Skip to main content
Download PDF

Mesenchymal stem cell-derived extracellular vesicles for treatment of bone loss within periodontitis in pre-clinical animal models: a meta-analysis

BMC Oral Health volume 23, Article number: 701 (2023) Cite this article

Abstract

Background

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) represent an effective and promising strategy for periodontitis, although studies remain pre-clinical. Herein, a meta-analysis was conducted to assess the efficacy of MSC-EVs in animal models of periodontitis.

Methods

The PubMed, Web of Science, and Embase electronic databases were searched up to Dec 2022 to retrieve preclinical studies examining the use of MSC-EVs for periodontitis treatment. Meta-analyses and sub-group analyses were performed to assess the effect of MSC-EVs on Bone Volume/Total Volume (BV/TV) or the distance between the cementoenamel junction and alveolar bone crest (CEJ-ABC) in pre-clinical animal models of periodontitis.

Results

11 studies published from Mar 2019 to Oct 2022 met the inclusion criteria. Overall, MSC-EVs contributed to periodontal bone regeneration in the inflammatory bone loss area due to periodontitis, as represented by a weighted mean difference (WMD) of 14.07% (95% CI = 6.73, 21.41%, p < 0.001) for BV/TV and a WMD of -0.12 mm (95% CI= -0.14, -0.11 mm, p < 0.001) for CEJ-ABC. However, sub-analysis suggested that there was no significant difference in CEJ-ABC between studies with bioactive scaffolds and studies without bioactive scaffolds (p = 0.60).

Conclusions

The present study suggests that MSC-EVs may represent an attractive therapy for the treatment of inflammatory bone loss within periodontitis.

Peer Review reports

Introduction

Periodontitis is a widespread disease that affects almost half of the adult population worldwide, and is characterized by connective tissue attachment loss and alveolar bone destruction, with subsequent tooth loss [1, 2]. In addition, toxins and pathogenic factors produced by periodontal pathogens are vital risk factors for a variety of systemic diseases, such as Alzheimer’s disease, diabetes, cardiovascular disease, cancer and autoimmune diseases, which seriously affect the quality of human life [3,4,5]. Therefore, the prevention and treatment of periodontitis is an intractable problem that needs to be solved. Over the past few decades, the strategy of stem cell-based periodontal regeneration has shed new light on facilitating new tissue in periodontal pockets [6, 7]. However, the clinical translation of mesenchymal stem cells (MSCs), such as periodontal ligament stem cells (PDLSCs), in patients suffering from periodontitis has been disappointing up to now [8, 9]. Analyses of the causes of stem cell transplantation failure in the clinic have shown that stem cell transplantation involves complicated operation measures and clinical transformation issues, including clinical preparation, cell storage and transportation, survival and viability of stem cells, and potential immune rejection after allogeneic cell implantation [10, 11]. Moreover, because the intrabony periodontal defect is an inflammatory microenvironment, the transplanted stem cells may be functionally compromised, along with other not fully clarified reasons and risks, such as aberrant differentiation and reduced stemness, thus dampening the enthusiasm of researchers to try to use stem cell transplantation directly [9, 12, 13].

Based on the current understanding, transplanted stem cells contribute to tissue regeneration and repair mainly via their paracrine functions. These paracrine secretions include a variety of growth factors, chemokines, cytokines and extracellular vesicles (EVs). These agents have been well demonstrated to regulate tissue regeneration by mobilizing or regulating the bioactivity of resident cells and modulating the microenvironment of the implantation area. EVs, particularly, have been regarded as the principal element contributing to the therapeutic efficacy of parent cells [14]. EVs are cell-secreted nanovesicles with the size ranging from 30 to more than 1000 nm, and among them, typical small EVs with the size of 30–150 nm are referred to as “exosomes” [15]. In fact, EVs contribute to intercellular communication by delivering specific agents to target cells or tissues for their loaded cargos, including various bioactive molecules in terms of mRNAs, lipids, proteins, DNA, circRNAs and microRNAs [16]. Current studies have confirmed that EVs participate in various biological and pathological processes, such as antigen presentation, coagulation process, virus transmission, tumor growth, and tissue regeneration [17]. More importantly, growing evidence has demonstrated that EVs may represent a promising therapeutic approach due to their advantages over donor cells, in terms of low propensity to initiate immune rejection after allogeneic administration, no risk of aneuploidy and high stability. In addition, it was reported that EVs can be stored for a long time and remain stable because their special membranous structure can prevent EVs from being degraded by enzymes [18,19,20]. Under this context, increasing numbers of studies have demonstrated that EVs secreted by stem cells may represent a promising and attractive approach for the treatment of periodontitis [13, 21].

Although accumulating evidence indicates that MSC-EVs may be a viable ready-to-use and cell-free therapeutic strategy for the treatment of periodontal defects [8, 12, 13], relevant clinical studies are lacking to date, and pre-clinical animal models remain the main source of study evidence, which has contributed prominently to the current understanding of periodontitis. Additionally, these pre-clinical models have been the spearhead to explore new therapeutic strategies for periodontitis. Thus, the principal objective of the present meta-analysis was to assess the efficacy of MSC-EVs in treating inflammatory bone loss in preclinical periodontitis models, with the aim of providing the most recent available evidence for MSC-EVs in periodontitis and promoting the translation of this novel cell-free therapy towards clinical trials for the treatment of periodontitis.

Methods

Protocol and registration

The present study was registered in the International Prospective Register of Systematic Reviews (PROSPERO, https://www.crd.york.ac.uk/prospero/, CRD42023385352), and the systematic review and meta-analysis were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines.

Search strategy

Online databases in terms of PubMed, EMBASE and the Web of Science were searched for research articles published in English that examined the use of MSC-EVs to treat periodontitis. The search terms including the following: (“extracellular vesicle” or “exosome” or “EV” or “micro vesicle” or “microparticle” or “micro-vesicle” or “small extracellular vesicle” or “microvesicle” or “MV”) and (“stem cell” or “mesenchymal stem Cell” or “MSC”) and (“periodontitis” or “periodontal disease” or “periodontal defect” or “periodontal regeneration” or “periodontal bone loss” or “alveolar bone defect”). The search strategies were modified according to database and used filters for preclinical animal models. In addition, the reference lists of the included studies were manually searched to identify potentially relevant studies. For the present study, we followed the PICOS structure, population (P): animal models of periodontitis, with no restrictions on species or modeling approaches; Intervention (I): EVs derived from MSCs; Comparison (C): pre-clinical models of periodontitis treated without MSC-EVs; Outcome (O): Bone Volume/Total Volume (BV/TV), the distance between the cementoenamel junction and alveolar bone crest (CEJ-ABC) and signaling pathways involved; Study design (S): randomized, non-randomized or quasi-randomized in vivo studies.

Eligibility criteria

The inclusion criteria were as follows: (1) studies on pre-clinical models of periodontitis; (2) studies on EVs derived from MSCs; (3) randomized, non-randomized or quasi-randomized in vivo studies; (4) studies comparing the effects of MSC-EVs with controls in pre-clinical models of periodontitis; and (5) studies published in English and full-text available.

The exclusion criteria were as follows: (1) studies on EVs derived from other cells instead of MSCs or other tissues in periodontitis; (2) studies without in vivo models and results; (3) studies exploring the function of MSCs or their conditioned medium in periodontitis; (4) studies with insufficient information or data that could not be fully extracted; and (5) non-comparative studies, case reports, review articles, commentaries, conference proceedings, letters to the editor, abstract editorials, monographs, and other study types.

Literature search and study selection

A systematic literature search of all potential studies was performed to identify all the relevant studies (published up to Dec, 2022). In specific, two reviewers (HZ, YXQ) independently searched the databases and then excluded the duplicates. Then, three investigators (YXQ, DDP, AL) screened and evaluated the research titles and abstracts based on the eligibility criteria. The remaining studies that appeared to meet the aforementioned inclusion criteria were then subjected to full-text screening. Any disagreements regarding inclusion were resolved through discussion with all reviewers until a consensus was achieved.

Data extraction

Two authors (HZ, YXQ) extracted the relevant data from the included studies independently using a specific form (Excel, Microsoft, Seattle, USA), and then, all the authors re-checked and confirmed the obtained raw data. The following data were extracted from each study: (1) MSC source, MSC-EV isolation method and characterization, and the administration dose of MSC-EVs; (2) study design, i.e., the comparator information, animal species, sample size, and administration route; (3) intervention characteristics, i.e., delivery strategies in terms of hydrogels and/or scaffolds and others, modification to MSC-EVs; (4) outcomes i.e., BV/TV, CEJ-ABC, and signaling pathways involved; and (5) study characteristics, i.e., authors, location of the research, and publication year. Data were acquired from the presented graphs with the help of OriginPro2021(Version: 9.8.0.200) when the raw data were not provided.

Outcome measures

To assess the function of MSC-EVs in the treatment of bone loss within periodontitis, the primary outcome measure was to compare the BV/TV, CEJ-ABC changes in treating inflammatory bone loss in periodontitis models with the control groups. The secondary outcome measure was the signaling pathways involved in the MSC-EVs for treatment of bone loss within periodontitis.

Quality assessment

Risk of bias assessment for studies was carried out according to the guidelines of the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) bias risk tool [22]; specifically, for each study, the selection bias, performance bias, detection bias, attrition bias, reporting bias and other sources of bias were assessed by two reviewers (YXQ, CHZ) independently. For each domain, the risk of bias was categorized as high, low or unclear (if the risk of bias could not be assessed due to a lack of sufficient information). Any disagreement regarding the risk of bias was resolved through discussion with a third reviewer (DDP).

Data analysis

For the present meta-analysis, the combined effect size was expressed as the weight mean difference (WMD) with a 95% confidence interval (CI). p < 0.05 (two-tailed) was considered to be statistically significant. The I2 statistic was performed to quantify the heterogeneity across studies; specifically, I2 values indicating low, moderate and high heterogeneity with the thresholds of 25%, 50% and 75%, respectively [23]. In addition, sensitivity and sub-analyses were conducted to explore the sources of heterogeneity and to identify other potentially confounding factors. Publication bias was assessed with a funnel plot; besides, as a quantitative complement for the funnel plot, Egger’s test was also performed to evaluate the P value. Stata 15.1 (StataCorp, College Station, TX, USA) and RevMan 5.4.1 software (Cochrane Collaboration; www.cochrane.org/) were utilized for data analyses.

Results

Literature search & study characteristics

The study selection process is illustrated in Fig. 1. Specifically, 223 articles were initially identified based on the search strategy. After the initial review based on title/ abstract reading (Supplement file Table S1), 29 articles remained for further assessment. Then, 18 articles were excluded based on the inclusion and exclusion criteria, specifically, in vitro results only (n = 4), incomplete data (n = 5), EVs secreted from other cells instead of MSCs (n = 4), review articles (n = 3), and preprint articles that have not been peer reviewed (n = 2). Ultimately, the present meta-analysis included 11 full-text articles published from 2019 to 2022.

Fig. 1
figure 1

Flowchart of the enrolled studies on mesenchymal stem cell-derived extracellular vesicle (MSC-EV) therapy in periodontitis animal models

Full size image

The main characteristics within the included studies are illustrated in Table 1. A total of 103 rodents (rats and mice) were included in the meta-analysis of MSC-EVs for periodontitis. With regard to the specific animals employed, six studies used Sprague–Dawley rats [8, 12, 13, 34, 38, 41], and five studies used mice (four studies with C57BL/6 [25, 39, 40, 42] and one study with CD-1 mice [43]). In terms of the periodontitis models, four studies utilized alveolar bone defect models that were created in the alveolar bone of first or second molars, with the outcomes related to changes in BV/TV [8, 12, 13, 34]; seven studies used the silk thread ligation method with or without coated bacteria, with the results related to the change in CEJ-ABC [25, 38,39,40,41,42,43]. With respect to the stem cell type (for EV isolation), three studies used human bone marrow mesenchymal stem cells (hMSCs) [12, 40, 41], two studies used stem cells from human exfoliated deciduous teeth (SHEDs) [34, 43], two studies used periodontal ligament stem cells (PDLSCs) [8, 13], two studies used dental pulp stem cells (DPSCs) [25, 42], one study used dental follicle cells (DFCs) [38], and one study used human gingiva tissue-derived MSCs (hGMSCs) [39].

Table 1 Characteristics of the included studies
Full size table

Isolation and characterization of MSC-EVs

For the extraction method and characteristics of MSC-EVs, six studies utilized ultracentrifugation [13, 25, 34, 40, 42, 43], one study used exosome isolation reagent [38, 41], one study used Tangential flow filtration [12], and two studies used both ultracentrifugation and exosome isolation reagent [8, 39]. The size and quantity of EVs were assessed with the help of nanoparticle tracking analysis (NTA), dynamic light scattering analysis and NanoSight Analyzer, and the obtained EV diameter mostly ranged from 30 to 200 nm. In addition, the morphology of MSC-EVs was observed using transmission electron microscopy. Besides, EV surface markers in terms of CD9, CD63, CD81, ALIX, and TSG-101 were examined using western blotting or flow cytometry.

Administration of MSC-EVs

For the administration methods, four studies utilized hydrogel as the EV carrier [13, 38, 41, 42], two studies used β-TCP [8, 24], one study used collagen sponge for EV delivery [12], and four studies did not use any bioactive materials [25, 39, 40, 43]. MSC-EVs with or without bioactive agents were placed into the alveolar bone defect or injected into the periodontal pocket directly. In addition, it was noteworthy that there were large differences in the total doses of MSC-EVs, varying from 20 to 100 µg or much more.

Risk of bias

Quality assessments for all enrolled articles were performed. The details of the risk of bias are illustrated in Fig. 2. In specific, no study fulfilled all the criteria, while all studies exhibited similar baseline characteristics for the experimental and control groups. In particular, almost all of these studies were categorized as “unclear” for quality assessment of “allocation concealment” and “blinding for performance and detection” due to the absence of detailed information. Only one study was rated as “high” risk for their not random housing. In addition, no additional sources of bias were identified.

Fig. 2
figure 2

Risk of bias assessment. A Graph of the risk of bias for the included studies, B Graph of the risk of bias summary for the included studies

Full size image

Function of MSC-EVs on treatment of bone loss within periodontitis

Based on the results of the present meta-analysis, MSC-EV treatment demonstrated a favorable effect to attenuate bone loss due to periodontitis, with a significant increase in WMD of BV/TV (14.07%; 95% CI = 6.73, 21.41%, p < 0.001, Fig. 3) and significant decrease of CEJ-ABC (-0.12 mm; 95% CI = -0.14, -0.11 mm, p < 0.001, Fig. 4) compared with the control groups, and a lower heterogeneity for CEJ-ABC outcomes (I2 = 36%). However, there was significant heterogeneity for BV/TV outcomes (I2 = 99%), which limits the strength of the conclusions regarding the function of MSC-EVs on treating bone defects within periodontitis.

Fig. 3
figure 3

Forest plot demonstrated the mean effect size and 95% confidence interval (CI) for bone volume/total volume (BV/TV)

Full size image
Fig. 4
figure 4

Forest plot shows the mean effect size and 95% confidence interval (CI) for distance between the cementoenamel junction and the alveolar bone crest (CEJ-ABC)

Full size image

In addition, subgroup analysis for CEJ-ABC outcomes based on the EV delivery methods (in terms of with or without collagen sponge, β-tricalcium phosphate (β-TCP), hydrogel) was performed, and according to the results (Fig. 5), the decrease in WMD of CEJ-ABC between studies that with or without bioactive agents was not significant (p = 0.60).

Fig. 5
figure 5

Subgroup analysis assessing the change in the distance between the cementoenamel junction and the alveolar bone crest (CEJ-ABC) in MSC-EV administration with or without bioactive scaffolds. MSC-EV, mesenchymal stem cell-derived extracellular vesicle

Full size image

Signaling pathways impacted by MSC-EVs

The included studies reported that several pathways, including RANKL-RANK [38, 39, 41], Wnt [8], AMPK [34], AKT and ERK [12], NF-κB p65 and p38 MAPK [42], Smad5/Runx2 [43], and the miR-1246/Nfat5 axis [40] (Table 1; Fig. 6), may be involved in the alveolar bone regeneration process mediated by MSC-EVs.

Fig. 6
figure 6

Mechanisms of MSC-EV treatment on periodontitis in included studies. Studies reported that signaling pathways including RANKL-RANK, Wnt, AMPK, AKT and ERK, NF-κB p65 and p38 MAPK, Smad5/Runx2, and the miR-1246/Nfat5 axis, were involved in the bone regeneration process mediated by MSC-EVs. MSC-EV, mesenchymal stem cell-derived extracellular vesicle. MSC-EV, mesenchymal stem cell-derived extracellular vesicle

Full size image

Sensitivity analysis

Sensitivity analysis was also performed to assess the stability of the present meta-analysis results. Figure 7 showed that the circles corresponding to the 11 included studies were located near the middle vertical line where the combined effect size located. It appeared that there were no studies had a significant impact on the combined effect size. Therefore, for the pooled MD, neither BV/TV outcome nor CEJ-ABC outcome were significantly affected by any study.

Fig. 7
figure 7

Sensitivity analysis of the studies included in bone volume/total volume (BV/TV) (A) and distance between the cementoenamel junction and the alveolar bone crest (CEJ-ABC) (B)

Full size image

Publication bias

Funnel plots and Egger’s tests were carried out to assess publication bias. As shown in Fig. 8; Table 2, the approximately symmetrical distributions of funnel plots and Egger’s test indicated that there was no significant publication bias for CEJ-ABC (p = 0.43). Funnel plot assessment was not carried out for BV/TV due to the limited number of studies (n = 4), while Egger’s test suggested an absence of publication bias for BV/TV (p = 0.55).

Fig. 8
figure 8

Publication-bias analysis results. Funnel plots for distance between the cementoenamel junction and the alveolar bone crest (CEJ-ABC)

Full size image
Table 2 Egger’s test of bone volume and total volume (BV/TV) and the distance between the cementoenamel junction and the alveolar bone crest (CEJ-ABC)
Full size table

Discussion

There has been no effective strategy to cure inflammatory bone loss within periodontitis thus far. As key paracrine elements of MSCs, EVs were verified to possess the features of parent cells, and were considered to be an alternative for stem cell therapy due to their therapeutic potential in tissue regeneration [24, 25]. Under this context, increasing numbers of studies have been performed to explore the function of MSC-EVs in periodontitis animal models. The present meta-analysis of 11 studies afforded a relatively comprehensive summary of the efficacy of MSC-EVs in pre-clinical rodent model of periodontitis. Pooled analyses demonstrated that MSC-EVs could significantly promote alveolar bone regeneration within the inflammatory bone loss area, indicating that therapies based on MSC-EVs may yield new avenues for periodontitis in the clinic. However, considering the limited number of studies, more studies are needed to carry out to identify the beneficial effects of MSC-EVs in experimental periodontitis.

In our meta-analysis, BV/TV and CEJ-ABC outcomes were collected and analyzed to evaluate the efficacy of MSC-EVs in periodontitis. BV/TV and CEJ-ABC are the most commonly used indicators to evaluate the resorption and reconstruction performance of alveolar bone, especially for periodontitis animal models. BV/TV outcomes were demonstrated to accurately reflect cancellous and trabecular bone connectivity and bone volume, which are key indicators of bone quality [26]. While CEJ-ABC was defined as the distance between the cementoenamel junction and alveolar bone crest, which was also measured by micro-computed tomography, it truly reflects newly-formed bone in the inflammatory bone loss area due to periodontitis, thus carrying more clinical significance and reference value. Based on the meta-analysis results, much more new bone formed (BV/TV results) and the bone crest level was markedly elevated (CEJ-ABC results) in the MSC-EV groups compared to the control groups.

EV administrations with bioactive materials in terms of collagen sponge, β-TCP, and hydrogel were also investigated by several studies, and based on the enrolled studies, administration of EVs along with these bioactive materials exhibited significant pro-osteogenic potential in several studies although, pooled estimates of benefit from studies that MSC-EVs with bioactive agents were similar compared to studies of MSC-EVs without. Considering that the enhancement of EV retention has always been a challenging issue within the inflammatory bone defect environment, researchers have introduced bioactive materials into the EV research field. These materials were verified to provide mechanical support to the bone defect site, and facilitate the delivery and retention of EVs [27, 28]. In addition, bioactive scaffolds could permit the controlled release of EVs and further lead to more robust bone formation performance [29,30,31]. Matrigel is one of the most commonly used carriers for EVs, because its specific porose structure facilitates the prevision and delivery of EVs. In addition, it was reported that the controlled release of EVs can be achieved by regulating Matrigel degradation [32, 33]. A variety of studies have utilized TCP as the carrier for EVs to promote bone regeneration and repair, especially for bone defects resulted by inflammatory periodontitis. Based on these studies, EV-loaded TCP delivered a significantly beneficial function on alveolar bone regeneration within periodontitis [34, 35]. However, at present, controlling the loading capacity and the release speed of EVs remains intractable and requires further exploration [8]. Additionally, collagen sponges are considered to be a beneficial scaffold for EV administration in periodontitis and are widely utilized to maintain space along with other biologics for periodontal tissue regeneration [36, 37]. Although an obvious benefit from the use of biomaterial scaffolds was not identified in the present meta-analysis, their enhancing biological characteristics suggest that future study of these bioactive agents as EV carriers may be beneficial and worthwhile.

Within the studies identified in the present meta-analysis, some researchers have pre-treated MSCs before EV isolation, for instance, treating MSCs with LPS [38] or TNF-α [39], or culturing MSCs in a 3D system [40] before EV administration. Based on the reported outcomes, all of these preconditioning techniques resulted in significantly elevated bone crest levels, while due to the limited study number, a pooled sub-analysis was not performed. Additionally, investigators reported that MSC-EV administration in periodontitis led to changes in putative signaling pathways involved in osteogenesis. Three studies reported that MSC-EVs promote bone regeneration by RANKL-RANK signaling [38, 39, 41] and other pathways including Wnt signalling [8], AMPK signaling [34], AKT and ERK signaling [12], NF-κB p65 and p38 MAPK signaling [42], Smad5/Runx2 signaling [43], and the miR-1246/Nfat5 axis [40], were also reported to be involved in the bone regeneration process mediated by MSC-EVs. These pathways were previously demonstrated to be implicated in the bone injury healing process [26, 44]. Based on this context, modifying MSC-EVs with specific biologic signaling molecules (proteins, mRNA, miRNAs, lipids), and then deliver these biomolecules to target cells via modulating these above pathways is a topic worthy of further study.

Risk of bias of the enrolled studies was evaluated using the SYRCLE tool [22]. almost all of the studies were rated to be at an unclear risk in domains of selection (allocation concealment), performance (blinding), and detection (random outcome assessment, blinding), and one study was found to be at a high risk in performance (not random housing). Other significant bias including selection (baseline characteristics), attrition (incomplete outcome data), reporting (selective reporting) was not appreciated in our present studies. Future research should pay more attention to study designs to reduce the aforementioned potential risk of bias, which will increase our confidence in study results and contribute to performing a meaningful meta-analysis.

It is well known that meta-analyses of animal studies could offer guidance for basic research and clinical endeavors. To the best of our knowledge, this is the first meta-analysis of MSC-EVs in pre-clinical periodontitis experiments, which provide, to a certain degree, a summary of the efficacy of MSC-EV administration in periodontitis. However, several potential limitations should be considered. First, a relatively small number of studies within this meta-analysis, and the inevitable or accompanying presence of uncontrollable biases or uncertainties, may introduce potential influence and other bias, the explorations of the heterogeneity were not feasible for the BV/TV outcomes for the small number (n = 4) of included studies. Second, the 11 included studies were all rodent animal models; thus, more large-animal studies, such as pigs, should be considered in future research. Third, several factors in terms of EV source (stem cell types), EV isolation and storage methods (including freezing), EV administration dosages, timing and frequency may affect the efficacy of EVs in periodontitis, considering these above factors, the results of this study should be interpreted with caution.

For the future research, well designed large-scale animal studies should be performed, and large-animal periodontitis models should be established to confirm the function of MSC-EVs in treating periodontitis. Besides, the safety issues of MSC-EVs, especially the adverse events, should be recorded. To promote the translation of MSC-EVs into clinical practice, much progress has been made for the improvement of targeting functions of EVs by unique engineered strategies, for instance, loading or modifying EVs with RNAs, peptides or proteins via utilization of genetically engineered donor MSCs [45, 46]. For EVs bear enormous application potential as biological drug delivery vehicles, and with the development of tissue engineering, the clinical application of EVs will eventually be realized.

Conclusion

Within the limitations of the present meta-analysis, MSC-EV administration delivered an effective function in the pre-clinical periodontitis animal models compared with the controls. While, the efficacy of MSC-EVs in periodontitis still needs to be further verified by large-scale animal studies as well as large-animal studies pre-clinically, with the aim of providing basis and clues for future clinical trials. Although, based on the present studies, the beneficial effect of scaffolds in treating bone loss was not confirmed, their specific biological properties suggest that these bioactive agents as EV vehicles may be of avail to treat periodontitis in future research.

Data Availability

All data generated or analyzed during this study are included in this published article.

Abbreviations

MSC:

mesenchymal stem cell

EV:

extracellular vesicle

CI:

confidence interval

WMD:

weighted mean difference

hMSC:

human mesenchymal stem cell

SHED:

stem cells from human exfoliated deciduous teeth

PDLSC:

periodontal ligament stem cell

DPSC:

dental pulp stem cell

HHH-DP:

human leukocyte antigen haplotype homo dental pulp cell

DFC:

dental follicle cell

hGMSC:

human gingival tissue-derived mesenchymal stem cell

References

  1. Li H, Deng Y, Tan M, Feng G, Kuang Y, Li J, Song J. Low-intensity pulsed ultrasound upregulates osteogenesis under inflammatory conditions in periodontal ligament stem cells through unfolded protein response. Stem Cell Res Ther. 2020;11(1):215.

    PubMed  PubMed Central  Google Scholar 

  2. Yan W, Cao Y, Yang H, Han N, Zhu X, Fan Z, Du J, Zhang F. CB1 enhanced the osteo/dentinogenic differentiation ability of periodontal ligament stem cells via p38 MAPK and JNK in an inflammatory environment. Cell Prolif. 2019;52(6):e12691.

    PubMed  PubMed Central  Google Scholar 

  3. Peres MA, Macpherson LMD, Weyant RJ, Daly B, Venturelli R, Mathur MR, Listl S, Celeste RK, Guarnizo-Herreño CC, Kearns C, Benzian H, Allison P, Watt RG. Oral diseases: a global public health challenge. Lancet. 2019;394(10194):249–60.

    PubMed  Google Scholar 

  4. Dominy SS, Lynch C, Ermini F, Benedyk M, Marczyk A, Konradi A, Nguyen M, Haditsch U, Raha D, Griffin C, Holsinger LJ, Arastu-Kapur S, Kaba S, Lee A, Ryder MI, Potempa B, Mydel P, Hellvard A, Adamowicz K, Hasturk H, Walker GD, Reynolds EC, Faull RLM, Curtis MA, Dragunow M, Potempa J. Porphyromonas gingivalis in Alzheimer’s disease brains: evidence for disease causation and treatment with small-molecule inhibitors. Sci Adv. 2019;5(1):eaau3333.

    PubMed  PubMed Central  Google Scholar 

  5. Kinane DF, Stathopoulou PG, Papapanou PN. Periodontal diseases. Nat Rev Dis Primers. 2017;3:17038.

    PubMed  Google Scholar 

  6. Li G, Han N, Yang H, Zhang X, Cao Y, Cao Y, Shi R, Wang S, Fan Z. SFRP2 promotes stem cells from apical papilla-mediated periodontal tissue regeneration in miniature pig. J Oral Rehabil. 2020;47(Suppl 1):12–8.

    PubMed  Google Scholar 

  7. Han N, Zhang F, Li G, Zhang X, Lin X, Yang H, Wang L, Cao Y, Du J, Fan Z. Local application of IGFBP5 protein enhanced periodontal tissue regeneration via increasing the migration, cell proliferation and osteo/dentinogenic differentiation of mesenchymal stem cells in an inflammatory niche. Stem Cell Res Ther. 2017;8(1):210.

    PubMed  PubMed Central  Google Scholar 

  8. Lei F, Li M, Lin T, Zhou H, Wang F, Su X. Treatment of inflammatory bone loss in periodontitis by stem cell-derived exosomes. Acta Biomater. 2022;141:333–43.

    PubMed  Google Scholar 

  9. Zhao Y, Shi Y, Yang H, Liu M, Shen L, Zhang S, Liu Y, Zhu J, Lan J, Li J, Ge S. Stem cell microencapsulation maintains stemness in inflammatory microenvironment. Int J Oral Sci. 2022;14(1):48.

    PubMed  PubMed Central  Google Scholar 

  10. Phinney DG, Pittenger MF. Concise Review: MSC-Derived Exosomes for cell-free therapy. Stem Cells. 2017;35(4):851–8.

    PubMed  Google Scholar 

  11. Li W, Liu Y, Zhang P, Tang Y, Zhou M, Jiang W, Zhang X, Wu G, Zhou Y. Tissue-Engineered Bone immobilized with human adipose stem cells-derived Exosomes promotes bone regeneration. ACS Appl Mater Interfaces. 2018;10(6):5240–54.

    PubMed  Google Scholar 

  12. Chew JRJ, Chuah SJ, Teo KYW, Zhang S, Lai RC, Fu JH, Lim LP, Lim SK, Toh WS. Mesenchymal stem cell exosomes enhance periodontal ligament cell functions and promote periodontal regeneration. Acta Biomater. 2019;89:252–64.

    PubMed  Google Scholar 

  13. Zhao Y, Gong Y, Liu X, He J, Zheng B, Liu Y. The experimental study of Periodontal ligament stem cells derived Exosomes with Hydrogel accelerating bone regeneration on alveolar bone defect. Pharmaceutics. 2022;14(10):2189.

    PubMed  PubMed Central  Google Scholar 

  14. Murphy DE, de Jong OG, Brouwer M, Wood MJ, Lavieu G, Schiffelers RM, Vader P. Extracellular vesicle-based therapeutics: natural versus engineered targeting and trafficking. Exp Mol Med. 2019;51(3):1–12.

    PubMed  Google Scholar 

  15. Kalluri R, LeBleu VS. The biology, function, and biomedical applications of exosomes. Science. 2020;367(6478):eaau6977.

    PubMed  PubMed Central  Google Scholar 

  16. Su L, Li R, Zhang Z, Liu J, Du J, Wei H. Identification of altered exosomal microRNAs and mRNAs in Alzheimer’s disease. Ageing Res Rev. 2022;73:101497.

    PubMed  Google Scholar 

  17. Konala VB, Mamidi MK, Bhonde R, Das AK, Pochampally R, Pal R. The current landscape of the mesenchymal stromal cell secretome: a new paradigm for cell-free regeneration. Cytotherapy. 2016;18(1):13–24.

    PubMed  Google Scholar 

  18. Zhang ZG, Buller B, Chopp M. Exosomes - beyond stem cells for restorative therapy in stroke and neurological injury. Nat Rev Neurol. 2019;15(4):193–203.

    PubMed  Google Scholar 

  19. Terstappen GC, Meyer AH, Bell RD, Zhang W. Strategies for delivering therapeutics across the blood-brain barrier. Nat Rev Drug Discov. 2021;20(5):362–83.

    PubMed  Google Scholar 

  20. Jeyaram A, Jay SM. Preservation and Storage Stability of Extracellular vesicles for therapeutic applications. AAPS J. 2017;20(1):1.

    PubMed  Google Scholar 

  21. Wang M, Li J, Ye Y, Chen D, Song J. SHED-derived exosomes improve the repair capacity and osteogenesis potential of hPDLCs. Oral Dis. 2022 Feb 13.

  22. Hooijmans CR, Rovers MM, de Vries RB, Leenaars M, Ritskes-Hoitinga M, Langendam MW. SYRCLE’s risk of bias tool for animal studies. BMC Med Res Methodol. 2014;14:43.

    PubMed  PubMed Central  Google Scholar 

  23. Cui J, Jin L, Ding M, He J, Yang L, Cui S, Wang X, Ma J, Liu A. Efficacy and safety of mesenchymal stem cells in the treatment of systemic sclerosis: a systematic review and meta-analysis. Stem Cell Res Ther. 2022;13(1):118.

    PubMed  PubMed Central  Google Scholar 

  24. Petrosyan A, Martins PN, Solez K, Uygun BE, Gorantla VS, Orlando G. Regenerative medicine applications: an overview of clinical trials. Front Bioeng Biotechnol. 2022;10:942750.

    PubMed  PubMed Central  Google Scholar 

  25. Shimizu Y, Takeda-Kawaguchi T, Kuroda I, Hotta Y, Kawasaki H, Hariyama T, Shibata T, Akao Y, Kunisada T, Tatsumi J, Tezuka KI. Exosomes from dental pulp cells attenuate bone loss in mouse experimental periodontitis. J Periodontal Res. 2022;57(1):162–72.

    PubMed  Google Scholar 

  26. Kirkham AM, Bailey AJM, Tieu A, Maganti HB, Montroy J, Shorr R, Campbell TM, Fergusson DA, Lalu MM, Elmoazzen H, Allan DS. MSC-Derived Extracellular Vesicles in Preclinical Animal Models of Bone Injury: a systematic review and Meta-analysis. Stem Cell Rev Rep. 2022;18(3):1054–66.

    PubMed  Google Scholar 

  27. Wang J, Zhu M, Hu Y, Chen R, Hao Z, Wang Y, Li J. Exosome-hydrogel system in bone tissue Engineering: a promising therapeutic strategy. Macromol Biosci 2022 Dec 27:e2200496.

  28. Wang D, Cao H, Hua W, Gao L, Yuan Y, Zhou X, Zeng Z. Mesenchymal stem cell-derived extracellular vesicles for bone defect repair. Membr (Basel). 2022;12(7):716.

    Google Scholar 

  29. Yan HC, Yu TT, Li J, Qiao YQ, Wang LC, Zhang T, Li Q, Zhou YH, Liu DW. The delivery of Extracellular vesicles loaded in Biomaterial Scaffolds for Bone Regeneration. Front Bioeng Biotechnol. 2020;8:1015.

    PubMed  PubMed Central  Google Scholar 

  30. Pinheiro A, Silva AM, Teixeira JH, Gonçalves RM, Almeida MI, Barbosa MA, Santos SG. Extracellular vesicles: intelligent delivery strategies for therapeutic applications. J Control Release. 2018;289:56–69.

    PubMed  Google Scholar 

  31. Lu Y, Yang Y, Liu S, Ge S. Biomaterials constructed for MSC-derived extracellular vesicle loading and delivery-a promising method for tissue regeneration. Front Cell Dev Biol. 2022;10:898394.

    PubMed  PubMed Central  Google Scholar 

  32. Yu M, Gu G, Cong M, Du M, Wang W, Shen M, Zhang Q, Shi H, Gu X, Ding F. Repair of peripheral nerve defects by nerve grafts incorporated with extracellular vesicles from skin-derived precursor Schwann cells. Acta Biomater. 2021;134:190–203.

    PubMed  Google Scholar 

  33. Gangadaran P, Rajendran RL, Lee HW, Kalimuthu S, Hong CM, Jeong SY, Lee SW, Lee J, Ahn BC. Extracellular vesicles from mesenchymal stem cells activates VEGF receptors and accelerates recovery of hindlimb ischemia. J Control Release. 2017;264:112–26.

    PubMed  Google Scholar 

  34. Wu J, Chen L, Wang R, Song Z, Shen Z, Zhao Y, Huang S, Lin Z. Exosomes secreted by stem cells from human exfoliated deciduous Teeth promote alveolar bone defect repair through the regulation of Angiogenesis and Osteogenesis. ACS Biomater Sci Eng. 2019;5(7):3561–71.

    PubMed  Google Scholar 

  35. Ying C, Wang R, Wang Z, Tao J, Yin W, Zhang J, Yi C, Qi X, Han D. BMSC-Exosomes carry mutant HIF-1α for improving angiogenesis and osteogenesis in critical-sized calvarial defects. Front Bioeng Biotechnol. 2020;8:565561.

    PubMed  PubMed Central  Google Scholar 

  36. Del Suárez-López F, Monje A. Efficacy of biologics for alveolar ridge preservation/reconstruction and implant site development: an American Academy of Periodontology best evidence systematic review. J Periodontol. 2022;93(12):1827–47.

    Google Scholar 

  37. Ma L, Rao N, Jiang H, Dai Y, Yang S, Yang H, Hu J. Small extracellular vesicles from dental follicle stem cells provide biochemical cues for periodontal tissue regeneration. Stem Cell Res Ther. 2022;13(1):92.

    PubMed  PubMed Central  Google Scholar 

  38. Shi W, Guo S, Liu L, Liu Q, Huo F, Ding Y, Tian W. Small extracellular vesicles from Lipopolysaccharide-Preconditioned Dental follicle cells promote Periodontal Regeneration in an inflammatory microenvironment. ACS Biomater Sci Eng. 2020;6(10):5797–810.

    PubMed  Google Scholar 

  39. Nakao Y, Fukuda T, Zhang Q, Sanui T, Shinjo T, Kou X, Chen C, Liu D, Watanabe Y, Hayashi C, Yamato H, Yotsumoto K, Tanaka U, Taketomi T, Uchiumi T, Le AD, Shi S, Nishimura F. Exosomes from TNF-α-treated human gingiva-derived MSCs enhance M2 macrophage polarization and inhibit periodontal bone loss. Acta Biomater. 2021;122:306–24.

    PubMed  Google Scholar 

  40. Zhang Y, Chen J, Fu H, Kuang S, He F, Zhang M, Shen Z, Qin W, Lin Z, Huang S. Exosomes derived from 3D-cultured MSCs improve therapeutic effects in periodontitis and experimental colitis and restore the Th17 cell/Treg balance in inflamed periodontium. Int J Oral Sci. 2021;13(1):43.

    PubMed  PubMed Central  Google Scholar 

  41. Liu L, Guo S, Shi W, Liu Q, Huo F, Wu Y, Tian W. Bone marrow mesenchymal stem cell-derived small extracellular vesicles promote Periodontal Regeneration. Tissue Eng Part A. 2021;27(13–14):962–76.

    PubMed  Google Scholar 

  42. Shen Z, Kuang S, Zhang Y, Yang M, Qin W, Shi X, Lin Z. Chitosan hydrogel incorporated with dental pulp stem cell-derived exosomes alleviates periodontitis in mice via a macrophage-dependent mechanism. Bioact Mater. 2020;5(4):1113–26.

    PubMed  PubMed Central  Google Scholar 

  43. Wei J, Song Y, Du Z, Yu F, Zhang Y, Jiang N, Ge X. Exosomes derived from human exfoliated deciduous teeth ameliorate adult bone loss in mice through promoting osteogenesis. J Mol Histol. 2020;51(4):455–66.

    PubMed  Google Scholar 

  44. Hayrapetyan A, Jansen JA, van den Beucken JJ. Signaling pathways involved in osteogenesis and their application for bone regenerative medicine. Tissue Eng Part B Rev. 2015;21(1):75–87.

    PubMed  Google Scholar 

  45. Tréton G, Sayer C, Schürz M, Jaritsch M, Mueller A, Matea CT, Stanojlovic V, Melo-Benirschke H, Be C, Krembel C, Rodde S, Haffke M, Hintermann S, Marzinzik A, Ripoche S, Blöchl C, Hollerweger J, Auer D, Cabrele C, Huber CG, Hintersteiner M, Wagner T, Lingel A, Meisner-Kober N. Quantitative and functional characterisation of extracellular vesicles after passive loading with hydrophobic or cholesterol-tagged small molecules. J Control Release. 2023 Aug 9:S0168-3659(23)00506-0.

  46. Li Q, Fu X, Kou Y, Han N. Engineering strategies and optimized delivery of exosomes for theranostic application in nerve tissue. Theranostics. 2023;13(12):4266–86.

    PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

Not applicable.

Funding

This study was supported by the National Natural Science Foundation of China (82170927, 82071078 and 82201066), and Natural Science Fund basic research program of Shaanxi Province (2022JQ-772).

Author information

Author notes

  1. Huan Zhou and Yan-Xin Qi contributed equally to this work.

Authors and Affiliations

  1. Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an, China

    Huan Zhou, Yan-Xin Qi, Chun-Hui Zhu, Ang Li & Dan-Dan Pei

  2. Department of Periodontology, College of Stomatology, Xi’an Jiaotong University, Xi’an, China

    Huan Zhou, Chun-Hui Zhu & Ang Li

  3. Department of Prosthodontics, College of Stomatology, Xi’an Jiaotong University, Xi’an, China

    Yan-Xin Qi & Dan-Dan Pei

Authors
  1. Huan Zhou
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yan-Xin Qi
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Chun-Hui Zhu
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Ang Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Dan-Dan Pei
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

A.L. and D.D.P. designed the reasearch. H.Z. and Y.X.Q. did the literature search. Y.X.Q., D.D.P. and A.L. reviewed the publications. H.Z. and Y.X.Q. extracted the data. Y.X.Q. and C.H.Z. did the data analysis. H.Z. and Y.X.Q. wrote the paper. A.L. and D.D.P. revised the manuscript; All authors have read and agreed to the published version of the manuscript.

Corresponding authors

Correspondence to Ang Li or Dan-Dan Pei.

Ethics declarations

Competing interests

The authors declare no competing interests.

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary Material 1

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zhou, H., Qi, YX., Zhu, CH. et al. Mesenchymal stem cell-derived extracellular vesicles for treatment of bone loss within periodontitis in pre-clinical animal models: a meta-analysis. BMC Oral Health 23, 701 (2023). https://doi.org/10.1186/s12903-023-03398-w

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12903-023-03398-w

Keywords

BMC Oral Health

ISSN: 1472-6831

Contact us