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2.
Cryobiology ; 33(3): 300-10, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8689887

ABSTRACT

The study was designed to examine the suitability of immature horse oocytes for vitrification. Immature oocytes derived from slaughtered horse ovaries were transferred to a vitrification solution (EFS; 40% ethylene glycol, 18% Ficoll, and 0.3 M sucrose in modified phosphate-buffered saline) directly (Groups 1 and 4) or were first exposed to 20% ethylene glycol solution for 10 min (Groups 2 and 5) or 20 min (Groups 3 and 6). Oocytes were handled at 20 degrees C (Groups 1, 2, and 3) or 30 degrees C (Groups 4, 5, and 6). After vitrification and warming, their viability was assessed by maturation culture for 32 h. The percentages of oocytes reaching the metaphase II stage after the in vitro maturation in Groups 2, 3, 5, and 6 (16.0, 16.7, 10.0. and 8.2%, respectively) were higher than those in Groups 1 and 4 (2.2 and 1.9%, respectively). In untreated control oocytes, 55.6% completed meiosis in vitro. Transmission electron microscopy was used to compare the fine structure of vitrified oocytes (treated as Group 2) with those of untreated control oocytes and EFS-exposed, nonvitrified oocytes (n = 10 each). The viability of EFS-exposed oocytes, assessed by in vitro maturation, was 27.7%. Vitrification induced some ultrastructural changes, such as the swelling of mitochondria together with reduced matrix density, the destruction of communication between oocytes and their surrounding cumulus cells, and the presence of vacuoles located in the periphery of the ooplasm. However, these changes were not always observed. Exposure of the oocytes to EFS solution induced similar ultrastructural changes in mitochondria and cell-cell communication but to a lesser extent. However, the exposure to EFS induced vacuoles in the periphery of the ooplasm to the same extent as did the vitrification. Thus, immature horse oocytes can be cryopreserved by vitrification with EFS solution. Reduced viability of EFS-exposed and/or vitrified horse oocytes may relate to morphological changes such as destruction of the intercellular communications between cumulus cells and oocytes.


Subject(s)
Cryopreservation/methods , Oocytes , Animals , Cell Survival , Cryoprotective Agents , Ethylene Glycol , Ethylene Glycols , Evaluation Studies as Topic , Female , Ficoll , Horses , In Vitro Techniques , Microscopy, Electron , Oocytes/growth & development , Oocytes/ultrastructure , Sucrose , Temperature , Time Factors
3.
Antiviral Res ; 25(1): 57-66, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7529015

ABSTRACT

Three flavans, daphnodorins A, B and C isolated from Dahpne odora THUNB. were tested for their abilities to inhibit human immunodeficiency virus type 1 (HIV-1(IIIB)) replication in MT-4 cells. The effective concentrations (EC50) of daphnodorins A, B and C against HIV-1-induced cytolysis were 0.26 +/- 0.08, 1.8 +/- 0.6 and 3.6 +/- 0.5 micrograms/ml, respectively. Also these three compounds showed inhibitory effects of p24 antigen in human peripheral blood lymphocytes. As compared with 2',3'-dideoxycytidine 5'-triphosphate (DDC-TP), daphnodorin A and daphnodorin C had relatively weak inhibitory effects on the reverse transcriptase of HIV-1, while daphnodorin B did not show any inhibitory effect at concentrations up to 1000 micrograms/ml. These three compounds showed marked inhibitory effects on syncytium formation between HIV-1(IIIB)-infected and uninfected MOLT-4 (clone 8) cells at 3-30 micrograms/ml without inducing cytotoxicity. The concentrations of the compounds blocking syncytium formation were consistent with the effective concentrations (EC50) against HIV-induced cytolysis of MT-4 cells. These results, differing from reverse transcriptase inhibitors, suggest that the daphnodorins exert their anti-HIV-1 activity through inhibition of early events of viral replication including adsorption of the virions to the cells or the subsequent entry.


Subject(s)
Antiviral Agents/pharmacology , Benzopyrans/pharmacology , HIV-1/drug effects , Cell Fusion/drug effects , Cytopathogenic Effect, Viral/drug effects , Giant Cells/drug effects , HIV Reverse Transcriptase , HIV-1/physiology , Humans , Lymphocytes/drug effects , Lymphocytes/virology , Reverse Transcriptase Inhibitors , Tumor Cells, Cultured , Virus Replication/drug effects
4.
Rinsho Ketsueki ; 35(1): 49-53, 1994 Jan.
Article in Japanese | MEDLINE | ID: mdl-8139102

ABSTRACT

A 57-year-old male patient with multiple myeloma showed an aggressive course with characteristic clinical features: rapid progression of plasmacytoma in the thoratic cavity, high serum levels of lactate dehydrogenase (LDH), which is usually not elevated in myeloma patients, and neutrophil infiltration in pleural effusion. Despite treatment with vincristine, doxorubicin and dexamethasone, the tumor mass had become non-responsive to chemotherapy and been increasing in size in correlating with the increase of serum levels of LDH. The patient died of respiratory failure 4 months after treatment. Thus the serum level of LDH is thought to be a useful clinical marker to monitor disease activity as well as other markers such as monoclonal immunoglobulin and beta 2-microglobulin. To investigate the cause of neutrophil infiltration into pleural effusion, we cultured plasma cells obtained from the effusion for 3 days in serum-free medium and examined the activity of neutrophil chemotaxis in the culture supernatant. The results showed chemotactic activity in the supernatant as high as in positive controls stimulated with a chemotactic factor, formyl-methionyl leucyl phenyl-alanine, suggesting that tumor cells produced neutrophil chemotactic factor(s).


Subject(s)
Chemotaxis, Leukocyte , L-Lactate Dehydrogenase/blood , Multiple Myeloma/pathology , Pleural Effusion/pathology , Drug Resistance , Humans , Male , Middle Aged , Multiple Myeloma/enzymology , Neutrophils , Tumor Cells, Cultured
5.
Biochem Pharmacol ; 44(10): 1947-51, 1992 Nov 17.
Article in English | MEDLINE | ID: mdl-1333200

ABSTRACT

The effect of naturally occurring hydroxystilbene, 3,3',4,5-tetrahydroxystilbene (piceatanol), and its derivatives on gastric H+, K(+)-ATPase was studied. Piceatanol inhibited H+, K(+)-ATPase in a dose-dependent manner. The 50% inhibition value was 4.3 x 10(-6) M. It was found from the kinetic study that the inhibition of the enzyme by piceatanol was competitive with respect to ATP and was noncompetitive with respect to K+. Piceatanol also effectively inhibited gastric acid secretion. However, methylation of phenolic hydroxy groups of piceatanol resulted in a complete loss of inhibition of the enzyme and acid secretion, suggesting the role of phenolic hydroxy groups in the inhibition. The study on hydroxystilbene derivatives also showed that phenolic hydroxy groups are important in the interaction with H+, K(+)-ATPase and that stilbenes with neighbouring hydroxy groups are the most effective inhibitors.


Subject(s)
Gastric Mucosa/drug effects , Proton Pump Inhibitors , Stilbenes/pharmacology , Adenosine Triphosphate/pharmacology , Animals , Binding, Competitive , Dogs , Dose-Response Relationship, Drug , Gastric Acid/metabolism , Gastric Mucosa/enzymology , Gastric Mucosa/metabolism , Kinetics , Potassium/pharmacology , Sodium-Potassium-Exchanging ATPase/antagonists & inhibitors , Structure-Activity Relationship , Swine
6.
Res Commun Chem Pathol Pharmacol ; 77(2): 227-40, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1439191

ABSTRACT

The effects of a new chalcone derivative, xanthoangelol E, isolated from Angelica keiskei Koidzumi, on arachidonic acid metabolism in the gastric antral mucosa and platelet of the rabbit were examined. When gastric antral mucosal slices were incubated with xanthoangelol E (0.05-1.0 mM), there was no significant effect on the production of prostaglandin (PG) E2, PGF2 alpha and their metabolites. On the other hand, this compound inhibited effectively the production of thromboxane B2 and 12-hydroxy-5,8,10-heptadecatrienoic acid from exogenous arachidonic acid in platelets, and the concentration required for 50% inhibition (IC50) was approximately 5 microM. The formation of 12-hydroxy-5,8,10,14-eicosatetraenoic acid was also reduced by this drug (IC50, 50 microM). These results suggest that xanthoangelol E has the potential to modulate arachidonic acid metabolism in platelets and that this action may participate in some pharmacological effect of the plant.


Subject(s)
Arachidonic Acid/blood , Arachidonic Acid/metabolism , Blood Platelets/drug effects , Chalcone/analogs & derivatives , Gastric Mucosa/drug effects , 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid , Adenosine Triphosphatases/antagonists & inhibitors , Animals , Blood Platelets/enzymology , Blood Platelets/metabolism , Chalcone/pharmacology , Fatty Acids, Unsaturated/blood , Fatty Acids, Unsaturated/metabolism , Gastric Mucosa/enzymology , Gastric Mucosa/metabolism , Hydroxyeicosatetraenoic Acids/blood , Hydroxyeicosatetraenoic Acids/metabolism , Male , Pyloric Antrum , Rabbits , Thromboxane B2/blood , Thromboxane B2/metabolism
7.
Biochem Pharmacol ; 44(1): 33-7, 1992 Jul 07.
Article in English | MEDLINE | ID: mdl-1321629

ABSTRACT

The effects of cassigarol A, a naturally occurring polyphenol, on gastric H+,K(+)-ATPase and gastric acid secretion were studied. Cassigarol A inhibited H+,K(+)-ATPase and K-stimulated p-nitrophenyl phosphatase from hog gastric mucosa with 50% inhibition of 1.2 x 10(-6) and 6.3 x 10(-6) M, respectively. The kinetic study showed that the inhibition of H+,K(+)-ATPase by cassigarol A was competitive with respect to ATP and non-competitive with respect to K+. Cassigarol A inhibited both H+,K(+)-ATPase-mediated proton transport and 2-deoxy-D-glucose-induced acid secretion. On the other hand, cassigarol A acetate, in which phenolic hydroxy groups are acetylated, was not effective in the inhibition of enzyme activity and acid secretion. These results indicate that cassigarol A is a potent inhibitor of gastric H+,K(+)-ATPase, that the anti-secretory activity of cassigarol A is related to the inhibition of H+,K(+)-ATPase and that an important moiety of cassigarol A in the interaction with the enzyme is the phenolic hydroxy groups.


Subject(s)
Adenosine Triphosphatases/antagonists & inhibitors , Flavonoids , Gastric Acid/metabolism , Gastric Mucosa/enzymology , Phenols/pharmacology , Plants, Medicinal/chemistry , Polymers/pharmacology , Adenosine Triphosphate/metabolism , Animals , Dogs , H(+)-K(+)-Exchanging ATPase , Kidney/enzymology , Kinetics , Male , Phenols/isolation & purification , Polymers/isolation & purification , Polyphenols , Rats , Sodium-Potassium-Exchanging ATPase/antagonists & inhibitors , Swine
8.
Chem Pharm Bull (Tokyo) ; 39(12): 3353-4, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1726077

ABSTRACT

3,3',4,5'-Tetrahydroxystilbene (I) and 3,3',4,5'-tetrahydroxybibenzyl (II), isolated from the heartwood of Cassia garrettiana Craib (Leguminosae), showed inhibitory effects on antigen-induced histamine release from rat peritoneal mast cells in vitro. The inhibitory effect of I (IC50 = 30.2 microM) was much stronger than that of II (greater than 100 microM). Compound II, as well as I (IC50 = 7.3 microM) reported previously, also inhibited the histamine release from human peripheral basophils induced by anti-immunoglobulin E (IgE) in vitro, and its IC50-value was 68.0 microM. These results suggest that the trans-olefin structure in the molecule may be necessary for I to have an inhibitory effect on histamine release. Considering that disodium cromoglycate did not show any significant inhibitory effect on anti-IgE-induced histamine release from human basophils, the strong inhibitory effects of I in both tests are of considerable interest.


Subject(s)
Antigens/immunology , Bibenzyls/pharmacology , Cassia/chemistry , Histamine Antagonists/pharmacology , Histamine Release/drug effects , Plants, Medicinal , Stilbenes/pharmacology , Animals , Basophils/drug effects , Basophils/metabolism , Humans , In Vitro Techniques , Male , Mast Cells/drug effects , Mast Cells/metabolism , Rats , Rats, Inbred Strains
9.
Chem Pharm Bull (Tokyo) ; 39(6): 1604-5, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1934181

ABSTRACT

Two chalcones, xanthoangelol (I) and 4-hydroxyderricin (II), isolated from the root of Angelica keiskei KOIDZUMI (Umbelliferae) showed antibacterial activity against gram-positive pathogenic bacteria. The activity of I on Micrococcus luteus IFO-12708 (minimum inhibitory concentration (MIC), 0.76 microgram/ml) was the same potency as that of gentamicin, which is used as a standard. Although the activity of both chalcones on plant-pathogenic bacteria was lower than that of streptomycin sulfate, used as a positive control, they also exhibited growth-inhibitory effects. The antibacterial activity of I isolated from Angelica keiskei KOIDZUMI is being reported here for the first time. The growth-inhibitory effect of II on plant-pathogenic bacteria is also reported for the first time in this paper.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Chalcone/analogs & derivatives , Plants, Medicinal/chemistry , Chalcone/pharmacology , Microbial Sensitivity Tests
10.
Chem Pharm Bull (Tokyo) ; 39(3): 805-7, 1991 Mar.
Article in English | MEDLINE | ID: mdl-1712675

ABSTRACT

3,3',4,5'-Tetrahydroxystilbene (I), a constituent of Cassia garrettiana, strongly inhibited the anti-IgE-induced histamine release from human basophils in vitro at concentrations of 3 to 30 microM. Considering that disodium cromoglycate showed no significant inhibitory activity in this assay method, the strong effect of I should be emphasized.


Subject(s)
Basophils/drug effects , Cassia/analysis , Histamine Release/drug effects , Immunoglobulin E/immunology , Plants, Medicinal , Stilbenes/pharmacology , Basophils/immunology , Histamine Release/immunology , Humans , In Vitro Techniques
11.
J Pharm Pharmacol ; 42(10): 723-6, 1990 Oct.
Article in English | MEDLINE | ID: mdl-1982146

ABSTRACT

Two chalcone derivatives, xanthoangelol (1) and 4-hydroxyderricin (II) isolated from Angelica keiskei Koidzumi, inhibited pig gastric H+, K(+)-ATPase with IC50 values of 1.8 and 3.3 microM, respectively. The inhibition by I or II was competitive with respect to ATP and was non-competitive with respect to K+ I and II also inhibited K+, stimulated p-nitrophenyl phosphatase, with IC50 values of 1.3 and 3.5 microM, respectively. Proton transport in-vitro was inhibited by I or II, in a dose-dependent manner, 1 at 100 mg kg-1, i.p. significantly inhibited acid secretion and the formation of stress-induced gastric lesions. These results suggest that the antisecretory effect of 1 is due to the inhibition of gastric H+, K(+)-ATPase.


Subject(s)
Adenosine Triphosphatases/antagonists & inhibitors , Chalcone/analogs & derivatives , Chalcone/pharmacology , Microsomes/enzymology , Plants, Medicinal/analysis , 4-Nitrophenylphosphatase/antagonists & inhibitors , Animals , Gastric Acid/metabolism , Gastric Mucosa/drug effects , Gastric Mucosa/enzymology , H(+)-K(+)-Exchanging ATPase , In Vitro Techniques , Male , Potassium/pharmacology , Rats , Rats, Inbred Strains , Spectrometry, Fluorescence , Swine
20.
Biochim Biophys Acta ; 834(2): 224-9, 1985 Apr 25.
Article in English | MEDLINE | ID: mdl-3922420

ABSTRACT

The effects of various coumarins (i.e. esculetin, daphnetin and fraxetin) on the formation of the 5-lipoxygenase product, 5-HETE, and the cyclooxygenase product, HHT, were studied. Esculetin (6,7-dihydroxycoumarin) was found to inhibit the formation of 5-HETE more strongly than HHT; its concentrations for 50% inhibition (IC50) were 1.46 +/- 1.02 microM for the formation 5-HETE and 57.3 +/- 17.3 microM for the formation of HHT. Daphnetin (7,8-dihydroxycoumarin) and fraxetin (6-methoxy-7,8-dihydroxycoumarin) also inhibited the formation of the 5-lipoxygenase product, 5-HETE, and the cyclooxygenase product, HHT; their IC50 values were, respectively, 6.90 +/- 2.07 microM and 2.57 +/- 0.088 microM for the formation of 5-HETE and 139.0 +/- 30.0 microM and 532.5 +/- 33.0 microM for the formation of HHT. The monohydroxy coumarin derivatives umbelliferone (7-hydroxycoumarin) and scopoletin (6-methoxy-7-hydroxycoumarin) and the coumarin glucosides fraxin (6-methoxy-7,8-dihydroxycoumarin 8-O-D-glucoside) and esculin (6,7-dihydroxycoumarin 6-O-D-glucoside) also inhibited the formation of 5-HETE, though less strongly. 4-Hydroxycoumarin and coumarin had no effect on either 5-lipoxygenase or cyclooxygenase at concentrations of up to 1 mM. Esculetin inhibited the formation of 5-HETE noncompetitively. In contrast, the dimethoxycoumarin fraxidin (6,8-dimethoxy-7-hydroxycoumarin) inhibited the formation of HHT more strongly than the formation of 5-HETE at a concentration of 1 mM.


Subject(s)
Arachidonic Acids/blood , Coumarins/pharmacology , Fatty Acids, Unsaturated/biosynthesis , Hydroxyeicosatetraenoic Acids/biosynthesis , Neutrophils/metabolism , Animals , Arachidonate Lipoxygenases , Arachidonic Acid , Arachidonic Acids/metabolism , Catalysis , Fatty Acids, Unsaturated/blood , Hydroxyeicosatetraenoic Acids/blood , Lipoxygenase/blood , Neutrophils/enzymology , Prostaglandin-Endoperoxide Synthases/blood , Rats
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