• 한국수산과학회지
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• 제31권6호
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• pp.889-894
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• 1998

해양오염의 진단을 위한 생화학적 오염지표 설정의 기초연구의 일환으로, 남해안의 양식장 오염도를 평가하기 위하여 오염도가 적은 동해안의 자연산 넙치를 대조군으로 하여 남해안 양식산 넙치 (Paralichthys olivaceus)의 혈액, 뇌조직 및 근육중의 활성산소에 의해 생성되는 LPO, 활성산소의 생성량 및 활성산소의 제거효소의 활성을 분석 평가하였다. 남해안 양식산 넙치의 뇌조직 및 근육중의 단백질 함량이 동해안의 포항의 자연산 넙치(대조군)의 단백질 함량 대비 각각 $19\~42\%$(뇌) 및 $25\~41\%$(근육)나 유의적으로 감소하였다. 남해안의 양식산 넙치의 혈청중의 LPO의 함량은 대조군으로 사용한 동해안 포항의 자연산 넙치의 혈청중의 LPO의 함량 대비 $5\~33\%$나 유의적으로 높았다. 넙치의 단백질 및 LPO의 함량에서 볼 때 남해안 시료채취해역의 오염도가 서해안 시료채취해역의 오염도에 비해 비교적 낮다는 사실을 확인할 수 있었다 남해안의 양식산 넙치의 혈청중의 $\cdot$OH의 생성량은 동해안 포항의 자연산 넙치 대비 각각 $4\~25\%$정도나 낮았다. 또한 남해안의 양식산 넙치의 혈청중의 SOD의 활성은 동해안 포항의 자연산 넙치 대비 $7\~31\%$나 낮았다. 이상의 결과에서 볼 때 넙치의 뇌조직 및 근육중의 단백질 함량과 혈청중의 LPO의 함량이 해양 오염의 지표로 사용할 수 것으로 기대된다 그렇지만, 넙치 혈청중의 $\cdot$OH 등의 활성산소나 SOD 등의 제거효소의 활성은 해양 오염의 지표로서 사용할 수 없을 것으로 판단된다.

• 한국식품영양학회:학술대회논문집
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• 한국식품영양학회 2000년도 춘계학술심포지엄
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• pp.13-20
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• 2000

Melatonin, a chemical mediator produced in the mammalian pineal gland and several other organ, is a ubiquitously acting antioxidant. It has been shown to scavenge the hydroxyl radical (ㆍOH), singlet oxygen ($^1$O$_2$) and the peroxynitrite anion (ONOO-). In addition, melatonin reportedly stimulates a number of antioxidative enzymes including glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase. Antioxidative effect of melatonin in pharmacological and physiological level was investigated using hepatocarcinogen 2-nitropropane (2-NP) and pinealectornized (Px) rats, respectively. Lipid peroxidation (LPO) as indicated by malondialdehyde and 4-hydroxyalkenals and DNA damage as indicated by 8-hydroxydeoxyguanosine (8-OH-dG) induced by 2-NP were prevented by melatonin. The degree of LPO and DNA damage in Px rats were higher than those of intact old and young ones suggesting the removal of pineal gland resulted in higher accumulation of oxidative damage.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.24-25
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• 2001

Persistent cellular oxidative stress and enhanced lipid peroxidation (LPO) of PUFAs, leading to macromolecular damage and disruption of signaling pathways, are implicated in the development of human malignancies and other chronic degenerative diseases. LPO generates by oxidation of linoleic acid (LA) or arachidonic acid ($\omega$ -6 PUPAs) reactive aldehydes, such as trans-4-hydroxy-2-nonenal, which form etheno $\varepsilon$ -DNA adducts in a variety of human tissues and thus can contribute to diet-related cancers.(omitted)

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1045-1047
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• 2006

Fabrication of $Mg_{95.75}Zn_1Y_3Yb_{0.25}$ bulk alloy has been performed through the consolidation of rapidly solidified ribbons. The $Mg_{95.75}Zn_1Y_3Yb_{0.25}$ bulk alloy exhibited excellent mechanical properties, high tensile yield strength of 530 MPa, and large elongation of 3 %. Microstructure of the alloy was characterized by equiaxed fine grains that consist of -Mg, long period ordered (LPO) structure phase, and $Mg_5RE$-type cubic compound. The strengthening of the alloys may be due to fine grains with LPO structure phase and $Mg_5RE$-type compound.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2011년도 춘계 학술발표회 및 심포지엄
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• pp.116-117
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• 2011

• Advances in Traditional Medicine
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• 제8권2호
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• pp.146-153
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• 2008

The present study is aimed at finding the influence of silymarin (a flavonoid) (25 mg/kg & 50 mg/kg) in streptozotocin (STZ)-induced diabetic rats. Type 2 diabetes was induced by single intraperitoneal injection of STZ (100 mg/kg) to 3 days old rat pups. Silymarin was administered for 15 days after the animals were confirmed diabetic (75 days after STZ injection). Blood glucose, glycosylated hemoglobin ($HbA_{1c}$), lipid peroxides (LPO) levels and reduced glutathione (GSH) contents in pancreas and liver were estimated following the established procedures. Biochemical observations were further substantiated with histological examination of pancreas. Blood glucose and $HbA_{1c}$ levels, which were elevated by STZ, were lowered to physiological levels by the administration of silymarin. The levels of LPO were significantly increased in STZ-induced diabetic rats. Silymarin reduced the LPO levels in both pancreas and liver. GSH contents which were reduced significantly in pancreas and liver of STZ-induced diabetic rats were brought back to near normal levels by silymarin treatment. Multifocal necrotic and degenerative changes of pancreas in STZ-diabetic rats were minimized to near normal morphology by administration of silymarin as evident by histopathological examination. Silymarin showed a dose dependent protective effect on STZ-induced $\beta$-cell damage. It could be attributed to the antioxidative and free radicals scavenging properties of the flavonoid. Thus, it may be considered as a natural antioxidant with potential therapeutic application in the treatment of type 2 diabetes.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.340-340
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• 1994

Since total hepatic ischemia(IS) occurs with transplantation, there has been interest in evaluating hepatic function after ischemia and subsequent reflow of blood. Four groups of animals were studied: group 1 (sham), group 2 (30mins IS), group 3 (60mins IS), and g.cup 4 (90mins IS). Serum transaminase(STA), wet weight-to-dry weight ratio(W/D), lipid peroxides(LPO), glucose-6-phosphatase(G-6-Pase) activity, Na$\^$+//K$\^$+/-ATPase(ATPase) activity were measured at 1, 5 and 24hrs after hepatic ischemia. Significant changes occurred between 1 and 5hrs of reperfusion. STA was 3579${\pm}$401, 4593${\pm}$675 and 6348${\pm}$808 U/L in group 2, 3 and 4 respectively. These changes were ischemic time-dependent manner. W/D in group 3 and 4 were significantly increased than that in sham group at all time points measured. In sham group, the level of LPO in the liver microsome remained constant at approximately 0. 5nmole MDA formed/mg protein througllout the experiment, In all ischemic groups on the other hand, the level of LPO started to increase at ischemia and markedly increased at all reperfusion period. Similar to STA, these changes were also dependent on duration of ischemia. Although G-6-Pase activity remained unchanged in both group 2 and group 3 until 5hrs of reperfusion, marked decrease in G-6-Pase activity was observed at grcup 4. ATPase activity was significantly decreased at 1, 5 and 24 hrs of reperfusion in group 3, whereas it was not changed in group 2. Furthermore, ATPase activity in group 4 started to decrease at ischemia and markedly decreased for entire reperfusion period. These data suggest that severity of hepatocellular injury is associated with period of ischemia as well as period of reperfusion.

• Environmental Analysis Health and Toxicology
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• 제14권3호
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• pp.87-93
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• 1999

Antioxidative and scavenging effects were investigated by using two hyaroxycinnamic acids (caffeetannins). such as caffeic acid and chlorogenic acid, on oxidative stress and hepatotoxicity that induced by paraquat. The results are summerized as follows: 1. To assess radical scavenging ability, reduction concentration (IC$\sub$50/) of 1.1 diphenyl-2-dipicrylhydrazine (DPPH) were measured. IC$\sub$50/ values of caffeic acid and chlorogenic acid were 29.7 ${\pm}$0.6 ${\mu}$M and 26.0${\pm}$0.5 ${\mu}$M respectively. Their radical scavenging activities showed concentration-dependent manner. 2. In H$_2$O$_2$-induced hemolysis assay to rat blood, caffeic acid and chlorogenic acid led to different effects, whose hemolysis inhibition ratios at 100 ${\mu}$M were 45.2${\pm}$7.1% and 11.6${\pm}$3.1% respectively 3. In hypoxanthine-xanthine oxidase system producing superoxide anion, caffeic acid and chlorogenic acid showed different inhibitory activities of xanthine oxidase showing 36.8${\pm}$4.3% and 5.4${\pm}$2.3% respectively. 4. To microsomal NADPH dependent cytochrome p-450 reductase in rat liver, paraquat consumed NADPH at a dose-dependent manner from 0 to 1 ${\mu}$M paraquat concentration. Caffeic acid and chlorogenic acid blocked NADPH consumption rates at concentration-dependent manner and inhibition ratios at 100 ${\mu}$M were 67.6% and 59.2% respectively. 5. Administration (30mg/kg, iv) of paraquat to rats caused the marked elevation of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and lipid peroxides (LPO) in the serum and lipid peroxides in the microsome as compared to the control group. Serum GOT, GPT, LDH, ALP and LPO and liver microsomal LPO were reduced significantly by caffeic acid (50mg/kg), chlorogenic acid (25mg/kg) and silymarin (150 mg/kg) as compared to the paraquat group. From these results, caffeic acid and chlorogenic acid exerted their antioxidative agents by removing reactive oxygen substance (ROS) and scavenging effects by inhibiting ROS generating enzyme. As a general, two hydroxyeinnamic acids showed the useful compounds for scavenger and reducer on the paraquat induced hepatotoxicity.

• 생명과학회지
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• 제11권2호
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• pp.103-110
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• 2001

This study was designed to investigate the effects of silkworm(Bombyx moril L.) powder on oxidative stress and membrane fluidity in brain membranes of rats. Sprague-Dawley(SD) male rats(160$\pm$10 g) were fed basic diet(control group), and experimental diets(SWP-200 and SWP-400 groups) added 200 and 400mg/kg BW/day for 6 weeks. There were no significant differences in cholesterol levels of brain memberanes by administration of silkworm powder (SWP). Membrane fluidities were significantly increased(21.5% and 30.8%, respectively) in brain mitochondria of SWP-200 and SWP-400 groups compared with control group, but significant difference between brain microsomes could not obtained. Basal oxygen radicals (BORs) in brain mitochondria and mircrosomes were significantly inhibited(8.5% and 16.5%, 16.8%and 24.8%, respectively) by SWP-200 and SEP-400 groups compared with control group. Induced oxygen radicals(IORs) in brain mitochondria were significantly inhibited(16.6% and 21.4%, respectively)by sWP-200 and SWP-400 groups compared with control group, but IOR in brain microsome were significantly inhibited about 16.0% by SWP-400 groups only compared with control group. Lipid peroxide(LPO) levels were significantly decreaed(14.8%and 22.4%, respectively) in brain mitochondria of SWP-200 and SWP-400 groups compared with control group, but LPO level was significantly decreased about 16.0% in brain microsome of SWP-400 group only. Oxidized protein(OP) levels were remarkably decreased(about 14.8% and 16.5%, respectively) in brain mitochondria of SWP-200 and SWP-400 groups, but OP level was significantly decreased about 13.0% in brain microsome of SWP-400 group only compared with control group, Theses results suggest that administration of in brain microsome of SWP-400 group only compared with control group. These results suggest that administration of SWP may play effective role in attenuating an oxidative stress and increasing a membrane fluidity in brain membranes.

• 생명과학회지
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• 제8권1호
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• pp.91-96
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• 1998

Pine(Pinus densiflora Sieb et Zucc.) is one of rhe popular plant drugs which has been used as a medicine in Asia. To investigate the effect of pine needle extract (PNE) on oxygen radicals and their scavenger enzymes in brain membranes of Sprague- Dawley (SD), make SD rats were fed basic diets(control group), and experimental diets (PNE group) with 0.5 and 1.0% of PNE 6 weeks. Mitochondrial hydroxyl radical levels in brain of 0.5%-PNE and 1.0%-PNE groups were significantly inhibited to 30% and 25%, respectively, and microsomal hydrogen peroxide levels in brain of 0.5%-PNE and 1.0%-PNE groups were significantly inhibited to 15% compared with control group. Cytosolic superoxide rdical levels in 1.0%-PNE group were significantly inhibited to 20% compared with control group. Lipid peroxide(LPO) levels in brain mitochondria of 0.5%-PNE and 1.0%-PNE groups were significantly lower(25% and 35%) than that in control group. Mn-superoxide disumtase (SOD) activities in brain of 0.5%-PNE and 1.0%-PNE groups were significantly higher(18% and 12%) than those in control groups, but Cu,Zn-SOD activities in brain of 0.5%-PNE were significantly activated to 15% compared with control group. Glutathione peroxidase(GSHPx) activities in brain of 1.5%-PNE and 1.0% PNE groups were significantly higher(14% and 12%) than those in control group. These results suggest that more beneficial effects such as inhibition of oxygen radicals and lipid peroxide(LPO). and oncreases of scavenger enzymes in brain membranes of SD rats may be effectively modulated by administration of pine needle extract (PNE)