scholarly journals Fer-Mediated Cortactin Phosphorylation Is Associated with Efficient Fibroblast Migration and Is Dependent on Reactive Oxygen Species Generation during Integrin-Mediated Cell Adhesion

2007 ◽  
Vol 27 (17) ◽  
pp. 6140-6152 ◽  
Author(s):  
Waheed Sangrar ◽  
Yan Gao ◽  
Michelle Scott ◽  
Peter Truesdell ◽  
Peter A. Greer
Keyword(s):  
Reactive Oxygen Species ◽  
Tyrosine Phosphorylation ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Actin Binding ◽  
Integrin Signaling ◽  
Oxygen Species ◽  
Fibroblast Migration ◽  
Diphenylene Iodonium ◽  
First Time

ABSTRACT The molecular details linking integrin engagement to downstream cortactin (Ctn) tyrosine phosphorylation are largely unknown. In this report, we show for the first time that Fer and Ctn are potently tyrosine phosphorylated in response to hydrogen peroxide (H2O2) in a variety of cell types. Working with catalytically inactive fer and src/yes/fyn-deficient murine embryonic fibroblasts (fer DR/DR and syf MEF, respectively), we observed that H2O2-induced Ctn tyrosine phosphorylation is primarily dependent on Fer but not Src family kinase (SFK) activity. We also demonstrated for the first time that Fer is activated by fibronectin engagement and, in concert with SFKs, mediates Ctn tyrosine phosphorylation in integrin signaling pathways. Reactive oxygen species (ROS) scavengers or the NADPH oxidase inhibitor, diphenylene iodonium, attenuated integrin-induced Fer and Ctn tyrosine phosphorylation. Taken together, these findings provide novel genetic evidence that a ROS-Fer signaling arm contributes to SFK-mediated Ctn tyrosine phosphorylation in integrin signaling. Lastly, a migration defect in fer DR/DR MEF suggests that integrin signaling through the ROS-Fer-Ctn signaling arm may be linked to mechanisms governing cell motility. These data demonstrate for the first time an oxidative link between integrin adhesion and an actin-binding protein involved in actin polymerization.

scholarly journals The effect of acrylamide on sperm oxidative stress, total antioxidant levels, tyrosine phosphorylation, and carboxymethyl-lysine expression: A laboratory study

2021 ◽  
Author(s):  
Mojdeh Hosseinpoor Kashani ◽  
Mina Ramezani ◽  
Zeinab Piravar
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Superoxide Dismutase ◽  
Tyrosine Phosphorylation ◽  
Laboratory Study ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Total Antioxidant ◽  
Carboxymethyl Lysine

Background: Acrylamide (AA) is a reactive molecule produced during food processing at temperatures above 120°C. Objective: To evaluate the impact of different concentrations of AA on human sperm parameters, oxidative stress and total antioxidant capacity (TAC). Materials and Methods: In this laboratory study, semen samples were obtained from healthy donors referred to the Taleghani Hospital, Tehran, Iran between June and July 2019. Samples were divided into four groups (n = 10/each): one control and three treatment groups (0.5, 1, and 2 mM of AA). After 2 hr of exposure to AA, the superoxide dismutase and malondialdehyde levels were measured based on colorimetric methods. The TAC was determined by the ferric-reducing antioxidant power assay. Flow cytometry was performed to measure the intracellular reactive oxygen species generation. Also, immunohistochemistry was done to determine the effect of AA on tyrosine phosphorylation and carboxymethyl-lysine expression. Results: Results of the study demonstrated that the motility and viability of spermatozoa were significantly decreased after AA exposure (p < 0.001). This decrease was also seen in the TAC and superoxide dismutase activity as well as in the phosphotyrosine percentage compared with the control (p < 0.01). However, the carboxymethyllysine and prooxidant activity including reactive oxygen species generation and lipid peroxidation level increased (p < 0.001). Conclusion: Overall, the results confirmed the detrimental effect of AA on human spermatozoa which may be due to oxidative stress and decreased total antioxidant levels. AA may reduce fertility by reducing sperm capacitation and motility. Key words: Acrylamide, Oxidative stress, Antioxidant, Spermatozoa, Infertility.

Redox regulation of tyrosine phosphorylation in human spermatozoa and its role in the control of human sperm function

1995 ◽  
Vol 108 (5) ◽  
pp. 2017-2025 ◽  
Author(s):  
R.J. Aitken ◽  
M. Paterson ◽  
H. Fisher ◽  
D.W. Buckingham ◽  
M. van Duin
Keyword(s):  
Reactive Oxygen Species ◽  
Tyrosine Phosphorylation ◽  
Redox Regulation ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Human Sperm ◽  
Human Spermatozoa ◽  
Sperm Function ◽  
Ionophore A23187 ◽  
Oxygen Species

The redox status of human spermatozoa was found to have a profound influence on the fertilizing potential of these cells in association with qualitative and quantitative changes in the patterns of tyrosine phosphorylation. In general, oxidizing conditions enhanced tyrosine phosphorylation and stimulated sperm function, whereas reducing conditions had the opposite effect. Unstimulated human spermatozoa exhibited low levels of spontaneous acrosomal exocytosis and sperm-oocyte fusion and minimal reactive oxygen species generation, while phosphotyrosine expression was largely confined to a single protein of 116 kDa. However, if the spermatozoa were exposed to oxidizing conditions through the addition of exogenous H2O2, or the stimulation of endogenous NADPH-dependent reactive oxygen species generation, then a dramatic increase in tyrosine phosphorylation was observed (major phosphotyrosyl bands at 222 kDa, 200 kDa, 159 kDa, 133 kDa, 116 kDa and 82 kDa) in concert with the functional activation of the spermatozoa. A causal association between reactive oxygen species generation, tyrosine phosphorylation and sperm function was indicated by studies with the ionophore, A23187, which induced high rates of spermoocyte fusion together with enhanced rates of reactive oxygen species production and the increased expression of phosphotyrosyl proteins. This functional response to A23187 could be abrogated, without any concomitant change in sperm motility or viability, by using membrane permeant thiols or catalase to suppress the reactive oxygen species-induced increase in phosphotyrosine expression. The fact that the biological responses of human spermatozoa to biological agonists (recombinant human ZP3 and progesterone) could also be inhibited by catalase indicated the general relevance of these findings.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Inhibitory Effects of Antioxidant Reagent in Reactive Oxygen Species Generation and Penetration of Appressoria of Alternaria alternata Japanese Pear Pathotype

2010 ◽  
Vol 100 (9) ◽  
pp. 840-847 ◽  
Author(s):  
Gang-Su Hyon ◽  
Ken-ichi Ikeda ◽  
Naoki Hosogi ◽  
Takeshi Shinogi ◽  
Pyoyun Park
Keyword(s):  
Reactive Oxygen Species ◽  
Ascorbic Acid ◽  
Nadph Oxidase ◽  
Alternaria Alternata ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Japanese Pear ◽  
Oxygen Species ◽  
Inhibitory Effects ◽  
Diphenylene Iodonium

In the Japanese pear pathotype of Alternaria alternata, H2O2 is generated solely from penetration pegs and not from other portions of subcuticular hyphae within the pectin layers of host leaves. A close association between H2O2 generation and fungal aggressiveness is expected because the pegs are important for fungal penetration into the host epidermis. To determine the potential role of reactive oxygen species in microbial pathogenicity, we studied the inhibitory effects of the antioxidant reagent ascorbic acid and the NADPH oxidase inhibitor diphenylene iodonium on infection of the pathogen. In our study, we showed H2O2 generation to be inhibited by inoculation with the mixture of ascorbic acid or diphenylene iodonium and spores at the pegs in the spore-inoculated host leaves. The decrease of generation in the pegs resulted in penetration failure, indicating that H2O2 generation probably contributed to strengthening of the penetration and probably was recruited by NADPH oxidase.

Роль оксида азота в реализации антиоксидантного эффекта неопиатного аналога лей-энкефалина в сердце новорожденных белых крыс

2019 ◽  
pp. 61-64
Keyword(s):  
Reactive Oxygen Species ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Postnatal Period ◽  
Oxide System ◽  
No Synthase ◽  
Albino Rats ◽  
Oxygen Species ◽  
Control Parameters ◽  
Synthase Inhibitor

The eff ect of the non-opiate analog of leu-enkephalin (peptide NALE: Phe – D – Ala – Gly – Phe – Leu – Arg) on the reactive oxygen species generation in the heart of albino rats in the early postnatal period was studied. Peptide NALE was administered intraperitoneally in the dose of 100 μ/kg daily from 2 to 6 days of life. Reactive oxygen species generation was assessed by chemiluminescence in the heart homogenates of 7-day-old animals. Decreasing of reactive oxygen species generation nearly by 30 % and an increasing in antioxidant system activity by the 20-27 %, compared with the control parameters, were found. The antioxidant eff ect of peptide NALE is associated with the presence of the amino acid Arg in the structure of the peptide. An analogue of NALE peptide, devoid of Arg (peptide Phe – D – Ala – Gly – Phe – Leu – Gly), had a signifi cant lower antioxidant eff ect. The NO-synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) in the dose 50 mg/kg, administered with NALE peptide, reduced the severity of the NALE antioxidant eff ect. The results of the study suggest that the pronounced antioxidant eff ect of NALE peptide in the heart of albino rats, at least in part, is due to the interaction with the nitric oxide system.

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