bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential regulation of mammalian tRNA synthetase genes by amino acid availability (818.7)
Authors: Shan Jixiu , Tang Tiffany , Han Jaeseok , Kaufman Randal , Kilberg Michael 
Published: June 2021

A low protein diet or one deficient in an essential amino acid (AA) triggers wide‐ranging changes in feeding behavior and gene expression. Mammalian cells have evolved capabilities to cope with this nutritional stress. Activation of either GCN2 (AA limitation) or PERK (ER stress) eIF2 kinases leads to a suppression of global protein synthesis but a paradoxical increase in the translation of selected mRNA species, among them is activating transcription factor 4 (ATF4). Elevated expression of ATF4 protein increases the transcription from a large number of genes involved in a wide spectrum of cellular functions. During ER stress, gene expression profiling showed that ATF4 interacts with another bZIP transcription factor, CHOP, to induce genes associated with protein synthesis, among them were selected tRNA synthetases. In this study, we have quantified the differential expression of all of the genes for the cytoplasmic and mitochondrial localized tRNA synthetases in both wild type and ATF4 KO MEFs in response to AA deprivation. About one‐half of the genes for the cytoplasmic synthetases were up‐regulated and most required ATF4, but only a few of the mitochondrial synthetases were modestly increased and those were largely independent of ATF4. Genomic analysis of the ATF4‐dependent genes revealed the contribution of a C/EBP‐ATF response element (CARE) sequence.Grant Funding Source: Supported by NIH: DK092062, DK094729 (MSK); HL057346, DK042394, DK088227, HL052173, DK093074 (RJK)
Effects of dairy ingredients on cytokine responses to LPS challenge in mice (822.5)
Authors: Price Tara , Baskaran Sangeetha , Walzem Rosemary 
Published: June 2021

Gut permeability to bacterial cell wall components, e.g.LPS, are thought to play a causative role in chronic systemic inflammation leading to disease. The effects of individual protein sources, namely isolated soy protein (ISP), dried whole milk powder (DWMP), milk fat globule membrane (MFGM) or milk protein concentrate (MPC) on cytokine responses to LPS (Salmonella) challenge was studied using whole blood from C57BL/6J mice (n=10/group) following 13 wk of test diet feeding. Isocaloric and isonitrogenous diets provided 20 EN% protein, 50 EN% carbohydrate and 30 EN% fat. Mice grew and consumed feed similarly. Multiplex assay for basal inflammatory cytokines showed lowest values for DWMP in all cases and significant for IL‐1β and TNF‐α (p<0.05). No differences in basal IL‐10 were observed. In response to LPS challenge IL‐12(p70), IFN‐γ, TNF‐α and MIP‐2 were unchanged. Fold increases in IL‐1β and IL‐6 were lowest for MPC while ISP and DWMP showed the greatest increase in IL‐1β and IL‐6, respectively (p<0.05). IL‐10 was similar in MFGM and MPC but MFGM was significantly higher than ISP and DWMP after LPS challenge. Dairy protein components appear to differentially influence cytokine response to LPS. Intact dairy protein (DWMP), appears least inflammatory in a normal gut, while specific milk protein fractions (MPC and MFGM) allow for an improved and more highly regulated immune response to LPS challenge.Grant Funding Source: National Dairy Council Project #1120 administered by Dairy Research Institute
Defining the role of pulse grains in cancer prevention (824.10)
Authors: Thompson Henry , McGinley John , Echeverria Dimas , Brick Mark 
Published: June 2021

Pulse crops, including dry beans, dry peas, chickpeas, and lentils, are grain legumes that serve as staple food crops for populations around the world. Since ancient times, pulses have been combined with cereal grains, primarily wheat, rice, or corn, or with tubers such as potato or cassava to provide a balanced source of protein and carbohydrate and a nutritionally adequate diet when combined with seed oils, fruit and vegetables. In this setting, the established ratio of cereal grains to pulses to meet nutritional requirements is 2:1; however, over the last 60 years both production and consumption patterns, globally, have changed to 8:1. One consequence of these changes has been a marked but largely unappreciated exclusion of pulse crops from the diet. In this study, the effects of one type of pulse crop, common bean, was evaluated in a dual model for experimentally induced colon and breast cancer in female Sprague Dawley rats injected with both 1‐methyl‐1‐nitrosourea and azoxymethane. Specific varieties of cooked, freeze‐dried bean were incorporated into a purified diet and fed during the post initiation phase of the disease process. Depending on common bean variety, the occurrence of both aberrant crypt foci in the colon and mammary carcinomas were inhibited when beans were included in the diet compared to the control without bean. Magnitudes of inhibition ranged from 25 to 50%. Potential contributions of various components of cooked bean are considered including content of fiber and various phytochemicals. The lack of significant amounts of common bean and other pulse grains in the US diet may represent an underexploited public health opportunity especially in the context of re‐establishing complementary patterns of consuming pulse grains and cereal crops.Grant Funding Source: PHS R01‐ CA172375
Hsp90 inhibition abolishes LPS‐mediated NF‐κB transcriptional activation independent of IKKβ in human lung microvascular endothelial cells (HLMVEC) (847.7)
Authors: Thangjam Gagan , Joshi Atul , Barabutis Nektarios , Charalampos Birmpas , Patel Vijay , Fulton David , Catravas John 
Published: June 2021

LPS promotes NF‐κB‐dependent inflammation by activating IKKβ which phosphorylates inhibitory IKB proteins leading to their degradation. Basally, NF‐κB exists in an inactive cytoplasmic complex with IKB. Stimulus‐dependent degradation of IKB allows NF‐κB to translocate into the nucleus and initiate transcription. Hsp90 is essential for the activation of a number of kinases, including IKKβ, and thus an important regulator of the NF‐κB pathway. Here we demonstrate that hsp90 inhibition by 17‐AAG attenuated LPS‐induced NF‐κB reporter and target gene activation in HLMVEC. Similarly, inhibition of upstream TAK‐1 and IKKβ blocked IKBα phosphorylation/degradation by LPS. However, 17‐AAG blocked the LPS‐induced phosphorylation/ubiquitination of IKBα without preventing its degradation. Indeed, in the presence of 17‐AAG, LPS degraded a phosphorylation/ubiquitination‐deficient mutant IKBα. This 17‐AAG‐mediated degradation did not involve IKKβ, since addition of excess IKKβ inhibitor, after 17‐AAG, failed to recover IKBα protein levels. Instead, 17‐AAG prevented the LPS‐induced recruitment of NF‐κB and its co‐activator CBP to NF‐κB target gene promoter. This was associated with the prevention of LPS‐induced core histone H3 eviction and N‐terminal phosphorylation of RNA polymerase II. Thus, we conclude that hsp90 inhibition does not affect IKKβ‐dependent NF‐κB signaling but blocks NF‐κB transcriptional activation via an epigenetic mechanism in HLMVEC.Grant Funding Source: HL093460
Cocaine‐induced locomotor sensitization persists in rats that escalate cocaine self‐administration in a short‐access procedure (848.6)
Authors: Mandt Bruce , Copenhagen Leland , Zahniser Nancy , Allen Richard 
Published: June 2021

The role of sensitization in cocaine addiction remains debatable. In rats, non‐contingent cocaine‐induced locomotor sensitization is well documented. However, the relationship between this measure and measures of cocaine self‐administration is less clear. For example, repeated non‐contingent cocaine pre‐exposure enhances acquisition of self‐administration and increases break points (BPs) for cocaine. Following escalation of intake or BPs, however, some studies report tolerance to cocaine’s locomotor‐stimulating effects. Importantly, sensitization is often assessed after long self‐administration histories or high levels of cocaine exposure. We have recently developed a method for assessing escalation early in self‐administration. Using this method, here we report on the relationship between cocaine‐induced locomotor sensitization and escalation early in the drug‐taking process. Cocaine‐induced (10 mg/kg, i.p.) locomotor activity was assessed on 3 occasions: 1) in a drug‐naïve state, 2) after 5 days of non‐contingent cocaine administered in operant chambers, and 3) 48 hrs after the 10th active self‐administration session. Once‐daily non‐contingent cocaine administration (0.8 mg/kg, i.v.) in the self‐administration context induced robust locomotor sensitization. When allowed to self‐administer cocaine (0.8 mg/kg, i.v.), rats rapidly escalated intake over 10 post‐acquisition sessions. Notably, cocaine‐induced locomotor sensitization was preserved following self‐administration, despite escalation. These data suggest cocaine‐induced locomotor sensitization and escalation are not mutually exclusive, but rather, may occur in tandem during the earliest stages of drug taking.Grant Funding Source: Supported by NIH Grant R01 DA004216
Estrogen signaling alterations in resistance arteries postpartum (849.6)
Authors: Royal Crista , White Richard 
Published: June 2021

Few studies have examined the after‐effects of childbirth on the female vasculature – especially the resistance microvasculature of non‐reproductive tissues, which are a major determinant of blood pressure. 17β‐estradiol (E2), an important vasoactive hormone, normally declines after parturition; however, many women artificially increase estrogen levels after pregnancy by taking oral contraceptives.Our hypothesis was that parturition attenuates E2‐induced relaxation in mesenteric arteries by decreasing nNOS expression. We measured a 73% decrease in serum E2 levels in the postpartum state compared to nulliparous Sprague‐Dawley rats. We found that microvessels from postpartum animals exhibited: 1) endothelium‐independent, E2‐induced relaxation (intact 18.78 ± 3.84% vs denuded 15.37 ± 3.30%), 2) impaired E2‐induced relaxation due to decreased NOS activity (L‐NMMA, ‐17.54 ± 15.66% vs postpartum controls 12.98 ± 2.94% relaxation at 1000nM E2), 3) impaired nNOS‐dependent, E2‐induced relaxation, and 4) decreased nNOS expression (down 39% p=0.0077). Because E2 has been shown to increase nNOS protein expression, we propose that lower E2 levels after parturition decrease expression of nNOS, leading to a reduced vasodilatory capacity of resistance microvessels.Grant Funding Source: Supported in part by NIH HL073890
Transport of high density lipoproteins though endothelial cells (855.7)
Authors: Perisa Damir , Käch Andres , von Eckardstein Arnold , Rohrer Lucia 
Published: June 2021

Atherosclerosis is a progressive accumulation of lipids in the arterial intima leading to plaque formation. Epidemiological studies show an inverse association of high density lipoprotein (HDL) cholesterol with cardiovascular events. HDL has multiple anti‐atherogenic functions, some of which take place in the vessel wall. To get access to the intima and the lipid‐laden macrophages, HDL has to pass the endothelial barrier.To elucidate the itinerary of HDL through endothelial cells (ECs), we investigated localisation and distribution of fluorescently and 1.4 nm Nanogold labelled HDL in fluorescent (FL) as well as electron microscopy (EM). For EM, we used high pressure freezing (HPF) and to avoid lipid extraction we developed a fast method for silver enhancement of the nanogold‐HDL after fixation in OsO4.HDL is detectable in ECs in a concentration and time dependent manner. Colocalisations of HDL with dextran were negative excluding fluid phase uptake and transferrin and albumin show only slight colocalisation indicating an atypical uptake mechanism.Further experiments showed that HDL is neither targeted to lysosomes nor to the Golgi or the endoplasmatic reticulum. Only small amounts can be detected in early endosomes (Rab5) and endosome to trans‐golgi network (Rab9), but not at all with late endosomes (Rab7), the recycling endosomes (Rab11a) or vesicles involved in trans‐Golgi network sorting (Stx6). EM ultrastructure shows HDL to be located mainly in multivesicular bodies.We corroborated our findings in aortic artery endothelium. Live microscopy experiments as well as biochemical data help us to understand the itinerary of HDL through aortic ECs.
Endogenous kappa opioid receptors play a role in angiotensin II high salt diet hypertensive rats (860.24)
Authors: Nguyen Tin , Franklin Cynthia , Hollister Bernadette , Tang Jeffrey , Rangel Yolanda , Gottlieb Helmut 
Published: June 2021

Central kappa opioid receptor (KOR) activation produces a marked increase in renal sympathetic nerve activity with a concurrent free water diuresis in conscious rats. However, the role of KOR in the angiotensin II high salt diet (AngII) mediated hypertension model is yet to be determined. This study examines cFOS expression in several brain regions of AngII rats as compared to normal rats. In addition, cFos expression in these brain regions was examined following intracerebroventricular (ICV) microinjection of norbinaltorphimine (Nor‐BNI; 1 μg/5μl), a selective KOR antagonist. Alternate sets of forebrain sections were processed for c‐Fos using a commercially available antibody. Sections were also double labeled with vasopressin to anatomically define specific brain regions. Fos expression was significantly increased in several lamina terminalis and hypothalamic sites. ICV nor‐BNI produced significant decreases in cFos staining in the PVN (AngII, 106 ± 12; nor‐BNI 62 ± 7; P < .01) and OVLT (AngII, 132 ± 7; nor‐BNI 73 ± 5; P < .05). There was no significant change in urine and sodium excretion in all groups. Altogether, this data provides new information concerning the role of KOR in the regulation of blood pressureGrant Funding Source: 5SC2HL104639‐03
Characterization of a cGMP‐dependent protein kinase I gamma nuclear localization sequence (866.2)
Authors: Chen Jingsi , Roberts Jesse 
Published: June 2021

PKGI regulates vascular smooth muscle cell (SMC) phenotype through incompletely understood mechanisms. Recently, we noted that cGMP stimulates PKGI proteolysis, in part by proprotein convertases, the nuclear localization of a constitutively active kinase fragment, PKGIγ, and transactivation of CRE‐dependent gene expression. PKGIγ appears to harbor an IL‐1α‐like NLS described by others (Gudi 1997). Here we tested whether this putative NLS determines PKGIγ compartmentation and function.We observed that a single amino acid mutation in PKGIγ was sufficient to modulate its nuclear localization. Immuno‐localization studies revealed that rat aortic SMC transfected with plasmids encoding PKGIγ with a KIL(K‐>E)KRH mutation exhibited decreased nuclear PKGIγ compartmentation. Moreover, studies using a plasmid‐encoded nuclear phospho‐CREB S133 biosensor (Friedrich 2010) and fluorescence lifetime imaging revealed that these cells had less nuclear PKGI kinase activity even though immunoblotting revealed preserved cytosolic enzyme activity. Moreover, the nuclear function of PKGIγ was not due to cAMP signaling system cross talk as it persisted in cells treated with myr‐PKI, a PKA inhibitor.These data indicate that a defined amino acid sequence regulates PKGIγ nuclear localization and function. Additional studies are warranted to test how this nuclear PKGIγ compartmentation regulates SMC phenotype.Grant Funding Source: Supported by NIH grant R01HL096779
Exposure of human bronchial epithelial cells to fungal aeroallergens induces calcium mobilization and anion secretion by a mechanism involving oxidative stress (869.3)
Authors: O'Grady Kelly , Maniak Peter , Kita Hirohito 
Published: June 2021

Aeroallergens produced by Alternaria alternata have been shown to induce life threatening exacerbations of airway inflammation in sensitized patients with severe asthma. Inflammation produced by Alternaria is associated with ATP release and purinergic receptor activation. In the present study the effects of Alternaria on signaling pathways and ion transport mechanisms associated with mucociliary clearance were investigated in an immortalized human bronchial epithelial cell line (16HBE14o‐ cells). Cells were grown on SnapwellTM membrane filters until a stable transepithelial resistance (>500 Ω) was established. Cell monolayers were then voltage clamped at zero mV and apically stimulated with 50 μM Alternaria extract to induce a time‐dependent increase in short circuit current (Isc) consistent with anion secretion. Treatment with the CFTR channel blocker, CFTRinh‐172 significantly reduced the Isc by ~25%. Furthermore, addition of the disulfonic stilbene compound DIDS (250 μM) abolished the Isc response. Measurements of the effect of Alternaria on intracellular Ca2+ concentration ([Ca2+]i) showed that the extract caused a persistent increase in [Ca2+]i that was blocked by chelating extracellular Ca2+ with EGTA. Pretreatment with 250 μM DIDS also abrogated the effects of Alternaria on [Ca2+]i but did not affect the increase in [Ca2+]i produced by 4 μM ionomycin. Similarly, pretreatment of monolayers with glutathione also blocked the Alternaria induced increase in [Ca2+]i. These results indicate that Alternaria aeroallergens are capable of stimulating CFTR and Ca2+‐dependent anion secretion. Moreover, the increase in [Ca2+]i appears to involve a DIDS‐sensitive uptake mechanism that is blocked when oxidant scavenger molecules are present in the extracellular solution.Grant Funding Source: Supported by NIH: HL110539
Aeroallergens derived from Alternaria alternata evoke ATP release and chronic increases in intracellular Ca2+ in bronchial epithelial cells by a mechanism involving oxidative stress (869.4)
Authors: Patil Nandadevi , Maniak Peter , Kita Hirohito , O'Grady Scott 
Published: June 2021

Alternaria aeroallergens have been previously shown to stimulate allergic inflammation and exacerbation of respiratory distress in patients with asthma. An early event following exposure to Alternaria extract is the sustained release of ATP and a persistent increase in intracellular [Ca2+] ([Ca2+]i) resulting from uptake of Ca2+ ions from the extracellular solution. In the present study we tested the hyopothesis that the release of ATP and the subsequent increase in [Ca2+]i was due to oxidative stress induced by exposure to Alternaria. ATP release following apical stimulation with Alternaria was measured in human primary bronchial epithelial cells using a luciferase/luciferin ATP measurement kit in combination with a modified luminometer that allows for tracking ATP release in real time. Pretreatment with glutathione (GSH) produced a concentration‐dependent inhibition of ATP release with an EC50 = 500 μM. Furthermore, GSH blocked the increase in [Ca2+]i typically observed following apical exposure to Alternaria. Moreover an increase in the expression of specific antioxidant protein mRNAs was also observed after 12 hours of treatment with Alternaria extract. These proteins included peroxiredoxins 1‐6, keratin 1, cyclooxygenase 2 (COX2) and oxidative stress responsive 1 protein with COX2 having the highest level of expression (~20 fold). These results implicate oxidative stress as an important initiating event in Alternaria evoked airway inflammation.Grant Funding Source: Supported by NIH: HL110539
Therapeutic effects of mesenchymal stem cells on hepatocellular carcinma: tracking of cells using iron oxide nanoparticles (87.3)
Authors: Noorwali Abdulwahab , Faidaah Mamdooh , Atta Hazem , Damiati Laila , Filimban Najlaa , Al‐Grigry Mihal , Habib Hamid , Radwi Amer , Almarees Ali 
Published: June 2021

Recently, a significant increase in the incidence of hepatocellular carcinoma (HCC) has been reported. However, early detection of the disease can help in selecting from various available therapies. Unfortunately, in advanced liver cancer cases, treatment options are very limited. In the present study, we point to the need to identify a new effective, less aggressive treatment approach. Advances in stem cell research, led us to consider cell‐based therapy for treating liver cancer.It was previously reported that bone marrow derived mesenchymal stem cells (MSCs) have the tumor suppressive effects in an experimental HCC model in rats. In this work, we investigated the possible role of Wnt signaling in hepatic carcinogenesis and how it is influenced by by MSCs labeled with iron oxide nanoparticles.Forty rats were used and were divided equally into four groups: a normal control group and 3 groups that received diethylnitroseamine and CCl4 to induce HCC. Then after induction, one group was treated with MSCs only, the second group with PBS (vehicle) only, and the third group with labeled MSCs with iron‐oxide nanoparticles. Gene expression of Wnt signaling target genes by reverse transcription‐polymerase chain reaction (RT‐PCR), in rat liver tissue, was measured. In addition, serum levels of liver function parameters and alpha fetoprotein were performed in all groups. Histopathological examination of the liver and organ samples from all groups was performed. Magnetic resonance imaging (MRI) was used to visualize MSCs loaded with iron oxide nanoparticles in the affected liver. We detected a significant tumor‐mass reduction in the group which received MSCs compared to the control groups.The results of this work confirm the previous finding of a possible therapeutic effect of MSCs on HCC. In addition, the use of iron oxide nanoparticles may prove to be successful in tracking and localizing MSCs to the site of the lesion, which may provide a documentation of their therapeutic effect.Grant Funding Source: Supported by grant from the Deanship of Scientific Research, King Abdulaziz University Jeddah, KSA
Both central and peripheral phrenic‐intercostal circuitry mediate respiratory recovery following cervical spinal cord injury (871.1)
Authors: Awad Basem , Warren Philippa , Alilain Warren 
Published: June 2021

The organization of the respiratory network has traditionally been described through descending medullary tracks. We have determined central and peripheral mechanisms auxiliary to the descending supraspinal pathways through which intercostal activity can augment breathing. Following lateral C2 hemisection (LC2Hx), functional recovery of the paralysed ipsilateral diaphragm is largely mediated through the crossed phrenic pathway (CPP). However, the contribution of the intercostals to this effect has not been determined. We show that LC2Hx results in paralysis of the ipsilateral intercostal muscles. However, contralateral phrenicotomy returns activity to both the paralyzed hemidiaphragm and intercostals. These exciting data demonstrate the presence of a crossed intercostal phenomenon acting in synchrony with the CPP. We demonstrate the further interconnectivity of phrenic and intercostal motoneurons across the spinal cord (SC) midline through intercostal‐phrenic ascending pathways. These pathways are necessary for hemidiaphragmatic recovery after LC2Hx. Together, these data are indicative of both descending and ascending bilateral crossed pathways to control respiratory motor activity following cervical trauma. Further to these central mechanisms, we provide evidence of an alternative monosynaptic peripheral pathway between the phrenic motor nucleus and the intercostal muscles, which can maintain intercostal respiratory activity following lower cervical SC transection. In conclusion, significant redundancy acts both centrally and peripherally to the cervical SC to mediate respiratory activity following trauma. These data strongly implicate the necessary role of intercostals in recovery of respiratory motor function following spinal cord injury, as well as alternative therapeutic targets.Grant Funding Source: Supported by Craig H. Neilsen Foundation and MetroHealth Medical Center