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Objective To examine the neuroanatomical substrates underlying the effects of minocycline in alleviating lipopolysaccharide (LPS)-induced neuroinflammation. Methods Forty C57BL/6 male mice were randomly and equally divided into eight groups. Over three conse-cutive days, saline was administered to four groups of mice and minocycline to the other four groups. Immediately after the administration of saline or minocycline on the third day, two groups of mice were additionally injected with saline and the other two groups were injected with LPS. Six or 24 hours after the last injection, mice were sacrificed and the brains were removed. Immunohistochemical staining across the whole brain was performed to detect microglia activation via Iba1 and neuronal activation via c-Fos. Morphology of microglia and the number of c-Fo-positive neurons were analyzed by Image-Pro Premier 3D. One-way ANOVA and Fisher's least-significant differences were employed for statistical analyses. Results Minocycline alleviated LPS-induced neuroinflammation as evidenced by reduced activation of microglia in multiple brain regions, including the shell part of the nucleus accumbens (Acbs), paraventricular nucleus (PVN) of the hypothalamus, central nucleus of the amygdala (CeA), locus coeruleus (LC), and nucleus tractus solitarius (NTS). Minocycline significantly increased the number of c-Fo-positive neurons in NTS and area postrema (AP) after LPS treatment. Furthermore, in NTS-associated brain areas, including LC, lateral parabrachial nucleus (LPB), periaqueductal gray (PAG), dorsal raphe nucleus (DR), amygdala, PVN, and bed nucleus of the stria terminali (BNST), minocycline also significantly increased the number of c-Fo-positive neurons after LPS administration. Conclusion Minocycline alleviates LPS-induced neuroinflammation in multiple brain regions, possibly due to increased activation of neurons in the NTS-associated network.
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Animals , Female , Male , Mice , Lipopolysaccharides/toxicity , Mice, Inbred C57BL , Minocycline/pharmacology , Neuroinflammatory Diseases , Solitary NucleusABSTRACT
Objective To investigate the effect of extract of Ginkgo biloba (Egb) on apoptosis of nerve cells and its mechanism after spinal cord injury (SCI) in rats. Methods Forty eight adult SD rats weighing 200-230 g were divided equally and randomly into Egb group and normal saline (NS) group. After hemisectian of spinal cord at T9 vertebrae level, rats in Egb group were lavaged with 2 ml EGB (20 mg) daily and those in NS group with 2 ml NS daily. Tissue sections were collected and stained with Nissl's staining, myelin sheath staining, and inducible nitric oxide synthase (iNOS) immunohisto-chemistry as well as terminal deoxynueleotidyl transferase-mediated dUTP nick end lebeling (TUNEL) at days 1,7, 14 and 21 respectively to evaluate the injured spinal cord tissues after six rats from each group were sacrificed Results Nissl's staining manifested less swelling of the nerve cells near the injury epi-center ( rostral and caudal ), smaller cavity and demyelinated area and higher ratio of bilateral anterior horn neurons of transection side to normal side in Egb group, compared with NS group ( P <0.05). Ap-optotie index (AI) and expression of iNOS in NS group were higher than those in Egb group ( P <0.01 or P <0. 05). Furthermore, the rate of iNOS-positive cells was positively correlated with the AI (r = 0.729, P<0.01) after SCI. Conclusion Egb can prevent nerve cells from apoptosis after SCI in rats, as may be related with inhibition of expression of iNOS.
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BACKGROUND: At present, hemopoietic stem cells have been proved to differentiate into nerves in rodents animals. As for the human, this topic is in debate.OBJECTIVE: To investigate the neural differentiation potential of human umbilical cord blood-derived AC133+ cells. DESIGN, TIME AND SETTING: Control experiments by grouping were performed in the Hematology Institute of Tianjin Hematology Hospital and Central Laboratory of Neurosurgery in Yuquan Hospital of Tsinghua University from August 2005 to December 2007.MATERIALS: Human umbilical cord blood was sampled from full-term newborn infant. Fetal brain-derived trophic support cells were harvested from aborted fetus of 22 weeks old.MAIN OUTCOME MEASURES: After the induction, human cord blood cells were collected at weeks 1, 2 and 4. RT-PCR was used to detect the expression of nestin, bone morphogenetic protein-2 and neural cell adhesion molecule. Immunocytochemistry method was applied to detect the cytotype-specific antigen. RESULTS: In the culture medium containing epidermal growth factor and basic fibroblast growth factor, human cord blood AC133+ cells could express nestin and bone morphogenetic protein-2, which were down-regulated even closed up in suboptimal condition. In the DMEM/F12 medium supplemented with epidermal growth factor, basic fibroblast growth factor and brain-derived neurotrophic factor, the gene expression of bone morphogenetic protein-2 and nestin continued in optimal condition at 2 weeks. Moreover neural cell adhesion molecule, another gene of neural cells, also expressed in this condition. AC133+ cells co-cultured with fetal brain-derived trophic support cells exhibited similar expressions. In the optimal non-cell-cell contact co-culture system, glial fibrillary acidic protein-positive cells were found by immuocytochemistry, while neuronal marker β-tubulin Ⅲwas expressed in the cell-cell direct contact system. These outcomes indicated that human cord blood isolated AC133+ cells may have an effect through gene rearrangement on inducing stem cells to express nerve cell development factors.CONCLUSION: The human umbilical cord blood-derived AC133+ cells contain some multipotential stem cells with differentiation potential, neural differentiation-related antigen when exposed to a suitable microenvironment.
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BACKGROUND:Human umbilical cord blood (CB)-derived CD133+ cells are a minority population of primitive cells with extensive proliferation and differentiation potentials,which are considered to have ability of neural differentiation.OBJECTIVE:We hypothesized a possible application of CB CD133+ cells in the cognitive and survival function of mice with dementia,the present study observed the changes of the cognitive function and survival of amyloid precursor protein(APP)transgenic mice after CB CD 133+ cells transplantation to verify the above assumption.DESIGN,TIME AND SETTING:A completely randomized block design of animal experiments was performed in the Hematology Institute of Tianjin Hematology Hospital from September 2005 to December 2007.MATERIALS:Forty-eight eight-month-old male APP 695 transgenic C57BL/6 (BDF1/KM) mice were selected in this experiments All mice were divided randomly into three groups:control group (n=8),CD133+ transplantation group (n=20) and CD133 transplantation group (n=20).METHODS:Mice in control groups received an intraventricular injection of 10 μL phosphate buffered saline (PBS).The transgenic mice that received an intraventricular injection of 10 μL CD133+ (5×104/μL) and CD133 CB cells (5×104/μL) respectively.MAIN OUTCOME MEASURES:Radial ann water maze (RAWM) was used to evaluate cognitive function of the mice and the survival days of mice in different groups were recorded,lmmunohistochemical assessments and Dil Fluorescence labeled way was used to detect the differentiation phenotype of transplanted cells.RESULTS:The cognitive function of the mice in CD133+ transplantation group was significantly improved compared with the mice in CD 133- transplantation and control groups both 30 and 180 days after transplantation (P＜0.05).The mean survival time of the mice in CD133+ transplantation group was significantly increased compared with CD133 transplantin group and control group (P＜0.05).It was observed that the transplantation CB CD133+ cells labeled with Dil migrated into several brain regions at day 30 post-transplantation.These cells were stained for human βⅢ-tubulin,neuralfilement(NF),neuron specific enolase (NSE),and glial fibriliary acidic protein(GFAP).However,in the brain of mice that received CD133 cells transplantation,CB cells were distributed mainly in and around the lateral ventricle at day 30 and 180 post-transplantation and GFAP-,βⅢ-tubulin- and NSE-positive cells were rarely detected.After intraventricular transplantation of CB CD133+ cells,the percentage of transplanted Dil-labeled CB cells expressing βⅢ-tubulin was significant higher at day 30 than at day 180,and the percentage of CB cells expressing NSE was significant lower at day 30 than that at day 180 (both P＜0.01).The percentage of CB cells expressing GFAP was relatively constant between the days 30 and 180 after transplantation (P＞0.05).CONCLUSION:The result of this experiment suggested that the cognitive and survival function improvement achieved by transplantation of CB CD133+ cells is mainly due to a replacement of dysfunctional cells or augmentation of neural circuit by CB CD133+ cells transplantation.
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The candidate donor cells for repairing the central nervous system included olfactory ensheathing cells,oligodendrocyte progenitor cells and Schwann cells. Among them,oligodendrocyte progenitor cells are difficult to collect in a large amount; Schwann cells are difficult to traverse glial scar,so olfactory ensheathing cells were the most appropriate groups. Olfactory ensheathing cells in vitro were flexible and of plasticity,thus were capable of adapting to the transplantation microenviroment and benefit for the neural regeneration. Olfactory ensheathing cells could improve the function after injury of spinal dorsal roots,which were probably related to the component of grafts. The proper preparation and mixed olfactory ensheathing cells could contribute to recovery of function. Although the low immunogen of fetal brain,the administration of immunosuppressant would be necessary. In spite of reconstruction of damaged pathway of nervous system,olfactory ensheathing cells were able to promoting sprout of fibers,release neurotransmitters at the non-synaptic sites and improve microenvironment of damaged sites as well,which compensated for the dysfunction in central nervous system injury. Insight into cell biological property and behavior after transplantation would help understand and exert theoretical influence on the repair of spinal cord injury.
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OBJECTIVE:In recent years, chitosan has been widely used as tissue engineering scaffolds. In this paper we reviewed the research progress in chitosan biocompatibility and gave a hypothesison possible mechanism of interactions between cells and chitosan. A model system to test this hypothesis was also discussed. DATA SOURCES: Literatures about chitosan biocompatibility were retrieved with computer in Medline, Pubmed and Elsevier from January 1998 to December 2006 with the key words of."chitosan, biocompatibility, surface charge, cell adhesion" in English.STUDY SELECTION: Literatures about chitosan biocompatibility and interactions between chitosan and cells, especially the influence of chitosan charges on cell attachment, were included, whereas repeated experiments were excluded.DATA EXTRACTION: Totally 374 literatures were collected. Among which, 30 were admitted and reviewed.DATA SYNTHESIS: Many mammalian cells can adhere, spread and proliferate on chitosan materials. It is widely accepted that the biocompatibility of chitosan is due to the electrostatic attractive force between positively charged amino groups on chitosan chains and negatively charged cell membranes. However, the pKa value of chitosan amino groups is 6.2-6.8 and the positive charge of chitosan chains is largely decreased under physiological condition as a result of amino groups unprotonation. Thus whether the chitosan's biocompatibility is due to its positive charge remains doubtful and needs further study.CONCLUSION: Based on prior studies, we hypothesize that the positive charge of amino groups on chitosan chains might not be the major factor in biocompatibility of chitosan material. Agarose/chitosan blending hydrogels is supposed to be an appropriate model system to test this hypothesis.
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BACKGROUND: It was thought that there was no regeneration capacityin central nerves. Recent research shows that regeneration capacity of injured neural axons and recovery of some neurological functions can be achieved by changing local surroundings after spinal cord injury (SCI).OBJECTIVE: To probe into whether the transplantation of fetal olfactory ensheathing cells (OECs) in recovering the neurological functions of patients with chronic SCI is safe, feasible, and effective.DESIGN: Auto-control observation before and after surgery.SETTING: Neurological Research and Treatment Center of Beijing Xishan Hospital; Second Department of Neurosurgery in Beijing Chaoyang Hospital Affiliated to Capital University of Medical Sciences; Second Department of Neurosurgery in Naval General Hospital.PARTICIPANTS: A total of 171 patients with chronic spinal cord injury were selected from the Second Department of Neurosurgery in Beijing Chaoyang Hospital Affiliated to Capital University of Medical Sciences and the Second Department of Neurosurgery in Naval General Hospital betweenNovember 2001 and February 2003, of which there are 147 patients with complete injury and 24 ones with incomplete injury. Post-injury period ranged from 0.5 to 18 years. Process of treatment is discussed and permitted by relevant Medical Ethics Committees. Cells were obtained from voluntary donors and patients agreed to receive the treatment.METHODS: ① Fetal olfactory bulbs were cultured for 12-17 days after being digested into single cells. ② Fetal OECs were transplanted into sites rostral and caudal to the epienter. ③ Neurological functions of all patients 2-8 weeks before and after operation were evaluated according to the scoring standard of ASIA.MAIN OUTCOME MEASURES: ① Status of functional recovery in spinal cord of patients after transplantation of OECs. ② Harmful events and side effects.RESULTS: A total of 171 patients were involved in the analysis of results.①Status of functional recovery in spinal cord of patients with OECs transplantation: Partial neurological functions of 171 patients rapidly recovered,whose motor function score increased from (34.5±20.3) points before operation to (42.0±20.0) points (P ＜ 0.001) after operation, score of light touch increased from (47.2±24.0) points to (61.8±23.0) points (P ＜ 0.001) after operation,score of pain sense increased from (48.6±23.5) points to (64.0±22.8) points (P ＜ 0.001). ②Harmful events and side-effects: Early manifestations of spinal cord injury induced by infection in surgical area of one patient aggravated; two patients suffered from serious pulmonary infection,one patient from thalamic hemorrhage. Three patients mentioned above died of serious respiration and circulatory failures.CONCLUSION: OEC transplantation can rapidly promote partial neurological function of patients with chronic SCI, while the mechanism needs further observing.
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<p><b>OBJECTIVE</b>To explore indication and approaches of neurotomy of tibial nerve for the treatment of the talipes equinovarus and spastic paralysis.</p><p><b>METHOD</b>A total of 25 patients including 15 patients with cerebral paralysis and other 10 patients were diagnosed with clear etiology, spastic muscles with supplied nerves were analyzed in detail, neurotomy of the tibial nerve was performed under microscope, during operation, motor nerve was lovated with electronic stimuli and monitored with induced electromyography. The surgical results were analyzed.</p><p><b>RESULTS</b>A total of 36 of 37 (97%) neurotomy of the tibial nerve were improved with dorsum flex of ankle at 10 - 45 degree, and 22 of 24 (85%) talipes equinovarus improved clinically. Of 37 feet with surgery, 24 feet (65%) were in normal position and could touch ground completely, 9 feet (24%) had 10 degree with ground or could contact ground with external one third of the feet, 4 feet (11%) were abnormal. Of 25 patents, 21 (84%) had improvement of motor activity at discretion, 5 patients (20%) improved dramatically. All the 4 patients failed after the operation were cerebral paralysis, and were presumably related to disorders of spinal function, abnormal reflex and the disappearance of inhibitory reflex.</p><p><b>CONCLUSION</b>Neurotomy is an effective method to treat talipes equinovarus, and can improve the motor activity of low extremity.</p>
Subject(s)
Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Clubfoot , General Surgery , Equinus Deformity , General Surgery , Microsurgery , Neurosurgical Procedures , Methods , Tibial Nerve , General Surgery , Treatment OutcomeABSTRACT
<p><b>OBJECTIVE</b>To evaluate the restoration of function after spinal cord injury (SCI) in patients of different ages who have underwent intraspinal transplantation of olfactory ensheathing cells (OECs).</p><p><b>METHODS</b>One hundred and seventy-one SCI patients were included in this study. Of them, 139 were male and 32 were female, with age ranging from 2 to 64 years (mean, 34.9 years). In all SCI patients the lesions were injected at the time of operation with OECs. According to their ages, the patients were divided into 5 groups: </= 20 years group (n = 9), 21 - 30 years group (n = 54), 31 - 40 years group (n = 60), 41 - 50 years group (n = 34) and > 51 years group (n = 14). The spinal cord function was assessed based on the American Spinal Injury Association (ASIA) Classification System before and 2 - 8 weeks after OECs transplantation. One-way ANOVA and q test were used for statistical analysis, and the data were expressed as mean +/- SD.</p><p><b>RESULTS</b>After surgery, the motor scores increased by 5.2 +/- 4.8, 8.6 +/- 8.0, 8.3 +/- 8.8, 5.7 +/- 7.3 and 8.2 +/- 7.6 in 5 age groups respectively (F = 1.009, P = 0.404); light touch scores increased by 13.9 +/- 8.1, 15.5 +/- 14.3, 12.0 +/- 14.4, 14.1 +/- 18.5 and 24.8 +/- 25.3 respectively (F = 1.837, P = 0.124); and pin prick scores increased by 11.1 +/- 7.9, 17.2 +/- 14.3, 13.2 +/- 11.8, 13.6 +/- 13.9 and 25.4 +/- 24.3 respectively (F = 2.651, P = 0.035). Restoration of pin prick in > 51 years group was better than other age groups except 21 - 30 years group.</p><p><b>CONCLUSION</b>OECs transplantation can improve the neurological function of spinal cord of SCI patients regardless of their ages. Further research into the long-term outcomes of the treatment will be required.</p>