A5016877888- Nitric Oxide and Endothelin Effects
- Redox biology and oxidative stress
- Trace Elements in Health
- Iron Metabolism and Disorders
- Sulfur Compounds in Biology
- Metal complexes synthesis and properties
- Hemoglobin structure and function
- Electrochemical Analysis and Applications
- Hemoglobinopathies and Related Disorders
- Eicosanoids and Hypertension Pharmacology
- Dental Erosion and Treatment
- Heme Oxygenase-1 and Carbon Monoxide
- Organometallic Complex Synthesis and Catalysis
- Insect and Pesticide Research
- Vitamin C and Antioxidants Research
- Blood Pressure and Hypertension Studies
- Neonatal Health and Biochemistry
- Electrochemical sensors and biosensors
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- Analytical Chemistry and Sensors
- Dental materials and restorations
- Cholinesterase and Neurodegenerative Diseases
- Renin-Angiotensin System Studies
- Microencapsulation and Drying Processes
- Pneumocystis jirovecii pneumonia detection and treatment
Universidade de São Paulo
2014-2024
Universidade de Ribeirão Preto
2012-2024
Universidade Federal do ABC
2009-2011
University of Alabama at Birmingham
2006-2008
Universidade Federal de São Carlos
2002-2003
A fundamental challenge to the study of oxidative stress responses Mycobacterium tuberculosis (Mtb) is understand how protective host molecules are sensed and relayed control bacilli gene expression. The genetic response Mtb hypoxia NO controlled by sensor kinases DosS DosT regulator DosR through activation dormancy/NO (Dos) regulon. However, regulatory ligands mechanism signal sensing were unknown. Here, we show that both bind heme as a prosthetic group rapidly autooxidized attain met...
Nitrosothiols (RSNO), formed from thiols and metabolites of nitric oxide (*NO), have been implicated in a diverse set physiological pathophysiological processes, although the exact mechanisms by which they are biologically unknown. Several candidate nitrosative pathways involve reaction *NO with O(2), reactive oxygen species (ROS), transition metals. We developed strategy using extracellular ferrocyanide to determine that under our conditions intracellular protein RSNO formation occurs...
One of the most important biological reactions nitric oxide (nitrogen monoxide, *NO) is its reaction with transition metals, which iron major target. This confirmed by ubiquitous formation EPR-detectable g=2.04 signals in cells, tissues, and animals upon exposure to both exogenous endogenous *NO. The source for these dinitrosyliron complexes (DNIC), relationship cellular homeostasis, not clear. Evidence has shown that chelatable pool (CIP) may be at least partially responsible this iron, but...
Proteins containing reactive cysteine residues (protein-Cys) are receiving increased attention as mediators of hydrogen peroxide signaling. These proteins mainly identified by mining the thiol proteomes oxidized protein-Cys in cells and tissues. However, it is difficult to determine if oxidation occurs through a direct reaction with or thiol–disulfide exchange reactions. Kinetic studies purified provide invaluable information about reactivity peroxide. Previously, we showed that...
Urate hydroperoxide is a product of the oxidation uric acid by inflammatory heme peroxidases. The formation urate might be key event in vascular inflammation, where there large amount and oxidizes glutathione sulfur-containing amino acids expected to react fast toward reactive thiols from peroxiredoxins (Prxs). kinetics for cytosolic 2-Cys Prx1 Prx2 revealed that these enzymes at rates comparable with hydrogen peroxide. second-order rate constants reactions were 4.9 × 105 2.3 106 m-1 s-1...
Abstract Typical 2-Cys Peroxiredoxins (2-Cys Prxs) reduce hydroperoxides with extraordinary rates due to an active site composed of a catalytic triad, containing peroxidatic cysteine (C P ), Arg, and Thr (or Ser). Prx are involved in processes such as cancer; neurodegeneration host-pathogen interactions. During catalysis, Prxs switch between decamers dimers. Analysis structures the fully folded (but not locally unfolded) form revealed highly conserved, non-conventional hydrogen bond (CH-π)...
Allosteric regulation of nitrite reduction by deoxyhemoglobin has been proposed to mediate nitric oxide (NO) formation during hypoxia. Nitrite is predominantly an anion at physiological pH, raising questions about the mechanism which it enters red blood cell (RBC) and whether this regulated coupled deoxyhemoglobin-mediated reduction. We tested hypothesis that transport RBCs fractional saturation. Using human RBCs, consumption was faster lower saturations, consistent with reactions deoxyheme....
Despite being one of the most important antioxidant defenses, Cu,Zn-superoxide dismutase (Sod1) has been frequently associated with harmful effects, including neurotoxicity. This toxicity attributed to immature forms Sod1 and extraneous catalytic activities. Among these, ability function as a peroxidase may be particularly relevant because it is increased in bicarbonate buffer produces reactive carbonate radical. many studies, how this radical remains unknown. To address question, we...
Nitrite reduces blood pressure (BP) in both clinical and experimental hypertension. This effect is attributable to the formation of nitric oxide (NO) other NO-related species, which may be improved by ascorbate or antioxidants. However, BP responses oral nitrite result, at least part, increased gastric S-nitrosothiol formation. study tested hypothesis that destroy S-nitrosothiols therefore not all doses enhance nitrite. We assessed sodim (0.2 mmol/kg) L-NAME hypertensive rats pretreated with...
While investigating peroxynitrite-dependent oxidation in murine RAW 264.7 macrophage cells, we observed that removal of the Labile Iron Pool (LIP) by chelation increases intracellular fluorescent indicator H2DCF, so concluded LIP reacts with peroxynitrite and decreases yield peroxynitrite-derived oxidants. This was a paradigm-shifting finding biochemistry raised many questions. In this follow-up study, address fundamental properties interaction between using same cellular model fluorescence...
In this study, we examined the mechanisms and kinetic profiles of intracellular nitrosative processes using diaminofluorescein (DAF-2) as a target in RAW 264.7 cells. The formation fluorescent, nitrosated product triazol (DAFT) from both endogenous exogenous nitric oxide (NO) was prevented by deoxygenation cell membrane-permeable superoxide (O2−) scavengers but not extracellular bovine Cu,Zn-SOD. addition, DAFT rate decreased presence Mn porphyrins that are known to scavenge peroxynitrite...
The complex trans-[Ru(NO)(NH3)4{P(OEt)3}](PF6)3 undergoes nucleophilic attack on the phosphorus ester ligand in solid state yielding trans-[Ru(NO)(NH3)4{P(OH)(OEt)2}](PF6)3. reaction was monitored and products analyzed using nuclear magnetic resonance spectroscopy (31P{¹H} CP-MAS NMR 31P{¹H} NMR), infrared (FTIR), electron paramagnetic (EPR), cyclic voltammetry (CV), electronic (UV-Vis) elemental analysis. According to experimental data quantum mechanical calculations (DFT), proceeds by...