bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of endoplasmic reticulum chaperone protein BiP in endotoxin‐induced acute lung injury (669.10)
Authors: Fazal Fabeha , Schwarzenbart Amanda , Leonard Antony 
Published: June 2021

Endoplasmic reticulum (ER) makes up approximately 10% of the cell volume and plays an important role in multiple cellular processes such as calcium homeostasis, protein synthesis, folding and secretion, and lipid biosynthesis. Disturbances in ER homeostasis result in ER stress, which is implicated in a wide range of pathological conditions such as ischemic injury, neurodegenerative disorders, metabolic diseases and more recently in inflammatory conditions. A key step in the pathogenesis of acute lung injury (ALI), an inflammatory disease, involves alveolarcapillary membrane injury. This leads to infiltration of inflammatory cells into the alveolar airspaces and increased permeability, resulting in pulmonary edema. In this study, we report a critical role for ER chaperone and signaling regulator BiP in LPS‐induced ALI. Our data shows that AB5 cytotoxin family member subtilase cytotoxin (SubAB), which selectively cleaves and inactivates BiP, triggers ER stress and protects mice from endotoxin‐induced lung injury. In WT mice, LPS inhalation induced significant polymorphonuclear leukocyte (PMN) recruitment into bronchoalveolar lavage (BAL); however, mice pretreated to intraperitoneal injection of SubAB were protected from PMN influx into the alveolar airspaces. Consistently, LPS‐induced level of adhesion protein ICAM‐1, which plays a critical role in PMN adhesion and endothelial transmigration, was also reduced in SubAB treated mice. In addition, LPS‐induced microvascular permeability was restored upon SubAB pretreatment, as evidenced by a marked decrease in the level of albumin in the BAL. In contrast, SubAA272B, a SubAB active site mutant that cannot induce ER stress, failed to show the protective effect. These findings suggest that preconditioning the mice with ER stress ameliorates ALI caused by LPS.Grant Funding Source: NIH
Differentional effect of black raspberry extract on two primary human microvascular endothelial cells isolated from intestine and esophagus (669.2)
Authors: Medda Rituparna , Nie Linghui , Link Benjamin , Lyros Orestis , Otterson Mary , Rafiee Parvaneh 
Published: June 2021

BACKGROUND: Polyphenolic compounds (anthocyanins, flavonoid glycosides) in berries have been shown to prevent the carcinogenesis and tumorigenesis in esophagus and digestive tract. Angiogenesis has been implicated in the pathogenesis of inflammatory bowel disease (IBD). In this study, we aimed to determine the effects of black raspberry extract (BRE) on human primary microvascular endothelial cells isolated from intestine (HIMEC) and esophagus (HEMEC).METHODS: HIMEC and HEMEC monolayer were activated with either with VEGF or TNF‐α/IL‐1β with or without BRE. Effects of BRE on cells survival, apoptosis, proliferation, migration and tube formation were determined. COX‐2, ICAM‐1 and VCAM‐1 genes and proteins expression were assessed by qPCR and immunobloting and nuclear localization of p65 was observed by immunofluorescence staining.RESULTS: VEGF increased cell migration, proliferation and in vitro tube formation and BRE treatment of cells suppressed these effects in both HIMEC and HEMEC. TNF‐α/IL‐1β treatment translocated the p65 subunit of NFκB to nucleus, increased COX‐2, ICAM‐1 and VCAM‐1 gene and protein expression and the PGE2 activity in HIMEC and HEMEC. However, BRE treatment only was effective in inhibiting the COX2, NFκB and ICAM‐1 and VCAM‐1 in HEMEC, but exerted no inhibitory effect on HIMEC.CONCLUSIONS: Taken together, BRE is a potent anti‐inflammatory agent for HEMEC but not HIMEC.Grant Funding Source: MCW Digestive Disease
Soluble JAM‐C induces monocyte migration via Erk (669.5)
Authors: Tuma Elizabeth , Imhof Beat , Koch Alisa , Rabquer Bradley 
Published: June 2021

Purpose: The migration of leukocytes, including monocytes (MNs), is a major contributor to inflammation in autoimmune diseases such as rheumatoid arthritis (RA). In RA, MN migration to the joint synovial tissue is aided by junctional adhesion molecules (JAMs) expressed by endothelial cells (ECs). The EC JAMs bind integrins found on leukocytes, promoting their ingress. JAM‐C is the ligand for the integrin Mac‐1 (Cd11b/CD18). Like some adhesion molecules, JAM‐C has been found in soluble form, and our recent work has shown that soluble JAM‐C (sJAM‐C) is upregulated in RA synovial fluid. Some soluble adhesion molecules have also previously been shown to induce leukocyte migration. Based on this, we hypothesized that sJAM‐C promotes THP‐1 MN migration by binding Mac‐1 and inducing the phosphorylation of Erk.Methods &amp; Results: To test this hypothesis, we cultured THP‐1 cells to model MN function. Using qPCR (n=2) we found that THP‐1 MNs express the Cd11b portion of Mac‐1. Next, in vitro MN chemotaxis assays allowed us to determine that sJAM‐C is chemotactic for MNs in a concentration dependent fashion (n=3, p<0.05). In addition, our Western blotting showed that sJAM‐C induces the phosphorylation of Erk in a time dependent fashion (n=3).Conclusions: Our results indicate that THP‐1 MNs express Mac‐1, and suggests that sJAM‐C binding to Mac‐1 induces THP‐1 migration via the Erk pathway.Grant Funding Source: Supported by Albion College
Dedicator of cytokinesis 2, a novel regulator for vascular smooth muscle cell phenotype modulation and vascular remodeling (670.3)
Authors: Guo Xia , Cui Xiao‐Bing , Wang Jia‐Ning , Shi Ning , Fukui Yoshinori , Chen Shi‐You 
Published: June 2021

The objective of this study is to determine the role of dedicator of cytokinesis 2 (DOCK2) in vascular smooth muscle cell (VSMC) phenotypic modulation and vascular remodeling. Platelet‐derived growth factor‐BB (PDGF‐BB) induced DOCK2 expression while modulating VSMC phenotype as indicated by reduced VSMC marker expression. DOCK2 overexpression inhibited while DOCK2 knockout enhanced SMC marker gene expression in primary VSMC. Mechanistically, DOCK2 regulated VSMC phenotype through suppression myocardin/serum response factor (SRF)‐mediated transcription of VSMC marker genes. DOCK2 blocked myocardin, but not SRF expression and inhibited myocardin‐activated α‐SMA promoter activity. DOCK2 was also essential for PDGF‐BB‐induced VSMC proliferation and migration. DOCK2 stimulated VSMC migration via induction of focal adhesion contact and stress fiber formation. By using both rat carotid artery balloon‐injury and mouse ligation injury models, we observed that DOCK2 was highly induced in injury‐induced neointima. Knockdown of DOCK2 dramatically inhibited the neointima formation by 60%. Most importantly, knockout of DOCK2 in mice markedly blocked ligation‐induced intimal hyperplasia. These data demonstrate that DOCK2 plays an important role in VSMC phenotypic modulation and vascular lesion formation following vascular injury.Grant Funding Source: HL093429 and HL107526 to Shi‐You Chen, Pre‐doctoral Fellowship Award 12PRE12030180 to Xia Guo
Neutrophil depletion: beneficial or detrimental to post‐ischemic hind limb recovery in Cx40‐/‐ vs. WT mice? (670.8)
Authors: Good Miranda , Barendrick Lindsay , Oulton Jeremy , Burt Janis 
Published: June 2021

Connexins (Cx) regulate vascular function, remodeling, and the inflammatory response in various vascular diseases. Recovery of post‐ischemic hindlimb use and perfusion is significantly impaired in mice with global deletion of Cx40 (Cx40‐/‐), and infiltrated activated macrophages were significantly more numerous in the ischemic limbs of these mice 14 days post‐injury as compared to wild type (WT) mice. Here we begin to explore whether the inflammatory response in the Cx40‐/‐ mice is detrimental to its post‐ischemic recovery process. At both 8 hours and 24 hours post‐femoral artery ligation (FAL), Cx40‐/‐ mice had a significantly larger number of infiltrated neutrophils in the ischemic gastrocnemius muscle compared to WT mice. This increased infiltration did not, however, lead to any differences in number of infiltrated activated macrophages at 3 days post‐ischemic injury in Cx40‐/‐ and WT mice. Additionally, no differences in Cx37 or Cx40 expression were detected as a consequence of ischemia in WT and Cx40‐/‐ mice, despite genotype‐specific differences in Cx37 localization. To assess the impact of excessive neutrophil infiltration on post‐ischemic recovery of limb use and perfusion, we neutrophil depleted mice by injecting 500µg of anti‐m Ly‐6G antibody (clone: RB6‐8C5) 1 day prior to, day of, and 1 day post‐surgery. Preliminary data indicate that neutrophil depletion did not significantly improve or impair recovery of limb use in WT or Cx40‐/‐ mice; however, a trend indicative of impaired limb perfusion was observed in neutrophil depleted WT, but not Cx40‐/‐ mice. These results suggest that neutrophil infiltration may support post‐ischemic recovery in WT mice, but does not improve or diminish recovery of Cx40‐/‐ mice.Grant Funding Source: Supported by HL058732
Ischemic stroke‐induced increases in circulating microparticles promote leukocyte adhesion in intact microvessels (672.3)
Authors: Petrides Pete , Tan Zhenjun , Xu Sulei , Guo Ge , Huber Jason , Rosen Charles , He Pingnian 
Published: June 2021

Studies in both stroke patients and experimental animals indicate an association between ischemic stroke and post stroke peripheral inflammation, but the mechanisms are poorly understood. Our ongoing study indicated that circulating microparticles (MPs), the small vesicles released from the cell membrane upon activation, were significantly elevated in both patients and animals with diabetes, and increased circulating MPs with phosphatidylserine (PS) exposure on their outer membrane played important roles in the development of diabetes‐associated microvascular complications. The objective of this study was to investigate whether local ischemic stroke produced increased circulating MPs and determine their impact on post stroke‐associated peripheral vascular inflammation. Acute cerebral ischemia was induced by occlusion of the right middle cerebral artery (MCAO) in 3‐4 month old rats using an autologous blood clot. Functional assessment, lesion volume, and hemispheric swelling were evaluated at 24h after MCAO. Plasma MPs 24h after stroke induction were quantified and characterized using flow cytometry. The number of PS exposed MPs in stroke plasma, identified by Annexin V binding, significantly increased from 5.0 x 103 (normal rats) to 30 x 103 per µl. Antibodies directly against cell specific antigens were used to differentiate the MP cell origin. Results showed that 67% of the increased stroke plasma MPs were derived from platelets. Perfusion of individually cannulated normal rat mesenteric microvessels with isolated stroke MPs for 30 min followed by 10 min of resumed blood flow induced a 4‐fold increase in leukocyte adhesion compared to baseline. These results indicate that stroke‐induced increased circulating MPs serve as mediators capable of disseminating local inflammation to remote vasculatures, and therefore, promoting post stroke systemic complications.Grant Funding Source: Supported by HL56237, DK097391, NS061954
Effects of brief ischemia on oxygen consumption, tissue oxygenation, and blood flow during recovery from ischemia in rat skeletal muscle (674.13)
Authors: Dodhy Sami , Golub Aleksander , Pittman Roland 
Published: June 2021

The effects of brief ischemia (5, 15, 30, and 60 s duration; Isch) on interstitial PO2 (PISFO2), arteriolar PO2 (PaO2), blood flow (Q) and O2 consumption (VO2) during the recovery period was observed in exteriorized spinotrapezius muscles of 29 male Sprague‐Dawley rats (284 ± 20 g) for intravital microscopy. Phosphorescence quenching microscopy was used to obtain PISFO2, PaO2 and VO2. Arteriolar blood flow was calculated from arteriolar diameter and centerline RBC velocity obtained from an Optical Doppler Velocimeter. Ischemia was initiated by rapidly pressurizing an airbag attached to the microscope objective for a selected ischemic duration. The average baseline value of arteriolar blood flow was 5.8±0.8 µl/min; as expected, reactive hyperemia was observed during the recovery from Isch. Flow recovery (dQ/dt) was fastest [3.88±0.64 (µl·min‐1)/s] after 60 seconds of Isch. Average baseline PISFO2 was 62±4 mmHg; PISFO2 decreased to 75%, 34%, 10% and 2% of baseline following 5, 15, 30 and 60 s of Isch, respectively. Up to 30 s of ischemia, the rate of recovery of PISFO2 steadily increased as the ischemic duration increased; however, it dropped off following 60 s of ischemia. The drop in the rate of recovery of PISFO2 despite an increase in flow recovery following 60 s of ischemia is suggestive of a period of imbalance during which the rate at which the tissue was consuming oxygen temporarily exceed the rate at which it could be supplied. The rate of recovery of PISFO2 was fastest (4.2±0.7 mmHg/s) following 30 s of Isch. Average baseline VO2 was 120±19 nl O2/cm3·s and it increased above baseline during the early part of the recovery period. The time course of recovery of PISFO2 represented a balance between O2 delivery, proportional to local arteriolar blood flow, and local VO2.Grant Funding Source: NHLBI grant HL18292
Effects of oxygen affinity and viscosity of a hemoglobin‐based oxygen carrier (HBOC‐201) on systemic and microcirculatory variables in a top‐load rat model (674.2)
Authors: Song Bjorn , Nugent William , Moon‐Massat Paula , Pittman Roland 
Published: June 2021

The effects of oxygen affinity (P50) and viscosity on arteriolar vasoactivity and tissue oxygen tension were explored by administering a polymerized bovine hemoglobin‐based oxygen carrier (HBOC) in a dose‐response fashion to normovolemic rats. The P50 and viscosity, respectively, of the parent compound (HBOC‐201) and its modifications (MP50 and LP50A) were as follows: 40 mmHg and 3.0 cP (HBOC‐20l); 18 mmHg and 4.4 cP (MP50); and 17 mmHg and 12.1 cP (LP50A). Anesthetized male Sprague‐Dawley rats (N = 32) were randomized to receive one of the HBOC solutions, and were administered with four infusions that increased in concentration for each dose (2, 22, 230 and 780 mg/kg, IV). Data were compared to rats receiving an equivalent volume for each of the four infusions (0.4, 0.4, 3.8, 13.1 ml/kg, IV) of iso‐oncotic 5.9% human serum albumin (HSA). HBOC‐201, MP50 and HSA produced significant increases in MAP after Doses 3 and 4, whereas a similar increase began at a lower dose (Dose 2) with LP50A. There were no significant changes in arteriolar diameters at any dose for any group. Interstitial PO2 remained unchanged for HBOC‐201, MP50 and HSA, but LP50A caused a significant decrease compared to baseline after Doses 3 and 4. In this healthy rat top‐load model, there was no evidence that HBOC‐201 would perform better with increased oxygen affinity (40 to 18 mmHg) or viscosity (3.0 to 4.4 cP).Grant Funding Source: Supported by BUMED congressional funding WUN 604771N.9737.001.A0315, and in part by R01 HL18292
A new model for metabolically‐linked regulation of local blood flow (674.5)
Authors: Golub Aleksander , Pittman Roland 
Published: June 2021

In skeletal muscle an increase in O2 consumption over a wide range evokes a proportional increase in LBF. The regulation of LBF ensures matching the delivery of materials with their rate of consumption. The mechanism by which this happens is thought to operate according to the metabolic hypothesis of LBF control, whereby an increase in tissue hypoxia (caused by an imbalance between O2 demand and supply) stimulates the production of metabolites by the hypoxic cells which further open blood vessels and lead to increased blood flow and O2 supply. The drawback of this model is the inevitable maintenance of tissue hypoxia. An alternative mechanism to explain the matching of LBF to demand in O2 and nutrients is proposed which depends on the interaction of two naturally occurring signaling radicals, nitric oxide (NO), constantly produced by endothelial cells, and superoxide (O2‐), produced primarily by the parenchymal cells. These two highly reactive molecules interact in the interstitium at a rate controlled by diffusion to determine the level of the vasodilator NO. The proposed mechanism is based on the concept that functional activity is the normal physiological state for a tissue; the corresponding normal state for its vasculature is dilation. The goal of regulation is maintaining a sufficient, but not excessive, supply of O2 and substrates to the cells. This mechanism explains why the vasodilation signal is generated by microvessels, and how the parenchymal cells block this signal when LBF provides a sufficient supply of O2 and substrates. Production of O2‐ by membrane NAD(P)H oxidase depends on the balance of glycolysis and oxidative phosphorylation via the availability of NADH and NAD(P)H in the cytosol and the interstitial PO2. Thus, the coupling of tissue metabolic activity with LBF is achieved.Grant Funding Source: Supported by NHLBI HL18292
Impaired skeletal muscle fatigue resistance in metabolic syndrome is associated with alterations in microvascular hematocrit levels and variability (675.3)
Authors: Butcher Joshua , Stanley Shyla , Brooks Steven , Chantler Paul , Wu Fan , Frisbee Jefferson 
Published: June 2021

Vascular dysfunction in metabolic syndrome is associated with poor performance of in situ skeletal muscle. Prior to impaired function in skeletal muscle itself, this reflects a failure to effectively perfuse working muscle. While altered vascular reactivity, arteriolar wall stiffness and microvessel rarefaction have been implicated, the accumulated impact on mass transport/exchange is unknown. Using tracer washout and existing models for microvascular hematocrit (HMV) and permeability‐surface area product (PS), we determined these parameters for in situ skeletal muscle of lean (LZR) and obese Zucker (OZR) rats. HMV in OZR was less than for LZR; treatment with adrenergic blockers or anti‐oxidants improved HMV slightly, but imposition of all agents restored HMV fully. PS, reduced in OZR vs. LZR, was not impacted by intervention. Using in situ cremaster muscle, HMV was determined in individual microvessels. Similar to above, HMV was reduced in OZR vs. LZR, although variability was higher; with post‐intervention changes mirroring that from washout experiments. These data suggest a low, spatially variable, HMV and global loss in surface area are contributors to poor muscle performance in OZR.Grant Funding Source: Supported by National Institutes of Health and American Heart Association
Thrombospondin‐1 null mice exhibit enhanced microvessel endothelium dependent vasodilation, reduced adrenergic sensitivity (676.10)
Authors: Mandler W. Kyle , Nurkiewicz Timothy , Olfert I. Mark 
Published: June 2021

Thrombospondin‐1 null mice exhibit enhanced microvessel endothelium dependent vasodilation, reduced adrenergic sensitivity The extracellular matrix protein thrombospondin ‐1 (TSP‐1), is an antagonist of nitric oxide‐mediated vascular relaxation by preventing activation of guanylate cyclase and other downstream targets. Our objective is to determine the effects loss of TSP‐1 loss on microvascular reactivity.Arteriolar responses to acetylcholine, phenylephrine, and adenosine, were assessed in skeletal muscle microvasculature of global TSP‐1 null (KO) and wildtype (WT) littermate mice using intravital microscopy with the gluteus maximus.KO animals demonstrated 10.7%, 18.6%, 16.5% greater vasodilatory response to acetylcholine concentrations of 10‐6, 10‐4, and 10‐2M (p < 0.05). WT vessels demonstrated more constriction than KO at the highest concentration of phenylephrine, 10‐3M (p < 0.05). KO vessels demonstrated greater vasodilatory capacity (p < 0.05), to 10‐2M adenosine. WT animals had a 23.8% greater (p < 0.05) vasoconstriction in response to the highest dose of phenylephrine, 10‐3M. KO animals demonstrated a 23.5% higher (p < 0.05) maximal dilatory capacity in response to 10‐2M adenosine than WT. These data provide evidence that TSP‐1 is an important physiologic regulator of skeletal muscle microvascular reactivity.
A novel ex vivo tissue culture assay for determining the effects of anti‐tumor drugs on angiogenesis (676.14)
Authors: Azimi Mohammad , Mathur Aditi , Mondal Debasis , Murfee Walter 
Published: June 2021

Tumor growth is highly dependent upon angiogenesis and the interplay between the tumor stroma and the microvasculature. A challenge in evaluating anti‐tumor therapies is the inability to decouple treatment effects on cancer cells versus the microvascular network. Recently, our laboratory demonstrated that the “rat mesentery culture” model could be used for time‐lapse comparison of intact microvascular networks before and after angiogenesis induction. The objective of this study was to demonstrate that this model could be used to evaluate the anti‐angiogenic effects for a given drug treatment. Mesenteric windows were harvested from adult male Wistar rats and cultured for 3 days in serum containing medium (MEM + 10% Fetal Bovine Serum). Explants were exposed to increasing concentrations of Nelfinavir (Viracept™) (0 ‐ 4.5 μM) and Curcumin (0 ‐ 4.5 μM). Nelfinavir and Curcumin were selected for the study because Nelfinavir causes endothelial dysfunction and Curcumin, an anti‐oxidant and NF‐κB inhibitory dietary supplement, is known to have anti‐angiogenic effects. Preliminary studies also suggest that the combination of Nelfinavir/Curcumin produce synergistic anti‐cancer effects. Labeling tissues with FITC conjugated BSI‐lectin on Day 0 and Day 3 identified endothelial cells along all vessels. Results showed significant dose‐responsive effects of Nelfinavir/Curcumin combinations in suppressing both vessel segment density and the number of capillary sprouts per vascular area. Our findings establish the rat mesentery culture model as a valuable ex vivo tool for the rapid and reproducible screening of drug effects on angiogenesis in an intact network scenario.Grant Funding Source: Supported by Tulane Center for Aging and NIH 5‐P20GM103629‐02
Maximal local thermal hyperemia in able‐bodied and spinal cord injured humans (677.10)
Authors: Zhao Joan , Trbovich Michelle , Wu Yubo , McMahan C. , Kellogg Dean 
Published: June 2021

Paraplegic spinal cord injury alters local thermal hyperemic responses. We hypothesized that a similar effect would be observed in tetraplegia. 6 able‐bodied (AB), 5 paraplegic (PARA), and 5 tetraplegic (TETRA) age and gender matched subjects participated. Skin blood flow (SkBF) was monitored by laser‐Doppler flowmetry (LDF) from forearm and calf sites. Local skin temperature (Tloc) was controlled with combined LDF/local heating probe holders. Tloc was measured with thermocouples placed between the probe holders and the skin. Mean arterial pressure (MAP) was recorded by Finapres. After instrumentation, Tloc was increased slowly from normothermic levels to 42°C and maintained at that temperature for at least 25 minutes to cause maximal local vasodilation. Cutaneous vascular conductance was calculated as CVC=LDF/MAP and analyzed by ANOVA. Results: At Tloc=42°C, CVC measured from forearm skin was 47±7mV in AB, 49±8mV in PARA, and 42±8mV in TETRA. These responses did not statistically differ among groups. At Tloc=42°C, CVC measured from calf skin was 26±7mV in AB, 50±8mV in PARA, and 42±8mV in TETRA. These responses differed between AB and PARA (p=0.04) and tended to differ between AB and TETRA (p=0.15). Within groups, forearm responses tended to be greater than calf responses in AB (p=0.06), but not in PARA and TETRA groups. We conclude that spinal cord injury alters maximal SkBF levels in the calf, but not the forearm. In AB persons, maximal SkBF tends to be lower in the calf than the forearm (supported by NIH Grant R03NS083961).Grant Funding Source: Supported by NIH R03NS083961