Stem Cell Research & Therapy最新文献

Understanding the complexities of the human brain development remains one of the most formidable challenges in neuroscience, constrained by the limitations of traditional models and the inaccessibility of brain tissue. The advent of cerebral organoids has provided a transformative in vitro model that closely mimics the early stages of brain development, including the spatiotemporal organization and cellular heterogeneity. Derived from pluripotent stem cells, these self-assembling three-dimensional structures address critical limitations of earlier systems, including species-specific differences in animal studies and the structural constraints of conventional cell models. Over the past decade, cerebral organoids have enabled significant advances in studying neural development, neurogenesis, modeling neuroconnectivity, and investigating neuroregeneration. Meanwhile, high-throughput spatial multi-omics technologies have emerged for decoding molecular and cellular dynamics with spatial precision. These techniques retain the architectural context of biological samples while integrating diverse layers of omic information, providing unprecedented insights into tissue organization and interactions. By addressing the complexity of brain organization and facilitating actionable insights into neurodevelopmental diseases, this integration facilitates high-throughput drug screening, identifies disease-specific targets, and offers a path to novel therapeutic strategies and regenerative solution for future stem cell therapies for pediatric neurodevelopmental diseases.

Background: Effective treatments for cerebral palsy caused by Hypoxic-ischemic encephalopathy are urgently needed. Current therapies primarily include prevention or acute intervention, leaving a major gap in the options for reversing established neurologic damage. Because of their ease of collection and unique trophic factor profile, stem cells from human exfoliated deciduous teeth (SHED) are promising candidates for cell-based therapy targeting neurological disorders. In this study, we examined the therapeutic potential of SHED in a rat model of cerebral palsy, focusing on neurogenic and functional recovery.

Methods: Hypoxic-ischemic encephalopathy was induced in neonatal rats using the Rice-Vannucci method. Rats with motor impairments received intravenous SHED injections, whereas the control group received a vehicle solution. Behavioral tests assessed motor coordination and cognitive performance. Proteomic analyses and immunohistochemistry were performed to examine the underlying mechanisms. The migration and biodistribution of SHED were tracked using quantum dot-labeled SHED with in vivo imaging. Neural stem cells were cocultured with SHED to evaluate neurogenesis, followed by RNA sequencing and the analysis of trophic factors in the conditioned media.

Results: SHED treatment significantly ameliorated motor coordination, memory, and learning. Proteomic analysis revealed increased expression of proteins associated with neurogenesis in the SHED group. Histopathologic evaluations revealed enhanced neurogenesis in the hippocampal dentate gyrus and subventricular zone 2 weeks posttreatment, with increased NeuN-positive cells in the hippocampus and cortex at ten weeks. In vivo imaging revealed the migration of quantum dot-labeled SHED to the brain. Neural stem cells co-cultured with SHED in vitro exhibited higher proliferation rates. The SHED-conditioned medium contained increased levels of hepatocyte growth factor (HGF), and HGF-neutralizing antibodies suppressed the enhanced cell proliferation. RNA sequencing revealed significant alterations in genes associated with the PI3K-Akt signaling pathway.

Conclusions: SHED treatment ameliorated motor, memory, and learning impairment in a rat model of cerebral palsy. These improvements were accompanied by enhanced neurogenesis, likely mediated by HGF secretion and activation of the PI3K-Akt signaling pathway. SHED is a promising candidate for postsymptom-onset treatment of cerebral palsy. Further studies to confirm these findings and examine the clinical utility of SHED are warranted.

Radiation-induced brain injury is caused by repeated radiation therapy for brain tumors and leukemia. Effective treatments for radiation-induced brain injury have not been developed. This study aimed to investigate the neuroprotective effects of umbilical cord-derived mesenchymal stromal cells (UC-MSCs) on irradiated neurons. We irradiated fetal mouse cortical neurons followed by coculture with UC-MSCs in vitro. Radiation significantly reduced the number of MAP2-positive mature and GAP43-positive immature neurons with a shortened neurite length, whereas coculture with UC-MSCs significantly restored the number and length of both MAP2-positive and GAP43-positive neurons. Irradiation induced apoptosis/necrosis in neurons significantly, while UC-MSCs prevented the neurons from apoptosis to necrosis. The incidence of reactive oxygen species (ROS) increased significantly in irradiated neurons compared to the control group, whereas it was significantly attenuated by the coculture of UC-MSCs. In conclusion, these results suggest that UC-MSCs have potential neuroprotective effects against radiation-induced brain injury by reducing oxidative stress.

Stem cells are the basis of organogenesis and regeneration, providing cellular support during the development, maintenance, and repair of tissues. This review provides a brief overview of the major stem cell types and their sources, as well as the key stages of organogenesis that depend on stem cell activity. This review highlights critical signalling pathways, including Wnt, Notch, Hedgehog, and BMP. These pathways regulate the fate and lineage specification of stem cells. The review identifies the roles of embryonic stem cells and induced pluripotent stem cells in organ formation as well as the newly arising methods for directed differentiation. Mesenchymal stem cells play a crucial role in tissue regeneration and therapeutic repair. Organoids are potent experimental models for studying development and disease. The impact of stem cell niches and microenvironmental regulation is discussed, along with the cellular and molecular processes that underlie recovery after damage. The review encompasses the translational progress of stem-cell-based therapies, current clinical trials, and the challenges in safety and efficacy. Moreover, the review also explores the introduction of advanced technologies, such as CRISPR, 3D bioprinting, and synthetic biology, as well as theoretical considerations, including future directions and ethical issues. Together, these insights provide a comprehensive overview of stem cell biology and highlight their potential for clinical translation.

Background: Ovarian aging (OA), which is characterized by a decline in the quality and quantity of oocytes, represents a major challenge in reproductive medicine. However, the therapeutic targets and therapeutic methods of OA remain poorly defined. Previous studies have suggested that the embryonic stem cells (ESCs) resist mammalian OA, yet the underlying molecular mechanisms are unclear.

Methods: To assess CNOT3's role in OA and oocyte maturation, we employed RT-qPCR, Western blotting, micro-injection, and RNA seq. RNA-seq, RT-qPCR, and Western blot were used to prove the effects of Cnot3 on the differentiation of mouse ESCs into primordial germ cell-like cells (PGCLCs). Mouse ESCs were injected into mice to evaluate the therapeutic benefit of ESCs on OA.

Results: In this study, we demonstrated that the CCR4-NOT transcription complex subunit 3 (CNOT3) played a critical regulator of OA resistance. Our results revealed that the expression of CNOT3 significantly decreased in aging ovaries of pigs and mice, compared with young ovaries. Using RNA-seq and micro-injection, we proved that CNOT3 resisted porcine OA by accelerating oocyte maturation. Moreover, Cnot3 upregulated the expressions of pluripotent genes in mouse ESCs and promoted the differentiation of ESCs into PGCLCs in vitro. Importantly, we found that tail vein injection of ESCs resisted mouse OA, while the therapeutic effects of ESCs on OA were reversed by knockdown of Cnot3.

Conclusion: Overall, our results indicated that CNOT3 counteracted OA and enhanced the therapeutic benefit of ESCs on OA. These findings will provide useful information for the improvement of therapeutic methods of OA.

Background: Inherited cardiomyopathy (ICM) is a genetic disorder characterized by abnormal myocardial structure and function, often progressing to heart failure. FHOD3, a member of the Formin gene family, plays a crucial role in cardiomyocyte cytoskeletal organization. Mutations in FHOD3 have been associated with various cardiomyopathies, including hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM) and left ventricular noncompaction (LVNC). However, the molecular mechanisms underlying FHOD3 deficiency-induced cardiomyopathy remain elusive.

Methods: A FHOD3 knockout (FHOD3^-/-) human embryonic stem cell (hESC) line was generated using the CRISPR/Cas9 system and subsequently differentiated into cardiomyocytes (hESC-CMs). Sarcomere structure, calcium handling, mitochondrial function, and contractility were evaluated via immunofluorescence, electron microscopy, Seahorse metabolic analysis, and high-definition video analysis, respectively. Transcriptomic sequencing was performed to identify differentially expressed genes and enriched pathways.

Results: FHOD3-deficient hESC-CMs exhibited marked sarcomere disorganization and degradation, impaired calcium handling and compromised mitochondrial function, ultimately leading to reduced contractility. Transcriptomic analysis revealed significant downregulation of sarcomere-related genes and calcium-handling genes, with enrichment in pathways associated with cardiomyopathy and calcium signaling. Furthermore, FHOD3 deficiency triggered the phosphorylation of CaMKII (Thr286), a key regulator of cardiac hypertrophy and remodeling, contributing to the progression of heart failure. Treatment with the myosin activator Omecamtiv mecarbil (OM) partially restored contractility without affecting calcium handling, highlighting its potential as a therapeutic strategy.

Conclusions: Our study establishes a valuable human-derived model for investigating the molecular mechanisms of FHOD3 deficiency-induced cardiomyopathy. This model allows for extensive investigation into the phenotypes caused by FHOD3 deficiency and identifies CaMKII activation as a crucial factor contributing to the HF phenotype. Additionally, this model serves as an important tool for discovering novel therapeutic agents, and we demonstrate that OM can partially improve myocardial function in FHOD3 KO hESC-CMs.

Background: Periodontitis, the leading cause of tooth loss worldwide, is closely linked to the compromised regenerative capacity of human periodontal ligament stem cells (hPDLSCs). Stem cell-based tissue engineering is a promising treatment for periodontitis. Sustaining the osteogenic potential of hPDLSCs against adverse conditions following transplantation is critical for successful periodontal tissue engineering. Recent research increasingly underscores ferroptosis as a crucial target for periodontitis treatment, whereas reactive oxygen species (ROS) contribute to ferroptosis initiation and progression. Klotho, an anti-aging protein, has been shown to protect hPDLSC osteogenic function under oxidative stress in our previous study. However, whether Klotho can provide protection against ferroptosis and maintain osteogenic function of hPDLSCs in an inflammatory environment remains elusive.

Methods: Ferroptosis level and the expression of Klotho in hPDLSCs under normal and inflammatory conditions were compared via single-cell RNA sequencing and validation experiments. Stable Klotho-overexpressing hPDLSCs (hPDLSCs-ov-KL) cell line was established and the impact of Klotho on ferroptosis was assayed. Subsequently, the effect of Klotho overexpression on hPDLSC osteogenesis was evaluated under in vitro inflammatory environment and in vivo periodontitis model of C57BL/6 mice. Additionally, the underlying molecular mechanism of Klotho effect on hPDLSCs under the inflammatory environment was investigated.

Results: Ferroptosis was activated and the expression of Klotho was reduced in hPDLSCs under LPS-stimulated inflammatory environment, consistent with the results in hPDLSCs of periodontitis via single-cell RNA sequencing. Further experiments confirmed Klotho overexpression effectively suppressed ferroptosis in hPDLSCs and markedly preserved the hPDLSC osteogenic capacity under in vitro inflammatory environment. In vivo, injection of hPDLSCs-ov-KL could effectively promote periodontal tissue repair in the mouse model of periodontitis. From the perspective of molecular mechanism, Klotho notably inhibited NOX4 expression in hPDLSCs under the inflammatory environment and NOX4 overexpression in hPDLSCs-ov-KL significantly increased intracellular ferroptosis, leading to compromised Klotho protective effect.

Conclusion: Our study highlighted the significant protective effect of Klotho on counteracting hPDLSC ferroptosis via the inhibition of NOX4 expression, therefore restoring the impaired osteogenic function of hPDLSCs in both in vitro inflammatory environment and in vivo periodontitis model, which might provide a promising strategy for periodontal tissue regeneration engineering.

Aim: Circular RNAs (circRNAs) have been identified as key regulators in inflammatory diseases, yet their function in pulpitis is unclear. This study investigates their potential role in the progression of pulpitis.

Methodology: Microarray and single-cell RNA sequencing were applied to assess DNA damage responses (DDR) in inflammatory pulp and its derived stem cells, respectively. qRT-PCR and Western blot were employed to detect the DNA double-strand break (DSB) marker γ-H2AX and inflammatory cytokines in pulp tissue. Bioinformatics analysis was used to identify upregulated circRNAs in inflamed DPSCs. Functional assays were performed to assess the impact of circ_0042103 on LPS-driven cellular damage and inflammation in DPSCs. The interaction between circ_0042103 and TAF15 was investigated using RNA FISH, pulldown, and nuclear-cytoplasmic fractionation assays. Transfection with circ_0042103/TAF15-siRNA in DPSCs was carried out to evaluate activation of the nucleotide excision repair (NER) pathway and its regulatory effects on DNA damage and inflammation.

Results: DDR was activated in both pulpitis and inflamed DPSCs. DNA damage showed a positive correlation with inflammation in pulpitis. In vitro, circ_0042103 upregulation amplified LPS-stimulated DDR and inflammatory signaling, whereas its knockdown alleviated both effects. Mechanistically, circ_0042103 bound TAF15, leading to decreased levels of the NER-related proteins (ERCC1 and PCNA) and increased DNA damage and inflammation.

Conclusion: By interacting with TAF15, circ_0042103 reduces the levels of the NER-related proteins ERCC1 and PCNA, leading to increased DNA damage and inflammation in hDPSCs, thereby defining a circ_0042103/TAF15/NER axis in pulpitis progression.

Background: The human endometrium is a regenerative tissue essential for fertility, but pathological conditions like Asherman syndrome, endometrial atrophy, and thin endometrium can impair its function. Current therapies lack efficacy, driving demand for innovative regenerative therapies. In this context, endometrial-derived hydrogels and organoids have shown promise individually for tissue regeneration, but their combined therapeutic potential has not been previously evaluated in vivo. This study explores a dual regenerative strategy combining a hybrid hydrogel - composed of synthetic PuraMatrix^® and endometrial extracellular matrix hydrogel - with human endometrial organoids in an immunocompetent murine model with uterine damage.

Methods: Endometrial damage model was established in female C57BL/6 mice (n = 46) via uterine injury using 70° ethanol. After 4 days of endometrial damage, human endometrial organoids were co-injected with the hybrid hydrogel into the uterine horns. Two weeks post-injection, a subset of mice (n = 25) was sacrificed for biocompatibility, histological, and transcriptomic analyses. Functional recovery of the endometrium was assessed in the remaining animals (n = 21) through fertility outcome evaluation. For endometrial regeneration analyses, normally distributed data were analyzed by one-way ANOVA and Tukey's multiple comparisons, while non-normally distributed data were analyzed by the Kruskal-Wallis test with Dunn's multiple comparisons. For fertility outcomes, t-test or Mann-Whitney U tests for 2-by-2 comparisons were performed.

Results: Histological and molecular analyses revealed that the therapy improved endometrial thickness, gland density, and vascularization, and reduced fibrosis and ferroptosis, aligning tissue characteristics closer to healthy controls. However, fertility outcomes were not fully restored, potentially due to the persistence of the synthetic component of the hybrid hydrogel. Thus, further studies are needed to confirm complete hydrogel resorption and its impact on fertility restoration.

Conclusions: In conclusion, this study demonstrates the biocompatibility and regenerative potential of human endometrial organoids delivered within the hybrid hydrogel, highlighting a promising strategy for endometrial regeneration.

Mesenchymal stem cells (MSCs) have been extensively investigated and applied in autoimmune and inflammatory diseases owing to their tissue-repair capacity and immunomodulatory properties, and they hold significant promise in cellular immunotherapy. However, therapeutic outcomes of stem-cell-based immunotherapy can be inconsistent, because the immunomodulatory effects of MSCs may undergo dynamic shifts in response to changes in the microenvironment. Research has shown that the inflammatory state of the tissue microenvironment affects the tendency of MSCs to regulate immunity. Under highly inflammatory conditions, MSCs tend to exert immunosuppressive functions, while under low inflammatory conditions, MSCs tend to exhibit immune support. In addition, the physical culture method, pretreatment conditions, and tissue source of stem cells all affect the direction of their immune regulation. Therefore, gaining a deep understanding of the immune regulatory mechanisms of MSCs and their influencing factors is crucial for optimizing their application in stem cell immunotherapy and improving treatment outcomes. This review first explores the potential factors influencing MSCs' bidirectional immune regulation, then discusses the mechanisms underlying the immunosupportive and immunosuppressive effects of MSCs, and finally briefly describes the role of MSCs' bidirectional immune regulation function in disease treatment.