bluuebunny/crossref_metadata_2025 huggingface dataset:
Mentorship for developing course‐based undergraduate research experiences (CUREs): The Council on Undergraduate Research (CUR) Mentorship for Integrating Research Into the Classroom (MIRIC) program
Authors: Wolyniak Michael J. , Resendes Karen K.
Published: June 2021

The life science education community has responded to the recommendations of the American Association for the Advancement of Science (AAAS) Vision and Change document with several initiatives designed to improve the way in which undergraduates learn science. These initiatives have often taken the form of one‐time workshops that generate awareness of and interest in developing authentic research experiences for undergraduate STEM classrooms. However, they have been less successful with respect to generating the sustainable change necessary to bring real reform to undergraduate science education. To create sustainable change, long‐term faculty development initiatives focused on mentorship are needed so that instructors seasoned in developing and implementing course‐based undergraduate research experiences (CUREs) can convey their experiences to mentees interested in using these pedagogical techniques as the centerpiece of their own teaching. The Council on Undergraduate Research (CUR) Biology Division and American Society for Cell Biology (ASCB) Education Committee are creating the Mentorship for Integrating Research Into the Classroom (MIRIC) program to provide a means for members with an interest in developing improved and sustainable active learning techniques to gain experience in this style of teaching through close, long‐term interaction with a veteran teaching mentor.

Developed from the former ASCB Mentorship in Active Learning and Teaching (MALT) program, MIRIC focuses on the development of instructors who wish to develop a dynamic CURE. Current and future life science instructors pair themselves up with seasoned veterans of CURE development and work with them and their students over the course of a semester or longer to develop a CURE that will allow the mentee to bring authentic research into his or her classes.

In our pilot studies, we collected qualitative and quantitative data based on participant interviews and coding videos of student and instructor actions during classroom activity (Smith et al., 2013), respectively, that suggest that MIRIC/MALT mentorships have made positive gains in promoting sustainable active learning techniques among participants. Going forward, we wish to use instruments like the Laboratory Course Assessment Survey (Corwin et al., 2015) and Experimental Design Ability Test (Sirum and Humburg 2011) to assess the effectiveness of the MIRIC laboratory intervention.

MIRIC will undergo its full launch in 2018. At present, please consult http://www.ascb.org/mentoring‐in‐active‐learning‐and‐teaching‐malt/ for more information on becoming involved.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Graduate student professional development and a CURE‐style course and peer‐reviewed student publications
Authors: Baumgartner Jackson , Lee Jesi , Kuhn Misty L.
Published: June 2021

Implementing Classroom Undergraduate Research‐based Experiences (CUREs) into an institution's curriculum has shown measurable benefits for students in the chemical sciences. However, several areas in biochemistry, such as protein structure, have shown resistance to a similar scale of implementation. Here, we describe a graduate level CURE‐style pilot program on protein structure/function that was held at San Francisco State University. In this class, first and second year Master's students investigated four individual crystal structures of proteins of the dTDP‐L‐rhamnose biosynthetic pathway. The students examined the biochemical and structural background literature of their assigned proteins, visualized and analyzed protein 3D structures using in silico methods, and wrote a manuscript for submission for publication. A weekly “show‐and‐tell” was held during each session where the students shared their findings and expertise with classmates. Students worked individually and in groups, which mimicked the free exchange of ideas and feedback typical of a scientific community's communication process. We chose structures of each protein that belonged to a single metabolic pathway to ensure multiple types of protein structures were observed, analyzed, and discussed during the course. Additionally, it provided a cohesive biological context for discussion and understanding of how proteins within a metabolic pathway coordinate to complete a cellular process. A manuscript‐style final paper and poster presentation at the University's annual research poster showcase were the primary classroom assessments for the course. One caveat of this approach regarding publication of results is that the instructor must be able to collaborate with the original structure depositor. Overall, this CURE‐like graduate course provided Master's students with a unique opportunity to experience the authentic preparation of a research publication, which is indispensable for preparing them for their future scientific careers. Three of the four manuscripts that were submitted for publication are currently in press.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mutation in MON2, Which Encodes a Protein Implicated in Vesicular Transport, Affects Response to Exogenous Fatty Acids in Yeast
Authors: Draper Riley , Gasparotto Anthony , Soni Mona , Gasper Brittany , Stukey Joseph , McDonough Virginia
Published: June 2021

Metabolism of exogenous fatty acids requires cells to take up, traffic, and molecularly respond to fed fatty acids. Our lab has determined that a mutation in mon2 results in defective growth on the fatty acid 10‐undecenoic acid. Like wild type cells, mon2Δ mutants are capable of normal response to the feeding of long chain unsaturated fatty acids (UFAs) by reducing transcription of OLE1, (which encodes the Δ9 desaturase), and by reducing the accumulation of endogenously produced UFAs. However, wild type cells when fed 10‐undecenoic acid will continue to express OLE1 and increase their content of endogenously produced UFAs. In contrast, mon2Δ mutants do not differentially respond to the two fatty acids. Staining with a BODIPY‐labeled fluorescent fatty acid analog indicates that there is a difference in localization/amount of the supplied fatty acid in mon2Δ cells compared to wild type cells. Thus, it appears that the mon2 mutation decreases the cell's ability to differentiate between fatty acids, perhaps due to mislocalization of the fed fatty acid or regulatory proteins.

Support or Funding Information

This work was supported by a Jacob Nyenhuis Faculty Award (VM), NSF‐REU (AG, MS, BG) and a Summer Scholar award from the Dean for Natural and Applied Science (RD).

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Human Follicle Stimulating Hormone Receptor Lipid Raft Residency is Hormone and Caveolin Dependent
Authors: Madden Hannah E. , Stewart Angelina , Cohen Brian D.
Published: June 2021

Human follicle stimulating hormone (hFSH) is a gonadotropin responsible for the maturation of ovarian follicles in women and production of sperm in men. The receptor (hFSHR) is a G protein‐coupled receptor (GPCR); a class of receptors found embedded in the cell membrane to receive the hormone resulting in initiation of a complex downstream signaling cascade. Through previous research in the Cohen lab, hFSHR has been shown to be located within compartments of the cell membrane known as lipid rafts. Lipid rafts are microdomains of the membrane containing a higher concentration of cholesterol, glycosphingolipids, and a protein known as caveolin. Current research is focused on evaluating the mechanisms and effects of hFSHR lipid raft residency. Using discontinuous sucrose gradients we have shown that hFSH stimulation of an HEK293 cell line stably transfected with hFSHR cDNA results in alteration of hFSHR lipid raft residency in a time dependent manner.

To better understand the mechanism and effect of hFSHR lipid raft residency the same cells were treated with a peptide mimetic of transmembrane domain 4 of hFSHR. This peptide includes a sequence consistent with a motif shown in other proteins to interact with caveolin (ϕXϕXXXXϕXXϕ where ϕ is an aromatic amino acid). The putative caveolin interaction motif of hFSHR was synthesized along with the HIV‐TAT leader sequence to allow passage through the membrane. A second peptide where the aromatic amino acids were replaced with leucine was also used. Cells treated with the wild type peptide showed elevated basal signaling in the absence of hFSH, an effect not observed with the mutant peptide.

Together, these results suggest that hFSHR residency in lipid rafts is dependent on hormone treatment and interaction with caveolin. Through studying hFSHR lipid raft residency and signaling we hope to identify ways to control the receptor for improved methods for contraception and treatment of infertility.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Isolation of Phagosomes Containing Bovine Photoreceptor Outer Segments from Retinal Pigment Epithelial Cells by Magnetic Selection
Authors: Dorvilier Rachelle , Shelby Shameka
Published: June 2021

Daily phagocytosis of the distal tips of photoreceptor cells by the retinal pigment epithelium (RPE) is known to be an essential mechanism in the maintenance of the retina. The outermost portions of the photoreceptor cells, termed outer segments, are ingested and subsequently processed by the RPE. Previous studies involving the isolation of phagosomes have utilized latex beads to induce phagocytosis in macrophages, which lacks specificity due to the large foreign body being ingested. Therefore, the purpose of this study was to develop a standard protocol for the isolation of outer segment enriched phagosomes from RPE cells. To generate phagosomes with the selected cargo, outer segments isolated from bovine retinas were covalently labelled with magnetite particles and then fed to RPE‐J cells. After feeding, the cells were washed and gently lysed with a Dounce homogenizer. The phagosomes containing the magnetite bound outer segments were collected via magnetic rack isolation and stored in a homogenization solution. Immunoblots using antibodies against Mertk, N and C‐terminal rhodopsin, and cathepsin D confirmed the presence of outer segment‐containing phagosomes of varying maturity in the isolated fraction. The protocol we have developed has successfully isolated outer segment enriched phagosomes from RPE‐J cells by magnetic selection. This study differentiates itself from other studies that employ latex beads to isolate phagosomes through density gradient centrifugation. The isolation of these phagosomes will potentially play an important role in investigating protein interactions that impact RPE membrane trafficking and maturation.

Support or Funding Information

Florida Southern College Faculty‐Student Collaborative Research Grant

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of the Cell Cycle on Vacuole Size in S. cerevisiae yeast
Authors: Sims Jasmine C.
Published: June 2021

Malfunctions in a cell's ability to degrade unnecessary chemicals or proteins may lead to one of fifty distinctive lysosomal storage disorders in humans. Lysosomal storage diseases such as Tay‐Sach's, Salla, or Sialic Acid Storage diseases often lead to premature death in infants. Lysosomes are vital for degrading subcellular proteins no longer needed by the cell. Our research uses a functional homologue of lysosomes, the vacuole in S. cerevisiae yeast as a model system, which also functions in protein degradation.

We study vacuoles in S. cerevisiae yeast to understand protein degradation. We investigate whether changes in vacuole size and degradative function are influenced by the progression of the cell cycle. We hypothesize that changes in vacuolar size and specific phases of the cell cycle play an important role in degradative function. To address this, we designed experiments to approach this by linking vacuole size changes to the progression of the cell cycle. We halted the cells at each cell cycle stage to track vacuolar changes as the cell cycle progresses. We did this by incubating the cells with 4 cell cycle inhibition drugs: Tributyltin (G1 phase), Hydroxyurea (S phase), Epothilone B (G2 phase), and Nocodazole (M phase). Vacuoles were fluorescently labelled with VPH1‐GFP, a vacuolar surface protein. We imaged the samples using Spinning Disk Confocal Microscopy. We then analyzed the images with ImageJ and MatLab algorithms to track, compare, and characterize vacuolar change. Thus far, we have found that the vacuoles change in terms of copy number (the number of vacuolar lobes) as the cell cycle progresses. This preliminary evidence suggests that there is a correlation between changes in vacuolar size along with the progression of the cell cycle. Because of this, we hypothesize that vacuole size is influenced by the progression of the cell cycle.

In addition, decreases in degradative ability are correlated with enlarged vacuolar phenotypes, hence a logical future direction would be to test whether degradative ability may also be synchronized with the progression of the cell cycle. Characterizing these changes would allow us to predict degradative efficiency based on the phase of the cell cycle. Further research could determine whether protein degradation and vacuolar morphology depend on one another. Overall, our research is significant because it will provide molecular insight on how vacuolar morphology and degradation are regulated, which may lead to new treatments to help those who suffer from lethal lysosomal storage disorders, and those who struggle with inefficiencies in degradative ability.

Support or Funding Information

NSF‐Center for Cellular Construction Grant

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
GlycoSense™: A Rapid Method for Monitoring In Vitro Glycoengineering
Authors: Yang Loretta , Saunders Matthew J. , Samli Kausar N. , Woods Robert J.
Published: June 2021

The use of enzymes to modify glycans, in order to generate uniform protein glycosylation for optimal bioactivity, or to test glycan‐structure function hypotheses, or in chemo‐enzymatic synthesis, has emerged as a transformative technology. However, there are no convenient cost‐effective methods for monitoring the progress of the enzyme reactions during in vitro glycoengineering.

Lectenz® Bio has developed an innovative technology called GlycoSense™ that will permit in vitro glycoenzyme reactions to be monitored in near real‐time using flow cytometry and multiplex microspheres (beads). The GlycoSense™ method detects binding between glycans and glycan‐specific reagents that are conjugated to spectrally‐unique beads. By combining the individual bead‐based reagents into a multiplexed array, a profile of key glycan features can be obtained in less than a minute on a basic cytometer.

We illustrate the performance of the GlycoSense™ method using glycans and glycoprotein standards, and demonstrate its utility by monitoring changes in glycosylation patterns upon treatment with glycoenzymes. The GlycoSense™ approach will address the unmet need for a rapid tool to monitor protein glycosylation during in vitro glycoengineering.

Support or Funding Information

National Institutes of Health (U01CA221213, R43GM123863)

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Neuroregeneration improved by ketones
Authors: D'Agostino Csilla Ari , Zippert Monique , D'Agostino Dominic P.
Published: June 2021

Ketone bodies serve as alternative fuel for the brain when glucose availability is limited. The ketone body beta‐hydroxybutyrate (BHB) is synthesized in the liver from acetoacetate, the first ketone produced in the fasting state. Several studies show that being in the state of ketosis can be neuroprotective, but the exact mechanism is not known. It is also not known whether ketones would aid regeneration of a nervous system injury. In this study we investigated on cell cultures whether ketone bodies improve neuroregeneration after injury or trauma.

The effect of ketone bodies on cell regeneration was tested in 3 weeks old rat (Sprague Dawley) primary neuronal cell cultures. Scratch assay was performed for 24 hours, while the cells were either exposed to 2mM R, S‐sodium‐3‐hydroxibutyrate (BHB) or not (control). One hundred snapshots were taken with the CYTOSMART system to document the cell migration, changes in cell density and the process of cell regeneration into the damaged area over the 24 hours. Immunofluorescence reaction was performed to label beta III tubulin and synapsin I in the regenerating areas.

Cell cultures treated with BHB showed more intense cell migration and regeneration of the damaged area over the 24 hour period. Significantly more DAPI stained cell nuclei were found in the damaged area in cell cultures with 2mM BHB at 20× (p=0.01)and at 10× (p=0.0004) magnification photos as well, and the cell coverage was higher than in control cell cultures. Markers that are associated with flagellar movement, cytoskeletal functions and axonogenesis, synaptogenesis were denser in treated neuronal cultures at the regeneration site as revealed by fluorescence microscopy. These above results show potential applications for ketogenic compounds for treating traumatic brain injury or other injury to the central nervous system.

Support or Funding Information

University of South Florida Foundation

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
AKR1A1 deficiency is associated with high risk of alcohol‐induced fatty liver syndrome
Authors: Chen Wan‐Ru , Lan Ying‐Wei , Chen Hsiao‐Ling , Chen Chuan‐Mu
Published: June 2021

Alcoholic liver disease(ALD) is caused by excessive alcohol consumption. The spectrum of alcohol‐related liver injury varies from hepatic steatosis, steatohepatitis, alcoholic fibrosis to irreversible cirrhosis. AKR1A1 is a member of the aldo‐keto reductase (AKR) superfamily, which catalyze the reduction of various aldehydes to their corresponding alcohols in an NADPH‐dependent manner. The enzyme is encoded by the AKR1A1 gene that protects cells against oxidative stress and detoxification. The aim of this study is to identify the role of AKR1A1 deficiency in mouse hepatic diseases after chronic alcohol exposure. In this study, we have established a novel strain of AKR1A1 knockout (KO) mice, which integrated the pCAG‐eGFP transgene and simultaneously deleted 17kb of the AKR1A1 gene locus. The AKR1A1 KO mice (AKR1A1eGFP/eGFP) reduced ascorbic acid biosynthesis, may affect aldehyde reductase metabolism. Male AKR1A1eGFP/eGFP and CD‐1 control mice were divided into four groups(n=6) that fed either the Lieber‐Decarli diet containing 5 % ethanol (Ethanol‐fed) or an isocaloric (Pair‐fed) control diet for 8 weeks. In comparison with ethanol exposure‐CD‐1 control mice, the ethanol exposure‐ AKR1A1eGFP/eGFP mice showed a significant increase in the serum alanine aminotransferase (ALT) and aspartate transaminase (AST) levels (p<0.05), and the levels of pro‐inflammatory cytokines (TNF‐α and IL‐1β), hepatic triglycerides(TG) and cytochrome P4502E1(CYP2E1) were also elevated. However, the levels of antioxidant enzymes, including hepatic glutathione(GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) were significantly reduced in the ethanol exposure‐AKR1A1 KO mice. The histological analysis observed that ethanol exposure‐ AKR1A1eGFP/eGFP mice developed fatty liver syndrome, but not observed in the ethanol exposure‐CD‐1 control mice. In conclusion, we demonstrated that chronic exposure of alcohol lead to lack of hepatic steatosis and inflammation in AKR1A1 KO mice, which may provide a novel insight into the role of AKR1A1 in alcoholic liver disease.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Honokiol and Pioglitazone Ameliorate Alzheimer's Disease Pathologies in vitro and ex vivo
Authors: Lynd Tyler , Govindarajulu Manoj , Dhanasekaran Murali , Suppiramaniam Vishnu
Published: June 2021

Amyloid beta (AB) plaques are extracellular, neurotoxic protein aggregations. These plaques have historically been considered the hallmark of Alzheimer's disease due to their ability to reduce long term potentiation (LTP) and promote long term depression (LTD). Peroxisome proliferator‐activated receptor gamma (PPARg) agonists have been shown to be a novel and promising class of drugs capable of alleviating AD pathologies. In this study, we observed the neurotoxic effects of amyloid beta on hippocampal field potentials on the Schaffer collateral. In addition, we displayed honokiol, a novel SIRT3 and partial PPARg agonist, and pioglitazone, a full PPARg agonist, is capable of improving mitochondrial function, increasing LTP, and reducing AB aggregation. The hippocampal field potential along the Schaffer collateral was measured by the LTP theta burst protocol, while signaling mechanisms were evaluated using western blot, RT‐qPCR, mitochondrial assays, and imaging techniques. We hypothesize and provide evidence that these compounds regulate mitochondria‐endoplasmic reticulum communication in order to modify AD pathologies providing evidence for the MAM hypothesis. Both compounds performed comparably suggesting honokiol may be a promising compound for the treatment of AD as its blood brain barrier (BBB) permeability is much higher than pioglitazone.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Cell‐Specific Role of Aryl Hydrocarbon Receptor in Liver Fibrosis
Authors: Yan Jiong , Xie Wen
Published: June 2021

Background & Aims

The role of aryl hydrocarbon receptor (AhR) in liver fibrosis is controversial, because both AhR ablation and AhR activation lead to liver fibrosis. The liver is an organ of multiple cell types, including hepatocytes, hepatic stellate cells (HSCs) and Kupffer cells. We investigated cell‐type specific role of AhR in liver fibrosis and the specific inhibitory effect of AhR in HSC activation.

Methods

Primary mouse and human stellate cells and LX2 cell line were used to characterize the in vitro function of AhR in the HSC activation. Hepatocytes‐, HSCs‐, and Kupffer cells‐specific AhR knockout and AhR−/− mice were used to study the role of AhR in the spontaneously developed liver fibrosis and carbon tetrachloride (CCl4)‐ and bile duct ligation (BDL)‐induced liver fibrosis in vivo. Activation of HSCs and fibrotic phenotype were measured by quantitative real‐time PCR and Western blot analysis of fibrogenic genes, immunofluorescence of α‐smooth muscle actin (α‐SMA) and Ki67, and histological analysis.

Results

AhR is highly expressed in HSCs and declines with the onset of HSC activation in the primary HSCs. AhR−/− HSCs exhibited accelerated culture‐induced activation. AhR antagonist promoted while agonist inhibited the HSC activation, respectively. Ablation of AhR in HSCs was sufficient to sensitize mice to liver fibrosis.

Conclusions

AhR is an intrinsic suppressor for HSC activation and liver fibrosis. Development of non‐toxic AhR agonists or strategies that preferentially activate AhR in the HSCs represent a novel therapeutic for liver fibrosis.

Support or Funding Information

NIH DK083952

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Development of novel inhibitors of swelling‐activated LRRC8 anion channels
Authors: Figueroa Eric , Fulton Mark , Kharade Sujay , Kramer Meghan , Weaver David , Lindsley Craig , Denton Jerod
Published: June 2021

Cells critically regulate their volume in response to hypoosmotic swelling by transporting chloride and small organic osmolytes out of the cell through so‐called volume‐regulated anion channels (VRACs). The 5 genes encoding VRACs were recently identified in two independent genome‐wide siRNA screens and are named LRRC8 (for Leucine Rich Repeat Containing) A‐E. LRRC8‐containing VRACs have recently been implicated in drug uptake, adipocyte size, and insulin signaling. Unfortunately, the pharmacological tools available to study the physiology and therapeutic potential of LRRC8 channels is limited to low‐affinity small‐molecule inhibitors that exhibit promiscuous activity toward other anion channels, cation channels, and myriad other off‐targets. To circumvent this barrier, we are employing high‐throughput screening (HTS) of small‐molecule libraries and medicinal chemistry to develop more potent and specific inhibitors of LRRC8 channels. HTS will be performed using a fluorescence assay based on halide quenching of a YFP mutant (i.e. F46L, H148Q, I152L) termed Ozzy. Briefly, HEK‐293 cells stably transfected with Ozzy will be plated in black‐walled, clear‐bottomed 384‐well plates, treated with hypotonic solution containing compounds from the Vanderbilt Institute of Chemical Biology library, and then treated with sodium iodide (NaI). Cell swelling opens endogenously expressed VRAC channels, through which iodide enters the cell and quenches Ozzy fluorescence. Small‐molecule inhibitors should block the iodide‐induced quenching of Ozzy. Checkerboard analysis using the best‐in‐class VRAC inhibitor, DCPIB, yielded a Z′ value of 0.74, indicating the assay is reproducible and robust enough to ensure high‐confidence hit‐picking in a large‐scale screen. The assay also reports dose‐dependent inhibition of iodide influx by DCPIB with an IC50 of 11 micromolar, which is close to values derived from electrophysiological experiments. We are currently using this assay to interrogate an analog library based on the DCPIB scaffold, with the goal of identifying more potent and specific inhibitors of VRAC.

Support or Funding Information

Department of Anesthesiology Faculty Development Funds

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
LRRC26 is functional as an Auxiliary Subunit of Large‐Conductance Ca2+‐Activated K+ (BK) Channel and regulates BK channel activity in Bronchial Smooth Muscle Cells
Authors: Noda Sayuri , Suzuki Yoshiaki , Yamamura Hisao , Imaizumi Yuji
Published: June 2021

Large‐conductance Ca2+‐activated K+ (BK) channel activity is known to be an essential factor for the control of tone and/or motility in various types of tissues containing smooth muscle cells (SMCs) as one of main components. Recently leucine‐rich‐repeat‐containing proteins (LRRC) have been identified as novel auxiliary (γ) subunits of BK channel. However, the distribution and contribution of BKγ subunits in SMCs is unknown. We found that LRRC26 (BKγ1) is highly and specifically expressed in mouse bronchial SMCs (mBSMCs). In the present study, we examined functional roles of BKγ subunits in mouse bronchial SMCs (mBSMCs). Co‐immunoprecipitation and single molecule image analyses showed the direct interaction between BKα and BKγ1 in BSMCs. Whole‐cell patch‐clamp analyses revealed that BK channel sensitivity to intracellular Ca2+ concentration was much higher in mBSMCs than that in mouse aortic SMCs (mASMCs). Mallotoxin, which activates BK channels only in the absence of BKγ1, dose‐dependently activated BK channel currents in mASMCs, but not in mBSMCs. Knock‐down of BKγ1 in mBSMCs significantly reduced BK channel Ca2+ sensitivity and contraction induced by a BK channel blocker. Taken together, BKγ1 in mBSMCs substantially contributes to keep BK channel activity high and the resting membrane potential deep under resting conditions. Thus, BKγ1 in mBSMCs may be responsible to keep the airway resistance stably low under physiological conditions.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Changes in the participation and expression of angiotensin II receptor At1 in heart and kidney of rats 6 weeks old with neonatal administration of de dexametasone and hyperbaric oxygen therapy
Authors: Duron‐Gil Alejandra , Guevara‐Balcazar Gustavo , Martinez‐Godinez Maria Angeles , Rubio‐Gayosso Ivan , Franco‐Vadillo Antonio , Castillo‐Hernandez Maria Carmen
Published: June 2021

One therapy that has demostrated that it normalize the cardiovascular responses of angiotensin receptor in one experimental model, is the hyperbaric oxygen therapy. It has been described the wide use of dexametasone during the neonatal period of time, having different and controversial responses. Dexametasone has been used commonly due to the improvement in the lung function into the respiratory difficulty syndrome. Some studies reports that the use of steroid during the neonatal period could have some beneficial effects but also it could induce cardiovascular and renal disorder during the development. As it has been described one of the main pathway involved is the renin‐aldosterone‐angiotensin system. Some researchers describe that steroids regulate the angiotensin II receptor and function.

Objetive

the main idea is to analize the modification of the expression of angiotensin II receptor in rat with administration neonatal of dexametasone with/without hyperbaric oxygen therapy.

Methodology

neonatal rat (2 days) were administrated with dexametasone and were divided in 2 groups one with hyperbaric oxygen therapy and the other without therapy. At the age of 6 weeks the animals were sacrificed, and the expression of the receptor At1 were measured in the heart and the kidney by PCR and inmunohistochemistry.

Results

The group only with dexametasone showed has major expression of At1 receptor, however the group with dexametasone and hyperbaric oxygen therapy has a reduction in the expression of this receptor.

Conclusion

This results could suggest that the hyperbaric oxygen therapy could normalize the expresion in this rats with dexametasone treatment, being beneficial because it could reduce the possibility of one cardiovascular pathology like and infarct.

Support or Funding Information

SIP, COFAA, IPN

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Arginase inhibition improves vascular function and restores NO production in diabetic conditions
Authors: Shatanawi Alia , Momani Munther S.
Published: June 2021

Cardiovascular complications of diabetes are a leading cause of morbidity and mortality. Vascular endothelial dysfunction (VED) is strongly implicated in the pathogenesis of diabetic vascular complications. Diabetes has been linked to elevated arginase and associated with vascular endothelial dysfunction. The pathological process is characterized by impaired endothelial cell production of nitric oxide (NO) and/or decreased NO bioavailability. NO is produced by activity of endothelial NO synthase (eNOS) on its substrate L‐arginine. Arginase in ECs also uses L‐arginine as a substrate to produce urea and ornithine. Thus, elevated levels of arginase will limit availability of L‐arginine to eNOS and decrease NO production.

We performed analysis of arginase activity in type 2 diabetes mellitus (T2DM). Arginase activity was elevated in diabetes patients as compared to age‐matched healthy volunteers. Levels of arginase activity had a positive correlation with HbA1c levels in diabetic patients (R2=0.8 Pearson r=0.87). Cell studies also agreed with these findings, as high glucose (25 mmol/L, 72 hrs) treatment to ECs resulted in a significant increase in arginase activity. This increase in arginase activity was concomitant with a 27% drop in NO produced by EC. Inhibition of arginase by ABH (100 uM) restored NO level to normal.

The effects of L‐citrulline, a natural arginase inhibitor, on inhibiting arginase activity in T2DM patients was assessed. Twenty five patients received L‐citrulline supplements (2000 mg/day) for 1 month. Arginase activity was decreased 30% in T2DM patients after taking L‐citrulline supplements. There was a modest improvement on HbA1c levels in these patients. The effect on L‐citrulline on arginase activity was also measured in BAECs grown in high glucose conditions. L‐citrulline 100μM completely prevented the increase in arginase activity and restored NO production levels. These data indicate that inhibiting arginase activity can have therapeutic benefits in diabetic patients by preventing vascular dysfunction and maintaining NO levels.

Our results indicate that arginase can be regarded as a novel marker for the vascular complications of diabetes. Drugs targeting arginase or its signaling pathway may show benefits in delaying or preventing these vascular complications.

Support or Funding Information

The University of Jordan deanship of research

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Electronic Cigarettes Impair Human Coronary Endothelial Function
Authors: Davoren Katherine , Rashid Mohamad , Nafeh Fida , Moy Norma , Elashoff Robert , Lindner Jonathan , Victor Ronald G.
Published: June 2021

Electronic (e‐) cigarettes are claimed—but unproven—to be less harmful than standard tobacco cigarettes, which are well known to impair coronary endothelial function and constitute a major cardiovascular risk factor. To determine whether e‐cigarettes cause impairment in human coronary endothelial function, we compared effects of tobacco cigarette smoking and e‐cigarette use to blunt the normal increase in myocardial blood flow (MBF) quantified by contrast enhanced echocardiography perfusion imaging, induced by the exercise pressor reflex (post‐handgrip forearm vascular occlusion). The exercise pressor reflex is a reproducible stimulus to endothelial‐dependent coronary vasodilation while also increasing coronary sympathetic vasoconstrictor drive. The coronary endothelial function testing was performed in healthy young adult cigarette smokers (n=5) and age‐matched e‐cigarette users (n=8), ages 21–38 years: a) after overnight smoking/vaping abstinence; and b) immediately after smoking one Camel‐filtered cigarette or one standard use (15 puffs in 7 minutes) of a popular tank‐style e‐cigarette (Evod: battery 3.7 volts, nicotine content 18 mg). During tobacco abstinence in the young cigarette smokers, the exercise pressor reflex increased mean arterial pressure (MAP) by 21.6 ± 4 mmHg (mean ± SE) and increased MBF by 66 ± 20% over baseline (p<0.05), the latter indicating endothelial‐dependent vasodilation in the human coronary microcirculation. As expected, the MBF failed to increase when the exercise pressor reflex was elicited immediately after cigarette smoking (Δ MBF −2 ± 24%, p=n.s.), indicating acute impairment in coronary endothelial function. The surprising new findings of this study are that MBF also failed to increase and tended to decrease by −45 ± 20% (p=n.s.) when the exercise pressor reflex was elicited immediately after acute e‐cigarette use and by −16 ± 10% (p=n.s.) even when elicited during vaping abstinence (despite comparable mean reflex increases in MAP of 21.1 and 21.6 mm Hg, respectively). Thus, our data to date suggest that, in contrast to what has been widely assumed, e‐cigarette use in young adults causes an impairment in coronary endothelial function that appears to be more persistent than with traditional tobacco cigarettes. Further research is warranted to determine if specific oxidant nanoparticles in e‐cigarette vapor mediate the impaired coronary endothelial function.

Support or Funding Information

Funded by Tobacco Related Disease Research Program; ClinicalTrials.gov NCT02612701

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Spironolactone Prevents Elevated Expression of Vascular ENaC in Hypertension
Authors: Mugloo Sama , Ashley Zoe , Leader Catherine , bahn Andrew , Sammut Ivan , Walker Rob , McDonald Fiona , Fronius Martin
Published: June 2021

Epithelial sodium channel (ENaC) in the kidneys plays an important role in maintaining salt/water homeostasis and blood pressure. Recent research has demonstrated expression of ENaC in the vasculature, and a new role in regulation of the vascular tone. An increase in vascular tone is seen in vascular diseases such as hypertension indicating that changes in ENaC expression in the vasculature may contribute to hypertension. In this study, we hypothesized ENaC expression in arteries will increase in hypertension and that the treatment with antihypertensive drug, spironolactone (spiro‐) will reduce ENaC expression in arteries.

Conduit (aorta) and resistance (mesenteric) arteries from male transgenic rats (Cyp1a1‐ren2) with diet‐inducible hypertension (0.167% indole‐3‐carbinol) were isolated and a‐, b‐ and g‐ENaC expression was analyzed by qRT‐PCR. Arteries from four animal groups were analyzed: (1) normotensive (2) hypertensive, (3) normotensive spiro‐ and (4) hypertensive spiro. Rats were fed a control or hypertensive diet for 6 weeks and in two groups (3 & 4) spiro‐ (4.41mg/kg/day) was introduced 2 weeks after the start of the diet.

In mesenteric arteries of hypertensive animals a significant increase in both a‐ENaC (p=0.02) and g‐ENaC mRNA level (p=0.04) was observed in comparison to normotensive arteries. In aortas, there was a significant increase in a‐ENaC mRNA level (p=0.006) in hypertension but no change in b‐ and g‐ENaC expression. In mesenteric arteries, spiro‐treatment decreased a‐ENaC and g‐ENaC in comparison to hypertensive controls. In aortas, a‐ENaC mRNA level was significantly decreased (p=0.002) by spiro‐treatment compared to hypertensive controls.

In summary, we observed an upregulation of vascular ENaC mRNA in arteries during hypertension and found that antihypertensive treatment with spironolactone decreased this upregulation. This data suggests a strong link between pathogenesis of hypertension and vascular ENaC expression.

Support or Funding Information

University of Otago Doctoral Scholarship, Department of Physiology, Otago Medical Research Foundation, Lottery Grants Board

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Preeclampsia alters the role of nitric oxide in androgen metabolite‐induced vasorelaxation of rat uterine artery
Authors: Hanson Andrea E. , McKenna Joshua M. , Garcia Nikolas W. , Perusquia Mercedes , Stallone John N.
Published: June 2021

Preeclampsia (PE) is a pregnancy‐induced disorder and a major cause of both fetal and maternal morbidity and mortality. During pregnancy, the placenta produces abundant androgens, and these rapid, non‐genomic vasodilators may serve to maintain uterine blood flow during normal pregnancy and may be impaired in PE. Of the known placental androgens, testosterone (TES) and its genomically inactive metabolite, 5β‐dihydrotestosterone (5β‐DHT), were previously reported to induce vasorelaxation in uterine arteries (UA). This study aimed to determine the nitric oxide (NO) signaling mechanisms involved in TES‐ and 5β‐DHT‐ induced relaxation in the rat UA using the DOCA‐salt model of PE. Endothelium‐intact UA rings (200 μm, dia.) from normal pregnant (NP) and DOCA‐treated pregnant (DSP) female (F) Sprague‐Dawley rats (250–300g) were prepared for measurements of isometric contractile force (DMT myograph). UA were pretreated with L‐NG ‐monomethyl arginine citrate (L‐NMMA, 100 μM), a non‐selective nitric oxide synthase (NOS) inhibitor or NW‐propyl‐L‐arginine (200 nM), a specific nNOS inhibitor. UA were then precontracted with U‐46619 (thromboxane A2 agonist, 1 μM) and a concentration‐dependent relaxation to TES and 5β‐DHT was obtained (0.1–1000 nM). Data are means ± SE (n = 6 rats). Androgen‐induced maximal UA relaxation was reduced by L‐NMMA in NP (TES: 33.84 ± 4.6 vs. 1.24 ± 4.0 and 5β‐DHT: 28.12 ± 6.1 vs. 2.0 ± 6.3) and in DSP (TES: 36.23 ± 4.6 vs. 4.44 ± 2.3 and 5β‐DHT: 30.71 ± 4.6 vs. 0.9 ± 2.4). Maximal relaxation was reduced by NW‐propyl‐L‐arginine in NP for both TES (24.53 ± 6.1) and 5β‐DHT (20.38 ± 3.8) and in DSP for 5β‐DHT (18.78 ± 6.7); however TES induced UA relaxation was unchanged with NW‐propyl‐L‐arginine in DSP (33.60 ± 10.4). These data suggest that: 1) androgen‐induced UA relaxation is both nNOS and eNOS dependent in NP; and 2) nNOS dependent TES‐induced relaxation of UA is decreased in DSP. (State of Texas)

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of H1/H2 histamine receptor blockade on mitochondrial function in rodent brain following prolonged exercise
Authors: Wallace Helen E. , Davidson Laura R. , Bell Mackenzie CW. , Brebner Karen , Kane Daniel A.
Published: June 2021

Exercise has been shown to stimulate histamine release, which mediates vasodilation in exercising tissue and is sustained post‐exercise. Blockade of H1 and H2 receptors with antihistamine drugs attenuates this effect in skeletal muscle. Research examining the effects of exercise‐related histamine action on cellular level processes is relatively sparse. There also remains limited understanding of the impacts of histamine receptor blockade on non‐exercising tissue, such as the brain. To this end, 36 adult male Wistar rats (75–94 days old, 441.2 ± 39.5 g body wt) were randomly assigned to three groups: (1) given H1 and H2 receptor antagonists fexofenadine (7.11 mg/kg) and ranitidine (3.95 mg/kg) via oral gavage 1 hr prior to treadmill exercise (1 hr, 20 cm/s); (2) completed the exercise without drug, and (3) control. All groups received body mass‐proportional oral gavage volumes (water or antihistamines). One hour post‐exercise, mitochondrial function was assessed in saponin‐permeabilized prefrontal cortex and dorsal hippocampus brain sub‐regions. There was no effect of exercise or drug treatment on mitochondrial substrate‐dependent oxygen consumption (JO2; high‐resolution respirometry), or in mitochondrial hydrogen peroxide emission (mH2O2; fluorometric monitoring of Amplex Red oxidation) in permeabilized prefrontal cortex or the dorsal hippocampus. These results suggest negligible effects of oral H1/H2 antagonists on mitochondrial metabolism in brain following exercise. This supports prior evidence suggesting the effects of H1/H2 inhibition remain localized in exercising muscle. Other studies report systemic increases in histamine levels following exercise, however, which suggests further research may reveal a relationship between histamine receptor blockade and cellular processes in non‐exercising tissues.

Support or Funding Information

The Natural Sciences and Engineering Research Council of Canada (NSERC), The Nova Scotia Health Research Foundation (NSHRF), and Canada Foundation for Innovation (CFI)

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The TLQP‐21 neuropeptide and the complement 3a receptor (C3aR1) regulate a novel prolipolytic pathway
Authors: Sahu Bhavani Shankar , Cero Cheryl , Han Ruijun , Razzoli Maria , Grady Scott O. , Bartolomucci Alessandro
Published: June 2021

Obesity results in fat mass accumulation and is associated with serious comorbidities such as type 2 diabetes and cardiovascular disease. Targeting excess fat by lipolysis has been a major challenge due to side effects. TLQP‐21, a neuropeptide encoded by the pro‐peptide VGF (nonacronymic), that binds the complement 3a receptor 1 (C3aR1) on the adipocyte membrane, is emerging as a novel modulator of adipocyte functions and a potential target for obesity. However, the molecular mechanism is still largely uncharacterized. In current study, we aim to understand the role of C3aR1 in murine, human adipocytes and in vivo in diet‐induced obese mice. In vitro experiments using loss and gain of function approaches in 3T3‐L1 adipocytes demonstrate that C3aR1 knockdown prevents TLQP‐21‐induced prolipolytic response. Likewise, TLQP‐21 treatment decreases body weight and fat mass in diet induced obese mice by a mechanism requiring C3aR1 activation. Finally, we demonstrate that this lipolytic pathway is conserved in human adipocytes and can be activated by the rodent but not the human TLQP‐21 peptide, a finding in line with our previous demonstration of a low potency of the human compared to the rodent TLQP‐21 at the human C3aR1 (Cero et al., Structure 2014). In summary, our results identified a novel lipolytic pathway involving TLQP‐21 and C3aR1, a receptor classically studied for its role in innate immunity thus offering a novel target to develop new effective pharmacotherapies for obesity and associated diseases.

Support or Funding Information

NIH grant (NIH/NIDDK R01DK102496)

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
A feedback control of insulin signaling by transcription factor HMG box‐containing protein 1 (HBP1) in adipocytes
Authors: Chen Zih‐Hua , Chan Chien‐Yi , Lee Ming‐Fen , Huang Chun‐Yin
Published: June 2021

Adipocytes are sensitive to insulin control of cellular glucose utilization, thereby facilitating the maintenance of blood glucose concentration. Previously we demonstrated that transcription factor HBP1 is highly expressed in differentiated adipocytes, which, together with CCAAT/enhancer‐binding proteins C/EBPβ and C/EBPα, regulates adipocyte differentiation. To further gain insight into the biological role of HBP1 in mature adipocytes, here, we employed mouse embryonic fibroblast (MEF)‐derived adipocytes to test the hypothesis that HBP1 might regulate insulin sensitivity in adipocytes. First, suppression of HBP1 by siRNA‐mediated gene silencing significantly attenuated glucose uptake as shown by 2‐NBDG glucose uptake assay. We then examined the insulin‐signaling pathway to unravel the molecular mechanism by which HBP1 commands adipocytes to take up glucose. Under serum starvation, the transcription of insulin receptor (InR) was increased, whereas HBP1 silencing down‐regulated the expression of InR in adipocytes, indicating that HBP1 is able to promote insulin sensitivity under insulin insufficient state. However, the addition of insulin (2 nM for 6 h) led to a significant decrease in the transcription of HBP1, InR, and IRS1/2 (insulin receptor substrate 1/2). Moreover, HBP1 siRNA led to increased level of p‐S307 IRS‐1 that is associated with blockade of the insulin signaling, and also resulted in an unexpected induction of glucose transporter 4 (GLUT4). The upregulation of GLUT4 may function as a compensation mechanism for the defective insulin signaling caused by HBP1 silencing. Taken as a whole, our results reveal a key feedback control mechanism for HBP1 in regulating insulin signaling and glucose metabolism.

Support or Funding Information

This work was supported by the grant to MOST 105‐2320‐B‐039‐044‐MY2 C‐Y Huang.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.