Effects of l-3-n-Butylphthalide on Cognitive Dysfunction and NR2B Expression in Hippocampus of Streptozotocin (STZ)-Induced Diabetic Rats

The effect of butylphthalide on aminoacid content in the brain of epileptic mice

BACKGROUND

The aim of this study is to observe the effect of butylphthalide (NBP) on the amino acid content in the brain of epileptic mice.

METHODS

NBP was injected intraperitoneally into the mice, and acute epileptic mice models were made after 30 minutes. The change of the four amino (aspartic acid, gamma-aminobutyric acid, glutamate, glycine) content in the brain of the epileptic mice was investigated.

RESULTS

The contents of Glu and Glu/GABA (control group: 38.78, NBP high-dose group: 5.52) in the NBP high-dose group were lower compared with the control group. The difference was statistically significant.

CONCLUSIONS

NBP could regulate the balance of excitement and inhibition systems by reducing the contents of Glu and Glu/GABA, which might relieve seizures.

Advances of neurovascular protective potential of 3-N-butylphthalide and its derivatives in diabetic related diseases

3-N-butylphthalide (NBP) is a component isolated from seeds of Chinese celery, and it was firstly approved for the treatment of ischemic stroke. With the gradual in-depth understanding of its pharmacological action, it was found that it may have potential effects on treating diabetes and its complications. This review aims to illustrate the researches on the properties of NBP and its therapeutic efficacy in diabetic related diseases. This review will discuss the results of experiments in vitro and in vivo to make progress in understanding the beneficial effects of NBP and its derivatives on diabetic complications including diabetic vascular diseases, diabetic peripheral neuropathy, diabetic brain related diseases and diabetic cataract. We will also demonstrate NBP's numerous molecular targets and interactions with multiple cellular signaling pathways such as oxidative stress, inflammatory responses, apoptosis and autophagy. NBP is proved to be a potential therapeutic approach for treating diabetic complications.

Clinical Application Potential of Small Molecules that Induce Brown Adipose Tissue Thermogenesis by Improving Fat Metabolism

Mammalian fat comprises white and brown adipose tissue (WAT and BAT, respectively). WAT stores energy, whereas BAT is used for thermogenesis. In recent years, the incidence of obesity and its associated disorders have increased tremendously. Considering the thermogenic capacity and decreased levels of BAT with increasing age, BAT can be used as a suitable therapeutic target for the treatment of obesity and diabetes. In several studies, using positron emission tomography and computed tomography images, adult humans have been shown to have functional BAT in interscapular fat. Results of these basic research studies on BAT have shed light on the new components of transcriptional regulation and the role of hormones in stimulating BAT growth and differentiation. In this review article, we have summarized the thermogenic regulators identified in the past decades by focusing on peroxisome proliferator-activated receptor gamma/uncoupling protein 1 activators, branched-chain amino acids, fatty acids (lipokine), and adenosine monophosphate-activated protein kinase mediators. We have also presented the progress of a few ongoing clinical trials aimed at the treatment of obesity and its associated metabolic disorders. The main purpose of this review was to provide a comprehensive introduction to the latest knowledge of the representative thermogenic regulators for the treatment of obesity. The fat combustion capacity of BAT may have great potential and can be considered as a suitable target for the therapeutic application of drugs from bench-to-bed treatment of obesity and the associated diseases.

From Seeds of Apium graveolens Linn. to a Cerebral Ischemia Medicine: The Long Journey of 3-n-Butylphthalide

3-n-Butylphthalide (NBP) as well as its derivatives and analogues (NBPs), in racemic or enantiomerically pure forms, possess potent and diverse pharmacological properties and have shown a great potential therapeutic interest for many human conditions, especially for cerebral ischemia. This Perspective outlines the synthesis and therapeutic applications of NBPs.

Correlation Between Diabetic Cognitive Impairment and Diabetic Retinopathy in Patients With T2DM by 1H-MRS

Objective: To explore the correlation between diabetic cognitive impairment (DCI) and diabetic retinopathy (DR) through examining the cognitive function and the metabolism of the cerebrum in Type 2 diabetes mellitus (T2DM) by ¹H-MRS.

Methods: Fifty-three patients with T2DM were enrolled for this study. According to the fundus examination, the patients were divided into the DR group (n = 26) and the T2DM without DR group (T2DM group, n = 27). Thirty healthy adults were selected as a control group (HC group, n = 30). Cognitive function was measured by Montreal Cognitive Assessment (MoCA). The peak areas of N-acetylaspartate (NAA), Cho-line (Cho), Creatine (Cr), and Myo-inositol (mI) as well as their ratios were detected by proton magnetic resonance spectroscopy (¹H-MRS). The difference analysis between the three groups was performed by one-way ANOVA. When p < 0.05, LSD-t was applied. A partial correlation analysis (with age as a covariate) was used to analyze the correlation between metabolites in the DR group and MoCA scores. Among all T2DM patients, Chi-square test age, gender, education level, BMI, SBP, DBP, FPG, HbA1c, TC, TG, HDL-C, LDL-C, DR, and DCI correlation were measured. Differences were statistically significant while P < 0.05.

Results: 1. The scores of MoCA in the DR group or in the T2DM group were significantly less than those in the HC group (F = 3.54, P < 0.05), and the scores of MoCA in the DR group were significantly less than those in the other groups (F = 3.61, P < 0.05). 2. There were significant differences for NAA in the bilateral hippocampus in DR patients, T2DM patients, and healthy controls (P < 0.05). 3. The NAA/Cr was significantly positively correlated with the score of MoCA in DR patients' left hippocampus (r = 0.781, P < 0.01). 4. Chi-square analysis found that there was a correlation between DR and DCI (x² = 4.6, df = 1, p = 0.032, plt: 0.05). There was no correlation between other influencing factors and DCI (P > 0.05).

Conclusion: DCI is closely correlated with the DR in patients with T2DM. Hippocampal brain metabolism may have some changes in two sides of NAA in patients with DR, ¹H-MRS may provide effective imaging strategies and methods for the early diagnosis of brain damage and quantitative assessment cognitive function in T2DM.

L-3-n-butylphthalide attenuates cognitive deficits in db/db diabetic mice

Numerous epidemiological studies have shown that diabetes mellitus (DM) is associated with dementia and cognition decline. However, there is currently no effective treatment for diabetes-induced cognitive dysfunction. The neuroprotective effect of L-3-n-butylphthalide (L-NBP) has been demonstrated in vascular dementia animal models. The purpose of this study was to determine whether L-NBP can ameliorate cognitive deficits in db/db mice, a model of obesity and type 2 diabetes. The mice were administered with vehicle or L-NBP (120 mg/kg) by gavage daily for 6 weeks. Then, Morris water maze tasks were performed, and hippocampal LTP was recorded in vivo. Next, the synaptic structure of the CA1 hippocampus region was investigated via electron microscopy. Finally, the expression levels of MDA, SOD, 8-OHdG, and NADPH oxidase subunits gp91 and p67, as well as the expression of NF-κB p65, TNF-α, IL-1β and caspase-3 were measured by Western blot, RT-PCR and ELISA. Treatment with L-NBP significantly attenuated the learning and memory deficits in db/db mice. Concomitantly, L-NBP also increased hippocampus synaptic plasticity, characterized by an enhanced in vivo LTP, and suppressed oxidative stress, as indicated by increased SOD activity and decreased MDA, 8-OHdG, and NADPH oxidase subunits p67 and gp91. L-NBP also significantly decreased NF-κB p65, TNF-α, IL-1βand caspase-3 levels in the hippocampus. L-NBP significantly ameliorated cognitive decline in type 2 diabetic mice, and this effect was accompanied by an improvement in hippocampal plasticity and an amelioration of oxidative stress, inflammation and apoptosis cascades. Thus, L-NBP may be a promising therapeutic agent against DM-mediated cognitive dysfunction.

3-N-Butylphthalide mitigates high glucose-induced injury to Schwann cells: association with nitrosation and apoptosis

A high glucose state readily causes peripheral axon atrophy, demyelination, loss of nerve fiber function, and delayed regeneration. However, few studies have examined whether nitration is also critical for diabetic peripheral neuropathy. Therefore, this study investigated the effects of high glucose on proliferation, apoptosis, and 3-nitrotyrosine levels of Schwann cells treated with butylphthalide. In addition, we explored potential protective mechanisms of butylphthalide on peripheral nerves. Schwann cells were cultured in vitro with high glucose then stimulated with the peroxynitrite anion inhibitors uric acid and 3-n-butylphthalide for 48 hours. Cell Counting Kit-8 and flow cytometry were used to investigate the effects of uric acid and 3-n-butylphthalide on proliferation and apoptosis of Schwann cells exposed to a high glucose environment. Effects of uric acid and 3-n-butylphthalide on levels of 3-nitrotyrosine in Schwann cells were detected by enzyme-linked immunosorbent assay. The results indicated that Schwann cells cultured in high glucose showed decreased proliferation, but increased apoptosis and intracellular 3-nitrotyrosine levels. However, intervention with uric acid or 3-n-butylphthalide could increase proliferation of Schwann cells cultured in high glucose, and inhibited apoptosis and intracellular 3-nitrotyrosine levels. According to our data, 3-n-butylphthalide may inhibit cell nitrification and apoptosis, and promote cell proliferation, thereby reducing damage to Schwann cells caused by high glucose.

Endosulfan and Cypermethrin Pesticide Mixture Induces Synergistic or Antagonistic Effects on Developmental Exposed Rats Depending on the Analyzed Behavioral or Neurochemical End Points

Exposure to pesticides has been associated with neurodevelopmental toxicity. Usually people are exposed to mixtures of pesticides. However, most studies analyze the effects of individual pesticides. Developmental exposure to mixtures of pesticides may result in additive effects or in antagonistic or synergistic effects. The aim of this work was to compare the effects of developmental exposure of rats to cypermethrin or endosulfan with the effects of its mixture on cognitive and motor function and on some underlying mechanisms. Exposure to individual pesticides or the mixture was from gestational day 7 to postnatal day 21. We analyzed the effects, in males and females, on spatial learning and memory, associative learning, anxiety, motor coordination, and spontaneous motor activity. We also analyzed neuroinflammation and NMDA receptor subunits in hippocampus and extracellular GABA in cerebellum. Exposure to the mixture, but not to individual pesticides, impaired spatial memory in males, associative learning in females, and increased motor activity in males and females. This indicates a synergistic effect of cypermethrin and endolsufan exposure on these end points. In contrast, motor coordination was impaired by individual exposure to endosulfan or cypermethrin, associated with increased extracellular GABA in cerebellum, but these effects were prevented in rats exposed to the mixture, indicating an antagonistic effect of cypermethrin and endolsufan exposure on these end points. The results show different interaction modes (synergism or antagonism) of the pesticides, depending on the end point analyzed and the sex of the rats.

Endoplasmic reticulum stress-induced neuronal inflammatory response and apoptosis likely plays a key role in the development of diabetic encephalopathy

We assumed that diabetic encephalopathy (DEP) may be induced by endoplasmic reticulum (ER)-mediated inflammation and apoptosis in central nervous system. To test this notion, here we investigated the neuronal ER stress and associated inflammation and apoptosis in a type 2 diabetes model induced with high-fat diet/streptozotocin in Sprague-Dawley rats. Elevated expressions of ER stress markers, including glucose-regulated protein 78 (GRP78), activating transcription factor-6 (ATF-6), X-box binding protein-1 (XBP-1), and C/EBP homologous protein, and phosphor-Jun N-terminal kinase (p-JNK) were evident in the hippocampus CA1 of diabetic rats. These changes were also accompanied with the activation of NF-κB and the increased levels of inflammatory cytokines, tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6). Mechanistic study with in vitro cultured hippocampus neurons exposed to high glucose (HG), which induced a diabetes-like effects, shown by increased ER stress, JNK and NF-κB activation, and inflammatory response. Inhibition of ER stress by 4-phenylbutyrate (4-PBA) or blockade of JNK activity by specific inhibitor or transfection of DN-JNK attenuated HG-induced inflammation and associated apoptosis. To validate the in vitro finding, in vivo application of 4-PBA resulted in a significant reduction of diabetes-induced neuronal ER stress, inflammation and cell death, leading to the prevention of DEP. These results suggest that diabetes-induced neuronal ER stress plays the critical role for diabetes-induced neuronal inflammation and cell death, leading to the development of DEP.

Liraglutide ameliorates cognitive decline by promoting autophagy via the AMP-activated protein kinase/mammalian target of rapamycin pathway in a streptozotocin-induced mouse model of diabetes

Diabetic cognitive dysfunction has gained widespread attention for its deleterious impact on individuals with diabetes. However, few clinical interventions are available to prevent the disorder. The glucagon-like peptide-1 analog liraglutide exerts neuroprotective effects in several models of neurodegenerative diseases. We investigated the effect of liraglutide pretreatment on diabetes-induced cognitive decline and explored the underlying mechanisms in vivo and in vitro. Liraglutide pretreatment prevented diabetes-induced cognitive impairment as assessed by the Morris Water Maze test, and alleviated neuronal injuries and ultrastructural damage to synapses in the hippocampal CA1 region. Furthermore, liraglutide promoted autophagy as indicated by enhanced expression of the autophagy markers Microtubule-associated protein 1 light chain 3 (LC3)-II and Beclin 1, decreased expression of p62, and increased formation of autophagic vacuoles and LC3-II aggregates. In vitro, liraglutide treatment elevated phosphorylated (p)-AMP-activated protein kinase (AMPK) levels and reduced p-mammalian target of rapamycin (p-mTOR) expression. Additionally, the AMPK inhibitor Compound C exhibited an inhibitory effect on liraglutide-induced increased LC3-II expression and p62 degradation. Liraglutide exhibits neuroprotective effects against diabetes-induced hippocampal neuronal injuries and cognitive impairment by promoting autophagy via the AMPK/mTOR pathway.

Dl-3n-butylphthalide reduces epileptiform activity through GluA2-lacking calcium-permeable AMPARs in epilepsy models

Epilepsy is the most prevalent chronic neurological disorder, and its pathological mechanism indicates that an imbalance between excitatory and inhibitory neurotransmission leads to neuronal hyperexcitability. Previous studies have suggested that dl-3n-butylphthalide (NBP) regulates the excitatory neurotransmitter glutamate in the brains of epileptic mice, however, the mechanisms are unknown. We investigated behavioral and electrophysiological factors in rats using NBP. In an in vivo pentylenetetrazole (PTZ)-induced epileptic seizure animal model, NBP decreased the generalized tonic-clonic seizure (GTCS) severity. In an acute hippocampal slice 4-aminopyridine (4-AP) epilepsy model in vitro, NBP decreased the epileptiform activity and miniature excitatory postsynaptic current (mEPSC) amplitude; there was no change in the miniature inhibitory postsynaptic current (mIPSC) amplitude or frequency. This effect suggested changes in excitatory synaptic transmission, which was altered through postsynaptic GluA2-lacking calcium-permeable AMPA receptors (CP-AMPARs). These findings showed that NBP suppressed epileptiform activity in these epilepsy models and provided the first detailed electrophysiological analysis of the impact of NBP in epilepsy models, which may be employed in future experimental or clinical therapies for patients with epilepsy.

Improvement of spatial learning and memory, cortical gyrification patterns and brain oxidative stress markers in diabetic rats treated with Ficus deltoidea leaf extract and vitexin

Despite the fact that Ficus deltoidea and vitexin played important roles in controlling hyperglycemia, an effective mitigation strategy dealing with cognitive deficit observed in diabetes, little is known about its neuroprotective effects. The study is aimed to determine changes in behavioral, gyrification patterns and brain oxidative stress markers in streptozotocin (STZ)-induced diabetic rats following F. deltoidea and vitexin treatments. Diabetic rats were treated orally with metformin, methanolic extract of F. deltoidea leaves and vitexin for eight weeks. Morris water maze (MWM) test was performed to evaluate learning and memory functions. The patterns of cortical gyrification were subsequently visualized using micro-computed tomography (micro-CT). Quantification of brain oxidative stress biomarkers, insulin, amylin as well as serum testosterone were measured using a spectrophotometer. The brain fatty acid composition was determined using gas chromatography (GC). Biochemical variation in brain was estimated using Fourier transform infrared (FT-IR) spectroscopy. Results showed that oral administration of F. deltoidea extract and vitexin to diabetic rats attenuated learning and memory impairment, along with several clusters of improved gyrification. Both treatments also caused a significant increase in the superoxide dismutase (SOD) and glutathione peroxidase (GPx) values, as well as a significant reduction of TBARS. Strikingly, improvement of cortical gyrification, spatial learning and memory are supported by serum testosterone levels, fatty acid composition of brain and FT-IR spectra.

N-Butylphthalide Improves Cognitive Function in Rats after Carbon Monoxide Poisoning

Cognitive impairment is the most common neurologic sequelae after carbon monoxide (CO) poisoning, and the previous investigations have demonstrated that N-Butylphthalide (NBP) could exert a broad spectrum of neuroprotective properties. The current study aimed to investigate the effect of NBP on cognitive dysfunction in rats after acute severe CO poisoning. Rats were randomly divided into a normal control group, a CO poisoning group and a CO+NBP group. The animal model of CO poisoning was established by exposure to CO in a chamber, and then all rats received hyperbaric oxygen therapy once daily, while rats in CO+NBP group were administered orally NBP (6 mg/ 100g) by gavage twice a day additionally. The results indicated that CO poisoning could induce cognitive impairment. The ultrastructure of hippocampus was seriously damaged under transmission electron microscopy, and the expressions of calpain 1 and CaMK II proteins were significantly elevated after CO exposure according to the analysis of immunofluorescence staining and western blot. NBP treatment could evidently improve cognitive function, and maintain ultrastructure integrity of hippocampus. The expression levels of both calpain 1 and CaMK II proteins in CO+NBP group were considerably lower than that of CO poisoning group (P < 0.05). Taken together, this study highlights the molecular mechanism of cognitive dysfunction in rats after CO exposure via the upregulation of both calpain 1 and CaMK II proteins. The administration of NBP could balance the expressions of calpain 1 and CaMK II proteins and improve cognitive function through maintaining ultrastructural integrity of hippocampus, and thus may play a neuroprotective role in brain tissue in rats with CO poisoning.

A Review of Recent Advances in Neuroprotective Potential of 3-N-Butylphthalide and Its Derivatives

The research of alternative treatment for ischemic stroke and degenerative diseases has always been a priority in neurology. 3-N-Butylphthalide (NBP), a family of compounds initially isolated from the seeds of Apium graveolens Linn., has shown significant neuroprotective effects. Previous extensive studies have demonstrated that NBP promotes a better poststroke outcome and exerts a multitargeted action on several mechanisms, from oxidative stress to mitochondrial dysfunction to apoptosis to inflammation. Additionally, recent findings on several neurological disorders have shown that NBP's beneficial effects extend beyond the management of stroke. However, despite the increasing number of studies toward a better understanding and the rapid advances made in therapeutic options, to date, dl-3-N-butylphthalide, a synthetic variation of l-3-N-butylphthalide, remains the only clinically approved anti-ischemic agent in China, stressing the difficulties for a viable and effective transition from experimental to clinical practice. Events indicate that NBP, due to its multitargeted effect and the adaptability of its basic structure, can be an important game changer and a precursor to a whole new therapeutic approach to several neurological conditions. The present review discusses recent advances pertaining to the neuroprotective mechanisms of NBP-derived compounds and the possibility of their clinical implementation in the management of various neurological conditions.

N-Butylphthalide Alleviates Blood-Brain Barrier Impairment in Rats Exposed to Carbon Monoxide

Carbon monoxide (CO) poisoning is one of the most important health concerns and may result in neuropathologic changes and neurologic sequelae. However, few studies have addressed the correlation between CO poisoning and blood–brain barrier (BBB) impairment. In this study, we investigated the effects of N-butylphthalide (NBP) on the expressions of zonula occludens-1 (ZO-1), claudin-5 and aquaporin-4 (AQP-4) proteins in a CO poisoning rat model. The results indicated that the brain water content was obviously increased, and the tight junctions between endothelial cells were disrupted, resulting in significant cerebral edema and BBB dysfunction in a rat model of CO poisoning. Meanwhile, the ultrastructure of endothelial cells and pericytes was seriously damaged, and the expressions of ZO-1 and claudin-5 were decreased at an early stage (<7 days). NBP treatment could efficiently maintain the ultrastructural and functional integrity of BBB, alleviate cerebral edema. Besides, NBP could also markedly increase the levels of both ZO-1 and claudin-5 proteins compared with those in rats exposed to CO (P < 0.05), whereas NBP had no apparent regulatory effect on AQP-4 expression. Taken together, this study highlights the importance of ZO-1 and claudin-5 proteins in maintaining BBB ultrastructure and function after CO poisoning. NBP, as a novel treatment approach, may effectively inhibit the down-regulation of ZO-1 and claudin-5 proteins (but not AQP-4), thereby preserving the barrier function and reducing cerebral edema after CO poisoning.

Effects of hydrogen sulfide on cognitive dysfunction and NR2B in rats

BACKGROUND

Hepatic ischemia/reperfusion (hepatic I/R) has been found to induce cognitive dysfunction. The NR2B subunit of N-methyl-D-aspartate (NMDA) receptors is a major factor in memory and learning processes, and hydrogen sulfide (H2S) may modulate this NMDA receptor. Therefore, in this study, sodium hydrosulfide (NaHS, a donor of H2S) was administered in an animal model of hepatic I/R to investigate the effects of H2S on cognitive impairment and expression of NR2B.

MATERIALS AND METHODS

NaHS (5 mg/kg) or normal saline was administered intraperitoneally once a day for 11 consecutive days, during which a rat model of 70% hepatic I/R was established on the fourth day. Cognitive function was evaluated using a Morris water maze, mRNA and protein levels of the NR2B subunit were detected in the hippocampus by RT-PCR and Western blotting. All these tests were performed on postoperative days 1, 3, 5, and 7.

RESULTS

Cognitive dysfunction was detected in the hepatic I/R group, and this dysfunction was associated with a decrease in the mRNA and protein levels of the NR2B subunit of the NMDA receptors in the hippocampus. In contrast, treatment with NaHS significantly ameliorated the impairment of cognitive function caused by hepatic I/R, and an increase in mRNA and protein levels of the NR2B subunit was detected in the corresponding hippocampus tissues.

CONCLUSIONS

The present data suggest that H2S exerts a protective effect on hepatic I/R-induced cognitive impairment, and this effect may be associated with the NR2B subunit of the NMDA receptors. H2S may represent a novel therapeutic agent for the treatment of postoperative cognitive dysfunction after liver surgery.

DL-3-n-butylphthalide delays the onset and progression of diabetic cataract by inhibiting oxidative stress in rat diabetic model

DL-3-n-butylphthalide (NBP) is a therapeutic drug used for ischemic stroke treatment. Here, we investigated the impact of NBP on the development of rat diabetic cataract induced by intraperitoneal injection of streptozotocin (STZ). NBP was then administrated by oral gavage for nine weeks. Cataract development was monitored through ophthalmoscope inspections. The levels of blood glucose and serum reactive oxygen species (ROS), malondialdehyde (MDA) and 8-Hydroxydeovexyguanosine (8-OHdG) were measured. Total and soluble protein and oxidative stress parameters, such as 2, 4- dinitrophenylhydrazone (DNP), 4-hydroxynonenal (4-HNE) and MDA in the lenses were determined by Western blot and thiobarbituric acid analyses. The expressions of NF-E2-related factor 2 (Nrf2) and its downstream antioxidant enzymes, thioredoxin (TRX), Catalase and nuclear accumulation of Nrf2 were determined by Western blot and immunohistochemistry analyses. We showed that NBP treatment significantly improved the cataract scores, the levels of DNP, 4-HNE, and MDA in the lens compared to the non-treated groups. NBP also enhanced the expressions of Nrf2, TRX and catalase in the lens of diabetic rats. In addition, NBP treatment also decreased levels of blood glucose, serum MDA and 8-OHdG. These results suggested that NBP treatment significantly delayed the onset and progression of diabetic cataract by inhibiting the oxidative stresses.

Effects of N-Butylphthalide on the expressions of Nogo/NgR in rat brain tissue after carbon monoxide poisoning

Carbon monoxide (CO) intoxication is one of the most common types of poisoning worldwide, and may result in neuropathologic sequelae, yet its pathogenesis is not clear and there is no optimal management strategy for patients with CO poisoning. In this study, the rat model of CO poisoning was established in a hyperbaric chamber by CO exposure. Rats were administered orally N-Butylphthalide (NBP) at a dose of 1 ml/100g. Neuronal apoptosis was assessed by TUNEL stain and flow cytometry. The expressions of neurite outgrowth inhibitor (Nogo), myelin-associated glycoprotein (MAG) and Nogo receptor-1 (NgR1) were observed in rat brain tissue by immunohistochemistry and double immunofluorescence staining. As we expected, CO poisoning could start the mechanism of apoptosis. The number of apoptotic cells and the early neuronal apoptosis percentage (EAR) were significantly increased at 1 day, 3 day after CO exposure. NBP treatment obviously reduce neuronal apoptosis and the EAR (P<0.05). CO poisoning could induce Nogo, MAG and NgR1 expressions. The increased Nogo, MAG and NgR1 proteins were still observed at 4 week after CO poisoning. NBP could significantly reduce the levels of Nogo and NgR1 proteins. Then we suspected that the expressions of Nogo, MAG and NGR1 proteins might be associated with brain injury and demyelination induced by CO poisoning. NBP might inhibit neuronal apoptosis and the EAR, down-regulate the expressions of Nogo and NgR1 proteins (but not MAG), and play a neuro-protective role in brain damage after acute CO poisoning.