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1.
Cell Death Dis ; 6: e1606, 2015 Jan 22.
Article in English | MEDLINE | ID: mdl-25611381

ABSTRACT

Annexin A2 (ANXA2) expression is highly upregulated in many types of cancer. Although cell surface localization of ANXA2 has been reported to have a critical role in the progression and metastasis of a variety of tumors, including pancreatic cancer, the biological role of intracellular ANXA2 is not fully understood. Herein the role of intracellular ANXA2 was investigated in a pancreatic cancer cell line. We first determined whether ANXA2 is involved in NF-κB signaling pathways. ANXA2 bound to the p50 subunit of NF-κB in a calcium-independent manner, and the ANXA2-p50 complex translocated into the nucleus. Furthermore, ANXA2 increased the transcriptional activity of NF-κB in both the resting and activated states and upregulated the transcription of several target genes downstream of NF-κB, including that encoding interleukin (IL)-6, which contributes to anti-apoptotic signaling. In Mia-Paca2 cells, we determined the effects of wild-type ANXA2 and an ANXA2 mutant, Y23A, which suppresses the cell surface localization, on upregulation of NF-κB transcriptional activity and secretion of IL-6. Both wild-type and Y23A ANXA2 induced anti-apoptotic effects in response to treatment with tumor necrosis factor-α or gemcitabine. Based on these results, we suggest that ANXA2 mediates resistance to gemcitabine by directly increasing the activity of NF-κB. Collectively, these data may provide additional information about the biological role of ANXA2 in pancreatic cancer and suggest that ANXA2 is a potential biomarker for the drug resistance phenotype and a candidate therapeutic target for the treatment of pancreatic cancer.


Subject(s)
Annexin A2/metabolism , Deoxycytidine/analogs & derivatives , Intracellular Space/metabolism , Pancreatic Neoplasms/metabolism , Protein Subunits/metabolism , Signal Transduction/drug effects , Transcription Factor RelA/metabolism , Annexin A2/chemistry , Calcium/pharmacology , Cell Line, Tumor , Cell Nucleus/drug effects , Cell Nucleus/metabolism , Cell Survival/drug effects , Deoxycytidine/pharmacology , Drug Resistance, Neoplasm/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockdown Techniques , Genes, Neoplasm , Humans , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Protein Binding/drug effects , Protein Structure, Tertiary , Protein Transport/drug effects , Signal Transduction/genetics , Structure-Activity Relationship , Transcription, Genetic/drug effects , Tumor Necrosis Factor-alpha/pharmacology , Up-Regulation/drug effects , Gemcitabine
2.
Diabetes Obes Metab ; 17(2): 161-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25359298

ABSTRACT

AIM: To investigate the effects of LY2405319, an analogue of fibroblast growth factor 21 (FGF21), on glucose homeostasis in streptozotocin (STZ)-induced insulin-deficient mice (STZ mice). METHODS: Nine-week-old male C57BL/6J mice were administered a single intraperitoneal injection of STZ (150 mg/kg). One week later, after confirmation of hyperglycaemia, saline or LY2405319 (5 mg/kg) was injected subcutaneously daily for 4 weeks. Changes in glucose homeostasis, energy metabolism and brown adipose tissue (BAT) function were assessed. RESULTS: The STZ mice had elevated blood glucose and reduced plasma FGF21 levels, impaired glucose uptake in the BAT, and BAT mitochondria with absent or swollen cristae and fewer lipid vacuoles. LY2405319 significantly reduced blood glucose levels and this was associated with increased BAT glucose uptake and changes in gene expression and morphology, indicating improved mitochondrial lipid metabolism in the BAT. Importantly, the ability of LY2405319 to lower blood glucose in STZ mice was compromised after removing interscapular BAT. CONCLUSIONS: Our results show that LY2405319 reduces blood glucose levels in insulin-deficient diabetes by improving BAT metabolism. Additional studies investigating the therapeutic potential of FGF21 for the treatment of type 1 diabetes are warranted.


Subject(s)
Adipose Tissue, Brown/drug effects , Adipose Tissue, Brown/physiopathology , Blood Glucose/drug effects , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 1/drug therapy , Fibroblast Growth Factors/pharmacology , Animals , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Type 1/physiopathology , Homeostasis , Injections, Intraperitoneal , Insulin/deficiency , Male , Mice , Mice, Inbred C57BL , Mice, Inbred NOD , Streptozocin
3.
J Pediatr Urol ; 10(2): 233-6, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24206784

ABSTRACT

OBJECTIVE: During the last decade laparoscopy has increasingly been advocated as the primary investigative procedure for the management of the non-palpable testis. We reviewed the medical records in a consecutive series of boys with non-palpable testis to examine the contribution of the initial inguinal approach in the management of unilateral non-palpable testis. MATERIALS AND METHODS: Among the 183 consecutive patients with cryptorchidism from 2003 to 2012, there were 21 patients with unilateral and three with bilateral non-palpable testes. All unilateral patients then underwent inguinal and scrotal exploration through an inguinal incision. For those patients with an intra-abdominal peeping testis, the gonad was placed into the scrotum after meticulous cranial mobilization of the spermatic cord. RESULTS: Patient age ranged from 11 months to 144 months (mean age: 23 months). Among the 21 unilateral cases, testicular absence or atrophy was confirmed in seven patients with a scrotal nubbin in six, and blind-ending vas and vessels at the external inguinal ring in one patient. Among the remaining 14 patients with sizeable testes, 12 testes were intra-abdominal peeping testes and two testicles were seen within the distal inguinal canal, which may be missed on physical examination owing to patient obesity. The intra-abdominal peeping testicle had the opened processus vaginalis entering the internal ring in which testicle was found. These were fixed into the scrotum successfully by cranial mobilization of spermatic vessel sometimes cutting the internal oblique muscle and by Prentiss and Fowler-Stephen's maneuver. Diagnostic laparoscopy was done on three patients with bilateral cases. CONCLUSIONS: Given the result that most of nubbins are within the scrotum and testes with intra-abdominal peeping testes are fixed down safely into the scrotum, the inguinal approach may suffice for the management of unilateral non-palpable testis. Laparoscopy should be reserved for patients with bilateral non-palpable undescended testes.


Subject(s)
Cryptorchidism/diagnosis , Cryptorchidism/surgery , Inguinal Canal/surgery , Laparoscopy/statistics & numerical data , Orchiopexy/methods , Child, Preschool , Cohort Studies , Follow-Up Studies , Humans , Infant , Male , Orchiopexy/adverse effects , Patient Selection , Physical Examination/methods , Republic of Korea , Retrospective Studies , Risk Assessment , Severity of Illness Index , Treatment Outcome , Unnecessary Procedures
4.
J Oral Rehabil ; 39(8): 600-7, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22489919

ABSTRACT

The objective of this study was to assess the effects of the Korean National Denture Service (NDS) for poor elderly people requiring dentures on oral health-related quality of life (OHRQOL). Data from follow-up studies were collected from 439 subjects at eight public health centres who answered every question of a questionnaire, and the OHRQOL was measured at the baseline and at 3-month follow-up after receiving the NDS according to the type of denture provision. The multivariate linear mixed model with a public health centre as a random effect for the score change of Oral Health Impact Profile (OHIP)-14K was carried out to confirm the factors related to the improvement in OHRQOL. The mean OHIP-14K was 28.60 at the baseline time points, and there was a decrease in the OHIP-14 scores to 21.14 ± 12.52 at the 3-month follow-up of the removable partial denture beneficiaries. The changes in OHIP-14K among complete denture beneficiaries were 21.53 ± 12.01 for previously dentate subjects and 22.54 ± 11.12 for edentate subjects. The multivariate linear mixed model of dentate subjects demonstrated that the improvement in the OHRQOL was associated with the number of remaining teeth, satisfaction with denture and self-reported oral health status after 3 months. In the case of the edentate model, satisfaction with denture was the only factor related to the improvement in OHRQOL. This study revealed considerable improvement in OHRQOL among poor elderly people after NDS. Satisfaction with provision of dentures was associated with improvement in the OHRQOL.


Subject(s)
Dental Health Services/organization & administration , Denture, Complete/psychology , Denture, Partial, Removable/psychology , Health Status , Jaw, Edentulous, Partially , Quality of Life , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Jaw, Edentulous, Partially/psychology , Jaw, Edentulous, Partially/rehabilitation , Male , Mouth, Edentulous/psychology , Mouth, Edentulous/rehabilitation , Oral Health , Patient Satisfaction , Poverty , Republic of Korea , Self Report , Sickness Impact Profile , State Medicine
5.
Cancer Gene Ther ; 17(3): 180-91, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19798123

ABSTRACT

In this study, we analyzed the preclinical utility and antitumor efficacy of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) delivered by Ad-IU2, a prostate-specific replication-competent adenovirus (PSRCA), against androgen-independent prostate cancer. Through transcriptional control of adenoviral early genes E1a, E1b and E4, as well as TRAIL by two bidirectional prostate-specific enhancing sequences (PSES), the expression of TRAIL and adenoviral replication was limited to prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA)-positive cells. Ad-IU2 induced fivefold greater apoptosis selectively in PSA/PSMA-positive CWR22rv and C4-2 cells than an oncolytic adenoviral control. Furthermore, prolonged infection with Ad-IU2 reversed TRAIL resistance in LNCaP cells. Ad-IU2 showed superior killing efficiency in PSA/PSMA-positive prostate cancer cells at doses five- to eight-fold lower than required by a PSRCA to produce a similar effect; however, this cytotoxic effect was not observed in non-prostatic cells. As an enhancement of its therapeutic efficacy, Ad-IU2 exerted a TRAIL-mediated bystander effect through direct cell-to-cell contact and soluble factors such as apoptotic bodies. In vivo, Ad-IU2 markedly suppressed the growth of subcutaneous androgen-independent CWR22rv xenografts compared with a PSRCA at 6 weeks after treatment (3.1- vs 17.1-fold growth of tumor). This study shows the potential clinical utility of a PSRCA armed with an apoptosis-inducing ligand.


Subject(s)
Adenoviridae/genetics , Apoptosis/physiology , Genetic Vectors/genetics , Prostatic Neoplasms/therapy , TNF-Related Apoptosis-Inducing Ligand/physiology , Animals , Antigens, Surface/genetics , Antigens, Surface/metabolism , Apoptosis/genetics , Blotting, Western , Cell Line , Glutamate Carboxypeptidase II/genetics , Glutamate Carboxypeptidase II/metabolism , Humans , Male , Mice , Mice, Nude , Prostate-Specific Antigen/genetics , Prostate-Specific Antigen/metabolism , Prostatic Neoplasms/metabolism , TNF-Related Apoptosis-Inducing Ligand/genetics , TNF-Related Apoptosis-Inducing Ligand/metabolism
6.
Cell Mol Biol (Noisy-le-grand) ; 55 Suppl: OL1096-103, 2009 Feb 25.
Article in English | MEDLINE | ID: mdl-19267992

ABSTRACT

Vitamin D3 up-regulated protein 1 (VDUP1) is a tumor suppressor of which expression is reduced in a variety of cancer cells, and enforced expression inhibits the tumor cell proliferation. It inhibits the activity of thioredoxin, thus contributing cellular ROS generation. Since ROS is a critical factor for angiogenesis, we investigated the role of VDUP1 in angiogenesis and endothelial proliferation. The expression of VDUP1 was upregulated by overexpression of an oncogene, Ras. Enforced expression of VDUP1 increases ROS production and proliferation of Ras-overexpressing endothelial cells. Overexpression of VDUP1 increases the resistance to the anchorage-dependent cell death and tube formation of the Ras-overexpressing endothelial cell. In addition, the removal of ROS by ROS scavenger attenuates the effect of VDUP1 on tube formation. These results suggest that VDUP1 is involved in Ras-mediated angiogenesis via ROS generation in endothelial cells.


Subject(s)
Carrier Proteins/metabolism , Neovascularization, Physiologic , Reactive Oxygen Species/metabolism , Thioredoxins/metabolism , ras Proteins/metabolism , Animals , Carrier Proteins/genetics , Cell Line , Endothelial Cells/metabolism , Mice , Thioredoxins/genetics , Up-Regulation
7.
Oncogene ; 28(12): 1529-36, 2009 Mar 26.
Article in English | MEDLINE | ID: mdl-19219071

ABSTRACT

Far upstream element-binding protein-1 (FBP-1) binds to an upstream element of the c-myc promoter and regulates the c-myc mRNA level. Earlier, FBP-1 was identified as a candidate substrate of caspase-7. Here, we report that FBP-1 is cleaved by executor caspases, both in vitro and during apoptosis. Cleavage occurs at the caspase consensus site (DQPD(74)) located within the classical bipartite nuclear localization signal sequence. In cells subjected to apoptotic stimuli, the caspase-mediated cleavage of FBP-1 leads to its decreased presence in the nucleus, concomitant with the marked downregulation of c-Myc and its various target proteins. By contrast, cells transfected with a non-cleavable mutant of FBP-1 (D74A) maintain higher levels of c-Myc and are protected from apoptosis. On the basis of these results, we suggest that the oncogenic potential of c-Myc is 'switched off' after apoptosis induction as a consequence of the caspase-mediated cleavage of FBP-1.


Subject(s)
Apoptosis , Caspases/physiology , DNA Helicases/physiology , DNA-Binding Proteins/physiology , Genes, myc , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Survival , DNA Helicases/analysis , DNA-Binding Proteins/analysis , Female , Humans , RNA-Binding Proteins
8.
Cancer Gene Ther ; 16(1): 73-82, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18772902

ABSTRACT

Enzyme pro-drug suicide gene therapy has been hindered by inefficient viral delivery and gene transduction. To further explore the potential of this approach, we have developed AdIU1, a prostate-restricted replicative adenovirus (PRRA) armed with the herpes simplex virus thymidine kinase (HSV-TK). In our previous Ad-OC-TK/ACV phase I clinical trial, we demonstrated safety and proof of principle with a tissue-specific promoter-based TK/pro-drug therapy using a replication-defective adenovirus for the treatment of prostate cancer metastases. In this study, we aimed to inhibit the growth of androgen-independent (AI), PSA/PSMA-positive prostate cancer cells by AdIU1. In vitro the viability of an AI- PSA/PSMA-expressing prostate cancer cell line, CWR22rv, was significantly inhibited by treatment with AdIU1 plus GCV (10 microg ml(-1)), compared with AdIU1 treatment alone and also cytotoxicity was observed following treatment with AdIU1 plus GCV only in PSA/PSMA-positive CWR22rv and C4-2 cells, but not in the PSA/PSMA-negative cell line, DU-145. In vivo assessment of AdIU1 plus GCV treatment revealed a stronger therapeutic effect against CWR22rv tumors in nude mice than treatment with AdIU1 alone, AdE4PSESE1a alone or in combination with GCV. Our results demonstrate the therapeutic potential of specific-oncolysis and suicide gene therapy for AI-PSA/PSMA-positive prostate cancer gene therapy.


Subject(s)
Adenoviridae , Genes, Transgenic, Suicide , Oncolytic Virotherapy , Oncolytic Viruses , Promoter Regions, Genetic , Prostatic Neoplasms/therapy , Animals , Cell Line, Tumor , Humans , Male , Mice , Mice, Nude , Neoplasm Transplantation , Prostate-Specific Antigen/biosynthesis , Prostate-Specific Antigen/genetics , Prostatic Neoplasms/enzymology , Prostatic Neoplasms/genetics , Simplexvirus/enzymology , Simplexvirus/genetics , Thymidine Kinase/biosynthesis , Thymidine Kinase/genetics , Viral Proteins/biosynthesis , Viral Proteins/genetics
9.
J Oral Rehabil ; 33(5): 317-22, 2006 May.
Article in English | MEDLINE | ID: mdl-16629888

ABSTRACT

The purpose of this study was to compare the oral health related quality of life (OHRQoL) between older Korean adults with complete and partial removable dentures using oral health impact profile (OHIP). A pool of 4250 Korean older adults was identified by random stratification by area from the sample cohort of Korean National Survey of Oral Health in the year of 2000. Out of the potential pool, 445 subjects with removable partial dentures (RPDs) or complete dentures (CDs) agreed to be interviewed by telephone. Each question in the survey was about how frequently each event was experienced during the past 12 months. To analyse the association between OHIP scores and removable denture status, bivariable analysis and multiple linear regression analysis were used. RPD users showed higher scores on eight items than CD users. They were 'breath stale', 'food catching', 'sensitive teeth', 'toothache', 'tense', 'unable to brush teeth', 'less tolerant to family members' and 'irritable with others'. RPD users might be associated with higher scores of functional limitation, physical pain and psychological discomfort than CD users. RPD users had slight tendency to be associated with higher OHIP-49 score than CD users, but it was not statistically significant. The findings of the present study confirm that there is no general OHRQoL difference between RPD and CD users. But in the items and subscales of OHIP, RPD users might experience more impaired OHRQoL than CD users.


Subject(s)
Denture, Complete , Denture, Partial, Removable , Oral Health , Quality of Life , Age Distribution , Aged , Denture, Complete/adverse effects , Denture, Complete/psychology , Denture, Partial, Removable/adverse effects , Denture, Partial, Removable/psychology , Female , Health Status Indicators , Humans , Male , Middle Aged , Pain/etiology , Sex Distribution
10.
Nature ; 412(6845): 456-61, 2001 Jul 26.
Article in English | MEDLINE | ID: mdl-11473323

ABSTRACT

Extensive work on the maturation of lagging strands during the replication of simian virus 40 DNA suggests that the initiator RNA primers of Okazaki fragments are removed by the combined action of two nucleases, RNase HI and Fen1, before the Okazaki fragments join. Despite the well established in vitro roles of these two enzymes, genetic analyses in yeast revealed that null mutants of RNase HI and/or Fen1 are not lethal, suggesting that an additional enzymatic activity may be required for the removal of RNA. One such enzyme is the Saccharomyces cerevisiae Dna2 helicase/endonuclease, which is essential for cell viability and is well suited to removing RNA primers of Okazaki fragments. In addition, Dna2 interacts genetically and physically with several proteins involved in the elongation or maturation of Okazaki fragments. Here we show that the endonucleases Dna2 and Fen1 act sequentially to facilitate the complete removal of the primer RNA. The sequential action of these enzymes is governed by a single-stranded DNA-binding protein, replication protein-A (RPA). Our results demonstrate that the processing of Okazaki fragments in eukaryotes differs significantly from, and is more complicated than, that occurring in prokaryotes. We propose a novel biochemical mechanism for the maturation of eukaryotic Okazaki fragments.


Subject(s)
DNA-Binding Proteins/physiology , DNA/metabolism , Saccharomyces cerevisiae Proteins , Adenosine Triphosphatases/metabolism , DNA/genetics , DNA Helicases/metabolism , DNA Ligase ATP , DNA Ligases/metabolism , DNA, Single-Stranded/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Exodeoxyribonuclease V , Exodeoxyribonucleases/antagonists & inhibitors , Exodeoxyribonucleases/metabolism , RNA, Messenger/metabolism , Replication Protein A , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism
11.
Nucleic Acids Res ; 29(14): 3069-79, 2001 Jul 15.
Article in English | MEDLINE | ID: mdl-11452032

ABSTRACT

In order to gain insights into the structural basis of the multifunctional Dna2 enzyme involved in Okazaki fragment processing, we performed biochemical, biophysical and genetic studies to dissect the domain structure of Dna2. Proteolytic digestion of Dna2 using subtilisin produced a 127 kDa polypeptide that lacked the 45 kDa N-terminal region of Dna2. Further digestion generated two subtilisin-resistant core fragments of approximately equal size, 58 and 60 kDa. Surprisingly, digestion resulted in a significant (3- to 8-fold) increase in both ATPase and endonuclease activities compared to the intact enzyme. However, cells with a mutant DNA2 allele lacking the corresponding N-terminal region were severely impaired in growth, being unable to grow at 37 degrees C, indicating that the N-terminal region contains a domain critical for a cellular function(s) of Dna2. Analyses of the hydrodynamic properties of and in vivo complex formation by wild-type and/or mutant Dna2 lacking the N-terminal 45 kDa domain revealed that Dna2 is active as the monomer and thus the defect in the mutant Dna2 protein is not due to its inability to multimerize. In addition, we found that the N-terminal 45 kDa domain interacts physically with a central region located between the two catalytic domains. Our results suggest that the N-terminal 45 kDa domain of Dna2 plays a critical role in regulation of the enzymatic activities of Dna2 by serving as a site for intra- and intermolecular interactions essential for optimal function of Dna2 in Okazaki fragment processing. The possible mode of regulation of Dna2 is discussed based upon our recent finding that replication protein A interacts functionally and physically with Dna2 during Okazaki fragment processing.


Subject(s)
Adenosine Triphosphatases/metabolism , DNA Helicases/metabolism , Deoxyribonuclease I/metabolism , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae/enzymology , Adenosine Triphosphatases/chemistry , Amino Acid Sequence , Animals , Binding Sites , Cell Line , DNA Helicases/chemistry , Deoxyribonuclease I/chemistry , Dimerization , Dose-Response Relationship, Drug , Endodeoxyribonucleases/genetics , Enzyme Activation/drug effects , Flap Endonucleases , Gene Expression Regulation, Fungal , Molecular Sequence Data , Molecular Structure , Molecular Weight , Mutation , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Phenotype , Protein Structure, Tertiary , Saccharomyces cerevisiae/growth & development , Sequence Deletion , Subtilisin/metabolism , Subtilisin/pharmacology , Temperature
12.
Arch Pharm Res ; 23(1): 46-9, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10728656

ABSTRACT

Two neolignan compounds, magnolol (5,5'-diallyl-2,2'-dihydroxybiphenyl, 1) and honokiol (5,5'-diallyl-2,4'-dihydroxybiphenyl, 2), were isolated from the stem bark of Magnolia obovata and evaluated for antifungal activity against various human pathogenic fungi. Compound 1 and 2 showed significant inhibitory activities against Trichophyton mentagrophytes, Microsporium gypseum, Epidermophyton floccosum, Aspergillus niger, Cryptococcus neoformans, and Candida albicans with minimum inhibitory concentrations (MIC) in a range of 25-100 microg/ml. Therefore, compound 1 and 2 could be used as lead compounds for the development of novel antifungal agents.


Subject(s)
Antifungal Agents/pharmacology , Biphenyl Compounds/pharmacology , Lignans , Humans , Microbial Sensitivity Tests
13.
Appl Environ Microbiol ; 66(2): 476-80, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10653706

ABSTRACT

Staphylokinase (SAK), a polypeptide secreted by Staphylococcus aureus, is a plasminogen activator with a therapeutic potential in thrombosis diseases. A Bacillus subtilis strain which is multiply deficient in exoproteases was transformed by an expression plasmid carrying a promoter and a signal sequence of subtilisin fused in frame with the sak open reading frame. However, the amount of SAK secretion was marginal (45 mg/liter). In contrast, disruption of the wprA gene, which encodes a subtilisin-type protease, strongly promoted the production of SAK in the stationary phase (181 mg/liter). In addition, the extracellular stability of mature SAK was dramatically enhanced. These data indicate a significant role of the wprA gene product in degrading foreign proteins, both during secretion and in the extracellular milieu.


Subject(s)
Bacillus subtilis/genetics , Bacterial Proteins , Metalloendopeptidases/metabolism , Serine Endopeptidases/genetics , Transformation, Bacterial , Bacillus subtilis/enzymology , Bacillus subtilis/growth & development , Electrophoresis, Polyacrylamide Gel , Enzyme Stability , Gene Deletion , Immunoblotting , Metalloendopeptidases/genetics , Plasmids/genetics , Recombinant Proteins/metabolism , Serine Endopeptidases/metabolism
14.
Phytother Res ; 13(8): 680-2, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10594938

ABSTRACT

With the aim of finding novel anti-human immunodeficiency virus agents from natural products, 93 MeOH extracts of Korean plants were screened for their inhibitory activities against HIV-1 protease. The most potent inhibition was shown by the root of Rodiola rosea with 70.4% inhibition at a concentration of 100 microg/mL.


Subject(s)
HIV Protease Inhibitors/pharmacology , HIV Protease/drug effects , HIV-1/enzymology , Medicine, Traditional , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Chromatography, High Pressure Liquid , HIV Protease Inhibitors/isolation & purification , Humans , Korea , Plant Extracts/isolation & purification
15.
Ann Nutr Metab ; 43(3): 173-80, 1999.
Article in English | MEDLINE | ID: mdl-10545673

ABSTRACT

The effects of dietary supplementation of a citrus bioflavonoid, naringenin, on the cholesterol metabolism were studied. For 42 days male rats were fed a 1% (wt/wt) high-cholesterol diet with or without a naringenin supplementation (0.1%, wt/wt) to study its effect on plasma lipid levels, hepatic lipid contents, activities of hepatic acyl coenzyme A:cholesterol O-acyltransferase (ACAT) and 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, and the excretion of fecal neutral sterols. Naringenin did not significantly alter the concentration of plasma triglycerides, but lowered the plasma cholesterol (3.80 vs. 3.12 mmol/l) concentration and the hepatic cholesterol content (70.3 vs. 54.0 mg/g) significantly (p < 0.05) compared to those of the controls. HMG-CoA reductase (1,879.0 vs. 1,715.0 pmol/min/mg) and ACAT activities (806.0 vs. 563.0 pmol/min/mg) were significantly lower in the naringenin-supplemented group than in controls. Naringenin supplementation caused a marked decrease in the excretion of fecal neutral sterols (242.9 mg/day) compared to the controls (521.9 mg/day). These results show that naringenin lowers the plasma and hepatic cholesterol concentrations by suppressing HMG-CoA reductase and ACAT in rats fed a high-cholesterol diet.


Subject(s)
Cholesterol/blood , Enzyme Inhibitors/pharmacology , Flavanones , Flavonoids/pharmacology , Hydroxymethylglutaryl CoA Reductases/metabolism , Sterol O-Acyltransferase/antagonists & inhibitors , Animals , Cholesterol/metabolism , Cholesterol, Dietary/administration & dosage , Feces , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Liver/metabolism , Male , Rats , Rats, Sprague-Dawley , Sterol O-Acyltransferase/metabolism , Sterols/metabolism
16.
Int J Vitam Nutr Res ; 69(5): 341-7, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10526779

ABSTRACT

The effects of the citrus bioflavonoid naringin were tested by using it as a supplement in a high-cholesterol diet. Male rats were fed for 42 days with a 1% (wt/wt) high cholesterol diet either with or without naringin-supplementation (0.1%, wt/wt) to study the effect on plasma lipid levels, hepatic lipid contents, hepatic enzyme activity, and the excretion of fecal neutral sterols. Naringin did not significantly alter the levels of plasma triglycerides, however, the levels of plasma cholesterol (3.80 +/- 0.31 mmol/L vs. 2.61 +/- 0.30 mmol/L, mean +/- SE; p < 0.05) and hepatic cholesterol (70.3 +/- 4.3 mg/g vs. 54.3 +/- 3.8 mg/g, mean +/- SD; p < 0.05) were significantly lowered compared to those of the control. HMG-CoA reductase (2487.0 +/- 210.0 pmole/min/mg vs. 1879.0 +/- 236.0 pmole/min/mg, mean +/- SE; p < 0.05) and ACAT (806.0 +/- 105.0 pmole/min/mg vs. 643.0 +/- 80.0 pmole/min/mg, mean +/- SE; p < 0.05) activities were both substantially lower in the naringin-supplemented group than in the control. The naringin supplementation markedly decreased the excretion of fecal neutral sterols (204.7 +/- 28.5 mg/day) compared to the control (521.9 +/- 53.9 mg/day). The combination of the inhibited HMG-CoA reductase (-24.4%) and ACAT (-20.2%) activities as a result of naringin supplementation could account for the decrease of fecal neutral sterols.


Subject(s)
Anticholesteremic Agents/pharmacology , Antioxidants/pharmacology , Cholesterol/blood , Flavanones , Flavonoids/pharmacology , Liver/enzymology , Animals , Dietary Supplements , Feces/chemistry , Hydroxymethylglutaryl CoA Reductases/metabolism , Male , Rats , Rats, Sprague-Dawley , Sterol O-Acyltransferase/metabolism
17.
Arch Pharm Res ; 22(4): 417-22, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10489885

ABSTRACT

Two new furanolignans (3, 5), together with three known lignans (1, 2, 4), were isolated from the stem of Lindera obtusiloba (Lauraceae). The structures of the compounds were determined as actifolin (1), pluviatilol (2), 5,6-dihydroxymatairesinol (3), (+)-syringaresinol (4), and (+)-9'-O-trans-feruloyl-5,5'-dimethoxylariciresinol (5) on the basis of physicochemical and spectroscopic evidences. Compounds 1, 2, 3, and 5 showed cytotoxicity against a small panel of human tumor cell lines with ED50 values of 3.40 to approximately 19.27 microg/ml.


Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Lignans/chemistry , Plants, Medicinal/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Chromatography, Gel , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Drug Screening Assays, Antitumor , Humans , Korea , Lignans/isolation & purification , Magnetic Resonance Spectroscopy , Mass Spectrometry , Spectrophotometry, Infrared
18.
J Nutr ; 129(6): 1182-5, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10356084

ABSTRACT

The cholesterol-lowering effects of tangerine peel extract and a mixture of two citrus flavonoids were tested. Male rats were fed a 1 g/100 g high-cholesterol diet for 42 d with supplements of either tangerine-peel extract or a mixture of naringin and hesperidin (0.5 g/100 g) to study the effects of plasma and hepatic lipids, hepatic enzyme activities, and the excretion of fecal neutral sterols. Both the tangerine-peel extract and mixture of two flavonoids significantly lowered the levels (mean +/- SE) of plasma (2.44 +/- 0. 59 and 2.42 +/- 0.31 mmol/L, vs. 3.80 +/- 0.28 mmol/L, P < 0.05), hepatic cholesterol (0.143 +/- 0.017 and 0.131 +/- 0.010 mmol/g vs. 0.181 +/- 0.003 mmol/g, P < 0.05), and hepatic triglycerides (0.069 +/- 0.007 and 0.075 +/- 0.006 mmol/g vs. 0.095 +/- 0.002 mmol/g, P < 0.05) compared to those of the control. The 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase (1565.0 +/- 106. 0 pmol. min-1. mg protein-1 and 1783.0 +/- 282 pmol. min-1. mg protein-1 vs. 2487.0 +/- 210.0 pmol. min-1. mg protein-1, P < 0.05) and acyl CoA: cholesterol O-acyltransferase (ACAT) activities (548.0 +/- 65.0 and 615.0 +/- 80.0 pmol. min-1. mg protein-1 vs. 806.0 +/- 105.0 pmol. min-1. mg protein-1, P < 0.05) were significantly lower in the experimental groups than in the control. These supplements also substantially reduced the excretion of fecal neutral sterols compared to the control (211.1 +/- 26.7 and 208.2 +/- 31.6 mg/d vs. 521.9 +/- 53.9 mg/d). The inhibition of HMG-CoA reductase and ACAT activities resulting from the supplementation of either tangerine-peel extract or a combination of its bioflavonoids could account for the decrease in fecal neutral sterol that appears to compensate for the decreased cholesterol biosynthesis in the liver.


Subject(s)
Cholesterol/metabolism , Citrus/chemistry , Flavonoids/pharmacology , Hydroxymethylglutaryl CoA Reductases/metabolism , Liver/metabolism , Plant Extracts/pharmacology , Sterol O-Acyltransferase/metabolism , Animals , Cholesterol/blood , Drug Combinations , Feces/chemistry , Lipid Metabolism , Lipids/blood , Liver/enzymology , Male , Rats , Rats, Sprague-Dawley , Sterols/analysis
19.
Planta Med ; 65(3): 261-3, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10232075

ABSTRACT

Two triterpenoid compounds, ursolic acid and uvaol, were isolated from Crataegus pinnatifida Bunge leaves. Ursolic acid inhibits chitin synthase II from S. cerevisiae with an IC50 value of 0.84 microgram/ml and the inhibition appears to be selective for chitin synthase II, whereas uvaol has no inhibitory activity up to 280 micrograms/ml. Oleanolic acid, alpha-hederin hydrate, and betulic acid inhibited the chitin synthase II activity under the same conditions with an IC50 of 5.6, 64.3, and 98.7 micrograms/ml, respectively.


Subject(s)
Chitin Synthase/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Rosales/chemistry , Triterpenes/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/isolation & purification , Saccharomyces cerevisiae/enzymology , Triterpenes/chemistry , Triterpenes/isolation & purification , Ursolic Acid
20.
Planta Med ; 65(1): 74-6, 1999 Feb.
Article in English | MEDLINE | ID: mdl-17260239

ABSTRACT

Fifteen lignans were isolated from the fruits of SCHIZANDRA CHINENSIS, the leaves of MACHILUS THUNBERGII, and the flower buds of MAGNOLIA DENUDATA. They were identified as gomisins, schizandrin, wuweizisu, schizantherin, licarins, and machilin, which inhibited rat liver ACAT with IC (50) values of 25-200 microM. Comisin N is the most potent inhibitor with IC (50) value of 25 microM in these lignans.

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