Human bone marrow mesenchymal stem cell-derived extracellular vesicles restore Th17/Treg homeostasis in periodontitis via miR-1246

A state-of-the-art review of the recent advances in drug delivery systems for different therapeutic agents in periodontitis

Periodontitis (PD) is a chronic gum illness that may be hard to cure for a number of reasons, including the fact that no one knows what causes it, the side effects of anti-microbial treatment, and how various kinds of bacteria interact with one another. As a result, novel therapeutic approaches for PD treatment must be developed. Additionally, supplementary antibacterial regimens, including local and systemic medication administration of chemical agents, are necessary for deep pockets to assist with mechanical debridement of tooth surfaces. As our knowledge of periodontal disease and drug delivery systems (DDSs) grows, new targeted delivery systems like extracellular vesicles, lipid-based nanoparticles (NPs), metallic NPs, and polymer NPs have been developed. These systems aim to improve the targeting and precision of PD treatments while reducing the systemic side effects of antibiotics. Nanozymes, photodermal therapy, antibacterial metallic NPs, and traditional PD therapies have all been reviewed in this research. Medicinal herbs, antibiotics, photothermal therapy, nanozymes, antibacterial metallic NPs, and conventional therapies for PD have all been examined in this research. After that, we reviewed the key features of many innovative DDSs and how they worked for PD therapy. Finally, we have discussed the advantages and disadvantages of these DDSs.

Invisible appliance promotes bone reconstruction via modulating the periodontal immune microenvironment

OBJECTIVES

Recently, invisible appliances have become popular due to their aesthetics and comfort, but their impact on periodontal health in periodontitis patients has not been fully elucidated. The purpose of this study was to investigate the effectiveness of fixed and invisible appliance treatment for periodontitis in experimental rats while monitoring the dynamics of Th17/Treg cells and osteoclast-related cytokines during treatment.

METHODS

SD rats were randomly divided into six groups: control, periodontitis model, scaling-0 (basic treatment), no appliance, fixed appliance, and invisible appliance. After successful establishment of ligature-induced periodontitis, rats in the treatment groups were first subjected to supra/subgingival scaling and daily brushing for 2 weeks. Next, except rats in the scaling-0 group, the periodontitis rats were treated with uncorrected, fixed, or invisible appliance, respectively. The CEJ-AC was examined using micro-CT. Osteoclast activation was detected with TRAP staining. The proportion of Th17 and Treg cells was measured by flow cytometry. Subsequently, potential mechanisms were explored by detection of RORγt, Foxp3, RANKL, OPG, and pathogenic bacteria (Pg, Aa, and Tf). Finally, the association between Th17/Treg cells and osteoclast-related indicators as well as pathogenic bacteria was evaluated by correlation analysis.

RESULTS

Among the three treatments, invisible appliance treatment provided optimal results in controlling periodontal infection while promoting periodontal tissue repair. Specifically, in the early phase of treatment (3-7 days), orthodontic force exerted by the appliance stimulates osteoclast and Th17 cell activation by increasing RANKL and RORγt expression, thereby inducing osteoclast generation and accelerating the amount of tooth movement. In the later stages of treatment (7-21 days), Foxp3 and OPG levels gradually increased to induce the dominant role of Treg cells, controlling osteoclast generation and bone resorption. Meanwhile, the invisible appliance can maintain a low number of pathogenic bacteria during treatment. Finally, Th17 cells showed significant positive correlation with RANKL, Pg, osteoclast percentage, and CEJ-AC; Treg cells were positively correlated with RANKL and OPG; Th17/Treg ratio displayed positive correlation with RANKL/OPG or osteoclast percentage.

CONCLUSIONS

Invisible appliance has obvious advantages in periodontitis treatment, which can effectively improve periodontal condition and reduce inflammatory response.

The epigenetic landscape of mesenchymal stem cell and extracellular vesicle therapy

Mesenchymal stem cell (MSC) therapy shows great potential for treating tissue impairments and immune disorders. Epigenetic regulation is a core molecular signature that ensures long-lasting memory in MSC functional modulation and mediates therapeutic efficacy. Studies reveal that transplanted MSCs drive epigenetic changes in recipient cells, which contributes to restoration of organismal and microenvironmental homeostasis. Extracellular vesicles (EVs) derived from MSCs, including exosomes and apoptotic vesicles (apoVs), enable the transfer of epigenetic regulators, orchestrating intercellular epigenetic reprogramming and signaling modulation in both local and systemic microenvironments. Here, the epigenetic regulation of MSC and EV therapies is reviewed, together with current challenges, aiming to deepen the understanding of donor-recipient communication and inspire next-generation approaches to counteract tissue defects and diseases.

Regulatory T cells engineered with polyphenol-functionalized immunosuppressant nanocomplexes for rebuilding periodontal hard tissue under inflammation-challenged microenvironment

Global aging heightens the risk of oral disorders, among which periodontitis is the major cause of tooth loss in the aging population. The regeneration of damaged periodontal hard tissue is highly challenging due to the existence of the refractory local inflammation. Owing to the potent anti-inflammatory capabilities, regulatory T cells hold great promise in immunotherapies for tissue regeneration. However, the transferred regulatory T cells can alter their phenotypes and functions in local inflammatory milieu, significantly impairing their therapeutic efficacy. Herein, we introduce a novel regulatory T cell-based nanobiohybrid system bearing polyphenol-functionalized rapamycin nanocomplexes. The sustained in situ release of immunosuppressant rapamycin from the cell-attached nanocomplexes maintains the anti-inflammatory phenotype of regulatory T cells in the inflammatory milieu. The synergistic actions of the anti-inflammatory cytokines secreted and the immunosuppressant released guide a pro-resolving polarization of macrophages and enhance osteogenic differentiation of bone marrow-derived stromal cells. The stabilized phenotype of the regulatory T cells dramatically promoted the resolution of periodontal inflammation and the repair of the hard tissue (alveolar bone) in vivo. Overall, these studies highlight a potent regulatory T cell-based nanobiohybrid therapy to treat periodontitis by modulating periodontal immune microenvironment.

Therapeutic prospects of microRNAs derived from mesenchymal stem cell extracellular vesicles in rheumatoid arthritis: a comprehensive overview

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by inflammatory joint damage. Recent studies have focused on the significance of microRNAs (miRNAs) in the pathogenesis of RA. Mesenchymal stem cells (MSCs) have emerged as a potential therapeutic option for RA based on their regenerative and immunomodulatory properties. MSCs release extracellular vesicles (EVs) containing miRNAs that can modulate immune and inflammatory responses. This article provides a comprehensive overview of the current evidence on the existence of various MSCs-derived miRNAs involved in the pathophysiology, characterization, and treatment of RA. An overview of the miRNA profiles in MSC-EVs is provided, along with an examination of their impact on various cell types implicated in RA pathogenesis, including synovial fibroblasts, macrophages, and T cells. Furthermore, the therapeutic capability of MSC-EVs for miRNA-based therapies in RA is discussed. In total, this review can present an extensive view of the complex interaction between EVs and MSC-derived miRNAs in RA and thus suggest valuable strategies for developing new therapeutic approaches to target this debilitating disease.

Emerging roles of extracellular vesicles in oral and maxillofacial areas

The oral and maxillofacial region is a highly complex area composed of multiple tissue types and bears various critical functions of the human body. Diseases in this region pose significant diagnostic and management challenges; therefore, exploring new strategies for early diagnosis, targeted treatment, and tissue reconstruction is key to improving patient prognosis and quality of life. Extracellular vesicles are a group of heterogeneous lipid-bilayer membrane structures secreted by most cell types, including exosomes, microvesicles, and apoptotic bodies. Present in various body fluids and tissues, they act as messengers via the transfer of nucleic acids, proteins, and metabolites to recipient cells. To date, studies have revealed the different roles of extracellular vesicles in physiological or pathological processes, as well as applications in disease diagnosis, prognosis, and treatment. The importance and tissue specificity of the dental and maxillofacial tissues indicate that extracellular vesicles derived from this region are promising for further research. This paper reviews the published data on extracellular vesicles derived from cells, body fluids, and tissues in oral and maxillofacial regions, summarizes the latest advances in extracellular vesicles from extensive sources, and concludes with a focus on the current research progress and application prospects of engineered exosomes in oral science.

Mesenchymal stem cell-derived extracellular vesicles in periodontal bone repair

Periodontitis is a chronic inflammatory disease that destroys tooth-supporting structures and poses significant public health challenges due to its high prevalence and links to systemic health conditions. Traditional treatments are effective in reducing the inflammatory response and improving the clinical symptoms of periodontitis. However, these methods are challenging to achieve an ideal treatment effect in alveolar bone repair. Mesenchymal stem cells (MSCs) represent a potential alternative for the treatment of periodontal bone defects due to their self-renewal and differentiation capabilities. Recent research indicates that MSCs exert their effects primarily through paracrine mechanisms. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) serve as pivotal mediators in intercellular communication, transferring microRNAs (miRNAs), messenger RNAs (mRNAs), proteins, and cytokines to recipient cells, thereby emulating the therapeutic effects of MSCs. In periodontitis, MSC-EVs play a pivotal role in immunomodulation and bone remodeling, thereby facilitating periodontal bone repair. As a cell-free therapy, MSC-EVs demonstrate considerable clinical potential due to their specialized membrane structure, minimal immunogenicity, low toxicity, high biocompatibility, and nanoscale size. This review indicates that MSC-EVs represent a promising approach for periodontitis treatment, with the potential to overcome the limitations of traditional therapies and offer a more effective solution for bone repair in periodontal disease. In this review, we introduce MSC-EVs, emphasizing their mechanisms and clinical applications in periodontal bone repair. It synthesizes recent advances, existing challenges, and future prospects to present up-to-date information and novel techniques for periodontal regeneration and to guide the improvement of MSC-EV therapy in clinical practice.

Advances in the research of immunomodulatory mechanism of mesenchymal stromal/stem cells on periodontal tissue regeneration

Periodontal disease is a highly prevalent disease worldwide that seriously affects people's oral health, including gingivitis and periodontitis. Although the current treatment of periodontal disease can achieve good control of inflammation, it is difficult to regenerate the periodontal supporting tissues to achieve a satisfactory therapeutic effect. In recent years, due to the good tissue regeneration ability, the research on Mesenchymal stromal/stem cells (MSCs) and MSC-derived exosomes has been gradually deepened, especially its ability to interact with the microenvironment of the body in the complex immunoregulatory network, which has led to many new perspectives on the therapeutic strategies for many diseases. This paper systematically reviews the immunomodulatory (including bone immunomodulation) properties of MSCs and their role in the periodontal inflammatory microenvironment, summarizes the pathways and mechanisms by which MSCs and MSC-EVs have promoted periodontal regeneration in recent years, lists potential areas for future research, and describes the issues that should be considered in future basic research and the direction of development of "cell-free therapies" for periodontal regeneration.

A new strategy for drug delivery systems in oral diseases using stem cell-derived extracellular vesicles: review and new perspectives

Extracellular vesicles (EVs) are membrane vesicles derived from cells and serve as an endogenous mechanism for intercellular communication. Since the discovery of their capacity to effectively transfer biological information, their potential as drug delivery vehicles has garnered significant scientific interest. Particularly, EVs derived from mesenchymal cells (MSC-EVs) have emerged as a highly promising method for drug delivery. They can transport bioactive molecules, such as nucleic acids, lipids, and proteins, and possess the ability to modulate immune responses, transmit information, and target specific cells. EVs offer several advantages over conventional drug delivery systems, including their capacity to traverse natural barriers, inherent cell targeting capabilities, and stability in circulation. Compared to their parent cells, EVs exhibit low immunogenicity, ease of storage and transport, and a reduced risk of tumorigenesis. The diagnosis and treatment of oral diseases often involve invasive measures, and MSC-EVs have demonstrated initial efficacy in oral disease treatment. This review explores the application of MSC-EVs in maxillofacial tissue regeneration, periodontitis, temporomandibular joint osteoarthritis, Sjögren's Syndrome, oral cancer, and other oral diseases. Additionally, it outlines potential future directions for the development of MSC-EVs. This review aims to provide a comprehensive understanding of MSC-EVs in oral disease treatment and to stimulate interest in their applications for targeted drug delivery.

Advances in the roles and mechanisms of mesenchymal stem cell derived microRNAs on periodontal tissue regeneration

Periodontitis is one of the most prevalent oral diseases leading to tooth loss in adults, and is characterized by the destruction of periodontal supporting structures. Traditional therapies for periodontitis cannot achieve ideal regeneration of the periodontal tissue. Mesenchymal stem cells (MSCs) represent a promising approach to periodontal tissue regeneration. Recently, the prominent role of MSCs in this context has been attributed to microRNAs (miRNAs), which participate in post-transcriptional regulation and are crucial for various physiological and pathological processes. Additionally, they function as indispensable elements in extracellular vesicles, which protect them from degradation. In periodontitis, MSCs-derived miRNAs play a pivotal role in cellular proliferation and differentiation, angiogenesis of periodontal tissues, regulating autophagy, providing anti-apoptotic effects, and mediating the inflammatory microenvironment. As a cell-free strategy, their small size and ability to target related sets of genes and regulate signaling networks predispose miRNAs to become ideal candidates for periodontal tissue regeneration. This review aims to introduce and summarize the potential functions and mechanisms of MSCs-derived miRNAs in periodontal tissue repair and regeneration.

HuMSC-EVs Protect Endothelial Cells Against Hypoxia/Reoxygenation Injury by Inhibiting the Pannexin 1/p38-MAPK Pathway

Vascular endothelial cell dysfunction plays an important role in myocardial ischemia-reperfusion (I/R) injury, and pannexin 1 (Panx1), an ATP-permeable channel, is closely associated with the pathophysiological processes of I/R injury. The purpose of this study was to investigate the protective effects of human umbilical cord mesenchymal stromal cell-derived extracellular vesicles (HuMSC-EVs) and the underlying mechanism in a model of I/R injury. For the cellular model of I/R injury, human umbilical vein endothelial cells (HuVECs) were exposed to hypoxia/reoxygenation (H/R) conditions. The model cells were then treated with HuMSC-EVs, and the effects on cell survival and specific signaling activities were observed. The results showed that after H/R exposure, Panx1 expression and other markers of cellular damage were increased in HuVECs. However, treatment with HuMSC-EVs inhibited the H/R-induced increase in Panx1 expression and improved HuVEC survival. Mechanistically, HuMSC-EVs were found to inhibit the p38 mitogen-activated protein kinase (MAPK)-dependent apoptosis pathway, as evidenced by increased Bcl2 expression and reductions in p38 MAPK phosphorylation, Bax expression, and cleaved-caspase 3 expression. Together our data suggest that HuMSC-EVs alleviate H/R-induced apoptosis among HuVECs by inhibiting activity of the Panx1/p38-MAPK-dependent apoptosis pathway.

The oral-gut microbiome axis in inflammatory bowel disease: from inside to insight

Inflammatory bowel disease (IBD) is an idiopathic and persistent inflammatory illness of the bowels, leading to a substantial burden on both society and patients due to its high incidence and recurrence. The pathogenesis of IBD is multifaceted, partly attributed to the imbalance of immune responses toward the gut microbiota. There is a correlation between the severity of the disease and the imbalance in the oral microbiota, which has been discovered in recent research highlighting the role of oral microbes in the development of IBD. In addition, various oral conditions, such as angular cheilitis and periodontitis, are common extraintestinal manifestations (EIMs) of IBD and are associated with the severity of colonic inflammation. However, it is still unclear exactly how the oral microbiota contributes to the pathogenesis of IBD. This review sheds light on the probable causal involvement of oral microbiota in intestinal inflammation by providing an overview of the evidence, developments, and future directions regarding the relationship between oral microbiota and IBD. Changes in the oral microbiota can serve as markers for IBD, aiding in early diagnosis and predicting disease progression. Promising advances in probiotic-mediated oral microbiome modification and antibiotic-targeted eradication of specific oral pathogens hold potential to prevent IBD recurrence.

Exploration of altered miRNA expression and function in MSC-derived extracellular vesicles in response to hydatid antigen stimulation

Background

Hydatid disease is caused by Echinococcus parasites and can affect various tissues and organs in the body. The disease is characterized by the presence of hydatid cysts, which contain specific antigens that interact with the host's immune system. Mesenchymal stem cells (MSCs) are pluripotent stem cells that can regulate immunity through the secretion of extracellular vesicles (EVs) containing microRNAs (miRNAs).

Methods

In this study, hydatid antigens were isolated from sheep livers and mice peritoneal cavities. MSCs derived from mouse bone marrow were treated with different hydatid antigens, and EVs were isolated and characterized from the conditioned medium of MSCs. Small RNA library construction, miRNA target prediction, and differential expression analysis were conducted to identify differentially expressed miRNAs. Functional enrichment and network construction were performed to explore the biological functions of the target genes. Real-time PCR and Western blotting were used for miRNA and gene expression verification, while ELISA assays quantified TNF, IL-1, IL-6, IL-4, and IL-10 levels in cell supernatants.

Results

The study successfully isolated hydatid antigens and characterized MSC-derived EVs, demonstrating the impact of antigen concentration on MSC viability. Key differentially expressed miRNAs, such as miR-146a and miR-9-5p, were identified, with functional analyses revealing significant pathways like Endocytosis and MAPK signaling associated with these miRNAs' target genes. The miRNA-HUB gene regulatory network identified crucial miRNAs and HUB genes, such as Traf1 and Tnf, indicating roles in immune modulation and osteogenic differentiation. Protein-protein interaction (PPI) network analysis highlighted central HUB genes like Akt1 and Bcl2. ALP activity assays confirmed the influence of antigens on osteogenic differentiation, with reduced ALP activity observed. Expression analysis validated altered miRNA and chemokine expression post-antigen stimulation, with ELISA analysis showing a significant reduction in CXCL1 expression in response to antigen exposure.

Conclusion

This study provides insights into the role of MSC-derived EVs in regulating parasite immunity. The findings suggest that hydatid antigens can modulate the expression of miRNAs in MSC-derived EVs, leading to changes in chemokine expression and osteogenic capacity. These findings contribute to a better understanding of the immunomodulatory mechanisms involved in hydatid disease and provide potential therapeutic targets for the development of new treatment strategies.

The Genetic Aspects of Periodontitis Pathogenesis and the Regenerative Properties of Stem Cells

Periodontitis (PD) is a prevalent and chronic inflammatory disease with a complex pathogenesis, and it is associated with the presence of specific pathogens, such as Porphyromonas gingivalis. Dysbiosis and dysregulated immune responses ultimately lead to chronic inflammation as well as tooth and alveolar bone loss. Multiple studies have demonstrated that genetic polymorphisms may increase the susceptibility to PD. Furthermore, gene expression is modulated by various epigenetic mechanisms, such as DNA methylation, histone modifications, or the activity of non-coding RNA. These processes can also be induced by PD-associated pathogens. In this review, we try to summarize the genetic processes that are implicated in the pathogenesis of PD. Furthermore, we discuss the use of these mechanisms in diagnosis and therapeutic purposes. Importantly, novel treatment methods that could promote tissue regeneration are greatly needed in PD. In this paper, we also demonstrate current evidence on the potential use of stem cells and extracellular vesicles to stimulate tissue regeneration and suppress inflammation. The understanding of the molecular mechanisms involved in the pathogenesis of PD, as well as the impact of PD-associated bacteria and stem cells in these processes, may enhance future research and ultimately improve long-term treatment outcomes.