Advances in the research on the AsA-GSH cycle in horticultural crops

Li, Yingli; Liu, Yufang; Zhang, Jianguang

doi:10.1007/s11703-009-0089-8

Cited by 69 publications

(51 citation statements)

References 46 publications

(38 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Non-enzymatic antioxidants include carotenoids, ascorbate (AsA), glutathione (GSH), flavanones, and anthocyanins [12,13]. The AsA-GSH cycle, an important antioxidant system, can maintain an appropriate oxidative and reductive environment in plants under stress [14]. GPX is another important ROS-scavenging enzyme that uses GSH to reduce H 2 O 2 as well as organic and lipid hydroperoxides.…”

Section: Introductionmentioning

confidence: 99%

Selenium Pretreatment Upregulates the Antioxidant Defense and Methylglyoxal Detoxification System and Confers Enhanced Tolerance to Drought Stress in Rapeseed Seedlings

Hasanuzzaman

Fujita

2011

Biol Trace Elem Res

325

155

View full text Add to dashboard Cite

In order to observe the possible regulatory role of selenium (Se) in relation to the changes in ascorbate (AsA) glutathione (GSH) levels and to the activities of antioxidant and glyoxalase pathway enzymes, rapeseed (Brassica napus) seedlings were grown in Petri dishes. A set of 10-day-old seedlings was pretreated with 25 μM Se (Sodium selenate) for 48 h. Two levels of drought stress (10% and 20% PEG) were imposed separately as well as on Se-pretreated seedlings, which were grown for another 48 h. Drought stress, at any level, caused a significant increase in GSH and glutathione disulfide (GSSG) content; however, the AsA content increased only under mild stress. The activity of ascorbate peroxidase (APX) was not affected by drought stress. The monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR) activity increased only under mild stress (10% PEG). The activity of dehydroascorbate reductase (DHAR), glutathione S-transferase (GST), glutathione peroxidase (GPX), and glyoxalase I (Gly I) activity significantly increased under any level of drought stress, while catalase (CAT) and glyoxalase II (Gly II) activity decreased. A sharp increase in hydrogen peroxide (H(2)O(2)) and lipid peroxidation (MDA content) was induced by drought stress. On the other hand, Se-pretreated seedlings exposed to drought stress showed a rise in AsA and GSH content, maintained a high GSH/GSSG ratio, and evidenced increased activities of APX, DHAR, MDHAR, GR, GST, GPX, CAT, Gly I, and Gly II as compared with the drought-stressed plants without Se. These seedlings showed a concomitant decrease in GSSG content, H(2)O(2), and the level of lipid peroxidation. The results indicate that the exogenous application of Se increased the tolerance of the plants to drought-induced oxidative damage by enhancing their antioxidant defense and methylglyoxal detoxification systems.

show abstract

Section: Introductionmentioning

confidence: 99%

Selenium Pretreatment Upregulates the Antioxidant Defense and Methylglyoxal Detoxification System and Confers Enhanced Tolerance to Drought Stress in Rapeseed Seedlings

Hasanuzzaman

Fujita

2011

Biol Trace Elem Res

325

155

View full text Add to dashboard Cite

show abstract

“…Recently, the overexpression of a DHAR gene has been shown to increase AsA levels and enhance cold tolerance in tobacco (Le Martret et al, 2011). However, studies of this kind have been limited thus far in horticultural crops (Li et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

Exogenous abscisic acid increases antioxidant enzymes and related gene expression in pepper (Capsicum annuum) leaves subjected to chilling stress

Guo¹,

Chen²,

Gong³

et al. 2012

Genet. Mol. Res.

113

View full text Add to dashboard Cite

ABSTRACT. To elucidate how physiological and biochemical mechanisms of chilling stress are regulated by abscisic acid (ABA) pretreatment, pepper variety (cv. 'P70') seedlings were pretreated with 0.57 mM ABA for 72 h and then subjected to chilling stress at 10°/6°C (day/night). Chilling stress caused severe necrotic lesions on the leaves and increased malondialdehyde and H 2 O 2 levels. Activities of monodehydroascorbate reductase (DHAR), dehydroascorbate reductase, glutathione reductase, guaiacol peroxidase, ascorbate peroxidase, ascorbate, and glutathione increased due to chilling stress during the 72 h, while superoxide dismutase and catalase activities decreased during 24 h, suggesting that chilling stress activates the AsA-GSH cycle under catalase deactivation in pepper leaves. ABA pretreatment induced significant increases in the above-mentioned enzyme activities and progressive decreases in ascorbate and glutathione levels. On the other hand, ABA-pretreated seedlings under chilling stress increased superoxide dismutase and guaiacol peroxidase activities and lowered concentrations of other antioxidants compared with untreated chilling-stressed plants. These seedlings showed concomitant decreases in foliage damage symptoms, and levels of malondialdehyde and H 2 O 2 . Induction of Mn-SOD and POD was observed in chilling-stressed plants treated with ABA. The expression of DHAR1 and DHAR2 was altered by chilling stress, but it was higher in the presence than in the absence of ABA at 24 h. Overall, the results indicate that exogenous application of ABA increases tolerance of plants to chilling-induced oxidative damage, mainly by enhancing superoxide dismutase and guaiacol peroxidase activities and related gene expression.

show abstract

“…After the fruits encountered high-temperature stress at 45°C, APX, GR, and MDAR activity increased initially, but the time for peak activity occurrence varied with individual enzymes, with APX at 1 h, 33.9% higher than the control, and with MDAR and GR at 3 and 5 h, respectively, 10% and 19.4% higher than the control. The results suggested that there was a given sequence in the time response of APX, MDAR, and GR to high-temperature stress, which was related closely to their posts in the cycle (Li et al, 2010). In this experiment, although APX, MDAR, and GR activity showed a certain degree of increase at 25°C, the level of membrane lipid superoxidation in high-temperature treated fruits was significantly higher than that of the control after 3 h, showing that during initial stage of high-temperature treatment, the activity increase for each of the antioxidant enzymes was merely a kind of heat-shock and selfdefensive response.…”

Section: Discussionmentioning

confidence: 80%

“…Due to electrolyte leakage and cell contents oxidization, fruit peel frequently shows typical symptoms like brown or dark color. It has been proved that the AsA-GSH cycle is an important antioxidant system in plants, in which APX, MDAR, and GR are key enzymes that represent the initial, middle, and final posts in the whole cycle (Li et al, 2010). Therefore, the study on changing patterns of relevant enzymes in the AsA-GSH cycle under high temperature and excessive sunlight conditions is helpful to understand how these enzymes response to environmental stress.…”

Section: Introductionmentioning

confidence: 99%

“…Therefore, the study on changing patterns of relevant enzymes in the AsA-GSH cycle under high temperature and excessive sunlight conditions is helpful to understand how these enzymes response to environmental stress. In recent years, a lot of researches have been conducted on AOS and its function on horticultural crops (Li et al, 2010), proving that at hightemperature stress, AOS contents could pile up quickly, which may result in a damage to the function of organelles, and simultaneously, many antioxidant enzymes, such as SOD, POD, APX, MDAR, GR, etc., are inactivated or even damaged (Ding et al, 2008;Zhang et al, 2008;Jin et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of high-temperature stress on the activity of key enzymes in the AsA-GSH cycle in ‘Yali’ pears

Zhang

2010

Front. Agric. China

Self Cite

View full text Add to dashboard Cite

Through treating fruits at higher temperatures, choosing natural fruits on different exposures on a tree canopy and collecting exclusively both sunburn and normal fruits, the metabolic patterns were studied by comparing the activity of key enzymes in the ascorbateglutathione (AsA-GSH) cycle including ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR), and glutathione reductase (GR). The results indicated that the activity of three enzymes increased under around less than 35°C acclimating conditions, with no significant changes in membrane electrolyte leakage. The activity of APX, MDAR, and GR rose during the initial stage when fruits were treated at 45°C but decreased significantly as treating time extended. A time response existed in APX, MDAR, and GR to high temperature. For example, APX activity reached the maximum when fruits were treated for 1 h, however, MDAR and GR showed the peak when fruits were treated for 3 h and 5 h, respectively, implying the possible acting sequence relationship of three enzymes in the AsA-GSH cycle. In view of the whole cycle, APX served as the first enzyme directly scavenging active oxygen species, followed by a series of chain reactions to regenerate ascorbic acid (AsA), and GR served as the last post in the cycle. Because various ecological conditions existed in a tree canopy, there was a significant difference in the enzymatic activity among fruits bearing on either exterior or interior canopy. A significantly higher activity of APX and MDAR was found with exterior fruits, compared with interior ones, which may be regarded as a frequent acclimation to high temperature and excessive sunlight.

show abstract

Advances in the research on the AsA-GSH cycle in horticultural crops

Cited by 69 publications

References 46 publications

Selenium Pretreatment Upregulates the Antioxidant Defense and Methylglyoxal Detoxification System and Confers Enhanced Tolerance to Drought Stress in Rapeseed Seedlings

Selenium Pretreatment Upregulates the Antioxidant Defense and Methylglyoxal Detoxification System and Confers Enhanced Tolerance to Drought Stress in Rapeseed Seedlings

Exogenous abscisic acid increases antioxidant enzymes and related gene expression in pepper (Capsicum annuum) leaves subjected to chilling stress

Effect of high-temperature stress on the activity of key enzymes in the AsA-GSH cycle in ‘Yali’ pears

Contact Info

Product

Resources

About