Zinc is involved in the expression and function of various transcription factors, including the hypoxia-inducible factor-1 (HIF-1). HIF-1 and its target gene endothelin-1 (ET-1) are activated by intermittent hypoxia (IH), one of the main consequences of obstructive sleep apnea (OSA), and both play a key role in the cardiovascular consequences of IH. Because OSA and IH are associated with zinc deficiency, we investigated the effect of zinc deficiency caused by chelation on the HIF-1/ET-1 pathway and its functional consequences in endothelial cells.
View Article and Find Full Text PDFZinc, an essential micronutrient, has a cancer preventive role. Zinc deficiency has been shown to contribute to the progression of esophageal cancer. Orai1, a store-operated Ca entry (SOCE) channel, was previously reported to be highly expressed in tumor tissues removed from patients with esophageal squamous cell carcinoma (ESCC) with poor prognosis, and elevation of its expression contributes to both hyperactive intracellular Ca oscillations and fast cell proliferation in human ESCC cells.
View Article and Find Full Text PDFAs a nutritionally essential metal ion, zinc (Zn) not only constitutes a structural element for more than 3000 proteins but also plays important regulatory functions in cellular signal transduction. Zn homeostasis is tightly controlled by regulating the flux of Zn across cell membranes through specific transporters, i.e.
View Article and Find Full Text PDFBackground: Obstructive sleep apnea (OSA) is a highly prevalent disease and a risk factor for myocardial infarction expansion in humans. Intermittent hypoxia (IH) is known to be the most important OSA feature in terms of cardiovascular morbi-mortality. Since ER stress and HIF-1 are known to be involved in cardiomyocyte life or death, this study investigates the role of ER stress on HIF-1 activation in myocardial susceptibility to ischemia-reperfusion (I/R) induced by IH.
View Article and Find Full Text PDFZinc is an essential trace element that participates in a wide range of biological functions, including wound healing. Although Zn(2+) deficiency has been linked to compromised wound healing and tissue repair in human diseases, the molecular mechanisms underlying Zn(2+)-mediated tissue repair remain unknown. Our previous studies established that MG53, a TRIM (tripartite motif) family protein, is an essential component of the cell membrane repair machinery.
View Article and Find Full Text PDFCalcium (Ca(2+)) and magnesium (Mg(2+)) are important metal elements that regulate a variety of cellular processes such as proliferation, migration, and apoptosis, in cancer cells. Among the ionic channels mediating intracellular entry, the transient receptor potential melastatin type 7 (TRPM7) channel is of particular interest, it being a non-selective, cationic channel mediating both Ca(2+) and Mg(2+) influx. TRPM7 is highly expressed in a number of human cancer tissues and cell lines.
View Article and Find Full Text PDFChronic intermittent hypoxia (IH), a major component of obstructive sleep apnea (OSA), contributes to the high risk of cardiovascular morbidity. We have previously demonstrated that IH-induced oxidative stress is involved in the hypertension and in the hypersensitivity to myocardial infarction. However, the mechanisms underlying these cardiovascular alterations are still unclear, as well as the role of potential protective treatment.
View Article and Find Full Text PDFZinc is a vital element in maintaining the normal structure and physiology of cells. The fact that it has an important role in states of cardiovascular diseases has been studied and described by several research groups. It appears to have protective effects in coronary artery disease and cardiomyopathy.
View Article and Find Full Text PDFThe zinc(II) ion has recently been implicated in a number of novel functions and pathologies in loci as diverse as the brain, retina, small intestine, prostate, heart, pancreas, and immune system. Zinc ions are a required nutrient but elevated concentrations are known to kill cells in vitro. Paradoxical observations regarding zinc's effects have appeared frequently in the literature, and often their physiological relevance is unclear.
View Article and Find Full Text PDFThe recent discovery of zinc signals and their essential role in the redox signaling network implies that zinc homeostasis and the function of zinc-containing proteins are probably altered as a result of oxidative stress, suggesting new targets for pharmacological intervention. We hypothesized that the level of intracellular labile zinc is changed in hearts subjected to ischemia/reperfusion (I/R) and investigated whether the maintenance of myocardial zinc status protected heart functions. Using fluorescent imaging, we demonstrated decreased levels of labile zinc in the I/R hearts.
View Article and Find Full Text PDFZinc plays a vital role in various cellular functions. Zinc deprivation is associated with severe disorders related to growth, maturation, and stress responses. In the heart, zinc affects differentiation and regeneration of cardiac muscle, cardiac conductance, acute stress responses, and recovery of heart transplants.
View Article and Find Full Text PDFThe two extremes of redox stress imposed on cardiac tissue under ischemia and reperfusion change the redox potential of the cells and affect numerous redox-sensitive molecules, including the ones involved in intracellular communication. Protein kinase C (PKC), a key signalling kinase, is one of those subject to redox control. Activation of PKC by oxidation represents a new paradigm of the alternate signalling principle.
View Article and Find Full Text PDFZinc is a structural component of many regulatory molecules including transcription factors and signaling molecules. We report that two alternate signaling pathways of protein kinase C (PKC) activation involving either the lipid second messengers (diacylglycerol and its mimetics, the phorbol esters) or reactive oxygen converge at the zinc finger of the regulatory domain. They all trigger the release of zinc ions.
View Article and Find Full Text PDFThe present study highlights retinoids as modulators of c-Raf kinase activation by UV light. Whereas a number of retinoids, including retinol, 14-hydroxyretroretinol, anhydroretinol (AR), and retinoic acid bound the c-Raf cysteine-rich domain (CRD) with equal affinity in vitro as well as in vivo, they displayed different, even opposing, effects on UV-mediated kinase activation; retinol and 14-hydroxyretroretinol augmented responses, whereas retinoic acid and AR were inhibitory. Oxidation of thiol groups of cysteines by reactive oxygen, generated during UV irradiation, was the primary event in c-Raf activation, causing the release of zinc ions and, by inference, a change in CRD structure.
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