Exosome secreted by human gingival fibroblasts in radiation therapy inhibits osteogenic differentiation of bone mesenchymal stem cells by transferring miR-23a

Bone marrow mesenchymal stem cells-derived exosomes promote spinal cord injury repair through the miR-497-5p/TXNIP/NLRP3 axis

Bone marrow mesenchymal stem cells (BMSCs) indicate a repairing prospect to treat spinal cord injury, a major traumatic disease. This study investigated the repair effect of bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exos) on spinal cord injury. BMSCs were collected to extract BMSC-Exos which were identified by different means. The SCI model of rats was established, the motor behavior was scored by BBB field test, and the spinal cord tissues were separated and stained by HE, Nissl, and Tunel, respectively, as well as analyzed to measure inflammatory and oxidative stress responses. PC12 cells were co-cultured with Exos and analyzed by CCK-8 and flow cytometry to measure cell proliferation and apoptosis. BMSC-Exos improved SCI in rats with the recovery of motor function, alleviation of pathological conditions, and reduction of apoptosis, inflammatory responses, and oxidative stress. BMSC-Exos increased miR-497-5p expression, and miR-497-5p overexpression strengthened the protective effect of BMSC-Exos on SCI. miR-497-5p targeted inactivation of TXNIP/NLRP3 pathway. TXNIP saved the repair effect of miR-497-5p-carrying BMSC-Exos on SCI rats. miR-497-5p-carrying BMSC-Exos alleviated apoptosis and induced proliferation of H2O2-treated PC12 cells. BMSC-Exos promote SCI repair via the miR-497-5p/TXNIP/NLRP3 axis, which may be a target for alleviating SCI-associated nerve damage.

Mesenchymal Stem Cells and Their Extracellular Vesicles Are a Promising Alternative to Antibiotics for Treating Sepsis

Sepsis is a life-threatening disease caused by the overwhelming response to pathogen infections. Currently, treatment options for sepsis are limited to broad-spectrum antibiotics and supportive care. However, the growing resistance of pathogens to common antibiotics complicates treatment efforts. Excessive immune response (i.e., cytokine storm) can persist even after the infection is cleared. This overactive inflammatory response can severely damage multiple organ systems. Given these challenges, managing the excessive immune response is critical in controlling sepsis progression. Therefore, Mesenchymal stem cells (MSCs), with their immunomodulatory and antibacterial properties, have emerged as a promising option for adjunctive therapy in treating sepsis. Moreover, MSCs exhibit a favorable safety profile, as they are eventually eliminated by the host's immune system within several months post-administration, resulting in minimal side effects and have not been linked to common antibiotic therapy drawbacks (i.e., antibiotic resistance). This review explores the potential of MSCs as a personalized therapy for sepsis treatment, clarifying their mechanisms of action and providing up-to-date technological advancements to enhance their protective efficacy for patients suffering from sepsis and its consequences.

Extracellular vesicles and the "six Rs" in radiotherapy

Over half of patients with cancer receive radiation therapy during the course of their disease. Decades of radiobiological research have identified 6 parameters affecting the biological response to radiation referred to as the 6 "Rs": Repair, Radiosensitivity, Repopulation, Redistribution, Reoxygenation, and Reactivation of the anti-tumour immune response. Extracellular Vesicles (EVs) are small membrane-bound particles whose multiple biological functions are increasingly documented. Here we discuss the evidence for a role of EVs in the orchestration of the response of cancer cells to radiotherapy. We highlight that EVs are involved in DNA repair mechanisms, modulation of cellular sensitivity to radiation, and facilitation of tumour repopulation. Moreover, EVs influence tumour reoxygenation dynamics, and play a pivotal role in fostering radioresistance. Last, we examine how EV-related strategies could be translated into novel strategies aimed at enhancing the efficacy of radiation therapy against cancer.

Adipogenic differentiation effect of human periodontal ligament stem cell initial cell density on autologous cells and human bone marrow stromal cells

Stem cells demonstrate differentiation and regulatory functions. In this discussion, we will explore the impacts of cell culture density on stem cell proliferation, adipogenesis, and regulatory abilities. This study aimed to investigate the impact of the initial culture density of human periodontal ligament stem cells (hPDLSCs) on the adipogenic differentiation of autologous cells. Our findings indicate that the proliferation rate of hPDLSCs increased with increasing initial cell density (0.5-8 × 104 cells/cm2). After adipogenic differentiation induced by different initial cell densities of hPDLSC, we found that the mean adipose concentration and the expression levels of lipoprotein lipase (LPL), CCAAT/enhancer binding protein α (CEBPα), and peroxisome proliferator-activated receptor γ (PPAR-γ) genes all increased with increasing cell density. To investigate the regulatory role of hPDLSCs in the adipogenic differentiation of other cells, we used secreted exocrine vesicles derived from hPDLSCs cultivated at different initial cell densities of 50 μg/mL to induce the adipogenic differentiation of human bone marrow stromal cells. We also found that the mean adipose concentration and expression of LPL, CEBPα, and PPARγ genes increased with increasing cell density, with an optimal culture density of 8 × 104 cells/cm2. This study provides a foundation for the application of adipogenic differentiation in stem cells.

Exosomal non-coding RNAs: Emerging insights into therapeutic potential and mechanisms in bone healing

Exosomes are nano-sized extracellular vesicles (EVs) released by diverse types of cells, which affect the functions of targeted cells by transporting bioactive substances. As the main component of exosomes, non-coding RNA (ncRNA) is demonstrated to impact multiple pathways participating in bone healing. Herein, this review first introduces the biogenesis and secretion of exosomes, and elucidates the role of the main cargo in exosomes, ncRNAs, in mediating intercellular communication. Subsequently, the potential molecular mechanism of exosomes accelerating bone healing is elucidated from the following four aspects: macrophage polarization, vascularization, osteogenesis and osteoclastogenesis. Then, we systematically introduce construction strategies based on modified exosomes in bone regeneration field. Finally, the clinical trials of exosomes for bone healing and the challenges of exosome-based therapies in the biomedical field are briefly introduced, providing solid theoretical frameworks and optimization methods for the clinical application of exosomes in orthopedics.

Ambra1 in exosomes secreted by HK-2 cells damaged by supersaturated oxalate induce mitophagy and autophagy-ferroptosis in normal HK-2 cells to participate in the occurrence of kidney stones

Injury to the renal tubular epithelium has emerged as a leading factor underlying the formation of kidney stones. Indeed, epithelial cell damage contributes to the adherence and aggregation of crystals, thereby accelerating the formation of renal stones. Meanwhile, exosomes play an instrumental role in cellular communication, including DNA, RNA, mRNA, etc. In this study, homogenous cells were treated with exosomes derived from damaged cells in an attempt to establish "positive feedback" of cell damage, and the desired results were achieved. To begin, a serum-free medium and supersaturated concentrations of oxalate were added to the HK-2 cell line, and then exosomes were isolated from the two groups for analysis and comparison, and the autophagy-related gene Ambra1 (autophagy and beclin-1 regulator 1) was detected. Subsequently, normal HK-2 cells were treated with exosomes, and the related indexes of autophagy, ferroptosis and mitophagy were determined. Thereafter, Ambra1 was knocked down in exosome-derived HK-2 cells, resulting in the down-regulation of Ambra1 expression in exosomes produced by HK-2 cells following oxalate intervention. Thereafter, the ability of exosomes to stimulate autophagy, mitophagy and ferroptosis was re-evaluated in HK-2 cells after Ambra1 knockdown. The results corroborated that exosomes secreted by oxalate-treated HK-2 can directly elevate autophagy, ferroptosis and mitophagy levels in normal cells, and this effect was significantly mitigated following Ambra1 knockdown within exosomes. Meanwhile, exosomes-induced autophagy and ferroptosis were alleviated after knockdown of beclin-1 in recipient HK-2 cells. These results further suggest that beclin-1 plays a critical role in the process of exosome-induced autophagy-ferroptosis.

ATG7-mediated autophagy protects human gingival myofibroblasts from irradiation-induced apoptosis

BACKGROUND

Apoptosis resistance of myofibroblasts is critical in pathology of irradiation-induced fibrosis and osteoradionecrosis of the jaw (ORNJ). However, molecular mechanism of apoptosis resistance induced by irradiation in oral myofibroblasts remains largely obscure.

METHODS

Matched ORNJ fibroblasts and normal fibroblasts pairs from gingival were primarily cultured, and myofibroblast markers of α-SMA and FAP were evaluated by qRT-PCR and western blot. CCK8 assay and flow cytometric analysis were performed to investigate the cell viability and apoptosis under irradiation treatment. Autophagy-related protein LC3 and ATG7, and punctate distribution of LC3 localization were further detected. After inhibition of autophagy with inhibitor CQ and 3-MA, as well as transfected ATG7-siRNA, cell viability and apoptosis of ORNJ and normal fibroblasts were further assessed.

RESULTS

Compared with normal fibroblasts, ORNJ fibroblasts exhibited significantly higher α-SMA and FAP expression, increased cell, viability and decreased apoptosis under irradiation treatment. LC3-II and ATG7 were up-regulated in ORNJ fibroblasts with irradiation stimulation. After inhibition of irradiation-induced autophagic flux with lysosome inhibitor CQ, LC3-II protein was accumulated and punctate distribution of LC3 localization was increased in ORNJ fibroblasts. Moreover, autophagy inhibitor CQ and 3-MA enhanced the irradiation-induced apoptosis but inhibited viability of ORNJ fibroblasts. Silencing ATG7 with siRNA could obviously weaken irradiation-induced LC3-II expression, and promoted irradiation-induced apoptosis of ORNJ fibroblasts. After knockdown of ATG7, finally, p-AKT(Ser473) and p-mTOR(Ser2448) levels of ORNJ fibroblasts were significantly increased under irradiation.

CONCLUSION

Compared with normal fibroblasts, human gingival myofibroblasts are resistant to irradiation-induced apoptosis via autophagy activation. Silencing ATG7 may evidently inhibit activation of autophagy, and promote apoptosis of gingival myofibroblasts via Akt/mTOR pathway.

The Progress in Reconstruction of Mandibular Defect Caused by Osteoradionecrosis

Osteoradionecrosis (ORN) is described as a disease with exposed, nonviable bone that fails to heal spontaneously or by means of conservative treatment after radiotherapy in at least 3 months. Though traditional theories in the early stage including hypoxic-hypocellular-hypovascular and fibro-atrophic in addition to new findings such as ferroptosis were put forward to explain the mechanisms of the osteoradionecrosis, the etiology of ORN is still unclear. With the high rate of occurrence in the head and neck area, especially in the mandible, this disease can disrupt the shape and function of the irradiated area, leading to a clinical presentation ranging from stable small areas of asymptomatic exposed bone to severe progressive necrosis. In severe cases, patients may experience pain, xerostomia, dysphagia, facial fistulas, and even a jaw defect. Consequently, sequence therapy and sometimes extensive surgery and reconstructions are needed to manage these sequelae. Treatment options may include pain medication, antibiotics, the removal of sequesters, hyperbaric oxygen therapy, segmental resection of the mandible, and free flap reconstruction. Microanastomosed free-flaps are considered to be promising choice for ORN reconstruction in recent researches, and new methods including three-dimensional (3-D) printing, pentoxifylline, and amifostine are used nowadays in trying increase the success rates and improve quality of the reconstruction. This review summarizes the main research progress in osteoradionecrosis and reconstruction treatment of osteoradionecrosis with mandibular defect.

MSC-Exos: Important active factor of bone regeneration

Bone defect and repair is a common but difficult problem in restorative and reconstructive surgery. Bone tissue defects of different sizes caused by different reasons bring functional limitations and cosmetic deformities to patients. Mesenchymal stem cells (MSC), a major hotspot in the field of regeneration in recent years, have been widely used in various studies on bone tissue regeneration. Numerous studies have shown that the bone regenerative effects of MSC can be achieved through exosome-delivered messages. Although its osteogenic mechanism is still unclear, it is clear that MSC-Exos can directly or indirectly support the action of bone regeneration. It can act directly on various cells associated with osteogenesis, or by carrying substances that affect cellular activators or the local internal environment in target cells, or it can achieve activation of the osteogenic framework by binding to materials. Therefore, this review aims to summarize the types and content of effective contents of MSC-Exos in bone regeneration, as well as recent advances in the currently commonly used methods to enable the binding of MSC-Exos to the framework and to conclude that MSC-Exos is effective in promoting osteogenesis.

Mesenchymal Stem Cell-Derived Extracellular Vesicles: The Novel Therapeutic Option for Regenerative Dentistry

Dental mesenchymal stem cells (MSCs) are characterized by unlimited self-renewal ability and high multidirectional differentiation potential. Since dental MSCs can be easily isolated and exhibit a high capability to differentiate into odontogenic cells, they are considered as attractive therapeutic agents in regenerative dentistry. Recently, MSC-derived extracellular vesicles (MSC-EVs) have attracted widespread attention as carriers for cell-free therapy due to their potential functions. Many studies have shown that MSC-EVs can mediate microenvironment at tissue damage site, and coordinate the regeneration process. Additionally, MSC-EVs can mediate intercellular communication, thus affecting the phenotypes and functions of recipient cells. In this review, we mainly summarized the types of MSCs that could be potentially applied in regenerative dentistry, the possible molecular cargos of MSC-EVs, and the major effects of MSC-EVs on the therapeutic induction of osteogenic differentiation.

Application of exosome-derived noncoding RNAs in bone regeneration: Opportunities and challenges

With advances in the fields of regenerative medicine, cell-free therapy has received increased attention. Exosomes have a variety of endogenous properties that provide stability for molecular transport across biological barriers to cells, as a form of cell-to-cell communication that regulates function and phenotype. In addition, exosomes are an important component of paracrine signaling in stem-cell-based therapy and can be used as a stand-alone therapy or as a drug delivery system. The remarkable potential of exosomes has paved the pathway for cell-free treatment in bone regeneration. Exosomes are enriched in distinct noncoding RNAs (ncRNAs), including microRNAs, long ncRNAs and circular RNAs. Different ncRNAs have multiple functions. Altered expression of ncRNA in exosomes is associated with the regenerative potential and development of various diseases, such as femoral head osteonecrosis, myocardial infarction, and cancer. Although there is increasing evidence that exosome-derived ncRNAs (exo-ncRNAs) have the potential for bone regeneration, the detailed mechanisms are not fully understood. Here, we review the biogenesis of exo-ncRNA and the effects of ncRNAs on angiogenesis and osteoblast- and osteoclast-related pathways in different diseases. However, there are still many unsolved problems and challenges in the clinical application of ncRNA; for instance, production, storage, targeted delivery and therapeutic potency assessment. Advancements in exo-ncRNA methods and design will promote the development of therapeutics, revolutionizing the present landscape.

The Emerging Role of Non-Coding RNAs in Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells

Autologous bone marrow-derived mesenchymal stem cells (BMSCs) are more easily available and frequently used for bone regeneration in clinics. Osteogenic differentiation of BMSCs involves complex regulatory networks affecting bone formation phenomena. Non-coding RNAs (ncRNAs) refer to RNAs that do not encode proteins, mainly including microRNAs, long non-coding RNAs, circular RNAs, piwi-interacting RNAs, transfer RNA-derived small RNAs, etc. Recent in vitro and in vivo studies had revealed the regulatory role of ncRNAs in osteogenic differentiation of BMSCs. NcRNAs had both stimulatory and inhibitory effects on osteogenic differentiation of BMSCs. During the physiological condition, osteo-stimulatory ncRNAs are upregulated and osteo-inhibitory ncRNAs are downregulated. The opposite effects might occur during bone degenerative disease conditions. Intracellular ncRNAs and ncRNAs from neighboring cells delivered via exosomes participate in the regulatory process of osteogenic differentiation of BMSCs. In this review, we summarize the recent advances in the regulatory role of ncRNAs on osteogenic differentiation of BMSCs during physiological and pathological conditions. We also discuss the prospects of the application of modulation of ncRNAs function in BMSCs to promote bone tissue regeneration in clinics.

Noncoding RNA in Extracellular Vesicles Regulate Differentiation of Mesenchymal Stem Cells

To achieve the desired outcome in tissue engineering regeneration, mesenchymal stem cells need to undergo a series of biological processes, including differentiating into the ideal target cells. The extracellular vesicle (EV) in the microenvironment contributes toward determining the fate of the cells with epigenetic regulation, particularly from noncoding RNA (ncRNA), and exerts transportation and protective effects on ncRNAs. We focused on the components and functions of ncRNA (particularly microRNA) in the EVs. The EVs modified by the ncRNA favor tissue regeneration and pose a potential challenge.

Irradiated cell-derived exosomes transmit essential molecules inducing radiotherapy resistance

Radio-resistance has always been a major obstacle in radiation therapy (RT) progress. Radiotherapy (RT) leads to changes in the contents of released exosomes. The researches have shown that irradiated cell-derived exosomes influence recipient cell proliferation, migration, cell cycle arrest and apoptosis. All evidence indicates that exosomes play a significant role in radio-resistance. In this review, we describe the potential role of exosomes in cancer. We summarize that the irradiated cell-derived exosomes influence radio-resistance in recipient cells by three main mechanisms: 1) enhancing DNA repair, 2) regulating cell death signalling pathways, 3) inducing cancer cells to exhibit stem cell properties. We also discuss that the origin of the phenomenon might be the changes of molecular mechanisms of irradiated cell-derived exosomes formation affected by RT. Further, targeting exosomes as an adjuvant therapy might be a promising way for cancer treatments.

microRNA-265 Regulates Bone Marrow Mesenchymal Stem Cells Differentiation and Promotes Sepsis Lung Injury Repair via Transforming Growth Factor Beta 1

Our study investigates whether miR-265 regulates the differentiation of rat bone marrow mesenchymal stem cells (BMSCs) into alveolar type II epithelial cells (ATII) through TGF-β1 and promotes lung injury repair in rats with sepsis, thereby inhibiting sepsis progression. 25 patients with sepsis admitted to the Respiratory and Critical Care Medicine Department of the hospital and 17 normal controls were included. TGF-β1 level was measured by ELISA. miR-265 level was measured by qRT-PCR and AT II-related genes and proteins expression was analyzed by western blot and qRT-PCR. miR-265 expression was significantly higher in sepsis patients than normal group. Progenitor BMSCs were long and shuttle-shaped after 1 and 3 days of growth. Cultured MSCs had low expression of the negative antigen CD34 (4.32%) and high expression of the positive antigen CD44 (99.87%). TGF-β1 level was significantly increased with longer induction time, while miR-265 expression was significantly decreased in cell culture medium. miR-265 interference significantly decreased TGF-β1 expression. In conclusion, miR-265 inhibits BMSC differentiation to AT II via regulation of TGF-β1, thereby inhibiting sepsis progression.

Silencing of circCDC14A prevents cerebral ischemia-reperfusion injury via miR-23a-3p/CXCL12 axis

Ischemic stroke is one of the main causes of death and disability. Circular RNAs (circRNAs) have received extensive attention in the pathogenesis of ischemic stroke. Here, we evaluated the role of circCDC14A in cerebral ischemia-reperfusion (CI/R) injury in vivo and in vitro. The expression of circCDC14A was significantly upregulated in the middle cerebral artery occlusion (MCAO) model and oxygen and glucose deprivation/reoxygenation (OGD/R)-treated HT22 cells. Knockdown of circCDC14A suppressed the cell viability reduction caused by OGD/R, as well as cell damage and apoptosis. Mechanistically, circCDC14A acted as a sponge for miR-23a-3p and promoted the expression of chemokine stromal-derived factor-1 (CXCL12) by negatively regulating miR-23a-3p. Rescue experiments further confirmed that miR-23a-3p inhibitor or circCDC14A-overexpression vectors blocked the beneficial effects of circCDC14A knockdown in OGD/R-induced HT22 cells. Moreover, knockdown of circCDC14A suppressed MCAO-induced cerebral infarction and neurological damage, as well as the brain tissue damage and neuronal apoptosis in vivo. Consistently, miR-23a-3p antagomir treatment abolished the cerebral protective effects of circCDC14A knockdown on MCAO mice. In conclusion, circCDC14A promoted CI/R injury by regulating the miR-23a-3p/CXCL12 axis, which suggested that circCDC14A may become a potential therapeutic target for CI/R injury.

Focusing on OB-OC-MΦ Axis and miR-23a to Explore the Pathogenesis and Treatment Strategy of Osteoporosis

Osteoporosis is a bone metabolic disorder characterized by decreased bone density and deteriorated microstructure, which increases the risk of fractures. The imbalance between bone formation and bone resorption results in the occurrence and progression of osteoporosis. Osteoblast-mediated bone formation, osteoclast-mediated bone resorption and macrophage-regulated inflammatory response play a central role in the process of bone remodeling, which together maintain the balance of the osteoblast-osteoclast-macrophage (OB-OC-MΦ) axis under physiological conditions. Bone formation and bone resorption disorders caused by the imbalance of OB-OC-MΦ axis contribute to osteoporosis. Many microRNAs are involved in the regulation of OB-OC-MΦ axis homeostasis, with microRNA-23a (miR-23a) being particularly crucial. MiR-23a is highly expressed in the pathological process of osteoporosis, which eventually leads to the occurrence and further progression of osteoporosis by inhibiting osteogenesis, promoting bone resorption and inflammatory polarization of macrophages. This review focuses on the role and mechanism of miR-23a in regulating the OB-OC-MΦ axis to provide new clinical strategies for the prevention and treatment of osteoporosis.

Irradiation affects the structural, cellular and molecular components of jawbones

PURPOSE

Emerging evidence shows that changes in the bone and its microenvironment following radiotherapy are associated with either an inhibition or a state of low bone formation. Ionizing radiation is damaging to the jawbone as it increases the complication rate due to the development of hypovascular, hypocellular, and hypoxic tissue. This review summarizes and correlates the current knowledge on the effects of irradiation on the bone with an emphasis on jawbone, as these have been a less extensively studied area.

CONCLUSIONS

The stringent regulation of bone formation and bone resorption can be influenced by radiation, causing detrimental effects at structural, cellular, vascular, and molecular levels. It is also associated with a high risk of damage to surrounding healthy tissues and an increased risk of fracture. Technological advances and research on animal models as well as a few human bone tissue studies have provided novel insights into the ways in which bone can be affected by high, low and sublethal dose of radiation. The influence of radiation on bone metabolism, cellular properties, vascularity, collagen, and other factors like inflammation, reactive oxygen species are discussed.

Bone Marrow Mesenchymal Stem Cell (BMSC)-Derived Exosomes Increase Colon Cancer Cell Apoptosis and Inhibit Proliferation and Migration

This study aims to investigate whether bone marrow mesenchymal stem cell (BMSC) exosomes (BMSC-exos) affects the progression of colon cancer. Ultracentrifugation was used to extract and collect BMSC-exos which were assessed under electron microscope and by flow cytometry. The BMSCs were divided into two groups: control group treated with α-MEM basal medium and experimental group with exosomes (10 μg/ml). Exos were extracted from BMSCs and co-cultured with colon cancer cells, followed by analysis of cell viability by CCK-8 assay and GLUT3 mRNA and protein expression by RT-qPCR and Western blot. The electron microscope analysis indicated that the primary BMSCs showed a long spindle shape with a negative expression of antigen CD34 and positive antigen CD90. Importantly, exos inhibited the viability of colon cancer cells HCT116 and decreased the expression of GLUT3, suggesting that exos might increase the colon cancer cell apoptosis. In conclusion, BMSC-exos inhibit cell progression in colon cancer and might be served as a promising biomarker.

Periodontal and Dental Pulp Cell-Derived Small Extracellular Vesicles: A Review of the Current Status

Extracellular vesicles (EVs) are membrane-bound lipid particles that are secreted by all cell types and function as cell-to-cell communicators through their cargos of protein, nucleic acid, lipids, and metabolites, which are derived from their parent cells. There is limited information on the isolation and the emerging therapeutic role of periodontal and dental pulp cell-derived small EVs (sEVs, <200 nm, or exosome). In this review, we discuss the biogenesis of three EV subtypes (sEVs, microvesicles and apoptotic bodies) and the emerging role of sEVs from periodontal ligament (stem) cells, gingival fibroblasts (or gingival mesenchymal stem cells) and dental pulp cells, and their therapeutic potential in vitro and in vivo. A review of the relevant methodology found that precipitation-based kits and ultracentrifugation are the two most common methods to isolate periodontal (dental pulp) cell sEVs. Periodontal (and pulp) cell sEVs range in size, from 40 nm to 2 μm, due to a lack of standardized isolation protocols. Nevertheless, our review found that these EVs possess anti-inflammatory, osteo/odontogenic, angiogenic and immunomodulatory functions in vitro and in vivo, via reported EV cargos of EV–miRNAs, EV–circRNAs, EV–mRNAs and EV–lncRNAs. This review highlights the considerable therapeutic potential of periodontal and dental pulp cell-derived sEVs in various regenerative applications.