The synergistic effects of quercetin-containing 3D-printed mesoporous calcium silicate/calcium sulfate/poly-ε-caprolactone scaffolds for the promotion of osteogenesis in mesenchymal stem cells

Quercetin-based biomaterials for enhanced bone regeneration and tissue engineering

Quercetin, a natural flavonoid, has been extensively researched for its potential in promoting bone regeneration and tissue engineering. This review aimed to provide a comprehensive overview of the applications of quercetin-based biomaterials in bone regeneration and tissue engineering. The review discusses several studies that have integrated quercetin into biomaterials such as electrospun fibers, hydrogels, microspheres, and nanoparticles. These biomaterials are engineered to imitate the natural extracellular matrix of bone, creating an environment conducive to cell attachment, growth, and differentiation. The investigations presented emphasize the potential of quercetin-derived biomaterials in improving bone regeneration, decreasing oxidative stress and inflammation, and facilitating bone tissue restoration. These biomaterials have demonstrated the ability to facilitate cell encapsulation, maintain consistent quercetin release patterns, and have been applied in a range of uses such as bone grafts, implants, and tissue engineering scaffolds. Biomaterials derived from quercetin are utilized in the treatment of bone-related disorders, including osteoporosis and bone defects. These materials enhance bone regeneration by providing a scaffold for new bone growth, promoting the development of new bone tissue, and improving the mechanical properties of bone tissue.

The release behavior and in vitro osteogenesis of quercetin-loaded bioactive glass/hyaluronic acid/sodium alginate nanocomposite paste

Injectable pastes based on bioactive compounds and natural polymers are of interest in non-invasive bone surgeries. Several quantities of quercetin (100, 150, and 200 μM) were added to a sol-gel derived mesoporous bioactive glass. Injectable pastes based on quercetin-loaded bioactive glass, sodium alginate, and hyaluronic acid were prepared. Aggregated nanoparticles of bioactive glass and quercetin-loaded bioactive glass with mesoporous morphologies were confirmed by TEM and BET techniques. The quercetin release study was assessed in phosphate-buffered solution medium over 200 h and the obtained data were fitted by different eqs. A sustained release of quercetin was found, in which a better regression coefficient was achieved using Weibull equation. Human-derived mesenchymal stem cells were utilized to determine alkaline phosphatase activity and bone-related protein expression by western blotting and real-time PCR evaluations. Quercetin-loaded pastes increased the levels of alkaline phosphatase activity and the expression of Collagen-1, Osteopontin, Osteocalcin, and Runx2 proteins in a concentration-dependent manner. Due to the mesoporous architecture and high specific surface area of bioactive glass, the paste made of these particles and sodium alginate/hyaluronic acid macromolecules is appropriate matrix for quercetin release, resulting in promoted osteogenesis. The further in vivo studies can support the osteogenesis capacity of the quercetin-loaded paste.

Porous Silica Nanomaterials as Carriers of Biologically Active Natural Polyphenols: Effect of Structure and Surface Modification

For centuries, humans have relied on natural products to prevent and treat numerous health issues. However, biologically active compounds from natural sources, such as polyphenols, face considerable challenges, due to their low solubility, rapid metabolism, and instability, which hinder their effectiveness. Advances in the nanotechnologies have provided solutions to overcoming these problems through the use of porous silica materials as polyphenol carriers. These materials possess unique properties, such as a high specific surface area, adjustable particle and pore sizes, and a surface that can be easily and selectively modified, which favor their application in delivery systems of polyphenols. In this review, we summarize and discuss findings on how the pore and particle size, structure, and surface modification of silica materials influence the preparation of efficient delivery systems for biologically active polyphenols from natural origins. The available data demonstrate how parameters such as adsorption capacity, release and antioxidant properties, bioavailability, solubility, stability, etc., of the studied delivery systems could be affected by the structural and chemical characteristics of the porous silica carriers. Results in the literature confirm that by regulating the structure and selecting the appropriate surface modifications, the health benefits of the loaded bioactive molecules can be significantly improved.

CD62E- and ROS-Responsive ETS Improves Cartilage Repair by Inhibiting Endothelial Cell Activation through OPA1-Mediated Mitochondrial Homeostasis

Background: In the environment of cartilage injury, the activation of vascular endothelial cell (VEC), marked with excessive CD62E and reactive oxygen species (ROS), can affect the formation of hyaluronic cartilage. Therefore, we developed a CD62E- and ROS-responsive drug delivery system using E-selectin binding peptide, Thioketal, and silk fibroin (ETS) to achieve targeted delivery and controlled release of Clematis triterpenoid saponins (CS) against activated VEC, and thus promote cartilage regeneration. Methods: We prepared and characterized ETS/CS and verified their CD62E- and ROS-responsive properties in vitro. We investigated the effect and underlying mechanism of ETS/CS on inhibiting VEC activation and promoting chondrogenic differentiation of bone marrow stromal cells (BMSCs). We also analyzed the effect of ETS/CS on suppressing the activated VEC-macrophage inflammatory cascade in vitro. Additionally, we constructed a rat knee cartilage defect model and administered ETS/CS combined with BMSC-containing hydrogels. We detected the cartilage differentiation, the level of VEC activation and macrophage in the new tissue, and synovial tissue. Results: ETS/CS was able to interact with VEC and inhibit VEC activation through the carried CS. Coculture experiments verified ETS/CS promoted chondrogenic differentiation of BMSCs by inhibiting the activated VEC-induced inflammatory cascade of macrophages via OPA1-mediated mitochondrial homeostasis. In the rat knee cartilage defect model, ETS/CS reduced VEC activation, migration, angiogenesis in new tissues, inhibited macrophage infiltration and inflammation, promoted chondrogenic differentiation of BMSCs in the defective areas. Conclusions: CD62E- and ROS-responsive ETS/CS promoted cartilage repair by inhibiting VEC activation and macrophage inflammation and promoting BMSC chondrogenesis. Therefore, it is a promising therapeutic strategy to promote articular cartilage repair.

An in-vitro evaluation of antifungal, anti-lungcancer (A549), and anti-hyperglycemic activities potential of Andrographis paniculata (Burm. f.) flower extract

The medical plant research has received more attention among researchers especially after the Covid-19 pandemic. This research performed to evaluate the antifungal, anti-lung cancer (A549), and anti-hyperglycemic activities of aqueous extract of Andrographis paniculata flower. Interestingly, A. paniculata flower aqueous extract contains pharmaceutically valuable phytochemicals such as alkaloid, phenolics, terpenoids, tannins, flavonoids, and protein. It also showed fine antifungal activity against test fungal pathogens in the following order as: Aspergillus niger > Fusarium solani > Trichoderma harzianum > A. parasiticus > P. expansum > Penicillium janthinellum with lowest MIC values as ranged from 100 to 300 μg mL-1. Interestingly, this aqueous extract also showed considerable anti-lung cancer activity, evidenced by dose and time dependent lung cancer cell line (A549) growth/proliferation inhibition/cytotoxicity activity (65%) at 300 μg mL-1 concentration. This can be achieved by plant extract through inducing the secretion of apoptosis related proteins such as TNF α, IFN-γ, and ınterleukin 2 leads to apoptosis in A549 cells. It also showed fine anti-diabetic activity by inhibiting α -amylase (58.41%) than α-glucosidase (54.74%) at 200 μg mL-1 concentration. The UV as well as FTIR results demonstrated that the aqueous extract of A. paniculata flower contains pharmaceutically valuable bioactive compounds, which may be responsible for the wide range of biomedical applications.

Quercetin inhibits the metabolism of arachidonic acid by inhibiting the activity of CYP3A4, thereby inhibiting the progression of breast cancer

BACKGROUND

Recent years have witnessed impressive growth in applying natural medicine in tumor treatment. Saffron is reported to elicit an inhibitory property against BC. Herein, we sought to explore the specific components and mechanistic basis of saffron's anti-breast carcinoma (BC) function.

METHODS

Bioinformatics analysis was employed to analyze saffron components' anti-BC activity and screen the corresponding target genes involved in BC. Then, the roles of the main saffron ingredient quercetin in the activity of BC cells were examined using CCK-8, MTS, flow cytometry, colony formation, Transwell, and Gelatin zymogram assays. Additionally, the interactions among Quercetin, EET, and Stat3 were assessed by immunofluorescence and Western blot, and LC-MS/MS determined the levels of AA, EETs, and CYP3A. Finally, BC xenograft mouse models were established to verify the anti-BC function of Quercetin in vivo.

RESULTS

Quercetin, the main active component of saffron, inhibited BC progression. Quercetin suppressed BC cell growth, migration, and invasion and inhibited CYP3A4 expression and activity in BC. Mechanistically, Quercetin down-regulated CYP3A4 to block the nuclear translocation of Stat3 by decreasing the metabolization of AA to EETs, thereby alleviating BC. Moreover, exogenously added EETs counteracted the anti-tumor effect of Quercetin on BC. Quercetin also inhibited the tumor growth of tumor-bearing nude mice.

CONCLUSION

Quercetin could inhibit the activity of CYP3A to down-regulate AA metabolites EETs, consequently hampering p-Stat3 and nuclear translocation, thus impeding BC development.

Hydrogels-A Promising Materials for 3D Printing Technology

Hydrogels are a promising material for a variety of applications after appropriate functional and structural design, which alters the physicochemical properties and cell signaling pathways of the hydrogels. Over the past few decades, considerable scientific research has made breakthroughs in a variety of applications such as pharmaceuticals, biotechnology, agriculture, biosensors, bioseparation, defense, and cosmetics. In the present review, different classifications of hydrogels and their limitations have been discussed. In addition, techniques involved in improving the physical, mechanical, and biological properties of hydrogels by admixing various organic and inorganic materials are explored. Future 3D printing technology will substantially advance the ability to pattern molecules, cells, and organs. With significant potential for producing living tissue structures or organs, hydrogels can successfully print mammalian cells and retain their functionalities. Furthermore, recent advances in functional hydrogels such as photo- and pH-responsive hydrogels and drug-delivery hydrogels are discussed in detail for biomedical applications.

Preparation of 3D printed calcium sulfate filled PLA scaffolds with improved mechanical and degradation properties

Scaffold is one of the key components for tissue engineering application. Three-dimensional (3D) printing has given a new avenue to the scaffolds design to closely mimic the real tissue. However, material selection has always been a challenge in adopting 3D printing for scaffolds fabrication, especially for hard tissue. The fused filament fabrication technique is one of the economical 3D printing technology available today, which can efficiently fabricate scaffolds with its key features. In the present study, a hybrid polymer-ceramic scaffold has been prepared by combining the benefit of synthetic biodegradable poly (lactic acid) (PLA) and osteoconductive calcium sulphate (CaS), to harness the advantage of both materials. Composite PLA filament with maximum ceramic loading of 40 wt% was investigated for its printability and subsequently scaffolds were 3D printed. The composite filament was extruded at a temperature of 160 °C at a constant speed with an average diameter of 1.66 ± 0.34 mm. PLA-CaS scaffold with ceramic content of 10%, 20%, and 40% was 3D printed with square pore geometry. The developed scaffolds were characterized for their thermal stability, mechanical, morphological, and geometrical accuracy. The mechanical strength was improved by 29% at 20 wt% of CaS. The porosity was found to be 50-60% with an average pore size of 550 µm with well-interconnected pores. The effect of CaS particles on the degradation behaviour of scaffolds was also assessed over an incubation period of 28 days. The CaS particles acted as porogen and improved the surface chemistry for future cellular activity, while accelerating the degradation rate.

Promising bioactive properties of quercetin for potential food applications and health benefits: A review

Naturally occurring phytochemicals with promising biological properties are quercetin and its derivatives. Quercetin has been thoroughly studied for its antidiabetic, antibacterial, anti-inflammatory, anti-Alzheimer's, anti-arthritic, antioxidant, cardiovascular, and wound-healing properties. Anticancer activity of quercetin against cancer cell lines has also recently been revealed. The majority of the Western diet contains quercetin and its derivatives, therefore consuming them as part of a meal or as a food supplement may be sufficient for people to take advantage of their preventive effects. Bioavailability-based drug-delivery systems of quercetin have been heavily studied. Fruits, seeds, vegetables, bracken fern, coffee, tea, and other plants all contain quercetin, as do natural colors. One naturally occurring antioxidant is quercetin, whose anticancer effects have been discussed in detail. It has several properties that could make it an effective anti-cancer agent. Numerous researches have shown that quercetin plays a substantial part in the suppression of cancer cells in the breast, colon, prostate, ovary, endometrial, and lung tumors. The current study includes a concise explanation of quercetin's action mechanism and potential health applications.

3D printing hybrid materials using fused deposition modelling for solid oral dosage forms

3D printing in the pharmaceutical and healthcare settings is expanding rapidly, such as the rapid prototyping of orthotics, dental retainers, drug-loaded implants, and pharmaceutical solid oral dosage forms. Through 3D printing, we have the capability to precisely control dose, release kinetics, and several aesthetic features of dosage forms such as colour, shape, and texture. Additionally, polypills can be created with combinations of medications in one solid dosage form at completely customisable strengths that would be extremely difficult to obtain commercially. As the technology and formulations developed through 3D printing are expanding, the development of new hybrid materials to obtain superior formulations are also gaining momentum. In this review we collate data on the importance of developing hybrid formulations of polymers, drugs and excipients necessary to produce reliable and high-quality 3D printed dosage forms with a special emphasis on fused deposition modelling (FDM). FDM technology is one of the most widely used forms of 3D printing and has demonstrated compatibility with unique polymer-based hybrids to allow for enhanced drug delivery, protection of thermolabile drugs, modifiable release kinetics, and more. The data collated covers different categories of hybrids as well as the methods used to fabricate them, and their respective effects on the properties of 3D printed solid oral dosage forms. Therefore, this review will provide an overview of upcoming and emerging trends in pharmaceutical 3D printing formulation compositions.

Traditional Chinese medicine promotes bone regeneration in bone tissue engineering

Bone tissue engineering (BTE) is a promising method for the repair of difficult-to-heal bone tissue damage by providing three-dimensional structures for cell attachment, proliferation, and differentiation. Traditional Chinese medicine (TCM) has been introduced as an effective global medical program by the World Health Organization, comprising intricate components, and promoting bone regeneration by regulating multiple mechanisms and targets. This study outlines the potential therapeutic capabilities of TCM combined with BTE in bone regeneration. The effective active components promoting bone regeneration can be generally divided into flavonoids, alkaloids, glycosides, terpenoids, and polyphenols, among others. The chemical structures of the monomers, their sources, efficacy, and mechanisms are described. We summarize the use of compounds and medicinal parts of TCM to stimulate bone regeneration. Finally, the limitations and prospects of applying TCM in BTE are introduced, providing a direction for further development of novel and potential TCM.

Polyphenol-Enriched Composite Bone Regeneration Materials: A Systematic Review of In Vitro Studies

One of the possible alternatives for creating materials for the regeneration of bone tissue supporting comprehensive reconstruction is the incorporation of active substances whose controlled release will improve this process. This systematic review aimed to identify and synthesize in vitro studies that assess the suitability of polyphenolics as additives to polymer-ceramic composite bone regeneration materials. Data on experimental studies in terms of the difference in mechanical, wettability, cytocompatibility, antioxidant and anti-inflammatory properties of materials were synthesized. The obtained numerical data were compiled and analyzed in search of percentage changes of these parameters. The results of the systematic review were based on data from forty-six studies presented in nineteen articles. The addition of polyphenolic compounds to composite materials for bone regeneration improved the cytocompatibility and increased the activity of early markers of osteoblast differentiation, indicating a high osteoinductive potential of the materials. Polyphenolic compounds incorporated into the materials presumably give them high antioxidant properties and reduce the production of reactive oxygen species in macrophage cells, implying anti-inflammatory activity. The evidence was limited by the number of missing data and the heterogeneity of the data.

The Role of Flavonoids in the Osteogenic Differentiation of Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) play an important role in developing bone tissue engineered constructs due to their osteogenic and chondrogenic differentiation potential. MSC-based tissue engineered constructs are generally considered a safe procedure, however, the long-term results obtained up to now are far from satisfactory. The main causes of these therapeutic limitations are inefficient homing, engraftment, and directional differentiation. Flavonoids are a secondary metabolite, widely existed in nature and have many biological activities. For a long time, researchers have confirmed the anti-osteoporosis effect of flavonoids through in vitro cell experiments, animal studies. In recent years the regulatory effects of flavonoids on mesenchymal stem cells (MSCs) differentiation have been received increasingly attention. Recent studies revealed flavonoids possess the ability to modulate self-renewal and differentiation potential of MSCs. In order to facilitate further research on MSCs osteogenic differentiation of flavonoids, we surveyed the literature published on the use of flavonoids in osteogenic differentiation of MSCs, and summarized their pharmacological activities as well as the underlying mechanisms, aimed to explore their promising therapeutic application in bone disorders and bone tissue engineered constructs.

3D-Printed Hydrogels in Orthopedics: Developments, Limitations, and Perspectives

Three-dimensional (3D) printing has been used in medical research and practice for several years. Various aspects can affect the finished product of 3D printing, and it has been observed that the impact of the raw materials used for 3D printing is unique. Currently, hydrogels, including various natural and synthetic materials, are the most biologically and physically advantageous biological raw materials, and their use in orthopedics has increased considerably in recent years. 3D-printed hydrogels can be used in the construction of extracellular matrix during 3D printing processes. In addition to providing sufficient space structure for osteogenesis and chondrogenesis, hydrogels have shown positive effects on osteogenic and chondrogenic signaling pathways, promoting tissue repair in various dimensions. 3D-printed hydrogels are currently attracting extensive attention for the treatment of bone and joint injuries owing to the above-mentioned significant advantages. Furthermore, hydrogels have been recently used in infection prevention because of their antiseptic impact during the perioperative period. However, there are a few shortcomings associated with hydrogels including difficulty in getting rid of the constraints of the frame, poor mechanical strength, and burst release of loadings. These drawbacks could be overcome by combining 3D printing technology and novel hydrogel material through a multi-disciplinary approach. In this review, we provide a brief description and summary of the unique advantages of 3D printing technology in the field of orthopedics. In addition, some 3D printable hydrogels possessing prominent features, along with the key scope for their applications in bone joint repair, reconstruction, and antibacterial performance, are discussed to highlight the considerable prospects of hydrogels in the field of orthopedics.

Cartilage Repair Using Clematis Triterpenoid Saponin Delivery Microcarrier, Cultured in a Microgravity Bioreactor Prior to Application in Rabbit Model

Cartilage tissue engineering provides a promising method for the repair of articular cartilage defects, requiring appropriate biological scaffolds and necessary growth factors to enhance the efficiency of cartilage regeneration. Here, a silk fibroin (SF) microcarrier and a clematis triterpenoid saponin delivery SF (CTS-SF) microcarrier were prepared by the high-voltage electrostatic differentiation and lyophilization method, and chondrocytes were carried under the simulated microgravity condition by a rotating cell culture system. SF and CTS-SF microspheres were relatively uniform in size and had a porous structure with good swelling and cytocompatibility. Further, CTS-SF microcarriers could sustainably release CTSs in the monitored 10 days. Compared with the monolayer culture, chondrocytes under the microgravity condition maintained a better chondrogenic phenotype and showed better proliferation ability after culture on microcarriers. Moreover, the sustained release of CTS from CTS-SF microcarriers upregulated transforming growth factor-β, Smad2, and Smad3 signals, contributing to promote chondrogenesis. Hence, the biophysical effects of microgravity and bioactivities of CTS-ST were used for chondrocyte expansion and phenotype maintenance in vitro. With prolonged expansion, SF- and CTS-SF-based microcarrier-cell composites were directly implanted in vivo to repair rabbit articular defects. Gross evaluations, histopathological examinations, and biochemical analysis indicated that SF- and CTS-SF-based composites exhibited cartilage-like tissue repair compared with the nontreated group. Further, CTS-SF-based composites displayed superior hyaline cartilage-like repair that integrated with the surrounding cartilage better and higher cartilage extracellular matrix content. In conclusion, these results provide an alternative preparation method for drug-delivered SF microcarrier and a culture method for maintaining the chondrogenic phenotype of seed cells based on the microgravity environment. CTS showed its bioactive function, and the application of CTS-SF microcarriers can help repair and regenerate cartilage defects.

TP53-mediated miR-2861 promotes osteogenic differentiation of BMSCs by targeting Smad7

Bone defect seriously affects the quality of life. Meanwhile, osteogenic differentiation in BMSCs could regulate the progression of bone defect. Transcription factors are known to regulate the osteogenic differentiation in BMSCs. The study aimed to investigate the detailed mechanism by which TP53 regulates the osteogenic differentiation. To study bone defect in vitro, BMSCs were isolated from spinal cord injury rats. CCK-8 assay was applied to test the cell viability. The mineralized nodules in BMSCs was tested by alizarin red staining. Meanwhile, TUNEL staining and flow cytometry were performed to test the cell apoptosis. mRNA expression was tested by qRT-PCR. Starbase and dual-luciferase reporter assay were used to predict the downstream mRNA of miR-2861. Moreover, western blot was applied to detect the protein expressions (TP53 and Smad7). BMSCs were successfully isolated from rats. The expressions of miR-2861 were significantly upregulated in osteogenic medium, compared with growth medium. MiR-2861 inhibitor significantly decreased the levels of OCN, ALP, BSP, and Runx2 in BMSCs. In addition, miR-2861 inhibitor notably inhibited the mineralized nodules, viability, and induced the apoptosis of BMSCs. Smad7 was identified to be the downstream target of miR-2861, and knockdown of Smad7 notably reversed miR-2861 inhibitor-induced inhibition of osteogenic differentiation and promotion of apoptosis in BMSCs. Moreover, miR-2861 was transcriptionally regulated by TP53 in BMSCs. TP53-meidiated miR-2861 promotes osteogenic differentiation of BMSCs by targeting Smad7. Thereby, our research might provide new methods for bone defect treatment.

Mechanical assessment and odontogenic behavior of a 3D-printed mesoporous calcium silicate/calcium sulfate/poly-ε-caprolactone composite scaffold

BACKGROUND/PURPOSE

Tissue engineering in dentistry has fundamentally changed the way endodontists assess treatment options. Our previous study found that quercetin-contained mesoporous calcium silicate/calcium sulfate (MSCSQ) could induce hard tissue defect region regeneration. This study focused on whether the MSCSQ scaffold could also be effective in regulating odontogenesis and dentin regeneration.

METHODS

In this study, we fabricated MSCSQ composite scaffolds using the 3D printing technique. The characteristics of the MSCSQ scaffold were examined by scanning electron microscope (SEM), and mechanical properties were also assessed. In addition, we evaluated the cell viability, cell proliferation, odontogenic-related protein expression, and mineralization behavior of human dental pulp stem cells (hDPSCs) cultured on different scaffolds.

RESULTS

We found the precipitation of spherical-apatite on the scaffold surface rapidly in short periods. The in-vitro results for cell behavior revealed that hDPSCs with an MSCSQ scaffold were significantly higher in cell viability as followed time points. In addition, the specific makers of odontogenesis, such as DSPP and DMP-1 proteins, were induced obviously after culturing the hDPSCs on the MSCSQ scaffold.

CONCLUSION

Our results demonstrated that MSCSQ scaffolds could enhance physicochemical and biological behaviors compared to mesoporous calcium silicate/calcium sulfate (MSCS) scaffolds. In addition, MSCSQ scaffolds also enhanced odontogenic and immuno-suppressive properties compared to MSCS scaffolds. These results indicated that MSCSQ scaffolds could be considered a potential bioscaffold for clinical applications and dentin regeneration.