bluuebunny/crossref_metadata_2025_split huggingface dataset:
Early intestinal tight junction loss after hemorrhagic shock
Authors: Thuijls Geertje , de Haan Jacco‐Juri , Derikx Joep P , Bamburg Jim R , Heineman Erik , Buurman Wim A 
Published: June 2021

The intestinal barrier is based on tight junctions (TJ) between intact epithelial cells. These TJ are anchored via the filamentous (F‐)actin cytoskeleton. We hypothesize that hemorrhagic shock (HS) leading to intestinal hypoperfusion, causes loss of F‐actin, via activation of Actin Depolymerizing Factor/Cofilin (AC), and consequently results in TJ loss. This study investigates intestinal AC activation and cytoskeleton severing following HS.Rats were subjected to HS and sacrificed, along with controls, at 15, 30, 60 and 90 min after induction of shock. Intestinal hypoperfusion, activation of AC, actin cytoskeleton severing (degradation of F‐ into globular actin), and TJ integrity loss (Claudin‐3, ZO‐1) were assessed.HS caused intestinal hypoperfusion (−71.7% bloodflow) and activation of AC from 15 min after HS (by 21%, P<0.05 vs controls, student's t‐test (stt)). This was accompanied by actin cytoskeleton severing, followed by intestinal TJ loss from 30 min after HS (Claudin‐3: 100% vs 71%; ZO‐1: 100% vs 41%, p<0.05 vs controls, stt).We show for the first time that HS results rapidly in intestinal hypoperfusion, AC activation, actin depolymerization and subsequent TJ loss. Elucidation of the etiology of barrier failure is a first step in understanding the disease entity, which will be followed by the development of therapeutic interventions to reduce the development of barrier failure.
Normalization of proliferation and paracellular permeability of bladder epithelial cells from interstitial cystitis patients by a synthetic inhibitor of antiproliferative factor
Authors: Keay Susan , Kaczmarek Piotr , Zhang Chen‐Ou , Michejda Christopher 
Published: June 2021

Objectives: Interstitial cystitis (IC) is a chronic disorder with bladder epithelial thinning or ulceration, pain, urinary frequency and urgency. Bladder epithelial cells from IC patients make an antiproliferative factor (APF) that inhibits cell growth, decreases tight junctions, and increases paracellular permeability. We screened inactive synthetic APF derivatives for their ability to inhibit APF, then determined the ability of an inhibitory derivative to normalize proliferation and permeability of IC cells.Methods: Normal bladder cells were pretreated with inactive APF derivatives, then incubated with active synthetic APF. IC cells were incubated with varying concentrations of D‐proline APF. Cell proliferation was determined by 3H‐thymidine incorporation. Gene expression was determined by quantitative RT‐PCR. Paracellular permeability was determined by 14C mannitol and 3H‐inulin flux on Transwell plates.Results: One of 28 inactive derivatives (D‐proline APF) blocked APF activity in normal bladder cells. D‐proline APF also significantly increased cell proliferation, increased zonula occludens‐1 and claudin 1, 4 and 8 expression, and decreased permeability of IC cells.Conclusions: D‐proline APF can normalize IC cell proliferation and paracellular permeability in vitro, making it a potential therapy for IC. Supported by NIH R01 DK52596 and the Intramural Research Program of the NCI, NIH
Redox state and PKC signalling in neuronal differentiation and sensitivity to glycoxidative stress
Authors: Nitti Mariapaola , Furfaro AnnaLisa , Cevasco Claudia , Traverso Nicola , Marinari Umberto Maria , Pronzato Maria Adelaide , Domenicotti Cinzia 
Published: June 2021

Intracellular redox state modulation can influence cell proliferation, differentiation or death. Here we show that Retinoic Acid (RA)‐induced neuroblastoma cell differentiation is accompanied by increased expression of anion superoxide generating enzyme NADPH oxidase, decreased SOD1 expression and increased catalase expression. Moreover, cell differentiation induced PKC alfa inactivation and PKC delta activation. We believe these alterations responsible for the observed cell sensitivity to glycoxidative stress: indeed, only the RA‐differentiated cell viability decreased after exposure to Advanced Glycation End Products (AGEs), via intracellular ROS overproduction, while undifferentiated cells proved insensitive. AGE‐induced effects on differentiated cells were prevented by pre‐treating cells with NADPH oxidase or PKC delta inhibitors. These observations may be useful in order to identify redox sensitive molecular targets responsible for cell growing rate modifications.Grants from PRIN n.2006065711_002
Inihbition of Protein Glycation with Varying Concentrations of Lysine
Authors: Sims Heather M. , Birdwell Angela L. , O'Reilly Kelley E. , Bwashi Adonis , Wing Barbara D. 
Published: June 2021

The causes of the complications of diabetes mellitus have been explored in ongoing studies in our laboratory using an In Vitro system. This system is used to screen compounds for their ability to inhibit the glycation of proteins by sugars. Vascular damage seen in diabetic patients is impacted by such protein sugar interaction. During this study it was found that lysine is an effective inhibitor of glycation. The inhibition of glycation was studied using a spectrophotometric assay for glycoproteins. Studies indicated lysine as most effective as an inhibitor of glycation at a concentration of 100 μg/ml. Lower levels of inhibition were observed when a concentration of 500 μg/ml was used. When the concentration was lowered to 50 μg/ml and 200 μg/ml the results showed the inhibition of glycation was roughly equal at each respective concentration. Further research is being performed to find the actual concentration at which the lysine inhibition no longer performs efficiently. Preliminary results indicated that further investigation is needed to determine the mechanism of inhibition and the possible use of lysine in the treatment of diabetic patients.This research project was funded by the Smith‐Glynn‐Callaway Medical Foundation.
In vivo Experimental Restorative Dentistry Model. Preliminary Study.
Authors: Farinha Rodrigo , Moreno M. Helena , Carrilho Eunice 
Published: June 2021

An experimental model should comprise all aspects that can influence the pathology or the treatment tested. For restorative dentistry treatments, although all the recent achievements related mainly with the increasing use of adhesive techniques, the cavity design and the sound tissue preservation are crucial to the treatment's outcome.The advantage of using an in vivo experimental model is that we can reproduce all variables affecting the restoration, carrying to the laboratory the problems of the clinic for a better understanding and new solutions. To collect data that can be comparable and directly applicable to humans, we must create a situation as quite as similar to the clinical approach. Although there are too many different caries experimental models drawings to test the mechanism of action of fluoride and dentifrice formulations, or the carcinogenicity of foods or those which can be protective, none has been made to test the materials used on restorative dentistry.We propose an experimental in vivo model, which aims to be used to test caries cavities restorations. We propose two different cavity drawings to be used in dog's teeth.
Intestinal Inflammation and Seizure: understanding the role of TNF‐alpha in rat model
Authors: Prakash Ajay , MEDHI BIKASH , Avti Pramod Kumar , CHAKRABARTY AMITAVA , Khanduja Kishan Lal 
Published: June 2021

Objective: Present study was carried out to evaluate the role of TNF α and correlation between intestinal inflammation and PTZ induced seizure susceptibility in rat model.Methods and Materials: Rats were divided into 3 groups (n=6 in each group). Colitis was induced by single intra‐colonic administration of TNBS (20mg / 35% ethanol). Group I received ethanol (vehicle) intra colonic, Group II (TNBS), Group III (thalidomide 150mg/kg b. wt/d orally for 14 days after induction of colitis). After 14 days animals were sacrificed and colonic tissue was used for morphological score, histological score and different biochemical parameters (MPO, MDA, SOD, Catalase, GPx, TNF‐α in serum & brain).Results: Seizure susceptibility showed increase seizure score as well as reduction of onset of the seizure in the colitis group compared to control group. Thalidomide provided protection against TNBS‐induced colonic damage both histologically, morphologically and as evident in different biochemical parameters (MPO, MDA SOD, CAT, GPx, and TNF‐α in serum and brain) (p<0.001).Conclusion: Present study showed the increase seizure susceptibility following peripheral inflammation of colitis indicate correlations of colitis and seizure with role of TNF α. (Supported by PGIMER, Chandigarh, India)
Simvastatin (Zocor®), but not atorvastatin (Lipitor®) or lovastatin (Mevacor®), impairs G2/M cell cycle transit in myeloid cells
Authors: Henry Matthew K. , Stockton Sarah , Laughlin Ryan , Glisic Aleksandra , Giles Jennifer 
Published: June 2021

The inhibition of HMG‐CoA reductase with statin drugs such as simvastatin, atorvastatin, and lovastatin can disrupt cell survival and proliferation of multiple cell types. Therefore, statins alone or in combination with other agents present an interesting strategy for the treatment of hyper‐proliferative disorders. Here we are interested in the anti‐proliferative effects of the statins in myeloid cells. Myeloid cells require growth promoting cytokines, such as interleukin‐3, for cell proliferation. These cytokines mediate their activity through the activation of several signaling pathways. Previously, we have shown that signaling through Akt is important for efficient cell cycle transit in myeloid cells. Culturing myeloid cells in simvastatin, atorvastatin, or lovastatin disrupts cytokine‐dependent cell cycle transit through the G1 phase of the cell cycle. However, only treatment of cultures with simvastatin results in delayed transit through G2/M phases of the cell cycle. Additionally, only simvastatin decreases protein expression of Akt. Although the statins are effective at inhibiting HMG‐CoA reductase activity, they appear to have varying effects on cell cycle transit in myeloid cells. The characterization of unique pharmacological properties of statins may help identify new therapeutic strategies effective for the treatment of myeloproliferative diseases.(Iowa Science Foundation – #ISF‐07‐07)
Induction of cellular stress via the p38 MAPK pathway drives VELCADE® (bortezomib)‐induced apoptosis in esophageal squamous cell carcinoma cells
Authors: Lioni Mercedes Ines , Noma Kazuhiro , Herlyn Meenhard , Smalley Keiran 
Published: June 2021

Esophageal carcinoma is known to have a 5‐year survival rate of less than 20%. This shows a failure of current treatment regimens to provide patients with a significant life expectancy after diagnosis.In preliminary studies we used a novel three‐dimensional (3D) model, formed by esophageal squamous cell carcinoma (ESCC) cell aggregates embedded into collagen type I to allow growth and invasion within the 3D tissue like structure. Treatment with bortezomib, a proteasome inhibitor, was strongly growth inhibitory in both conventional and 3D settings. In a 3D reconstruction model of a primary esophageal tumor, TUNEL staining revealed the induction of apoptosis using 0.5uM of the drug. Induction of apoptosis proceeded through activation of caspase‐9 and ‐3, and was p53 independent. Animal experiments were performed using TE12 ESCC xenografts in NOD/SCID mice. Treated animals showed a bortezomib‐specific reduction of tumor size associated with decreased Ki67 staining and increased TUNEL positivity. Proteasome inhibitors are known to induce cellular stress. Treatment of the ESCC lines with bortezomib led to increased activity in both the p38 MAPK and JNK pathways. A role for p38 MAPK in bortezomib‐induced apoptosis was demonstrated by the ability of the p38 inhibitor SB230580 (10uM) to block the bortezomib‐induced cleavage of caspase‐3. Identical results were observed using selective knockdown of p38 MAPK using siRNA. Our investigation suggests that p38 MAPK induction could be a useful strategy for apoptosis induction when combined with bortezomib.Supported by the National Cancer Institute (grant P01‐CA098101)
Two fluoroquinolone‐bisphosphonate (BP) derivatives show similar binding affinity to calcium phosphate (CP) particles, but have different antibacterial activity
Authors: Buxton Thomas Brooks , Runner Royce R , Herczegh Pal , McPherson James C 
Published: June 2021

We previously demonstrated that osteoadsorptive BP conjugates of fluoroquinolones (E41, ciprofloxacin‐BP), carried on CP particles (μ‐sized Skelite™), packed into a traumatized bony defect, showed value in the treatment of rat tibial osteomyelitis (British J Surg, 2004;91:1192–1196). A Gatifloxacin‐BP conjugate (GB) was contrasted to E41 for activity against methicillin‐susceptible Staphylococcus aureus, and other pathogens. Minimum inhibitory concentration (MIC) and Mininum Bactericidal Concentrations (MBC) were determined. In vitro binding studies, holding levels of E41 and GB constant (2 μg/ml), while increasing levels of CP (nm‐sized NanOss™), were determined by measurement of fluoroquinolone‐BP associated fluorescence. GB showed greater MIC and MBC activity against several Gram‐positive and Gram‐negative pathogens, e.g., an 8‐fold difference with S. aureus (Table). Binding appeared to be saturable. Maximal binding was: E41, 89.7 % ± 4.74, vs. GB, 76.8 % ± 2.35 (p≤0.05). The dissociation constant was: E41, 1.35 × 10−8 mM (NanOss™), vs GB, 1.83 × 10−8 mM (p≤0.05).Versus E41, GB has (i) improved activity against bone‐pathogenic S. aureus, and other bacteria, and (ii) shows a similar binding affinity to NanOss™, used as a CP vehicle for topical drug delivery.
Lipid peroxidation in Tradescantia pallida: a new bioindicator response of air pollutants
Authors: Rhoden Claudia Ramos , Carneiro Maria Fernanda Hornos , Petry Marcelo Rafael , Oliveira Regiani Carvalho , Saldiva Paulo Hilário Nascimento 
Published: June 2021

Tradescantia pallida is a very common garden plant which is widely used as a bioindicator. The aim of this study was to test this plant as a model to detect oxidative damage as well as genotoxicity and accumulation of trace elements induced by vehicular emissions. Twenty vases of Tradescantia pallida were distributed into two sites: 1) rural area=control; 2) urban area, for 2 months during the winter. We evaluated the genotoxicity (by the frequency of micronuclei (MCN) in meiotic pollen mother cells), the accumulation of trace elements in leaves ( by X‐Ray Flourescence Analysis) and the oxidative damage (by malondialdehyde ‐MDA‐ concentration) in leaves. We found an increase of MCN frequency in the urban area site as compared with the rural area (%MCN – rural area = 0.73+/−0.49; urban area= 4.61+/−1.17; p<0.05) as well as an increase of MDA ([MDA]: micromol/fw ‐ rural area= 0.018+/−0.001 X urban area= 0.022+/−0.001; p=0.023). The rural area presented lower concentration of Br, Ca, Cl, Co, Mg, Mn, Mo, Pb, Sc and Zn as compared to the urban area. Our study showed that Tradescantia pallida serves both as a bioindicator of genotoxic substances as of oxidizing contaminants. In addition it is capable of accumulating trace elements in their leaf tissue.Support: CNPq, FFFCMPA, Secretaria da Saúde do Esatdo do Rio Grande do Sul ‐ Brazil
Elevated periarterial hydrogen peroxide in resistance vessels of spontaneously hypertensive rat (SHR) during rest and increased flow is reversed by apocynin
Authors: Zhou Xiaosun , Bohlen H Glenn , Miller Steven J , Unthank Joseph L 
Published: June 2021

Flow‐mediated dilation is mediated by H2O2 in humans with arterial disease. We have shown that NO does not increase with elevated flow in resistance arteries of SHR and aged rats. These same vessels do not enlarge as collaterals. We tested the hypothesis that flow‐mediated H2O2 is upregulated in SHR, and reversed by the NADPH oxidase inhibitor, apocynin. Our mesenteric model was used in young WKY rats, SHR and SHR pre‐treated with apocynin (Apo‐SHR). H2O2‐specific electrodes were used to measure real‐time, in vivo mesenteric periarterial [H2O2]. Specificity of electrodes was verified with catalase. After H2O2 baseline measurement, collateral flow was increased 50–200 % by clamping adjacent arteries. Baseline H2O2 was significantly increased in SHR compared with WKY (26.2 ± 6.8 vs. 7.2 ± 0.9 μM, p< 0.05) or Apo‐SHR (11.1 ± 3.2 μM). Successive increases in flow significantly increased periarterial [H2O2] in SHR from baseline (1 clamp, 46 ± 16 %, p<0.05; 2 clamps, 61 ± 11 %, p<0.05). Flow‐mediated [H2O2] increases were prevented in Apo‐SHR (−18 ± 5 %, 6 ± 23 %; 1 and 2 clamps respectively) and not observed in WKY. The results indicate that elevated baseline and flow‐mediated H2O2 production may originate from NADPH oxidase in SHR. Flow‐mediated H2O2 production may be a compensatory mechanism for vasodilation in SHR but may also be responsible for collateral growth impairment.Support: HL42898 and HL20605
Regulation of local angiotensin type 1b receptor (AT1bR) expression explains collateral growth impairment in spontaneously hypertensive rats (SHR) and restoration of collateral growth (CG) by captopril
Authors: Miller Steven J. , Zhou Xiaosun S. , Norton Laura E. , Murphy Michael P. , Dalsing Michael C. , Bohlen H. Glenn , Unthank Joseph L. 
Published: June 2021

The SHR is characterized by an activated RAS, increased oxidative stress, endothelial dysfunction and impaired CG. Oligonucleotide microarray analyses were performed with SHR and WKY to gain insight into the molecular basis of CG impairment. The results demonstrated a fundamental difference in the overall gene expression pattern in collateral arteries compared to same animal controls. Downregulated collateral genes included AT1bR and angiotensinogen (AGT) while p22phox was upregulated in SHR control arteries relative to WKY (2.14+/− 0.50 vs 0.93+/−0.10). RT‐PCR confirmed the suppression of AGT in SHR and WKY (56+/−29% and 40+/−9%) and of AT1bR in SHR (42+/−9%). However, the AT1bR was upregulated in WKY collaterals (302+/−70%). Pretreatment with captopril, which we have previously shown to restore CG (Miller, AJP‐Heart, 292:2007), restored flow‐mediated NO production as assessed by in vivo periarterial NO measurement, prevented AT1R downregulation in collaterals (174+/−61%), and decreased p22phox expression. Losartan had no effect in SHR but prevented CG in WKY. Apocynin restored CG in SHR and had no effect in WKY. The results indicate an essential role for the AT1R in CG and suggest that the transcriptional regulation of this molecule during CG is modulated by the balance between oxidative stress and nitric oxide.Support: HL42898 and HL20605.
Pulsatile laminar flow keeps the vascular endothelium in a quiescent state via the regulation of a Kruppel‐Like Factor 2 pathway
Authors: Young Angela Chien‐hsin , Li Yi‐Shuan Julie , Shyy John J , Chien Shu 
Published: June 2021

Vascular endothelial cells (ECs) along the straight part of the arterial tree are generally spared from atherosclerosis by maintaining a quiescent phenotype, thus being protected from EC activation and leukocyte adhesion. The objective of this study is to elucidate the role of Krüppel‐Like Factor 2 (KLF2), a transcription factor that inhibits cell proliferation, in the athero‐protective action of pulsatile laminar flow (PS), which has high shear stress and a large net forward direction that mimics the athero‐protective flow pattern in the straight vessels. We have previously shown that PS inhibits EC proliferation and can induce KLF2. In the current study, using BrdU incorporation and immunostaining, we showed that 24‐hr PS caused a significant reduction of cell proliferation rate to 2% in comparison to 20% in static cells. Knocking down KLF2 (to ∼50%) with siRNA reversed the PS‐reduction of cell proliferation rate up to 11%. These results indicate that the anti‐proliferative action of PS is mediated by KLF2. To elucidate the signaling upstream to KLF2, we found that blocking AMP‐activated protein kinase (AMPK) prevented PS‐induced KLF2 expression. Thus, PS causes an activation of KLF2 through AMPK. These results provide a mechanistic explanation for the athero‐protective action of PS flow via the AMPK‐KLF2 pathway.(This work is supported by Grant HL064382 and UC San Diego Cardiovascular Scholarship Award)
Shp2 Negatively Regulates Growth in Cardiac Myocytes by Controlling Focal Adhesion Kinase and the mTOR/S6 Kinase Pathways
Authors: Marin Talita M. , Clemente Carolina F.M.Z. , Picardi Paty K. , Pascoal Vinicius D.B. , Lopes‐Cendes Iscia T. , Saad Mario J.A. , Franchini Kleber G. 
Published: June 2021

AimFocal adhesion kinase (FAK) has been assigned a role in the cardiomyocyte hypertrophy. Herein, we investigated whether the Src homology 2 domain‐containing phosphotyrosine phosphatase (Shp2) control FAK activity and its effect on hypertrophy of cardiomyocytes.MethodsNeonatal rat ventricular myocytes (NRVMs) were stretched in silicone plates (1Hz, 10%). Phosphatase activity was assessed in the anti‐Shp2 immune complex and in samples of Shp2‐PTP domain. FAK/Shp2 association was detected by co‐immunoprecipitation. Shp2 was depleted with siRNA. Hypertrophy of NRVMs was assessed by morphometry and the expression of β‐myosin heavy chain (β‐MHC) transcripts with RT‐PCR.ResultsFAK was most non‐phosphorylated in non‐stretched NRVMS, coinciding with relatively high basal association with Shp2 and Shp2 tyrosine phosphatase activity. Cyclic stretch enhanced FAK phosphorylation at Tyr397 (2.3‐fold) and reduced its association with Shp2 (~85%) and the phosphatase activity of the anti‐Shp2 immune complex (~40%). Shp2‐PTP domain was shown to dephosphorylate FAK immunoprecipitated from NRVMs. Depletion of Shp2 by siRNA enhanced FAK phosphorylation in non‐stretched NRVMs (2.1‐fold). Depletion of Shp2 with siRNA increased ‐MHC transcript and induced hypertrophic morphology (3‐fold) in non‐stretched NRVMs. These effects were accompanied by increased p70S6 kinase phosphorylation at Thr389. Treatment with the FAK/Src pharmacological inhibitor PP2 or rapamycin abolished the hypertrophy induced by Shp2 silencing.ConclusionThese data indicate that Shp2 controls basal FAK activity in cardiac myocytes, acting as a counter‐regulatory mechanism to antagonize hypertrophy induced by FAK and mTOR/S6K pathways.
Roles of ARF1 and ARF6 in receptor mediated endocytosis of metal‐binding proteins and cadmium‐metallothionein‐1 (CdMT‐1) toxicity in kidney proximal tubule (PT) cells
Authors: Lee Wing‐Kee , Wolff Natascha A. , Abouhamed Marouan , Verroust Pierre J. , Thevenod Frank 
Published: June 2021

Filtered metal‐binding proteins, such as transferrin (Tf) or metallothionein‐1 (MT‐1), are apically endocytosed partly via megalin/cubulin in kidney PT where CdMT‐1 internalization causes apoptosis. Small GTPase ARF (ADP‐ribosylation factor) proteins regulate vesicular trafficking. We investigated roles of ARF1 and ARF6, which have been involved in secretory and endocytic pathways, respectively, following Tf, MT‐1 and CdMT‐1 uptake by PT cells. WKPT‐0293 Cl.2 cells derived from rat PT S1‐segment were transfected with hemagglutinin‐tagged wildtype (ARF‐WT) or dominant‐negative (ARF‐DN; ARF1‐T31N, ARF6‐T27N) forms of ARFs. Endogenous ARF1 co‐localized with Rab7 (late endo‐/lysosomal) whereas ARF6 with Rab5a and Rab11 (early and recycling endosomes). Live immunofluorescence staining of megalin showed less surface expression in ARF6‐T27N cells, but not in ARF1‐T31N. Fluorescent Tf mainly accumulated perinuclearly in late endo‐/lysosomes in ARF‐WT but was decreased and/or remained near the plasma membrane in ARF‐DN cells. Intracellular MT‐1 was also reduced in ARF‐DN cells. Moreover, CdMT‐1 toxicity was significantly attenuated in ARF1‐T31N (by 66.1 ± 16.6%, n = 10) or ARF6‐T27N (by 51.0 ± 12.0%, n = 9) cells, compared to respective ARF‐WT. The data support roles for ARF1 and ARF6 in endocytosis and trafficking of Tf/MT‐1 to endo‐/lysosomes and CdMT‐1 toxicity of PT cells.Funding: DFG TH 345/8‐1