ABSTRACT
Pyruvate carboxylase (PC) is a mitochondrial, biotin-containing enzyme catalyzing the ATP-dependent synthesis of oxaloacetate from pyruvate and bicarbonate, with a critical anaplerotic role in sustaining the brain metabolism. Based on the studies performed on animal models, PC expression was assigned to be glia-specific. To study PC distribution among human neural cells, we probed the cultured human astrocytes and brain sections with antibodies against PC. Additionally, we tested the importance of PC for the viability of cultured human astrocytes by applying the PC inhibitor 3-chloropropane-1,2-diol (CPD). Our results establish the expression of PC in mitochondria of human astrocytes in culture and brain tissue and also into a subpopulation of the neurons in situ. CPD negatively affected the viability of astrocytes in culture, which could be partially reversed by supplementing media with malate, 2-oxoglutarate, citrate, or pyruvate. The provided data estimates PC expression in human astrocytes and neurons in human brain parenchyma. Furthermore, the enzymatic activity of PC is vital for sustaining the viability of cultured astrocytes.
Subject(s)
Astrocytes , Pyruvate Carboxylase , Animals , Humans , Pyruvate Carboxylase/metabolism , Astrocytes/metabolism , Pyruvic Acid/metabolism , Brain/metabolism , Neurons/metabolismABSTRACT
Numerous pathological changes of subcellular structures are characteristic hallmarks of neurodegeneration. The main research has focused to mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomal networks as well as microtubular system of the cell. The sequence of specific organelle damage during pathogenesis has not been answered yet. Exposition to rotenone is used for simulation of neurodegenerative changes in SH-SY5Y cells, which are widely used for in vitro modelling of Parkinson´s disease pathogenesis. Intracellular effects were investigated in time points from 0 to 24 h by confocal microscopy and biochemical analyses. Analysis of fluorescent images identified the sensitivity of organelles towards rotenone in this order: microtubular cytoskeleton, mitochondrial network, endoplasmic reticulum, Golgi apparatus and lysosomal network. All observed morphological changes of intracellular compartments were identified before alphaS protein accumulation. Therefore, their potential as an early diagnostic marker is of interest. Understanding of subcellular sensitivity in initial stages of neurodegeneration is crucial for designing new approaches and a management of neurodegenerative disorders.
Subject(s)
Microtubules/pathology , Mitochondria/pathology , NADPH Oxidases/metabolism , Neuroblastoma/complications , Neurodegenerative Diseases/pathology , Rotenone/toxicity , Apoptosis , Cell Line, Tumor , Cell Survival , Humans , Insecticides/toxicity , Microtubules/drug effects , Microtubules/metabolism , Mitochondria/drug effects , Mitochondria/metabolism , Neurodegenerative Diseases/etiology , Neurodegenerative Diseases/metabolismABSTRACT
Parkinson's disease (PD) is most commonly manifested by the presence of motor symptoms. However, non-motor symptoms occur several years before the onset of motor symptoms themselves. Hallmarks of dysfunction of the respiratory system are still outside the main focus of interest, whether by clinicians or scientists, despite their indisputable contribution to the morbidity and mortality of patients suffering from PD. In addition, many of the respiratory symptoms are already present in the early stages of the disease and efforts to utilize these parameters in the early diagnosis of PD are now intensifying. Mechanisms that lead to the development and progression of respiratory symptoms are only partially understood. This review focuses mainly on the comparison of respiratory problems observed in clinical studies with available findings obtained from experimental animal models. It also explains pathological changes observed in non-neuronal tissues in subjects with PD.
Subject(s)
Parkinson Disease/epidemiology , Parkinson Disease/physiopathology , Respiration Disorders/epidemiology , Respiration Disorders/physiopathology , Respiratory Mechanics/physiology , Animals , Humans , Neurodegenerative Diseases/diagnosis , Neurodegenerative Diseases/epidemiology , Neurodegenerative Diseases/physiopathology , Parkinson Disease/diagnosis , Respiration Disorders/diagnosisABSTRACT
Parkinson's disease (PD) is currently the second most common neurodegenerative disorder in the world. Major features of cell pathology of the disease include the presence of cytoplasmic inclusions called Lewy bodies, which are composed of aggregated proteins. The presence of Lewy's body is associated with more advanced stages of the disease when considering irreversible changes. Precise identification of the disease stage at a cellular level presents the critical tool in developing early diagnostics and/or prevention of PD. The aim of our work is to introduce sensitive microscopic analysis in living cells, focused on initial intracellular changes and thus capable to detect earlier stages of the disease.
