AIM: To determine whether etomidate (ET) has a protective effect on retinal ganglion cells (RGCs) injured with hydrogen peroxide (H2O2) and to explore the potential mechanism underlying the antioxidative stress effect of ET. METHODS: Cultured RGCs were identified by double immunofluorescent labeling of microtubule-associated protein 2 and Thy1.1. An injury model of H2O2-induced RGCs oxidative stress was established in vitro. Cells were pretreated with different concentrations of ET (1, 5, and 10 μmol/L) for 4h, followed by further exposure to H2O2 at 1000 μmol/L. Cell counting kit 8 and Annexin V/propidium iodide assays were applied to detect the viabilities and apoptosis rates of the RGCs at 12, 24, and 48h after H2O2 stimulation. The levels of nitric oxide, malondialdehyde, and glutathione in culture media were measured at these time points. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot were performed to observe the effects of ET on the messenger RNA and protein expression of inducible nitric oxide synthase (iNOS), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), glutathione peroxidase 1 and the level of conjugated acrolein in RGCs at 12, 24, and 48h after H2O2 stimulation and in the retina at 12h after optic nerve transection (ONT). RESULTS: The applications of 5 and 10 μmol/L of ET significantly increased the viability of RGCs. Results from qRT-PCR indicated a decrease in the expression of iNOS and an increase in the expressions of Nrf2 and HO-1 in ET-pretreated RGCs at 12, 24 and 48h after H2O2 stimulation, as well as in ET-treated retinas at 12h after ONT. Western blot analysis revealed a decrease in the expression of iNOS and levels of conjugated acrolein, along with an increase in the expressions of Nrf2 and HO-1 in ET-pretreated RGCs in vitro and ET-treated retinas in vivo. CONCLUSION: ET is a neuroprotective agent in primary cultured RGCs injured by H2O2. The effect of ET is dose-dependent with the greatest effect being at 10 μmol/L. ET plays an antioxidant role by inhibiting iNOS, up-regulating Nrf2/HO-1, decreasing the production of acrolein, and increasing the scavenge of acrolein.

Objective:To observe the protective effect of etomidate (ET) on cultured retinal ganglion cells (RGC) with mechanical injury in vitro.Methods:New Sprague-Dawley rat RGC was cultured in vitro and identified by double immunofluorescent labeling of Thy1.1 and microtubule associated protein 2. The cultured primary cells were randomly divided into control group, RGC scratch group, ET low dose group (1 μmol/L), ET medium dose group (5 μmol/L) and ET high dose group (10 μmol/L). The RGC mechanical injury model was established by using iris knife to culture cells in RGC scratch group and ET group with different concentration. Seven days after modeling, the RGC survival rate of each group was detected by cell count Kit 8 proliferation assay. The apoptosis rate of RGC was detected by Annexin Ⅴ/propyl iodide double staining. Single factor analysis of variance was used to compare the groups. The pairwise comparison between groups was tested by the least significant difference method.Results:The survival rates of RGC in RGC scratch group, ET low dose group, ET medium dose group and ET high dose group were (72.60±2.97)%, (73.73±1.14)%, (79.19±1.79)% and (83.88±0.94)%, respectively. The RGC apoptosis rates of control group, RGC scratch group, ET low dose group, ET medium dose group and ET high dose group were (5.08±0.17)%, (18.67±1.24)%, (17.96±0.74)%, (15.11±0.56)% and (11.67±1.32)%, respectively. Comparison of RGC survival rate between groups: compared with RGC scratch group, the cell survival rate of ET low-dose group, ET medium-dose group and ET high-dose group was increased, and the difference between RGC scratch group and ET low-dose group was not statistically significant ( P=0.728); the differences between RGC scratch group, ET medium dose group and ET high dose group were statistically significant ( P<0.001); the difference between ET medium dose group and ET high dose group was statistically significant ( P=0.002). Comparison of apoptosis rate of RGC among groups: the apoptosis rate of RGC scratch group was significantly higher than that of control group, the difference was statistically significant ( P<0.001). Compared with RGC scratch group, the apoptosis rate of ET low-dose group, ET medium-dose group and ET high-dose group was decreased, and there was no statistical significance between RGC scratch group and ET low-dose group ( P=0.869). The differences of apoptosis rate between RGC scratch group, ET medium dose group and ET high dose group were statistically significant ( P<0.05). The difference of apoptosis rate between ET medium dose group and ET high dose group was statistically significant ( P=0.007). Conclusion:ET has neuroprotective effect on RGC cultured in vitro with mechanical injury, and the protective effect increases with the increase of ET dose in a certain range.

目的 观察抗胶质纤维酸性蛋白(GFAP)抗体阳性4例患者的临床特征.方法 回顾性研究.2017年1月至2021年12月于空军军医大学西京医院眼科和神经内科住院治疗的抗GFAP抗体阳性患者4例纳入研究,包括视神经炎(ON)3例,脊髓/脑病变1例.患者均为女性;平均年龄35岁.3例ON患者接受最佳矫正视力(BCVA)、光相干断层扫描、视觉诱发电位、头颅和眼眶核磁共振成像(MRI)检查;1例脊髓/脑病变患者行头颅、颈椎、胸椎MRI检查.所有患者接受血清脱髓鞘抗体检测,脊髓/脑病变者同时接受脑脊液脱髓鞘抗体检测.ON患者急性期给予静脉滴注甲泼尼龙琥珀酸钠治疗;脊髓/脑病变患者给予糖皮质激素及免疫抑制剂治疗.结果 ON患者首发症状均为右眼突发性视物模糊伴眼球转动痛;BCVA分别为手动/眼前、0.2和0.12;血清抗GFAP抗体均为阳性;MRI检查,1例视神经毛糙、增粗.BCVA手动/眼前者,出院时BCVA提高至数指/30cm;2例BCVA无变化.出院2～3年后电话随访BCVA均提高至0.6以上.脊髓/脑病变患者无视神经受累,首发症状为肢体麻木无力及抽搐;血清抗GFAP抗体阴性,脑脊液抗GFAP抗体阳性;MRI检查,小脑及脊髓硬膜均有强化.出院时症状缓解;出院后电话随访症状消失.结论 抗GFAP抗体阳性患者多见于中青年女性;以单眼ON多见,表现为突发性视物模糊伴眼球转动痛,血清抗GFAP抗体阳性,个别患者MRI检查显示视神经毛糙及增粗,对糖皮质激素治疗敏感,预后较好.

Abstract Background Our previous research provided an experimental basis for etomidate (ET) to treat optic nerve (ON) injuries. However, the mechanism of ET action in anti-oxidative stress remains unclear and requires further investigation. This study aimed to determine whether ET has a protective effect on retinal ganglion cells (RGCs) injured by H2O2 and to explore ET's possible anti-oxidative stress mechanism. Methods Cultured RGCs were identified using the double immunofluorescent labeling of Thy1.1 and Microtubule association protein-2. An H2O2-induced RGCs oxidative stress injury model was established in vitro. Cells were pretreated with different concentrations of ET (1, 5, and 10 µmol/L) for 4 hours, followed by further exposure to H2O2 at 1000 µmol/L. CCK-8 and Annexin V/PI assay were applied to detect the RGCs viability and apoptosis rate at 12, 24, and 48 hours after H2O2 stimulation. The levels of nitric oxide (NO), malondialdehyde (MDA), and glutathione (GSH) in culture media were measured at these time points. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot were used to observe the effects of ET on the mRNA and protein expressions of nitric oxide synthase (iNOS), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), glutathione peroxidase1 (GPX1) and acrolein in RGCs at 12, 24, and 48 hours after H2O2 stimulation and in the retina at 12 hours after optic nerve transection (ONT). Results The viability of RGCs was increased significantly with 5 and 10 µM of ET. The qRT-PCR showed that iNOS expression was decreased and Nrf2 and HO-1 expressions were increased in RGCs and retinas with ET. The Western blot showed that the expressions of iNOS and acrolein were decreased, and the expressions of Nrf2 and HO-1 were increased in RGCs with ET at 12, 24, and 48 hours after H2O2 stimulation and in the retina with ET at 12 hours after ONT. Conclusion ET has a neuroprotective effect in primary cultured RGCs injured by H2O2. The effect of ET was dose-dependent being greatest at 10 µM. ET plays an antioxidant role by inhibiting iNOS, up-regulating Nrf2/HO-1, decreasing the production of acrolein, and increasing acrolein scavenging.

Dear Editor, The optic nerve,which belongs to the central nervous system(CNS),cannot regenerate when injured in adult mammals.1 Up to now,no readily translatable measures are available for repairing a severely injured optic nerve.Herein we demonstrated that ciliary neurotrophic factor(CNTF)-chitosan enabled the reconstruction and functional recovery of the adult rat visual system,thus shedding light on the clinical potential for repairing the severely injured optic nerve.

This study was designed to see the expression of toll-like receptor 4 (TLR4) and downstream molecules including myeloid differentiation factor 88 (MyD88) and interleukin 1-β (IL-1β) in the spinal cord as peripheral nerve injury recovered in mice. We established a model of femoral nerve injury (FNI) in C57BL/6 mice by transection of the motor branch of the femoral nerve, followed by retrograde labeling to show the according motor neurons in the anterior horn of the spinal cord pars lumbar. We observed the motor function recovery of the injured hind limbs using behavioral tests. The expression of TLR4, MyD88, and IL-1β was examined by immunofluorescent staining and western blot. According to the behavior test, the FNI animals fully recovered within 6–8 weeks. TLR4, MyD88, and IL-1β were expressed in the ventral horn of the spinal cord both at 72 h till 6 weeks after the femoral nerve transection surgery, and these proteins were mostly co-localized with neurons. IL-1β also tended to rise in the same surgery groups, but more intimate with microglia surrounding nearby retrograde labeled neurons. And western blot results were consistent with histological findings. The results indicate that peripheral nerve injury may induce innate immune reactions of the central neurons and critical signaling like TLR4/MyD88 in the spinal cord may reflect the recovery of the injury. These findings suggest that peripheral nerve injury triggered the TLR4/MyD88 signal in the soma of spinal neurons may be involved in function and nerve restoration through neuron-glia crosstalk.

Our previous study has shown that the negative co-stimulatory molecule B7-H4 is constitutively expressed on human bone marrow-derived mesenchymal stem cells (MSCs) and mediates their immunomodulatory effect on T cells in vitro. However, whether B7-H4 on MSCs can be responsible for their immunomodulation in vivo has not been clarified. The present study investigated the immunomodulatory role and mechanism of B7-H4 on mouse mesenchymal stem cell (MSCs) in the development of experimental autoimmune encephalomyelitis (EAE). Murine MSC C3H/10T1/2 (C3H10) cells were transfected with B7-H4-specific shRNA to silence B7-H4 expression (C3H10-B7H4). The effects of C3H10-B7H4 cells on splenocyte proliferation and cell cycling as well as cytokine responses were examined.We found that B7-H4 silencing mitigated the immune-inhibitory effect of C3H10 cells on PHA-stimulated splenocyte activation and proliferation as well as IL-2, IL-17 and IFN-gamma responses. Female C57BL/6 mice were injected with myelin oligodendrocyte glycoprotein peptide (MOG35-55) to induce EAE, then infused with C3H10-B7H4, C3H10-NC (C3H10 transfected with negative control shRNA) or C3H10 cells. The pathological changes of the injured spinal cord were analyzed by hematoxylin and eosin (H&E) staining, Luxol fast blue (LFB) staining and immunofluorescence. Infusion with C3H10 or C3H10-NC, but not C3H10-B7H4 cells, dramatically slowed the development of EAE, and reduced the severity and degree of inflammatory infiltrates, demyelination, and axonal damages. The plasma levels of interleukin-2 (IL-2), IL-17, interferon-gamma (IFN-gamma), and IL-4 in the different groups of mice were examined. Infusion with C3H10 or C3H10-NC cells significantly decreased the plasma levels of IL-2, IL-17 and IFN-gamma in EAE mice, but infusion with C3H10-B7H4 cells only slightly reduced pro-inflammatory cytokine responses in mice. Taken together,

Alterations in phospholipids have long been associated with spinal cord injury (SCI). However, their specific roles and signaling cascades in mediating cell death and tissue repair remain unclear. Here we investigated whether alterations of cardiolipin (CL), a family of mitochondrion-specific phospholipids, play a crucial role in mitochondrial dysfunction and neuronal death following SCI. Lipidomic analysis was used to determine the profile of CL alteration in the adult rat spinal cord following a moderate contusive SCI at the 10th thoracic (T10) level. Cellular, molecular, and genetic assessments were performed to determine whether CL alterations mediate mitochondrial dysfunction and neuronal death after SCI, and, if so, whether reversing CL alteration leads to neuroprotection after SCI. Using lipidomic analysis, we uncovered CL alterations at an early stage of SCI. Over 50 distinct CL species were identified, of which 50% showed significantly decreased abundance after SCI. The decreased CL species contained mainly polyunsaturated fatty acids that are highly susceptible to peroxidation. In parallel, 4-HNE, a lipid peroxidation marker, significantly increased after SCI. We found that mitochondrial oxidative stress not only induced CL oxidation, but also resulted in CL loss by activating cPLA 2 to hydrolyze CL. CL alterations induced mitochondrial dysfunction and neuronal death. Remarkably, pharmacologic inhibition of CL alterations with XJB-5-131, a novel mitochondria-targeted electron and reactive oxygen species scavenger, reduced cell death, tissue damage and ameliorated motor deficits after SCI in adult rats. These findings suggest that CL alteration could be a novel mechanism that mediates injury-induced neuronal death, and a potential therapeutic target for ameliorating secondary SCI.

Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is related to anti-oxidative stress is not clear. To reveal its mechanism, we established the optic nerve transection injury model by transecting 1 mm behind the left eyeball of adult male Sprague-Dawley rats. The rats received an intraperitoneal injection of etomidate (4 mg/kg) once per day for 7 days. The results showed that etomidate significantly enhanced the number of retinal ganglion cells retrogradely labeled with Fluorogold at 7 days after optic nerve transection. Etomidate also significantly reduced the levels of nitric oxide and malonaldehyde in the retina and increased the level of glutathione at 12 hours after optic nerve transection. Thus, etomidate can protect retinal ganglion cells after optic nerve transection in adult rats by activating an anti-oxidative stress response. The study was approved by the Animal Ethics Committee at Air Force Medical University, China (approval No. 20180305) on March 5, 2018.

AIM: To investigate the effect of cardiovascular risk factors on the occurrence of nonarteritic anterior ischemic optic neuropathy(NAION)and visual functions of the patients.METHODS: Sixty-eight patients diagnosed as initial ipsilateral NAION(68 eyes)in NAION group and another 68 patients(68 eyes)matched in age, gender and systemic diseases in Control group were selected from June 2014 to June 2016 were enrolled in this study and evaluated for their levels of homocysteine(Hcy), blood lipids, folic acid and vitamin B12, as well as carotid Doppler ultrasonography. The visual functions were also examined in patients with NAION.RESULTS: The levels of Hcy(24.8±13.9μmol/L), total plasma cholesterol(4.5±1.0mmol/L), triglyceride(2.0±0.9 mmol/L)and low-density lipoprotein(2.9±0.8mmol/L)in NAION patients were significantly higher(P<0.05)than those in Control group(11.1±8.2μmol/L, 3.8±0.7mmol/L, 1.5±0.5mmol/L and 2.3±0.5mmol/L)while the level of vitamin B12 decreased significantly(315.6 ±214.5pg/mL, P<0.05)in NAION group in comparison with those(467.9±198.2pg/mL)in Control group. However, no significant differences in the artery resistance and inner diameter of the internal carotid were detected between the two groups. The mean deviation(MD)of the visual field was 16.6±7.5dB in NAION group. The levels of Hcy, vitamin B12, folic acid and blood lipid and the presence of systemic diseases were not the risk factors for the visual field damage in NAION patients. MD value was associated with the amplitude and peak latency of P100 waves.CONCLUSION: Hyperhomocysteinemia, hyperlipidemia and low vitamin B12 are the risk factors of in NAION patients. These risk factors, however, are not related to the extent of visual field damage. To some extent, the amplitude and peak latency of visual evoked potentials can reflect the extent of visual field damage.

Prenatal alcohol exposure (PAE) could lead to developmental disorders of the central nervous system (CNS) and mental retardation. Toll-like receptor (TLR) 4 plays an important role in PAE-induced neurodevelopmental defects. However, how PAE affects TLR4 response in the brain remains controversial. Using a moderate PAE model by feeding pregnant rats with liquid ethanol diet, we investigated the TLR4-mediated response to intraventricular injection of lipopolysaccharide (LPS) in the hippocampus of PEA rats at postnatal day (PND) 30. The results showed that PAE significantly up-regulated the expression of Toll-Interleukin-1 Receptor (TIR)-domain-containing adaptor protein inducing interferon (IFN)-β (TRIF), TNF-α, and IL-1β in the rat hippocampus in the absence of LPS, indicated by western blot assay. LPS treatment dramatically up-regulated the expressions of TLR4 and its downstream molecules in the hippocampus of paired-food and control groups. But no such significant changes of those molecules were found in the hippocampus of PAE animals. Moreover, the LPS stimulation even down-regulated the levels of TLR4 and TRIF in the PAE group. These data suggest that the relatively moderate level of PAE may lead to a mild neuroinflammation and a suppression of TLR4-mediated response to LPS in the hippocampus of young rats. As innate immunity plays crucial roles in CNS development, moderate PAE-induced suppression of TLR4-mediated response may serve as a new candidate mechanism of CNS developmental defects.

Cell therapy has been shown to be a key clinical therapeutic option for central nervous system diseases or damage. Standardization of clinical cell therapy procedures is an important task for professional associations devoted to cell therapy. The Chinese Branch of the International Association of Neurorestoratology (IANR) completed the first set of guidelines governing the clinical application of neurorestoration in 2011. The IANR and the Chinese Association of Neurorestoratology (CANR) collaborated to propose the current version “Clinical Cell Therapy Guidelines for Neurorestoration (IANR/CANR 2017)”. The IANR council board members and CANR committee members approved this proposal on September 1, 2016, and recommend it to clinical practitioners of cellular therapy. These guidelines include items of cell type nomenclature, cell quality control, minimal suggested cell doses, patient-informed consent, indications for undergoing cell therapy, contraindications for undergoing cell therapy, documentation of procedure and therapy, safety evaluation, efficacy evaluation, policy of repeated treatments, do not charge patients for unproven therapies, basic principles of cell therapy, and publishing responsibility.

Purpose: This study's aim was to investigate the beneficial effects of branched-chain amino acids (BCAAs) on the neuronal survival and axon regeneration of retinal ganglion cells (RGCs) after optic nerve (ON) transection. Method: The experimental rats received daily BCAA injections through the caudal vein after left intra-orbital ON transection. Neuroprotection was evaluated by counting Fluorogold-labeled RGCs. The role of mammalian target of rapamycin (mTOR) pathway activation in promoting RGC survival was studied after rapamycin administration. Moreover, a peripheral nerve (PN) graft was transplanted onto the transected ON to study the effects of BCAAs on axon regeneration of injured RGCs. Results: Our results showed that BCAAs alleviated the death of RGCs 7 and 14 days after ON transection, accompanied by an activation of mTOR pathway in RGCs. Blocking mTOR pathway with rapamycin eliminated such neuroprotective effects of BCAAs. Moreover, BCAAs also promoted axon regeneration of injured RGCs into a PN graft. Conclusion: Our results suggest a neuroprotection of BCAAs through the activation of mTOR pathway. BCAAs also have a beneficial effect on axon regeneration of injured RGCs. Therefore, BCAAs could be considered for the clinical treatment of ON injury.

患者女,18岁.2010年9月因头枕部外伤致意识丧失入院.醒后发现左眼内斜、眼球运动障碍、视力下降伴口角右偏.眼眶CT检查未见异常;头颅MRI检查显示小脑蚓部出血致双侧小脑半球、第四脑室及背侧脑桥受压变形(图1).伤后10 d行颅内血肿清除手术.手术后上述症状无改善且逐渐出现左眼睑闭合不全、视力逐渐下降.

Optic neuropathy refers to disorders involving the optic nerve (ON). Any damage to ON or ON-deriving neurons, the retinal ganglion cells (RGCs), may lead to the breakdown of the optical signal transmission from the eye to the brain, thus resulting in a partial or complete vision loss. The causes of optic neuropathy include trauma, ischemia, inflammation, compression, infiltration, and mitochondrial damages. ON injuries include primary and secondary injuries. During these injury phases, various factors orchestrate injured axons to die back and become unable to regenerate, and these factors could be divided into two categories: extrinsic and intrinsic. Extrinsic inhibitory factors refer to the environmental conditions that influence the regeneration of injured axons. The presence of myelin inhibitors and glial scar, lack of neurotrophic factors, and inflammation mediated by injury are regarded as these extrinsic factors. Extrinsic factors need to trigger the intracellular signals to exert inhibitory effect. Proper regulation of these intracellular signals has been shown to be beneficial to ON regeneration. Intrinsic factors of RGCs are the pivotal reasons that inhibit ON regeneration and are closely linked with extrinsic factors. Intracellular cyclic adenosine monophosphate (cAMP) and calcium levels affect axon guidance and growth cone response to guidance molecules. Many genes, such as Bcl-2, PTEN, and mTOR, are crucial in cell proliferation, axon guidance, and growth during development, and play important roles in the regeneration and extension of RGC axons. With transgenic mice and related gene regulations, robust regeneration of RGC axons has been observed after ON injury in laboratories. Although various means of experimental treatments such as cell transplantation and gene therapy have achieved significant progress in neuronal survival, axonal regeneration, and restoration of the visual function after ON injury, many unresolved scientific problems still exist for their clinical applications. Therefore, we still need to overcome hurdles before developing effective therapy to treat optic neuropathy diseases in patients.

The optic nerve belongs to the central nervous system (CNS).Because of the lack of neurotrophic factors in the microenvironment of the CNS and the presence of myelin and glial scar-related inhibitory molecules,and the inherent low renewal potentials of CNS neurons comparing to the peripheral nerve system,it is difficult to spontaneously regenerate the optic nerve after injury.Protecting damaged retinal ganglion cells (RGCs),supplementing neurotrophic factor,antagonizing axon regeneration inhibitory factor,and regulating the inherent regeneration potential of RGCs can effectively promote the regeneration and repair of optic nerve.Basic research has made important progress,including the restoration of visual function,but there are still a lot of unsolved problems in clinical translation of these achievements,so far there is no ideal method of treatment of optic nerve injury.Therefore,it is rather urgent to strengthen the cooperation between basic and clinical research,to promote the transformation of basic research to the clinical applications as soon as possible,which will change the unsatisfactory clinical application status.

Sphingosine-1-phosphate and its structural analog FTY720 (fingolimod) are important in the inhibition of osteoclast differentiation and bone resorption, however, it remains unknown whether they enhance osteogenic differentiation of the bone marrow mesenchymal stem cells (BM‑MSCs). The present study investigated the effect of FTY720 on the osteogenic differentiation of BM‑MSCs from the femurs of the ovariectomized (OVX) rats. Three different concentrations (1, 10 and 100 nM) of FTY720 were demonstrated to markedly upregulate mRNA expression levels of Runt‑related transcription factor 2 (Runx2) and Sp7 transcription factor (Sp7) at 2 weeks, and alkaline phosphatase (ALP) at 3 weeks. The osteocalcin (OCN) expression was similar at weeks 2 and 3. The protein expression levels of Runx2, Sp7, OCN and ALP induced by three different concentrations of FTY720 were higher than those in the control groups at 3 weeks in the OVX and sham groups. The findings of the current study suggested a beneficial effect of FTY720 on bone formation in OVX rats, and provided a potential therapeutic method of FTY720 to prevent alveolar bone resorption in patients with post‑menopausal osteoporosis.

Peripheral nerve (PN) grafts can be used to bridge tissue defects in the CNS. Using a PN-to-optic nerve (ON) graft model, we combined gene therapy with pharmacotherapy to promote the long-distance regeneration of injured adult retinal ganglion cells (RGCs). Autologous sciatic nerve was sutured onto the transected ON and the distal end immediately inserted into contralateral superior colliculus (SC). Control rats received intraocular injections of saline or adeno-associated virus (AAV) encoding GFP. In experimental groups, three bi-cistronic AAV vectors encoding ciliary neurotrophic factor (CNTF) were injected into different regions of the grafted eye. Each vector encoded a different fluorescent reporter to assess retinotopic order in the regenerate projection. To encourage sprouting/synaptogenesis, after 6weeks some AAV–CNTF injected rats received an intravitreal injection of recombinant brain-derived neurotrophic factor (rBDNF) or AAV–BDNF. Four months after surgery, cholera toxin B was used to visualize regenerate RGC axons. RGC viability and axonal regrowth into SC were significantly greater in AAV–CNTF groups. In some cases, near the insertion site, regenerate axonal density resembled retinal terminal densities seen in normal SC. Complex arbors were seen in superficial but not deep SC layers and many terminals were immunopositive for presynaptic proteins vGlut2 and SV2. There was improvement in visual function via the grafted eye with significantly greater pupillary constriction in both AAV–CNTF+BDNF groups. In both control and AAV–CNTF+rBDNF groups the extent of light avoidance correlated with the maximal distance of axonal penetration into superficial SC. Despite the robust regrowth of RGC axons back into the SC, axons originating from different parts of the retina were intermixed at the PN graft/host SC interface, indicating that there remained a lack of order in this extensive regenerate projection.

To mimic multilevel nerve root compression and intervertebral foramina stenosis in human, we established a new animal model of the chronic compression of unilateral multiple lumbar DRGs (mCCD) in the rat. A higher occurrence of signs of spontaneous pain behaviors, such as wet-dog shaking and spontaneous hind paw shrinking behaviors, was firstly observed from day 1 onward. In the meantime, the unilateral mCCD rat exhibited significant bilateral hind paw mechanical and cold allodynia and hyperalgesia, as well as a thermal preference to 30°C plate between 30 and 35°C. The expression of activating transcription factor 3 (ATF3) was significantly increased in the ipsilateral and contralateral all-sized DRG neurons after the mCCD. And the expression of CGRP was significantly increased in the ipsilateral and contralateral large- and medium-sized DRG neurons. ATF3 and CGRP expressions correlated to evoked pain hypersensitivities such as mechanical and cold allodynia on postoperative day 1. The results suggested that bilateral neuropathy of primary sensory neurons might contribute to bilateral hypersensitivity in the mCCD rat.

We aimed to investigate whether peripheral low-dose lipopolysaccharide (LPS) induces the breakdown of the blood–brain barrier (BBB) and/or the activation of toll-like receptor 4 (TLR4) in the neonatal rat brain. Neonatal rats received intraperitoneal injections of low-dose LPS (0.3 mg/kg∙bw), and the BBB compromise was detected by Evans Blue extravasation and electron microscopy. Meanwhile, TLR4, adaptin myeloid differentiation factor 88 (MyD88), nuclear transcription factor kappa-B (NF-κB) p50 and tumor necrosis factor alpha (TNFα) in the neonatal rat brain were determined by quantitative real-time polymerase chain reaction (PCR) and Western Blot. Immunohistochemistry was used to determine the distribution and activation of microglia in the brain after LPS administration. It was demonstrated that Evans Blue extravasation was not observed in the brain parenchyma, and that tight junctions of cerebral endothelial cells remained intact after systemic injections of LPS in neonatal rats. Although intracerebroventricular injections of LPS activated microglia and up-regulated the expression of TLR4, MyD88, NF-κB p50 and TNFα in the neonatal rat brain, systemic LPS did not induce these responses. These findings indicate that while the neonatal rat brain responds to the direct intra-cerebral administration of LPS through robust TLR4 activation, systemic low-dose LPS does not induce the innate immune reaction or compromise the BBB in neonatal rats.