Effect of Nao Yikang on choline acetyltransferase and caspase-3 brain expression in a rat model of Alzheimer's disease

BACKGROUND： The main components of the traditional Chinese medicine compound Nao Yikang have been shown to possibly alleviate neural damage. OBJECTIVE： To observe the effects of Nao Yikang on expression of choline acetyltransferase （CHAT） and caspase-3 in the rat brains of an experimental Alzheimer＇s disease （AD） model, and to investigate the mechanisms of potential neuroprotective effects. DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Department of Pathophysiology, Medical School of Nantong University between November 2006 and December 2007. MATERIALS： The main active components of Nao Yikang were as follows： prepared polygonum multiflorum, Rhizoma anemarrhenae, and Rhizoma acori tatarinowii. Nao Yikang granules were prepared by Nantong Hospital of Traditional Chinese Medicine. Ibotenic acid （IBO） was purchased from Sigma-Aldrich, USA, ChAT goat anti-rat antibody from Chemicon, USA, and cleaved caspase-3 rabbit anti-rat （Asp175） （5A1） antibody from Cell Signaling, USA. METHODS： A total of 60 male, Sprague Dawley rats （2 months old） were randomly assigned to 6 groups： sham-surgery, model, Nao Yikang 1.73, 3.45, 6.90 g/kg per day, and piracetam, with 10 rats in each group. Bilateral infusions of 5 pg IBO into the nucleus basalis of Meynert were performed with Hamilton syringe and stereotaxic apparatus for AD model establishment. For the sham-surgery group, rats received 1 μL saline in the identical stereotaxic position. From the second day, Nao Yikang groups were administrated 1.73, 3.45, and 6.90 g/kg per day Nao Yikang, respectively, while the piracetam group received 0.04 g/mL piracetam, the model group received 0.5% sodium carboxymethyl cellulose, and the sham-surgery group received normal saline. Rats were intragastrically administered 1 mL/100 g daily for 28 consecutive days. MAIN OUTCOME MEASURES： Following treatment of the various solutions for 28 days, Western blot was utilized to observe ChAT expression in the frontal cortex of AD rats, and immunohistochemistry was applied to quantify caspase-3-positive cells in the frontal cortex. RESULTS： ChAT protein expression significantly decreased in the model group （P 〈 0.01）, however caspase-3 expression was significantly elevated （P 〈 0.01） compared with the sham-surgery group. Compared with the model group, ChAT protein expression increased in the Nao Yikang 1.73 g/kg per day, 3.45 g/kg per day, 6.90 g/kg per day groups, and the piracetam group （P 〈 0.05 or P 〈 0.01） and the number of caspase-3-positive cells decreased in the Nao Yikang 3.45 g/kg per day and 6.90 g/kg per day groups （P 〈 0.01）. However, there was no change in the number of caspase-3-positive cells in the 3.45 g/kg per day group. CONCLUSION： The traditional Chinese medicine compound Nao Yikang increased ChAT protein expression and suppressed caspase-3 expression in the frontal cortex in a dose-dependent manner.

Estrogen intervention in microvascular morphology and choline acetyltransferase expression in rat hippocampal neurons in chronic cerebral ischemia

We observed dynamic changes in microvessels and a protective effect of estrogen on chronic cerebral ischemia ovariectomized rat models established through permanent occlusion of bilateral carotid arteries at 7, 14 and 21 days. The results revealed that estrogen improved microvasculature in the hippocampus of chronic cerebral ischemic rats, upregulated Bcl-2 protein expression, downregulated Bax protein expression, increased choline acetyltransferase expression in hippocampal cholinergic neurons, and suppressed hippocampal neuronal apoptosis. These findings indicate that estrogen can protect hippocampal neurons in rats with chronic cerebral ischemia.

Effects of gentamicin on choline acetyltransferase expression in paraolivary nucleus neurons of guinea pigs

BACKGROUND： It is generally accepted that gentamicin can damage the cochlear nerve and acoustic nerve. In recent years, scholars have focused on neuronal changes and neurochemical information in the brainstem primary auditory center. OBJECTIVE： To explore morphological changes of choline acetyltransferase （ChAT）-positive neurons in the paraolivary nucleus （PON） of guinea pigs, and the effect on hearing following gentamicin injection. DESIGN, TIME AND SETTING： Randomized grouping and morphological observational study was performed at Animal Experimental Center of General Hospital of Shenyang Military Area Command of Chinese PLA from January to August 2007. MATERIALS： A total of 48 healthy guinea pigs were randomly divided into model （n = 40） and control （n = 8） groups. The model group was divided into five subgroups at five time points of 1 and 3 days, 1, 2, and 3 weeks. METHODS： Guinea pigs in the model group were intraperitoneally injected with gentamicin, and those in the control group were intraperitoneally injected with the same volume of saline. MAIN OUTCOME MEASURES： Auditory brainstem-evoked potential was used to record auditory threshold; distribution and morphological changes of ChAT-positive neurons in the PON were observed with immunohistochemistry; section area and gray value of ChAT-positive neurons were measured with Quantimet 570 image-analyzing system. RESULTS： ChAT-positive neurons were diffusedly distributed in the PON. The majority was composed of large, round cells, with positive neurites that could be clearly observed. Following gentamicin injection, the positive neurons displayed an irregular outline, and their neurites began to shorten and disappear. The gray value increased with prolonged gentamicin administration （P 〈 0.05）. In addition, the somatic cross-sectional area was enlarged in the model group at 1 and 3 days after injection （P 〈 0.05）, whereas cell number significantly decreased at ;three weeks after injection （P 〈 0.05）. Starting at 3-4 days, behavioral features and auditory degrees became gradually aggravated with prolonged gentamicin administration （P 〈 0.05）. CONCLUSION： Gentamicin damaged ChAT-positive neurons in the PON, and long-term gentamicin treatment aggravated hearing impairment.

Effect of bilobalide B on cholinergic hippocampal neurons exposed to cholesterol and apolipoprotein E4

BACKGROUND： Extracts of ginkgo biloba leaves have been reported to improve nerve function and activity in Alzheimer＇s disease, which is associated with reduced secretion of cholinergic neurotransmitter in hippocampal neurons. OBJECTIVE： To validate the protective effect of bilobalide B against in vitro injury of cholinergic neurons of the hippocampus induced by combined cholesterol and apoE4 DESIGN, TIME AND SETTING： This randomized, controlled animal experiment was performed in the Pathology Laboratory, Tianjin University of Traditional Chinese Medicine from July 2003 to July 2006. MATERIALS： Neonatal Wistar rats, 1-day-old, both male and female, and mean body mass of 5 g were selected for this study. Cholesterol and apolipoprotein E4 （apoE4） were purchased from Sigma Company （USA）, bilobalide B was purchased from Tianjin Zhongyi Pharmaceutical Factory, batch number 20050312. METHODS： Hippocampal neurons were divided into three groups： a normal control group （routinely added media）, a model group （exposed to media containing 40 mg/L cholesterol and 30 mg/L apoE4 for 24 hours） and a bilobalide B group （exposed to media containing 160 mg/L bilobalide B for 16 hours, and then with addition of 40 mg/L cholesterol and 30 mg/L apoE4 for an additional 24 hours）. MAIN OUTCOME MEASURES： Levels of acetylcholine （ACh） and activity of acetylcholinesterase （ACHE） and choline acetyltransferase （CHAT） in hippocampal neurons were determined by microdosage hydroxylamine colorimetry, hydroxylamine colorimetry and radiological chemistry, respectively. RESULTS： The ACh level was significantly lower in the model group than that in the normal control group （P 〈 0.01）, while it was markedly higher in the bilobalide B group than in the model group （P 〈 0.05）. Activity of AChE was significantly decreased in the model group compared with the normal control group （P 〈 0.05）. However, there was no significant difference between the model group and the bilobalide B group （P 〉 0.05）. Activity of ChAT was significantly lower in the model group than in the normal control group （P 〈 0.01）, while the activity was significantly higher in the bilobalide B group than in the model group （P 〈 0.05）. CONCLUSION： Bilobalide B can enhance the ACh level of hippocampal neurons damaged by combined cholesterol and apoE4, by promoting the synthesis, but not the degradation, of ACh.

Pathway for interferon-gamma to promote the differentiation of cholinergic neurons in rat embryonic basal forebrain/septal nuclei

BACKGROUND： The supernatant of interferon-gamma （IFNγ） co-cultured with neonatal rat cortical glia can promote the cells in embryonic basal forebrain/septal nuclei to differentiate into cholinergic neurons, but the mechanism is still unclear. OBJECTIVE： To analyze the pathways for IFNγ to promote the differentiation of primarily cultured cholinergic neurons in rat embryonic basal forebrain/septal nuclei through culture in different conditioned medium. DESIGN： A controlled experiment taking cells as the observational target. SETTINGS： Department of Biochemistry and Molecular Biology, Youjiang Medical College for Nationalities; Department of Cell Biology, Beijing University Health Science Center. MATERIALS： Sixty-four pregnant Wistar rats for 16 days （250-350 g） and 84 Wistar rats （either male or female, 5-7 g） of 0-1 day after birth were provided by the experimental animal department of Beijing University Health Science Center. Rat IFNγ were provided by Gibco Company; Glial fibrillary acidic protein by Huamei Company. METHODS： The experiments were carried out in the Department of Cell Biology, Beijing University Health Science Center and Daheng Image Company of Chinese Academy of Science from July 1995 to December 2002. ① Interventions： The nerve cells in the basal forebrain/septal nuclei of the pregnant Wistar rats for 16 days were primarily cultured, and then divided into four groups： Blank control group （not any supernatant and medium was added）; Control group （added by mixed glial cell or astrocyte conditioned medium）; IFNγ group （added by mixed glial cell or astrocyte conditioned medium＋IFNγ）. Antibody group （added by mixed glial cell or astrocyte conditioned medium＋IFNγ＋Ab-IFNγ）. Mixed glial cell or astrocyte conditioned medium was prepared using cerebral cortex of Wistar rats of 0-1 day after birth. ② Evaluation： The immunohistochemical method was used to perform the choline acetyltransferase （ChAT） staining of cholinergic neurons. The ChAT positive cells were counted. MAIN OUTCOME MEASURES： Comparison of ChAT positive cells in rat basal forebrain and septal nuclei in different conditioned medium. RESULTS： ① ChAT positive cells in mixed glial cell conditioned medium： The ChAT positive cells in the IFNγ group and antibody group were significantly more than those in the control group （P 〈 0.01）. ② ChAT positive cells in astrocyte conditioned medium： The ChAT positive cells in the IFNγ group were significantly more than those in the control group, but there was no significant difference between the antibody group and control group （P 〉 0.05）. CONCLUSION： IFNγ cannot directly promote the differentiation of cholinergic neurons, but plays a role through activating glial cells （except astrocytes） to produce IFNγ like molecules.

Chronic Kidney Disease Induces Cognitive Impairment in the Early Stage

Objective Previous research indicates a link between cognitive impairment and chronic kidney disease(CKD),but the underlying factors are not fully understood.This study aimed to investigate the progression of CKD-induced cognitive impairment and the involvement of cognition-related proteins by developing early-and late-stage CKD models in Sprague-Dawley rats.Methods The Morris water maze test and the step-down passive avoidance task were performed to evaluate the cognitive abilities of the rats at 24 weeks after surgery.Histopathologic examinations were conducted to examine renal and hippocampal damage.Real-time PCR,Western blotting analysis,and immunohistochemical staining were carried out to determine the hippocampal expression of brain-derived neurotrophic factor(BDNF),choline acetyltransferase(ChAT),and synaptophysin(SYP).Results Compared with the control rats,the rats with early-stage CKD exhibited mild renal damage,while those with late-stage CKD showed significantly increased serum creatinine levels as well as apparent renal and brain damage.The rats with early-stage CKD also demonstrated significantly impaired learning abilities and memory compared with the control rats,with further deterioration observed in the rats with late-stage CKD.Additionally,we observed a significant downregulation of cognition-related proteins in the hippocampus of rats with early-stage CKD,which was further exacerbated with declining renal function as well as worsening brain and renal damage in rats with late-stage CKD.Conclusion These results suggest the importance of early screening to identify CKD-induced cognitive dysfunction promptly.In addition,the downregulation of cognition-related proteins may play a role in the progression of cognitive dysfunction.

Therapeutic potential of Gastrodia elata Blume for the treatment of Alzheimer's disease

Several studies have demonstrated that the Chinese herb Gastrodia elata Blume can protect against amyloid beta-peptide （Ap）-induced cell death. To investigate the possible therapeutic effects of Gastrodia elata Blume on Alzheimer＇s disease, we established a rat model of AIzheimer＇s disease by injecting A325-35 into bilateral hippocampi. These rats were intragastrically administered 500 or 1 000 mg/kg Gastrodia elata Blume per day for 52 consecutive days. Morris water maze tests showed that Gastrodia elata Blume treatment significantly improved the spatial memory of Alzheimer＇s disease rats. Congo red staining revealed that Gastrodia elata Blume significantly reduced the number of amyloid deposits in the hippocampus of these rats. Western blot analysis showed that choline acetyltransferase expression in the medial septum and hippocampus was significantly increased by the treatment of Gastrodia elata Blume, while EIIman method showed significant decrease in the activity of acetylcholinesterase in all three regions （prefrontal cortex, medial septum and hippocampus）. These findings suggest that long-term administration of Gastrodia elata Blume has therapeutic potential for Alzheimer＇s disease.

Early electrical field stimulation prevents the loss of spinal cord anterior horn motoneurons and muscle atrophy following spinal cord injury

Our previous study revealed that early application of electrical field stimulation（EFS） with the anode at the lesion and the cathode distal to the lesion reduced injury potential, inhibited secondary injury and was neuroprotective in the dorsal corticospinal tract after spinal cord injury（SCI）. The objective of this study was to further evaluate the effect of EFS on protection of anterior horn motoneurons and their target musculature after SCI and its mechanism. Rats were randomized into three equal groups. The EFS group received EFS for 30 minutes immediately after injury at T_（10）. SCI group rats were only subjected to SCI and sham group rats were only subjected to laminectomy. Luxol fast blue staining demonstrated that spinal cord tissue in the injury center was better protected; cross-sectional area and perimeter of injured tissue were significantly smaller in the EFS group than in the SCI group. Immunofluorescence and transmission electron microscopy showed that the number of spinal cord anterior horn motoneurons was greater and the number of abnormal neurons reduced in the EFS group compared with the SCI group. Wet weight and cross-sectional area of vastus lateralis muscles were smaller in the SCI group to in the sham group. However, EFS improved muscle atrophy and behavioral examination showed that EFS significantly increased the angle in the inclined plane test and Tarlov＇s motor grading score. The above results confirm that early EFS can effectively impede spinal cord anterior horn motoneuron loss, promote motor function recovery and reduce muscle atrophy in rats after SCI.

Effect of intravenous transplantation of bone marrow mesenchymal stem cells on neurotransmitters and synapsins in rats with spinal cord injury

Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro by Percoll density gradient centrifugation combined with the cell adherence method. Passages 3 5 bone marrow mesenchymal stem cells were transplanted into rats with traumatic spinal cord injury via the caudal vein. Basso-Beattie-Bresnahan scores indicate that neurological function of experimental rats was significantly improved over transplantation time （1-5 weeks）. Expressions of choline acetyltransferase, glutamic acid decarboxytase and synapsins in the damaged spinal cord of rats was significantly increased after transplantation, determined by immunofluorescence staining and laser confocal scanning microscopy. Bone marrow mesenchymal stem cells that had migrated into the damaged area of rats in the experimental group began to express choline acetyltransferase, glutamic acid decarboxylase and synapsins, 3 weeks after transplantation. The Basso-Beattie- Bresnahan scores positively correlated with expression of choline acetyltransferase and synapsins. Experimental findings indicate that intravenously transplanted bone marrow mesenchymal stem cells traverse into the damaged spinal cord of rats, promote expression of choline acetyltransferase, glutamic acid decarboxylase and synapsins, and improve nerve function in rats with spinal cord injury.

Effects of Estrogen on ER, NGF, and ChAT Expression in Cerebellum of Aging Female Sprague-Dawley Rat

This article discusses the effects of estrogen on the expression of estrogen receptor （ER）, nerve growth factor （NGF）, and choline acetyltransferase （CHAT） in the cerebellum of rats. The model of aging female rat was established to study the expression and distribution of ER, NGF, and ChAT in the cerebellum following 17β-estradiol treatment using the technique of immunohistochemical ultrasensitive SP in sprague-dawley rat. The immunoreactive productions were distributed in stratum Purkinje cell, nucleus dentatus, nucleus interpositus, and nucleus fastigii of cerebellum, and the ER positive production was mainly located in the plasma, cytoplasmic membrane, and neurite, and also existed in nucleus. The general tendency of the expression of ER, NGF, and ChAT positive production in the cerebellum cortex and nuclei of aging rat significantly decreases, while the intensity and quantity of the immunoreactive production ascends predominantly after 17β-estradiol treatment. Simultaneously, the positive neurite of Purkinje cell shows a similar tendency. The above- mentioned results suggest that the estrogen upregulates the expression of NGF and CHAT, and plays a vital role in sustaining and protecting the structure and function of cerebellum neurons. Furthermore, the similarity of their changing tendency implies that they were correlated and cooperated during the course in effect of estrogen on cerebellum. It also showed that the action of estrogen in cerebellum could be via genomic and nongenomic mechanism.

Preconditioning crush increases the survival rate of motor neurons after spinal root avulsion

In a previous study, heat shock protein 27 was persistently upregulated in ventral motor neurons following nerve root avulsion or crush. Here, we examined whether the upregulation of heat shock protein 27 would increase the survival rate of motor neurons. Rats were divided into two groups： an avulsion-only group （avtflsion of the L4 lumbar nerve root only） and a crush-avulsion group （the L4 lumbar nerve root was crushed 1 week prior to the avulsion）. Immunofluores- cent staining revealed that the survival rate of motor neurons was significantly greater in the crush-avulsion group than in the avulsion-only group, and this difference remained for at least 5 weeks after avulsion. The higher neuronal survival rate may be explained by the upregulation of heat shock protein 27 expression in motor neurons in the crush-avulsion group. Further- more, preconditioning crush greatly attenuated the expression of nitric oxide synthase in the motor neurons. Our findings indicate that the neuroprotective action of preconditioning crush is mediated through the upregulation of heat shock protein 27 expression and the attenuation of neuronal nitric oxide synthase upregulation following avulsion.

Morphologic Relationship between the Pontine Micturition Center and the Sympathetic Center in the Spinal Cord of the Rat

To study whether the sympathetic nerves coordinate with the parasympathetic nerves during micturition in the rat. We used antegrade neural tracing with biotinylated dextran amine (BDA) injected into the pontine micturition center (PMC) to label the terminals in the L6-S1 cord. Preganglionic parasympathetic neurons (PPNs) in the L6-S1 segment were labelled by retrograde transport of Fluorogold (FG) from the major pelvic ganglion (MPG).We detected retrograde neurons in L6-S1 using retrograde transport of horseradish peroxidase (HRP) from the intermediolateral cell column (IML) of the L1-L2 segment where sympathetic preganglionic neurons (SPNs) are located. Immunohistochemical methods showed that PPNs were identified to be choline acetyltransferase-immunoreactive (ChAT-IR). HRP-labelled neurons were not ChAT-IR and located dorsal to PPNs. BDA-labelled terminals were located mainly in the bilateral IML of L6-S1, some of which had synaptic contact with the HRP-labelled neurons. In addition, there were some wheat germ agglutinin-horseradish peroxidase (WGA-HRP) labelled terminals in the ipsilateral IML of the L1-L2 segment after WGA-HRP was microinjected into SPN. We conclude that PMC may control the preganglionic neurons of sympathetic nerves through the interneurons located dorsal to PPNs.

Vagal-mAChR4 signaling promotes Friend virus complex(FV)-induced acute erythroleukemia

Erythroleukemia belongs to acute myeloid leukemia(AML)type 6(M6),and treatment remains difficult due to the poor prognosis of the disease.Friend virus(FV)is a complex of two viruses:Friend murine leukemia virus(F-MuLV)strain along with a defective spleen focus-forming virus(SFFV),which can induce acute eryth-roleukemia in mice.We have previously reported that activation of vagalα7 nicotinic acetylcholine receptor(nAChR)signaling promotes HIV-1 transcription.Whether vagal muscarinic signaling mediates FV-induced erythroleukemia and the underlying mechanisms remain unclear.In this study,sham and vagotomized mice were intraperitoneally injected with FV.FV infection caused anemia in sham mice,and vagotomy reversed this change.FV infection increased erythroblasts ProE,EryA,and EryB cells in the spleen,and these changes were blocked by vagotomy.In bone marrow,FV infection reduced EryC cells in sham mice,an effect that was coun-teracted by vagotomy.FV infection increased choline acetyltransferase(ChAT)expression in splenic CD4^(+)and CD8þT cells,and this change was reversed by vagotomy.Furthermore,the increase of EryA and EryB cells in spleen of FV-infected wild-type mice was reversed after deletion of ChAT in CD4^(+)T cells.In bone marrow,FV infection reduced EryB and EryC cells in sham mice,whereas lack of ChAT in CD4^(+)T cells did not affect this change.Activation of muscarinic acetylcholine receptor 4(mAChR4)by clozapine N-oxide(CNO)significantly increased EryB in the spleen but decreased the EryC cell population in the bone marrow of FV-infected mice.Thus,vagal-mAChR4 signaling in the spleen and bone marrow synergistically promotes the pathogenesis of acute erythroleukemia.We uncover an unrecognized mechanism of neuromodulation in erythroleukemia.

dl-3-n-butylphthalide reduces brain damage in mice with closed head injury

To investigate the protective effect of dl 3 n butylphthalide (NBP) as an anti cerebral ischemic drug on brain damage 24?h after closed head injury in mice Methods Closed head injury was induced by dropping a 50 g weight from a height of 18?cm on a metal impounder resting on the parietal bone in mice Results The neurotraumatic model induced impair^ment of memory function, significant cerebral edema, and disruption of the blood brain barrier dl 3 n butylphthalide (50?mg·kg 1 ) given intraperitoneally 5 minutes and 60 minutes after the onset of closed head injury was found to attenuate the impairment of memory function ( P <0 05), alleviate brain edema in the injured cerebral cortex ( P <0 05), and reduce extravasation of plasma protein bound to Evans blue dye by 63 5% ( P <0 01) NBP was also shown to increase the activity of choline acetyltransferase in the injured cortex to 0 83±0 21?ng·min 1 ·mg 1 ( P <0 01, compared with 0 48±0 14?ng·min 1 ·mg 1 of vehicle group) Conclusion NBP provides therapeutic response in experimental closed head injury