Interleukin-4-Loaded Heparin Hydrogel Regulates Macrophage Polarization to Promote Osteogenic Differentiation.

In bone tissue engineering, biological scaffolds are designed with structural and functional properties that closely resemble the extracellular environment, aiming to establish a microenvironment conducive to osteogenesis. Macrophages hold significant potential for promoting osteogenesis and modulating the biological behavior of tumor cells. Multiple coculture experiments of macrophages and osteoblasts have demonstrated that macrophage polarization significantly impacts osteogenesis. Therefore, exploring bone biomaterials that can modulate macrophage polarization holds great clinical significance. In this study, heparin was modified with maleimide and was used as a raw material to form a hydrogel with 4-am-PEG-SH. The compound was used to polarize macrophages and promote osteogenesis after combining with interleukin 4 (IL-4) by taking advantage of the electronegativity of heparin. The results revealed overexpressed M2 macrophage-related phenotypic genes and cocultivation with MC3T3-E1 cells demonstrated the osteogenesis-promoting effect of the loaded IL-4 heparin hydrogel. Previous research reported that hydrogel loaded with IL-4 can be used as a biomaterial for osteogenesis promotion. Heparin materials used in this paper are derived from clinically anticoagulant drugs and feature a simple operation. The synthesized hydrogel effectively binds cytokines, regulates macrophages to induce osteogenesis and has many potential clinical applications.

Effect of Fas and Bcl-2 DNA Damages Response Expression in Stem Cells on Apoptosis of Nucleus Pulposus of Intervertebral Disc.

The nucleus pulposus is an elastic jelly composed of crisscross fibrous reticular structures, namely, chondrocytes and proteoglycan mucoid matrix. Embryo and adult SC can resist the accumulation of genetic damage and repair them through various DNA repair mechanisms, thus preventing them from spreading to daughter cells. Fresh medullary tissue was fixed with 10% formaldehyde solution, embedded in paraffin, and sectioned at 4 m. The nucleus pulposus was stained with HE, and its degeneration was observed under light microscope. The average apoptotic index (AI) of 20 denatured nuclei was 50.230, the percentage of Fas-positive cells was 74.255%, and the percentage of Bcl-2-positive cells was 55.370%. The average apoptotic index (AI) was 28.317. The percentage of Fas-positive cells, Fas protein-positive cells, and Bcl-2 protein-positive cells in six normal nuclei was 41.717%, 41.717%, and 27.167%, respectively. The average AI value, Fas protein expression, and Bcl-2 protein expression in the two groups were significantly different (P < 0.05).

Treatment of Traumatic Cartilage Defects of Rabbit Knee Joint by Adipose Derived Stem Cells Combined with Kartogenin Hydroxyapatite Nano-Microsphere Complex.

Kartogenin (KGN) can effectively promote the differentiation of adipose derived stem cells (ADSCs) into chondrocytes. With the help of three-dimensional slow-release technology, nano-microspheres are generated and used for cartilage repair. First, KGN solution was prepared, which was dissolved in distilled water, and NaOH solution, HEPES buffer, sodium chloride particles, and hydroxyapatite (HA) solution were added to prepare KGN-HA gel solution containing KGN. ADSCs were isolated from the posterior iliac of four-week-old New Zealand rabbits. After 0.5 mL of rabbit second-generation ADSCs suspension was taken, 2 mL KGN-HA gel solution was added, and they were mixed well to obtain ADSCs/KGN-HA gel. After drying treatment, ADSCs/KGN-HA nanospheres were precipitated. In the experiment, the minimum inhibitory concentration (MIC) of Staphylococcus aureus (MIC) > 2 µg/mL in each group of KGN-HA gel solution was reached within 30 days. Group K3 had the highest KGN encapsulation rate and the largest cumulative release. The biological activity of ADSCs was good in the ADSCs/KGN-HA nanoparticle solution. After two weeks of incubation, the nanospheres were positive for type II collagen staining/toluidine blue staining, that was, chondrocyte phenotype. The rabbit knee articular cartilage defect model was established. The defect part was filled with ADSCs/KGN-HA gel, which was similar in color to the surrounding tissues. The two sides of the tissue section and the surrounding cartilage tissue healed well, and no carrier material remained. Moreover, the cells were round, with cartilage lacuna formed around them, and after the simple periosteum was covered and repaired, the surface was sunken. The cell structure changed, and the healing with the surroundings was poor. In summary, under the slow release of KGN, ADSCs/KGN-HA nanospheres made ADSCs maintain a good biological form, which grew and proliferated normally. The ADSCs/KGN-HA nanoparticles cultured in vitro had a good repair effect on the animal model of articular cartilage defects.

Long Noncoding RNA GAS5 Inhibits Osteogenic Differentiation through MicroRNA 382-3p/TAF1 Signaling.

Long noncoding RNAs (lncRNAs) have been confirmed as important regulators during osteogenic differentiation. Previous research has disclosed that growth arrest-specific transcript 5 (GAS5) can promote osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs), but the underlying regulatory mechanism of GAS5 during the osteogenic differentiation of hBMSCs is unclear. Osteogenic differentiation was induced in hBMSCs by using osteogenic medium (OM). Gene expression was assessed by quantitative real-time PCR (RT-qPCR) or Western blot assays as needed. Alkaline phosphatase (ALP) activity, ALP staining, and alizarin red S (ARS) staining assays were performed to evaluate the impact of GAS5, microRNA 382-3p (miR-382-3p), and TATA box binding protein-associated factor 1 (TAF1) on osteogenic differentiation in vitro. The interaction among GAS5, miR-382-3p, and TAF1 was determined by RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP), and luciferase reporter assays. Expression of GAS5 (transcript variant 2) was downregulated during the osteogenic differentiation of hBMSCs, and its overexpression retarded the osteogenic differentiation of hBMSCs. GAS5 inhibited miR-382-3p by targeting RNA-directed microRNA degradation (TDMD). miR-382-3p downregulation partially offset the promoted osteogenic differentiation of hBMSCs upon GAS5 silencing. TAF1 negatively modulated osteogenic differentiation, and it activated GAS5 transcription so as to form a positive GAS5-miR-382-3p-TAF1 feedback loop in hBMSCs. This research was the first to reveal that the GAS5-miR-382-3p-TAF1 feedback loop inhibited the osteogenic differentiation of hBMSCs, which provided new clues for exploring the mechanism of osteogenic differentiation and disclosed the potential of GAS5 as a promising target during osteogenic differentiation.

Development of Personalized Signature Based on the Immune Landscape to Predict the Prognosis of Osteosarcoma and the Response to Immunotherapy and Targeted Therapy.

As a heterogeneous and aggressive disease, osteosarcoma (OS) faces great challenges to prognosis and individualized treatment. Hence, we explore the role of immune-related genes in predicting prognosis and responsiveness to immunotherapy and targeted therapies in patients with OS based on the immunological landscape of osteosarcoma. Based on the database of the Therapeutical Applicable Research to Generate Effective Treatments (TARGET), single-sample gene set enrichment analysis (ssGSEA) was used to obtain the enrichment scores of 29 immune characteristics. A series of bioinformatics methods were performed to construct the immune-related prognostic signature (IRPS). Gene set enrichment analysis and gene set variation analysis were used to explore the biological functions of IRPS. We also analyzed the relationship between IRPS and tumor microenvironment. Lastly, the reactivity of IRPS to immune checkpoint therapy and targeted drugs was explored. The ssGSEA algorithm was used to define two immune subtypes, namely Immunity_High and Immunity_Low. Immunity_High was associated with a good prognosis and was an independent prognostic factor of OS. The IRPS containing 7 genes was constructed by the least absolute shrinkage and selection operator Cox regression. The IRPS can divide patients into low- and high-risk patients. Compared with high-risk patients, low-risk patients had a better prognosis and were positively correlated with immune cell infiltration and immune function. Low-risk patients benefited more from immunotherapy, and the sensitivity of targeted drugs in high- and low-risk groups was determined. IRPS can be used to predict the prognosis of OS patients, and provide therapeutic responsiveness to immunotherapy and targeted therapy.

Fabrication of silver nanoparticles/gelatin hydrogel system for bone regeneration and fracture treatment.

The present work aims to examine the effect of gelatin on the stabilization of silver nanoparticles (AgNPs) and their use in healing the bone fracture. AgNPs-loaded Gel hydrogels (AgNPs/Gel) were fabricated under sunlight using gelatin (Gel) as stabilizing agent. The characterization of the synthesized hydrogels was performed with the help of techniques such as UV-visible spectroscopy (UV-Vis) and high-resolution transmission electron microscopy (HR-TEM). Furthermore, the results of cell cytotoxicity confirmed that the AgNPs/Gel hydrogels are nonhazardous to osteoblasts. The outcome of cell fixation with AgNPs/Gel hydrogels after an incubation period of five days exposed the improved survival and spreading of osteoblasts cells on the prepared AgNPs/Gel hydrogels. Moreover, the AgNPs/Gel hydrogel nanostructures displayed their ability in modulating bone fracture healing, which suggests their potential use in nursing care.

Balloon pulmonary angioplasty vs riociguat in patients with inoperable chronic thromboembolic pulmonary hypertension: A systematic review and meta-analysis.

BACKGROUNDS: No previous meta-analyses have compared the efficacy and safety of BPA with riociguat therapy in inoperable CTEPH patients. METHODS: Relevant published studies were searched in the PubMed, Embase and ClinicalTrial.gov databases. RESULTS: Twenty-three clinical trials including 1454 patients (631 underwent BPA; 823 underwent riociguat therapy) were analyzed. BPA was associated with a greater improvement in RAP (mean difference (MD) = -3.53 mmHg, 95% CI: [-4.85, -2.21] vs MD = -1.05 mmHg, 95% CI: [-1.82, -0.29]); mPAP (MD = -15.02 mmHg, 95% CI: [-17.32, -12.71] vs MD = -4.19 mmHg, 95% CI: [-5.58, -2.80]); PVR (standard MD = -1.32 woods, 95% CI: [-1.57, -1.08] vs standard MD = -0.65 woods, 95% CI: [-0.79, -0.50]); NYHA functional class (RR = 6.78, 95% CI: [3.14, 14.64] vs RR = 1.49, 95% CI: [1.07, 2.07]); and 6MWD (MD = 71.66 m, 95% CI: [58.34, 84.99] vs MD = 45.25 m, 95% CI: [36.51, 53.99]) than riociguat treatment. However, the increase in CO was greater with riociguat (MD = 0.78 L/min, 95% CI: [0.61, 0.96]) than with BPA (MD = 0.33 L/min, 95% CI: [0.06, 0.59]). No significant difference in cardiac index (CI) was found between BPA (MD = 0.40 L/min/m2 , 95% CI: [0.21, 0.58]) and riociguat (MD = 0.40 L/min/m2 , 95% CI: [0.26, 0.54]). The most common complications of BPA were pulmonary injury (0.3%-5.6%) and pulmonary edema (0.8%-28.6%). The most common adverse events of riociguat were headache, dizziness, hypotension and nasopharyngitis. CONCLUSIONS: Our meta-analysis indicates that BPA might be associated with greater improvements in exercise tolerance and pulmonary hemodynamics except for cardiac output and cardiac index than riociguat therapy. However, both of them were well tolerated.