bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of menstrual cycle phase on the cerebrovascular response to hypoxia: role of cyclooxygenase (708.1)
Authors: Peltonen Garrett , Rosseau Cameron , Harrell John , Schrage William 
Published: June 2021

Menstrual phases influence resting cerebral blood flow (CBF), partially through cyclooxygenase (COX) mediated signaling. It is unknown if menstrual cycle hormone variations influence the CBF response to hypoxic stress. Compared to early follicular phase, we hypothesized females in early luteal phase would exhibit a larger, COX‐dependent, hypoxia‐mediated increase in CBF. We measured middle cerebral artery velocity (MCAv) with transcranial Doppler ultrasound in 4 healthy females (22 ± 3 yrs). Cerebral vascular conductance index (CVCi = MCAv*100/MABP) was calculated to normalize for potential differences in blood pressure. Females were studied twice each in early follicular (cycle day 1‐5) and late luteal (cycle day 12‐16) phases of the menstrual cycle, with and without COX inhibition (100 mg oral Indomethacin, Indo). Arterial O2 (SaO2) was reduced to 80% for 5 minutes while clamping end‐tidal CO2. On average, estrogen was higher (188 vs. 55 pg ml‐1) and progesterone was similar (790 vs. 603 pg ml‐1) during early luteal phase. Menstrual phase had no effect on basal CVCi (p=0.67) or the decrease in basal CVCi with Indo (p=0.45). Hypoxia increased CVCi (∆CVCi = 12 ± 1 cm s‐1 mmHg‐1; p<0.001), but the hypoxia‐induced ∆CVCi was not altered by menstrual phase (p=0.53) or Indo (p=0.873). These data suggest that menstrual phase does not alter basal or hypoxic CVCi and the role of COX is unchanged in either response.Grant Funding Source: NIH R01 HL105820 & AHA PRE7390038
Tryptophan diet deficiency, intermittent hypoxia exposure and DNA methylation: implications in SIDS (710.10)
Authors: Lee Stella , Luikart Bryan , Nattie Eugene 
Published: June 2021

The Sudden Infant Death Syndrome (SIDS) is the unexpected, sudden death of an infant in which an autopsy and a death scene investigation do not find a cause of death. Here, we focus on the role of brainstem serotonin (5‐HT) deficiency in SIDS pathogenesis as suggested by studies in SIDS cases. Further, a recent discovery of the effects of neonatal chronic intermittent hypoxia (CIH), a postulated occurrence in many SIDS cases, on DNA methylation as measured in adult rats suggests a potential role of epigenetics in the pathogenesis of SIDS. The present study investigated the effects of neonatal CIH on DNA methylation in rat pups treated with control vs. tryptophan deficient diets, the latter known to induce a brainstem 5‐HT deficiency. Our data suggest that global DNA methylation in the medulla increased significantly with tryptophan deficiency (Two way ANOVA, p<0.001) whereas exposure to CIH decreased it (p<0.001). Interestingly, there was a significant interaction effect between diet and CIH (p = 0.010). Similarly, DNA methylation in the raphe increased with tryptophan deficiency whereas the addition of CIH decreased it, demonstrating a significant interaction between diet and CIH (p = 0.029). Thus we find that two different risk factors associated with SIDS can result in epigenetic modification in the brainstem. It is unclear what the role of such epigenetic modification is in the context of 5‐HT deficiency, CIH and SIDS.Grant Funding Source: Supported by National Institute of Child Health and Human Development Grant PO1‐HD‐036379
Xanthine oxidase activation mediates intermittent hypoxia increased NADPH oxidase activity (710.3)
Authors: Nanduri Jayasri , Vaddi Damodara , Khan Shakil , Wang Ning , Makarenko Vladislav , Prabhakar Nanduri 
Published: June 2021

We previously showed that NADPH oxidases (Nox) especially Nox2 mediate systemic and cellular responses to intermittent hypoxia (IH). However, the mechanisms by which IH activates Nox2 have not been examined. We recently reported that xanthine oxidase (XO) activation by IH generates ROS which leads to increased intracellular calcium. Given that calcium activated PKC is required for Nox2 activation, we tested the hypothesis that XO activation mediates IH increased Nox activity via ROS augmented calcium. Allopurinol, a XO inhibitor or silencing of XO in PC12 cells prevented IH‐induced Nox2 activation by inhibiting Nox2 complex formation at the membrane. Treatment of cells with Xanthine/XO under normoxia mimicked the effects of IH. Our results further demonstrate that ROS generated by XO, contribute to IH induced Nox activation by increasing intracellular calcium levels. IH augmented PKC activity by phosphorylation of alpha subunit which was inhibited by allopurinol and BAPTA (calcium chleator). More importantly, inhibition of PKC activity by allopurinol abolished Nox2 complex formation. These results demonstrate that ROS generated by XO activates PKC alpha via calcium resulting in IH augmented Nox activity. Supported HL‐ ‐90554.Grant Funding Source: HL‐90554
Different sub‐populations of pre‐sympathetic neurons are revelead by acute hypoxia in brainstem slices of adult rats (710.7)
Authors: Karlen‐Amarante Marlusa , Almado Carlos , Accorsi‐Mendonça Daniela , Machado Benedito 
Published: June 2021

In this study we evaluated, in brainstem slices from adult rats, the effects of acute hypoxia (AH) on the firing rate of pre‐sympathetic neurons in rostral ventrolateral medulla sending projections to the intermediolateral column of spinal cord (RVLM‐IML neurons). Anesthetized male Wistar rats (PO 30) were submitted to microinjection of fluorescent retrograde tracer into the spinal cord (T3‐T5) to label the RVLM‐IML neurons. Five days later the rats were anesthetized to obtain brainstem coronal slices. The RVLM‐IML neurons were recorded using whole‐cell patch‐clamp and the firing rate was analyzed before and after perfusion of slice to AH for 2 minutes with hypoxic solution (95% N2 and 5% CO2) in the presence of synaptic blockers. After the AH protocol the viability of RVLM‐IML neurons were verified by the perfusion with normal solution (95% O2 and 5% CO2). All recorded RVLM‐IML neuronsof adult rats (n=17) presented intrinsic spontaneous firing activity. Three sub‐populations of RVLM‐IML neurons were identified after AH exposure: a) 3 neurons decreased their firing rate after AH(‐ 34,10%, p= 0,0225); b) 4 neurons increased their firing rate after AH (+ 40,86%, p= 0,0249) and c) 10 neurons were not affected by AH(± 3,54%, p= 0,5380. Hypoxia produced no changes in input resistance and resting membrane potential in these neurons. The data show that pre‐sympathetic neurons in the brainstem slices of adult rats present pacemaker activity and different sub‐populations of pre‐sympathetic neurons are revealed in response to AH.Grant Funding Source: Supported by FAPESP and CNPQ
Primary screening of siRNA to determine genes involved in vascular leakage (711.3)
Authors: Hoke Allison , Jibitu Meskerem , Gautam Aarti , Hammamieh Rasha , Jett Marti 
Published: June 2021

Endothelial cells lining the vessels of the vasculature and the cell‐cell junctions provide the primary barrier for the passage of fluids, immune cells, and macromolecules between the bloodstream and tissues. Appropriate and dynamic regulation of this barrier is required for normal physiological processes. To identify genes implicated in vascular leakage, we combined siRNA knockdown screens with an in vitro assay that models the human endothelium by using primary human microvascular endothelial cells (HMVEC‐L) plated on a 96‐transwell collagen‐coated filter unit. To investigate genes related to vascular leakage, a primary screen of ~500 siRNAs against drugable target genes was performed and the cells were plated for 48 hours for monolayer formation. The monolayer permeability was evaluated using dextran‐FITC to detect leakage through small gaps present in the early stages of permeability induction. The viability of the siRNA knockdown HMVEC‐Ls was also determined. We have identified genes from the primary screen that lead to increased permeability when knocked down. These results need to be validated. With the application of this in vitro assay, genes relating to vascular leakage can be more fully investigated and the siRNA knockdown results will help identify genes with a potential for therapeutic roles.Grant Funding Source: Supported by the Transformational Medical Technologies program contract TMTI.DRUG.02.10.WR.023.
Induction of ectopic inflammasome function in fetal lung mesenchyme (715.4)
Authors: McCoy Alyssa , Greer Rachel , Prince Lawrence 
Published: June 2021

Bronchopulmonary Dysplasia (BPD) commonly affects preterm infants. Inflammation and the soluble inflammatory mediator interleukin‐1 beta (IL‐1beta) play major roles in BPD pathogenesis and inhibit normal lung airway formation. IL‐1beta release requires both NF‐kappaB dependent mRNA expression and post‐translational cleavage by caspase‐1 containing inflammasomes. Best characterized in immune cells, the inflammasome has not been investigated in the developing lung. Here we test the hypothesis that the endotoxin lipopolysaccharide (LPS) can induce ectopic inflammasome expression in fetal lung mesenchyme, leading to IL‐1beta release. In primary fetal mouse lung mesenchymal cells, LPS rapidly induced IL‐1beta mRNA expression, but neither LPS nor the inflammasome activator ATP stimulated the release of IL‐1beta peptide. However, treating mesenchymal cells with LPS for at least 6h and then stimulating with ATP did release IL‐1b peptide, suggesting LPS‐dependent priming. These results were consistent with immunoblots showing caspase‐1 cleavage when mesenchymal cells were primed with LPS and then activated with ATP. LPS priming also increased caspase‐1 mRNA expression. Mesenchymal cells expressing a constitutively active IKKbeta contained higher levels of IL‐1beta and inflammasome component mRNA, but did not release IL‐1beta peptide unless first primed with LPS and then activated with ATP. These data suggested that IKKbeta activity might not be sufficient to assemble a fully functional inflammasome. These data show that LPS can generate functional inflammasome expression and function in lung mesenchymal cells, potentially propagating the release of inflammatory cytokines within the lung.Grant Funding Source: Supported by 2R25GM059994‐14 and 5R01HL097195‐02
Role of hepatic microsomal oxidation in regulation of monoamine oxidase mediated processes in rat brain (727.1)
Authors: Tseylikman Vadim , Manukhina Eugenia , Downey H , Tseylikman Olga , Kozochkin Denis , Deev Roman , Misharina Mariya , Misharina Mariya , Komelkova Mariya 
Published: June 2021

Monoamine oxidase (MAO) plays a key role in metabolism of biogenic amines and serves as a marker of alcoholism and depressive disorders. Various isoforms of cytochrome This study was focused on the relationship between MAO activity and hepatic content of cytochrome P450 which reflects the state of microsomal oxidation. Methods. For vital integrative evaluation of hepatic microsomal oxidation in rats, the hexobarbital sleep test was used. Content of cytochrome P450 was measured in hepatic microsomes. Activities of MAO‐A and MAO‐B were measured in the whole brain and brain structures. Content of serotonin, a MAO substrate was measured in the brain and plasma. Intensity of oxidative stress was evaluated by measuring lipid peroxidation products and carbonylated proteins in brain. Results. Rats with short hexibarbital sleep time (SHST) had higher content of microsomal cytochrome P450 than rats with long hexobarbital sleep time (LHST). Whole brain MAO‐A and MAO‐B activities, serotonin and carbonylated protein levels were higher in SHST than LHST rats. MAO‐A and MAO‐B activities were higher in brain cortex of SHST rats; only MAO‐A activity was higher in hypothalamus and medulla of LHST. The same brain regions of LHST rats had higher concentrations of carbonylated proteins and lipid peroxidation products. Conclusion. Data obtained in this study showed a correlation between MAO activity and microsomal oxidation phenotype. Rats with higher hepatic content of cytochrome P450 had higher activities of MAO‐A and MAO‐B in the brain and higher plasma serotonin levels than rats with lower microsomal oxidation. These correlations may reflect contribution of biogenic amines to regulation of cytochrome P450‐dependent monooxygenases and a role of cytochrome P450 in metabolism of biogenic amines and hormones regulating MAO activity including glucocorticoidsGrant Funding Source: Russian Foundation for Basic Research grant 11‐04‐01378‐а&14‐04‐01381‐a
Anti‐ inflammatory effects of thymoquinone in LPS‐ stimulated BV‐2 murine microglia cells (730.2)
Authors: Taka Equar , Mazzio Elizabeth , Goodman Carl , Reeams Renee , Soliman Karam 
Published: June 2021

Thymoquinone (TQ) is one the main pharmacologically active constituents of the black cumin seeds (Nigella sativa) believed to be responsible for therapeutic effects on chronic inflammatory conditions such as arthritis and asthma. In this study, we investigate the possible neuroprotective action of TQ in activated microglia cells. We hypothesized that the anti‐inflammatory properties of TQ are mediated in part by inhibiting the formation of pro‐inflammatory cytokines, chemokine’s and other inflammatory mediators. In this study, we evaluated the anti‐inflammatory activity of TQ in lipopolysaccharide (LPS) (1µg/ml) stimulated microglia cells in the presence or absence of TQ (10µM). Cytokines/chemokine's were profiled using a RayBio antibody protein array and NO release was evaluated using the Griess reagent assay. In addition, cytokine antibody array results were validated using PCR array and ELISA. Our results showed that TQ significantly inhibited Pro‐inflammatory cytokines including IL‐6, IL‐1β, IL‐12p40/70, Growth Colony Stimulating Factor (G‐CSF), and pro‐inflammatory chemokine’s such as MCP‐5, IP‐10, MCP‐1 and inflammatory mediators NO production in LPS stimulated BV‐2 cells. In conclusion, the results obtained suggest that TQ could have a neuroprotction potential and may provide a mean for the treatment of neuro‐inflammation that occurs in neurodegenerative diseases such as Alzheimer and Parkinson’s diseases.Grant Funding Source: Supported by NIH grants NIMHD G12 MD007582 and P20 MD006738
Features of finger and palm papillary pattern as morphological markers of individual predisposition to type 2 diabetes (734.6)
Authors: Sarapultsev Alexey , Sarapultsev Petr , Yakusheva Marina 
Published: June 2021

The goal of the research is detecting morphological markers of individual predisposition to development of type 2 diabetes metabolic disorders. At the first stage of the research, features of papillary pattern of 126 people were observed ‐ 63 type 2 diabetes patients were examined and 63 people of the control group formed by the method of “directional selection” according to such parameters as age, gender, nationality, no diabetes. It included studying the dermatoglyphic pattern taken by the specially designed fingerprint scanner. The second stage studied interconnections of the features of papillary pattern and anthropometric measurements (body weight, body mass index, waist circumference, hip circumference) with laboratory parameters normal ranges (С‐peptide, immunoreactive insulin, glycosylated hemoglobin, fasting glycemia, insulin resistance index, cholesterol, triglycerides, lipoproteins) for 70 type 2 diabetes patients.The results received testify to the existence of papillary pattern features with type 2 diabetes patients, distinguishing them from practically healthy people having no obesity or carbohydrate metabolism disorder. The presence of complicated palm patterns indicates possible disorders in the hypothalamo‐pituitary axis and predisposition to development of dysmetabolism.
An asymmetric gene evolution mechanism via replication‐transcription conflicts (735.11)
Authors: Merrikh Houra , Million‐Weaver Samuel , Nakta Samadpour Ariana 
Published: June 2021

Bacterial genomes are generally biased such that most genes are encoded on the leading strand, in a co‐directional manner to DNA replication. This presumably avoids the potentially detrimental head‐on collisions that occur between the replication and transcription machineries when genes are encoded on the lagging strand. However, despite this co‐orientation bias, a significant number of highly conserved and essential genes remain head‐on to replication and are encoded for on the lagging strand. Our work, in the model organism Bacillus subtilis, led to the hypothesis that bacterial cells keep some genes in the head‐on orientation, in part, to accelerate their adaptive evolution in a targeted manner. Using both bioinformatics analyses and experimental data, we proposed that this targeted evolution mechanism is driven, at least in part, by the collisions between replication and transcription machineries. Our recent unpublished results are consistent with this hypothesis, and indicate that the asymmetric nature of how these conflicts impact the genome is indeed the major driving force behind this targeted and orientation‐dependent mutagenesis mechanism. Altogether, these findings have deepened our understanding of the impact of replication‐transcription conflicts on asymmetric mutagenesis, genome organization and evolution in bacteria. Because the underlying mechanisms are highly conserved in many species, this work potentially has far‐reaching implications beyond the bacterial world.Grant Funding Source: Supported by NIH DP2GM110773
MLH3, a minor player in mismatch repair, is a major force in GAA•TTC repeat expansion (736.9)
Authors: Fuselier Kayla , Grabczyk Ed 
Published: June 2021

Friedreich ataxia (FRDA) is a progressive neurodegenerative disorder caused by GAA·TTC repeat expansion in the first intron of the frataxin (FXN) gene. Disease severity correlates with the length of the expanded repeats and the reduction of FXN mRNA. Our objective is to refine our understanding of the role mismatch repair proteins play in the repeat expansion that causes FRDA. We have previously shown that the expansion rate is associated with transcription within the repeat and requires MutSβ and the subsequent action of a MutL complex. We now demonstrate that the necessary complex is MutLγ, a heterodimer of MLH1 and MLH3. We report here that our studies on MLH3 indicate that it is pivotal in GAA•TTC expansion in our human cell model system. MLH1 has a central role in all MutL complexes; whereas MLH3 is only a component of the MutLγ complex. Therefore, MLH3 may be the better potential therapeutic target for FRDA.Grant Funding Source: Supported by the Friedreich's Ataxia Research Alliance and the LSUHSC Research Enhancement Fund
Imaging of molecular oxygen at subcellular resolution in mammalian cell culture: from 2D to 3D models (764.1)
Authors: Dmitriev Ruslan , Kondrashina Alina , Foley Tara , Papkovsky Dmitri 
Published: June 2021

Oxygen monitoring is necessary for studying cell metabolism, stem cell development and ROS production, however most of the current methods suffer from low sensitivity and signal drift (electrodes), lack of quantitative context and end‐point nature (hypoxia stains) or inability to probe O2 inside the cell (extracellular probes). Phosphorescence lifetime imaging microscopy (PLIM) allows for quantitative, sensitive and specific detection of O2, by means of phosphorescent indicator dyes. We developed phosphorescent O2 probe (Pt‐Glc) which demonstrates efficient cytosolic staining of different cell lines (2D cultures), and 3D tissue models such as spheroids (primary neurospheres) and live brain slices from embryonic tissue. The PLIM analysis of neurospheres from rat brain cortex with Pt‐Glc confirmed presence of hypoxic niches. We correlated oxygenation map of spheroids with their size, distribution of live cell (cholera toxin, TMRM), proliferating (BrdU) and stem cell markers (nestin), thus performing multiplexed metabolic imaging of live neurosphere. A comparison with pimonidazole, HIF‐a immunostaining and nanoparticle probes was also made. Thus, Pt‐Glc represents valuable tool for studying stem cell niche within ex vivo and in vitro 3D models.Grant Funding Source: Supported by the Science Foundation Ireland.
Role of SET oncoprotein in epithelial‐mesenchymal transition and pancreatic cancer progression (784.3)
Authors: Hung Sau Wai , Lee Haesung , Gilbert Caitlin , Hoang Toan , Naidu Kineta , Govindarajan Rajgopal 
Published: June 2021

One of the key reasons for why pancreatic cancer has such a poor prognosis is that >80% of diagnoses occur when metastasis has already presented. At the cellular level, activation of the epithelial‐mesenchymal transition (EMT) is significant because it allows for the dissemination of primary tumor cells to distant sites. In this study, we sought to determine the role of a novel oncoprotein, SET, in EMT and pancreatic cancer cell progression. We found that silencing SET reverted EMT by inducing a cuboidal, epithelial morphology and reducing colony formation, cellular proliferation, migration, and invasion. Consistently, SET overexpression was detected in a subset of pancreatic tumors, especially poorly‐differentiated pancreatic ductal adenocarcinomas. Higher levels of SET protein expression were also identified in all pancreatic cancer cell lines compared with normal human pancreatic ductal epithelial cells. SET‐mediated EMT was determined to be a result of cadherin switching during which the SPARC/Slug and Rac1/JNK/c‐Jun/AP‐1 signaling pathways inhibit epithelial E‐cadherin and promote mesenchymal N‐cadherin, respectively. In brief, we elucidated a novel role for the SET protein in inducing EMT through cadherin switching and revealed the molecular pathways involved. These findings have implications for the design and targeting of pathways necessary for intervening pancreatic tumor progression.Grant Funding Source: Supported by NIH 1021RR571367 and 1021RR571381.
Necessity for EFGR kinase enzymatic activity in the coordinate upregulation of a chemoattractant gene suite by vasoactive intestinal peptide in mouse lymphocytes (784.5)
Authors: Saunders Jenna , Wanjara Steve , Hoselton Scott , Schuh Jane , Dorsam Glenn 
Published: June 2021

Vasoactive intestinal peptide (VIP) is a potent chemoattractant for immune cells that is delivered by the peripheral nervous system to immune organs. However, the molecular mechanism regulating VIP’s chemoattractant properties is not known. Previously, our group published the VIP transcriptome in resting CD4 T cells, which identified a chemoattractant gene set (e.g. EGFR, Snail and syt XIII) that was coordinately upregulated. We hypothesize that these gene products control the chemoattractant activity of VIP in immune cells. Moreover, we propose that this chemoattractant gene set is transcriptionally upregulated by the transactivation of EGFR by VIP as is observed in non‐immune cells, including breast and colon cancer cells. This research will utilize primary mouse splenocytes treated +/‐ VIP over various time intervals in an attempt to identify which FACS‐sorted splenocyte subpopulations are sensitive to VIP and the extent to which the chemoattractant gene set is upregulated. Optimal conditions will be repeated +/‐ EGFR neutralizing antibody or a specific EGFR kinase inhibitor to assess the contribution of EGFR enzymatic activity for the chemoattractant gene expression changes. Lastly, Boyden‐chamber chemotaxis assays will be employed to test whether pharmacological inhibition against EGFR kinase activity and/or other chemoattractant gene products suppresses VIP’s chemoattractant activity using identified splenocyte subpopulations. The significance of the proposed research is to better understand the molecular control of lymphocyte trafficking mediated by the nervous system.Grant Funding Source: This research was supported by NIH/NIAID (R15 to GD).