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Objective To investigate the efficacy ofpoly (lactic acid co castor oil) microspheres containing ropivacaine for sciatic nerve block of mice.Methods A total of 150 Kunming male mice were randomly assigned into 3 groups,namely placebo microspheres (lactic acid co castor oil) group (group A,n=50),ropivacaine injection group (group B,n=50) and ropivacaine microspheres group (group C,n=50).After sevoflurane anesthesia,the mouse was fixed on the operating table and the bilateral sciatic nerve was exposed.The corresponding preparations were implanted or injected near the sciatic nerve.Five mice were randomly selected from each group for the next experiments.Paw withdrawal thermal latency,the ability to splay and flex of the hind paw and plasma ropivacaine concentration were measured 10min,30min,1h,3h,5h,7h,10h,15h,30h and 48h after drug administration.Results The anesthetic effect of group C began to work at 3h.Compared with group B,the duration of sciatic nerve sensory block of group C was significantly longer and the effect of motor block was weaker.No anesthetic effect was observed in group A.The sensory and motor block of group B reached the peak at 1h,and the pharmacodynamics subsided at 7h.Compared with group B,the concentration of ropivacaine in group C increased slowly,and the peak value at 10h after administration was gradually decreased.Conclusions Ropivacaine loading poly (lactic acid co castor oil) microspheres can significantly extend the effect of ropivacaine on sciatic nerve sensory block.Compared with ropivacaine injection,motor block effect of ropivacaine loading poly (lactic acid co castor oil) microspheres is reduced and its plasma ropivacaine concentration fluctuation range is small.
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Objective To investigate the effects of sphingosine-1-phosphate receptor 1 (S1PR1) changes on the proliferation of endogenous neural stem cells (NSCs) in hippocampus after traumatic brain injury (TBI).Methods Rat TBI models were constructed by the means of controlled cortical injury.A total of 72 rats were included and randomly divided into four groups:sham,TBI,TBI + SEW (TBI + S1PR1 agonist SEW2871 intervention) and TBI + VPC group (TBI + S1PR1 antagonist VPC23019 intervention),with 18 rats per group.The TBI model was induced by a control cortical injury device.The injured rats in TBI + SEW group and TBI + VPC group were respectively administrated with S1PR1 agonist SEW2871 and antagonist VPC23019 at scheduled time points after TBI.Hippocampal S1PR1 expression was detected by Western-blotting and the proliferation of NSCs was assessed by double-labeled immunofluorescence staining at days 7,14 and 21 after injury.Results At days 7,14 and 21 after TBI,the hippocampal S1PR1 levels and NSCs proliferation amounts in sham,TBI,TBI + SEW and TBI + VPC groups were evidently different (P ＜ 0.05).In particular,the outstanding changes among the four groups above occurred at 7 d after injury were as following:S1PR1 expression in TBI group significantly increased by 1.56 times compared with that in sham group,and it was respectively upregulated by 66.67％ in TBI + SEW group and down-regulated by 20.29％ in TBI + VPC group (P ＜0.05).The nmmber of NSCs proliferation in TBI group was 2.08 times more than that in sham group,and it increased by 36.75％ in TBI + SEW group and reduced by 18.77％ in TBI + VPC group (P ＜ 0.05).Conclusion The expression of S1 PRI is closely associated with the proliferation of NSCs in hippocampus after TBI,indicating that S1PR1 activation may be an effective strategy to improve the posttraumatic neurogenesis.
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Objective To investigate the effects of sphingosine-1-phosphate receptor 1 (S1PR1) changes on the proliferation of endogenous neural stem cells (NSCs) in hippocampus after traumatic brain injury (TBI).Methods Rat TBI models were constructed by the means of controlled cortical injury.A total of 72 rats were included and randomly divided into four groups:sham,TBI,TBI + SEW (TBI + S1PR1 agonist SEW2871 intervention) and TBI + VPC group (TBI + S1PR1 antagonist VPC23019 intervention),with 18 rats per group.The TBI model was induced by a control cortical injury device.The injured rats in TBI + SEW group and TBI + VPC group were respectively administrated with S1PR1 agonist SEW2871 and antagonist VPC23019 at scheduled time points after TBI.Hippocampal S1PR1 expression was detected by Western-blotting and the proliferation of NSCs was assessed by double-labeled immunofluorescence staining at days 7,14 and 21 after injury.Results At days 7,14 and 21 after TBI,the hippocampal S1PR1 levels and NSCs proliferation amounts in sham,TBI,TBI + SEW and TBI + VPC groups were evidently different (P ＜ 0.05).In particular,the outstanding changes among the four groups above occurred at 7 d after injury were as following:S1PR1 expression in TBI group significantly increased by 1.56 times compared with that in sham group,and it was respectively upregulated by 66.67％ in TBI + SEW group and down-regulated by 20.29％ in TBI + VPC group (P ＜0.05).The nmmber of NSCs proliferation in TBI group was 2.08 times more than that in sham group,and it increased by 36.75％ in TBI + SEW group and reduced by 18.77％ in TBI + VPC group (P ＜ 0.05).Conclusion The expression of S1 PRI is closely associated with the proliferation of NSCs in hippocampus after TBI,indicating that S1PR1 activation may be an effective strategy to improve the posttraumatic neurogenesis.
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BACKGROUND:Stem cells have been widely used in the treatment of spinal cord injury,but the clinical application is limited by immune rejection,difficulty in cell harvesting and purification.However,human nasal mucosa mesenchymal stem cells (hNM-MSCs) have no such problems,and its clinical application in the treatment of spinal cord injury has been not reported yet.OBJECTIVE:To observe the biological characteristics of autologous hNM-MSCs and its clinical efficacy in the treatment of advanced incomplete spinal cord injury.METHODS:NM-MSCs were isolated from the human nasal mucosa,cultured and identified in vitro.The ultrastructure of NM-MSCs was observed by transmission electron microscope and scanning electron microscope.Then the NM-MSCs were induced to differentiate into osteocytes,adipocytes,stem cell spheres,or neurons in vitro.Totally eight patients with incomplete spinal cord injury were enrolled and subjected to hNM-MSCs transplantation via lumbar puncture for 1-3 sessions of about 5× 107 cells each,with an interval of 5-7 days,after the approval of the medical ethics committee.All the patients were followed up for 6 months.Preoperative and postoperative therapeutic effect evaluations were performed on the basis of American Spinal Injury Association (ASIA) scores.RESULTS AND CONCLUSION:Under light microscope,the NM-MSCs were mainly spindle-shaped,positive for STRO-1 and exhibited a radial arrangement.NM-MSCs highly expressed CD73,CD90 and CD105,but did not express CD34 and CD45,with the purity of over 97％.And lots of podgy microvilli were seen on the surface of NM-MSCs under the scanning electron microscope,and two kinds of cell morphologies were seen under the transmission electron microscope.Moreover,hNM-MSCs had the ability to differentiate into osteocytes,adipocytes,stem cell spheres and neurons.During the 6-month follow-up,seven patients achieved neurological function recovery to different extents except for one patient,and no side effects were found.It is concluded that hNM-MSCs can become the ideal seed cells for tissue-engineered cell repair.Autologous NM-MSCs transplantation for the treatment of spinal cord injury can achieve the ideal effect,with the value of clinical application.
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BACKGROUND: Human olfactory mucosa mesenchymal stem cells (hOM-MSCs) not only have the basic characteristics of mesenchymal stem cells, but also originate from the ectoderm and are prone to differentiate into neurons, which are a kind of ideal seed cells for nerve repair and regeneration. Cells are conventionally cultured in about 21% in vitro, while only 3%-9% oxygen is found in the human body and tissue space. There is still no report on the effect of hypoxia on the proliferation and activity of hOM-MSCs.OBJECTIVE: To explore whether hypoxic microenvironment can promote hOM-MSCs proliferation and activity and the related mechanism. METHODS: hOM-MSCs were isolated, cultured and identified by flow cytometry and immunofluorescence. The passage 4 hOM-MSCs were divided into three groups: 21% O2 group, 3% O2 group and 3% O2+20 μmol/L YC-1 (HIF-1α inhibitors) group. Proliferation and apoptosis of hOM-MSCs was detected by flow cytometry after 72 hours of culture. The proliferating cell nuclear antigen protein expression was detected by western blot. The mRNA and protein expression of HIF-1α and TWIST were detected by Q-PCR and western blot. RESULTS AND CONCLUSION: The purity of hOM-MSCs was up to 97%, as defined by flow cytometry. The proliferation index of 3% O2 group was higher than the 21% O2 group (P < 0.05), and cell survival and apoptosis ratio (apoptotic cells included mechanical death + early apoptosis + late apoptosis) between the two groups had no significant difference (P > 0.05). Western blot results showed that the proliferating cell nuclear antigen protein expression in the 3% O2 group was significantly higher than that in the other groups (P < 0.05). The HIF-1α and TWIST expressions at mRNA and protein levels in the 3% O2 group were significantly higher than those in the other groups (P < 0.05). To conclude, hypoxic microenvironment can promote the hOM-MSCs proliferation and has no effect on the apoptosis, and the HIF-TWIST signal pathway plays an important role in this progress.
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To explore whether hypoxic condition could promote the olfactory mucosa mesenchymal stem cells (OM-MSCs) to differentiate into neurons with the olfactory ensheathing cells (OECs) supernatant and the potential mechanisms. Methods: The OM-MSCs and OECs were isolated and cultured, and they were identified by flow cytometry and immunofluorescence. The OM-MSCs were divided into three groups: a 3%O2+ HIF-1α inhibitors (lificiguat: YC-1) + OECs supernatant group (Group A) , a 3%O2 + OECs supernatant group (Group B) and a 21%O2 + OECs supernatant group (Control group). The neurons, which were differentiated from OM-MSCs, were assessed by immunofluorescence test. The mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α), βIII-tubulin and glial fibrillary acidic portein (GFAP) were detected by quantitative polymerase chain reaction (Q-PCR) and Western blot. The potassium channels were analyzed by patch clamp. Results: The neurons differentiated from OM-MSCs expressed the most amount of βIII-tubulin, and the result of Q-PCR showed that HIF-1α expression in the Group B was significantly higher than that in the other groups (all P<0.05). Western blot result showed that the βIII-tubulin protein expression was significantly higher and GFAP protein expression was obviously decreased in the Group B (both P<0.05). The patch clamp test confirmed that the potassium channels in the neurons were activated. Conclusion: Hypoxic condition can significantly increase the neuronal differentiation of OM-MSCs by the OECs supernatant and decrease the production of neuroglia cells, which is associated with the activation of HIF-1 signal pathway.
Subject(s)
Blotting, Western , Cell Differentiation , Physiology , Cells, Cultured , Culture Media, Conditioned , Chemistry , Pharmacology , Flow Cytometry , Glial Fibrillary Acidic Protein , Metabolism , Hypoxia , Hypoxia-Inducible Factor 1, alpha Subunit , Metabolism , Indazoles , Pharmacology , Mesenchymal Stem Cells , Physiology , Neurogenesis , Physiology , Neuroglia , Metabolism , Physiology , Neurons , Physiology , Olfactory Mucosa , Potassium Channels , Signal Transduction , Tubulin , MetabolismABSTRACT
OBJECTIVE@#To observe the biological characteristics of the human olfactory mucosa mesenchymal stem cells (hOM-MSCs).@*METHODS@#The hOM-MSCs were isolated, cultured and identified in vitro. Scanning electron microscope and transmission electron microscope were used to observe the ultrastructure of hOMMSCs. Th e cells were induced towards adipocyte, osteocyte, neural stem cells, neural-like-cells in vitro.@*RESULTS@#The hOM-MSCs were mainly in spindle shape, arranged with radial colony. The hOMMSCs expressed CD73 and CD90 but no CD34 and CD45. Th e short and thick microvilli processes were seen at the surface of hOM-MSCs by scanning electron microscope, and 2 different cellular morphology of hOM-MSCs were seen under transmission electron microscope. Moreover, the hOMMSCs could be differentiated into adipocyte, osteocyte, neural stem cells and neural cells.@*CONCLUSION@#The hOM-MSCs possess general biological characteristics of MSCs and display multiple differentiation functions. They can be served as ideal seed cells in tissue-engineering for injury repair.