Nitric Dioxide as Biologically Important Radical and its Role in Molecular Mechanism of Pancreatic Inflammation

Fluorescence quenching of 7-amino-4-methylcoumarin by different TEMPO derivatives

“…These protective effects are attributed mainly to the ability to catalyze the superoxide dismutation, as well as a detoxification of carbon-centered, alkoxy and peroxy radicals. A variety of TEMPO derivatives are additionally used as spin labels for supramolecular complexes reversible inhibitors for the nitroxide mediated polymerization, radical scavengers and anti-oxidant stabilizers for polymers [14][15][16][17]. Among the nitroxides studied the most interesting seems to be 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TEMPO-4-amino-4-carboxylic acid; TOAC), which is a member of the family of the conformational constrained C a -substituted a-amino acids and therefore can be used as a spin-label reporter of the orientation and dynamics of the peptide backbone [18].…”

Dihydroxycoumarins as highly selective fluorescent probes for the fast detection of 4-hydroxy-TEMPO in aqueous solution

“…It has been proven that 4-hydroxy-TEMPO interacts with nitrogen dioxide (one of the compounds responsible for nitrative stress) and decreases its concentration in cells up to 500-fold. 1,2 Pro-uorescent nitroxides have been previously reported as probes for the detection of free radicals, as well as the damage mediated by these species. [3][4][5] 4-Hydroxy-TEMPO, due to its low molecular weight, good superoxide dismutase mimic activity and low toxicity, has been selected as a good candidate for development as a preventive drug.…”

Cis-[Cr(C2O4)(pm)(OH2)2]+ Coordination Ion as a Specific Sensing Ion for H2O2 Detection in HT22 Cells

“…The increase in intracellular production of free radicals may lead to cellular damage, including alterations of lipids, proteins and DNA [4]. ROS [5,6], in particular superoxide anion (O 2 •− ), hydroxyl radical (OH • ) or hydrogen peroxide (H 2 O 2 ) and reactive nitrogen species [7,8,9,10], e.g., nitrogen dioxide, are highly cytotoxic. Superoxide anion is able to react with nitric oxide to form toxic peroxinitrite anions or dismutate into H 2 O 2 which in turn can be transformed into highly reactive and toxic hydroxyl radicals.…”