It remains an obstacle to induce the regeneration of hard dentin tissue in clinical settings. To overcome this, a P(VDF‐TrFE) piezoelectric film with 2 wt% SrCl₂ addition is designed. The biofilm shows a high flexibility, a harmonious biocompatibility, and a large piezoelectric d₃₃ coefficient of 14 pC N⁻¹, all contributing to building an electric microenvironment that favor the recruitment of dental pulp stem cells (DPSCs) and their differentiation into odontoblasts during normal chewing, speaking, etc. On the other hand, the strontium ions can be gradually released from the film, thus promoting DPSC odonto‐differentiation. In vivo experiments also demonstrate that the film induces the release of dentin minerals and regeneration of dentin tissue. In the large animal dentin defect models, this piezoelectric film induces in situ dentin tissue formation effectively over a period of three months. This study illustrates a therapeutic potential of the piezoelectric film to improve dentin tissue repair in clinical settings.

Bone morphogenetic protein (BMP-2) has been approved by the FDA to promote bone regeneration, but uncertain osteogenic effect and dose-dependent side effects may occur. Osteoimmunomodulation plays an important role in growth factor-based osteogenesis. Here, we explored how proinflammatory signals affect the dose-dependent osteogenic potential of BMP-2. We observed that the expression level of local IL-1β did not increase with the dose of BMP-2 in the mouse osteogenesis model. A low dose of BMP-2 could not promote new bone formation, but trigger the release of IL-1β from M1 macrophages. As the dose of BMP-2 increased, the IL-1β expression and M1 infiltration in local microenvironment were inhibited by IL-1Ra from MSCs under osteogenic differentiation induced by BMP-2, and new bone tissues formed, even excessively. Anti-inflammatory drugs (Dexamethasone, Dex) promoted osteogenesis via inhibiting M1 polarization and enhancing BMP-2-induced MSC osteo-differentiation. Thus, we suggest that the osteogenic effect of BMP-2 involves macrophage-MSC interaction that is dependent on BMP-2 dose and based on IL-1R1 ligands, including IL-1β and IL-1Ra. The dose of BMP-2 could be reduced by introducing immunoregulatory strategies.

Citrus reticulatae pericarpium (CRP) is regarded as a valuable functional food in many countries due to its pharmacological activities and unique aroma. In this study, CRP was treated by different A. niger to accelerate aging. Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) fingerprinting was adopted to rapidly and comprehensively evaluate the flavor compounds of CRP and to identify their dynamic changes at different storage time. Results revealed that the hesperidin content of DOL groups reduced more clearly than other groups during storage. A total of 134 volatile flavor compounds were identified. The volatile organic compounds (VOCs) showed that the lemon, sweet with the musk aroma of CRP, changed to apple, pineapple, and coffee odors during storage. The principal component analysis (PCA) and fingerprint similarity analysis (FSA) results showed that the CRP was clearly distinguished at different storage time. DOL-3 and DOS-6 differ the most from the DOW-3,6, respectively. This work provided helpful information for accelerating the aging of CRP and has great potential for industrial application.

Bone regeneration has become a research hotspot and therapeutic target in the field of bone and joint medicine. Stem cell-based therapy aims to promote endogenous regeneration and improves therapeutic effects and side-effects of traditional reconstruction of significant bone defects and disorders. Human amniotic mesenchymal stem cells (hAMSCs) are seed cells with superior paracrine functions on immune-regulation, anti-inflammation, and vascularized tissue regeneration. The present review summarized the source and characteristics of hAMSCs and analyzed their roles in tissue regeneration. Next, the therapeutic effects and mechanisms of hAMSCs in promoting bone regeneration of joint diseases and bone defects. Finally, the clinical application of hAMSCs from current clinical trials was analyzed. Although more studies are needed to confirm that hAMSC-based therapy to treat bone diseases, the clinical application prospect of the approach is worth investigating.