UV-B 반복노출에 따른 항산화효소의 변성 및 활성저하와 RGP렌즈의 차단효과

변현영,이은정,오대환,김소라,박미정 한국안광학회 2015 한국안광학회지 Vol.20 No.2

Purpose: The present study was conducted to reveal the correlation of structural denaturation and decrease of enzyme activity when the antioxidative enzymes, superoxide dismutase (SOD) and catalase (CAT) were repeatedly exposed to UV-B, and further investigate whether the denaturation and inactivation of those enzymes can be effectively blocked by using UV-inhibitory RGP lens. Methods: Each enzyme solution was prepared from the standardized SOD and CAT, and repeatedly exposed to UV-B of 312 nm for 30 minutes, 1 hour and 2 hours a day over 1, 2, 3, 4 and 5 days. Structural denaturation of SOD and CAT induced by repeat UV-B irradiation was confirmed by the electrophoretic analysis, and their enzyme activity was determined by the colorimetric assay using the proper assay kit. At that time, the change in structure and activity of the antioxidant enzymes directly exposed to UV-B was compared to the case that UV-B was blocked by UV-inhibitory RGP lens. Results: SOD exposed repeatedly to UV-B showed the polymerization pattern in the electrophoretic analysis when it repeatedly exposed for 30 min a day, however, the change of its activity was less than 10%. On the other hand, CAT repeatedly exposed to UV-B reduced size and density of the electrophoretic band which indicated a structure denaturation, and its activity was significantly decreased. In the case that the repeat exposure time was longer, CAT activity was completely lost even though some enzyme band occurred in the electrphoretic analysis. In addition, the degeneration of CAT due to UV-B irradiation was inhibited to some extent by using RGP lens with a UV-B blocking of 63.7%, however, it was not completely inhibited. Conclusions: From these results, it was revealed that the structural denaturation of antioxidative enzymes was not perfectly correlated with the reduction in enzyme activity according to the type of enzyme. It is recommended to minimize the exposure time to UV when wearing contact lens, or wear the contact lenses having UV blocking rate of the FDA Class I blocker or the sunglasses having equivalent UV-blocking rate for reducing the damage of antioxidative enzymes induced by UV. 목적: 본 연구는 안구에 존재하는 항산화효소인 superoxide dismutase(SOD)와 catalase(CAT)가 UV-B에 반복적으로 노출되었을 때 유발되는 구조변성 및 활성저하의 상관관계를 밝히며, 자외선 차단 RGP렌즈의 사용으로 효소의 변성과활성저하가 효율적으로 차단되는가를 알아보기 위하여 수행되었다. 방법: SOD와 CAT의 표준품으로 각각의 효소용액을 제조하고 하루 30분, 1시간 및 2시간씩 312 nm의 UV-B에 1, 2, 3, 4 및 5일 동안 반복적으로 노출시켰다. 이 때 UVB에직접 노출시킨 항산화효소의 구조 및 활성변화를 자외선 차단기능이 있는 RGP렌즈로 UV-B를 차단시킨 경우와비교하였다. UV-B 반복노출에 따른 SOD와 CAT의 구조변성은 전기영동분석으로 확인하였으며, 이들 효소활성은 분석키트를 이용하여 비색분석법으로 측정하였다. 결과: UV-B에 반복노출된 SOD는 일일 30분 조사조건으로 반복노출되었을 때에도 전기영동분석에서 효소다중화(polymerization)가 관찰되었으나 활성의 변화는 10% 이내로 나타났다. 반면UV-B에 반복노출된 CAT은 전기영동 시 효소밴드크기나 진하기가 감소하여 구조변성이 나타났음을 확인할 수 있었으며, 반복노출시간이 긴 경우 CAT은 전기영동분석에서 효소밴드를 보임에도 불구하고 그 활성은 완전히 소실되었다. 또한 UV-B 조사로 인한 CAT의 변성은 63.7%의 UV-B 차단기능을 가진 RGP렌즈의 사용으로 어느 정도 억제되었으나완전히 억제되는 것은 아니었다. 결론: 이상의 결과로 UV-B 반복노출에 따른 항산화효소의 구조변성은 그 종류에 따라 효소활성의 감소정도와 반드시 일치하는 것은 아님을 알 수 있었다. 따라서 자외선으로 인한 항산화효소의 손상을막기 위하여서는 콘택트렌즈를 착용한 상태에서 자외선 노출시간을 최소화하거나, FDA Class I 차단제에 해당하는 UV 차단율을 가지는 콘택트렌즈를 착용 또는 이에 상응하는 UV차단율을 가지는 선글라스를 덧착용할 것을 권장한다.

Antioxidant Mechanism and Lipid Peroxidation Patterns in Leaves and Petals of Marigold in Response to Drought Stress

Zhiguo Tian,Fei Wang,Wene Zhang,Changming Liu,Xiuming Zhao 한국원예학회 2012 Horticulture, Environment, and Biotechnology Vol.53 No.3

In this study, malondialdehyde (MDA), relative conductivity (RC), superoxide anion (O2・-), hydrogen peroxide (H2O2), superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) as well as ascorbic acid (AsA), glutation (GSH) and carotenoid (Car) were analyzed in plants under drought condition to investigate the enzymatic and non-enzymatic antioxidant defense mechanisms of leaves and petals, respectively. Two different drought resistance marigold cultivars (Tagetes erecta L. cv. Chokdee and Tagetes erecta L. cv. Discovery)treated with 6-day drought stress were used at early flowering stage. Results indicated that drought treatment increased MDA, RC, O2・- and H2O2 contents in the two cultivars, especially in drought-sensitive cultivar ‘Discovery’. In contrast,‘Chokdee’ had higher level antioxidative enzyme activities and more non-enzymatic antioxidants than those in ‘Discovery’. SOD, POD, CAT, APX activities and non-enzymatic antioxidants (GSH and AsA) in the leaves and petals were increased at the beginning treatment, and decreased later. The activity of CAT in leaves and petals, APX in petals and AsA in petals on day 6 after treatment were lower than those in control, while Car in the two cultivars decreased consistently during drought stress treatment. In addition, all the antioxidant enzyme activities in the leaves were higher than those in petals, but AsA and GSH were accumulated at lower levels in leaves than those in petals of the both cultivars. Furthermore, significant linear relationships were found between antioxidative enzymes and reactive oxygen species (ROS), as well as in non-enzymatic antioxidants and ROS. In conclusion, drought tolerance of ‘Chokdee’ was correlated with eliminating the O2・- and H2O2 and maintaining lower lipid peroxidation as well as higher membrane stability by increasing activities of antioxidative enzymes and the amount of non-enzymatic antioxidants. Furthermore, different drought response mechanisms were involved in leaves and petals of marigold under drought stress.

The role of antioxidant enzymes in adaptive responses to environmental toxicants in vascular disease

Lee, Seung Eun,Park, Yong Seek 대한독성유전단백체학회 2013 Molecular & cellular toxicology Vol.9 No.2

Human exposure to environmental toxicants is known to contribute to the development of vascular disease. Inhalation of environmental toxicants induces inflammation and oxidative stress in the vascular system and results in tissue damage, with subsequent impairment of the vascular system. The induction of antioxidant enzyme expression is one of the most crucial components of the cellular defense against environmental insults, and represents an adaptive response. The antioxidant enzyme-mediated adaptive response has been demonstrated to attenuate toxicity caused by oxidative stress as well as inflammation. Accumulating evidence indicates that antioxidant enzymes may protect against environmental toxicants. This review highlights the role of antioxidant enzymes in the adaptive response to environmental toxicants, and explores strategies for their clinical use.

Targeting Cellular Antioxidant Enzymes for Treating Atherosclerotic Vascular Disease

Kang, Dong Hoon,Kang, Sang Won The Korean Society of Applied Pharmacology 2013 Biomolecules & Therapeutics(구 응용약물학회지) Vol.21 No.2

Atherosclerotic vascular dysfunction is a chronic inflammatory process that spreads from the fatty streak and foam cells through lesion progression. Therefore, its early diagnosis and prevention is unfeasible. Reactive oxygen species (ROS) play important roles in the pathogenesis of atherosclerotic vascular disease. Intracellular redox status is tightly regulated by oxidant and antioxidant systems. Imbalance in these systems causes oxidative or reductive stress which triggers cellular damage or aberrant signaling, and leads to dysregulation. Paradoxically, large clinical trials have shown that non-specific ROS scavenging by antioxidant vitamins is ineffective or sometimes harmful. ROS production can be locally regulated by cellular antioxidant enzymes, such as superoxide dismutases, catalase, glutathione peroxidases and peroxiredoxins. Therapeutic approach targeting these antioxidant enzymes might prove beneficial for prevention of ROS-related atherosclerotic vascular disease. Conversely, the development of specific antioxidant enzyme-mimetics could contribute to the clinical effectiveness.

Understanding cross-tolerance mechanism and effect of drought priming on individual heat stress and combinatorial heat and drought stress in chickpea

Yadav Renu,Juneja Sumandeep,Kumar Rashpal,Saini Rashmi,Kumar Sanjeev 한국작물학회 2022 Journal of crop science and biotechnology Vol.25 No.5

In northern India, chickpea experiences abrupt heat and drought stress during the late developmental stage and entails significant production loss. In the present study, the effect of heat stress and combined stress (heat and drought) was assessed in five varieties of chickpea along with the underlying mechanism of cross-tolerance by priming. Healthy seedlings (24 days old) were primed with mild drought stress and exposed to three different temperatures, i.e., 38 °C, 35 °C, and 32 °C for 12, 24, and 36 h respectively, and also in combination with drought. The damage and tolerance were evaluated based on biochemical and physiological indicators. Results indicate that significant response was observed at 35 °C as compared to 32 and 38 °C in terms of decrease in leaf water content, increased electrolyte leakage and lipid peroxidation, decreased chlorophyll content, increased accumulation of proline and total sugars, and increased antioxidative activity of superoxide dismutase, catalase, guaiacol peroxidase, ascorbate peroxidase, and glutathione reductase. The consequence of combined stress was more distinct than the individual heat stress and cannot be extrapolated from the synergistic effect of the two stresses. In addition, priming induced cross-tolerance at 35 °C by improving the membrane damage, photorespiration, photosynthetic pigment, osmolyte accumulation, and some antioxidative enzymes. On the basis of all the above parameters, PDG4 was identified as the best performing variety and tolerant to heat stress while GPF2 was the worst performing and sensitive to heat stress. It can be inferred that both severity and duration of stress are important and priming can be considered as an important tool to induce cross-tolerance in crop plants.

운동으로 유발된 산화 스트레스와 마늘의 항산화 작용

윤군애(Yoon Gun-Ae) 韓國營養學會 2007 Journal of Nutrition and Health Vol.40 No.8

This study was to investigate lipid peroxidation, antioxidant enzyme activity and DNA damage after exercise, and the protective effect of garlic against exercise-induced oxidative stress. Male Sprague-Dawley rats (4 weeks old) were randomly divided into three groups of 6 rats each; control group (Con) without garlic and exercise, Ex group with exercise alone, and Ex-G group with 2% garlic and exercise. For 4 weeks, rats were given diets containing 15% corn oil and 1% cholesterol with or without garlic. The swimming was selected as a model for exercise performance. Rats swam for 40 min a day, for 5 days a week. Group Ex and Ex-G showed significant lowering in body weight gain and fat accumulation compared to control. No significant changes were observed in levels of plasma cholesterol and triglyceride among three groups, demonstrating that exercise and garlic had no effects on changes of blood lipid. This finding of blood lipid seems to be due to higher plant sterol content in com oil. The DNA tail moment of lymphocytes showed greater tendency in Ex and Ex-G than in control, but garlic supplements failed to suppress DNA damages. Compared to control, Ex had higher plasma TBARS which was lowered to the control's level in Ex-G with 2% garlic supplementation (p<0.05). Ex-G led to a higher hepatic superoxide dismutase (SOD) activity than control and Ex (p<0.05). Activity of hepatic catalase was also increased in Ex-G, while in Ex it was significantly low (p<0.05). It seemed that TBARS levels were related to the activities of SOD and catalase, and that garlic contributed to increasing the enzyme activities and led to decrease of TBARS. These results demonstrate that lipid peroxidation and DNA damage occur as a consequences of oxidative stress after exercise, and that antioxidant defense against oxidative stress could be enhanced by garlic supplementation through the induction of antioxidant enzymes. However, further investigations should be done on the garlic effect on DNA damage.

Protective effects of unsaponifiable matter from rice bran on oxidative damage by modulating antioxidant enzyme activities in HepG2 cells

Ham, Hyeonmi,Yoon, Sung Won,Kim, In-Hwan,Kwak, Jieun,Lee, Jeom-Sig,Jeong, Heon-sang,Lee, Junsoo Elsevier 2015 FOOD SCIENCE AND TECHNOLOGY -ZURICH- Vol.61 No.2

<P><B>Abstract</B></P> <P>Rice bran is a byproduct of the rice milling process. It contains high levels of bioactive phytochemicals such as phytosterols, tocopherols, tocotrienols, γ-oryzanol, triterpene alcohol, and other minor compounds, which have antioxidant and health-promoting properties. The objective of this study was to evaluate the?protective effect of unsaponifiable matter (USM) from rice bran against oxidative damages induced by <I>tert</I>-butyl hydroperoxide (TBHP) in HepG2 cells. Levels of cellular reactive oxygen species (ROS), cellular lipid peroxidation, reduced glutathione (GSH), and antioxidant enzyme activity were evaluated as biomarkers of the cellular oxidative status. HepG2 cells were pretreated with various concentrations of USM (0–100?μg/mL) for 12?h prior to TBHP exposure. Pretreatment of HepG2 cells with USM prevented the cell damage induced by TBHP in a dose-dependent manner. Cellular generation of ROS, formation of malondialdehyde (MDA), and depletion of GSH induced by TBHP were prevented by pretreatment with USM. In addition, treatment with TBHP increased the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. However, pretreatment with USM significantly reduced the activities of these enzymes. These results indicate that treatment of HepG2 cells with USM confers significant protection against oxidative damage by modulating ROS production, GSH levels, and antioxidant enzyme activity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Unsaponifiable matter (USM) was prepared from rice bran. </LI> <LI> USM prevented the cell damage in a dose-dependent manner. </LI> <LI> Oxidative changes induced by oxidative stress were prevented by USM. </LI> <LI> USM significantly modulated antioxidant enzyme activities of HepG2 cells. </LI> </UL> </P>

Effect of 2,4,5-Trichlorobiphenyl (PCB-29) on Oxidative Stress and Activities of Antioxidant Enzymes in Tomato Seedlings

Cho, Un-Haing,Sohn, Ji-Young The Ecological Society of Korea 2002 Journal of Ecology and Environment Vol.25 No.6

Leaves of two-week old seedlings of tomato (Lycopersicon esculentum) were treated with various concentrations (0, 0.2 and 0.4 $\mu$g/1) of 2,4,5-trichlorobiphenyl (PCB-29) and subsequent growth of seedlings, symptoms of oxidative stress and activities of antioxidant enzymes were investigated. Compared with the non-treated control, foliar application of PCB-29 decreased both biomass and superoxide ($O_2$) radical production but increased hydrogen peroxide production and lipid peroxidation such as malondialdehyde (MDA) formation with increased activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (GPX). Further studies on the isozymes of SOD, peroxidase (POD) and APX showed that all three isozymes of SOD such as Mn-SOD, Fe-SOD and Cu/Zn-SOD, two among four isozymes of POD and all three isozymes of APX were selectively increased in response to PCB. Therefore, we suggest that a possible cause for the reduction of seedling growth by PCB exposure is the oxidative stress including over production of hydrogen peroxide and the selective expression of specific isozymes of some antioxidant enzymes.

Changes in Antioxidant Enzyme Activities of Two Contrasting Ecotypes of Arundinella hirta to Drought Stress

민창우,Yun-Hee Kim,이병현 한국초지조사료학회 2023 한국초지조사료학회지 Vol.43 No.2

To understand antioxidant enzyme response of two contrasting Arundinella hirta ecotypes to drought stress, drought-tolerant Youngduk and drought-sensitive Jinju-1, were comparatively analyzed changes in the enzymatic activities of peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GR). Two ecotypes, drought-tolerant Youngduk and drought-sensitive Jinju-1 were subjected to drought stress by withholding water for 12 days. ROS accumulation level and electrolytic leakage were significantly increased in both A. hirta ecotypes by drought stress treatment but less in Youngduk than Jinju-1. The RWC significantly decreased in both the drought stress-treated ecotypes as compared to control, but less in Youngduk than Jinju-1. Soluble sugar and protein content were increased more in drought stress-treated Youngduk as compared to Jinju-1. The activities of antioxidant enzymes such as SOD, CAT, POD, APX, and GR increased significantly in both the drought stress-treated ecotypes Youngduk and Jinju-1 as compared to control. The increase in antioxidant enzyme activity level was more prominent in drought stress-treated Youngduk as compared to Jinju-1. Taken together, these results suggest that Youngduk was more tolerant to drought stress than Jinju-1, and seem to indicate that tolerance of A. hirta to drought stress is associated with increased activity of antioxidant enzymes.

Antioxidant Enzyme-Enhancing Effects of Jeju Water Containing Vanadium in vivo

김아름다슬,강경아,Rui Zhang,Mei Jing Piao,Suhkmann Kim,지영흔,이남호,Ho Jin You,고경수,현진원 대한암예방학회 2011 Journal of cancer prevention Vol.16 No.1

Recently, we reported that Jeju water containing vanadium (S3, 26.0±2.0 μg/l) exhibits an antioxidant effect via the scavenging of reactive oxygen species and by enhancing of antioxidant enzyme activities in vitro. In the present study, we examined the antioxidant effect of S3 with regard to antioxidant enzymes in vivo. C57BL/6 mice were given tap water or S3 for 90 days, and then the liver tissues were analyzed. Compared to tap water, S3 enhanced the activities of superoxide dismutase, catalase, glutathione peroxidase, and heme oxygenase-1. S3 also enhanced the level of reduced glutathione, which was determined by high-resolution magic angle spinning nuclear magnetic resonance spectroscopy and by a colorimetric assay. These results suggested that vanadium-containing Jeju water has antioxidant effects via enhancing antioxidant enzyme activities in vivo. (Cancer Prev Res 16, 58-64, 2011)