Current Stem Cell Research & Therapy - Online First

Epidermal growth factor-like domain-containing protein 6 (EGFL6) is a member of the epidermal growth factor superfamily. It has been reported that it can enhance the osteogenic differentiation potential of stem cells and stimulate angiogenesis. However, its effects on the regulation of odontogenic differentiation of dental pulp stem cells (DPSCs) have not been studied. Therefore, we aimed to investigate the role of EGFL6 in pulp regeneration and its underlying mechanism.

The cytotoxicity and migration-inductive ability of EGFL6 were evaluated using cell counting kit-8 assay and transwell assay, respectively. A tube formation assay was performed to assess the angiogenic effect of EGFL6. The alkaline phosphatase (ALP) and alizarin red S staining were conducted for mineralization evaluation. The odontoblastic-related and angiogenesis-related markers were measured by quantitative real-time polymerase chain reaction and Western blot analysis. Western blot was also conducted to further examine the levels of key factors involved in MAPK signaling pathways.

EGFL6 displayed no cytotoxicity and was capable of promoting cell migration and angiogenesis. Besides, EGFL6 enhanced the mineralization process and up-regulated the expression levels of odontoblastic-related markers (DSPP, DMP1, and BSP) after 5, 7, and 10 days. The expression levels of odontoblastic-related and angiogenesis-related proteins (DSPP, DMP1, VEGF, and ALP) could all be up-regulated by EGFL6. There was also an increase in the phosphorylation levels of ERK1/2 and P38.

EGFL6 can promote the migration, angiogenesis, and odontogenesis differentiation of DPSCs via the activation of MAPK signaling pathways.

Pulmonary fibrosis, a condition characterized by excessive lung tissue scarring, remains a significant therapeutic challenge. Given the potential of human Wharton’s jelly-derived mesenchymal stem cells (hWJ-MSCs) and their small extracellular vesicles (hWJ-MSC-EVs) as minimally invasive and scalable therapeutic options for pulmonary fibrosis in clinical settings, this study investigates the potential of hWJ-MSCs and hWJ-MSC-EVs in mitigating bleomycin-induced lung injury in C57BL/6J mice.

hWJ-MSCs were cultured and characterized for their ability to differentiate into osteogenic, adipogenic, and chondrogenic lineages. EVs were successfully induced via serum starvation, purified using ultracentrifugation, and characterized for their protein and nucleic acid content, size distribution, and EV markers. A bleomycin-induced pulmonary fibrosis model was established in C57BL/6J mice. Mice were monitored for weight loss, mortality, and lung fibrosis severity following treatment with hWJ-MSCs and hWJ-MSC-EVs. Histological analysis and Ashcroft scoring were used to assess lung fibrosis.

Bleomycin administration in mice resulted in significant weight loss, increased mortality, and severe lung fibrosis, as demonstrated by histological analysis and Ashcroft scoring. Treatment with hWJ-MSCs and hWJ-MSC-EVs significantly alleviated these symptoms. Mice receiving these treatments exhibited improved body weight, enhanced survival rates, and reduced lung fibrosis, with notable improvements in alveolar structure and decreased fibrotic tissue deposition.

These findings highlight the potential of hWJ-MSCs and hWJ-MSC-EVs as therapeutic agents in treating pulmonary fibrosis by reducing inflammation and promoting lung tissue repair, offering a potential new avenue for regenerative therapy in severe lung diseases. Future research directions involve elucidating the molecular pathways involved in tissue repair, optimizing therapeutic delivery, and conducting comprehensive clinical evaluations.

Neural stem cells (NSCs) are vulnerable to oxidative stress, which triggers aging and subsequently leads to a reduced regenerative capacity of the central nervous system (CNS). Due to the challenges in acquiring aged human NSCs and the lack of an oxidative stress-induced aging model specifically designed for human NSCs, research related to the aging mechanisms and the screening of anti-aging drugs has been limited. Here, we aimed to establish an oxidative stress-induced senescence model of NSCs by using D-galactose (D-gal).

Human embryonic stem cells (hESCs) were differentiated into hESC-NSCs using a type I collagen method. hESC-NSCs were characterized by flow cytometry combined with immunofluorescence. A senescence model of hESC-NSCs was established using D-gal and characterized by CCK-8 assay, neurosphere formation, crystal violet staining, DNA damage assay, SA-β-gal staining, and ROS levels measurement. To further explore the profile of gene expression in the D-gal-induced hESC-NSCs senescence model, transcriptome sequencing was performed and analysed by bioinformatics method, followed by verification using qPCR.

The hESC-derived NSCs senescence model demonstrated reduced proliferation and elevated β-galactosidase activity, accompanied by DNA damage, and increased levels of reactive oxygen species. Furthermore, transcriptome analysis unveiled the potential central role of the MAPK signaling pathway in D-gal-induced senescence, involving key genes, including DDIT3, ATF3, CEBPB, JUN, and CCND1.

We presented an oxidative stress-induced senescence model of hESC-NSCs and identified key pathways and genes related to D-gal-induced senescence. Our study might offer an alternative approach to investigating human NSCs aging and provide valuable data for understanding the underlying mechanisms of oxidative stress-induced aging.

Human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-Exs) have been found to exhibit therapeutic effects on inflammatory bowel disease (IBD). However, due to the harsh environment of the gastrointestinal tract, exosomes, as a type of biological drug or carrier of bio-active substances, are still delivered by tail vein injection.

In this study, hucMSC-Ex were coated with poly (lactic-co-glycolic acid) (PLGA) polymer to form microparticles, PLGA-hucMSC-Ex, by double emulsion method.

The oral administration of PLGA-hucMSC-Ex particles alleviated inflammation in the mice model of IBD by reversing IBD-induced epithelial-mesenchymal transition (EMT).

This provides an alternative to exploring IBD treatments, with potential clinical application to relieve IBD in patients.

Human menstrual blood stem cells (huMenSCs) appear to be pre-clinically safe but a controlled phase I clinical trial is required to determine safety for clinical applications.

HuMenSCs established from healthy donors were free of bacteria, mycoplasma, chlamydia, and endotoxin. P3 (passage 3) huMenSCs expressed the mesenchymal stem cell markers. P6 huMenSCs were developmental multipotential and could translocated into the uterine subepithelial stroma after intrauterine transplantation. After 10 and 15 passages, the huMenSCs kept normal karyotypes.

Gene expression showed that compared with the human umbilical cords mesenchymal stem cells (huMSCs), the huMenSCs affected the stromal cells more effectively. The huMenSCs possibly enhanced the stromal cell multiplication and “decidualization” process initiated by Igfbp1.

Expression of Igfbp1, Atf3, Ptgs2, Hoxa10, Nr4a1, and Fox A2 were significantly increased in the stromal cells of the huMenSCs transplanted uterine.

Since there is currently no cure for amyotrophic lateral sclerosis (ALS), it is essential to search for diagnostic biomarkers and novel treatments to reduce the severity of this disease. One of these treatment approaches is stem cell transplantation.

This study aims to evaluate the safety and efficacy of repeated transplantation of autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) in patients with ALS by analyzing clinical and molecular data.

This one-arm, single-center, open-label without a control group, prospective clinical trial, twenty-one confirmed ALS patients entered the study based on defined inclusion and exclusion criteria and underwent repeated stem cell transplantation (3 times BM-MSCs transplantation (1×10^6, MSC/Kg BW per injection) concurrently intrathecally (IT) and intravenously (IV), with one-month interval). Clinical assessment using ALS functional rating scale-revised (ALSFRS) and forced vital capacity (FVC) values and also molecular investigation by evaluating specific microRNAs expression (mir206, 133a-3p, 338-3p) in patient's serum and Cerebra spinal fluid (CSF) samples were done three times during the 3-month follow-up period.

No serious adverse effects were reported during the study. Besides, significant improvement in FVC when compared the baseline with the end of the research and the p-value was (0.036), and stability in ALSFRS was observed, and the p-value was (p=0.16) following stem cell transplantation in patients; also, the mentioned microRNA expression was non-significant (p > 0.05) as reported as well.

Our results demonstrated that repeated transplantation of BM-MSCs was a safe procedure in ALS patients, leading to delay in disease progression and improvement in clinical symptoms. Future studies are needed to confirm these results.

The osteogenic potential of periodontal ligament stem cells (PDLSCs) is crucial for periodontal tissue regeneration. Prolonged and excessive oxidative stress (OS) impairs the osteogenic function of PDLSCs. Recently, Semaphorin 3A (Sema3A) has been reported to have multiple roles in bone protection. This study aimed to investigate the protective effect of Sema3A on the osteogenic differentiation of PDLSCs under OS conditions induced by hydrogen peroxide (H2O2).

PDLSCs were subjected to H2O2 treatment to induce OS. The OS indices in PDLSCs were evaluated by analyzing levels of reactive oxygen species (ROS), cell viability, and expression of antioxidant factors using relevant assay kits. A small molecule inhibitor, XAV-939, was employed to block the Wnt/β-catenin pathway. Osteogenic differentiation was assessed using alkaline phosphatase (ALP) activity staining and Alizarin Red S (ARS) staining for mineralized nodules. Expression levels of osteogenic gene markers and β-catenin were determined via real-time quantitative polymerase chain reaction (RT-qPCR) or western blot (WB) analysis.

The stimulation of H2O2 induced OS in PDLSCs, resulting in a downregulation of Sema3A expression and a decrease in osteogenic markers, including ALP activity, mineralized nodule formation, and the expression of osteogenic genes (RUNX2 and ALP). However, the application of recombinant human Sema3A (rhSema3A) counteracted H2O2-induced OS and restored these osteogenic markers in PDLSCs under OS induced by H2O2. Mechanistic studies revealed that these effects were associated with an upregulation of β-catenin levels. Moreover, inhibiting β-catenin expression compromised the protective effect of Sema3A on osteogenesis in PDLSCs under OS.

Sema3A exerts a protective effect against H2O2-induced OS and activates the Wnt/β-catenin pathway to restore osteogenic differentiation impaired by OS in PDLSCs.

Idiopathic Nephrotic Syndrome (INS) is a common kidney disease in children, and the main clinical manifestations are hypoproteinaemia, proteinuria, hyperlipidaemia, and oedema. Mesenchymal Stem Cells (MSCs) are involved in tissue repair, protection against fibrosis, and immune modulation but have rarely been studied in INS.

This study aimed to explore the therapeutic potential of stem cells derived from human exfoliated deciduous teeth (SHEDs) in INS using an adriamycin-induced nephropathy (AN) rat model.

AN was induced in Sprague‒Dawley rats, and SHEDs were transplanted via the tail vein in single (SHED-s) and multidose (SHED-m) regimens. Cell migration assays were used to track the SHED distribution. Weight, urine protein, and serum biochemical assays were also performed. HE and Masson staining were used to observe glomerular and tubular damage, as well as the degree of fibrosis. Immunohistochemistry was used to label T lymphocytes and podocytes, and structural changes in podocytes were observed by electron microscopy. ELISA was used to measure the levels of inflammatory factors. Flow cytometry was used to analyse the balance of Th17 cells and Tregs. The mRNA expression of Th17- and Treg-associated cytokines and specific transcription factors was examined by RT‒PCR.

SHEDs directly migrated to damaged tissues, suggesting a targeted therapeutic effect. SHED transplantation significantly reduced proteinuria and reversed biochemical abnormalities in rats with AN. Both single and multidose SHED treatments could inhibit glomerular and tubular damage and delay the progression of fibrosis caused by adriamycin. SHEDs exerted a protective effect on podocytes. Additionally, this treatment inhibited inflammatory responses and corrected immune imbalances, as evidenced by decreased T lymphocyte infiltration, reduced serum levels of IL-6, TNF-a, and IL-1β, and modulation of the Th17/Treg balance.

In the AN rat model, SHED partly suppressed the development of inflammation and alleviated kidney injury, and immune regulation may be the underlying mechanism.