Unlocking Aspirin's Chemopreventive Activity: Role of Irreversibly Inhibiting Platelet Cyclooxygenase-1.

The mechanism by which aspirin consumption is linked to significant reductions in the incidence of multiple forms of cancer and metastatic spread to distant tissues, resulting in increased cancer patient survival is not well understood. In this study, using colon cancer as an example, we provide both in vitro (cell culture) and in vivo (chemically induced mouse model of colon cancer) evidence that this profound antineoplastic action may be associated with aspirin's ability to irreversibly inhibit COX-1-mediated platelet activation, thereby blocking platelet-cancer cell interactions, which promote cancer cell number and invasive potential. This process may be driven by platelet-induced epithelial-mesenchymal transition (EMT), as assessed using confocal microscopy, based upon changes in cell morphology, growth characteristics and fibronectin expression, and biochemical/molecular analysis by measuring changes in the expression of the EMT markers; vimentin, β-catenin, and SNAIL.

Are Temporal Differences in GDNF and NOS Isoform Induction Contributors to Neurodegeneration? A Fluorescence Microscopy-Based Study.

Background: Specific factors in Parkinson's disease have become targets as to their protective and degenerative effects. We have demonstrated that cytokines and PD-CSF detrimentally affect microglia and astrocyte growth. While glial cell-derived neurotrophic factor (GDNF) has been recognized as a possible neuron-rescue agent, nitric oxide synthase (NOS) has been implicated in neurodegenerative processes.

Inflammatory cells and cytokines in the olfactory bulb of a rat model of neuroinflammation; insights into neurodegeneration?

This study examined inflammatory cell and cytokine production in brain tissue from a lipopolysaccharide (LPS)-treated rat model that mimics many of the neuropathologic changes associated with neurodegenerative diseases We also monitored the appearance of a glial cell line-derived neurotrophic factor (GDNF) and circulating nitric oxide (NO) levels, as well as an immune system-associated cells in a selected area of the brain, the olfactory lobe. The studies were based on the hypothesis that LPS treatment stimulates temporal changes within the brain and that these responses include immune cell recruitment, increased tissue levels of immune modulating cytokines and NO, as well as greater glial cell activation resulting in increased production of GDNF. As previously reported by other investigators, our animal model of systemic LPS treatment leads to an increase in the concentrations of circulating cytokines, including TNF-α, IL-Iβ, and IL-6, with a maximum response 6 h post LPS administration.

Modification of a volume-overload heart failure model to track myocardial remodeling and device-related reverse remodeling.

Purpose. To provide an ovine model of ventricular remodeling and reverse remodeling by creating congestive heart failure (CHF) and then treating it by implanting a left ventricular assist device (LVAD). Methods.

Alterations in content and localization of defensins in rat ileum and jejunum following ischemia-reperfusion. Specific peptides, in specific places, for specific jobs?

Objective: To determine alterations in quantities and distributions of natural antimicrobials following ischemia-reperfusion injury. We hypothesized that these compounds would be upregulated in areas of small intestine where changes in permeability and cellular disruption were likely and where protective mechanisms would be initiated.

Methods: Rats with ischemia-reperfusion underwent superior mesenteric artery clamping and reperfusion.

CSF from Parkinson disease patients differentially affects cultured microglia and astrocytes.

Background: Excessive and abnormal accumulation of alpha-synuclein (α-synuclein) is a factor contributing to pathogenic cell death in Parkinson's disease. The purpose of this study, based on earlier observations of Parkinson's disease cerebrospinal fluid (PD-CSF) initiated cell death, was to determine the effects of CSF from PD patients on the functionally different microglia and astrocyte glial cell lines. Microglia cells from human glioblastoma and astrocytes from fetal brain tissue were cultured, grown to confluence, treated with fixed concentrations of PD-CSF, non-PD disease control CSF, or control no-CSF medium, then photographed and fluorescently probed for α-synuclein content by deconvolution fluorescence microscopy.

Reduced volume of the putamen in REM sleep behavior disorder patients.

Objective: The purpose of this study was to quantify volumes of specific subcortical gray matter nuclei implicated in Parkinson's disease (PD) as a preliminary step for identifying a non-invasive clinical biomarker for PD. We hypothesized that REM sleep behavior disorder (RBD) patients, at risk for developing PD, will demonstrate a pattern of neuronal degeneration reflected in reduced striatal volumes on T1-weighted MRI.

Methods: We compared measures of RBD patients confirmed by polysomnography (PSG) with groups of age/gender-matched Control subjects and early PD (EPD) patients (Hoehn & Yahr < 2).

Interference of hawthorn on serum digoxin measurements by immunoassays and pharmacodynamic interaction with digoxin.

Context: Hawthorn is an herb indicated for treating cardiac illness. Because a patient taking digoxin may also take hawthorn, we investigated potential interference of hawthorn in serum digoxin measurements using immunoassays as well as pharmacodynamic interaction between hawthorn and digoxin. Hawthorn contains alkaloids that are structurally similar to digoxin and may interfere with serum digoxin measurement using immunoassays.

Upregulation of defensins in burn sheep small intestine.

Objective: The aim of this study was to visualize and localize the sheep antimicrobials, beta-defensins 1, 2, and 3, (SBD-1, SBD-2, SBD-3), sheep neutrophil defensin alpha (SNP-1), and the cathelicidin LL-37 in sheep small intestine after burn injury, our hypothesis being that these compounds would be upregulated in an effort to overcome a compromised endothelial lining. Response to burn injury includes the release of proinflammatory cytokines and systemic immune suppression that, if untreated, can progress to multiple organ failure and death, so protective mechanisms have to be initiated and implemented.

Methods: Tissue sections were probed with antibodies to the antimicrobials and then visualized with fluorescently labeled secondary antibodies and subjected to fluorescence deconvolution microscopy and image reconstruction.

An inducible cartilage oligomeric matrix protein mouse model recapitulates human pseudoachondroplasia phenotype.

Cartilage oligomeric matrix protein (COMP) is a pentameric extracellular protein expressed in cartilage and other musculoskeletal tissues. Mutations in the COMP gene cause pseudoachondroplasia (PSACH), a severe dwarfing condition that has a growth plate chondrocyte pathology. PSACH is characterized by intracellular retention of COMP and other extracellular matrix (ECM) proteins, which form an ordered matrix within large rough endoplasmic reticulum cisternae.

Stanniocalcin-1 suppresses superoxide generation in macrophages through induction of mitochondrial UCP2.

Mammalian STC1 decreases the mobility of macrophages and diminishes their response to chemokines. In the current experiments, we sought to determine the impact of STC1 on energy metabolism and superoxide generation in mouse macrophages. STC1 decreases ATP level in macrophages but does not affect the activity of respiratory chain complexes I-IV.

Do binucleate cardiomyocytes have a role in myocardial repair? Insights using isolated rodent myocytes and cell culture.

Neonatal and adult cardiomyocytes were isolated from rat hearts. Some of the adult myocytes were cultured to allow for cell dedifferentiation, a phenomenon thought to mimic cell changes that occur in stressed myocardium, with myocytes regressing to a fetal pattern of metabolism and stellate neonatal shape.Using fluorescence deconvolution microscopy, cells were probed with fluorescent markers and scanned for a number of proteins associated with ion control, calcium movements and cardiac function.

Fluorescence microscopy and 3D image reconstruction of cytokine initiated disruption of the Parkinson disease associated proteins alpha-synuclein, tau and ubiquitin in cultured glial cells.

Human derived glioblastoma cells were cultured and treated with cytokines interleukin-6 (IL6), tumor necrosis factor alpha (TNF) and interferon-gamma (IFN) and imaged by fluorescence deconvolution microscopy to localize alpha-synuclein, tau and ubiquitin. Exposures were for short (2 h) and prolonged times (up to 96 h), with doses at both low (10 ng/ml), and high (100 ng/ml) concentrations. Further experiments used additive doses up to 200 ng/ml (2 x 100 ng), mimicking a super-infection state.

A comparison of the effects of commercially available hawthorn preparations on calcium transients of isolated cardiomyocytes.

We studied the potential cardiac effects of two alcohol extracts of commercially available hawthorn using rat cardiomyocytes and measuring calcium transients by real-time fluorescence spectrophotometry. One preparation was a blend of hawthorn flowers, leaves, and berries (extract #1), and the other (extract #2) was from a "berries-only" preparation. Fluorescent images and calcium transients were acquired concurrently.

Left ventricular unloading before reperfusion reduces endothelin-1 release and calcium overload in porcine myocardial infarction.

Objectives: The aim of this study was to test the hypothesis that after an acute myocardial infarction, endothelin-1 release with subsequent calcium overload is a mediator of myocardial reperfusion injury, which can be inhibited, in part, by left ventricular unloading immediately before reperfusion. We recently have reported that left ventricular unloading before reperfusion reduces infarct size after acute myocardial infarction. However, the biologic mechanisms of infarct salvage in unloaded hearts subjected to ischemia/reperfusion remain undefined.

Location and density of alpha- and beta-adrenoreceptor sub-types in myocardium after mechanical left ventricular unloading.

Background: We hypothesized that not all subtypes of alpha- and beta-adrenoreceptors undergo similar upregulation and redistribution in human myocardium after mechanical unloading with an assist device.

Methods: We obtained core biopsy samples of the left ventricle in 19 patients before and after removal of a Jarvik or Thoratec left ventricular assist device (LVAD) to study the effect of mechanical unloading on the distribution of alpha- and beta-adrenoreceptors. Fresh, embedded tissue sections were incubated with receptor blockers and antibodies before the fluorescent labeling of receptors.

Cytokines disrupt intracellular patterns of Parkinson's disease-associated proteins alpha-synuclein, tau and ubiquitin in cultured glial cells.

The purpose of this study was to determine the effects of specific proinflammatory cytokines interleukin-6 (Il-6), interleukin-1beta (Il-1beta), interferon-gamma (IFN), and tumor necrosis factor-alpha (TNFalpha), on content and distribution of alpha-synuclein (alpha-synuclein), tau and ubiquitin in human derived cultured glial cells. Exposure paradigms mimicked acute (2 h), intermediate (18 h) and prolonged time frames (96 h); consisting of single or repeated low doses (10 ng/ml) or high doses (50 ng/ml), consistent with either mild or serious systemic infectious/inflammatory responses. Images of intracellular protein content and distribution were reconstructed from emission patterns generated by fluorescence deconvolution microscopy.

Nuclear localization of HBD-1 in human keratinocytes.

Objective: Human defensins and cathelicidins are a family of cationic antimicrobial peptides (AMPs), which play multiple roles in both innate and adaptive immune systems. They have direct antimicrobial activity against several microorganisms including burn pathogens. The majority of components of innate and adaptive immunity either express naturally occurring defensins or are otherwise chemoattracted or functionally affected by them.

Cardiovascular distribution of the calcium sensing receptor before and after burns.

Due to up-regulation of the parathyroid gland calcium-sensing receptor (CaR), burned children have hypocalcemic hypoparathyroidism, and decreased myocardial contractility. Our aim was to localize the CaR in the heart and measure receptor density changes due to burns. Heart and aorta samples from sheep subjected to 40% burn or sham conditions were probed for CaR via fluorescence microscopy.

Oleandrin produces changes in intracellular calcium levels in isolated cardiomyocytes: a real-time fluorescence imaging study comparing adult to neonatal cardiomyocytes.

Oleanders are common, hardy shrubs that grow throughout the southern United States. They contain cardiotonic steroids formed from cardenolides and bufadienolides, making the plant poisonous to both animals and humans. Aliquots of both commercially available oleander and fresh oleander extracts were prepared.

Unique matrix structure in the rough endoplasmic reticulum cisternae of pseudoachondroplasia chondrocytes.

Mutations in cartilage oligomeric matrix protein (COMP) cause two skeletal dysplasias, pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED/EDM1). Because COMP exists as a homopentamer, only one mutant COMP subunit may result in an abnormal complex that is accumulated in expanded rough endoplasmic reticulum (rER) cisternae, a hallmark of PSACH. Type IX collagen and matrilin-3 (MATN3), also accumulate in the rER cisternae of PSACH chondrocytes, but it is unknown how mutant COMP interacts with these proteins.

The PLAC1 protein localizes to membranous compartments in the apical region of the syncytiotrophoblast.

PLAC1 is a trophoblast-specific gene that maps to a locus on the X-chromosome important to placental development. We have previously shown that PLAC1 gene expression is linked to trophoblast differentiation. The objective of this study was to define the localization of the PLAC1 polypeptide as a prerequisite to understanding its function.

Stanniocalcin-1 regulates endothelial gene expression and modulates transendothelial migration of leukocytes.

The mammalian counterpart of the fish calcium-regulating hormone stanniocalcin-1 (STC1) inhibits monocyte chemotactic protein-1- and stromal-derived factor-1alpha (SDF-1alpha)-mediated chemotaxis and diminishes chemokinesis in macrophage-like RAW264.7 and U937 cells in a manner that may involve attenuation of the intracellular calcium signal. STC1 is strongly induced in the kidney following obstructive injury.

Ginseng: Cardiotonic in adult rat cardiomyocytes, cardiotoxic in neonatal rat cardiomyocytes.

Ginsengs are widely used to improve cardiac health and circulation. Loosely termed as ginsengs, Asian (Panax), Siberian and Ashwagandha (Indian Ginseng) Indian ginsengs are prepared from different plants. We tested the popular belief of cardiotonic effects of ginsengs using both neonatal and adult rat cardiomyocytes, comparing extracts from the three ginsengs.

Reversal of myocyte hypertrophy by ventricular unloading: cardiac improvement without adrenergic receptor up-regulation and relocalization.

In previous studies, we found that the improved contractile ability of cardiac myocytes from patients who have had left ventricular assist device (LVAD) support was due to a number of beneficial changes, most notably in calcium handling (increased sarcoplasmic reticulum calcium binding and uptake), improved integrity of cell membranes due to phospholipid reconstruction (reduced lysophospholipid content), and an upregulation of adrenoreceptors (increased adrenoreceptor numbers). However, in the case presented here, there was no increase in adrenoreceptor number, which is something that we usually find in core tissue at the time of LVAD removal or organ transplantation; also, there was no homogeneous postassist device receptor distribution. However, the patient was well maintained for 10 months following LVAD implantation, until a donor organ was available, regardless of the lack of adrenoreceptor improvement.