L-lactate induced proteomic changes in rat hippocampus
Ontology highlight
ABSTRACT: Rats were anesthetized with sodium pentobarbital (50 mg/kg, i.p.) and placed in a stereotaxic instrument (Kopf instrument). After exposing the skull, bilateral craniotomy (0.5 - 0.8 mm holes, 4 mm posterior to bregma and 2.6 mm lateral from midline) was done. In one group of rats (Lactate group), each hippocampus (3.5 mm ventral from the surface of the skull at the craniotomy site) was infused with 100 nmol of L-lactate dissolved in 1µl of ACSF at a flow rate of 0.1 µl/min (controlled by microinjection pump; World Precision Instruments, USA). In another group of rats (ACSF group), 1 µl of artificial cerebrospinal fluid (ACSF; NaCl 124 mM, KCl 3 mM, CaCl2 2.4 mM, MgSO4 1.3 mM, glucose 10 mM, and HEPES 10 mM, pH = 7.3) was infused per HPC. Needle was kept at injection site for additional 5 minutes for the proper dispersion of solution after L-lactate/ACSF infusion. Then rats were kept into their cages for approximately 60 minutes. After that higher dose of sodium pentobarbital was given, and decapitation was done quickly. Following decapitation, the dura mater was removed carefully, and the brain was flipped out from skull into ice cold PBS using spatula. The right and left hippocampus were isolated on an ice-cold plate using sterile forceps and were stored immediately at -80°C until further use. Later, the right hippocampus was used as sample for mass spectrometry (MS).
Project description:This project compares the outer membrane proteome to the proteome of outer membrane vesicles of the bacterium Shewanella onedensis. S. oneidensis outer membrane was purified via the sarkosyl method described in (Brown, 2010). A 50 mL overnight culture of cells were harvested by centrifugation at 10,000× g for 10 min. cell pellet suspended in 20 mL of 20 mM ice-cold sodium phosphate (pH 7.5) and passed four times through a French Press (12000 lb/in2). The lysate was centrifuged at 5,000× g for 30 min to remove unbroken cells. The remaining supernatant was centrifuged at 45,000 × g for 1 h to pellet membranes. Crude membranes were suspended in 20 mL 0.5% Sarkosyl in 20 mM sodium phosphate and shaken horizontally at 200 rpm for 30 min at room temperature. The crude membrane sample was centrifuged at 45,000 × g for 1 h to pellet the OM. The pellet of OM was washed in ice-cold sodium phosphate and recentrifuged. The cells were pelleted by centrifugation at 5000 x g for 20 min at 4°C, and the supernatant was filtered through 0.45 μm pore size filters to remove remaining bacterial cells. Vesicles were obtained by centrifugation at 38,400 x g for 1 h at 4°C in an Avanti J-20XP centrifuge (Beckman Coulter, Inc). Pelleted vesicles were resuspended in 25 ml of 50 mM HEPES (pH 6.8) and filtered through 0.45 μm pore size filters. Vesicles were again pelleted as described above and finally resuspended in 50 mM HEPES, pH 6.8. Extracellular DNA, flagella, and pili can all be co-purified. Protocol was adapted from (Perez-Cruz, 2013).
Project description:Flag-YBX1 overexpressed T24 cells pellets were resuspended with 2 volume of lysis buffer (150 mM KCl, 10 mM HEPES pH 7.6, 2 mM EDTA, 0.5% NP-40, 0.5 mM DTT, 1:100 protease inhibitor cocktail, 400 U/ml RNase inhibitor), and incubated at 4 °C for 30 min with rotation. Then the lysate was centrifuged at 15 000 g for 20 min. Before incubating the lysate with Flag beads, 100ul were taken as input. The anti-Flag M2 magnetic beads (Sigma, 10 μl per mg lysate) were washed with NT2 buffer (200 mM NaCl, 50 mM HEPES pH 7.6, 2 mM EDTA, 0.05% NP-40, 0.5 mM DTT, 200 U/ml RNase inhibitor) four times. Cell lysate was mixed with M2 beads and incubated at 4 °C for 4 h with rotation. The beads were washed two times with 1 ml ice-cold NT2 buffer. Then the beads were subject to Micrococal nuclease (NEB) digestion (1:1 000 000 dilution) for 8 min at 37 °C. The beads were cooled on ice immediately for 5 min and washed two times with 1 ml ice-cold 1× PNK+EGTA buffer (50 mM Tris-HCl pH 7.5, 20 mM EDTA, 0.05% NP-40, 200 U/ml RNase inhibitor) and two times with 1 ml ice-cold 1× PK buffer (50 mM NaCl, 100 mM Tris-HCl pH 7.5, 10 mM EDTA, 0.2% SDS, 200 U/ml RNase inhibitor). Then the beads were digested with 200 μl pre-heated (20 min at 50 °C) Proteinase K and RNAs were extracted with an equal volume of Acid-Phenol: Chloroform, pH 4.5 (Ambion). The RNAs were subjected to rRNA removal and Bisseq. The libraries were sequenced on the Illumina HiSeq X-Ten platform at Novogene (Tianjin, CA) with paired-end 150 bp read length.The m5C sites were called using meRanCall from meRanTK (FDR < 0.01).
Project description:The APEX2-TLK2 transfected cells were incubated with 500 mM biotin-phenol for 30 minutes in the incubator. Equivoluminal 2 mM media-diluted H2O2 was added to the cells to initiate the labeling reaction for 30 seconds and was removed immediately. The reaction was further quenched by washing three times with ice-cold quenching buffer. Cells were scraped in quenching buffer with protease inhibitors, lysed in RIPA buffer supplemented with 10 mM sodium ascorbate, 1 mM sodium azide, 1 mM Trolox, 1 mM DTT, and protease inhibitors. Samples were briefly sonicated, spun down at 10,000 × g for 10 minutes. The supernatant was incubated with Streptavidin Magnetic Beads at 4°C overnight. The following day, the beads were washed four times with RIPA buffer, two times with 1M KCl solution, two times with 50 mM NH4HCO3 solution, two times with 2 M Urea solution, three times with RIPA buffer, and finally two times with PBS buffer. The beads were then sent to the company (Chi Biomedicine) for digestion and analyzed by Orbitrap Exploris 480 with a FAIMS coupled to an EASY-nanoLC 1200 system under data independent acquisition (DIA) mode with hybrid data strategy.
Project description:T. cruzi epimastigotes in the logarithmic growth phase (3×106 cells mL-1) were incubated for 12h with bortezomib (1.8 µM), GNF6702 (2.9 µM) or compound 1 (24 µM), equivalent to 8× the EC50 values of each compound. Controls were incubated in the presence of diluent (DMSO). Cells were harvested by centrifugation (1912g, 15 min, 4 °C) and washed with ice-cold PBS (1912g, 5 min, 4 °C), and finally, the cell pellets were resuspended in 1.5 mL of ice-cold lysis buffer (1 mM EDTA, 1 mM DTT, 100 μM TLCK, and 1× Roche EDTA-free cOmplete protease inhibitor cocktail in 50 mM potassium phosphate buffer, pH 7.4). Cell suspensions were submitted to 3 freeze–thaw cycles in a dry ice/ethanol bath to biologically inactivate the parasites and then lysed using the One ShotTM Cell disruptor (Constant Systems, UK) at 30 kpsi.
Project description:Time series of eleven breast cancer samples subjected to different cold ischemic stress of up to 3 hr post tumor excision. A different 2x2 factorial within this study evaluated the effect of stabilization method (RNAlater vs snap freezing) and stablization delay (0 and 40 min) at room temperature. Tissue samples were collected at surgery, cut into 1-2 mm pieces and divided into 8 portions. Portions were put in RNAlater or fresh frozen at baseline, 20, 40, 60, 120, and 180 minutes thereafter, or snap frozen in dry ice in a pre-chilled sample vial at baseline and 40 minutes thereafter.
Project description:Bacteria was grown at 30C in 3 different conditions, i.e. SYN (syngas and minimal medium- ATCC no 1789), AC (0.3% acetate in minimal medium- ATCC no 1789) and TSB (tryptic soy broth). After harvesting by centrifugation, O. carboxidovorans pellets (1g) were lysed in 100 mM Tris-Cl pH 8.0, 2% Triton X-100, 2.6 mg/ml sodium azide, 8 mM PMSF by sonication on ice (4 pulses of 15 s duration each). For each condition of growth 4 samples (1g pellets) were separately treated (i.e. lysed and processed further). The supernatants were treated with 50% cold TCA, and the precipitated protein washed with acetone. The pellets were resuspended in solubilization buffer (7M urea, 20 mM tris-Cl, pH 8.0, 5 mM EDTA, 5 mM MgCl2, 4% CHAPS), and protein concentration was determined using the Plus One 2-D Quant Kit (Amersham) following the manufacturers instructions. Protein samples from each treatment were stored at -80 C. One hundred micrograms of each protein sample was resuspended in 0.1 M ammonium bicarbonate, 5% HPLC grade ACN, reduced in 5 mM DTT (65 C, 5 min), alkylated in 10 mM iodoacetamide (30 C, 30 min), and then trypsin digested until there was no visible pellet (1:50 w/w 37 C, 16 h). Peptides were desalted using a peptide microtrap (Michrom BioResources, Auburn, CA) and eluted using a 0.1% TFA, 95% ACN solution. Desalted peptides were dried in a vacuum centrifuge and resuspended in 20 ?l of 0.1% formic acid. Peptides were separated by strong cation exchange (SCX) liquid chromatography (LC) followed by reverse phase (RP) LC coupled directly in line with electrospray ionization (ESI) tandem mass spectrometry (MS/MS). 2DLC ESI MS/MS was done exactly as described (1). All searches were done using TurboSEQUEST (Bioworks Browser 3.2; Thermo Electron). Mass spectra and tandem mass spectra were searched against all annotated proteins from the strain OM5 including all the annotated plasmid-encoded proteins. Cysteine carbamidomethylation and methionine oxidation (single and double) were included in the search strategy. We used the reverse database functionality in Bioworks 3.2 and searched MS2 data against a reversed OM5 database using identical search criteria.
Project description:We investigated the isolated working rat heart as a model to study early transcriptional remodeling induced by cardiac surgery with cardiopulmonary bypass (CPB). Because the mechanisms linking stress hyperglycemia and insulin resistance to increased peri-operative morbidity and mortality in the setting of open-heart surgery are still unclear, we also used this model to determine the transcriptional effects of exogenous glucose supply in absence or in presence of a preexisting state of myocardial insulin resistance. Male Sprague Dawley rats (200-224g) were kept on chow diet for 8 to 10 weeks, or fed a high-sucrose diet to induce myocardial insulin resistance. Following the feeding period, hearts were recovered, arrested in ice-cold Krebs-Henseleit (KH) buffer and subjected to 60 minutes normothermic reperfusion in the working mode with KH buffer supplemented with non-carbohydrate substrates plus glucose (25 mM) or mannitol (25 mM; osmotic control). Compared to non-perfused hearts, perfused hearts from chow-fed rats displayed a more than twofold increased expression for 71 genes (mannitol group) and 103 genes (glucose group) connected to inflammation, cell proliferation, and apoptosis. The same biological pathways were activated in hearts from insulin resistant rats, with 109 genes (mannitol group) and 70 genes (glucose group) up-regulated more than twofold when compared to the non-perfused hearts from high-sucrose diet-fed rats. The changes were highly similar to gene alterations occurring in the right atrium and left ventricle of open heart surgery patients, and included the up-regulation of the three master regulators of metabolic reprogramming MYC, NR4A1 and NR4A2. Targeted pathway analysis revealed an up-regulation of metabolic processes associated with the proliferation and activation of tissue-resident macrophages and fibroblasts. Although the remodeling occurred independently from glucose, glucose further increased the expression of a subset of genes associated with polarization of tissue reparative M2 macrophages. However, glucose failed to enhance the expression of M2-related markers in the isolated heart from rats rendered insulin resistant by high-sucrose feeding. These results expose the cellular components of the heart as a significant source of proinflammatory mediators released in response to stress associated with cardiac surgery with CPB, and suggest a major role for glucose as a signal in the determination of resident cardiac macrophage polarization.
Project description:Cervicovaginal lavage (CVL)supernatants were heat inactivated for 30 minutes at 56°C before further processing. Total protein concentrations were determined using the Pierce Coomassie Plus (Bradford) Protein Assay (Thermo Scientific, Rockford, IL, USA). Sample protein content and volume were normalised with 25mM ammonium bicarbonate (ABC). Soluble proteins were precipitated using an equal volume of ice cold 30% (w/v) TCA in acetone and incubated at -20⁰C for 2 hours. Samples were centrifuged at 12,000g for 10 minutes (4⁰C) to pellet proteins. Pellets were washed three times with ice cold acetone and allowed to air dry. Further sample processing was performed as previously described (Armstrong et al, 2014) with minor modifications. Briefly, protein pellets were resuspended in 25 mM ABC, 0.05%(w/v) rapigest (Waters), reduced and alkylated. Digestion was performed with proteomic-grade trypsin (Sigma-Aldrich, St. Louis, MO, USA) at a protein:trypsin ratio of 50:1. Rapigest was precipitated by addition of trifluoroacetic acid to a final concentration of 0.5% (v/v). Peptide mixtures were analyzed by on-line nanoflow liquid chromatography using the nanoACQUITY-nLC system (Waters MS technologies) coupled to an LTQ-Orbitrap Velos (ThermoFisher Scientific, Bremen, Germany) mass spectrometer equipped with the manufacturer’s nanospray ion source. The gradient of the analytic column (nanoACQUITY UPLCTM BEH130 C18 15cm x 75µm, 1.7µm capillary column) consisted of 3-40% acetonitrile in 0.1% formic acid for 90 min then a ramp of 40-85% acetonitrile in 0.1% formic acid for 5min.
Project description:We performed single nuclei transcriptomics of ventral hippocampus from rats that were food deprived for 24 hours, offered a 30 minute feeding or fast, and then sacrificed 90 minutes later.
Project description:Traumatic brain injury occasionally causes posttraumatic epilepsy. To elucidate the molecular events responsible for posttraumatic epilepsy, we established a rodent model that involved the injection of microliter quantities of FeCl3 solution into the amygdalar nuclear complex. We previously compared hippocampal gene expression profiles in the traumatic epilepsy model and normal rats at 5 days after brain injury (acute phase) and observed the role of inflammation. In this study, we focused on later stages of epileptogenesis. We compared gene expression profiles at 5, 15 (sub-chronic phase), and 30 days (chronic phase) after brain injury to identify temporal changes in molecular networks involved in epileptogenesis. A total of 81 genes was significantly (at least 2-fold) up- or downregulated over the course of disease progression. We found that genes related to lipid metabolism, namely, Apoa1, Gh, Mc4r, Oprk1, and Pdk4, were temporarily upregulated in the sub-chronic phase. Changes in lipid metabolism regulation might be related to seizure propagation during epileptogenesis. This temporal description of hippocampal gene expression profiles throughout epileptogenesis provides clues to potential markers of disease phases and new therapeutic targets. We employed amygdalar FeCl3 injection to induce chronic, recurrent limbic-type partial seizures with spontaneous secondarily generalized seizures in rats . Sixteen male Wistar rats were kept in hanging cages with unlimited access to food and water and 12-h light-dark cycles. Surgical procedures were conducted following anesthesia with intraperitoneal (i.p.) sodium pentobarbital injections (37.5 mg/kg) at 5 weeks of age. Stereotaxic coordinates were determined with the rat brain atlas. The incisor bar was set 3.3 mm below the interaural line. While under anesthesia, a polyethylene tube containing a stylet to serve as an external guide cannula (1.09-mm outer diameter (o.d.), 0.55-mm inner diameter (i.d.), 2.5 cm in length) was stereotaxically implanted and anchored to the skull with miniature screws and dental cement. The cannula was fixed 5.6 mm anterior and 4.8 mm to the right of the lambda and 8.5 mm below the surface of the skull, positioning it at the right amygdaloid body. Randomly selected rats for in vivo microdialysis to estimate redox had guide cannula placed but were prepared without dental cement on the skull where the microdialysis guide cannula was to be placed. Five days later, the stylet was replaced with an internal delivery cannula (0.5 mm o.d., 0.25 mm i.d.). FeCl3 was dissolved in saline solution (100 mM, pH 2.2). FeCl3 solution (1.0 M-NM-<l) was injected through the inner cannula by means of a microinfusion pump (EP-60; Eicom, Tokyo, Japan) set at a rate of 1.0 M-NM-<l/min (Fe group; n = 12). The external guide cannula was used for electroencephalogram (EEG) recording with an electroencephalograph (type 1A63; SAN-EI, Tokyo, Japan). Rats in the control group (n = 4) were each injected with 1.0 M-NM-<l saline (pH 2.2). Both EEG and behavior were observed for at least 6 h after the injection. While we did not measure the rate or frequency of seizures, we did confirm that the animals had recurrent seizures. These observations and the acute recording confirmed the accuracy of the amygdalar injection. No seizure activity was observed in control group rats. Animals in the control group were sacrificed by cervical dislocation 15 days after amygdalar injection. Animals in the Fe group were subdivided into 3 groups and were sacrificed at 5 (acute phase), 15 (sub-chronic phase of injury), and 30 days (chronic phase of injury) after amygdalar injection. The stages of disease development were categorized according to the EEGs of the model rats; within 5 days after amygdalar injection, epileptiform discharges were recorded in the contralateral and ipsilateral amygdalae; by 15 days after injection, interictal spike discharges were more consistently observed in the contralateral uninjected amygdala; at 30 days after injection bilateral interictal spike discharges continued to be observed. After sacrifice, the right hippocampi were immediately removed and placed in ice-cold phosphate-buffered saline and homogenized (Polytron PT 3000; Brinkmann Instruments, Inc., Westbury, NY, USA) for RNA extraction.