAT self‐administration and in vitro MCAT exposure have comparable effects to investigator administered MCAT on DAT and SERT function in the striatum and hippocampus; further, in vitro data suggest that the MCAT‐induced effect on DAT is dependent upon calcium and some, but not all, PKC isoforms.Support or Funding InformationR01‐DA039145
RAGE and phospho‐ATM correlation during DNA Double Strand Breaks in trophoblast cells
Authors: Tsai K.Y.F. , Hirschi-Budge K. M. , Davis T. , Llavina S. , Tullis B. , Jones N. , Fowers R. , Graff T. , Reynolds Paul R. , Arroyo J. 
Published: April 2020

Trophoblasts are critical for successful pregnancies and they mediate important steps including implantation, immune protection of the fetus, maternal blood flow to the placenta, and delivery. Increased DNA double strand breaks (DNA‐DSBs) in trophoblasts has been implicated in complicated pregnancies such as intrauterine growth restriction. Previous studies in our laboratory showed increased expression of the receptor for advanced glycation end‐products (RAGE) following cigarette smoke extract (CSE) treatment of trophoblast cells. More recently, a role for nuclear RAGE (nRAGE) has been implicated in DNA‐DSB repair in these cells. ATM is a regulator known to be involved in the repair of DNA‐DSBs through interaction with molecules associated with DNA repair. We tested the hypothesis that RAGE associates with ATM in facilitating DNA‐DSB repair in trophoblast cells. DSBs were induced in human trophoblasts by exposure to cigarette smoke extract (CSE) or bleomycin (BLM). Assessment of nRAGE and g‐H2AX (involved in DNA‐DSB repair) was done by immunoblotting. Immunoprecipitation was used to quantify RAGE and p‐ATM complexing in cells. Invasion was measured after CSE and BLM treatment in the presence or absence of a RAGE neutralizing antibody (nAb).Increased expression of RAGE and g‐H2AX was detected (1.4‐fold and 1.6‐fold; p<0.05) in treated trophoblast cells compared to controls. Trophoblast invasion was decreased by 65% with BLM treatment compared to controls (p<0.0005) and diminished invasion was further enhanced (73%, p<0.0004) when RAGE nAb was added. Similarly, trophoblast invasion was decreased by 58% (p<0.002) when treated with 1% CSE and further decreased (79%, p<0.0006) in the presence of RAGE nAb. There was also a significant increase (56%, p<0.002) in RAGE expression when p‐ATM was immunoprecipitated from trophoblasts treated with CSE.We conclude that CSE and BLM cause DNA‐DSBs in trophoblast cells and that DNA‐DSB repair may plausibly involve nRAGE association with ATM. We further conclude that DNA‐DSBs could be a factor that inhibits trophoblast invasion. Nuclear RAGE may be a potential target that maintains trophoblastic invasion by assisting in the repair of DNA‐DSBs. These studies provide a critical insight into dissecting tobacco‐mediated placental deficiency.Support or Funding InformationThis work was supported by a grant from the Flight Attendant’s Medical Research Institute (FAMRI, PRR and JAA) and a BYU Mentoring Environment Grant (JAA and PRR).
Regulation of GPCR activation of the Hippo pathway in metastatic breast cancer
Authors: Arakaki Aleena K. S. , Pan Wen-An , Trejo JoAnn 
Published: April 2020

G protein‐coupled receptors (GPCRs) regulate the Hippo signaling pathway, a developmental pathway involved in tumorigenesis and metastasis. Although GPCRs promote cancer progression and are highly druggable, there are currently no FDA‐approved drugs targeting GPCRs for cancer treatment. Protease‐activated receptor‐1 (PAR1) is a GPCR that both activates the Hippo pathway and promotes breast cancer progression. PAR1 is overexpressed in breast cancer patient tumor biopsies and in invasive breast carcinoma cell lines, and correlates with increased metastasis and poor prognosis. We found that PAR1 overexpression is due to defective lysosomal trafficking and results in persistent signaling observed in multiple triple‐negative breast carcinoma cell lines including the model invasive MDA‐MB‐231 cells. We recently showed that the α‐arrestin domain containing protein‐3 (ARRDC3), a tumor suppressor, is reduced or lost in highly aggressive triple‐negative breast carcinoma and this is responsible for aberrant PAR1 lysosomal trafficking and persistent signaling, leading to increased invasion. However, the link between ARRDC3 expression and PAR1‐stimulated Hippo pathway regulation in invasive breast cancer is not known and was examined. Here, we show that ARRDC3 regulates GPCR activation of the Hippo pathway in triple‐negative breast cancer, where the transcriptional co‐activators YAP and TAZ display distinct functions. ARRDC3 re‐expression in invasive breast carcinoma cells attenuates GPCR‐stimulated Hippo signaling and invasion that is mediated by activation of TAZ but not YAP. Furthermore, siRNA‐targeted depletion of TAZ, but not YAP inhibits GPCR‐induced Hippo signaling and invasion. An understanding of the mechanisms by which the Hippo pathway is regulated by GPCRs may lead to new potential therapeutic targets for the treatment or prevention of metastatic breast cancer.Support or Funding InformationFunding for this project was provided by the HHMI Gilliam Fellowship for Advanced Study, the UCSD Graduate Training Program in Cellular and Molecular Pharmacology through NIH General Medical Sciences, T32 GM007752 and the UCSD Tribal Membership Initiative (Aleena Arakaki) and by the National Institute of Health NIGMS R01 GM090689 and R35 GM127121 (JoAnn Trejo).
IH‐dependent HIF1a signaling upregulates reactive oxygen species signaling to suppress expression of the hippocampal NMDA receptor by downregulating the NR1 subunit.
Authors: Arias-Cavieres Alejandra , Nwakudu Chin , Fonteh Ateh , Garcia Alfredo J. 
Published: April 2020

When left untreated, the periodic cessation in breathing occurring with sleep apnea can cause oscillations in blood oxygenation leading to intermittent hypoxia (IH) and disrupted cognitive function. IH causes oxidative stress in the nervous system and impair spatial learning and memory. This study examines how IH influences synaptic physiology of principal neurons in the hippocampus. We hypothesize that IH‐dependent HIF1a signaling remodels the glutamatergic synapse by upregulating reactive oxygen species (ROS), weakening N‐methyl‐D‐aspartate receptor (NMDAR)‐dependent long‐term potentiation (LTP), and impairing cognitive performance on hippocampal based behavior. Wildtype mice (WT) and mice hemizygous for HIF1a (HIF1a+/−) were exposed to ten days of IH. While spatial memory in the Barnes maze was impaired in WT following IH (n=6), performance in the Barnes maze was unaffected by IH among HIF1a+/− (n=6). Electrophysiological recordings in brain slices from WT (n=6) and HIF1a+/−(n=6) exposed to IH also revealed that NMDAR‐dependent LTP was suppressed only in WT slices. While IH caused a down regulation of the NR1 subunit from WT, protein carbonylation and HIF1a regulated oxidase, NOX4, was increased by IH in the WT exposed to IH. No changes in NR1, protein carbonylation, or NOX4 were observed in HIF1a+/− exposed to IH. Furthermore, the administration of the superoxide anion scavenger MnTMPyP (5 mg/Kg i.p) during IH mitigated the downregulation of NR1 and suppression of NMDAR‐dependent LTP in WT. These results show that IH‐dependent HIF1a signaling causes targeted disruption to NMDAR‐dependent LTP through a ROS‐based mechanism that involves the downregulation of NR1 subunit. We provide new insight into the mechanistic basis by which sleep apnea may disrupt cognitive performance.Support or Funding InformationSupported by NIH Grant R01‐NS‐1074210100
Tailoring HDL mimetics for in vivo delivery of mRNA
Authors: He Wei , Rasley Amy , Gilmore Sean F. , Peters Sandra , Coleman Matthew A. , Fischer Nicholas O. 
Published: April 2020

In vivo delivery of nucleic acid‐based therapeutics utilizing messenger RNA (mRNA) has significant implications for gene therapy, counteragent delivery, and vaccine applications. The mRNA therapeutics harness the body’s own cells to produce and deliver therapeutic protein molecules. However, large RNA molecules are prone to RNase degradation and exhibit marked difficulty in in vivo delivery compared with smaller RNA molecules. We have successfully engineered reconstituted high‐density lipoproteins (termed nanolipoprotein particles, NLPs) to deliver self‐amplifying mRNA (aka. Replicon) constructs in vivo. NLPs are nanometer‐scale, discoidal particles. They are safe, non‐immunogenic, and amenable to multiple routes of delivery. Also, the size and surface chemistry of NLPs allow for facile optimization of the delivery of compounds with wide range of physicochemical properties. To tailor NLPs for in vivo delivery of large nucleic acids molecules, a panel of NLPs formulated with a wide range of cationic lipids and assembly constituents were screened. Cationic lipids confer NLPs positive charge which successfully complexed with RNA Replicons encoding luciferase, provided protection from RNase degradation, and enhanced mRNA in vivo expression efficiency. These results represent the experimental foundation of utilizing the NLP technology to advance for RNA delivery. Future efforts focus on elucidating the correlation of NLP composition, NLP‐Replicon structure, and in vivo efficacy that will eventually allow for the rational design of a highly potent in vivo delivery platform that can be used as a universal mRNA delivery technology.Support or Funding InformationThis work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE‐AC52‐07NA27344, through LDRD award 20‐ERD‐004. This work was also supported by U19 AI144184 from the National Institute of Allergy and Infectious Diseases
NAD Redox Imbalance Drives Diabetic Cardiomyopathy: Roles of oxidative stress and post‐translational modifications
Authors: Lee Chi Fung 
Published: April 2020

Diabetes is a major risk factor of heart failure. Diabetes and heart failure both have been linked to NAD redox imbalance. However, the causal role of NAD redox state in the progression of diabetic cardiomyopathy (DC) has not been directly tested. We induced diabetes in wild type mice (WT) by streptozotocin (STZ) injections. Chronic diabetic stress to WT mice (16 weeks) led to gradual declines in cardiac function and lowered NAD/NADH ratio, suggesting the association of NAD redox imbalance in linking diabetic stress with cardiac dysfunction. To determine the causal role of NAD redox imbalance to drive DC, we used cardiac‐specific Ndufs4‐KO mice (cKO), which exhibit lowered cardiac NAD/NADH ratio without overt dysfunction. While insulin depletion and hyperglycemia were similar in diabetic control and cKO mice, cardiac dysfunctions were exacerbated in diabetic cKO mice. Cardiac fibrosis levels of diabetic control and cKO hearts were measured by trichrome staining. Although cardiac fibrosis was slightly elevated in diabetic hearts compared to non‐diabetic controls, but there was no difference between diabetic control and diabetic cKO hearts. Similar in vivo and histological observations were made in both diabetic male and female cohorts. The results suggest that the accelerated decline of cardiac function associated with the pre‐existed NAD redox imbalance is not be due to enhanced fibrosis and is independent of sex. We next analyzed acetylation‐dependent pathways to account for the accelerated decline of function in diabetic cKO hearts. NAD redox imbalance in diabetic cKO hearts promoted protein acetylation, including SOD2 acetylation (SOD2‐K68Ac). SOD2 acetylation inhibits its antioxidant function. We observed elevated protein oxidation levels in diabetic cKO hearts, while expression of genes regulating oxidative stress (Nox1, 2, 4) remained unchanged. The results suggest that NAD redox imbalance promotes oxidative stress by suppressing antioxidant pathway via protein acetylation. To gain further insights how NAD redox imbalance may regulate cardiomyocyte function, phosphorylation levels of myosin binding protein C (MyBPC) and troponin I (TnI) were examined. In diabetic cKO hearts, TnI phosphorylation was increased while MyBPC phosphorylation remained unchanged, suggesting that hyperacetylation in cKO hearts regulates cardiomyocyte contraction‐relaxation to promote cardiac dysfunction. To normalize NAD redox imbalance, we elevated NAD levels in diabetic cKO mice with cardiac‐specific NAMPT overexpression. NAMPT is the rate‐limiting enzyme in salvage pathway. Cardiac NAMPT expression slowed the accelerated decline of cardiac function in diabetic cKO hearts. Our findings collectively suggested that NAD redox imbalance drives DC and the NAD‐dependent pathways regulating DC progression warrant further investigations.Support or Funding Information1. Scientist Development Grant (17SDG33330003), American Heart Association;2. Seed Funding, Presbyterian Health Foundation of Oklahoma City
Acute Voluntary Wheel Running Attenuates Olanzapine‐Induced Hyperglycemia in Male Mice
Authors: Ashworth Kristen E. , Shamshoum Hesham , Medak Kyle D. , Wright David C. 
Published: April 2020

BackgroundOlanzapine is a second‐generation antipsychotic often used in the treatment of schizophrenia and other “off‐label” conditions. Though effective in reducing psychoses, the use of olanzapine is associated with adverse metabolic side effects. Acutely, olanzapine increases liver glucose output and the development of insulin resistance. Chronic olanzapine treatment leads to weight gain and predisposes individuals to the development of cardiovascular disease and type 2 diabetes. Exercise is an intervention which helps to maintain glucose homeostasis, and with long‐term adherence, can decrease glucose intolerance and insulin resistance. We have previously demonstrated that a single bout of exhaustive exercise mitigates olanzapine‐induced hyperglycemia. While these findings are encouraging, the clinical relevance of exhaustive exercise in individuals taking olanzapine is limited.Purpose & HypothesesThe purpose of this study was to investigate if increases in short‐term, habitual physical activity in the form of voluntary wheel running (VWR) would have a protective effect against olanzapine‐induced hyperglycemia.Methods10‐week old male C57BL/6J mice remained sedentary or were provided running wheels at the start of the dark cycle (~20:00 h), until the following morning (~8:00 h; start of light cycle). Olanzapine (5 mg/kg body weight (BW)) was administered intraperitoneally (IP) immediately following overnight VWR, or 6 hours and 24 hours post wheel‐lock. Blood glucose was measured at baseline, 30, 60, 90, and 120 mins post‐olanzapine. In parallel experiments following the same overnight VWR protocol, an insulin tolerance test (ITT) (0.5 IU/kg BW; IP) was conducted 60 mins post‐olanzapine treatment to assess olanzapine‐induced insulin resistance among groups.ResultsA single overnight session of VWR protected against acute olanzapine‐induced hyperglycemia immediately post‐wheel lock. This protective effect was still present 6 hours post‐wheel lock, and had reversed by 24 hours after the cessation of exercise. Under insulin‐stimulated conditions, the sedentary olanzapine‐treated mice had significantly higher blood glucose area‐under‐the‐curve compared to the other three groups, providing evidence that a prior bout of VWR protects against olanzapine‐induced insulin resistance. Under insulin‐stimulated conditions, serum free fatty acid concentrations were increased with olanzapine and reduced with VWR.ConclusionsOur findings demonstrate that with a single session of overnight habitual physical activity, olanzapine‐induced hyperglycemia is mitigated for at least 6 hours post‐exercise and insulin‐stimulated glucose disposal is recovered under olanzapine‐treated conditions.Support or Funding InformationThis study was supported by the Canadian Institutes of Health Research.