Quercetin binding accelerates prion fibrillation into proteinase sensitive and loosely structured amyloids.

Amyloidoses are caused by the deposition of amyloid fibrils ascribed to protein misfolding. In this study, we examined the antiamyloidogenic and antioxidative activities of quercetin, a plant flavonol from the flavonoid group of polyphenols, on mouse prion protein (moPrP) with biophysical approaches. As the results show, quercetin binds to the C-terminal region of moPrP, and quercetin binding does not affect the structure of moPrP.

The Effect of Octapeptide Repeats on Prion Folding and Misfolding.

Misfolding of prion protein (PrP) into amyloid aggregates is the central feature of prion diseases. PrP has an amyloidogenic C-terminal domain with three α-helices and a flexible tail in the N-terminal domain in which multiple octapeptide repeats are present in most mammals. The role of the octapeptides in prion diseases has previously been underestimated because the octapeptides are not located in the amyloidogenic domain.

Quercetin Disaggregates Prion Fibrils and Decreases Fibril-Induced Cytotoxicity and Oxidative Stress.

Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases caused by misfolding and aggregation of prion protein (PrP). Previous studies have demonstrated that quercetin can disaggregate some amyloid fibrils, such as amyloid β peptide (Aβ) and α-synuclein. However, the disaggregating ability is unclear in PrP fibrils.

Superelastic Multifunctional Aminosilane-Crosslinked Graphene Aerogels for High Thermal Insulation, Three-Component Separation, and Strain/Pressure-Sensing Arrays.

Aerogels have attracted great interest for their unique properties, but their mechanical brittleness and poor functionality highly limit their practical applications. Herein, we report unprecedented superelastic multifunctional aminosilane-crosslinked reduced graphene oxide (ACrGO) aerogels that are prepared via a facile and scalable strategy involving simultaneous crosslinking and reducing of graphene oxide nanosheets with different kinds of aminosilanes via C-N coupling and hydrolytic polycondensation reactions. It is found that 3-aminopropyl(diethoxy)methylsilane (APDEMS) is the better choice to enhance hydrophobicity, elasticity, and other properties of the resulting aerogels compared with (3-aminopropyl)triethoxysilane.

Sequential Photodynamic Therapy with Phthalocyanine Encapsulated Chitosan-Tripolyphosphate Nanoparticles and Flucytosine Treatment against .

Antibiotic resistance has become a crisis. () is one of the most highly virulent and drug-resistant pathogens. An alternative antimicrobial therapy to eradicate effectively, without the risk of developing drug-resistance, is needed.

EGFR-targeted photodynamic therapy by curcumin-encapsulated chitosan/TPP nanoparticles.

Background: Photodynamic therapy (PDT) is an effective therapy for cancers and is a minimally invasive therapy with low dark toxicity and limited side effects. PDT employs the combination of photosensitizers with a specific light source to produce reactive oxygen species (ROS) to damage tumor cells.

Methods: We fabricated nanoparticles encapsulating curcumin through crosslinking chitosan and tripolyphosphate (TPP).

Liberation of GPI-anchored prion from phospholipids accelerates amyloidogenic conversion.

Prion diseases or transmissible spongiform encephalopathies are a rare group of fatal neurodegenerative illnesses in humans and animals caused by misfolding of prion protein (PrP). Prion protein is a cell-surface glycosylphosphatidylinositol (GPI)-anchored glycoprotein expressed mostly in the central and peripheral nervous system, and this membrane-bound protein can be cleaved from the cell membranes by phosphoinositide phospholipase C. Numerous studies have investigated GPI-free recombinant PrP, but the role of GPI on misfolding of PrP is not well known.

Curcumin reduces amyloid fibrillation of prion protein and decreases reactive oxidative stress.

Misfolding and aggregation into amyloids of the prion protein (PrP) is responsible for the development of fatal transmissible neurodegenerative diseases. Various studies on curcumin demonstrate promise for the prevention of Alzheimer's disease and inhibition of PrPres accumulation. To evaluate the effect of curcumin on amyloid fibrillation of prion protein, we first investigated the effect of curcumin on mouse prion protein (mPrP) in a cell-free system.