Wrinkled topography regulates osteogenesis via autophagy-mediated Wnt/β-catenin signaling pathway in MC3T3-E1 cells

Fabrication of novel nanofiber composed of gelatin/alginate with zirconium oxide NPs regulate orthodontic progression of cartilage degeneration on Wnt/β-catenin signaling axis in MC3T3-E1 cells

Natural macromolecules like alginate and gelatin are employed to create medication delivery systems that are both safe and effective. Zirconium nanoparticles (ZrO2 NPs) have been proposed as a means of enhancing the alginate-gelatin hydrogel's physical and biological properties. This study combines the synthesis of the biopolymers gelatin and alginate nanofibers with nanoparticles of zirconium oxide (GA/NF- ZrO2 NPs). UV, XRD, FTIR, and SEM were used to characterize the synthesized nanofibers. The expression of osteogenic genes was analyzed by western blotting and qualitative real-time polymerase chain reaction (qRT-PCR). Based on our findings, MC3T3-E1 cells are performed for cell viability, apoptosis and reactive oxygen species production by GA/NF- ZrO2 NPs through the Wnt/β-catenin signaling pathway. Cell migration was accelerated at 75 μg/mL concentration after 24 h of damage in a scratch wound healing assay. Proliferation of the MC3T3-E1 cell line was also detected. GA/NF-ZrO2 NPs influenced the osteogenic variation of MC3T3-E1 cells by inducing autophagy. Furthermore, the impact of obstruction on the temporomandibular joint (TMJ) is a subject of ongoing discussion and analysis within the context of animal models. Coordinated GA/NF-ZrO2 NPs on biomaterial nanofibers could be used to introduce physical signals for modifying MC3T3-E1 responds for orthodontic engineering constructs.

Advances in the roles of ATF4 in osteoporosis

Osteoporosis (OP) is characterized by reduced bone mass, decreased strength, and enhanced bone fragility fracture risk. Activating transcription factor 4 (ATF4) plays a role in cell differentiation, proliferation, apoptosis, redox balance, amino acid uptake, and glycolipid metabolism. ATF4 induces the differentiation of bone marrow mesenchymal stem cells (BM-MSCs) into osteoblasts, increases osteoblast activity, and inhibits osteoclast formation, promoting bone formation and remodeling. In addition, ATF4 mediates the energy metabolism in osteoblasts and promotes angiogenesis. ATF4 is also involved in the mediation of adipogenesis. ATF4 can selectively accumulate in osteoblasts. ATF4 can directly interact with RUNT-related transcription factor 2 (RUNX2) and up-regulate the expression of osteocalcin (OCN) and osterix (Osx). Several upstream factors, such as Wnt/β-catenin and BMP2/Smad signaling pathways, have been involved in ATF4-mediated osteoblast differentiation. ATF4 promotes osteoclastogenesis by mediating the receptor activator of nuclear factor κ-B (NF-κB) ligand (RANKL) signaling. Several agents, such as parathyroid (PTH), melatonin, and natural compounds, have been reported to regulate ATF4 expression and mediate bone metabolism. In this review, we comprehensively discuss the biological activities of ATF4 in maintaining bone homeostasis and inhibiting OP development. ATF4 has become a therapeutic target for OP treatment.