A multifunctional biomimetic double-layer composite hydrogel with wet adhesion and antioxidant activity for dural repair.

Cerebrospinal fluid (CSF) leakage caused by accidents or diseases resulting from traumatic brain injury, inflammation, tumor erosion and surgery can lead to many complications. In this study, a multifunctional composite double-layer hydrogel was designed by simulating the structure of native dura mater, which was composed of polyacrylic acid (PAA), polyethyleneimine (PEI), sodium alginate (SA), β-cyclodextrin (β-CD) and edaravone (Ed). The PAA/PEI layer had strong wet adhesion characteristics, while the PEI/SA@β-CD/Ed layer exhibited significant antioxidant, drug release and biocompatibility properties.

Anti-Inflammatory Effect of Dimethyl Fumarate Associates with the Inhibition of Thioredoxin Reductase 1 in RAW 264.7 Cells.

Macrophages secrete a variety of pro-inflammatory cytokines in response to pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) but abnormal release of cytokines unfortunately promotes cytokine storms. Dimethyl fumarate (DMF), an FDA-approved drug for multiple sclerosis (MS) treatment, has been found as an effective therapeutic agent for resolution. In this study, the anti-inflammatory effect of DMF was found to correlate to selenoprotein thioredoxin reductase 1 (TXNRD1).

Carboxymethyl Chitosan and Gelatin Hydrogel Scaffolds Incorporated with Conductive PEDOT Nanoparticles for Improved Neural Stem Cell Proliferation and Neuronal Differentiation.

Tissue engineering scaffolds provide biological and physiochemical cures to guide tissue recovery, and electrical signals through the electroactive materials possess tremendous potential to modulate the cell fate. In this study, a novel electroactive hydrogel scaffold was fabricated by assembling poly(3,4-ethylenedioxythiophene) (PEDOT) nanoparticles on a carboxymethyl chitosan/gelatin (CMCS/Gel) composite hydrogel surface via in situ chemical polymerization. The chemical structure, morphology, conductivity, porosity, swelling rate, in vitro biodegradation, and mechanical properties of the prepared hydrogel samples were characterized.

Electrical stimulation enhances the neuronal differentiation of neural stem cells in three-dimensional conductive scaffolds through the voltage-gated calcium ion channel.

Electrical stimulation (ES) or electroconductive scaffold has been proved to have the positive effects on the behavior of neural stem cells (NSCs). We previously developed a novel three-dimensional conductive composite scaffold of poly (3, 4-ethylenedioxythiophen)/chitosan/gelatin (PEDOT/Cs/Gel) for neural tissue engineering. In the present study, we further studied the effect of three-dimensional conductive scaffolds combined with ES on the neuronal differentiation of NSCs.

Synthesis and characterization of protocatechuic acid grafted carboxymethyl chitosan with oxidized sodium alginate hydrogel through the Schiff's base reaction.

Excessive accumulation of free radicals is closely related to the occurrence and development of various neurodegenerative diseases. In this study, a novel protocatechuic acid grafted carboxymethyl chitosan with oxidized sodium alginate (PCA-g-CMCS/OSA) hydrogel was developed to maintain the oxidation-antioxidation balance activities. By optimizing the pH-soluble range (pH > 6.

C/N-Dependent Element Bioconversion Efficiency and Antimicrobial Protein Expression in Food Waste Treatment by Black Soldier Fly Larvae.

The black soldier fly (BSF), Hermetia illucens, has emerged as a promising species for waste bioconversion and source of antimicrobial proteins (AMPs). However, there is a scarcity of research on the element transformation efficiency and molecular characterization of AMPs derived from waste management. Here, food waste treatment was performed using BSF larvae (BSFL) in a C/N ratio of 21:1−10:1, with a focus on the C/N-dependent element bioconversion, AMP antimicrobial activity, and transcriptome profiling.

An Organic Solvent-Free Method for the Extraction of Ellagic Acid Compounds from Raspberry Wine Pomace with Assistance of Sodium Bicarbonate.

Industrial processing of raspberry juice and wine generates considerable byproducts of raspberry pomace. Ellagic acids/ellagitannins, being characterized by their antioxidant and antiproliferation properties, constitute the majority of polyphenolics in the pomace and are valuable for recovery. In the present study, we developed a novel procedure with sodium bicarbonate assisted extraction (SBAE) to recover ellagic acid from raspberry wine pomace.

Chlorophyllin Inhibits Mammalian Thioredoxin Reductase 1 and Triggers Cancer Cell Death.

Food colorants are widely used by humans in food production and preparation; however, their potential toxicity requires an in-depth analysis. In this study, five out of 15 commercial food colorants, namely, lutein, betanin, caramel, crocin and chlorophyll, significantly inhibited wild type selenoprotein thioredoxin reductase 1 (TrxR1, TXNRD1) in vitro. The hyperactive Sec residue of TrxR1 was targeted by those five colorants, which was confirmed by the site-directed mutagenesis of TrxR1.

Preparation, characterization and antioxidant activity of protocatechuic acid grafted carboxymethyl chitosan and its hydrogel.

In this study, protocatechuic acid (PCA) was grafted onto carboxymethyl chitosan (CMCS) via EDC/NHS to improve the antioxidant effect. The grafting ratio of PCA-g-CMCS conjugates could be controlled by adjusting the pH value and feed ratio of raw materials. The conjugates exhibited similar pH sensitivity to CMCS and showed dramatic enhancements of DPPH and ABTS radicals scavenging activities, total antioxidant capacity, reducing power, and Fe-chelating activity.

Mechanism Study of Bacteria Killed on Nanostructures.

It is important to study the bactericidal mechanism with nanostructures for the design and preparation of high-efficiency sterilization materials. In this paper, the interfacial energy gradient between cells and nanopillars is proposed to be the driving force to promote cells to migrate into nanostructures and get killed. The expressions of interfacial energy and its gradient were first established, then the deformation of cells pressured by nanostructures was calculated.

3D culture of neural stem cells within conductive PEDOT layer-assembled chitosan/gelatin scaffolds for neural tissue engineering.

Neural stem cells (NSCs), as a self-renewing and multipotent cell population, have been widely studied for never regeneration. Engineering scaffold is one of the important factors to regulate NSCs proliferation and differentiation towards the formation of the desired cells and tissues. Because neural cells are electro-active ones, a conductive scaffold is required to provide three-dimensional cell growth microenvironments and appropriate synergistic cell guidance cues.

Biodegradable and electroconductive poly(3,4-ethylenedioxythiophene)/carboxymethyl chitosan hydrogels for neural tissue engineering.

Electroconductive hydrogels with excellent electromechanical properties have become crucial for biomedical applications. In this study, we developed a conductive composite hydrogel via in-situ chemical polymerization based on carboxymethyl chitosan (CMCS), as a biodegradable base macromolecular network, and poly(3,4-ethylenedioxythiophene) (PEDOT), as a conductive polymer layer. The physicochemical and electrochemical properties of conductive hydrogels (PEDOT/CMCS) with different contents of PEDOT polymer were analyzed.

Synthesis of protocatechuic acid grafted chitosan copolymer: Structure characterization and in vitro neuroprotective potential.

Excessive free radicals can cause oxidative damage to human tissues, which results in a variety of diseases. Therefore, the development of antioxidant materials is one of the great projects in biomedical field. In this work, antioxidant protocatechuic acid (PCA) monomers were grafted onto chitosan (CS) backbones to develop a PCA grafted chitosan (PCA-g-CS) antioxidant copolymer via the method of free radical-induced grafting reaction.

Neural stem cell proliferation and differentiation in the conductive PEDOT-HA/Cs/Gel scaffold for neural tissue engineering.

Engineering scaffolds with excellent electro-activity is increasingly important in tissue engineering and regenerative medicine. Herein, conductive poly(3,4-ethylenedioxythiophene) doped with hyaluronic acid (PEDOT-HA) nanoparticles were firstly synthesized via chemical oxidant polymerization. A three-dimensional (3D) PEDOT-HA/Cs/Gel scaffold was then developed by introducing PEDOT-HA nanoparticles into a chitosan/gelatin (Cs/Gel) matrix.

Novel nanoparticles with Cr substituted ferrite for self-regulating temperature hyperthermia.

For hyperthermia to be used under clinical conditions for cancer therapeutics the temperature regulation needs to be precise and accurately controllable. In the case of the metal nanoparticles used for such activities, a high coercivity is a prerequisite in order to couple more energy in a single heating cycle for efficient and faster differential heating. The chemically stable Co-Zn ferrite nanoparticles have typically not been used in such self-regulating hyperthermia temperature applications to date due to their low Curie temperature usually accompanied by a poor coercivity.

Chitosan/gelatin porous scaffolds assembled with conductive poly(3,4-ethylenedioxythiophene) nanoparticles for neural tissue engineering.

Electroactive biomaterials are widely explored as scaffolds for nerve tissue regeneration. Poly(3,4-ethylenedioxythiophene) (PEDOT) is a conductive polymer that has been chosen to construct tissue engineered scaffolds because of its excellent conductivity and non-cytotoxicity. In the present study, an electrically conductive scaffold was prepared by assembling PEDOT on a chitosan/gelatin (Cs/Gel) porous scaffold surface via in situ interfacial polymerization.

Hyaluronic acid doped-poly(3,4-ethylenedioxythiophene)/chitosan/gelatin (PEDOT-HA/Cs/Gel) porous conductive scaffold for nerve regeneration.

Conducting polymer, as a "smart" biomaterial, has been increasingly used to construct tissue engineered scaffold for nerve tissue regeneration. In this study, a novel porous conductive scaffold was prepared by incorporating conductive hyaluronic acid (HA) doped-poly(3,4-ethylenedioxythiophene) (PEDOT-HA) nanoparticles into a chitosan/gelatin (Cs/Gel) matrix. The physicochemical characteristics of Cs/Gel scaffold with 0-10wt% PEDOT-HA were analyzed and the results indicated that the incorporation of PEDOT-HA into scaffold increased the electrical and mechanical properties while decreasing the porosity and water absorption.

Fabrication and characterization of conductive poly (3,4-ethylenedioxythiophene) doped with hyaluronic acid/poly (l-lactic acid) composite film for biomedical application.

Poly 3,4-ethylenedioxythiophene (PEDOT), a polythiophene derivative, has been proved to be modified by chemical process as biocompatible conductive polymer for biomedical applications. In this study, novel hyaluronic acid (HA)-doped PEDOT nanoparticles were synthesized by the method of chemical oxidative polymerization, then conductive PEDOT-HA/poly(l-lactic acid) (PLLA) composite films were prepared. The physicochemical characteristics and biocompatibility of films were further investigated.

Protective effects of protocatechuic acid on acute lung injury induced by lipopolysaccharide in mice via p38MAPK and NF-κB signal pathways.

The study aims to investigate the effects of protocatechuic acid (PCA) separated from Chinese herbs, on acute lung injury (ALI) induced by lipopolysaccharide (LPS) in mice. The mouse model was induced by intraperitoneal injection of LPS at the dose of 5mg/kg body weight. Three doses of PCA (30, 15, 5 mg/kg) were administered to mice with intraperitoneal injection one hour prior to LPS exposure.

Pyrroloquinoline quinone against glutamate-induced neurotoxicity in cultured neural stem and progenitor cells.

Pyrroloquinoline quinone (PQQ), as a well-known redox enzyme cofactor, has been proven to play important roles in the regulation of cellular growth and development in mammals. Numerous physiological and medicinal functions of PQQ have so far been reported although its effect on neural stem and progenitor cells (NS/PCs) and the potential mechanism were even rarely investigated. In this study, the neuroprotective effects of PQQ were observed by pretreatment of NS/PCs with PQQ before glutamate injury, and the possible mechanisms were examined.

Mass transfer analysis of growth and substance metabolism of NSCs cultured in collagen-based scaffold in vitro.

The aim of this study is to analyze the growth and substance metabolism of neural stem cells (NSCs) cultured in biological collagen-based scaffolds. Mass transfer and metabolism model of glucose, lactic acid, and dissolved oxygen (DO) were established and solved on MATLAB platform to obtain the concentration distributions of DO, glucose, and lactic acid in culture system, respectively. Calculation results showed that the DO influenced their normal growth and metabolism of NSCs mostly in the in vitro culture within collagen-based scaffolds.

[Stimulation of sphingosine-1-phosphate on cardiomyogenic differentiation of mesenchymal stem cells].

To study the effect of sphingosine-1-phosphate (S1P) on the cardiomyogenic differentiation of human umbilical cord mesenchymal stem cells (UC-MSCs) and human adipose-derived mesenchymal stem cells (AD-MSCs), we seeded the cells in the culture plates and used cardiomyocyte culture medium (CMCM) combining with different concentration of S1P to induce UC-MSCs and AD-MSCs in vitro for 7, 14 and 28 days. Cardiomyogenic differentiations were identified through immunofluorescence staining, and the results were observed with fluorescence microscopy and confocal microscopy. The effects of S1P and CMCM on cell activity were evaluated by the methyl thiazolyl tetrazolium assay.

Chitosan/gelatin porous scaffolds containing hyaluronic acid and heparan sulfate for neural tissue engineering.

The novel chitosan (Cs)/gelatin (Gel) porous scaffolds containing hyaluronic acid (HA) and heparan sulfate (HS) were fabricated via freeze-drying technique, and their physicochemical characteristics including pore size, porosity, water absorption, and in vitro degradation and biocompatibility were investigated. It was demonstrated that the Cs/Gel/HA/HS composite scaffolds had highly homogeneous and interconnected pores with porosity above 96% and average pore size ranging from 90 to 140 μm and a controllable degradation rate. The scanning electron microscopic images, cell viability assay, and fluorescence microscopy observation revealed that the presence of HA and HS in the scaffolds significantly promoted initial neural stem and progenitor cells (NS/PCs) adhesion and supported long-time growth in three-dimensional environment.

Catalpol improves cholinergic function and reduces inflammatory cytokines in the senescent mice induced by D-galactose.

The neuroprotective effects of catalpol, an iridoid glycoside isolated from the fresh rehmannia roots, on the cholinergic system and inflammatory cytokines in the senescent mice brain induced by D-galactose were assessed. The results showed that acetylcholinesterase (AChE) activity increased in senescent mice brain and choline acetyltransferase (ChAT) positive neurons, detected by immunohistochemical staining, decreased remarkably in the basal forebrain of senescent mice. Simultaneously, muscarinic acetylcholine receptor M1 (mAChR1) expression declined in senescent mice brain by western blotting method.