Laser-Assisted Structuring of Graphene Films with Biocompatible Liquid Crystal Polymer for Skin/Brain-Interfaced Electrodes.

The work presented here introduces a facile strategy for the development of flexible and stretchable electrodes that harness the robust characteristics of carbon nanomaterials through laser processing techniques on a liquid crystal polymer (LCP) film. By utilizing LCP film as a biocompatible electronic substrate, control is demonstrated over the laser irradiation parameters to achieve efficient pattern generation and transfer printing processes, thereby yielding highly conductive laser-induced graphene (LIG) bioelectrodes. To enhance the resolution of the patterned LIG film, shadow masks are employed during laser scanning on the LCP film surface. This approach is compatible with surface-mounted device integration, enabling the circuit writing of LIG/LCP materials in a flexible format. Moreover, kirigami-inspired on-skin bioelectrodes are introduced that exhibit reasonable stretchability, enabling independent connections to healthcare hardware platforms for electrocardiogram (ECG) and electromyography (EMG) measurements. Additionally, a brain-interfaced LIG microelectrode array is proposed that combines mechanically compliant architectures with LCP encapsulation for stimulation and recording purposes, leveraging their advantageous structural features and superior electrochemical properties. This developed approach offers a cost-effective and scalable route for producing patterned arrays of laser-converted graphene as bioelectrodes. These bioelectrodes serve as ideal circuit-enabled flexible substrates with long-term reliability in the ionic environment of the human body.

Surface-mediated high antioxidant and anti-inflammatory effects of astaxanthin-loaded ultrathin graphene oxide film that inhibits the overproduction of intracellular reactive oxygen species.

BACKGROUND: Astaxanthin (AST) is known as a powerful antioxidant that affects the removal of active oxygen and inhibits the production of lipid peroxide caused by ultraviolet light. However, it is easily decomposed by heat or light during production and storage because of the unsaturated compound nature with a structural double bond. The activity of AST can be reduced and lose its antioxidant capability. Graphene oxide (GO) is an ultrathin nanomaterial produced by oxidizing layered graphite. The chemical combination of AST with GO can improve the dispersion properties to maintain structural stability and antioxidant activity because of the tightly bonded functionalized GO surface. METHODS: Layered GO films were used as nanocarriers for the AST molecule, which was produced via flow-enabled self-assembly and subsequent controlled solution deposition of RGD peptide and AST molecules. Synthesis of the GO-AST complex was also carried out for the optimized concentration. The characterization of prepared materials was analyzed through transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FT-IR), atomic force microscope (AFM), and Raman spectroscopy. Antioxidant activity was tested by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2.2-diphenyl-1-picrylhydrazyl (DPPH) assays. The antibacterial effect and antioxidant effects were monitored for the ultrathin GO/RGD/AST Film. Further, reactive oxygen species (ROS) assay was used to evaluate the anti-inflammatory effects on L-929 fibroblasts. RESULTS: Cotreatment of GO-AST solution demonstrated a high antioxidant combined effect with a high ABTS and DPPH radicals scavenging activity. The GO/RGD/AST film was produced by the self-assembly process exhibited excellent antibacterial effects based on physicochemical damage against E. coli and S. aureus. In addition, the GO/RGD/AST film inhibited H2O2-induced intracellular ROS, suppressed the toxicity of lipopolysaccharide (LPS)-induced cells, and restored it, thereby exhibiting strong antioxidant and anti-inflammatory effects. CONCLUSION: As GO nanocarrier-assisted AST exerted promising antioxidant and antibacterial reactions, presented a new concept to expand basic research into the field of tissue engineering.

A Simple Route to the Complexation of Lutein with Reduced Graphene Oxide Nanocarriers and Antioxidant Protection Against Blue Light.

BACKGROUND: The excellent physicochemical properties of graphene-based materials, including graphene oxide (GO) and reduced GO (rGO), offer significant technological potential as multifunctional nanomaterials in biomedical fields. Lutein is a type of carotenoid that forms human macular pigments in the retina, where it inhibits harmful blue light and contributes to the strengthening of the antioxidant defense of retinal pigment epithelium cells. METHODS: Synthesis of the Lutein-rGO (Lu-rGO) complex was carried out for the optimized concentration. Then characterization of material was analyzed through ultraviolet-visible spectrophotometer (UV-Vis spectra), Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM). Antioxidant activity of Lu-rGO complex was measured by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2.2-diphenyl-1-picrylhydrazyl (DPPH), glutathione (GSH) oxidation assay. Then, oxidative stress induction by blue light and analyzed intracellular reactive oxygen species (ROS). RESULTS AND CONCLUSION: Based on the FT-IR measurement, the reduction efficiency defined by area was found to be 87.3%, the ID/IG ratio of 0.98 demonstrated by the Lu-rGO complex in the Raman spectrum was slightly higher than that of the original GO. The exhibited significant decrease in the peak intensities of the oxygen functional groups of the XPS spectra of the Lu-rGO complex was observed compared with the GO. In the TEM image for the Lu-rGO complex, folded and wrinkled nanostructures over the lutein-covered rGO surface were evidenced by tight molecular binding. The Lu-rGO complex provided superior DPPH and ABTS radical scavenging activity than GO and lutein alone, and the oxidation of GSH was suppressed. It was confirmed that the content of intracellular ROS and lysosomes, increased by blue light, was reduced after treatment with the Lu-rGO complex on ARPE-19 cells. In summary, graphene-based nanocarriers could function as preventative antioxidants during photochemical ROS generation based on the mechanism of antioxidant action.

Bioinspired RGD-Engineered Bacteriophage Nanofiber Cues against Oxidative Stress.

Instructive tissue engineering biomaterials provide a vascular niche and protect oxidative stress in injured tissue. In this study, we exploited bioinspired bacteriophage nanofibers, previously recognized by their biochemical and structural cues inducing angiogenesis, as an antioxidant tissue engineering material. We demonstrated that topological cues of Arg-Gly-Asp (RGD)-engineered bacteriophage nanofibers provide angiogenic niches and cytoprotective functions against cellular oxidative stress with increased expression of antioxidant enzymes heme oxygenase-1 (HO-1) and NAD(P)H-quinone oxidoreductase 1 (NQO1) via the extracellular-signal-regulated kinase (ERK)-nuclear factor erythroid 2-related factor2 (Nrf2)-mediated signaling pathway, where a high density of RGD cues on the phage body support efficient interaction of cells with phage cues. These bioinspired RGD-engineered bacteriophage nanofibers can serve as a novel therapeutic platform for curing ischemic diseases.

Lutein protects human retinal pigment epithelial cells from oxidative stress­induced cellular senescence.

Oxidative stress­induced cellular senescence is an important contributor to the pathogenesis of age­related macular degeneration (AMD). Characteristics of premature cellular senescence include a loss of proliferation, change in cell shape, irreversible cell cycle arrest, and elevated senescence­associated ß­galactosidase (SA­ß­gal) activity. It was hypothesized that lutein may have anti­senescence potential and may be useful as a treatment for AMD. In the present study, premature cellular senescence was induced in ARPE­19 cells via treatment with H2O2 and the effects of lutein application were confirmed by observing cell morphology, lysosome contents, reactive oxygen species (ROS) generation and SA­ß­gal activity, and cell cycle progression. The protein expression was also analyzed via western blotting in order to identify the affected signaling pathways. The results revealed that H2O2 treatment induced premature cellular senescence in ARPE­19 cells, as evidenced by an increased production of ROS and SA­ß­gal, altered lysosome contents, changed cellular morphology and arrested cell cycle progression. However, when treated with lutein, ARPE­19 cells were effectively protected from these H2O2­induced effects. Western blot analysis revealed that lutein induced the expression of heme oxygenase­1, NAD(P)H quinone dehydrogenase 1, sirtuin (SIRT)­1, and SIRT3. Together, the results indicated that lutein protects cells from cellular senescence induced by oxidative stress; therefore, it may be able to suppress the progression of AMD. In addition, our increased understanding of the pathways through which lutein acts is useful for the development of novel therapies for the treatment of oxidative stress­associated retinal disease.

Kalopanacis Cortex extract-capped gold nanoparticles activate NRF2 signaling and ameliorate damage in human neuronal SH-SY5Y cells exposed to oxygen-glucose deprivation and reoxygenation.

Recently, environment-friendly synthesis of gold nanoparticles (GNPs) has been extensively explored by biologists and chemists. However, significant research is still required to determine whether "eco-friendly" GNPs are beneficial to human health and to elucidate the molecular mechanisms of their effects on human cells. We used human neuronal SH-SY5Y cells to show that treatment with Kalopanacis Cortex extract-capped GNPs (KC-GNs), prepared via an eco-friendly, fast, one-pot synthetic route, protected neuronal cells against oxygen-glucose deprivation/reoxygenation (OGD/R)-induced damage. To prepare GNPs, Kalopanacis Cortex was used without any chemical reducing and stabilizing agents. Ultraviolet-visible spectroscopy showed maximum absorbance at 526 nm owing to KC-GN surface plasmon resonance. Hydrodynamic size (54.02±2.19 nm) and zeta potential (-20.3±0.04 mV) were determined by dynamic light scattering. The average diameter (41.07±3.05 nm) was determined by high-resolution transmission electron microscopy. Energy-dispersive X-ray diffraction spectroscopy and X-ray diffraction confirmed the presence of assembled GNPs. Fourier transform infrared analysis suggested that functional groups such as O-H, C-C, and C-N participated in KC-GN formation. Cell viability assays indicated that KC-GNs restored the viability of OGD/R-treated SH-SY5Y cells. Flow cytometry demonstrated that KC-GNs inhibited the OGD/R-induced reactive oxygen species production and mitochondrial membrane potential disruption. KC-GNs also inhibited the apoptosis of OGD/R-exposed cells. Western blot analysis indicated that the OGD/R-induced cellular apoptosis and simultaneous increases in the expression of cleaved caspase-3, p53, p21, and B-cell lymphoma 2-associated X protein were reversed by KC-GNs. The KC-GN-mediated protection against OGD/R-induced neurotoxicity was diminished by NRF2 and heme oxygenase-1 gene knockdowns. Collectively, these results suggested that KC-GNs exerted strong neuroprotective effects on human neuronal cells, which might be attributed to the attenuation of OGD/R-induced neuronal cell injury through the NRF2 signaling pathway.

Gardenia jasminoides extract-capped gold nanoparticles reverse hydrogen peroxide-induced premature senescence.

This study reports a green approach for synthesis of gold nanoparticles using Gardenia jasminoides extract, and specifically, can potentially enhance anti senescence activity. Biological synthesis of gold nanoparticles is ecofriendly and effective for the development of environmentally sustainable nanoparticles compared with existing methods. Here, we developed a simple, fast, efficient, and ecofriendly approach to the synthesis of gold nanoparticles by means of a Gardenia jasminoides extract. These G. jasminoides extract-capped gold nanoparticles (GJ-GNPs) were characterized by UV-vis, high resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and Furrier transform infrared spectroscopy (FT-IR). The synthesized GJ-GNPs turned red and showed maximal absorbance at 540nm. Thus, GJ-GNPs were synthesized successfully. We hypothesized that GJ-GNPs would protect ARPE19 cells from hydrogen peroxide-induced premature senescence. SA-ß-gal activity was elevated in hydrogen peroxide-treated cells, however, this effect was attenuated by GJ-GNP treatment. Moreover, compared with the normal control, hydrogen peroxide treatment significantly increased lysosome content of the cells and production of reactive oxygen species (ROS). GJ-GNPs effectively attenuated the increase in lysosome content and ROS production in these senescent cells. According to cell cycle analysis, G2/M arrest was promoted by hydrogen peroxide treatment in ARPE19 cells, however, this change was reversed by GJ-GNPs. Western blot analysis showed that treatment with GJ-GNPs increased the expression of p53, p21, SIRT3, HO-1, and NQO1 in senescent cells. Our findings should advance the understanding of premature senescence and may lead to therapeutic use of GJ-GNPs in retina-related regenerative medicine.

Novel compound from Polygonum multiflorum inhibits inflammatory response in LPS-stimulated microglia by upregulating AMPK/Nrf2 pathways.

Polygonum multiflorum extracts are known to improve memory and learning ability, and have neuroprotective and anti-aging activity. However, its function and the underlying mechanisms in neuroinflammation-mediated neurodegenerative disease remain poorly understood. In the present study, we investigated the anti-neuroinflammatory effects of several compounds from P. multiflorum, and found a novel compound, CRPE55IB. The CRPE55IB-induced suppression of NO and PGE2 production correlated with inhibition of iNOS and COX-2 protein expression and promoter activity in lipopolysaccharide (LPS)-stimulated microglia. CRPE55IB also reduced the production of pro-inflammatory cytokines (TNF-α and IL-6) induced by LPS. Furthermore, investigation of the molecular mechanism indicated that CRPE55IB inhibited LPS-induced NF-κB activation by inactivating phosphorylation of IKKα/ß, and phosphorylation and degradation of IκBα. We further found that CRPE55IB inhibited the phosphorylation of ERK and JNK at a lower concentration than that for p38 MAPK. Further experiments revealed that CRPE55IB treatment considerably increased the activation of Nrf2/ARE, and the expression of its target genes, including HO-1 and NQO1. Moreover, the Knockdown of Nrf2, HO-1, and NQO1 by siRNA abrogated the inhibitory effect of CRPE55IB on iNOS and COX-2 promoter activity. CRPE55IB also induced phosphorylation of AMPK/LKB/CaMKII in microglia. Analysis using a specific inhibitor of AMPK demonstrated that AMPK activation was involved in CRPE55IB-induced HO-1 and NQO1 expression. In addition, the CRPE55IB-induced anti-neuroinflammatory effect was abrogated by a specific inhibitor of AMPK, indicating the important role of AMPK in CRPE55IB-induced anti-neuroinflammation. Collectively, these results demonstrate that CRPE55IB exerts anti-neuroinflammatory effects against LPS via the Nrf2/AMPK signaling pathways.

Gold-conjugated resveratrol nanoparticles attenuate the invasion and MMP-9 and COX-2 expression in breast cancer cells.

Gold nanoparticles (AuNPs) with antitumorigenic effects obstruct the initiation, development and progression of tumors via the regulation of various processes, such as proliferation and apoptosis. However, the effects of AuNPs on breast cancer metastasis have not been well studied, and their response to 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulation remains unclear. Therefore, we synthesized resveratrol-capped gold nanoparticles (Rev-AuNPs) using green nanotechnology and investigated their potential anti-invasive properties in human breast cancer cells in response to TPA stimulation. The Rev-AuNPs formed spherical nanoparticles of 22.28±2.98 nm in diameter. Next, we found that non-cytotoxic concentrations of Rev-AuNPs significantly suppressed the TPA-induced migration and invasion abilities of breast cancer cells. Rev-AuNPs suppressed TPA-induced enzymatic activity and the expression of matrix metalloproteinase (MMP)-9 and cyclooxygenase-2 (COX-2). Furthermore, Rev-AuNP treatment remarkably downregulated TPA-induced nuclear translocation and transcriptional activation of nuclear transcription factor-κB (NF-κB) and activator protein-1 (AP-1). Rev-AuNPs reduced the phosphorylation of phosphoinositide 3-kinase/Akt (PI3K/Akt) and extracellular signal-regulated kinase (ERK)1/2 signaling, but did not affect the phosphorylation of Jun N-terminal kinase (JNK) or p38 MAPK in the TPA-stimulated breast cancer cells. Notably, Rev-AuNPs generally showed better anti-invasive activity than resveratrol without cytotoxicity. The inhibitory effect of Rev-AuNPs on MMP-9, COX-2, NF-κB, AP-1, PI3K/Akt and ERK activation was stronger than that of resveratrol for the same concentrations. We also demonstrated that Rev-AuNPs induced heme oxygenase-1 (HO-1) expression and that the inhibition of MMP-9 and COX-2 expression and MMP-9 enzymatic activity of Rev-AuNPs were abrogated by siRNA knockdown of HO-1 expression. Our findings revealed that the anti-invasive effects of Rev-AuNPs in response to TPA-stimulation were mediated by the suppression of MMP-9, COX-2, NF-κB, AP-1, PI3K/Akt and ERK and/or the activation of HO-1 signaling cascades. This novel finding emphasizes the pharmacological ability of Rev-AuNPs to treat breast cancer metastasis.

Development of a porcine renal extracellular matrix scaffold as a platform for kidney regeneration.

Acellular scaffolds, possessing an intact three-dimensional extracellular matrix (ECM) architecture and biochemical components, are promising for regeneration of complex organs, such as the kidney. We have successfully developed a porcine renal acellular scaffold and analyzed its physical/biochemical characteristics, biocompatibility, and kidney reconstructive potential. Segmented porcine kidney cortexes were treated with either 1% (v/v) Triton X-100 (Triton) or sodium dodecyl sulfate (SDS). Scanning electron microscopy showed both treatments preserved native tissue architecture, including porosity and composition. Swelling behavior was higher in the Triton-treated compared with the SDS-treated scaffold. Maximum compressive strength was lower in the Triton-treated compared with the SDS-treated scaffold. Attenuated total reflective-infrared spectroscopy showed the presence of amide II (-NH) in both scaffolds. Furthermore, richer ECM protein and growth factor contents were observed in the Triton-treated compared with SDS-treated scaffold. Primary human kidney cell adherence, viability, and proliferation were enhanced on the Triton-treated scaffold compared with SDS-treated scaffold. Following murine in vivo implantation, tumorigenecity was absent for both scaffolds after 8 weeks and in the Triton-treated scaffold only, glomeruli-like structure formation and neovascularity were observed. We identified 1% Triton X-100 as a more suitable decellularizing agent for porcine renal ECM scaffolds prior to kidney regeneration.

Combined injection of three different lineages of early-differentiating human amniotic fluid-derived cells restores urethral sphincter function in urinary incontinence.

OBJECTIVE: To investigate whether a triple combination of early-differentiated cells derived from human amniotic fluid stem cells (hAFSCs) would show synergistic effects in urethral sphincter regeneration. MATERIALS AND METHODS: We early-differentiated hAFSCs into muscle, neuron and endothelial progenitor cells and then injected them into the urethral sphincter region of pudendal neurectomized ICR mice, as single-cell, double-cell or triple-cell combinations. Urodynamic studies and histological, immunohistochemical and molecular analyses were performed. RESULTS: Urodynamic study showed significantly improved leak point pressure in the triple-cell-combination group compared with the single-cell- or double-cell-combination groups. These functional results were confirmed by histological and immunohistochemical analyses, as evidenced by the formation of new striated muscle fibres and neuromuscular junctions at the cell injection site. Molecular analysis showed higher target marker expression in the retrieved urethral tissue of the triple-cell-combination group. The injection of early-differentiated hAFSCs suppressed in vivo host CD8 lymphocyte aggregations and did not form teratoma. The nanoparticle-labelled early-differentiated hAFSCs could be tracked in vivo with optical imaging for up to 14 days after injection. CONCLUSION: Our novel concept of triple-combined early-differentiated cell therapy for the damaged sphincter may provide a viable option for incontinence treatment.

Human amniotic fluid stem cell-derived muscle progenitor cell therapy for stress urinary incontinence.

The most promising treatment for stress urinary incontinence can be a cell therapy. We suggest human amniotic fluid stem cells (hAFSCs) as an alternative cell source. We established the optimum in vitro protocol for the differentiation from hAFSCs into muscle progenitors. These progenitors were transplanted into the injured urethral sphincter and their therapeutic effect was analyzed. For the development of an efficient differentiation system in vitro, we examined a commercial medium, co-culture and conditioned medium (CM) systems. After being treated with CM, hAFSCs were effectively developed into a muscle lineage. The progenitors were integrated into the host urethral sphincter and the host cell differentiation was stimulated in vivo. Urodynamic analysis showed significant increase of leak point pressure and closing pressure. Immunohistochemistry revealed the regeneration of circular muscle mass with normal appearance. Molecular analysis observed the expression of a larger number of target markers. In the immunogenicity analysis, the progenitor group had a scant CD8 lymphocyte. In tumorigenicity, the progenitors showed no teratoma formation. These results suggest that hAFSCs can effectively be differentiated into muscle progenitors in CM and that the hAFSC-derived muscle progenitors are an accessible cell source for the regeneration of injured urethral sphincter.