MP60-03 THE IMPACT OF INTRAVESICAL LIPOSOME-BASED NGF ANTISENSE THERAPY ON BLADDER OVERACTIVITY AND NOCICEPTION IN A RAT MODEL OF CYSTITIS INDUCED BY HYDROGEN PEROXIDE

Gonadotropin-releasing hormone (GnRH) stimulation of its eponymous receptor on the surface of endocrine anterior pituitary gonadotrope cells (gonadotropes) initiates multiple signaling cascades that culminate in the secretion of luteinizing and follicle-stimulating hormones, which have critical roles in fertility and reproduction. Enhanced luteinizing hormone biosynthesis, a necessary event for ovulation, requires a signaling pathway characterized by calcium influx through L-type calcium channels and subsequent activation of the mitogen-activated protein kinase extracellular signal-regulated kinase (ERK). We previously reported that highly localized subplasmalemmal calcium microdomains produced by L-type calcium channels (calcium sparklets) play an essential part in GnRH-dependent ERK activation. Similar to calcium, reactive oxygen species (ROS) are ubiquitous intracellular signaling molecules whose subcellular localization determines their specificity. To investigate the potential influence of oxidant signaling in gonadotropes, here we examined the impact of ROS generation on L-type calcium channel function. Total internal reflection fluorescence (TIRF) microscopy revealed that GnRH induces spatially restricted sites of ROS generation in gonadotrope-derived αT3-1 cells. Furthermore, GnRH-dependent stimulation of L-type calcium channels required intracellular hydrogen peroxide signaling in these cells and in primary mouse gonadotropes. NADPH oxidase and mitochondrial ROS generation were each necessary for GnRH-mediated stimulation of L-type calcium channels. Congruently, GnRH increased oxidation within subplasmalemmal mitochondria, and L-type calcium channel activity correlated strongly with the presence of adjacent mitochondria. Collectively, our results provide compelling evidence that NADPH oxidase activity and mitochondria-derived hydrogen peroxide signaling play a fundamental role in GnRH-dependent stimulation of L-type calcium channels in anterior pituitary gonadotropes.

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Impact of two disinfectants on detachment of Enterococcus faecalis from polythene in aquatic microcosm

Research in Biotechnology ◽

10.19071/rib.2016.v7.2981 ◽

2016 ◽

Vol 7 (1) ◽

Author(s):

C. Lontsi Djimeli ◽

A. Tamsa Arfao ◽

V Rossi ◽

N Nsulem ◽

V Raspal ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Cell Adhesion ◽

Enterococcus Faecalis ◽

Sodium Hypochlorite ◽

Growth Phases ◽

Planktonic Cells ◽

Stationary Growth ◽

Experimental Conditions ◽

The Impact ◽

Aquatic Microcosm

After cell adhesion processes in microcosm, the impact of sodium hypochlorite (NaOCl) and hydrogen peroxide (H2O2) on the detachment of Enterococcus faecalis from polythene fragments immersed in water under stationary and dynamic conditions was assessed. The abundance of planktonic cells was also evaluated. The density of E. faecalis adhered in absence of disinfectant fluctuated between 2 and 4 units (Log CFU/cm2). After living in disinfected water, the density of E. faecalis remained adhered to polythene sometimes reached 2 units (Log CFU/Cm2). This highest abundance of cells remained adhered was recorded with cells coming from the lag, exponential and stationary growth phases in water treated with 0.5‰ NaOCl. In H2O2 disinfected water, the highest value was recorded at all cells growth phases with 5‰ H2O2 concentration. Adhered E. faecalis cells have been sometimes completely or partially decimated respectively by NaOCl and H2O2 treated water. Considering separately each experimental condition, it was noted that increasing the concentration of disinfectant caused a significant decrease (P≤0.01) in abundance of cells stay adhered after living in water disinfected by the two disinfectants. Changes in disinfectant concentrations in different experimental conditions had an impact on the detachment of E. faecalis cells from the substrates.

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The Effect of Nitrogen Fertilization and Fusarium culmorum Inoculation on the Biomarkers of Oxidative Stress in Wheat Flag Leaves

Poljoprivreda ◽

10.18047/poljo.27.2.2 ◽

2021 ◽

Vol 27 (2) ◽

pp. 15-24

Author(s):

Magdalena Matić ◽

◽

Rosemary Vuković ◽

Karolina Vrandečić ◽

Ivna Štolfa Čamagajevac ◽

...

Keyword(s):

Oxidative Stress ◽

Hydrogen Peroxide ◽

Lipid Peroxidation ◽

Antioxidant Enzymes ◽

Biotic Stress ◽

Flag Leaf ◽

Fusarium Culmorum ◽

Antioxidant Response ◽

The Impact ◽

Biomarkers Of Oxidative Stress

During cultivation, wheat is exposed to several abiotic and/or biotic stress conditions that may adversely impact the wheat yield and quality. The impact of abiotic stress caused by nitrogen deficiency and biotic stress caused by phytopathogenic fungus Fusarium culmorum on biomarkers of oxidative stress in the flag leaf of nine winter wheat varieties (Ficko, U-1, Galloper, BC Mandica, BC Opsesija, Ingenio, Isengrain, Felix, and Bezostaya-1) was analyzed in this study. Hydrogen peroxide concentration and lipid peroxidation level were measured as indicators of oxidative stress, while the antioxidant response was determined by measuring the concentration of phenolic compounds and activities of antioxidant enzymes. Wheat variety and nitrogen treatment had a significant effect on all examined biomarkers of oxidative stress in the flag leaf, while the impact of Fusarium treatment was less pronounced. The most significant impact on the measured stress biomarkers had a low nitrogen level, which mainly increased hydrogen peroxide concentration and lipid peroxidation level and decreased activities of antioxidant enzymes in most varieties. The obtained results were discussed and compared with the previous study in which biochemical analyzes were performed on the wheat spike. There was no significant strong correlation between flag leaf and spike response in the measured parameters, which, in addition to the variety-specific response, also indicates a tissue-specific antioxidant response.

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Emodin alleviates LPS-induced inflammatory response in lung injury rat by affecting the function of neutrophils

10.21203/rs.2.22090/v2 ◽

2020 ◽

Author(s):

Hongxia Mei ◽

Ying Tao ◽

Tianhao Zhang ◽

Feng Qi

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Inflammatory Response ◽

Rat Model ◽

Neutrophil Function ◽

Life Threatening ◽

Pulmonary Inflammatory Response ◽

Anti Inflammatory ◽

Factor Α ◽

The Impact

Abstract Background: Acute lung injury (ALI) and/or acute respiratory distress syndrome (ARDS) are critical life-threatening syndromes characterized by the infiltration of a large number of neutrophils that lead to an excessive inflammatory response. Emodin (Emo) is a naturally occurring anthraquinone derivative and an active ingredient of Chinese medicine. It is believed to have anti-inflammatory effects. In this study, we examined the impact of Emo on the pulmonary inflammatory response and the neutrophil function in a rat model of lipopolysaccharide (LPS)-induced ALI.Results: Treatment with Emo protected rat against LPS-induced ALI. Compared to untreated rat, Emo-treated rat exhibited significantly ameliorated lung pathological changes and decreased tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). However, Emo has no protective effect on the rat model of acute lung injury with neutrophil deficiency. In addition, treatment with Emo enhanced the bactericidal capacity of LPS-induced neutrophils via the up-regulation of the ability of neutrophils to phagocytize bacteria and generate neutrophil extracellular traps (NETs). Emo also downregulated the neutrophil respiratory burst and the expression of reactive oxygen species (ROS) in LPS-stimulated neutrophils, alleviating the damage of neutrophils to surrounding tissues. Finally, Emo can accelerate the resolution of inflammation by promoting apoptosis of neutrophils. Conclusion: Our results provide the evidence that Emo could ameliorates LPS-induced ALI via its anti-inflammatory action by modulating the function of neutrophils. Emo may be a promising preventive and therapeutic agent in the treatment of ALI.

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Experience of measuring glutathione peroxidase activity in surgically induced endometrial-like lesions in rats

Journal of obstetrics and women s diseases ◽

10.17816/jowd52877 ◽

2021 ◽

Vol 70 (2) ◽

pp. 55-61

Author(s):

Aleksey V. Razygraev ◽

Elena V. Baziyan ◽

Lyudmila S. Polyanskikh ◽

Mariya A. Petrosyan

Keyword(s):

Hydrogen Peroxide ◽

Antioxidant Enzymes ◽

Glutathione Peroxidase ◽

Rat Model ◽

Peroxidase Activity ◽

Specific Activity ◽

Reduced Glutathione ◽

Glutathione Peroxidase Activity ◽

Nitrobenzoic Acid ◽

Surgically Induced

BACKGROUND: Endometriosis is known to be linked with altered activities of antioxidant enzymes and with their gene polymorphisms. Progestins are known to induce glutathione peroxidase activity in the endometrium and promote reduction of endometrial lesions. It could be useful to estimate the correlation between the activity of glutathione peroxidase within endometrial lesions and their degree of reduction. AIM: The present study was aimed at estimating glutathione peroxidase activity in surgically induced endometrial-like lesions of different degree of reduction in rat model of endometriosis. MATERIALS AND METHODS: The method for determining glutathione peroxidase activity using hydrogen peroxide as a substrate and 5,5-dithiobis(2-nitrobenzoic acid) for estimation of residual reduced glutathione was applied for quantitative analysis of the enzyme activity in endometriotic foci, surgically induced in female Wistar rats. An assay of glutathione peroxidase activity in tissue homogenates was performed at 37C in a reaction medium containing Tris-HCl buffer supplemented with tetrasodium ethylenediaminetetraacetate and sodium azide (pH 8.5) in the presence of 0.55 mM reduced glutathione and 0.192 mM hydrogen peroxide. Before adding trichloroacetic acid, 40-second incubation was used. The correlation between the specific activity of the enzyme and protein amount in endometriotic foci was estimated. RESULTS: In a rat model of endometriosis, there was a high, well-determined glutathione peroxidase activity in endometriotic foci. For the same endometriotic tissue sample, the enzymatic activity was proportional to the amount of protein in the reaction mixture. The range of specific glutathione peroxidase activity was 2.436.45 micromoles of consumed glutathione per minute per milligram of protein (n = 7). In most reduced endometriotic foci (with the minimum amount of endometriotic tissue), the highest specific activity of glutathione peroxidase was found (the Spearmans rho of 0.93 with p = 0.0067). CONCLUSIONS: The method for determining glutathione peroxidase activity using hydrogen peroxide and 5,5-dithiobis(2-nitrobenzoic acid) is convenient for working with the endometriotic tissue in a rat model of endometriosis. We can accept, with p 0.01, that weight of endometriotic foci is negatively linked with specific glutathione peroxidase activity within their tissue. The results are analogous to the previously obtained data on catalase activity and suggest the involvement of both antioxidant enzymes in reduction of endometrial lesions.

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The Impact of Subconjuctivally Injected EGF and VEGF Inhibitors on Experimental Corneal Neovascularization in Rat Model

Current Eye Research ◽

10.3109/02713683.2011.601840 ◽

2011 ◽

Vol 36 (11) ◽

pp. 1005-1013 ◽

Cited By ~ 27

Author(s):

Ender Sener ◽

Nusen Yuksel ◽

Demir Kursat Yildiz ◽

Bulent Yilmaz ◽

Ozdemir Ozdemir ◽

...

Keyword(s):

Rat Model ◽

Corneal Neovascularization ◽

Vegf Inhibitors ◽

The Impact

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Initiating ECF bleaching sequences of eucalyptus kraft pulps with Z/D and Z/E stages

Holzforschung ◽

10.1515/hf.2010.008 ◽

2010 ◽

Vol 64 (1) ◽

Cited By ~ 6

Author(s):

Juan C. García ◽

Francisco López ◽

Antonio Pérez ◽

M. Angels Pèlach ◽

Pere Mutjé ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Chlorine Dioxide ◽

Ecological Impact ◽

Substantial Reduction ◽

Reference Sequence ◽

Kraft Pulps ◽

Eucalyptus Kraft Pulp ◽

The Impact ◽

Ecf Bleaching ◽

Ozone Bleaching

Abstract Ozone bleaching is a common practice in pulping, and also of eucalyptus, where it is usually applied in combination with bleaching sequences based on oxygen, hydrogen peroxide, or chlorine dioxide. Ozone has been proven to be a highly efficient and competitive bleaching chemical in terms of delignification efficiency, low costs, and reducing ecological impact. The objective of the present work was to evaluate technology with ozone/alkaline extraction (Z/E) and ozone/chlorine dioxide (Z/D) for bleaching of eucalyptus kraft pulp. Primarily, the impact of these bleaching steps on refinability and quality of pulp should be investigated. As reference, the sequence D*(EP)D (hot chlorine dioxide, extraction in presence of hydrogen peroxide, chlorine dioxide) was selected, which is considered as the state-of-the-art bleaching in elemental chlorine free (ECF) bleaching technology. Various bleaching sequences with ozone in their first step (Z/D(EP)DP, Z/D(EP)DD, Z/EDP, Z/EDD and A*Z/EDP) were found to provide kraft pulps of similar brightness and in similar yield as the reference sequence D*(EP)D. The kappa number, viscosity, and the contents of glucose and xylose, and hexenuronic acid of the pulps were also similar. In addition, the Z sequences resulted in a substantial reduction of the total chlorine dioxide consumption (more than 30.3% in all cases). The A*Z/EDP sequence, which proved to be the most efficient, yielded 87.5% ClO2 reduction. The studied bleaching sequences also resulted in substantially improved brightness reversal with regard to the reference sequence. The sequence A*Z/EDP was also the most efficient as regards the removal or organochlorines (OX) from the pulp and their reduction in the effluents (AOX). Ozone bleaching sequences improved paper strength, especially with the A*Z/EDP sequence.

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