Intrathecal Injection of Mesenchymal Stromal Cell Cultured on 3D Fiber Ameliorates Multiple Organ Damage in Murine Lupus.

Up to 60% of patients with systemic lupus erythematosus (SLE) experience autonomic symptom. Sympathetic nervous system damage can cause dysfunction of the bone marrow that activates inflammatory cells, potentially causing multiple organ damage. We hypothesized that sympathetic nervous system damage would induce bone marrow dysfunction with multiple organ damage in SLE, and that multiple organ damage could be improved by therapy targeting the nervous system. Here, we showed that damage to autonomic nerves and Schwann cells occurred in the bone marrow and central nervous system of SLE model mice. A neurotoxic drug increased mortality and induced severe neuropathy and multiple organ damage, while a neuroprotective drug prevented multiple organ damage. The administration of bone marrow-derived mesenchymal stromal cells (BMSCs) cultured on a 3-dimensional fiber scaffold improved bone marrow neuropathy, skin lesions, kidney function, and mortality. Our results reveal that bone marrow neuropathy influence multiple organ damage associated with SLE, and improvement of bone marrow neuropathy by intrathecal injection of BMSC may be a target for SLE multiple-organ damage.

Altered regulation of mesenchymal cell senescence in adipose tissue promotes pathological changes associated with diabetic wound healing.

Pathologic diabetic wound healing is caused by sequential and progressive deterioration of hemostasis, inflammation, proliferation, and resolution/remodeling. Cellular senescence promotes wound healing; however, diabetic wounds exhibit low levels of senescent factors and accumulate senescent cells, which impair the healing process. Here we show that the number of p15INK4B + PDGFRα + senescent mesenchymal cells in adipose tissue increases transiently during early phases of wound healing in both non-diabetic mice and humans. Transplantation of adipose tissue from diabetic mice into non-diabetic mice results in impaired wound healing and an altered cellular senescence-associated secretory phenotype (SASP), suggesting that insufficient induction of adipose tissue senescence after injury is a pathological mechanism of diabetic wound healing. These results provide insight into how regulation of senescence in adipose tissue contributes to wound healing and could constitute a basis for developing therapeutic treatment for wound healing impairment in diabetes.

Injectate spread in ultrasound-guided inferior alveolar nerve block: a cadaveric study.

PURPOSE: Ultrasound-guided inferior alveolar nerve block (UGIANB) is a mandibular analgesic procedure in which local anesthetic is injected into the pterygomandibular space (PMS). Several studies have reported the clinical efficacy of UGIANB for mandibular surgeries; however, its effective range has never been investigated. We performed a cadaveric study to investigate the success rate of UGIANB injections and to determine whether injected dye could stain the mandibular nerve (MN) trunk and its branches. METHODS: We performed UGIANB on the bilateral faces of 4 Thiel-embalmed cadavers. A needle was advanced to the PMS under ultrasound guidance and 5 mL of dye was injected. The cadaver was dissected and inspected for the presence of dye in the PMS; the range of dye spread to any of the inferior alveolar nerve (IAN), lingual nerve (LN), buccal nerve (BN), mandibular nerve (MN), auriculotemporal nerve (ATN), or facial nerves; and for the presence of intravascular dye. RESULTS: We performed eight UGIANB procedures on four cadavers. Dye was observed in the PMS in 7/8 injections. Staining was observed in all IAN, LN, and BNs that could be identified at dissection. No MN or auriculotemporal nerves (ATNs) were stained in any injections. No intravascular dye was observed in any injections. CONCLUSIONS: UGIANB can administer anesthetic into the PMS with high accuracy. UGIANB injections reached the IAN, LN, and BNs, but did not reach the MN or ATNs located outside the PMS. The findings of this cadaveric study indicate that UGIANB can provide sufficient analgesia for mandibular surgeries.

Potential effects of mesenchymal stem cell derived extracellular vesicles and exosomal miRNAs in neurological disorders.

Mesenchymal stem cells are multipotent cells that possess anti-inflammatory, anti-apoptotic and immunomodulatory properties. The effects of existing drugs for neurodegenerative disorders such as Alzheimer's disease are limited, thus mesenchymal stem cell therapy has been anticipated as a means of ameliorating neuronal dysfunction. Since mesenchymal stem cells are known to scarcely differentiate into neuronal cells in damaged brain after transplantation, paracrine factors secreted from mesenchymal stem cells have been suggested to exert therapeutic effects. Extracellular vesicles and exosomes are small vesicles released from mesenchymal stem cells that contain various molecules, including proteins, mRNAs and microRNAs. In recent years, administration of exosomes/extracellular vesicles in models of neurological disorders has been shown to improve neuronal dysfunctions, via exosomal transfer into damaged cells. In addition, various microRNAs derived from mesenchymal stem cells that regulate various genes and reduce neuropathological changes in various neurological disorders have been identified. This review summarizes the effects of exosomes/extracellular vesicles and exosomal microRNAs derived from mesenchymal stem cells on models of stroke, subarachnoid and intracerebral hemorrhage, traumatic brain injury, and cognitive impairments, including Alzheimer's disease.

Bone marrow-derived mesenchymal stem cells improve cognitive impairment in an Alzheimer's disease model by increasing the expression of microRNA-146a in hippocampus.

Alzheimer's disease (AD) is characterized by the accumulation of amyloid-ß and tau. We previously reported that administration of bone marrow mesenchymal stem cells (BM-MSCs) ameliorates diabetes-induced cognitive impairment by transferring exosomes derived from these cells into astrocytes. Here, we show that intracerebroventricularly injected BM-MSCs improve cognitive impairment in AD model mice by ameliorating astrocytic inflammation as well as synaptogenesis. Although AD model mice showed an increase in NF-κB in the hippocampus, BM-MSC-treated AD model mice did not show this increase but showed an increase in levels of microRNA (miR)-146a in the hippocampus. Intracerebroventricularly injected BM-MSCs were attached to the choroid plexus in the lateral ventricle, and thus, BM-MSCs may secrete exosomes into the cerebrospinal fluid. In vitro experiments showed that exosomal miR-146a secreted from BM-MSCs was taken up into astrocytes, and an increased level of miR-146a and a decreased level of NF-κB were observed in astrocytes. Astrocytes are key cells for the formation of synapses, and thus, restoration of astrocytic function may have led to synaptogenesis and correction of cognitive impairment. The present study indicates that exosomal transfer of miR-146a is involved in the correction of cognitive impairment in AD model mice.

Exercise enhances skeletal muscle regeneration by promoting senescence in fibro-adipogenic progenitors.

Idiopathic inflammatory myopathies cause progressive muscle weakness and degeneration. Since high-dose glucocorticoids might not lead to full recovery of muscle function, physical exercise is also an important intervention, but some exercises exacerbate chronic inflammation and muscle fibrosis. It is unknown how physical exercise can have both beneficial and detrimental effects in chronic myopathy. Here we show that senescence of fibro-adipogenic progenitors (FAPs) in response to exercise-induced muscle damage is needed to establish a state of regenerative inflammation that induces muscle regeneration. In chronic inflammatory myopathy model mice, exercise does not promote FAP senescence or resistance against tumor necrosis factor-mediated apoptosis. Pro-senescent intervention combining exercise and pharmacological AMPK activation reverses FAP apoptosis resistance and improves muscle function and regeneration. Our results demonstrate that the absence of FAP senescence after exercise leads to muscle degeneration with FAP accumulation. FAP-targeted pro-senescent interventions with exercise and pharmacological AMPK activation may constitute a therapeutic strategy for chronic inflammatory myopathy.

Biomechanical Analysis of Midfoot Instability After Bifurcate Ligament Injury and Ankle Brace Application: A Cadaveric Study.

This cadaveric study investigated the biomechanical characteristics and stabilizing contribution of the bifurcate ligament using a multidirectional loading method and assessed the stabilizing effect of a brace after injury of the ligament. Eight freshly frozen cadaveric feet were tested for forefoot torque in inversion, eversion, adduction, and plantarflexion. Each band of the bifurcate ligament was transected sequentially, and the contribution of each portion of the ligament, as well as the stabilizing effects of the ankle brace, were examined. Stability decreased substantially after calcaneocuboid ligament transection for inversion and adduction loading. Bracing restored some stability, except for the adduction loading direction, for which it had only limited effect. The data indicate that inversion and adduction loading are strongly related to bifurcate ligament injury. The stabilizing effect of the ankle brace may have limited effectiveness for loads under adduction.

An enriched environment prevents cognitive impairment in an Alzheimer's disease model by enhancing the secretion of exosomal microRNA-146a from the choroid plexus.

Alzheimer's disease (AD) is characterized by the extensive deposition of amyloid-ß plaques and neurofibrillary tangles. We previously found that preserved function of astrocytes is associated with cognitively normal subjects with AD pathology. Here we show that an enriched environment (EE) can prevent cognitive impairment in AD model mice by ameliorating astrocytic inflammation and increasing synaptic density in the subiculum area of the hippocampus. In AD model mice treated with an EE, increased levels of microRNA (miR)-146a and down-regulation of NF-κB were observed in the hippocampus. In addition, increased levels of interferon (IFN)-γ were seen in serum from mice exposed to an EE. In vitro, enhanced miR-146a expression was observed in exosomes derived from the choroid plexus (CP) after IFN-γ treatment. In further in vitro experiments, we transfected miR-146a into Aß/lipopolysaccharide-induced inflammatory astrocytes and showed that miR-146a ameliorated astrocytic inflammation by down-regulating tumor necrosis factor receptor-associated factor 6 and NF-κB. The present study indicates that following an EE, exosomal miR-146a derived from the CP cells is a key factor in ameliorating astrocytic inflammation, leading to synaptogenesis and correction of cognitive impairment.

p16INK4A-expressing mesenchymal stromal cells restore the senescence-clearance-regeneration sequence that is impaired in chronic muscle inflammation.

BACKGROUND: The therapeutic benefits of mesenchymal stromal cells (MSCs) include treatment of chronic inflammation. However, given the short-lived engraftment of these cells in vivo, their therapeutic efficacy remains mysterious. Transient induction of cellular senescence contributes to activation of immune cells, which promotes clearance of damaged cells during tissue remodelling. This may occur in tissue-resident mesenchymal progenitor cells during regeneration. Elucidation of the role of senescence in tissue-resident mesenchymal progenitor cells during regeneration would provide insight into the profile of therapeutic MSCs for treatment of chronic inflammatory disease. METHODS: We evaluated multipotent mesenchymal progenitor cells, termed fibro/adipogenic progenitors (FAPs), and immune cells in acute muscle injury (AMI) model mice and mice with myosin-induced experimental autoimmune myositis, a model of chronic inflammatory myopathy (CIM). Human bone marrow MSCs were optimised for the treatment of CIM using placental extract. FINDING: FAPs in AMI transiently expressed p16INK4A on days 1 and 2 after injury and recruited phagocytic immune cells, whereas in CIM, p16INK4A expression in FAPs was low. Cellular senescence occurs during the natural maturation of the placenta. Therefore, we used human placental extract to induce p16INK4A expression in therapeutic human bone marrow MSCs in culture. Treatment of CIM with p16INK4A-expressing MSCs promoted tissue remodelling by transiently increasing the abundance of engrafted MSCs, inducing cellular senescence in innate FAPs, and recruiting phagocytic immune cells. INTERPRETATION: MSCs may exert their effect by remodelling the chronic inflammatory environment via senescence-related regenerative processes.

Phosphorylated Platelet-Derived Growth Factor Receptor-Positive Cells With Anti-apoptotic Properties Accumulate in the Synovium of Patients With Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease caused by inflammation of the synovium and characterized by chronic polyarthritis that destroys bone and cartilage. Fibroblast-like synoviocytes (FLSs) in the synovium of patients with RA can promote cartilage and bone destruction by producing proteins such as matrix metalloproteinases and receptor activator of NF-κB ligand, thereby representing an important therapeutic target for RA. FLSs have several phenotypes depending on which cell surface proteins and adhesion factors are expressed. Identifying the cellular functions associated with different phenotypes and methods of controlling them are considered essential for developing therapeutic strategies for RA. In this study, synovial tissue was collected from patients with RA and control subjects who required surgery due to ligament injury or fracture. Immunohistological analysis was used to investigate the rates of positivity for phosphorylated platelet-derived growth factor receptor-αß (pPDGFRαß) and cadherin-11 (CDH11) expression, and apoptosis-related markers were assessed for each cell phenotype. Next, FLSs were isolated in vitro and stimulated with tumor necrosis factor-α (TNF-α) in addition to a combination of PDGF and transforming growth factor (2GF) to investigate pPDGFRαß and CDH11 expression and the effects of the inhibition of TNF and cyclin-dependent kinase (CDK) 4/6 on FLSs. Immunohistological analysis showed a large percentage of pPDGFRαß+CDH11- cells in the sub-lining layer (SL) of patients with RA. These cells exhibited increased B-cell lymphoma-2 expression, reduced TNF receptor-1 expression, resistance to cell death, and abnormal proliferation, suggesting a tendency to accumulate in the synovium. Further, in vitro 2GF stimulation of FLSs lowered, whereas 2GF + TNF stimulation increased the pPDGFRαß/CDH11 ratio. Hypothesizing that FLSs stimulated with 2GF + TNF would accumulate in vivo in RA, we determined the therapeutic effects of TNF and CDK4/6 inhibitors. The TNF inhibitor lowered the pPDGFRαß/CDH11 ratio, whereas the CDK4/6 inhibitor suppressed cell proliferation. However, a synergistic effect was not observed by combining both the drugs. We observed an increase in pPDGFRαß+CDH11- cells in the SL of the RA synovium and accumulation of these cells in the synovium. We found that the TNF inhibitor suppressed FLS activity and the CDK4/6 inhibitor reduced cell proliferation.

Mitochondria transfer from mesenchymal stem cells structurally and functionally repairs renal proximal tubular epithelial cells in diabetic nephropathy in vivo.

The underlying therapeutic mechanism of renal tubular epithelium repair of diabetic nephropathy (DN) by bone marrow-derived mesenchymal stem cells (BM-MSCs) has not been fully elucidated. Recently, mitochondria (Mt) transfer was reported as a novel action of BM-MSCs to rescue injured cells. We investigated Mt transfer from systemically administered BM-MSCs to renal proximal tubular epithelial cells (PTECs) in streptozotocin (STZ)-induced diabetic animals. BM-MSCs also transferred their Mt to impaired PTECs when co-cultured in vitro, which suppressed apoptosis of impaired PTECs. Additionally, BM-MSC-derived isolated Mt enhanced the expression of mitochondrial superoxide dismutase 2 and Bcl-2 expression and inhibited reactive oxygen species (ROS) production in vitro. Isolated Mt also inhibited nuclear translocation of PGC-1α and restored the expression of megalin and SGLT2 under high glucose condition (HG) in PTECs. Moreover, isolated Mt directly injected under the renal capsule of STZ rats improved the cellular morphology of STZ-PTECs, and the structure of the tubular basement membrane and brush border in vivo. This study is the first to show Mt transfer from systemically administered BM-MSCs to damaged PTECs in vivo, and the first to investigate mechanisms underlying the potential therapeutic effects of Mt transfer from BM-MSCs in DN.

A Biomechanical Comparison of Single-, Double-, and Triple-Bundle Anterior Cruciate Ligament Reconstructions Using a Hamstring Tendon Graft.

PURPOSE: The first objective of our cadaveric study was to perform a biomechanical comparison of single-bundle (SB), double-bundle (DB), and triple-bundle (TB) anterior cruciate ligament (ACL) reconstructions using a hamstring tendon graft to determine the laxity match pre-tension (LMP) value, which is the tension within the graft required to re-create the same anterior laxity as the ACL-intact knee. The second objective was to determine the anterior laxity and force distribution during the application of both an anterior force and a simulated pivot-shift test. METHODS: Eleven fresh-frozen cadaveric knees were tested using a robotic/universal force-moment sensor system in the intact state, TB-reconstructed knee, DB-reconstructed knee, and SB-reconstructed knee. The LMP in each reconstruction was recorded. Each reconstructed knee was tested with an external load of 100-N anterior drawer and combined rotatory loads of 10-Nm valgus moment and 5-Nm internal rotation. The anterior tibial translation and tensile forces of each graft bundle were measured. RESULTS: The LMP values for the TB reconstruction were 1.7 N for the anteromedial-medial graft, 1.7 N for the anteromedial-lateral graft, and 3.4 N for the posterolateral graft (PLG). The LMP value was 5.6 N for the anteromedial graft and PLG in the DB reconstruction. The LMP value was 26.3 N for the whole graft in the SB reconstruction. No statistically significant difference in stability was found between TB and DB reconstructions during the anterior load and the combined rotatory load test. For force distribution, the PLG tension in the TB reconstruction was statistically lower than that in the DB reconstruction. CONCLUSIONS: Anatomic TB ACL reconstruction with the lowest initial tension on the graft stabilized the knee equally to DB or SB reconstruction, which required greater initial tension. CLINICAL RELEVANCE: Although SB, DB, and TB ACL reconstructions through the anatomic tunnel position could equally restore stability, the initial tension on the graft required to restore stability was less in the latter 2 multi-tunnel reconstructions.

An enriched environment prevents diabetes-induced cognitive impairment in rats by enhancing exosomal miR-146a secretion from endogenous bone marrow-derived mesenchymal stem cells.

Increasing evidence suggests that an enriched environment (EE) ameliorates cognitive impairment by promoting repair of brain damage. However, the mechanisms by which this occurs have not been determined. To address this issue, we investigated whether an EE enhanced the capability of endogenous bone marrow-derived mesenchymal stem/stromal cells (BM-MSCs) to prevent hippocampal damage due to diabetes by focusing on miRNA carried in BM-MSC-derived exosomes. In diabetic streptozotocin (STZ) rats housed in an EE (STZ/EE), cognitive impairment was significantly reduced, and both neuronal and astroglial damage in the hippocampus was alleviated compared with STZ rats housed in conventional cages (STZ/CC). BM-MSCs isolated from STZ/CC rats had functional and morphological abnormalities that were not detected in STZ/EE BM-MSCs. The miR-146a levels in exosomes in conditioned medium of cultured BM-MSCs and serum from STZ/CC rats were decreased compared with non-diabetic rats, and the level was restored in STZ/EE rats. Thus, the data suggest that increased levels of miR-146a in sera were derived from endogenous BM-MSCs in STZ/EE rats. To examine the possibility that increased miR-146a in serum may exert anti-inflammatory effects on astrocytes in diabetic rats, astrocytes transfected with miR-146a were stimulated with advanced glycation end products (AGEs) to mimic diabetic conditions. The expression of IRAK1, NF-κB, and tumor necrosis factor-α was significantly higher in AGE-stimulated astrocytes, and these factors were decreased in miR-146a-transfected astrocytes. These results suggested that EEs stimulate up-regulation of exosomal miR-146a secretion by endogenous BM-MSCs, which exerts anti-inflammatory effects on damaged astrocytes and prevents diabetes-induced cognitive impairment.

ACL Function in Bicruciate-Retaining Total Knee Arthroplasty.

BACKGROUND: Bicruciate-retaining total knee arthroplasty (BCR-TKA) is attracting attention because of the functional and satisfaction outcomes associated with keeping the anterior cruciate ligament (ACL) intact. However, knowledge of the functional importance of the ACL after BCR-TKA is limited. We performed a biomechanical investigation of ACL function following BCR-TKA compared with that in the intact knee. METHODS: We investigated 8 fresh-frozen human cadaveric knees using a 6-degrees-of-freedom robotic system that allowed natural joint motion. Three knee states-intact knee, BCR-TKA, and BCR-TKA with ACL transection (BCR-TKA + ACLT)-were evaluated. For each knee state, the kinematics during passive flexion-extension motion (from 0° to 120°) and anteroposterior laxity at 0°, 15°, 30°, 60°, and 90° of flexion in response to a 100-N load were investigated. The recorded knee motions of the intact and BCR-TKA knees during each test were repeated after ACLT to calculate the ACL in situ force. RESULTS: The femur in the BCR-TKA group translated posteriorly and rotated externally during passive knee flexion and was in an anterior position compared with the femur in the intact-knee state. After ACLT, the femur translated posteriorly, compared with the BCR-TKA group, at 0° and 10° (p < 0.05). The anteroposterior laxities of the BCR-TKA and intact knees were comparable at all flexion angles and increased 2-fold or more after ACLT (p < 0.01). The ACL in situ force in the BCR-TKA knees was 2-fold to 6-fold higher than that in the intact knees at 0°, 15°, 90°, and 120° during a passive path (p < 0.05) and equivalent to that in the intact knees under anterior loading. CONCLUSIONS: The preserved ACL in the BCR-TKA knees was functional, like the ACL in the intact knees, under anterior tibial loading and contributed to good anteroposterior stability. However, the kinematics and ACL in situ force differed between the intact and BCR-TKA knees during passive flexion-extension movements. CLINICAL RELEVANCE: Surgeons may not be able to prevent overtensioning of the ACL during a standardized BCR-TKA procedure, which could potentially limit range of motion.

Effect of Initial Graft Tension During Calcaneofibular Ligament Reconstruction on Ankle Kinematics and Laxity.

BACKGROUND: Although a variety of surgical procedures for lateral ankle ligament reconstruction have frequently been reported, little is known about the effects of initial graft tension. Purpose/Hypothesis: The purpose was to investigate the effects of initial graft tension in calcaneofibular ligament (CFL) reconstruction. It was hypothesized that a high degree of initial graft tension would cause abnormal kinematics, laxity, and excessive graft tension. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve cadaveric ankles were tested with a 6 degrees of freedom robotic system to apply passive plantarflexion-dorsiflexion motion and multidirectional loads. A repeated-measures experiment was designed with the CFL intact, CFL transected, and CFL reconstructed with 4 initial tension conditions (10, 30, 50, and 70 N). The 3-dimensional path and reconstructed graft tension were simultaneously recorded. RESULTS: The calcaneus in CFL reconstruction with an initial tension of 70 N had the most eversion relative to the intact condition (mean eversion translations of 1.2, 3.0, 5.0, and 6.2 mm were observed at initial tensions of 10, 30, 50, and 70 N, respectively). The calcaneus also moved more posteriorly with external rotation as the initial tension increased. The reconstructed graft tension tended to increase as the initial tension increased. CONCLUSION: Ankle kinematic patterns and laxity after CFL reconstruction tended to become more abnormal as the initial graft tension increased at the time of surgery. Moreover, excessive initial graft tension caused excessive tension on the reconstructed graft. CLINICAL RELEVANCE: This study indicated the importance of initial graft tension during CFL reconstruction. Overtensioning during CFL reconstruction should be avoided to imitate a normal ankle.

Umbilical cord extracts improve osteoporotic abnormalities of bone marrow-derived mesenchymal stem cells and promote their therapeutic effects on ovariectomised rats.

Bone marrow-derived mesenchymal stem cells (BM-MSCs) are the most valuable source of autologous cells for transplantation and tissue regeneration to treat osteoporosis. Although BM-MSCs are the primary cells responsible for maintaining bone metabolism and homeostasis, their regenerative ability may be attenuated in postmenopausal osteoporosis patients. Therefore, we first examined potential abnormalities of BM-MSCs in an oestrogen-deficient rat model constructed by ovariectomy (OVX-MSCs). Cell proliferation, mobilisation, and regulation of osteoclasts were downregulated in OVX-MSCs. Moreover, therapeutic effects of OVX-MSCs were decreased in OVX rats. Accordingly, we developed a new activator for BM-MSCs using human umbilical cord extracts, Wharton's jelly extract supernatant (WJS), which improved cell proliferation, mobilisation and suppressive effects on activated osteoclasts in OVX-MSCs. Bone volume, RANK and TRACP expression of osteoclasts, as well as proinflammatory cytokine expression in bone tissues, were ameliorated by OVX-MSCs activated with WJS (OVX-MSCs-WJ) in OVX rats. Fusion and bone resorption activity of osteoclasts were suppressed in macrophage-induced and primary mouse bone marrow cell-induced osteoclasts via suppression of osteoclast-specific genes, such as Nfatc1, Clcn7, Atp6i and Dc-stamp, by co-culture with OVX-MSCs-WJ in vitro. In this study, we developed a new activator, WJS, which improved the functional abnormalities and therapeutic effects of BM-MSCs on postmenopausal osteoporosis.

PDGFR Signaling Mediates Hyperproliferation and Fibrotic Responses of Subsynovial Connective Tissue Cells in Idiopathic Carpal Tunnel Syndrome.

Fibrosis of the subsynovial connective tissue (SSCT) is a pathognomonic change in carpal tunnel syndrome (CTS). Identification of molecular targets and anti-fibrotic therapies could provide new treatment strategies for CTS. The contribution of SSCT cells to fibrosis and the signaling pathways that initiate and aggravate fibrosis in CTS remain unknown. Here we report that platelet-derived growth factor receptor alpha (PDGFRα) positive ( + ) cells accumulate in CTS SSCT and that the presence of fibrotic growth factor, PDGF-AA, results in increased proliferation of PDGFRα+ cells via PI3K/Akt signaling pathway. Although PI3K inhibition decreased proliferation, there was no change in fibrosis-related gene expression. Indeed, protein levels of fibrosis signaling mediator TGF-ß remained the same and the second messenger, Smad2/3, accumulated in the nucleus. In contrast AMP-activated protein kinase (AMPK) activation, which can be induced with metformin and AICAR inhibited proliferation, TGF-ß expression, and altered cell morphology in SSCT cells. Further we show that AMPK activation by metformin reduced collagen III levels and the ratio of Collagen I to Collagen III. Both AICAR and metformin reduced F-actin and significantly reduced the fiber cross alignment. Our results suggest that PDGFRa signaling may be an important fibrosis target and that activators of AMPK, may be an important therapeutic approach for treating CTS.

Umbilical cord extracts improve diabetic abnormalities in bone marrow-derived mesenchymal stem cells and increase their therapeutic effects on diabetic nephropathy.

Bone marrow-derived mesenchymal stem cells (BM-MSC) has been applied as the most valuable source of autologous cell transplantation for various diseases including diabetic complications. However, hyperglycemia may cause abnormalities in intrinsic BM-MSC which might lose sufficient therapeutic effects in diabetic patients. We demonstrated the functional abnormalities in BM-MSC derived from both type 1 and type 2 diabetes models in vitro, which resulted in loss of therapeutic effects in vivo in diabetic nephropathy (DN). Then, we developed a novel method to improve abnormalities in BM-MSC using human umbilical cord extracts, namely Wharton's jelly extract supernatant (WJs). WJs is a cocktail of growth factors, extracellular matrixes and exosomes, which ameliorates proliferative capacity, motility, mitochondrial degeneration, endoplasmic reticular functions and exosome secretions in both type 1 and type 2 diabetes-derived BM-MSC (DM-MSC). Exosomes contained in WJs were a key factor for this activation, which exerted similar effects to complete WJs. DM-MSC activated by WJs ameliorated renal injury in both type 1 and type 2 DN. In this study, we developed a novel activating method using WJs to significantly increase the therapeutic effect of BM-MSC, which may allow effective autologous cell transplantation.