Resveratrol Induces Differentiation of Human Umbilical Cord Mesenchymal Stem Cells into Neuron-Like Cells

The Role of Various Factors in Neural Differentiation of Human Umbilical Cord Mesenchymal Stem Cells with a Special Focus on the Physical Stimulants

Human umbilical cord matrix-derived mesenchymal stem cells (hUCMs) are considered as ideal tools for cell therapy procedures and regenerative medicine. The capacity of these cells to differentiate into neural lineage cells make them potentially important in the treatment of various neurodegenerative diseases. An electronic search was performed in Web of Science, PubMed/MEDLINE, Scopus and Google Scholar databases for articles published from January 1990 to March 2022. This review discusses the current knowledge on the effect of various factors, including physical, chemical and biological stimuli which play a key role in the differentiation of hUCMs into neural and glial cells. Moreover, the currently understood molecular mechanisms involved in the neural differentiation of hUCMs under various environmental stimuli are reviewed. Various stimuli, especially physical stimuli and specifically different light sources, have revealed effects on neural differentiation of mesenchymal stem cells, including hUCMs; however, due to the lack of information about the exact mechanisms, there is still a need to find optimal conditions to promote the differentiation capacity of these cells which in turn can lead to significant progress in the clinical application of hUCMs for the treatment of neurological disorders.

Potential of resveratrol in enrichment of neural progenitor-like cell induction of human stem cells from apical papilla

Introduction

Stem cell transplantation of exogenous neural progenitor cells (NPCs) derived from mesenchymal stem cells (MSCs) has emerged as a promising approach for neurodegenerative disease. Human stem cells from apical papilla (hSCAPs) are derived from migratory neural crest stem cells and exhibit a potential of neuronal differentiation. However, their neuronal differentiation is low and unpredictable. Resveratrol has been described as a sirtuin 1 (SIRT1) activator which plays an important role in enhancing neuronal differentiation. In this study, we investigate the potential of resveratrol as an enhancer on neuronal differentiation through NPCs induction of hSCAPs.

Methods

Stem cells were isolated from human apical papilla and characterized as MSCs. The cellular toxicity of resveratrol treatment to the characterized hSCAPs was investigated by MTT assay. The non-cellular toxicity concentrations of resveratrol were assessed with various pre-treatment times to select the optimal condition that highly expressed the neural progenitor gene, NES. Consequently, the optimal condition of resveratrol pre-treatment was synergistically performed with a neuronal induction medium to trigger neuronal differentiation. The differentiated cells were visualized, the genes profiling was quantified, and the percentage of neuronal differentiation was calculated. Moreover, the intracellular calcium oscillation was demonstrated.

Results

The cellular toxicity of resveratrol was not observed for up to 50 μM for 12 h. Interestingly, hSCAPs pre-treated with 10 μM resveratrol for 12 h (RSV-hSCAPs) significantly expressed NES, which is determined as the optimal condition. Under neuronal induction, both of hSCAPs and RSV-hSCAPs were differentiated (d-hSCAPs and RSV-d-hSCAPs) as they exhibited neuronal-like appearances with Nissl substance staining. The highest expression of NES and SOX1 was observed in RSV-d-hSCAPs. Additionally, the percentage of neuronal differentiation of RSV-d-hSCAPs was significantly higher than d-hSCAPs for 4 times. Importantly, the neuronal-like cells exhibited slightly increasing pattern of calcium intensity.

Conclusion

This study demonstrated that pre-treatment of resveratrol strongly induces neural progenitor marker gene expression which synergistically enhances neural progenitor-like cells’ induction with neuronal induction medium.

[Human umbilical cord mesenchymal stem cells differentiate into neuron-like cells after induction with B27-supplemented serum-free medium]

OBJECTIVE

To evaluate the capacity and efficiency of human umbilical cord mesenchymal stem cells (HUCMSCs) to differentiate into neuron- like cells after induction with B27- supplemented serum- free medium.

METHODS

HUCMSCs at passage 4 were cultured for 14 days with serum-containing medium (SCM) (group A), SCM supplemented with 20 ng/mL nerve growth factor (NGF) and 10 ng/mL basic fibroblast growth factor (bFGF) (group B), serum-free medium (SFM) (group C), or SFM supplemented with 20 ng/mL NGF and 10 ng/mL bFGF. The culture medium were changed every 3 days and the growth of the neurospheres was observed using an inverted microscope. The cell markers were analyzed with flow cytometry and the expressions of nestin, neuron- specific enolase (NSE), neurofilament heavy polypeptide (NEFH), and glial fibrillary acidic protein (GFAP) were quantified by quantitative real-time PCR (qRT-PCR) and Western blotting.

RESULTS

Before induction, HUCMSCs expressed abundant mesenchymal stem cell surface markers including CD29 (99.5%), CD44 (49.6%) and CD105 (77.7%). Neuron-like cells were observed in the cultures on days 7, 10, and 14, and the cell differentiation was the best in group D, followed by groups C, B and A. In all the 4 groups, the cellular expressions of nestin and GFAP gradually lowered while those of NEFH and NSE increased progressively. The expressions of GFAP, NEFH, nestin and NSE were significantly different between group A and the other 3 groups (P < 0.001 or 0.05).

CONCLUSIONS

B27-supplemented SFM effectively induces the differentiation of HUCMSCs into neuron- like cells, and the supplementation with cytokines (NGF and bFGF) strongly promotes the cell differentiation.

The Stemness of Human Ovarian Granulosa Cells and the Role of Resveratrol in the Differentiation of MSCs-A Review Based on Cellular and Molecular Knowledge

Ovarian Granulosa Cells (GCs) are known to proliferate in the developing follicle and undergo several biochemical processes during folliculogenesis. They represent a multipotent cell population that has been differentiated to neuronal cells, chondrocytes, and osteoblasts in vitro. However, progression and maturation of GCs are accompanied by a reduction in their stemness. In the developing follicle, GCs communicate with the oocyte bidirectionally via gap junctions. Together with neighboring theca cells, they play a crucial role in steroidogenesis, particularly the production of estradiol, as well as progesterone following luteinization. Many signaling pathways are known to be important throughout the follicle development, leading either towards luteinization and release of the oocyte, or follicular atresia and apoptosis. These signaling pathways include cAMP, PI3K, SMAD, Hedgehog (HH), Hippo and Notch, which act together in a complex manner to control the maturation of GCs through regulation of key genes, from the primordial follicle to the luteal phase. Small molecules such as resveratrol, a phytoalexin found in grapes, peanuts and other dietary constituents, may be able to activate/inhibit these signaling pathways and thereby control physiological properties of GCs. This article reviews the current knowledge about granulosa stem cells, the signaling pathways driving their development and maturation, as well as biological activities of resveratrol and its properties as a pro-differentiation agent.

Differentiation of Human Mesenchymal Stem Cells from Wharton's Jelly Towards Neural Stem Cells Using A Feasible and Repeatable Protocol

The transplantation of neural stem cells (NSCs) capable of regenerating to the cells of the central nervous system (CNS) is a promising strategy in the treatment of CNS diseases and injury. As previous studies have highlighted mesenchymal stem cells (MSCs) as a source of NSCs, this study aimed to develop a feasible, efficient, and reproducible method for the neural induction of MSCs isolated from Wharton's jelly (hWJ-MSCs). We induced neural differentiation in a monolayer culture using epidermal growth factor, basic fibroblast growth factor, N2, and B27 supplements. This resulted in a homogenous population of proliferating cells that expressed certain neural markers at both the protein and mRNA levels. Flow cytometry and immunocytochemistry confirmed the expression of neural markers: nestin, sex-determining region Y (SRY) box 1 and 2 (SOX1 and SOX2), microtubule-associated protein 2 (MAP2), and glial fibrillary acidic protein (GFAP). The qRT-PCR analysis revealed significantly enhanced expression of nestin and MAP2 in differentiated cells. This study confirms that it is possible to generate NSCs-like cells from hWJ-MSCs in a 2D culture using a practical method. However, the therapeutic effectiveness of such differentiated cells should be extended to confirm the terminal differentiation ability and electrophysiological properties of neurons derived from them.

Anti-stress, Glial- and Neuro-differentiation Potential of Resveratrol: Characterization by Cellular, Biochemical and Imaging Assays

Environmental stress, exhaustive industrialization and the use of chemicals in our daily lives contribute to increasing incidence of cancer and other pathologies. Although the cancer treatment has revolutionized in last 2–3 decades, shortcomings such as (i) extremely high cost of treatment, (ii) poor availability of drugs, (iii) severe side effects and (iv) emergence of drug resistance have prioritized the need of developing alternate natural, economic and welfare (NEW) therapeutics reagents. Identification and characterization of such anti-stress NEW drugs that not only limit the growth of cancer cells but also reprogram them to perform their specific functions are highly desired. We recruited rat glioma- and human neuroblastoma-based assays to explore such activities of resveratrol, a naturally occurring stilbenoid. We demonstrate that nontoxic doses of resveratrol protect cells against a variety of stresses that are largely involved in age-related brain pathologies. These included oxidative, DNA damage, metal toxicity, heat, hypoxia, and protein aggregation stresses. Furthermore, it caused differentiation of cells to functional astrocytes and neurons as characterized by the upregulation of their specific protein markers. These findings endorse multiple bioactivities of resveratrol and encourage them to be tested for their benefits in animal models and humans.

Dose-dependent effects of tetramethylpyrazine on the characteristics of human umbilical cord mesenchymal stem cells for stroke therapy

Umbilical cord mesenchymal stem cells (ucMSCs) may serve as a new source for cell therapy in stroke patients; however, the poor efficiency of viability, migration, and differentiation limit the application of ucMSCs. This study determined the dose-dependent effects of tetramethylpyrazine (TMP) on the characteristics of ucMSCs in vitro. The effect on proliferation was determined with Cell Counting kit-8 assays. Cell migration was analyzed with Transwell assays and western blot analysis. Differentiation of ucMSCs was evaluated according to markers and the expression of relevant proteins and genes. Secretion capacity was detected by ELISA analysis. TMP protected ucMSCs against H₂O₂ induced-oxidative damage but had no influence on ucMSC activity at a low concentration. Furthermore, ucMSC migration was improved by TMP via the SDF-1/CXCR4 axis. The observed effects were dose dependent. At a high dose, however, TMP induced the differentiation of ucMSCs into neuron-like cells that expressed neuron-specific markers. In addition, the secretion of cytokines was significantly increased by TMP. Therefore, TMP pre-treatment of ucMSCs may be an effective strategy to enhance the efficiency of ucMSC transplantation in stroke therapy.

The application of resveratrol to mesenchymal stromal cell-based regenerative medicine

Currently, the transplantation of mesenchymal stromal cells (MSCs) has emerged as an effective strategy to protect against tissue and organ injury. MSC transplantation also serves as a promising therapy for regenerative medicine, while poor engraftment and limited survival rates are major obstacles for its clinical application. Although multiple studies have focused on investigating chemicals to improve MSC stemness and differentiation in vitro and in vivo, there is still a shortage of effective and safe agents for MSC-based regenerative medicine. Resveratrol (RSV), a nonflavonoid polyphenol phytoalexin with a stilbene structure, was first identified in the root extract of white hellebore and is also found in the roots of Polygonum cuspidatum, and it is widely used in traditional Chinese medicine. RSV is a natural agent that possesses great therapeutic potential for protecting against acute or chronic injury in multiple tissues as a result of its antioxidative, anti-inflammatory, and anti-cancer properties. According to its demonstrated properties, RSV may improve the therapeutic effects of MSCs via enhancing their survival, self-renewal, lineage commitment, and anti-aging effects. In this review, we concluded that RSV significantly improved the preventive and therapeutic effects of MSCs against multiple diseases. We also described the underlying mechanisms of the effects of RSV on the survival, self-renewal, and lineage commitment of MSCs in vitro and in vivo. Upon further clarification of the potential mechanisms of the effects of RSV on MSC-based therapy, MSCs may be able to be more widely used in regenerative medicine to promote recovery from tissue injury.

Anti-aging effects exerted by Tetramethylpyrazine enhances self-renewal and neuronal differentiation of rat bMSCs by suppressing NF-kB signaling

In order to improve the therapeutic effects of mesenchymal stem cell (MSC)-based therapies for a number of intractable neurological disorders, a more favorable strategy to regulate the outcome of bone marrow MSCs (bMSCs) was examined in the present study. In view of the wide range of neurotrophic and neuroprotective effects, Tetramethylpyrazine (TMP), a biologically active alkaloid isolated from the herbal medicine Ligusticum wallichii, was used. It was revealed that treatment with 30–50 mg/l TMP for 4 days significantly increased cell viability, alleviated senescence by suppressing NF-κB signaling, and promoted bMSC proliferation by regulating the cell cycle. In addition, 40–50 mg/l TMP treatment may facilitate the neuronal differentiation of bMSCs, verified in the present study by presentation of neuronal morphology and expression of neuronal markers: microtubule-associated protein 2 (MAP-2) and neuron-specific enolase (NSE). The quantitative real-time polymerase chain reaction (qRT-PCR) revealed that TMP treatment may promote the expression of neurogenin 1 (Ngn1), neuronal differentiation 1 (NeuroD) and mammalian achaete–scute homolog 1 (Mash1). In conclusion, 4 days of 40–50 mg/l TMP treatment may significantly delay bMSC senescence by suppressing NF-κB signaling, and enhancing the self-renewal ability of bMSCs, and their potential for neuronal differentiation.

Autologous cord blood in children with cerebral palsy: a review

The aim of this narrative review is to report on the current knowledge regarding the clinical use of umbilical cord blood (CB) based on articles from PubMed and clinical trials registered on ClinicalTrials.gov. An increasing amount of evidence suggests that CB may be used for both early diagnostics and treatment of cerebral palsy. The acidity of CB and its biochemical parameters, including dozens of cytokines, growth factors, and other metabolites (such as amino acids, acylcarnitines, phosphatidylcholines, succinate, glycerol, 3-hydroxybutyrate, and O-phosphocholine) are predictors of future neurodevelopment. In addition, several clinical studies confirmed the safety and efficacy of CB administration in both autologous and allogeneic models, including a meta-analysis of five clinical trials involving a total of 328 participants. Currently, nine clinical trials assessing the use of autologous umbilical CB in children diagnosed with hypoxic-ischemic encephalopathy or cerebral palsy are in progress. The total population assessed in these trials exceeds 2500 patients.

The combined effect of mesenchymal stem cells and resveratrol on type 1 diabetic neuropathy

Diabetic neuropathy (DN) is one of the most common diabetic complications that results in an increase in patient discomfort and pain. The present study demonstrated that mesenchymal stem cells (MSCs) or resveratrol (RSV) may improve diabetic hyperglycemia and neuropathy. The aim of the present study was to investigate the combined effect of MSCs and RSV on DN. A total of 100 non-obese diabetic mice were divided into the following six groups: Normal control, MSCs, RSV, MSCs + RSV, insulin and diabetic control groups. Following homologous therapy, the levels of blood glucose and C-peptide, islets, nuclear factor (NF)-κB, nerve growth factor (NGF) and myelin basic protein (MBP), and the sciatic nerve structure in each group were examined and evaluated. Following the administration of therapy, the levels of blood glucose and C-peptide in mice in the MSCs + RSV group were significantly improved when compared with the other diabetic groups, and the dosage of insulin therapy required was the lowest among the six experimental groups (P<0.05). The levels of NGF, MBP and NF-κB in the MSCs + RSV group were significantly improved compared with the MSCs and RSV groups (P<0.05). Furthermore, the diameter of the axon, number of myelinated nerve fibers and the depth of the myelin sheath in the MSCs + RSV group were greatest among the five examined groups (excluding the control). The combination of RSV and MSCs could relieve hyperglycemia and improve DN. This indicated that the combination of RSV and MSCs may be a novel therapeutic method for the treatment of DN.

The use of mesenchymal stem cells for the treatment of progressive retinal diseases: a review

Some ocular diseases, such as dystrophies, retinal and macular degeneration, optic nerve atrophy, and Stargardt disease, are progressive and irreversible. In this review, we focus on the use of mesenchymal stem cells (MSCs) in the treatment of these diseases. In animal studies, MSC transplantation significantly delayed retinal degeneration, led to the regeneration of cone cells, and supported the survival of retinal ganglion cells and axon regeneration. In clinical practice, patients with Behcet's disease with retinal vasculitis who received MSC injections experienced a decrease in retinal vasculitis but no improvement in vision acuity. Nonetheless, there is no evidence that MSCs are carcinogenic, and they even reduce the size of tumors in vitro. Furthermore, MSCs do not trigger the immune response.

5-Azacytydine and resveratrol reverse senescence and ageing of adipose stem cells via modulation of mitochondrial dynamics and autophagy

Obesity and endocrine disorders have become prevalent issues in the field of both human and veterinary medicine. Equine metabolic syndrome is a complex disorder involving alternation in metabolism and chronic systemic inflammation. It has been shown that unfavourable microenvironment of inflamed adipose tissue negatively affects adipose stem cell population (ASC) residing within, markedly limiting their therapeutic potential. ASCs_EMS are characterized by increased senescence apoptosis, excessive accumulation of reactive oxygen species (ROS), mitochondria deterioration and “autophagic flux.” The aim of the present study was to evaluate whether treatment of ASCs_EMS with a combination of 5‐azacytydine (AZA) and resveratrol (RES) would reverse aged phenotype of these cells. For this reason, we performed the following analyzes: molecular biology (RT‐PCR), microscopic (immunofluorescence, TEM) and flow cytometry (JC‐1, ROS, Ki67). We evaluated the mitochondrial status, dynamics and clearance as well as autophagic pathways. Furthermore, we investigated epigenetic alternations in treated cells by measuring the expression of TET genes and analysis of DNA methylation status. We have demonstrated that AZA/RES treatment of ASCs_EMS is able to rejuvenate these cells by modulating mitochondrial dynamics, in particular by promoting mitochondrial fusion over fission. After AZA/RES treatment, ASCs_EMS were characterized by increased proliferation rate, decreased apoptosis and senescence and lower ROS accumulation. Our findings offer a novel approach and potential targets for the beneficial effects of AZA/RES in ameliorating stem cell dysfunctions.

Synaptic Plasticity of Human Umbilical Cord Mesenchymal Stem Cell Differentiating into Neuron-like Cells In Vitro Induced by Edaravone

Objective

The human umbilical cord mesenchymal stem cells (hUMSCs) are characterized with the potential ability to differentiate to several types of cells. Edaravone has been demonstrated to prevent the hUMSCs from the oxidative damage, especially its ability in antioxidative stress. We hypothesized that Edaravone induces the hUMSCs into the neuron-like cells.

Methods

The hUMSCs were obtained from the human umbilical cord tissue. The differentiation of hUMSCs was induced by Edaravone with three different doses: 0.65 mg/ml, 1.31 mg/ml, and 2.62 mg/ml. Flow cytometry was used to detect the cell markers. Protein and mRNA levels of nestin, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP) were detected by Western blot and RT-PCR. The expression of synaptophysin (SYN), growth-associated protein 43 (GAP43), and postsynaptic density 95 (PSD95) was detected by Real-Time PCR.

Results

As long as the prolongation of the culture, the hUMSCs displayed with the long strips or long fusiform to fat and then characterized with the radial helix growth. By using flow cytometry, the cultured hUMSCs at the 3rd, 5th, and 10th passages were expressed with CD73, CD90, and CD105 but not CD11b, CD19, CD34, CD45, and HLA-DR. Most of the hUMSCs cultured with Edaravone exhibited typical nerve-immediately characters including the cell body contraction, increased refraction, and protruding one or more elongated protrusions, which were not found in the control group without addition of Edaravone. NSE, nestin, and GFAP were positive in these neuron-like cells. Edaravone dose-dependently increased expression levels of NSE, nestin, and GFAP. After replacement of maintenance fluid, neuron-like cells continued to be cultured for five days. These neuron-like cells were positive for SYN, PSD95, and GAP43.

Conclusion

Edaravone can dose-dependently induce hUMSCs to differentiate into neuron-like cells that expressed the neuronal markers including NSE, nestin, and GFAP and synaptic makers such as SYN, PSD95, and GAP43.

Induction of Neuronal Differentiation of Murine N2a Cells by Two Polyphenols Present in the Mediterranean Diet Mimicking Neurotrophins Activities: Resveratrol and Apigenin

In the prevention of neurodegeneration associated with aging and neurodegenerative diseases (Alzheimer’s disease, Parkinson’s disease), neuronal differentiation is of interest. In this context, neurotrophic factors are a family of peptides capable of promoting the growth, survival, and/or differentiation of both developing and immature neurons. In contrast to these peptidyl compounds, polyphenols are not degraded in the intestinal tract and are able to cross the blood–brain barrier. Consequently, they could potentially be used as therapeutic agents in neurodegenerative pathologies associated with neuronal loss, thus requiring the stimulation of neurogenesis. We therefore studied the ability to induce neuronal differentiation of two major polyphenols present in the Mediterranean diet: resveratrol (RSV), a major compound found in grapes and red wine, and apigenin (API), present in parsley, rosemary, olive oil, and honey. The effects of these compounds (RSV and API: 6.25–50 µM) were studied on murine neuro-2a (N2a) cells after 48 h of treatment without or with 10% fetal bovine serum (FBS). Retinoic acid (RA: 6.25–50 µM) was used as positive control. Neuronal differentiation was morphologically evaluated through the presence of dendrites and axons. Cell growth was determined by cell counting and cell viability by staining with fluorescein diacetate (FDA). Neuronal differentiation was more efficient in the absence of serum than with 10% FBS or 10% delipidized FBS. At concentrations inducing neuronal differentiation, no or slight cytotoxicity was observed with RSV and API, whereas RA was cytotoxic. Without FBS, RSV and API, as well as RA, trigger the neuronal differentiation of N2a cells via signaling pathways simultaneously involving protein kinase A (PKA)/phospholipase C (PLC)/protein kinase C (PKC) and MEK/ERK. With 10% FBS, RSV and RA induce neuronal differentiation via PLC/PKC and PKA/PLC/PKC, respectively. With 10% FBS, PKA and PLC/PKC as well as MEK/ERK signaling pathways were not activated in API-induced neuronal differentiation. In addition, the differentiating effects of RSV and API were not inhibited by cyclo[DLeu⁵] OP, an antagonist of octadecaneuropeptide (ODN) which is a neurotrophic factor. Moreover, RSV and API do not stimulate the expression of the diazepam-binding inhibitor (DBI), the precursor of ODN. Thus, RSV and API are able to induce neuronal differentiation, ODN and its receptor are not involved in this process, and the activation of the (PLC/PKC) signaling pathway is required, except with apigenin in the presence of 10% FBS. These data show that RSV and API are able to induce neuronal differentiation and therefore mimic neurotrophin activity. Thus, RSV and API could be of interest in regenerative medicine to favor neurogenesis.

Abrus agglutinin stimulates BMP-2-dependent differentiation through autophagic degradation of β-catenin in colon cancer stem cells

Eradicating cancer stem cells (CSCs) in colorectal cancer (CRC) through differentiation therapy is a promising approach for cancer treatment. Our retrospective tumor-specimen analysis elucidated alteration in the expression of bone morphogenetic protein 2 (BMP-2) and β-catenin during the colon cancer progression, indicating that their possible intervention through "forced differentiation" in colon cancer remission. We reveal that Abrus agglutinin (AGG) induces the colon CSCs differentiation, and enhances sensitivity to the anticancer therapeutics. The low dose AGG (max. dose = 100 ng/mL) decreased the expression of stemness-associated molecules such as CD44 and β-catenin in the HT-29 cell derived colonospheres. Further, AGG augmented colonosphere differentiation, as demonstrated by the enhanced CK20/CK7 expression ratio and induced alkaline phosphatase activity. Interestingly, the AGG-induced expression of BMP-2 and the AGG-induced differentiation were demonstrated to be critically dependent on BMP-2 in the colonospheres. Similarly, autophagy-induction by AGG was associated with colonosphere differentiation and the gene silencing of BMP-2 led to the reduced accumulation of LC3-II, suggesting that AGG-induced autophagy is dependent on BMP-2. Furthermore, hVps34 binds strongly to BMP-2, indicating a possible association of BMP-2 with the process of autophagy. Moreover, the reduction in the self-renewal capacity of the colonospheres was associated with AGG-augmented autophagic degradation of β-catenin through an interaction with the autophagy adaptor protein p62. In the subcutaneous HT-29 xenograft model, AGG profoundly inhibited the growth of tumors through an increase in BMP-2 expression and LC3-II puncta, and a decrease in β-catenin expression, confirming the antitumor potential of AGG through induction of differentiation in colorectal cancer.