Human induced neural stem cells support functional recovery in spinal cord injury models.

Spinal cord injury (SCI) is a clinical condition that leads to permanent and/or progressive disabilities of sensory, motor, and autonomic functions. Unfortunately, no medical standard of care for SCI exists to reverse the damage. Here, we assessed the effects of induced neural stem cells (iNSCs) directly converted from human urine cells (UCs) in SCI rat models. We successfully generated iNSCs from human UCs, commercial fibroblasts, and patient-derived fibroblasts. These iNSCs expressed various neural stem cell markers and differentiated into diverse neuronal and glial cell types. When transplanted into injured spinal cords, UC-derived iNSCs survived, engrafted, and expressed neuronal and glial markers. Large numbers of axons extended from grafts over long distances, leading to connections between host and graft neurons at 8 weeks post-transplantation with significant improvement of locomotor function. This study suggests that iNSCs have biomedical applications for disease modeling and constitute an alternative transplantation strategy as a personalized cell source for neural regeneration in several spinal cord diseases.

OCT4-induced oligodendrocyte progenitor cells promote remyelination and ameliorate disease.

The generation of human oligodendrocyte progenitor cells (OPCs) may be therapeutically valuable for human demyelinating diseases such as multiple sclerosis. Here, we report the direct reprogramming of human somatic cells into expandable induced OPCs (iOPCs) using a combination of OCT4 and a small molecule cocktail. This method enables generation of A2B5+ (an early marker for OPCs) iOPCs within 2 weeks retaining the ability to differentiate into MBP-positive mature oligodendrocytes. RNA-seq analysis revealed that the transcriptome of O4+ iOPCs was similar to that of O4+ OPCs and ChIP-seq analysis revealed that putative OCT4-binding regions were detected in the regulatory elements of CNS development-related genes. Notably, engrafted iOPCs remyelinated the brains of adult shiverer mice and experimental autoimmune encephalomyelitis mice with MOG-induced 14 weeks after transplantation. In conclusion, our study may contribute to the development of therapeutic approaches for neurological disorders, as well as facilitate the understanding of the molecular mechanisms underlying glial development.

Generation of Induced Nephron Progenitor-like Cells from Human Urine-Derived Cells.

BACKGROUND: Regenerative medicine strategies employing nephron progenitor cells (NPCs) are a viable approach that is worthy of substantial consideration as a promising cell source for kidney diseases. However, the generation of induced nephron progenitor-like cells (iNPCs) from human somatic cells remains a major challenge. Here, we describe a novel method for generating NPCs from human urine-derived cells (UCs) that can undergo long-term expansion in a serum-free condition. RESULTS: Here, we generated iNPCs from human urine-derived cells by forced expression of the transcription factors OCT4, SOX2, KLF4, c-MYC, and SLUG, followed by exposure to a cocktail of defined small molecules. These iNPCs resembled human embryonic stem cell-derived NPCs in terms of their morphology, biological characteristics, differentiation potential, and global gene expression and underwent a long-term expansion in serum-free conditions. CONCLUSION: This study demonstrates that human iNPCs can be readily generated and expanded, which will facilitate their broad applicability in a rapid, efficient, and patient-specific manner, particularly holding the potential as a transplantable cell source for patients with kidney disease.

Glycine decarboxylase regulates the maintenance and induction of pluripotency via metabolic control.

Reprogramming of 'adult' differentiated somatic cells to 'embryonic' pluripotent stem cells accompanied by increased rate of glycolysis. Conversely, glycolysis triggers accumulation of advanced glycation end products (AGEs), a potential causative factor in aging, by promoting methylglyoxal production. Therefore, it is reasonable that pluripotent stem cells (PSCs) would specifically regulate glycolysis to maintain their embryonic features. In this study, we focused on glycine decarboxylase (GLDC), a key enzyme in the glycine cleavage system that regulates glycolysis and methylglyoxal production in cancer. GLDC was exclusively expressed in PSCs, and inhibition of this enzyme induced alterations of metabolome and AGE accumulation, thereby suppressing the embryonic pluripotent state. Surprisingly, the level of accumulated AGEs in somatic cells gradually decreased during reprogramming, ultimately disappearing in iPSCs. In addition, ectopic expression of GLDC or treatment with the AGE inhibitor LR-90 promoted reprogramming. Together, these findings suggest that GLDC-mediated regulation of glycolysis and controlling AGE accumulation is related to maintenance and induction of pluripotency.

Generation of two induced pluripotent stem cell (iPSC) lines from X-linked adrenoleukodystrophy (X-ALD) patients with adrenomyeloneuropathy (AMN).

X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder caused by a mutation in the ATP-binding cassette transporter subfamily D member 1 (ABCD1) gene. We generated two induced pluripotent stem cell (iPSC) lines from X-ALD patients with adrenomyeloneuropathy (AMN) by Sendai virus containing OCT4, SOX2, KLF4 and c-MYC. Established iPSC lines expressed various pluripotency markers, had differentiation potential of three germ layers in vitro, had normal karyotype and retained ABCD1 mutation.

A combination of small molecules directly reprograms mouse fibroblasts into neural stem cells.

The generation of induced neural stem cells (iNSCs) from somatic cells using defined factors provides new avenues for basic research and cell therapies for various neurological diseases, such as Parkinson's disease, Huntington's disease, and spinal cord injuries. However, the transcription factors used for direct reprogramming have the potential to cause unexpected genetic modifications, which limits their potential application in cell therapies. Here, we show that a combination of four chemical compounds resulted in cells directly acquiring a NSC identity; we termed these cells chemically-induced NSCs (ciNSCs). ciNSCs expressed NSC markers (Pax6, PLZF, Nestin, Sox2, and Sox1) and resembled NSCs in terms of their morphology, self-renewal, gene expression profile, and electrophysiological function when differentiated into the neuronal lineage. Moreover, ciNSCs could differentiate into several types of mature neurons (dopaminergic, GABAergic, and cholinergic) as well as astrocytes and oligodendrocytes in vitro. Taken together, our results suggest that stably expandable and functional ciNSCs can be directly reprogrammed from mouse fibroblasts using a combination of small molecules without any genetic manipulation, and will provide a new source of cells for cellular replacement therapy of neurodegenerative diseases.

Conversion of mouse fibroblasts into cardiomyocyte-like cells using small molecule treatments.

The possibility of controlling cell fates by overexpressing specific transcription factors has led to numerous studies in stem cell research. Small molecules can be used, instead of transcription factors, to induce the de-differentiation of somatic cells or to induce pluripotent cells (iPSCs). Here we reported that combinations of small molecules could convert mouse fibroblasts into cardiomyocyte-like cell without requiring transcription factor expression. Treatment with specific combinations of small molecules that are enhancer for iPSC induction converted mouse fibroblasts into spontaneously contracting, cardiac troponin T-positive, cardiomyocyte-like cells. We specifically identified five small molecules that can induce mouse fibroblasts to form these cardiomyocyte-like cells. These cells are similar to primary cardiomyocytes in terms of marker gene expression, epigenetic status of cardiac-specific genes, and subcellular structure. Our findings indicate that lineage conversion can be induced not only by transcription factors, but also by small molecules.

Reprogramming of mouse somatic cells into pluripotent stem-like cells using a combination of small molecules.

Somatic cells can be reprogrammed to generate induced pluripotent stem cells (iPSCs) by overexpression of four transcription factors, Oct4, Klf4, Sox2, and c-Myc. However, exogenous expression of pluripotency factors raised concerns for clinical applications. Here, we show that iPS-like cells (iPSLCs) were generated from mouse somatic cells in two steps with small molecule compounds. In the first step, stable intermediate cells were generated from mouse astrocytes by Bmi1. These cells called induced epiblast stem cell (EpiSC)-like cells (iEpiSCLCs) are similar to EpiSCs in terms of expression of specific markers, epigenetic state, and ability to differentiate into three germ layers. In the second step, treatment with MEK/ERK and GSK3 pathway inhibitors in the presence of leukemia inhibitory factor resulted in conversion of iEpiSCLCs into iPSLCs that were similar to mESCs, suggesting that Bmi1 is sufficient to reprogram astrocytes to partially reprogrammed pluripotency. Next, Bmi1 function was replaced with Shh activators (oxysterol and purmorphamine), which demonstrating that combinations of small molecules can compensate for reprogramming factors and are sufficient to directly reprogram mouse somatic cells into iPSLCs. The chemically induced pluripotent stem cell-like cells (ciPSLCs) showed similar gene expression profiles, epigenetic status, and differentiation potentials to mESCs.

Hypoxic conditioned medium from human amniotic fluid-derived mesenchymal stem cells accelerates skin wound healing through TGF-ß/SMAD2 and PI3K/Akt pathways.

In a previous study, we isolated human amniotic fluid (AF)-derived mesenchymal stem cells (AF-MSCs) and utilized normoxic conditioned medium (AF-MSC-norCM) which has been shown to accelerate cutaneous wound healing. Because hypoxia enhances the wound healing function of mesenchymal stem cell-conditioned medium (MSC-CM), it is interesting to explore the mechanism responsible for the enhancement of wound healing function. In this work, hypoxia not only increased the proliferation of AF-MSCs but also maintained their constitutive characteristics (surface marker expression and differentiation potentials). Notably, more paracrine factors, VEGF and TGF-ß1, were secreted into hypoxic conditioned medium from AF-MSCs (AF-MSC-hypoCM) compared to AF-MSC-norCM. Moreover, AF-MSC-hypoCM enhanced the proliferation and migration of human dermal fibroblasts in vitro, and wound closure in a skin injury model, as compared to AF-MSC-norCM. However, the enhancement of migration of fibroblasts accelerated by AF-MSC-hypoCM was inhibited by SB505124 and LY294002, inhibitors of TGF-ß/SMAD2 and PI3K/AKT, suggesting that AF-MSC-hypoCM-enhanced wound healing is mediated by the activation of TGF-ß/SMAD2 and PI3K/AKT. Therefore, AF-MSC-hypoCM enhances wound healing through the increase of hypoxia-induced paracrine factors via activation of TGF-ß/SMAD2 and PI3K/AKT pathways.

Efficacy of oregonin investigated by non-invasive evaluation in a B16 mouse melanoma model.

Oregonin has been reported to act as a mediator of antibiosis, a liver-protective agent, an antioxidant, an anti-inflammatory agent, and to prevent cancer outbreaks. B16 melanoma cells were separated with trypsin-ethylenediaminetetraacetic acid, resuspended in 50 µl of phosphate-buffered saline and transplanted into the backs of 6- to 8-week-old male Balb/c nude mice through subcutaneous injection. Treatment doses of oregonin were administered three times weekly, for 30 days from the 11th day after transplantation of the melanoma cells, in each group. The study consisted of a control group, a dacarbazine group, an oregonin group and a dacarbazine + oregonin group. Measurements were taken before treatment and on the 5th, 7th, 10th and 15th days after treatment for each group. Based on survival rates after transplantation, the control group showed less than 50% survival after 20 days, while the treatment groups showed at least 50% survival up to the 41st day.

Reprogramming of mouse fibroblasts into induced pluripotent stem cells with Nanog.

Oct4-Sox2-Nanog transcriptional networks are critical for the maintenance of embryonic stem (ES) cell self-renewal and induction of pluripotency. However, in transcription factor-induced reprogramming of somatic cells into induced pluripotent stem cells (iPSCs), Nanog is initially dispensable and Oct4 remains the sole factor that could not be substituted/omitted. Here, we show that mouse fibroblasts could be reprogrammed into iPSCs by Nanog and Bmi1, which replaces Sox2, Klf4, and c-Myc, in the absence of Oct4. Furthermore, we show that in the presence of shh agonists (oxysterol and purmophamine), which replaces the function of Bmi1, a single transcription factor, Nanog is sufficient to reprogram mouse fibroblasts into iPSCs. Nanog-induced iPSCs resemble mESCs in terms of morphology, global gene expression profiles, epigenetic status and pluripotency both in vitro and in vivo. These findings support that Nanog can replace the Oct4 for the somatic cell reprogramming and underlie the mechanisms of Nanog in reprogramming process.

Improved quantitative evaluation of atopic dermatitis by camera calibration and rectification of a stereo image.

BACKGROUND/PURPOSE: The aim of this study was to establish a scientific assessment method to evaluate the severity of atopic dermatitis (AD) by calibrating part of a previously described stereo-image optical topometer (SOT). METHODS: The old SOT was created using a non-convergence model. However, this study utilizes a convergence model. Camera calibration and rectification were performed using images obtained from stereo cameras. We attempted to verify the efficacy of AD treatment by objectively measuring the improvement in a group of subjects. Twenty AD patients with a variety of disease types were divided into a control group and a treatment group. RESULTS: The scoring of the AD (SCORAD) index did not show any improvements in the treated patients. However, when comparing the advanced SOT and the old SOT, we observed a decreased variation for five parameters, indicating that the treated patients experienced improved outcomes compared with controls. Most notably, we found that the coefficient of variation of the advanced SOT was lower than that of the old SOT. CONCLUSION: We conclude that the advanced SOT may be useful for evaluating AD. The use of an advanced stereo image system may yield more reliable results than the old SOT system.

Effect of pedunculagin investigated by non-invasive evaluation on atopic-like dermatitis in NC/Nga mice.

BACKGROUND/PURPOSE: Atopic dermatitis (AD) is a chronic relapsing inflammatory skin disorder that is becoming increasingly prevalent. Experimental animal models have been an indispensable tool for studying its pathological mechanisms and for in vivo testing of novel therapeutic approaches. AD-like lesions can be induced experimentally in NC/Nga mice. Pedunculagin, an ellagitannin purified from the Manchurian alder, Alnus hirsuta var. microphylla, Betulaceae, is a novel immunomodulator. To evaluate the effect of pedunculagin for AD-like lesions in NC/Nga mice, using clinical and non-invasive methods. METHODS: AD-like lesions were induced in NC/Nga mice using 2,4,6-trinitrochlorobenzene (TNCB). A cream containing 0.1% or 0.5% pedunculagin was applied to the positive treatment group, and the base cream without pedunculagin was applied to the negative treatment group. The control group did not receive any kind of topical agents. We evaluated the therapeutic efficacy of pedunculagin for AD by statistical evaluation of the clinical severity score using non-invasive biomedical engineering tools before treatment, and 1 day, 3 days, 1 week, 2 weeks and 4 weeks afterwards. RESULTS: An AD-like skin rash was successfully induced using TNCB in NC/Nga mice. The group receiving higher concentrations of pedunculagin showed faster and greater improvement. CONCLUSION: Our results suggest that remedies made from natural materials like pedunculagin are now showing promise for medical applications, and many new studies are expected to explore this potential.

Optimal suppression of protein phosphatase 2A activity is critical for maintenance of human embryonic stem cell self-renewal.

The self-renewal of embryonic stem cells involves a balance between processes governed by crosstalk between intrinsic and extrinsic factors. We hypothesized that protein serine/threonine phosphatase 2A (PP2A) may play a central role in the signaling pathways that regulate human embryonic stem cell (hESC) self-renewal. Biochemical analyses revealed that PP2A activity gradually increases over the course of hESC differentiation; PP2A/C and PP2A/A levels also increased. The overexpression of PP2A/C or the addition of PP2A activator C2-ceramide promoted hESC differentiation. Accordingly, the addition of PP2A inactivator okadaic acid (OA) maintained hESC self-renewal in the absence of basic fibroblast growth factor (bFGF). The hESCs maintained with OA expressed pluripotency markers and exhibited substantial telomerase activity with normal karyotypes. The hESCs were able to differentiate into derivatives of the three germ layers, both in vitro and in vivo. Furthermore, the addition of OA and bFGF enabled the maintenance of hESC self-renewal without feeder cells, even in chemically defined xeno-free media. These findings shed a light on the role of PP2A in hESC differentiation and provide a novel strategy for maintaining the self-renewal capability of hESC in bFGF-free, feeder cell-free, and xeno-free media through the optimal suppression of PP2A activity using OA.

Isolation and characterization of multipotent human keloid-derived mesenchymal-like stem cells.

In this study, we report the isolation and characterization of a population of multipotent keloid-derived mesenchymal-like stem cells (KMLSCs) from keloid scalp tissues. These KMLSCs expressed the typical mesenchymal stem cell marker proteins CD13, CD29, CD44, CD90, fibronectin, and vimentin when they were cultured in serum-containing medium and when subsequent exposure to various differentiation media resulted in their differentiation into adipocytes, osteoblasts, chondrocytes, smooth muscle cells, and angiogenic endothelial cells. When KMLSCs were cultured in neural stem culture conditions (i.e., in the presence of epidermal growth factor and fibroblast growth factor 2 in substrate-free conditions), they produced large numbers of neurospheres containing nestin-, CD133-, and SOX2-positive cells that expressed neural-crest stem cell markers. Subsequent exposure of these cells to different differentiation conditions resulted in cells that expressed neuronal cell-, astrocyte-, oligodendrocyte-, or Schwann cell-specific markers. Our study suggests that KMLSCs may be an alternative adult stem cell resource for regenerative tissue repair and auto-transplantation.

Green tea polyphenol epigallocatechin-3-gallate suppresses collagen production and proliferation in keloid fibroblasts via inhibition of the STAT3-signaling pathway.

Keloids are benign skin tumors characterized by collagen accumulation and hyperproliferation of fibroblasts. To find an effective therapy for keloids, we explored the pharmacological potential of (-)-epigallocatechin-3-gallate (EGCG), a widely investigated tumor-preventive agent. When applied to normal and keloid fibroblasts (KFs) in vitro, proliferation and migration of KFs were more strongly suppressed by EGCG than normal fibroblast proliferation and migration (IC(50): 54.4 microM (keloid fibroblast (KF)) versus 63.0 microM (NF)). The level of Smad2/3, signal transducer and activator of transcription-3 (STAT3), and p38 phosphorylation is more enhanced in KFs, and EGCG inhibited phosphorylation of phosphatidylinositol-3-kinase (PI3K), extracellular signal-regulated protein kinase 1/2 (ERK1/2), and STAT3 (Tyr705 and Ser727). To evaluate the contribution of these pathways to keloid pathology, we treated KFs with specific inhibitors for PI3K, ERK1/2, or STAT3. Although a PI3K inhibitor significantly suppressed proliferation, PI3K and MEK/ERK inhibitors had a minor effect on migration and collagen production. However, a JAK2/STAT3 inhibitor and a STAT3 siRNA strongly suppressed proliferation, migration, and collagen production by KFs. We also found that treatment with EGCG suppressed growth and collagen production in the in vivo keloid model. This study demonstrates that EGCG suppresses the pathological characteristics of keloids through inhibition of the STAT3-signaling pathway. We propose that EGCG has potential in the treatment and prevention of keloids.

Induction of neural stem cell-like cells (NSCLCs) from mouse astrocytes by Bmi1.

Recently, Bmi1 was shown to control the proliferation and self-renewal of neural stem cells (NSCs). In this study, we demonstrated the induction of NSC-like cells (NSCLCs) from mouse astrocytes by Bmi1 under NSC culture conditions. These NSCLCs exhibited the morphology and growth properties of NSCs, and expressed NSC marker genes, including nestin, CD133, and Sox2. In vitro differentiation of NSCLCs resulted in differentiated cell populations containing astrocytes, neurons, and oligodendrocytes. Following treatment with histone deacetylase inhibitors (trichostatin A and valproic acid), the potential of NSCLCs for proliferation, dedifferentiation, and self-renewal was significantly inhibited. Our data indicate that multipotent NSCLCs can be generated directly from astrocytes by the addition of Bmi1.

WDNM1 is associated with differentiation and apoptosis of mammary epithelial cells.

In this study, we show that expression of the Westmead DMBA8 nonmetastatic cDNA 1 (WDNM1) gene was increased upon SFM and/or TNFalpha treatment, with a corresponding increase in apoptotic cells, and gradually decreased following re-stimulation with serum in HC11 mammary epithelial cells. TNFalpha induced WDNM1 expression showed the NFkappaB-dependent mechanism since it's expression was abrogated in IkappaBalphaM (super-repressor of NFkappaB)-transfected cells, but not those transfected with control vector. Furthermore, overexpression of WDNM1 suppressed growth and differentiation, and accelerated apoptosis of HC11 cells. Thus, our results demonstrate that WDNM1 gene expression, regulated by the TNFalpha-NFkappaB signal pathway, is associated with HC11 cell apoptosis.