Dental pulp stem cell-derived exosomes alleviate cerebral ischaemia-reperfusion injury through suppressing inflammatory response

Engineering hirudin encapsulation in pH-responsive antioxidant nanoparticles for therapeutic efficacy in ischemic stroke model mice

This study introduces a novel pH-sensitive, hirudin-loaded antioxidant nanoparticle (HD@iNanoAOX) aimed at addressing the challenges of hirudin's short half-life and hemorrhagic transformation. HD@iNanoAOX was engineered to safeguard and prolong hirudin's bioactivity by encapsulating it within antioxidative nanoparticles, facilitating its gradual release in acidic environments. The efficacy of this approach was validated through both ex vivo and in vivo experiments. Ex vivo thrombolytic assays demonstrated that HD@iNanoAOX maintained effective clot lysis activity under acidic conditions. In vivo assessments revealed that HD@iNanoAOX significantly prolonged hirudin's half-life and reduced cerebral infarct volume in a mouse model of middle cerebral artery occlusion (MCAO). Furthermore, HD@iNanoAOX treatment mitigated cerebral oxidative stress, suppressed hemorrhagic transformation, and prevented blood-brain barrier (BBB) disruption. These findings suggest that the combined thrombolytic and antioxidative properties of HD@iNanoAOX offer a promising therapeutic approach for ischemic stroke. Nonetheless, further research is warranted to optimize the formulation and assess its safety and efficacy in clinical settings.

Dental Pulp Stem Cells Attenuate Early Brain Injury After Subarachnoid Hemorrhage via miR-26a-5p/PTEN/AKT Pathway

Subarachnoid hemorrhage (SAH) is a type of hemorrhagic stroke with high morbidity, mortality and disability, and early brain injury (EBI) after SAH is crucial for prognosis. Recently, stem cell therapy has garnered significant attention in the treatment of neurological diseases. Compared to other stem cells, dental pulp stem cells (DPSCs) possess several advantages, including abundant sources, absence of ethical concerns, non-invasive procurement, non-tumorigenic history and neuroprotective potential. Therefore, we aim to investigate whether DPSCs can improve EBI after SAH, and explore the mechanisms. In our study, we utilized the endovascular perforation method to establish a SAH mouse model and investigated whether DPSCs administered via tail vein injection could improve EBI after SAH. Furthermore, we used hemin-stimulated HT22 cells to simulate neuronal cell injury induced by SAH and employed a co-culture approach to examine the effects of DPSCs on these cells. To gain insights into the potential mechanisms underlying the improvement of SAH-induced EBI by DPSCs, we conducted bioinformatics analysis. Finally, we further validated our findings through experiments. In vivo experiments, we found that DPSCs administration improved neurological dysfunction, reduced brain edema, and prevented neuronal apoptosis in SAH mice. Additionally, we observed a decrease in the expression level of miR-26a-5p in the cortical tissues of SAH mice, which was significantly increased following intravenous injection of DPSCs. Through bioinformatic analysis and luciferase reporter assay, we confirmed the target relationship between miR-26a-5p and PTEN. Moreover, we demonstrated that DPSCs exerted neuroprotective effects by modulating the miR-26a-5p/PTEN/AKT pathway. Our study demonstrates that DPSCs can improve EBI after SAH through the miR-26a-5p/PTEN/AKT pathway, laying a foundation for the application of DPSCs in SAH treatment. These findings provide a theoretical basis for further investigating the therapeutic mechanisms of DPSCs and developing novel treatment strategies in SAH.

Stem Cell-Derived Extracellular Vesicle-Mediated Therapeutic Signaling in Spinal Cord Injury

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as a promising therapeutic strategy for spinal cord injury (SCI). These nanosized vesicles possess unique properties such as low immunogenicity and the ability to cross biological barriers, making them ideal carriers for delivering bioactive molecules to injured tissues. MSC-EVs have been demonstrated to exert multiple beneficial effects in SCI, including reducing inflammation, promoting neuroprotection, and enhancing axonal regeneration. Recent studies have delved into the molecular mechanisms underlying MSC-EV-mediated therapeutic effects. Exosomal microRNAs (miRNAs) have been identified as key regulators of various cellular processes involved in SCI pathogenesis and repair. These miRNAs can influence inflammation, oxidative stress, and apoptosis by modulating gene expression. This review summarized the current state of MSC-EV-based therapies for SCI, highlighting the underlying mechanisms and potential clinical applications. We discussed the challenges and limitations of translating these therapies into clinical practice, such as inconsistent EV production, complex cargo composition, and the need for targeted delivery strategies. Future research should focus on optimizing EV production and characterization, identifying key therapeutic miRNAs, and developing innovative delivery systems to maximize the therapeutic potential of MSC-EVs in SCI.

An Optimized Decellularized Extracellular Matrix from Dental Pulp Stem Cell Sheets Promotes Axonal Regeneration by Multiple Modes in Spinal Cord Injury Rats

In the field of tissue engineering, the extracellular matrix (ECM) is considered an important element for promoting neural regeneration after spinal cord injury (SCI). Dental pulp stem cells (DPSCs), mesenchymal stem cells that originate from the neural crest, are easy to harvest and culture in vitro, express a variety of neurotrophic factors (NTFs) and deposit a large amount of ECM, making them a good choice for stem cell- or ECM-based treatment of SCI. In the present study, decellularized extracellular matrix (dECM) derived from DPSC sheets is used for the treatment of SCI. Optimization experiments reveal that incubating DPSC sheets with 1% Triton X-100 for 5 min is the best procedure for preparing DPSC dECM. It is found that DPSC dECM promotes nerve repair and regeneration after SCI and restores hindlimb motor function in rats. Mechanistically, DPSC dECM facilitates the migration and neural differentiation of neural stem cells, as well as M2 polarization of microglia, and inhibits the formation of glial scars. This study suggests that the use of DPSC dECM is a potential strategy for the treatment of SCI.

Dental pulp stem cells derived exosomes inhibit ferroptosis via regulating the Nrf2-keap1/GPX4 signaling pathway to ameliorate chronic kidney disease injury

INTRODUCTION

Chronic kidney disease (CKD) has long represented a substantial global health challenge. Regrettably, current therapeutic interventions exhibit limited efficacy in halting the progression of CKD. Ferroptosis may play a crucial role in CKD, as indicated by substantial evidence. Dental pulp stem cell-derived exosomes (DPSC-Exos) possess advantages such as abundant sources and low immunogenicity, holding promising prospects in CKD treatment.

METHODS

This study constructed a mouse CKD model to investigate the therapeutic effects of DPSC-Exos. First, we successfully extracted and identified DPSC-Exos. Then, mice were randomly divided into sham, PBS, CKD, and CKD+Exos groups. Our study determined the expression of ferroptosis-related pathway molecules Nrf2, GPX4, Keap1, and HO-1 in each group. Finally, we detected the expression levels of inflammatory factors, TNF-α, IL-1β, and IL-6, at the injury site.

RESULTS

Mice treated with DPSC-Exos showed increased expression of the ferroptosis inhibitory factor Nrf2 and its downstream regulatory factors GPX4 and HO-1, while the expression of Keap1 decreased. The expression of TNF-α, IL-1β, and IL-6 also decreased.

CONCLUSION

DPSC-Exos may help inhibit ferroptosis through the Keap1-Nrf2/GPX4 pathway and reduce the inflammatory response at the injury site, revealing their potential therapeutic effects on CKD.

Engineered exosome therapeutics for neurodegenerative diseases

An increase in life expectancy comes with a higher risk for age-related neurological and cognitive dysfunctions. Given the psycho-socioeconomic burden due to unhealthy aging in the coming decades, the United Nations has declared 2021-2030 as a decade of healthy aging. In this line, multipotent mesenchymal stromal cell-based therapeutics received special interest from the research community. Based on decades of research on cell therapy, a consensus has emerged that the therapeutic effects of cell therapy are due to the paracrine mechanisms rather than cell replacement. Exosomes, a constituent of the secretome, are nano-sized vesicles that have been a focus of intense research in recent years as a possible therapeutic agent or as a cargo to deliver drugs of interest into the central nervous system to induce neurogenesis, reduce neuroinflammation, confer neuroregeneration/neuroprotection, and improve cognitive and motor functions. In this review, we have discussed the neuroprotective properties of exosomes derived from adult mesenchymal stem cells, with a special focus on the role of exosomal miRNAs. We also reviewed various strategies to improve exosome production and their content for better therapeutic effects. Further, we discussed the utilization of ectomesenchymal stem cells like dental pulp stem cells and their exosomes in treating neurodegenerative diseases.

The Role of Dental-derived Stem Cell-based Therapy and Their Derived Extracellular Vesicles in Post-COVID-19 Syndrome-induced Tissue Damage

Long coronavirus disease 2019 (COVID-19) is linked to an increased risk of post-acute sequelae affecting the pulmonary and extrapulmonary organ systems. Up to 20% of COVID-19 patients may proceed to a more serious form, such as severe pneumonia, acute respiratory distress syndrome (ARDS), or pulmonary fibrosis. Still, the majority of patients may only have mild, self-limiting sickness. Of particular concern is the possibility of parenchymal fibrosis and lung dysfunction in long-term COVID-19 patients. Furthermore, it has been observed that up to 43% of individuals hospitalized with COVID-19 also had acute renal injury (AKI). Care for kidney, brain, lung, cardiovascular, liver, ocular, and tissue injuries should be included in post-acute COVID-19 treatment. As a powerful immunomodulatory tool in regenerative medicine, dental stem cells (DSCs) have drawn much interest. Numerous immune cells and cytokines are involved in the excessive inflammatory response, which also has a significant effect on tissue regeneration. A unique reservoir of stem cells (SCs) for treating acute lung injury (ALI), liver damage, neurological diseases, cardiovascular issues, and renal damage may be found in tooth tissue, according to much research. Moreover, a growing corpus of in vivo research is connecting DSC-derived extracellular vesicles (DSC-EVs), which are essential paracrine effectors, to the beneficial effects of DSCs. DSC-EVs, which contain bioactive components and therapeutic potential in certain disorders, have been shown as potentially effective therapies for tissue damage after COVID-19. Consequently, we explore the properties of DSCs in this work. Next, we'll look at how SARS-CoV-2 affects tissue damage. Lastly, we have looked at the use of DSCs and DSC-EVs in managing COVID-19 and chronic tissue damage, such as injury to the heart, brain, lung, and other tissues.

Stem cell-derived exosomes for ischemic stroke: a conventional and network meta-analysis based on animal models

Objective

We aimed to evaluate the efficacy of stem cell-derived exosomes for treating ischemic stroke and to screen for the optimal administration strategy.

Methods

We searched PubMed, Web of Science, Embase, Cochrane Library, and Scopus databases for relevant studies published from their inception to 31 December 2023. Conventional and network meta-analyses of the routes of administration, types, and immune compatibility of stem cell-derived exosomes were performed using the cerebral infarct volume (%) and modified neurological severity score (mNSS) as outcome indicators.

Results

A total of 38 randomized controlled animal experiments were included. Conventional meta-analysis showed that compared with the negative control group: intravenous administration significantly reduced the cerebral infarct volume (%) and mNSS; intranasal administration significantly reduced the cerebral infarct volume (%); and intracerebral administration significantly reduced the mNSS. Adipose-derived mesenchymal stem cell-derived exosomes (ADSC-Exos), bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exos), dental pulp stem cell-derived exosomes (DPSC-Exos) and neural stem cell-derived exosomes (NSC-Exos) significantly reduced the cerebral infarct volume (%) and mNSS; Endothelial progenitor cell-derived exosomes (EPC-Exos), embryonic stem cell-derived exosomes (ESC-Exos), induced pluripotent stem cell-derived exosomes (iPSC-Exos) and neural progenitor cell-derived exosomes (NPC-Exos) significantly reduced the cerebral infarct volume (%); Umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-Exos) significantly reduced the mNSS; and there was no significant difference between urogenital stem cell-derived exosomes (USC-Exos) and negative controls. Engineered modified exosomes had better efficacy than unmodified exosomes. Both allogeneic and xenogeneic stem cell-derived exosomes significantly reduced the cerebral infarct volume (%) and the mNSS. The network meta-analysis showed that intravenous administration was the best route of administration for reducing the cerebral infarct volume (%) and mNSS. Among the 10 types of stem cell-derived exosomes that were administered intravenously, BMSC-Exos were the best type for reducing the cerebral infarct volume (%) and the mNSS. Allogeneic exosomes had the best efficacy in reducing the cerebral infarct volume (%), whereas xenogeneic stem cell-derived exosomes had the best efficacy in reducing the mNSS.

Conclusion

This meta-analysis, by integrating the available evidence, revealed that intravenous administration is the best route of administration, that BMSC-Exos are the best exosome type, that allogeneic exosomes have the best efficacy in reducing the cerebral infarct volume (%), and that xenogeneic exosomes have the best efficacy in reducing mNSS, which can provide options for preclinical studies. In the future, more high-quality randomized controlled animal experiments, especially direct comparative evidence, are needed to determine the optimal administration strategy for stem cell-derived exosomes for ischemic stroke.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42024497333, PROSPERO, CRD42024497333.

Exosome-related gene identification and diagnostic model construction in hepatic ischemia-reperfusion injury

Hepatic ischemia-reperfusion injury (HIRI) may cause severe hepatic impairment, acute hepatic insufficiency, and multiorgan system collapse. Exosomes can alleviate HIRI. Therefore, this study explored the role of exosomal-related genes (ERGs) in HIRI using bioinformatics to determine the underlying molecular mechanisms and novel diagnostic markers for HIRI. We merged the GSE12720, GSE14951, and GSE15480 datasets obtained from the Gene Expression Omnibus (GEO) database into a combined gene dataset (CGD). CGD was used to identify differentially expressed genes (DEGs) based on a comparison of the HIRI and healthy control cohorts. The impact of these DEGs on HIRI was assessed through gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA). ERGs were retrieved from the GeneCards database and prior studies, and overlapped with the identified DEGs to yield the set of exosome-related differentially expressed genes (ERDEGs). Functional annotations and enrichment pathways of these genes were determined using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Diagnostic models for HIRI were developed using least absolute shrinkage and selection operator (LASSO) regression and support vector machine (SVM) algorithms. Key genes with diagnostic value were identified from the overlap, and single-sample gene-set enrichment analysis (ssGSEA) was conducted to evaluate the immune infiltration characteristics. A molecular regulatory interaction network was established using Cytoscape software to elucidate the intricate regulatory mechanisms of key genes in HIRI. Finally, exosome score (Es) was obtained using ssGSEA and the HIRI group was divided into the Es_High and Es_Low groups based on the median Es. Gene expression was analyzed to understand the impact of all genes in the CGD on HIRI. Finally, the relative expression levels of the five key genes in the hypoxia-reoxygenation (H/R) model were determined using quantitative real-time PCR (qRT-PCR). A total of 3810 DEGs were identified through differential expression analysis of the CGD, and 61 of these ERDEGs were screened. Based on GO and KEGG enrichment analyses, the ERDEGs were mainly enriched in wound healing, MAPK, protein kinase B signaling, and other pathways. GSEA and GSVA revealed that these genes were mainly enriched in the TP53, MAPK, TGF[Formula: see text], JAK-STAT, MAPK, and NFKB pathways. Five key genes (ANXA1, HNRNPA2B1, ICAM1, PTEN, and THBS1) with diagnostic value were screened using the LASSO regression and SVM algorithms and their molecular interaction network was established using Cytoscape software. Based on ssGSEA, substantial variations were found in the expression of 18 immune cell types among the groups (p < 0.05). Finally, the Es of each HIRI patient was calculated. ERDEGs in the Es_High and Es_Low groups were enriched in the IL18, TP53, MAPK, TGF[Formula: see text], and JAK-STAT pathways. The differential expression of these five key genes in the H/R model was verified using qRT-PCR. Herein, five key genes were identified as potential diagnostic markers. Moreover, the potential impact of these genes on pathways and the regulatory mechanisms of their interaction network in HIRI were revealed. Altogether, our findings may serve as a theoretical foundation for enhancing clinical diagnosis and elucidating underlying pathogeneses.

Umbilical cord blood-derived exosomes attenuate dopaminergic neuron damage of Parkinson's disease mouse model

BACKGROUND

Umbilical cord blood (UCB) is a rich source of multifunctional stem cells characterized by low immunogenicity. Recent research in the fields of aging and regenerative medicine has revealed the potential of human umbilical cord blood-derived exosomes (UCB-Exos) in promoting wound healing, anti-aging, and regeneration. However, their role in neurodegenerative diseases, specifically Parkinson's disease (PD), remains unexplored. This study investigates the potential therapeutic effects and underlying mechanisms of UCB-Exos on PD.

METHODS

Large extracellular vesicles (LEv), Exos, and soluble fractions (SF) of human UCB plasma were extracted to investigate their effects on motor dysfunction of the MPTP-induced PD mouse model and identify the key components that improve PD symptoms. UCB-Exos were administered by the caudal vein to prevent or treat the PD mouse model. The motor function and pathological markers were detected. Differentially expressed gene and KEGG enrichment pathways were screened by transcriptome sequence. MN9D and SH-SY5Y cells were cultured and evaluated for cell viability, oxidative stress, cell cycle, and aging-related indexes by qRT-PCR, western blot, immunofluorescence, and flow cytometry. The protein expression level of the MAPK p38 and ERK1/2 signaling pathway was detected by western blot.

RESULTS

We observed that LEv, Exos, and SF all exhibited potential in ameliorating motor dysfunction in MPTP-induced PD model mice, with UCB-Exos demonstrating the most significant effect. UCB-Exos showed comparable efficacy in preventing and treating motor dysfunction, cognitive decline, and substantia nigra pathological damage in PD mice. Further investigations revealed that UCB-Exos could potentially alleviate oxidative damage, aging and degeneration, and energy metabolism disorders in neurons. Transcriptome sequencing results corroborated that genes differentially expressed due to UCB-Exos were primarily enriched in the neuroactive ligand-receptor interaction, Dopaminergic synapse, and MAPK signaling pathway. We also observed that UCB-Exos significantly inhibited the hyperphosphorylation of the MAPK p38 and ERK1/2 signaling pathways both in vitro and in vivo.

CONCLUSIONS

Our study provides a comprehensive evaluation of UCB-Exos on the neuroprotective effects and suggests that inhibition of hyperphosphorylation of MAPK p38 and ERK 1/2 signaling pathways by regulating transcription levels of HspB1 and Ppef2 may be the key mechanism for UCB-Exos to improve PD-related pathological features.

Dental Stem Cell-Derived Exosomes: A Review of Their Isolation, Classification, Functions, and Mechanisms

The scientific field concerned with the study of regeneration has developed rapidly in recent years. Stem cell therapy is a highly promising therapeutic modality for repairing tissue defects; however, several limitations exist, such as cytotoxicity, potential immune rejection, and ethical issues. Exosomes secreted by stem cells are cell-specific secreted vesicles that play a regulatory role in many biological functions in the human body; they not only have a series of functional roles of stem cells and exert the expected therapeutic effects, but they can also overcome the mass limitations of stem cells and are thus considered in the research as an alternative treatment strategy for stem cells. Since dental stem cell-derived exosomes (DSC-Exos) are easy to acquire and present modulating effects in several fields, including neurovascular regeneration and craniofacial soft and hard tissue regeneration processes, they are served as an emerging cell-free therapeutic strategy in various systematic diseases. There is a growing body of research on various types of DSC-Exos; however, they lack systematic elaboration and tabular summarization. Therefore, this review presents the isolation, characterization, and phenotypes of DSC-Exos and focuses on their current status of functions and mechanisms, as well as the multiple challenges prior to clinical applications.

Dental pulp stem cells regenerate neural tissue in degenerative disorders and stroke rehabilitation: A scope systematic review

Background

Dental Pulp Stem Cells (DPSCs) possess a remarkable ability for tissue differentiation, making them highly efficient in tissue regeneration and inflammation regulation. This systematic study proposes to find an answer to the question, "Do DPSCs have the ability to regenerate and rehabilitate nerve tissue?"

Methods

This systematic review was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, and the principle of non-bias was respected. All the articles from 2014 to 2024 were extracted from the Web of Science, PubMed, and Scopus databases. This study extracted the antigens and pro-inflammatory factors associated with DPSCs' involvement and how they affect the CNS's neural tissue regeneration.

Results

Two persons of researchers searched the database. After screening the full texts, they included 11 articles in their study. DPSCs control the following antigens: CD73, CD34, CD90, CD105, CD14, CD45, CD19Oct-4, CD73, CD31, CD34CD29CD44. Even though hematopoietic markers did not change much, OCT-4 and CD-73 were increased by DPSCs. DPSC-derived exosomes suppressed the expression of IL-6, IL-1β, TNF-α, and TGF, key mediators of nerve tissue inflammation. Additionally, DPSCs show high Vascular Endothelial Growth Factor (VEGF) expression in mice brain tissue cultures. DPSCs reduce Subarachnoid Hemorrhage (SAH), a condition in which blood collects in the subarachnoid space and causes ischemia.

Discussion

DPSCs showed the ability to regenerate nerve tissue and brain ganglia, stimulating angiogenesis by expressing cell markers and controlling growth factors in mice, and high therapeutic potential in neurodegenerative disorders. The present study invites further research in neurological disorders, specifically strokes, to prescribe these stem cells to the human population.

Baicalin-loaded Polydopamine modified ZIF-8 NPs inhibits myocardial ischemia/reperfusion injury in rats

Baicalin (BAN) has shown promise in alleviating myocardial ischemia/reperfusion (I/R) injury, yet its limited solubility and biocompatibility have hindered its application. Developing drug delivery systems is a promising strategy to enhance the therapeutic potential of BAN in the context of I/R injury. This study aims to prepare a BAN-loaded nanodrug system using polydopamine (PDA)-modified Zeolitic imidazolate framework-8 (ZIF-8) as a carrier, with the goal of improving BAN's mitigating effects on I/R injury. We prepared the BAN nanoparticles (NPs) system, PZB NPs, using ZIF-8 as the carrier. The system was characterized in terms of morphology, particle size, zeta potential, and X-ray diffraction (XRD). We assessed the cytotoxicity of PZB NPs in H9c2 cells, investigated its effects and mechanisms in H/R-induced H9c2 cells, and evaluated its ability to alleviate myocardial I/R injury in rats. PZB NPs exhibited good dispersion, with a BAN loading efficiency of 26.43 ± 1.55%, a hydrated particle size of 102.21 ± 1.19 nm, and a zeta potential of -24.84 ± 0.07 mV. It displayed slow and sustained drug release in an acidic environment (pH 5.5). In vitro studies revealed that PZB NPs was non-cytotoxic and significantly enhanced the recovery of H/R injury H9c2 cell viability. PZB NPs suppressed cell apoptosis, activated the Nrf2/HO-1 pathway, and cleared ROS. In vivo study demonstrated that PZB NPs significantly reduced infarct size, ameliorated fibrosis and improved heart function. The PZB NPs markedly enhances BAN's ability to alleviate I/R injury, both in vitro and in vivo, offering a promising drug delivery system for clinical applications.

Therapeutic impacts of GNE‑477‑loaded H2O2 stimulus‑responsive dodecanoic acid‑phenylborate ester‑dextran polymeric micelles on osteosarcoma

Osteosarcoma (OS) is a highly malignant primary bone neoplasm that is the leading cause of cancer‑associated death in young people. GNE‑477 belongs to the second generation of mTOR inhibitors and possesses promising potential in the treatment of OS but dose tolerance and drug toxicity limit its development and utilization. The present study aimed to prepare a novel H2O2 stimulus‑responsive dodecanoic acid (DA)‑phenylborate ester‑dextran (DA‑B‑DEX) polymeric micelle delivery system for GNE‑477 and evaluate its efficacy. The polymer micelles were characterized by morphology, size and critical micelle concentration. The GNE‑477 loaded DA‑B‑DEX (GNE‑477@DBD) tumor‑targeting drug delivery system was established and the release of GNE‑477 was measured. The cellular uptake of GNE‑477@DBD by three OS cell lines (MG‑63, U2OS and 143B cells) was analyzed utilizing a fluorescent tracer technique. The hydroxylated DA‑B was successfully grafted onto dextran at a grafting rate of 3%, suitable for forming amphiphilic micelles. Following exposure to H2O2, the DA‑B‑DEX micelles ruptured and released the drug rapidly, leading to increased uptake of GNE‑477@DBD by cells with sustained release of GNE‑477. The in vitro experiments, including MTT assay, flow cytometry, western blotting and RT‑qPCR, demonstrated that GNE‑477@DBD inhibited tumor cell viability, arrested cell cycle in G1 phase, induced apoptosis and blocked the PI3K/Akt/mTOR cascade response. In vivo, through the observation of mice tumor growth and the results of H&E staining, the GNE‑477@DBD group exhibited more positive therapeutic outcomes than the free drug group with almost no adverse effects on other organs. In conclusion, H2O2‑responsive DA‑B‑DEX presents a promising delivery system for hydrophobic anti‑tumor drugs for OS therapy.

Transfer of miR-877-3p via extracellular vesicles derived from dental pulp stem cells attenuates neuronal apoptosis and facilitates early neurological functional recovery after cerebral ischemia-reperfusion injury through the Bclaf1/P53 signaling pathway

Cerebral ischemia-reperfusion injury (I/RI) is one of the principal pathogenic factors in the poor prognosis of ischemic stroke, for which current therapeutic options to enhance neurological recovery are notably insufficient. Dental pulp stem cell-derived extracellular vesicles (DPSC-EVs) have promising prospects in stroke treatment and the specific underlying mechanisms have yet to be fully elucidated. The present study observed that DPSC-EVs ameliorated the degree of cerebral edema and infarct volume by reducing the apoptosis of neurons. Furthermore, the miRNA sequencing and functional enrichment analysis identified that miR-877-3p as a key component in DPSC-EVs, contributing to neuroprotection and anti-apoptotic effects. Following target prediction and dual-luciferase assay indicated that miR-877-3p interacted with Bcl-2-associated transcription factor (Bclaf1) to play a function. The miR-877-3p inhibitor or Bclaf1 overexpression reversed the neuroprotective effects of DPSC-EVs. The findings reveal a novel therapeutic pathway where miR-877-3p, transferred via DPSC-EVs, confers neuroprotection against cerebral I/RI, highlighting its potential in promoting neuronal survival and recovery post-ischemia.

Photosensitive Hydrogels Encapsulating DPSCs and AgNPs for Dental Pulp Regeneration

OBJECTIVE

Pulp regeneration with bioactive dentin-pulp complex has been a research hotspot in recent years. Stem cell therapy provided an interest strategy to regenerate the dental-pulp complex. Hence, this study aimed to evaluate the effects of photosensitive gelatin methacrylate (GelMA) hydrogel encapsulating dental pulp stem cells (DPSCs) and silver nanoparticles (AgNPs) for dental pulp regeneration in vitro.

METHODS

First, the AgNPs@GelMA hydrogels were prepared by lithium phenyl-2,4,6-trimethyl-benzoyl phosphinate (LAP) initiation via blue-light emitting diode light. The physical and chemical properties of AgNPs@GelMA hydrogels were comprehensively analysed via scanning electron microscopy (SEM), and mechanical characterisation, such as swelling ability, degradation properties, and AgNP release profile. Then, AgNPs@GelMA hydrogels encapsulated DPSCs were used to establish an AgNPs@GelMA biomimetic complex, further analysing its biocompatibility, antibacterial properties, and angiogenic capacity in vitro.

RESULTS

The results indicated that GelMA hydrogels demontrated optimal characteristics with a monomer:LAP ratio of 16:1. The physico-chemical properties of AgNPs@GelMA hydrogels did not change significantly after loading with AgNPs. There was no significant difference in AgNP release rate amongst different concentrations of AgNPs@GelMA hydrogels. Fifty to 200 μg/mL AgNPs@GelMA hydrogels could disperse E faecalis biofilm and reduce its metabolic activity . Furthermore, cell proliferation was arrested in 100 and 200 μg/mL AgNPs@GelMA hydrogels. The inhibition of 50 μg/mL AgNPs@GelMA hydrogels on E faecalis biofilm was above 50%, and the cell viability of the hydrogels was higher than 90%. The angiogenesis assay indicated that AgNPs@GelMA hydrogels encapsulating DPSCs could induce the formation of capillary-like structures and express angiogenic markers CD31, vascular endothelial growth factor , and von willebrand factor (vWF) in vitro.

CONCLUSIONS

Results of this study indicate that 50 μg/mL AgNPs@GelMA hydrogels encapsulating DPSCs had significant antibacterial properties and angiogenic capacity, which could provide a significant experimental basis for the regeneration of the dentin-pulp complex.

Effects of extracellular vesicles for ischemic stroke: A meta‑analysis of preclinical studies

Ischemic stroke is a common occurrence worldwide, posing a severe threat to human health and leading to negative financial impacts. Currently available treatments still have numerous limitations. As research progresses, extracellular vesicles are being found to have therapeutic potential in ischemic stroke. In the present study, the literature on extracellular vesicle therapy in animal studies of ischemic stroke was screened by searching databases, including PubMed, Embase, Medline, Web of Science and the Cochrane Library. The main outcomes of the present study were the neurological function score, apoptotic rate and infarct volumes. The secondary outcomes were pro-inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. The study quality was assessed using the CAMARADES Checklist. Subgroup analyses were performed to evaluate factors influencing extracellular vesicle therapy. Review Man3ager5.3 was used for data analysis. A total of 20 relevant articles were included in the present meta-analysis. The comprehensive analysis revealed that extracellular vesicles exerted a significant beneficial effect on neurobehavioral function, reducing the infarct volume and decreasing the apoptotic rate. Moreover, extracellular vesicles were found to promote nerve recovery by inhibiting pro-inflammatory factors (TNF-α, IL-1β and IL-6). On the whole, the present meta-analysis examined the combined effects of extracellular vesicles on nerve function, infarct volume, apoptosis and inflammation, which provides a foundation for the clinical study of extracellular vesicles.

A new subtype of artificial cell-derived vesicles from dental pulp stem cells with the bioequivalence and higher acquisition efficiency compared to extracellular vesicles

Extracellular vesicles (EVs) derived from dental pulp stem cells (DPSC) have been shown an excellent efficacy in a variety of disease models. However, current production methods fail to meet the needs of clinical treatment. In this study, we present an innovative approach to substantially enhance the production of 'Artificial Cell-Derived Vesicles (ACDVs)' by extracting and purifying the contents released by the DPSC lysate, namely intracellular vesicles. Comparative analysis was performed between ACDVs and those obtained through ultracentrifugation. The ACDVs extracted from the cell lysate meet the general standard of EVs and have similar protein secretion profile. The new ACDVs also significantly promoted wound healing, increased or decreased collagen regeneration, and reduced the production of inflammatory factors as the EVs. More importantly, the extraction efficiency is improved by 16 times compared with the EVs extracted using ultracentrifuge method. With its impressive attributes, this new subtype of ACDVs emerge as a prospective candidate for the future clinical applications in regenerative medicine.

Andrographolide induces protective autophagy and targeting DJ-1 triggers reactive oxygen species-induced cell death in pancreatic cancer

Background

Andrographolide (Andro), an extract of Andrographis paniculate (Burm.f.) Wall. ex Nees (Acanthaceae), possesses diverse biologically active properties. However, the precise mechanisms and effects of Andro on pancreatic cancer (PC) remain unclear.

Methods

The cytotoxic potential of Andro and underlying mechanism towards PC cells was investigated through in vitro experiments and a xenograft mouse model. PC cells were first subjected to varying concentrations of Andro. The reactive oxygen species (ROS) was assessed using flow cytometry and DCFH-DA staining. The apoptosis rate was detected by flow cytometry. Additionally, western blot was applied to evaluate the expression levels of cleaved-caspase-3, DJ-1, LC3-I, LC3-II, and p62. To further elucidate the involvement of ROS accumulation and autophagy, we employed N-acetylcysteine as a scavenger of ROS and 3-Methyladenine as an inhibitor of autophagy.

Results

Andro demonstrated potent anti-proliferative effects on PC cells and induced apoptosis, both in vitro and in vivo. The cytotoxicity of Andro on PC cells was counteracted by DJ-1 overexpression. The reduction in DJ-1 expression caused by Andro led to ROS accumulation, subsequently inhibiting the growth of PC cells. Furthermore, Andro stimulated cytoprotective autophagy, thus weakening the antitumor effect. Pharmacological blockade of autophagy further enhanced the antitumor efficacy of Andro.

Conclusion

Our study indicated that ROS accumulation induced by the DJ-1 reduction played a key role in Andro-mediated PC cell inhibition. Furthermore, the protective autophagy induced by the Andro in PC cells is a mechanism that needs to be addressed in future studies.

Discovery of sesquiterpenoids from the roots of Chloranthus henryi Hemsl. var. hupehensis (Pamp.) K. F. Wu and their anti-inflammatory activity by IKBα/NF-κB p65 signaling pathway suppression

Phytochemical analysis of Chloranthus henryi var. hupehensis roots led to the identification of a new eudesmane sesquiterpenoid dimer, 18 new sesquiterpenoids, and three known sesquiterpenoids. Among the isolates, 1 was a rare sesquiterpenoid dimer that is assembled by a unique oxygen bridge (C11-O-C8') of two highly rearranged eudesmane-type sesquiterpenes with the undescribed C16 carbon framework. (+)-2 and (-)-2 were a pair of new skeleton dinorsesquiterpenoids with a remarkable 6/6/5 tricyclic ring framework including one γ-lactone ring and the bicyclo[3.3.1]nonane core. Their structures were elucidated using spectroscopic data, single-crystal X-ray diffraction analysis, and quantum chemical computations. In the LPS-induced BV-2 microglial cell model, 17 suppressed IL-1β and TNF-α expression with EC50 values of 6.81 and 2.76 µM, respectively, indicating its excellent efficacy in inhibiting inflammatory factors production in a dose dependent manner and without cytotoxicity. In subsequent mechanism studies, compounds 3, 16, and 17 could reduce IL-1β and TNF-α production by inhibiting IKBα/p65 pathway activation.

The potential therapeutic roles of dental pulp stem cells in spinal cord injury

Spinal cord injury (SCI) can lead to serious functional disorders, which have serious impacts on patients and society. The current traditional treatments of SCI are not effective the injured spinal cord is difficult to repair and regenerate. In recent years, stem cell transplantation for the treatment of SCI has been a hot research topic. Dental pulp stem cells have strong abilities of self-renewal and multi-directional differentiation, and have been applied for tissue engineering and regenerative medicine. And dental pulp stem cells have certain advantages in neuro-regenetation, bringing new hope to biotherapy for SCI. This article reviews the characteristics of dental pulp stem cells and their research progress in the treatment of SCI.

Molecular network mechanism in cerebral ischemia-reperfusion rats treated with human urine stem cells

Objective

To explore the effect of human urine-derived stem cells (husc) in improving the neurological function of rats with cerebral ischemia-reperfusion (CIR), and report new molecular network by bioinformatics, combined with experiment validation.

Methods

After CIR model was established, and husc were transplanted into the lateral ventricle of rats，neurological severe score (NSS) andgene network analysis were performed. Firstly, we input the keywords "Cerebral reperfusion" and "human urine stem cells" into Genecard database and merged data with findings from PubMed so as to get their targets genes, and downloaded them to make Venny intersection plot. Then, Gene ontology (GO) analysis, kyoto encyclopedia of genes and genomes (KEGG) pathway analysis and protein-protein interaction (PPI) were performed to construct molecular network of core genes. Lastly, the expressional level of core genes was validated via quantitative real-time polymerase chain reaction (qRT-PCR), and localized by immunofluorescence.

Results

Compared with the Sham group, the neurological function of CIR rats was significantly improved after the injection of husc into the lateral ventricle; at 14 days, P = 0.028, which was statistically significant. There were 258 overlapping genes between CIR and husc, and integrated with 252 genes screened from PubMed and CNKI. GO enrichment analysis were mainly involved neutrophil degranulation, neutrophil activation in immune response and platelet positive regulation of degranulation, Hemostasis, blood coagulation, coagulation, etc. KEGG pathway analysis was mainly involved in complement and coagulation cascades, ECM-receptor. Hub genes screened by Cytoscape consist ofCD44, ACTB, FN1, ITGB1, PLG, CASP3, ALB, HSP90AA1, EGF, GAPDH. Lastly, qRT-PCR results showed statistic significance (P < 0.05) in ALB, CD44 and EGF before and after treatment, and EGF immunostaining was localized in neuron of cortex.

Conclusion

husc transplantation showed a positive effect in improving neural function of CIR rats, and underlying mechanism is involved in CD44, ALB, and EGF network.

Isolation and usage of exosomes in central nervous system diseases

BACKGROUND

Exosomes are vesicles secreted by all types of mammalian cells. They are characterized by a double-layered lipid membrane structure. They serve as carriers for a plethora of signal molecules, including DNA, RNA, proteins, and lipids. Their unique capability of effortlessly crossing the blood-brain barrier underscores their critical role in the progression of various neurological disorders. This includes, but is not limited to, diseases such as Alzheimer's, Parkinson's, and ischemic stroke. Establishing stable and mature methods for isolating exosomes is a prerequisite for the study of exosomes and their biomedical significance. The extraction technologies of exosomes include differential centrifugation, density gradient centrifugation, size exclusion chromatography, ultrafiltration, polymer coprecipitation, immunoaffinity capture, microfluidic, and so forth. Each extraction technology has its own advantages and disadvantages, and the extraction standards of exosomes have not been unified internationally.

AIMS

This review aimed to showcase the recent advancements in exosome isolation techniques and thoroughly compare the advantages and disadvantages of different methods. Furthermore, the significant research progress made in using exosomes for diagnosing and treating central nervous system (CNS) diseases has been emphasized.

CONCLUSION

The varying isolation methods result in differences in the concentration, purity, and size of exosomes. The efficient separation of exosomes facilitates their widespread application, particularly in the diagnosis and treatment of CNS diseases.

Alginate microspheres encapsulating hox transcript antisense RNA siRNA regulate the Hedgehog-Gli1 pathway to alleviate epidermal growth factor receptor tyrosine kinase inhibitors resistance

The long non-coding RNA HOTAIR and the Hedgehog-Gli1 signaling pathway are closely associated with tumor occurrence and drug resistance in various cancers. However, their specific roles in the development of EGFR-TKIs resistance in non-small cell carcinoma remain unclear. To address the issue of EGFR-TKIs resistance, this study utilized the electrospray method to prepare sodium alginate microspheres encapsulating HOTAIR siRNA (SA/HOTAIR siRNA) and investigated its effects on RNA interference (RNAi) in the gefitinib-resistant cell line PC9/GR. Furthermore, the study explored whether HOTAIR could modulate EGFR-TKIs resistance through the Hedgehog-GLi1 signaling pathway. The experimental results showed that sodium alginate (SA) microspheres demonstrated excellent biocompatibility with high encapsulation efficiency and drug-loading capacity, effectively enhancing the silencing efficiency of siRNA. HOTAIR siRNA significantly inhibited the proliferation, migration, and invasion abilities of PC9/GR cells while promoting apoptosis. Additionally, HOTAIR siRNA effectively suppressed tumor growth and downregulated the Hedgehog-GLi1 pathway and anti-apoptotic proteins, which were confirmed in animal experiments. Moreover, SA/HOTAIR siRNA exhibited superior inhibition of cellular and tumor functions compared to using HOTAIR siRNA alone. Clinical research findings indicated that monitoring the expression level of HOTAIR in the serum and urine samples of NSCLC patients before and after receiving EGFR-TKIs treatment can predict the efficacy of EGFR-TKIs to a certain extent. This study provided evidence that HOTAIR siRNA effectively mitigated the development of acquired resistance to EGFR-TKIs by inhibiting the Hedgehog-GLi1 pathway. Furthermore, it introduced a reliable and long-lasting drug delivery system for combating acquired resistance to EGFR-TKIs.

Human umbilical cord mesenchymal stem cell-derived exosomes attenuate neuroinflammation and oxidative stress through the NRF2/NF-κB/NLRP3 pathway

AIMS

We investigated whether human umbilical cord mesenchymal stem cell (hUC-MSC)-derived exosomes bear therapeutic potential against lipopolysaccharide (LPS)-induced neuroinflammation.

METHODS

Exosomes were isolated from hUC-MSC supernatant by ultra-high-speed centrifugation and characterized by transmission electron microscopy and western blotting. Inflammatory responses were induced by LPS in BV-2 cells, primary microglial cultures, and C57BL/6J mice. H2 O2 was also used to induce inflammation and oxidative stress in BV-2 cells. The effects of hUC-MSC-derived exosomes on inflammatory cytokine expression, oxidative stress, and microglia polarization were studied by immunofluorescence and western blotting.

RESULTS

Treatment with hUC-MSC-derived exosomes significantly decreased the LPS- or H2 O2 -induced oxidative stress and expression of pro-inflammatory cytokines (IL-6 and TNF-α) in vitro, while promoting an anti-inflammatory (classical M2) phenotype in an LPS-treated mouse model. Mechanistically, the exosomes increased the NRF2 levels and inhibited the LPS-induced NF-κB p65 phosphorylation and NLRP3 inflammasome activation. In contrast, the reactive oxygen species scavenger NAC and NF-κB inhibitor BAY 11-7082 also inhibited the LPS-induced NLRP3 inflammasome activation and switched to the classical M2 phenotype. Treatment with the NRF2 inhibitor ML385 abolished the anti-inflammatory and anti-oxidative effects of the exosomes.

CONCLUSION

hUC-MSC-derived exosomes ameliorated LPS/H2 O2 -induced neuroinflammation and oxidative stress by inhibiting the microglial NRF2/NF-κB/NLRP3 signaling pathway.

Understanding exosomes: Part 3-therapeutic + diagnostic potential in dentistry

Exosomes are the smallest subset of extracellular signaling vesicles secreted by most cells with the ability to communicate with other tissues and cell types over long distances. Their use in regenerative medicine has gained tremendous momentum recently due to their ability to be utilized as therapeutic options for a wide array of various diseases. Over 5000 publications are currently being published on this topic yearly, many of which in the dental space. This extensive review article is the first scoping review aimed at summarizing all therapeutic uses of exosomes in regenerative dentistry. A total of 944 articles were identified as using exosomes in the dental field for either their regenerative/therapeutic potential or for diagnostic purposes derived from the oral cavity. In total, 113 research articles were selected for their regenerative potential (102 in vitro, 60 in vivo, 50 studies included both). Therapeutic exosomes were most commonly derived from dental pulps, periodontal ligament cells, gingival fibroblasts, stem cells from exfoliated deciduous teeth, and the apical papilla which have all been shown to facilitate the regenerative potential of a number of tissues including bone, cementum, the periodontal ligament, nerves, aid in orthodontic tooth movement, and relieve temporomandibular joint disorders, among others. Results demonstrate that the use of exosomes led to positive outcomes in 100% of studies. In the bone field, exosomes were found to perform equally as well or better than rhBMP2 while significantly reducing inflammation. Periodontitis animal models were treated with simple gingival injections of exosomes and benefits were even observed when the exosomes were administered intravenously. Exosomes are much more stable than growth factors and were shown to be far more resistant against degradation by periodontal pathogens found routinely in a periodontitis environment. Comparative studies in the field of periodontal regeneration found better outcomes for exosomes even when compared to their native parent stem cells. In total 47 diagnostic studies revealed a role for salivary/crevicular fluid exosomes for the diagnosis of birth defects, cardiovascular disease, diabetes, gingival recession detection, gingivitis, irritable bowel syndrome, neurodegenerative disease, oral lichen planus, oral squamous cell carcinoma, oropharyngeal cancer detection, orthodontic root resorption, pancreatic cancer, periodontitis, peri-implantitis, Sjögren syndrome, and various systemic diseases. Hence, we characterize the exosomes as possessing "remarkable" potential, serving as a valuable tool for clinicians with significant advantages.

Engineered exosomes derived from stem cells: a new brain-targeted strategy

INTRODUCTION

Using engineered exosomes produced from stem cells is an experimental therapeutic approach for treating brain diseases. According to reports, preclinical research has demonstrated notable neurogenesis and angiogenesis effects using modified stem cell-derived exosomes. These biological nanoparticles have a variety of anti-apoptotic, anti-inflammatory, and antioxidant properties that make them very promising for treating nervous system disorders.

AREAS COVERED

This review examines different ways to enhance the delivery of modified stem cell-derived exosomes, how they infiltrate the blood-brain barrier (BBB), and how they facilitate their access to the brain. We would also like to determine whether these nanoparticles have the most significant transmission rates through BBB when targeting brain lesions.

EXPERT OPINION

Using engineered stem cell-derived exosomes for treating brain disorders has generated considerable attention toward clinical research and application. However, stem cell-derived exosomes lack consistency, and their mechanisms of action are uncertain. Therefore, upcoming research needs to prioritize examining the underlying mechanisms and strategies via which these nanoparticles combat neurological disorders.

Macrophages-derived exo-miR-4449 induced by Cryptococcus affects HUVEC permeability and promotes pyroptosis in BEAS-2B via the HIC1 pathway

Macrophages have recently been discovered to assume a significant role in the progression of cryptococcosis. However, the potential involvement of macrophage-derived exosomes in the pathogenesis of cryptococcosis remains uncertain. In this study, we investigated the changes of microRNAs in macrophage exosomes (exo-miRNAs) in cryptococcal infections and the role of markedly altered exo-miRNAs in the modulation of Human Umbilical Vein Endothelial Cells (HUVEC) permeability and ROS accumulation and pyroptosis in Human Bronchial Epithelioid Cells (BEAS-2B). Techniques such as microarray analysis and real-time quantitative PCR were used to detect different exo-miRNAs and to screen for the most highly expressed exo-miRNAs. Then its mimics were transfected into HUVEC to study its effect on the monolayer permeability of HUVEC. Finally, the relationship between this exo-miRNAs and the ROS accumulation and pyroptosis was verified by bioinformatics analysis. The results showed that five exo-miRNAs were overexpressed and two exo-miRNAs were reduced, among which, exo-miR-4449 was expressed at the highest level. Exo-miR-4449 could be internalized by HUVEC and enhanced its monolayer permeability. Moreover, exo-miR-4449 was found to promote ROS accumulation and pyroptosis in BEAS-2B through HIC1 pathway. Thus, exo-miR-4449 plays an important role in the pathogenesis of cryptococcosis and holds promise as a significant biomarker for treatment.

Advances in oral mesenchymal stem cell-derived extracellular vesicles in health and disease

Extracellular vesicles (EVs) are nano-size vesicles secreted naturally by all cells into the extracellular space and have been recognized as important cell-cell mediators in multicellular organisms. EVs contain nucleic acids, proteins, lipids, and other cellular components, regulating many basic biological processes and playing an important role in regenerative medicine and diseases. EVs can be traced to their cells of origin and exhibit a similar function. Moreover, EVs demonstrate low immunogenicity, good biocompatibility, and fewer side effects, compared to their parent cells. Mesenchymal stem cells (MSCs) are one of the most important resource cells for EVs, with a great capacity for self-renewal and multipotent differentiation, and play an essential role in stem cell therapy. The mechanism of MSC therapy was thought to be attributed to the differentiation of MSCs after targeted migration, as previously noted. However, emerging evidence shows the previously unknown role of MSC-derived paracrine factors in stem cell therapy. Especially EVs derived from oral tissue MSCs (OMSC-EVs), show more advantages than those of all other MSCs in tissue repair and regeneration, due to their lower invasiveness and easier accessibility for sample collection. Here, we systematically review the biogenesis and biological characteristics of OMSC-EVs, as well as the role of OMSC-EVs in intercellular communication. Furthermore, we discuss the potential therapeutic roles of OMSC-EVs in oral and systemic diseases. We highlight the current challenges and future directions of OMSC-EVs to focus more attention on clinical translation. We aim to provide valuable insights for the explorative clinical application of OMSC-EVs.

Inhibitory effects of the nanoscale lysate derived from xenogenic dental pulp stem cells in lung cancer models

BACKGROUND

Lung cancer is a highly prevalent malignancy and has the highest mortality rate among all tumors due to lymph node metastasis. Bone marrow and umbilical cord-derived mesenchymal stem cells (MSCs) have demonstrated tumor-suppressive effects on lung cancer. This study investigated the effects of DPSC lysate on proliferation, apoptosis, migration and invasion of cancer cells were studied in vivo and in vitro.

METHODS

The proliferation, apoptosis, and migration/metastasis were evaluated by cell counting kit-8 assay, Annexin-V and propidium iodide staining, and the transwell assay, respectively. The expression levels of apoptosis-, cell cycle-, migration-, and adhesion-related mRNA and proteins were measured by qRT-PCR and western blot. The level and mRNA expression of tumor markers carcino embryonic antigen (CEA), neuron-specific enolase (NSE), and squamous cell carcinoma (SCC) were measured by Enzyme-linked immunosorbent assay (ELISA) and qRT-PCR. Finally, a tumor-bearing mouse model was constructed to observe the tumor-suppressive effect of DPSC lysate after intraperitoneal injection.

RESULTS

DPSC lysate decreased the viability of A549 cells and induced apoptosis in lung cancer cells. Western blot confirmed that levels of Caspase-3, Bax, and Bad were increased, and Bcl-2 protein levels were decreased in A549 cells treated with DPSC lysate. In addition, DPSC lysate inhibited the migration and invasion of A549 cells; downregulated key genes of the cell cycle, migration, and adhesion; and significantly suppressed tumor markers. Xenograft results showed that DPSC lysate inhibited tumor growth and reduced tumor weight.

CONCLUSIONS

DPSC lysate inhibited proliferation, invasion, and metastasis; promoted apoptosis in lung cancer cells; and suppressed tumor growth- potentially providing a cell-based alternative therapy for lung cancer treatment.

Exosomes derived from odontogenic stem cells: Its role in the dentin-pulp complex

Odontogenic stem cells originate from cranial neural crest cells and offer unique advantages in the regeneration of dentin-pulp complex. There is increasing evidence that stem cells exert their biological functions mainly through exosome-based paracrine effects. Exosomes contain DNA, RNA, proteins, metabolites, etc., which can play a role in intercellular communication and have similar therapeutic potential to stem cells. In addition, compared with stem cells, exosomes also have the advantages of good biocompatibility, high drug carrying capacity, easy to obtain, and few side effects. Odontogenic stem cell-derived exosomes mainly affect the regeneration of the dentin-pulp complex by regulating processes such as dentintogenesis, angiogenesis, neuroprotection and immunomodulation. This review aimed to describe "cell-free therapies" based on odontogenic stem cell-derived exosomes, which aim to regenerate the dentin-pulp complex.

Exosomes derived from bone marrow mesenchymal stem cells regulate pyroptosis via the miR-143-3p/myeloid differentiation factor 88 axis to ameliorate intestinal ischemia-reperfusion injury

Intestinal ischemia-reperfusion (I/R) injury is a condition in which tissue injury is aggravated after ischemia due to recovery of blood supply. Bone marrow mesenchymal stem cell-derived exosome (BMSC-exo) showed a protective effect on I/R injury. This study aimed to investigate the possible mechanisms by which BMSC-exos ameliorate intestinal I/R injury. We isolated mouse BMSC-exos by super-centrifugation and found that they effectively increased cell viability in a cell model, alleviated intestinal barrier injury in a mouse model, and downregulated the expression of inflammatory cytokines and pyroptosis-related proteins, suggesting that BMSC-exos may alleviate intestinal I/R injury in vitro and in vivo by regulating pyroptosis. We identified miR-143-3p as a differentially expressed miRNA by microarray sequencing. Bioinformatic analysis predicted a binding site between miR-143-3p and myeloid differentiation factor 88 (MyD88); a dual-luciferase reporter assay confirmed that miR-143-3p could directly regulate the expression of MyD88. Our findings suggest that miR-143-3p regulates pyroptosis by regulating NOD-like receptor thermal protein domain associated protein 3 (NLRP3) through the toll-like receptor (TLR)-4/MyD88/nuclear factor kappa-B (NF-кB) pathway. This study describes a potential strategy for the treatment of intestinal I/R injury using BMSC-exos that act by regulating pyroptosis through the miR-143-3p mediated TLR4/MyD88/NF-кB pathway.

Anti-inflammatory effect of dental pulp stem cells

Dental pulp stem cells (DPSCs) have received a lot of attention as a regenerative medicine tool with strong immunomodulatory capabilities. The excessive inflammatory response involves a variety of immune cells, cytokines, and has a considerable impact on tissue regeneration. The use of DPSCs for controlling inflammation for the purpose of treating inflammation-related diseases and autoimmune disorders such as supraspinal nerve inflammation, inflammation of the pulmonary airways, systemic lupus erythematosus, and diabetes mellitus is likely to be safer and more regenerative than traditional medicines. The mechanism of the anti-inflammatory and immunomodulatory effects of DPSCs is relatively complex, and it may be that they themselves or some of the substances they secrete regulate a variety of immune cells through inflammatory immune-related signaling pathways. Most of the current studies are still at the laboratory cellular level and animal model level, and it is believed that through the efforts of more researchers, DPSCs/SHED are expected to be transformed into excellent drugs for the clinical treatment of related diseases.

Potential of dental pulp stem cells and their products in promoting peripheral nerve regeneration and their future applications

Peripheral nerve injury (PNI) seriously affects people's quality of life. Stem cell therapy is considered a promising new option for the clinical treatment of PNI. Dental stem cells, particularly dental pulp stem cells (DPSCs), are adult pluripotent stem cells derived from the neuroectoderm. DPSCs have significant potential in the field of neural tissue engineering due to their numerous advantages, such as easy isolation, multidifferentiation potential, low immunogenicity, and low transplant rejection rate. DPSCs are extensively used in tissue engineering and regenerative medicine, including for the treatment of sciatic nerve injury, facial nerve injury, spinal cord injury, and other neurodegenerative diseases. This article reviews research related to DPSCs and their advantages in treating PNI, aiming to summarize the therapeutic potential of DPSCs for PNI and the underlying mechanisms and providing valuable guidance and a foundation for future research.

Research progress of odontogenic extracellular vesicles in regeneration of dental pulp

It is well understood that maintaining viable pulp is critical for tooth retention. This review focused on cell-free therapy based on extracellular vesicles (EVs), a novel minimally invasive treatment strategy for endodontic restoration. This study was conducted by searching mainstream electronic databases such as Web of Science and PubMed for relevant studies on the therapeutic role of odontogenic EVs in pulp healing published in the last five years. We selected 89 relevant articles and discovered that dental stem cells (DSCs) derived EVs (DSC-EVs) have become a research hotspot in oral regenerative medicine, with significant advantages over cell transplantation in terms of low immunogenicity, ease of isolation, preservation, and management. Here, we introduce in detail the therapeutic effects of DSC-EVs for pulp restoration from three perspectives: excellent odontogenic properties, clinical applications, and possible molecular mechanisms. This article contributes a new viewpoint to the field of regenerative endodontics.

A robust panel based on genomic methylation sites for recurrence-free survival in early hepatocellular carcinoma

Purpose

Altered gene methylation precedes altered gene expression and the onset of disease. This study aimed to develop a potential model for predicting recurrence of early to mid-stage hepatocellular carcinoma (HCC) using methylation loci.

Methods

We used data from early to mid-stage HCC patients (TNM I-II) in the TCGA-LIHC dataset and lasso-cox regression model to identify an 18-DNA methylation site panel from which to calculate the riskScore of patients. The correlation of high/low riskScore with recurrence-free survival (RFS) and immune microenvironment in HCC patients was analyzed by bioinformatics. It was also validated in the GSE56588 dataset and the final dynamic nomogram was constructed.

Results

The results showed that riskScore was significantly correlated with RFS in HCC patients. The differential mutated genes between the two groups of HCC patients with high/low riskScore were mainly enriched in the TP53 signaling pathway. The immune microenvironment was better in HCC patients in the low-riskScore group compared to the high-riskScore group. This was validated in the GSE56588 dataset. Based on the subgroup stratification analysis of the relationship between high/low riskScore and RFS, as well as univariate and multivariate cox analyses, the riskScore was found to be independent of clinical indicators. We found that riskScore, vascular invasion and cirrhosis status could effectively differentiate RFS in HCC patients, and we also constructed prediction model based on these three factors. The model we constructed were validated in the TCGA-LIHC database and a web calculator was built for clinical use.

Conclusion

The methylation riskScore is a predictor of RFS independent of clinical factors and can be used as a marker to predict recurrence in HCC patients.

Knockdown of protein interacting with C α kinase 1 aggravates sepsis-induced acute liver injury by regulating the TLR4/NF-κB pathway

Acute liver injury (ALI) may manifest at any phase of sepsis, yet an explicit therapeutic approach remains elusive. In this study, LPS and cecum ligation and puncture (CLP) were utilized to establish an inflammatory cell model and a murine model of sepsis-induced liver injury, respectively, aiming to explore the potential protective effect of protein interacting with C α kinase 1 (PICK1) on sepsis-induced ALI and its underlying mechanisms. In both the cell supernatant and the murine whole blood, the concentrations of inflammatory factors were quantified by ELISA, while the protein and mRNA expressions of PICK1, cleaved-PARP-1, caspase1, TLR4, IκBα, and NF-κB were assessed via western blot and qRT-PCR. The outcomes revealed that the knockdown of PICK1 increased the levels of inflammatory factors and apoptosis, alongside activation of TLR4/NF-κB signaling pathway-related factors in both in vivo and in vitro models. Moreover, the murine liver samples were subjected to Hematoxylin-Eosin (HE) staining for assessment of histopathological morphology. The HE staining and liver injury scoring results manifested a markedly exacerbated hepatic damage in PICK1 knockout mice as compared to WT mice following CLP. Furthermore, the liver macrophages were isolated from murine livers, and the expression and activity of the factors associated with the TLR4/NF-κB signaling pathway were verified through RT-qPCR and western blot, and EMSA assay demonstrated an augmented NF-κB activity subsequent to PICK1 knockout. Finally, the expression and localization of PICK1 in macrophages were further scrutinized via immunofluorescence, and the interaction between PICK1 and TLR4 was identified through co-immunoprecipitation. In conclusion, the knockdown of PICK1 appeared to modulate inflammatory factors by activating the TLR4/NF-κB signaling pathway, thereby exacerbating hepatic damage induced by sepsis.

Immunomodulatory Mechanism and Potential Application of Dental Pulp-Derived Stem Cells in Immune-Mediated Diseases

Dental pulp stem cells (DPSCs) are mesenchymal stem cells (MSCs) derived from dental pulp tissue, which have high self-renewal ability and multi-lineage differentiation potential. With the discovery of the immunoregulatory ability of stem cells, DPSCs have attracted much attention because they have similar or even better immunomodulatory effects than MSCs from other sources. DPSCs and their exosomes can exert an immunomodulatory ability by acting on target immune cells to regulate cytokines. DPSCs can also migrate to the lesion site to differentiate into target cells to repair the injured tissue, and play an important role in tissue regeneration. The aim of this review is to summarize the molecular mechanism and target cells of the immunomodulatory effects of DPSCs, and the latest advances in preclinical research in the treatment of various immune-mediated diseases, providing new reflections for their clinical application. DPSCs may be a promising source of stem cells for the treatment of immune-mediated diseases.

Therapeutic potential of stem cell extracellular vesicles for ischemic stroke in preclinical rodent models: a meta-analysis

BACKGROUND

Extracellular vesicles derived from stem cells (SC-EVs) have been proposed as a novel therapy for ischemic stroke. However, their effects remain incompletely understood. Therefore, we conducted this meta-analysis to systematically review the efficacy of SC-EVs on ischemic stroke in preclinical rodent models.

METHODS

Using PubMed, EMBASE, and the Web of Science, we searched through studies published up to August 2021 that investigated the treatment effects of SC-EVs in a rodent ischemic stroke model. Infarct volume was the primary outcome. Neurological severity scores (mNSS) were the secondary outcome. The standard mean difference (SMD) and the confidence interval (CI) were calculated using a random-effects model. R and Stata 15.1 were used to conduct the meta-analysis.

RESULTS

Twenty-one studies published from 2015 to 2021 met the inclusion criteria. We also found that SCs-EVs reduced infarct volume by an SMD of - 2.05 (95% CI - 2.70, - 1.40; P < 0.001). Meanwhile, our results revealed an overall positive effect of SCs-derived EVs on the mNSS with an SMD of - 1.42 (95% CI - 1.75, - 1.08; P < 0.001). Significant heterogeneity among studies was observed. Further stratified and sensitivity analyses did not identify the source of heterogeneity.

CONCLUSION

The present meta-analysis confirmed that SC-EV therapy could improve neuron function and reduce infarct volume in a preclinical rodent ischemic stroke model, providing helpful clues for human clinical trials on SC-EVs.

The Emerging Biological Functions of Exosomes from Dental Tissue-Derived Mesenchymal Stem Cells

Exosomes are one kind of small-cell extracellular membranous vesicles that can regulate intercellular communication and give rise to mediating the biological behaviors of cells, involving in tissue formation, repair, the modulation of inflammation, and nerve regeneration. The abundant kinds of cells can secret exosomes, among them, mesenchymal stem cells (MSCs) are very perfect cells for mass production of exosomes. Dental tissue-derived mesenchymal stem cells (DT-MSCs), including dental pulp stem cells, stem cells from exfoliated deciduous teeth, stem cells from apical papilla, stem cells from human periodontal ligament (PDLSCs), gingiva-derived mesenchymal stem cells, dental follicle stem cells, tooth germ stem cells, and alveolar bone-derived mesenchymal stem cells, are now known as a potent tool in the area of cell regeneration and therapy, more importantly, DT-MSCs can also release numerous types of exosomes, participating in the biological functions of cells. Hence, we briefly depict the characteristics of exosomes, give a detailed description of the biological functions and clinical application in some respects of exosomes from DT-MSCs through systematically reviewing the latest evidence, and provide a rationale for their use as tools for potential application in tissue engineering.

Immunomodulatory properties of mesenchymal stem cells/dental stem cells and their therapeutic applications

Mesenchymal stem/stromal cells (MSCs) are widely distributed in the body and play essential roles in tissue regeneration and homeostasis. MSCs can be isolated from discarded tissues, expanded in vitro and used as therapeutics for autoimmune diseases and other chronic disorders. MSCs promote tissue regeneration and homeostasis by primarily acting on immune cells. At least six different types of MSCs have been isolated from postnatal dental tissues and have remarkable immunomodulatory properties. Dental stem cells (DSCs) have been demonstrated to have therapeutic effects on several systemic inflammatory diseases. Conversely, MSCs derived from nondental tissues such as the umbilical cord exhibit great benefits in the management of periodontitis in preclinical studies. Here, we discuss the main therapeutic uses of MSCs/DSCs, their mechanisms, extrinsic inflammatory cues and the intrinsic metabolic circuitries that govern the immunomodulatory functions of MSCs/DSCs. Increased understanding of the mechanisms underpinning the immunomodulatory functions of MSCs/DSCs is expected to aid in the development of more potent and precise MSC/DSC-based therapeutics.

Clinical trials using dental stem cells: 2022 update

For nearly 20 years, dental stem cells (DSCs) have been successfully isolated from mature/immature teeth and surrounding tissue, including dental pulp of permanent teeth and exfoliated deciduous teeth, periodontal ligaments, dental follicles, and gingival and apical papilla. They have several properties (such as self-renewal, multidirectional differentiation, and immunomodulation) and exhibit enormous potential for clinical applications. To date, many clinical articles and clinical trials using DSCs have reported the treatment of pulpitis, periapical lesions, periodontitis, cleft lip and palate, acute ischemic stroke, and so on, and DSC-based therapies obtained satisfactory effects in most clinical trials. In these studies, no adverse events were reported, which suggested the safety of DSC-based therapy. In this review, we outline the characteristics of DSCs and summarize clinical trials and their safety as DSC-based therapies. Meanwhile, we also present the current limitations and perspectives of DSC-based therapy (such as harvesting DSCs from inflamed tissue, applying DSC-conditioned medium/DSC-derived extracellular vesicles, and expanding-free strategies) to provide a theoretical basis for their clinical applications.

Analysis of the Research Hotspot of Exosomes in Cardiovascular Disease: A Bibliometric-based Literature Review

OBJECTIVE

To investigate the current status and development trend of research on exosomes in cardiovascular disease (CVD) using bibliometric analysis and to elucidate trending research topics.

METHODS

Research articles on exosomes in CVD published up to April 2022 were retrieved from the Web of Science database. Data were organized using Microsoft Office Excel 2019. CiteSpace 6.1 and VOSviewer 1.6.18 were used for bibliometric analysis and result visualization.

RESULTS

Overall, 256 original research publications containing 190 fundamental research publications and 66 clinical research publications were included. "Extracellular vesicle" was the most frequent research keyword, followed by "microrna," "apoptosis," and "angiogenesis." Most publications were from China (187, 73.05%), followed by the United States (57, 22.27%), the United Kingdom (7, 2.73%), and Japan (7, 2.73%). A systematic review of the publications revealed that myocardial infarction and stroke were the most popular topics and that exosomes and their contents, such as microRNAs (miRNAs), play positive roles in neuroprotection, inhibition of autophagy and apoptosis, promotion of angiogenesis, and protection of cardiomyocytes.

CONCLUSION

Research on exosomes in CVD has attracted considerable attention, with China having the most published studies. Fundamental research has focused on CVD pathogenesis; exosomes regulate the progression of CVD through biological processes, such as the inflammatory response, autophagy, and apoptosis. Clinical research has focused on biomarkers for CVD; studies on using miRNAs in exosomes as disease markers for diagnosis could become a future trend.

Dental Pulp Stem Cells Ameliorate Elastase-Induced Pulmonary Emphysema by Regulating Inflammation and Oxidative Stress

Background

Dental pulp stem cells (DPSCs) are considered excellent candidates for stem cell-based tissue regeneration. In this study, we aimed to evaluate the therapeutic effect of DPSCs in a mouse chronic obstructive pulmonary disease (COPD) model and to explore whether DPSCs reduce lung inflammation and oxidative stress by regulating the nuclear factor erythroid-2 related factor-2 (Nrf2) signaling pathway.

Methods

DPSCs were isolated from dental pulp tissue by the tissue block method. Emphysema of C57BL/6 mice was induced by endotracheal administration of porcine pancreatic elastase (PPE). Then, the DPSCs were injected into the lungs through the trachea, and after 3 weeks of stem cell treatment, various efficacy tests were performed. The AniRes2005 animal lung function analytic system was used to detect lung function. Hematoxylin-eosin staining (H&E) and Victoria blue staining was used to assess emphysema severity. The animal tissues were detected by Western blot, RT‒qPCR, ELISA and oxidative stress related detection.

Results

In experimental COPD models, DPSCs transplantation improved lung function, body weight, and emphysema-like changes better than bone marrow mesenchyml stem cells (BM-MSCs). Compared with the COPD group, the levels of IL-1β, TNF-α and IL-6 in lung tissue and bronchoalveolar lavage fluid (BALF) were decreased after transplantation of DPSCs. DPSCs may be associated with lower malondialdehyde (MDA) levels, and higher catalase (CAT) and glutathione (GSH) levels. Western blot results showed that the expression of Nrf2 and its downstream factors increased after transplantation of DPSCs.

Conclusion

The current study showed that DPSCs had good performance in the treatment of a mouse COPD model and could be a promising option for stem cell therapy. DPSCs may play antioxidant and anti-inflammatory roles in COPD by activating the Nrf2 signaling pathway.

Exosomes in pathogenesis, diagnosis, and therapy of ischemic stroke

Ischemic stroke is one of the major contributors to death and disability worldwide. Thus, there is an urgent need to develop early brain tissue perfusion therapies following acute stroke and to enhance functional recovery in stroke survivors. The morbidity, therapy, and recovery processes are highly orchestrated interactions involving the brain with other tissues. Exosomes are natural and ideal mediators of intercellular information transfer and recognized as biomarkers for disease diagnosis and prognosis. Changes in exosome contents express throughout the physiological process. Accumulating evidence demonstrates the use of exosomes in exploring unknown cellular and molecular mechanisms of intercellular communication and organ homeostasis and indicates their potential role in ischemic stroke. Inspired by the unique properties of exosomes, this review focuses on the communication, diagnosis, and therapeutic role of various derived exosomes, and their development and challenges for the treatment of cerebral ischemic stroke.

Effects and Mechanisms of Exosomes from Different Sources in Cerebral Ischemia

Cerebral ischemia refers to the symptom of insufficient blood supply to the brain. Cells of many different origins participate in the process of repairing damage after cerebral ischemia occurs, in which exosomes secreted by the cells play important roles. For their characteristics, such as small molecular weight, low immunogenicity, and the easy penetration of the blood-brain barrier (BBB), exosomes can mediate cell-to-cell communication under pathophysiological conditions. In cerebral ischemia, exosomes can reduce neuronal damage and improve the brain microenvironment by regulating inflammation, mediating pyroptosis, promoting axonal growth, and stimulating vascular remodeling. Therefore, exosomes have an excellent application prospect for the treatment of cerebral ischemia. This article reviews the roles and mechanisms of exosomes from different sources in cerebral ischemia and provides new ideas for the prevention and treatment of cerebral ischemia.

Characteristics of culture-condition stimulated exosomes or their loaded hydrogels in comparison with other extracellular vesicles or MSC lysates

Recently, it has become popular to study the use of extracellular vesicles (EVs) secreted by stem cells to repair damaged tissues or lost cells. Various cell types and physiological fluids release EVs, and they play an important role in cell-to-cell communication. Moreover, EVs have been implicated in important processes, such as immune responses, homeostasis maintenance, coagulation, inflammation, cancer progression, angiogenesis, and antigen presentation. Thus, EVs participate in both physiological and pathological progression. The main classes of EVs include exosomes, microvesicles (MVs), and apoptotic bodies (ApoBDs). Exosomes, which carry a mass of signal molecules such as RNA, DNA, proteins, and lipids, are the most important of these EVs subsets. Currently, exosomes are generating substantial interest in the scientific community. Exosomes loaded hydrogels or under different cultural environments exhibit different properties and functions. Therefore, the exosomes obtained from different sources and conditions are worth reviewing. More importantly, no review article has compared the different EVs, such as exosomes, MVs, ApoBDs, and mesenchymal stem cell (MSC) lysates, which are special soluble substances. The differentiation between EVs and MSC lysates is a logical approach. Accordingly, this review provides an update on the latest progress in studying the roles of culture-condition stimulated exosomes or their loaded hydrogels and the differentiation between exosomes, MVs, ApoBDs, and MSC lysates. Published studies were retrieved from the PubMed® database for review.

Exosomes as Neurological Nanosized Machines

In the past few decades, nanomedicine research has advanced dramatically. In spite of this, traditional nanomedicine faces major obstacles, such as blood-brain barriers, low concentrations at target sites, and rapid removal from the body. Exosomes as natural extracellular vesicles contain special bioactive molecules for cell-to-cell communications and nervous tissue function, which could overcome the challenges of nanoparticles. Most recently, microRNAs, long noncoding RNA, and circulating RNA of exosomes have been appealing because of their critical effect on the molecular pathway of target cells. In this review, we have summarized the important role of exosomes of noncoding RNAs in the occurrence of brain diseases.

Dental pulp stem cell transplantation facilitates neuronal neuroprotection following cerebral ischemic stroke

OBJECTIVES

This study aimed to identify and evaluate the intracranial transplantation of dental pulp stem cells (DPSCs) as a possible ischemic stroke therapy that mitigates neuronal death/apoptosis.

MATERIALS AND METHODS

DPSCs were isolated from the impacted third molars of healthy volunteers and then intracranially injected at 24 h post-ischemic stroke to Sprague Dawley rats that had been subjected to 2 h of middle cerebral artery occlusion. Neurological functional deficits were assessed using the modified neurological severity score (mNSS), and cerebral edema was quantified using brain water content. Neuronal death/apoptosis was indicated by TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, NeuN immunofluorescence and immunohistochemistry, and Western blot analysis of the protein expression of anti-apoptotic indicator of Bcl-2 and apoptotic indicators of Bax and caspase 3.

RESULTS

DPSC transplantation could ameliorate neurological dysfunction and brain edema, reduce infarct volume, decrease the percentage of TUNEL-positive nuclei, increase the number and percentage of NeuN-positive cells in ischemic penumbra, increase the ratio of Bcl-2 and Bax and down-regulate the production of caspase 3 in the cortical infarct zone.

CONCLUSIONS

DPSC therapy via intracranial injection exerted remarkably neuroprotection mainly by inhibiting neuronal death/apoptosis.