a11-positive-amyloid-oligomer-preparation-assessment-using-dot

A11-positive &#946;-amyloid Oligomer Preparation and Assessment Using Dot Blotting Analysis

&#946;-amyloid (A&#946;) is a hydrophobic peptide with an intrinsic tendency to self-assemble into aggregates. Among various aggregates, A&#946; oligomer ...

Ningbo University

A cubic Pd and reduced graphene oxide modified glassy carbon electrode (Pd/RGO/GCE) was fabricated to simultaneously detect dopamine (DA) and uric acid (UA) by cyclic voltammetry (CV) and different pulse voltammetry (DPV) methods. Compared with Pd/GCE and RGO/GCE, the Pd/RGO/GCE exhibited excellent electrochemical activity in electrocatalytic behaviors. Performing the Pd/RGO/GCE in CV measurement, the well-defined oxidation peak potentials separation between DA and UA reached to 145mV. By using the differential pulse voltammetry (DPV) technique, the calibration curves for DA and UA were found linear with the concentration range of 0.45-421μM and 6-469.5μM and the detection limit (S/N =3) were calculated to be 0.18μM and 1.6μM, respectively. Furthermore, the Pd/RGO/GCE displayed high selectivity when it was applied into the determination of DA and UA even though in presence of high concentration of interferents. Additionally, the prepared electrochemical sensor of Pd/RGO/GCE demonstrated a practical feasibility in rat urine and serum samples determination.

Dopamine and uric acid electrochemical sensor based on a glassy carbon electrode modified with cubic Pd and reduced graphene oxide nanocomposite.

Herein, a sensitive photo-electrochemical sensor based on CN and reduced graphene oxide nanosheets modified glassy carbon electrode (CN-RGO/GCE) has been fabricated for the detection of rutin under UV light illumination. In CN-RGO catalyst, RGO not only works as a template but also promotes electron transfer, meanwhile, CN acts as a photocatalyst. Benefiting from the superior electron transfer capacity and efficient UV light effect of the CN-RGO catalyst, we get a photo-electrochemical sensor for the rutin detecting with a low detection limit of 1.78×10molL and an excellent linear range of 5×10-1.4×10molL. Meanwhile, the achieved CN-RGO/GCE demonstrated nice selectivity, good reproducibility as well as reliable stability. Moreover, compared with the electrochemical determination, the CN-RGO electrode provides a new way for rutin detection by photo-electrochemical method with a promising UV light responsive result.

Enhanced photo-electrochemical response of reduced graphene oxide and CN nanosheets for rutin detection.

Alzheimer's disease (AD), the most common neurodegenerative disorder, is characterized by neurofibrillary tangles, synaptic impairments, and loss of neurons. Oligomers of β-amyloid (Aβ) are widely accepted as the main neurotoxins to induce oxidative stress and neuronal loss in AD. In this study, we discovered that fucoxanthin, a marine carotenoid with antioxidative stress properties, concentration dependently prevented Aβ oligomer-induced increase of neuronal apoptosis and intracellular reactive oxygen species in SH-SY5Y cells. Aβ oligomers inhibited the prosurvival phosphoinositide 3-kinase (PI3K)/Akt cascade and activated the proapoptotic extracellular signal-regulated kinase (ERK) pathway. Moreover, inhibitors of glycogen synthase kinase 3β (GSK3β) and mitogen-activated protein kinase (MEK) synergistically prevented Aβ oligomer-induced neuronal death, suggesting that the PI3K/Akt and ERK pathways might be involved in Aβ oligomer-induced neurotoxicity. Pretreatment with fucoxanthin significantly prevented Aβ oligomer-induced alteration of the PI3K/Akt and ERK pathways. Furthermore, LY294002 and wortmannin, two PI3K inhibitors, abolished the neuroprotective effects of fucoxanthin against Aβ oligomer-induced neurotoxicity. These results suggested that fucoxanthin might prevent Aβ oligomer-induced neuronal loss and oxidative stress via the activation of the PI3K/Akt cascade as well as inhibition of the ERK pathway, indicating that further studies of fucoxanthin and related compounds might lead to a useful treatment of AD.

Fucoxanthin, a Marine Carotenoid, Attenuates β-Amyloid Oligomer-Induced Neurotoxicity Possibly via Regulating the PI3K/Akt and the ERK Pathways in SH-SY5Y Cells.

Zhang Ke

Ningbo Key Laboratory of Behavioral Neuroscience,
Zhejiang Provincial Key Laboratory of Pathophysiology,
School of Medicine,
Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine

Ningbo University

A11-positive β-amyloid Oligomer Preparation and Assessment Using Dot Blotting Analysis