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Metabolic Insults (metabolic + insult)
Selected AbstractsInduction of hypoxia inducible factor-1 attenuates metabolic insults induced by 3-nitropropionic acid in rat C6 glioma cellsJOURNAL OF NEUROCHEMISTRY, Issue 3 2005Ya-Ting Yang Abstract Compromised mitochondrial function in neurons and glia has been observed in several neurodegenerative disorders, including Huntington's disease and Alzheimer's disease. Chemical/hypoxic preconditioning may afford protection against subsequently more severe oxidative damages. In this study, we tested whether induction of hypoxia inducible factor-1 (HIF-1) may exert cytoprotective effects against mitochondrial dysfunction caused by 3-nitropropionic acid (3-NP) in glial cells. Preconditioning of C6 astroglial cells with cobalt chloride, mimosine (MIM), and desferrioxamine (DFO), all of which known to activate HIF-1, significantly attenuated cytotoxicity induced by 3-NP, an irreversible inhibitor of mitochondrial complex II, and antimycin A, a mitochondrial complex III inhibitor. Application of cadmium chloride capable of neutralizing cobalt-induced HIF-1 activation, HIF-specific oligodeoxynucleotide (ODN) decoy, and antisense phosphorothioate ODN against HIF-1, abolished the protective effect mediated by preconditioning with cobalt chloride. Preloading of C6 cells with SN50, PD98059, or SB202190, the respective inhibitor of nuclear factor-,B (NF-,B), p44/p42 extracellular signal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (MAPK), failed to affect the protection afforded by cobalt preconditioning. Taken together, these results suggest that HIF-1 induction secondary to preconditioning with cobalt chloride or iron chelators may mediate the protective effects against metabolic insult induced by the mitochondrial inhibitor 3-NP in C6 astroglial cells. [source] Neuroimaging and Neurologic Complications after Organ TransplantationJOURNAL OF NEUROIMAGING, Issue 2 2007ivkovi ABSTRACT Neurologic complications are common after transplantation and affect 30-60% of transplant recipients. The etiology of most of the posttransplant neurologic disorders is related to the opportunistic infections, both systemic and involving central nervous system (CNS), toxicity of immunosuppressive medications, and the metabolic insult created by the underlying primary disease and the transplant procedure. Neuroimaging studies are one of the key tools in the evaluation and enable early diagnosis of neurologic complications in transplant patients, especially posterior reversible leukoencephalopathy syndrome, central pontine myelinolysis, intracerebral hemorrhage, and fungal and bacterial abscesses. Magnetic resonance imaging (MRI) is the preferred technique, but each of the available neuroimaging techniques offers a unique insight into the pathophysiologic mechanisms underlying neurologic complications of transplantation. The role of neuroimaging in this population includes early detection of calcineurin inhibitor neurotoxicity, opportunistic infections, neoplasia, metabolic disorders, or cerebrovascular diseases. In addition, we can monitor longitudinal progression of disease and treatment response. [source] Plumbagin, a novel Nrf2/ARE activator, protects against cerebral ischemiaJOURNAL OF NEUROCHEMISTRY, Issue 5 2010Tae Gen Son J. Neurochem. (2010) 112, 1316,1326. Abstract Many phytochemicals function as noxious agents that protect plants against insects and other damaging organisms. However, at subtoxic doses, the same phytochemicals may activate adaptive cellular stress response pathways that can protect cells against a variety of adverse conditions. We screened a panel of botanical pesticides using cultured human and rodent neuronal cell models, and identified plumbagin as a novel potent activator of the nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway. In vitro, plumbagin increases nuclear localization and transcriptional activity of Nrf2, and induces the expression of the Nrf2/ARE-dependent genes, such as heme oxygenase 1 in human neuroblastoma cells. Plumbagin specifically activates the Nrf2/ARE pathway in primary mixed cultures from ARE-human placental alkaline phosphatase reporter mice. Exposure of neuroblastoma cells and primary cortical neurons to plumbagin provides protection against subsequent oxidative and metabolic insults. The neuroprotective effects of plumbagin are abolished by RNA interference-mediated knockdown of Nrf2 expression. In vivo, administration of plumbagin significantly reduces the amount of brain damage and ameliorates-associated neurological deficits in a mouse model of focal ischemic stroke. Our findings establish precedence for the identification and characterization of neuroprotective phytochemicals based upon their ability to activate adaptive cellular stress response pathways. [source] Induction of hypoxia inducible factor-1 attenuates metabolic insults induced by 3-nitropropionic acid in rat C6 glioma cellsJOURNAL OF NEUROCHEMISTRY, Issue 3 2005Ya-Ting Yang Abstract Compromised mitochondrial function in neurons and glia has been observed in several neurodegenerative disorders, including Huntington's disease and Alzheimer's disease. Chemical/hypoxic preconditioning may afford protection against subsequently more severe oxidative damages. In this study, we tested whether induction of hypoxia inducible factor-1 (HIF-1) may exert cytoprotective effects against mitochondrial dysfunction caused by 3-nitropropionic acid (3-NP) in glial cells. Preconditioning of C6 astroglial cells with cobalt chloride, mimosine (MIM), and desferrioxamine (DFO), all of which known to activate HIF-1, significantly attenuated cytotoxicity induced by 3-NP, an irreversible inhibitor of mitochondrial complex II, and antimycin A, a mitochondrial complex III inhibitor. Application of cadmium chloride capable of neutralizing cobalt-induced HIF-1 activation, HIF-specific oligodeoxynucleotide (ODN) decoy, and antisense phosphorothioate ODN against HIF-1, abolished the protective effect mediated by preconditioning with cobalt chloride. Preloading of C6 cells with SN50, PD98059, or SB202190, the respective inhibitor of nuclear factor-,B (NF-,B), p44/p42 extracellular signal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (MAPK), failed to affect the protection afforded by cobalt preconditioning. Taken together, these results suggest that HIF-1 induction secondary to preconditioning with cobalt chloride or iron chelators may mediate the protective effects against metabolic insult induced by the mitochondrial inhibitor 3-NP in C6 astroglial cells. [source] Expanding roles for AMP-activated protein kinase in neuronal survival and autophagyBIOESSAYS, Issue 9 2009Jeroen Poels Abstract AMP-activated protein kinase (AMPK) is an evolutionarily conserved cellular switch that activates catabolic pathways and turns off anabolic processes. In this way, AMPK activation can restore the perturbation of cellular energy levels. In physiological situations, AMPK senses energy deficiency (in the form of an increased AMP/ATP ratio), but it is also activated by metabolic insults, such as glucose or oxygen deprivation. Metformin, one of the most widely prescribed anti-diabetic drugs, exerts its actions by AMPK activation. However, while the functions of AMPK as a metabolic regulator are fairly well understood, its actions in neuronal cells only recently gained attention. This review will discuss newly emerged functions of AMPK in neuroprotection and neurodegeneration. Additionally, recent views on the role of AMPK in autophagy, an important catabolic process that is also involved in neurodegeneration and cancer, will be highlighted. [source] |