Nanoparticulated Quercetin in Combating Age Related Cerebral Oxidative Injury

Abstract

Reactive oxygen species e.g. O(2)(*-), H(2)O(2) and *OH generated by the induction of oxidative stress exert a potential threat on the activity of endogenous antioxidant enzymes and substantially influence the aging process and age-dependant neuropathology. Chemical antioxidant is almost ineffective in protecting neuronal cells from oxidative damage as Blood Brain Barrier exists in between blood and brain interstitial fluid that restricts undegradable influx from the circulation into cerebral region. Quercetin (QC), a flavonoidal antioxidant is known as a potent antioxidant for its polyphenolic configuration. Formulation of QC in polylactide nanocapsule has been done and the efficacy of this vesicular flavonoid has been tested against cerebral ischemia induced oxidative damage in young and old rat brains. Antioxidant potential of QC loaded in nanocapsule (QC 7.2 mmol/kg b.wt., size 50 nm) was investigated by an in vivo model of cerebral ischemia and reperfusion on Sprague Dawley young (2 months, b.wt. 160-180 g) and aged (20 months, b.wt. 415-440 g) rats. Diene level, the index of lipid peroxidation and GSSG/GSH ratio were found to be higher in normal aged, compared to normal young rat brain. Endogenous antioxidants activities were lower in aged rat brain compared to young. Further reduction of these antioxidants were observed in aged rat brain by the induction of cerebral ischemia - reperfusion. Nanocapsule encapsulated QC treatment resulted a significant protection to endogenous antioxidant enzymes against ischemia induced oxidative damage in neuronal cells of young and old rats.

Nanoparticle transport across the blood brain barrier

“…Initially, Das and coworkers 29,97 proposed the use of LPs encapsulating quercetin, administered i.v. to rats (pre-treated with arsenic) as a good formulation to attenuate the oxidative damage induced by ischemia reperfusion injury in the rat brain.…”

Production of stabilized quercetin aqueous suspensions by supercritical fluid extraction of emulsions

“…It can scavenge reactive oxygen species, and down-regulate lipid peroxidation due to its ion chelating and iron stabilizing effect [1]. Furthermore it can promote the oxidation of Fe 2+ to Fe 3+ , which is less effective in generating free radicals.…”

Quercetin Protects Against Oxidative Stress Associated Damages in a Rat Model of Transient Focal Cerebral Ischemia and Reperfusion

“…Quercetin has been shown to have anti-inflammatory, anti-blood coagulation, anti-ischemic [9][10][11]. Neuroprotective effects have been demonstrated in a variety of brain injury models including ischemia/reperfusion showing improvement of morphological and functional outcomes [12][13][14][15]. Recently Lee et al [16] have investigated and reported the efficacy of Quercetin on cerebral ischemia/reperfusion injury.…”