Mineral trioxide aggregate suppresses pro-inflammatory cytokine expression via the calcineurin/nuclear factor of activated T cells/early growth response 2 pathway in lipopolysaccharide-stimulated macrophages

AIM

To elucidate mechanisms by which mineral trioxide aggregate (MTA) suppresses pro-inflammatory cytokine mRNA expression in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages.

METHODOLOGY

Mineral trioxide aggregate extracts were prepared by immersing set ProRoot MTA in culture medium. RAW264.7 cells were cultured in the presence of LPS and MTA extracts. mRNA expression levels of interleukin (IL)-1α, IL-6, early growth response 2 (Egr2), suppressor of cytokine signalling 3 (Socs3) and IL-10 were quantified with reverse transcription-quantitative polymerase chain reaction. Phosphorylation of nuclear factor-kappa B (NF-κB) p65 in RAW264.7 cells was analysed by Western blotting. Intracellular calcium imaging was performed with Fluo-4 AM. The activity of nuclear factor of activated T cells (NFAT) was determined by luciferase assays. Enforced expression and silencing of Egr2 in RAW264.7 cells were carried out using an expression vector and specific RNAi, respectively. In vivo kinetics of Egr2⁺ cells in MTA-treated rat molar pulp tissues were examined using immunohistochemistry. Data were analysed by one-way analysis of variance, followed by the Tukey-Kramer test (P < 0.05).

RESULTS

Exposure to MTA extracts resulted in reduced mRNA expression levels of IL-1α and IL-6, as well as reduced expression of phosphorylated NF-κB, in LPS-stimulated RAW264.7 cells. Exposure to MTA extracts induced Ca²⁺ influx, which was blocked by NPS2143, an antagonist of calcium-sensing receptor (CaSR); Ca²⁺ influx then triggered activation of calcineurin/NFAT signalling and enhanced mRNA expression of Egr2. Enforced expression of Egr2 in RAW264.7 cells promoted the expression of both IL-10 and Socs3. In vivo application of MTA onto rat molar pulp tissue resulted in the appearance of Egr2-expressing cells that coexpressed CD163, a typical M2 macrophage marker.

CONCLUSIONS

Mineral trioxide aggregate extracts induced downregulation of IL-1α and IL-6 in LPS-stimulated RAW264.7 cells via CaSR-induced activation of calcineurin/NFAT/Egr2 signalling and subsequent upregulation of IL-10 and Socs3.

Fungal Planet description sheets: 868-950

Novel species of fungi described in this study include those from various countries as follows: Australia, Chaetomella pseudocircinoseta and Coniella pseudodiospyri on Eucalyptus microcorys leaves, Cladophialophora eucalypti, Teratosphaeria dunnii and Vermiculariopsiella dunnii on Eucalyptus dunnii leaves, Cylindrium grande and Hypsotheca eucalyptorum on Eucalyptus grandis leaves, Elsinoe salignae on Eucalyptus saligna leaves, Marasmius lebeliae on litter of regenerating subtropical rainforest, Phialoseptomonium eucalypti (incl. Phialoseptomonium gen. nov.) on Eucalyptus grandis × camaldulensis leaves, Phlogicylindrium pawpawense on Eucalyptus tereticornis leaves, Phyllosticta longicauda as an endophyte from healthy Eustrephus latifolius leaves, Pseudosydowia eucalyptorum on Eucalyptus sp. leaves, Saitozyma wallum on Banksia aemula leaves, Teratosphaeria henryi on Corymbia henryi leaves. Brazil, Aspergillus bezerrae, Backusella azygospora, Mariannaea terricola and Talaromyces pernambucoensis from soil, Calonectria matogrossensis on Eucalyptus urophylla leaves, Calvatia brasiliensis on soil, Carcinomyces nordestinensis on Bromelia antiacantha leaves, Dendryphiella stromaticola on small branches of an unidentified plant, Nigrospora brasiliensis on Nopalea cochenillifera leaves, Penicillium alagoense as a leaf endophyte on a Miconia sp., Podosordaria nigrobrunnea on dung, Spegazzinia bromeliacearum as a leaf endophyte on Tilandsia catimbauensis, Xylobolus brasiliensis on decaying wood. Bulgaria, Kazachstania molopis from the gut of the beetle Molops piceus. Croatia, Mollisia endocrystallina from a fallen decorticated Picea abies tree trunk. Ecuador, Hygrocybe rodomaculata on soil. Hungary, Alfoldia vorosii (incl. Alfoldia gen. nov.) from Juniperus communis roots, Kiskunsagia ubrizsyi (incl. Kiskunsagia gen. nov.) from Fumana procumbens roots. India, Aureobasidium tremulum as laboratory contaminant, Leucosporidium himalayensis and Naganishia indica from windblown dust on glaciers. Italy, Neodevriesia cycadicola on Cycas sp. leaves, Pseudocercospora pseudomyrticola on Myrtus communis leaves, Ramularia pistaciae on Pistacia lentiscus leaves, Neognomoniopsis quercina (incl. Neognomoniopsis gen. nov.) on Quercus ilex leaves. Japan, Diaporthe fructicola on Passiflora edulis × P. edulis f. flavicarpa fruit, Entoloma nipponicum on leaf litter in a mixed Cryptomeria japonica and Acer spp. forest. Macedonia, Astraeus macedonicus on soil. Malaysia, Fusicladium eucalyptigenum on Eucalyptus sp. twigs, Neoacrodontiella eucalypti (incl. Neoacrodontiella gen. nov.) on Eucalyptus urophylla leaves. Mozambique, Meliola gorongosensis on dead Philenoptera violacea leaflets. Nepal, Coniochaeta dendrobiicola from Dendriobium lognicornu roots. New Zealand, Neodevriesia sexualis and Thozetella neonivea on Archontophoenix cunninghamiana leaves. Norway, Calophoma sandfjordenica from a piece of board on a rocky shoreline, Clavaria parvispora on soil, Didymella finnmarkica from a piece of Pinus sylvestris driftwood. Poland, Sugiyamaella trypani from soil. Portugal, Colletotrichum feijoicola from Acca sellowiana. Russia, Crepidotus tobolensis on Populus tremula debris, Entoloma ekaterinae, Entoloma erhardii and Suillus gastroflavus on soil, Nakazawaea ambrosiae from the galleries of Ips typographus under the bark of Picea abies. Slovenia, Pluteus ludwigii on twigs of broadleaved trees. South Africa, Anungitiomyces stellenboschiensis (incl. Anungitiomyces gen. nov.) and Niesslia stellenboschiana on Eucalyptus sp. leaves, Beltraniella pseudoportoricensis on Podocarpus falcatus leaf litter, Corynespora encephalarti on Encephalartos sp. leaves, Cytospora pavettae on Pavetta revoluta leaves, Helminthosporium erythrinicola on Erythrina humeana leaves, Helminthosporium syzygii on a Syzygium sp. bark canker, Libertasomyces aloeticus on Aloe sp. leaves, Penicillium lunae from Musa sp. fruit, Phyllosticta lauridiae on Lauridia tetragona leaves, Pseudotruncatella bolusanthi (incl. Pseudotruncatellaceae fam. nov.) and Dactylella bolusanthi on Bolusanthus speciosus leaves. Spain, Apenidiella foetida on submerged plant debris, Inocybe grammatoides on Quercus ilex subsp. ilex forest humus, Ossicaulis salomii on soil, Phialemonium guarroi from soil. Thailand, Pantospora chromolaenae on Chromolaena odorata leaves. Ukraine, Cadophora helianthi from Helianthus annuus stems. USA, Boletus pseudopinophilus on soil under slash pine, Botryotrichum foricae, Penicillium americanum and Penicillium minnesotense from air. Vietnam, Lycoperdon vietnamense on soil. Morphological and culture characteristics are supported by DNA barcodes.

Disseminated Metastatic Tissue Calcification After Orthotopic Liver Transplantation: A Case Report

BACKGROUND

Hypercalcemia has been observed in patients after liver transplantation. However, it is rare that the hypercalcemia induced disseminated tissue calcification and heart failure.

CASE REPORT

We report a rare case of heart failure caused by disseminated metastatic tissue calcification that involved extensive progressive myocardial calcification after liver transplantation. A 20-year-old man with end-stage liver disease due to biliary atresia underwent ABO-incompatible living donor liver transplantation. After successful transplantation, he suffered from antibody-mediated rejection. Subsequently, ABO-matched cadaveric liver retransplantation was successfully performed. Hypercalcemia developed gradually following the second transplantation. His serum calcium level increased to 18.3 mg/dL with sudden onset of ventricular tachycardia. Although he was resuscitated with a cardiopulmonary support device, he died of heart and liver failure. Histopathologic examination revealed systemic disseminated metastatic tissue calcification, including massive myocardial calcification.

CONCLUSION

Progressive worsening of hypercalcemia resulted in disseminated metastatic tissue calcification and massive metastatic myocardial calcification, which led to heart failure after liver transplantation. Because hypercalcemia after liver transplantation can cause fatal tissue calcification, early intervention for hypercalcemia should be considered.

Involvement of innate immunity in the pathogenesis of intestinal Behçet's disease

The involvement of excessive T helper 1 (Th1) cell functions in the pathogenesis of Behçet's disease (BD) has been reported. We therefore studied Toll-like receptor (TLR)-expressing cells, which play important roles in innate immunity in patients with BD. Peripheral blood mononuclear cells (PBMC) of BD and healthy controls, and tissue specimens of intestinal BD and Crohn's disease (CD) were analysed for messenger RNA (mRNA) and protein expressions by reverse transcription-polymerase chain reaction and immunostaining respectively. PBMC of BD expressed TLR-2 and TLR-4 mRNA almost comparable with healthy controls. Intestinal lesions of BD expressed TLR-2 and TLR-4 mRNA consistently. In contrast, TLR-4 mRNA was expressed preferentially and TLR-2 mRNA was expressed less frequently in CD lesions. In intestinal samples of BD, TLR-2 and TLR-4 mRNA were detected in ileocaecal ulcer lesions, but not in unaffected sites of the same sample, indicating the association of the TLR expression with the disease manifestation of intestinal BD. TLR-2-expressing cells which were simultaneously cluster of distribution (CD)68-positive produced interleukin (IL)-12 in the lesions, indicating the participation of TLR-2-expressing cells in the Th1 skewed responses in vivo. As a possible ligand of TLR-2, in BD self-heat shock protein 60 was expressed in peripheral blood lymphocytes and intestinal tissues. Collectively, TLR-2-expressing cells as well as TLR-4-expressing cells accumulated in the intestinal lesions of BD. IL-12 produced by TLR-2-expressing cells may contribute to the induction of Th1-dominant immune responses in intestinal BD.

Txk, a member of the non-receptor tyrosine kinase of the Tec family, forms a complex with poly(ADP-ribose) polymerase 1 and elongation factor 1alpha and regulates interferon-gamma gene transcription in Th1 cells

We have found previously that Txk, a member of the Tec family tyrosine kinases, is involved importantly in T helper 1 (Th1) cytokine production. However, how Txk regulates interferon (IFN)-gamma gene transcription in human T lymphocytes was not fully elucidated. In this study, we identified poly(ADP-ribose) polymerase 1 (PARP1) and elongation factor 1alpha (EF-1alpha) as Txk-associated molecules that bound to the Txk responsive element of the IFN-gamma gene promoter. Txk phosphorylated EF-1alpha and PARP1 formed a complex with them, and bound to the IFN-gamma gene promoter in vitro. In particular, the N terminal region containing the DNA binding domain of PARP1 was important for the trimolecular complex formation involving Txk, EF-1alpha and PARP1. Several mutant Txk which lacked kinase activity were unable to form the trimolecular complex. A PARP1 inhibitor, PJ34, suppressed IFN-gamma but not interleukin (IL)-4 production by normal peripheral blood lymphocytes (PBL). Multi-colour confocal analysis revealed that Txk and EF-1alpha located in the cytoplasm in the resting condition. Upon activation, a complex involving Txk, EF-1alpha and PARP1 was formed and was located in the nucleus. Collectively, Txk in combination with EF-1alpha and PARP1 bound to the IFN-gamma gene promoter, and exerted transcriptional activity on the IFN-gamma gene.

Nicotine inhibits the production of proinflammatory mediators in human monocytes by suppression of I-kappaB phosphorylation and nuclear factor-kappaB transcriptional activity through nicotinic acetylcholine receptor alpha7

Macrophages/monocytes and the proinflammatory mediators, such as tumour necrosis factor (TNF)-alpha, prostaglandin E(2) (PGE(2)), macrophage inflammatory protein (MIP)-1alpha and MIP-1alpha, play a critical role in the progression of immunological disorders including rheumatoid arthritis, Behçet's disease and Crohn's disease. In addition, the nicotinic acetylcholine receptor-alpha7 (alpha7nAChR) subunit is an essential regulator of inflammation. In this study, we evaluated the expression of the alpha7nAChR subunit on human peripheral monocytes and the effect of nicotine on the production of these proinflammatory mediators by activated monocytes. Fluorescein isothiocyanate (FITC)-labelled alpha-bungarotoxin demonstrated the cell surface expression of the alpha7nAchR subunit. Pretreatment with low-dose nicotine caused inhibition of TNF-alpha, PGE(2), MIP-1alpha and MIP-1alpha production, and mRNA expression of TNF-alpha, MIP-1alpha and MIP-1alpha and COX-2 in lipopolysaccharide (LPS)-activated monocytes. These suppressive effects of nicotine were caused at the transcriptional level and were mediated through alpha7nAChR. Nicotine suppressed the phosphorylation of I-kappaB, and then inhibited the transcriptional activity of nuclear factor-kappaB. These immunosuppressive effects of nicotine may contribute to the regulation of some immune diseases.

Excessive expression of Txk, a member of the Tec family of tyrosine kinases, contributes to excessive Th1 cytokine production by T lymphocytes in patients with Behcet's disease

Excessive Th1 cell function is importantly involved in the pathogenesis of Behcet's disease (BD). We previously found that Txk, a member of the Tec family of tyrosine kinases, acts as a Th1 cell specific transcription factor. To investigate immune aberration in the pathogenesis of BD, we studied the expression of Txk and Th1 cytokines in peripheral blood lymphocytes (PBL) and skin lesions in patients with BD. Cytokine production by the lymphocytes was assessed using ELISA. PBL produced excessive Th1 associated cytokines including IFN-gamma and IL-12 spontaneously and in response to exogenous HSP60-derived peptide stimulation, which was shown to induce proliferation of PBL, in patients with BD. Circulating CD4+ T cells expressed excessive Txk protein. A majority of cells infiltrating into skin lesions expressed IFN-gamma in the BD specimens. IL-12 and IL-18 were also expressed in the mononuclear cell aggregates. Lymphocytes accumulating in the skin lesion expressed higher levels of Txk as compared with atopic dermatitis lesions, a typical Th2 disease. IFN-gamma, IL-18 and Il-12 were detected in the BD skin lesions, which may induce preferential development of Th1 cells in patients with BD. The mononuclear cell aggregates contained Txk expressing cells in such skin lesions. Collectively, Txk expressing Th1 cells and the Th1 associated cytokines may play a critical role in the development of skin lesions in BD.

Involvement of Th1 cells and heat shock protein 60 in the pathogenesis of intestinal Behcet's disease

Involvement of excessive Th1 cell functions and heat shock protein expression in the pathogenesis of Behcet's disease (BD) has been reported. In this study we have characterized immune responses in intestinal lesions of BD. Peripheral blood lymphocytes (PBL) of BD and healthy controls (HC) and tissue specimens of intestinal Behcet's disease (intestinal BD), Crohn's disease (CD) and ulcerative colitis (UC) were analysed for mRNA and protein expression by reverse transcriptase-polymerase chain reaction (PCR) and immunohistochemistry, respectively. PBL of BD patients expressed the Th1-related chemokine receptor, CCR5 and CXCR3 preferentially compared with those of healthy controls. Intestinal lesions of BD expressed interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and interleukin (IL)-12 mRNA, indicating Th1 skewed responses in vivo. mRNA of Txk, a Tec family tyrosine kinase specific to Th1 cells, was expressed in the lesions, suggesting its contribution to the Th1-dominant responses. In the intestinal samples, CCR5 was detected in all the cases with BD, whereas Th2-related CCR3 and CCR4 were detected randomly, mainly in the cases with inactive BD and those receiving large amounts of prednisolone, indicating the Th1-dominant immune responses in the intestinal lesions. As the ligands of CCR5, MIP1alpha and MIP1beta were detected, whereas RANTES was not. Heat shock protein (HSP) 60 was expressed in PBL and intestinal tissues of BD. Th1-dominant immune responses and HSP60 expression may induce the inflammatory responses and thus be associated with the pathogenesis of intestinal BD.

Cu, Zn- and Mn-superoxide dismutase levels in brains of patients with schizophrenic psychosis

Impaired oxidative stress defense has been reported in blood of both drug-naïve and antipsychotic-treated patients suffering from schizophrenic psychosis, indicating the involvement of free radical metabolism in the pathogenetic processes of schizophrenia. In this study, the concentrations of two isoenzymes of superoxide dismutase (SOD), Cu, Zn- and MnSOD, were determined with ELISA in various cortical (frontal, parietal, temporal and occipital cortex) and subcortical areas (putamen, caudate nucleus, thalamus, and substantia innominata) of post-mortem brain tissue from patients diagnosed with a schizophrenia spectrum disorder and compared with those of controls. Post-mortem brain tissue from individuals without neuropsychiatric disorders served for control. Cu, Zn- and MnSOD levels were significantly increased in frontal cortex and substantia innominata of the index group, respectively. In all other areas both types of SOD remained virtually unchanged. Detection of SOD changes in the brain supports previous reports of alterations of antioxidant indices in blood cells of patients with schizophrenia and suggests a specific neuroanatomical distribution pattern of oxidative stress processes possibly related to the pathophysiology of schizophrenia.

Recombination activating genes (RAG) induce secondary Ig gene rearrangement in and subsequent apoptosis of human peripheral blood circulating B lymphocytes

Recombination activating gene (RAG) re-expression and secondary Ig gene rearrangement in mature B lymphocytes have been reported. Here, we have studied RAG expression of peripheral blood B lymphocytes in humans. Normal B cells did not express RAG1 and RAG2 spontaneously. More than a half of circulating B cells expressed RAG proteins, when activated with Staphylococcus aureus Cowan I (SAC) + IL-2. DNA binding activity of the RAG complex has been verified by a gel shift assay employing the recombination signal sequence (RSS). Secondary Ig light chain rearrangement in the RAG-expressing B cells was confirmed by linker-mediated (LM)-PCR. Highly purified surface kappa+ B cells activated by SAC + IL-2 became RAG+, and thereafter they started to express lambda chain mRNA. 2 colour immunofluorescence analysis disclosed that a part of the RAG+ cells derived from the purified kappa+ B cells activated by SAC + IL-2 turned to lambda+ phenotype in vitro. Similarly, apoptosis induction was observed in a part of the RAG+ B cells. Our study suggests that a majority of peripheral blood B cells re-expresses RAG and the RAG+ B lymphocytes could be eliminated from the B cell repertoire either by changing Ag receptor specificity due to secondary rearrangement or by apoptosis induction. Thus, RAG expression of mature B cells in peripheral blood would contribute to not only receptor revision for further diversification of B cell repertoire but in some cases (or in some B cell subsets) to prevention or induction of autoAb responses at this differentiation stage in humans.

Free radicals in Parkinson's disease

Although there are a number of hypotheses to explain the pathobiochemistry of Parkinson's disease (PD), the one on oxidative stress (OS) has gained major interest. The evidence for OS participation as a cause of PD can be summarized as follows: 1) OS is involved in physiological aging, 2) there is ample evidence that OS is significantly enhanced in PD compared to age-matched healthy persons, 3) OS is an early feature of PD because OS-dependent aggregation of proteins in the form of advanced glycation end products can be imaged in Lewy bodies at a time in a person's life, when no phenotype of a neurodegenerative disorder is evident, 4) Experimental models of PD show OS and degeneration of dopaminergic neurons. The toxin-induced neurodegeneration can be blocked by antioxidants, and 5) Activated microglia, known to release free radicals and inflammatory cytokines, are present in brains of Parkinsonian patients. In conclusion, a great body of evidence points to the view that OS is a major component underlying the pathobiochemistry of PD. Together a genetic disposition and endogenous/exogenous toxic events of various origins result in a synergistic cascade of toxicity which leads to dysfunction and finally to cell death of dopaminergic neurons. Again, OS plays a significant role in generating cell death signals including apoptosis.

HNF-1 regulates the liver-specific transcription of the chipmunk HP-20 gene

The chipmunk hibernation-specific protein HP-20 is a component of the 140 kDa complex that drastically decreases in the blood during hibernation, and its gene is expressed specifically in the liver. To reveal molecular mechanisms underlying the liver-specific transcription of the HP-20 gene, we isolated chipmunk HP-20 genomic clones. The HP-20 gene spans approximately 6 kb, and consists of three exons. The transcription start site, as determined by 5' RACE-PCR analysis, was found to be 160 bp upstream of the translation initiation codon. Transient transfection studies in HepG2 cells revealed that the 57 bp 5' flanking sequence was sufficient for the liver-specific promoter activity. A database search revealed that this region contains a potential binding site for hepatocyte nuclear factor-1 (HNF-1). In a gel retardation assay, in vitro-synthesized HNF-1 bound to the 5' flanking sequence from -52 to -26. A similar shifted band was also observed with HepG2 nuclear extracts, and this complex was super-shifted by an anti-(HNF-1) Ig. When transfected into COS-7 cells, HNF-1 transactivated transcription from the HP-20 gene promoter, and this activity was abolished by a mutation of the HNF-1 binding site, indicating that HNF-1 plays an important role in HP-20 gene expression.

Identification and molecular cloning of a novel brain-specific receptor protein that binds to brain injury-derived neurotrophic peptide. Possible role for neuronal survival

Brain injury-derived neurotrophic peptide (BINP) is a synthetic 13-mer peptide that supports neuronal survival and protects hippocampal neurons in primary cultures from cell death caused by glutamate. We have developed a monoclonal antibody named mAb 6A22 against the 40-kDa BINP-binding protein, p40BBP. mAb 6A22 inhibits binding between BINP and rat brain synaptosomes and abolishes the protective effect of BINP. The antigen of mAb 6A22 should be the BINP-binding protein that mediates the neuroprotective action of BINP. Using an expression cloning approach with mAb 6A22, we isolated a cDNA encoding a novel receptor protein that shows binding activity of BINP. COS7 cells transfected with the cloned cDNA show binding of BINP and cell surfaces that are stained by 6A22. The mRNA for p40BBP is specific for the rat brain and is increased after birth. From immunohistochemical studies using mAb 6A22, p40BBP increased after kainic acid treatment in rat hippocampal neurons.

Oral administration of tacrolimus in the presence of jejunostomy after liver transplantation

The feasibility of oral administration of tacrolimus in the presence of an intestinal stoma after liver transplantation (LTx) has not been adequately demonstrated. A 10-month-old girl underwent LTx with biliary reconstruction using a Roux-en Y loop. She developed intestinal perforation and underwent a jejunostomy at 40-50 cm distal to the jejunojejunostomy of the Roux-en Y loop on day 8 post-LTx. Tacrolimus was given twice daily via a nasogastric tube or orally; the initial dose of tacrolimus was 0.10 mg/kg/day. Until the time of intestinal perforation, the trough level of tacrolimus ranged from 13.0 to 19.6 ng/mL. The dose-normalized trough concentration (DNTC) of tacrolimus ranged from 130 to 196 ng.kg.day per mg.mL (control: 80-145 ng.kg.day per mg.mL). For a 2-week period when the patient was septic, the tacrolimus dose was reduced to 0.05 mg/kg/day, with a subsequent trough level of 3.6-5.1 ng/mL (DNTC: 72-102 ng.kg.day per mg.mL). After 3 weeks, the dose was increased to 0.175 mg/kg/day with the disappearance of infection; the trough level ranged from 8.5 to 9.7 ng/mL with a peak level of 26.3 ng/mL (DNTC: 48.5-55.4 ng.kg.day per mg.mL). After the initiation of oral feeding, the dose was slightly increased to 0.20 mg/kg/day with the trough level ranging from 8.1 to 9.8 ng/mL (DNTC: 40.5-49 ng.kg.day per mg.mL). After closure of the jejunostomy, the dose of tacrolimus was reduced to 0.075 mg/kg/day to maintain the same trough level (7.9-9.1 ng/mL) and the DNTC ranged from 105 to 121 ng.kg.day per mg.mL. In conclusion, oral administration of tacrolimus may achieve the therapeutic level, even in the presence of jejunostomy after LTx, although the bioavailability is decreased.

Cloning and characterization of a novel serine/threonine protein kinase gene expressed predominantly in developing brain

We have isolated a rat gene, sbk, that encodes a novel serine/threonine protein kinase possessing a consensus sequence for an SH3-binding domain from developing rat brain. Rat SBK comprises 417 amino-acid residues consisting of a serine/threonine protein kinase consensus sequence followed by a C-terminal proline-rich region. Sequence comparison with other known kinases revealed that sbk belongs to a novel family of serine/threonine protein kinases structurally related to a Xenopus gastrula-specific protein kinase, Pk9.7. An in vitro kinase assay demonstrated that the SBK protein autophosphorylates at serine/threonine residues. Transcripts of sbk were strongly detected in brain, and the distribution shows an association with neurons but not glial cells. A marked increase in sbk transcripts was observed in developing brain in the late embryonic stage when dramatic neuronal proliferation, migration, and maturation occur. Fluorescence in situ hybridization analysis was used to map sbk to mouse chromosome 7F1-F3 and rat chromosome 1q21. These data suggest a role for SBK in signal-transduction pathways related to the control of brain development.

Induction of cysteine string protein after chronic antidepressant treatment in rat frontal cortex

We have previously identified 204 partial cDNA fragments (ADRG1-204) as antidepressant related genes/expressed sequence tags. Then, we developed our original cDNA microarrays, on which the 194 clones out of ADRG1-204 were spotted. With this ADRG microarray, we found that the expression of a spot, ADRG55, which representing cysteine string protein (CSP), was significantly increased in rat brain after chronic treatment with a selective serotonin reuptake inhibitor, sertraline. In the present study, reverse transcription-polymerase chain reaction analysis confirmed the induction of CSP at mRNA levels in rat frontal cortex after chronic treatment with two different classes of antidepressants, imipramine or sertraline. Western blot analysis also revealed that CSP-immunoreactivity was increased after antidepressant treatment. In conclusion, our data suggest that CSP is one of the common functional molecules induced after chronic antidepressant treatment.

Three new chlorinated marine steroids, yonarasterols G, H and I, isolated from the okinawan soft coral, Clavularia viridis

Three new chlorinated marine steroids, yonarasterols G, H and I, were isolated from the Okinawan soft coral, Clavularia viridis. Their structures including the absolute configuration were determined based on the results of spectroscopic analysis and chemical conversion.

Highly elevated ultraviolet-induced mutation frequency in isolated Chinese hamster cell lines defective in nucleotide excision repair and mismatch repair proteins

We have isolated N-methyl-N'-nitro-N-nitrosoguanidine-resistant cell lines from 43-3B Chinese hamster ovary cells, which are deficient in the ERCC1 gene involved in nucleotide excision repair. By Western blotting analysis, we found cell lines that are deficient or decreased in the amount of MSH6, or PMS2, or MSH2 proteins. Cell extracts of these cell lines show reduced efficiency of G:T mismatch repair activity. Compared with 43-3B, these cell lines exhibit highly elevated UV-induced mutation rates, indicating that mammalian mismatch repair can suppress UV-induced mutagenesis and may play a role in the fidelity of DNA replication at the sites of UV damage.

[The comparison of sensitivity between immunostaining and a simplified PCR-cold SSCP method in p53 genomic mutations]

The PCR-SSCP (single strand conformational polymorphism) method has been widely employed to screen mutations in a variety of genes because of its rapidity and simplicity in the operation. Using this method, we have examined mutations of some tumor-related genes including p53 and Ki-ras. In this study, we have evaluated the PCR-Cold (non radioactive) SSCP method for detection of p53 point mutations in comparison with immunohistological detection of p53 and PCR-direct sequencing. The results indicated that the PCR-Cold SSCP method had the same sensitivity with that of PCR-direct sequencing method, and had higher sensitivity than that of immunohistochemical method (IHC).

New marine steroids, yonarasterols, isolated from the okinawan soft coral, Clavularia viridis

Six new marine steroids, yonarasterols A through F, were isolated from the Okinawan soft coral, Clavularia viridis. Their structures were determined based on the results of spectroscopic analysis.

Protective effect of nitric oxide against iron-induced neuronal damage

We investigated the effect of nitric oxide (NO) on iron-induced neuronal damage. Incubation of PC12 cells after the addition of FeCl2 induced rapid increases (within 1 hr) in lipid peroxidation and a concentration (0.1-2 mM)-dependent decrease in cell viability at 48 hr, both of which were blocked by deferoxamine and 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-a]pyrazine-3-o ne hydrochloride (MCLA) (a superoxide scavenger) but not by mannitol (a hydroxyl radical scavenger). Iron-induced cytotoxicity was also antagonized by superoxide dismutase with catalase. On the other hand, the NO donors S-nitroso-N-acetylpenicillamine (SNAP), 3-¿(+/-)-(E)-ethyl-2'-[(E)-hydroxylamino]-5-nitro-3-hexenecarbo moyl¿-pyridine (NOR-4), and 2,2'-(hydroxynitrosohydrazono)bis-ethanamine (NOC-18) decreased cell viability 48 hr after addition without increasing lipid peroxidation. However, when added with 1 mM FeCl2, NO donors including NOC-18, SNAP and NOR-4 (0.1-1 mM) inhibited lipid peroxidation in a concentration-dependent manner and suppressed cell death at lower concentrations. Addition of MCLA and NOC-18 also suppressed decreases in iron-induced [3H]thymidine incorporation. In rat brain homogenate, NOC-18 and SNAP both suppressed iron-induced lipid peroxidation. These findings suggest that NO has a dual effect on neuronal viability and can act as an antioxidant which protects neurons from iron-induced damage.

Identification of a novel splice variant of heat shock cognate protein 70 after chronic antidepressant treatment in rat frontal cortex

In this study, we identified a novel splice variant of 70-kDa heat shock cognate protein (HSC70), while screening differentially expressed molecules in rat brain after chronic antidepressant treatment. This clone, named HSC49, lacked 470 bp of nucleotides of rat HSC70. HSC49 encoded 442 amino acid residues with a calculated molecular mass of 48.6 kDa. DNA sequence analysis revealed that HSC49 lacked the entire Exon 7 and Exon 8 of the HSC70 gene. Chronic treatment with antidepressant, imipramine or sertraline, induced a 38.5 or 22.5% increase in mRNA levels in rat frontal cortex, respectively, when compared to controls. Western blot analysis also revealed that the protein expression of HSC49 was increased after antidepressant treatment. Our data suggest that HSC49 may be one of the common molecules induced after chronic antidepressant treatment.

Dopamine D3 receptor gene polymorphism and alcohol dependence: relation to personality rating

Hereditary dopaminergic mechanisms have been implicated in the aetiology of alcoholism. For this study, the distribution of a dopamine D3 receptor gene polymorphism (Ball) has been investigated in patients suffering from alcohol dependence, and compared with non-dependent controls. The allele A1 occurred significantly more frequently among patients compared to controls. Patients with the genotype A1/A2 showed significantly higher novelty seeking (NS) scores in the tridimensional personality questionnaire (TPQ) than patients with the genotype A1/A1. The distribution of patients with high and low NS scores in heterozygotes (A1/A2) did not follow a random distribution. There were significantly more individuals with higher NS scores, and fewer individuals with lower NS scores than expected. The results of this study support the hypothesis of a genetically determined involvement of the dopaminergic system in alcohol dependence. This is probably related to the modulation of personality traits. The observed effects are relatively small, but statistically significant. Thus, the genetics of the dopaminergic neurotransmitter system alone cannot explain the aetiopathogenesis of alcoholism.

Synthesis and antifungal activity of novel thiazole-containing triazole antifungals. II. Optically active ER-30346 and its derivatives

A series of novel thiazole-containing triazole antifungals was synthesized and evaluated for antifungal activity against a variety of clinically isolated pathogenic fungi in vitro and against systemic candidosis in vivo. These compounds showed potent antifungal activities in vitro and in vivo. In particular, (2R,3R)-3-[4-(4-cyanophenyl)thiazol-2-yl]-2-(2,4- difluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-2-butanol (12g; ER-30346) showed potent and well-balanced in vitro activities and potent in vivo efficacy, and had a good safety profile.

Increase in Bcl-2 level promoted by CD40 ligation correlates with inhibition of B cell apoptosis induced by vacuolar type H(+)-ATPase inhibitor

We have previously demonstrated that cell death of WEHI-231 cells induced by specific inhibitors of vacuolar type H(+)-ATPase (V-ATPase) occurs through apoptosis. CD40 is involved in regulating activation, differentiation, and apoptosis of B cells. Here we show that the CD40 ligation rescues WEHI-231 cells from apoptotic cell death induced by a specific V-ATPase inhibitor, concanamycin A. CD40 signaling with anti-CD40 antibody resulted in the induction of Bcl-2 and Bcl-XL proteins in WEHI-231 cells. Constitutive expression of Bcl-2 but not Bcl-XL inhibited concanamycin A-induced apoptosis. These findings suggest that the expression of Bcl-2 mediated through CD40 signaling rescues the apoptotic cell death induced by blockade of V-ATPase. Interestingly, the acidification of intracellular acidic compartments was completely inhibited when WEHI-231 cells were cultured with concanamycin A, even in the presence of anti-CD40 antibody. In addition, apoptosis in WEHI-231 cells induced by concanamycin A was strongly suppressed when cultured with imidazole, a cell-permeable base, suggesting that apoptosis induced by concanamycin A is preceded by intraacidification.

Relationship of prison life style to blood pressure, serum lipids and obesity in women prisoners in Japan

This prospective study of female prison inmates assessed the effects of prison labour life style on the blood pressure (BP), serum lipids, and body mass index of pre- and postmenopausal female prisoners. This study was carried out in the largest women's prison, located in a town in the North East of Japan. The prison serves a reasonably large community. Three hundred and twelve premenopausal female prisoners and 88 postmenopausal female prisoners in a women's prison participated in this study. Weight and height were measured to calculate the body mass index, and systolic and diastolic blood pressure were measured with a sphygmomanometer. Serum samples were collected for serum lipid estimations. Base-line data of two groups were compared by unpaired t-test, and changes in these data from the initial values were tested by paired t-test. From our limited data, both the pre- and postmenopausal female prisoners showed decreases in systolic and diastolic pressure, total cholesterol, triglycerides, LDL-cholesterol, and body mass index. Both also showed increases in HDL-cholesterol. Given that almost all the women in this prison had the same labour life style, the findings of this study suggest that BP, the serum lipids concentration and obesity can be changed effectively by prison labour life, but are less readily changed in postmenopausal than in premenopausal women.

[Wernicke's encephalopathy developed several years after total gastrectomy. Report of 2 cases]

We present here 2 cases of Wernicke's encephalopathy developed several years after total gastrectomy. Case 1. A 48-year-old male developed impaired recent memory and unsteady gait. He had undergone total gastrectomy for advanced gastric cancer 5 years previously; he had been on tegafur regimen for 4 and a half years. He had had 630 ml of beer every day for 6 months until admission. On admission, there were bilateral abducens palsy, horizontal nystagmus, gait ataxia, and areflexia. Cranial MR imaging was unremarkable. After intravenous infusion of vitamin B1, the patient improved. Case 2. A 56-year-old male developed exertional dyspnea, memory loss, and unsteady gait. He had undergone total gastrectomy for a large submucosal tumor 4 years previously; he had had 300-500 ml of sake almost every day thereafter. Examination revealed bilateral abducens palsy, severe gait ataxia, and areflexia. Chest CT scans demonstrated moderate amount of pericardial effusion. Blood vitamin B1 level was abnormally low. After administration of vitamin B1, he improved. Both patients had had alcoholic drinks; laboratory findings demonstrated no liver dysfunction. Drinking alcohol, even in relatively small quantities, could precipitate the development of Wernicke's encephalopathy in gastrectomized individuals. Our 2 cases stress the importance of supplementary vitamin B1 administration after total gastrectomy.

Tissue-specific regulation of mouse core 2 beta-1,6-N-acetylglucosaminyltransferase

Mouse kidney beta-1,6-GlcNAc-transferase (GNT) is the key enzyme for the synthesis of a glycosphingolipid (Galbeta1-4(Fucalpha1-3)GlcNAcbeta1-6(Galbeta1 -3)GalNAcbeta1-3Galalph a1-4Galbeta1-4Glcbeta1-ceramide) that contains the LeX trisaccharide epitope at its nonreducing terminus. The expression of this glycolipid in the kidney is polymorphic; it is expressed in BALB/c but not DBA/2 mice; and a single autosomal gene (Gsl5) is responsible for this polymorphism. We report here the cDNA sequence that encodes the kidney GNT of BALB/c mice, which possess a wild-type Gsl5 gene. The deduced amino acid sequence exhibits 84% identity to that of human core 2 beta-1,6-GlcNAc-transferase, which suggests that kidney GNT is a mouse homologue of human core 2 beta-1, 6-GlcNAc-transferase. The GNT mRNA is expressed abundantly in the kidney, but was not detected in other BALB/c organs or in the kidneys of DBA/2 mice by Northern blot analysis. In addition, we were able to clone and sequence another homologous cDNA from the submandibular gland. The two sequences differ only in their 5'-untranslated region. The submandibular gland type of cDNA was detected in various organs of DBA/2 mice by reverse transcription-polymerase chain reaction, which indicates that the submandibular gland type is ubiquitous and that its expression is not regulated by the Gsl5 gene. Results obtained using the long accurate polymerase chain reaction method indicate that the GNT gene is approximately 45 kilobases long, and the order of the exons from the 5'-end is exon 1 of the kidney type, exon 1 of the ubiquitous type, exon 2, and exon 3. Exons 2 and 3 are present in both transcripts, and the translated region is in exon 3. These data suggest that the expression of GNT is regulated by an alternative splicing mechanism and also probably by tissue-specific enhancers and that Gsl5 regulates the expression of GNT only in the kidney.

Time course of manganese superoxide dismutase concentrations in serum of alcohol-dependent patients during abstinence

Mean manganese superoxide dismutase (Mn-SOD) concentrations in the serum of patients suffering from alcohol dependence is almost twice as high as in serum of non-dependent controls. In order to investigate the time course of this parameter during abstinence, we determined it at different time points. Patients had mean Mn-SOD serum concentrations (+/-S.D.) of 150.4 +/- 76.3, 121.1 +/- 40.7, 94.6 +/- 37.8 micrograms/ml at 1, 10 and 40 days after abstinence compared to 76.3 +/- 16.9 micrograms/ml as mean Mn-SOD value in the control group. Although the Mn-SOD concentration tended to normalise during abstinence, the differences between index and control group remained significant up to the last measurement at day 40.

Behavioral stimulation without alteration of beta and 5-HT receptors and adenylate cyclase activity in rat brain after chronic sertraline administration

Effects of chronic treatment with selective 5-HT reuptake inhibitors (SSRIs) on the monoaminergic functions have not been much investigated in compared with tricyclic antidepressants. Therefore, we compared the effects of 3-week treatment with sertraline, a potent SSRI, to those of imipramine (10 mg/kg, IP, twice a day), on monoamine receptors and adenylate cyclase (AC) activity in rat brain. Two-week treatment with both sertraline and imipramine reduced immobility in the water wheel test to the comparable extent. Sertraline treatment did not affect Kd and Bmax of [3H]CGP12177 and [3H]ketanserin bindings or cAMP, accumulation by norepinephrine, isoproternol, 5'-guanylylimidodiphosphate [Gpp(NH)p] and forskolin in the cortical membrane compared with vehicle-treated rats. On the other hand, imipramine treatment decreased Bmax of both bindings and norepinephrine- or isoproternol-stimulated cAMP accumulation. Treatment with either antidepressant induced no apparent changes in [3H]8-OH-DPAT [2-(N, N-dipropylamino)-8-hydroxy-1,2,3,4-tetrahydronaphthalene] binding in the hippocampal membrane. These results suggested that chronic treatment of sertraline induced little effect on monoamine receptors and AC activity in the brain and that the alteration of these functions may not be primarily involved in antidepressive effects of antidepressants, at least of SSRIs.

Ciliary neurotrophic factor (CNTF) genotypes: influence on choline acetyltransferase (ChAT) and acetylcholine esterase (AChE) activities and neurotrophin 3 (NT3) concentration in human post mortem brain tissue

Cell culture and animal models suggest a significant influence of ciliary neurotrophic factor (CNTF) on cholinergic neurotransmitter systems. We therefore conducted an explorative pilot study to investigate the influence of a null mutation allele of the CNTF gene on ChAT (choline acetyltransferase) and AChE (acetylcholine esterase) activities in various regions of human post mortem brain tissue. Additionally, we determined NT3 (neurotrophin 3) levels, a factor which exhibits neurotrophic properties at cholinergic neurons, and the concentration of which in these brain regions varies with CNTF genotype. Homozygous carriers of the mutation lack CNTF completely, whereas heterozygotes have a CNTF level which is about half that of non-carriers. There was a trend toward lower ChAT and AChE activity levels in the cingulate cortex in individuals homozygous or heterozygous for the mutation when compared with non-mutant individuals. Additionally, higher NT3 concentrations were found in this region, as well as in the frontal cortex and caudate nucleus. ChAT and AChE activities in the frontal cortex and caudate nucleus were not significantly linked to CNTF genotype. These results are, however, preliminary and need to be further explored. The individuals investigated were heterogenous with respect to a range of parameters; nevertheless, the hypothesis that genetic variants for neurotrophic factors play a role in diseases of neural development and plasticity deserves further examination.

[Prevalence of hepatitis C virus and human immunodeficiency virus infection among female prison inmates in Japan]

To investigate the prevalence of hepatitis C virus and human immunodeficiency virus infection in female inmates, 504 out of 513 female inmates in a certain female prison in Japan were tested for anti-hepatitis C virus, anti-hepatitis B virus, anti-hepatitis A virus and anti-human immunodeficiency virus makers. They were also interviewed with regard to past history of blood transfusion, tattooing, acupuncture, intravenous drug abuse, and psychiatric disease. Prevalence of seropositives for anti-hepatitis C virus antibody was found to be significantly higher in prisoners who had a history of intravenous drug abuse (63%) compared to the controls (4.5%). There was no difference between the two groups in prevalence of seropositivity for anti-hepatitis B, anti-hepatitis A and anti-human immunodeficiency virus. Of all inmates who had a history of intravenous drug abuse, anti-hepatitis C positives used drugs longer and in greater quantities than anti-hepatitis C negatives. From these results it is concluded that intravenous drug abuse is a predominant risk factor for hepatitis C virus infection.

The molecular cloning and expression of alpha 2,8-sialyltransferase (GD3 synthase) in a rat brain

We have cloned the cDNA for a GD3 synthase (alpha-2,8-sialyltransferase, [EC 2.4.99.8]) from a rat embryonic brain cDNA library. Mammalian cells transfected with the cloned cDNA expressed GD3 on the cell surface and showed GD3 synthase activity. The deduced protein (342 amino acid residues) was predicted to have a type II membrane topology containing the "sialyl motif" and was found to be 91% similar to its human homologue. Analysis of the acceptor specificity of GD3 synthase protein indicated that this enzyme catalyzed the biosynthesis of GT1a and GQ1b as well as GD3. Northern blot analyses showed that the GD3 synthase gene is preferentially transcribed in the brain and the spleen. The expression of GD3 synthase mRNA was developmentally regulated, with the highest level in the brain during embryonic days 15 to 18. In situ hybridization analyses demonstrated that the GD3 synthase is strongly expressed in the ventricular/subventricular zone of the embryonic rat brain and retina. In the adult rat, GD3 synthase mRNA was detected in the cerebral cortex, hippocampus, thalamus, and cerebellum. These studies show that the spatio- and stage-restricted expression of GD3 in the developing rat brain may be regulated in part by the level of GD3 synthase mRNA.

Intracellular mechanism of ATP-induced depolarizing response in the bullfrog sympathetic ganglion cells

Application of adenosine triphosphate (ATP) induced a depolarizing response in bullfrog sympathetic ganglion cells, which was associated with a decrease in membrane conductance. This depolarizing response was also produced by application of ADP, but not by adenosine, cyclic-AMP or cyclic-GMP. Suramin, an antagonist for the P2-purinoceptor, suppressed the response, while caffeine, an antagonist for the P1-purinoceptor, did not. Application of phospholipase C (PLC) inhibitors such as Li+ and 4-bromophenacyl bromide also suppressed the response. In addition, protein kinase C (PKC) inhibitors such as staurosporine and H-7 had a suppressant effect, while ryanodine, an inhibitor of Ca2 release, did not. These results suggest that ATP and ADP may stimulate P2-purinoceptor coupled with PLC, producing diacylglycerol, which activates PKC, resulting in the closing of K+ channel.

Cloning and expression of cDNA for O-acetylation of GD3 ganglioside

O-acetylated sialic acids of glycoproteins and gangliosides show cell type-specific and developmentally regulated expression in various systems and sometimes reappear as oncofetal antigens. O-acetylation of sialic acids may influence cell-cell interactions mediated by the sialic acid-binding lectins. Here we describe the molecular cloning and sequencing of a gene that produces O-acetyl disialoganglioside (O-acetyl GD3). Expression analysis showed that this gene product participates the O-acetylation of GD3 ganglioside sialic acid. The deduced amino acid sequence of the product was found to be similar to the milk fat globule membrane glycoprotein.

Acceptor substrate specificity of a cloned GD3 synthase that catalyzes the biosynthesis of both GD3 and GD1c/GT1a/GQ1b

To address the role of alpha2,8-sialyltransferase (GD3 synthase) in the biosynthesis of gangliosides, we examined the substrate specificity of the enzyme. In the ganglioside synthesis pathway, it has been generally accepted that sialyltransferase II (SAT II) catalyzes the production of GD3 from GM3, and sialyltransferase V (SAT V) catalyzes the production of GD1c/GT1a/GQ1b from GM1h/GD1a/GT1b. However, acceptor specificity of the clones GD3 synthase that was isolated from human melanoma cells [Nara, K., Watanabe, Y., Maruyama, K., Kasahara, K., Nagai. Y. & Sanai, Y. (1994) Proc. Natl Acad. Sci. USA 91, 7952-7956] has revealed that this enzyme utilized the gangliosides containing the terminal Sia(alpha2-3)Gas structure of the carbohydrate moiety, which includes GM3, GM1b, GD1a and GT1B as exogenous substrates. Kinetic data also showed that the enzyme was able to utilize both GM3 and GM1b/GD1a/GT1b as acceptor substrates. These data indicate that the enzyme catalyzes the formation of not only GD3 but also GD1c, GT1a, and GQ1B in vitro. Furthermore, by transfection of the cloned human alpha2,8-sialyltransferase cDNA, transient and stable expression of GT1a and GQ1b wa also observed in COS-7 cells and Swiss 3T3 cells that originally lacked SAT II and SAT V activities. These observations indicate that the enzyme has both SAT II and SAT V activities in vivo.

Chromosome mapping of the GD3 synthase gene (SIAT8) in human and mouse

GD3 synthase (CMP-NeuAc:NeuAc alpha 2-3Gal beta 1-4Glc beta 1-1'Cer alpha 2,8-sialyltransferase) is a member of the sialyltransferase family, whose members are characterized by having the sialyl motif and a key regulatory enzyme that controls the ganglioside biosynthesis pathway. The chromosomal location of the GD3 synthase gene (SIAT8) was determined in human and mouse using fluorescence in situ hybridization and interspecific backcross analysis, respectively. The human GD3 synthase gene was mapped to p12.1-p11.2 of chromosome 12. The mouse homologue was mapped 2.8 cM distal to D6Mit52 and 4.3 cM proximal to D6Mit25; this region is syntenic to the short arm of human chromosome 12.

Dimethylsulfoxide potentiates the suppressive effects of lidocaine on synaptic transmission in bullfrog sympathetic ganglion

The effects of dimethylsulfoxide used as a solvent on the suppressive effects of lidocaine on synaptic transmission were examined in the bullfrog sympathetic ganglion. Compound action potentials (CAP) in response to orthodromic stimulation of the presynaptic nerve trunk were recorded extracellularly from the bullfrog sympathetic ganglion. Application of lidocaine dissolved in normal Ringer's solution significantly decreased the amplitude of CAP. This suppressive effect of lidocaine was markedly potentiated when lidocaine was dissolved in 0.1% DMSO solution. A similar potentiating effect of DMSO was observed on the suppressive action of lidocaine on acetylcholine (ACh)-induced depolarizing response recorded intracellularly from the sympathetic ganglion cell. On the other hand, 0.1% DMSO solution alone had no effect on synaptic transmission, resting membrane potential, resting membrane resistance or ACh receptor activity. The present findings suggest that DMSO as solvent should be used carefully because of its potentiating effect on drug actions. Since the effect of lidocaine is due to the suppression of nicotinic ACh receptor at the postsynaptic membrane, DMSO may allosterically act on the nicotinic ACh receptor causing an increase in efficacy of lidocaine.

Cloning, characterization, and tissue distribution of porcine SPAI, a protein with a transglutaminase substrate domain and the WAP motif

The primary and gene structures and tissue distribution of porcine SPAI-2, a protein that belongs to the WAP protein superfamily and has a sodium-potassium ATPase inhibitory activity, were determined by molecular cloning and Northern analysis. A full-length cDNA clone was isolated from a porcine duodenum cDNA library. The cDNA insert encoded a polypeptide of 187 amino acids, which is composed of three domains: a hydrophobic presequence of 21 amino acids, a prosegment of 105 amino acids ending with Asp126, and the mature SPAI-2 sequence of 61 amino acids beginning with Pro127. The prosegment contained 16 repeats of a hexapeptide that is highly homologous to the repetitive sequence found in the transglutaminase domain of the human elafin, an elastase-specific inhibitor that also belongs to the WAP superfamily. The repetitive sequence was demonstrated to be a good substrate of transglutaminase using a recombinant preparation produced in Escherichia coli. A porcine genomic library was then screened for the SPAI gene. Characterization and sequencing of positive clones indicated that the gene is similar to the elafin gene, having 3 exons encoding the 5'-untranslated region and signal sequence, proSPAI, and 3'-untranslated region, respectively. Northern blot analysis revealed intestine-specific expression of SPAI mRNA; the message was especially abundant in the small intestine. ProSPAI was also found in the circulation. The similarity of proSPAI to elafin in the domain structure, the acid-labile nature of the cleavage site (Asp126-Pro127), and the fact that the major form of SPAI in the plasma is proSPAI strongly suggest that proSPAI is not the precursor but rather it is the native form of SPAI. Like elafin, therefore, SPAI appears to be a new type of biologically active substance with a transglutaminase substrate domain that acts as an anchoring sequence.

Expression cloning of a CMP-NeuAc:NeuAc alpha 2-3Gal beta 1-4Glc beta 1-1'Cer alpha 2,8-sialyltransferase (GD3 synthase) from human melanoma cells

Using an expression cloning approach, we have isolated a cDNA encoding GD3 synthase (CMP-NeuAc:NeuAc alpha 2-3Gal beta 1-4Glc beta 1-1'Cer alpha 2,8-sialyltransferase, EC 2.4.99.8), which is a key regulatory enzyme determining the prominence of the ganglioside biosynthesis pathway. The cloned cDNA encodes a 341-amino acid protein containing a single transmembrane domain at its N-terminal region, suggesting that the protein has a type II transmembrane topology. The sequence of alpha 2,8-sialyltransferase showed a high level of similarity with other sialyltransferases at two conserved regions typical in the sialyltransferase family. Transfected cells containing the cloned cDNA expressed GD3 ganglioside on the cell surface, which was detectable with specific anti-GD3 antibody by immunofluorescence and immunostaining after separation of isolated glycolipids on thin-layer chromatography. The cDNA hybridized to a single mRNA species of 2.4 kb in melanoma cells. This sialyltransferase is distinctive in catalyzing the formation of the alpha 2-8 linkage of sialic acids.

Up-regulation of elafin/SKALP gene expression in psoriatic epidermis

The expression of mRNA for elafin/SKALP, an inhibitor of leukocyte elastase and proteinase 3, in human normal and psoriatic epidermis was examined by in situ hybridization. In normal epidermis, elafin/SKALP mRNA was detected in the granular layer, but not in the spinous or basal layers. In fully developed psoriatic lesions, elafin/SKALP mRNA was found in the suprabasal layers of the ridges, and in the upper two thirds of the stratum malpighii at the elongated rete ridges. Intense staining was noted near the subcorneal microabscess in psoriasis vulgaris and under the subcorneal pustule in localized pustular psoriasis. In the marginal psoriatic epidermis, elafin/SKALP mRNA was expressed from the middle or upper spinous layer to the subcorneal layer, and the cells expressing elafin/SKALP mRNA increased especially under the parakeratotic corneal layer intermingled with pyknotic nuclei of neutrophils. These findings suggest that the induction of elafin/SKALP gene expression is related closely to the infiltration of neutrophils into the epidermis in psoriasis and plays an important role in protecting the skin components against the tissue damage caused by the infiltrated leukocytes.

Elastase inhibitor elafin is a new type of proteinase inhibitor which has a transglutaminase-mediated anchoring sequence termed "cementoin"

Elafin was shown to be a new type of proteinase inhibitor which has an anchoring sequence. Human elafin, a potent inhibitor specific for elastase and proteinase 3, has a unique repeating sequence in its prosegment that is rich in Gln and Lys residues. The prosegment, termed "cementoin," exhibits high homology with the repetitive element of seminal vesicle clotting protein, which is known as a good substrate for prostate transglutaminase. The cross-linking of cementoin by tissue transglutaminase showed that the cementoin moiety is indeed a preferable substrate for transglutaminase. In addition, transglutaminase-mediated cross-linking between cementoin and laminin was observed in vitro, suggesting that cementoin has the ability to covalently attach to other extracellular matrix proteins. To determine whether or not this type of covalent gluing of elafin through the cementoin moiety occurs in vivo, we determined the molecular size of cementoin-elafin in the trachea mucous epithelium by Western blotting; the rationale of this approach is that (i) the trachea is the richest source of cementoin-elafin, as shown below, and (ii) if cementoin-elafin is covalently associated with other proteins, it should migrate as a higher M(r) species on SDS-polyacrylamide gel electrophoresis; cementoin-elafin immunoreactivity was indeed detected at a position corresponding to 50 kDa, a value much higher than that of its monomeric form. RNase protection analysis and immunohistochemical staining revealed that cementoin-elafin is densely distributed in the skin and trachea, and moderately in the stomach, duodenum and small intestine. These sites of localization are consistent with the locations where elastic fibers are abundant.(ABSTRACT TRUNCATED AT 250 WORDS)

Requirement for transglutaminase in the activation of latent transforming growth factor-beta in bovine endothelial cells

A hitherto unknown function for transglutaminase (TGase; R-glutaminyl-peptide: amine gamma-glutamyltransferase, EC 2.3.2.13) was found in the conversion of latent transforming growth factor-beta (LTGF-beta) to active TGF-beta by bovine aortic endothelial cells (BAECs). The cell-associated, plasmin-mediated activation of LTGF-beta to TGF-beta induced either by treatment of BAECs with retinoids or by cocultures of BAECs and bovine smooth muscle cells (BSMCs) was blocked by seven different inhibitors of TGase as well as a neutralizing antibody to bovine endothelial cell type II TGase. Control experiments indicated that TGase inhibitors and/or a neutralizing antibody to TGase did not interfere with the direct action of TGF-beta, the release of LTGF-beta from cells, or the activation of LTGF-beta by plasmin or by transient acidification. After treatment with retinoids, BAECs expressed increased levels of TGase coordinate with the generation of TGF-beta, whereas BSMCs and bovine embryonic skin fibroblasts, which did not activate LTGF-beta after treatment with retinoids, did not. Furthermore, both TGase inhibitors and a neutralizing antibody to TGase potentiated the effect of retinol in enhancing plasminogen activator (PA) levels in cultures of BAECs by suppressing the TGF-beta-mediated enhancement of PA inhibitor-1 (PAI-1) expression. These results indicate that type II TGase is a component required for cell surface, plasmin-mediated LTGF-beta activation process and that increased expression of TGase accompanies retinoid-induced activation of LTGF-beta.

[Neo-adjuvant chemotherapy with tegafur suppository for rectal cancer--evaluation of the antitumor effects, tissue levels of 5-FU and inhibition of thymidylate synthase. Tochigi Colorectal Cancer Study Group]

We evaluated antitumor effect histologically and assayed the tissue levels of 5-fluorouracil (5-FU) and thymidylate synthase (TS) activity using surgical specimens obtained from the patients with rectal cancer, who were given tegafur suppositories prior to surgery. The antitumor effect was evaluated histologically according to classification of the general rules for the gastric cancer study (Japanese Research Society for Gastric Cancer). In 39 patients, 16 tumor specimens revealed no effect (grade-0), 22 tumors grade-1 effect, and one was not evaluable because of the severe inflammatory changes. In 23 of these patients, resected specimens were available for the assay. 5-FU levels in cancer tissues were significantly higher than those in normal tissues, and TS inhibition rates (TSIR) were almost identical, averaging around 20%, in both cancer and normal tissues. Comparing the 5-FU levels and TS activity according to the histological effects (i.e.: 'grade-0' vs 'grade-1'), the 5-FU levels in the tumors achieved grade-1 were significantly higher than in the tumors showed 'grade 0' (p less than 0.01), and TSIR in the former were relatively greater than in the latter (p = 0.053). It is suggested that both tissue levels of 5-FU and TSIR may be useful parameters to predict the anti-tumor effect against rectal cancer after administration of 5-FU and its derivatives.