bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Marine Compounds Modulate Mitochondrial Function in H9c2 Cells: Potential New Pharmaceutical Targets to Control Cardiac Metabolism
Authors: Warmbrunn Moritz Valerian , Schilling Jan M. , Dhanani Mehul , Glukhov Evgenia , Gerwick Lena G. , Gerwick William H. , Patel Hemal H. 
Published: June 2021

IntroductionThe global burden of cardiovascular disease is increasing and is the leading cause of morbidity and mortality worldwide. As the heart is a highly metabolic organ, mitochondrial health is critical to normal cardiac function and is compromised in a number of cardiac diseases. Therefore, new pharmaceutical agents and screening tools to modulate and evaluate cardiac metabolism may offer novel therapeutics for cardiovascular disease.MethodsA number of marine compounds have been curated over the years by faculty at the Scripps Institution of Oceanography. Chemical structures have been largely elucidated through nuclear magnetic resonance spectroscopy and mass spectrometry, and these have been broadly available for biological screening through the UCSD Center for Compound Resources. Seventy‐three promising marine compounds were evaluated by application on H9c2 rat cardiomyoblasts while measuring oxygen consumption rate and extracellular acidification rate with a Seahorse XF96 extracellular flux analyzer. Mitochondrial metabolism was tested at a range of compound concentrations (0.1–1.6 mM). Subsequently, dose response curves of compounds that showed biological activity in the initial screen were performed. Dose response assay concentrations ranged from 0.01 nM to 3 μM with vehicle only as the control.ResultsEight compounds showed significant dose dependent alterations in mitochondrial metabolism in the initial screen. Dose response assays of glycospongosine revealed an increase in ATP linked‐maximal respiration ratio. In contrast, higher glycospongosine concentrations led to a gradual dose dependent decrease in reserve capacity. Injection of leptochelin A first increased basal respiration of the cardiomyoblasts, after the first increase, basal respiration gradually decreased. Increasing concentrations of honaucin A lowered the maximal mitochondrial respiration dose dependently. In addition, kabiramide C decreased maximal respiration normalized to basal respiration.ConclusionWe present here the results of screening multiple marine natural products in a cell based metabolic assay. Marine compounds have a demonstrated potential to modulate cardiac metabolism in a variety of settings; however, further research in disease models is necessary to determine if such modulation via these compounds is beneficial or harmful to cardiovascular disease.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Single‐cell Measurement of Red Blood Cell Oxygen Delivery Rate
Authors: Chng Ziyang Kevin , Ng Yan Cheng , Kim Sangho 
Published: June 2021

Oxygen (O2) is supplied throughout the body by hemoglobin (Hb) bounded in red blood cells (RBCs). The ability of red blood cells to deliver oxygen has been routinely assessed by P50 using clinical hematology analyzers, defined as the partial pressure of oxygen (PO2) required to saturate the hemoglobin (Hb) in RBCs to 50%. Although this defines the ability of RBCs to carry O2 under equilibrium states, it cannot determine the efficacy of O2 delivery in the dynamic blood flow, which could occur over the span of ~3 s in the microcirculation. Furthermore, while various factors such as pH, temperature and 2,3‐diphosphoglycerate (2,3‐DPG) affecting the O2 dissociation curve (ODC), it is unclear how, and the variations of these factors, may influence the RBC O2 delivery on the cellular level. Therefore, in this study, we developed a microwell array oxygen‐sensing chip for measuring the rate of O2 delivery from RBCs at a single‐cell level. Washed RBCs were re‐suspended in an oxygen‐sensitive fluorescence dye solution (ruthenium tris(2,2′‐dipyridyl) dichloride hexahydrate, RTDP, 1 mg/mL) and introduced into the microfluidic device. After trapping of single RBCs in the microwells, heavy mineral oil is used to flush excess RBCs and to isolate single RBCs in the microwell array. Subsequently, the fluorescence intensity of the oxygen‐sensitive dye in the microwell was measured as it gets deoxygenated by N2 gas separated by a PDMS membrane. RTDP fluorescence is quenched in the presence of O2, the fluorescence intensities in the microwells increase as they get deoxygenated by the continuous flow of N2 gas. The rate of O2 release from the single RBC trapped in the microwells, however, would alter the rate of change of microwell PO2 (Fig. 1b). Accordingly, RBCs with higher rates of O2 release would reduce the overall rate of deoxygenation in the microwell, thus reducing the rate of decrease in the PO2. To demonstrate the sensitivity of the device, we deoxygenated the microwells containing RBCs and RBC ghosts (n = 20). As expected, the PO2 in the microwells containing RBCs was significantly higher (p < 0.0001) than that containing RBC ghosts (without Hb), due to O2 release from Hb bounded in the RBCs. Additionally, we investigated the potential difference in the O2 delivery rate between density‐fractionated young (top 5% fraction) and old RBCs (bottom 5% fraction). The obtained results showed an apparent difference in the PO2 in microwells with young and old RBCs is statistically significant (p < 0.0001), suggesting that senescent RBCs have a lower O2 delivery rate.Support or Funding InformationNational Medical Research Council (NMRC)/Cooperative basic Research Grant (CBRG)/‐‐78/2014This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
ADAM17 via F11R/JAM‐A Shedding Regulates Flow/Wall Shear Stress Mechanosensing in Endothelial Cells
Authors: Christianson Stephenie , Dou Huijuan , Li Xueyi , Fulton David , Rudic Daniel , Bagi Zsolt 
Published: June 2021

Reduced or increased blood flow induces arterial remodeling and is critically mediated by proper endothelial cell (EC) mechanosensing of flow/wall shear stress (WSS). A disintegrin and metalloproteinase ADAM17 sheds F11R/JAM‐A, an important tight junction‐located endothelial cell adhesion molecule. Consequently, both ADAM17 and F11/JAM‐A have been previously implicated in arterial remodeling. Therefore, we tested the hypothesis that ADAM17 regulates EC mechanosensing via F11R/JAM‐A shedding. We found that compared to static/zero flow (WSS=0 dyne/cm2), cultured ECs exposed to increasing levels of flow (4 to 8 dyne/cm2) progressively changed their orientation in the direction of the flow. Ultimately, the ECs reaching maximum alignment at the physiologic, 8 dyne/cm2 WSS levels during the first 72 hours of culture. After siRNA‐mediated silencing of F11R/JAM‐A, ECs failed to efficiently orient with the direction of flow, whereas overexpression of F11R/JAM‐A facilitated enhanced EC alignment. In the presence of recombinant ADAM17 or through stimulation of ADAM17 by phorbol myristate acetate, ECs failed to orient to flow. Whereas gene transfer of the ADAM17 cleavage resistant, mutated JAM‐A(V227Y) resulted in a normal flow orientation. Our results uncover a novel regulatory role for ADAM17 in modulating F11R/JAM‐A‐dependent flow/WSS mechanosensing in ECs.Support or Funding InformationNIH‐NIA R01AG054651This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Preadipocyte differentiation in GelMA hydrogels for mechanical testing
Authors: Sakai Andrei , Menon Naveen R. , Rutkowski Joseph 
Published: June 2021

The aberrant expansion of adipose tissue in obesity is characterized by chronic inflammation and fibrosis. The extracellular matrix that surrounds all cells plays an important biological and mechanical role in regulating cell differentiation, expansion, and homeostasis. Adipocyte dysfunction, indicated by cellular insulin resistance, dysregulated lipolysis, and inflammatory cytokine secretion, may therefore be driven in part by the newly fibrotic obese matrix in adipose tissue. Tissue engineering approaches have largely looked at the biological compatibility of tissue mimetics while assuming the mechanics are sufficient; this is in large part because tuning stiffness often results in significant porosity changes. Jaiswal et al. described the fabrication of GelMA gels with stiffness control by using a crosslinking nanoparticle as a matrix reinforcing agent (Jaiswal et al., ACS Nano, 2016). We sought to utilize these gels to determine the optimum modulus for adipocyte differentiation and metabolic responsiveness. Model 3T3‐L1 and primary scWAT (subcutaneous white adipose tissue), and BAT (brown adipose tissue) preadipocytes were cast into GelMA gels produced with different crosslinking nanoparticle sizes (8 nm, 12 nm) and varying in concentration (0.5 mg/mL or 2.5 mg/mL). GelMA gels without nanoparticles were used as a control system. The cells were exposed to differentiation media from day 0–8/9 and were analyzed regarding protein/gene expression, morphology, and metabolite handling. Preliminary results for the 3T3L1 indicate lower adipocyte differentiation for the 12‐nm GelMA gels inferred by the low expression of FABP4. Also, CIDEA and PGC1a expression were found reduced for the 8‐nm 2.5 mg/mL and the 12‐nm gels, which means a less pro‐apoptotic behavior and lower levels of mitochondrial biogenesis for the cells in stiffer matrices. Surprisingly, types 1a1/3a1/4a1 collagen expression clearly reduced with the increasing stiffness (higher expression for the GelMA control and lower expression for the 12‐nm GelMA) which can be related to generating a less fibrotic extracellular matrix. Similarly, TNFa and IL‐10 expression were inversely correlated with GelMA stiffness. Confocal microscopy imaging using BODIPY staining for the lipid droplets and anti‐GLUT4/HRP‐Alexa 456 indicate a better differentiation for the primary cell lines (scWAT and BAT). Cells thus appear to prefer stiffer GelMa gels compared to Type I collagen. n summary, GelMA gels showed to be a promising model for adipocyte differentiation. A deeper understanding of the microenvironment of fibrotic adipose tissue may provide new perspectives to obesity therapeutics and provide a physiologically‐relevant mechanical environment in which to study adipocyte interactions with lymphatic endothelial cells.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Presence of IL6 and IL8 receptors within mesenteric and skeletal muscle microvessels in mice
Authors: Vigilance Jacqueline E. , Yin Wei D. , Gha Joohee , Tam Gregory , Frame Mary D. 
Published: June 2021

Metabolic diseases like inflammatory conditions result in an upregulation of proinflammatory cytokines (Diabetes Research and Clinical Practice: 105(2); 141–50, 2014). We have previously examined vasoactive response to IL6 and IL8 in mesenteric and skeletal muscle microvessels in normal wild‐type C57 BL/6J and leptin‐deficient db/db mice. Due to the apparent cross‐talk with endothelin related vasoactive responses (The FASEB Journal 27: 687.15, 2013), we confirmed the presence of these receptors within the tissues. Receptors were identified using immunofluorescence with specific antibodies directed towards the IL6 (ABCAM ab83053) and IL8 (CXCR2, ab14935) receptors. Mesenteric tissues and skeletal muscle tissues from C57BL/6J mice [obtained through a tissue sharing facility at SBU] were fixed in 4% paraformaldehyde overnight, then in 30% sucrose in saline overnight to 5 days, imbedded in freezing medium (optimal cutting temperature compound, OCT) and kept at −80C until use. Tissues were sliced 10 um thick using a cryotome. Tissues were first incubated at room temperature with blocking buffer (0.2% BSA). Primary antibodies were diluted to 1:50 to 1:200, and tissues incubated for 30–60 minutes, rinsed 3–6 times with PBS, and then incubated with FITC IgG secondary antibodies (1:50–1:200) for 30–60 minutes, with a final wash in PBS (3–6 times). Tissues were mounted with fluormount and kept cool in the dark until imaging. The results showed that in both mesenteric microvessels and skeletal muscle microvessels, there was a punctate appearance along the axial distribution of vessels indicative of positive staining to both IL6 and IL8 receptor antibodies. These results indicate that vasoactive responses to the IL6 and IL8 cytokines may be specific in nature, and not solely through the endothelin receptor system. We have not ruled out a potential interaction between separate receptor systems as being a requirement for vasoactive responses.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Pyridoxamine attenuates age‐related impairments in cerebral artery endothelial function
Authors: Walker Ashley E. , Meza Antonio E. , Earl Alex E. , Machin Daniel R. 
Published: June 2021

Age‐related impairments to cerebral artery endothelial function are thought to be a key contributor to the increased risk for cerebrovascular diseases that occur with advancing age. However, there are a limited number of clinical interventions to prevent age‐related cerebral artery endothelial dysfunction. A novel potential intervention is to prevent advanced glycation end‐product (AGE) formation with pyridoxamine. AGEs can increase oxidative stress and reduce nitric oxide (NO) bioavailability, potentially leading to endothelial dysfunction. Pyridoxamine, a natural form of vitamin B6, prevents the conversion of stable sugar‐protein adducts (Amadori compounds) to AGEs. Thus, we sought to determine if long‐term pyridoxamine treatment initiated in middle‐age can prevent age‐related cerebral artery endothelial dysfunction and preserve NO bioavailability.We administered pyridoxamine (2 g/L in drinking water) or vehicle control for 6 months to C57BL/6 mice. We assessed cerebral artery endothelial function by endothelium‐dependent dilation (EDD, maximal response to acetylcholine) in the middle cerebral artery (MCA) of old pyridoxamine‐treated (n=11, 24.8±0.2 mo), old vehicle control‐treated (n=10, 24.8±0.2 mo), and young untreated (n=7, 7.4±0.0 mo) mice. MCA EDD was lower in old vehicle control compared to young untreated mice (30.5±3.9% vs. 50.0±4.8%, p=0.003). However, MCA EDD of old pyridoxamine‐treated mice was partially preserved compared with old vehicle control mice (42.5±4.5%, p=0.03), but was not different from the young untreated mice (p=0.29). After incubation with NO synthase inhibitor L‐NAME, the dilatory response was not differ between groups (p>0.05), indicating that increased NO bioavailability mediated the preservation of MCA EDD by pyridoxamine in old mice. Endothelium‐independent dilation was not different between groups (p>0.05).In conclusion, long‐term pyridoxamine treatment preserves, at least in part, cerebral artery endothelial function and NO bioavailability with advancing age.Support or Funding InformationNIH AG046326 and a University of Utah Center on Aging Pilot AwardThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Arterial smooth muscle cell PKD2 (TRPP1) channels control systemic blood pressure
Authors: Fernandez‐Pena Carlos , Bulley Simon , Hasan Raquibul , Leo M. Dennis , Muralidharan Padmapriya , Mackay Charles , Evanson Kirk W. , Burris Sarah K. , Wang Qian , Kuruvilla Korah P. , Jaggar Jonathan H. 
Published: June 2021

Hypertension, a disease that afflicts more than one quarter of the World's population, is a major risk factor for cardiovascular diseases. Blood pressure is determined in part by arterial smooth muscle cells (myocytes) that alter resistance vessel tone. In vivo mechanisms that regulate myocyte contractility to control physiological blood pressure and become pathological during hypertension are poorly understood. Several Transient Receptor Potential (TRP) channels are proposed to be expressed in arterial myocytes, although it is unclear if these proteins control physiological blood pressure and can be targeted to alleviate hypertension. Here, we generated the first inducible, smooth muscle‐specific knockout for a TRP channel, namely for PKD2 (TRPP1), to investigate blood pressure regulation by this protein. Data indicate that PKD2 knockout dilates resistance‐size systemic arteries and reduces blood pressure. We show that heterogeneous stimuli activate PKD2 channels in arteries of different organs. Intravascular pressure stimulate PKD2 channels in skeletal muscle arterial myocytes, whereas α1‐adrenergic receptors activate PKD2 channels in myocytes of mesenteric arteries. Regardless of the stimulus or arterial bed, PKD2 current activation in myocytes leads to vasoconstriction. Hypertension is associated with an increase in the abundance of plasma membrane PKD2 channels in systemic arteries. Myocyte‐specific PKD2 knockout caused vasodilation, lowered systemic blood pressure and prevented arterial remodeling during hypertension. In summary, we show that PKD2 channels are activated by distinct vasoconstrictor stimuli in arterial myocytes of different tissues, control physiological systemic blood pressure, are upregulated during hypertension and knockout reduces high blood pressure. These data suggest that targeting of arterial myocyte PKD2 channels could be exploited to control blood pressure and alleviate cardiovascular diseases.Support or Funding InformationThis study was supported by NIH/NHLBI grants HL67061, 133256 and HL137745 to J.H.J, and American Heart Association Scientist Development Grants to S.B and M.D.L.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Preventing Hypertension After Ischemic Stroke In The Spontaneously Hypertensive Rat
Authors: Thakkar Pratik C. , Barrett Carolyn Judith , Guild Sarah‐Jane , McGregor Ailsa , Paton Julian Francis Richmond , McBryde Fiona Dianne 
Published: June 2021

Over 80% of patients show a transient increase in blood pressure (BP) after ischemic stroke, regardless of their previous blood pressure level. However, whether this increased pressure is necessary to enhance or maintain oxygenation of penumbra tissues remains uncertain. We aimed to determine the impact of treating post‐stroke hypertension in the spontaneously hypertensive (SH) rat model of ischemic stroke.Male SH rats (374±9 g) were instrumented to allow the long‐term recording of BP, intracranial pressure (ICP) and brain tissue oxygen in the penumbra (pO2) via telemetry. After recording a 3‐day baseline on Day 0 an ischemic stroke was induced via a two‐hour occlusion of the middle cerebral artery (MCAo). BP was either Untreated (n= 6) or Treated (n=6) and controlled to baseline levels with the clinically‐indicated adrenergic antagonist, labetalol (0.25 mg/kg/hr sc via osmotic pump). Behavioural testing and neurological scoring (SHIRPA score) were performed on Days 1, 3, 7 and 10 to evaluate the functional recovery from stroke over time, and postmortem stroke infarct size assessed by histology on Day 10.Following a stroke, BP increased rapidly in Untreated SH rats, reaching a peak of 35±3 mmHg above baseline within 24 hours. Treatment with labetalol significantly reduced BP on D0 and D1 (p<0.05), which in combination with a small increase in ICP (3±0.8 mmHg in Untreated; 0.4±0.3 mmHg in Treated; p=0.047) on D0 resulted in a lower cerebral perfusion pressure (CPP=MAP‐ICP) in Treated animals. Penumbra tissue oxygen levels were not reduced with labetalol treatment, with a small but significant elevation in pO2 seen in the treated animals in the 24 hours after stroke. Treated and Untreated rats showed a similar impairment after stroke in terms of neurological score, functional outcome and infarct volume (274±26 mm3 vs Untreated 256±11 mm3).Treating post‐stroke hypertension does not appear to have a major impact on the functional recovery from stroke in rats with pre‐existing hypertension. Future studies will examine the impact of blood pressure lowering in rats already receiving treatment for pre‐existing hypertension, and of treatment to normotensive BP levels in SH rats to mimic the clinical situation of ‘undiagnosed pre‐existing hypertension’.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Renal Mechanism for Regulation of Blood Pressure by the Circadian Clock Protein PER1
Authors: Douma Lauren G. , Holzworth Meaghan , Solocinski Kristen , Cheng Kit‐Yan , Masten Sarah , Lynch I Jeanette , Cain Brian D. , Wingo Charles S. , Gumz Michelle L. 
Published: June 2021

Work from our lab suggests that the clock protein PER1 is critical for maintaining the circadian rhythm of blood pressure (BP). BP is highest during the active phase of the day whereas during the rest period BP dips at least 10%. Individuals that do not experience the dip are termed “non‐dippers.” Non‐dipping hypertension is associated with an increased risk of cardiovascular disease. The mechanisms underlying non‐dipping hypertension are not understood. Male C57BL/6J Per1 KO mice develop non‐dipping hypertension on a high‐salt diet plus mineralocorticoid treatment (HS/DOCP). Sodium (Na) handling by the kidney has large effects on blood volume and BP. Excretion of Na also demonstrates a circadian pattern with a peak of excretion during active periods. We hypothesized that Per1 contributes to circadian regulation of BP via a renal Na handling‐dependent mechanism. To test this hypothesis, we treated WT and Per1 KO mice housed in metabolic cages with a normal salt diet or HS/DOCP. We measured changes in timed urinary Na excretion using flame photometry. The night:day ratio of Na in the urine of Per1 KO mice was decreased compared to WT (4x vs. 7x, P<0.001, n=6 per group). ELISA was used to measure the fold increase of urinary endothelin‐1 (ET‐1) in response to HS/DOCP treatment. Per1 KO mice exhibited a higher fold increase of ET‐1 compared to WT with HS/DOCP (5.9x vs 3.6x, P<0.01, n=9 WT, 11 KO). Using real‐time quantitative PCR, we determined that the expression of Na handling genes was altered in the KO mice on HS/DOCP. ET‐1 was upregulated in the cortex of Per1 KO mice on HS/DOCP treatment (P<0.01, n=6 per group). This upregulation was not present in WT mice on HS/DOCP. Nitric oxide synthase 1 (NOS1), a negative regulator of Na reabsorption, was significantly downregulated in Per1 KO medulla on HS/DOCP (P<0.05, n=6 per group). Preliminary data from the first distal‐nephron specific Per1 KO mice also shows an inappropriate increase in expression of the epithelial Na channel α subunit (αENaC) and the Na chloride cotransporter (NCC) relative to control mice. These results support our hypothesis that Per1 mediates control of circadian BP rhythms via the regulation of renal Na transport genes, specifically in the distal nephron of the kidney. These findings have implications for understanding the etiology of non‐dipping hypertension and the subsequent development of novel therapies for this dangerous pathophysiological condition.Support or Funding InformationR01DK109570; R21AG052861; American Heart Association Grant‐in‐aid; Gatorade Trust Fund, Division of Nephrology, Department of Medicine, University of FloridaThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.