ABSTRACT
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
ABSTRACT
Lysine-specific demethylase 1A (LSD1, KDM1A) specifically demethylates di- and monomethylated histones H3K4 and K9, resulting in context-dependent transcriptional repression or activation. We previously identified an irreversible LSD1 inhibitor T-3775440, which exerts antileukemic activities in a subset of acute myeloid leukemia (AML) cell lines by inducing cell transdifferentiation. The NEDD8-activating enzyme inhibitor pevonedistat (MLN4924, TAK-924) is an investigational drug with antiproliferative activities in AML, and is also reported to induce cell differentiation. We therefore tested the combination of these two agents in AML models. The combination treatment resulted in synergistic growth inhibition of AML cells, accompanied by enhanced transdifferentiation of an erythroid leukemia lineage into granulomonocytic-like lineage cells. In addition, pevonedistat-induced rereplication stress during the S phase was greatly augmented by concomitant treatment with T-3775440, as reflected by the increased induction of apoptosis. We further demonstrated that the combination treatment was markedly effective in subcutaneous tumor xenograft models as well as in a disseminated model of AML, leading to tumor eradication or prolonged survival in T-3775440/pevonedistat cotreated mice. Our findings indicate the therapeutic potential of the combination of LSD1 inhibitors and pevonedistat for the treatment of AML.
ABSTRACT
BACKGROUND: Paraneoplastic neurological syndromes (PNS) are rare remote effect of cancer. The antibodies and tumors associated with PNS have been well described, but there are still many clinically suspected cases in which no tumor or antibody can be identified. This is the first report of PNS showing hot cross-bun sign and caused by exceptionally rare underlying malignancy, such as burned-out testicular tumor. CASE PRESENTATION: A 42-year-old man presented subacute progression of hearing loss and cerebellar ataxia. Cerebrospinal fluid showed continuous inflammation and magnetic resonance imaging (MRI) revealed cerebellar atrophy and hot cross-bun sign. Resection of tumors improved both laboratory findings and neurological signs and their pathology was seminoma. CONCLUSION: Seminoma can cause PNS showing 8th cranial nerve palsy, cerebellar, and brainstem atrophy with hot cross-bun sign on MRI study. Extensive screening for onconeural antibodies was negative and thereby suggested that unknown antibodies worked for both antitumor immunity and induction of PNS.
Subject(s)
Paraneoplastic Syndromes, Nervous System/diagnosis , Seminoma/complications , Testicular Neoplasms/complications , Adult , Humans , Male , Paraneoplastic Syndromes, Nervous System/etiologyABSTRACT
Tumor-specific alternative splicing is implicated in the progression of cancer, including clear-cell renal cell carcinoma (ccRCC). Using ccRCC RNA sequencing data from The Cancer Genome Atlas, we found that epithelial splicing regulatory protein 2 (ESRP2), one of the key regulators of alternative splicing in epithelial cells, is expressed in ccRCC. ESRP2 mRNA expression did not correlate with the overall survival rate of ccRCC patients, but the expression of some ESRP-target exons correlated with the good prognosis and with the expression of Arkadia (also known as RNF111) in ccRCC. Arkadia physically interacted with ESRP2, induced polyubiquitination and modulated its splicing function. Arkadia and ESRP2 suppressed ccRCC tumor growth in a coordinated manner. Lower expression of Arkadia correlated with advanced tumor stages and poor outcomes in ccRCC patients. This study thus reveals a novel tumor-suppressive role of the Arkadia-ESRP2 axis in ccRCC.
Subject(s)
Carcinoma, Renal Cell/genetics , Kidney Neoplasms/genetics , Nuclear Proteins/genetics , RNA-Binding Proteins/genetics , Ubiquitin-Protein Ligases/genetics , Alternative Splicing , Blotting, Western , Carcinoma, Renal Cell/metabolism , Carcinoma, Renal Cell/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Disease Progression , Epithelial Cells/metabolism , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic , Gene Ontology , HEK293 Cells , Humans , Kaplan-Meier Estimate , Kidney Neoplasms/metabolism , Kidney Neoplasms/pathology , MCF-7 Cells , Nuclear Proteins/metabolism , Prognosis , Protein Binding , RNA Interference , RNA-Binding Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Ubiquitin-Protein Ligases/metabolism , UbiquitinationABSTRACT
The purpose of this study was to examine the comparative effects of sevoflurane, isoflurane or propofol on cerebral blood flow velocity after tourniquet deflation during orthopaedic surgery. Thirty patients undergoing elective orthopaedic surgery were randomly divided into sevoflurane, isoflurane and propofol groups. Anaesthesia was maintained with sevoflurane, isoflurane or propofol infusion in 33% oxygen and 67% nitrous oxide, in whatever concentrations were necessary to keep bispectral index values between 45 and 50. Ventilatory rate or tidal volume was adjusted to target PaCO2 of 35 mmHg. A 2.0 MHz transcranial Doppler probe was attached to the patient's head at the temporal window and mean blood flow velocity in the middle cerebral artery was continuously measured. The extremity was exsanguinated with an Esmarch bandage and the pneumatic tourniquet was inflated to a pressure of 450 mmHg. Arterial blood pressure, heart rate, velocity in the middle cerebral artery and arterial blood gas analysis were measured every minute for 10 minutes after release of the tourniquet in all three groups. Velocity in the middle cerebral artery in the three groups increased for five minutes after tourniquet deflation. Because of the different cerebrovascular effects of the three agents, the degree of increase in flow velocity in the isoflurane group was greater than in the other two groups, the change in flow velocity in the propofol group being the lowest (at three minutes after deflation 40 +/- 7%, 32 +/- 6% and 28 +/- 10% in the isoflurane, sevoflurane and propofol groups respectively, P < 0.05).
Subject(s)
Anesthetics, Inhalation/pharmacology , Anesthetics, Intravenous/pharmacology , Cerebrovascular Circulation/drug effects , Isoflurane/pharmacology , Methyl Ethers/pharmacology , Middle Cerebral Artery/drug effects , Propofol/pharmacology , Tourniquets , Adult , Aged , Blood Flow Velocity/drug effects , Carbon Dioxide/blood , Humans , Middle Aged , Middle Cerebral Artery/physiology , Orthopedic Procedures , SevofluraneABSTRACT
BACKGROUND: While tumour necrosis factor alpha (TNF-alpha) appears to be associated with the development of non-alcoholic steatohepatitis (NASH), its precise role in the pathogenesis of NASH is not well understood. METHODS: Male mice deficient in both TNF receptors 1 (TNFR1) and 2 (TNFR2) (TNFRDKO mice) and wild-type mice were fed a methionine and choline deficient (MCD) diet or a control diet for eight weeks, maintaining isoenergetic intake. RESULTS: MCD dietary feeding of TNFRDKO mice for eight weeks resulted in attenuated liver steatosis and fibrosis compared with control wild-type mice. In the liver, the number of activated hepatic Kupffer cells recruited was significantly decreased in TNFRDKO mice after MCD dietary feeding. In addition, hepatic induction of TNF-alpha, vascular cell adhesion molecule 1, and intracellular adhesion molecule 1 was significantly suppressed in TNFRDKO mice. While in control animals MCD dietary feeding dramatically increased mRNA expression of tissue inhibitor of metalloproteinase 1 (TIMP-1) in both whole liver and hepatic stellate cells, concomitant with enhanced activation of hepatic stellate cells, both factors were significantly lower in TNFRDKO mice. In primary cultures, TNF-alpha administration enhanced TIMP-1 mRNA expression in activated hepatic stellate cells and suppressed apoptotic induction in activated hepatic stellate cells. Inhibition of TNF induced TIMP-1 upregulation by TIMP-1 specific siRNA reversed the apoptotic suppression seen in hepatic stellate cells. CONCLUSIONS: Enhancement of the TNF-alpha/TNFR mediated signalling pathway via activation of Kupffer cells in an autocrine or paracrine manner may be critically involved in the pathogenesis of liver fibrosis in this NASH animal model.
Subject(s)
Fatty Liver/complications , Kupffer Cells/metabolism , Liver Cirrhosis, Experimental/etiology , Tumor Necrosis Factor-alpha/physiology , Animals , Apoptosis , Cell Adhesion Molecules/biosynthesis , Choline Deficiency/complications , Fatty Liver/metabolism , Fatty Liver/pathology , Gene Expression Regulation , Liver Cirrhosis, Experimental/metabolism , Liver Cirrhosis, Experimental/pathology , Male , Methionine/deficiency , Mice , Mice, Knockout , Mitochondria, Liver/physiology , Mutation , RNA, Messenger/genetics , Receptors, Tumor Necrosis Factor, Type I/deficiency , Receptors, Tumor Necrosis Factor, Type I/genetics , Receptors, Tumor Necrosis Factor, Type I/physiology , Receptors, Tumor Necrosis Factor, Type II/deficiency , Receptors, Tumor Necrosis Factor, Type II/genetics , Receptors, Tumor Necrosis Factor, Type II/physiology , Reverse Transcriptase Polymerase Chain Reaction/methods , Signal Transduction , Tissue Inhibitor of Metalloproteinase-1/biosynthesis , Tissue Inhibitor of Metalloproteinase-1/genetics , Tumor Necrosis Factor-alpha/biosynthesisABSTRACT
The mouse calvarial osteoblast MC3T3-E1 cells released 92 kDa and 68 kDa of gelatinase activities into the conditioned media (CMs) from undifferentiated cells. When differentiation was induced by cultivating cells with ascorbate-2-phosphate (AscP), 68-kDa activity increased significantly in parallel with production of 60-kDa activity. These enzymes required Ca2+ and Zn2+ ions for their proteolytic activities. The 68-kDa activity was immunologically identified as latent matrix metalloproteinase 2 (MMP-2). The 92-kDa activity was deduced to be latent MMP-9 based on its molecular mass. The 60-kDa activity band was found to possess both gelatin and beta-casein hydrolyzing activities, indicating that this activity band might comprise the active form of MMP-2 and latent MMP-13. MC3T3-E1 cells were found to express MMP-2, MMP-13, and membrane type (MT)1-MMP genes by Northern blotting. MMP-2 was expressed constitutively. MMP-13 was up-regulated during the growth with AscP. MT1-MMP expression also was modulated by AscP; at the early stage of differentiation, its messenger RNA (mRNA) level increased and then decreased gradually to the control level. These changes in the profiles of MMPs observed here could be attributed to the maturation of collagenous extracellular matrix (ECM) induced by AscP.
Subject(s)
Ascorbic Acid/pharmacology , Matrix Metalloproteinases/genetics , Matrix Metalloproteinases/metabolism , Osteoblasts/drug effects , Osteoblasts/enzymology , 3T3 Cells , Animals , Cell Differentiation/drug effects , Collagenases/genetics , Collagenases/metabolism , Extracellular Matrix/enzymology , Gene Expression/drug effects , Matrix Metalloproteinase 13 , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , Mice , Osteoblasts/cytology , RNA, Messenger/genetics , RNA, Messenger/metabolismABSTRACT
Titers of anti-double-stranded (ds) DNA antibodies in sera from patients with systemic lupus erythematosus (SLE) using the Crithidia luciliae assay method were compared by conventional titration vs the titration emulation method (ImageTiter) to evaluate whether the latter assay can replace manual titration. Titers by the two methods were identical or within one dilution in 98% (41/42) of samples. A single sample showed a two-dilution difference. Titration emulation showed a tendency to under-estimate the titer of high titer anti-dsDNA samples, although the difference was small. Titration emulation is a suitable alternative to the conventional titration method, offering an accurate and cost-effective approach to quantification of anti-dsDNA antibodies.
Subject(s)
Autoantibodies/analysis , DNA/immunology , Lupus Erythematosus, Systemic/immunology , Animals , Crithidia/immunology , Fluorescent Antibody Technique, Indirect , Humans , Lupus Erythematosus, Systemic/diagnosis , Reagent Kits, Diagnostic , Software , TitrimetryABSTRACT
BACKGROUND: Excessive production of nitric oxide (NO) by the inducible isoform of NO synthase (iNOS) is critically involved in endotoxin (ET)-induced hypotension. Tumor necrosis factor-alpha (TNF-alpha) plays an important role in induction of iNOS. Because activated protein C (APC), a physiological anticoagulant, inhibits TNF-alpha production, it might prevent hypotension by inhibiting excessive production of NO. In this study, we examined this possibility using a rat model of septic shock. METHODS AND RESULTS: Intravenous administration of APC prevented both ET-induced hypotension and the increases in plasma levels of NO(2)(-)/NO(3)(-). The hypotension was also inhibited when APC was administered 30 minutes after ET administration. APC inhibited the increases in lung levels of iNOS activity by inhibiting expression of iNOS mRNA in animals given ET. APC significantly inhibited the increases in lung tissue levels of TNF-alpha and expression of TNF-alpha mRNA in animals given ET. Neither DEGR-F.Xa, a selective inhibitor of thrombin generation, nor DIP-APC, an active site-blocked APC, showed any effect on these ET-induced changes. Both inhibition of TNF-alpha production by leukocytopenia and treatment with anti-rat TNF-alpha antibody produced effects similar to those induced by APC. Aminoguanidine, a selective inhibitor of iNOS, inhibited both the hypotension and the increases in plasma levels of NO(2)(-)/NO(3)(-) in this animal model. CONCLUSIONS: These observations strongly suggest that APC inhibits iNOS induction by decreasing TNF-alpha production, leading to the prevention of ET-induced hypotension. Furthermore, such effects of APC were not dependent on its anticoagulant effects but rather on its serine protease activity.
Subject(s)
Endotoxins/administration & dosage , Hypotension/prevention & control , Nitric Oxide/metabolism , Protein C/pharmacology , Amino Acid Chloromethyl Ketones/chemistry , Animals , Antibodies/pharmacology , Blood Pressure/drug effects , Dansyl Compounds/chemistry , Factor Xa/chemistry , Factor Xa/pharmacology , Hypotension/chemically induced , Hypotension/metabolism , Injections, Intravenous , Isoflurophate/chemistry , Leukopenia/physiopathology , Lung/drug effects , Lung/enzymology , Lung/metabolism , Male , Nitrates/blood , Nitric Oxide Synthase/drug effects , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Nitrites/blood , Protein C/chemistry , RNA, Messenger/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Wistar , Specific Pathogen-Free Organisms , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology , Tumor Necrosis Factor-alpha/metabolismABSTRACT
A carbaryl hydrolase was purified to homogeneity from Arthrobacter sp. strain RC100 by protamine sulfate treatment, ammonium sulfate precipitation, and hydrophobic, anion-exchange, and gel filtration chromatographies. The native enzyme had a molecular mass of 100 kDa and was composed of two identical subunits with molecular masses of 51 kDa. The hydrolase activity was strongly inhibited by DIFP, PMSF, Hg(2+) and paraoxon but not by EDTA. The optimum pH and temperature for the enzyme activity were 9.0 and 50 degrees C, respectively. The enzyme hydrolyzed four N-methylcarbamate insecticides (carbaryl, xylylcarb, metolcarb and XMC), but was not able to hydrolyze fenobucarb, propoxur, and isoprocarb.
Subject(s)
Arthrobacter/enzymology , Carbaryl/metabolism , Carboxylic Ester Hydrolases/isolation & purification , Carboxylic Ester Hydrolases/metabolism , Insecticides/metabolism , Carboxylic Ester Hydrolases/antagonists & inhibitors , Carboxylic Ester Hydrolases/chemistry , Edetic Acid/pharmacology , Enzyme Inhibitors/pharmacology , Hydrogen-Ion Concentration , Kinetics , Mercury/pharmacology , Molecular Weight , Paraoxon/pharmacology , Protease Inhibitors/pharmacology , Protein Subunits , Substrate Specificity , TemperatureABSTRACT
A new type of guided-mode resonant grating filter is described. The filter is independent of polarization state for oblique incidence. The filter has a crossed grating structure, and the plane of incidence on the filter contains the symmetric axis of the grating structure. Theoretical considerations and numerical calculations using two-dimensional rigorous coupled-wave analysis show that a rhombic lattice structure is suitable to such filters. In this configuration an incident light wave is diffracted into the waveguide and is divided into two propagation modes whose directions are symmetric with respect to the plane of incidence. In particular, when the propagation directions of the two modes are perpendicular to each other, the fill factor of grating structure can be approximately 50%. The filter was designed for an incident angle of 45 degrees. Tolerances of setting errors and fabrication errors for this filter were estimated by numerical calculations.
ABSTRACT
We encountered a case of polycystic liver disease for which unroofing and fenestration procedures were performed. The patient was a 55-year-old Japanese female with epigastralgia and abdominal fullness. On computed tomography, millions of low-density areas were seen, particularly in S6, 7, where huge cysts 15 cm in diameter were observed. Magnetic resonance imaging showed a T1 low T2 high-intensity lesion, which was compatible with simple cysts. Unroofing for the cysts in S6, 7 and fenestration of other cysts were performed. Histological examination revealed cuboidal and flat monolayer epithelia with no dysplasia in the wall of the cysts. The postoperative course was uneventful, and the patient's abdominal symptoms remarkably improved. The percentage of the liver volume which was increased in relation to standard liver volume was reduced from 241% (3386 mL: liver parenchyma 750 mL, cysts 2636 mL) to 180% (2525 mL, 1566 mL, 959 mL, respectively) after surgery. The potent mitogen, hepatocyte growth factor, was rapidly increased after the operation and stayed high during the observation period. In this patient, since no liver resection was performed, liver regenerative stimulus was considered to be the loss of space. This phenomenon represents a model of liver regeneration in response to loss of occupied space in an absence of shear stress.
Subject(s)
Cysts/surgery , Liver Diseases/surgery , Liver Regeneration , Cysts/blood , Cysts/diagnostic imaging , Female , Hepatocyte Growth Factor/blood , Humans , Liver Diseases/blood , Liver Diseases/diagnostic imaging , Middle Aged , Tomography, X-Ray ComputedABSTRACT
Two-dimensional periodic structures were fabricated upon a fluorine-doped SiO(2) film in which the fluorine content changed gradually in the direction of film thickness. The films were deposited by plasma-enhanced chemical-vapor deposition. The film was periodically patterned into a 1-mum period and an ~1-mum -groove depth by inductive coupled plasma reactive-ion etching followed by chemical etching in a diluted HF solution. A surface reflectance of 0.7% was attained at 1.85-mum wavelength, a value that is one fifth as large as the 3.5% Fresnel reflection of a SiO(2) substrate with a flat surface.
ABSTRACT
We investigated the ability of honeybees to learn mazes of four types: constant-turn mazes, in which the appropriate turn is always in the same direction in each decision chamber; zig-zag mazes, in which the appropriate turn is alternately left and right in successive decision chambers; irregular mazes, in which there is no readily apparent pattern to the turns; and variable irregular mazes, in which the bees were trained to learn several irregular mazes simultaneously. The bees were able to learn to navigate all four types of maze. Performance was best in the constant-turn mazes, somewhat poorer in the zig-zag mazes, poorer still in the irregular mazes, and poorest in the variable irregular mazes. These results demonstrate that bees do not navigate such mazes simply by memorizing the entire sequence of appropriate turns. Rather, performance in the various configurations depends on the existence of regularity in the structure of the maze and on the ease with which this regularity is recognized and learned.
Subject(s)
Bees , Maze Learning , Orientation , Animals , MemoryABSTRACT
The objective of this study was to determine the role of serum KL-6 levels as a marker for the activity of interstitial pneumonia in patients with connective tissue diseases. The serum concentrations of KL-6, a glycoprotein produced mainly by pulmonary type II epithelial cells, were measured in 21 patients with connective tissue disease. The activity of interstitial pneumonia was compared with the associated serum KL-6 concentrations. Serum KL-6 concentrations in patients with interstitial pneumonia were significantly higher than those in the controls. Among patients with active interstitial pneumonia, serum KL-6 concentrations following the treatment (after improvement) were significantly lower than the pretreatment values. The extent of the pulmonary fibrosis correlated positively with the serum KL-6 concentrations during the inactive phase of the interstitial pneumonia. These results suggest that sequential measurement of serum KL-6 levels is a new and useful means for the evaluation of interstitial pneumonia in patients with connective tissue diseases.
Subject(s)
Antigens/blood , Connective Tissue Diseases/complications , Glycoproteins/blood , Lung Diseases, Interstitial/blood , Lung Diseases, Interstitial/etiology , Peptide Fragments , Procollagen , Antigens, Neoplasm , Biomarkers , Humans , Mucin-1 , MucinsABSTRACT
Cis-retinol/androgen dehydrogenase type 2 (CRAD2) has been shown to catalyze the dehydrogenation of retinols, including 9-cis retinol, and also to exhibit 3alpha- and 17beta- hydroxysteroid dehydrogenase activities. To examine the function of this enzyme and regulation of its gene, the Crad2 gene was cloned from a mouse genomic DNA library and characterized. The complete mouse CRAD2-coding region was found in four exons spanning an approximately 5kb region. The nucleotide sequences of the exons encoding 316 amino acids were identical to those of the previously reported mouse Crad2 cDNA. Primer extension analysis and RNase protection assay were used to map the major transcription initiation sites to the positions lying 87 and 89 base pairs upstream of the ATG translation start codon. The region proximal to the initiation sites exhibited the absence of both TATAA and CAAT boxes. This region had hepatocyte nuclear factor binding sites, consistent with its predominant expression in the liver. Computer analysis of an approximately 7.5kb 5'-flanking region also suggested the presence of binding sites for AP-1, SREBP1, HSF2, c-Rel, c-Myc, CREBP, GATA, Ets, E2F, and Oct-1, suggesting that various factors including retinoic acid, cholesterol, various kinds of stress, the cell cycle, and cyclic AMP may regulate the expression of this gene. Fluorescence in-situ hybridization analysis showed that Crad2 is located at the terminus of mouse chromosome 10, an area that corresponds to band 10D3, suggesting that RDH-related SDRs may be located together in the cluster locus. Northern blot hybridization and RT-PCR analysis demonstrated that CRAD2 was expressed not in early embryonic stages, and not in embryonic stem cells, but instead in the gastrointestinal tract during later embryonic development and adult stage. In conclusion, we have presented the first complete structural analysis, including that of the promoter and chromosomal location, of a member of the retinol/androgen dehydrogenase subfamily of the group of the short-chain dehydrogenase/reductase (SDR) isozymes. Our findings will provide the basis for in-vitro or in-vivo studies concerning the regulation of retinol and androgen metabolism and enable determination of the mechanism of diseases related to retinol, retinal, retinoic acid, and androgen.
Subject(s)
Alcohol Oxidoreductases/genetics , Genes/genetics , Promoter Regions, Genetic , Amino Acid Sequence , Animals , Base Sequence , Cells, Cultured , Chromosome Mapping , DNA/chemistry , DNA/genetics , Embryo, Mammalian/cytology , Embryo, Mammalian/enzymology , Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , In Situ Hybridization, Fluorescence , Isoenzymes/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Inbred Strains , Molecular Sequence Data , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sequence Analysis, DNA , Tissue Distribution , Transcription, GeneticABSTRACT
We examined whether activated protein C (APC) reduces ischemia/reperfusion (I/R)-induced renal injury by inhibiting leukocyte activation. In a rat model, intravenous administration of APC markedly reduced I/R-induced renal dysfunction and histological changes, whereas intravenous administration of dansyl glutamylglycylarginyl chloromethyl ketone-treated factor Xa (DEGR-FXa; active-site-blocked factor Xa), heparin or diisopropyl fluorophosphate-treated APC (DIP-APC; inactive derivative of ARC) had no effect. Furthermore, APC significantly inhibited the I/R-induced decrease in renal tissue blood flow and the increase in the vascular permeability, whereas neither DEGR-FXa, heparin, nor DIP-APC produced such effects. Renal I/R-induced increases in plasma levels of fibrin degradation products were significantly inhibited by APC, DEGR-FXa, and heparin. These observations suggest that APC reduces I/R-induced renal injury independently of its anticoagulant effects but in a manner dependent on its serine protease activity. Renal levels of tumor necrosis factor-alpha (TNF-alpha), rat interleukin-8, and myeloperoxidase were significantly increased after renal I/R. These increases were significantly inhibited by APC but not by DEGR-FXa, heparin, or DIP-APC. Leukocytopenia produced effects similar to those of APC. These findings strongly suggest that APC protects against I/R-induced renal injury not by inhibiting coagulation abnormalities but by inhibiting activation of leukocytes that play an important role in I/R-induced renal injury. Inhibition of leukocyte activation by APC could be explained by the inhibitory activity of TNF-alpha. (Blood. 2000;95:3781-3787)
Subject(s)
Kidney/blood supply , Kidney/pathology , Protein C/pharmacology , Reperfusion Injury/prevention & control , Amino Acid Chloromethyl Ketones/pharmacology , Animals , Antithrombins/pharmacology , Cytokines/metabolism , Factor Xa/pharmacology , Heparin/pharmacology , Humans , Interleukin-8/metabolism , Isoflurophate/pharmacology , Kidney/drug effects , Male , Peroxidase/metabolism , Protein C/therapeutic use , Rats , Rats, Wistar , Regional Blood Flow/drug effects , Tumor Necrosis Factor-alpha/metabolismABSTRACT
Synaptotagmins (Syts) are a large family of membrane proteins consisted of at least 12 isoforms. They are categorized in neuron-specific isoforms (I-V, X, and XI) and ubiquitous isoforms (VI-IX) based on their expression patterns. Syt-I, a neuron-specific and abundant isoform, has been well characterized and postulated to be the exocytotic Ca(2+) sensor. However, the functions of other isoforms remain obscure. Here, we report that ubiquitous isoforms of synaptotagmins, Syt-VII, Syt-VIII, and Syt-IX, interacted with a cytoplasmic RNA-binding protein, SYNCRIP (Synaptotagmin-binding, cytoplasmic RNA-interacting protein), through their C2B domains. SYNCRIP was originally found in the Syt-II C2AB domain bound fraction from the mouse brain lysate. cDNA cloning of SYNCRIP cDNA revealed that the protein was highly homologous to heterogeneous nuclear ribonucleoprotein R (hnRNP R) recently identified. SYNCRIP protein was ubiquitously and constantly expressed in various tissues of mice parallel to hnRNP R. SYNCRIP indeed bound RNA with preference to poly(A) RNA; however, in contrast to the nuclear localization of hnRNP R, SYNCRIP was distributed predominantly in the cytoplasm as judged by both biochemical fractionation and immunohistochemical studies. In vitro binding experiments showed the potential interaction of SYNCRIP with C2B domains of Syts except for those of Syt-V, -VI, and -X. Furthermore, the interaction between SYNCRIP and Syt-VII, -VIII, or -IX was revealed by co-immunoprecipitation experiments using COS cells transiently expressing each Syt isoform. These findings suggested that SYNCRIP was a target of ubiquitous type of Syts and implied the involvement of ubiquitous Syts in the regulation of dynamics of the cytoplasmic mRNA.