scholarly journals Stress hardening under long-term cadmium treatment is correlated with the activation of antioxidative defence and iron acquisition of chloroplasts in Populus

2016 ◽  
Vol 71 (9-10) ◽  
pp. 323-334 ◽  
Author(s):  
Ádám Solti ◽  
Éva Sárvári ◽  
Erzsébet Szöllősi ◽  
Brigitta Tóth ◽  
Ilona Mészáros ◽  
...  

Abstract Cadmium (Cd), a highly toxic heavy metal affects growth and metabolic pathways in plants, including photosynthesis. Though Cd is a transition metal with no redox capacity, it generates reactive oxygen species (ROS) indirectly and causes oxidative stress. Nevertheless, the mechanisms involved in long-term Cd tolerance of poplar, candidate for Cd phytoremediation, are not well known. Hydroponically cultured poplar (Populus jacquemontiana var. glauca cv. ‘Kopeczkii’) plants were treated with 10 μM Cd for 4 weeks. Following a period of functional decline, the plants performed acclimation to the Cd induced oxidative stress as indicated by the decreased leaf malondialdehyde (MDA) content and the recovery of most photosynthetic parameters. The increased activity of peroxidases (PODs) could have a great impact on the elimination of hydrogen peroxide, and thus the recovery of photosynthesis, while the function of superoxide dismutase (SOD) isoforms seemed to be less important. Re-distribution of the iron content of leaf mesophyll cells into the chloroplasts contributed to the biosynthesis of the photosynthetic apparatus and some antioxidative enzymes. The delayed increase in photosynthetic activity in relation to the decline in the level of lipid peroxidation indicates that elimination of oxidative stress damage by acclimation mechanisms is required for the restoration of the photosynthetic apparatus during long-term Cd treatment.

Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 155
Author(s):  
Anastasia Giannakoula ◽  
Ioannis Therios ◽  
Christos Chatzissavvidis

Photosynthetic changes and antioxidant activity to oxidative stress were evaluated in sour orange (Citrus aurantium L.) leaves subjected to lead (Pb), copper (Cu) and also Pb + Cu toxicity treatments, in order to elucidate the mechanisms involved in heavy metal tolerance. The simultaneous effect of Pb− and Cu on growth, concentration of malondialdehyde (MDA), hydrogen peroxide (H2O2), chlorophylls, flavonoids, carotenoids, phenolics, chlorophyll fluorescence and photosynthetic parameters were examined in leaves of Citrus aurantium L. plants. Exogenous application of Pb and Cu resulted in an increase in leaf H2O2 and lipid peroxidation (MDA). Toxicity symptoms of both Pb and Cu treated plants were stunted growth and decreased pigments concentration. Furthermore, photosynthetic activity of treated plants exhibited a significant decline. The inhibition of growth in Pb and Cu-treated plants was accompanied by oxidative stress, as indicated by the enhanced lipid peroxidation and the high H2O2 concentration. Furthermore, antioxidants in citrus plants after exposure to high Pb and Cu concentrations were significantly increased compared to control and low Pb and Cu treatments. In conclusion, this study indicates that Pb and Cu promote lipid peroxidation, disrupt membrane integrity, reduces growth and photosynthesis and inhibit mineral nutrition. Considering the potential for adverse human health effects associated with high concentrations of Pb and Cu contained in edible parts of citrus plants the study signals that it is important to conduct further research into the accessibility and uptake of the tested heavy metals in the soil and whether they pose risks to humans.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Anna Malgorzata Papinska ◽  
Kathleen Elizabeth Rodgers

Aims. The goal of this study was to evaluate the effects of long-term (16 weeks) administration of angiotensin (1–7) [A(1–7)] on kidney function in db/db mice and to identify the protective mechanisms of this therapy. Methods. db/db mice and heterozygous controls were treated with A(1–7) or vehicle daily, subcutaneously for up to 16 weeks. Kidney injury was assessed by measuring blood flow in renal arteries, plasma creatinine levels, and proteinuria. Effects of treatment on oxidative stress were evaluated by histological staining and gene expression. Results. 16 weeks of daily administration of A(1–7) to a mouse model of severe type 2 diabetes (db/db) prevented the progression of kidney damage. Treatment with A(1–7) improved blood flow in the renal arteries, as well as decreased plasma creatinine levels and proteinuria in diabetic mice. Reduction of oxidative stress was identified as one of the mechanisms of the renoprotective action of A(1–7). Treatment prevented formation of nitrotyrosine residues, a marker of oxidative stress damage. A(1–7) also reduced the expression of two enzymes involved in formation of nitrotyrosine, namely, eNOS and NOX-4. A(1–7) regulated the phosphorylation pattern of eNOS to enhance production of NO in diabetic animals, possibly through the Akt pathway. However, these elevated levels of NO did not result in increased nitrosylation, possibly due to reduced NOX-4 levels. Conclusions. Long-term administration of A(1–7) improved kidney function and reduced oxidative stress damage in db/db mice.


2020 ◽  
Vol 19 (5) ◽  
pp. 336
Author(s):  
Luiza Minato Sagrillo ◽  
Viviane Nogueira De Zorzi ◽  
Luiz Fernando Freire Royes ◽  
Michele Rechia Fighera ◽  
Beatriz Da Silva Rosa Bonadiman ◽  
...  

Physical exercise has been shown to be an important modulator of the antioxidant system and neuroprotective in several diseases and treatments that affect the central nervous system. In this sense, the present study aimed to evaluate the effect of physical exercise in dynamic balance, motor coordination, exploratory locomotor activity and in the oxidative and immunological balance of rats treated with vincristine (VCR). For that, 40 adult rats were divided into two groups: exercise group (6 weeks of swimming, 1h/day, 5 days/week, with overload of 5% of body weight) and sedentary group. After training, rats were treated with 0.5 mg/kg of vincristine sulfate for two weeks or with the same dose of 0.9% NaCl. The behavioral tests were conducted 1 and 7 days after each dose of VCR. On day 15 we carried out the biochemical analyzes of the cerebellum. The physical exercise was able to protect against the loss of dynamic balance and motor coordination and, had effect per se in the exploratory locomotor activity, and neutralize oxidative stress, damage DNA and immune damage caused by VCR up to 15 days after the end of the training protocol. In conclusion, we observed that previous physical training protects of the damage motor induced by vincristine.Key-words: exercise, oxidative stress, neuroprotection, cerebellum.


2012 ◽  
Vol 6 (2) ◽  
pp. 120-123 ◽  
Author(s):  
Oliver Gamondi ◽  
Sebastian Chapela ◽  
Ines Nievas ◽  
Isabel Burgos ◽  
Manuel Alonso ◽  
...  

2020 ◽  
Vol 10 (5) ◽  
pp. 578-586
Author(s):  
Areeg M. Abdelrazek ◽  
Shimaa A. Haredy

Background: Busulfan (Bu) is an anticancer drug with a variety of adverse effects for cancer patients. Oxidative stress has been considered as a common pathological mechanism and it has a key role in the initiation and progression of liver injury by Bu. Aim: The study aimed to evaluate the antioxidant impact of L-Carnitine and Coenzyme Q10 and their protective role against oxidative stress damage in liver tissues. Methods and Material: Thirty-six albino rats were divided equally into six groups. G1 (con), received I.P. injection of DMSO plus 1 ml of distilled water daily by oral gavages; G2 (Bu), received I.P. injection of Bu plus 1 ml of the distilled water daily; G3 (L-Car), received 1 ml of L-Car orally; G4 (Bu + L-Car) received I.P. injection of Bu plus 1 ml of L-Car, G5 (CoQ10) 1 ml of CoQ10 daily; and G6 (Bu + CoQ10) received I.P. injection of Bu plus 1 ml of CoQ10 daily. Results: The recent data showed that Bu induced significant (P<0.05) elevation in serum ALT, AST, liver GSSG, NO, MDA and 8-OHDG, while showing significant (P<0.05) decrease in liver GSH and ATP. On the other hand, L-Carnitine and Coenzyme Q10 ameliorated the negative effects prompted by Bu. Immunohistochemical expression of caspase-3 in liver tissues reported pathological alterations in Bu group while also showed significant recovery in L-Car more than CoQ10. Conclusion: L-Car, as well as CoQ10, can enhance the hepatotoxic effects of Bu by promoting energy production in oxidative phosphorylation process and by scavenging the free radicals.


Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 36
Author(s):  
Francisca Félix ◽  
Catarina C. V. Oliveira ◽  
Elsa Cabrita

In recent years, the effects of novel antioxidants have played an important role in the research focusing on fish cell protection. As food demand grows, aquaculture production becomes more intensive, and fish are more exposed to oxidative stress conditions, like high densities, temperature shifting, frequent fish handling and samplings, and prophylactic or disease treatments, which expose fish to a different environment. Particularly in reproduction, germ cells lose antioxidant capacity with spermatogenesis, as spermatozoa are more prone to oxidative stress. Antioxidants have been used in a variety of fish physiological problems including in reproduction and in the establishment of cryopreservation protocols. From the most used antioxidants to natural plant food and herbs, and endogenously produced antioxidants, like melatonin, a review of the literature available in terms of their effects on the protection of fish spermatozoa is presented here in a classified structure. Several direct and indirect approaches to improve gamete quality using antioxidants administration are mentioned (through feed supplementation or by adding in cryopreservation media), as well as factors affecting the efficiency of these molecules and their mechanisms of action. Special attention is given to the unclear melatonin pathway and its potential scavenger activity to prevent and counteract oxidative stress damage on fish spermatozoa.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Chan Mi Park ◽  
Wonsock Kim ◽  
Hye Chang Rhim ◽  
Eun Sik Lee ◽  
Jong Hun Kim ◽  
...  

Abstract Background Pneumonia is a major cause of morbidity and mortality in older adults. The role of frailty assessment in older adults with pneumonia is not well defined. Our purpose of the study was to investigate 30-day clinical course and functional outcomes of pneumonia in older adults with different levels of frailty. Methods A prospective cohort was conducted at a university hospital in Seoul, Korea with 176 patients who were 65 years or older and hospitalized with pneumonia. A 50-item deficit-accumulation frailty index (FI) (range: 0–1; robust < 0.15, pre-frail 0.15–0.24, mild-to-moderately frail 0.25–0.44, and severely frail ≥ 0.45) and the pneumonia severity CURB-65 score (range: 0–5) were measured. Primary outcome was death or functional decline, defined as worsening dependencies in 21 daily activities and physical tasks in 30 days. Secondary outcomes were intensive care unit admission, psychoactive drug use, nasogastric tube feeding, prolonged hospitalization (length of stay > 15 days), and discharge to a long-term care institution. Results The population had a median age 79 (interquartile range, 75–84) years, 68 (38.6 %) female, and 45 (25.5 %) robust, 36 (47.4 %) pre-frail, 37 (21.0 %) mild-to-moderately frail, and 58 (33.0 %) severely frail patients. After adjusting for age, sex, and CURB-65, the risk of primary outcome for increasing frailty categories was 46.7 %, 61.1 %, 83.8 %, and 86.2 %, respectively (p = 0.014). The risk was higher in patients with frailty (FI ≥ 0.25) than without (FI < 0.25) among those with CURB-65 0–2 points (75 % vs. 52 %; p = 0.022) and among those with CURB-65 3–5 points (93 % vs. 65 %; p = 0.007). In addition, patients with greater frailty were more likely to require nasogastric tube feeding (robust vs. severe frailty: 13.9 % vs. 60.3 %) and prolonged hospitalization (18.2 % vs. 50.9 %) and discharge to a long-term care institution (4.4 % vs. 59.3 %) (p < 0.05 for all). Rates of intensive care unit admission and psychoactive drug use were similar. Conclusions Older adults with frailty experience high rates of death or functional decline in 30 days of pneumonia hospitalization, regardless of the pneumonia severity. These results underscore the importance of frailty assessment in the acute care setting.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bailey Hiles-Murison ◽  
Andrew P. Lavender ◽  
Mark J. Hackett ◽  
Joshua J. Armstrong ◽  
Michael Nesbit ◽  
...  

AbstractRepeated sub-concussive impact (e.g. soccer ball heading), a significantly lighter form of mild traumatic brain injury, is increasingly suggested to cumulatively alter brain structure and compromise neurobehavioural function in the long-term. However, the underlying mechanisms whereby repeated long-term sub-concussion induces cerebral structural and neurobehavioural changes are currently unknown. Here, we utilised an established rat model to investigate the effects of repeated sub-concussion on size of lateral ventricles, cerebrovascular blood–brain barrier (BBB) integrity, neuroinflammation, oxidative stress, and biochemical distribution. Following repeated sub-concussion 3 days per week for 2 weeks, the rats showed significantly enlarged lateral ventricles compared with the rats receiving sham-only procedure. The sub-concussive rats also presented significant BBB dysfunction in the cerebral cortex and hippocampal formation, whilst neuromotor function assessed by beamwalk and rotarod tests were comparable to the sham rats. Immunofluorescent and spectroscopic microscopy analyses revealed no significant changes in neuroinflammation, oxidative stress, lipid distribution or protein aggregation, within the hippocampus and cortex. These data collectively indicate that repeated sub-concussion for 2 weeks induce significant ventriculomegaly and BBB disruption, preceding neuromotor deficits.


Sign in / Sign up

Export Citation Format

Share Document