The regulatory mechanism of soil cadmium (Cd) on antioxidases in sorghum was studied using 3 sorghum species viz., sweet sorghum [Sorghum bicolor (L.)] Moench. cv. Hunnigreen, sorghum hybrid sudangrass (Sorghum b...The regulatory mechanism of soil cadmium (Cd) on antioxidases in sorghum was studied using 3 sorghum species viz., sweet sorghum [Sorghum bicolor (L.)] Moench. cv. Hunnigreen, sorghum hybrid sudangrass (Sorghum bicolor × S. sudanense, cv. Everlush) and sudangrass [Sorghum sudanense (Piper) Stapf cv. Xinjiang]. The results showed that low concentrations of Cd^2+ (410 mg kg-0 induced the activities of 4 antioxidases in leaves of the 3 species of sorghum, but high Cd^2+ concentrations (≥ 50 mg kg-0 significantly reduced the activities of all the four antioxidases. The glutathione (GSH) contents in leaves of the 3 species of sorghum correlated positively with the Cd^2+ concentrations. The maximum antioxidase activities were observed at the elongation stage of sorghum during the whole growth period.展开更多
With the potato variety Xishu 1 as the test materials, this paper adopted tissue culture to study the effect of Pb and Cd stress with different mass fractions on potato growth and the antioxidase system. The results s...With the potato variety Xishu 1 as the test materials, this paper adopted tissue culture to study the effect of Pb and Cd stress with different mass fractions on potato growth and the antioxidase system. The results showed that under the stress of Pb (200 mg/kg) and Cd (20 mg/kg), growth of potato had no obvious difference with that in control group; under the stress of Pb ( 〉200 mg/kg) and Cd ( 〉20 mg/kg), potato growth suspended, and its physiological indexes such as dry weight, plant height, root number, root length were inhibited obviously. With the increasing mass fraction of Pb, relative electrical conductivity, MDA and proline of potato leaves showed the tendency of increase, and the results in high mass fraction treatments showed significant difference with those in the control group (P 〈 0.05 ), CAT, POD and SOD activity of leaves increased greatly with the increasing mass fraction. In the Pb stress treatment (200 mg/kg), relative electrical conductivity, MDA and proline of potato leaves showed no obvious difference with those in the control group, and the results in high mass fraction treatments were significantly higher than those in the control group ( P 〈 O. 05 ), CAT and SOD activity increased greatly with the increasing mass fraction ( P 〈 0.05 ). Under the stress of Pb and Cd, synthesis of soluble protein in potato leaves was strongly inhibited. The results showed that potato was tolerant to Pb and Cd of lower mass fraction, and damage of potato caused by Pb and Cd stress could be relieved by improving activity of antioxidase and reducing peroxidation of membrane lipid, and the tolerance reduced with the increase of stress.展开更多
To investigate the effects of ultraviolet blood irradiation and oxygenation (UBIO) on free radicals and antioxidase after spinal cord injury in rabbits Methods Totally, 186 rabbits were used and divided randomly in...To investigate the effects of ultraviolet blood irradiation and oxygenation (UBIO) on free radicals and antioxidase after spinal cord injury in rabbits Methods Totally, 186 rabbits were used and divided randomly into four experimental groups: control (n=6), blood transfusion (n=24), injured (n=96) and treatment (n=60) groups The relative intensity of free radical (FR) signals, malondialdehyde (MDA) content, as well as the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH PX) were compared among the four groups at 6, 24, 48, and 72 hours and 6 days after injury Results The relative intensity of FR signals in spinal cord tissue in the injured group increased at 48 hours and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group MDA content in blood in the injured group increased and showed a striking difference at 6, 24 and 48 hours and showed a significant difference at 72 hours and 6 days after injury compared with the control group In the treatment group, MDA content in blood decreased and showed a significant difference at 48 hours compared with the injured group MDA content in spinal cord tissue increased in the injured group and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group at the corresponding times The activity of SOD in blood and spinal cord tissue decreased in the injured group and showed a striking difference compared with the control group; in the treatment group, it increased and showed a striking difference compared with the injured group at the corresponding times The changes in activity of GSH PX in blood and spinal cord tissue were similar to that in SOD No significant difference was observed between the blood transfusion and control groups Conclusion UBIO can ease free radical damages and elevate the activity of antioxidases after spinal cord injury in rabbits展开更多
Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty ...Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty chronic glomerulonephritis patients (CGNP) and eighty healthy adult volunteers (HAV) were enrolled in a random control study, in which concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and beta-carotene (?CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric assays. Results Compared with the average values of the above biochemical parameters in the HAV group, the average values of NO in plasma, and LPO in plasma and erythrocytes in the CGNP group were significantly increased (P = 0.0001), while those of VC, VE and -CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CGNP group were significantly decreased (P = 0.0001). Pearson product-moment correlation analysis showed that with increase of the concentration of blood creatinine as well as prolongation of the course of disease in the CGNP, the concentrations of NO in plasma, and LPO in plasma and erythrocytes in the CGNP increased gradually, while the concentrations of VC, VE and ?CAR in plasma as well as the activities of SOD, CAT and GPX in erythrocytes in the CGNP decreased gradually (P = 0.002454 0.000001). The relative risk ratio (RR) of the above biochemical parameters reflecting oxidative damages in the bodies of CGNP ranged from 6.061 to 72.429. The reliability coefficient (alpha) that the above biochemical parameters were used to reflect the oxidative damages of the CGNP was 0.8137, standardized item alpha = 0.9728, Hotelling抯 T-Squared = 1135680.191, F = 53274.6478, P = 0.000001. Conclusions The findings in this study show that in the bodies of CGNP a series of free radical chain reactions result in severe pathological aggravation and induce oxidative damages in their bodies. Therefore, suitable dose of antioxidants should be supplemented to them so as to alleviate oxidative damages in their bodies.展开更多
To estimate the impact of copying on the indoor air quality, and to investigate whether ozone emitted during such a process induces pathological oxidative stress and potential oxidative damage in the bodies of operato...To estimate the impact of copying on the indoor air quality, and to investigate whether ozone emitted during such a process induces pathological oxidative stress and potential oxidative damage in the bodies of operators. Methods 67 copying operators (CO) and 67 healthy volunteers (HV) were enrolled in a random control study, in which levels of lipoperoxide (LPO) in plasma and erythrocytes, and levels of vitamin C (VC), vitamin E (VE) and b-carotene (b-CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined by spectrophotometric methods. Results Compared with the HV group, the average values of LPO in plasma and erythrocytes in the CO group were significantly increased (P<0.0001), while those of VC, VE and b-CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CO group were significantly decreased (P<0.0001). Pearson product-moment correlation analysis showed that with increase of ozone level in copying sites and duration of exposure to ozone, the values of LPO in plasma and erythrocytes in the bodies of operators were gradually increased,while those of VC, VE, b-CAR, SOD, CAT and GPX were decreased in the same manner. Odds ratio (OR) of risk of biochemical parameters reflecting potential oxidative damage of the copying operators ranged from 4.440 to 13.516, and 95 % CI of OR was from 2.113 to 34.061. Reliability coefficient () of the biochemical parameters used to reflect the potential oxidative damage of the operators was 0.8156, standardized item =0.9929, P<0.0001. Conclusion Findings in the present study suggest that there exist a series of free radical chain reactions and pathological oxidative stress induced by high dose ozone in the operators, thereby causing potential oxidative and lipoperoxidative damages in their bodies.展开更多
Two indica rice (Oryza sativa L.) materials, Xieqingzao B (sensitive to heat stress) and 082 (tolerant to heat stress) were used to study the role of brassinolide (BR) in protection of rice seedlings from heat...Two indica rice (Oryza sativa L.) materials, Xieqingzao B (sensitive to heat stress) and 082 (tolerant to heat stress) were used to study the role of brassinolide (BR) in protection of rice seedlings from heat stress. Young seedlings were subjected to high temperature (38℃/30℃) and sprayed with 0.005 mg/L of BR. Analysis was conducted on the contents of chlorophyll, protein and malondialdehyde (MDA), the leakage of electrolyte, the activities of peroxidase (POD) and superoxide dismutase (SOD) and their isozymes expression levels in leaves. Under the high temperature treatment, application of BR significantly increased the contents of chlorophyll and protein, and the activities of POD and SOD, and reduced the content of MDA and the leakage of electrolyte in the leaves of the heat-sensitive material Xieqingzao B, whereas BR had less effect on those of the heat-tolerant material 082 relatively. The BR treatment enhanced the expression of POD isozymes in the leaves of both materials. Under the high temperature stress and BR treatment, the expression of four SOD isozymes reduced in 082, but the expression of two SOD isozymes increased in Xieqingzao B. This suggests that BR plays an important role in protection of rice seedlings from heat stress by enhancing the activities or expression level of protective enzymes in the leaves. The materials with various heat-tolerance might differ in the mechanism of response to heat stress with BR application.展开更多
Objective To investigate whether pregnancy-induced hypertension (PIH) may increase oxidative stress in women with PIH, and to explore the mechanisms by which PIH may increase oxidative stress and potential free radi...Objective To investigate whether pregnancy-induced hypertension (PIH) may increase oxidative stress in women with PIH, and to explore the mechanisms by which PIH may increase oxidative stress and potential free radical damage. Methods Seventy women with PIH and seventy women with uncomplicated normotensive pregnancy (UNP) whose age, nutritional conditions, levels of hemoglobin and albumin were all matched, were enrolled in a randomized controlled trial. Their plasma concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE), and β-carotene (β-CAR) as well as their erythrocyte malondialdehyde (MDA), and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) were determined by spcctrophotometry. Results Compared with average values of the above experimental parameters in the women with UNP, the average value of erythrocyte MDA in the women with PIH significantly increased (P〈0.0001), while the average values of plasma NO, VC, VE, and β-CAR as well as those of erythrocyte SOD, CAT, and GPX in the women with PIH significantly decreased (P〈0.0005-0.0001). The findings from partial correlation analysis (controlling for age) for 70 women with PIH showed that with elevated systolic blood pressure (SBP) and diastolic blood pressure (DBP), MDA value gradually increased (P〈0.001), and NO, VC, VE, β-CAR, SOD, CAT, and GPX values gradually decreased (P〈0.02-0.001). The findings from reliability analysis for NO, VC, VE, β-CAR, SOD, CAT, GPX, and MDA values used to reflect increased oxidative stress and potential free radical damage in women with PIH showed that the reliability coefficients (alpha, 8 items) = 0.7062, P〈 0.0001, and the standardized item alpha = 0.9116, P〈 0.0001. Conclusion The findings in the present research suggest that pregnancy-induced hypertension can increase oxidative stress and potential free radical damage in women with pregnancy-induced hypertension.展开更多
Objective To study the state of oxidative stress in patients with acute coxsackie virusmyocarditis (ACM), and to investigate the pathological chain reactions of a series of freeradicals and oxidative and lipoperoxi...Objective To study the state of oxidative stress in patients with acute coxsackie virusmyocarditis (ACM), and to investigate the pathological chain reactions of a series of freeradicals and oxidative and lipoperoxidative damages in their bodies. Methods Eighty ACMpatients and 80 healthy adult volunteers (HAV) were enrolled in a case-control study, inwhich concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma andLPO in erythrocytes (RBC), vitamin C (VC), vitamin E (VE) and b-carotene (b-CAR) inplasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathioneperoxidase (GSH-Px) in RBC were determined by using spectrophotometric assays. ResultsCompared with the average values (AV) of the above biochemical parameters (BP) in theHAV group, the AV of NO in plasma, and LPO in plasma and RBC in the ACM group weresignificantly increased (P=0.0001), while the AV of VC, VE, b-CAR, SOD, CAT and GSH-Px in the ACM group were significantly decreased (P=0.0001). The values of the above BPwere used to estimate the relative risk ratio (RR) between the ACM group and the HAVgroup; the RR and its 95 % confidence interval were 12.467 (5.745~27.051), 4.333(2.126~8.834), 6.517 (3.225~13.618), 3.310 (1.598~6.858), 31.000 (12.611~76.201),4.663 (2.228~9.759), 11.769 (5.440~25.462), 3.043 (1.486~6.229) and 6.594 (3.045~14.281)respectively, and their P levels ranged from 0.002 to 0.0001. The results were asfollows: D = 22.143 - 0.017SOD + 0.008NO + 0.244LPO in RBC, Eigenvalue = 13.659,Canonical correlation = 0.965, Wilks’λ= 0.068, c2 = 420.212, P = 0.0001. The correct rateof discrimination to the ACM group and to the HAV group was 87.5% and 95.0 %, respectively,and 91.3 % of originally grouped cases was correctly classified. Conclusion The findingsin this study suggested that the oxidative stress in bodies of ACM patients was severelyaggravated, and marked high oxidative constituents and low antioxidants and antioxidasesin the human body might increase the relative risk of inducing acute coxsackie virusmyocarditis, and measuring the values of NO in plasma, SOD and LPO in RBC mightincrease the correct rates of discriminatory analysis of the ACM.展开更多
The effect and the mechanism of action of lanthanum, cerium and neodymium on aged seeds of spinach were studied. By LaCl_3, CeCl_3, and NdCl_3 treatment, the germination rate, germination index and vigor index of aged...The effect and the mechanism of action of lanthanum, cerium and neodymium on aged seeds of spinach were studied. By LaCl_3, CeCl_3, and NdCl_3 treatment, the germination rate, germination index and vigor index of aged spinach seeds are increased and the activities of superoxide dismutase, catalase and peroxidase are enhanced. Moreover the ·O_2^- and malondialdehyde content are decreased and the cell membrane permeability of aged spinach seeds is reduced. Among these three rare earth elements, Ce treatment enhances vigor of aged seeds most significantly, that of Nd treatment secondly and La treatment is not as effective as the other two treatments. The reason may be from 4f electron characteristic and alternation valence of REEs.展开更多
Objective To investigate whether photochemical smog emitted during the process of electric arc welding might cause oxidative stress and potential oxidative damage in the bodies of welding operators. Methods Seventy...Objective To investigate whether photochemical smog emitted during the process of electric arc welding might cause oxidative stress and potential oxidative damage in the bodies of welding operators. Methods Seventy electric arc welding operators (WOs) and 70 healthy volunteers (HVs) were enrolled in a randomized controlled study design, in which the levels of vitamin C (VC) and vitamin E (VE) in plasma as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and the level of lipoperoxide (LPO) in erythrocytes were determined by spectrophotometry. Results Compared with the average values of the above experimental parameters in the HVs group, the average values of VC and VE in plasma as well as those of SOD, CAT and GPX in erythrocytes in the WOs group were significantly decreased (P<0.005-0.0001), while the average value of LPO in erythrocytes in the WOs group was significantly increased (P<0.0001). The findings from the partial correlation analysis on the controlling of age suggested that with a prolonged duration of exposure to photochemical smog the values of VC, VE, SOD, and GPX, except for CAT, in the WOs were decreased gradually (P<0.05-0.005), the value of LPO in the WOs was increased gradually (P<0.001), and that with the ozone dose increased in the air in each worksite VC, VE, SOD, CAT and GPX decreased (P<0.005-0.001), but LPO increased (P<0.001). The findings from the reliability analysis for the VC, VE, SOD, CAT, GPX, and LPO values which were used to reflect oxidative stress and potential oxidative damage in the WOs showed that the reliability coefficients?alpha (6 items) was 0.8021, P<0.0001, and that the standardized item alpha was 0.9577, P<0.0001. Conclusion Findings in the present study suggest that there exists an oxidative stress induced by long-term exposure to photochemical smog in the bodies of WOs, thereby causing potential oxidative and lipoperoxidative damages in their bodies.展开更多
Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress an...Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress and potential free radical damage to chronic constipation patients (CCPs). Methods Sixty CCPs and sixty healthy child volunteers (HCVs) whose ages, gender and others were matched for the CCPs were enrolled in a randomized controlled study, in which levels of vitamin C (VC) and vitamin E (VE) in plasma as well as activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with average values of the above biochemical parameters in the HCVs group, the average values of VC and VE in plasma as well as those of SOD and CAT in erythrocytes in the CCPs group were significantly decreased (P<0.0001). Linear regression and bivariate correlation analysis showed that with prolonged course of the CCPs, the levels of VC and VE in plasma as well as the activities of SOD and CAT in erythrocytes in the CCPs were decreased gradually (P<0.0001). Conclusion The findings in the present study suggest that chronic childhood constipation causes oxidative stress and potential free radical damage to children with chronic constipation.展开更多
In order to explore the salt-tolerance of Narcissus pseudonarcissus and enrich its cultivation and application forms. In this experiment, “Manly”, “Dutch” and “Wilden” daffodils were used as test materials. NaCl...In order to explore the salt-tolerance of Narcissus pseudonarcissus and enrich its cultivation and application forms. In this experiment, “Manly”, “Dutch” and “Wilden” daffodils were used as test materials. NaCl stress was applied at different concentrations, and the corresponding physiological indexes were measured at three time nodes: bolting stage, early flowering stage and blooming stage. The results showed that all three showed some resistance under low concentration salt stress, in which, SOD, POD enzyme activity, chlorophyll proline and soluble sugar content increased, while MDA content decreased. The physiological metabolism of the three was disturbed under high concentration of salt stress, in which, SOD, POD enzyme activity and chlorophyll content decreased, while MDA, proline and soluble sugar content increased. With the extension of stress time, the injury was gradually deepened and the salt tolerance of the three varieties is “Dutch”, “Wilden” and “Manly” in order.展开更多
OBJECTIVE To research the effect of Rhodiolae on cognitive function on dementia rats and to investigate its potential mechanism.METHODS Established dementia model via injecting ibotenic acid into basal nuclei,and rand...OBJECTIVE To research the effect of Rhodiolae on cognitive function on dementia rats and to investigate its potential mechanism.METHODS Established dementia model via injecting ibotenic acid into basal nuclei,and randomly divided the model rats into model group,Aricept group(1.4 mg·kg-1)and Rhodiolae group(0.14 mg·kg-1),moreover the sham group was built byinjecting normal saline.All animals received homologous drugs after modeling 1 week,and the sham group and model group were gave isometric normal saline(10 mL·kg-1),1/d.Morris water maze was used to evaluate the change of cognitive function after the rats were treated 40 d,and pathomorphism in CA1 and cerebral cortex were observed by Nissl staining and the numbers of nerve cell in these areas were counted.The concentration of MDA,H2O2,CAT,SOD and GR in brain tissue were detected by spectrophotography.RESULTS Compared to model group,the escape latency of Rhodiolae groups〔(31.10±20.97)s compare to(51.07±13.04)s〕was shortened but it hadn′t statistical difference,and the total swimming distance〔(8469.88±4724.74)cm compare to(15862.17±1315.69)cm〕was shortened obviously,furthermore the times entered the target quadrant〔(9.50±1.87)times compare to(6.50±1.38)times〕and the percentage in target quadrant〔(33.87±4.47)%compare to(26.17±2.58)%〕were evidently increased.Moderate shrinkage of nucleus of neurons in cerebral cortex of model rats,mild hyperplasia of glial cells and loosely neuron was also observed in CA1 area,but those lesions were distinctly ameliorated in Rhodiolae groups.What′s more,the numbers of nerve cells in CA1〔(70.40±4.00)compare to(45.50±4.95)〕and cerebral cortex〔(63.00±5.29)compare to(42.40±11.87)〕of Rhodiolae groups were obviously increased.In addition,compared to model group,the content of MDA〔(14.72±4.42)compare to(19.99±4.70)g protein·L-1〕and H2O2〔(60.07±6.38)mmol·L-1compare to(76.37±6.06)mmol·L-1〕were evidently decreased,the activity of GSH〔(41.30±14.81)k U·g-1protein compare to(15.93±3.59)k U·g-1protein〕was visibly increased,and the activity of SOD〔(5.74±3.76)g protein·L-1compare to(2.72±1.09)g protein·L-1〕and CAT〔(210.45±60.11)k U·g-1protein compare to(171.48±56.50)k U·g-1protein〕were also increased but without statistical difference.CONCLUSION Rhodiolae improve learning and remembering function,ameliorate pathological changes and protect neuronal loss which respond to decrease the oxidative products and enhance the activity of antioxidase.展开更多
An investigation on the organic degradation products and selenium in the pathogenesis of Kaschin-Beck disease was carried out. The results demonstrated that the organic degradation products existed in food and drinkin...An investigation on the organic degradation products and selenium in the pathogenesis of Kaschin-Beck disease was carried out. The results demonstrated that the organic degradation products existed in food and drinking water were the pathogens of the KBD; their leading pathological process of cells would be 'membrane injury' due to peroxide. As GSH-Px is a selenium contained enzyme, therefore insufficient selenium would be one of the most important conditions to cause KBD.展开更多
Humic acids, especially FA in fractions, contain more oxygen functional groups. In this experiment, on the basis of confirming the action of humic acids on KBD, what was studied is the biological effects of one of mai...Humic acids, especially FA in fractions, contain more oxygen functional groups. In this experiment, on the basis of confirming the action of humic acids on KBD, what was studied is the biological effects of one of main oxygen functional groups, hydroxy group (-OH). The results indicate that inducing pathologic process of KBD, obviously decrease the GSH-Px activity and induce peroxidation membrane injury of tissue. The SOD activity increase in the tissues caused by oxygen functional groups showed that enhancing of free radical reaction should not be neglected.展开更多
Poor adventitious root formation is a major obstacle in micropropagation and in conventional propagation. The effects of LaCl_3 on root growth and deferring the root ageing of peach plantlet in vitro were investigated...Poor adventitious root formation is a major obstacle in micropropagation and in conventional propagation. The effects of LaCl_3 on root growth and deferring the root ageing of peach plantlet in vitro were investigated. The results show that the optimum concentration of LaCl_3 (2.5 μmol·L -1) in the rooted medium can significantly increase the rooting rate, the root length and the fresh weight, promote the activities of superoxide dismutase (SOD); catalase (CAT) and peroxidase (POD) and decrease the production rate of O_2 ·-, the malondialdehyde (MDA) contents and the plasma membrane permeability. There are important theory meaning and practical value in applying LaCl_3 in the rooting medium to raise the rate of rooting and transplant for stone fruit tree.展开更多
To understand the response characteristics of soybean seedling resistance systems to high-temperature stress,the spring soybean varieties HN44 and HN65 were selected in this study as the experimental materials,as they...To understand the response characteristics of soybean seedling resistance systems to high-temperature stress,the spring soybean varieties HN44 and HN65 were selected in this study as the experimental materials,as they had substantial differences in stress resistance.Soybean physiological status was studied under high-temperature stress.Sand culture was used in the experiment,and soybeans at the seedling stage were treated with high-temperature stress.The results showed that the activity of antioxidases and osmotic regulatory substance contents in soybean increased under high-temperature treatment for a certain period of time,the activity of antioxidases and osmotic regulatory substance contents decreased after continuous treatment,and high temperatures continuously increased malondialdehyde contents in the two varieties.At high temperatures,the antioxidant activity and osmotic regulator contents of HN44 were higher than those of HN65,and the malondialdehyde contents of HN44 were higher than those of HN65.The above results showed that HN44 soybeans exhibited significantly higher resistance to high-temperature stress than HN65 variety.展开更多
Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growt...Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growth rate,dry weight,fresh weight and relative water content of the plants were determined. After 6h of treatment,the activity and gene expression of three antioxidant enzymes,superoxide dismutase( SOD),catalase( CAT) and ascorbate peroxidase( APX) in plants,were measured. The results showed that the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in collard seedlings were higher in the treatment of salt stress with the addition of 0. 05 mmol/L exogenous H_2O_2 than in the simple salt stress treatment; and when endogenous H_2O_2 was removed,the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in plant seedlings were lower than those under simple salt stress. It is speculated that under salt stress,H_2O_2 is involved in the regulation of antioxidant defense gene expression,and it might be an important regulator of salt-induced antioxidant system in collard leaves.展开更多
基金supported by the Public Service(Agriculture)Special Research Fund,China(nyhyzx07-2022)
文摘The regulatory mechanism of soil cadmium (Cd) on antioxidases in sorghum was studied using 3 sorghum species viz., sweet sorghum [Sorghum bicolor (L.)] Moench. cv. Hunnigreen, sorghum hybrid sudangrass (Sorghum bicolor × S. sudanense, cv. Everlush) and sudangrass [Sorghum sudanense (Piper) Stapf cv. Xinjiang]. The results showed that low concentrations of Cd^2+ (410 mg kg-0 induced the activities of 4 antioxidases in leaves of the 3 species of sorghum, but high Cd^2+ concentrations (≥ 50 mg kg-0 significantly reduced the activities of all the four antioxidases. The glutathione (GSH) contents in leaves of the 3 species of sorghum correlated positively with the Cd^2+ concentrations. The maximum antioxidase activities were observed at the elongation stage of sorghum during the whole growth period.
基金Sponsored by Key Program of Sichuan Provincial Department of Education(12ZA149)
文摘With the potato variety Xishu 1 as the test materials, this paper adopted tissue culture to study the effect of Pb and Cd stress with different mass fractions on potato growth and the antioxidase system. The results showed that under the stress of Pb (200 mg/kg) and Cd (20 mg/kg), growth of potato had no obvious difference with that in control group; under the stress of Pb ( 〉200 mg/kg) and Cd ( 〉20 mg/kg), potato growth suspended, and its physiological indexes such as dry weight, plant height, root number, root length were inhibited obviously. With the increasing mass fraction of Pb, relative electrical conductivity, MDA and proline of potato leaves showed the tendency of increase, and the results in high mass fraction treatments showed significant difference with those in the control group (P 〈 0.05 ), CAT, POD and SOD activity of leaves increased greatly with the increasing mass fraction. In the Pb stress treatment (200 mg/kg), relative electrical conductivity, MDA and proline of potato leaves showed no obvious difference with those in the control group, and the results in high mass fraction treatments were significantly higher than those in the control group ( P 〈 O. 05 ), CAT and SOD activity increased greatly with the increasing mass fraction ( P 〈 0.05 ). Under the stress of Pb and Cd, synthesis of soluble protein in potato leaves was strongly inhibited. The results showed that potato was tolerant to Pb and Cd of lower mass fraction, and damage of potato caused by Pb and Cd stress could be relieved by improving activity of antioxidase and reducing peroxidation of membrane lipid, and the tolerance reduced with the increase of stress.
文摘To investigate the effects of ultraviolet blood irradiation and oxygenation (UBIO) on free radicals and antioxidase after spinal cord injury in rabbits Methods Totally, 186 rabbits were used and divided randomly into four experimental groups: control (n=6), blood transfusion (n=24), injured (n=96) and treatment (n=60) groups The relative intensity of free radical (FR) signals, malondialdehyde (MDA) content, as well as the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH PX) were compared among the four groups at 6, 24, 48, and 72 hours and 6 days after injury Results The relative intensity of FR signals in spinal cord tissue in the injured group increased at 48 hours and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group MDA content in blood in the injured group increased and showed a striking difference at 6, 24 and 48 hours and showed a significant difference at 72 hours and 6 days after injury compared with the control group In the treatment group, MDA content in blood decreased and showed a significant difference at 48 hours compared with the injured group MDA content in spinal cord tissue increased in the injured group and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group at the corresponding times The activity of SOD in blood and spinal cord tissue decreased in the injured group and showed a striking difference compared with the control group; in the treatment group, it increased and showed a striking difference compared with the injured group at the corresponding times The changes in activity of GSH PX in blood and spinal cord tissue were similar to that in SOD No significant difference was observed between the blood transfusion and control groups Conclusion UBIO can ease free radical damages and elevate the activity of antioxidases after spinal cord injury in rabbits
文摘Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty chronic glomerulonephritis patients (CGNP) and eighty healthy adult volunteers (HAV) were enrolled in a random control study, in which concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and beta-carotene (?CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric assays. Results Compared with the average values of the above biochemical parameters in the HAV group, the average values of NO in plasma, and LPO in plasma and erythrocytes in the CGNP group were significantly increased (P = 0.0001), while those of VC, VE and -CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CGNP group were significantly decreased (P = 0.0001). Pearson product-moment correlation analysis showed that with increase of the concentration of blood creatinine as well as prolongation of the course of disease in the CGNP, the concentrations of NO in plasma, and LPO in plasma and erythrocytes in the CGNP increased gradually, while the concentrations of VC, VE and ?CAR in plasma as well as the activities of SOD, CAT and GPX in erythrocytes in the CGNP decreased gradually (P = 0.002454 0.000001). The relative risk ratio (RR) of the above biochemical parameters reflecting oxidative damages in the bodies of CGNP ranged from 6.061 to 72.429. The reliability coefficient (alpha) that the above biochemical parameters were used to reflect the oxidative damages of the CGNP was 0.8137, standardized item alpha = 0.9728, Hotelling抯 T-Squared = 1135680.191, F = 53274.6478, P = 0.000001. Conclusions The findings in this study show that in the bodies of CGNP a series of free radical chain reactions result in severe pathological aggravation and induce oxidative damages in their bodies. Therefore, suitable dose of antioxidants should be supplemented to them so as to alleviate oxidative damages in their bodies.
文摘To estimate the impact of copying on the indoor air quality, and to investigate whether ozone emitted during such a process induces pathological oxidative stress and potential oxidative damage in the bodies of operators. Methods 67 copying operators (CO) and 67 healthy volunteers (HV) were enrolled in a random control study, in which levels of lipoperoxide (LPO) in plasma and erythrocytes, and levels of vitamin C (VC), vitamin E (VE) and b-carotene (b-CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined by spectrophotometric methods. Results Compared with the HV group, the average values of LPO in plasma and erythrocytes in the CO group were significantly increased (P<0.0001), while those of VC, VE and b-CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CO group were significantly decreased (P<0.0001). Pearson product-moment correlation analysis showed that with increase of ozone level in copying sites and duration of exposure to ozone, the values of LPO in plasma and erythrocytes in the bodies of operators were gradually increased,while those of VC, VE, b-CAR, SOD, CAT and GPX were decreased in the same manner. Odds ratio (OR) of risk of biochemical parameters reflecting potential oxidative damage of the copying operators ranged from 4.440 to 13.516, and 95 % CI of OR was from 2.113 to 34.061. Reliability coefficient () of the biochemical parameters used to reflect the potential oxidative damage of the operators was 0.8156, standardized item =0.9929, P<0.0001. Conclusion Findings in the present study suggest that there exist a series of free radical chain reactions and pathological oxidative stress induced by high dose ozone in the operators, thereby causing potential oxidative and lipoperoxidative damages in their bodies.
基金This work was supported by the National Natural Science Foundation(Grant No.30671225)the Natural Science Foundation of Jiangsu Province(Grant No.BK2006069)Nantong University School Program(Grant No.06Z108).
文摘Two indica rice (Oryza sativa L.) materials, Xieqingzao B (sensitive to heat stress) and 082 (tolerant to heat stress) were used to study the role of brassinolide (BR) in protection of rice seedlings from heat stress. Young seedlings were subjected to high temperature (38℃/30℃) and sprayed with 0.005 mg/L of BR. Analysis was conducted on the contents of chlorophyll, protein and malondialdehyde (MDA), the leakage of electrolyte, the activities of peroxidase (POD) and superoxide dismutase (SOD) and their isozymes expression levels in leaves. Under the high temperature treatment, application of BR significantly increased the contents of chlorophyll and protein, and the activities of POD and SOD, and reduced the content of MDA and the leakage of electrolyte in the leaves of the heat-sensitive material Xieqingzao B, whereas BR had less effect on those of the heat-tolerant material 082 relatively. The BR treatment enhanced the expression of POD isozymes in the leaves of both materials. Under the high temperature stress and BR treatment, the expression of four SOD isozymes reduced in 082, but the expression of two SOD isozymes increased in Xieqingzao B. This suggests that BR plays an important role in protection of rice seedlings from heat stress by enhancing the activities or expression level of protective enzymes in the leaves. The materials with various heat-tolerance might differ in the mechanism of response to heat stress with BR application.
文摘Objective To investigate whether pregnancy-induced hypertension (PIH) may increase oxidative stress in women with PIH, and to explore the mechanisms by which PIH may increase oxidative stress and potential free radical damage. Methods Seventy women with PIH and seventy women with uncomplicated normotensive pregnancy (UNP) whose age, nutritional conditions, levels of hemoglobin and albumin were all matched, were enrolled in a randomized controlled trial. Their plasma concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE), and β-carotene (β-CAR) as well as their erythrocyte malondialdehyde (MDA), and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) were determined by spcctrophotometry. Results Compared with average values of the above experimental parameters in the women with UNP, the average value of erythrocyte MDA in the women with PIH significantly increased (P〈0.0001), while the average values of plasma NO, VC, VE, and β-CAR as well as those of erythrocyte SOD, CAT, and GPX in the women with PIH significantly decreased (P〈0.0005-0.0001). The findings from partial correlation analysis (controlling for age) for 70 women with PIH showed that with elevated systolic blood pressure (SBP) and diastolic blood pressure (DBP), MDA value gradually increased (P〈0.001), and NO, VC, VE, β-CAR, SOD, CAT, and GPX values gradually decreased (P〈0.02-0.001). The findings from reliability analysis for NO, VC, VE, β-CAR, SOD, CAT, GPX, and MDA values used to reflect increased oxidative stress and potential free radical damage in women with PIH showed that the reliability coefficients (alpha, 8 items) = 0.7062, P〈 0.0001, and the standardized item alpha = 0.9116, P〈 0.0001. Conclusion The findings in the present research suggest that pregnancy-induced hypertension can increase oxidative stress and potential free radical damage in women with pregnancy-induced hypertension.
文摘Objective To study the state of oxidative stress in patients with acute coxsackie virusmyocarditis (ACM), and to investigate the pathological chain reactions of a series of freeradicals and oxidative and lipoperoxidative damages in their bodies. Methods Eighty ACMpatients and 80 healthy adult volunteers (HAV) were enrolled in a case-control study, inwhich concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma andLPO in erythrocytes (RBC), vitamin C (VC), vitamin E (VE) and b-carotene (b-CAR) inplasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathioneperoxidase (GSH-Px) in RBC were determined by using spectrophotometric assays. ResultsCompared with the average values (AV) of the above biochemical parameters (BP) in theHAV group, the AV of NO in plasma, and LPO in plasma and RBC in the ACM group weresignificantly increased (P=0.0001), while the AV of VC, VE, b-CAR, SOD, CAT and GSH-Px in the ACM group were significantly decreased (P=0.0001). The values of the above BPwere used to estimate the relative risk ratio (RR) between the ACM group and the HAVgroup; the RR and its 95 % confidence interval were 12.467 (5.745~27.051), 4.333(2.126~8.834), 6.517 (3.225~13.618), 3.310 (1.598~6.858), 31.000 (12.611~76.201),4.663 (2.228~9.759), 11.769 (5.440~25.462), 3.043 (1.486~6.229) and 6.594 (3.045~14.281)respectively, and their P levels ranged from 0.002 to 0.0001. The results were asfollows: D = 22.143 - 0.017SOD + 0.008NO + 0.244LPO in RBC, Eigenvalue = 13.659,Canonical correlation = 0.965, Wilks’λ= 0.068, c2 = 420.212, P = 0.0001. The correct rateof discrimination to the ACM group and to the HAV group was 87.5% and 95.0 %, respectively,and 91.3 % of originally grouped cases was correctly classified. Conclusion The findingsin this study suggested that the oxidative stress in bodies of ACM patients was severelyaggravated, and marked high oxidative constituents and low antioxidants and antioxidasesin the human body might increase the relative risk of inducing acute coxsackie virusmyocarditis, and measuring the values of NO in plasma, SOD and LPO in RBC mightincrease the correct rates of discriminatory analysis of the ACM.
文摘The effect and the mechanism of action of lanthanum, cerium and neodymium on aged seeds of spinach were studied. By LaCl_3, CeCl_3, and NdCl_3 treatment, the germination rate, germination index and vigor index of aged spinach seeds are increased and the activities of superoxide dismutase, catalase and peroxidase are enhanced. Moreover the ·O_2^- and malondialdehyde content are decreased and the cell membrane permeability of aged spinach seeds is reduced. Among these three rare earth elements, Ce treatment enhances vigor of aged seeds most significantly, that of Nd treatment secondly and La treatment is not as effective as the other two treatments. The reason may be from 4f electron characteristic and alternation valence of REEs.
文摘Objective To investigate whether photochemical smog emitted during the process of electric arc welding might cause oxidative stress and potential oxidative damage in the bodies of welding operators. Methods Seventy electric arc welding operators (WOs) and 70 healthy volunteers (HVs) were enrolled in a randomized controlled study design, in which the levels of vitamin C (VC) and vitamin E (VE) in plasma as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and the level of lipoperoxide (LPO) in erythrocytes were determined by spectrophotometry. Results Compared with the average values of the above experimental parameters in the HVs group, the average values of VC and VE in plasma as well as those of SOD, CAT and GPX in erythrocytes in the WOs group were significantly decreased (P<0.005-0.0001), while the average value of LPO in erythrocytes in the WOs group was significantly increased (P<0.0001). The findings from the partial correlation analysis on the controlling of age suggested that with a prolonged duration of exposure to photochemical smog the values of VC, VE, SOD, and GPX, except for CAT, in the WOs were decreased gradually (P<0.05-0.005), the value of LPO in the WOs was increased gradually (P<0.001), and that with the ozone dose increased in the air in each worksite VC, VE, SOD, CAT and GPX decreased (P<0.005-0.001), but LPO increased (P<0.001). The findings from the reliability analysis for the VC, VE, SOD, CAT, GPX, and LPO values which were used to reflect oxidative stress and potential oxidative damage in the WOs showed that the reliability coefficients?alpha (6 items) was 0.8021, P<0.0001, and that the standardized item alpha was 0.9577, P<0.0001. Conclusion Findings in the present study suggest that there exists an oxidative stress induced by long-term exposure to photochemical smog in the bodies of WOs, thereby causing potential oxidative and lipoperoxidative damages in their bodies.
文摘Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress and potential free radical damage to chronic constipation patients (CCPs). Methods Sixty CCPs and sixty healthy child volunteers (HCVs) whose ages, gender and others were matched for the CCPs were enrolled in a randomized controlled study, in which levels of vitamin C (VC) and vitamin E (VE) in plasma as well as activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with average values of the above biochemical parameters in the HCVs group, the average values of VC and VE in plasma as well as those of SOD and CAT in erythrocytes in the CCPs group were significantly decreased (P<0.0001). Linear regression and bivariate correlation analysis showed that with prolonged course of the CCPs, the levels of VC and VE in plasma as well as the activities of SOD and CAT in erythrocytes in the CCPs were decreased gradually (P<0.0001). Conclusion The findings in the present study suggest that chronic childhood constipation causes oxidative stress and potential free radical damage to children with chronic constipation.
文摘In order to explore the salt-tolerance of Narcissus pseudonarcissus and enrich its cultivation and application forms. In this experiment, “Manly”, “Dutch” and “Wilden” daffodils were used as test materials. NaCl stress was applied at different concentrations, and the corresponding physiological indexes were measured at three time nodes: bolting stage, early flowering stage and blooming stage. The results showed that all three showed some resistance under low concentration salt stress, in which, SOD, POD enzyme activity, chlorophyll proline and soluble sugar content increased, while MDA content decreased. The physiological metabolism of the three was disturbed under high concentration of salt stress, in which, SOD, POD enzyme activity and chlorophyll content decreased, while MDA, proline and soluble sugar content increased. With the extension of stress time, the injury was gradually deepened and the salt tolerance of the three varieties is “Dutch”, “Wilden” and “Manly” in order.
基金The project supported by Key Projects of National Natural Science Foundation of China(81430100)Academic and technical leaders of Sichuan Province to Raise Funds for Funding Projects(2015058)Sichuan Province Youth Science and technology Innovation Research Team(2014TD0007)
文摘OBJECTIVE To research the effect of Rhodiolae on cognitive function on dementia rats and to investigate its potential mechanism.METHODS Established dementia model via injecting ibotenic acid into basal nuclei,and randomly divided the model rats into model group,Aricept group(1.4 mg·kg-1)and Rhodiolae group(0.14 mg·kg-1),moreover the sham group was built byinjecting normal saline.All animals received homologous drugs after modeling 1 week,and the sham group and model group were gave isometric normal saline(10 mL·kg-1),1/d.Morris water maze was used to evaluate the change of cognitive function after the rats were treated 40 d,and pathomorphism in CA1 and cerebral cortex were observed by Nissl staining and the numbers of nerve cell in these areas were counted.The concentration of MDA,H2O2,CAT,SOD and GR in brain tissue were detected by spectrophotography.RESULTS Compared to model group,the escape latency of Rhodiolae groups〔(31.10±20.97)s compare to(51.07±13.04)s〕was shortened but it hadn′t statistical difference,and the total swimming distance〔(8469.88±4724.74)cm compare to(15862.17±1315.69)cm〕was shortened obviously,furthermore the times entered the target quadrant〔(9.50±1.87)times compare to(6.50±1.38)times〕and the percentage in target quadrant〔(33.87±4.47)%compare to(26.17±2.58)%〕were evidently increased.Moderate shrinkage of nucleus of neurons in cerebral cortex of model rats,mild hyperplasia of glial cells and loosely neuron was also observed in CA1 area,but those lesions were distinctly ameliorated in Rhodiolae groups.What′s more,the numbers of nerve cells in CA1〔(70.40±4.00)compare to(45.50±4.95)〕and cerebral cortex〔(63.00±5.29)compare to(42.40±11.87)〕of Rhodiolae groups were obviously increased.In addition,compared to model group,the content of MDA〔(14.72±4.42)compare to(19.99±4.70)g protein·L-1〕and H2O2〔(60.07±6.38)mmol·L-1compare to(76.37±6.06)mmol·L-1〕were evidently decreased,the activity of GSH〔(41.30±14.81)k U·g-1protein compare to(15.93±3.59)k U·g-1protein〕was visibly increased,and the activity of SOD〔(5.74±3.76)g protein·L-1compare to(2.72±1.09)g protein·L-1〕and CAT〔(210.45±60.11)k U·g-1protein compare to(171.48±56.50)k U·g-1protein〕were also increased but without statistical difference.CONCLUSION Rhodiolae improve learning and remembering function,ameliorate pathological changes and protect neuronal loss which respond to decrease the oxidative products and enhance the activity of antioxidase.
文摘An investigation on the organic degradation products and selenium in the pathogenesis of Kaschin-Beck disease was carried out. The results demonstrated that the organic degradation products existed in food and drinking water were the pathogens of the KBD; their leading pathological process of cells would be 'membrane injury' due to peroxide. As GSH-Px is a selenium contained enzyme, therefore insufficient selenium would be one of the most important conditions to cause KBD.
文摘Humic acids, especially FA in fractions, contain more oxygen functional groups. In this experiment, on the basis of confirming the action of humic acids on KBD, what was studied is the biological effects of one of main oxygen functional groups, hydroxy group (-OH). The results indicate that inducing pathologic process of KBD, obviously decrease the GSH-Px activity and induce peroxidation membrane injury of tissue. The SOD activity increase in the tissues caused by oxygen functional groups showed that enhancing of free radical reaction should not be neglected.
文摘Poor adventitious root formation is a major obstacle in micropropagation and in conventional propagation. The effects of LaCl_3 on root growth and deferring the root ageing of peach plantlet in vitro were investigated. The results show that the optimum concentration of LaCl_3 (2.5 μmol·L -1) in the rooted medium can significantly increase the rooting rate, the root length and the fresh weight, promote the activities of superoxide dismutase (SOD); catalase (CAT) and peroxidase (POD) and decrease the production rate of O_2 ·-, the malondialdehyde (MDA) contents and the plasma membrane permeability. There are important theory meaning and practical value in applying LaCl_3 in the rooting medium to raise the rate of rooting and transplant for stone fruit tree.
基金Supported by the National Key Research and Development Program(2018YFD1000903)。
文摘To understand the response characteristics of soybean seedling resistance systems to high-temperature stress,the spring soybean varieties HN44 and HN65 were selected in this study as the experimental materials,as they had substantial differences in stress resistance.Soybean physiological status was studied under high-temperature stress.Sand culture was used in the experiment,and soybeans at the seedling stage were treated with high-temperature stress.The results showed that the activity of antioxidases and osmotic regulatory substance contents in soybean increased under high-temperature treatment for a certain period of time,the activity of antioxidases and osmotic regulatory substance contents decreased after continuous treatment,and high temperatures continuously increased malondialdehyde contents in the two varieties.At high temperatures,the antioxidant activity and osmotic regulator contents of HN44 were higher than those of HN65,and the malondialdehyde contents of HN44 were higher than those of HN65.The above results showed that HN44 soybeans exhibited significantly higher resistance to high-temperature stress than HN65 variety.
基金Supported by Science and Technology Development Planning Project of Henan Province(182102110305)
文摘Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growth rate,dry weight,fresh weight and relative water content of the plants were determined. After 6h of treatment,the activity and gene expression of three antioxidant enzymes,superoxide dismutase( SOD),catalase( CAT) and ascorbate peroxidase( APX) in plants,were measured. The results showed that the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in collard seedlings were higher in the treatment of salt stress with the addition of 0. 05 mmol/L exogenous H_2O_2 than in the simple salt stress treatment; and when endogenous H_2O_2 was removed,the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in plant seedlings were lower than those under simple salt stress. It is speculated that under salt stress,H_2O_2 is involved in the regulation of antioxidant defense gene expression,and it might be an important regulator of salt-induced antioxidant system in collard leaves.