Anti-apoptotic Effects of Human Wharton's Jelly-derived Mesenchymal Stem Cells on Skeletal Muscle Cells Mediated via Secretion of XCL1

Application of mesenchymal stem cells derived from the umbilical cord or Wharton's jelly and their extracellular vesicles in the treatment of various diseases

Mesenchymal stem cells (MSCs) originating from the umbilical cord (UC) or Wharton's jelly (WJ) have attracted substantial interest due to their potential to augment therapeutic approaches for a wide range of disorders. These cells demonstrate a wide range of capabilities in the process of differentiating into a multitude of cell types. Additionally, they possess a significant capacity for proliferation and are conveniently accessible. Furthermore, they possess a status of being immune-privileged, exhibit minimal tumorigenic characteristics, and raise minimal ethical concerns. Consequently, they are well-suited candidates for tissue regeneration and the treatment of diseases. Additionally, UC-derived MSCs offer a substantial yield compared to other sources. The therapeutic effects of these MSCs are closely associated with the release of nanosized extracellular vesicles (EVs), including exosomes and microvesicles (MVs), containing lipids, microRNAs, and proteins that facilitate intercellular communication. Due to their reduced tumorigenic and immunogenic characteristics, in addition to their convenient manipulability, EVs have arisen as a viable alternative for the management of disorders. The favorable characteristics of UC-MSCs or WJ-MSCs and their EVs have generated significant attention in clinical investigations encompassing diverse pathologies. Therefore, we present a review encompassing current preclinical and clinical investigations, examining the implications of UC-MSCs in diverse diseases, including those affecting bone, cartilage, skin, liver, kidney, neural, lung, cardiovascular, muscle, and retinal tissues, as well as conditions like cancer, diabetes, sepsis, and others.

Triptolide, a Cancer Cell Proliferation Inhibitor, Causes Zebrafish Muscle Defects by Regulating Notch and STAT3 Signaling Pathways

Triptolide is a natural compound in herbal remedies with anti-inflammatory and anti-proliferative properties. We studied its effects on critical signaling processes within the cell, including Notch1 and STAT3 signaling. Our research showed that triptolide reduces cancer cell proliferation by decreasing the expression of downstream targets of these signals. The levels of each signal-related protein and mRNA were analyzed using Western blot and qPCR methods. Interestingly, inhibiting one signal with a single inhibitor alone did not significantly reduce cancer cell proliferation. Instead, MTT assays showed that the simultaneous inhibition of Notch1 and STAT3 signaling reduced cell proliferation. The effect of triptolide was similar to a combination treatment with inhibitors for both signals. When we conducted a study on the impact of triptolide on zebrafish larvae, we found that it inhibited muscle development and interfered with muscle cell proliferation, as evidenced by differences in the staining of myosin heavy chain and F-actin proteins in confocal fluorescence microscopy. Additionally, we noticed that inhibiting a single type of signaling did not lead to any significant muscle defects. This implies that triptolide obstructs multiple signals simultaneously, including Notch1 and STAT3, during muscle development. Chemotherapy is commonly used to treat cancer, but it may cause muscle loss due to drug-related adverse reactions or other complex mechanisms. Our study suggests that anticancer agents like triptolide, inhibiting essential signaling pathways including Notch1 and STAT3 signaling, may cause muscle atrophy through anti-proliferative activity.

Nervonic Acid Inhibits Replicative Senescence of Human Wharton's Jelly-Derived Mesenchymal Stem Cells

Cellular senescence causes cell cycle arrest and promotes permanent cessation of proliferation. Since the senescence of mesenchymal stem cells (MSCs) reduces proliferation and multipotency and increases immunogenicity, aged MSCs are not suitable for cell therapy. Therefore, it is important to inhibit cellular senescence in MSCs. It has recently been reported that metabolites can control aging diseases. Therefore, we aimed to identify novel metabolites that regulate the replicative senescence in MSCs. Using a fecal metabolites library, we identified nervonic acid (NA) as a candidate metabolite for replicative senescence regulation. In replicative senescent MSCs, NA reduced senescence-associated β-galactosidase positive cells, the expression of senescence-related genes, as well as increased stemness and adipogenesis. Moreover, in non-senescent MSCs, NA treatment delayed senescence caused by sequential subculture and promoted proliferation. We confirmed, for the first time, that NA delayed and inhibited cellular senescence. Considering optimal concentration, duration, and timing of drug treatment, NA is a novel potential metabolite that can be used in the development of technologies that regulate cellular senescence.

Cell Therapy Strategies on Duchenne Muscular Dystrophy: A Systematic Review of Clinical Applications

Duchenne Muscular Dystrophy (DMD) is an inherited genetic disorder characterized by progressive degeneration of muscle tissue, leading to functional disability and premature death. Despite extensive research efforts, the discovery of a cure for DMD continues to be elusive, emphasizing the need to investigate novel treatment approaches. Cellular therapies have emerged as prospective approaches to address the underlying pathophysiology of DMD. This review provides an examination of the present situation regarding cell-based therapies, including CD133 + cells, muscle precursor cells, mesoangioblasts, bone marrow-derived mononuclear cells, mesenchymal stem cells, cardiosphere-derived cells, and dystrophin-expressing chimeric cells. A total of 12 studies were found eligible to be included as they were completed cell therapy clinical trials, clinical applications, or case reports with quantitative results. The evaluation encompassed an examination of limitations and potential advancements in this particular area of research, along with an assessment of the safety and effectiveness of cell-based therapies in the context of DMD. In general, the available data indicates that diverse cell therapy approaches may present a new, safe, and efficacious treatment modality for patients diagnosed with DMD. However, further studies are required to comprehensively understand the most advantageous treatment approach and therapeutic capacity.

Human umbilical cord blood-derived mesenchymal stem cells restored hematopoiesis by improving radiation induced bone marrow niche remodeling in rats

BACKGROUND

Functional hematopoiesis is governed by the bone marrow (BM) niche, which is compromised by radiotherapy, leading to radiation induced BM failure. The aim of this study was to demonstrate the radiation induced pathological remodeling of the niche and the efficacy of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) in restoring hematopoiesis via improvement of the niche.

METHODS

Thirty male Wistar rats were equally assigned to three groups: control (CON), irradiated (IR), and IR+hUCB-MSCs. Biochemical, histopathological and immunohistochemical analyses were performed to detect collagen type III and IV, Aquaporin 1+ sinusoidal endothelial cells and immature hematopoietic cells, CD11c+ dendritic cells, Iba1+ macrophages, CD9+ megakaryocytes, Sca-1+, cKit+, CD133 and N-cadherin+ hematopoietic stem and progenitor cells, CD20+, Gr1+ mature hematopoietic cells, in addition to ki67+ proliferation, Bcl-2+ anti-apoptotic, caspase-3+ apoptotic, TNF-α+ inflammatory cells. Histoplanimetry data were statistically analyzed using the one-way analysis of variance followed by the post hoc Duncan's test. Moreover, Pearson's correlation was used to assess the correlation between various parameters.

RESULTS

In comparison to the IR group, the IR+hUCB-MSCs group showed restored cell populations and extracellular collagen components of the BM niche with significant increase in hematopoietic stem, progenitor, mature and proliferating cells, and a considerable decrease in apoptotic and inflammatory cells. Furthermore, highly significant correlations between BM niche and blood biochemical, histopathological, and immunohistochemical parameters were observed.

CONCLUSION

hUCB-MSCs restored functional hematopoiesis through amelioration of the BM niche components via reduction of oxidative stress, DNA damage, inflammation, and apoptosis with upregulation of cellular proliferation.

Adipose Tissue and Adipose-Tissue-Derived Cell Therapies for the Treatment of the Face and Hands of Patients Suffering from Systemic Sclerosis

Adipose tissue is recognized as a valuable source of cells with angiogenic, immunomodulatory, reparative and antifibrotic properties and emerged as a therapeutic alternative for the regeneration and repair of damaged tissues. The use of adipose-tissue-based therapy is expanding in autoimmune diseases, particularly in Systemic Sclerosis (SSc), a disease in which hands and face are severely affected, leading to disability and a decrease in quality of life. Combining the advantage of an abundant supply of fat tissue and a high abundance of stem/stromal cells, fat grafting and adipose tissue-derived cell-based therapies are attractive therapeutic options in SSc. This review aims to synthesize the evidence to determine the effects of the use of these biological products for face and hands treatment in the context of SSc. This highlights several points: the need to use relevant effectiveness criteria taking into account the clinical heterogeneity of SSc in order to facilitate assessment and comparison of innovative therapies; second, it reveals some impacts of the disease on fat-grafting success; third, an important heterogeneity was noticed regarding the manufacturing of the adipose-derived products and lastly, it shows a lack of robust evidence from controlled trials comparing adipose-derived products with standard care.

Umbilical cord mesenchymal stromal cells—from bench to bedside

In recent years, mesenchymal stromal cells (MSCs) have generated a lot of attention due to their paracrine and immuno-modulatory properties. mesenchymal stromal cells derived from the umbilical cord (UC) are becoming increasingly recognized as having increased therapeutic potential when compared to mesenchymal stromal cells from other sources. The purpose of this review is to provide an overview of the various compartments of umbilical cord tissue from which mesenchymal stromal cells can be isolated, the differences and similarities with respect to their regenerative and immuno-modulatory properties, as well as the single cell transcriptomic profiles of in vitro expanded and freshly isolated umbilical cord-mesenchymal stromal cells. In addition, we discuss the therapeutic potential and biodistribution of umbilical cord-mesenchymal stromal cells following systemic administration while providing an overview of pre-clinical and clinical trials involving umbilical cord-mesenchymal stromal cells and their associated secretome and extracellular vesicles (EVs). The clinical applications of umbilical cord-mesenchymal stromal cells are also discussed, especially in relation to obstacles and potential solutions for their effective translation from bench to bedside.

Cell Secretome Strategies for Controlled Drug Delivery and Wound-Healing Applications

There is significant interest in using stem cells in the management of cutaneous wounds. However, potential safety, efficacy, and cost problems associated with whole-cell transplantation hinder their clinical application. Secretome, a collective of mesenchymal stem-cell-stored paracrine factors, and immunomodulatory cytokines offer therapeutic potential as a cell-free therapy for the treatment of cutaneous wounds. This review explores the possibility of secretome as a treatment for cutaneous wounds and tissue regeneration. The review mainly focuses on in vitro and in vivo investigations that use biomaterials and secretome together to treat wounds, extend secretome retention, and control release to preserve their biological function. The approaches employed for the fabrication of biomaterials with condition media or extracellular vesicles are discussed to identify their future clinical application in wound treatment.

Wharton’s Jelly-Derived Mesenchymal Stem Cells with High Aurora Kinase A Expression Show Improved Proliferation, Migration, and Therapeutic Potential

Mesenchymal stem cells (MSCs) are effective therapeutic agents that contribute to tissue repair and regeneration by secreting various factors. However, donor-dependent variations in MSC proliferation and therapeutic potentials result in variable production yields and clinical outcomes, thereby impeding MSC-based therapies. Hence, selection of MSCs with high proliferation and therapeutic potentials would be important for effective clinical application of MSCs. This study is aimed at identifying the upregulated genes in human Wharton's jelly-derived MSCs (WJ-MSCs) with high proliferation potential using mRNA sequencing. Aurora kinase A (AURKA) and dedicator of cytokinesis 2 (DOCK2) were selected as the upregulated genes, and their effects on proliferation, migration, and colony formation of the WJ-MSCs were verified using small interfering RNA (siRNA) techniques. mRNA expression levels of both the genes were positively correlated with the proliferation capacity of WJ-MSCs. Moreover, AURKA from human WJ-MSCs regulated the antiapoptotic effect of skeletal muscle cells by upregulating the chemokine (C motif) ligand (XCL1); this was further confirmed in the mdx mouse model. Taken together, the results indicated that AURKA and DOCK2 can be used as potential biomarkers for proliferation and migration of human WJ-MSCs. In particular, human WJ-MSCs with high expression of AURKA might have therapeutic efficacy against muscle diseases, such as Duchenne muscular dystrophy (DMD).

LIN28A enhances regenerative capacity of human somatic tissue stem cells via metabolic and mitochondrial reprogramming

Developing methods to improve the regenerative capacity of somatic stem cells (SSCs) is a major challenge in regenerative medicine. Here, we propose the forced expression of LIN28A as a method to modulate cellular metabolism, which in turn enhances self-renewal, differentiation capacities, and engraftment after transplantation of various human SSCs. Mechanistically, in undifferentiated/proliferating SSCs, LIN28A induced metabolic reprogramming from oxidative phosphorylation (OxPhos) to glycolysis by activating PDK1-mediated glycolysis-TCA/OxPhos uncoupling. Mitochondria were also reprogrammed into healthy/fused mitochondria with improved functional capacity. The reprogramming allows SSCs to undergo cell proliferation more extensively with low levels of oxidative and mitochondrial stress. When the PDK1-mediated uncoupling was untethered upon differentiation, LIN28A-SSCs differentiated more efficiently with an increase of OxPhos by utilizing the reprogrammed mitochondria. This study provides mechanistic and practical approaches of utilizing LIN28A and metabolic reprogramming in order to improve SSCs utility in regenerative medicine.

Preclinical assessment of thrombin-preconditioned human Wharton's jelly-derived mesenchymal stem cells for neonatal hypoxic-ischaemic brain injury

Hypoxic-ischaemic encephalopathy (HIE) is a type of brain injury affecting approximately 1 million newborn babies per year worldwide, the only treatment for which is therapeutic hypothermia. Thrombin-preconditioned mesenchymal stem cells (MSCs) exert neuroprotective effects by enriching cargo contents and boosting exosome biogenesis, thus showing promise as a new therapeutic strategy for HIE. This study was conducted to evaluate the tissue distribution and potential toxicity of thrombin-preconditioned human Wharton's jelly-derived mesenchymal stem cells (th-hWJMSCs) in animal models before the initiation of clinical trials. We investigated the biodistribution, tumorigenicity and general toxicity of th-hWJMSCs. MSCs were administered the maximum feasible dose (1 × 105 cells/10 µL/head) once, or at lower doses into the cerebral ventricle. To support the clinical use of th-hWJMSCs for treating brain injury, preclinical safety studies were conducted in newborn Sprague-Dawley rats and BALB/c nude mice. In addition, growth parameters were evaluated to assess the impact of th-hWJMSCs on the growth of newborn babies. Our results suggest that th-hWJMSCs are non-toxic and non-tumorigenic in rodent models, survive for up to 7 days in the brain and hold potential for HIE therapy.

XCL1 Aggravates Diabetic Nephropathy-Mediated Renal Glomerular Endothelial Cell Apoptosis and Inflammatory Response via Regulating p53/Nuclear Factor-Kappa B Pathway

BACKGROUND

Glomerular endothelial cell damage plays an important role in the occurrence and development of diabetic nephropathy (DN).

OBJECTIVES

This study aimed to clarify the role of XCL1 in DN-mediated glomerular endothelial cell apoptosis and whether the function was related to the activation of the p53/nuclear factor-kappa B (NF-κB) signaling pathway.

METHODS

Candidate biomarkers were identified by least absolute shrinkage and selection operator (LASSO) regression model analysis. The area under the receiver operating characteristic curve value was calculated and used to evaluate the discriminating ability. Cell viability, apoptosis, and interleukin-1β and tumor necrosis factor-α expression at messenger RNA and protein levels were detected by using the Cell Counting Kit-8, flow cytometry, ELISA, real-time polymerase chain reaction, and Western blotting assays. In vivo studies were conducted in the DN mice.

RESULTS

The LASSO regression model displayed good discriminating performance, with a C-index of 0.803 and good calibration, and high XCL1 expression was identified as the predicting factor for DN in diabetes mellitus patients. XCL1 expression was upregulated in glomeruli of db/db mice, which was closely related to the expression of its receptor (XCR1). XCL1 overexpression played an important role in the apoptosis and inflammatory response of high glucose (HG)-treated human renal glomerular endothelial cells. Meanwhile, the expression of p53 and the levels of inflammatory cytokines were upregulated upon XCL1 overexpression. p53 silencing with its inhibitor blocked the apoptotic response and inflammatory response in XCL1-overexpressed cells exposed to HG. Besides, the XCL1 overexpression-induced downregulation of NF-κB was reversed by pifithrin-α pretreatment.

CONCLUSIONS

Our findings in this work provided the mechanistic insights into the effects of XCL1 on the modulation of DN development, illustrating that XCL1 might serve as an essential prognostic indicator and therapeutic target for DN progression.

Wharton's Jelly-Derived Mesenchymal Stem Cells Reduce Fibrosis in a Mouse Model of Duchenne Muscular Dystrophy by Upregulating microRNA 499

The aim of this study was to evaluate the therapeutic effects and mechanisms of Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) in an animal model of Duchenne muscular dystrophy (DMD). Mdx mice (3-5 months old) were administered five different doses of WJ-MSCs through their tail veins. A week after injection, grip strength measurements, creatine kinase (CK) assays, immunohistochemistry, and western blots were performed for comparison between healthy mice, mdx control mice, and WJ-MSC-injected mdx mice. WJ-MSCs exerted dose-dependent multisystem therapeutic effects in mdx mice, by decreasing CK, recovering normal behavior, regenerating muscle, and reducing apoptosis and fibrosis in skeletal muscle. We also confirmed that miR-499-5p is significantly downregulated in mdx mice, and that intravenous injection of WJ-MSCs enhanced its expression, leading to anti-fibrotic effects via targeting TGFβR 1 and 3. Thus, WJ-MSCs may represent novel allogeneic "off-the-shelf" cellular products for the treatment of DMD and possibly other muscle disorders.

The use of umbilical cord-derived mesenchymal stem cells in patients with muscular dystrophies: Results from compassionate use in real-life settings

Muscular dystrophies are genetically determined progressive diseases with no cause‐related treatment and limited supportive treatment. Although stem cells cannot resolve the underlying genetic conditions, their wide‐ranging therapeutic properties may ameliorate the consequences of the involved mutations (oxidative stress, inflammation, mitochondrial dysfunction, necrosis). In this study, we administered advanced therapy medicinal product containing umbilical cord‐derived mesenchymal stem cells (UC‐MSCs) to 22 patients with muscular dystrophies. Patients received one to five intravenous and/or intrathecal injections per treatment course in up to two courses every 2 months. Four standard doses of 10, 20, 30, or 40 × 10⁶ UC‐MSCs per injection were used; the approximate dose per kilogram was 1 × 10⁶ UC‐MSCs. Muscle strength was measured with a set of CQ Dynamometer computerized force meters (CQ Elektronik System, Czernica, Poland). Statistical analysis of muscle strength in the whole group showed significant improvement in the right upper limb (+4.0 N); left hip straightening (+4.5 N) and adduction (+0.5 N); right hip straightening (+1.0 N), bending (+7.5 N), and adduction (+2.5 N); right knee straightening (+8.5 N); left shoulder revocation (+13.0 N), straightening (+5.5 N), and bending (+6.5 N); right shoulder adduction (+3.0 N), revocation (+10.5 N), and bending (+5 N); and right elbow straightening (+9.5 N); all these differences were statistically significant. In six patients (27.3%) these changes led to improvement in gait analysis or movement scale result. Only one patient experienced transient headache and lower back pain after the last administration. In conclusion, UC‐MSC therapy may be considered as a therapeutic option for these patients.

An autopsied case of ADSSL1 myopathy

ADSSL1 myopathy is an inherited myopathy with limb weakness, respiratory muscle paralysis, dysphagia, and myocardial symptoms. We present an autopsy case of a 66-year-old male carrying compound heterozygous variants c.781G>A (p.D261N) and c.919delA (p.I307fs) in ADSSL1. He had not run fast since school with no family history. He showed a gradual progression of limb weakness and developed dyspnoea, dysphagia, and Brugada syndrome at the age of 56. The magnetic resonance imaging (MRI) revealed bright tongue sign. Muscle biopsy showed only chronic myopathic changes. He died of respiratory muscle weakness at the age of 66. Autopsy revealed that there were many fibres with vacuoles and nemaline rods in the biceps brachii, tongue, diaphragm, and iliopsoas. Many lipopigments and nuclear clumps were also detected. The myocardium and central nervous system had only nonspecific age-related changes. This is the first autopsied case to clarify the terminal state of ADSSL1 myopathy.

Valproic acid stimulates myogenesis in pluripotent stem cell-derived mesodermal progenitors in a NOTCH-dependent manner

Muscular dystrophies are debilitating neuromuscular disorders for which no cure exists. As this disorder affects both cardiac and skeletal muscle, patients would benefit from a cellular therapy that can simultaneously regenerate both tissues. The current protocol to derive bipotent mesodermal progenitors which can differentiate into cardiac and skeletal muscle relies on the spontaneous formation of embryoid bodies, thereby hampering further clinical translation. Additionally, as skeletal muscle is the largest organ in the human body, a high myogenic potential is necessary for successful regeneration. Here, we have optimized a protocol to generate chemically defined human induced pluripotent stem cell-derived mesodermal progenitors (cdMiPs). We demonstrate that these cells contribute to myotube formation and differentiate into cardiomyocytes, both in vitro and in vivo. Furthermore, the addition of valproic acid, a clinically approved small molecule, increases the potential of the cdMiPs to contribute to myotube formation that can be prevented by NOTCH signaling inhibitors. Moreover, valproic acid pre-treated cdMiPs injected in dystrophic muscles increase physical strength and ameliorate the functional performances of transplanted mice. Taken together, these results constitute a novel approach to generate mesodermal progenitors with enhanced myogenic potential using clinically approved reagents.

A Two-Stage Process for Differentiation of Wharton's Jelly-Derived Mesenchymal Stem Cells into Neuronal-like Cells

With no permanent cure for neurodegenerative diseases, the symptoms reappear shortly after the withdrawal of medicines. A better treatment outcome can be expected if the damaged neurons are partly replaced by functional neurons and/or they are repaired using trophic factors. In this regard, safe cell therapy has been considered as a potential alternative to conventional treatment. Here, we have described a two-stage culture process to differentiate Wharton Jelly mesenchymal stem cells (WJ-MSCs) into neuronal-like cells in the presence of various cues involved in neurogenesis. The fate of cells at the end of each stage was analyzed at the morphometric, transcriptional, and translational levels. In the first stage of priming, constitutively, wingless-activated WJ-MSCs crossed the lineage boundary in favor of neuroectodermal lineage, identified by the loss of mesenchymal genes with concomitant expression of neuron-specific markers, like SOX1, PAX6, NTRK1, and NEUROD2. Neuronal-like cells formed in the second stage expressed many mature neuronal proteins like Map2, neurofilament, and Tuj1 and possessed axon hillock-like structures. In conclusion, the differentiation of a large number of neuronal-like cells from nontumorigenic and trophic factors secreting WJ-MSCs promises the development of a therapeutic strategy to treat neurodegenerative diseases.

Mesenchymal Stromal Cells and Their Secretome: New Therapeutic Perspectives for Skeletal Muscle Regeneration

Mesenchymal stromal cells (MSCs) are multipotent cells found in different tissues: bone marrow, peripheral blood, adipose tissues, skeletal muscle, perinatal tissues, and dental pulp. MSCs are able to self-renew and to differentiate into multiple lineages, and they have been extensively used for cell therapy mostly owing to their anti-fibrotic and immunoregulatory properties that have been suggested to be at the basis for their regenerative capability. MSCs exert their effects by releasing a variety of biologically active molecules such as growth factors, chemokines, and cytokines, either as soluble proteins or enclosed in extracellular vesicles (EVs). Analyses of MSC-derived secretome and in particular studies on EVs are attracting great attention from a medical point of view due to their ability to mimic all the therapeutic effects produced by the MSCs (i.e., endogenous tissue repair and regulation of the immune system). MSC-EVs could be advantageous compared with the parental cells because of their specific cargo containing mRNAs, miRNAs, and proteins that can be biologically transferred to recipient cells. MSC-EV storage, transfer, and production are easier; and their administration is also safer than MSC therapy. The skeletal muscle is a very adaptive tissue, but its regenerative potential is altered during acute and chronic conditions. Recent works demonstrate that both MSCs and their secretome are able to help myofiber regeneration enhancing myogenesis and, interestingly, can be manipulated as a novel strategy for therapeutic interventions in muscular diseases like muscular dystrophies or atrophy. In particular, MSC-EVs represent promising candidates for cell free-based muscle regeneration. In this review, we aim to give a complete picture of the therapeutic properties and advantages of MSCs and their products (MSC-derived EVs and secreted factors) relevant for skeletal muscle regeneration in main muscular diseases.

CD146+Mesenchymal stem cells treatment improves vascularization, muscle contraction and VEGF expression, and reduces apoptosis in rat ischemic hind limb

Peripheral arterial disease (PAD) is an increasingly common narrowing of the peripheral arteries that can lead to lower limb ischemia, muscle weakness and gangrene. Surgical vein or arterial grafts could improve PAD, but may not be suitable in elderly patients, prompting research into less invasive approaches. Mesenchymal stem cells (MSCs) have been proposed as potential therapy, but their effectiveness and underlying mechanisms in limb ischemia are unclear. We tested the hypothesis that treatment with naive MSCs (nMSCs) or MSCs expressing CD146 (^CD146+MSCs) could improve vascularity and muscle function in rat model of hind-limb ischemia. Sixteen month old Sprague-Dawley rats were randomly assigned to 4 groups: sham-operated control, ischemia, ischemia + nMSCs and ischemia+^CD146+MSCs. After 4 weeks of respective treatment, rat groups were assessed for ischemic clinical score, Tarlov score, muscle capillary density, TUNEL apoptosis assay, contractile force, and vascular endothelial growth factor (VEGF) mRNA expression. ^CD146+MSCs showed greater CD146 mRNA expression than nMSCs. Treatment with nMSCs or ^CD146+MSCs improved clinical and Tarlov scores, muscle capillary density, contractile force and VEGF mRNA expression in ischemic limbs as compared to non-treated ischemia group. The improvements in muscle vascularity and function were particularly greater in ischemia+^CD146+MSCs than ischemia + nMSCs group. TUNEL positive apoptotic cells were least abundant in ischemia+^CD146+MSCs compared with ischemia + nMSCs and non-treated ischemia groups. Thus, MSCs particularly those expressing CD146 improve vascularity, muscle function and VEGF expression and reduce apoptosis in rat ischemic limb, and could represent a promising approach to improve angiogenesis and muscle function in PAD.

Exposure of Mesenchymal Stem Cells to an Alzheimer's Disease Environment Enhances Therapeutic Effects

Mesenchymal stem cells (MSCs) have emerged as a promising tool for the treatment of Alzheimer's disease (AD). Previous studies suggested that the coculture of human MSCs with AD in an in vitro model reduced the expression of amyloid-beta 42 (Aβ42) in the medium as well as the overexpression of amyloid-beta- (Aβ-) degrading enzymes such as neprilysin (NEP). We focused on the role of primed MSCs (human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) exposed to an AD cell line via a coculture system) in reducing the levels of Aβ and inhibiting cell death. We demonstrated that mouse groups treated with naïve MSCs and primed MSCs showed significant reductions in cell death, ubiquitin conjugate levels, and Aβ levels, but the effects were greater in primed MSCs. Also, mRNA sequencing data analysis indicated that high levels of TGF-β induced primed-MSCs. Furthermore, treatment with TGF-β reduced Aβ expression in an AD transgenic mouse model. These results highlighted AD environmental preconditioning is a promising strategy to reduce cell death and ubiquitin conjugate levels and maintain the stemness of MSCs. Further, these data suggest that human WJ-MSCs exposed to an AD environment may represent a promising and novel therapy for AD.

A Review on Stem Cell Therapy for Neuropathic Pain

Neuropathic pain is a complex, chronic pain state that is heterogeneous in nature and caused by the consequence of a lesion or disease affecting the somatosensory system. Current medications give a long-lasting pain relief only in a limited percentage of patients also associated with numerous side effects. Stem cell transplantation is one of the attractive therapeutic platforms for the treatment of a variety of diseases, such as neuropathic pain. Here, the authors review the therapeutic effects of stem cell transplantation of different origin and species in different models of neuropathic pain disorders. Stem cell transplantation could alleviate the neuropathic pain; indeed, stem cells are the source of cells, which differentiate into a variety of cell types and lead trophic factors to migrate to the lesion site opposing the effects of damage. In conclusion, this review suggests that stem cell therapy can be a novel approach for the treatment of neuropathic pain.

Fibulin 5, a human Wharton's jelly-derived mesenchymal stem cells-secreted paracrine factor, attenuates peripheral nervous system myelination defects through the Integrin-RAC1 signaling axis

In the peripheral nervous system (PNS), proper development of Schwann cells (SCs) contributing to axonal myelination is critical for neuronal function. Impairments of SCs or neuronal axons give rise to several myelin-related disorders, including dysmyelinating and demyelinating diseases. Pathological mechanisms, however, have been understood at the elementary level and targeted therapeutics has remained undeveloped. Here, we identify Fibulin 5 (FBLN5), an extracellular matrix (ECM) protein, as a key paracrine factor of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) to control the development of SCs. We show that co-culture with WJ-MSCs or treatment of recombinant FBLN5 promotes the proliferation of SCs through ERK activation, whereas FBLN5-depleted WJ-MSCs do not. We further reveal that during myelination of SCs, FBLN5 binds to Integrin and modulates actin remodeling, such as the formation of lamellipodia and filopodia, through RAC1 activity. Finally, we show that FBLN5 effectively restores the myelination defects of SCs in the zebrafish model of Charcot-Marie-Tooth (CMT) type 1, a representative demyelinating disease. Overall, our data propose human WJ-MSCs or FBLN5 protein as a potential treatment for myelin-related diseases, including CMT.

Pressure Stimuli Improve the Proliferation of Wharton's Jelly-Derived Mesenchymal Stem Cells under Hypoxic Culture Conditions

Mesenchymal stem cells (MSCs) are safe, and they have good therapeutic efficacy through their paracrine action. However, long-term culture to produce sufficient MSCs for clinical use can result in side-effects, such as an inevitable senescence and the reduction of the therapeutic efficacy of the MSCs. In order to overcome this, the primary culture conditions of the MSCs can be modified to simulate the stem cells’ niche environment, resulting in accelerated proliferation, the achievement of the target production yield at earlier passages, and the improvement of the therapeutic efficacy. We exposed Wharton’s jelly-derived MSCs (WJ-MSCs) to pressure stimuli during the primary culture step. In order to evaluate the proliferation, stemness, and therapeutic efficacy of WJ-MSCs, image, genetic, and Western blot analyses were carried out. Compared with standard incubation culture conditions, the cell proliferation was significantly improved when the WJ-MSCs were exposed to pressure stimuli. However, the therapeutic efficacy (the promotion of cell proliferation and anti-apoptotic effects) and the stemness of the WJ-MSCs was maintained, regardless of the culture conditions. Exposure to pressure stimuli is a simple and efficient way to improve WJ-MSC proliferation without causing changes in stemness and therapeutic efficacy. In this way, clinical-grade WJ-MSCs can be produced rapidly and used for therapeutic applications.

Anti-Fibrotic Effect of Human Wharton's Jelly-Derived Mesenchymal Stem Cells on Skeletal Muscle Cells, Mediated by Secretion of MMP-1

Extracellular matrix (ECM) components play an important role in maintaining skeletal muscle function, but excessive accumulation of ECM components interferes with skeletal muscle regeneration after injury, eventually inducing fibrosis. Increased oxidative stress level caused by dystrophin deficiency is a key factor in fibrosis in Duchenne muscular dystrophy (DMD) patients. Mesenchymal stem cells (MSCs) are considered a promising therapeutic agent for various diseases involving fibrosis. In particular, the paracrine factors secreted by MSCs play an important role in the therapeutic effects of MSCs. In this study, we investigated the effects of MSCs on skeletal muscle fibrosis. In 2–5-month-old mdx mice intravenously injected with 1 × 10⁵ Wharton’s jelly (WJ)-derived MSCs (WJ-MSCs), fibrosis intensity and accumulation of calcium/necrotic fibers were significantly decreased. To elucidate the mechanism of this effect, we verified the effect of WJ-MSCs in a hydrogen peroxide-induced fibrosis myotubes model. In addition, we demonstrated that matrix metalloproteinase-1 (MMP-1), a paracrine factor, is critical for this anti-fibrotic effect of WJ-MSCs. These findings demonstrate that WJ-MSCs exert anti-fibrotic effects against skeletal muscle fibrosis, primarily via MMP-1, indicating a novel target for the treatment of muscle diseases, such as DMD.

Mesenchymal stromal cell therapies: immunomodulatory properties and clinical progress

Mesenchymal stromal cells (MSCs) are a subset of heterogeneous non-hematopoietic fibroblast-like cells that can differentiate into cells of multiple lineages, such as chondrocytes, osteoblasts, adipocytes, myoblasts, and others. These multipotent MSCs can be found in nearly all tissues but mostly located in perivascular niches, playing a significant role in tissue repair and regeneration. Additionally, MSCs interact with immune cells both in innate and adaptive immune systems, modulating immune responses and enabling immunosuppression and tolerance induction. Understanding the biology of MSCs and their roles in clinical treatment is crucial for developing MSC-based cellular therapy for a variety of pathological conditions. Here, we review the progress in the study on the mechanisms underlying the immunomodulatory and regenerative effects of MSCs; update the medical translation of MSCs, focusing on the registration trials leading to regulatory approvals; and discuss how to improve therapeutic efficacy and safety of MSC applications for future.

Mechanisms underlying the protective effects of mesenchymal stem cell-based therapy

Mesenchymal stem cells (MSCs) have been extensively investigated for the treatment of various diseases. The therapeutic potential of MSCs is attributed to complex cellular and molecular mechanisms of action including differentiation into multiple cell lineages and regulation of immune responses via immunomodulation. The plasticity of MSCs in immunomodulation allow these cells to exert different immune effects depending on different diseases. Understanding the biology of MSCs and their role in treatment is critical to determine their potential for various therapeutic applications and for the development of MSC-based regenerative medicine. This review summarizes the recent progress of particular mechanisms underlying the tissue regenerative properties and immunomodulatory effects of MSCs. We focused on discussing the functional roles of paracrine activities, direct cell-cell contact, mitochondrial transfer, and extracellular vesicles related to MSC-mediated effects on immune cell responses, cell survival, and regeneration. This will provide an overview of the current research on the rapid development of MSC-based therapies.

Regenerative potential of Wharton's jelly-derived mesenchymal stem cells: A new horizon of stem cell therapy

Umbilical cord Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) have recently gained considerable attention in the field of regenerative medicine. Their high proliferation rate, differentiation ability into various cell lineages, easy collection procedure, immuno-privileged status, nontumorigenic properties along with minor ethical issues make them an ideal approach for tissue repair. Besides, the number of WJ-MSCs in the umbilical cord samples is high as compared to other sources. Because of these properties, WJ-MSCs have rapidly advanced into clinical trials for the treatment of a wide range of disorders. Therefore, this paper summarized the current preclinical and clinical studies performed to investigate the regenerative potential of WJ-MSCs in neural, myocardial, skin, liver, kidney, cartilage, bone, muscle, and other tissue injuries.

The secretome of human dental pulp stem cells protects myoblasts from hypoxia‑induced injury via the Wnt/β‑catenin pathway

Human dental pulp stem cells (hDPSCs) present several advantages, including their ability to be non-invasively harvested without ethical concern. The secretome of hDPSCs can promote the functional recovery of various tissue injuries. However, the protective effects on hypoxia-induced skeletal muscle injury remain to be explored. The present study demonstrated that C2C12 myoblast coculture with hDPSCs attenuated CoCl₂-induced hypoxic injury compared with C2C12 alone. The hDPSC secretome increased cell viability and differentiation and decreased G2/M cell cycle arrest under hypoxic conditions. These results were further verified using hDPSC-conditioned medium (hDPSC-CM). The present data revealed that the protective effects of hDPSC-CM depend on the concentration ratio of the CM. In terms of the underlying molecular mechanism, hDPSC-CM activated the Wnt/β-catenin pathway, which increased the protein levels of Wnt1, phosphorylated-glycogen synthase kinase-3β and β-catenin and the mRNA levels of Wnt target genes. By contrast, an inhibitor (XAV939) of Wnt/β-catenin diminished the protective effects of hDPSC-CM. Taken together, the findings of the present study demonstrated that the hDPSC secretome alleviated the hypoxia-induced myoblast injury potentially through regulating the Wnt/β-catenin pathway. These findings may provide new insight into a therapeutic alternative using the hDPSC secretome in skeletal muscle hypoxia-related diseases.

Effects of statins on the biological features of mesenchymal stem cells and therapeutic implications

Statins are well-known lipid-lowering drugs. The pleiotropic effects of statins have brought about some beneficial effects on improving the therapeutic outcomes of cell therapy and tissue engineering approaches. In this review, the impact of statins on mesenchymal stem cell behaviors including differentiation, apoptosis, proliferation, migration, and angiogenesis, as well as molecular pathways which are responsible for such phenomena, are discussed. A better understanding of pathways and mechanisms of statin-mediated effects on mesenchymal stem cells will pave the way for the expansion of statin applications. Furthermore, since designing a suitable carrier for statins is required to maintain a sufficient dose of active statins at the desired site of the body, different systems for local delivery of statins are also reviewed.

Diepoxybutane induces the expression of a novel p53-target gene XCL1 that mediates apoptosis in exposed human lymphoblasts

Diepoxybutane (DEB) is the most potent active metabolite of the environmental chemical 1,3-butadiene (BD). BD is a human carcinogen that exhibits multiorgan systems toxicity. Our previous studies demonstrated that the X-C motif chemokine ligand 1 (XCL1) gene expression was upregulated 3.3-fold in a p53-dependent manner in TK6 lymphoblasts undergoing DEB-induced apoptosis. The tumor-suppressor p53 protein is a transcription factor that regulates a wide variety of cellular processes, including apoptosis, through its various target genes. Thus, the objective of this study was to determine whether XCL1 is a novel direct p53 transcriptional target gene and deduce its role in DEB-induced toxicity in human lymphoblasts. We utilized the bioinformatics tool p53scan to search for known p53 consensus sequences within the XCL1 promoter region. The XCL1 gene promoter region was found to contain the p53 consensus sequences 5'-AGACATGCCTAGACATGCCT-3' at three positions relative to the transcription start site (TSS). Furthermore, the XCL1 promoter region was found, through reporter gene assays, to be transactivated at least threefold by wild-type p53 promoter in DEB-exposed human lymphoblasts. Inactivation of the XCL1 promoter p53-binding motif located at -2.579 kb relative to TSS reduced the transactivation function of p53 on this promoter in DEB-exposed cells by 97%. Finally, knockdown of XCL1 messenger RNA with specific small interfering RNA inhibited DEB-induced apoptosis in human lymphoblasts by 50%. These observations demonstrate, for the first time, that XCL1 is a novel DEB-induced direct p53 transcriptional target gene that mediates apoptosis in DEB-exposed human lymphoblasts.

The systemic exercise-released chemokine lymphotactin/XCL1 modulates in vitro adult hippocampal precursor cell proliferation and neuronal differentiation

Physical exercise has well-established anti-inflammatory effects, with neuro-immunological crosstalk being proposed as a mechanism underlying the beneficial effects of exercise on brain health. Here, we used physical exercise, a strong positive modulator of adult hippocampal neurogenesis, as a model to identify immune molecules that are secreted into the blood stream, which could potentially mediate this process. Proteomic profiling of mouse plasma showed that levels of the chemokine lymphotactin (XCL1) were elevated after four days of running. We found that XCL1 treatment of primary cells isolated from both the dentate gyrus and the subventricular zone of the adult mice led to an increase in the number of neurospheres and neuronal differentiation in neurospheres derived from the dentate gyrus. In contrast, primary dentate gyrus cells isolated from XCL1 knockout mice formed fewer neurospheres and exhibited a reduced neuronal differentiation potential. XCL1 supplementation in a dentate gyrus-derived neural precursor cell line promoted neuronal differentiation and resulted in lower cell motility and a reduced number of cells in the S phase of the cell cycle. This work suggests an additional function of the chemokine XCL1 in the brain and underpins the complexity of neuro-immune interactions that contribute to the regulation of adult hippocampal neurogenesis.

FGF-17 from Hypoxic Human Wharton's Jelly-Derived Mesenchymal Stem Cells Is Responsible for Maintenance of Cell Proliferation at Late Passages

Background and Objectives

Although it is well known that hypoxic culture conditions enhance proliferation of human mesenchymal stem cells, the exact mechanism is not fully understood. In this study, we investigated the effect of fibroblast growth factor (FGF)-17 from hypoxic human Wharton's Jelly-derived mesenchymal stem cells (hWJ-MSCs) on cell proliferation at late passages.

Methods and Results

hWJ-MSCs were cultured in α-MEM medium supplemented with 10% fetal bovine serum (FBS) in normoxic (21% O₂) and hypoxic (1% O₂) conditions. Protein antibody array was performed to analyze secretory proteins in conditioned medium from normoxic and hypoxic hWJ-MSCs at passage 10. Cell proliferation of hypoxic hWJ-MSCs was increased compared with normoxic hWJ-MSCs from passage 7 to 10, and expression of secretory FGF-17 was highly increased in conditioned medium from hypoxic hWJ-MSCs at passage 10. Knockdown of FGF-17 in hypoxic and normoxic hWJ-MSCs decreased cell proliferation, whereas treatment of hypoxic and normoxic hWJ-MSCs with recombinant protein FGF-17 increased their proliferation. Signal transduction of FGF-17 in hypoxic and normoxic hWJ-MSCs involved the ERK1/2 pathway. Cell phenotypes were not changed under either condition. Differentiation-related genes adiponectin, Runx2, and chondroadherin were downregulated in normoxic hWJ-MSCs treated with rFGF-17, and upregulated by siFGF-17. Expression of alkaline phosphatase (ALP), Runx2, and chondroadherin was upregulated in hypoxic hWJ-MSCs, and this effect was rescued by transfection with siFGF-17. Only chondroadherin was upregulated in hypoxic hWJ-MSCs with rFGF-17.

Conclusions

In hypoxic culture conditions, FGF-17 from hypoxic hWJ-MSCs contributes to the maintenance of high proliferation at late passages through the ERK1/2 pathway.

Thrombin Preconditioning Enhances Therapeutic Efficacy of Human Wharton's Jelly-Derived Mesenchymal Stem Cells in Severe Neonatal Hypoxic Ischemic Encephalopathy

We investigated whether thrombin preconditioning of human Wharton's jelly-derived mesenchymal stem cells (MSCs) improves paracrine potency and thus the therapeutic efficacy of naïve MSCs against severe hypoxic ischemic encephalopathy (HIE). Thrombin preconditioning significantly enhances the neuroprotective anti-oxidative, anti-apoptotic, and anti-cytotoxic effects of naïve MSCs against oxygen-glucose deprivation (OGD) of cortical neurons in vitro. Severe HIE was induced in vivo using unilateral carotid artery ligation and hypoxia for 2 h and confirmed using brain magnetic resonance imaging (MRI) involving >40% of ipsilateral hemisphere at postnatal day (P) 7 in newborn rats. Delayed intraventricular transplantation of 1 × 105 thrombin preconditioned but not naïve MSCs at 24 h after hypothermia significantly enhanced observed anti-inflammatory, anti-astroglial, and anti-apoptotic effects and the ensuing brain infarction; behavioral tests, such as cylinder rearing and negative geotaxis tests, were conducted at P42. In summary, thrombin preconditioning of human Wharton's jelly-derived MSCs significantly boosted the neuroprotective effects of naïve MSCs against OGD in vitro by enhancing their anti-oxidative, anti-apoptotic, and anti-cytotoxic effects, and significantly attenuated the severe HIE-induced brain infarction and improved behavioral function tests in vivo by maximizing their paracrine anti-inflammatory, anti-astroglial, and anti-apoptotic effects.

Changes in the liver transcriptome of farmed Atlantic salmon (Salmo salar) fed experimental diets based on terrestrial alternatives to fish meal and fish oil

Background

Dependence on marine natural resources threatens the sustainability of Atlantic salmon aquaculture. In the present study, Atlantic salmon fed for 14 weeks with an experimental diet based on animal by-products and vegetable oil (ABP) exhibited reduced growth performance compared with others fed a fish meal/fish oil based experimental diet (MAR) and a plant protein/vegetable oil-based experimental diet (VEG). To characterize the molecular changes underlying the differences in growth performance, we conducted a 44 K microarray study of the liver transcriptome of the three dietary groups.

Results

The microarray experiment identified 122 differentially expressed features (Rank Products, PFP < 10%). Based on their associated Gene Ontology terms, 46 probes were classified as metabolic and growth-relevant genes, 25 as immune-related, and 12 as related to oxidation-reduction processes. The microarray results were validated by qPCR analysis of 29 microarray-identified transcripts. Diets significantly modulated the transcription of genes involved in carbohydrate metabolism (gck and pfkfb4), cell growth and proliferation (sgk2 and htra1), apoptosis (gadd45b), lipid metabolism (fabp3, idi1, sqs), and immunity (igd, mx, ifit5, and mhcI). Hierarchical clustering and linear correlation analyses were performed to find gene expression patterns among the qPCR-analyzed transcripts, and connections between them and muscle and liver lipid composition. Overall, our results indicate that changes in the liver transcriptome and tissue lipid composition were driven by cholesterol synthesis up-regulation by ABP and VEG diets, and the lower carbohydrate intake in the ABP group. Two of the microarray-identified genes (sgk2 and htra1) might be key to explaining glucose metabolism regulation and the dietary-modulation of the immune system in fish. To evaluate the potential of these genes as predictive biomarkers, we subjected the qPCR data to a stepwise discriminant analysis. Three sets of no more than four genes were found to be able to predict, with high accuracy (67–94%), salmon growth and fatty acid composition.

Conclusions

This study provides new findings on the impact of terrestrial animal and plant products on the nutrition and health of farmed Atlantic salmon, and a new method based on gene biomarkers for potentially predicting desired phenotypes, which could help formulate superior feeds for the Atlantic salmon aquaculture industry.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-5188-6) contains supplementary material, which is available to authorized users.

Efficacy of stem cell therapy in ambulatory and nonambulatory children with Duchenne muscular dystrophy - Phase I-II

Purpose

Duchenne muscular dystrophy (DMD) is an X-linked recessive pediatric disorder that ultimately leads to progressive muscle degeneration. It has been known that cell-based therapies were used to promote muscle regeneration. The main purpose of this study was to investigate the effects of allogeneic Wharton jelly-derived mesenchymal stem cells therapy in Duchenne muscular dystrophy.

Patients and methods

Four ambulatory and five nonambulatory male patients were assessed as having acceptance criteria. Gene expression and immunohistochemical analysis were performed for dystrophin gene expression. The fluorescent in situ hybridization method was used for detection of chimerism and donor–recipient compatibility. Complement dependent lymphocytotoxic crossmatch test and detection of panel reactive antigen were performed. All patients were treated with 2 × 10⁶ cells/kg dose of allogeneic Wharton jelly-derived mesenchymal stem cells via intra-arterial and intramuscular administration. Stability was maintained in patient follow-up tests, which are respiratory capacity tests, cardiac measurements, and muscle strength tests.

Results

The vastus intermedius muscle was observed in one patient with MRI. Chimerism was detected by fluorescent in situ hybridization and mean gene expression was increased to 3.3-fold. An increase in muscle strength measurements and pulmonary function tests was detected. Additionally, we observed two of nine patients with positive panel reactive antigen result.

Conclusion

All our procedures are well tolerated, and we have not seen any application-related complications so far. Our main purpose of this study was to investigate the effects of allogeneic mesenchymal stem cell therapy and determine its suitability and safety as a form of treatment in this untreatable disorder.

Evaluation of platelet lysate as a substitute for FBS in explant and enzymatic isolation methods of human umbilical cord MSCs

Mesenchymal stem cells (MSCs) have immense potential for cell-based therapy of acute and chronic pathological conditions. MSC transplantation for cell-based therapy requires a substantial number of cells in the range of 0.5–2.5 × 10⁶ cells/kg body weight of an individual. A prolific source of MSCs followed by in vitro propagation is therefore an absolute prerequisite for clinical applications. Umbilical cord tissue (UCT) is an abundantly available prolific source of MSC that are fetal in nature and have higher potential for ex-vivo expansion. However, the ex-vivo expansion of MSCs using a xenogeneic supplement such as fetal bovine serum (FBS) carries the risk of transmission of zoonotic infections and immunological reactions. We used platelet lysate (PL) as a xeno-free, allogeneic replacement for FBS and compared the biological and functional characteristics of MSC processed and expanded with PL and FBS by explant and enzymatic method. UCT-MSCs expanded using PL displayed typical immunophenotype, plasticity, immunomodulatory property and chromosomal stability. PL supplementation also showed 2-fold increase in MSC yield from explant culture with improved immunomodulatory activity as compared to enzymatically dissociated cultures. In conclusion, PL from expired platelets is a viable alternative to FBS for generating clinically relevant numbers of MSC from explant cultures over enzymatic method.

Mesenchymal Stromal Cell Therapy for Pancreatitis: A Systematic Review

Background

Based on animal studies, adult mesenchymal stromal cells (MSCs) are promising for the treatment of pancreatitis. However, the best type of this form of cell therapy and its mechanism of action remain unclear.

Methods

We searched the PubMed, Web of Science, Scopus, Google Scholar, and Clinical Trials.gov websites for studies using MSCs as a therapy for both acute and chronic pancreatitis published until September 2017.

Results

We identified 276 publications; of these publications, 18 met our inclusion criteria. In animal studies, stem cell therapy was applied more frequently for acute pancreatitis than for chronic pancreatitis. No clinical trials were identified. MSC therapy ameliorated pancreatic inflammation in acute pancreatitis and pancreatic fibrosis in chronic pancreatitis. Bone marrow and umbilical cord MSCs were the most frequently administered cell types. Due to the substantial heterogeneity among the studies regarding the type, source, and dose of MSCs used, conducting a meta-analysis was not feasible to determine the best type of MSCs.

Conclusion

The available data were insufficient for determining the best type of MSCs for the treatment of acute or chronic pancreatitis; therefore, clinical trials investigating the use of MSCs as therapy for pancreatitis are not warranted.

Pigment epithelium-derived factor from ARPE19 promotes proliferation and inhibits apoptosis of human umbilical mesenchymal stem cells in serum-free medium

Clinical expansion of mesenchymal stem cells (MSCs) is hampered by the lack of knowledge regarding how to prevent MSC apoptosis and promote their proliferation in serum-free medium. Our in vitro studies demonstrated that human umbilical cord MSCs (HUCMSCs) underwent apoptosis in the serum-free medium. When HUCMSCs were co-cultured with retinal pigment epithelial cells (ARPE19), however, HUCMSCs exhibited normal growth and morphology in serum-free medium. Their colony formation was promoted by the conditioned medium (CM) of ARPE19 cells on Matrigel. Proteomics analysis showed that pigment epithelium-derived factor (PEDF) was one of the most abundant extracellular proteins in the ARPE19 CM, whereas enzyme-linked immunosorbent assay confirmed that large amounts of PEDF was secreted from ARPE19 cells. Adding anti-PEDF-blocking antibodies to the co-culture of HUCMSCs with ARPE19 cells increased apoptosis of HUCMSCs. Conversely, treatment with PEDF significantly reduced apoptosis and increased proliferation of HUCMSCs in serum-free medium. PEDF was further demonstrated to exert this anti-apoptotic effect by inhibiting P53 expression to suppress caspase activation. In vivo studies demonstrated that co-injection of HUCMSCs with ARPE19 cells in immunocompromised NOD-SCID mice also increased survival and decreased apoptosis of HUCMSCs. PEDF also showed no negative effect on the mesoderm differentiation capability of HUCMSCs. In conclusion, this study is the first to demonstrate that PEDF promotes HUCMSC proliferation and protects them from apoptosis by reducing p53 expression in the serum-free medium. This study provides crucial information for clinical-scale expansion of HUCMSCs.

Effect of mesenchymal stem cells on induced skeletal muscle chemodenervation atrophy in adult male albino rats

The present research was conducted to evaluate the effect of bone marrow derived mesenchymal stem cells (BM-MSCs) as a potential therapeutic tool for improvement of skeletal muscle recovery after induced chemodenervation atrophy by repeated local injection of botulinum toxin-A in the right tibialis anterior muscle of adult male albino rats. Forty five adult Wistar male albino rats were classified into control and experimental groups. Experimental group was further subdivided into 3 equal subgroups; induced atrophy, BM-MSCs treated and recovery groups. Biochemical analysis of serum LDH, CK and Real-time PCR for Bcl-2, caspase 3 and caspase 9 was measured. Skeletal muscle sections were stained with H and E, Mallory trichrome, and Immunohistochemical reaction for Bax and CD34. Improvement in the skeletal muscle histological structure was noticed in BM-MSCs treated group, however, in the recovery group, some sections showed apparent transverse striations and others still affected. Immunohistochemical reaction of Bax protein showed strong positive immunoreaction in the cytoplasm of muscle fibers in the induced atrophy group. BM-MSCs treated group showed weak positive reaction while the recovery group showed moderate reaction in the cytoplasm of muscle fibers. Immunohistochemical reaction for CD34 revealed occasional positive CD34 stained cells in the induced atrophy group. In BM-MSCs treated group, multiple positive CD34 stained cells were detected. However, recovery group showed some positive CD34 stained cells at the periphery of the muscle fibers. Marked improvement in the regenerative capacity of skeletal muscles after BM-MSCs therapy. Hence, stem cell therapy provides a new hope for patients suffering from myopathies and severe injuries.