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.

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.

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.

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>

Myricetin과 Taruine의 병용 투여가 B16F10 세포의 항산화 효소계에 미치는 영향

유지선(Ji Sun Yu),김안근(An Keun Kim) 대한약학회 2006 약학회지 Vol.50 No.1

The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress damage. To determine whether myricetin or myricetin/taurine can exert antioxidative effects not only by modulating the AOE system directly but also by scavenging free radical, we investigated the influence of the myricetin and taurine on cell viability, ROS level, activities of different antioxidant enzyme, and the expression of different antioxidant enzyme. As results, the cell viability showed inhibition of the proliferation with treatment of 'myricetin' or 'myricetin with taruin', respectively, with does-dependent manner. Compared to control, the treatment of 'myricetin' decreased activities and gene expressions of superoxide dismutase (SOD), and glutathione peroxidase (GPx). However, combined treatment of 'myricetin with taurine' increased activities and gene expressions of the SOD, GPx, and catalase (CAT). In addition, the combined treatment of 'myricetin with taurine' somewhat decreased ROS levels, compared to the treatment of 'myricetin'. In conclusion, our study provides that the combined treatment of different antioxidants can enhance antioxidant effects.

Antioxidant and ACE Inhibitory Activities of Soybean Hydrolysates: Effect of Enzyme and Degree of Hydrolysis

Ji-Soo Lee,Mi Ae Yoo,Seung Hyun Koo,Hyung-Hee Baek,Hyeon Gyu Lee 한국식품과학회 2008 Food Science and Biotechnology Vol.17 No.4

Native soy protein isolate (SPI) was hydrolyzed with 4 different proteolytic enzymes, including bromelain, papain, Neutrase, and Flavourzyme. SPI hydrolysates with the degree of hydrolysis (DH) in range of 6 to 15% were prepared by each enzyme. The angiotensin I converting enzyme (ACE) inhibitory and the antioxidant activities of the SPI hydrolysates, such as superoxide dismutase-like activity and inhibition of the linoleic acid autoxidation, were evaluated. Overall, as the DH increased, all evaluated bioactivities of the SPI hydrolysates significantly increased. The significantly highest ACE inhibitory and antioxidant activities were found in hydrolysates made with papain and bromelain, respectively. SPI hydrolysates by Flavourzyme showed the significantly lowest activity in all tested bioactivities. The results suggested that ACE inhibitory and antioxidant activities of SPI hydrolysates were determined by the DH and by the enzyme used.

Antioxidant mechanism of isoflavone metabolites in hydrogen peroxide‐stimulated rat primary astrocytes: critical role of hemeoxygenase‐1 and NQO1 expression

Park, Jin‐,Sun,Jung, Ji‐,Sun,Jeong, Yeon‐,Hui,Hyun, Jin‐,Won,Le, Thi Kim Van,Kim, Dong‐,Hyun,Choi, Eung‐,Chil,Kim, Hee‐,Sun Blackwell Publishing Ltd 2011 Journal of Neurochemistry Vol.119 No.5

<P><I>J. Neurochem.</I> (2011) <B>119</B>, 909–919.</P><P><B>Abstract</B></P><P>The brain is highly vulnerable to oxidative stress, thus controlling oxidative stress is considered to be an important therapeutic target for neurodegenerative diseases. In this study, we found that two isoflavone metabolites (tectorigenin and glycitein) inhibited hydrogen peroxide‐induced reactive oxygen species (ROS) generation and subsequent cell death in rat primary astrocytes. The isoflavone metabolites increased the expression of phase II antioxidant enzymes, such as hemeoxygenase‐1 (HO‐1) and NAD(P)H:quinone oxidoreductase 1 (NQO1), and pre‐treatment of cells with their specific inhibitors or small interfering RNA (siRNA) reversed the antioxidant and cytoprotective effects of isoflavones. The results suggest that the antioxidant/cytoprotective effects of isoflavone metabolites are at least because of increased HO‐1 and NQO1 expression. Further mechanistic studies revealed that isoflavones increase the binding of transcription factors [nuclear factor‐E2‐related factor 2 (Nrf2) and c‐Jun] to the antioxidant response element (ARE) on HO‐1 and NQO1 promoters. Down‐regulation of Nrf2 and/or c‐Jun using dominant‐negative mutants (DNMs) or siRNA diminished the expression of HO‐1 and NQO1, suggesting that Nrf2 and c‐Jun are key transcription factors modulating HO‐1/NQO1 expression. Moreover, PI3 kinase and mitogen‐activated protein kinase (MAPK) signaling pathways were shown to be involved in HO‐1 and/or NQO1 expression by isoflavones. Our data collectively suggest that HO‐1 and NQO1 play a critical role in antioxidant effects of isoflavone metabolites in rat brain astrocytes.</P>

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.

Antioxidant action of soy isoflavones on oxidative stress and antioxidant enzyme activities in exercised rats

Gun-Ae Yoon,Sunmin Park 한국영양학회 2014 Nutrition Research and Practice Vol.8 No.6

BACKGROUND/OBJECTIVES: Isoflavones are widely believed to be beneficial to human health, in relation to their antioxidant potentials. Exercise can cause an imbalance between reactive oxygen species (ROS) and antioxidants. This study was conducted in order to investigate the ability of isoflavones in amelioration of oxidative stress induced by exercise. MATERIALS/METHODS: Male Sprague-Dawley rats were assigned to one of four groups: isoflavone-free with no exercise (CON-sd), isoflavone-free with exercise (CON-ex), isoflavone-supplemented with no exercise (ISF-sd), and isoflavone-supplemented with exercise (ISF-ex). Animals exercised on the treadmill for 30 minutes per day, five days per week. TBARS as a marker of oxidative stress and antioxidant enzyme activity, including SOD, GSH-px, and catalase were determined in liver tissue. Serum lipid profile was also examined. RESULTS: A significant effect of isoflavone alone was observed on abdominal fat pad mass. ISF-ex had significantly less abdominal fat pad than CON-ex. Both exercise and isoflavone treatment had significant effects on lowering plasma triglyceride (TG), thus, the ISF-ex group had a significantly lower TG level than the CON-sd group, by 30.9%. However, no differences were observed in plasma cholesterol, HDL-C, and cholesterol/HDL-C ratio. Exercise, isoflavone, and exercise-isoflavone interaction effects were significant on thiobarbituric acid reactive substances (TBARS) (P = 0.001, 0.002, and 0.005, respectively). The CON-ex group showed a higher TBARS level than the other three groups. By contrast, in the ISF-ex group, TBARS was restored to the level of the ISF-sd or CON-sd group. Isoflavone had a significant effect on superoxide dismutase (SOD) (P = 0.022) and catalase activities (P = 0.049). Significantly higher SOD and catalase activities were observed in ISF-ex than CON-ex. SOD and catalase activities showed an inverse pattern of TBARS. Taken together, isoflavones increased the activities of SOD and catalase with concomitant decreases in TBARS, indicative of decreased oxidative stress. CONCLUSIONS: Isoflavone supplementation enhances antioxidant action with attenuation of exercise-induced oxidative stress, as measured by decreases in TBARS, and inhibits body fat accumulation and plasma TG increase. Antioxidative effects ascribed to isoflavones may be partially exerted via enhancement of antioxidant enzyme activities.

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.