Chlorogenic acid prevents ovariectomized-induced bone loss by facilitating osteoblast functions and suppressing osteoclast formation.

Osteoporosis is a usual bone disease in aging populations, principally in postmenopausal women. Anti-resorptive and anabolic drugs have been applied to prevent and cure osteoporosis and are associated to a different of adverse effects. Du-Zhong is usually applied in Traditional Chinese Medicine to strengthen bone, regulate bone metabolism, and treat osteoporosis. Chlorogenic acid is a major polyphenol in Du-Zhong. In the current study, chlorogenic acid was found to enhance osteoblast proliferation and differentiation. Chlorogenic acid also inhibits the RANKL-induced osteoclastogenesis. Notably, ovariectomy significantly decreased bone volume and mechanical properties in the ovariectomized (OVX) rats. Administration of chlorogenic acid antagonized OVX-induced bone loss. Taken together, chlorogenic acid seems to be a hopeful molecule for the development of novel anti-osteoporosis treatment.

Anethole mitigates H2 O2 -induced inflammation in HIG-82 synoviocytes by suppressing the aquaporin 1 expression and activating the protein kinase A pathway.

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease affecting approximately 1% of the global population, with a higher prevalence in women than in men. Chronic inflammation and oxidative stress play pivotal roles in the pathogenesis of RA. Anethole, a prominent compound derived from fennel (Foeniculum vulgare), possesses a spectrum of therapeutic properties, including anti-arthritic, anti-inflammatory, antioxidant, and tumor-suppressive effects. However, its specific impact on RA remains underexplored. This study sought to uncover the potential therapeutic value of anethole in treating RA by employing an H2 O2 -induced inflammation model with HIG-82 synovial cells. Our results demonstrated that exposure to H2 O2 induced the inflammation and apoptosis in these cells. Remarkably, anethole treatment effectively countered these inflammatory and apoptotic processes triggered by H2 O2 . Moreover, we identified the aquaporin 1 (AQP1) and protein kinase A (PKA) pathway as critical regulators of inflammation and apoptosis. H2 O2 stimulation led to an increase in the AQP1 expression and a decrease in p-PKA-C, contributing to cartilage degradation. Conversely, anethole not only downregulated the AQP1 expression but also activated the PKA pathway, effectively suppressing cell inflammation and apoptosis. Furthermore, anethole also inhibited the enzymes responsible for cartilage degradation. In summary, our findings highlight the potential of anethole as a therapeutic agent for mitigating H2 O2 -induced inflammation and apoptosis in synovial cells, offering promising prospects for future RA treatments.

Let-7g Upregulation Attenuated the KRAS-PI3K-Rac1-Akt Axis-Mediated Bioenergetic Functions.

The aberrant activation of signaling pathways contributes to cancer cells with metabolic reprogramming. Thus, targeting signaling modulators is considered a potential therapeutic strategy for cancer. Subcellular fractionation, coimmunoprecipitation, biochemical analysis, and gene manipulation experiments revealed that decreasing the interaction of kirsten rat sarcoma viral oncogene homolog (KRAS) with p110α in lipid rafts with the use of naringenin (NGN), a citrus flavonoid, causes lipid raft-associated phosphatidylinositol 3-kinase (PI3K)-GTP-ras-related C3 botulinum toxin substrate 1 (Rac1)-protein kinase B (Akt)-regulated metabolic dysfunction of glycolysis and mitochondrial oxidative phosphorylation (OXPHOS), leading to apoptosis in human nasopharyngeal carcinoma (NPC) cells. The use of lethal-7g (let-7g) mimic and let-7g inhibitor confirmed that elevated let-7g resulted in a decrease in KRAS expression, which attenuated the PI3K-Rac1-Akt-BCL-2/BCL-xL-modulated mitochondrial energy metabolic functions. Increased let-7g depends on the suppression of the RNA-specificity of monocyte chemoattractant protein-induced protein-1 (MCPIP1) ribonuclease since NGN specifically blocks the degradation of pre-let-7g by NPC cell-derived immunoprecipitated MCPIP1. Converging lines of evidence indicate that the inhibition of MCPIP1 by NGN leads to let-7g upregulation, suppressing oncogenic KRAS-modulated PI3K-Rac1-Akt signaling and thereby impeding the metabolic activities of aerobic glycolysis and mitochondrial OXPHOS.

Folic Acid and Folinic Acid Protect Hearts of Aging Triple-transgenic Alzheimer's Disease mice via IGF1R/PI3K/AKT and SIRT1/AMPK Pathways.

Patients with Alzheimer's disease have increased risk of developing heart disease, which therefore highlights the need for strategies aiming at reducing Alzheimer's disease-related cardiovascular disease. Folic acid and folinic acid are beneficial to the heart. We aimed to investigate the benefits of folic acid and folinic acid in heart of patients with late-stage Alzheimer's disease. Twelve 16-month-old mice of triple-transgenic late-stage Alzheimer's disease were divided into three groups: Alzheimer's disease group, Alzheimer's disease + folic acid group, and Alzheimer's disease + folinic acid group. The mice were administered 12 mg/kg folic acid or folinic acid once daily via oral gavage for 3 months. In the folic acid and folinic acid treatment groups, the intercellular space was reduced, compared with the Alzheimer's disease group. TUNEL assay and western blot images showed that the number of apoptotic cells and the apoptosis-related protein expression were higher in the Alzheimer's disease group than in other two treated groups. Folic acid and folinic acid induced the IGF1R/PI3K/AKT and SIRT1/ AMPK pathways in the hearts of mice with Alzheimer's disease. Our results showed that folic acid and folinic acid treatment increased survival and SIRT1 expression to reduce apoptotic proteins in the heart. The aging mice treated with folinic acid had more IGF1R and SIRT1/AMPK axes to limit myocardial cell apoptosis. In conclusion, folic acid and folinic acid promote cardiac cell survival and prevent apoptosis to inhibit heart damage in aging mice with triple-transgenic late-stage Alzheimer's disease. In particular, folinic acid provides a better curative effect than folic acid.

Feasibility evaluation of N-Isopropyl Acrylamide 3D gel dosimeters for proton therapy.

This study aimed to investigate the feasibility of applying 3D gel dosimeters for proton therapy. Two different formulations (5-5-3-5, 5-3-3-10) for the N-Isopropyl Acrylamide (NIPAM) polymer gel were used to find the best composition for the application of NIPAM polymer gels for proton therapy. The reaction of the gel under different physical conditions, including dependence on energy and dependence on the dose rate of the NIPAM gel under proton irradiation, was also explored. A NIPAM gel dosimeter was used to record the 3D dose distribution, and a self-developed parallel beam optical computed tomography scanner was used to obtain non-irradiated and post-irradiated gel phantom images. The NIPAM gel was filled into a cylindrical acrylic phantom. The results showed that the optical density of the irradiated NIPAM dosimeter was linear in the dose range of 0 to 6 Gy, and the linearity of the two NIPAM gel formulations at the depth of the dose point (2 cm) was 0.98 to 0.89. The dose depth curves showed different patterns with different gel sensitivities. This study demonstrated that the NIPAM gel dosimeter with the 5-3-3-10 formulation is suitable for verifying the dosimetry dose of proton beams.

Ligustrazine improves the compensative effect of Akt survival signaling to protect liver Kupffer cells in trauma-hemorrhagic shock rats.

Trauma-hemorrhagic shock (THS) is a medical emergency that is encountered by physicians in the emergency department. Chuan Xiong is a traditional Chinese medicine and ligustrazine is a natural compound from it. Ligustrazine improves coronary blood flow and reduces cardiac ischemia in animals through Ca2+ and ATP-dependent vascular relaxation. It also decreases the platelets' bioactivity and reduces reactive oxygen species formation. We hypothesized that ligustrazine could protect liver by decreasing the inflammation response, protein production, and apoptosis in THS rats. Ligustrazine at doses of 100 and 1000 µg/mL was administrated in Kupffer cells isolated from THS rats. The protein expressions were detected via western blot. The THS showed increased inflammation response proteins, mitochondria-dependent apoptosis proteins, and had a compensation effect on the Akt pathway. After ligustrazine treatment, the hemorrhagic shock Kupffer cells decreased inflammatory response and mitochondria-dependent apoptosis and promoted a more compensative effect of the Akt pathway. It suggests ligustrazine reduces inflammation response and mitochondria-dependent apoptosis induced by THS in liver Kupffer cells and promotes more survival effects by elevating the Akt pathway. These findings demonstrate the beneficial effects of ligustrazine against THS-induced hepatic injury, and ligustrazine could be a potential medication to treat the liver injury caused by THS.

Ex Vivo Model to Evaluate the Antibacterial and Anti-Inflammatory Effects of Gelatin-Tricalcium Phosphate Composite Incorporated with Emodin and Lumbrokinase for Bone Regeneration.

Tricalcium phosphate (TCP) has gained attention due to its interconnected porous structures which promote fibrovascular invasion and bony replacement. Moreover, when gelatin is added and crosslinked with genipin (GGT), TCP exhibits robust biocompatibility and stability, making it an excellent bone substitute. In this study, we incorporated emodin and lumbrokinase (LK) into GGT to develop an antibacterial biomaterial. Emodin, derived from various plants, possesses antibacterial and anti-inflammatory properties. LK comprises proteolytic enzymes extracted from the earthworm Lumbricus rubellus and exhibits fibrinolytic activity, enabling it to dissolve biofilms. Additionally, LK stimulates osteoblast activity while inhibiting osteoclast differentiation. GGT was combined with emodin and lumbrokinase to produce the GGTELK composite. The biomedical effects of GGTELK were assessed through in vitro assays and an ex vivo bone defect model. The GGTELK composite demonstrated antibacterial properties, inhibiting the growth of S. aureus and reducing biofilm formation. Moreover, it exhibited anti-inflammatory effects by reducing the secretion of IL-6 in both in vivo cell experiments and the ex vivo model. Therefore, the GGTELK composite, with its stability, efficient degradation, biocompatibility, and anti-inflammatory function, is expected to serve as an ideal bone substitute.

Discovery of tetrasubstituted thiophenes as Cisd2 activators: A potential novel therapeutic option in nonalcoholic fatty liver disease.

Down-regulation of Cisd2 in the liver has been implicated in the development of nonalcoholic fatty liver disease (NAFLD) and increasing the level of Cisd2 is therefore a potential therapeutic approach to this group of diseases. Herein, we describe the design, synthesis, and biological evaluation of a series of Cisd2 activators, all thiophene analogs, based on a hit obtained using two-stage screening and prepared via either the Gewald reaction or by intramolecular aldol-type condensation of an N,S-acetal. Metabolic stability studies of the resulting potent Cisd2 activators suggest that thiophenes 4q and 6 are suitable for in vivo studies. The results from studies on 4q-treated and 6-treated Cisd2hKO-het mice, which carry a heterozygous hepatocyte-specific Cisd2 knockout, confirm that (1) there is a correlation between Cisd2 levels and NAFLD and (2) these compounds have the ability to prevent, without detectable toxicity, the development and progression of NAFLD.

Design, synthesis, and anticancer evaluation of 1-benzo[1,3]dioxol-5-yl-3-N-fused heteroaryl indoles.

A series of 1-benzo[1,3]dioxol-5-yl-indoles bearing 3-N-fused heteroaryl moieties have been designed based on literature reports of the activity of indoles against various cancer cell lines, synthesized via a Pd-catalyzed C-N cross-coupling, and evaluated for their anticancer activity against prostate (LNCaP), pancreatic (MIA PaCa-2), and acute lymphoblastic leukemia (CCRF-CEM) cancer cell lines. A detailed structure-activity relationship study culminated in the identification of 3-N-benzo[1,2,5]oxadiazole 17 and 3-N-2-methylquinoline 20, whose IC50 values ranged from 328 to 644 nM against CCRF-CEM and MIA PaCa-2. Further mechanistic studies revealed that 20 caused cell cycle arrest at the S phase and induced apoptosis in CCRF-CEM cancer cells. These 1-benzo[1,3]dioxol-5-yl-3-N-fused heteroaryl indoles may serve as a template for further optimization to afford more active analogs and develop a comprehensive understanding of the structure-activity relationships of indole anticancer molecules.

Neuroprotective Effects of Probiotic Lactobacillus reuteri GMNL-263 in the Hippocampus of Streptozotocin-Induced Diabetic Rats.

Diabetes-related brain complications have been reported in clinical patients and experimental models. The objective of the present study was to investigate the neuroprotective mechanisms of Lactobacillus reuteri GMNL-263 in streptozotocin (STZ)-induced diabetic rats. In this study, three different groups, namely control group, STZ-induced (55 mg/kg streptozotocin intraperitoneally) diabetic rats (DM), and DM rats treated with Lactobacillus reuteri GMNL-263 (1 × 109 CFU/rat/day), were utilized to study the protective effect of GMNL-263 in the hippocampus of STZ-induced diabetic rats. The results demonstrated that GMNL-263 attenuated diabetes-induced hippocampal damage by enhancing the cell survival pathways and repressing both inflammatory and apoptotic pathways. Histopathological analysis revealed that GMNL-263 prevented structural changes in the hippocampus in the DM group and decreased the level of inflammation and apoptosis in the hippocampus of DM rats. The IGF1R cell survival signaling pathway also improved after GMNL-263 treatment. These results indicate that probiotic GMNL-263 exerts beneficial effects in the brain of diabetic rats and has potential ability for clinical application.

Safety considerations for withdrawal of nucleos(t)ide analogues in patients with chronic hepatitis B: First, do no harm

Nucleos(t)ide analogues (NA) are widely used to treat hepatitis B virus (HBV) infection, but they cannot eradicate the virus and treatment duration can be lifelong if the endpoint is set at seroclearance of the hepatitis B surface antigen (HBsAg). As an alternative strategy, finite NA therapy without the prerequisite of HBsAg seroclearance has been proposed to allow treatment cessation in patients with sustained undetectable HBV viremia for two to three years. However, reactivation of viral replication almost always follows NA withdrawal. Whereas HBV reactivation might facilitate HBsAg seroclearance in some, it could lead to serious acute flare-ups in a certain proportion of patients. Occurrence and consequences of NA withdrawal flares are complicated with various factors involving the virus, host, and treatment. Accurate risk prediction for severe flares following NA cessation is essential to ensure patient safety. The risks of life-threatening flares in patients who discontinued NA according to the stopping rules of current guidelines or local reimbursement policies have recently been quantitatively estimated in large-scale studies, which also provided empirical evidence to help identify vulnerable patients at risk of devastating outcomes. Moreover, risk predictors were further explored and validated to hopefully aid in patient selection and management. In this narrative review with a focus on patient safety, we summarize and discuss current literature on the incidence of severe flares following NA cessation, risk stratification for candidate selection, rules of posttreatment monitoring, and indications for treatment resumption. We also share our thoughts on the limitations of existing knowledge and suggestions for future research.

Oxidation-mediated scaffold engineering of hyaluronic acid-based microcarriers enhances corneal stromal regeneration.

The functional design of scaffolding biomaterials with potent capabilities of promoting cell adhesion and proliferation is critically important for tissue repair and regeneration. Here, we exploit the effects of oxidation level of aldehyde hyaluronic acid (oHA) on gelatin microcarriers for repairing corneal injuries. Specifically, high oxidation levels can endow the microcarrier surface with large oHA grafting amount, smooth topography, and strong stiffness, consequently formulating biocompatible scaffolding materials with superior affinities for keratocyte attachment and growth. In a rabbit model of corneal alkali burn injury, single intracorneal injection of keratocytes/functionalized microcarriers with an appropriate oxidation level could effectively reduce corneal swelling (~62-fold improvement), recover ~94% collagen production and ~89% keratocan expression, and repair disordered collagenous stromal architecture after 4 weeks. These findings on the oxidation level effects of the aldehyde polysaccharide show a great potential use in the development of advanced scaffolds for efficient tissue engineering.

Remodeling Effects of the Combination of GGT Scaffolds, Percutaneous Electrical Stimulation, and Acupuncture on Large Bone Defects in Rats.

The regeneration defect of bone is a long-term physiological process after bone injuries. To accelerate the bone remodeling process, the combination of chemical and physical stimulations provides an efficient strategy to allow maturation and to functionalize osteoclasts and osteoblasts. This study aims to investigate the dual effects of a tricalcium phosphate (TCP)-based gelatin scaffold (GGT) in combination with electroacupuncture stimulation on the activation of osteoclasts and osteoblasts, as well as new bone regrowth in vitro and in vivo. We demonstrated that electrical stimulation changes the pH of a culture medium and activates osteoblasts and osteoclasts in an in vitro co-culture system. Furthermore, we showed that electroacupuncture stimulation can enhance osteogenesis and new bone regrowth in vivo and can upregulate the mechanism among parathyroid hormone intact (PTH-i), calcium, osteoclasts, and osteoblasts in the bone-defected rats. Those results showed the potential interest to combine the electroacupuncture technique with GGT scaffolds to improve bone remodeling after injury.

Snail Mucus Enhances Chemosensitivity of Triple-negative Breast Cancer Via Activation of the Fas Pathway.

BACKGROUND/AIM: The poor prognosis and chemoresistance of patients with triple-negative breast cancer (TNBC) urge the development of new therapeutic strategies. Snail mucus has shown its ability against inflammation, a process closely related to tumorigenesis, suggesting a potential anti-cancer activity. MATERIALS AND METHODS: The effect and mechanisms of snail mucus on cell viability were determined by IncuCyte Live-cell analysis and molecular biological methods. The anti-cancer fractions of snail mucus were isolated and identified by medium pressure liquid chromatography (MPLC) and nuclear magnetic resonance (NMR) spectrometry analysis. RESULTS: Snail mucus significantly decreased the viability of TNBC cells with relatively lower cytotoxicity to normal breast epithelial cells and enhanced their response to chemotherapy through activation of Fas signaling by suppressing nucleolin. Two peptide fractions have been identified as the anti-cancer ingredients of the snail mucus. CONCLUSION: Snail mucus can induce programmed cell death via the extrinsic apoptotic pathway and has therapeutic potential by achieving a chemo-sensitizing effect in TNBCs.

Arecoline induces cardiotoxicity by upregulating and activating cardiac hypertrophy-related pathways in Sprague-Dawley rats.

Habitual chewing of the areca nut increases the risk of mortality owing to cardiovascular disease, but few reports have revealed the cardiotoxicity mechanism of the areca nut. Arecoline has been reported to be the primary toxic constituent in the areca nut. In order to study the acute cardiotoxicity of the areca nut in the development of pathologic heart hypertrophy, we induced heart injury in rats using arecoline. Arecoline at a low dosage (5 mg/kg/day) or a high dosage (50 mg/kg/day) was intraperitoneally injected to Sprague-Dawley rats for 21 days. The change of heart function and biochemical pathways were investigated with echocardiography and Western blot. The results were presented that heart functions were weakened by arecoline stimulation, and western blotting analysis revealed an elevation in BNP levels in the heart after arecoline exposure. Arecoline induced IL-6-mediated activation of the MEK5/ERK5 and JAK2/STAT3 pathways, as well as mitogen-activated protein kinase signaling cascades. Further, arecoline increased the calcineurin and NFATc3 levels in the heart. In summary, our results suggest that arecoline causes significantly cardiotoxicity and heart damage by inducing several hypertrophy-related signaling pathways, including IL-6-induced MEK5/ERK5, JAK2/STAT3, mitogen-activated protein kinases, and calcineurin signaling pathways. The study elucidated, for the first time, the possible cardiac hypertrophy mechanisms underlying the cardiotoxicity of the areca nut.

Calycosin alleviates H2 O2 -induced astrocyte injury by restricting oxidative stress through the Akt/Nrf2/HO-1 signaling pathway.

Oxidative stress-induced brain cell damage is a crucial factor in the pathogenesis of reactive oxygen species (ROS)-associated neurological diseases. Further, studies show that astrocytes are an important immunocompetent cell in the brain and play a potentially significant role in various neurological diseases. Therefore, elimination of ROS overproduction might be a potential strategy for preventing and treating neurological diseases. Accumulating evidence indicates that calycosin, a main active ingredient in the Chinese herbal medicine Huangqi (Radix Astragali Mongolici), is a potential therapeutic candidate with anti-inflammation and/or anticancer effects. Here, we investigated the protective effect of calycosin in brain astrocytes by mimicking in vitro oxidative stress using H2 O2 . The results revealed that H2 O2 significantly induced ROS and inflammatory factor (tumor necrosis factor [TNF]-α and interleukin [IL]-1ß) production, whereas post-treatment with calycosin dramatically and concentration-dependently suppressed H2 O2 -induced damage by enhancing cell viability, repressing ROS and inflammatory factor production, and increasing superoxide dismutase (SOD) expression. Additionally, we found that calycosin facilitated nuclear factor erythroid 2-related factor 2 (Nrf2) expression and promoted its nuclear translocation, thereby inducing the expression of antioxidant molecules (heme oxygenase [HO]-1 and SOD) following H2 O2 treatment. Moreover, calycosin did not attenuated H2 O2 -induced astrocyte damage and ROS production in the presence of the ML385 (a Nrf2-specific inhibitor) and following Nrf2 silencing. Furthermore, calycosin failed to increase Akt phosphorylation and mitigate H2 O2 -induced astrocyte damage in the presence of the LY294002 (a selective phosphatidylinositol 3-kinase inhibitor), indicating that calycosin-mediated regulation of oxidative-stress homeostasis involved Akt/Nrf2/HO-1 signaling. These findings demonstrated that calycosin protects against oxidative injury in brain astrocytes by regulating oxidative stress through the AKT/Nrf2/HO-1 signaling pathway.

Fabrication of 3D Printed Poly(lactic acid)/Polycaprolactone Scaffolds Using TGF-ß1 for Promoting Bone Regeneration.

Our research was designed to evaluate the effect on bone regeneration with 3-dimensional (3D) printed polylactic acid (PLA) and 3D printed polycaprolactone (PCL) scaffolds, determine the more effective option for enhancing bone regeneration, and offer tentative evidence for further research and clinical application. Employing the 3D printing technique, the PLA and PCL scaffolds showed similar morphologies, as confirmed via scanning electron microscopy (SEM). Mechanical strength was significantly higher in the PLA group (63.4 MPa) than in the PCL group (29.1 MPa) (p < 0.01). Average porosity, swelling ratio, and degeneration rate in the PCL scaffold were higher than those in the PLA scaffold. SEM observation after cell coculture showed improved cell attachment and activity in the PCL scaffolds. A functional study revealed the best outcome in the 3D printed PCL-TGF-ß1 scaffold compared with the 3D printed PCL and the 3D printed PCL-Polydopamine (PDA) scaffold (p < 0.001). As confirmed via SEM, the 3D printed PCL- transforming growth factor beta 1 (TGF-ß1) scaffold also exhibited improved cell adhesion after 6 h of cell coculture. The 3D printed PCL scaffold showed better physical properties and biocompatibility than the 3D printed PLA scaffold. Based on the data of TGF-ß1, this study confirms that the 3D printed PCL scaffold may offer stronger osteogenesis.

Oral administration of green tea Epigallocatechin-3-gallate reduces oxidative stress and enhances restoration of cardiac function in diabetic rats receiving autologous transplantation of adipose-derived stem cells.

BACKGROUND: Cardio-dysfunction is one of the complications in patients with diabetes mellitus (DM). This paper aimed to investigate if oral administration of green tea Epigallocatechin-3-gallate (EGCG, E) and transplantation of adipose-derived stem cells (ADSC) show cross effects on the treatment of cardiomyopathy in rats with type 1 DM. MATERIALS AND METHODS: Wistar male rats were divided into four groups (each group contained 8 animals) including sham, DM (diabetic group), DM + ADSC (DM group with ADSC treatment) and DM + ADSC + E (DM + ADSC group with oral administration of EGCG). RESULTS: Pathological parameters including hypertrophy, inflammation, and fibrosis were activated in DM group. By contrast, all parameters were significantly improved in treatment group (DM + ADSC group). In addition, improvement of pathological parameters in DM + ADSC + E was significantly better than DM + ADSC. CONCLUSION: We found that EGCG can increase expression of survival marker in ADSC under high glucose environment and reduce serum oxidative stress in DM rats.

Doxorubicin-Gelatin/Fe3O4-Alginate Dual-Layer Magnetic Nanoparticles as Targeted Anticancer Drug Delivery Vehicles.

In this study, magnetic nanoparticles composed of a core (doxorubicin-gelatin) and a shell layer (Fe3O4-alginate) were developed to function as targeted anticancer drug delivery vehicles. The anticancer drug doxorubicin (DOX) was selected as a model drug and embedded in the inner gelatin core to obtain high encapsulation efficiency. The advantage of the outer magnetic layer is that it targets the drug to the tumor tissue and provides controlled drug release. The physicochemical properties of doxorubicin-gelatin/Fe3O4-alginate nanoparticles (DG/FA NPs) were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction. The mean diameter of DG/FA NPs, which was determined using a zeta potential analyzer, was 401.8 ± 3.6 nm. The encapsulation rate was 64.6 ± 11.8%. In vitro drug release and accumulation were also studied. It was found that the release of DOX accelerated in an acidic condition. With the manipulation of an external magnetic field, DG/FA NPs efficiently targeted Michigan Cancer Foundation-7 (MCF-7) breast cancer cells and showed in the nucleus after 6 h of incubation. After 12 h of incubation, the relative fluorescence intensity reached 98.4%, and the cell viability of MCF-7 cells decreased to 52.3 ± 4.64%. Dual-layer DG/FA NPs could efficiently encapsulate and deliver DOX into MCF-7 cells to cause the death of cancer cells. The results show that DG/FA NPs have the potential for use in targeted drug delivery and cancer therapy.

Bone Morphogenetic Protein-2-Activated 3D-Printed Polylactic Acid Scaffolds to Promote Bone Regrowth and Repair.

Uneven distribution of pores, lack of connection between holes, low reproducibility, insufficient mechanical strength, and incomplete volatility of organic solvents are some problems associated with traditional tissue engineering methods for bone defect repair. These characteristics reduce the quality and stability of products. This study uses 3D printing (3DP) to fabricate a biocompatible poly(lactic) acid-based scaffold for repairing bone tissue. Hence, three different types of scaffolds are assessed: a freeze-dried polylactic acid (PLA) scaffold constructed using the traditional freeze-extraction method; a 3D-PLA scaffold produced through the 3DP technique; and a 3D-PLA-bone morphogenetic protein-2 (BMP-2) scaffold that is prepared using 3DP technology, with the addition of BMP-2. To enhance biological activity, polydopamine (pDA) is used to graft BMP-2 on the surface of the 3D-PLA-BMP-2 scaffold. Then, the scaffolds are implanted into the bilateral femoral condyles of rabbits, and their ability to repair the bone tissue defects is tested. The results of the experiments reveal that the 3DP scaffolds are more biocompatible than the ones produced through the traditional manufacturing methods because they enhance cell adhesion and differentiation after pDA modification and BMP-2 fixation. In the future, the 3DP products may be applied for the repair of larger bone defects in the clinical setting.