Am J Physiol Heart Circ Physiol
April 2016
Studies of myocardial aging are complex and the mechanisms involved in the deterioration of ventricular performance and decreased functional reserve of the old heart remain to be properly defined. We have studied a colony of beagle dogs from 3 to 14 yr of age kept under a highly regulated environment to define the effects of aging on the myocardium. Ventricular, myocardial, and myocyte function, together with anatomical and structural properties of the organ and cardiomyocytes, were evaluated.
View Article and Find Full Text PDFObjective: Extravasation of circulating cancer cells is an important step of the metastatic cascade and a potential target for anti-cancer strategies based on vasoprotective drugs. Reports on anti-cancer effects of fenofibrate (FF) prompted us to analyze its influence on the endothelial barrier function during prostate cancer cell diapedesis.
Research Design And Methods: In vitro co-cultures of endothelial cells with cancer cells imitate the 'metastatic niche' in vivo.
Rationale: Hypoxia favors stem cell quiescence, whereas normoxia is required for stem cell activation, but whether cardiac stem cell (CSC) function is regulated by the hypoxic/normoxic state of the cell is currently unknown.
Objective: A balance between hypoxic and normoxic CSCs may be present in the young heart, although this homeostatic control may be disrupted with aging. Defects in tissue oxygenation occur in the old myocardium, and this phenomenon may expand the pool of hypoxic CSCs, which are no longer involved in myocyte renewal.
Background: Little is known about the function of inositol 1,4,5-trisphosphate receptors (IP3Rs) in the adult heart experimentally. Moreover, whether these Ca(2+) release channels are present and play a critical role in human cardiomyocytes remains to be defined. IP3Rs may be activated after Gαq-protein-coupled receptor stimulation, affecting Ca(2+) cycling, enhancing myocyte performance, and potentially favoring an increase in the incidence of arrhythmias.
View Article and Find Full Text PDFThe formation of aqueous intercellular channels mediating gap junctional intercellular coupling (GJIC) is a canonical function of connexins (Cx). In contrast, mechanisms of GJIC-independent involvement of connexins in cancer formation and metastasis remain a matter of debate. Because of the role of Cx43 in the determination of carcinoma cell invasive potential, we addressed the problem of the possible Cx43 involvement in early prostate cancer invasion.
View Article and Find Full Text PDFIn the present study, we investigated the effects of fenofibrate on the invasive potential of DU-145 human prostate cancer cells in the context of gap junctional intercellular coupling and the formation of reactive oxygen species. Time-lapse analyses of cell motility, accompanied by tests of cell viability, membrane microviscosity, reactive oxygen species accumulation and the function of gap junctional protein connexin 43 were performed in monolayer cultures of DU-145 cells following fenofibrate administration. Fenofibrate inhibited the motility of DU-145 cells and attenuated gap junctional intercellular coupling in a manner independent of its effects on cell viability, PPARα activation and cell membrane micro-viscosity.
View Article and Find Full Text PDFCell Mol Biol Lett
September 2011
Published data concerning the effects of hypertonicity on cell motility have often been controversial. The interpretation of results often rests on the premise that cell responses result from cell dehydration, i.e.
View Article and Find Full Text PDFObjective: This study evaluates usefulness of CXCR4 overexpression via retroviral transduction in adipose tissue-derived mesenchymal stem cells (AT-MSCs) as a strategy to increase their migration and engraftment ability.
Materials And Methods: AT-MSCs were isolated from lipoaspirates from human healthy donors with liberase 3. Cells were transduced with retroviral vector carrying either CXCR4 or green fluorescent protein (GFP) complementary DNA, and neo-resistant colonies were selected and used in experiments.
Background: Glioblastomas are characterized by rapid cell growth, aggressive CNS infiltration, and are resistant to all known anticancer regimens. Recent studies indicate that fibrates and statins possess anticancer potential. Fenofibrate is a potent agonist of peroxisome proliferator activated receptor alpha (PPARalpha) that can switch energy metabolism from glycolysis to fatty acid beta-oxidation, and has low systemic toxicity.
View Article and Find Full Text PDFEph receptors are the largest known subfamily of receptor tyrosine kinases. They interact with membrane-bound proteins called ephrins. Recently, an increasing body of evidence shows that ephrins and Eph receptors are involved in pathological processes such as carcinogenesis.
View Article and Find Full Text PDFTumour cells can efficiently respond to numerous factors affecting their motility. However, the role of substrata topography in the regulation of cancer cell motility has been quantitatively studied in only a few cases. We demonstrated that human (DU-145) and rat (MAT-LyLu and AT-2) prostate cancer cells are efficiently contact guided by underlying normal cells when invading surrounding tissues and forming metastases.
View Article and Find Full Text PDFCationic linear poly-cis-isoprenoid prepared from natural plant polyprenol in a mixture with dioleyl phosphatidylethanolamine was found to be an effective lipofection agent for eukaryotic cells. The transfecting activity is related to the poly-cis structure of the polyprenyl chain.
View Article and Find Full Text PDFThe results of several experimental studies have shown that ascorbic acid inhibits tumor growth and metastasis. Ascorbic acid is an antioxidant that acts as a scavenger for a wide range of reactive oxygen species (ROS). Both tumour metastasis and cell migration have been correlated with the intracellular ROS level, so it was postulated that the inhibitory effect of ascorbic acid derivatives on cell motility may be caused by scavenging of ROS.
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