288,119 research outputs found
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
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
The H+-ATP synthase: A gate to ROS-mediated cell death or cell survival
This article is part of a Special Issue entitled: 18th European Bioenergetic ConferenceCellular oxidative stress results from the increased generation of reactive oxygen species and/or the dysfunction of the antioxidant systems. Most intracellular reactive oxygen species derive from superoxide radical although the majority of the biological effects of reactive oxygen species are mediated by hydrogen peroxide. In this contribution we overview the major cellular sites of reactive oxygen species production, with special emphasis in the mitochondrial pathways. Reactive oxygen species regulate signaling pathways involved in promoting survival and cell death, proliferation, metabolic regulation, the activation of the antioxidant response, the control of iron metabolism and Ca2 + signaling. The reversible oxidation of cysteines in transducers of reactive oxygen species is the primary mechanism of regulation of the activity of these proteins. Next, we present the mitochondrial H+-ATP synthase as a core hub in energy and cell death regulation, defining both the rate of energy metabolism and the reactive oxygen species-mediated cell death in response to chemotherapy. Two main mechanisms that affect the expression and activity of the H+-ATP synthase down-regulate oxidative phosphorylation in prevalent human carcinomas. In this context, we emphasize the prominent role played by the ATPase Inhibitory Factor 1 in human carcinogenesis as an inhibitor of the H+-ATP synthase activity and a mediator of cell survival. The ATPase Inhibitory Factor 1 promotes metabolic rewiring to an enhanced aerobic glycolysis and the subsequent production of mitochondrial reactive oxygen species. The generated reactive oxygen species are able to reprogram the nucleus to support tumor development by arresting cell death. Overall, we discuss the cross-talk between reactive oxygen species signaling and mitochondrial function that is crucial in determining the cellular fateWork in the authors’ laboratory was supported by grants from the Ministerio de Educación y Ciencia (BFU2010-18903), by the Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII and by Comunidad de Madrid (S/2011-BMD-2402), Spain. The CBMSO receives an institutional grant from Fundación Ramón Arece
Properties of Reactive Oxygen Species by Quantum Monte Carlo
The electronic properties of the oxygen molecule, in its singlet and triplet
states, and of many small oxygen-containing radicals and anions have important
roles in different fields of Chemistry, Biology and Atmospheric Science.
Nevertheless, the electronic structure of such species is a challenge for
ab-initio computational approaches because of the difficulties to correctly
describe the statical and dynamical correlation effects in presence of one or
more unpaired electrons. Only the highest-level quantum chemical approaches can
yield reliable characterizations of their molecular properties, such as binding
energies, equilibrium structures, molecular vibrations, charge distribution and
polarizabilities. In this work we use the variational Monte Carlo (VMC) and the
lattice regularized Monte Carlo (LRDMC) methods to investigate the equilibrium
geometries and molecular properties of oxygen and oxygen reactive species.
Quantum Monte Carlo methods are used in combination with the Jastrow
Antisymmetrized Geminal Power (JAGP) wave function ansatz, which has been
recently shown to effectively describe the statical and dynamical correlation
of different molecular systems. In particular we have studied the oxygen
molecule, the superoxide anion, the nitric oxide radical and anion, the
hydroxyl and hydroperoxyl radicals and their corresponding anions, and the
hydrotrioxyl radical. Overall, the methodology was able to correctly describe
the geometrical and electronic properties of these systems, through compact but
fully-optimised basis sets and with a computational cost which scales as
, where is the number of electrons. This work is therefore opening
the way to the accurate study of the energetics and of the reactivity of large
and complex oxygen species by first principles
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
Cigarette Smoke Initiates Oxidative Stress-Induced Cellular Phenotypic Modulation Leading to Cerebral Aneurysm Pathogenesis.
OBJECTIVE: Cigarette smoke exposure (CSE) is a risk factor for cerebral aneurysm (CA) formation, but the molecular mechanisms are unclear. Although CSE is known to contribute to excess reactive oxygen species generation, the role of oxidative stress on vascular smooth muscle cell (VSMC) phenotypic modulation and pathogenesis of CAs is unknown. The goal of this study was to investigate whether CSE activates a NOX (NADPH oxidase)-dependent pathway leading to VSMC phenotypic modulation and CA formation and rupture.
APPROACH AND RESULTS: In cultured cerebral VSMCs, CSE increased expression of NOX1 and reactive oxygen species which preceded upregulation of proinflammatory/matrix remodeling genes (MCP-1, MMPs [matrix metalloproteinase], TNF-α, IL-1β, NF-κB, KLF4 [Kruppel-like factor 4]) and downregulation of contractile genes (SM-α-actin [smooth muscle α actin], SM-22α [smooth muscle 22α], SM-MHC [smooth muscle myosin heavy chain]) and myocardin. Inhibition of reactive oxygen species production and knockdown of NOX1 with siRNA or antisense decreased CSE-induced upregulation of NOX1 and inflammatory genes and downregulation of VSMC contractile genes and myocardin. p47phox-/- NOX knockout mice, or pretreatment with the NOX inhibitor, apocynin, significantly decreased CA formation and rupture compared with controls. NOX1 protein and mRNA expression were similar in p47phox-/- mice and those pretreated with apocynin but were elevated in unruptured and ruptured CAs. CSE increased CA formation and rupture, which was diminished with apocynin pretreatment. Similarly, NOX1 protein and mRNA and reactive oxygen species were elevated by CSE, and in unruptured and ruptured CAs.
CONCLUSIONS: CSE initiates oxidative stress-induced phenotypic modulation of VSMCs and CA formation and rupture. These molecular changes implicate oxidative stress in the pathogenesis of CAs and may provide a potential target for future therapeutic strategies
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