Tauroursodeoxycholic acid treats spinal cord injury by reducing apoptosis of spinal cord neurons under glucose and oxygen deprivation / 中国组织工程研究

BACKGROUND:Tauroursodeoxycholic acid is a hydrophilic bile acid derivative that has neuroprotective effects in a variety of neurological disease models.However,there are few reports on the effects of tauroursodeoxycholic acid on spinal cord injury. OBJECTIVE:To investigate the effect of tauroursodeoxycholic acid on apoptosis of spinal cord neurons under hypoglycemic and hypoxic conditions,as well as the effect on recovery of motor function in mice after spinal cord injury. METHODS:(1)In vitro experiment:Primary spinal cord neurons were isolated from C57 BL/6 mouse embryos at 13.5 days of gestation.After 72 hours of culture,the cells were divided into three groups.In the normal group,cells were cultured in Neurobasal complete medium that was incubated in a CO2 incubator(5%CO2 + 95%air)for 24 hours.In the oxyglucose-deprived group,sugar-free Neurobasal medium was added and incubated in a triple-gas incubator(94%N2+5%CO2+1%O2)for 12 hours,and then the medium was replaced with Neurobasal complete medium and incubated in a CO2 incubator for 12 hours.In the experimental group,the treatment procedure was approximately the same as that in the oxyglucose-deprived group,except that taurodeoxycholic acid was added along with the sugar-free Neurobasal medium.TUNEL staining was used to detect apoptosis,cell counting kit-8 assay was applied to detect cell activity,and immunofluorescence staining was performed to detect cellular β-microtubule protein expression.(2)Animal experiment:Sixty C57 BL/6 mice were randomly divided into sham-operated group,spinal cord injury group and experimental group,with 20 mice in each group.Animal models of T9-T10 spinal cord injury were established using Allen's percussion method in the spinal cord injury group and the experimental group.Starting from the 1st day after modeling,taurodeoxycholic acid solution was given by gavage in the experimental group and normal saline was given by gavage in the sham-operated and spinal cord injury groups once a day for 14 consecutive days.Spinal cord tissue repair was assessed using behavioral and histological methods. RESULTS AND CONCLUSION:In vitro experiment:TUNEL staining,cell counting kit-8 and immunofluorescence staining showed that compared with the normal group,the number of apoptotic cells was higher(P＜0.01),while cell activity and β-microtubule protein expression were lower in the oxyglucose-deprived group(P＜0.01);compared with the oxyglucose-deprived group,the number of apoptotic cells was lower(P＜0.01),while cell activity and β-microtubule protein expression were higher in the experimental group(P＜0.01).Animal experiment:The Basso-Beattie-Bresnahan scores in the open field test and hind limb footprint experiments showed that the mice in the experimental group had better recovery of walking and motor functions than those in the spinal cord injury group.Hematoxylin-eosin staining showed that significant deformities and cavities were observed at the site of spinal cord injury and the number of nerve cells was significantly reduced in the spinal cord injury group.Compared with the spinal cord injury group,the experimental group showed a significant reduction in the area of spinal cord injury,less spinal cord deformity,fewer cavities,and an increase in the number of nerve cells.Immunofluorescence staining showed that the number of neuronal nucleus-labeled neuronal cells in the spinal cord injury group was less than that in the sham-operated group(P＜0.01),and the number of neuronal nucleus-labeled neuronal cells in the experimental group was higher than that in the spinal cord injury group(P＜0.01).To conclude,tauroursodeoxycholic acid could effectively reduce glucose/oxygen deprivation-induced apoptosis of spinal cord neurons and axonal loss,and promote the recovery of motor function in mice with spinal cord injury.

Establishment of a rat model of traumatic brain injury using the modified Feeney's free-fall method / 中国组织工程研究

BACKGROUND:There is less report about mitigating sustained bone grinding injuries during craniotomy based on a model of traumatic brain injury established using the modified Feeney's free-fall method. OBJECTIVE:To modify a modified traumatic brain injury model by altering the opening of the skull window. METHODS:Thirty-six Sprague-Dawley rats were equally randomized into sham group,model group and modified model group.The modified procedure of opening the bone window was used in the modified model group.Six to eight small holes of 0.3-0.5 mm in diameter were punched at the edge of the impact area and the drill was immediately withdrawn without touching the cortex.In the modified model group,the skull window was opened by using the modified method,while the skull window in the model group was opened using the conventional method.The modified model group and model group were established using the Feeney's free-fall method.In the sham group,only the skull window was opened without impact.The modified neurological severity scoring was performed at 1 day after modeling.T2 weighted imaging was performed and T2 values were measured at 1 and 7 days after modeling.Hematoxylin-eosin staining of the brain section was made for histopathological observation at 7 days after modeling.The level of blood viscosity,interleukin-6,interleukin-1β,and tumor necrosis factor-α were determined at 7 days after modeling. RESULTS AND CONCLUSION:Compared with the sham group,the modified neurological severity scores in the model group and modified model group were significantly increased at 1 day after modeling(P＜0.000 1).Meanwhile,the modified neurological severity scores in the modified model group were lower than those in the model group(P＜0.000 1).Compared with the sham group,the T2 values were significantly increased in the model group and modified model group at 1 and 7 days after modeling(P＜0.05),while the T2 values in the modified model group were lower than those in the model group(P＜0.05).Compared with the sham group,the level of blood viscosity,interleukin-6,interleukin-1β and tumor necrosis factor-α were increased in the model group and modified model group at 7 days after modeling(P＜0.05),while the level of interleukin-6 in the modified model group was lower than that in the model group(P＜0.05).To conclude,establishing a modified traumatic brain injury model based on the Feeney's free-fall method provides better controls of injury factors during cranial opening.

Evaluation of non-clinical anxiety disorder models / 药学学报

Anxiety disorders are one of the most common mental disorders in adults, the cause of which derives from a combination of genetics and environmental factors. A series of animal models have been established according to their pathogenesis to measure the level of anxiety or induce anxiety only, and these models have been widely applied in the non-clinical evaluation of anxiolytics. In this review, we present the current trends in the study of anxiety disorders and summarize typical non-clinical anxiety animal models, including models that both measure anxiety levels and induce anxiety, and models that induce anxiety only. This review summarizes the important issues in standardized non-clinical research of anxiety disorders and proposes criteria for the selection of an appropriate R&D model.

Exploration of nonclinical pharmacodynamics evaluation system of Alzheimer's disease / 药学学报

Alzheimer's disease (AD) is the most common neurodegenerative disease that causes dementia among elderly people. The pathogenesis of AD is still unclear, and currently approved drugs only provide symptomatic benefits and do not prevent or delay progressive neurodegeneration. Meanwhile, potential drugs in development are facing great challenges in clinical translation. Therefore, finding effective treatment for the unmet clinical needs of AD is of great economic value and social significance. In this review, we will summarize the current models and pharmacodynamics evaluation methods of anti-AD drug based on the recent studies at home and abroad, and provide reference for drug development in AD at nonclinical stage.

Improvements of motor and cognitive functions in the rats with permanent middle cerebral artery occlusion treated with acupuncture and rota-rod training / 中国针灸

OBJECTIVE@#To explore the effects on the recovery of the motor and cognitive functions of the rats with permanent middle cerebral artery occlusion (pMCAO) after treated with 's three-needle acupuncture at head acupoints combined with rota-rod training.@*METHODS@#A total of 38 male SD rats were randomized into 3 groups, named a sham-operation group (11 rats), a model group (13 rats) and a treatment group (14 rats). The electrocoagulation method was adopted to establish the model of pMCAO on the right cerebrum. Starting from the 1st day after successful modeling, acupuncture was applied to the "three points of intelligence", the "three points of temporal area" and the "three points of brain". Additionally, the rota-rod training was used. Acupuncture was given once a day and the training was three times a day. In the sham-operation group and the model group, empty grasp fixation was performed when acupuncture was applied in the treatment group, and there was no intervention at the rest of the time. There was 1 day of interval after consecutive 6 days of intervention. Totally, the intervention was for 3 weeks. After modeling, the brain section was collected from 3 rats of each group on the 1st day and was stained with TTC to observe the condition of cerebral ischemia. From day 1 to 7, the neurological function score was evaluated. The footprint analysis and rota-rod test were performed on day 1, 7, 14 and 21. The Morris water maze test was performed from day 22 to 26.@*RESULTS@#Compared with the sham-operation group, cerebral ischemia presented obviously, the score of neurological function was increased, the back front distances on the left were increased on day 1, 7 and 14 separately, the revolutions per minute (RPM) of the rota-rod were reduced at each of the above 4 time points, the latency of navigation trial was increased and the movement time percentage in Q3 quadrant of spatial probe trial was reduced in the model group (0.05), the score of neurological function was reduced on day 6, the back front distance on the left was reduced on day 14, RPM of the rota-rod were increased on day 14 and 21, the latency of navigation trial were reduced from day 23 to 25 and the movement time percentage in Q3 quadrant of spatial probe trial was increased in the treatment group (<0.01, <0.05).@*CONCLUSION@#'s three-needle acupuncture at head acupoints combined with rota-rod training improve the behavioral performance of pMCAO rats and promote the recovery of motor and cognitive functions.

Effects of low-fat diet or statin intervention at early age on brain Aβ pathology and behaviors of middle-aged Tg2576 mice / 中华神经医学杂志

Objective To investigate the effects of low-fat diet or statin intervention at early age on brain amyloid β-protein (Aβ) pathology and behaviors of middle-aged Tg2576 mice.Methods Thirty-five two-month-old Tg2576 mice were randomly divided into following 5 groups:a juvenile statin group,a juvenile low-fat diet group,a young statin group,a young low-fat group,and a blank control group (n=7);mice in the low-fat diet groups were given standard low-fat feed,and mice in the statin group were given atorvastatin at 17 mg/(kg· d) into the normal diet.The initiation times of intervention were,respectively,set to be 2-month-old in juvenile groups and 6-month-old in young groups;meanwhile,mice in the blank-control group were fed with normal diet without statin.All mice were raised to be 10-month-old and tested by Morris water maze for evaluating cognitive behaviors two weeks before execution.After peripheral blood and brains being taken,a monoclonal anti-Aβ42 antibody was employed to immunostain mice brain paraffin tissue sections for assaying tissue Aβ plaque immunoreactivity (TAPIR),and the levels of Aβ40,Aβ42,β-secretase,and γ-secretase in homogenates were detected by enzyme-linked immunosorbent assays (ELISA).Results As compared with those in the blank-control group,the average escape latencies,times of passing through hidden platforms,percentage of strong TAPIR,Aβ42 and γ-secretase level in all intervention groups showed no statistical differences (P＞0.05).As compared with those in the blank control group,Aβ42 in homogenates of young intervention groups and β-secretase level in the young statin group were significantly higher (P＜0.05).Conclusion Interventions initiated from juvenile or young,and low-fat diet intervention or statin intervention can neither improve the mice's Morris water maze testing results,nor reduce Aβs burdens in brain homogenates and Aβ40 immunopathologies in brain tissues of middle-aged mice;over early initiation of low-fat diet intervention or statin intervention might accelerate or worsen Alzheimer's disease progress.

The effects of offspring's behavior and SERT and TPH during the lactation exposure to fluoxetine / 中国神经精神疾病杂志

Objective To explore the influence of the lactation exposure to fluoxetine on offspring's behavior and serotonin transporter (SERT) and tryptophan hydroxylase (TPH). Methods Six SD pregnant rats were randomly divided into 2 groups (n=3 each group). Experimental maternal rats were intraperitoneally injected with fluoxetine at a dose of 12 mg/kg from postnatal day 5 to 21. The control group were injected with the same amount of normal saline. In infancy, the offspring's weight, hair length, eye opening and auditory development were measured. The free suspension test and bur?ied food pellets test were applied to evaluate the offspring's behaviors. After postnatal day 21, all the offspring were wean. At early childhood (P35d) and adulthood (P75d), 6 offspring rats from each group were executed to examine SERT and TPH in the prefrontal cortex by immunohistochemistry. Results The offspring's weight of experimental group was significantly lower than control group (P<0.05). The sensitivity of auditory in experimental group was significantly higher than control group (P<0.01). The time of free suspension in experimental group significantly was decreased comparing to control group (P<0.01). The SERT and TPH in prefrontal cortex was significantly lower in experimental group than those in control group either at childhood (P35d) or at adulthood (P75d) (P<0.05). Conclusion Lactation exposure to fluoxetine re?sults in offspring's abnormal development and behaviors through down-regulation of SERT and TPH in the prefrontal cor?tex.

Effects of Wenjing Tongluo Formula on GFAP Level in Perpheral Neuropathy Rats / 中国中医药信息杂志

Objective To discuss the treatment action and mechanism of Wenjing Tongluo Formula on oxaliplatin-induced perpheral neurotoxicity in rats. Methods Intraperitoneal injection was used to inject oxaliplatin 4 mg/kg to establish oxaliplatin-induced peripheral neurotoxicity rat models. Female Wistar rats were randomly divided into normal group, model group, and TCM group. TCM group was given Wenjing Tongluo Formula to soak rats’ limbs and tails. Rats in the model group were soaked with deionized water for comparison. Rats in the normal group received intraperitoneal injection with 5%glucose. Algesia hypersensitivity and anaphylaxis were detected under the mechanical stimulation and temperature. Immunohistochemical method was used to detect the expression of GFAP in L4-L6 spinal dorsal horn of rats. Explore the level of GLT-1 in L4-L6 dorsal root ganglia by RT-PCR. Results Rats in model group showed obvious behavioral changes compared with normal group (P<0.05);Rats in the TCM group improved in behavioristics compared with model group (P<0.01);number of positive cells in GFAP of rats in the model group increased compared with normal group (P<0.05);the increase in the TCM group was not obvious. Compared with normal group, astrocytes in spinal dorsal horn of model group were enlarged, protuberances increased, became coarse, and GLT-1 mRNA is decreased (P<0.05, P<0.01). Compared with model group, active cells and protuberances in the TCM group decreased (P<0.01), GLT-1 mRNA is increased (P<0.01). Conclusion Wenjing Tongluo Formula can improve behavioral changes of model rats under temperature and mechanical stimulation, probably related to harmful signal transmission induced by inhibition of astrocyte in spinal dorsal horn.

Electrophysiology of hippocampal neurons and behavior characteristics in mouse models of intracerebral hemorrhage / 中华神经医学杂志

Objective To establish mouse models of intracerebral hemorrhage using autologous arterial blood,to study the physiological property of hippocampal neurons,brain edema changes and learning ability in the mouse models after intracerebral hemorrhage.Methods Eighty male C57/BL6 mice were randomly divided into intracerebral hemorrhage group and control group (n=40); 20 μL arterial blood from the tail arteries or normal saline were injected into the caudate nucleus of intracerebral hemorrhage group and control group by stereotactic technique,respectively.One,three,five and seven d after injection,the neurological impairment was scored; the behavioral changes of the mice in the Morris water maze (navigation test and space exploration experiment) were observed; brain edema was measured by wet and dry weight method and electrophysiological differences of hippocampal neurons were recorded by whole-cell patch-clamp technique and computer software.Results As compared with those in the control group,significantly increased neurological deficit scores one,three,five and seven d after injection,statistically decreased residence time in the platform on the fifth d of training,obviously increased water content around the brain edema one,three,five and seven d after injection,and significantly decreased resting membrane potential and input resistance in the hippocampal CA1 pyramidal cells five d after injection of mice in the intracerebral hemorrhage group were noted (P＜0.05).Conclusion The hippocampus-dependent spatial leaming ability of intracerebral hemorrhage mice is decreased,and the permeability of potassium channels is enhanced.