Electroconvulsive Shock이 마우스 뇌조직 Superoxide Dismutase의 활성에 미치는 영향

권년수,이희성,Kwon, Nyoun-Soo,Lee, Hi-Sung 생화학분자생물학회 1984 한국생화학회지 Vol.17 No.3

In the present study, prolonged effects of the serial electroconvulsive shocks on the activity of superoxide dismutase (superoxide: superoxide oxidoreductase, EC 1.15.1.1): both cyanide-sensitive cytosolic enzyme and cyanide-resistant mitochondrial enzyme, were observed in the mouse brain. The rate constants for synthesis and degradation of these enzymes were determined. In addition, the changes in the superoxide radical production, the amount of hydrogen peroxide and the activity of superoxide dismutase were observed in the mouse brain which received single electroconvulsive shock. The results were summarized as follows: 1. Homogenates prepared from the brains of mice treated with single electroconvulsive shock showed considerably higher superoxide radical production when compared with those of the control mice. 2. By single electroconvulsive shock the generation of hydrogen peroxide increased at 1 minute after the electric stimulus; while the activity of superoxide dismutase increased at the time when tonic convulsion occurred. 3. By the serial electroconvulsive shocks the activity of cytosolic superoxide dismutase increased to approximately 1.6 times its control value ($Kd=3.60{\times}10^{-2}/hr$; Ks=6.01 units/hr/g tissue; $t_{1/2}=19\;hrs$); and the mitochondrial enzyme increased to approximately 2 times its control value ($Kd=1.53{\times}10^{-2}/hr$; Ks=1.44 units/hr/g tissue; $t_{1/2}=45\;hrs$). 4. The rate constants at recovery period were: $Kd=1.91{\times}10^{-2}/hr$; Ks=2.01 units/hr/g tissue; $t_{1/2}=36\;hrs$ for the cytosolic superoxide dismutase and $Kd=3.08{\times}10^{-2}/hr$; Ks=1.42 units/hr/g tissue; $t_{1/2}=23\;hrs$ for the mit ochondrial enzyme. ICR순계 마우스에 electroconvulsive shock(ECS)을 가해 뇌조직에서 superoxide radical의 생성, $H_2O_2$의 양, superoxid edismutase(superoxide: superoxide oxidoreductase, EC 1.15.1.1)의 활성에 미치는 영향 등을 관찰하고, 주기적으로 반복하여 ECS를 가함으로써 superoxide dismutase(SOD)를 유발시켜 합성 및 분해속도상수를 구한 결과 다음과 같은 결론을 얻었다. 1. ECS를 받은 마우스의 뇌조직 균질액에서 superoxide radical의 생성이 대조군에 비해 유의한 차이가 있게 증가되었다(p<0.01). 2. ECS에 의해 마우스 뇌조직의 SOD 활성도는 긴장성 경련기에, $H_2O_2$의 양은 1분후에 가장 높은 증가를 나타내었으며 SOD 활성도와 $H_2O_2$양의 변화 양상은 비슷하였다. 3. 일련의 ECS로 세포질 SOD는 대조군의 약 1.6배로 전기자극 후 11일에 가장 높은 활성을 나타냈다($Kd=3.60{\times}10^{-2}/hr$; Ks=6.01 units/hr/g tissue; $t_{1/2}=19\;hrs$). Mitochondria의 SOD는 전기자극후 11일에 대조군의 약 2배로 가장 높은 활성을 나타내었다($Kd=1.53{\times}10^{-2}/hr$; Ks=1.44 units/hr/g tissue; $t_{1/2}=45\;hrs$). 4. 회복기에 세포질 효소의 속도상수는 Kd가 $1.91{\times}10^{-2}/hr$, Ks가 2.01 units/hr/g tissue, 반감기는 36시간이었으며, mitochondria 효소의 Kd는 $3.08{\times}10^{-2}/hr$, Ks는 1.42 units/hr/g tissue, 반감기는 23시간이었다.

Electroconvulsive Shock 이 마우스 뇌조직 Superoxide Dismutase 의 활성에 미치는 영향

권년수,이희성 ( Nyoun Soo Kwon,Hi Sung Lee ) 생화학분자생물학회 1984 BMB Reports Vol.17 No.3

In the present study, prolonged effects of the serial electroconvulsive shocks on the activity of superoxide dismutase (superoxide: superoxide oxidoreductase, EC 1.15.1.1) : both cyanide-sensitive cytosolic enzyme and cyanide-resistant mitochondria) enzyme, were observed in the mouse brain. The rate constants for synthesis and degradation of these enzymes were determined. In addition, the changes in the superoxide radical production, the amount of hydrogen peroxide and the activity of superoxide dismutase were observed in the mouse brain which received single electroconvulsive shock. The results were summarized as follows: 1. Homogenates prepared from the brains of mice treated with single electroconvulsive shock showed considerably higher superoxide radical production when compared with those of the control mice. 2. By single electroconvulsive shock the generation of hydrogen peroxide increased at 1 minute after the electric stimulus; while the activity of superoxide dismutase increased at the time when tonic convulsion occurred. 3. By the serial electroconvulsive shocks the activity of cytosolic superoxide dismutase increased to approximately 1.6 times its control value (Kd=3.60×10^(-2)/hr; Ks=6.01 units/hr/g tissue ; t_½=19 hrs) ; and the mitochondriaI enzyme increased to approximately 2 times its control value (Kd=1.53×10^(-2)/hr; Ks=I.44 units/hr/g tissue; t_½=45 hrs). 4. The rate constants at recovery period were: Kd=1.91×10^(-2)/hr;Ks=2.01 units/hr/g tissue; t_½=36 hrs for the cytosolic superoxide dismutase and Kd =3.08×10^(-2)/hr; Ks=1.42 units/hr/g tissue; t_½=23 hrs for the mit ochondrial enzyme.

Azid 에 의한 Mouse 폐내 산소독성의 증강

백광진,권년수,이희성 ( Kwang Jin Baek,Nyoun Soo Kwon,Hee Sung Lee ) 생화학분자생물학회 1992 BMB Reports Vol.25 No.2

An increased production of reactive oxygen species has been postulated to be a major factor in the pathogenesis of lung damage during hyperoxia. Azide is an inhibitor of superoxide dismutase (SOD) and catalase. These enzymes are important in defence mechanism against oxygen toxicity by removing superoxide radicals and hydrogen peroxide. Therefore, azide treatment could enhance oxygen toxicity. Mice were exposed to 100% O₂ (1 atm) with or without pretreatment with azide (8.1 ㎎/㎏ body weight). Biochemical indicators of oxygen toxicity in the lung of mouse were measured. Production of superoxide radicals and hydroxyl radicals increased in the lung of mouse treated with azide and 100% O₂. Superoxide radical generation was maximized at 24 h after the treatment, while the highest hydroxyl radical production occurred at 48 h. Xanthine oxidase activity was continuously decreased by the treatment with azide and 100% O₂. During the first 6 h of the treatment ∼90% of xanthine oxidase activity appeared as the type $quot;O$quot;. The Mn-SOD and glutathione peroxidase in azide and 100% O₂ treated group showed a significantly higher activity than those in the azide or 100% O₂ treated groups, while catalase activity was significantly lower in the azide/O₂-treated group. Survival time in azide and 100% O₂exposed group was significantly shorter than that in the azide or 100% O₂ treated groups. When SOD-containing liposomes (1,500 units/mouse) were introduced into the peritoneal cavity, the survival time was significantly extended. These results suggested that oxygen toxicity occurred in the lung of 100% O₂ exposed mouse by overproduction of reactive oxygen species and that the toxicity was exacerbated by azide-induced inhibition of enzymes in capable of removing reactive oxygen species. Liposomal SOD protected the mouse from the oxygen toxicity and extended the survival time.

사람 태반의 Superoxide Dismutase의 정제 및 성상

문진수,권년수,이근배,이희성 중앙대학교 의과대학 의과학연구소 1982 中央醫大誌 Vol.7 No.2

The distribution and some properties of superoxide dismutase of human term placenta have been studied. Human placenta was fractionated by differential centrifugation into mitochondrial and cytosolic fractions. The activity of superoxide dismutase was measures by the methodof McCord and Fridovich. Cytosolic superoxide dismutase was purified by ammonium sulfate precipitation, treatment with a chloroform-ethanol mixture, and DEAE-cellulose column chromatography. The results are summarized as follows; 1. Human term placenta contains two types of superoxide dismutase, one of which is localized in the mitochondria while the other is found in the cytosol. The mitochondrial superoxide dismutase was inactivated by treatment with a moxture of chloroform and ethanol whereas the cytosolic superoxide dismutase was not. 2. The activity of cytosolic and mitochondrial superoxide dismutase was found to be 7.44 units and 1.27 units per g of wet tissue, repectively. 3. The molecular weight of cytosolic superoxide dismutase was estimated to be about 33,000 by gel filtration. 4. The ultraviolet absorption spectrum of cytosolic enzyme indicates the lack of tryptophan. The spectrum of the enzyme in the uitraviolet region was similar to that of phenylalanine. 5. Purified cytosolic superoxide dismutase contains 2Cu^2+ and 2Zn^2+ per molecule. This enzyme was found to be similar to the other cupro-zinc superoxide dismutase which have been isolated from diverse eukaryotes. 6. Cyanide at 0.5 mM and 5.0 mM inhibits the activity of cytosolic superoxide dismutase 31% and 98%, respectively, but mitochondrial superoxide dismutase was not inhibited by this compound.

허혈-재관류에 의한 흰쥐 간의 손상에 있어서 반응성 산소종의 역할

지경천,권년수,이희성,김상준,장선택 중앙대학교 의과대학 의과학연구소 1992 中央醫大誌 Vol.17 No.4

Increased generation of reactive oxygen species is thought to be a major cause of tissue in ischemia-reperfusion injury. Left and median lobes of rat livers were subjected to 20 minutes of ischemia followed by reperfusion for up to 120 minutes. Superoxide radical generation was enhanced to 338 μmol/minute/g tissue after 60 minutes of reperfusion,and 367 μmol/minute/g tissue after 120 minutes. Superoxide generation in the liver of the control animal was 260 μmol/minute/g tissue. The activity of xanthine oxidase, a superoxide radical-generating enzyme, was also elevated in the liver treated with ischemia-referfusion. These results indicate that xanthine oxidase-catalyzed reaction is an important source for the superoxide generation in rat liver treated with ischmia-referfusion. The activities of superoxide dismutase and catalase, enzyme responsible in removing superoxide radical and hydrogen peroxide, were measured. Cu, Zn-superoxide dismutase activity was significantly higher in reperfused liver after ischemia than in control. However, the activity of Mn-containing superoxide dismutase was significantly low in reperfusion. The extent of tissue damage by ischemia-reperfusion was evaluated by measuring lipid peroxidation. Thiobarbituric acid reactive substance was significantly elevated in the liver treated with 60 minutes of ischemia followed by 60 minute of reperfusion. These results suggested that increased reactive oxygen species and diminished activities of enzyme removing toxic oxygen species rendered the damages on the liver which was sujected to ischemia followed by reperfusion.

Copper(II)에 의한 Xanthine Oxidase의 활성 억제

백선흠,한기정,이희성,권년수 중앙대학교 의과대학 의과학연구소 1993 中央醫大誌 Vol.18 No.3

Xanthine oxidase (XO) plays important roles in the tissue damge during ischemia-reperfusion by generating superoxide radicals, a reactive oxygen species. The present study examined effects of cooper(Ⅱ), a transition metal ion, on XO activity. Cuso^4 at the concentration of 0.5㎛ inactivated 22% of XO. The inactivation was augmented by increasing concentration of copper(Ⅱ) or incubation time. Among other tranistion metal ions tested,Hg(Ⅱ) was most effective; Others including Cu(Ⅰ), Fe(Ⅱ), and Fe(Ⅲ) were not as effective as Cu(Ⅱ), EDTA (50㎛) almost completely abolished she inactivation of XO by 5 ㎛ copper (Ⅱ). Protections by other copper chelator, such as sodium citrate and L-His were incomplete. The cooper (Ⅱ)-induced XO inactivation was not enhanced by the presence of hydrogen peroxide, and was not protected by varoious oxygen radical scavengers.

면역복합체에 의한 신 손상에 있어서 Nitric Oxide 발생의 역할

고창현,정상인,유재형,이희성,권년수 중앙대학교 의과대학 의과학연구소 1994 中央醫大誌 Vol.19 No.2

Uncontrolled excessive immune reaction may cause tissue damage and destruction by acute or chronic inflammations. Reactive oxygen species generated from active neutrophils and macrophages are known as principal causative factors in inflammatory tissue damage. In the present study, role of nitric oxide generation in tissue injury was examined in immune complex-mediated experimental glomerulonephritis. When concanavalin A and its antiserum were injected into rat, urinary protein excretion during 24h was increased as a parameter of function impairment. Excretion of nitrite and nitrate, stable oxidation products of nitric oxide, were elevated by the administration of immune complex indicating induction of nitric oxide synthase. Protein excretion in 24h urine was diminished along with decreased nitrite/nitrate generation by addition of N-methyl-L-arginine, a competitive inhibitor of nitric oxide synthase. This protective effect of N-methyl-L-arginine was abolished by excess L-arginine not by D-arginine. Concentrations of lipid hydroperoxide, an intermediate substance in lipid peroxidation, in renal tissue were increased by elevated nitric oxide synthase activitiy (indicatd by high nitrite/nitrate excretion) and decreased by depressed nitric oxide synthase activity. These results suggested that nitric oxide could play an role in tissue damage in immune complex-mediated inflammations.

허혈-재관류시킨 흰쥐 비복근 내의 Catalase, Glutathione Peroxidase 및 Superoxide Dismutase의 활성도

최창영,백광진,이성행,권년수,이희성 중앙대학교 의과대학 의과학연구소 1993 中央醫大誌 Vol.18 No.3

Increased generation of reactive oxygen species is thought to be a major caus of tissue damage in schemia-reperfusion injury. This study was designed to examine the activities of scavangers of oxygen free radicals, namely, superoxide dismutase (SOD), catalase, and glutathione (GSH) peroxidase, when revascularization was performed after a long period of ischemic time in 20 surgically amputated rat limbs. The results were as followss: 1. In the experimental group treated with ischemia or ischemia-reperfusion, activities of catalase were about 2 times higher than those in control group, and the activities in the rats administered with SOD after ischemia were about 6 times higher than those in controls. 2. Activities of GSH peroxidase in the experimental groups treated with ischemia were increased significantly, while GSH peroxidase activities in ischemia-reperfusion group were similar to that in controls. SOD-administered group showed higher GSH peroxidase activity than control 3. Activities of SOD was decreased in the experimental groups treated with ischemia or ischemia-reperfusion.

Gα^(h)-단백질에 의해 활성화되는 Phospholipase C 이소효소의 확인

조강호,박권식,채규영,한기정,김형석,김형일,윤혜영,권년수,이희성,백광진 중앙대학교 의과대학 의과학연구소 2000 中央醫大誌 Vol.25 No.4

마우스 각종 장기의 Xanthine Dehydrogenase-Xanthine Oxidase 활성도에 미치는 산소 농도의 영향

장승훈,한기정,권년수,이희성 중앙대학교 의과대학 의과학연구소 1993 中央醫大誌 Vol.18 No.2

Xanthine oxidase (XO) derved from xanthine dehydrogenase (XD) during ischemia plays important roles in tissue damage by generating superoxide radicals. In the present study, we examined in vivo regulations of XD-XO activities of various organs by environmental oxygen tension. Mice were exposed to 100% oxygen for 3, 10, or 30 h, or 7% oxygen (73% nitrogen) for 4h. XD-XO activities of liver, kidney, lung and brain were measured. The enzyme activities in both liver and kidney were markedly increased by the treatment with 100% oxygen. In the liver the enhanced activity was sustained until 30 h, while the elevated renal activity was found only in the mouse treated for 10 h. XD-XO activities were decreased in lung and brain by the treatment with 100% oxygen. When mice were exposed to 7% oxygen, XD-XO activity was markedly decreased in lung and brain, while the activites in liver and kidney were not significantly changed. These results indicate that XD-XO can be regulated by the environmental oxygen tension, and the regulation is organ-specific.