BACKGROUND: Mesenchymal stem cells (MSCs) appear to be a good alternative to Schwann cells in the treatment of peripheral nerve injury. Fetal stem cells, like umbilical cord blood (UCB) and umbilical cord (UC) ...BACKGROUND: Mesenchymal stem cells (MSCs) appear to be a good alternative to Schwann cells in the treatment of peripheral nerve injury. Fetal stem cells, like umbilical cord blood (UCB) and umbilical cord (UC) stem cells, have several advantages over adult stem cells. OBJECTIVE: To assess the effects of UC-derived MSCs (UCMSCs) and UCB-derived MSCs (UCBMSCs) in repair of sciatic nerve defects. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at the laboratory of Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, from July to December 2009. MATERIALS: UCMSCs were provided by the Research Institute of Biotechnology, Dongguk University. UCBMSCs were provided by the Laboratory of Stem Cells and Tumor Biology, College of Veterinary Medicine, Seoul National University. Dulbecco's modified Eagle's medium (DMEM) was purchased from Gibco-BRL, USA. METHODS: Seven-week-old Sprague-Dawley rats were randomly and evenly divided into three groups: DMEM, UCBMSCs, and UCMSCs. A 10-mm defect in the left sciatic nerve was constructed in all rats. DMEM (15 μL) containing 1×10^6 UCBMSCs or UCMSCs was injected into the gap between nerve stumps, with the surrounding epineurium as a natural conduit. For the DMEM group, simple DMEM was injected. MAIN OUTCOME MEASURES: At 7 weeks after sciatic nerve dissection, dorsal root ganglia neurons were labeled by fluorogold retrograde labeling. At 8 weeks, electrophysiology and histomorphometry were performed. At 2, 4, 6, and 8 weeks after surgery, sciatic nerve function was evaluated using gait analysis. RESULTS: The UCBMSCs group and the UCMSCs group exhibited similar sciatic nerve function and electrophysiological indices, which were better than the DMEM group, as measured by gait analysis (P 〈 0.05). Fluorogold retrograde labeling of sciatic nerve revealed that the UCBMSCs group demonstrated a higher number of labeled neurons; however, the differences were not significant. Histomorphometric indices were similar in the UCBMSCs and UCMSCs groups, and total axon counts, particularly axon density (P 〈 0.05), were significantly greater in the UCBMSCs and UCMSCs groups than in the DMEM group. CONCLUSION: Transplanting either UCBMSCs or UCMSCs into axotomized sciatic nerves could accelerate and promote sciatic nerve regeneration over 8 weeks. Both treatments had similar effects on nerve regeneration.展开更多
Cordycepin is an active component of parasitic fungus, Cordyceps militaris, and investigated for its pharmacologic efficacy. Increasing evidence supports the anti-tumoral effects of Cordycepin in various types of huma...Cordycepin is an active component of parasitic fungus, Cordyceps militaris, and investigated for its pharmacologic efficacy. Increasing evidence supports the anti-tumoral effects of Cordycepin in various types of human solid tumors. We sought to determine the effects of Cordycepin on oral squamous cell carcinoma in vitro and in vivo. Two oral squamous cell carcinoma cell lines, KB and HSC3, were used in this study. Cells were treated with Cordycepin or diluent, followed by determinations of proliferation by sulforhodamine method and apoptosis by TUNEL assay in vitro. For in vivo experiments, tumor cells were transplanted into nude mice, followed by treatment with Cordycepin or control diluent. In addition, cells were examined for expression of adenosine receptor isotypes, and tested whether cordycepin-induced effects were mediated through adenosine receptors by combinatorial treatment of cordycepin and antagonists specific to each isotype of adenosine receptors. Two cell lines expressed protein of all types of adenosine receptors stronger than normal oral keratinocytes. Cordycepin showed anti-proliferating effect and apoptotic effect on both cell lines in vitro in a dose dependent manner. However, any adenosine receptors did not reverse the effect of cordycepin. In our in vivo experiments, cordycepin failed to decrease the tumor volume significantly, and failed to induce more apoptosis of tumor cells. Cordycepin has anti-proliferating effect and induces apoptosis not mediated by adenosine receptor on oral squamous cell carcinoma cells in vitro. However, in vivo results suggest that cordycepin in itself has a limited value as a novel chemotherapeutic agent for oral squamous cell carcinoma.展开更多
Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous ...Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous Schwann cells in promoting the regeneration of injured peripheral nerve. To validate this hypothesis, human periodontal ligament stem cells (1 × 106) were injected into the crush-injured left mental nerve in rats. Simultaneously, autologous Schwann cells (1 × 106) and PBS were also injected as controls. Real-time reverse transcriptase polymerase chain reaction showed that at 5 days after injection, mRNA expression of low affinity nerve growth factor receptor was sig-nificantaly increased in the left trigeminal ganglion of rats with mental nerve injury. Sensory tests, histomorphometric evaluation and retrograde labeling demonstrated that at 2 and 4 weeks after in-jection, sensory function was significantly improved, the numbers of retrograde labeled sensory neurons and myelinated axons were significantly increased, and human periodontal ligament stem cells and autologous Schwann cells exhibited similar therapeutic effects. These findings suggest that transplantation of human periodontal ligament stem cells show a potential value in repair of mental nerve injury.展开更多
Previous research has demonstrated that cotransplantation of umbilical cord mesenchymal stem cells (UCMSCs) and Schwann cells (SCs) can repair spinal nerve injury, but few studies have investigated their use in pe...Previous research has demonstrated that cotransplantation of umbilical cord mesenchymal stem cells (UCMSCs) and Schwann cells (SCs) can repair spinal nerve injury, but few studies have investigated their use in peripheral nerve regeneration. In the present study, we cotransplanted UCMSCs and SCs to repair 5-mm left sciatic nerve defects in rats, and compared the effects of UCMSCs + SCs transplantation with UCMSCs or SCs transplantation alone. After UCMSCs + SCs transplantation, nerve conduction velocity of the left sciatic nerve and gait were both improved. Retrograde tracing analysis demonstrated that the mean count of fluorogold-labeled neurons, as well as the mean axon count and axon density, were significantly greater in the left sciatic nerve after UCMSCs + SCs transplantation, compared with UCMSCs or SCs transplantation alone. Improvements in conduction velocity and increased sheath thickness in the left sciatic nerve were similar after UCMSCs transplantation and UCMSCs + SCs transplantation. These findings suggest that UCMSCs transplantation can promote the repair of sciatic nerve defects to some extent, but that combined UCMSCs + SCs transplantation has a significantly greater regenerative effect.展开更多
Enhancing Schwann cell proliferation may be beneficial for peripheral nerve repair and nerve regeneration. A traditional herbal formula composed of Fuling (poria cocos), Baizhu (Atractylodes macrocephala), and Dan...Enhancing Schwann cell proliferation may be beneficial for peripheral nerve repair and nerve regeneration. A traditional herbal formula composed of Fuling (poria cocos), Baizhu (Atractylodes macrocephala), and Danggui (Angelica sinensis) (FBD) improves neuronal survival and growth, and FBD may promote the secretion of brain-derived neurotrophic factor. However, the mechanism underlying Schwann cell proliferation remains unclear. We tested whether FBD enhanced the proliferation of human Schwann cells. FBD (20 ug/mL) increased Schwann cell viability and survival and increased the number of cells at G2/M and S phases. FBD also increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, with maximum efficacy at 20 ug/mL.展开更多
基金the Korea Health R&D Project Granted by Ministry of Health and Welfare Republic of Korea, No. A080863
文摘BACKGROUND: Mesenchymal stem cells (MSCs) appear to be a good alternative to Schwann cells in the treatment of peripheral nerve injury. Fetal stem cells, like umbilical cord blood (UCB) and umbilical cord (UC) stem cells, have several advantages over adult stem cells. OBJECTIVE: To assess the effects of UC-derived MSCs (UCMSCs) and UCB-derived MSCs (UCBMSCs) in repair of sciatic nerve defects. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at the laboratory of Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, from July to December 2009. MATERIALS: UCMSCs were provided by the Research Institute of Biotechnology, Dongguk University. UCBMSCs were provided by the Laboratory of Stem Cells and Tumor Biology, College of Veterinary Medicine, Seoul National University. Dulbecco's modified Eagle's medium (DMEM) was purchased from Gibco-BRL, USA. METHODS: Seven-week-old Sprague-Dawley rats were randomly and evenly divided into three groups: DMEM, UCBMSCs, and UCMSCs. A 10-mm defect in the left sciatic nerve was constructed in all rats. DMEM (15 μL) containing 1×10^6 UCBMSCs or UCMSCs was injected into the gap between nerve stumps, with the surrounding epineurium as a natural conduit. For the DMEM group, simple DMEM was injected. MAIN OUTCOME MEASURES: At 7 weeks after sciatic nerve dissection, dorsal root ganglia neurons were labeled by fluorogold retrograde labeling. At 8 weeks, electrophysiology and histomorphometry were performed. At 2, 4, 6, and 8 weeks after surgery, sciatic nerve function was evaluated using gait analysis. RESULTS: The UCBMSCs group and the UCMSCs group exhibited similar sciatic nerve function and electrophysiological indices, which were better than the DMEM group, as measured by gait analysis (P 〈 0.05). Fluorogold retrograde labeling of sciatic nerve revealed that the UCBMSCs group demonstrated a higher number of labeled neurons; however, the differences were not significant. Histomorphometric indices were similar in the UCBMSCs and UCMSCs groups, and total axon counts, particularly axon density (P 〈 0.05), were significantly greater in the UCBMSCs and UCMSCs groups than in the DMEM group. CONCLUSION: Transplanting either UCBMSCs or UCMSCs into axotomized sciatic nerves could accelerate and promote sciatic nerve regeneration over 8 weeks. Both treatments had similar effects on nerve regeneration.
文摘Cordycepin is an active component of parasitic fungus, Cordyceps militaris, and investigated for its pharmacologic efficacy. Increasing evidence supports the anti-tumoral effects of Cordycepin in various types of human solid tumors. We sought to determine the effects of Cordycepin on oral squamous cell carcinoma in vitro and in vivo. Two oral squamous cell carcinoma cell lines, KB and HSC3, were used in this study. Cells were treated with Cordycepin or diluent, followed by determinations of proliferation by sulforhodamine method and apoptosis by TUNEL assay in vitro. For in vivo experiments, tumor cells were transplanted into nude mice, followed by treatment with Cordycepin or control diluent. In addition, cells were examined for expression of adenosine receptor isotypes, and tested whether cordycepin-induced effects were mediated through adenosine receptors by combinatorial treatment of cordycepin and antagonists specific to each isotype of adenosine receptors. Two cell lines expressed protein of all types of adenosine receptors stronger than normal oral keratinocytes. Cordycepin showed anti-proliferating effect and apoptotic effect on both cell lines in vitro in a dose dependent manner. However, any adenosine receptors did not reverse the effect of cordycepin. In our in vivo experiments, cordycepin failed to decrease the tumor volume significantly, and failed to induce more apoptosis of tumor cells. Cordycepin has anti-proliferating effect and induces apoptosis not mediated by adenosine receptor on oral squamous cell carcinoma cells in vitro. However, in vivo results suggest that cordycepin in itself has a limited value as a novel chemotherapeutic agent for oral squamous cell carcinoma.
基金supported by a grant of the Korea Healthcare Technology R&D Project,Ministry for Health,Welfare & Family Affairs,Republic of Korea,No.A101578
文摘Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous Schwann cells in promoting the regeneration of injured peripheral nerve. To validate this hypothesis, human periodontal ligament stem cells (1 × 106) were injected into the crush-injured left mental nerve in rats. Simultaneously, autologous Schwann cells (1 × 106) and PBS were also injected as controls. Real-time reverse transcriptase polymerase chain reaction showed that at 5 days after injection, mRNA expression of low affinity nerve growth factor receptor was sig-nificantaly increased in the left trigeminal ganglion of rats with mental nerve injury. Sensory tests, histomorphometric evaluation and retrograde labeling demonstrated that at 2 and 4 weeks after in-jection, sensory function was significantly improved, the numbers of retrograde labeled sensory neurons and myelinated axons were significantly increased, and human periodontal ligament stem cells and autologous Schwann cells exhibited similar therapeutic effects. These findings suggest that transplantation of human periodontal ligament stem cells show a potential value in repair of mental nerve injury.
基金the Korea Healthcare Technol-ogy R&D Project, Ministry for Health, Welfare & Family Affairs, Republic of Korea, No. A101578
文摘Previous research has demonstrated that cotransplantation of umbilical cord mesenchymal stem cells (UCMSCs) and Schwann cells (SCs) can repair spinal nerve injury, but few studies have investigated their use in peripheral nerve regeneration. In the present study, we cotransplanted UCMSCs and SCs to repair 5-mm left sciatic nerve defects in rats, and compared the effects of UCMSCs + SCs transplantation with UCMSCs or SCs transplantation alone. After UCMSCs + SCs transplantation, nerve conduction velocity of the left sciatic nerve and gait were both improved. Retrograde tracing analysis demonstrated that the mean count of fluorogold-labeled neurons, as well as the mean axon count and axon density, were significantly greater in the left sciatic nerve after UCMSCs + SCs transplantation, compared with UCMSCs or SCs transplantation alone. Improvements in conduction velocity and increased sheath thickness in the left sciatic nerve were similar after UCMSCs transplantation and UCMSCs + SCs transplantation. These findings suggest that UCMSCs transplantation can promote the repair of sciatic nerve defects to some extent, but that combined UCMSCs + SCs transplantation has a significantly greater regenerative effect.
基金the Korea Health R&D Project,No.A080863,Granted by Ministry of Health and Welfare,Republic of Korea
文摘Enhancing Schwann cell proliferation may be beneficial for peripheral nerve repair and nerve regeneration. A traditional herbal formula composed of Fuling (poria cocos), Baizhu (Atractylodes macrocephala), and Danggui (Angelica sinensis) (FBD) improves neuronal survival and growth, and FBD may promote the secretion of brain-derived neurotrophic factor. However, the mechanism underlying Schwann cell proliferation remains unclear. We tested whether FBD enhanced the proliferation of human Schwann cells. FBD (20 ug/mL) increased Schwann cell viability and survival and increased the number of cells at G2/M and S phases. FBD also increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, with maximum efficacy at 20 ug/mL.