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Brain Research Oct 2009This study used a comparative proteomics approach to identify the effects of the antipsychotic drugs, Chlorpromazine (CPZ), Clozapine (CLZ), and Quetiapine (QTP) on the...
This study used a comparative proteomics approach to identify the effects of the antipsychotic drugs, Chlorpromazine (CPZ), Clozapine (CLZ), and Quetiapine (QTP) on the synaptosomal protein of the cerebral cortex of Sprague-Dawley (SD) rats. The multivariate statistical test partial least squares-discriminant analysis (PLS-DA) was applied to build the models for screening out the variable important plot (VIP). The PLS-DA models were able to distinguish each drug treatment group and the control group; more importantly, the univariate differentially expressed protein spots were capable of being verified by the VIP of the models. The interrelationships among the identified proteins were analyzed using Pearson's correlation analysis and pathway analysis. Through the synaptosome proteome experiments, we established that the energy production of the mitochondrial function and 'Glycolysis/Gluconeogenesis' were involved in the response to antipsychotic medications. Furthermore, the G protein-coupled signal transduction system was also inhibited by antipsychotic medications. The result of our study should contribute to the understanding of the effects of antipsychotic drugs on synaptic function.
Topics: Analysis of Variance; Animals; Antipsychotic Agents; Cerebral Cortex; Chlorpromazine; Clozapine; Dibenzothiazepines; Electrophoresis, Gel, Two-Dimensional; Male; Mass Spectrometry; Multivariate Analysis; Peptide Mapping; Proteome; Proteomics; Quetiapine Fumarate; Rats; Rats, Sprague-Dawley; Signal Transduction; Synaptosomes
PubMed: 19660441
DOI: 10.1016/j.brainres.2009.07.097 -
Nucleic Acids Research May 2000Synaptosome cybrids were used to confirm the presence of heteroplasmic mtDNA sequence variants in the human brain. Synaptosomes contain one to several mitochondria, and...
Synaptosome cybrids were used to confirm the presence of heteroplasmic mtDNA sequence variants in the human brain. Synaptosomes contain one to several mitochondria, and when fused to mtDNA-deficient (rho degrees ) mouse or human cell lines result in viable cybrid cell lines. The brain origin of mouse synaptosome cybrid mtDNAs was confirmed using sequence polymorphisms in the mtDNA COIII, ND3 and tRNA(Arg)genes. The brain origin of the human synaptosome cybrids was confirmed using a rare mtDNA Mbo I polymorphism. Fusion of synaptosomes from the brain of a 35-year-old woman resulted in 71 synaptosome cybrids. Sequencing the mtDNA control region of these cybrid clones revealed differences in the number of Cs in a poly C track between nucleotide pairs (nps) 301 and 309. Three percent of the cybrid clones had mtDNAs with 10 Cs, 76% had nine, 18% had eight and 3% had seven Cs. Comparable results were obtained by PCR amplification, cloning and sequencing of mtDNA control regions directly from the patient's brain tissue, but not when the control region was amplified and cloned from a synaptosome cybrid homoplasmic for a mtDNA with nine Cs. Thus, we have clonally recovered mtDNA control region length variants from an adult human brain without recourse to PCR, and established the variant mtDNAs within living cultured cells. This confirms that some mtDNA heteroplasmy can exist in human neurons, and provides the opportunity to study its functional significance.
Topics: Adult; Animals; Brain; Cell Line; Cloning, Molecular; DNA Primers; DNA, Mitochondrial; DNA, Ribosomal; Female; Genetic Variation; Humans; Hybrid Cells; Membrane Fusion; Mice; Mice, Inbred C57BL; Neurons; Synaptosomes
PubMed: 10773087
DOI: 10.1093/nar/28.10.2164 -
Electrophoresis Apr 2010Synapses play important roles in neurotransmission and neuroplasticity. For an in-depth analysis of the synaptic proteome and phosphoproteome, synaptosomal proteins from...
Synapses play important roles in neurotransmission and neuroplasticity. For an in-depth analysis of the synaptic proteome and phosphoproteome, synaptosomal proteins from whole mouse brain were analyzed by IEF and MS resulting in the largest synaptosome proteome described to date, with 2980 unique proteins identified with two or more peptides. At the same time, 118 synaptosomal phosphoproteins were identified, eight of which are reported for the first time as phosphorylated. Expression of selected proteins in synaptosomes was investigated by Western blot. We demonstrate that IEF is a powerful method to interrogate complex samples such as brain tissue both at the proteome and the phosphoproteome level without the need of additional enrichment for phosphoproteins. The detailed synaptoproteome data set reported here will help to elucidate the molecular complexity of the synapse and contribute to our understanding of synaptic systems biology in health and disease.
Topics: Amino Acid Sequence; Animals; Blotting, Western; Isoelectric Focusing; Isoelectric Point; Mass Spectrometry; Mice; Molecular Sequence Data; Molecular Weight; Nerve Tissue Proteins; Phosphoproteins; Proteome; Proteomics; Synaptosomes
PubMed: 20309889
DOI: 10.1002/elps.200900647 -
Journal of Nanobiotechnology Jan 2021Mitochondrial dysfunction is a critical factor in the onset and progression of neurodegenerative diseases. Recently, mitochondrial transplantation has been advised as an...
BACKGROUND
Mitochondrial dysfunction is a critical factor in the onset and progression of neurodegenerative diseases. Recently, mitochondrial transplantation has been advised as an innovative and attractive strategy to transfer and replace damaged mitochondria. Here we propose, for the first time, to use rat brain extracted synaptosomes, a subcellular fraction of isolated synaptic terminal that contains mitochondria, as mitochondrial delivery systems.
RESULTS
Synaptosome preparation was validated by the presence of Synaptophysin and PSD95. Synaptosomes were characterized in terms of dimension, zeta potential, polydispersity index and number of particles/ml. Nile Red or CTX-FITCH labeled synaptosomes were internalized in LAN5 recipient cells by a mechanism involving specific protein-protein interaction, as demonstrated by loss of fusion ability after trypsin treatment and using different cell lines. The loading and release ability of the synaptosomes was proved by the presence of curcumin both into synaptosomes and LAN5 cells. The vitality of mitochondria transferred by Synaptosomes was demonstrated by the presence of Opa1, Fis1 and TOM40 mitochondrial proteins and JC-1 measurements. Further, synaptosomes deliver vital mitochondria into the cytoplasm of neuronal cells as demonstrated by microscopic images, increase of TOM 40, cytochrome c, Hexokinase II mitochondrial proteins, and presence of rat mitochondrial DNA. Finally, by using synaptosomes as a vehicle, healthy mitochondria restored mitochondrial function in cells containing rotenone or CCCp damaged mitochondria.
CONCLUSIONS
Taken together these results suggest that synaptosomes can be a natural vehicle for the delivery of molecules and organelles to neuronal cells. Further, the replacement of affected mitochondria with healthy ones could be a potential therapy for treating neuronal mitochondrial dysfunction-related diseases.
Topics: Animals; Cytochromes c; DNA, Mitochondrial; Drug Delivery Systems; Homeostasis; Male; Membrane Potentials; Mitochondria; Protein Interaction Domains and Motifs; Rats; Subcellular Fractions; Synaptosomes
PubMed: 33407593
DOI: 10.1186/s12951-020-00748-6 -
The Biochemical Journal Apr 1981The ionophore valinomycin inhibited adult and neonatal synaptosome fraction protein synthesis with half-maximal inhibition at approximately 10nM. Valinomycin had no...
The ionophore valinomycin inhibited adult and neonatal synaptosome fraction protein synthesis with half-maximal inhibition at approximately 10nM. Valinomycin had no effect on [3H]leucine uptake into synaptosomes at high or low external [K+]. Synaptosome-fraction protein synthesis was dependent on [K+]e reaching a maximum at 25mM-K+. Valinomycin inhibition of protein synthesis was not reversed at high [K+]e. Valinomycin failed to influence the intrasynaptosomal [K+] even at zero [K+]e. A significant increase in State-4 respiration of synaptosomal fractions was found at 5nM-valinomycin with a decrease in the respiratory control index. At these concentrations of valinomycin there was no inhibition of the ADP-stimulated (State 3) respiration rate. Valinomycin had no effect on cerebral microsomal protein synthesis in vitro, which was inhibited by puromycin (100 micrograms/ml) or the absence of ATP. Valinomycin, 2,4-dinitrophenol and KCN inhibition of protein synthesis was not reversed by added ATP, suggesting impermeability of the membrane to ATP. Valinomycin induced a rapid fall in synaptosome ATP content not observed with atractylate or ouabain. Valinomycin inhibition of protein synthesis under these conditions is secondary to uncoupling of mitochondrial oxidative phosphorylation with a subsequent decrease in intraterminal ATP necessary for translation.
Topics: Adenosine Triphosphate; Amino Acids; Animals; Depression, Chemical; Female; In Vitro Techniques; Male; Oxidative Phosphorylation; Oxygen Consumption; Potassium; Protein Biosynthesis; Rats; Synaptosomes; Valinomycin
PubMed: 7306072
DOI: 10.1042/bj1960025 -
FEMS Microbiology Letters Nov 1990Purified toxin and its subunits from Clostridium botulinum type B were labeled with 125iodine and binding of them to rat brain synaptosomes was studied. Labeled toxin...
Purified toxin and its subunits from Clostridium botulinum type B were labeled with 125iodine and binding of them to rat brain synaptosomes was studied. Labeled toxin and heavy chain were shown to bind to synaptosomes and there was no significant difference in the molar quantity of bound toxin and heavy chain at several concentrations of synaptosomes, whereas labeled light chain did not bind to synaptosomes. The binding of labeled heavy chain to synaptosomes was inhibited by unlabeled toxin and heavy chain to a similar degree as that of labeled toxin. The binding of labeled toxin and heavy chain to synaptosomes were inhibited by a monoclonal antibody which is specific for the heavy chain.
Topics: Animals; Antibodies, Monoclonal; Brain; Clostridium botulinum; Mice; Mice, Inbred BALB C; Synaptosomes; Toxoids
PubMed: 2083835
DOI: 10.1016/0378-1097(90)90311-d -
Neuroscience Letters Oct 2009Formaldehyde (FA) exposure is known to be toxic to central nervous system of mammals. In this paper, we evaluated the aggressive behavior after repetitive inhalative FA...
Formaldehyde (FA) exposure is known to be toxic to central nervous system of mammals. In this paper, we evaluated the aggressive behavior after repetitive inhalative FA exposure to male SD rats, and explored the potential mechanism. The rats, ranging from 160 to 180 g, were randomly designated into the orchiectomized (ORX) group, the control and the inhalative FA treatment groups. Eight rats underwent orchiectomy surgery. Three days after the orchiectomy surgery, the inhalative FA (monitored to be 13.5+/-1.5 ppm) treatment began. We found that the male SD rats, those were exposed to FA showed more aggressive behavior compared to the control. And the ORX rats exhibited less aggressive behavior than the control. Furthermore, the dopamine increased and 5-HT decreased significantly in frontal cortex synaptosome after inhalative FA treatment. It is the first to evaluate aggressive behavior and identified monoamines disturbances in the frontal cortex synaptosome after the repetitive inhalative FA exposure to rodents.
Topics: Aggression; Animals; Biogenic Monoamines; Dopamine; Environmental Exposure; Formaldehyde; Frontal Lobe; Male; Rats; Serotonin; Synaptosomes
PubMed: 19545605
DOI: 10.1016/j.neulet.2009.06.037 -
Release of immunoreactive alpha-MSH by synaptosome-enriched fractions of homogenates of hypothalami.Brain Research Oct 1979Immunoreactive alpha-melanocyte-stimulating hormone (alpha-MSH) was found to be concentrated in a synaptosome-enriched fraction prepared by differential centrifugation...
Immunoreactive alpha-melanocyte-stimulating hormone (alpha-MSH) was found to be concentrated in a synaptosome-enriched fraction prepared by differential centrifugation of rat hypothalamic homogenates. The release of the hormone from this preparation was investigated. After incubation, the synaptosomes were isolated by ultrafiltration and alpha-MSH in the ultrafiltrate was determined by radioimmunoassay. Particle-bound alpha-MSH, recovered by extraction with acid ethanol, and alpha-MSH released from the synaptosome preparation, were immunologically similar to synthetic alpha-MSH and had an accompanying melanotropic activity. Less than 10% of the particle-bound alpha-MSH was released during incubation in 0.32 M sucrose. However, in the presence of 2 mM Ca2+, alpha-MSH release increased with increasing concentrations (30-150 mM) of K+. The stimulatory effect of 60 mM K+ was complete within 2 min and was potentiated by increasing Ca2+ concentrations over the range of 0 to 2 mM. K+-induced release of alpha-MSH was independent of temperature from 1 to 30 degrees C, and neither glucose (10 mM) nor dopamine (10(-10)-10(-2) M) had any effect on the release of the peptide. It is concluded that a synaptosome-enriched fraction from the hypothalamus contains a releasable pool of immunoreactive alpha-MSH that is mobilized by depolarizing concentrations of K+ in a Ca2+-dependent manner.
Topics: Animals; Calcium; Culture Techniques; Dopamine; Glucose; Hypothalamus; Male; Melanocyte-Stimulating Hormones; Neurosecretion; Potassium; Radioimmunoassay; Rats; Synaptosomes; Temperature
PubMed: 487155
DOI: 10.1016/0006-8993(79)91004-7 -
Brain Research Jan 1976A flotation method for preparing synaptosomes, previously developed for work with squid nervous tissue, has now been successfully applied to the ventral nerve cord of...
A flotation method for preparing synaptosomes, previously developed for work with squid nervous tissue, has now been successfully applied to the ventral nerve cord of lobster. Perhaps due to the greater content of connective tissue, homogenization of the lobster nerve cord was more difficult than with squid optic lobes and the yield of synaptosomes was lower. The synaptosomes fraction showed a 3.8-fold enrichment of bound acetylcholine relative to the homogenate and was almost 10 times richer in acetylcholine than a guinea pig cerebral cortical synaptosome fraction. The lobster synaptosomes accumulated choline rapidly when incubated at room temperature in sea water, and showed a high degree of occlusion of lactate dehydrogenase, thus confirming that they are sealed structures. The lobster can thus be added to the wide range of species from whose nervous systems synaptosomes can be isolated, and merits further study as a possibly rich source of cholinergic synaptosomes.
Topics: Acetylcholine; Animals; Central Nervous System; Choline; Fumarate Hydratase; Histological Techniques; L-Lactate Dehydrogenase; Nephropidae; Subcellular Fractions; Synaptosomes
PubMed: 1104081
DOI: 10.1016/0006-8993(76)90991-4 -
Zeitschrift Fur Naturforschung. Section... 1985Incubation of synaptosomal plasma membranes (SPM) with liposomes of phosphatidylserine (PS), phosphatidylinositol (PIN) or phosphatidylglycerol (PGL), led to an increase...
Incubation of synaptosomal plasma membranes (SPM) with liposomes of phosphatidylserine (PS), phosphatidylinositol (PIN) or phosphatidylglycerol (PGL), led to an increase of acetylcholinesterase (AchE) activity at concentrations of 0.1-1 mumol phospholipids per mg SPM protein. The use of higher concentrations (1-7 mumol/mg protein), however, led to a progressive inhibition of the activity with respect to the maximal percentage of enzyme stimulation. To explain the enzyme stimulation by the acidic phospholipids, AchE was solubilized with the detergent Lubrol-PX and showed no change in the enzyme activity at any PS, PIN or PGL concentration used, indicating that these compounds do not act on the protein molecule directly. Arrhenius plots of AchE activities in untreated SPM (control), exhibited a break point at 23 degrees C, which was decreased to 16-17 degrees C in PS-treated SPM. Moreover, the Arrhenius activation energy (Ea) value in PS-treated SPM was increased related to the Ea below the break point in the control. These results indicate that acidic phospholipids do not act on AchE directly, but indirectly, affecting the membrane fluidity probably. Such modifications of interactions between lipid and AchE may control physiological processes in the central nervous system.
Topics: Acetylcholinesterase; Animals; Brain; Cell Membrane; Dogs; In Vitro Techniques; Phosphatidylglycerols; Phosphatidylinositols; Phosphatidylserines; Phospholipids; Synaptosomes
PubMed: 3993183
DOI: 10.1515/znc-1985-1-219