Oxidative damage of retinal pigment epithelium (RPE) cells plays an important role in the pathogenesis of blindness-related diseases, such as age-related macular degeneration (AMD). Quercetin, a bioactive flavonoid compound, has been shown to have a protective effect against oxidative stress-induced cell apoptosis and inflammation in RPE cells; however, the detailed mechanism underlying this protective effect is unclear. Therefore, the aim of this study was to investigate the regulatory mechanism of quercetin in a sodium iodate (NaIO3)-induced retinal damage. The clinical features of the mice, the production of oxidative stress, and the activity of autophagy and mitochondrial biogenesis were examined. In the mouse model, NaIO3 treatment caused changes in the retinal structure and reduced pupil constriction, and quercetin treatment reversed the oxidative stress-related pathology by decreasing the level of superoxide dismutase 2 (SOD2) while enhancing the serum levels of catalase and glutathione. The increased level of reactive oxygen species in the NaIO3-treated ARPE19 cells was improved by treatment with quercetin, accompanied by a reduction in autophagy and mitochondrial biogenesis. Our findings indicated that the effects of quercetin on regulating the generation of mtROS were dependent on increased levels of deacetyl-SOD2 through the Nrf2-PGC-1α-Sirt1 signaling pathway. These results demonstrated that quercetin may have potential therapeutic efficacy for the treatment of AMD through the regulation of mtROS homeostasis.

The group 2 allergen, Der p2, has been reported to activate innate toll-like receptors (TLRs) on respiratory epithelial cells and thus aggravate respiratory diseases. In this study, a highly sensitive nanostructured biosensor based on a 3D sensing element with uniformly deposited gold nanoparticles is proposed for the detection of the dust mite antigen Der p2. The barrier layer comprises an anodic aluminum oxide (AAO) film which is used as the template in this highly sensitive nanostructured biosensor. Simple electrochemical deposition without reducing agent and stabilizer was enough to uniformly synthesize gold nanoparticles on the surface of the barrier layer. The size and the distribution density of the nanoparticles can be well controlled by the applied potential during electrochemical deposition. Following this procedure, the dust mite monoclonal antibodies (IgG) were then immobilized through the 11-MUA (11-mercaptoundecanoic acid), (1-ethyl-3-(3-dimethyl-aminopropyl)-carbodiimide)/(N-hydroxysuccinimide) self-assembled monolayer approach for the dust mite antigen Der p2 detection. The detection limit of the proposed 3D gold nanoparticle-based nanostructured biosensor was examined using electrochemical impedance spectroscopy analysis and found to be 1 pg/mL. The dynamic range was found to be 5 mu g/mL. The proposed nanostructured biosensor would be useful for fast detection of rare molecules in a solution

Alzheimer's disease (AD) is characterized by accumulation of β-amyloid (Aβ) in senile plaques, contributing to oxidative stress, mitochondrial diseases, and synaptic atrophy, consequently leading to the deterioration of brain function. Adlay ( Coix lacryma-jobi L.) is an annual botanical. Here, a 95% ethanol extract of adlay hull (AHEE) was partitioned by ethyl acetate (AHEAE), n -butanol (AHBUE), and water (AHWE), and the effects of these extracts on lipopolysaccharide (LPS)-induced RAW264.7 cells and Aβ-induced PC12 cells, as experimental models of neurotoxicity, were evaluated. The expression of anti-inflammatory and antiapoptosis-related proteins was investigated and AHEE, AHEAE, and AHWE were found to exert anti-inflammatory effects. AHWE exhibited antiapoptotic effects and inhibited inducible nitric oxide synthase expression and nitric oxide production. We investigated the protective effects of AHWE against Aβ-induced neurotoxicity in dPC12 cells and explored the underlying mechanism. Pretreatment with AHWE significantly attenuated cell death and Aβ-mediated increase in B cell lymphoma (Bcl)-2/Bax ratio. AHWE significantly inhibited Aβ and enhanced protein kinase B (Akt) level in dPC12 cells, suggesting that its protective effect against Aβ-induced apoptosis in dPC12 cells was mediated through upregulation of the phosphoinositide 3-kinases (PI3K)/Akt signaling pathway. These extracts and its bioactive compound K36–21 may be potentially useful to treat neurodegenerative disorders.

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