A comparative study of the capability of MSCs isolated from different human tissue sources to differentiate into neuronal stem cells and dopaminergic-like cells

Distinct anticancer properties of exosomes from induced mesenchymal stem cells vs. bone marrow-derived stem cells in MCF7 and A549 models

Mesenchymal stem cells (MSCs) have significant potential in regenerative medicine due to their multipotency, however, they face clinical challenges such as limited expansion and heterogeneity. Induced pluripotent stem cell-derived MSCs (iMSCs) are promising alternatives. The present study compared the effects of exosomes from bone marrow stromal MSCs (BMSCs) and iMSCs on A549 and MCF7 cancer cells to explore the unique properties of iMSCs. Proliferation assays revealed that both exosome types inhibited MCF7 and A549 cell proliferation at 24 h (P≤0.0001 for both) compared with the control, with BMSC-exosomes (Exos) exerting a more significant effect on MCF7 cells (P≤0.01). After 48 h, the significant effects of the BMSC-Exos were no longer observed on either cell line, whereas the iMSC-Exos continued to suppress A549 cell proliferation (P≤0.001 compared with the control; P≤0.01 compared with BMSC-Exos), indicating a longer-lasting effect. An investigation of senescence-associated β-galactosidase (SA-βGal) activity revealed no significant effect on senescence induction in MCF7 cells treated with either type of exosomes. By contrast, compared with the control treatment, the treatment of A549 cells with exosomes resulted in a significant increase in the number of senescent cells (P≤0.0001). While the apoptosis assay performed by flow cytometry revealed no significant effect on apoptosis, this increase in senescence aligned with the decreased proliferation observed in A549 cells, indicating that the antitumor effect of the exosomes on A549 cells was mediated partially through the induction of senescence. Wound healing assays revealed that BMSC-Exos significantly increased the migration of MCF7 cells at 20 h (P≤0.01). However, this effect was reversed at 47 h (P≤0.05), indicating a time-dependent effect of BMSC-Exos. In A549 cells, no significant difference in migration was observed after treatment with either exosome preparation. These findings highlight the distinct effects of iMSC- and BMSC-derived exosomes on cancer cells, emphasizing the need for further investigations into their therapeutic potential and underlying mechanisms.

The important role of the Wnt/β-catenin signaling pathway in small molecules mediated gingival mesenchymal stem cells transdifferentiate into neuron-like cells

OBJECTIVE

Given their neural crest origin, gingival mesenchymal stem cells (GMSCs) possess high neurogenic potential, which makes them suitable for cell replacement therapy against neurodegenerative diseases. This study investigated whether GMSCs can be transdifferentiated into neurons in vitro using a protocol involving small molecules VCRFY (VPA, CHIR99021, Repsox, Forskolin, and Y-27632). The regulatory mechanisms of key signaling pathways were also investigated.

METHODS

Neuronal induction of GMSCs was conducted using a small molecules-based protocol over 7 days, which included the evaluation of cell morphology, proliferation, expressions of neurogenic markers, and intracellular calcium oscillation. The activation of canonical the Wnt signaling pathway was assessed by examining the protein content and subcellular localization of β-catenin.

RESULTS

Small molecules-treated GMSCs displayed neuronal morphology and increased expression of neurogenic markers, including class III beta-tubulin (TUJ1), neuron-specific enolase (NSE), microtube-associated protein 2 (MAP2), and neurofilament medium (NFM), verified through RT-qPCR, western blotting, and immunocytochemistry. Based on the results of Fluo-4 AM calcium flux assay, small molecules-treated GMSCs exhibited enhanced electrophysiological activity. GMSC proliferation halted after 2 days of treatment. Among the small molecules, CHIR99021 exhibited the highest neuronal induction efficiency. Furthermore, activation of the Wnt/β-catenin signaling pathway augmented neuronal differentiation.

CONCLUSIONS

Small molecule-based cellular reprogramming can efficiently generate neurons from GMSCs, with Wnt/β-catenin signaling to play a critical role in neuronal induction.

Effect of cigarette smoke on the proliferation, viability, gene expression, and cellular functions of adipose-derived mesenchymal stem cells from smoking and non-smoking donors

Cigarette smoking negatively impacts mesenchymal stem cell functionality, including proliferation, viability, and differentiation potential. Adipose-derived mesenchymal stem cells (ADMSCs) are increasingly used for therapeutic purposes, but the specific effects of smoking in vivo on these cells are poorly understood. This study investigates the effects of cigarette smoke on the proliferation, viability, gene expression, and cellular functions of ADMSCs from smoking and non-smoking donors. In this study, ADMSCs were isolated from healthy smokers and non-smokers, and cell proliferation was assessed using the MTT assay, viability with apoptosis assays, mitochondrial membrane potential (MMP), and gene expression related to oxidative stress and cellular functions. Cell cycle analysis was also conducted. Our findings reveal a significant decrease in the proliferation of ADMSCs from smokers. Apoptosis assays showed reduced viable cells in smokers without a significant change in MMP, suggesting alternative pathways contributing to decreased viability. Gene expression analysis indicated the upregulation of genes associated with oxidative stress response and cellular defense mechanisms and the downregulation of genes related to inflammatory signaling, detoxification, and cellular metabolism. Cell cycle analysis indicates cycle arrest or delay in smokers, possibly due to stress and potential DNA damage. Smoking negatively affects ADMSCs' proliferation, viability, and function through oxidative stress and gene expression alterations. These findings highlight the importance of considering smoking status in ADMSC therapies and the need for further research to mitigate the effect of smoking on stem cells.

Effect of hypoxia on proliferation and differentiation of induced pluripotent stem cell-derived mesenchymal stem cells

Although mesenchymal stem cells (MSCs) are extensively applied in the regenerative field, the majority of MSCs die after a few weeks of transplantation. Therefore, hypoxia pre-conditioning is a crucial step in increasing the MSCs' tolerance to physiological conditions. Meanwhile, induced pluripotent stem cell-derived MSCs (iMSCs) were proposed as a possible alternative to MSCs, and recently, the interest is growing in applying iMSCs in the regenerative field. This study examined the effect of hypoxia pre-conditioning on the proliferation, viability, and differentiation of iMSCs. Both iMSCs and MSCs were subjected to two rounds of severe short-term hypoxia (1 % O2 for 24h). After that, iMSCs and MSCs were characterized by testing their surface markers' expression, proliferation, viability, oxidative stress, and differentiation potential. Our findings revealed that hypoxia did not have a consistent effect among all the analyzed lines: the severe short-term hypoxia (1 % O2) reduced iMSCs proliferation, cell viability, and MMP while showing a benign effect on surface markers expression, colony formation, ROS accumulation, and osteogenic and adipogenic differentiation. Though hypoxia adversely affected iMSCs' proliferation, this does not necessarily mean that hypoxia is harmful to iMSCs; on the contrary, our results suggest that short-term hypoxia might have a beneficial long-term effect on the proliferation of iMSCs. Thus, the effect of hypoxia on proliferation, viability, and differentiation should also be tested after a long recovery period from iMSCs. Our next step will be to test the effect of hypoxia for a longer period besides uncovering the changes in the expression profile of hypoxic iMSCs.

Unraveling the Exosome-miR-133a Axis: Targeting TGF-β Signaling via WJ-MSC-Derived Exosomes for Anti-Fibrotic Therapy in Liver Fibrosis

Background

One of the primary drivers of liver fibrosis is the excessive accumulation of extracellular matrix (ECM), primarily caused by the over-proliferation of hepatic star-shaped cells (HSCs). The activation of HSCs by transforming growth factor beta (TGF-β) has a critical role in initiating fibrosis. Recent studies have suggested that miRNA-133a significantly regulates the fibrogenesis process, which its downregulation is associated with the fibrosis progression. Understanding the role of miRNA-133a provides potential therapeutic insights for targeting TGF-β signaling and mitigating liver fibrosis. We investigated whether exosomes could attenuate liver fibrosis by enhancing the antifibrotic effects of miR-133a.

Methods

The LX-2 cell line was treated with TGF-β for 24 hours, followed by an additional 24 hours of treatment with exosomes. After this treatment period, we assessed the mRNA expression levels of α-SMA, collagen 1, and miR-133a, as well as the protein levels of p-Smad3.

Results

TGF-β exposure significantly increased the expression level of α-SMA and collagen 1 genes and elevated the levels of p-Smad3 protein. Additionally, it resulted in a significant downregulation of miR-133a compared to the control group. Exosome administration effectively reduced the TGF-β-induced upregulation of p-Smad3, α-SMA, and collagen 1 genes, but increased miR-133a expression levels.

Conclusion

Our findings indicate that by partially mitigating the downregulation of miR-133a, exosomes can effectively inhibit the persistent activation of HSCs. Furthermore, in the context of in vitro liver fibrosis, exosomes can suppress the TGF-β/Smad3 pathway, reducing the accumulation of ECM.

Cutting-edge regenerative therapy for Hirschsprung disease and its allied disorders

Hirschsprung disease (HSCR) and its associated disorders (AD-HSCR) often result in severe hypoperistalsis caused by enteric neuropathy, mesenchymopathy, and myopathy. Notably, HSCR involving the small intestine, isolated hypoganglionosis, chronic idiopathic intestinal pseudo-obstruction, and megacystis-microcolon-intestinal hypoperistalsis syndrome carry a poor prognosis. Ultimately, small-bowel transplantation (SBTx) is necessary for refractory cases, but it is highly invasive and outcomes are less than optimal, despite advances in surgical techniques and management. Thus, regenerative therapy has come to light as a potential form of treatment involving regeneration of the enteric nervous system, mesenchyme, and smooth muscle in affected areas. We review the cutting-edge regenerative therapeutic approaches for managing HSCR and AD-HSCR, including the use of enteric nervous system progenitor cells, embryonic stem cells, induced pluripotent stem cells, and mesenchymal stem cells as cell sources, the recipient intestine's microenvironment, and transplantation methods. Perspectives on the future of these treatments are also discussed.

Cell Transdifferentiation: A Challenging Strategy with Great Potential

With the discovery and development of somatic cell nuclear transfer, cell fusion, and induced pluripotent stem cells, cell transdifferentiation research has presented unique advantages and stimulated a heated discussion worldwide. Cell transdifferentiation is a phenomenon by which a cell changes its lineage and acquires the phenotype of other cell types when exposed to certain conditions. Indeed, many adult stem cells and differentiated cells were reported to change their phenotype and transform into other lineages. This article reviews the differentiation of stem cells and classification of transdifferentiation, as well as the advantages, challenges, and prospects of cell transdifferentiation. This review discusses new research directions and the main challenges in the use of transdifferentiation in human cells and molecular replacement therapy. Overall, such knowledge is expected to provide a deep understanding of cell fate and regulation, which can change through differentiation, dedifferentiation, and transdifferentiation, with multiple applications.

Molecular Mechanism of Long Noncoding RNA SNHG14 in Osteogenic Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells through the NEDD4L/FOXA2/PCP4 Axis

Bone marrow-derived mesenchymal stem cells (BMSCs) have a superior potential of osteogenic differentiation (OD) and a promising stem cell type to treat bone defects. This study sought to investigate the molecular mechanism of long noncoding RNA small nucleolar RNA host gene 14 (SNHG14) in OD of BMSCs. Western blot analysis or RT-qPCR showed that SNHG14, neural precursor cell expressed developmentally downregulated 4-like (NEDD4L), and Purkinje cell protein 4 (PCP4) were upregulated whereas forkhead box A2 (FOXA2) was declined in OD of BMSCs. RT-qPCR and cell staining showed that SNHG14 downregulation repressed OD of BMSCs, as manifested by reductions in osteopontin and osteocalcin levels, the mineralization degree, and alkaline phosphatase activity. RNA/Co/chromatin immunoprecipitation and dual-luciferase assays and determination of mRNA stability and ubiquitination level showed that SNHG14 bound to human antigen R improves NEDD4L mRNA stability and expression, further promoted FOXA2 ubiquitination to inhibit FOXA2 expression, and then reduced FOXA2 enrichment on the PCP4 promoter to upregulate PCP4 transcription. Functional rescue experiments showed that the overexpression of NEDD4L or PCP4 and knockdown of FOXA2 both attenuated the inhibition of SNHG14 downregulation on OD of BMSCs. Overall, our findings suggested that SNHG14 promoted OD of BMSCs through the NEDD4L/FOXA2/PCP4 axis.