A comparative study of resveratrol and resveratrol-functional selenium nanoparticles: Inhibiting amyloid β aggregation and reactive oxygen species formation properties : COMPARISON OF RESVERATROL AND RESVERATROL-FUNCTIONAL SELENIUM NANOPARTICLES

Aging is the major risk factor for neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. A large body of evidence indicates that oxidative stress is involved in the pathophysiology of these diseases. Oxidative stress can induce neuronal damages, modulate intracellular signaling, ultimately leading to neuronal death by apoptosis or necrosis. Thus antioxidants have been studied for their effectiveness in reducing these deleterious effects and neuronal death in many in vitro and in vivo studies. Increasing number of studies demonstrated the efficacy of polyphenolic antioxidants from fruits and vegetables to reduce or to block neuronal death occurring in the pathophysiology of these disorders. These studies revealed that other mechanisms than the antioxidant activities could be involved in the neuroprotective effect of these phenolic compounds. We will review some of these mechanisms and particular emphasis will be given to polyphenolic compounds from green tea, the Ginkgo biloba extract EGb 761, blueberries extracts, wine components and curcumin.

Oxidative stress is at the forefront of Alzheimer disease (AD) research. While its implications in the characteristic neurodegeneration of AD are vast, the most important aspect is that it seems increasingly apparent that oxidative stress is in fact a primary progenitor of the disease, and not merely an epiphenomenon. Moreover, evidence indicates that a long "dormant period" of gradual oxidative damage accumulation precedes and actually leads to the seemingly sudden appearance of clinical and pathological AD symptoms, including amyloid-beta deposition, neurofibrillary tangle formation, metabolic dysfunction, and cognitive decline. These findings provide important insights into the development of potential treatment regimens and even allude to the possibility of a preventative cure. In this review, we elaborate on the dynamic role of oxidative stress in AD and present corresponding treatment strategies that are currently under investigation. Copyright 2010 Elsevier Ltd. All rights reserved.

Selenium nanoparticles (SeNPs) have garnered a great deal of attention as potential cancer therapeutic payloads. However, the in vivo targeting drug delivery has been challenging. Herein, we describe the synthesis of tansferrin (Tf)-conjugated SeNPs and its use as a cancer-targeted drug delivery system to achieve enhanced cellular uptake and anticancer efficacy. Tf as targeting ligand significantly enhances the cellular uptake of doxorubicin (DOX)-loaded SeNPs through clathrin-mediated and caveolae/lipid raft-mediated endocytosis in cancer cells overexpressing transferrin receptor, and increases their selectivity between cancer and normal cells. DOX-loaded and Tf-conjugated SeNPs (Tf-SeNPs) exhibits unprecedented enhanced cytotoxicity toward cancer cells through induction of apoptosis with the involvement of intrinsic and extrinsic pathways. Internalized Tf-SeNPs triggers intracellular ROS overproduction, thus activates p53 and MAPKs pathways to promote cell apoptosis. In the nude mice xenograft experiment, Tf-SeNPs significantly inhibits the tumor growth via induction of p53-mediated apoptosis. This cancer-targeted design of SeNPs opens a new path for synergistic treating of cancer with higher efficacy and decreased side effects.