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1.
Gut ; 57(11): 1583-91, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18596193

ABSTRACT

OBJECTIVE: No effective drugs have been developed to date to prevent or treat non-alcoholic fatty liver disease (NAFLD), although diet modification and exercise to improve obesity have been attempted. Therefore, development of a novel drug/strategy to treat NAFLD is urgently needed. In the present study, a novel concept is proposed for the treatment of NAFLD. METHODS: Fisher 344 male rats were given a choline-deficient, l-amino acid-defined (CDAA) diet or a high-fat high-calorie (HF/HC) diet with or without the antiplatelet agents, aspirin, ticlopidine or cilostazol for 16 weeks. Liver steatosis, inflammation and fibrosis, and the possible mechanisms involved were investigated. RESULTS: All three antiplatelet drugs, namely aspirin, ticlopidine and cilostazol, significantly attenuated liver steatosis, inflammation and fibrosis in the CDAA diet group. Of the three agents, cilostazol was the most effective, and the drug also suppressed HF/HC diet-induced liver steatosis. Cilostazol appeared to exert its beneficial effect against NAFLD by suppressing mitogen-activated protein kinase activation induced by oxidative stress and platelet-derived growth factor via intercepting signal transduction from Akt to c-Raf. CONCLUSION: Antiplatelet agents, especially cilostazol, offer the promise of becoming key agents for the treatment of NAFLD.


Subject(s)
Fatty Liver/drug therapy , Liver Cirrhosis, Experimental/drug therapy , Platelet Aggregation Inhibitors/therapeutic use , Tetrazoles/therapeutic use , Ticlopidine/therapeutic use , Alanine Transaminase/blood , Animals , Aspirin/therapeutic use , Cholesterol/metabolism , Choline Deficiency/metabolism , Cilostazol , Dietary Fats/metabolism , Drug Evaluation, Preclinical , Fatty Liver/pathology , Humans , Liver Cirrhosis, Experimental/metabolism , Male , Rats , Rats, Inbred F344 , Treatment Outcome
2.
J Biol Chem ; 276(39): 36454-9, 2001 Sep 28.
Article in English | MEDLINE | ID: mdl-11479307

ABSTRACT

The oxidative modification of low density lipoprotein (LDL) has been implicated in the early stage of atherosclerosis through multiple potential pathways, and 12/15-lipoxygenase is suggested to be involved in this oxidation process. We demonstrated previously that the 12/15-lipoxygenase overexpressed in mouse macrophage-like J774A.1 cells was required for the cell-mediated LDL oxidation. However, the mechanism of the oxidation of extracellular LDL by the intracellular 12/15-lipoxygenase has not yet been elucidated. In the present study, we found that not only the LDL receptor but also LDL receptor-related protein (LRP), both of which are cell surface native LDL-binding receptors, were down-regulated by the preincubation of the cells with cholesterol or LDL and up-regulated by lipoprotein-deficient serum. Moreover, 12/15-lipoxygenase-expressing cell-mediated LDL oxidation was decreased by the preincubation of the cells with LDL or cholesterol and increased by the preincubation with lipoprotein-deficient serum. Heparin-binding protein 44, an antagonist of the LDL receptor family, also suppressed the cell-mediated LDL oxidation in a dose-dependent manner. The cell-mediated LDL oxidation was dose-dependently blocked by an anti-LRP antibody but not by an anti-LDL receptor antibody. Furthermore, antisense oligodeoxyribonucleotides against LRP reduced the cell-mediated LDL oxidation under the conditions in which the expression of LRP was decreased. The results taken together indicate that LRP was involved essentially for the cell-mediated LDL oxidation by 12/15-lipoxygenase expressed in J774A.1 cells, suggesting an important pathophysiological role of this receptor-enzyme system as the initial trigger of the progression of atherosclerosis.


Subject(s)
Arachidonate 12-Lipoxygenase/metabolism , Arachidonate 15-Lipoxygenase/metabolism , Macrophages/enzymology , Macrophages/metabolism , Oxygen/metabolism , Receptors, Immunologic/metabolism , Receptors, Immunologic/physiology , Animals , Antibodies/metabolism , Carrier Proteins/metabolism , Cell Line , Cholesterol/metabolism , DNA, Complementary/metabolism , Dose-Response Relationship, Drug , Glycoproteins/metabolism , Heparin/metabolism , Heparin/pharmacology , Humans , LDL-Receptor Related Protein-Associated Protein , Ligands , Lipoproteins, LDL/metabolism , Low Density Lipoprotein Receptor-Related Protein-1 , Mice , Oligonucleotides, Antisense/pharmacology , Protein Binding , Reverse Transcriptase Polymerase Chain Reaction , Swine , Thiobarbituric Acid Reactive Substances , Up-Regulation
3.
J Biol Chem ; 276(36): 33375-83, 2001 Sep 07.
Article in English | MEDLINE | ID: mdl-11443112

ABSTRACT

We previously cloned and characterized thyroid hormone receptor-binding protein (TRBP) as an LXXLL-containing general coactivator that associates with coactivator complexes through its C terminus. To identify protein cofactors for TRBP action, a Sos-Ras yeast two-hybrid cDNA library was screened using TRBP C terminus as bait. A novel coactivator was isolated, coactivator activator (CoAA), that specifically associates with TRBP. Human CoAA is composed of 669 amino acids with a TRBP-interacting domain and two highly conserved RNA recognition motifs (RRM) commonly found in ribonucleoproteins. A splice variant lacking the entire TRBP-interacting domain was also isolated as a coactivator modulator (CoAM), a 156-amino acid protein containing only the RRM region. Human CoAA and CoAM mRNAs are encoded by a single gene located on chromosome 11q13; alternative splicing in exon 2 of CoAA yields CoAM. CoAA interacts with both TRBP and p300 in vitro. In addition, CoAA potently coactivates transcription mediated by multiple hormone-response elements and acts synergistically with TRBP and CREB-binding protein (CBP). Furthermore, CoAA is associated with the DNA-dependent protein kinase-poly(ADP-ribose) polymerase complex. Strikingly, CoAM, which lacks a TRBP-interacting domain, strongly represses both TRBP and CBP action suggesting that CoAM may modulate endogenous CoAA function. These data suggest that CoAA may serve as a mediator of coactivators such as TRBP in gene activation.


Subject(s)
Alternative Splicing , Carrier Proteins/chemistry , Carrier Proteins/genetics , Intracellular Signaling Peptides and Proteins , Amino Acid Sequence , Amino Acids/chemistry , Animals , Base Sequence , Cell Nucleus/metabolism , Cells, Cultured , Chromosomes, Human, Pair 11 , Cloning, Molecular , DNA, Complementary/metabolism , E1A-Associated p300 Protein , Enzyme Activation , Exons , Gene Library , Glutathione Transferase/metabolism , Humans , Introns , Mice , Models, Genetic , Molecular Sequence Data , Nuclear Proteins/metabolism , Plasmids/metabolism , Poly(ADP-ribose) Polymerases/metabolism , Protein Binding , Protein Structure, Tertiary , RNA, Messenger/metabolism , RNA-Binding Proteins/metabolism , Rats , Recombinant Fusion Proteins/metabolism , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Temperature , Tissue Distribution , Trans-Activators/metabolism , Transcription, Genetic , Transfection , Two-Hybrid System Techniques
4.
Gan To Kagaku Ryoho ; 27(12): 1801-4, 2000 Oct.
Article in Japanese | MEDLINE | ID: mdl-11086416

ABSTRACT

The aim of this study was to evaluate the phase I aspects of super high-dose chemotherapy for advanced liver cancer with combined use of PIHP and PBSCT. In 4 patients with HCC and 1 patient with colonic liver metastases, peripheral blood stem cells (PBSC) were mobilized by either i.v. infusion of ETP (180 mg/m2/day for 3 days) or i.a. infusion of doxorubicin (100-120 mg/m2). In 3 (60%) of 5 patients, PBSC for PBSCT were harvested in effective quantities (CFU-GM > or = 2 x 10(5)/kg or CD 34 positive cells > or = 2 x 10(6)/kg). In these 3 patients, a repeated PIHP with either doxorubicin, 5-fluorouracil, or CDDP was carried out 4 weeks after the 1st PIHP. Thereafter, auto-PBSCT was intravenously administered 2 days after PIHP. In the repeated PIHP treatments, although anti-cancer drugs were administered at doses equivalent to or even higher than those administered at the 1st PIHP, bone marrow suppressions were transient and well tolerated. Fatal complications were not observed in any patients. These results indicate that with the combined use of PIHP and PBSCT, high-dose regional chemotherapy of the liver can be safely repeated without systemic toxicities.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Carcinoma, Hepatocellular/therapy , Chemotherapy, Cancer, Regional Perfusion , Hematopoietic Stem Cell Transplantation , Liver Neoplasms/therapy , Adolescent , Adult , Aged , Cisplatin/administration & dosage , Combined Modality Therapy , Doxorubicin/administration & dosage , Female , Fluorouracil/administration & dosage , Humans , Male , Middle Aged , Mitomycin/administration & dosage
5.
FEBS Lett ; 451(1): 81-4, 1999 May 14.
Article in English | MEDLINE | ID: mdl-10356987

ABSTRACT

A novel myosin light chain kinase (MLCK) cDNA was isolated from a HeLa cell cDNA library. The deduced amino acid sequence was identical to that of a zipper-interacting protein kinase (ZIPK) which mediates apoptosis [Kawai et al. (1998) Mol. Cell. Biol. 18, 1642-1651]. Here we found that HeLa ZIPK phosphorylated the regulatory light chain of myosin II (MRLC) at both serine 19 and threonine 18 in a Ca2+/calmodulin independent manner. Phosphorylation of myosin II by HeLa ZIPK resulted in activation of actin-activated MgATPase activity of myosin II. HeLa ZIPK is the first non-muscle MLCK that phosphorylates MRLC at two sites.


Subject(s)
Myosin-Light-Chain Kinase/metabolism , Protein Serine-Threonine Kinases/metabolism , Amino Acid Sequence , Apoptosis Regulatory Proteins , Base Sequence , Calcium-Calmodulin-Dependent Protein Kinases , DNA, Complementary , Death-Associated Protein Kinases , HeLa Cells , Humans , Molecular Sequence Data , Phosphorylation , Protein Serine-Threonine Kinases/genetics
6.
Theriogenology ; 51(4): 709-20, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10728996

ABSTRACT

The present study evaluated the effects of various components in a chemically defined medium on the development of IVM/IVF porcine embryos. The investigated components included energy substrates (lactate, pyruvate or glucose, alone or in various combinations), amino acids (glutamine, glycine or alanine), PVP and HEPES buffer. The effects of each energy substrate were the same as the control. However, a mixture of lactate with either of the other energy substrates increased the development rate. Glutamine tended to decrease rate of the development more than other amino acids, and this inhibition was dose dependent. Both PVP and HEPES buffer did not affect development rate. However, more than 35 mM HEPES buffer induced fragmentation From the above results, a new culture medium was designed (supplemented with 0.276 mM glycine, 0.176 mM alanine, 15 mM HEPES buffer and 1% (wt/vol) PVP in BSA-free Whitten's medium with or without glucose). The new medium resulted in a higher embryo development rate (20.4 and 16.3%) than that obtained with the control medium (10.0%).


Subject(s)
Culture Media, Conditioned , Culture Techniques/veterinary , Fertilization in Vitro/veterinary , Oocytes , Animals , Culture Techniques/methods , Female , Glutamine , HEPES , Lactates , Male , Oocytes/growth & development , Povidone , Swine
7.
Clin Exp Immunol ; 114(1): 1-8, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9764595

ABSTRACT

The B cell line, MRL159.5, was established by somatic hybridization between splenic MRL/MP-lpr/lpr (lpr) mice B cells and 2.52M, a hypoxanthine-aminopterine-thymidine (HAT) medium-sensitive B cell line mutant. It possessed a receptor molecule for mouse erythrocytes treated with bromelain (Br-MRBC) on its surface, likely to be an autoreactive B cell clone specific for Br-MRBC as detected by rosette-forming assay with Br-MRBC. MRL159.5 spontaneously produced IL-6 and secreted IgM, and was induced to augment IgM secretion when treated with Br-MRBC or IL-6. Triggering of CD40 led to an augmentation of IgM secretion as well as IL-6 expression. Blocking the binding of IL-6 to its cellular receptor through the use of inhibitory antibodies inhibited CD40-induced IgM secretion, suggesting a possible autocrine role of IL-6 for CD40-induced differentiation of this B cell hybridoma. Addition of IL-4 or Br-MRBC augmented IL-6 expression as well as IgM secretion by CD40-activated MRL159.5 cells. CD40 also augmented tumour necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression but resulted in decreased IL-10 expression. Furthermore, under conditions where IL-6 expression was augmented, IL-6R alpha (gp80) expression was down-regulated, suggesting a negative feedback mechanism of an IL-6 autocrine loop in this hybridoma. These results demonstrate a role by which T cell-dependent activation through CD40 regulates an IL-6 autocrine loop, controlling differentiation of autoreactive B cells in autoimmune disease.


Subject(s)
B-Lymphocytes/metabolism , Cytokines/genetics , Gene Expression Regulation , Animals , Antibodies, Monoclonal/metabolism , B-Lymphocytes/drug effects , Bromelains/pharmacology , CD40 Antigens/metabolism , Cell Line , Cytokines/metabolism , Granulocyte-Macrophage Colony-Stimulating Factor/biosynthesis , Hybridomas , Immunoglobulin M/biosynthesis , Interleukin-10/biosynthesis , Interleukin-6/biosynthesis , Interleukin-6/genetics , Interleukin-6/metabolism , Mice , Mice, Inbred MRL lpr , Receptors, Antigen, B-Cell/metabolism , Receptors, Interleukin-6/genetics , Transcription, Genetic , Transforming Growth Factor beta/biosynthesis , Tumor Cells, Cultured , Tumor Necrosis Factor-alpha/biosynthesis
8.
Scand J Gastroenterol ; 31(4): 326-33, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8726298

ABSTRACT

BACKGROUND: The effects of teprenone (6,10,14,18-tetramethyl-5,9,13, 17-nonadecatetraen-2-one) on changes in gastric mucosal blood flow, adenosine triphosphate (ATP) content, and incidence of histologic lesions were evaluated in rat gastric mucosa after hemorrhage and retransfusion. METHODS: Teprenone (100 mg/kg) was administered orally once a day for 3 consecutive days. On the 3rd day hemorrhage was induced, withdrawn blood (retransfusion) was returned, and the above variables were determined. RESULTS: Teprenone significantly inhibited the decreases in blood flow and index of mucosal oxygen saturation (ISO2) during hemorrhage in the corpus and antral mucosa. However, no effect of teprenone was observed on systemic blood pressure and ATP levels after hemorrhage and retransfusion. Teprenone significantly (p < 0.05) decreased both the incidence of ischemic lesions and the increase in the severity of lesions after retransfusion in both mucosal regions. CONCLUSION: From these results, it is concluded that the protective effect of teprenone on blood flow was partly responsible for its inhibitory effect on the incidence of lesions in the rat stomach in this hypovolemic shock model, although the former effect might be not a direct effect on systemic vascular tone.


Subject(s)
Anti-Ulcer Agents/pharmacology , Diterpenes/pharmacology , Gastric Mucosa/blood supply , Gastric Mucosa/pathology , Gastrointestinal Hemorrhage/pathology , Adenosine Triphosphate/metabolism , Animals , Blood Transfusion, Autologous , Disease Models, Animal , Energy Metabolism , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Gastrointestinal Hemorrhage/metabolism , Gastrointestinal Hemorrhage/physiopathology , Hemodynamics , Male , Rats , Rats, Wistar , Shock/metabolism , Shock/pathology , Shock/physiopathology
9.
J Comp Pathol ; 113(3): 287-90, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8592054

ABSTRACT

The age-related incidence of thalamic neuronal inclusions in the brains of aged B6C3F1 mice and their histopathological and ultrastructural features were studied. Round to oval or rod-shaped eosinophilic inclusions, which were frequently observed in the neurons of the thalamic area, were stained positively with phosphotungstic acid haematoxylin. The inclusions were detected first at 32 weeks of age and the incidence and severity were higher in older animals, all of the mice being affected after 58 weeks of age. Ultrastructurally, the inclusions appeared as sheaves of parallel osmiophilic filaments in the perikaryon of the neurons in the thalamus. Thus thalamic neuronal inclusions in mice seem to be age-related, but their significance remains unclear.


Subject(s)
Aging/pathology , Inclusion Bodies/ultrastructure , Mice, Inbred Strains/anatomy & histology , Neurons/ultrastructure , Thalamus/ultrastructure , Animals , Female , Hybridization, Genetic , Male , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Microscopy, Electron
10.
J Vet Med Sci ; 57(4): 683-5, 1995 Aug.
Article in English | MEDLINE | ID: mdl-8519898

ABSTRACT

Four of 51 dogs with chronic dermatitis were made to react to crude Japanese cedar (Cryptomeria japonica, CJ) pollen allergen by the intradermal skin test (IDST). These four dogs had specific IgE to CJ as determined by Prausnitz-Küstner test. In the provocation test, nasal discharge increased 5 to 20 min after introduction of the crude CJ pollen allergen into the nasal cavities, in two of three dogs. These results demonstrated that these dogs had hypersensitive to CJ pollen, which might be a cause of atopic disease in dogs.


Subject(s)
Dermatitis, Contact/veterinary , Dog Diseases , Pollen , Rhinitis, Allergic, Seasonal/veterinary , Allergens , Animals , Dermatitis, Contact/diagnosis , Dogs , Female , Japan , Male , Rhinitis, Allergic, Seasonal/diagnosis , Skin Tests/veterinary , Trees
11.
Biosci Biotechnol Biochem ; 59(3): 420-4, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7766179

ABSTRACT

We constructed an assay system to measure the annealing activity that is one of the functional features of nuclear proteins, using ssDNAs derived from M13 phage recombinants which contained a complementary 406-bp portion each. Histone H1 variants were purified from porcine thymus by separation of chromatin, extraction with 5% perchloric acid, and reversed-phase HPLC. Three types of histone H1 variants were found by analysis of amino acid composition and on SDS-PAGE. All of these could promote the annealing. According to Hill's analysis all had similar numbers of binding sites to DNA strands but dissociation constants and annealing activity were different. The number of binding sites, dissociation constants, and annealing activity were changed by dephosphorylation of histone H1 variants. This result suggests that histone H1 variants have different affinities for DNA molecules and ssDNA-annealing activity, which is regulated by phosphorylation.


Subject(s)
Histones/chemistry , Thymus Gland/chemistry , Amino Acids/analysis , Animals , Chromatography, High Pressure Liquid , Cloning, Molecular , DNA, Single-Stranded/drug effects , Electrophoresis, Polyacrylamide Gel , Histones/isolation & purification , Kinetics , Phosphorylation , Swine
12.
Scand J Immunol ; 40(6): 669-74, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7997857

ABSTRACT

We attempted to establish a null cell line from NZB x NZW(B/W)F1 mice in order to investigate a regulatory role of null cells during polyclonal B cell activation in autoimmune diseases. NB2.2, a representative subclone of resulting null cell lines, was maintained in long-term tissue culture with 10% mouse ConA supernatant (MCAS). Interestingly, the cell free supernatant of the NB2.2 cells (NB-CFS) showed marked synergistic effects on IgM secretion by B cells induced by IL-5. In addition, NB-CFS had the ability to augment the production of autoantibodies against bromelain-treated mouse red blood cells (BrMRBC) and single-stranded DNA (ssDNA) by B cells induced by IL-5. To determine whether NB2.2 cells induce polyclonal B cell activation and autoantibody generation in vivo, BALB/c mice were injected with NB2.2 cells. The results showed that the level of anti-ssDNA antibodies in sera of BALB/c mice injected with NB2.2 cells was significantly higher than that of control BALB/c mice injected with FDC-P2 cells. In addition, splenic B cells from mice injected with NB2.2 cells significantly proliferated in vitro in response to IL-4 and IL-5, and produced anti-ssDNA antibodies in the presence of IL-5. These results suggest that NB2.2, a null cell line established from B/WF1 mice, produces mediators capable of promoting polyclonal B cell activation and inducing autoantibody secretion, and that this kind of null cell may play an important role in the pathogenesis of autoimmune diseases.


Subject(s)
Antibodies, Antinuclear/biosynthesis , Lymphocytes, Null/immunology , Animals , B-Lymphocytes/immunology , Cell Line , Culture Media, Conditioned , DNA, Single-Stranded/immunology , Female , Flow Cytometry , Hemolytic Plaque Technique , Immunoglobulin M/biosynthesis , Interleukin-5/physiology , Lymphocyte Activation/immunology , Mice , Mice, Inbred NZB , Mice, Inbred Strains , Spleen/cytology
13.
Plant J ; 5(1): 111-22, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8130795

ABSTRACT

Two cDNA clones, cATMPK1 and cATMPK2, encoding MAP kinases (mitogen-activated protein kinases) have been cloned from Arabidopsis thaliana and their nucleotide sequences have been determined. Putative proteins encoded by ATMPK1 and ATMPK2 genes, designated ATMPK1 and ATMPK2, contain 370 and 376 amino acid residues, respectively, and are 88.7% identical at the amino acid sequence level. ATMPK1 and ATMPK2 exhibit significant similarity to rat ERK2 (49%) and Xenopus MAP kinase (50%). The amino acid residues corresponding to the sites of phosphorylation (Thr-Glu-Tyr) that are involved in the activation of MAP kinases are conserved in ATMPK1 and ATMPK2. Northern blot analysis indicates that the ATMPK1 and ATMPK2 mRNAs are significantly present in all the organs except seeds. Genomic Southern blot analysis suggests that there are a few additional genes that are related to ATMPK1 and ATMPK2 in the Arabidopsis genome. Purified Xenopus MAP kinase kinase (MAPK kinase) phosphorylates ATMPK1 and ATMPK2 proteins that have been expressed in Escherichia coli, activating these enzymes. A rapid and transient activation of 46-kDa protein kinase activity that phosphorylated myelin basic protein (MBP) was detected when auxin-starved tobacco BY-2 cells were treated with synthetic auxin, 2,4-dichlorophenoxyacetic acid (2,4-D). Protein kinase activities which phosphorylated the recombinant ATMPK2 protein also increased rapidly after auxin treatment in the auxin-starved BY-2 cells. These results suggest that auxin may function as an activator of plant MAP kinase homologues, as do various mitogens in animal systems.


Subject(s)
Arabidopsis Proteins , Arabidopsis/genetics , Indoleacetic Acids/physiology , Mitogen-Activated Protein Kinases , Protein Serine-Threonine Kinases/genetics , Protein-Tyrosine Kinases/genetics , 2,4-Dichlorophenoxyacetic Acid/pharmacology , Amino Acid Sequence , Animals , Arabidopsis/enzymology , Base Sequence , Cells, Cultured , Cloning, Molecular , DNA , DNA, Complementary , Enzyme Activation , Escherichia coli , Glycogen Synthase Kinase 3 , Mitogen-Activated Protein Kinase 1 , Mitogen-Activated Protein Kinase Kinases , Molecular Sequence Data , Phosphorylation , Plants, Toxic , Polymerase Chain Reaction , Protein Kinases/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein-Tyrosine Kinases/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Nicotiana/enzymology , Xenopus
14.
J Biochem ; 111(4): 456-9, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1618735

ABSTRACT

The complex of an adzuki bean subtilisin inhibitor (ASI-II) with its target enzyme, prepared at pH 7.6, was subjected to reversed-phase HPLC in a trifluoroacetic acid-acetonitrile system. Two peptide fragments derived from the reactive site-modified ASI-II were obtained. The analyses of the amino acid composition and sequence of these two fragments revealed that one corresponded to the region from the amino-terminal Lys to the reactive site P1 Ala and the other, to the region from the reactive site P1' Asp to the carboxyl-terminal Gly of the inhibitor. Although neither fragment alone showed inhibitory activity against subtilisin, an equimolar mixture of both fragments was found to inhibit strongly the target enzyme, as did the intact inhibitor. Thus, it was suggested that the two fragments have strong specific affinity with each other, regenerating the reactive site-modified ASI-II, to inhibit the target enzyme.


Subject(s)
Peptide Fragments/chemistry , Subtilisins/antagonists & inhibitors , Amino Acids/analysis , Binding Sites , Chromatography, High Pressure Liquid , Fabaceae , Macromolecular Substances , Peptide Fragments/metabolism , Plants, Medicinal
15.
Yakugaku Zasshi ; 112(2): 115-23, 1992 Feb.
Article in Japanese | MEDLINE | ID: mdl-1517975

ABSTRACT

It has been reported that the methanol extract from the bark of Acer nikoense MAXIM. (AN) and the fractions separated from this extract showed the protection for liver injuries induced by carbontetrachloride (CCl4) in rat. On the other hand, the evidence manifested that the fractions of the callus of young branches from AN were recognized to have protective effects on the CCl4-induced liver injuries in rat. In this study, the protective activities of the fractions extracted from the callus of AN were investigated on the alpha-naphthylisothiocyanate (ANIT)-induced liver injuries in rat. The protectively active principles on the ANIT-induced liver injuries were found in the ether soluble fraction. The components of the protective effect were purified by repeated silica gel chromatographies. One of the protective substances in this fraction was identified to be beta-sitosterol. The protective fractions on the ANIT-induced liver injuries showed the protective effects on ANIT-induced cholestasis, but did not show cholagogic effects.


Subject(s)
Cholestasis/prevention & control , Liver Diseases/prevention & control , Plant Extracts/therapeutic use , 1-Naphthylisothiocyanate , Animals , Chemical and Drug Induced Liver Injury , Cholagogues and Choleretics , Cholestasis/chemically induced , Male , Plant Extracts/pharmacology , Rats , Rats, Inbred Strains , Trees
16.
Cell Immunol ; 139(2): 386-98, 1992 Feb.
Article in English | MEDLINE | ID: mdl-1733510

ABSTRACT

The mechanism of polyclonal B cell activation in autoimmune diseases was investigated by using an autoreactive B cell clone established by somatic hybridization with B cells derived from NZB X NZW (B/W) F1 mice. Briefly, splenic B cells from B/W F1 mice were fused with M12.4.1, a mutant of a B cell line, in the presence of polyethylene glycol and DMSO. NW47.7, a subclone of a resulting hybridoma, expresses B cell surface antigens on the cell membrane, namely IAd, IgM, B220, the receptors for the C3 fragment of complement (C3R), and the Fc portion of IgG (Fc gamma R). It also possesses a receptor molecule for mouse red blood cells treated with bromelain (Br-MRBC) on its surface, by rosette-forming assay with Br-MRBC. In contrast, parental M12.4.1 does not express IAd and IgM on the cell membrane, and does not bind to Br-MRBC under the same conditions. Thus, it is likely that NW47.7 may be an autoreactive B cell clone specific for Br-MRBC. Interestingly, NW47.7 was induced to generate a significant number of IgM-secreting cells when treated with Br-MRBC and rIL-5. Furthermore, mAb against IAd molecules, but not IAk and KdDd, markedly inhibited the differentiative effect of polyclonal activators such as LPS and rIL-5. Also, when MHC identical irradiated B cells were added to the culture of NW47.7 as a stimulator, the induction of IgM-producing cells was greatly augmented, but this augmenting effect was lost by interfering with direct contact of NW47.7 cells with stimulator B cells using a semipermeable membrane, as well as by the addition of mAb against IAd molecules. In addition, irradiated NW47.7, but not M12.4.1, by itself could enhance the secretion of IgM by NW47.7 as a stimulator, but this enhancing effect markedly decreased in the presence of anti-IAd mAb. The present results suggest that surface IA molecules on B cells are involved during the differentiative response to polyclonal activators, and may directly provide a differentiative signal for maturation of B cells into IgM-secreting cells.


Subject(s)
Autoimmunity/immunology , B-Lymphocytes/immunology , Histocompatibility Antigens Class II/immunology , Animals , B-Lymphocytes/drug effects , Cell Differentiation , Cells, Cultured , Clone Cells/drug effects , Clone Cells/immunology , Female , Hybrid Cells , Interleukin-5/pharmacology , Lipopolysaccharides , Lymphocyte Activation/drug effects , Mice , Mice, Inbred BALB C , Mice, Inbred NZB
17.
Yakugaku Zasshi ; 111(10): 585-91, 1991 Oct.
Article in Japanese | MEDLINE | ID: mdl-1812278

ABSTRACT

The decoctions extracted from the bark and leaf of Acer nikoense Maxim. (AN) have been used as a folk medicine for eye-wash and hepatic disease. As previously reported, the methanol extract from the bark of AN and the fractions of the methanol extract have protective effects for liver injury induced by carbon tetrachloride (CCl4) in rats. In this study, protective effects of the fractions extracted from the callus of AN were investigated on CCl4-induced liver injury in rat. The active principles for the protection of CCl4-induced liver injury were recognized in a fraction (EF 3-3) obtained by using silica gel chromatography (solvent: CHCl3-MeOH-H2O). The components were further fractionated by silica gel chromatography followed by gel filtration (solvent: CHCl3-MeOH). In addition, the mechanism of the protective action against liver injury induced by CCl4 was also examined. The fractions with protective effects in vivo showed the inhibitory effects on CCl4-dependent lipid peroxidation in microsomal fraction in vitro.


Subject(s)
Carbon Tetrachloride Poisoning/drug therapy , Chemical and Drug Induced Liver Injury/drug therapy , Plants, Medicinal , Animals , Carbon Tetrachloride Poisoning/metabolism , Chemical and Drug Induced Liver Injury/metabolism , Depression, Chemical , In Vitro Techniques , Lipid Peroxides/metabolism , Male , Microsomes, Liver/metabolism , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Rats , Rats, Inbred Strains
18.
J Biochem ; 106(6): 1003-8, 1989 Dec.
Article in English | MEDLINE | ID: mdl-2628417

ABSTRACT

The complete amino acid sequence of a major molecular form of subtilisin inhibitor from adzuki beans (Vigna angularis) was established by manual analysis using 4-N,N-dimethylaminoazobenzene-4'-isothiocyanate (DABITC). Sequencing was performed on the peptides which were derived by digesting the inhibitor with lysyl-endopeptidase and Staphylococcus aureus V8-protease. The inhibitor consisted of 92 amino acid residues and the molecular weight was calculated to be 10,800. A minor form of subtilisin inhibitor was found, which lacked the amino-terminal 19 residues of the major one. Comparison of amino acid sequences revealed that the adzuki bean subtilisin inhibitors were 29-68% homologous in sequence to the inhibitors of so-called "potato inhibitor I family."


Subject(s)
Plant Proteins , Protease Inhibitors , Amino Acid Sequence , Fabaceae , Molecular Sequence Data , Peptide Fragments/isolation & purification , Plants, Medicinal , Seeds , Sequence Homology, Nucleic Acid , Serine Endopeptidases/metabolism
19.
Clin Immunol Immunopathol ; 53(1): 78-86, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2788547

ABSTRACT

Splenic B cells of BALB/c mice were fused with 2.52M, a mutant of a B cell line, in the presence of polyethylene glycol and dimethyl sulfoxide. AT73.14 a subclone of a resulting hybridoma, expresses B cell surface antigens on the cell membrane, namely IAd, IgM, B220, and receptors for C3 fragment of complement (C3R), the Fc portion of IgG (Fc gamma R), and interleukin 2 (IL-2R). It also possesses a receptor molecule for mouse red blood cells treated with bromelain (Br-MRBC) on its surface, by rosette-forming assay with Br-MRBC. In contrast, parental 2.52M does not express IAd on the cell membrane and does not bind to Br-MRBC on the same conditions. Thus, it is likely that AT73.14 may be an autoreactive B cell clone specific for Br-MRBC. Interestingly, AT73.14 could generate a significant number of IgM-secreting cells when treated with Br-MRBC; this was followed by a marked decrease in the expression of B cell surface markers on the cell membrane. In addition, this differentiative response of the cells greatly augmented in the presence of B151-TRF, a B cell differentiation factor, although B151-TRF alone showed only a marginal effect on the generation of IgM-secreting cells. The result suggests that this kind of an autoreactive B cell clone may provide a good model for the study on the mechanism of autoimmune responses.


Subject(s)
B-Lymphocytes/immunology , Erythrocytes/immunology , Hybridomas/immunology , Animals , Antigens, Differentiation, B-Lymphocyte/analysis , Autoantigens/immunology , B-Lymphocytes/drug effects , Bromelains/pharmacology , Cell Fusion , Clone Cells/drug effects , Clone Cells/immunology , Erythrocytes/drug effects , Hybridomas/drug effects , Immunoglobulin M/biosynthesis , Interleukin-4 , Interleukins/pharmacology , Lymphocyte Activation , Mice , Mice, Inbred BALB C
20.
J Nucl Med ; 29(4): 451-9, 1988 Apr.
Article in English | MEDLINE | ID: mdl-3351600

ABSTRACT

In order to select the optimal vasodilator for the treatment of patients with congestive heart failure (CHF), the acute effects of three vasodilators (isosorbide dinitrate (ISDN) 5 mg, nifedipine 10 mg, and prazosin 1 mg) on peripheral capacitance and resistance vessels (CV and RV) were evaluated by a newly devised radionuclear technique (Study 1). Thirty-six patients with chronic CHF were divided into Group A (ejection fraction (EF) greater than or equal to 35%, n = 20, mean EF: 47.2 +/- 6.5%) and B (EF less than 35%, n = 16, mean EF: 24.8 +/- 7.1%). ISDN produced the strongest CV dilatation (25% in both groups). Nifedipine reduced RV tone in Groups A and B (14% and 27%, respectively), and CV tone in Group A (6%). Prazosin had the most prominent effects on both vessels in Group B. From these results, it appeared: (a) ISDN is indicated for the cases with increased CV tone, (b) nifedipine is suitable for those with increased RV tone, (c) in cases of increased tone in both vessels, nifedipine (when EF greater than or equal to 35%) or prazosin (when EF less than 35%) is optimal. To evaluate the validity of this assignment, 49 subjects with CHF were divided into Group 1 (n = 16, increased CV tone), Group 2 (n = 17, increased RV tone), and Group 3 (n = 16, increased CV and RV tone) in Study 2. In Group 1, the changes of all indexes were not significantly different between the subjects treated with optimal drug based on the assignment (subgroup P) and those with a non-optimal drug (subgroup N) after 2 wk of therapy. In Group 2, however, improvements of RV tone, EF, and exercise duration in subgroup P were greater than those in subgroup N (31 versus 10%, 21 versus 0%, 41 versus 14%, respectively). In Group 3, the results were the same as in Group 2 (34 versus 19%, 24 versus 8%, 26 versus 9%). These findings suggested that the selection of the optimal vasodilator based on peripheral hemodynamic evaluation with a newly devised radionuclear technique permits more effective treatment of chronic CHF.


Subject(s)
Arm/blood supply , Heart Failure/diagnostic imaging , Vasodilator Agents/therapeutic use , Aged , Blood Flow Velocity/drug effects , Blood Volume/drug effects , Female , Heart Failure/drug therapy , Heart Failure/physiopathology , Humans , Isosorbide Dinitrate/therapeutic use , Male , Middle Aged , Nifedipine/therapeutic use , Prazosin/therapeutic use , Radionuclide Imaging , Stroke Volume/drug effects , Vascular Resistance/drug effects , Veins/physiopathology
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