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Reactive oxygen species attenuation in vitrified warmed bovine embryos.
Edição dos resumos da 37ª Annual Meeting of the Brazilian Embryo Technology Society
Aktivitas Reactive Oxygen Species Makrofag Akibat Stimulasi Gel Lidah Buaya Pada Infeksi Salmonella Typhimurium
Reactive Oxygen Species (ROS) merupakan salah satu lethal chemical yang dapatmembunuh dan mengeliminasi bakteri pada sel fagosit. Lidah Buaya (Aloevera) banyak dipakai sebagai pengobatan tradisional, tetapi belum ada buktiilmiah sampai tingkat seluler apalagi subseluler dalam hal efek imunostimulanpada penyakit infeksi. Tujuan penelitian ini adalah untuk mengetahui aktivitasimunostimulan dari gel lidah buaya yang ditunjukkan oleh aktivitas ROS makrofagsecara in vivo terhadap infeksi bakteri patogen Salmonella typhimurium. Sebanyak24 ekor mencit BABL/c betina umur 8-10 minggu berat 20-30 gram dikelompokkansecara acak menjadi empat kelompok, masing-masing kelompok enam ekor.Kelompok kontrol tidak diberi gel Aloe vera, sementara kelompok P1, P2, dan P3berturut-turut diberi gel Aloe vera 0,5 ml/ekor/hari; 1,0 ml/ekor/hari, dan 1,5ml/ekor/hari. Pemberian gel Aloe vera dilakukan selama sembilan hari. Pada harike-6, mencit diinfeksi bakteri patogen Salmonella typhimurium intraperitoneal105 CFU. Selanjutnya pada hari ke-10 mencit didislokasi dan dibedah, diambilmakrofag dari peritoneum untuk dianalisis produksi ROS-nya. Hasil penelitianmenunjukkan bahwa pemberian gel Aloe vera berpengaruh signi..ikan terhadappeningkatan produksi ROS makrofag mencit BALB/c yang diinfeksi Salmonellatyphimurium. Terdapat perbedaan secara signi..ikan antara kelompok kontroldengan kelompok P1, P2, dan P3, tetapi tidak terdapat perbedaan signi..ikan antarkelompok P1, P2, dan P3. Pemberian gel Aloe vera dosis 0,5 ml/ekor/hari sudahmampu meningkatkan produksi ROS makrofag. Reactive Oxygen Species (ROS) is one of lethal chemicals that can kill and eliminatebacteria in phagocytic cells. Aloe vera is widely used as traditional medicine, but thereis no scienti..ic evidence to prove the effect of immunostimulatory of the Aloe vera gel oninfectious disease in the cellular or subcellular level. This research aims to determinethe immunostimulatory activity of Aloe vera gel showed by ROS macrophage activityin vivo on the infection of bacterial pathogen Salmonella typhimurium. This researchused 24 female mice BABL/c age 8-10 weeks weight 20-30 Gram. They were groupedrandomly in four groups consisting of six mice each. The mice in the control groupwere not given the Aloe vera gel, while group P1 was given the gel of 0,5ml/mice/day,group P2 was 1,0ml/mice/day, and group P3 was 1,5ml/mice/day. The gel was givenin nine days, and in 6th day the mice were infected by bacterial pathogen Salmonellatyphimurium then in 10th day the mice were dissected to take their macrophage fromperitoneum for being analyzed its ROS production. The result showed that there wasa signi..icant difference between control group and P1, P2, and P3 group, but there isno signi..icant difference between P1, P2, and P3 group. In conclusion, the dose of 0,5ml/mice/day was able to increase ROS macrophage production
Reactive Oxygen Species
The term “reactive oxygen species” (ROS) refers to a group of reactive molecules and free radicals produced by molecular oxygen. In recent decades, there has been great interest in the role of ROS in various diseases. From basic science research to clinical trials, biomedical scientists have made rapid progress toward a better understanding of ROS-metabolizing systems and their role in health and diseases. This book includes sixteen chapters that address topics such as the history of ROS, its role in autoimmunity, neurodegeneration, and aging, and recent advances in various antioxidants and their therapeutic potential
Using exomarkers to assess mitochondrial reactive species in vivo
Background:
The ability to measure the concentrations of small damaging and signalling molecules such as reactive oxygen species (ROS) in vivo is essential to understanding their biological roles. While a range of methods can be applied to in vitro systems, measuring the levels and relative changes in reactive species in vivo is challenging.
Scope of review:
One approach towards achieving this goal is the use of exomarkers. In this, exogenous probe compounds are administered to the intact organism and are then transformed by the reactive molecules in vivo to produce a diagnostic exomarker. The exomarker and the precursor probe can be analysed ex vivo to infer the identity and amounts of the reactive species present in vivo. This is akin to the measurement of biomarkers produced by the interaction of reactive species with endogenous biomolecules.
Major conclusions and general significance:
Our laboratories have developed mitochondria-targeted probes that generate exomarkers that can be analysed ex vivo by mass spectrometry to assess levels of reactive species within mitochondria in vivo. We have used one of these compounds, MitoB, to infer the levels of mitochondrial hydrogen peroxide within flies and mice. Here we describe the development of MitoB and expand on this example to discuss how better probes and exomarkers can be developed. This article is part of a Special Issue entitled Current methods to study reactive oxygen species - pros and cons and biophysics of membrane proteins. Guest Editor: Christine Winterbourn.
Abbreviations:
EPR, electron paramagnetic resonance; GFP, green fluorescent protein; 4-HNE, 4-hydroxynonenal; MitoB, 3-(dihydroxyboronyl)benzyltriphenylphosphonium bromide; MitoP, (3-hydroxybenzyl)triphenylphosphonium bromide; ROS, reactive oxygen species; SOD, superoxide dismutase; TPMP, methyltriphenylphosphonium; TPP, triphenylphosphonium catio
Fluorescent Detection of Reactive Oxygen Species in Saccharomyces Cerevisiae Applied to Chronological Lifespan
During the course of normal aerobic metabolism, cells are exposed to a wide range of reactive oxygen species such as the superoxide anion, hydrogen peroxide, and the hydroxyl radical. These reactive oxygen species (ROS) are highly reactive metabolites of oxygen and can damage a wide range of macromolecules in the cell, including nucleic acids, proteins, and lipids, and can even, in some severe cases, lead to cell death. Normally, molecular oxygen is relatively unreactive and harmless in its ground state; however, it can undergo partial reduction via electrons that are leaked from the electron transport chain to form both the superoxide anion and hydrogen peroxide, both of which can react further to form the dangerously reactive hydroxyl radical. In order to combat the toxic and potentially deadly effects of ROS, cells are equipped with various antioxidant defense mechanisms, which include enzymes like superoxide dismutase 1 (Sod1p). Our objective is to observe these various reactive oxygen species using yeast (Saccharomyces cerevisiae) as a model organism and explore different biochemical staining assays such as Amplex Red (AR) and Dihydroethidium (DHE). These stains can both be used to track live cells and quantify ROS levels. This will allow us to study how ROS changes during chronological yeast lifespan. Although there are many types of reactive oxygen species that exist in various parts of the cell, our work thus far has aimed to track extracellular hydrogen peroxide via AR and superoxide generation in the mitochondria via DHE. Our initial results indicate that we are able to track superoxide production using DHE in wild type cell and sod1∆ yeast strains spectroscopically. Ultimately, we will use both fluorescence spectroscopy and live cell imaging via fluorescence microscopy to assess superoxide levels in multiple yeast strains. Our results will provide insight into the role of ROS in aging as we quantify levels during yeast lifespan
Fluorescent Detection of Reactive Oxygen Species in \u3cem\u3eSaccharomyces cerevisiae\u3c/em\u3e Applied to Chronological Lifespan
During the course of normal aerobic metabolism, cells are exposed to a wide range of reactive oxygen species such as the superoxide anion, hydrogen peroxide, and the hydroxyl radical. These reactive oxygen species (ROS) are highly reactive metabolites of oxygen and can damage a wide range of macromolecules in the cell, including nucleic acids, proteins, and lipids, and can even, in some severe cases, lead to cell death. Normally, molecular oxygen is relatively unreactive and harmless in its ground state; however, it can undergo partial reduction via electrons that are leaked from the electron transport chain to form both the superoxide anion and hydrogen peroxide, both of which can react further to form the dangerously reactive hydroxyl radical. In order to combat the toxic and potentially deadly effects of ROS, cells are equipped with various antioxidant defense mechanisms, which include enzymes like superoxide dismutase 1 (∆sod1). Our objective is to observe these various reactive oxygen species using yeast (Saccharomyces cerevisiae) as a model organism and explore different biochemical staining assays such as Amplex Red (AR) and Dihydroethidium (DHE). These stains can both be used to track live cells and quantify ROS levels. This will allow us to study how ROS changes during chronological yeast lifespan. Although there are many types of reactive oxygen species that exist in various parts of the cell, our work thus far has aimed to track extracellular hydrogen peroxide via AR and superoxide generation in the mitochondria via DHE. Our initial results indicate that we are able to track superoxide production using DHE in wild type cell and ∆sod1 yeast strains spectroscopically. Ultimately, we will use both fluorescence spectroscopy and live cell imaging via fluorescence microscopy to assess superoxide levels in multiple yeast strains. Our results will provide insight into the role of ROS in aging as we quantify levels during yeast lifespan
Biochemistry of Reactive Oxygen and Nitrogen Species
Reactive species or free radicals include reactive oxygen and nitrogen species that are called reactive oxygen nitrogen species. Reactive oxygen species are formed as a natural by-product of the normal metabolism of oxygen and have significant roles in cell signaling and homeostasis. The reactive oxygen species are generated as a by-product of biochemical reactions, in mitochondria, peroxisomes, cytochrome P450, and other cellular components. When oxygen homeostasis is not maintained, oxidative stress is increased in the cellular environment. Superoxide, hydrogen peroxide and hydroxyl radicals are normal metabolic by-products which are generated continuously by the mitochondria in growing cells. Microsomal cytochrome P450 enzymes, flavoprotein oxidases and peroxisomal enzymes are other significant intracellular sources of reactive oxygen species
Modulation of Mitochondrial Bioenergetics in the Isolated Guinea Pig Beating Heart by Potassium and Lidocaine Cardioplegia: Implications for Cardioprotection
Mitochondria are damaged by cardiac ischemia/reperfusion (I/R) injury but can contribute to cardioprotection. We tested if hyperkalemic cardioplegia (CP) and lidocaine (LID) differently modulate mitochondrial (m) bioenergetics and protect hearts against I/R injury. Guinea pig hearts (n = 71) were perfused with Krebs Ringer\u27s solution before perfusion for 1 minute just before ischemia with either CP (16 mM K+) or LID (1 mM) or Krebs Ringer\u27s (control, 4 mM K+). The 1-minute perfusion period assured treatment during ischemia but not on reperfusion. Cardiac function, NADH, FAD, m[Ca2+], and superoxide (reactive oxygen species) were assessed at baseline, during the 1-minute perfusion, and continuously during I/R. During the brief perfusion before ischemia, CP and LID decreased reactive oxygen species and increased NADH without changing m[Ca2+]. Additionally, CP decreased FAD. During ischemia, NADH was higher and reactive oxygen species was lower after CP and LID, whereas m[Ca2+] was lower only after LID. On reperfusion, NADH and FAD were more normalized, and m[Ca2+] and reactive oxygen species remained lower after CP and LID. Better functional recovery and smaller infarct size after CP and LID were accompanied by better mitochondrial function. These results suggest that mitochondria may be implicated, directly or indirectly, in protection by CP and LID against I/R injury
Impact of lipid content on oxygen reactive species and viability predictors in vitrified bovine embryos.
Given the significant variation in lipid levels among bovine embryos, our study was designed to associate lipid content to oxidative stress in individual embryos undergoing vitrification, and to assess how this and other morphological parameters impacts cryosurvival. Linear and logistic regression were performed to understand the influence of the variables in the cryosurvival. T-test or Kruskal Wallis were employed to compare means. Vitrified embryos revealed a positive correlation between lipid content and oxidative stress post-warming both 2 h (p = 0.025, n = 64) and 48 h (p < 0.001, n = 122) after warming. Lipid levels explained (p < 0.001) up to 51 % (multiple R-squared) of oxidative stress variability. Compared to fresh embryos, a negative influence (p = 0.01) of vitrification-warming procedures was detected in lipid levels. Vitrified embryos exhibited lower (p < 0.001, n = 90) mean lipid content compared to fresh counterparts 48 h post-warming, and similar (p = 0.24) oxidative stress levels. No impact of lipid content or oxidative stress levels was detected on hatchability or embryo quality 48 h post-warming (n = 99). Expansion just after (0 h) and 2 h after warming resulted in a higher chance of hatching (p = 0.015 and p = 0.008, OR 1.30 and 1.58), and a positive association was observed between expansion at 0 h (p = 0.002) and embryo area (p = 0.047) with cell number. In conclusion, a decrease in lipid levels was found following vitrification-warming procedure and an individual association between lipids and oxidative stress is present in vitrified embryos. Lipids or oxidative stress levels was not linked to survivability of vitrified embryos 48 h following warming. Expansion at 0 h indicates a better chance for hatching and higher cell numbers in vitrified embryos
Evidence for detrimental cross interactions between reactive oxygen and nitrogen species in Leber's hereditary optic neuropathy cells
Here we have collected evidence suggesting that chronic changes in the NO homeostasis and the rise of reactive oxygen species
bioavailability can contribute to cell dysfunction in Leber’s hereditary optic neuropathy (LHON) patients.We report that peripheral
blood mononuclear cells (PBMCs), derived froma female LHON patient with bilateral reduced vision and carrying the pathogenic
mutation 11778/ND4, display increased levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS), as revealed
by flow cytometry, fluorometric measurements of nitrite/nitrate, and 3-nitrotyrosine immunodetection. Moreover, viability assays
with the tetrazolium dye MTT showed that lymphoblasts from the same patient are more sensitive to prolonged NO exposure,
leading to cell death. Taken together these findings suggest that oxidative and nitrosative stress cooperatively play an important
role in driving LHON pathology when excess NO remains available over time in the cell environment
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