• The Korean Journal of Physiology
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• v.23 no.1
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• pp.13-21
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• 1989

The present study was designed to investigate i) the action of various nucleotides on membrane permeability of rat red blood cell and hepatocyte for $Na^{+}$ and $Rb^{+}$ ii) the characteristics of purinoceptors on these cell membranes. Blood from Sprague-Dawley rats was obtained by carotid arterial cannulation. Red blood cells were then washed 3 times with saline at $4{\circ}C$. Hepatic parenchymal cells were isolated from rat livers by using a modification of the Berry and Friend (1969) method. For the $Na^{+}$ influx studies, isolated RBC and hepatocyte were incubated in incubation medium containing $^{22}Na^{+}0.2\;{\mu}Ci/ml$ at $37^{\circ}C$. After various time intervals samples were removed from the incubation flask and washed out 3 times with ice-cold washing solutions. Cells were destroyed by adding Triton X-100 and TCA solution. After centrifugation, the supernatants were assayed for $^{22}Na^{+}$ by gamma counter. $^{86}Rb^{+}$ was used to simulate $K^{+}$ in these $K^{+}efflux$ studies. Isolated hepatocytes were incubated for 60 min in the loading solution containing $^{86}Rb^{+}\;10\;{\mu}Ci/ml$ at $37^{\circ}C$. After loading, the cells washed out 3 times by centrifugation with washing solution. The cells were incubated in buffer solution at $37^{\circ}C$. At intervals thereafter, samples were removed and centrifuged. The supernatants were analyzed for $^{86}Rb^{+}$ by liquid scintillation counter. The main results of the experiments were: 1) ATP and ATPP increased in both $^{22}Na^{+}$ influx and $^{86}Rb^{+}$ efflux in the red blood cell. Although ADP showed a tendency to increase in RBC membrane permeability for $^{22}Na^{+}$ and $^{86}Rb^{+}$, the changes were not significantly different from the control. 2) The Significant changes in $^{22}Na^{+}$ and $^{86}Rb^{+}$ flux by ATP were also demonstrated in hepatocyte. ATPP and ADP showed a tendency to increase in hepatocyte membrane permeability for both ions. 3) Other nucleoside triphosphates-ITP, GTP and CTP-did not change in membrane permeability for $^{22}Na^{+}$ and $^{86}Rb^{+}$ in RBC and hepatocyte. In conclusion, not only ATP but also ATPP activate purinoceptors and change in membrane permeability for $Na^{+}$ and $K^{+}$. In order to activate purinoceptors on the cell membrane, the nucleotides have to possess intact adenine moiety and three phosphates or more in its molecule.

• Korean Journal of Pharmacognosy
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• v.27 no.2
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• pp.111-116
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• 1996

The components were isolated from the root of Astragalus membranaceus and their structures were characterized as 3,4-methylenedioxypyrrolealdehyde, $7-O-{\beta}-D-glucopyranosyl$ 7, 3'-dihydroxy-4'-methoxy isoflavone and a naphthalene derivative on the basis of spectral and physical methods. $7-O-{\beta}-D-glucopyranosyl$ 7, 3'-dihydroxy-4'-methoxy isoflavone and the naphthalene compound showed protective effect on $CC_{l4}-induced$ cytotoxicity in primary cultured rat hepatocytes.

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.58-64
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• 1990

The effects of ginseng saponins, G-Rbl and G-Rc on the rat liver LDH A-gene transcnptional activity was investigated during pro-replicative phase of rat liver after partial hepatectomy. Changes in LDH A-mRNA levels in regenerating rat liver after intraperitoneal administrations of G-Rbl of G-Rc were tested by slot blot hybridization methods. The results showed that G-Rbl (1 mg/100g B.W) and G-Rc (1 ma/100g B.W) caused marked increases of LDH A-mRNA contents by respectively 1.9- and 1.5-fold in rat liver at 5·hours after partial hepatectomy. Dose dependent effect of G-Rbl and G-Rc (1-25 mg/100g B.W) on the LDH A-mRNA levels on regenerating rat liver were also analyzed. The maximal in- creases of liver LDH A-mRNA levels were observed with the doses of 1 mg for G-Rbl and 5 mg for G-Rc However, when the administration doses of G-Kbl and G-Rc were increased to 20 mg, G-Rbl caused a marked decrease of LDH A-mRNA level to 61% of those in sham-operated rat liver In contrast, G-Rc slightly decreased the liver LDH A-mRNA contents by 30% as compared to those of the maximum value but still maintained 22% higher LDH A-mRNA levels then those of sham-operated rate liver. On the basis of these experimental results, we conclude that ginseng saponin, G-Rb 1 and G·Rc have stimulatory effect at the lower concentration (1 mg/100g B.W) and inhibitory effect at the higher concentration (20 moi loos 5.W) on the LDH A-gene transcription during regeneration of rat liver, Additionally we also investigated the stimulatory effects of ginsenosides on the protein and DNA synthetic activities in hepatocyte primary cell cultures isolated from regenerating rat liver. Both of G·Rc and -Re increased the synthetic rates of hepatocytes proteins and DNA at the administration doses of 50 ug and 100 ug/3 ml/dish respectively representing 1.3-1.6 fold increases. From these results we postulate that G-Rc and -Re may have a mitogen enhancer activity for the hepatocyte proliferation during rat liver regeneration period. Keywords Inductive effects of ginsenosides, G-Rb, -Rc, and -Re, rat LDH A-gene transcription, the sin thetic rate of proteins and DNA in regeneration rat liver.

• Journal of Ginseng Research
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• v.14 no.2
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• pp.200-206
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• 1990

The effects of ginseng saponins, SRbl and G-Rc on the rat liver LDH A-gene transcriptional activity was investigated during prereplicative phase of rat liver after partial hepatectomy. Changes in LDH A-mRNA levels in regenerating rat liver after intraperitoneal administrations of G-Rbl or 'G-Rc were tested by slot blot hybridization methods. The results showed that G-Rbl (1 mg/100g B.W) and G-Rc (1 mg/100g B.W) caused marked increases of LDH A-mRNA contents by respectively 1.9- and 1.5-fold in rat liver at 5-hours after partial hepatectomy Dose dependent elect of G-Rbl and G-Rc (1-25 mg/ 100g B.W) on the LDH A-mRNA levels on regenerating rat liver were also analyzed. The maximal increases of liver LDH A-mRNA levels were observed with the doses of 1 mg for G-Rbl and 5 mg for G-Rc. However, when the administration doses of G-Rbl and G-Rc were increased to 20 mg, G-Rbl caused a marked decrease of LDH A-mRNA level to 61% of those in sham-operated rat liver. In contrast, G-Rc slightly decreased the liver LDH A-mRNA contents by 30% as compared to those of the maximum value but still maintained 22% higher LDH A-mRNA levels then those of sham-operated rate liver. On the basis of these experimental results, we conclude that ginseng saponin, G-Rbl and G-Rc have stimulatory effect at the lower concentration (1 mg/ 100g B.W) and inhibitory effect at the higher concentration (20 mg/ 100g B.W) on the LDH A-gene transcription during regeneration of rat liver. Additionally we also investigated the stimulatory effects of ginsenosides on the protein and DNA sinthetic activities in hepatocyte primary cell cultures isolated from regenerating rat liver. Both of G-Rc and -Re increased the synthetic rates of hepatocytes proteins and DNA at the administration doses of 50 us and 100 $\mu\textrm{g}$/3 ml/dish respectively representing 1.3-1.6 fold increases. From these results we postulate that G-Rc and -Re may have a mitogen ehincer activity for the hepatocyte proliferation during rat liver regeneration period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.2
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• pp.246-255
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• 1996

To develop a natural antioxidative peptide, the gelatin was extracted from fish (Yellowfin sole) skin by hot $water(50^{\circ}C)$ extraction method and hydrolyzed with Alcalase, pronase and collagenase through a continuous 3-step membrane reactor. Each step enzymatic hydrolysates were determined the antioxidative activity and their synergistic effects, compared with $\alpha-tocopherol$ and butylated hydroxytoluene (BHT). Also, we tried to investigate the antioxidative disposition of peptide which was successfully separated by gel filtration, ion-exchange chromatography, and HPIC in cultured rat hepatocytes intoxicated with tert-butyl hydroperoxide (TBHP). Second step enzymatic hydrolysate (SSEH) among all hydrolysates and $\alpha-tocoperol$ was showed the strongest antioxidative activity. The optimum concentration of antioxidative activity for SSEH was $1\%(w/w)$ in linoleic acid. The synergistic effects were increased in using the hydrolysate with tocopherol and BHT. In the presence of the peptide isolated from SSEH, supplemented hepatocytes exposed to TBHP showed that delayed cell killing and decreased significantly the lipid peroxidation, compared with hepatocytes not cultured with isolated peptide.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.577-582
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• 1997

Effects of four citrus flavonoids, hesperidin, naringin and their aglycones on phosphatidate phosphohydrolase(PAP, EC 3.1.3.3) activity were examined using isolated rat microsomes as an enzyme source. In addition, these flavonoids were tested to see whether they exert any influence on the proliferation and growth in cultured human hepatocytes HepG2 cells. Flavonoids at concentration up to $10{-4}M$ had no significant effect on the number of cells and cell proliferation by MTT cell growth assay method, whereas aglycone flavonoids, hesperetin and narigenin, at concentration of $10{-3}M$ significantly inhibited cell proliferation. Hesperetin inhibited PAP activity in a dose-dependent manner starting at concentration of $10{-5}M$. Narigenin at concentration of $10{-2}M$ inhibited PAP activity markedly, while the other flavonoids did not show any significant effect. The present study, therefore, demonstrated that aglycone flavonoids exerted portent effects on PAP activity and on cell proliferation.

• Toxicological Research
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• v.25 no.1
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• pp.29-33
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• 2009

Phellinus gilvus (PG) is a widely used mushroom for health promotion. We studied the hepatoprotective effect of the polysaccharide aqueous extract of PG (PGP) against carbon tetrachloride ($CCl_4$)-induced liver injury in rats. Sprague Dawley rats were divided into 5 groups: Normal control, $CCl_4$ control, PGP 50, 100, and 200 mg/kg + $CCl_4$. The levels of serum biochemical parameters, liver lipid peroxide and antioxidant enzymes, and histological appearances were evaluated. The $CCl_4$-induced increments of alanine aminotransferase, asparate aminotransferase, and alkaline phosphatase levels in serum were significantly decreased by PGP-pretreatments. The PGP dose-dependently decreased hepatic malondialdehyde formations in $CCl_4$-treatment groups. Hepatic antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) were elevated by PGP in $CCl_4$-treatment groups. Histopathological evaluation of liver showed that the loss of hepatocytes, fatty changes, swelling and extensive necrosis of hepatocytes in centrilobular regions of the $CCl_4$-treated rats were ameliorated by PGP pretreatment. The PGP has hepatoprotective and antioxidative effects in $CCl_4$-induced liver injury of rat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.78-83
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• 2011

The flower of Chrysanthemum morifolium Ramat. with antioxidant, anticancer, and anti-inflammatory functions has been a widely used traditional herb as a healthy beverage and medicine. The aim of the present study was to investigate a herb tea consisting of C. morifolium Ramat., Corni fructus and Schizandra chinensis Baillon for its hepatoprotective activity against $CCl_4$-induced toxicity in freshly isolated rat hepatocytes and antigenotoxic effect against oxidative stress induced DNA damage in human leukocytes. Three different compositions of the herb tea (Mix I, II, and III) were prepared by extracting with water at $90^{\circ}C$. Freshly isolated rat hepatocytes were exposed to $CCl_4$ along with/without various concentrations of each tea. Protection of rat primary cells against $CCl_4$-induced damage was determined by the MTT assay. The significant antihepatotoxic effect of the tea was shown in Mix I and II. The increased transaminase (AST and/or ALT) release in media of $CCl_4$ treated hepatocytes was significantly lowered by all the teas tested. The effect of the tea on DNA damage in human leukocytes was evaluated by Comet assay. All teas showed a protective effect against $H_2O_2$-induced DNA damage. From these results, it is assumed that herb tea based on C. morifolium Ramat., Corni fructus and Schizandra chinensis Baillon exerted antihepatotoxic and antigenotoxic effects.

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.157-164
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• 2000

The major components were isolated from the n-hexane, EtOAc and BuOH extract of Galla Rhois(Rhus Javanica Linne). Their structures were characterized as syringic acid, gallic acid methylester, protocatechuic acid, gallic acid and 1, 2, 3, 4, $6-penta-O-galloyl-{\beta}-D-glucose$. This study was carried out to investigate the biological activities of isolated compounds. Five compounds were tested for hepatoprotective effects on CCl4-induced cytotoxicity in primary cultured rat hepatocytes and antioxidative effect on Ferric-Thiocyanate method and TBA method. As a result, isolated five compounds showed stronger antioxidative activity than tocopherol, and the antioxidative activity of gallic acid methylester, protocatechuic acid and syringic acid were similar to that of BHA on Ferric-Thiocyanate method. Specially 1, 2, 3, 4, $6-penta-O-galloyl-{\beta}-D-glucose$ showed stronger effect of lipid-peroxidation inhibition than BHA. Gallic acid appeared stronger inhibitory effect of malondialdehyde on TBA method. Hepatoprotective effect of 1, 2, 3, 4, $6-penta-O-galloyl -{\beta}-D-glucose$ was similar or even higher than that of glycyrrhizin on primary cultured rat hepatocyte cytotoxicity.

• Archives of Pharmacal Research
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• v.18 no.4
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• pp.256-261
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• 1995

The elevation of intracellular $Ca^{2+}$ in various tissue through oxidative stress induced by menadione has been well documented. Increase of $Ca^{2+}$ level inplatelets results in aggreaction of patelets. To test the hypothesis that menadione-induced $Ca^{2+}$ elevations can play a role in platelet aggregation, we have studied the effect of menadione on aggragation of platelets isolated from female rats. Treatment with menadione to platelet rich plasma (PRP), which proved to be 60% as determined by aggregometry. however, exposure of PRP to menadione leads to a loss of cell viability, as measured by lactae dehydrogenase (LDH) leakage, suggesting that menadione might induce cell lysis rather than aggregation of platelets. Turbidty changes induced by menadione were unaffected by addition ofl dicoumarol, which is a quinone reducellular factions of patelets. These data, which indicate an absence of the QR detoxifying pathway, suggest that platelets may be more susceptible to menadione-induced cytotoxicity than certain other cell, as hepatocytes.