bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of Epithelial sodium channel ENaC is regulated by posttranscriptional mechanisms
Authors: Perlewitz Andrea , Nafz Benno , Skalweit Angela , Fähling Michael , Persson Pontus Börje , Thiele Bernd Joachim 
Published: June 2021

Epithelial sodium channel ENaC is essential in the regulation of sodium homeostasis for instance in the distal nephron and is involved in physiological processes like blood pressure control. Functional ENaC channels consist of three autonomously expressed subunits a, b and g. Their expression has been studied so far especially on the transcriptional and posttranslational level.The aim of this study was to elucidate posttranscriptional mechanisms, in particular the role of untranslated regions (UTR) and their interaction with RNA‐binding proteins (RNA‐BP) for stability and translational efficiency of ENaC mRNAs. As a model we used kidney cell lines mpkCCD and HEK293 cultivated under the action of known regulators of ENaC expression, e.g. aldosterone and vasopressin. Regulative potential of UTRs was investigated by luciferase‐reportergene‐assays, RNA/protein interaction by UV‐crosslinking‐assays and identification and functional characterization of candidate RNA‐BPs by RNA‐affinity‐chromatography, MALDI‐TOF‐MS, polysome gradient analysis and co‐transfection experiments.Our results show that posttranscriptional mechanisms are involved in the regulation of all three subunits under hormonal stimulation, but in particular in gENaC.
TRPV1‐MEDIATED MODULATION OF SYNAPTIC INPUTS IN IDENTIFIED KIDNEY‐RELATED SYMPATHETIC PREMOTOR NEURONS IN THE ROSTRAL VENTROLATERAL MEDULLA
Authors: Derbenev Andrei , Stocker Sean D. , Smith Bret N. 
Published: June 2021

The central nervous system regulates arterial blood pressure (ABP), largely by controlling actions of the sympathetic nervous activity which includes control of kidney. Synaptic balance in the neurons of the rostral ventrolateral medulla (RVLM) is a critical component in the central pathways mediating sympathetic cardiovascular regulation. Transient receptor potential vanilloid type 1 (TRPV1) are expressed in the RVLM, but cellular effects of TRPV1 activation in the RVLM are not known. Whole‐cell patch‐clamp recordings in brainstem slices were used to characterize synaptic activity of kidney‐related RVLM neurons identified using the transynaptic retrograde viral vector PRV‐152 and to test the hypothesis that activation of TRPV1 enhances synaptic inputs to these neurons. Immunohistochemical studies showed that TRPV1 receptors are distributed through RVLM and colocalized with kidney‐related RVLM neurons. Kidney‐related RVLM neurons fired action‐potentials at rest and received abundant synaptic input that could be modulated by TRPV1 agonists. Application of the TRPV1 receptor agonist, capsaicin (1 μM), increased the frequency of spontaneous IPSCs from 1.6±0.6 Hz to 4.6±1 Hz and EPCSs from 4±0.4 to 8.7±1 Hz, respectively. Capsaicin also increased action‐potential frequency in kidney‐related sympathetic premotor RVLM neurons from 3.1±0.5 Hz to 6±0.6 Hz (p<0.05). Modulation of RVLM neurons by TRPV1 agonists represents a novel means of modulating ABP and, by inference, hypertension.Supported by AHA 0865395D and NIH HL091293‐01A1
A short‐term free‐fall landing enhances local bone formation without showing of woven bone
Authors: Lin Hsin‐Shih , Huang Tsang Hai , Yang Ai Lun , Mao Shih Wei , Tai Yuh Shiou , Yang Rong Sen 
Published: June 2021

ObjectiveThe purpose of this study was to investigate the effects of a mechanical loading course (free‐fall landing) on local bone metabolism.MethodsThirty‐two female Wistar rats (7‐week‐old) were randomly assigned into three groups, which were the L30 (n=11), L10 (n=11) and CON (n=10) groups. Animals of the L30 and L10 group underwent 5‐day free fall landing from a height of 40cm for 30 and 10 times per day, respectively. Landing ground reaction force (GRF) was recorded on day 1 and day 5. Methods of dynamic histology, tissue geometric and biomaterial measurements were performed on animals' ulnae. One‐way ANOVA was used for statistical analysis. When statistical significance was shown (p<0.05), pair‐wise comparisons were made using the Fisher's LSD method.ResultsIn dynamic histological analysis, no ulna revealed formation of woven bone in all animals. Periosteal as well as endosteal mineral apposition rate (MAR, μm/day) was significantly higher in L30 group as compared to the CON group. And, periosteal bone formation rate per unit of bone surface (BFR/BS, μm2/μm3/year) was significantly higher in the L10 and L30 groups.ConclusionsIn conclusion, a 5‐day free‐fall landing training produce a slight but significant higher bone formation on ulnae of female young rats. As compared with other mechanical loading models, this free‐fall landing revealed no signs of damages (no woven bone formation) to landing site and would be a more realistic model to mimic mechanical stimulus induced by various physical activities.Grant supported from the National Science Council (NSC‐94‐2314‐B‐006‐033, Taiwan).
The HAND and SANT Domains Regulate the In vitro and In vivo Activity of the ISW2 Chromatin Remodeling Complex
Authors: Hota Swetansu Kumar , Hemeryck Christine S , Pugh B Franklin , Bartholomew Blaine 
Published: June 2021

The catalytic subunit of ISW2 chromatin remodeling complex consists of the conserved DEXD/HELIC domain and HAND, SANT and SLIDE domain. The role of HAND and SANT domain were analyzed by specific deletion of the entire domain or mutation of key amino acid residues. HAND and SANT domain are found to be dispensable for ISW2 complex integrity and binding to nucleosomal substrate however are critical for efficient nucleosome remodeling. SANT domain was found to be required for efficient ATP hydrolysis and remodeling of equally spaced dinucleosomes. Deletion of HAND domain affected a subset Isw2 regulated genes; however, SANT domain affected a larger set of gene characteristic of a dominant negative phenotype. Further the role of these domains were investigated by mutating conserved ISWI specific, surface accessible basic amino acids, forming a basic path and predicted to interact with extranucleosomal DNA, to alanine. Multiple mutations in HAND or SANT domain did not affect complex assembly or binding but did affect the rate of nucleosome remodeling. In vivo de‐repression of transcription was observed at several Isw2 specific loci with either deletion or mutations in HAND or SANT domains. Consistently nucleosome position changes were observed upon domain deletion at STE6 promoter region indicating that conserved ISWI specific basic amino acid residues in these domains regulate ISW2 activity and gene expression through changes in nucleosome position.This work was supported by Public Health Service Grant GM70864
Histone acetylation modulates the binding and remodeling activity of two different SWI/SNF complexes
Authors: Chatterjee Nilanjana , Shogren‐Knaak Michael , Bartholomew Blaine 
Published: June 2021

The coordination of chromatin remodeling with chromatin modification is key to the regulation of chromatin structure and function. Recent studies implicated a functional link between histone acetylation and the SWI/SNF class of chromatin remodeling enzymes. This functional interplay is mediated via highly conserved acetyl‐lysine binding modules, the bromodomains. The presence of bromodomain (s) in SWI/SNF and RSC therefore strongly suggests that recognition of histone acetylation might play a major role in chromatin targeting and / or in their chromatin remodeling function. Here the nucleosome binding and remodeling activities of the two yeast SWI/SNF complexes were dissected out separately and the impact of histone tail acetylation on each of these processes was studied systematically. We show that histone H3 tail acetylation and not H4 augments nucleosome binding by actually enhancing the binding affinity of RSC and SWI/SNF complexes for nucleosomes. Further, H3 tail acetylation mediated enhanced binding of SWI/SNF mimics SWI/SNF recruitment by transcription activator Gal4‐VP16. Finally, kinetic analyses under saturating enzyme conditions revealed that rates of remodeling and ATP hydrolysis are both stimulated independent of nucleosome binding upon acetylation of H3 tails.Thus acetylation additionally modulates the catalytic activity of SWI/SNF complexes besides providing a unique recognition surface.This work was supported by Public Health Service grant GM 48413
Nuclear protein extraction from frozen porcine myocardium
Authors: Kuster Diederik , Merkus Daphne , Dekkers Dick , Duncker Dirk Jan , Verhoeven Adrie 
Published: June 2021

Extraction of nuclear proteins from cells or tissues is an important tool for studying gene regulation and the responsible transcription factors. Here we present a homogenization and fractionation protocol for the preparation of nuclear extracts from frozen porcine left ventricular (LV) tissue. This nuclear extraction procedure gave a highly reproducible protein yield (7.3 ± 0.3% of total protein; mean ± SE, n= 11), a six‐fold enrichment of the nuclear marker B23, and more than 40% recovery of B23. The nuclear extracts were essentially devoid of contamination with cytosolic, myofilament and histone proteins as shown by Western blotting. Using this nuclear extraction method we show that upon treatment of animals with the β‐adrenergic agonist dobutamine, the amount of tyrosine phosphorylated STAT3 increased 6.9 ± 2.1 fold (n = 4, P = 0.03) in nuclear extracts from LV tissue, but only a minor fraction of the total PY‐STAT3 appeared in the nucleus. This nuclear extraction method appears to be well‐suited to nuclear proteome analysis of frozen heart tissue collected in biobanks.This work was supported by a grant from the Netherlands Heart Foundation (NHS2005B234).
Proliferation of pulmonary smooth muscle cells is stimulated by lung microvascular endothelial cells exposure to hypoxia via JAKs/STATs pathway
Authors: Wang Guansong , Wang Changzheng , Qian Guisheng , Yang Yu , Li Shujun , Zhang Zhiyuan 
Published: June 2021

RationaleIt is well known that hypoxia can regulate the proliferation and Apoptosis of many kinds of pulmonary cells, the effect of lung microvascular endothelial cells (LMVECs) on pulmonary arterial smooth muscle cells (PASMCs), and the related mechanism of signal transduction is unclear.ObjectiveTo investigate the effect of hypoxic LMVECs on PASMCs growth and the related signal pathway.MethodsRat LMVECs were randomly divided into 3 groups: normal group (N), 8 h hypoxia (H8), and 8 h hypoxia plus SU5416(H8+SU). Rat PASMCs were cultured with LMVECs medium from N, H8 and H8+SU. The gene expression of VEGF and TGFβ1 were detected with real‐time PCR. The protein levels of VEGF and TGFβ1 in their supernatant were detected with ELISA. The phophorylation of JAK2 and STAT3 was detected with Western blotting or EMSA.Results1. PASMCs proliferation was stimulated by hypoxic LMVECs medium. 2. VEGF and TGFβ1 mRNA and protein levels was increased in hypoxic medium. 3. The phosphorylation of JAK2 and STAT3 was activated in PASMCs cultured with hypoxic medium. 4. TGFβ1 neutralizing antibodies added to hypoxic medium could decrease the expression of p‐JAK2 and p‐STAT3, and suppress PASMCs proliferation. On the other hand, the growth of PASMCs was repressed during the phosphorylation of STAT3 was inhibited by AG490 and STAT3 inhibitor peptide.ConclusionGrowth factors, especially TGFβ1, released from LMVECs exposure to hypoxia activate cocultured PASMCs proliferation through JAK2‐STAT3 pathway.This abstract is funded by NSFC No.30770928, 973 Program No.2006CB504100, PLA grant No.06G083, and TMMU grant 2006HG04.
Proteomic Profiling of the Normal Human Mitral Valve
Authors: Suri Rakesh Mark , Srinivasan Manivannan , Abdul Rahiman Abdul Jaleel , Schaff Hartzell V. , Nair K. S. 
Published: June 2021

BackgroundStructural and functional mitral valve abnormalities are commonly encountered in the general population. In order to determine which functional protein classes may be important to normal valve function we performed the first reported comprehensive proteomic profiling of structurally normal human mitral valves.MethodsWe harvested mitral valve leaflets from 5 patients who underwent orthotopic cardiac transplantation for cardiomyopathy. The morphologic appearance of mitral valves was normal with only mild functional mitral regurgitation on echocardiogram. High resolution 2D gel electrophoresis was performed to separate proteins. Gel spots were excised from 2 representative samples and protein identification was carried out using liquid chromatography tandem mass spectrometry.ResultsWe identified 190 unique proteins with >99% probability and at least 2 unique peptides. The proteins were from various cellular locations, including cell surface, cytoskeleton, endoplasmic reticulum, extracellular matrix, mitochondrion, nucleus, cytoplasm, and plasma membrane. Functional clustering revealed that the identified proteins were involved in major molecular pathways including, energy along with fatty acid metabolism, calcium signaling acute phase response & oxidative stress, and anti‐apoptosis pathways.ConclusionProteomic profiling of the normal human mitral valve demonstrates a pattern of expression suggesting multiple biological functions. Further quantification of protein levels and comparison with diseased mitral valves will provide new insights into the etiology and therapy of mitral valve disease in humans.
Antifibrillatory actions of HBI‐3000 in the conscious canine model of sudden cardiac death
Authors: Lee Jullia , Lucchesi Benedict R 
Published: June 2021

The antifibrillatory actions of HBI‐3000 (sulcardine sulfate) were studied in a conscious canine model of sudden cardiac death (SCD). Female purpose‐bred beagles were anesthetized, and left ventricular anterior wall ischemic injury was induced by a 90 minute occlusion followed by reperfusion of the left anterior descending coronary artery. Three to seven days later, the dogs were randomized into two groups: Group 1 (n = 8) received 0.9% NaCl solution for injection while Group 2 (n = 7) received 15 mg/kg of HBI‐3000 intravenously. The dogs were subjected to anodal current‐induced injury of the circumflex coronary artery, resulting in transient interruptions in coronary artery blood flow and posterolateral myocardial ischemia. The electrocardiogram confirmed the presence of regional myocardial ischemia and ventricular fibrillation (VF). Control animals developed premature ventricular complexes (PVC) followed by ventricular tachycardia, which terminated in VF in four of the eight dogs and one expired overnight. PVC was also observed in HBI‐3000 treated animals, but only one of the seven animals developed VF in SCD (p < 0.05 vs. control). The data indicate that HBI‐3000 is effective in reversing polymorphic ventricular arrhythmias and has favorable antifibrillatory actions in the post‐infarcted canine heart subjected to a remote ischemic event.Supported by HUYA Bioscience International.
Platelet Activity In Elevated Plasma Seretonin Level
Authors: Ziu Endrit , Kilic Fusun 
Published: June 2021

The serotonin transporter (SERT) on the platelet surface is the major mechanism for the uptake of plasma serotonin (5‐hydroxytryptamine; 5HT), which subsequently is stored in platelet dense granules. The 5HT uptake capacity of the platelets depends on the number of SERT molecules on the plasma membrane.Our earlier studies demonstrated the presence of a dynamic relationship between plasma 5HT elevation, loss of surface SERT, and depletion of platelet 5HT. However it is not clear whether decreased SERT density on the platelet plasma membrane is a cause or consequence of increased plasma 5HT levels.In the current study, we addressed this issue by using two model systems: (a) 5HT‐pretreated platelets isolated from untreated C57BL/6J mice, and (b) platelets isolated from C57BL/6J mice in which plasma 5HT was elevated chronically by osmotic minipump. Our data in both model systems show a profound loss of surface SERT expression in platelets, depletion of platelet 5HT content and enhanced aggregation response to fibrillar collagen, demonstrating that 5HT‐depleted platelets appear to aggregate more readily. Furthermore, the aggregation rate of platelet is rescued by blocking the uptake ability of platelet SERT with serotonin reuptake inhibitor (SSRI), SERT blocker. These studies explicitly indicated that SERT down‐regulation by high extracellular 5HT in isolated platelets occurs in vivo and impacts platelet function against further aggregation in a protective feedback mechanism.Overall, these studies addressed that the intracellular 5HT concentration has a significant role in promoting hypercoagulation than the plasma 5HT‐level. The importance of understanding the structure, function, and regulation of SERT is underscored by the observations that plasma 5HT is elevated in the plasma, either locally or globally, during atherosclerosis, hypertension, stroke, and other cardiovascular diseases.
G219A polymorphism in CRP gene and occurrence of atrial fibrilation after cardiac surgery
Authors: Lavandero Sergio , Roldan Juan , del Campo Andrea , Verdejo Hugo , Garcia Lorena , Becerra Elia , Pinto Melissa , Navarro Mario , Solis Margarita , Corbalan Ramon , Mellado Rosemarie , Prat Hernán 
Published: June 2021

Atrial fibrillation (AF) is prevalent arrhythmia in adult population. Inflammation is a risk factor for AF and might have important in its occurrence. Increased C‐reactive protein plasma levels (CRP) have been found in AF and they could be determined by polymorphisms in the CRP gene. We investigate here if the G219A polymorphism in CRP gene is associated to AF occurrence. In this study, 116 patients with elective CABG were included. Systemic inflammatory markers were measured at baseline and 72 h after surgery. G219A polymorphism in the CRP gene, located 219‐bp downstream of exon 2 in the 3′ flanking sequence, was determined by PCR and we correlated with plasma CPR levels and AF occurrence. This study was approved by the Ethics Committee of each participating health center. All patient gave signed an informed consent. Mean age of patients was 61±11 years and 85% of them were male and 48% had a history of hypertension. Allelic frequencies for allele G and A were 0.57 and 0.43, respectively. There were no differences between genotypes with regard to diagnosis, risk factors, smoking, medical history and medications at entry. Postoperative FA incidence was 13%. Mean preoperative and postoperative PCR levels were 3.35 and 75.6 mg/L, respectively. We concluded that no association between G219A polymorphism in the CRP gene, CRP levels and AF were found.DI‐06‐09‐2, FONDECYT 1070641
S‐allylcysteine modulates the expression of E‐cadherin and inhibits the malignant progression of human oral cancer
Authors: Tang Feng‐Yao , Lin Meng‐Qiu , Cho Hsin‐Ju 
Published: June 2021

Oral cancer is a prevalent type of cancer in the Asian countries. Several studies indicated that garlic extracts such as diallyl disulfide (DADS) and diallyl trisulfide (DATS) have anti‐cancer effects. However, the inhibitory effects of water soluble garlic extracts, S‐allylcysteine (SAC), on the tumor malignancy of oral cancer have not been studied well yet. Thus, the purpose of this study was to investigate the inhibitory effects of SAC on the proliferation and progression of human oral squamous cancer CAL‐27 cells.In the present study, we demonstrated that SAC dose dependently inhibited the growth of human oral squamous cancer cells. Our results showed that SAC induced the expression of E‐cadherin adhesion molecule. Immunocytochemical staining result also revealed that SAC could restore the distribution of E‐cadherin molecule on cell membrane. We further demonstrated that SAC stabilized the adherent junction complex of E‐cadherin/β‐catenin in oral cancer cells. Treatment of MAPK/MEK specific inhibitor, PD098059, could upregulate the expression of E‐cadherin molecule. Furthermore, SAC significantly inhibited the activation of MAPK/ERK signaling pathway. These findings were associated with the down regulation of Slug repressor protein.In conclusion, our results indicated that SAC effectively inhibited the proliferation, upregulated the expression of E‐cadherin molecule, and stabilized the E‐cadherin/β‐catenin adherent junction complex in human oral squamous cancer cells. The mechanism of action was in part through the suppression of MAPK/ERK signaling pathway and downregulation of Slug repressor protein.
Novel expression and modification of the cytoskeletal protein Myozenin during hypertrophic growth
Authors: Paulsson Anna Kristina , Warburton Sarah , Mitchell‐Jordan Scherise A , Ren Shuxun , Wang Yibin , Vondriska Thomas M 
Published: June 2021

Cardiovascular disease is the leading cause of death in the developed world and includes growth of the heart (hypertrophy) resulting from altered mechanical and neural/hormonal factors. As a major clinical problem resultant from atherosclerosis and heart attacks, novel insights into hypertrophy are needed, in particular regarding changes in the diseased nuclear and cytoskeletal proteomes. To this end, transverse aortic constriction (TAC) was performed to induce pressure overload hypertrophy in mice. Hearts were excised between 1‐8 weeks post‐TAC, nuclei isolated and proteins separated by 2D or 1D PAGE and subjected to LC/MS/MS. Of ~1000 nuclear proteins exhibiting reproducible changes in abundance (p>0.05) after pressure overload, myozenin‐a molecular link between the phosphatase calcineurin and the structural protein α‐actinin‐was found to be upregulated. Further analysis of myozenin via immunoblotting and MS/MS revealed a truncated form that appears during hypertrophy. In addition, novel phosphorylation of residues S106, S116, T107 and T111 on myozenin‐2 was observed. Comparison of apparent mass using electrophoresis, immunoblotting and MS peptide maps revealed regions of modification on myozenin following injury. These studies add a new dimension to the role of myozenin in the heart and provide insights into nuclear‐cytoskeletal communication during cardiac hypertrophy.Support: NIH, AHA
Moderate increases in plasma cholesterol blunt the inflammatory response to salt‐induced hypertension
Authors: Rodrigues Stephen , Granger D. Neil 
Published: June 2021

Although an increased leukocyte and platelet adhesion is observed in cerebral venules of mice with either hypertension (HTN) or hypercholesterolemia (HCh), it remains unclear whether the combination of HTN and HCh exerts a comparable effect on leukocyte and platelet recruitment in the cerebral microvasculature. We examined whether HCh alters platelet and leukocyte adhesion in cerebral venules of hypertensive mice. A 50 mg DOCA pellet was implanted s.c. in uninephrectomized C57Bl/6 mice placed on 1 % saline for a period of 3 weeks. A 3‐week HCh diet did not alter blood pressure either alone or in combination with HTN. Donor platelets labeled with CSFE were administered i.v., along with rhodamine, for in vivo observation of platelets and leukocytes using intravital microscopy. The HTN‐induced recruitment of adherent leukocytes in cerebral venules was blunted by the presence of HCh. Platelet adhesion was unaffected by either HTN, HCh or a combination thereof. The role of HDL cholesterol in the leukocyte adhesion response was assessed using human apolipoprotein A‐I transgenic mice (TGApoA1). No significant differences in leukocyte adhesion were observed between TGApoA1 mice ± HTN. Our findings indicate that moderate increases in total plasma cholesterol blunt the pro‐inflammatory phenotype that is induced in brain by DOCA‐salt HTN.

Group
BP (mmHg)
Plasma Total Cholest. (mg/dL)
HDL (mg/dL)
Leukocyte Adhesion (per mm2)

Sham
104±2
70±3
40±4
29±12

HCh
104±1
111±11*
64±6
67±24

HTN
138±2*
85±5
55±2
129±15*

HTN/HCh
140±3*
120±7*
77±6*
72±9

TGApoA1
100±2
175±9*
148±1*
60±15

Sham

HTN
118±5*#
258±9*#
212±9*#
110±16*

TGApoA1

P<0.05 vs Sham,
P < 0.05 vs TGApoA1 Sham. (Supported by HL26441).