Multifunctional Lithium-Doped Mesoporous Nanoparticles for Effective Dentin Regeneration in vivo.

Introduction: Effective infection control without irritating the pulp tissue is the key to successful vital pulp therapy. Developing a novel antibacterial biomaterial that promotes dentin regeneration for pulp capping is thus a promising strategy for enhancing vital pulp therapy. Methods: Lithium-doped mesoporous nanoparticles (Li-MNPs) were synthesized using an alkali-catalyzed sol-gel method. The particle size, elemental distribution, surface morphology, pore structure, and ion release from Li-MNPs were measured. Human dental pulp stem cells (hDPSCs) and Streptococcus mutans (S. mutans) were used to evaluate the biological effects of Li-MNPs. In addition, a dental pulp exposure mouse model was used to evaluate the regenerative effects of Li-MNPs. Results: Li-MNPs had a larger surface area (221.18 m2/g), a larger pore volume (0.25 cm3/g), and a smaller particle size (520.92 ± 35.21 nm) than MNPs. The in vitro investigation demonstrated that Li-MNPs greatly enhanced the biomineralization and odontogenic differentiation of hDPSCs through the Wnt/ß-catenin signaling pathway. Li-MNPs showed a strong antibacterial effect on S. mutans. As expected, Li-MNPs significantly promoted dentin regeneration in situ and in vivo. Conclusion: Li-MNPs promoted dentin regeneration and inhibited S. mutans growth, implying a possible application as a pulp capping agent in vital pulp therapy.

Selenium-Doped Mesoporous Bioactive Glass Regulates Macrophage Metabolism and Polarization by Scavenging ROS and Promotes Bone Regeneration In Vivo.

Bone regeneration is complex and involves multiple cells and systems, with macrophage-mediated immune regulation being critical for the development and regulation of inflammation, angiogenesis, and osteogenesis. Biomaterials with modified physical and chemical properties (e.g., modified wettability and morphology) effectively regulate macrophage polarization. This study proposes a novel approach to macrophage-polarization induction and -metabolism regulation through selenium (Se) doping. We synthesized Se-doped mesoporous bioactive glass (Se-MBG) and demonstrated its macrophage-polarization regulation toward M2 and its enhancement of the macrophage oxidative phosphorylation metabolism. The underlying mechanism is the effective scavenging of excessive intracellular reactive oxygen species (ROS) by the Se-MBG extracts through the promotion of peroxide-scavenging enzyme glutathione peroxidase 4 expression in the macrophages; this, in turn, improves the mitochondrial function. Printed Se-MBG scaffolds were implanted into rats with critical-sized skull defects to evaluate their immunomodulatory and bone regeneration capacity in vivo. The Se-MBG scaffolds demonstrated excellent immunomodulatory function and robust bone regeneration capacity. Macrophage depletion with clodronate liposomes impaired the Se-MBG-scaffold bone regeneration effect. Se-mediated immunomodulation, which targets ROS scavenging to regulate macrophage metabolic profiles and mitochondrial function, is a promising concept for future effective biomaterials for bone regeneration and immunomodulation.

The role of PIWI-interacting RNA in naringin pro-angiogenesis by targeting HUVECs.

Angiogenesis is a biological process in which resting endothelial cells start proliferating, migrating and forming new blood vessels. Angiogenesis is particularly important in the repair of bone tissue defects. Naringin (NG) is the main active monomeric component of traditional Chinese medicine, which has various biological activities, such as anti-osteoporosis, anti-inflammatory, blood activation and microcirculation improvement. At present, the mechanism of naringin in the process of angiogenesis is not clear. PIWI protein-interacting RNA (piRNA) is a small noncoding RNA (sncRNA) that has the functions of regulating protein synthesis, regulating the structure of chromatin and the genome, stabilizing mRNA and others. Several studies have demonstrated that piRNAs can mediate the angiogenesis process. Whether naringin can interfere with the process of angiogenesis by regulating piRNAs and related target genes deserves further exploration. Thus, the purpose of this study was to validate the potential angiogenic and bone regeneration properties and related mechanisms of naringin both in vivo and in vitro.

Association between chronic obstructive pulmonary disease and periodontitis: The common role of innate immune cells?

Innate immune cells are of broad interest in a variety of diseases. These cells include neutrophils, macrophages, dendritic cells and mast cells, etc. Innate immune cells are often mentioned in inflammatory diseases as the first line of defense against pathogens' invasion. As chronic obstructive pulmonary disease and periodontitis are inflammatory diseases, innate immune cells play an important role in the development of both diseases. COPD and periodontitis are common epidemic diseases with a very high prevalence, thus affecting a large number of people and also reducing the quality of life of patients. In addition, epidemiological studies suggested a link between the two, creating a co-morbid burden, but the mechanism of the link is yet to be explained. This article discusses the possible mechanism of the link between the two diseases in terms of innate immune cells and discusses possible future targeted therapies that could alleviate the burden on patients.

The role of Th17 cells: explanation of relationship between periodontitis and COPD?

Periodontitis and chronic obstructive pulmonary disease (COPD) are chronic inflammatory diseases with common risk factors, such as long-term smoking, age, and social deprivation. Many observational studies have shown that periodontitis and COPD are correlated. Moreover, they share a common pathophysiological process involving local accumulation of inflammatory cells and cytokines and damage of soft tissues. The T helper 17 (Th17) cells and the related cytokines, interleukin (IL)-17, IL-22, IL-1ß, IL-6, IL-23, and transforming growth factor (TGF)-ß, play a crucial regulatory role during the pathophysiological process. This paper reviewed the essential roles of Th17 lineage in the occurrence of periodontitis and COPD. The gaps in the study of their common pathological mechanism were also evaluated to explore future research directions. Therefore, this review can provide study direction for the association between periodontitis and COPD and new ideas for the clinical diagnosis and treatment of the two diseases.

The Role of Oral Microbiota in Chronic Obstructive Pulmonary Disease.

Studies have shown that oral microbiota dysbiosis affects patients' lung function, promoting the development and acute exacerbation of chronic obstructive pulmonary disease (COPD). In this paper, we review the mechanisms potentially linking COPD with periodontitis. Oral microbiota enters the respiratory system through clinical microaspiration to aggravate lung microbiota dysbiosis and induce lung injury by entering the respiratory tract directly. Appropriate interventions for dysbiosis such as periodontal therapy or oral microbial transplantation may prevent the progression of COPD.

Drug-loading three-dimensional scaffolds based on hydroxyapatite-sodium alginate for bone regeneration.

Bone tissue engineering is a promising approach for tackling clinical challenges. Osteoprogenitor cells, osteogenic factors, and osteoinductive/osteoconductive scaffolds are employed in bone tissue engineering. However, scaffold materials remain limited due to their source, low biocompatibility, and so on. In this study, a composite hydrogel scaffold composed of hydroxyapatite (HA) and sodium alginate (SA) was manufactured using three-dimensional printing. Naringin (NG) and calcitonin-gene-related peptide (CGRP) were used as osteogenic factors in the fabrication of drug-loaded scaffolds. Investigation using animal experiments, as well as scanning electron microscopy, cell counting kit-8 testing, alkaline phosphatase staining, and alizarin red-D staining of bone marrow mesenchymal stem cell culture showed that the three scaffolds displayed similar physicochemical properties and that the HA/SA/NG and HA/SA/CGRP scaffolds displayed better osteogenesis than that of the HA/SA scaffold. Thus, the HA/SA scaffold could be a biocompatible material with potential applications in bone regeneration. Meanwhile, NG and CGRP doping could result in better and more positive proliferation and differentiation.