• YAKHAK HOEJI
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• v.49 no.2
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• pp.140-146
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• 2005

Candida albicans, a polymorphic fungus, causes systemic and local infections. Recent reports show that the fungus is a main etiological agent for the arthritis. For trea tment, antifungal drugs and/or rheumatoid drugs are used, but resistance and side effects limit application of the drugs. In search of new sources for treatment of the fungal arthritis, we choose Egb 761 (extract of Ginkgo leaves 761), one of the most popular over-the-counter herbal medicines. The Egb 761 contains two major ingredients such as terpene and flavonoid. In the present study, we examined if the terpene portion of Egb 761 had anti-inflammatory activity against C.albicans-caused arthritis. The terpene was extracted with combination of methanol and water from the Egb 761, followed by gel-permeation chromatography. Presence of terpene was determined by the Salkowski colorimetric method and HPLC analysis. For an animal model of inflammation induction, mice were given an emulsion form of C.albicans cell wall mixed with Complete Freund's Adjuvant (CFA) by footpad-injection. Results showed that intraperitoneal administration of the water-soluble portion that contained terpene and flavonoid reduced the inflammation. Whereas the terpene had anti-inflammatory activity, flavonoid portion had no such activity, For determination of possible mechanism of the activity, the terpene seemed to be suppression of nitric oxide (NO) production from LPS-treated macrophages. Taken together the Ginkgo terpene may have anti-inflammatory effect against C.albicans-caused arthritis, possibly by blocking NO production.

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.508-513
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• 2006

The effect of acteoside, a phenylpropanoid glycoside isolated from Clerodendron trichotomum Thunberg, on histamine and arachidonic acid release was investigated in RBL 2H3 cells. Histamine was dose-dependently released from RBL 2H3 cells by melittin, arachidonic acid and thapsigargin. In extracellular $Ca^{2+}-free$ solution, basal secretion of histamins increased by two fold. The response of histamine release to melittin and thapsigargin in $Ca^{2+}-free$ solution was significantly decreased, whereas the response to arachidonic acid was significantly increased as compared with those in normal solution. Acteoside inhibited histamine release induced by melittin, arachidonic acid and thapsigargin in a dose-dependent manner in the presence or absence of extracellular $Ca^{2+}$. However, the inhibitory activity of acteoside was more potent in normal solution than that in $Ca^{2+}-free$ solution. These data suggest that inhibitory mechanism of acteoside on histamine release may be related to extracellular $Ca^{2+}$. On the other hand, acteoside significantly inhibited arachidonic acid release and prostaglandin $E_2$ production Induced by $0.5\;{\mu}M$ melittin. It is possible that acteoside may be developed as an anti-inflammatory agent.

• Molecules and Cells
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• v.27 no.2
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• pp.149-157
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• 2009

In both gram-positive and several gram-negative bacteria, the transcription of dnaK and groE operons is negatively regulated by HrcA; however, the mechanism modulating HrcA protein activity upon thermal stress remains elusive. Here, we demonstrate that HrcA is modulated via reduction and oligomerization in vitro. Native-PAGE analysis was used to reveal the oligomeric structure of HrcA. The oligomeric HrcA structure became monomeric following treatment with the reducing agent dithothreitol, and this process was reversed by treatment with hydrogen peroxide. Moreover, the mutant HrcA C118S exhibited reduced binding to CIRCE elements and became less oligomerized, suggesting that cysteine residue 118 is important for CIRCE element binding as well as oligomerization. Conversely, HrcA mutant C280S exhibited increased oligomerization. An HrcA double mutant (C118S, C280S) was monomeric and exhibited a level of oligomerization and CIRCE binding similar to wild type HrcA, suggesting that cysteine residues 118 and 280 may function as checks to one another during oligomer formation. Biochemical fractionation of E. coli cells overexpressing HrcA revealed the presence of HrcA in the membrane fraction. Together, these results suggest that the two HrcA cysteine residues at positions 118 and 280 function as reduction sensors in the membrane and mediate oligomerization upon stress.

• Environmental Mutagens and Carcinogens
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• v.25 no.1
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• pp.6-12
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• 2005

Many compounds might become activated after absorption of UV light energy. In some cases, the resulting molecule may undergo further biological reaction of toxicological relevance related especially to the photo-carcinogenicity resulting from photo-genotoxicity. However, no regulatory requirements have been issued with the exception of guideline issued by the Scientific Committee of Cosmetology, Commission of the European Communities (SCC/EEC) on the testing of sunscreens for their photo-genotoxicity. Thus, the objectives of this study are to investigate the utility of photo-Ames assay for detecting photo-mutagens, and to evaluate its ability to predict rodent photo-carcinogenicity. Photo-Ames assay was performed on five test substances that demonstrated positive results in photo-carcinogenicity tests: 8-methoxypsoralen (photoactive substance that forms DNA adducts in the presence of ultraviolet A irradiation), chlorpromazine (an aliphatic phenothiazine an a-adr-energic blocking agent), lomefloxacin (an antibiotic in a class of drugs called fluoroquinolones), anthracene (a tricyclic aromatic hydrocarbon a basic substance for production of anthraquinone, dyes, pigments, insecticides, wood preservatives and coating materials) and retinoic acid (a retinoid compound closely related to vitamin A). Out of 5 test substances, 3 showed a positive outcome in photo-Ames assay. With this limited data set, an investigation into the predictive value of this photo-Ames test for determining the photo-carcinogenicity showed that photo-Ames assay has relatively low sensitivity (the ability of a test to predict carcinogenicity). Thus, to determine the use of in vitro genotoxicity tests for prediction of carcinogenicity,' several standard photo-genotoxicity assays should be compared for their suitability in detecting photo-genotoxic compounds.

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.618-624
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• 2010

This study was conducted to establish the in vitro seed germination of Loranthus tanakae. A factorial experiment evaluated the effects of seed storage duration (0, 8, 16 weeks), media (MS, SH, White, WPM), presence of viscin, GA3, gelling agent and concentrations. Seed germinated after one week culture in in vitro condition and produced radicles. In vitro seed germination was optimal when the seeds removed viscin placed on SH medium (69%) and the addition of 0.35% gelrite (75%) in the same medium. As seed storage duration was expanded to 8 or 16 weeks, in vitro seed germination rate was reduced rapidly. Holdfasts were also produced at the side of radicles. The important factors to produce holdfast and haustorium was kind of media as an optimal condition in White medium without any supplements to be shown 98% and 8% respectively. Process of in vitro germination of Loranthus tanakae was followed to radicle elongation, holdfast development and then haustorium formation sequencially.

• Carbon letters
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• v.8 no.3
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• pp.184-190
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• 2007

Carbon Nano Tubes could be either metallic or semi-conducting in nature, depending on their diameter. Its photocatalytic behavior has given an impetus to use it as an anti-microbial agent. More than 95% Escherichia coli and Staphylococcus aureus bacteria got killed when exposed to Carbon Nano Tubes for 30 minutes in presence of sunlight. Carbon Nano Tubes are supposed to have smooth surface on to which it accumulates positive charges when exposed to light. The surface that is non illuminated has negative charge. At the cellular level microorganisms produce negative charges on the cell membrane, Therefore damaging effect of multi walled carbon nano tubes (exposed to light) on the microorganisms is possible. In this paper, photo catalytic killing of microbes by multi walled carbon nano tubes is reported. Killing was due to damage in the cell membrane, as seen in SEM micrographs. Moreover biochemical analysis of membrane as well as total cellular proteins by SDS PAGE showed that there was denaturation of membrane proteins as well as total proteins of both the microbes studied. The killed microbes that showed a decrease in number of protein bands (i.e. due to breaking down of proteins) also showed an increase in level of free amino acids in microbes. This further confirmed that proteins got denatured or broken down into shorter units of amino acids. Increased level of free amino acids was recorded in both the microbes treated with multi walled carbon nano tubes and sunlight.

• Genomics & Informatics
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• v.2 no.1
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• pp.45-52
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• 2004

The self-splicing group I intron from Tetrahymena thermophila has been demonstrated to perform splicing reaction with its substrate RNA in the trans configuration. In this study, we explored the potential use of the trans-splicing group I ribozymes to replace a specific RNA with a new RNA that exerts any new function we want to introduce. We have chosen thymidine phosphorylase (TP) RNA as a target RNA that is known as a valid cancer prognostic factor. Cancer-specific expression of TP RNA was first evaluated with RT-PCR analysis of RNA from patients with gastric cancer. We determined next which regions of the TP RNA are accessible to ribozymes by employing an RNA mapping strategy, and found that the leader sequences upstream of the AUG start codon appeared to be particularly accessible. A specific ribozyme recognizing the most accessible sequence in the TP RNA with firefly luciferase transcript as a 3' exon was then developed. The specific trans-splicing ribozyme transferred an intended 3' exon tag sequence onto the targeted TP transcripts, resulting in a more than two fold induction of the reporter activity in the presence of TP RNA in mammalian cells, compared to the absence of the target RNA. These results suggest that the Tetrahymena ribozyme can be a potent anti-cancer agent to modify TP RNAs in tumors with a new RNA harboring anti-cancer activity.

• Journal of Microbiology and Biotechnology
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• v.21 no.7
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• pp.766-775
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• 2011

We investigated the effect of high molecular weight polygamma- glutamic acid (hm ${\gamma}$-PGA) on adiposity and lipid metabolism of rats in the presence of an obesity-inducing diet. Thirty-two Sprague-Dawley rats were fed either a normal-fat (11.4% kcal fat, NFC) or high-fat (51% kcal fat, HFC) diet. After 5 weeks, half of each diet-fed group was treated with hm ${\gamma}$-PGA (NFP or HFP) for 4 weeks. The HFC group had significantly higher body weight, visceral fat mass, fasting serum levels of total cholesterol, LDL cholesterol, and leptin, and lower serum HDL cholesterol level compared with those of the NFC group (p < 0.05). Treatment with hm ${\gamma}$-PGA decreased body weight gain and perirenal fat mass (p<0.05), fasting serum total cholesterol, and mRNA expression of glucose-6- phosphate dehydrogenase (G6PD), regardless of dietary fat contents (p < 0.01). However, hm ${\gamma}$-PGA increased serum HDL cholesterol in the HFC group (p < 0.05). In vitro, 3-hydroxy-3-methylglutaryl coenzyme-A (HMGCoA) reductase activity was suppressed by the addition of hm ${\gamma}$-PGA. In agreement with observations in animal study, the supplementation of hm ${\gamma}$-PGA (150 mg/day) to 20 female subjects in an 8-week double-blind, placebocontrolled study resulted in a tendency to decrease total cholesterol and LDL cholesterol concentrations. We thus conclude that dietary supplementation of hm ${\gamma}$-PGA may act as a hypocholestrolemic agent, secondary to its inhibitor effect on HMG-CoA reductase, and decrease abdominal adiposity by decreasing hepatic lipogenesis. The present study is an important first step in establishing the effect of hm ${\gamma}$-PGA on cholesterol levels in rats and humans.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.5
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• pp.251-254
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• 2006

Schizandrae Fructus has been used for controlling respiratory allergic or inflammatory diseases in folk medicine and their components, schizandrin, schizandrin-A and gomisin-A were reported to have diverse biological effects. In this study, we investigated whether schizandrin, schizandrin-A and gomisin-A affect adenosine triphosphate (ATP)-induced mucin secretion from cultured airway epithelial cells. Confluent primary hamster tracheal surface epithelial (HTSE) cells were metabolically radio labeled using $^{3}H-glucosamine$ for 24 h and chased for 30 min in the presence of varying concentrations of each agent to assess the effects on $^{3}H-mucin$ secretion. The results were as follows: 1) schizandrin significantly inhibited ATP-induced mucin secretion; 2) However, schizandrin-A and gomisin-A did not affect ATP-induced mucin secretion, significantly. We conclude that schizandrin can inhibit ATP-induced mucin secretion by directly acting on airway mucin-secreting cells. Therefore, schizandrin should further be investigated for the possible use as mucoregulators in the treatment of inflammatory airway diseases.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.6
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• pp.317-321
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• 2006

In this study, we investigated whether glycyrrhizin, prunetin and morroniside affect mucin secretion from cultured airway epithelial cells and compared the possible activities of these agents with the inhibitory action on mucin secretion by poly-L-lysine (PLL) and the stimulatory action by adenosine triphosphate (ATP). Confluent primary hamster tracheal surface epithelial (HTSE) cells were metabolically radiolabeled using $^{3}H-glucosamine$ for 24 h and chased for 30 min in the presence of varying concentrations of each agent to assess the effects on $^{3}H-mucin$ secretion. The results were as follows: 1) glycyrrhizin and morroniside increased basal mucin secretion from airway; 2) prunetin did not affect basal mucin secretion; 3) glycyrrhizin did not inhibit ATP-induced mucin secretion. We conclude that glycyrrhizin and morroniside can increase basal mucin secretion, by directly acting on airway mucin-secreting cells and suggest that two compounds be further investigated for the possible use as mild expectorants during the treatment of inflammatory airway diseases.