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H Sano

Publications and source records attributed to H Sano.

At least 145 records · Page 8Linked to original sources
PubMed2000

Surfactant proteins A and D bind CD14 by different mechanisms.

Surfactant proteins A (SP-A) and D (SP-D) are lung collectins that are constituents of the innate immune system of the lung. Recent evidence (Sano, H., Sohma, H., Muta, T., Nomura, S., Voelker, D. R., and Kuroki, Y. (1999) J. Immunol. 163, 387-395) demonstrates that SP-A modulates lipopolysaccharide (LPS)-induced cellular responses by direct interaction with CD14. In this report we examined the structural elements of the lung collectins involved in CD14 recognition and the consequences for CD14/LPS interaction. Rat SP-A and SP-D bound CD14 in a concentration-dependent manner. Mannose and EDTA inhibited SP-D binding to CD14 but did not decrease SP-A binding. The SP-A binding to CD14 was completely blocked by a monoclonal antibody that binds to the SP-A neck domain but only partially blocked by an antibody that binds to the SP-A lectin domain. SP-A but not SP-D bound to deglycosylated CD14. SP-D decreased CD14 binding to both smooth and rough LPS, whereas SP-A enhanced CD14 binding to rough LPS and inhibited binding to smooth LPS. SP-A also altered the migration profile of LPS on a sucrose density gradient in the presence of CD14. From these results, we conclude that 1) lung collectins bind CD14, 2) the SP-A neck domain and SP-D lectin domain participate in CD14 binding, 3) SP-A recognizes a peptide component and SP-D recognizes a carbohydrate moiety of CD14, and 4) lung collectins alter LPS/CD14 interactions.

Animals↗
PubMed2000

A surrogate method for assessment of beta(2)-integrin-dependent adhesion of human eosinophils to ICAM-1.

We have developed and validated an inexpensive and equivalent method for measuring eosinophil adhesion by beta(2)-integrin to endothelial ICAM-1 using bovine serum albumin (BSA) as a surrogate for the immunoglobulin supergene. The number of adherent eosinophils on BSA or ICAM-1 coated microplates was quantified by residual eosinophil peroxidase activity. Non-stimulated eosinophils did not adhere to either BSA or ICAM-1. However, after IL-5 stimulation, either BSA or ICAM-1 caused comparable and concentration-dependent adhesion of eosinophils. Eosinophil adhesion was rapid and occurred within 15 to 30 min of incubation for either BSA or ICAM-1. Preincubation of cells with CD11b or CD18 antibody specifically decreased adhesion to either BSA or ICAM-1. IL-5, PAF and fMLP all induced adhesion of eosinophils to either BSA or ICAM-1 in a concentration-dependent manner, and the optimal IL-5, fMLP and PAF concentrations for adhesion to BSA were the same as for adhesion to ICAM-1. BSA-binding was specific for beta(2)-integrin; neither alpha-CD49d mAb directed against the alpha(4)-chain or alpha-CD29 directed against the common beta(1)-chain of VLA-4 blocked adhesion to BSA or ICAM-1 controls. The protein tyrosine kinase inhibitor, genistein, the phosphatidylinositol 3-kinase (PI-3 kinase) inhibitor, wortmanin, and mitogen-activated protein kinase kinase (MEK) inhibitor, U0126, all inhibited IL-5-induced eosinophil adhesion to either BSA or ICAM-1 comparably. These results indicate that BSA is a reliable and economical surrogate ligand for ICAM-1 adhesion to beta(2)-integrin-dependent adhesion to ICAM-1. Ligation characteristics of BSA are identical to those for soluble ICAM-1, and the assay is suitable for assessment of signal transduction pathways mediating adhesion.

Androstadienes↗
PubMed2000

An orally active antidiabetic vanadyl complex, bis(1-oxy-2-pyridinethiolato)oxovanadium(IV), with VO(S2O2) coordination mode; in vitro and in vivo evaluations in rats.

According to Pearson's HSAB (hard and soft acids and bases) rule, the vanadyl ion is classified as a hard acid. However, vanadyl-cysteine methyl ester and dithiocarbamate complexes with VO(S2N2) and VO(S4) coordination modes, respectively, that contain bonds with a combination of hard acid (VO2+) and soft base (sulfur) have been found to form stable complexes and exhibit insulin-mimetic activities in in vitro and in vivo evaluations. Based on such observations, a purple bis(1-oxy-2-pyridinethiolato)oxovanadium(IV) (VO(OPT)) complex with VO(S2O2) coordination mode was prepared and found to have a strong insulin-mimetic activity in in vitro evaluation, which followed in vivo effectiveness on intraperitoneal injection and oral administration. Then, we examined the real-time ESR analysis of vanadyl species in the blood of live rats given VO(OPT) by use of the blood circulation monitoring-ESR method. The clearance of vanadyl species from the blood in terms of half-life (t(1/2)) was determined as 15 min in VO(OPT)-treated rats, while t(1/2) of VOSO4-treated rats was 5 min, indicating the long-term acting character of VO(OPT). On the basis of the results, VO(OPT) with VO(S2O2) coordination mode is proposed to be a potent orally active insulin-mimetic complex in treating insulin-dependent diabetes mellitus in experimental animals.

Adipocytes↗
PubMed2000

Preferential inhibition of cyclooxygenase-2 by meloxicam in human rheumatoid synoviocytes.

The aim of this study was to evaluate the anti-inflammatory effect of 4-hydroxy-2-methyl-N-[5-methyl-2-thiazolyl]-2H-1, 2-benzothiazine-3-carboxamide-1,1-dioxide (meloxicam) using cultured rheumatoid synovial fibroblast-like cells (synoviocytes). Synoviocytes were treated with meloxicam in the presence or absence of interleukin-1beta. Meloxicam had no effect on both cyclooxygenase-1 and -2 expression as determined by Western blot analysis, immunohistochemical staining, and reverse transcription polymerase chain reaction (RT-PCR). Even the lower doses of meloxicam inhibited cyclooxygenase-2 activity, but only the higher doses of meloxicam inhibited cyclooxygenase-1 activity as determined by prostaglandin E(2) synthesis assay. So meloxicam had a preferential inhibitory effect of cyclooxygenase-2 relative to cyclooxygenase-1 on cultured rheumatoid synoviocytes without affecting cyclooxygenase expression. On the other hand, indomethacin had no selectivity and dexamethasone inhibited the expression of cyclooxygenase-2. Our data indicate that clinical efficacy and safety of meloxicam for rheumatoid arthritis may result from its preferential inhibition of cyclooxygenase-2 activity relative to cyclooxygenase-1 on rheumatoid synoviocytes.

Anti-Inflammatory Agents↗
PubMed2000

Inhibition of human lung cancer cell growth by the peroxisome proliferator-activated receptor-gamma agonists through induction of apoptosis.

Peroxisome proliferator-activated receptors (PPARs), members of the nuclear hormone receptors superfamily, have an important regulatory role in adipogenesis and inflammation. PPAR-gamma ligands induce terminal differentiation and growth inhibition of human breast cancer cells and prostatic cancer cells. In this study, we demonstrated that PPAR-gamma, but not PPAR-alpha, was expressed in human lung cancer cell lines by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. We also found that the synthetic PPAR-gamma agonist thiazolidinedione compounds (troglitazone) and the endogenous PPAR-gamma ligand, 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)), inhibited the growth of human lung cancer cells through the induction of apoptosis. However, PPAR-alpha agonist (bezafibrate) and other prostanoids (PGE(2), PGF(2alpha)) did not induce apoptosis. These findings suggest that PPAR-gamma may play an important role in the pathogenesis of lung cancer and that PPAR-gamma agonist may be useful therapeutic agents in the treatment of human lung cancer.

Apoptosis↗
PubMed2000

Selective inhibition of cyclooxygenase-2 with antisense oligodeoxynucleotide restricts induction of rat adjuvant-induced arthritis.

The effects of cyclooxygenase (COX)-2 antisense oligodeoxynucleotide (ODN) in induction of adjuvant-induced arthritis were investigated. Female Lewis rats were injected with Mycobacterium butyricum intradermally at the base of tails to induce arthritis. Synthetic 18 mer phosphorothioate ODNs corresponding to the translation initiation site of rat COX-2 mRNA were prepared. The antisense (AS), sense (S), and "scrambled" (Sc) ODNs were intraperitoneally administered. Arthropathy was evaluated with arthritis score, paw edema, and histological examination. Expression of COX-1 and -2 protein and mRNA were examined with immunostaining and reverse-transcription polymerase chain reaction, respectively. COX-2 AS ODN significantly suppressed induction of arthritis in a dose-dependent manner without severe adverse effects, whereas S and Sc ODNs did not show significant inhibitory effects. COX-2 mRNA and protein expression were also suppressed only by COX-2 AS ODN without any alteration of COX-1 expression. These data suggest that selective inhibition of COX-2 with AS ODN may have a therapeutic potency in the treatment of rheumatoid arthritis.

Animals↗
PubMed2000

A new nitroxyl-probe with high retention in the brain and its application for brain imaging.

In order to estimate free radical reactions and image them in the brain of living animals, a nitroxyl spin-probe, carboxy-PROXYL acetoxymethyl ester (CxP-AM) was newly synthesized. CxP-AM was designed to be hydrolyzed by esterase, but not by lipase, so that it would pass through the blood-brain barrier and be retained in the cytosolic phase of parenchymal cells in the brain after intravenous injection. The pharmacokinetics of CxP-AM was compared with those of carboxy-PROXYL (CxP) and its methyl ester (CxP-M). Carboxyl esterase almost completely hydrolyzed CxP-AM within 3 min. After intravenous injection, the brain retained 1.8 times more CxP-AM than CxP-M, and retained it for more than 30 min. Electron spin resonance computed tomographic (ESR-CT) imaging of CxP-AM in the heads of mice produced marked contrast in the encephalon region, while CxP was distributed only in the extracranial region and CxP-M was distributed in both regions, confirming the pharmacokinetics of CxP-AM. The decay rate of CxP-AM determined with time-resolved ESR-CT imaging was different in the two brain regions, suggesting regional differences in the total reducing capability. CxP-AM should become a powerful probe for the investigation and diagnosis of free radical reactions and their imaging in the brain.

Animals↗
PubMed2000

Rice gibberellin-insensitive gene homolog, OsGAI, encodes a nuclear-localized protein capable of gene activation at transcriptional level.

This paper reports isolation and properties of a rice gene, OsGAI, a putative homolog of the GAI of Arabidopsis thaliana. OsGAI encodes a polypeptide of 625 amino acids, which shows 53-55% identity to GAI and RGA from A. thaliana, and 85% identity to wheat rht-D1a and maize d8. Genomic DNA blot analysis indicated the OsGAI to be a single-copy gene in the rice genome. RNA blot hybridization showed that OsGAI transcripts increased within 6h upon GA(3) but not ABA application. This GA-induced increment in OsGAI transcripts did not require de novo protein synthesis. High levels of OsGAI transcripts were detected in nodes, internodes, leaf sheaths and ears of adult plants and leaf sheaths of young seedlings, where GA enhances cell elongation and division. Transiently expressed OsGAI-GFP fusion protein located to the nucleus in onion epidermal cells. Transactivation assays clearly indicated that OsGAI protein is a transcriptional activator or a coactivator.

Amino Acid Sequence↗
PubMed2000

Growth suppression of Escherichia coli by induction of expression of mammalian genes with transmembrane or ATPase domains.

Growth inhibition of Escherichia coli host cells is frequently observed when some mammalian genes are induced to express exogenously. To find common features of these mammalian genes, an assay was designed for the isolation of these genes which show growth-inhibitory effect on E. coli by induction of expression. Of 38,000 clones derived from a mouse brain cDNA library, 64 cDNA clones were systematically selected out by this method, of which 45 clones had putative open reading frames encoding proteins with putative membrane-associated regions or ATP-binding/ATPase activities. These results show that a fraction of membrane-associated proteins or ATP-binding/ATPase genes can be isolated from cDNA libraries by our simple method.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Importance of the carboxy-terminal 25 amino acid residues of lung collectins in interactions with lipids and alveolar type II cells.

Surfactant proteins A and D (SP-A and SP-D) are structurally related members of the collectin family found in the alveolar compartment of the lung. SP-A binds dipalmitoylphosphatidylcholine (DPPC) and galactosylceramide (GalCer), induces liposome aggregation, and regulates the uptake and secretion of surfactant lipids by alveolar type II cells in vitro. SP-D binds phosphatidylinositol (PI) and glucosylceramide. The purpose of this study was to identify a critical stretch of primary sequence in the SP-A region Cys(204)-Phe(228) and the SP-D region Cys(331)-Phe(355) that is involved in protein-specific lipid and type II cell interactions. Chimeras ad1 and ad2 were constructed with rat SP-A/SP-D splice junctions at Cys(218)/Gly(346) and Lys(203)/Cys(331), respectively. Chimera ad1 but not ad2 retained DPPC liposome binding activity. Both chimeras retained significant binding to GalCer liposomes. Chimera ad1 did not bind to PI, whereas chimera ad2 acquired a significant PI binding. Both chimeras failed to induce liposome aggregation and to interact with alveolar type II cells. In addition, monoclonal antibody 1D6 that blocks specific SP-A functions did not recognize either chimera. From these results, we conclude that (1) the SP-A region Leu(219)-Phe(228) is required for liposome aggregation and interaction with alveolar type II cells, (2) the SP-A region Cys(204)-Cys(218) is required for DPPC binding, (3) the SP-D region Cys(331)-Phe(355) is essential for minimal PI binding, and (4) the epitope for mAb 1D6 is located at the region contiguous to the SP-A region Leu(219)-Phe(228).

1,2-Dipalmitoylphosphatidylcholine↗
PubMed2000

A novel snail-related transcription factor Smuc regulates basic helix-loop-helix transcription factor activities via specific E-box motifs.

Snail family proteins are zinc finger transcriptional regulators first identified in Drosophila which play critical roles in cell fate determination. We identified a novel Snail -related gene from murine skeletalmusclecells designated Smuc. Northern blot analysis showed that Smuc was highly expressed in skeletal muscle and thymus. Smuc contains five putative DNA-binding zinc finger domains in its C-terminal half. In electrophoretic mobility shift assays, recombinant zinc finger domains of Smuc specifically bound to CAGGTG and CACCTG E-box motifs (CANNTG). Because basic helix-loop-helix transcription factors (bHLH) bind to the same E-box sequences, we examined whether Smuc competes with the myogenic bHLH factor MyoD for DNA binding. Smuc inhibited the binding of a MyoD-E12 complex to the CACCTG E-box sequence in a dose-dependent manner and suppressed the transcriptional activity of MyoD-E12. When heterologously targeted to the thymidine kinase promoter as fusion proteins with the GAL4 DNA-binding domain, the non-zinc finger domain of Smuc acted as a transcriptional repressor. Furthermore, overexpression of Smuc in myoblasts repressed transactivation of muscle differentiation marker Troponin T. Thus, Smuc might regulate bHLH transcription factors by zinc finger domains competing for E-box binding, and non-zinc finger repressor domains might also confer transcriptional repression to control differentiation processes.

Amino Acid Sequence↗
PubMed2000

Increased interleukin-17 production in patients with systemic sclerosis.

OBJECTIVE: To determine the role of a novel T cell-derived cytokine, interleukin-17 (IL-17), which activates fibroblasts and endothelial cells, in the pathogenesis of systemic sclerosis (SSc). METHODS: We examined IL-17 production by lymphocytes from the peripheral blood (PBL) and from fibrotic lesions of the skin and lungs of SSc patients by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay. We also studied the effect of IL-17 on the proliferation of fibroblasts and on the production of cytokines and the expression of adhesion molecules on endothelial cells in vitro. RESULTS: IL-17 messenger RNA was expressed in unstimulated PBL and lymphocytes from the skin and lungs of SSc patients, but not in similar samples from patients with systemic lupus erythematosus (SLE) or polymyositis/dermatomyositis or from healthy donors. IL-17 levels were also increased in the serum of SSc patients, but not in that of SLE patients or healthy donors. IL-17 overproduction was significantly related to the early stage of SSc, but not to other clinical features of SSc. Moreover, IL-17 enhanced the proliferation of fibroblasts and induced the expression of adhesion molecules and IL-1 production in endothelial cells in vitro. CONCLUSION: IL-17 is overproduced by T cells from the peripheral blood and fibrotic lesions of the skin and lungs in SSc patients. These results suggest that IL-17 overproduction plays an important role in the pathogenesis of SSc, especially in the early stages of the disease, by inducing the proliferation of fibroblasts and the production of IL-1 and the expression of adhesion molecules on endothelial cells.

Adult↗
PubMed2000

Rapid systemic accumulation of transcripts encoding a tobacco WRKY transcription factor upon wounding.

An immediate-early, transiently activated wound-responsive gene was identified in tobacco by fluorescent differential display screening. The full-length cDNA encodes a polypeptide of 356 amino acids with a relative molecular mass of 39,082 Da. The deduced amino acid sequence shows two characteristic features; a leucine-zipper motif found in the more N-terminal region and a WRKY domain containing a zinc-finger motif located in the central region. The gene was designated as wizz (wound-induced leucine zipper zinc finger). Northern analysis showed that upon wounding wizz transcripts were locally and systemically accumulated within 10 min, reached a maximum level by 30 min, and decreased thereafter to the basal level. Analyses of a WIZZ-GFP fusion protein clearly indicated that WIZZ is a nuclear factor. WIZZ specifically binds to sequences containing two TTGAC core motifs that are separated by a spacer of appropriate length. The binding activity was dependent on bivalent cations, most probably zinc. In transient reporter assays, however, WIZZ did not show transactivation activity in tobacco suspension cells, suggesting that it functions together with other components. The results indicate that WIZZ is a new transcription factor which participates in early stages of the wound response.

Amino Acid Sequence↗
PubMed2000

Expression and evolutionary conservation of nanos-related genes in Hydra.

The Drosophila gene nanos encodes two particular zinc finger motifs which are also found in germline-associated factors from nematodes to vertebrates. We cloned two nanos (nos)-related genes, Cnnos1 and Cnnos2 from Hydra magnipapillata. Using whole-mount in situ hybridization, the expression of Cnnos1 and Cnnos2 was examined. Cnnos1 was specifically expressed in multipotent stem cells and germline cells, but not in somatic cells. Cnnos2 was weakly expressed in germline cells and more specifically in the endoderm of the hypostome where it appears to be involved in head morphogenesis. In addition to structural conservation in the zinc finger domain of nanos-related genes, functional conservation of Cnnos1 was also demonstrated by the finding that a Cnnos1 transgene can partially rescue the nosRC phenotype that is defective in the egg production of Drosophila. Thus, the function of nanos-related genes in the germline appears to be well conserved from primitive to highly evolved metazoans.

Amino Acid Sequence↗
PubMed2000

Diverse response of rice and maize genes encoding homologs of WPK4, an SNF1-related protein kinase from wheat, to light, nutrients, low temperature and cytokinins.

The wheat gene WPK4 encodes a 56-kDa protein kinase that belongs to group 3 of the SNF1-related protein kinase family (SnRK3), and is up-regulated by light and cytokinins and down-regulated by sucrose. In order to determine whether or not this particular regulation pattern is general among plant species, we isolated and characterized homologous genes from rice and maize. Two rice genes, OsPK4 and OsPK7, encode proteins comprising 508 and 520 amino acids, and show, respectively, 75% and 76% sequence similarity to WPK4. OsPK4 and OsPK7 proteins produced in Escherichia coli were able to phosphorylate themselves and myelin basic proteins, the reaction requiring magnesium and/or manganese ions. Transcripts of OsPK4 were detected in all tissues tested, and amounts were increased upon illumination, nutrient deprivation and treatment with cytokinins. In contrast, transcripts of OsPK7 were not found in any tissues except in mature leaves at low levels, and did not accumulate under any of the stress conditions examined. A maize gene, ZmPK4, encodes a protein with 518 amino acids that shows 74% similarity to WPK4. Its transcripts were constitutively expressed in all tissues, regardless of light, nutrient and cytokinin status, but were increased upon exposure to low temperature. These results indicate that, despite the sequence similarity between their products, genes for SnRK3 proteins are differentially regulated in response to environmental stimuli.

Amino Acid Sequence↗