scholarly journals Mechanism for Higher Tolerance to and Lower Accumulation of Arsenite in NtCyc07-Overexpressing Tobacco

Plants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1480
Author(s):  
DongGwan Kim ◽  
Ramin Bahmani ◽  
Mahsa Modareszadeh ◽  
Seongbin Hwang

Arsenite [As(III)] is a highly toxic chemical to all organisms. Previously, we reported that the overexpression of NtCyc07 enhanced As(III) tolerance and reduced As(III) accumulation in yeast (Saccharomyces cerevisiae) and tobacco (Nicotiana tabacum). To understand a mechanism for higher As(III) tolerance and lower As(III) accumulation in NtCyc07-overexpressing tobacco, we examined the expression levels of various putative As(III) transporters (aquaporin). The expressions of putative As(III) exporter NIP1;1, PIP1;1, 1;5, 2;1, 2;2, and 2;7 were enhanced, while the expressions of putative As(III) importer NIP3;1, 4;1, and XIP2;1 were decreased, contributing to the reduced accumulation of As(III) in NtCyc07-overexpressing tobacco. In addition, the levels of oxidative stress indicators (H2O2, superoxide and malondialdehyde) were lower, and the activities of antioxidant enzymes (catalase, superoxide dismutase and glutathione reductase) were higher in NtCyc07-tobacco than in the control tobacco. This suggests that the lower oxidative stress in transgenic tobacco may be attributed to the higher activities of antioxidant enzymes and lower As(III) levels. Taken together, the overexpression of NtCyc07 enhances As(III) tolerance by reducing As(III) accumulation through modulation of expressions of putative As(III) transporters in tobacco.

2020 ◽  
Vol 63 (7) ◽  
pp. 99-105
Author(s):  
Viktor V. Ivanishchev ◽  

We studied alterations in oxidative stress indicators (hydrogen peroxide, superoxide radical, lipid peroxidation – LPO) and alterations in the activity of antioxidant enzymes (catalase, ascorbate peroxidase, guaiacol peroxidase, glutathione reductase) in triticale shoots (Triticosecale) during short-term (0-96 h) sodium chloride stress (120 mM) with statistical methods: principal component analysis (PCA) and cluster analysis. Analysis of alterations in the activity of enzymes with the PCA method does not allow them to be unambiguously included in a single group, despite the fact that they all belong to antioxidant enzymes. The inclusion of oxidative stress indicators in this analysis did not make the picture simpler. Using the cluster analysis method, it can be concluded that under conditions of short-term chloride stress in the shoots of triticale, much more catalase (than other enzymes studied) is associated with the protection of membranes from lipid peroxidation than with the utilization of hydrogen peroxide. This is also reflected by the highest correlation coefficients: catalase – LPO (0.94), catalase – hydrogen peroxide (0.79). The formation of primary clusters between ascorbate peroxidase and glutathione reductase reflect the significance of the association of the ascorbate – glutathione cycle with the processes of utilization of reactive oxygen species (primarily hydrogen peroxide) under experimental conditions. It was also shown that under conditions of short-term chloride stress in the shoots of triticale, guaiacol peroxidase plays the least role in the utilization of hydrogen peroxide. In this case, salt ions again form a single primary cluster, which combines with other clusters at the maximum Euclidean distance in the experiment.


2022 ◽  
Vol 46 (1) ◽  
Author(s):  
Patrick Chukwuyenum Ichipi-Ifukor ◽  
Samuel Ogheneovo Asagba ◽  
Chibueze Nwose ◽  
Joseph Chukwufumnanya Mordi ◽  
John Chukwuma Oyem

Abstract Background The probable mechanism of an earlier reported capacity of palm oil extracts to confer protection against high dose cadmium poisoning in rats was reported in this study. Similar experimental design earlier reported by us was retained. Rats therefore were sacrificed at intervals of twelve; twenty four and forty eight hours post CdCl2 insult. Results Oxidative stress and antioxidant status (malondialdehyde, superoxide dismutase, catalase and glutathione) were assessed in tissues (liver, kidney, heart, brain, muscle) and serum. Oxidative stress indicators showed a significantly (p < 0.05) increased lipid peroxidation and alterations in antioxidant defence systems occasioned by drop in catalase and superoxide dismutase enzymes (serum, liver, heart, brain and kidneys) of the rats. Also observed were significant (p < 0.05) reduction in the non-enzymatic antioxidant reduced glutathione over time. Pre-administration of rats with the crude palm oil and its extracts modulated cadmium mediated depletion of the antioxidant capacities of rats acutely exposed to cadmium and rising lipid peroxidation profile. Conclusions Regulation of stress and antioxidant response was the underlying mechanism by which the extracts conferred protection against high dose cadmium insult thus suggesting its potential as a viable therapeutic target against its deleterious effects. Graphical Abstract


2019 ◽  
Vol 48 (3) ◽  
pp. 270-278
Author(s):  
Hediye Elif Kiliç ◽  
Hatice Tunca ◽  
Tuğba Ongun Sevindik ◽  
Ali Doğru

Abstract This study explores the activity of total superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR), biomass accumulation and chlorophyll a content in Scenedesmus ellipsoideus Chodat grown under conditions of varying zinc (Zn) concentrations. In addition, the activity of different SOD isozymes (MnSOD, FeSOD and CuZnSOD) was measured separately to determine the intracellular extent of oxidative stress resulting from Zn toxicity. We found that the activity of FeSOD and MnSOD was induced by lower Zn concentration (2 μg ml−1 and 4 μg ml−1, respectively), whereas CuZnSOD activity was not affected, which indicates that chloroplasts are the first location in S. ellipsoideus cells where superoxide accumulation is accelerated by Zn toxicity. The activity of total SOD and APX was significantly increased by moderate Zn concentrations, probably due to some oxidative stress caused by Zn toxicity. The higher level of Zn application, however, led not only to the inhibition of total SOD and APX activity, but also to the reduction of biomass accumulation and chlorophyll a content. As a result, it can be concluded that the accumulation of superoxide radicals and H2O2 in S. ellipsoideus cells induced by Zn toxicity may be responsible for the reduced growth rate and the impairment of photosynthetic pigments.


2021 ◽  
Author(s):  
Patrick Chukwuyenum ICHIPI-IFUKOR ◽  
Samuel Ogheneovo ASAGBA ◽  
Chibueze NWOSE ◽  
Joseph Chukwufumnanya MORDI ◽  
John Chukwuma OYEM

Abstract Background: The probable mechanism of an earlier reported capacity of palm oil extracts to confer protection against high dose cadmium poisoning in rats was reported in this study. Similar experimental design earlier reported by us was retained. Rats therefore were sacrificed at intervals of twelve; twenty four and forty eight hours post CdCl2 insult. Results: Oxidative stress and antioxidant status (malondialdehyde, superoxide dismutase, catalase and glutathione) were assessed in tissues (liver, kidney, heart, brain, muscle) and serum. Oxidative stress indicators showed a significantly (p<0.05) increased lipid peroxidation and alterations in antioxidant defence systems occasioned by drop in catalase and superoxide dismutase enzymes (serum, liver, heart, brain and kidneys) of the rats. Also observed were significant (p<0.05) reduction in the non-enzymatic antioxidant reduced glutathione over time. Pre-administration of rats with the crude palm oil and its extracts modulated cadmium mediated depletion of the antioxidant capacities of rats acutely exposed to cadmium and rising lipid peroxidation profile. Conclusions: Regulation of stress and antioxidant response was the underlying mechanism by which the extracts conferred protection against high dose cadmium insult thus suggesting its potential as a viable therapeutic target against its deleterious effects.


Author(s):  
Alireza Mortazavi ◽  
Hossein Mohammad Pour Kargar ◽  
Farimah Beheshti ◽  
Akbar Anaeigoudari ◽  
Gholamhasan Vaezi ◽  
...  

Abstract. The effect of carvacrol (CAR) on oxidative stress, inflammation, and liver dysfunction induced by lipopolysaccharide (LPS) was explored. The rats (n=40) were daily injected (2 weeks) by saline as control, LPS (1 mg/kg, i.p.), and 25, 50 or 100 mg/kg CAR (i.p.) before LPS. LPS increased aspartate transaminase (AST: 162±13 U/L), alanine aminotransferase (ALT: 74.6±2.15 U/L), alkaline phosphatase (ALK-P: 811±51 U/L), interlukine-1β (IL-1β: 1254±51 pg/g tissue), malondialdehyde (MDA: 32±1.09 nM/g tissue), and nitric oxide (NO: 224±13.5 nM/g tissue) (P<0.01–P<0.001) while, decreased total protein(4.08±0.38 g/dl), albumin(2.79±0.16 g/dl), thiol (5.16±0.19 μM/g tissue), superoxide dismutase (SOD: 10.57±0.13 U/g tissue), and catalase (CAT: 0.78±0.02 U/g tissue) compared to control (P<0.001). CAR reversed the effects of LPS (P<0.05–P<0.001). In the rats treated by 100 mg/kg CAR, the indicators were as follows: AST: 118±10.1 U/L, ALT: 42.5±4.13 U/L, ALK-P: 597±39.91 U/L, IL-1β: 494±15 pg/g tissue, and NO: 141±5.35 nM/g tissue. Both 50 and 100 mg/kg CAR corrected oxidative stress indicators and in the group treated by 100 mg/kg CAR, they were: MDA: 23.4±0.91 nM/g tissue, thiol: 7.98±0.18 μM/g tissue, SOD: 21±0.8 U/g tissue, and CAT: 1.12±0.02 U/g tissue(P<0.05–P<0.001). In conclusion, CAR improved liver function, accompanied with antioxidant and antiinflammatory effects.


2017 ◽  
Vol 68 (6) ◽  
pp. 1381-1383
Author(s):  
Allia Sindilar ◽  
Carmen Lacramioara Zamfir ◽  
Eusebiu Viorel Sindilar ◽  
Alin Constantin Pinzariu ◽  
Eduard Crauciuc ◽  
...  

Endometriosis is described as a gynecological disorder characterized by the presence of endometrial tissue outside the uterus; extensively explored because of its increasing incidency, with an indubitable diagnostic only after invasive surgery, with no efficient treatment, it has still many aspects to be elucidated. A growing body of facts sustain oxidative stress as a crucial factor between the numerous incriminated factors implicated in endometriosis ethiopathogeny. Reactive oxygen species(ROS) act to decline reproductive function. Our study intends to determine if an experimental model of endometriosis may be useful to assess the impact of oxidative stress on endometrial cells; we have used a murine model of 18 adult Wistar female rats. A fragment from their left uterine horn was implanted in the abdominal wall. After 4 weeks, a laparatomy was performed, 5 endometrial implants were removed, followed by biochemical tissue assay of superoxide dismutase(SOD) and catalase(CAT). At the end of the experiment, the rats were sacrificed, the implants were removed for histopathological exam and biochemical assay of antioxidant enzymes. The results revealed decreased levels of antioxidant enzymes, pointing on significant oxidative stress involvement.


2020 ◽  
Vol 70 (2) ◽  
pp. 227-237
Author(s):  
Eda Güneş

Abstract The aim of the this study was to evaluate the effects of fresh, dried and freeze-dried Centaurea depressa M. Bieb. (Asteraceae) on the oxidant and antioxidant status of the model organism D. melanogaster Meigen (Diptera: Drosophilidae) experimentally. The study was carried out from 2016 to 2019, and plant leaf extracts (0-50 mg/l) were added to insect standard artificial diets. The total protein, protein carbonyl content and glutathione-S-transferase, superoxide dismutase and catalase activities were quantified at the insect’s third larval stage. Our data showed that protein carbonyl content varied from 2.70 nmol/mg protein in the control group to 59.11 nmol/mg protein in the group fed with fresh leaf extract signifying induction of oxidative stress. All extracts increased the levels of all antioxidant enzymes and decreased the amounts of total protein. Meanwhile, the group fed with the freeze-dried extract showed no significant difference in the levels of total protein and protein carbonyl content except at the 50 mg/l concentration of the extract. Moreover, this group had superoxide dismutase and catalase activities 4 to 5 times higher than in the control group. In conclusion, induction of oxidative stress indicates that the fresh form of C. depressa leaves may have potential as a natural pesticide, whereas induction of endogenous antioxidant enzymes by the freeze-dried extract suggest its potential as an antioxidant.


Zygote ◽  
2019 ◽  
Vol 27 (6) ◽  
pp. 432-435
Author(s):  
Thais Rose dos Santos Hamilton ◽  
Gabriela Esteves Duarte ◽  
José Antonio Visintin ◽  
Mayra Elena Ortiz D’Ávila Assumpção

SummaryLong-term heat stress (HS) induced by testicular insulation generates oxidative stress (OS) on the testicular environment; consequently activating antioxidant enzymes such as superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx). The aim of this work was to immunolocalize antioxidant enzymes present in different cells within the seminiferous tubule when rams were submitted to HS. Rams were divided into control (n = 6) and treated group (n = 6), comprising rams subjected to testicular insulation for 240 h. After the testicular insulation period, rams were subjected to orchiectomy. Testicular fragments were submitted to immunohistochemistry for staining against SOD, GR and GPx enzymes. We observed immunolocalization of GPx in more cell types of the testis after HS and when compared with other enzymes. In conclusion, GPx is the main antioxidant enzyme identified in testicular cells in an attempt to maintain oxidative balance when HS occurs.


2012 ◽  
Vol 63 (10) ◽  
pp. 3631-3642 ◽  
Author(s):  
G. Roqueiro ◽  
S. Maldonado ◽  
M. d. C. Rios ◽  
H. Maroder

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