Osmanthus-Loaded PVP/PVA Hydrogel Inhibits the Proliferation and Migration of Oral Squamous Cell Carcinoma Cells CAL-27

Recent Advances in Functional Hydrogels for Treating Dental Hard Tissue and Endodontic Diseases

Oral health is the basis of human health, and almost everyone has been affected by oral diseases. Among them, endodontic disease is one of the most common oral diseases. Limited by the characteristics of oral biomaterials, clinical methods for endodontic disease treatment still face large challenges in terms of reliability and stability. The hydrogel is a kind of good biomaterial with an adjustable 3D network structure, excellent mechanical properties, and biocompatibility and is widely used in the basic and clinical research of endodontic disease. This Review discusses the recent advances in functional hydrogels for dental hard tissue and endodontic disease treatment. The emphasis is on the working principles and therapeutic effects of treating different diseases with functional hydrogels. Finally, the challenges and opportunities of hydrogels in oral clinical applications are discussed and proposed. Some viewpoints about the possible development direction of functional hydrogels for oral health in the future are also put forward. Through systematic analysis and conclusion of the recent advances in functional hydrogels for dental hard tissue and endodontic disease treatment, this Review may provide significant guidance and inspiration for oral disease and health in the future.

Hydrogel Loaded with Components for Therapeutic Applications in Hypertrophic Scars and Keloids

Hypertrophic scars and keloids are common fibroproliferative diseases following injury. Patients with pathologic scars suffer from impaired quality of life and psychological health due to appearance disfiguration, itch, pain, and movement disorders. Recently, the advancement of hydrogels in biomedical fields has brought a variety of novel materials, methods and therapeutic targets for treating hypertrophic scars and keloids, which exhibit broad prospects. This review has summarized current research on hydrogels and loaded components used in preventing and treating hypertrophic scars and keloids. These hydrogels attenuate keloid and hypertrophic scar formation and progression by loading organic chemicals, drugs, or bioactive molecules (such as growth factors, genes, proteins/peptides, and stem cells/exosomes). Among them, smart hydrogels (a very promising method for loading many types of bioactive components) are currently favoured by researchers. In addition, combining hydrogels and current therapy (such as laser or radiation therapy, etc.) could improve the treatment of hypertrophic scars and keloids. Then, the difficulties and limitations of the current research and possible suggestions for improvement are listed. Moreover, we also propose novel strategies for facilitating the construction of target multifunctional hydrogels in the future.

Mesoporous Titanium Dioxide Nanoparticles-Poly(N-isopropylacrylamide) Hydrogel Prepared by Electron Beam Irradiation Inhibits the Proliferation and Migration of Oral Squamous Cell Carcinoma Cells

An urgently needed approach for the treatment of oral squamous cell carcinoma (OSCC) is the development of novel drug delivery systems that offer targeted specificity and minimal toxic side effects. In this study, we developed an injectable and temperature-sensitive composite hydrogel by combining mesoporous titanium dioxide nanoparticles (MTNs) with Poly(N-isopropylacrylamide) (PNIPAAM) hydrogel to serve as carriers for the model drug Astragalus polysaccharide (APS) using electron beam irradiation. The characteristics of MTNs, including specific surface area and pore size distribution, were analyzed, and the characteristics of MTNs-APS@Hyaluronic acid (HA), such as microscopic morphology, molecular structure, crystal structure, and loading efficiency, were examined. Additionally, the swelling ratio, gel fraction, and microscopic morphology of the composite hydrogel were observed. The in vitro cumulative release curve was plotted to investigate the sustained release of APS in the composite hydrogels. The effects on the proliferation, migration, and mitochondrial membrane potential of CAL-27 cells were evaluated using MTT assay, scratch test, and JC-1 staining. The results indicated successful preparation of MTNs with a specific surface area of 147.059 m2/g and an average pore diameter of 3.256 nm. The composite hydrogel displayed temperature-sensitive and porous characteristics, allowing for slow release of APS. Furthermore, it effectively suppressed CAL-27 cells proliferation, migration, and induced changes in mitochondrial membrane potential. The addition of autophagy inhibitors chloroquine (CQ) and 3-methyladenine (3-MA) attenuated the migration inhibition (p < 0.05).

Green Nanoformulations of Polyvinylpyrrolidone-Capped Metal Nanoparticles: A Study at the Hybrid Interface with Biomimetic Cell Membranes and In Vitro Cell Models

Noble metal nanoparticles (NP) with intrinsic antiangiogenic, antibacterial, and anti-inflammatory properties have great potential as potent chemotherapeutics, due to their unique features, including plasmonic properties for application in photothermal therapy, and their capability to slow down the migration/invasion speed of cancer cells and then suppress metastasis. In this work, gold (Au), silver (Ag), and palladium (Pd) NP were synthesized by a green redox chemistry method with the reduction of the metal salt precursor with glucose in the presence of polyvinylpyrrolidone (PVP) as stabilizing and capping agent. The physicochemical properties of the PVP-capped NP were investigated by UV-visible (UV-vis) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopies, dynamic light scattering (DLS), and atomic force microscopy (AFM), to scrutinize the optical features and the interface between the metal surface and the capping polymer, the hydrodynamic size, and the morphology, respectively. Biophysical studies with model cell membranes were carried out by using laser scanning confocal microscopy (LSM) with fluorescence recovery after photobleaching (FRAP) and fluorescence resonance energy transfer (FRET) techniques. To this purpose, artificial cell membranes of supported lipid bilayers (SLBs) made with 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphocholine (POPC) dye-labeled with 7-nitro-2-1,3-benzoxadiazol-4-yl (NBD, FRET donor) and/or lissamine rhodamine B sulfonyl (Rh, FRET acceptor) were prepared. Proof-of-work in vitro cellular experiments were carried out with prostate cancer cells (PC-3 line) in terms of cytotoxicity, cell migration (wound scratch assay), NP cellular uptake, and cytoskeleton actin perturbation.

Effect of Citric Acid on Swelling Resistance and Physicochemical Properties of Post-Crosslinked Electrospun Polyvinyl Alcohol Fibrous Membrane

A series of electrospun polyvinyl alcohol (PVA) fiber membranes were crosslinked with citric acid (CA) at concentrations of 10, 20, and 30 wt.% (designated as CA10, CA20, and CA30). The effects of CA on the chemical structure, mechanical strength, swelling resistance, and cytotoxicity of the crosslinked PVA fibrous membranes were investigated. Infrared spectroscopy indicated the enhanced esterification of carboxyl and hydroxyl groups between CA and PVA. The modulus and strength of the electrospun PVA membrane increased due to the crosslinking between CA and PVA. The crosslinking of the PVA fiber matrix with CA increased the PVA binding point, thereby increasing the swelling resistance and modulus; however, the concentration of CA used was limited. Results showed that the water absorption of the PVA membranes decreased from 6.58 ± 0.04 g/g for CA10 to 3.56 ± 3.33 g/g for CA20 and 2.85 ± 0.40 g/g for CA30 with increasing CA. The water absorption remained unchanged after the membrane was soaked for a period of time, so no significant difference was found in the water absorption capacity of the same group after immersion from 1 h to 3 d. The tensile strength increased from 20.52 MPa of CA10 to 22.09 MPa of CA20. With an increased amount of CA used for crosslinking, the tensile strength and modulus of CA30 decreased to 11.48 and 13.94 MPa, respectively. Our study also showed that CA was not toxic to L929 cell viability when used for fiber crosslinking at less than 20 wt.% PVA, meaning it may be a good candidate as a support layer for guided tissue engineering.