Biological markers of mesenchymal stromal cells as predictors of response to autologous stem cell transplantation in patients with amyotrophic lateral sclerosis: an investigator-initiated trial and in vivo study

Cell therapy in ALS: An update on preclinical and clinical studies

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by the loss of motor neurons and neuromuscular impairment leading to complete paralysis, respiratory failure and premature death. The pathogenesis of the disease is multifactorial and noncell-autonomous involving the central and peripheral compartments of the neuromuscular axis and the skeletal muscle. Advanced clinical trials on specific ALS-related pathways have failed to significantly slow the disease. Therapy with stem cells from different sources has provided a promising strategy to protect the motor units exerting their effect through multiple mechanisms including neurotrophic support and excitotoxicity and neuroinflammation modulation, as evidenced from preclinical studies. Several phase I and II clinical trial of ALS patients have been developed showing positive effects in terms of safety and tolerability. However, the modest results on functional improvement in ALS patients suggest that only a coordinated effort between basic and clinical researchers could solve many problems, such as selecting the ideal stem cell source, identifying their mechanism of action and expected clinical outcomes. A promising approach may be stem cells selected or engineered to deliver optimal growth factor support at multiple sites along the neuromuscular pathway. This review covers recent advances in stem cell therapies in animal models of ALS, as well as detailing the human clinical trials that have been done and are currently undergoing development.

Ménière's Disease: Insights from an Italian Nationwide Survey

The aim of the present study was to obtain data from a large community sample of patients with Ménière's disease (MD) in Italy through a web-based nationwide survey. Demographic, clinical, and epidemiological features of MD among members of the Italian Association of Ménière's Disease (AMMI) were collected through a web-based survey. The questionnaire was posted on the AMMI website between 01/SEP/2021 and 31/OCT/2021. A total of 520 patients (374 F, 146 M) with MD were included. The age at interview (average ± standard deviation, SD) was 51.4 ± 10.9 years, with a disease duration of 9.9 ± 9.8 years. Eighty percent of cases were unilateral. No patients reported neurocognitive disorders or Parkinson's disease. A positive family history of MD was reported in 13% of participants, while a history of allergic diseases was reported in 33%. Comorbid thyroid disorders were present in 25% of participants, and 28% used betahistine as the main treatment. To our knowledge, this is the first study that has investigated the epidemiology and current patterns of care of MD in Italy, using an anonymous survey directly sent to patients, thus implying their active participation. We hope that future studies will support the utilization of web-based surveys to address the unmet needs in the management of patients with MD.

Stem Cell Therapies in Movement Disorders: Lessons from Clinical Trials

Stem cell-based therapies (SCT) to treat neurodegenerative disorders have promise but clinical trials have only recently begun, and results are not expected for several years. While most SCTs largely lead to a symptomatic therapeutic effect by replacing lost cell types, there may also be disease-modifying therapeutic effects. In fact, SCT may complement a multi-drug, subtype-specific therapeutic approach, consistent with the idea of precision medicine, which matches molecular therapies to biological subtypes of disease. In this narrative review, we examine published and ongoing trials in SCT in Parkinson's Disease, atypical parkinsonian disorders, Huntington's disease, amyotrophic lateral sclerosis, and spinocerebellar ataxia in humans. We discuss the benefits and pitfalls of using this treatment approach within the spectrum of disease-modification efforts in neurodegenerative diseases. SCT may hold greater promise in the treatment of neurodegenerative disorders, but much research is required to determine the feasibility, safety, and efficacy of these complementary aims of therapeutic efforts.

Therapeutic utility of mesenchymal stromal cell (MSC)-based approaches in chronic neurodegeneration: a glimpse into underlying mechanisms, current status, and prospects

Recently, mesenchymal stromal cell (MSC)-based therapy has become an appreciated therapeutic approach in the context of neurodegenerative disease therapy. Accordingly, a myriad of studies in animal models and also some clinical trials have evinced the safety, feasibility, and efficacy of MSC transplantation in neurodegenerative conditions, most importantly in Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington’s disease (HD). The MSC-mediated desired effect is mainly a result of secretion of immunomodulatory factors in association with release of various neurotrophic factors (NTFs), such as glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF). Thanks to the secretion of protein-degrading molecules, MSC therapy mainly brings about the degradation of pathogenic protein aggregates, which is a typical appearance of chronic neurodegenerative disease. Such molecules, in turn, diminish neuroinflammation and simultaneously enable neuroprotection, thereby alleviating disease pathological symptoms and leading to cognitive and functional recovery. Also, MSC differentiation into neural-like cells in vivo has partially been evidenced. Herein, we focus on the therapeutic merits of MSCs and also their derivative exosome as an innovative cell-free approach in AD, HD, PD, and ALS conditions. Also, we give a brief glimpse into novel approaches to potentiate MSC-induced therapeutic merits in such disorders, most importantly, administration of preconditioned MSCs.

Current Status of Mesenchymal Stem/Stromal Cells for Treatment of Neurological Diseases

Neurological disorders include a wide spectrum of clinical conditions affecting the central and peripheral nervous systems. For these conditions, which affect hundreds of millions of people worldwide, generally limited or no treatments are available, and cell-based therapies have been intensively investigated in preclinical and clinical studies. Among the available cell types, mesenchymal stem/stromal cells (MSCs) have been widely studied but as yet no cell-based treatment exists for neurological disease. We review current knowledge of the therapeutic potential of MSC-based therapies for neurological diseases, as well as possible mechanisms of action that may be explored to hasten the development of new and effective treatments. We also discuss the challenges for culture conditions, quality control, and the development of potency tests, aiming to generate more efficient cell therapy products for neurological disorders.

Mesenchymal stem cells for lysosomal storage and polyglutamine disorders: Possible shared mechanisms

BACKGROUND

Mesenchymal stem cells' (MSC) therapeutic potential has been investigated for the treatment of several neurodegenerative diseases. The fact these cells can mediate a beneficial effect in different neurodegenerative contexts strengthens their competence to target diverse mechanisms. On the other hand, distinct disorders may share similar mechanisms despite having singular neuropathological characteristics.

METHODS

We have previously shown that MSC can be beneficial for two disorders, one belonging to the groups of Lysosomal Storage Disorders (LSDs) - the Krabbe Disease or Globoid Cell Leukodystrophy, and the other to the family of Polyglutamine diseases (PolyQs) - the Machado-Joseph Disease or Spinocerebellar ataxia type 3. We gave also input into disease characterization since neuropathology and MSC's effects are intrinsically associated. This review aims at describing MSC's multimode of action in these disorders while emphasizing to possible mechanistic alterations they must share due to the accumulation of cellular toxic products.

RESULTS

Lysosomal storage disorders and PolyQs have different aetiology and associated symptoms, but both result from the accumulation of undegradable products inside neuronal cells due to inefficient clearance by the endosomal/lysosomal pathway. Moreover, numerous cellular mechanisms that become compromised latter are also shared by these two disease groups.

CONCLUSIONS

Here, we emphasize MSC's effect in improving proteostasis and autophagy cycling turnover, neuronal survival, synaptic activity and axonal transport. LSDs and PolyQs, though rare in their predominance, collectively affect many people and require our utmost dedication and efforts to get successful therapies due to their tremendous impact on patient s' lives and society.

Neuroinflammation in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia and the Interest of Induced Pluripotent Stem Cells to Study Immune Cells Interactions With Neurons

Inflammation is a shared hallmark between amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). For long, studies were conducted on tissues of post-mortem patients and neuroinflammation was thought to be only bystander result of the disease with the immune system reacting to dying neurons. In the last two decades, thanks to improving technologies, the identification of causal genes and the development of new tools and models, the involvement of inflammation has emerged as a potential driver of the diseases and evolved as a new area of intense research. In this review, we present the current knowledge about neuroinflammation in ALS, ALS-FTD, and FTD patients and animal models and we discuss reasons of failures linked to therapeutic trials with immunomodulator drugs. Then we present the induced pluripotent stem cell (iPSC) technology and its interest as a new tool to have a better immunopathological comprehension of both diseases in a human context. The iPSC technology giving the unique opportunity to study cells across differentiation and maturation times, brings the hope to shed light on the different mechanisms linking neurodegeneration and activation of the immune system. Protocols available to differentiate iPSC into different immune cell types are presented. Finally, we discuss the interest in studying monocultures of iPS-derived immune cells, co-cultures with neurons and 3D cultures with different cell types, as more integrated cellular approaches. The hope is that the future work with human iPS-derived cells helps not only to identify disease-specific defects in the different cell types but also to decipher the synergistic effects between neurons and immune cells. These new cellular tools could help to find new therapeutic approaches for all patients with ALS, ALS-FTD, and FTD.

Interplay between immunity and amyotrophic lateral sclerosis: Clinical impact

Amyotrophic lateral sclerosis (ALS) is a debilitating and rapidly fatal neurodegenerative disease. Despite decades of research and many new insights into disease biology over the 150 years since the disease was first described, causative pathogenic mechanisms in ALS remain poorly understood, especially in sporadic cases. Our understanding of the role of the immune system in ALS pathophysiology, however, is rapidly expanding. The aim of this manuscript is to summarize the recent advances regarding the immune system involvement in ALS, with particular attention to clinical translation. We focus on the potential pathophysiologic mechanism of the immune system in ALS, discussing local and systemic factors (blood, cerebrospinal fluid, and microbiota) that influence ALS onset and progression in animal models and people. We also explore the potential of Positron Emission Tomography to detect neuroinflammation in vivo, and discuss ongoing clinical trials of therapies targeting the immune system. With validation in human patients, new evidence in this emerging field will serve to identify novel therapeutic targets and provide realistic hope for personalized treatment strategies.

Mesenchymal Stromal Cells Perspective: New Potential Therapeutic for the Treatment of Neurological Diseases

Several studies have shown that mesenchymal stromal/stem cells (MSCs) exert their neuroprotective and neurorestorative efficacy via the secretion of neurotrophic factors. Based on these studies, many clinical trials using MSCs for the treatment of neurological disorders have been conducted, and results regarding their feasibility and efficacy have been reported. The present review aims to highlight the characteristics and basic research regarding the role of MSCs in neurological disease and to discuss the recent progress in clinical trials using MSCs to treat various neurological disorders.

Regenerative medicine for neurological diseases-will regenerative neurosurgery deliver?

Regenerative medicine aspires to transform the future practice of medicine by providing curative, rather than palliative, treatments. Healing the central nervous system (CNS) remains among regenerative medicine's most highly prized but formidable challenges. "Regenerative neurosurgery" provides access to the CNS or its surrounding structures to preserve or restore neurological function. Pioneering efforts over the past three decades have introduced cells, neurotrophins, and genes with putative regenerative capacity into the CNS to combat neurodegenerative, ischemic, and traumatic diseases. In this review we critically evaluate the rationale, paradigms, and translational progress of regenerative neurosurgery, harnessing access to the CNS to protect, rejuvenate, or replace cell types otherwise irreversibly compromised by neurological disease. We discuss the evidence surrounding fetal, somatic, and pluripotent stem cell derived implants to replace endogenous neuronal and glial cell types and provide trophic support. Neurotrophin based strategies via infusions and gene therapy highlight the motivation to preserve neuronal circuits, the complex fidelity of which cannot be readily recreated. We specifically highlight ongoing translational efforts in Parkinson's disease, amyotrophic lateral sclerosis, stroke, and spinal cord injury, using these to illustrate the principles, challenges, and opportunities of regenerative neurosurgery. Risks of associated procedures and novel neurosurgical trials are discussed, together with the ethical challenges they pose. After decades of efforts to develop and refine necessary tools and methodologies, regenerative neurosurgery is well positioned to advance treatments for refractory neurological diseases. Strategic multidisciplinary efforts will be critical to harness complementary technologies and maximize mechanistic feedback, accelerating iterative progress toward cures for neurological diseases.

Looking backward to move forward: a meta-analysis of stem cell therapy in amyotrophic lateral sclerosis

Transplantation of several types of stem cells (SC) for the treatment of amyotrophic lateral sclerosis (ALS) has been evaluated in numerous Phase I/II clinical trials with inconclusive results. Here, we conducted a meta-analysis to systematically assess the outcome of SC therapy trials which report the evolution of each patient before and after cell administration. In this way, we aimed to determine the effect of the SC intervention despite individual heterogeneity in disease progression. We identified 670 references by electronic search and 90 full-text studies were evaluated according to the eligibility criteria. Eleven studies were included comprising 220 cell-treated patients who received mesenchymal (M) SC (n = 152), neural (N) SC (n = 57), or mononuclear cells (MNC: CD34, CD117, and CD133 positive cells) (n = 11). Our analyses indicate that whereas intrathecal injection of mesenchymal stromal cells appears to have a transient positive effect on clinical progression, as measured by the ALS functional rating score, there was a worsening of respiratory function measured by forced vital capacity after all interventions. Based on current evidence, we conclude that optimal cell product and route of administration need to be determined in properly controlled preclinical models before further advancing into ALS patients. In addition, in-depth understanding of disease mechanisms in subsets of patients will help tailoring SC therapy to specific targets and increase the likelihood of improving outcomes.

Adipose-Derived Mesenchymal Stromal Cells in Regenerative Medicine: State of Play, Current Clinical Trials, and Future Prospects

Significance: Wound healing is a complex process involving pain and inflammation, where innervation plays a central role. Managing wound healing and pain remains an important issue, especially in pathologies such as excessive scarring (often leading to fibrosis) or deficient healing, leading to chronic wounds. Recent Advances: Advances in therapies using mesenchymal stromal cells offer new insights for treating indications that previously lacked options. Adipose-derived mesenchymal stromal cells (AD-MSCs) are now being used to a much greater extent in clinical trials for regenerative medicine. However, to be really valid, these randomized trials must imperatively follow strict guidelines such as consolidated standards of reporting trials (CONSORT) statement. Indeed, AD-MSCs, because of their paracrine activities and multipotency, have potential to cure degenerative and/or inflammatory diseases. Combined with their relatively easy access (from adipose tissue) and proliferation capacity, AD-MSCs represent an excellent candidate for allogeneic treatments. Critical Issues: The success of AD-MSC therapy may depend on the robustness of the biological functions of AD-MSCs, which requires controlling source heterogeneity and production processes, and development of biomarkers that predict desired responses. Several studies have investigated the effect of AD-MSCs on innervation, wound repair, or pain management separately, but systematic evaluation of how those effects could be combined is lacking. Future Directions: Future studies that explore how AD-MSC therapy can be used to treat difficult-to-heal wounds, underlining the need to thoroughly characterize the cells used, and standardization of preparation processes are needed. Finally, how this a priori easy-to-use cell therapy treatment fits into clinical management of pain, improvement of tissue healing, and patient quality of life, all need to be explored.

Repeat Administration of Bone Marrow-Derived Mesenchymal Stem Cells for Treatment of Amyotrophic Lateral Sclerosis

Background

The aim of this study was to investigate repeated intrathecal injection of autologous bone marrow-derived mesenchymal stem cells (BM-D MSCs) to patients for treatment of sporadic amyotrophic lateral sclerosis (ALS).

Material/Methods

Autologous MSCs were isolated from the patients’ bone marrow, plated, expanded, harvested, and passaged. Stem cells from a single bone marrow collection were used for 3 injections per patient, given over a 3-month period. Outcomes were measured with the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R). Participants were observed for a minimum of 6 months before transplantation to assess the natural course of ALS and for the same amount of time after transplantation to compare the rate of disease progression, estimated based on average monthly changes in ALSFRS-R scores. Data from 8 of the 15 participants eligible for the study were analyzed.

Results

The safety of the MSC injections was confirmed and various effects of the therapy were documented. In patients who had ALS with an inherently slow course, there were no significant changes in the rate of disease progression. In patients who had ALS with an inherently rapid course, slowing of the disease was noted following treatment with MSCs. However, because that subgroup was so small, it was not possible to assess whether the changes were statistically significant.

Conclusions

Identifying groups of patients who are not responding or potentially responding negatively to injection of MSCs may help prevent it from being offered to individuals who may not benefit from the therapy. One of the limitations of this treatment method is the amount of time required for long-lasting preparation of bone marrow-derived MSCs for a disease that is rapidly progressive. Therefore, it is worth looking for other allogeneic sources of stromal cells for these types of injections.

Therapeutic Effects of Human Mesenchymal Stem Cells in a Mouse Model of Cerebellar Ataxia with Neuroinflammation

Cerebellar ataxias (CAs) are neurological diseases characterized by loss of muscle coordination that is a result of damage and inflammation to the cerebellum. Despite considerable efforts in basic and clinical research, most CAs are currently incurable. In this study, we evaluated the therapeutic potential of human mesenchymal stem cells (hMSCs) against CAs associated with neuroinflammation. We observed that hMSC treatment significantly inhibited the symptoms of ataxia in lipopolysaccharide (LPS)-induced inflammatory CA (ICA) mice, which were recently reported as a potential animal model of ICA, through the anti-inflammatory effect of hMSC-derived TNFα-stimulated gene-6 (TSG-6), the protection of Purkinje cells by inhibition of apoptosis, and the modulatory effect for microglial M2 polarization. Thus, our results suggest that hMSC treatment may be an effective therapeutic approach for preventing or improving ataxia symptoms.

Repeated Application of Autologous Bone Marrow-Derived Lineage-Negative Stem/Progenitor Cells-Focus on Immunological Pathways in Patients with ALS

Therapeutic interventions in amyotrophic lateral sclerosis (ALS) are still far from satisfying. Immune modulating procedures raise hopes for slowing the disease progression. Stem cell therapies are believed to possess the ability to regulate innate and adaptive immune response and inflammation processes. Hence, three intrathecal administrations of autologous bone marrow-derived lineage-negative (Lin^–) cells were performed every six weeks in 40 sporadic ALS patients. The concentrations of inflammatory-related proteins and expression profiles of selected miRNA in the cerebrospinal fluid (CSF) and plasma at different timepoints post-transplantation were quantified by multiplex Luminex and qRT-PCR. The global gene expression in nucleated blood cells was assessed using the gene microarray technique. According to the ALS Functional Rating Scale (FRSr), the study population was divided into responders (group I, n = 17) and non-responders (group II, n = 23). A thorough analysis of the pro-inflammatory expression profiles, regulated miRNA pathways, and global gene expression profiles at the RNA level revealed the local and systemic effects of Lin^– cell therapy on the immune system of patients with ALS. The autologous application of Lin^– cells in CSF modulates immune processes and might prevent the progression of neurodegeneration. However, further in-depth studies are necessary to confirm the findings, and prolonged intervention is needed to maintain therapeutic effects.

Prevention of multiple system atrophy using human bone marrow-derived mesenchymal stem cells by reducing polyamine and cholesterol-induced neural damages

Background

Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder of unknown etiology, but is closely associated with damage to dopaminergic neurons. MSA progression is rapid. Hence, long-term drug treatments do not have any therapeutic benefits. We assessed the inhibitory effect of mesenchymal stem cells (MSCs) on double-toxin-induced dopaminergic neurodegenerative MSA.

Results

Behavioral disorder was significantly improved and neurodegeneration was prevented following MSC transplantation. Proteomics revealed lower expression of polyamine modulating factor-binding protein 1 (PMFBP1) and higher expression of 3-hydroxymethyl-3-methylglutaryl-CoA lyase (HMGCL), but these changes were reversed after MSC transplantation. In the in vitro study, the 6-OHDA-induced effects were reversed following co-culture with MSC. However, PMFBP1 knockdown inhibited the recovery effect due to the MSCs. Furthermore, HMGCL expression was decreased following co-culture with MSCs, but treatment with recombinant HMGCL protein inhibited the recovery effects due to MSCs.

Conclusions

These data indicate that MSCs protected against neuronal loss in MSA by reducing polyamine- and cholesterol-induced neural damage.

Mesenchymal Stem Cells from Human Exfoliated Deciduous Teeth and the Orbicularis Oris Muscle: How Do They Behave When Exposed to a Proinflammatory Stimulus?

Mesenchymal stem cells (MSCs) have been studied as a promising type of stem cell for use in cell therapies because of their ability to regulate the immune response. Although they are classically isolated from the bone marrow, many studies have sought to isolate MSCs from noninvasive sources. The objective of this study was to evaluate how MSCs isolated from the dental pulp of human exfoliated deciduous teeth (SHED) and fragments of the orbicularis oris muscle (OOMDSCs) behave when treated with an inflammatory IFN-γ stimulus, specifically regarding their proliferative, osteogenic, and immunomodulatory potentials. The results demonstrated that the proliferation of SHED and OOMDSCs was inhibited by the addition of IFN-γ to their culture medium and that treatment with IFN-γ at higher concentrations resulted in a greater inhibition of the proliferation of these cells than treatment with IFN-γ at lower concentrations. SHED and OOMDSCs maintained their osteogenic differentiation potential after stimulation with IFN-γ. Additionally, SHED and OOMDSCs have been shown to have low immunogenicity because they lack expression of HLA-DR and costimulatory molecules such as CD40, CD80, and CD86 before and after IFN-γ treatment. Last, SHED and OOMDSCs expressed the immunoregulatory molecule HLA-G, and the expression of this antigen increased after IFN-γ treatment. In particular, an increase in intracellular HLA-G expression was observed. The results obtained suggest that SHED and OOMDSCs lack immunogenicity and have immunomodulatory properties that are enhanced when they undergo inflammatory stimulation with IFN-γ, which opens new perspectives for the therapeutic use of these cells.

Biological functions of mesenchymal stem cells and clinical implications

Mesenchymal stem cells (MSCs) are isolated from multiple biological tissues-adult bone marrow and adipose tissues and neonatal tissues such as umbilical cord and placenta. In vitro, MSCs show biological features of extensive proliferation ability and multipotency. Moreover, MSCs have trophic, homing/migration and immunosuppression functions that have been demonstrated both in vitro and in vivo. A number of clinical trials are using MSCs for therapeutic interventions in severe degenerative and/or inflammatory diseases, including Crohn's disease and graft-versus-host disease, alone or in combination with other drugs. MSCs are promising for therapeutic applications given the ease in obtaining them, their genetic stability, their poor immunogenicity and their curative properties for tissue repair and immunomodulation. The success of MSC therapy in degenerative and/or inflammatory diseases might depend on the robustness of the biological functions of MSCs, which should be linked to their therapeutic potency. Here, we outline the fundamental and advanced concepts of MSC biological features and underline the biological functions of MSCs in their basic and translational aspects in therapy for degenerative and/or inflammatory diseases.

Safety and Feasibility of Repeated Intrathecal Allogeneic Bone Marrow-Derived Mesenchymal Stromal Cells in Patients with Neurological Diseases

Mesenchymal stromal cells (MSCs) have become the most commonly used adult stem cells in regenerative medicine. Preclinical studies have shown that MSCs-based therapy is a potential new treatment approach for neurological diseases. Intrathecal injection has unique feature which allows stem cells to directly migrate to the lesion site in patients with central nervous system (CNS) diseases. In this study, we evaluate the safety and feasibility of intrathecal allogeneic bone marrow-derived MSCs (BM-MSCs) in patients with neurological diseases. This open-label clinical study included 37 patients (14 diseases). Eligible patients underwent a baseline assessment and were intrathecally injected with allogeneic BM-MSCs (1 × 10⁶ cells/kg, 4 consecutive treatments at 1-week intervals). After four infusions, the patients were followed up for at least 6 months. Adverse events, cerebrospinal fluid (CSF) test results, clinical symptoms, physical examination, and haematological and imaging examinations were used to assess the safety and feasibility of the treatment. Also, we performed a systematic review of the safety of all types of intrathecal stem cells and compared our result to previous studies. In our study, the highest adverse event was a slight ache at the injection site (4.11%), followed by fever (3.42%) and mild headache (2.05%). No severe adverse events were reported. After the intrathecal injections, the white blood cell (WBC) counts in the CSF increased in 30 patients and the protein concentration in the CSF exceeded the normal range in 26 patients, while other CSF indicators remained normal. Moreover, these patients had no suspected manifestations of CNS infection. Haematological and imaging examinations showed no abnormal changes after BM-MSCs infusion. Compared with previous studies, the incidence of adverse events was nearly consistent or even lower for headache, fever, nausea, and neck pain. In conclusion, repeated intrathecal allogeneic BM-MSCs are safe, feasible, and promising for the treatment of patients with neurological diseases.

Regenerative Capacity of Adipose Derived Stem Cells (ADSCs), Comparison with Mesenchymal Stem Cells (MSCs)

Adipose tissue is now on the top one of stem cell sources regarding its accessibility, abundance, and less painful collection procedure when compared to other sources. The adipose derived stem cells (ADSCs) that it contains can be maintained and expanded in culture for long periods of time without losing their differentiation capacity, leading to large cell quantities being increasingly used in cell therapy purposes. Many reports showed that ADSCs-based cell therapy products demonstrated optimal efficacy and efficiency in some clinical indications for both autologous and allogeneic purposes, hence becoming considered as potential tools for replacing, repairing, and regenerating dead or damaged cells. In this review, we analyzed the therapeutic advancement of ADSCs in comparison to bone marrow (BM) and umbilical cord (UC)-mesenchymal stem cells (MSCs) and designed the specific requirements to their best clinical practices and safety. Our analysis was focused on the ADSCs, rather than the whole stromal vascular fraction (SVF) cell populations, to facilitate characterization that is related to their source of origins. Clinical outcomes improvement suggested that these cells hold great promise in stem cell-based therapies in neurodegenerative, cardiovascular, and auto-immunes diseases.

Regenerative Capacity of Adipose Derived Stem Cells (ADSCs), Comparison with Mesenchymal Stem Cells (MSCs)

Adipose tissue is now on the top one of stem cell sources regarding its accessibility, abundance, and less painful collection procedure when compared to other sources. The adipose derived stem cells (ADSCs) that it contains can be maintained and expanded in culture for long periods of time without losing their differentiation capacity, leading to large cell quantities being increasingly used in cell therapy purposes. Many reports showed that ADSCs-based cell therapy products demonstrated optimal efficacy and efficiency in some clinical indications for both autologous and allogeneic purposes, hence becoming considered as potential tools for replacing, repairing, and regenerating dead or damaged cells. In this review, we analyzed the therapeutic advancement of ADSCs in comparison to bone marrow (BM) and umbilical cord (UC)-mesenchymal stem cells (MSCs) and designed the specific requirements to their best clinical practices and safety. Our analysis was focused on the ADSCs, rather than the whole stromal vascular fraction (SVF) cell populations, to facilitate characterization that is related to their source of origins. Clinical outcomes improvement suggested that these cells hold great promise in stem cell-based therapies in neurodegenerative, cardiovascular, and auto-immunes diseases.

Ultrasensitive Fluorescence Detection of Alzheimer's Disease Based on Polyvalent Directed Peptide Polymer Coupled to a Nanoporous ZnO Nanoplatform

Amyloid-beta 42 (Aβ₄₂), the key biomarker of Alzheimer's disease (AD), aggregates to form neurotoxic amyloid plaques. In this work, we modified two fluorescein isothiocyanate-labeled Aβ₄₂-targeting peptides and designed an Aβ₄₂-specific ultrasensitive polyvalent-directed peptide polymer (PDPP) to enhance AD diagnosis sensitivity. The dissociation constant of Aβ₄₂ by PDPP was 10³-fold higher than the single-site-directed peptide. The improved binding was due to the ability of PDPP to detect multiple receptors on the target. The power of the PDPP diagnostic probe was verified in its application to detect Aβ₄₂ in cerebrospinal fluid (CSF), which showed a lower limit of detection (LOD) in the fg mL^-1 range that is more sensitive than detection by antibodies or single peptides. In addition, we present a novel ultrasensitive diagnostic system using an array of nanoporous ZnO nanoparticles, which play a role in fluorescence signal amplification, to further improve AD diagnosis sensitivity. We enhanced the signal on the basis of the properties of nanoporous ZnO nanoparticles and measured and quantified an ultralow concentration (ag mL^-1 range) of Aβ₄₂. This PDPP coupled to the nanoporous ZnO-based system is a novel approach to AD diagnosis that might also be useful for the detection of other target biomarkers and clinical applications.

Secretome of Mesenchymal Stem Cells and Its Potential Protective Effects on Brain Pathologies

Previous studies have indicated that mesenchymal stem cells (MSCs) have a fundamental role in the repair and regeneration of damaged tissues. There is strong evidence showing that much of the beneficial effects of these cells are due to the secretion of bioactive molecules-besides microRNAs, hormones, and neurotrophins-with anti-inflammatory, immunoregulatory, angiogenic, and trophic effects. These factors have been reported by many studies to possess protective effects on the nervous tissue. Although the beneficial effects of the secretory factors of MSCs have been suggested for various neurological diseases, their actions on astrocytic cells are not well understood. Hence, it is important to recognize the specific effects of MSCs derived from adipose tissue, in addition to the differences presented by the secretome, depending on the source and methods of analysis. In this paper, the different sources of MSCs and their main characteristics are described, as well as the most significant advances in regeneration and protection provided by the secretome of MSCs. Also, we discuss the possible neuroprotective mechanisms of action of the MSC-derived biomolecules, with special emphasis on the effect of MSCs derived from adipose tissue and their impact on glial cells and brain pathologies.

Mesenchymal Stem Cells: A Potential Therapeutic Approach for Amyotrophic Lateral Sclerosis?

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the degeneration of both upper and lower motor neurons. Patients show both motor and extra-motor symptoms. A cure is not available at this time, and the disease leads to death within 3-5 years, mainly due to respiratory failure. Stem cell therapy is arising as a new promising approach for the treatment of neurodegenerative disorders. In particular, mesenchymal stem cells (MSCs) seem the most suitable type of stem cells, thanks to their demonstrated beneficial effects in different experimental models, to the easy availability, and to the lack of ethical problems. In this review, we focused on the studies involving ALS rodent models and clinical trials in order to understand the potential beneficial effects of MSC transplantation. In different ALS rodent models, the administration of MSCs induced a delay in disease progression and at least a partial recovery of the motor function. In addition, clinical trials evidenced the feasibility and safety of MSC transplantation in ALS patients, given that no major adverse events were recorded. However, only partial improvements were shown. For this reason, more studies and trials are needed to clarify the real effectiveness of MSC-based therapy in ALS.

A Combination of Intrathecal and Intramuscular Application of Human Mesenchymal Stem Cells Partly Reduces the Activation of Necroptosis in the Spinal Cord of SOD1G93A Rats

An increasing number of studies have demonstrated the beneficial effects of human mesenchymal stem cells (hMSC) in the treatment of amyotrophic lateral sclerosis (ALS). We compared the effect of repeated intrathecal applications of hMSC or their conditioned medium (CondM) using lumbar puncture or injection into the muscle (quadriceps femoris), or a combination of both applications in symptomatic SOD1^G93A rats. We further assessed the effect of the treatment on three major cell death pathways (necroptosis, apoptosis, and autophagy) in the spinal cord tissue. All the animals were behaviorally tested (grip strength test, Basso Beattie Bresnahan (BBB) test, and rotarod), and the tissue was analyzed immunohistochemically, by qPCR and Western blot. All symptomatic SOD1 rats treated with hMSC had a significantly increased lifespan, improved motor activity and reduced number of Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positive cells. Moreover, a combined hMSC delivery increased motor neuron survival, maintained neuromuscular junctions in quadriceps femoris and substantially reduced the levels of proteins involved in necroptosis (Rip1, mixed lineage kinase‐like protein, cl‐casp8), apoptosis (cl‐casp 9) and autophagy (beclin 1). Furthermore, astrogliosis and elevated levels of Connexin 43 were decreased after combined hMSC treatment. The repeated application of CondM, or intramuscular injections alone, improved motor activity; however, this improvement was not supported by changes at the molecular level. Our results provide new evidence that a combination of repeated intrathecal and intramuscular hMSC applications protects motor neurons and neuromuscular junctions, not only through a reduction of apoptosis and autophagy but also through the necroptosis pathway, which is significantly involved in cell death in rodent SOD1^G93A model of ALS. stem cells translational medicine2019;8:535–547

Bone-marrow mononuclear cell therapy in a mouse model of amyotrophic lateral sclerosis: Functional outcomes from different administration routes

Amyotrophic lateral sclerosis (ALS) is a chronic degenerative disease that mainly affects motor neurons, leading to progressive paralysis and death. Recently, cell therapy has emerged as a therapeutic alternative for several neurological diseases, including ALS, and bone-marrow cells are one of the major cell sources. Considering the importance of pre-clinical trials to determine the best therapeutic protocol and the hope of translating this protocol to the clinical setting, we tested bone-marrow mononuclear cell (BMMC) therapy administered by different routes in the SOD1^G93A model of ALS. BMMCs were isolated from non-transgenic, age matched animals and administered intravenously (IV), intramuscularly (IM), and intravenously and intramuscular concomitantly (IV + IM). BMMC therapy had no significant beneficial effects when injected IV or IM, but delayed disease progression when these two routes were used concomitantly. BMMC IV + IM treatment reduced the number of microglia cells in the spinal cord and partially protected of neuromuscular-junction innervation, but had no effect in preventing motor-neuron loss. This study showed that injection of BMMC IV + IM had better results when compared to each route in isolation, highlighting the importance of targeting multiple anatomical regions in the treatment of ALS.

Ca2+-activated K+ channels modulate microglia affecting motor neuron survival in hSOD1G93A mice

Recent studies described a critical role for microglia in amyotrophic lateral sclerosis (ALS), where these CNS-resident immune cells participate in the establishment of an inflammatory microenvironment that contributes to motor neuron degeneration. Understanding the mechanisms leading to microglia activation in ALS could help to identify specific molecular pathways which could be targeted to reduce or delay motor neuron degeneration and muscle paralysis in patients. The intermediate-conductance calcium-activated potassium channel KCa3.1 has been reported to modulate the "pro-inflammatory" phenotype of microglia in different pathological conditions. We here investigated the effects of blocking KCa3.1 activity in the hSOD1G93AALS mouse model, which recapitulates many features of the human disease. We report that treatment of hSOD1G93A mice with a selective KCa3.1 inhibitor, 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34), attenuates the "pro-inflammatory" phenotype of microglia in the spinal cord, reduces motor neuron death, delays onset of muscle weakness, and increases survival. Specifically, inhibition of KCa3.1 channels slowed muscle denervation, decreased the expression of the fetal acetylcholine receptor γ subunit and reduced neuromuscular junction damage. Taken together, these results demonstrate a key role for KCa3.1 in driving a pro-inflammatory microglia phenotype in ALS.

Oxidative Stress in Mesenchymal Stem Cell Senescence: Regulation by Coding and Noncoding RNAs

SIGNIFICANCE

Mesenchymal stem cells (MSCs), adult stem cells with the potential of differentiation into mesodermal lineages, play an important role in tissue homeostasis and regeneration. In different organs, a subpopulation of MSCs is located near the vasculature and possibly represents the original source of lineage-committed mesenchymal progenitors. Recent Advances: The plasticity and immune characteristics of MSCs render them a preferential tool for regenerative cell therapy.

CRITICAL ISSUES

The culture expansion needed before MSC transplantation is associated with cellular senescence. Moreover, accelerated senescence of the total and perivascular MSC pool has been observed in humans and mouse models of premature aging disorders. MSC dysfunction is acknowledged as a culprit for the aging-associated degeneration of mesodermal tissues, but the underlying epigenetic pathways remain elusive. This article reviews current understanding of mechanisms impinging on MSC health, including oxidative stress, Nrf2-antioxidant responsive element activity, sirtuins, noncoding RNAs, and PKCs.

FUTURE DIRECTIONS

We provide evidence that epigenetic profiling of MSCs is utilitarian to the prediction of therapeutic outcomes. In addition, strategies that target oxidative stress-associated mechanisms represent promising approaches to counteract the detrimental effect of age and senescence in MSCs.-Antioxid. Redox Signal. 29, 864-879.

Repeated Intrathecal Mesenchymal Stem Cells for Amyotrophic Lateral Sclerosis

Objective

To assess the safety and efficacy of 2 repeated intrathecal injections of autologous bone marrow–derived mesenchymal stem cells (BM‐MSCs) in amyotrophic lateral sclerosis (ALS).

Methods

In a phase 2 randomized controlled trial (NCT01363401), 64 participants with ALS were randomly assigned treatments (1:1) of riluzole alone (control group, n = 31) or combined with 2 BM‐MSC injections (MSC group, n = 33). Safety was assessed based on the occurrence of adverse events. The primary efficacy outcome was changes in Amyotrophic Lateral Sclerosis Functional Rating Scale–Revised (ALSFRS‐R) score from baseline to 4 and 6 months postinjection. Post hoc analysis includes investigation of cerebrospinal fluid biomarkers and long‐term survival analysis.

Results

Safety rating showed no groupwise difference with absence of serious treatment‐related adverse events. Mean changes in ALSFRS‐R scores from baseline to 4 and 6 months postinjection were reduced in the MSC group compared with the control group (4 months: 2.98, 95% confidence interval [CI] = 1.48–4.47, p < 0.001; 6 months: 3.38, 95% CI = 1.23–5.54, p = 0.003). The MSC group showed decreased proinflammatory and increased anti‐inflammatory cytokines. In good responders, transforming growth factor β1 significantly showed inverse correlation with monocyte chemoattractant protein‐1. There was no significant difference in long‐term survival between groups.

Interpretation

Repeated intrathecal injections of BM‐MSCs demonstrated a possible clinical benefit lasting at least 6 months, with safety, in ALS patients. A plausible action mechanism is that BM‐MSCs mediate switching from pro‐ to anti‐inflammatory conditions. A future randomized, double‐blind, large‐scale phase 3 clinical trial with additional BM‐MSC treatments is required to evaluate long‐term efficacy and safety. Ann Neurol 2018;84:361–373

Mesenchymal stromal cells as a potential therapeutic for neurological disorders

Several studies have reported that mesenchymal stromal/stem cells (MSCs) restore neurological damage through their secretion of paracrine factors or their differentiation to neuronal cells. Based on these studies, many clinical trials have been conducted using MSCs for neurological disorders, and their safety and efficacy have been reported. In this review, we provide a brief introduction to MSCs, especially umbilical cord derived-MSCs (UC-MSCs), in terms of characteristics, isolation, and cryopreservation, and discuss the recent progress in regenerative therapies using MSCs for various neurological disorders.

TGF-β Inhibitor SB431542 Promotes the Differentiation of Induced Pluripotent Stem Cells and Embryonic Stem Cells into Mesenchymal-Like Cells

Due to their potential for tissue engineering applications and ability to modulate the immune system and reduce inflammation, mesenchymal stem cells (MSCs) have been explored as a promising option for the treatment of chronic diseases and injuries. However, there are problems associated with the use of this type of cell that limit their applications. Several studies have been exploring the possibility to produce mesenchymal stem cells from pluripotent stem cells (PSCs). The aim of these studies is to generate MSCs with advantageous characteristics of both PSCs and MSCs. However, there are still some questions concerning the characteristics of MSCs derived from the differentiation of PSCs that must be answered before they can be used to treat diseases and injuries. The objective of this study was, therefore, to determine if PSCs exposed to SB431542, a TGF-β inhibitor, are able to differentiate to MSCs, judging by morphology, expression of mesenchymal and pluripotent stem cell markers, expression of pluripotency-related genes, and ability to differentiate to osteocytes and adipocytes. The results obtained demonstrated that it is possible to induce the differentiation of both embryonic stem cells and induce pluripotent stem cells into cells with characteristics that highly resemble those from MSCs through the inhibition of the TGF-β pathway.

TGF-β and mesenchymal stromal cells in regenerative medicine, autoimmunity and cancer

Multipotent mesenchymal stromal cells (MSCs) represent a promising cell-based therapy in regenerative medicine and for the treatment of inflammatory/autoimmune diseases. Importantly, MSCs have emerged as an important contributor to the tumor stroma with both pro- and anti-tumorigenic effects. However, the successful translation of MSCs to the clinic and the prevention of their tumorigenic and metastatic effect require a greater understanding of factors controlling their proliferation, differentiation, migration and immunomodulation in vitro and in vivo. The transforming growth factor(TGF)-β1, 2 and 3 are involved in almost every aspect of MSC function. The aim of this review is to highlight the roles that TGF-β play in the biology and therapeutic applications of MSCs. We will discuss the how TGF-β modulate MSC function as well as the paracrine effects of MSC-derived TGF-β on other cell types in the context of tissue regeneration, immune responses and cancer. Finally, taking all these aspects into consideration we discuss how modulation of TGF-β signaling/production in MSCs could be of clinical interest.

Underregistration and Underreporting of Stem Cell Clinical Trials in Neurological Disorders

Background and Purpose

Research on stem cells (SC) is growing rapidly in neurology, but clinical applications of SC for neurological disorders remain to be proven effective and safe. Human clinical trials need to be registered in registries in order to reduce publication bias and selective reporting.

Methods

We searched three databases—clinicaltrials.gov, the Clinical Research Information System (CRIS), and PubMed—for neurologically relevant SC-based human trials and articles in Korea. The registration of trials, posting and publication of results, and registration of published SC articles were examined.

Results

There were 17 completed trials registered at clinicaltrials.gov and the CRIS website, with results articles having been published for 5 of them. Our study found 16 publications, of which 1 was a review article, 1 was a protocol article, and 8 contained registered trial information.

Conclusions

Many registered SC trials related to neurological disorders are not reported, while many SC-related publications are not registered in a public registry. These results support the presence of biased reporting and publication bias in SC trials related to neurological disorders in Korea.

Advances, challenges and future directions for stem cell therapy in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative condition where loss of motor neurons within the brain and spinal cord leads to muscle atrophy, weakness, paralysis and ultimately death within 3–5 years from onset of symptoms. The specific molecular mechanisms underlying the disease pathology are not fully understood and neuroprotective treatment options are minimally effective.

In recent years, stem cell transplantation as a new therapy for ALS patients has been extensively investigated, becoming an intense and debated field of study. In several preclinical studies using the SOD1^G93A mouse model of ALS, stem cells were demonstrated to be neuroprotective, effectively delayed disease onset and extended survival. Despite substantial improvements in stem cell technology and promising results in preclinical studies, several questions still remain unanswered, such as the identification of the most suitable and beneficial cell source, cell dose, route of delivery and therapeutic mechanisms. This review will cover publications in this field and comprehensively discuss advances, challenges and future direction regarding the therapeutic potential of stem cells in ALS, with a focus on mesenchymal stem cells. In summary, given their high proliferation activity, immunomodulation, multi-differentiation potential, and the capacity to secrete neuroprotective factors, adult mesenchymal stem cells represent a promising candidate for clinical translation. However, technical hurdles such as optimal dose, differentiation state, route of administration, and the underlying potential therapeutic mechanisms still need to be assessed.

The use of mesenchymal stem cells (MSCs) for amyotrophic lateral sclerosis (ALS) therapy – a perspective on cell biological mechanisms

Recent clinical trials of mesenchymal stem cells (MSCs) transplantation have demonstrated procedural safety and clinical proof of principle with a modest indication of benefit in patients with amyotrophic lateral sclerosis (ALS). While replacement therapy remained unrealistic, the clinical efficacy of this therapeutic option could be potentially enhanced if we could better decipher the mechanisms underlying some of the beneficial effects of transplanted cells, and work toward augmenting or combining these in a strategic manner. Novel ways whereby MSCs could act in modifying disease progression should also be explored. In this review, I discuss the known, emerging and postulated mechanisms of action underlying effects that transplanted MSCs may exert to promote motor neuron survival and/or to encourage regeneration in ALS. I shall also speculate on how transplanted cells may alter the diseased environment so as to minimize non-neuron cell autonomous damages by immune cells and astrocytes.

Mammalian MSC from selected species: Features and applications

Mesenchymal stromal/stem cells (MSC) are promising candidates for cellular therapy of different diseases in humans and in animals. Following the guidelines of the International Society for Cell Therapy, human MSC may be identified by expression of a specific panel of cell surface markers (CD105+, CD73+, CD90+, CD34-, CD14-, or CD11b-, CD79- or CD19-, HLA-DR-). In addition, multiple differentiation potential into at least the osteogenic, adipogenic, and chondrogenic lineage is a main criterion for MSC definition. Human MSC and MSC of a variety of mammals isolated from different tissues meet these criteria. In addition to the abovementioned, they express many more cell surface markers. Yet, these are not uniquely expressed by MSC. The gross phenotypic appearance like marker expression and differentiation potential is similar albeit not identical for MSC from different tissues and species. Similarly, MSC may feature different biological characteristics depending on the tissue source and the isolation and culture procedures. Their versatile biological qualities comprising immunomodulatory, anti-inflammatory, and proregenerative capacities rely largely on the migratory and secretory capabilities of MSC. They are attracted to sites of tissue lesion and secrete factors to promote self-repair of the injured tissue. This is a big perspective for clinical MSC applications in both veterinary and human medicine. Phase I/II clinical trials have been initiated to assess safety and feasibility of MSC therapies in acute and chronic disease settings. Yet, since the mode of MSC action in a specific disease environment is still unknown at large, it is mandatory to unravel the response of MSC from a given source onto a specific disease environment in suitable animal models prior to clinical applications. © 2017 International Society for Advancement of Cytometry.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Concise Review: Mesenchymal Stem Cells in Neurodegenerative Diseases

Stem cell-based therapies for neurodegenerative diseases aim at halting clinical deterioration by regeneration and by providing local support for damaged tissue. Mesenchymal stem cells (MSCs) hold great potential for cell therapy as they can be efficiently derived from adult tissue, ex vivo expanded in culture and safely transplanted autologously. MSCs were also shown to be able to differentiate toward neural fates and to secrete a broad range of factors able to promote nervous tissue maintenance and repair. Moreover, upon transplantation, MSCs were shown capable of homing toward lesioned areas, implying their potential use as vehicles for therapeutic agents administration. Indeed, various advantageous effects were reported following human MSCs transplantation into rodent models of neurodegenerative diseases, such as neurotrophic factor-mediated protection, enhanced neurogenesis, modulation of inflammation, and abnormal protein aggregate clearance. Recent studies have also used ex vivo manipulation for enhanced expression of potentially favorable factors, by so exploiting the homing capacity of MSCs for effective expression at the lesion site. Here, we will summarize current advancements in MSCs-based therapies for neurodegenerative diseases. We will examine the roles of central mechanisms suggested to mediate the beneficial effects of MSCs-based therapy and consider the augmentation of these mechanisms for superior clinical outcomes in rodent models of neurodegeneration as well as in clinical trials.

Human bone marrow mesenchymal stem cells suppress the proliferation of hepatic stellate cells by inhibiting the ubiquitination of p27

Bone marrow mesenchymal stem cells (BMSCs) have considerable therapeutic potential for the treatment of end-stage liver disease. Previous studies have demonstrated that BMSCs secrete growth factors and cytokines that inactivate hepatic stellate cells (HSCs), which inhibited the progression of hepatic fibrosis. The aim of this study was to determine the mechanism by which BMSCs suppress the function of HSCs in fibrosis. Our results showed that co-culture of BMSCs and HSCs induced cell cycle arrest at the G10/G1 phase and cell apoptosis of HSCs, which finally inhibited the cell proliferation of HSCs. Consistent with the cell cycle arrest, co-culture of BMSCs and HSCs increased the abundance of the cell cycle protein p27. Mechanistically, we further uncovered that following the co-culture with BMSCs, the expression level of the E3 ligase S-phase kinase-associated protein 2 (SKP2) that is responsible for the ubiquitination of p27 was decreased, which attenuated the ubiquitination of p27 and increased the stability of p27 in HSCs. Collectively, our results indicated the potential involvement of the SKP2-p27 axis for the inhibitory effect of BSMCs on the cell proliferation of HSCs.