The Federation of Asian and Oceanian Biochemists and Molecular Biologists, Inc. (FAOBMB) celebrates its Golden Jubilee in 2022. Established in August 1972 as a regional grouping of three national societies of biochemists in Australia, India and Japan, it took the name Federation of Asian and Oceanian Biochemists (FAOB).
View Article and Find Full Text PDFContributions of damaged mitochondria to neuropathologies have stimulated interest in mitophagy. We investigated triggers of neuronal mitophagy by disruption of mitochondrial energy metabolism in primary neurons. Mitophagy was examined in cultured murine cerebellar granule cells after inhibition of mitochondrial respiratory chain by drugs rotenone, 3-nitropropionic acid, antimycin A, and potassium cyanide, targeting complexes I, II, III, and IV, respectively.
View Article and Find Full Text PDFCu/Zn-superoxide dismutase is misfolded in familial and sporadic amyotrophic lateral sclerosis, but it is not clear how this triggers endoplasmic reticulum (ER) stress or other pathogenic processes. Here, we demonstrate that mutant SOD1 (mSOD1) is predominantly found in the cytoplasm in neuronal cells. Furthermore, we show that mSOD1 inhibits secretory protein transport from the ER to Golgi apparatus.
View Article and Find Full Text PDFThe innate immune response to virus must be balanced to eliminate infection yet limit damaging inflammation. A critical arm of the antiviral response is launched by the retinoic acid-inducible-gene I (RIG-I) protein. RIG-I is activated by viral RNA then associates with the mitochondrial antiviral signaling (MAVS) protein to subsequently induce potent inflammatory cytokines.
View Article and Find Full Text PDFNeurons can undergo a diverse range of death responses under oxidative stress, encompassing apoptosis (caspase-dependent, programmed cell death) to various forms of caspase-independent death, including necrosis. We recently showed that primary murine cortical neurons exposed acutely to hydrogen peroxide undergo caspase-independent death, both autophagic cell death and programmed necrosis. To determine how oxidative stress induced by superoxide affects the route to cellular demise, we exposed primary cortical neurons to extended superoxide insult (provided by exogenous xanthine and xanthine oxidase in the presence of catalase).
View Article and Find Full Text PDFMitochondrially mediated apoptosis is characterized by redistribution of proteins from mitochondria to cytoplasm following permeabilization of the outer mitochondrial membrane. We applied flow cytometry to quantify simultaneously the redistribution of two apoptogenic proteins, cytochrome c (cyt c) and Smac/DIABLO (Smac). Mammalian cells were treated with digitonin that selectively permeabilizes the plasma membrane.
View Article and Find Full Text PDFEndoplasmic reticulum (ER) stress is an important pathway to cell death in amyotrophic lateral sclerosis (ALS). We previously demonstrated that ER stress is linked to neurotoxicity associated with formation of inclusions of mutant Cu,Zn-superoxide dismutase 1 (SOD1). Cells bearing mutant inclusions undergo mitochondrial apoptotic signalling.
View Article and Find Full Text PDFBackground: Bacteria of the suborder Corynebacterineae include significant human pathogens such as Mycobacterium tuberculosis and M. leprae. Drug resistance in mycobacteria is increasingly common making identification of new antimicrobials a priority.
View Article and Find Full Text PDFIncreased expression of Hsp72 accompanies differentiation of human neuroblastoma SH-SY5Y cells to neuron-like cells. By modulating cellular levels of Hsp72, we demonstrate here its anti-apoptotic activity both in undifferentiated and neuron-like cells. Thermal preconditioning (43°C for 30 min) induced Hsp72, leading to cellular protection against apoptosis induced by a subsequent treatment with staurosporine.
View Article and Find Full Text PDFPurpose: Terminally differentiated neurones in the central nervous system need to be protected from stress. We ask here whether differentiation of progenitor cells to neurones is accompanied by up-regulation of Hsp72, with acquisition of enhanced thermotolerance.
Materials And Methods: Human neuroblastoma SH-SY5Y cells were propagated in an undifferentiated form and subsequently differentiated into neurone-like cells.
Primary neurons undergo insult-dependent programmed cell death. We examined autophagy as a process contributing to cell death in cortical neurons after treatment with either hydrogen peroxide (H(2)O(2)) or staurosporine. Although caspase-9 activation and cleavage of procaspase-3 were significant following staurosporine treatment, neither was observed following H(2)O(2) treatment, indicating a non-apoptotic death.
View Article and Find Full Text PDFOxidative stress plays a central role in neuronal injury and cell death in acute and chronic pathological conditions. The cellular responses to oxidative stress embrace changes in mitochondria and other organelles, notably endoplasmic reticulum, and can lead to a number of cell death paradigms, which cover a spectrum from apoptosis to necrosis and include autophagy. In Alzheimer's disease, and other pathologies including Parkinson's disease, protein aggregation provides further cellular stresses that can initiate or feed into the pathways to cell death engendered by oxidative stress.
View Article and Find Full Text PDFElderly patients undergoing cardiac surgery are more likely to suffer postoperative heart failure than younger patients. This phenomenon is mirrored by an age-related loss of mitochondrial function and by an in vitro loss of myocardial contractile force following a stress. To examine the possibility that loss of mtDNA integrity may be responsible, we quantified representative age-associated mtDNA mutations (mtDNA(4977) and mtDNA(A3243G)) and mtDNA copy number using quantitative polymerase chain reaction in atrial samples obtained during cardiac surgery.
View Article and Find Full Text PDFNeurones undergo diverse forms of cell death depending on the nature and severity of the stress. These death outcomes are now classified into various types of programmed cell death, including apoptosis, autophagy and necrosis. Each of these pathways can run in parallel and all have mitochondria as a central feature.
View Article and Find Full Text PDFTo characterize neuronal death, primary cortical neurons (C57/Black 6 J mice) were exposed to hydrogen peroxide (H2O2) and staurosporine. Both caused cell shrinkage, nuclear condensation, DNA fragmentation and loss of plasma membrane integrity. Neither treatment induced caspase-7 activity, but caspase-3 was activated by staurosporine but not H2O2.
View Article and Find Full Text PDFGABAergic striatal neurons are compromised in basal ganglia pathologies and we analysed how insult nature determined their patterns of injury and recruitment of the intrinsic mitochondrial pathway during programmed cell death (PCD). Stressors affecting targets implicated in striatal neurodegeneration [3-morpholinylsydnoneimine (SIN-1), 3-nitropropionic acid (3-NP), NMDA, 3,5-dihydroxyphenylglycine (DHPG), and staurosporine (STS)] were compared in cultured GABAergic neurons from murine striatum by analyzing the progression of injury and its correlation with mitochondrial involvement, the redistribution of intermembrane space (IMS) proteins, and patterns of protease activation. Stressors produced PCD exhibiting slow-onset kinetics with time-dependent annexin-V labeling and eventual DNA fragmentation.
View Article and Find Full Text PDFMutations in Cu, Zn-superoxide dismutase 1 (SOD1) are associated with degeneration of motor neurons in the disease, familial amyotrophic lateral sclerosis. Intracellular protein inclusions containing mutant SOD1 (mSOD1) are associated with disease but it is unclear whether they are neuroprotective or cytotoxic. We report here that the formation of mSOD1 inclusions in a motor neuron-like cell line (NSC-34) strongly correlates with apoptosis via the mitochondrial death pathway.
View Article and Find Full Text PDFBackground: Many cancers preferentially meet their energy requirements through the glycolytic pathway rather than via the more efficient oxidative phosphorylation pathway. It is thought that this is an important adaptation in cancer malignancy. We investigated whether use of glycolysis for energy production even in the presence of oxygen (known as the Warburg effect) varied between neuroblastoma cell lines with or without MYCN amplification (a key indicator of poor disease outcome in neuroblastoma).
View Article and Find Full Text PDFIn amyotrophic lateral sclerosis (ALS) non-neuronal cells play key roles in disease etiology and loss of motoneurons via noncell-autonomous mechanisms. Reactive astrogliosis and dysfunctional transporters for L-glutamate [excitatory amino acid transporters, (EAATs)] are hallmarks of ALS pathology. Here, we describe mechanistic insights into ALS pathology involving EAAT-associated homeostasis in response to a destructive milieu, in which oxidative stress and excitotoxicity induce respectively astrogliosis and motoneuron injury.
View Article and Find Full Text PDFMitochondria play a key role in death signaling. The intermembrane space of these organelles contains a number of proteins which promote cell death once they are redistributed to the cytosol. The formation of pores in the outer membrane of mitochondria defines a gateway through which the apoptogenic proteins pass during death signaling.
View Article and Find Full Text PDFExcitotoxicity mediated via the (S)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) subtype of receptor for l-glutamate contributes to various neuropathologies involving acute brain injury and chronic degenerative disorders. In this study, AMPA-induced neuronal injury and staurosporine (STS)-mediated apoptosis were compared in primary neuronal cultures of murine cerebral cortex by analyzing indices up- and downstream of mitochondrial activation. AMPA-mediated apoptosis involved induction of Bax, loss of mitochondrial transmembrane potential (deltapsi(m)), early release of cytochrome c (cyt c), and more delayed release of second mitochondrial activator of caspases (SMAC), Omi, and apoptosis-inducing factor (AIF) with early calpain and minor late activation of caspase 3.
View Article and Find Full Text PDFRotenone and 1-methyl-4-phenylpyridinium produce parkinsonian models and we determined whether their mitochondrially mediated actions differentially redistributed the apoptogenic proteins, apoptosis-inducing factor and cytochrome c. Cultured rat mesencephalic dopamine neurons were exposed to rotenone (30 nM) and 1-methyl-4-phenylpyridinium (300 muM, 24 and 48 h) and apoptosis and mitochondrial redistribution of cytochrome c or apoptosis-inducing factor were quantified. Tyrosine hydroxylase-positive dopamine neurons underwent apoptosis (shrinkage, less neurites) and 40% released apoptosis-inducing factor with rotenone (24 h), whereas cytochrome c release reached this value at 48 h when 70% of cells had released apoptosis-inducing factor-positive.
View Article and Find Full Text PDFMutations in Cu/Zn superoxide dismutase (SOD1) are linked to motor neuron death in familial amyotrophic lateral sclerosis (ALS) by an unclear mechanism, although misfolded SOD1 aggregates are commonly associated with disease. Proteomic analysis of the transgenic SOD1(G93A) ALS rat model revealed significant up-regulation of endoplasmic reticulum (ER)-resident protein-disulfide isomerase (PDI) family members in lumbar spinal cords. Expression of SOD1 mutants (mSOD1) led to an up-regulation of PDI in motor neuron-like NSC-34 cells but not other cell lines.
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