Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic ker...Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic keratopathy are limited.In this study,an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor(CTH-mNGF).Its effectiveness was evaluated in corneal denervation(CD)mice and patients with neurotrophic keratopathy.In the preclinical setting,CTH-mNGF was assessed in a murine corneal denervation model.CTH-mNGF was transparent,thermosensitive,and ensured sustained release of mNGF for over 20 hours on the ocular surface,maintaining the local mNGF concentration around 1300 pg/mL in vivo.Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice.A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy.Patients received topical CTH-mNGF twice daily for 8 weeks.Fluorescein sodium images,Schirmer’s test,intraocular pressure,Cochet-Bonnet corneal perception test,and best corrected visual acuity were evaluated.In total,six patients(total of seven eyes)diagnosed with neurotrophic keratopathy were enrolled.After 8 weeks of CTH-mNGF treatment,all participants showed a decreased area of corneal epithelial defect,as stained by fluorescence.Overall,six out of seven eyes had fluorescence staining scores<5.Moreover,best corrected visual acuity,intraocular pressure,Schirmer’s test and Cochet-Bonnet corneal perception test results showed no significant improvement.An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes.This study demonstrates that CTH-mNGF is transparent,thermosensitive,and has sustained-release properties.Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy,being convenient and cost effective.展开更多
Retroperitoneal operations, such as radical prostatectomy, often damage the cavernous nerve, resulting in a high incidence of erectile dysfunction. Although improved nerve-sparing techniques have reduced the incidence...Retroperitoneal operations, such as radical prostatectomy, often damage the cavernous nerve, resulting in a high incidence of erectile dysfunction. Although improved nerve-sparing techniques have reduced the incidence of nerve injury, and the administration of phosphodiesterase type 5 inhibitors has revolutionized the treatment of erectile dysfunction, this problem remains a considerable challenge. In recent years, scientists have focused on brain-derived neurotrophic factor and vascular endothelial growth factor in the treatment of cavernous nerve injury in rat models. Results showed that both compounds were capable of enhancing the regeneration of the cavernous nerve and that activation of the Janus kinase （JAK）/signal transducer and activator of transcription （STAT） pathway played a major role in the process.展开更多
The present study co-cultured human embryonic olfactory ensheathJng cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal...The present study co-cultured human embryonic olfactory ensheathJng cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal fluid. Enzyme linked immunosorbent assay was used to detect nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor secretion in the supernatant of co-cultured cells. Results showed that the number of all cell types reached a peak at 7-10 days, and the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor peaked at 9 days. Levels of secreted nerve growth factor were four-fold higher than brain-derived neurotrophic factor, which was three-fold higher than glial cell line-derived neurotrophic factor. Increasing concentrations of cerebrospinal fluid （10%, 20% and 30%） in the growth medium caused a decrease of neurotrophic factor secretion Results indicated co-culture of human embryonic olfactory ensheathing cells, human Schwann cells human amniotic epithelial cells and human vascular endothelial cells improved the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor. The reduction of cerebrospinal fluid extravasation at the transplant site after spinal cord injury is beneficial for the survival and secretion of neurotrophic factors from transplanted cells.展开更多
Objective： To detect the expressions of brain-derived neurotrophic factor （BDNF） and nerve growth factor （NGF） in purified rat choroid plexus epithelial cells in vitro. Methods： Primary and passage choroid plexu...Objective： To detect the expressions of brain-derived neurotrophic factor （BDNF） and nerve growth factor （NGF） in purified rat choroid plexus epithelial cells in vitro. Methods： Primary and passage choroid plexus epithelial cells were obtained from newborn, one-day Spragne-Dawley rats. The expressions of BDNF and NGF were measured by qRT-PCR and Western blottingting. The secretions of BDNF and NGF were detected by ELISA. Cell supematants of primary cells, purified cells and passage 1 cells were harvested. Results： The expression of BDNF in the purified cells was significantly lower than that in the primary cells （P〈0.05）, and it in the primary cells and the purified cells was significantly higher than that in the passage 1 cells （P〈0.05）. The expression of NGF was significantly higher in the purified cells than in the primary cells and the passage 1 cells （P〈0.05）. It in the passage 1 cells was significantly higher than that in the primary cells （P〈0.05）. Conclusion： The time of CPECs transplantation for central nervous system diseases should be selected based on their secretory function and features,which could lead to better and more effective treatment.展开更多
We previously prepared nerve growth factor poly-lactide co-glycolid sustained-release microspheres to treat rat sciatic nerve injury using the small gap sleeve technique.Multiple growth factors play a synergistic role...We previously prepared nerve growth factor poly-lactide co-glycolid sustained-release microspheres to treat rat sciatic nerve injury using the small gap sleeve technique.Multiple growth factors play a synergistic role in promoting the repair of peripheral nerve injury;as a result,in this study,we added basic fibroblast growth factors to the microspheres to further promote nerve regeneration.First,in an in vitro biomimetic microenvironment,we developed and used a drug screening biomimetic microfluidic chip to screen the optimal combination of nerve growth factor/basic fibroblast growth factor to promote the regeneration of Schwann cells.We found that 22.56 ng/mL nerve growth factor combined with 4.29 ng/mL basic fibroblast growth factor exhibited optimal effects on the proliferation of primary rat Schwann cells.The successfully prepared nerve growth factor-basic fibroblast growth factor-poly-lactide-co-glycolid sustained-release microspheres were used to treat rat sciatic nerve transection injury using the small gap sleeve bridge technique.Compared with epithelium sutures and small gap sleeve bridging alone,the small gap sleeve bridging technique combined with drug-free sustained-release microspheres has a stronger effect on rat sciatic nerve transfection injury repair at the structural and functional level.展开更多
AIM:To characterize changes of corneal nerve morphology and tear indices in patients with neurotrophic keratitis(NK)treated with recombinant human nerve growth factor(rhNGF).METHODS:In a prospective observational stud...AIM:To characterize changes of corneal nerve morphology and tear indices in patients with neurotrophic keratitis(NK)treated with recombinant human nerve growth factor(rhNGF).METHODS:In a prospective observational study,six patients(nine eyes)were locally treated with rhNGF.Visual acuity,corneal fluorescein staining score,the heights of the tear river,lipid layer thickness(LLT),tear ferning(TF)test,conjunctival impression cytology(CIC)examination,the densities of cornea subbasal nerve fibers were determined before and after treatment.RESULTS:Compared with baseline,there was a significant difference in corneal fluorescence staining scores(P<0.01);all patient corneal epithelial defects recovered completely within 8wk,but there was no significant improvement in the height of the tear river(P=0.202).LLT was significantly increased when compared with baseline(P=0.042);however,the function of conjunctival goblet cells and mucin content did not significantly improve using the TF test and CIC examination(P=0.557,P=0.539).After 8wk of treatment,the average corneal subbasal nerve fiber density increased significantly(P<0.01),as did the number of corneal nerve fiber branches(P=0.001).CONCLUSION:RhNGF can increase the density of corneal subbasal nerve fibers,promote the healing of persistent corneal epithelial defects and corneal ulcers in patients with NK,also improving tear function partially.展开更多
Traumatic brain injury is one of the main causes of mortality and disability worldwide.Traumatic brain injury is characterized by a primary injury directly induced by the impact,which progresses into a secondary injur...Traumatic brain injury is one of the main causes of mortality and disability worldwide.Traumatic brain injury is characterized by a primary injury directly induced by the impact,which progresses into a secondary injury that leads to cellular and metabolic damages,starting in the first few hours and days after primary mechanical injury.To date,traumatic brain injury is not targetable by therapies aimed at preventing and/or limiting the outcomes of secondary damage but only by palliative therapies.Nerve growth factor is a neurotrophin targeting neuronal and non-neuronal cells,potentially useful in preventing/limiting the outcomes of secondary damage in traumatic brain injury.This potential has further increased in the last two decades since the possibility of reaching neurotrophin targets in the brain through its intranasal delivery has been exploited.Indeed,molecules intranasally delivered to the brain parenchyma may easily bypass the blood-brain barrier and reach their therapeutic targets in the brain,with favorable kinetics,dynamics,and safety profile.In the first part of this review,we aimed to report the traumatic brain injury-induced dysfunctional mechanisms that may benefit from nerve growth factor treatment.In the second part,we then exposed the experimental evidence relating to the action of nerve growth factor(both in vitro and in vivo,after administration routes other than intranasal)on some of these mechanisms.In the last part of the work,we,therefore,discussed the few manuscripts that analyze the effects of treatment with nerve growth factor,intranasally delivered to the brain parenchyma,on the outcomes of traumatic brain injury.展开更多
Studies have shown that retreatment of the distal stoma after nerve grafting can stimulate nerve regeneration. The present study attempted to verify the effects of reanastomosis of the distal stoma, after nerve grafti...Studies have shown that retreatment of the distal stoma after nerve grafting can stimulate nerve regeneration. The present study attempted to verify the effects of reanastomosis of the distal stoma, after nerve grafting, on nerve regeneration by assessing brain-derived neurotrophic factor expression in 2-month-old rats. Results showed that brain-derived neurotrophic factor expression in L2-4 dorsal root ganglia began to increase 3 days after autologous nerve grafting post sciatic nerve injury, peaked at 14 days, decreased at 28 days, and reached similar levels to the sham-surgery group at 56 days. Brain-derived neurotrophic factor expression in L2-4 dorsal root ganglia began to increase 3 days after reanastomosis of the distal stoma, 59 days after autologous nerve grafting post sciatic nerve injury, significantly increased at 63 days, peaked at 70 days, and gradually decreased thereafter, but remained higher compared with the sham-surgery group up to 112 days. The results of this study indicate that reanastomosis of the distal stoma after orthotopic nerve grafting stimulated brain-derived neurotrophic factor expression in L2.4 dorsal root ganglia.展开更多
BACKGROUND： Previous studies have shown that nerve regeneration factor （NRF） provides neuroprotective effects. However, the neuroprotective effects on retinal ganglion cells in an animal model of glaucoma remain un...BACKGROUND： Previous studies have shown that nerve regeneration factor （NRF） provides neuroprotective effects. However, the neuroprotective effects on retinal ganglion cells in an animal model of glaucoma remain uncertain. OBJECTIVE： To determine the neuroprotective effects of NRF on retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure and to compare the effects on brain-derived neurotrophic factor （BDNF）. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at Jiangsu Provincial Key Laboratory of Neural Regeneration from September 2006 to August 2007. MATERIALS： Sterone, a major component of NRF, was provided by the Key Laboratory of Neural Regeneration, Nantong University in China; BDNF was provided by BioDesign Inc., USA. METHODS： A total of 24 healthy rabbits were randomly assigned to NRF, BDNF, and phosphate buffered saline groups, with 8 rabbits per group. The left eyes were considered normal controls, and acute hyper-intraocular pressure was induced in the right eyes via anterior chamber perfusion. The right camera vitrea bulbi was injected with 4.5 μg NRF, 3.75 μg BDNF, or 5 μL 0.1 mol/L phosphate buffered saline, respectively. MAIN OUTCOME MEASURES： Retinal ganglion cells were reverse-labeled using horseradish peroxidase to quantify cell density at 2, 4, and 6 mm from the optic disc edge. RESULTS： NRF increased the number of surviving retinal ganglion cells at the optic disc edge （P 〈 0.01 or P 〈 0.05）. The density of surviving retinal ganglion cells decreased with increasing distance from the optic disc. The number of retinal ganglion cells in the BDNF group was similar to the NRF group （P 〉 0.05）. At 2, 4, and 6 mm away from the optic disc edge, there was no significant difference in retinal ganglion cell density between NRF and BDNF groups （P〉 0.05）. CONCLUSION： NRF provided protection to retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure, Le., NRF enhanced the survival rate of retinal ganglion cells. The neuroprotective effect was similar to BDNF.展开更多
The optic nerve is a viscoelastic solid-like biomaterial.Its normal stress relaxation and creep properties enable the nerve to resist constant strain and protect it from injury.We hypothesized that stress relaxation a...The optic nerve is a viscoelastic solid-like biomaterial.Its normal stress relaxation and creep properties enable the nerve to resist constant strain and protect it from injury.We hypothesized that stress relaxation and creep properties of the optic nerve change after injury.Moreover,human brain-derived neurotrophic factor or umbilical cord blood-derived stem cells may restore these changes to normal.To validate this hypothesis,a rabbit model of optic nerve injury was established using a clamp approach.At 7 days after injury,the vitreous body received a one-time injection of 50 μg human brain-derived neurotrophic factor or 1 × 106 human umbilical cord blood-derived stem cells.At 30 days after injury,stress relaxation and creep properties of the optic nerve that received treatment had recovered greatly,with pathological changes in the injured optic nerve also noticeably improved.These results suggest that human brain-derived neurotrophic factor or umbilical cord blood-derived stem cell intervention promotes viscoelasticity recovery of injured optic nerves,and thereby contributes to nerve recovery.展开更多
BACKGROUND： Studies have shown that agmatine can reduce inhibition of neuronal regeneration by increasing cyclic adenosine monophosphate and brain-derived neurotrophic factor （BDNF） in the hippocampus of morphine-d...BACKGROUND： Studies have shown that agmatine can reduce inhibition of neuronal regeneration by increasing cyclic adenosine monophosphate and brain-derived neurotrophic factor （BDNF） in the hippocampus of morphine-dependent rats. The hypothesis that agmatine exerts similar effects on facial nerve injury deserves further analysis. OBJECTIVE： To study the effects of peritoneal agmatine injection on BDNF levels in the rat brainstem after facial nerve injury. DESIGN, TIME AND SETTING： A controlled animal experiment was performed at the Department of Otolaryngology-Head and Neck Surgery at the Second Affiliated Hospital, Chongqing University of Medical Sciences （Chongqing, China）, between October and December in 2007. MATERIALS： Twenty-four male Sprague-Dawley rats were randomly divided into a control, a lesion, and an agmatine treatment group, with eight rats in each group. Bilateral facial nerve anastomosis was induced in the lesion and agmatine treatment groups, while the control group remained untreated. A rat BDNF Enzyme-linked immunosorbent assay kit was used to measure BDNF levels in the brainstem facial nucleus. METHODS： Starting on the day of lesion, the agmatine group received a peritoneal injection of 100 mg/kg agmatine, once per day, for a week, whereas rats in the lesion group received saline injections. MAIN OUTCOME MEASURES： BDNF levels in the brainstem containing facial nucleus were measured by ELISA. RESULTS： Twenty-four rats were included in the final analysis without any loss. Two weeks after lesion, BDNF levels were significantly higher in the lesion group than in the control group （P 〈 0.01）. A significant increase was noted in the agmatine group compared to the lesion group （P 〈 0.01）. CONCLUSION： Agmatine can substantially increase BDNF levels in the rat brainstem after facial nerve injury.展开更多
Changes of brain-derived neurotrophic factor （BDNF） expression reflect function of nerve cells; meanwhile, they play a significant role in researching interventions on plerosis of nerve injury. OBJECTIVE： To observ...Changes of brain-derived neurotrophic factor （BDNF） expression reflect function of nerve cells; meanwhile, they play a significant role in researching interventions on plerosis of nerve injury. OBJECTIVE： To observe and compare the effects on changes of BDNF expression in rats with spinal cord injury between microencapsulated sciatic nerve cells of rabbits and only transplanting sciatic nerve cells of rabbits. DESIGN： Randomized controlled animal study. SETTING： Medical School of Jiujiang College. MATERIALS： The experiment was carried out in the Medical Science Researching Center, Jiujiang College from May 2004 to May 2006. A total of 90 healthy adult SD rats, weighing 250 - 300 g, of either gender; and 10 rabbits, weighing 2.0 - 2.5 kg, of either gender, were provided by Jiangxi Experimental Animal Center. METHODS： Sciatic nerve tissue of rabbits was separated to make cell suspension, After centrifugation, suspension was mixed with 15 g/L alginate saline solution and ejaculated to 20 mmol/L barium chloride saline solution by double-cavity ejaculator. The obtained cell microcapsules were suspended in saline. Rats were randomly divided into microencapsulated group, only suspension group, and only injured group with 30 animals in each group. After anesthesia, T10 spinous process and vertebra lamina of rats in the former two groups were exposed. Spinal cord tissue in 2-mm length was removed from rats by spinal cord right hemi-section. The gelatin sponges with the size of 2 mm × 2 mm × 2 mm were grafted as filing cage, and absorbed 10 μL microencapsulated sciatic nerve cells of rabbit in the microencapsulated group and 10 μL sciatic nerve cells of rabbits in the only suspension group; respectively. No graft was placed in the only injured group. MAIN OUTCOME MEASURES： On the 1^st, 3^rd, 7^th, 14^th and 28^th days after operation, immunohistochemistry （SABC technique） was used to detect distribution and amount of positive-reactive neurons in BDNF of spinal cord samples which were selected as 2 cm away from the injured surface. RESULTS： All the 90 rats were involved in the final analysis. Masses of brown-yellow particles were found in the microencapsulated group, and most of them were distributed in the spinal cord anterior horn neurons and glial cells. The positive-reactive neuron particles were also found in the white matter and gray matter. On the 3^rd, 7^th, 14^th and 28^th days after operation, amount of positive-reactive neurons in BDNF in the microencapsulated group was higher than that in the only injured group （P 〈 0.01） and only suspension group （P 〈 0.05）. CONCLUSION： After transplanting microencapsulated nerve cell suspension into injured spinal cord of rats, distribution and amount of positive-reactive neurons in BDNF of local samples at injured surface are increased remarkably as compared with those by using tissue cell transplantation.展开更多
Parkinson＇s disease is a progressive neurological disease characterized by the degeneration of dopaminergic neurons in the substantia nigra.A highly similar pattern of neurodegeneration can be induced by 1-methyl-4-p...Parkinson＇s disease is a progressive neurological disease characterized by the degeneration of dopaminergic neurons in the substantia nigra.A highly similar pattern of neurodegeneration can be induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine（MPTP） or 1-methyl-4-phenylpyridinium ion（MPP＋）,which cause the death of dopaminergic neurons.Administration of MPTP or MPP＋ results in Parkinson＇s disease-like symptoms in rodents.However,it remains unclear whether intracerebroventricular MPP＋ administration affects neurogenesis in the substantia nigra and subgranular zone or whether brain-derived neurotrophic factor alters the effects of MPP＋.In this study,MPP＋（100 nmol） was intracerebroventricularly injected into mice to model Parkinson＇s disease.At 7 days after administration,the number of bromodeoxyuridine（Brd U）-positive cells in the subgranular zone of the hippocampal dentate gyrus increased,indicating enhanced neurogenesis.In contrast,a reduction in Brd U-positive cells was detected in the substantia nigra.Administration of brain-derived neurotrophic factor（100 ng） 1 day after MPP＋ administration attenuated the effect of MPP＋ in the subgranular zone and the substantia nigra.These findings reveal the complex interaction between neurotrophic factors and neurotoxins in the Parkinsonian model that result in distinct effects on the catecholaminergic system and on neurogenesis in different brain regions.展开更多
Objective:To explore the protective mechanisms of nerve growth factor (NGF) on spinal cord injury (SCI) and provide theoretical basis for its clinical application. Methods: The SCI of Wistar rats was done by Allens w...Objective:To explore the protective mechanisms of nerve growth factor (NGF) on spinal cord injury (SCI) and provide theoretical basis for its clinical application. Methods: The SCI of Wistar rats was done by Allens weight dropping way by a 10 g×2.5 cm impact on the posterior of spinal cord T 8. NGF (3 g/L, 20 μl) or normal saline was injected through catheter into subarachnoid space 2, 4, 8, 12 and 24 h after SCI. The expression of N-methyl-D-asparate receptor 1 (NMDAR 1) and neuronal constitutive nitric oxide synthase (ncNOS) mRNA in rat spinal cord was detected by in situ hybridization. Results: Abnormal expression of NMDAR 1 and ncNOS mRNA appeared in spinal ventral horn motorneuron in injured rats, as compared with that in control group. The expression of NMDAR 1 and ncNOS mRNA in NGF group was significantly lower than that in saline group (P<0.01). Conclusion: NGF can protect spinal cord against injury in vivo. One of the mechanisms is that NGF can prohibit NMDAR 1 and nitric oxide (NO) production after spinal cord injury.展开更多
Objective To investigate the regulatory effects of nerve growth factor （NGF） on basal and capsaicin-induced release of neuropeptide substance P （SP） in primary cultured embryonic rat dorsal root ganglion （DRG） n...Objective To investigate the regulatory effects of nerve growth factor （NGF） on basal and capsaicin-induced release of neuropeptide substance P （SP） in primary cultured embryonic rat dorsal root ganglion （DRG） neurons. Methods DRGs were dissected from 15-day-old embryonic Wistar rats. DRG neurons were dissociated and cultured, and then exposed to different concentrations of NGF （10 ng/mL, 30 ng/mL, or 100 ng/mL） for 72 h. The neurons cultured in media without NGF served as control. RT-PCR were used for detecting the mRNAs of SP and vanilloid receptor 1 （VR1） in the DRG neurons. The SP basal and capsaicin （100 nmol/L）-induced release in the culture were measured by radioimmunoassay （RIA）. Results SP mRNA and VR1 mRNA expression increased in primary cultured DRG neurons in a dose-dependent manner of NGF. Both basal release and capsaicin-evoked release of SP increased in NGF-treated DRG neurons compared with in control group. The capsaicin-evoked release of SP also increased in a dose-dependent manner of NGF. Conclusion NGF may promote both basal release and capsaicin-evoked release of SP. NGF might increase the sensitivity of nociceptors by increasing the SP mRNA or VR1 mRNA.展开更多
Objective To investigate the expression of nerve growth factor （NGF） and glial cell line-derived neurotrophic factor （GDNF） in monkeys of resuscitation after selective cerebral ultraprofound hypothermia and blood ...Objective To investigate the expression of nerve growth factor （NGF） and glial cell line-derived neurotrophic factor （GDNF） in monkeys of resuscitation after selective cerebral ultraprofound hypothermia and blood flow occlusion. Methods The monkeys were immediately removed brain after death in operation of group A （identical temperature perfusion group） and group B （ultraprofound hypothermia perfusion group）. Immunohistochemical technique was used to determine frontal cellular expression of NGF and GDNF. Statistics were analyzed by ANOVA analyses with significance level at P 〈 0.05. Results The expressions of NGF and GDNF in the group B were significantly higher than those in the group A （P 〈 0.05）. Conclusion NGF and GDNF increased significantly in the monkeys of resuscitation after selective cerebral ultraprofound hypothermia and blood flow occlusion. It may be a protective mechanism for neuron survival and neural function recovery.展开更多
Objective: to obtain the high purified and active nerve growth factor (NGF) from mouse submaxillary glands. Methods: NGF was prepared from mouse submaxillary glands by the way of elution with CM 52 column. The molecul...Objective: to obtain the high purified and active nerve growth factor (NGF) from mouse submaxillary glands. Methods: NGF was prepared from mouse submaxillary glands by the way of elution with CM 52 column. The molecular weight and purification of NGF were detected by SDS-PAGE polyacrylamide gel electrophoresis. The biological activity of NGF was verified thorough culturing DRG. Results: About 14 kDa stained band was observed on SDS-PAGE and it promoted proliferation of dorsal root gang lia (DRG). Conclusion: Good quality of NGF could be obtained with these methods.展开更多
The integrity of retinal ganglion cells is tightly associated with diabetic macular degeneration that leads to damage and death of retinal ganglion cells,affecting vision.The major clinical treatments for diabetic mac...The integrity of retinal ganglion cells is tightly associated with diabetic macular degeneration that leads to damage and death of retinal ganglion cells,affecting vision.The major clinical treatments for diabetic macular edema are anti-vascular endothelial growth factor drugs and laser photocoagulation.However,although the macular thickness can be normalized with each of these two therapies used alone,the vision does not improve in many patients.This might result from the incomplete recovery of retinal ganglion cell injury.Therefore,a prospective,non-randomized,controlled clinical trial was designed to investigate the effect of anti-vascular endothelial growth factor drugs combined with laser photocoagulation on the integrity of retinal ganglion cells in patients with diabetic macular edema and its relationship with vision recovery.In this trial,150 patients with diabetic macular edema will be equally divided into three groups according to therapeutic methods,followed by treatment with anti-vascular endothelial growth factor drugs,laser photocoagulation therapy,and their combination.All patients will be followed up for 12 months.The primary outcome measure is retinal ganglion cell-inner plexiform layer thickness at 12 months after treatment.The secondary outcome measures include retinal ganglion cell-inner plexiform layer thickness before and 1,3,6,and 9 months after treatment,retinal nerve fiber layer thickness,best-corrected visual acuity,macular area thickness,and choroidal thickness before and 1,3,6,9,and 12 months after treatment.Safety measure is the incidence of adverse events at 1,3,6,9,and 12 months after treatment.The study protocol hopes to validate the better efficacy and safety of the combined treatment in patients with diabetic macula compared with the other two monotherapies alone during the 12-month follow-up period.The trial is designed to focus on clarifying the time-effect relationship between imaging measures related to the integrity of retinal ganglion cells and best-corrected visual acuity.The trial protocol was approved by the Medical Ethics Committee of the Affiliated Hospital of Beihua University with approval No.(2023)(26)on April 25,2023,and was registered with the Chinese Clinical Trial Registry(registration number:ChiCTR2300072478,June 14,2023,protocol version:2.0).展开更多
The trigeminal root entry zone is the zone at which the myelination switches from peripheral Schwann cells to central oligodendrocytes.Its special anatomical and physiological structure renders it susceptible to nerve...The trigeminal root entry zone is the zone at which the myelination switches from peripheral Schwann cells to central oligodendrocytes.Its special anatomical and physiological structure renders it susceptible to nerve injury.The etiology of most primary trigeminal neuralgia is closely related to microvascular compression of the trigeminal root entry zone.This study aimed to develop an efficient in vitro model mimicking the glial environment of trigeminal root entry zone as a tool to investigate the effects of glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor on the structural and functional integrity of trigeminal root entry zone and modulation of cellular interactions.Primary astrocytes and Schwann cells isolated from trigeminal root entry zone of postnatal rats were inoculated into a two-well silicon culture insert to mimic the trigeminal root entry zone microenvironment and treated with glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor.In monoculture,glial cell line-derived neurotrophic factor promoted the migration of Schwann cells,but it did not have effects on the migration of astrocytes.In the co-culture system,glial cell line-derived neurotrophic factor promoted the bidirectional migration of astrocytes and Schwann cells.Brain-derived neurotrophic factor markedly promoted the activation and migration of astrocytes.However,in the co-culture system,brain-derived neurotrophic factor inhibited the migration of astrocytes and Schwann cells to a certain degree.These findings suggest that glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor are involved in the regulation of the astrocyte-Schwann cell interaction in the co-culture system derived from the trigeminal root entry zone.This system can be used as a cell model to study the mechanism of glial dysregulation associated with trigeminal nerve injury and possible therapeutic interventions.展开更多
Using electroacupuncture and moxibustion to treat peripheral nerve injury is highly efficient with low side effects. However, the electroacupuncture-and moxibustion-based mechanisms underlying nerve repair are still u...Using electroacupuncture and moxibustion to treat peripheral nerve injury is highly efficient with low side effects. However, the electroacupuncture-and moxibustion-based mechanisms underlying nerve repair are still unclear. Here, in vivo and in vitro experiments uncovered one mechanism through which electroacupuncture and moxibustion affect regeneration after peripheral nerve injury. We first established rat models of sciatic nerve injury using neurotomy. Rats were treated with electroacupuncture or moxibustion at acupoints Huantiao （GB30） and Zusanli （ST36）. Each treatment lasted 15 minutes, and treatments were given six times a week for 4 consecutive weeks. Behavioral testing was used to determine the sciatic functional index. We used electrophysiological detection to measure sciatic nerve conduction velocity and performed hematoxylin-eosin staining to determine any changes in the gastrocnemius muscle. We used immunohistochemistry to observe changes in the expression of S100—a specific marker for Schwann cells—and an enzyme-linked immunosorbent assay to detect serum level of nerve growth factor. Results showed that compared with the model-only group, sciatic functional index, recovery rate of conduction velocity, diameter recovery of the gastrocnemius muscle fibers, number of S100-immunoreactive cells,and level of nerve growth factor were greater in the electroacupuncture and moxibustion groups. The efficacy did not differ between treatment groups. The serum from treated rats was collected and used to stimulate Schwann cells cultured in vitro. Results showed that the viability of Schwann cells was much higher in the treatment groups than in the model group at 3 and 5 days after treatment. These findings indicate that electroacupuncture and moxibustion promoted nerve regeneration and functional recovery; its mechanism might be associated with the enhancement of Schwann cell proliferation and upregulation of nerve growth factor.展开更多
基金supported by PLA General Hospital Program,No.LB20201A010024(to LW).
文摘Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic keratopathy are limited.In this study,an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor(CTH-mNGF).Its effectiveness was evaluated in corneal denervation(CD)mice and patients with neurotrophic keratopathy.In the preclinical setting,CTH-mNGF was assessed in a murine corneal denervation model.CTH-mNGF was transparent,thermosensitive,and ensured sustained release of mNGF for over 20 hours on the ocular surface,maintaining the local mNGF concentration around 1300 pg/mL in vivo.Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice.A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy.Patients received topical CTH-mNGF twice daily for 8 weeks.Fluorescein sodium images,Schirmer’s test,intraocular pressure,Cochet-Bonnet corneal perception test,and best corrected visual acuity were evaluated.In total,six patients(total of seven eyes)diagnosed with neurotrophic keratopathy were enrolled.After 8 weeks of CTH-mNGF treatment,all participants showed a decreased area of corneal epithelial defect,as stained by fluorescence.Overall,six out of seven eyes had fluorescence staining scores<5.Moreover,best corrected visual acuity,intraocular pressure,Schirmer’s test and Cochet-Bonnet corneal perception test results showed no significant improvement.An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes.This study demonstrates that CTH-mNGF is transparent,thermosensitive,and has sustained-release properties.Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy,being convenient and cost effective.
文摘Retroperitoneal operations, such as radical prostatectomy, often damage the cavernous nerve, resulting in a high incidence of erectile dysfunction. Although improved nerve-sparing techniques have reduced the incidence of nerve injury, and the administration of phosphodiesterase type 5 inhibitors has revolutionized the treatment of erectile dysfunction, this problem remains a considerable challenge. In recent years, scientists have focused on brain-derived neurotrophic factor and vascular endothelial growth factor in the treatment of cavernous nerve injury in rat models. Results showed that both compounds were capable of enhancing the regeneration of the cavernous nerve and that activation of the Janus kinase （JAK）/signal transducer and activator of transcription （STAT） pathway played a major role in the process.
基金supported by the Science andTechnology Development Program of Guangdong Province, No.2009b030801329
文摘The present study co-cultured human embryonic olfactory ensheathJng cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal fluid. Enzyme linked immunosorbent assay was used to detect nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor secretion in the supernatant of co-cultured cells. Results showed that the number of all cell types reached a peak at 7-10 days, and the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor peaked at 9 days. Levels of secreted nerve growth factor were four-fold higher than brain-derived neurotrophic factor, which was three-fold higher than glial cell line-derived neurotrophic factor. Increasing concentrations of cerebrospinal fluid （10%, 20% and 30%） in the growth medium caused a decrease of neurotrophic factor secretion Results indicated co-culture of human embryonic olfactory ensheathing cells, human Schwann cells human amniotic epithelial cells and human vascular endothelial cells improved the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor. The reduction of cerebrospinal fluid extravasation at the transplant site after spinal cord injury is beneficial for the survival and secretion of neurotrophic factors from transplanted cells.
基金Supported by grants from the National Natural Science Foundation of China(No.30973099 and No.81271341)
文摘Objective： To detect the expressions of brain-derived neurotrophic factor （BDNF） and nerve growth factor （NGF） in purified rat choroid plexus epithelial cells in vitro. Methods： Primary and passage choroid plexus epithelial cells were obtained from newborn, one-day Spragne-Dawley rats. The expressions of BDNF and NGF were measured by qRT-PCR and Western blottingting. The secretions of BDNF and NGF were detected by ELISA. Cell supematants of primary cells, purified cells and passage 1 cells were harvested. Results： The expression of BDNF in the purified cells was significantly lower than that in the primary cells （P〈0.05）, and it in the primary cells and the purified cells was significantly higher than that in the passage 1 cells （P〈0.05）. The expression of NGF was significantly higher in the purified cells than in the primary cells and the passage 1 cells （P〈0.05）. It in the passage 1 cells was significantly higher than that in the primary cells （P〈0.05）. Conclusion： The time of CPECs transplantation for central nervous system diseases should be selected based on their secretory function and features,which could lead to better and more effective treatment.
基金supported by the National Key Research and Development Program of China, No. 2016YFC1101603 (to DYZ)the National Natural Science Foundation of China, Nos. 31640045 (to YHW), 81901251 (to ML)the Natural Science Foundation of Beijing of China, No. 7204323 (to ML)
文摘We previously prepared nerve growth factor poly-lactide co-glycolid sustained-release microspheres to treat rat sciatic nerve injury using the small gap sleeve technique.Multiple growth factors play a synergistic role in promoting the repair of peripheral nerve injury;as a result,in this study,we added basic fibroblast growth factors to the microspheres to further promote nerve regeneration.First,in an in vitro biomimetic microenvironment,we developed and used a drug screening biomimetic microfluidic chip to screen the optimal combination of nerve growth factor/basic fibroblast growth factor to promote the regeneration of Schwann cells.We found that 22.56 ng/mL nerve growth factor combined with 4.29 ng/mL basic fibroblast growth factor exhibited optimal effects on the proliferation of primary rat Schwann cells.The successfully prepared nerve growth factor-basic fibroblast growth factor-poly-lactide-co-glycolid sustained-release microspheres were used to treat rat sciatic nerve transection injury using the small gap sleeve bridge technique.Compared with epithelium sutures and small gap sleeve bridging alone,the small gap sleeve bridging technique combined with drug-free sustained-release microspheres has a stronger effect on rat sciatic nerve transfection injury repair at the structural and functional level.
基金Supported by the Shaanxi Provincial Department of Science and Technology(No.2021SF-331)。
文摘AIM:To characterize changes of corneal nerve morphology and tear indices in patients with neurotrophic keratitis(NK)treated with recombinant human nerve growth factor(rhNGF).METHODS:In a prospective observational study,six patients(nine eyes)were locally treated with rhNGF.Visual acuity,corneal fluorescein staining score,the heights of the tear river,lipid layer thickness(LLT),tear ferning(TF)test,conjunctival impression cytology(CIC)examination,the densities of cornea subbasal nerve fibers were determined before and after treatment.RESULTS:Compared with baseline,there was a significant difference in corneal fluorescence staining scores(P<0.01);all patient corneal epithelial defects recovered completely within 8wk,but there was no significant improvement in the height of the tear river(P=0.202).LLT was significantly increased when compared with baseline(P=0.042);however,the function of conjunctival goblet cells and mucin content did not significantly improve using the TF test and CIC examination(P=0.557,P=0.539).After 8wk of treatment,the average corneal subbasal nerve fiber density increased significantly(P<0.01),as did the number of corneal nerve fiber branches(P=0.001).CONCLUSION:RhNGF can increase the density of corneal subbasal nerve fibers,promote the healing of persistent corneal epithelial defects and corneal ulcers in patients with NK,also improving tear function partially.
基金funded by the Italian Ministry of Health Grant:RF-2018-12366594“Nerve growth factor in paediatric severe traumatic brain injury:translational and clinical studies on a candidate biomarker and therapeutic drug”(to AC)。
文摘Traumatic brain injury is one of the main causes of mortality and disability worldwide.Traumatic brain injury is characterized by a primary injury directly induced by the impact,which progresses into a secondary injury that leads to cellular and metabolic damages,starting in the first few hours and days after primary mechanical injury.To date,traumatic brain injury is not targetable by therapies aimed at preventing and/or limiting the outcomes of secondary damage but only by palliative therapies.Nerve growth factor is a neurotrophin targeting neuronal and non-neuronal cells,potentially useful in preventing/limiting the outcomes of secondary damage in traumatic brain injury.This potential has further increased in the last two decades since the possibility of reaching neurotrophin targets in the brain through its intranasal delivery has been exploited.Indeed,molecules intranasally delivered to the brain parenchyma may easily bypass the blood-brain barrier and reach their therapeutic targets in the brain,with favorable kinetics,dynamics,and safety profile.In the first part of this review,we aimed to report the traumatic brain injury-induced dysfunctional mechanisms that may benefit from nerve growth factor treatment.In the second part,we then exposed the experimental evidence relating to the action of nerve growth factor(both in vitro and in vivo,after administration routes other than intranasal)on some of these mechanisms.In the last part of the work,we,therefore,discussed the few manuscripts that analyze the effects of treatment with nerve growth factor,intranasally delivered to the brain parenchyma,on the outcomes of traumatic brain injury.
基金supported by the Key Project of Clinical Subject of the Health Ministry,China (2010-2012),No.[2010]439
文摘Studies have shown that retreatment of the distal stoma after nerve grafting can stimulate nerve regeneration. The present study attempted to verify the effects of reanastomosis of the distal stoma, after nerve grafting, on nerve regeneration by assessing brain-derived neurotrophic factor expression in 2-month-old rats. Results showed that brain-derived neurotrophic factor expression in L2-4 dorsal root ganglia began to increase 3 days after autologous nerve grafting post sciatic nerve injury, peaked at 14 days, decreased at 28 days, and reached similar levels to the sham-surgery group at 56 days. Brain-derived neurotrophic factor expression in L2-4 dorsal root ganglia began to increase 3 days after reanastomosis of the distal stoma, 59 days after autologous nerve grafting post sciatic nerve injury, significantly increased at 63 days, peaked at 70 days, and gradually decreased thereafter, but remained higher compared with the sham-surgery group up to 112 days. The results of this study indicate that reanastomosis of the distal stoma after orthotopic nerve grafting stimulated brain-derived neurotrophic factor expression in L2.4 dorsal root ganglia.
文摘BACKGROUND： Previous studies have shown that nerve regeneration factor （NRF） provides neuroprotective effects. However, the neuroprotective effects on retinal ganglion cells in an animal model of glaucoma remain uncertain. OBJECTIVE： To determine the neuroprotective effects of NRF on retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure and to compare the effects on brain-derived neurotrophic factor （BDNF）. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at Jiangsu Provincial Key Laboratory of Neural Regeneration from September 2006 to August 2007. MATERIALS： Sterone, a major component of NRF, was provided by the Key Laboratory of Neural Regeneration, Nantong University in China; BDNF was provided by BioDesign Inc., USA. METHODS： A total of 24 healthy rabbits were randomly assigned to NRF, BDNF, and phosphate buffered saline groups, with 8 rabbits per group. The left eyes were considered normal controls, and acute hyper-intraocular pressure was induced in the right eyes via anterior chamber perfusion. The right camera vitrea bulbi was injected with 4.5 μg NRF, 3.75 μg BDNF, or 5 μL 0.1 mol/L phosphate buffered saline, respectively. MAIN OUTCOME MEASURES： Retinal ganglion cells were reverse-labeled using horseradish peroxidase to quantify cell density at 2, 4, and 6 mm from the optic disc edge. RESULTS： NRF increased the number of surviving retinal ganglion cells at the optic disc edge （P 〈 0.01 or P 〈 0.05）. The density of surviving retinal ganglion cells decreased with increasing distance from the optic disc. The number of retinal ganglion cells in the BDNF group was similar to the NRF group （P 〉 0.05）. At 2, 4, and 6 mm away from the optic disc edge, there was no significant difference in retinal ganglion cell density between NRF and BDNF groups （P〉 0.05）. CONCLUSION： NRF provided protection to retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure, Le., NRF enhanced the survival rate of retinal ganglion cells. The neuroprotective effect was similar to BDNF.
基金supported by a grant from High-Tech Research and Development Program of Jilin Province of China,No.20110492
文摘The optic nerve is a viscoelastic solid-like biomaterial.Its normal stress relaxation and creep properties enable the nerve to resist constant strain and protect it from injury.We hypothesized that stress relaxation and creep properties of the optic nerve change after injury.Moreover,human brain-derived neurotrophic factor or umbilical cord blood-derived stem cells may restore these changes to normal.To validate this hypothesis,a rabbit model of optic nerve injury was established using a clamp approach.At 7 days after injury,the vitreous body received a one-time injection of 50 μg human brain-derived neurotrophic factor or 1 × 106 human umbilical cord blood-derived stem cells.At 30 days after injury,stress relaxation and creep properties of the optic nerve that received treatment had recovered greatly,with pathological changes in the injured optic nerve also noticeably improved.These results suggest that human brain-derived neurotrophic factor or umbilical cord blood-derived stem cell intervention promotes viscoelasticity recovery of injured optic nerves,and thereby contributes to nerve recovery.
文摘BACKGROUND： Studies have shown that agmatine can reduce inhibition of neuronal regeneration by increasing cyclic adenosine monophosphate and brain-derived neurotrophic factor （BDNF） in the hippocampus of morphine-dependent rats. The hypothesis that agmatine exerts similar effects on facial nerve injury deserves further analysis. OBJECTIVE： To study the effects of peritoneal agmatine injection on BDNF levels in the rat brainstem after facial nerve injury. DESIGN, TIME AND SETTING： A controlled animal experiment was performed at the Department of Otolaryngology-Head and Neck Surgery at the Second Affiliated Hospital, Chongqing University of Medical Sciences （Chongqing, China）, between October and December in 2007. MATERIALS： Twenty-four male Sprague-Dawley rats were randomly divided into a control, a lesion, and an agmatine treatment group, with eight rats in each group. Bilateral facial nerve anastomosis was induced in the lesion and agmatine treatment groups, while the control group remained untreated. A rat BDNF Enzyme-linked immunosorbent assay kit was used to measure BDNF levels in the brainstem facial nucleus. METHODS： Starting on the day of lesion, the agmatine group received a peritoneal injection of 100 mg/kg agmatine, once per day, for a week, whereas rats in the lesion group received saline injections. MAIN OUTCOME MEASURES： BDNF levels in the brainstem containing facial nucleus were measured by ELISA. RESULTS： Twenty-four rats were included in the final analysis without any loss. Two weeks after lesion, BDNF levels were significantly higher in the lesion group than in the control group （P 〈 0.01）. A significant increase was noted in the agmatine group compared to the lesion group （P 〈 0.01）. CONCLUSION： Agmatine can substantially increase BDNF levels in the rat brainstem after facial nerve injury.
基金the National Natural Science Foundation of China, No.30060034the Natural Science Foundation of Jiangxi Province, No.0140126+2 种基金Jiangxi Provincial Health Bureau, No.20052039Jiujiang Municipal Guidance Plan Program, No.200447Jiujiang University Key Program, No.05kj25
文摘Changes of brain-derived neurotrophic factor （BDNF） expression reflect function of nerve cells; meanwhile, they play a significant role in researching interventions on plerosis of nerve injury. OBJECTIVE： To observe and compare the effects on changes of BDNF expression in rats with spinal cord injury between microencapsulated sciatic nerve cells of rabbits and only transplanting sciatic nerve cells of rabbits. DESIGN： Randomized controlled animal study. SETTING： Medical School of Jiujiang College. MATERIALS： The experiment was carried out in the Medical Science Researching Center, Jiujiang College from May 2004 to May 2006. A total of 90 healthy adult SD rats, weighing 250 - 300 g, of either gender; and 10 rabbits, weighing 2.0 - 2.5 kg, of either gender, were provided by Jiangxi Experimental Animal Center. METHODS： Sciatic nerve tissue of rabbits was separated to make cell suspension, After centrifugation, suspension was mixed with 15 g/L alginate saline solution and ejaculated to 20 mmol/L barium chloride saline solution by double-cavity ejaculator. The obtained cell microcapsules were suspended in saline. Rats were randomly divided into microencapsulated group, only suspension group, and only injured group with 30 animals in each group. After anesthesia, T10 spinous process and vertebra lamina of rats in the former two groups were exposed. Spinal cord tissue in 2-mm length was removed from rats by spinal cord right hemi-section. The gelatin sponges with the size of 2 mm × 2 mm × 2 mm were grafted as filing cage, and absorbed 10 μL microencapsulated sciatic nerve cells of rabbit in the microencapsulated group and 10 μL sciatic nerve cells of rabbits in the only suspension group; respectively. No graft was placed in the only injured group. MAIN OUTCOME MEASURES： On the 1^st, 3^rd, 7^th, 14^th and 28^th days after operation, immunohistochemistry （SABC technique） was used to detect distribution and amount of positive-reactive neurons in BDNF of spinal cord samples which were selected as 2 cm away from the injured surface. RESULTS： All the 90 rats were involved in the final analysis. Masses of brown-yellow particles were found in the microencapsulated group, and most of them were distributed in the spinal cord anterior horn neurons and glial cells. The positive-reactive neuron particles were also found in the white matter and gray matter. On the 3^rd, 7^th, 14^th and 28^th days after operation, amount of positive-reactive neurons in BDNF in the microencapsulated group was higher than that in the only injured group （P 〈 0.01） and only suspension group （P 〈 0.05）. CONCLUSION： After transplanting microencapsulated nerve cell suspension into injured spinal cord of rats, distribution and amount of positive-reactive neurons in BDNF of local samples at injured surface are increased remarkably as compared with those by using tissue cell transplantation.
基金supported by the National Natural Science Foundation of China,No.31320103906(to TB)
文摘Parkinson＇s disease is a progressive neurological disease characterized by the degeneration of dopaminergic neurons in the substantia nigra.A highly similar pattern of neurodegeneration can be induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine（MPTP） or 1-methyl-4-phenylpyridinium ion（MPP＋）,which cause the death of dopaminergic neurons.Administration of MPTP or MPP＋ results in Parkinson＇s disease-like symptoms in rodents.However,it remains unclear whether intracerebroventricular MPP＋ administration affects neurogenesis in the substantia nigra and subgranular zone or whether brain-derived neurotrophic factor alters the effects of MPP＋.In this study,MPP＋（100 nmol） was intracerebroventricularly injected into mice to model Parkinson＇s disease.At 7 days after administration,the number of bromodeoxyuridine（Brd U）-positive cells in the subgranular zone of the hippocampal dentate gyrus increased,indicating enhanced neurogenesis.In contrast,a reduction in Brd U-positive cells was detected in the substantia nigra.Administration of brain-derived neurotrophic factor（100 ng） 1 day after MPP＋ administration attenuated the effect of MPP＋ in the subgranular zone and the substantia nigra.These findings reveal the complex interaction between neurotrophic factors and neurotoxins in the Parkinsonian model that result in distinct effects on the catecholaminergic system and on neurogenesis in different brain regions.
文摘Objective:To explore the protective mechanisms of nerve growth factor (NGF) on spinal cord injury (SCI) and provide theoretical basis for its clinical application. Methods: The SCI of Wistar rats was done by Allens weight dropping way by a 10 g×2.5 cm impact on the posterior of spinal cord T 8. NGF (3 g/L, 20 μl) or normal saline was injected through catheter into subarachnoid space 2, 4, 8, 12 and 24 h after SCI. The expression of N-methyl-D-asparate receptor 1 (NMDAR 1) and neuronal constitutive nitric oxide synthase (ncNOS) mRNA in rat spinal cord was detected by in situ hybridization. Results: Abnormal expression of NMDAR 1 and ncNOS mRNA appeared in spinal ventral horn motorneuron in injured rats, as compared with that in control group. The expression of NMDAR 1 and ncNOS mRNA in NGF group was significantly lower than that in saline group (P<0.01). Conclusion: NGF can protect spinal cord against injury in vivo. One of the mechanisms is that NGF can prohibit NMDAR 1 and nitric oxide (NO) production after spinal cord injury.
文摘Objective To investigate the regulatory effects of nerve growth factor （NGF） on basal and capsaicin-induced release of neuropeptide substance P （SP） in primary cultured embryonic rat dorsal root ganglion （DRG） neurons. Methods DRGs were dissected from 15-day-old embryonic Wistar rats. DRG neurons were dissociated and cultured, and then exposed to different concentrations of NGF （10 ng/mL, 30 ng/mL, or 100 ng/mL） for 72 h. The neurons cultured in media without NGF served as control. RT-PCR were used for detecting the mRNAs of SP and vanilloid receptor 1 （VR1） in the DRG neurons. The SP basal and capsaicin （100 nmol/L）-induced release in the culture were measured by radioimmunoassay （RIA）. Results SP mRNA and VR1 mRNA expression increased in primary cultured DRG neurons in a dose-dependent manner of NGF. Both basal release and capsaicin-evoked release of SP increased in NGF-treated DRG neurons compared with in control group. The capsaicin-evoked release of SP also increased in a dose-dependent manner of NGF. Conclusion NGF may promote both basal release and capsaicin-evoked release of SP. NGF might increase the sensitivity of nociceptors by increasing the SP mRNA or VR1 mRNA.
基金This work was supported by the Key Program of Natural Science Foundation of Yunnan Province, China （No. 2003C0010Z）.
文摘Objective To investigate the expression of nerve growth factor （NGF） and glial cell line-derived neurotrophic factor （GDNF） in monkeys of resuscitation after selective cerebral ultraprofound hypothermia and blood flow occlusion. Methods The monkeys were immediately removed brain after death in operation of group A （identical temperature perfusion group） and group B （ultraprofound hypothermia perfusion group）. Immunohistochemical technique was used to determine frontal cellular expression of NGF and GDNF. Statistics were analyzed by ANOVA analyses with significance level at P 〈 0.05. Results The expressions of NGF and GDNF in the group B were significantly higher than those in the group A （P 〈 0.05）. Conclusion NGF and GDNF increased significantly in the monkeys of resuscitation after selective cerebral ultraprofound hypothermia and blood flow occlusion. It may be a protective mechanism for neuron survival and neural function recovery.
文摘Objective: to obtain the high purified and active nerve growth factor (NGF) from mouse submaxillary glands. Methods: NGF was prepared from mouse submaxillary glands by the way of elution with CM 52 column. The molecular weight and purification of NGF were detected by SDS-PAGE polyacrylamide gel electrophoresis. The biological activity of NGF was verified thorough culturing DRG. Results: About 14 kDa stained band was observed on SDS-PAGE and it promoted proliferation of dorsal root gang lia (DRG). Conclusion: Good quality of NGF could be obtained with these methods.
基金supported by Science and Technology Research Project of Jilin Provincial Department of Education,No.JJKH20220072KJ(to XL)Science and Technology Development Program of Jilin Province,No.20200201495JC(to YL)。
文摘The integrity of retinal ganglion cells is tightly associated with diabetic macular degeneration that leads to damage and death of retinal ganglion cells,affecting vision.The major clinical treatments for diabetic macular edema are anti-vascular endothelial growth factor drugs and laser photocoagulation.However,although the macular thickness can be normalized with each of these two therapies used alone,the vision does not improve in many patients.This might result from the incomplete recovery of retinal ganglion cell injury.Therefore,a prospective,non-randomized,controlled clinical trial was designed to investigate the effect of anti-vascular endothelial growth factor drugs combined with laser photocoagulation on the integrity of retinal ganglion cells in patients with diabetic macular edema and its relationship with vision recovery.In this trial,150 patients with diabetic macular edema will be equally divided into three groups according to therapeutic methods,followed by treatment with anti-vascular endothelial growth factor drugs,laser photocoagulation therapy,and their combination.All patients will be followed up for 12 months.The primary outcome measure is retinal ganglion cell-inner plexiform layer thickness at 12 months after treatment.The secondary outcome measures include retinal ganglion cell-inner plexiform layer thickness before and 1,3,6,and 9 months after treatment,retinal nerve fiber layer thickness,best-corrected visual acuity,macular area thickness,and choroidal thickness before and 1,3,6,9,and 12 months after treatment.Safety measure is the incidence of adverse events at 1,3,6,9,and 12 months after treatment.The study protocol hopes to validate the better efficacy and safety of the combined treatment in patients with diabetic macula compared with the other two monotherapies alone during the 12-month follow-up period.The trial is designed to focus on clarifying the time-effect relationship between imaging measures related to the integrity of retinal ganglion cells and best-corrected visual acuity.The trial protocol was approved by the Medical Ethics Committee of the Affiliated Hospital of Beihua University with approval No.(2023)(26)on April 25,2023,and was registered with the Chinese Clinical Trial Registry(registration number:ChiCTR2300072478,June 14,2023,protocol version:2.0).
基金supported by the National Natural Sclence Foundation of China in 2021No.82171213+1 种基金the Natural Science Foundation of Fujian Province in 2019No.2019J01289 (both to DSL)
文摘The trigeminal root entry zone is the zone at which the myelination switches from peripheral Schwann cells to central oligodendrocytes.Its special anatomical and physiological structure renders it susceptible to nerve injury.The etiology of most primary trigeminal neuralgia is closely related to microvascular compression of the trigeminal root entry zone.This study aimed to develop an efficient in vitro model mimicking the glial environment of trigeminal root entry zone as a tool to investigate the effects of glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor on the structural and functional integrity of trigeminal root entry zone and modulation of cellular interactions.Primary astrocytes and Schwann cells isolated from trigeminal root entry zone of postnatal rats were inoculated into a two-well silicon culture insert to mimic the trigeminal root entry zone microenvironment and treated with glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor.In monoculture,glial cell line-derived neurotrophic factor promoted the migration of Schwann cells,but it did not have effects on the migration of astrocytes.In the co-culture system,glial cell line-derived neurotrophic factor promoted the bidirectional migration of astrocytes and Schwann cells.Brain-derived neurotrophic factor markedly promoted the activation and migration of astrocytes.However,in the co-culture system,brain-derived neurotrophic factor inhibited the migration of astrocytes and Schwann cells to a certain degree.These findings suggest that glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor are involved in the regulation of the astrocyte-Schwann cell interaction in the co-culture system derived from the trigeminal root entry zone.This system can be used as a cell model to study the mechanism of glial dysregulation associated with trigeminal nerve injury and possible therapeutic interventions.
基金supported by the National Natural Science Foundation of China,No.81373754,81102670
文摘Using electroacupuncture and moxibustion to treat peripheral nerve injury is highly efficient with low side effects. However, the electroacupuncture-and moxibustion-based mechanisms underlying nerve repair are still unclear. Here, in vivo and in vitro experiments uncovered one mechanism through which electroacupuncture and moxibustion affect regeneration after peripheral nerve injury. We first established rat models of sciatic nerve injury using neurotomy. Rats were treated with electroacupuncture or moxibustion at acupoints Huantiao （GB30） and Zusanli （ST36）. Each treatment lasted 15 minutes, and treatments were given six times a week for 4 consecutive weeks. Behavioral testing was used to determine the sciatic functional index. We used electrophysiological detection to measure sciatic nerve conduction velocity and performed hematoxylin-eosin staining to determine any changes in the gastrocnemius muscle. We used immunohistochemistry to observe changes in the expression of S100—a specific marker for Schwann cells—and an enzyme-linked immunosorbent assay to detect serum level of nerve growth factor. Results showed that compared with the model-only group, sciatic functional index, recovery rate of conduction velocity, diameter recovery of the gastrocnemius muscle fibers, number of S100-immunoreactive cells,and level of nerve growth factor were greater in the electroacupuncture and moxibustion groups. The efficacy did not differ between treatment groups. The serum from treated rats was collected and used to stimulate Schwann cells cultured in vitro. Results showed that the viability of Schwann cells was much higher in the treatment groups than in the model group at 3 and 5 days after treatment. These findings indicate that electroacupuncture and moxibustion promoted nerve regeneration and functional recovery; its mechanism might be associated with the enhancement of Schwann cell proliferation and upregulation of nerve growth factor.
