Description
TEMPOL is a piperidine nitroxide and spin label with superoxide dismutase (SOD) mimetic activity. It inhibits lipid peroxidation in rat liver microsomes with 50% inhibition of microsomal lipid peroxidation (IP
50) values of 117, 61, and 381 μM for peroxidation induced by iron plus NADPH, iron plus ascorbate, and
t-butylhydroperoxide, respectively. TEMPOL (1 mM) inhibits production of superoxide anions by 92%
via a xanthine-xanthine oxidase reaction
in vitro. It reduces mean arterial pressure and heart rate in spontaneously hypertensive rats (ED
50s = 70 and 63 μmol/kg, respectively) when administered intravenously. TEMPOL is a cell-permeable spin label that has been used to quantify intracellular oxygen in various cell types by electron spin resonance (ESR) spectroscopy.
Chemical Properties
solid
Uses
Tempol, a water-soluble piperidine nitroxide derivative having nonspecific radical-scavenging and superoxide dismutase (SOD) activity, protects cultured aerobic, but not hypoxic, cells against radiation-induced killing. Protection does not depend on intracellular thiols and does not involve O2-depletion. Tempol reacts with peroxyl radicals and can also oxidize DNA-bound metal ions, thereby interfering with OH? generation.
Uses
A free radical scavenger
Uses
Spin label for EPR studies; phase transfer dehydration catalyst; antioxidant; inhibitor of olefin free radical polymerization.
Application
In biochemical research, 4-hydroxy-TEMPO has been investigated as an agent for limiting reactive oxygen species. It catalyzes the disproportionation of superoxide, facilitates hydrogen peroxide metabolism, and inhibits Fenton chemistry.4-Hydroxy-TEMPO, along with related nitroxides, are being studied for their potential antioxidant properties.On an industrial-scale 4-hydroxy-TEMPO is often present as a structural element in hindered amine light stabilizers, which are commonly used stabilizers in plastics, it is also used as a polymerisation inhibitor, particularly during the purification of styrene.
General Description
4-Hydroxy-TEMPO is a 4-substituted 2,2,6,6-tetramethylpiperidyl-1-oxy (TEMPO) derivative. It is a low-molecular weight compound and has been proposed as superoxide dismutase mimic.
Flammability and Explosibility
Non flammable
Biological Activity
Superoxide scavenger that displays neuroprotective, anti-inflammatory and analgesic effects.
References
1) Lipman et al. (2006), Neuroprotective effects if the stable nitroxide compound Tempol in 1-methyl-4-phenylpyridinium ion-induced neurotoxicity in the Nerve Growth Factor-differentiated model of pheochromocytoma PC12? cells; Eur. J. Pharmacol., 549 50
2) Guron et al. (2006), Acute effects of the superoxide dismutase mimetic tempol on split kidney function in two-kidney one-clip hypertensive rats; J. Hypertens., 24 387
3) Samuni and Barenholz (1997), Gamma-irradiation damage to liposomes differing in composition and their protection by nitroxides; Free Radic. Biol. Med., 23 972
4) Bernardy et al. (2017), Tempol, a Superoxide Dismutase Mimetic Agent, Inhibits Superoxide Anion-Induced Inflammatory Pain in Mice; Biomed. Res. Int., 2017 9584819
5) De Blasio et al. (2017), The superoxide dismutase mimetic tempol blunts diabetes-induced upregulation of NADPH oxidase and endoplasmic reticulum stress in a rat model of diabetic nephropathy; Eur. J. Pharmacol., 807 12
