bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blunting of Endothelium Dependent Dilation in Adipose Tissue Arteries by Tumor Necrosis Factor Alpha is Lost after High Fat Feeding
Authors: McCullagh Joseph P , Henson Grant D. , Donato Anthony J. , Lesniewski Lisa A. 
Published: June 2021

Tumor necrosis factor alpha (TNF) is implicated in metabolic and endothelial dysfunction with obesity and aging. Although adipose tissue blood flow is reduced with obesity, the cause and consequences on lipid handling and systemic insulin sensitivity are not known. Impaired endothelial function in the resistance arteries of the white adipose tissue (WAT) per se may play a role. We determined if TNF impairs endothelium dependent dilation (EDD) in WAT resistance arteries of young normal chow (Y NC: 4–7 mo) fed mice and if this effect is lost in arteries from Y high fat (Y HF: 8–10 weeks) and old (O NC: 28–31 mo) fed B6D2F1 mice. Maximal EDD to acetylcholine was lower in WAT arteries from both Y HF (68 ± 8%, P<0.01) and O NC (82 ± 6%, P<0.01) vs Y NC mice (95 ± 2%). Recombinant TNF (1 ng/ml, 60 min) reduced EDD in WAT arteries from Y (69 ± 10%, P<0.01) and O NC (47 ± 4%, P<0.01), but not Y HF (65 ± 0.1%) mice. Endothelium independent dilation to sodium nitroprusside did not differ between groups (ALL P>0.05). Compared to Y NC (9.4 ± 1.1 pg/ml), WAT TNF concentration was increased in Y HF (17 ± 3, P<0.01) but not in O NC (11 ± 2) mice. Although these results suggest that previous exposure to excessive TNF in vivo may be responsible for impaired EDD in WAT arteries after HF feeding but not aging, it remains to be determined if endothelial dysfunction in WAT arteries contributes to diminished WAT blood flow and subsequently to inappropriate lipid storage and systemic metabolic/vascular derangements.Support: NIA‐AG033196, NIA‐AG033755
Novel aspects of leukocyte trafficking
Authors: gavins felicity , hughes ellen , buckingham julia 
Published: June 2021

The inflammatory response to the Toll‐like receptor (TLR) 4 ligand lipopolysaccharide (LPS) involves a sequence of intravascular leukocyte capture, rolling and adhesion, followed by their emigration into surrounding tissue which is accompanied by plasma protein extravasation (PPE). Typically, such events are observed hours after LPS injection, but we have chosen to investigate the earlier stages of leukocyte trafficking during murine experimental endotoxaemia.Using intravital microscopy of the mesentery, we observed a rapid increase in neutrophil emigration and PPE after i.p. LPS injection, reaching a plateau after 2h. The same response was seen with the TLR2 ligand zymosan, but not the non‐specific neutrophil activator ammonium thioglycolate, implicating TLR‐specific mechanisms in early leukocyte trafficking. LPS‐induced trafficking was associated with activation of peritoneal mast cells, shown by selective uptake of the dye ruthenium red from the superfusion buffer, and was inhibited by pre‐treatment with cromolyn sodium.To conclude, our data suggest that mast cells play a role in LPS‐induced peritoneal inflammation in terms of leukocyte emigration. Further work is underway to determine the sequential mechanisms of cell types and mediators involved in these hyperacute stages of LPS‐induced inflammation.Work supported by the BBSRC.
Effects of fluids on the liver microcirculation and cell free DNA in sepsis
Authors: Patrick Amanda L , Dwivedi Dhruva , Liaw Patricia , Fox-Robichaud Alison E 
Published: June 2021

Fluid resuscitation is a crucial therapy for sepsis. The release of DNA into the circulation in sepsis may predict mortality. Our objective was to determine if our fluids alter hepatic leukocyte recruitment or the levels of plasma cell free DNA (cfDNA).Cecal ligation and perforation (CLP) was used to induce sepsis in C57BL/6 mice, and compared to sham‐operated controls. Briefly, the cecum was ligated distally, punctured and returned post fecal extrusion. The right jugular vein was catheterized to deliver Seplyte L (SepL) and Seplyte H (SepH), and with or without albumin. Hepatic leukocyte recruitment was assessed by intravital microscopy and plasma cfDNA measured.CLP mice had higher leukocyte adhesion in sinusoidal and post‐sinusoidal venules compared to shams in all groups. Post‐sinusoidal adhesion was reduced in CLP mice given colloidal SepL and SepH vs. base solutions (13.6± 0.8 vs. 8.1±1.4 and 13.4±1.1 vs. 7.6 ± 0.6; p < 0.05). Six hrs post‐CLP, cfDNA was higher in septic mice when given SepL (9.2±0.3 vs. 4.9±0.5 μg/mL), SepH (8.6±1.4 vs. 4.9±0.4), SepL albumin (9.4±1.1 vs. 5.3±0.2) and SepH albumin (7.2±0.7 vs. 5.3±0.3) (p < 0.03). There was no difference in cfDNA between solutions.The addition of a colloid to fluids results in less systemic inflammation in early sepsis as measured by hepatic leukocyte recruitment. The production of cfDNA in early sepsis however is not altered by the presence of colloid.
Structural microvascular changes as a consequence of cyclophosphamide induced heart failure in rabbits
Authors: van Lier Monique GJTB , Milstein Dan MJ , Coronel Ruben , Spaan Jos AE , Siebes Maria , van den Wijngaard Jeroen PHM 
Published: June 2021

BackgroundCytostatic drugs are effective in cancer treatment but some have significant cardiotoxic side effects, including heart failure (HF). The aim of this study was to investigate the effect of high‐dose cyclophosphamide (CTX) on fiber and microvasculature (MV) structure of the heart.MethodsEight male New Zealand White rabbits (2.9 ± 0.1 kg) were randomly allocated into two groups receiving either 70 mg/kg of CTX (n=4) or sterile 0.9% NaCl (n=4; control) iv once a week for three weeks. Hearts were harvested one week after the last treatment, weighted, and the coronary arterial tree filled with fluorescent casting resin for structural analysis applying our imaging cryomicrotome.ResultsThe heart mass of CTX treated rabbits was significantly lower than normal (13.8 ± 0.4 vs. 17.1 ± 0.5; p = 0.04). All hearts were prepared for imaging; however, currently only 1 control and 1 CTX heart has been imaged. Consistent with the loss in heart mass, the preliminary results from the CTX heart showed ventricular dilatation and severe thinning of the ventricle walls. Heart fibers are normally densely arranged; however, the CTX heart consisted of loosely arranged fibers. Also, large transmural vessels are normally radially oriented, a characteristic lost in the CTX heart.ConclusionsCTX induces HF resulting in loss of fiber and MV structural organization.Supported by ZonMw 916.11.171
NG2 inhibition decreases endothelial cell sprouting along venules: A novel in situ angiogenesis assay to investigate multicellular interactions
Authors: Stapor Peter Conrad , Ahsan Taby , Murfee Walter Lee 
Published: June 2021

Elucidating the multicellular dynamics associated with angiogenesis requires the ability to examine mechanistic responses over the hierarchy of a microvascular network within a controlled environment. The objective of this study was to establish a simple in situ rat mesentery culture model to investigate pericyte‐endothelial interactions during angiogenesis in intact networks. Adult Wistar rat mesenteric windows were aseptically harvested and cultured in minimum essential media for 3 days. Media was left unstimulated or supplemented with bFGF, VEGF or bFGF + NG2 antibody. In supplement‐free media, viability/cytotoxicity analysis revealed that cells were alive after 3 days of culture. Immunohistochemical labeling with antibodies to PECAM, NG2 and LYVE‐1 identified endothelial cells, pericytes and lymphatic cells, respectively. VEGF and bFGF treatments stimulated approximately a 2‐fold increase in capillary sprouting, quantified as endothelial cell sprouts per venule length. NG2 function‐blocking antibodies inhibited the bFGF‐induced sprouting along venules. The results establish primary culture of the adult rat mesentery as a novel in situ angiogenesis model for investigating multicellular angiogenic mechanisms across intact microvascular networks, and implicate pericyte NG2 expression as a functional regulator of capillary sprouting. Supported by the Board of Regents of the State of Louisiana LEQSF(2009‐12)‐RD‐A‐19.Grant Funding Source : Supported by the Board of Regents of the State of Louisiana LEQSF(2009‐12)‐RD‐A‐19.
Accelerated Arteriogenesis In Collateral Arterial Segments Exposed To Flow Reversal After Femoral Arterial Ligation
Authors: Meisner Joshua K , Sumer Suna , Niu Jacqueline , Song Ji , Price Richard J 
Published: June 2021

Elevated fluid shear stress is known to be a key stimulus for driving arteriogenesis; however, the role that flow‐reversal (FR) plays in arteriogenesis is largely unknown. We hypothesized that FR in spatially distinct regions of collateral arteries (CAs) can lead to spatially distinct variations in CA growth.METHODSUnilateral femoral artery ligation (FAL) was performed in C57Bl6 mice. Gracilis muscles were harvested at 1, 7, 14, and 28 days after FAL and immunolabeled for smooth muscle α‐actin to visualize CAs. As determined by intravital microscopy, FAL increased flow across the length of the primary gracilis CAs with distinct regions of flow reversal (FR) and non‐flow reversal (NFR).RESULTSBoth FR and NFR CA segments showed significant growth as compared to the unligated (control) leg arterial diameters at days 7, 14, and 28 (p<0.001). However, CA regions experiencing FR showed significantly greater expansion of lumenal diameter (arteriogenesis) compared to the NFR regions at days 7 and 14 (p<0.005). This increase became non‐significant by day 28. At day 7, CD45+ leukocyte density was significantly greater around FR CA segments as compared to NFR segments (6.3±3.9 versus 3.9±2.1 CD45+ cells/collaterals, p<0.05, respectively). Further, pericollateral CD45+ cell density significantly correlated with CA diameter in ligated (R2=0.41, p<0.05), but not in unligated CAs (R2=0.0024, p=0.64).CONCLUSIONSThese data suggest that there are spatial variations in CA growth, CD45+ cell recruitment, and changes in hemodynamics along the length of a given CA after FAL. Together, our data suggest differences in mechanotransduction along a CA lead to differentialgrowth, with increased leukocyte accumulation as a potential mechanism. Supported by NIH HL074082, NIH R21HL098632, AHA 09PRE2060385, AHA 10GRNT3490001.
Perivascular cell dynamics during wrapping‐and‐tapping anastomosis
Authors: Liao Shan , Bazou Despina , Cheng Gang , Munn Lance L. 
Published: June 2021

Rapid blood perfusion is critical for post‐implantation survival of thick, prevascularized grafts or bioartificial tissues. In an earlier study, we showed that implanted vascular networks anastomose with host vessels through a process of “wrapping and tapping” between the engrafted endothelial cells (ECs) and the host vasculature. At the host‐implant interface, implanted ECs wrap around nearby host vessels, cause vessel wall reorganization and displace the underlying host endothelium, diverting blood flow to the implanted vascular network. The process is facilitated by high levels of matrix metalloproteinase‐14 and matrix metalloproteinase‐9 produced by the wrapping ECs.During this process, most host vessels within the brain and implant are fortified with NG‐2‐positive pericytes. In contrast, desmin‐positive pericytes are associated with mature vessels, but not angiogenic host vessels in the gel. Surprisingly, aSMA‐positive perivascular cells are not only associated with large, mature vessels in the brain, but also with the developing HUVEC plexus and wrapped host segments. Thus, aSMA positive stromal cells are involved in formation of the nascent network and desmin staining is associated with of the maturation of the engraft vessels.
Mitochondrial Function and Superoxide Production is Reduced in the Diabetic Kidney and Restored by AMPK Activation
Authors: You Young Hyun , Dugan Laura L , Naviaux Robert K , Sharma Kumar 
Published: June 2021

Diabetic microvascular complications are considered to be mediated by a glucosedriven increase of mitochondrial superoxide anions. Here we report that superoxide production was reduced in the type 1 diabetic mouse kidney, as assessed by in vivo real‐time transcutaneous fluorescence, confocal microscopy and electron paramagnetic resonance analysis. Mitochondrial biogenesis was reduced with diabetes while pyruvate dehydrogenase (PDH) was phosphorylated, consistent with an overall reduction in mitochondrial glucose oxidation. Mitochondrial biogenesis, PDH activity and mitochondrial complex activity were rescued by the AMPK activator 5‐aminoimidazole‐4‐carboxamide‐1‐β‐D‐ribofuranoside (AICAR) in both the streptozotocin (STZ) and Akita (Ins2+/C96Y) mouse models of type 1 diabetes. AICAR‐induced superoxide production in the diabetic kidney coincided with reduction of glomerular matrix and albuminuria. Furthermore, AMPKα2 −/− mice were found to have increased albuminuria and AMPK activity was reduced in human diabetic kidney disease. Taken together, the present results demonstrate that diabetic kidneys have reduced superoxide production, and AMPK activation enhances superoxide production and mitochondrial function while reducing disease activity.This study was supported by grants from the JDRF (KS and LLD) and the NIH for these studies (U01DK076133 KS, R01DK053867 KS, AG 030320 LLD).
PDGF receptor antagonism with imatinib mesylate improves renal hemodynamics independent of changes in blood pressure in Cyp1a1‐Ren2 transgenic rats with ANG II‐dependent malignant hypertension
Authors: Kwak Min-Young , Howard Catherine G , Mitchell Kenneth D 
Published: June 2021

The present study was performed to assess the effects of the PDGF receptor‐related kinase inhibitor, imatinib mesylate, on the renal hemodynamic changes that occur during the development of ANG II‐dependent malignant hypertension in Cyp1a1‐Ren2 transgenic rats. Male Cyp1a1‐Ren2 rats (n=5/group) were induced to develop malignant hypertension by dietary administration of indole‐3‐ carbinol (I3C, 0.3% wt/wt) for 10 days. One group was chronically treated with imatinib (60 mg/kg/d, oral gavage) starting 3 days before initiating I3C induction and maintained on imatinib for the duration of the study. In pentobarbital sodium anesthetized Cyp1a1‐Ren2 rats, mean arterial pressure was not significantly different between the induced group and the imatinib‐treated group (182±9 vs. 180±7 mmHg, NS). Rats treated with imatinib exhibited lower renal vascular resistance (31.5±3.0 vs. 45.2±7.0 mmHg/mL/min.g, P<0.05) and increased renal plasma flow (3.15±0.25 vs. 1.95±0.22 mL/min.g, P<0.01) and glomerular filtration rate (1.10±0.11 vs. 0.81±0.09 mL/min.g, P<0.05) compared with induced rats not treated with imatinib. The present data demonstrate that chronic blockade of PDGF receptor‐related kinase improves renal hemodynamics independent of changes in blood pressure in Cyp1a1‐Ren2 rats with ANG II‐dependent malignant hypertension.Support: NHLBI, Tulane COBRE in Hypertension and Renal Biology.
Protein O‐GlcNAcylation – A Novel Cell Survival Signal in Cardiac Stem Cells
Authors: Zafir Ayesha , Li Qianhong , Bolli Roberto , Jones Steven P. 
Published: June 2021

BackgroundClinical trials demonstrate the potential efficacy of stem/progenitor cell therapy in the post‐infarcted heart. Yet, the basic biology of these cells remains largely unexplored. Here, we demonstrate that protein O‐GlcNAcylation exerts a pro‐survival role in cardiac stem cells (CSCs).Methods/ResultsLin−/c‐kit+ CSCs sorted from the adult mouse heart responded to hypoxia‐reoxygenation by increasing protein OGlcNAcylation in a time‐dependent manner upon reoxygenation, along with significantly increased LDH release and caspase‐3/7 activity. We pharmacologically manipulated O‐GlcNAc levels in CSCs with loss‐ and gain‐of‐function approaches, i.e., inhibition of OGT (adds the O‐GlcNAc modification to proteins) by TT04 (0.001 mM), or inhibition of OGA (removes O‐GlcNAc) by ThG (0.025 mM) and subjected them to 3 h hypoxia, followed by 3 h reoxygenation. Reduction in protein O‐GlcNAcylation (via TT04) significantly exacerbated post‐hypoxic cell death (assessed by LDH release, MTS reduction, PI positivity), whereas augmenting O‐GlcNAc levels (via ThG) enhanced cell survival. Diminished OGlcNAc levels render CSCs more susceptible to the onset of post‐hypoxic apoptotic processes via elevated PARP cleavage by significantly enhanced caspase‐3/7 activation, whereas increasing O‐GlcNAcylation serves as a pre‐emptive pro‐survival signal in CSCs by significantly reducing caspase‐3/7 activity and cleaved PARP.ConclusionsProtein O‐GlcNAcylation represents a robust pro‐survival signal during hypoxia‐reoxygenation injury in CSCs and could be exploited to enhance cell survival prior to in vivo stem cell transplantation for myocardial infarction.Financial support: NIH, AHA.
*: p<0.05 vs. Normoxia Veh; #: p<0.05 vs. H/R Veh; n≥5/groupimage*: p<0.05 vs. Normoxia Veh; #: p<0.05 vs. H/R Veh; n≥5/group
Acoustic trauma reduces SLC4A11 expression in the mouse cochlea
Authors: Yamomoto Hiroshi , Wilson Teresa , Omelchenko Irina , Zhang Yuan , Nakashima Tsutomu , Shi Xiaorui , Nuttall Alfred L. 
Published: June 2021

RationaleThe solute carrier 4A11 (SLC4A11) protein, a plasma membrane bound sodium‐borate co‐transporter, is expressed in many different organs including salivary glands, kidney, cornea and the inner ear where it functions to maintain ion homeostasis. Its functional importance is underscored by the causative role of SLC4A11 gene mutations in several inherited diseases, all of which are characterized by some form of sensorineural defect.ObjectiveTo compare SLC4A11 gene expression with other members of the SLC4 family in the inner ear, eye and kidney and to examine the affect of acoustic trauma on its expression in the cochlea.Methods and ResultsBy quantitative real‐time PCR and immunoblot analysis, SLC4A11 transcript and protein levels in whole cochlea were markedly higher relative to eye and kidney, whereas SLC4A2 and SLC4A7 gene expression was quantitatively comparable among the three organs. Acoustic trauma resulted in a significant decrease in SLC4A11 transcript levels in the cochlear lateral wall. Further studies on cultured endothelial cells with chemical hypoxia mimetics revealed that down‐regulation of SLC4A11 can be mediated by hypoxia inducible factor.ConclusionHypoxia, a major source of damage to cochlear tissues from acoustic trauma, may be the mechanism responsible for the reduced levels of SLC4A11.Supported by grants 5R01DC000105 (ALN), 1R01DC010844 (XS), and P30DC005983.
NS6180, a new KCa3.1 blocker, inhibits T‐cell activation and dampens inflammation in a rat model of inflammatory bowel disease
Authors: Jenkins David Paul , Strobaek Dorte , Brown David T. , Chiu Peter , Jorgensen Susanne , Demnitz Joachim , Wulff Heike , Christophersen Palle 
Published: June 2021

The Ca2+‐activated K+ channel KCa3.1 is important in immune cell activation by providing part of the driving force for the Ca2+ entry leading to proliferation and cytokine production. Using a high‐throughput Ca2+‐activated Tl+‐influx assay in hKCa3.1 expressing HEK293 cells, we identified NS6180 (4‐[[3‐(trifluoromethyl)phenyl]methyl]‐2H‐1,4‐benzothiazin‐3(4H)‐one), a benzothiazinone defining a new class of KCa3.1 blockers. In patch‐clamp experiments NS6180 inhibited KCa3.1 with an IC50 of 11 nM via interaction with T250 and V275, the same pore amino acids mediating sensitivity to TRAM‐34. NS6180 blocked the endogenous KCa3.1 channel in human, mouse and rat erythrocytes with nearly identical potencies (15–20 nM). NS6180 suppressed rat and mouse splenocyte proliferation at submicrolar concentrations, but was without effect on splenocytes from KCa3.1−/− mice. NS6180 inhibited IL‐2, INF‐γ, IL‐4 and TNF‐α production but had no effect on IL‐17. NS6180 (3 and 10 mg/kg bid) inhibited DNBS‐induced colitis in rats as effectively as the benchmark therapeutic sulfasalazine (300 mg/kg). Animals treated with NS6180 showed significant improvements in colon weight, fecal occult blood, stool consistency, and body weight gain. We suggest benzothiazinone‐type KCa3.1 blockers as a novel class of anti‐inflammatory compounds and potential drugs.Funded by NeuroSearch
Down‐regulation of dysferlin and myoferlin in human airway epithelium: differential effects on cell morphology and adhesion
Authors: Leung Cleo , Shaheen Furquan , Hackett Tillie , Bernatchez Pascal 
Published: June 2021

Dysferlin and myoferlin belong to Ferlin protein family known to mediate endomembrane fusion events. Mutations of dysferlin lead to muscular dystrophy. Patients with dysferlinopathy show cardiopulmonary complications, suggesting that dysferlin may have functional roles in the pulmonary system. The high homology of myoferlin to dysferlin proposes that myoferlin may also play a role in lung pathology.ObjectivesTo examine dysferlin and myoferlin expression in human lungs and investigate the effects of silencing these genes in human airway epithelial cells (HAEC).MethodsDysferlin and myoferlin expression was evaluated by immunohistochemistry in human airway sections and by Western blot analysis in HAEC. Localization of dysfelrin and myoferlin in HAEC was studied using immunofluorescent staining. Effects of dysferlin and myoferlin knockdown on the morphology and adhesion of HAEC were also assessed.ResultsBoth dysferlin and myoferlin were present in the epithelium of human airway tissues and cultured HAEC. Dysferlin and myoferlin expression localized at the membrane and cytoplasm of HAEC. Knockdown of myoferlin, but not dysferlin, resulted in cell morphological changes, deficient cell adhesion and decreased the expression of zonular occludens 1 in HAEC.ConclusionPresence of dysferlin and myoferlin suggests they play potential roles in the adhesion of human airway epithelial cells.
Load‐Carrying Lumbar Spine Kinematics in Active‐Duty Marines
Authors: Rodriguez-Soto Ana Elvira , Jensen Andrew , Mayfield Jarrott , Jaworski Rebecca , Frank Lawrence , Ward Samuel Richard , Kelly Karen 
Published: June 2021

The purpose of this study was to measure kinematic changes in the lumbar spines of Marines carrying loads. We hypothesized that loads would increase lumbar lordosis and disc compression. Sagittal T2 MR images of the lumbar spine were acquired on a 0.6T vertical MRI scanner in 39 active‐duty Marines. Each Marine was scanned without load (BL) and after 45 min of standing with 50lbs of load (WL). Custom software was used to measure whole spine angles, intervertebral angles, and regional disc heights. Paired t‐tests were used to identify significant differences between tasks (α = 0.05). The overall position of the spine was significantly more horizontal at WL (71.6±6.8°) compared to BL (84.2±4.6°). Lumbar lordosis was reduced during WL (46.0±9.0°) compared with BL (58.2±9.1°). Sagittal intervertebral angles were significantly increased in L1L2 (BL=3.8±2.2°, WL=5.2±2.2°) and reduced in L4L5 (BL=10.2±2.7°, WL=6.9±4.5°) and L5S1 (BL=9.7±3.0°, WL=4.3±2.7°). Significant disc compression was evident anteriorly at L4L5 (BL=13.1±1.8mm, WL=12.5±2.4mm) and L5S1 (BL=12.4±2.9mm, WL=11.0±2.8mm) and reduced in the posterior region at L4L5 (BL=8.6±1.1mm, WL=9.1±1.4mm). Load carrying induced lumbar spine flexion, anterior disc compression and posterior disc distraction. These findings suggest a spine posture aimed to realign the center of mass of the soldier and load carrying system, but it may also increase lumbar spine susceptibility to shear‐load induced injuries.Grant Funding Source: US ARMY RDECOM N6311610MP00182