The distinction of radiation-induced brain necrosis (RBN) and recurrent glioblastoma multiform (rGBM) remains a diagnostic challenge due to their similarly on routine follow-up imaging studies and also their clinical ...The distinction of radiation-induced brain necrosis (RBN) and recurrent glioblastoma multiform (rGBM) remains a diagnostic challenge due to their similarly on routine follow-up imaging studies and also their clinical manifestations. Our purpose of this review article is to evaluate the role of advanced MR imaging techniques such as Perfusion-weighted imaging (PWI), Diffusion-weighted imaging (DWI) and Magnetic resonance spectroscopy (MRS) in the differentiation of RBN and rGBM and their complications together with our experience and knowledge gained during our neuroimaging practice.展开更多
Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective treatment.Pyroptosis is a crucial mechanism underlying early brain injury after subarachnoid hemorrhage.Previous studies have...Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective treatment.Pyroptosis is a crucial mechanism underlying early brain injury after subarachnoid hemorrhage.Previous studies have confirmed that tumor necrosis factor-stimulated gene-6(TSG-6)can exert a neuroprotective effect by suppressing oxidative stress and apoptosis.However,no study to date has explored whether TSG-6 can alleviate pyroptosis in early brain injury after subarachnoid hemorrhage.In this study,a C57BL/6J mouse model of subarachnoid hemorrhage was established using the endovascular perforation method.Our results indicated that TSG-6 expression was predominantly detected in astrocytes,along with NLRC4 and gasdermin-D(GSDMD).The expression of NLRC4,GSDMD and its N-terminal domain(GSDMD-N),and cleaved caspase-1 was significantly enhanced after subarachnoid hemorrhage and accompanied by brain edema and neurological impairment.To explore how TSG-6 affects pyroptosis during early brain injury after subarachnoid hemorrhage,recombinant human TSG-6 or a siRNA targeting TSG-6 was injected into the cerebral ventricles.Exogenous TSG-6 administration downregulated the expression of NLRC4 and pyroptosis-associated proteins and alleviated brain edema and neurological deficits.Moreover,TSG-6 knockdown further increased the expression of NLRC4,which was accompanied by more severe astrocyte pyroptosis.In summary,our study revealed that TSG-6 provides neuroprotection against early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome activation-induced astrocyte pyroptosis.展开更多
Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of...Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of CTRP6 in cerebral ischemia/reperfusion injury associated with diabetes mellitus, a diabetes mellitus mouse model of cerebral ischemia/reperfusion injury was established by occlusion of the middle cerebral artery. To overexpress CTRP6 in the brain, an adeno-associated virus carrying CTRP6 was injected into the lateral ventricle. The result was that oxygen injury and inflammation in brain tissue were clearly attenuated, and the number of neurons was greatly reduced. In vitro experiments showed that CTRP6 knockout exacerbated oxidative damage, inflammatory reaction, and apoptosis in cerebral cortical neurons in high glucose hypoxia-simulated diabetic cerebral ischemia/reperfusion injury. CTRP6 overexpression enhanced the sirtuin-1 signaling pathway in diabetic brains after ischemia/reperfusion injury. To investigate the mechanism underlying these effects, we examined mice with depletion of brain tissue-specific sirtuin-1. CTRP6-like protection was achieved by activating the sirtuin-1 signaling pathway. Taken together, these results indicate that CTRP6 likely attenuates cerebral ischemia/reperfusion injury through activation of the sirtuin-1 signaling pathway.展开更多
To investigate the inhibiting effect of β-Aescin on nuclear factor-κB (NF-κB) activation and the expression of tumor necrosis factor-α (TNF-α) protein after traumatic brain injury (TBI) in the rat brain, 62 SD ra...To investigate the inhibiting effect of β-Aescin on nuclear factor-κB (NF-κB) activation and the expression of tumor necrosis factor-α (TNF-α) protein after traumatic brain injury (TBI) in the rat brain, 62 SD rats were subjected to lateral cortical impact injury caused by a free-falling object and divided randomly into four groups: (1) sham operated (Group A); (2) injured (Group B); (3) β-Aescin treatment (Group C); (4) pyrrolidine dithocarbamate (PDTC) treatment (Group D). β-Aescin was administered in Group C and PDTC treated in Group D immediately after injury. A series of brain samples were obtained directly 6h, 24 h and 3 d respectively after trauma in four groups. NF-κB activation was examined by Electrophoretic Mobility Shift Assay (EMSA); the levels of TNF-α protein were measured by radio-immunoassay (RIA); the water content of rat brain was measured and pathomorphological observation was carried out. NF-κB activation, the levels of TNF-α protein and the water content of rat brain were significantly increased (P<0.01) following TBI in rats. Compared with Group B, NF-κB activation (P<0.01), the levels of TNF-α protein (P<0.01) and the water content of brain (P<0.05) began to decrease obviously after injury in Groups C and D.β-Aescin could dramatically inhibit NF-κB activation and the expression of TNF-α protein in the rat brain, alleviate rat brain edema, and that could partially be the molecular mechanism by which β-Aescin attenuates traumatic brain edema.展开更多
Radiation therapy is considered the most effective non-surgical treatment for brain tumors.However,there are no available treatments for radiation-induced brain injury.Bisdemethoxycurcumin(BDMC)is a demethoxy derivati...Radiation therapy is considered the most effective non-surgical treatment for brain tumors.However,there are no available treatments for radiation-induced brain injury.Bisdemethoxycurcumin(BDMC)is a demethoxy derivative of curcumin that has anti-proliferative,anti-inflammatory,and anti-oxidant properties.To determine whether BDMC has the potential to treat radiation-induced brain injury,in this study,we established a rat model of radiation-induced brain injury by administe ring a single 30-Gy vertical dose of irradiation to the whole brain,followed by intraperitoneal injection of 500μL of a 100 mg/kg BDMC solution every day for 5 successive weeks.Our res ults showed that BDMC increased the body weight of rats with radiation-induced brain injury,improved lea rning and memory,attenuated brain edema,inhibited astrocyte activation,and reduced oxidative stress.These findings suggest that BDMC protects against radiationinduced brain injury.展开更多
BACKGROUND: Previous studies have shown that transplantation of vascular endothelial growth factor (VEGF)-modified neural stem cells (NSC) provides better outcomes, compared with neural stem cells, in the treatme...BACKGROUND: Previous studies have shown that transplantation of vascular endothelial growth factor (VEGF)-modified neural stem cells (NSC) provides better outcomes, compared with neural stem cells, in the treatment of brain damage. OBJECTIVE: To compare the effects of VEGF-modified NSC transplantation and NSC transplantation on radiation-induced brain injury, and to determine neuron-specific enolase (NSE) expression in the brain. DESIGN, TIME, AND SETTING: The randomized, controlled study was performed at the Linbaixin Experimental Center, Second Affiliated Hospital, Sun Yat-sen University, China from November 2007 to October 2008. MATERIALS: VEGF-modified C17.2 NSCs were supplied by Harvard Medical School, USA. Streptavidin-biotin-peroxidase-complex kit (Boster, China) and 5, 6-carboxyfluorescein diacetate succinimidyl ester (Fluka, USA) were used in this study. METHODS: A total of 84 Sprague Dawley rats were randomly assigned to a blank control group (n = 20), model group (n = 20), NSC group (n = 20), and a VEGF-modified NSC group (n = 24). Rat models of radiation-induced brain injury were established in the model, NSC, and VEGF-modified NSC groups. At 1 week following model induction, 10 pL (5 ×10^4 cells/μL) VEGF-modified NSCs or NSCs were respectively infused into the striatum and cerebral cortex of rats from the VEGF-modified NSC and NSC groups. A total of 10μL saline was injected into rats from the blank control and model groups. MAIN OUTCOME MEASURES: NSE expression in the brain was detected by immunohistochemistry following VEGF-modified NSC transplantation. RESULTS: NSE expression was significantly decreased in the brains of radiation-induced brain injury rats (P 〈 0.05). The number of NSE-positive neurons significantly increased in the NSC and VEGF-modified NSC groups, compared with the model group (P 〈 0.05). NSE expression significantly increased in the VEGF-modified NSC group, compared with the NSC group, at 6 weeks following transplantation (P 〈 0.05). CONCLUSION: VEGF-modified NSC transplantation increased NSE expression in rats with radiation-induced brain injury, and the outcomes were superior to NSC transplantation.展开更多
A 61-year-old female nasopharyngeal carcinoma patient was admitted to the hospital with sudden cognitive dysfunction one month after Volumetric Intensity Modulated Arc Therapy(VMAT)conventional dose radiotherapy,and t...A 61-year-old female nasopharyngeal carcinoma patient was admitted to the hospital with sudden cognitive dysfunction one month after Volumetric Intensity Modulated Arc Therapy(VMAT)conventional dose radiotherapy,and the initial diagnosis was radiation-induced brain injury(RBI).After comprehensive treatment with steroid hormones,the patient’s condition rapidly improved.Typically,in nasopharyngeal carcinoma patients treated with VMAT,the incidence of RBI is extremely low when the temporal lobe dose is less than 65 Gy or 1%of the volume is less than 65 Gy.When this limit is exceeded,RBI may occur in varying degrees.However,in this case,even though the temporal lobe dose was under the prescribed limit,the patient still experienced RBI.The rare observations in this case can be used as a reference,and clinicians should seriously consider the possibility of RBI in similar cases.展开更多
Malignant tumors are one of the serious public health problems that threaten the survival time of human beings.They are prone to metastasis to distant organs and the central nervous system is one of the common target ...Malignant tumors are one of the serious public health problems that threaten the survival time of human beings.They are prone to metastasis to distant organs and the central nervous system is one of the common target organs.As it is difficult for chemotherapeutics,targeted drugs and other macromolecules to pass through the blood brain barrier(BBB),local radiation therapy is often used for treating intracranial primary or metastatic tumors.However,whether it is whole brain radiation therapy(WBRT)or stereotactic body radiation therapy(SBRT),the choice of radiation dose is limited by the side effects of radiation therapy on the surrounding normal brain tissues.Radiation-induced brain injury(RBI)can further develop into radiation necrosis(RN)in the late stage.Bevacizumab is often effective against RBI by antagonizing vascular endothelial growth factor(VEGF),but it still cannot completely reverse RN.Emerging treatment options such as human pluripotent stem-cell transplantation have made it possible to reverse the process of RN.展开更多
The focal and diffuse cerebral white matter injury can be caused by treatment with radiation therapy for cranial tumors. However, the literature rarely describes a MRI finding in radiation-induced delayed extensive ce...The focal and diffuse cerebral white matter injury can be caused by treatment with radiation therapy for cranial tumors. However, the literature rarely describes a MRI finding in radiation-induced delayed extensive cerebral injury. Our objective was to report a rare case who had a delayed extensive hyperintensity injury in brain on MRI after radiation therapy due to nasopharyngeal cancer. A MRI was performed on a 40-year-old patient with extensive brain damage who had the radiation therapy two years ago.MRI finding was evaluated. On MRI, T2-weighted MRI showed an extensive hyperintensity after treated by irradiation. The radiographic pattern of extensive cerebral injury is relatively distinct. It involves the white matter and gray matter in cerebral, cerebellum, medulla oblongata, pons, internal capsule and thalamus bilaterally. Our observations demonstrate that the extensive hyperintensity lesions in brain on MRI after radiation therapy is a cortical laminar necrosis and white matter myelinolysis.展开更多
Neuropathic pain is a chronic syndrome caused by direct damage to or disease of the somatosensory nervous system. The lack of safe, adequate and sustained pain relief offered by present analgesic treatments is most al...Neuropathic pain is a chronic syndrome caused by direct damage to or disease of the somatosensory nervous system. The lack of safe, adequate and sustained pain relief offered by present analgesic treatments is most alarming. While many treatment options are available to manage chronic pain, such as antidepressants, nonsteroidal anti-inflammatory agents, opioids, and anticonvulsants, chronic neuropathic pain remains largely unmanaged. Compounding the dilemma of ineffective chronic pain treatments is the need to provide relief from suffering and yet not contribute to the scourge of drug abuse. A recent epidemic of addiction and accidental drug prescription overdoses parallel the increased use of opioid treatment, even though opioids are rarely an effective treatment of relieving chronic pain. To make matters worse, opioids may contribute to exacerbating pain, and side-effects such as cognitive impairment, nausea, constipation, development of tolerance, as well as their potential for addiction and overdose deaths exist. Clearly, there is an urgent need for alternative, nonopiate treatment of chronic pain. Innovative discoveries of pertinent brain mechanisms and functions are key to developing effective, safe treatments. Pioneering work has revealed the essential effects of the pleiotropic mediator tumor necrosis factor(TNF) on brain functioning. These studies establish that TNF inhibits norepinephrine release from hippocampal neurons, and show that excess TNF production within the hippocampus occurs during neuropathic pain, which mobilizes additional mechanisms that further inhibit norepinephrine release. Significantly, it has been verified that elevated levels of TNF in the brain are actually required for neuropathic pain development. Since TNF decreases norepinephrine release in the brain, enhanced TNF levels would prevent engagement of the norepinephrine descending inhibitory neuronal pain pathways. Increased levels of TNF in the brain are therefore critical to the development of neuropathic pain. Therefore, strategies that decrease this enhanced TNF expression in the brain will have superior analgesic efficacy. We propose this novel approach of targeting the pathologically high levels of brain TNF as an effective strategy in the treatment of the devastating syndrome of chronic pain.展开更多
Summary: The changes of tumor necrosis factor-α (TNF-α) and brain ultrastructure during cardiopulmonary resuscitation and the effects of ulinastation injection were observed, and the mechanism was investigated. Twen...Summary: The changes of tumor necrosis factor-α (TNF-α) and brain ultrastructure during cardiopulmonary resuscitation and the effects of ulinastation injection were observed, and the mechanism was investigated. Twenty-four adult healthy Sprague-Dawley rats were randomly divided into control group (8 rats), resuscitation group (8 rats) and ulinastatin (UTI) group (8 rats). Rats in control group underwent tracheotomy without clipping the trachea to induce circulatory and respiratory standstill. Rats in resuscitation and ulinastatin group were subjected to the procedure of establishing the model of cardiopulmonary cerebral resuscitation (CPCR). Rats in ulinastatin group were given with UTI 104 U/kg once after CPCR. In the control group, the plasma was collected immediate, 30 min, 2 h, 4 h, and 6 h after tracheotomy. In resuscitation group and UTI group, plasma was collected immediate after tracheotomy, 30 min, 2 h, 4 h and 6 h after successful resuscitation. The plasma levels of TNF-α were determined by radioimmunoassay (RIA). At the end of the experiment, 2 rats were randomly selected from each group and were decapitated. The cortex of the brain was taken out immediately to observe the ultrastructure changes. In control group, there were no significant differences in the level of TNF-α among different time points (P>0.05). In resuscitation group, the level of TNF-α was increased obviously after resuscitation (P<0.01) and reached its peak 2 h later after resuscitation. An increasing trend of TNF-α showed in UTI group. There were no differences in TNF-α among each sample taken after successful resuscitation and that after tracheotomy. The utrastructure of brains showed the injury in UTI group was ameliorated as compared with that in resuscitation group. In early period of CPCR, TNF-α was expressed rapidly and kept increasing. It indicated that TNF-α might take part in the tissue injury after CPCR. The administration of UTI during CACR could depress TNF-α and ameliorate brain injury. By regulating the expression of damaging mediator, UTI might provide a protective effect on the tissue injury after CPCR.展开更多
We established a rat model of cardiac arrest by clamping the endotracheal tube of adult rats at expiration. Twenty-four hours after cardiopulmonary resuscitation, nerve cell injury and expression of tumor necrosis fac...We established a rat model of cardiac arrest by clamping the endotracheal tube of adult rats at expiration. Twenty-four hours after cardiopulmonary resuscitation, nerve cell injury and expression of tumor necrosis factor-α, interleukin-1β, and p38 mitogen activated protein kinase content were increased. Rats injected with Xuebijing, a Chinese herb compound preparation, exhibited normal cellular structure and morphology, dense neuronal cytoplasm, and decreased tumor necrosis factor-α, interleukin-1β, and p38 mitogen activated protein kinase expression at 24 hours following cardiopulmonary resuscitation. These data suggest that Xuebijing can attenuate neuronal injury induced by hypoxia and reperfusion during cardiopulmonary resuscitation.展开更多
Inflammatory processes and proinflammatory cytokines have a key role in the cellular processes of neurodegenerative diseases and are linked to the pathogenesis of functional and mental health disorders.Tumor necrosis ...Inflammatory processes and proinflammatory cytokines have a key role in the cellular processes of neurodegenerative diseases and are linked to the pathogenesis of functional and mental health disorders.Tumor necrosis factor alpha has been reported to play a major role in the central nervous system in Alzheimer’s disease,Parkinson’s disease and amyotrophic lateral sclerosis and many other neurodegenerative diseases.Therefore,a potent proinflammatory/proapoptotic tumor necrosis factor alpha could be a strong candidate for targeted therapy.Plant derivatives have now become promising candidates as therapeutic agents because of their antioxidant and chemical characteristics,and anti-inflammatory features.Recently,phytochemicals including flavonoids,terpenoids,alkaloids,and lignans have generated interest as tumor necrosis factor alpha inhibitor candidates for a number of diseases involving inflammation within the nervous system.In this review,we discuss how phytochemicals as tumor necrosis factor alpha inhibitors are a therapeutic strategy targeting neurodegeneration.展开更多
BACKGROUND: Numerous studies have shown that tumor necrosis factor α (TNF-α) is closely correlated with spinal cord injury (SCI), but the mechanisms of TNF-α and therapeutic treatments for SCI are still poorly...BACKGROUND: Numerous studies have shown that tumor necrosis factor α (TNF-α) is closely correlated with spinal cord injury (SCI), but the mechanisms of TNF-α and therapeutic treatments for SCI are still poorly understood. OBJECTIVE: To determine the role of TNF-α in the pathogenesis of SCI. DESIGN, TIME AND SETTING: An in vivo experiment based on genetically engineered animals was performed at the Medical University of South Carolina, Charleston, South Carolina, USA, between June 2007 and October 2008. MATERIALS: TNF-α transgenic rats (Xenogen Biosciences in Cranbury, New Jersey, USA) were utilized in this study. METHODS: TNF-α transgenic (tg) and wild-type (WT) rats underwent a complete single-level laminectomy at the 10^th thoracic vertebra (T10). MAIN OUTCOME MEASURES: Motor function of rat hindlimb was assessed using the Basso, Beattie, and Bresnahan hindlimb locomotor rating scale. Histological evaluation of spinal cord tissue loss was conducted. Immunohistochemistry for astrocytes, microglia/macrophages, and TNF receptors (TNFRs) was performed on spinal cord tissue sections. TNF-α mRNA expression was detected by real-time polymerase chain reaction. The concentrations of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in the supernatant were determined using an enzyme-linked immunosorbent assay kit for rat NGF or BDNF, respectively. The rats were injected subcutaneously with etanercept to verify that TNF-α was the direct effect of the modulation of behavioral and neurodegenerative outcomes in the TNF-α tg rats. RESULTS: TNF-α tg rats showed higher expression of TNF-α mRNA in the spinal cord prior to SCI. TNF-α tg rats showed worse motor deficits than WT rats in the acute period (〈 3 days) after SCI (P 〈 0.01), while in the chronic period, TNF-α tg rats exhibited persistent elevated baseline levels of TNF-α mRNA and improved recovery in motor function and tissue healing compared to WT rats (P 〈 0.01 ). Following SCI, the number of microglia/macrophages in TNF-α tg rat was always greater than in WT rat (P 〈 0.01). There were no significant differences in NGF and BDNF levels in the supernatant of spinal cord homogenates. TNFR1 expression was significantly greater in the TNF-α tg rats compared to the WT rats (P 〈 0.01). However, TNFR2 expression did not reveal a significant increase in the TNF-α tg rats compared to the WT rats. Finally, treatment with etanercept reduced injury acutely, but exacerbated the injury chronically. CONCLUSION: Overexpression of TNF-α is deleterious in the acute phase, but beneficial in the chronic phase in the response to SCI. The role of TNF-α post-injury may depend on TNF-α expression in the spinal cord and its differential binding to TNFRI. Our observations may have clinical relevance that antagonists or inhibitors of TNF-α could be administered within the early time window post-injury, and appropriate amounts of TNF-α could be administered during the chronic stage, in order to improve the final neurological recovery in patients with SCI.展开更多
Ischemic brain injury triggers neuronal cell death by apoptosis via caspase activation and by necroptosis through activation of the receptor-interacting protein kinases (RIPK) associated with the tumor necrosis fact...Ischemic brain injury triggers neuronal cell death by apoptosis via caspase activation and by necroptosis through activation of the receptor-interacting protein kinases (RIPK) associated with the tumor necrosis factor-alpha (TNF-a)/death receptor. Recent evidence shows RIPK inhibitors are neuroprotective and al- leviate ischemic brain injury in a number of animal models, however, most have not yet undergone clinical trials and safety in humans remains in question. Dabrafenib, originally identified as a B-raf inhibitor that is currently used to treat melanoma, was later revealed to be a potent RIPK3 inhibitor at micromolar con- centrations. Here, we investigated whether Dabrafenib would show a similar neuroprotective effect in mice subjected to ischemic brain injury by photothrombosis. Dabrafenib administered intraperitoneally at 10 mg/ kg one hour after photothrombosis-induced focal ischemic injury significantly reduced infarct lesion size in C57BL6 mice the following day, accompanied by a markedly attenuated upregulation of TNF-u. However, subsequent lower doses (5 mg/kg/day) failed to sustain this neuroprotective effect after 4 days. Dabrafenib bl ocked lipopolysaccharides-induced activation of TNF-ct in bone marrow-derived macrophages, suggesting that Dabrafenib may attenuate TNF-ct-induced necroptotic pathway after ischemic brain injury. Since Dab- rafenib is already in clinical use for the treatment of melanoma, it might be repurposed for stroke therapy.展开更多
Puerarin, a traditional Chinese medicine, exerts a powerful neuroprotective effect in cerebral ischemia/reperfusion injury, but its mechanism is unknown. Here, we established rat models of middle cerebral artery ische...Puerarin, a traditional Chinese medicine, exerts a powerful neuroprotective effect in cerebral ischemia/reperfusion injury, but its mechanism is unknown. Here, we established rat models of middle cerebral artery ischemia/reperfusion injury using the suture method. Puerarin (100 mg/kg) was administered intraperitoneally 30 minutes before middle cerebral artery occlusion and 8 hours after reperfusion. Twenty-four hours after reperfusion, we found that puerarin significantly improved neurological deficit, reduced infarct size and brain water content, and notably diminished the expression of Toll-like receptor-4, myeloid differentiation factor 88, nuclear factor kappa B and tumor necrosis factor-α in the ischemic region. These data indicate that puerarin exerts an anti-inflammatory protective effect on brain tissue with ischemia/reperfusion damage by downregulating the expression of multiple inflammatory factors.展开更多
Previous studies have shown that vagus nerve stimulation can improve the prognosis of trau- matic brain injury. The aim of this study was to elucidate the mechanism of the neuroprotective effects of vagus nerve stimul...Previous studies have shown that vagus nerve stimulation can improve the prognosis of trau- matic brain injury. The aim of this study was to elucidate the mechanism of the neuroprotective effects of vagus nerve stimulation in rabbits with brain explosive injury. Rabbits with brain ex- plosive injury received continuous stimulation (10 V, 5 Hz, 5 ms, 20 minutes) of the right cervical vagus nerve. Tumor necrosis factor-a, interleukin-l~ and interleukin-10 concentrations were detected in serum and brain tissues, and water content in brain tissues was measured. Results showed that vagus nerve stimulation could reduce the degree of brain edema, decrease tumor necrosis factor-a and interleukin-1β concentrations, and increase interleukin-10 concentration after brain explosive injury in rabbits. These data suggest that vagus nerve stimulation may exert neuroprotective effects against explosive injury via regulating the expression of tumor necrosis factor-a, interleukin-1 β and interleukin-10 in the serum and brain tissue.展开更多
Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Berberine, the effective ingredient of Coptidis Rhizoma and Cortex Phellodendti...Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Berberine, the effective ingredient of Coptidis Rhizoma and Cortex Phellodendti, has a wide range of pharmacological functions, including anti-inflammatory, anti-atherosclerotic and anti-cancer effects. The neuroprotective potential of berberine has previously been demonstrated. The present study aimed to examine whether berberine could repress microglial activation and can be considered a potential therapeutic candidate to target neurodegenerative diseases. Primary microglial cells and BV2 microglial cells were cultured and stimulated with bacterial lipopolysaccharide (LPS). Berberine chloride was treated prior to LPS or simultaneously with LPS stimulation. Results revealed that berberine was effective at inhibiting nitric oxide release from primary microglial cells when cells were exposed to the compound prior to LPS or simultaneously with LPS. It also reduced the LPS-stimulated production of tumor necrosis factor-α, interleukin-1β, prostaglandin E2, and intracellular reactive oxygen species and nuclear factor-kappa activation. Additionally, berberine reduced nitric oxide release from microglia stimulated with interferon-γ and amyloid β. These results suggest that berberine provides neuroprotection by reducing the production of various neurotoxic molecules from activated microglia.展开更多
BACKGROUND: Certain components of tetramethylpyrazine, a traditional Chinese medicine, exhibit protective effects against brain injury. OBJECTIVE: To investigate the effects of different Naoxintong doses on expressi...BACKGROUND: Certain components of tetramethylpyrazine, a traditional Chinese medicine, exhibit protective effects against brain injury. OBJECTIVE: To investigate the effects of different Naoxintong doses on expression of nuclear factor-kappa B ( kB), interleukin-6, tumor necrosis factor-α, and complement 3 in rats following focal cerebral ischemia. DESIGN, TIME AND SETTING: The randomized experiment was performed at the Laboratory of Neurology, Second Hospital of Hebei Medical University from June 2004 to June 2006. MATERIALS: A total of 150 adult, healthy, male, Sprague Dawley rats, weighing 280-320g, were selected. Naoxintong powder (mainly comprising szechwan lovage rhizome, milkvetch root, danshen root, and radix angelicae sinensis) was obtained from Buchang Pharmacy Co., Ltd. in Xianyang City of Shanxi Province of China, lot number 040608. METHODS: The rats were randomly assigned into sham operation, saline, high-dose Naoxintong, moderate-dose Naoxintong, and low-dose Naoxintong groups, with 30 rats in each group. Rat models of middle cerebral artery occlusion were established using the suture method, with the exception of the sham operation group. Rats in the high-dose, moderate-dose and low-dose Naoxintong groups received 4, 2, and 1 g/kg Naoxintong respectively, by gavage. Rats in the saline group were treated with 1 mL saline by gavage All rats were administered by gavage at 5 and 23 hours following surgery, and subsequently, once per day. MAIN OUTCOME MEASURES: At 6, 24, 48, 72 hours, and 7 days following model establishment, brain water content was measured. Histopathological changes in brain tissues were detected using hematoxylin-eosin staining. Expression of nuclear factor- kB, interleukin-6, tumor necrosis factor- α, and complement 3 was examined by immunohistochemistry. RESULTS: A total of 150 rats were included in the final analysis with no loss. Brain water content was significantly increased in the ischemic hemisphere of rats from the saline, as well as the high-dose, moderate-dose, and low-dose Naoxintong groups at 24 hours, which reached a peak at 48 hours. At 6, 24, 48, 72 hours, and 7 days, brain water content was greater in the ischemic hemisphere of rats from the saline, as well as the high-dose, moderate-dose, and low-dose Naoxintong groups, compared with the sham operation group (P 〈 0.05). At 24 and 48 hours, brain water content was reduced in the high-dose and moderate-dose Naoxintong groups, compared to the saline and low-dose Naoxintong groups (P 〈 0.05). In the saline, as well as high-dose, moderate-dose, and low-dose Naoxintong groups, neuronal edema was observed at 6 hours surrounding the ischemic sites. Inflammatory cells appeared at 24 hours, reached a peak at 48 hours, and gradually diminished. A small amount of glial cell proliferation and neuronal degeneration were observed in the hippocampus at 72 hours following infarction. Microglial proliferation and aggregation were detected at 7 days after infarction. Expression of nuclear factor- kB, interleukin-6, tumor necrosis factor-α, and complement 3 was significantly less in the high-dose, moderate-dose, and low-dose Naoxintong groups, compared to the sham operation group (P 〈 0.05). Expression of the above-mentioned inflammatory cytokines was lower in rat brain tissues of the high-dose Naoxintong group, compared to the low-dose Naoxintong group (P 〈 0.05). CONCLUSION: High-dose Naoxintong and moderate-dose Naoxintong significantly alleviated rat brain edema and decreased expression of nuclear factor-kB, interleukin-6, tumor necrosis factor-α, and complement 3 in brain tissues. The protective effect of high-dose Naoxintong was most significant.展开更多
文摘The distinction of radiation-induced brain necrosis (RBN) and recurrent glioblastoma multiform (rGBM) remains a diagnostic challenge due to their similarly on routine follow-up imaging studies and also their clinical manifestations. Our purpose of this review article is to evaluate the role of advanced MR imaging techniques such as Perfusion-weighted imaging (PWI), Diffusion-weighted imaging (DWI) and Magnetic resonance spectroscopy (MRS) in the differentiation of RBN and rGBM and their complications together with our experience and knowledge gained during our neuroimaging practice.
基金supported the National Natural Science Foundation of China,No.81974178(to CD).
文摘Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective treatment.Pyroptosis is a crucial mechanism underlying early brain injury after subarachnoid hemorrhage.Previous studies have confirmed that tumor necrosis factor-stimulated gene-6(TSG-6)can exert a neuroprotective effect by suppressing oxidative stress and apoptosis.However,no study to date has explored whether TSG-6 can alleviate pyroptosis in early brain injury after subarachnoid hemorrhage.In this study,a C57BL/6J mouse model of subarachnoid hemorrhage was established using the endovascular perforation method.Our results indicated that TSG-6 expression was predominantly detected in astrocytes,along with NLRC4 and gasdermin-D(GSDMD).The expression of NLRC4,GSDMD and its N-terminal domain(GSDMD-N),and cleaved caspase-1 was significantly enhanced after subarachnoid hemorrhage and accompanied by brain edema and neurological impairment.To explore how TSG-6 affects pyroptosis during early brain injury after subarachnoid hemorrhage,recombinant human TSG-6 or a siRNA targeting TSG-6 was injected into the cerebral ventricles.Exogenous TSG-6 administration downregulated the expression of NLRC4 and pyroptosis-associated proteins and alleviated brain edema and neurological deficits.Moreover,TSG-6 knockdown further increased the expression of NLRC4,which was accompanied by more severe astrocyte pyroptosis.In summary,our study revealed that TSG-6 provides neuroprotection against early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome activation-induced astrocyte pyroptosis.
基金supported by the National Natural Science Foundation of China,Nos.82102295(to WG),82071339(to LG),82001119(to JH),and 81901994(to BZ).
文摘Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of CTRP6 in cerebral ischemia/reperfusion injury associated with diabetes mellitus, a diabetes mellitus mouse model of cerebral ischemia/reperfusion injury was established by occlusion of the middle cerebral artery. To overexpress CTRP6 in the brain, an adeno-associated virus carrying CTRP6 was injected into the lateral ventricle. The result was that oxygen injury and inflammation in brain tissue were clearly attenuated, and the number of neurons was greatly reduced. In vitro experiments showed that CTRP6 knockout exacerbated oxidative damage, inflammatory reaction, and apoptosis in cerebral cortical neurons in high glucose hypoxia-simulated diabetic cerebral ischemia/reperfusion injury. CTRP6 overexpression enhanced the sirtuin-1 signaling pathway in diabetic brains after ischemia/reperfusion injury. To investigate the mechanism underlying these effects, we examined mice with depletion of brain tissue-specific sirtuin-1. CTRP6-like protection was achieved by activating the sirtuin-1 signaling pathway. Taken together, these results indicate that CTRP6 likely attenuates cerebral ischemia/reperfusion injury through activation of the sirtuin-1 signaling pathway.
文摘To investigate the inhibiting effect of β-Aescin on nuclear factor-κB (NF-κB) activation and the expression of tumor necrosis factor-α (TNF-α) protein after traumatic brain injury (TBI) in the rat brain, 62 SD rats were subjected to lateral cortical impact injury caused by a free-falling object and divided randomly into four groups: (1) sham operated (Group A); (2) injured (Group B); (3) β-Aescin treatment (Group C); (4) pyrrolidine dithocarbamate (PDTC) treatment (Group D). β-Aescin was administered in Group C and PDTC treated in Group D immediately after injury. A series of brain samples were obtained directly 6h, 24 h and 3 d respectively after trauma in four groups. NF-κB activation was examined by Electrophoretic Mobility Shift Assay (EMSA); the levels of TNF-α protein were measured by radio-immunoassay (RIA); the water content of rat brain was measured and pathomorphological observation was carried out. NF-κB activation, the levels of TNF-α protein and the water content of rat brain were significantly increased (P<0.01) following TBI in rats. Compared with Group B, NF-κB activation (P<0.01), the levels of TNF-α protein (P<0.01) and the water content of brain (P<0.05) began to decrease obviously after injury in Groups C and D.β-Aescin could dramatically inhibit NF-κB activation and the expression of TNF-α protein in the rat brain, alleviate rat brain edema, and that could partially be the molecular mechanism by which β-Aescin attenuates traumatic brain edema.
基金supported by the National Natural Science Foundation of China,No.82002400(to GJZ)Scientific Research Project of Hu nan Health Committee,No.20201911and No.20200469(both to ZJX)+2 种基金Scientific Research Project of Hunan Health Committee,No.20211411761(to HMW)the Natural Science Foundation of Hunan Province,No.2020JJ5512(to GJZ)a grant from Clinical Medical Technology Innovation Guidance Project in Hunan Province,No.2020SK51822(to ZJX)。
文摘Radiation therapy is considered the most effective non-surgical treatment for brain tumors.However,there are no available treatments for radiation-induced brain injury.Bisdemethoxycurcumin(BDMC)is a demethoxy derivative of curcumin that has anti-proliferative,anti-inflammatory,and anti-oxidant properties.To determine whether BDMC has the potential to treat radiation-induced brain injury,in this study,we established a rat model of radiation-induced brain injury by administe ring a single 30-Gy vertical dose of irradiation to the whole brain,followed by intraperitoneal injection of 500μL of a 100 mg/kg BDMC solution every day for 5 successive weeks.Our res ults showed that BDMC increased the body weight of rats with radiation-induced brain injury,improved lea rning and memory,attenuated brain edema,inhibited astrocyte activation,and reduced oxidative stress.These findings suggest that BDMC protects against radiationinduced brain injury.
基金Supported by:the National Natural Science Foundation of China,No.30870750the Doctor Priming Program of Natural Foundation of Guangdong Province,No. 8451008901000672+1 种基金the Medical Scientific Research Foundation Program of Guangdong Province,No. B2008044the Youth Teacher Foundation Program of Sun Yat-sen University, No,3177915
文摘BACKGROUND: Previous studies have shown that transplantation of vascular endothelial growth factor (VEGF)-modified neural stem cells (NSC) provides better outcomes, compared with neural stem cells, in the treatment of brain damage. OBJECTIVE: To compare the effects of VEGF-modified NSC transplantation and NSC transplantation on radiation-induced brain injury, and to determine neuron-specific enolase (NSE) expression in the brain. DESIGN, TIME, AND SETTING: The randomized, controlled study was performed at the Linbaixin Experimental Center, Second Affiliated Hospital, Sun Yat-sen University, China from November 2007 to October 2008. MATERIALS: VEGF-modified C17.2 NSCs were supplied by Harvard Medical School, USA. Streptavidin-biotin-peroxidase-complex kit (Boster, China) and 5, 6-carboxyfluorescein diacetate succinimidyl ester (Fluka, USA) were used in this study. METHODS: A total of 84 Sprague Dawley rats were randomly assigned to a blank control group (n = 20), model group (n = 20), NSC group (n = 20), and a VEGF-modified NSC group (n = 24). Rat models of radiation-induced brain injury were established in the model, NSC, and VEGF-modified NSC groups. At 1 week following model induction, 10 pL (5 ×10^4 cells/μL) VEGF-modified NSCs or NSCs were respectively infused into the striatum and cerebral cortex of rats from the VEGF-modified NSC and NSC groups. A total of 10μL saline was injected into rats from the blank control and model groups. MAIN OUTCOME MEASURES: NSE expression in the brain was detected by immunohistochemistry following VEGF-modified NSC transplantation. RESULTS: NSE expression was significantly decreased in the brains of radiation-induced brain injury rats (P 〈 0.05). The number of NSE-positive neurons significantly increased in the NSC and VEGF-modified NSC groups, compared with the model group (P 〈 0.05). NSE expression significantly increased in the VEGF-modified NSC group, compared with the NSC group, at 6 weeks following transplantation (P 〈 0.05). CONCLUSION: VEGF-modified NSC transplantation increased NSE expression in rats with radiation-induced brain injury, and the outcomes were superior to NSC transplantation.
基金Supported by grants from the Sichuan Medical Research Youth Innovation Project(No.Q18031)the 2018 City School Strategic Cooperation Research Project(No.18SXHZ0542)。
文摘A 61-year-old female nasopharyngeal carcinoma patient was admitted to the hospital with sudden cognitive dysfunction one month after Volumetric Intensity Modulated Arc Therapy(VMAT)conventional dose radiotherapy,and the initial diagnosis was radiation-induced brain injury(RBI).After comprehensive treatment with steroid hormones,the patient’s condition rapidly improved.Typically,in nasopharyngeal carcinoma patients treated with VMAT,the incidence of RBI is extremely low when the temporal lobe dose is less than 65 Gy or 1%of the volume is less than 65 Gy.When this limit is exceeded,RBI may occur in varying degrees.However,in this case,even though the temporal lobe dose was under the prescribed limit,the patient still experienced RBI.The rare observations in this case can be used as a reference,and clinicians should seriously consider the possibility of RBI in similar cases.
文摘Malignant tumors are one of the serious public health problems that threaten the survival time of human beings.They are prone to metastasis to distant organs and the central nervous system is one of the common target organs.As it is difficult for chemotherapeutics,targeted drugs and other macromolecules to pass through the blood brain barrier(BBB),local radiation therapy is often used for treating intracranial primary or metastatic tumors.However,whether it is whole brain radiation therapy(WBRT)or stereotactic body radiation therapy(SBRT),the choice of radiation dose is limited by the side effects of radiation therapy on the surrounding normal brain tissues.Radiation-induced brain injury(RBI)can further develop into radiation necrosis(RN)in the late stage.Bevacizumab is often effective against RBI by antagonizing vascular endothelial growth factor(VEGF),but it still cannot completely reverse RN.Emerging treatment options such as human pluripotent stem-cell transplantation have made it possible to reverse the process of RN.
文摘The focal and diffuse cerebral white matter injury can be caused by treatment with radiation therapy for cranial tumors. However, the literature rarely describes a MRI finding in radiation-induced delayed extensive cerebral injury. Our objective was to report a rare case who had a delayed extensive hyperintensity injury in brain on MRI after radiation therapy due to nasopharyngeal cancer. A MRI was performed on a 40-year-old patient with extensive brain damage who had the radiation therapy two years ago.MRI finding was evaluated. On MRI, T2-weighted MRI showed an extensive hyperintensity after treated by irradiation. The radiographic pattern of extensive cerebral injury is relatively distinct. It involves the white matter and gray matter in cerebral, cerebellum, medulla oblongata, pons, internal capsule and thalamus bilaterally. Our observations demonstrate that the extensive hyperintensity lesions in brain on MRI after radiation therapy is a cortical laminar necrosis and white matter myelinolysis.
文摘Neuropathic pain is a chronic syndrome caused by direct damage to or disease of the somatosensory nervous system. The lack of safe, adequate and sustained pain relief offered by present analgesic treatments is most alarming. While many treatment options are available to manage chronic pain, such as antidepressants, nonsteroidal anti-inflammatory agents, opioids, and anticonvulsants, chronic neuropathic pain remains largely unmanaged. Compounding the dilemma of ineffective chronic pain treatments is the need to provide relief from suffering and yet not contribute to the scourge of drug abuse. A recent epidemic of addiction and accidental drug prescription overdoses parallel the increased use of opioid treatment, even though opioids are rarely an effective treatment of relieving chronic pain. To make matters worse, opioids may contribute to exacerbating pain, and side-effects such as cognitive impairment, nausea, constipation, development of tolerance, as well as their potential for addiction and overdose deaths exist. Clearly, there is an urgent need for alternative, nonopiate treatment of chronic pain. Innovative discoveries of pertinent brain mechanisms and functions are key to developing effective, safe treatments. Pioneering work has revealed the essential effects of the pleiotropic mediator tumor necrosis factor(TNF) on brain functioning. These studies establish that TNF inhibits norepinephrine release from hippocampal neurons, and show that excess TNF production within the hippocampus occurs during neuropathic pain, which mobilizes additional mechanisms that further inhibit norepinephrine release. Significantly, it has been verified that elevated levels of TNF in the brain are actually required for neuropathic pain development. Since TNF decreases norepinephrine release in the brain, enhanced TNF levels would prevent engagement of the norepinephrine descending inhibitory neuronal pain pathways. Increased levels of TNF in the brain are therefore critical to the development of neuropathic pain. Therefore, strategies that decrease this enhanced TNF expression in the brain will have superior analgesic efficacy. We propose this novel approach of targeting the pathologically high levels of brain TNF as an effective strategy in the treatment of the devastating syndrome of chronic pain.
文摘Summary: The changes of tumor necrosis factor-α (TNF-α) and brain ultrastructure during cardiopulmonary resuscitation and the effects of ulinastation injection were observed, and the mechanism was investigated. Twenty-four adult healthy Sprague-Dawley rats were randomly divided into control group (8 rats), resuscitation group (8 rats) and ulinastatin (UTI) group (8 rats). Rats in control group underwent tracheotomy without clipping the trachea to induce circulatory and respiratory standstill. Rats in resuscitation and ulinastatin group were subjected to the procedure of establishing the model of cardiopulmonary cerebral resuscitation (CPCR). Rats in ulinastatin group were given with UTI 104 U/kg once after CPCR. In the control group, the plasma was collected immediate, 30 min, 2 h, 4 h, and 6 h after tracheotomy. In resuscitation group and UTI group, plasma was collected immediate after tracheotomy, 30 min, 2 h, 4 h and 6 h after successful resuscitation. The plasma levels of TNF-α were determined by radioimmunoassay (RIA). At the end of the experiment, 2 rats were randomly selected from each group and were decapitated. The cortex of the brain was taken out immediately to observe the ultrastructure changes. In control group, there were no significant differences in the level of TNF-α among different time points (P>0.05). In resuscitation group, the level of TNF-α was increased obviously after resuscitation (P<0.01) and reached its peak 2 h later after resuscitation. An increasing trend of TNF-α showed in UTI group. There were no differences in TNF-α among each sample taken after successful resuscitation and that after tracheotomy. The utrastructure of brains showed the injury in UTI group was ameliorated as compared with that in resuscitation group. In early period of CPCR, TNF-α was expressed rapidly and kept increasing. It indicated that TNF-α might take part in the tissue injury after CPCR. The administration of UTI during CACR could depress TNF-α and ameliorate brain injury. By regulating the expression of damaging mediator, UTI might provide a protective effect on the tissue injury after CPCR.
基金a grant from the Science and Technology Department of Jilin Province,No. 200705172
文摘We established a rat model of cardiac arrest by clamping the endotracheal tube of adult rats at expiration. Twenty-four hours after cardiopulmonary resuscitation, nerve cell injury and expression of tumor necrosis factor-α, interleukin-1β, and p38 mitogen activated protein kinase content were increased. Rats injected with Xuebijing, a Chinese herb compound preparation, exhibited normal cellular structure and morphology, dense neuronal cytoplasm, and decreased tumor necrosis factor-α, interleukin-1β, and p38 mitogen activated protein kinase expression at 24 hours following cardiopulmonary resuscitation. These data suggest that Xuebijing can attenuate neuronal injury induced by hypoxia and reperfusion during cardiopulmonary resuscitation.
文摘Inflammatory processes and proinflammatory cytokines have a key role in the cellular processes of neurodegenerative diseases and are linked to the pathogenesis of functional and mental health disorders.Tumor necrosis factor alpha has been reported to play a major role in the central nervous system in Alzheimer’s disease,Parkinson’s disease and amyotrophic lateral sclerosis and many other neurodegenerative diseases.Therefore,a potent proinflammatory/proapoptotic tumor necrosis factor alpha could be a strong candidate for targeted therapy.Plant derivatives have now become promising candidates as therapeutic agents because of their antioxidant and chemical characteristics,and anti-inflammatory features.Recently,phytochemicals including flavonoids,terpenoids,alkaloids,and lignans have generated interest as tumor necrosis factor alpha inhibitor candidates for a number of diseases involving inflammation within the nervous system.In this review,we discuss how phytochemicals as tumor necrosis factor alpha inhibitors are a therapeutic strategy targeting neurodegeneration.
基金the ES016774-01A1VA Merit Award and National Science Foundation EPSCoR grant, No. EPS-0132573+1 种基金EPS-0447660 (MSK)NS050452-05 (JJH)
文摘BACKGROUND: Numerous studies have shown that tumor necrosis factor α (TNF-α) is closely correlated with spinal cord injury (SCI), but the mechanisms of TNF-α and therapeutic treatments for SCI are still poorly understood. OBJECTIVE: To determine the role of TNF-α in the pathogenesis of SCI. DESIGN, TIME AND SETTING: An in vivo experiment based on genetically engineered animals was performed at the Medical University of South Carolina, Charleston, South Carolina, USA, between June 2007 and October 2008. MATERIALS: TNF-α transgenic rats (Xenogen Biosciences in Cranbury, New Jersey, USA) were utilized in this study. METHODS: TNF-α transgenic (tg) and wild-type (WT) rats underwent a complete single-level laminectomy at the 10^th thoracic vertebra (T10). MAIN OUTCOME MEASURES: Motor function of rat hindlimb was assessed using the Basso, Beattie, and Bresnahan hindlimb locomotor rating scale. Histological evaluation of spinal cord tissue loss was conducted. Immunohistochemistry for astrocytes, microglia/macrophages, and TNF receptors (TNFRs) was performed on spinal cord tissue sections. TNF-α mRNA expression was detected by real-time polymerase chain reaction. The concentrations of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in the supernatant were determined using an enzyme-linked immunosorbent assay kit for rat NGF or BDNF, respectively. The rats were injected subcutaneously with etanercept to verify that TNF-α was the direct effect of the modulation of behavioral and neurodegenerative outcomes in the TNF-α tg rats. RESULTS: TNF-α tg rats showed higher expression of TNF-α mRNA in the spinal cord prior to SCI. TNF-α tg rats showed worse motor deficits than WT rats in the acute period (〈 3 days) after SCI (P 〈 0.01), while in the chronic period, TNF-α tg rats exhibited persistent elevated baseline levels of TNF-α mRNA and improved recovery in motor function and tissue healing compared to WT rats (P 〈 0.01 ). Following SCI, the number of microglia/macrophages in TNF-α tg rat was always greater than in WT rat (P 〈 0.01). There were no significant differences in NGF and BDNF levels in the supernatant of spinal cord homogenates. TNFR1 expression was significantly greater in the TNF-α tg rats compared to the WT rats (P 〈 0.01). However, TNFR2 expression did not reveal a significant increase in the TNF-α tg rats compared to the WT rats. Finally, treatment with etanercept reduced injury acutely, but exacerbated the injury chronically. CONCLUSION: Overexpression of TNF-α is deleterious in the acute phase, but beneficial in the chronic phase in the response to SCI. The role of TNF-α post-injury may depend on TNF-α expression in the spinal cord and its differential binding to TNFRI. Our observations may have clinical relevance that antagonists or inhibitors of TNF-α could be administered within the early time window post-injury, and appropriate amounts of TNF-α could be administered during the chronic stage, in order to improve the final neurological recovery in patients with SCI.
基金supported by grants from the Heart and Stroke Foundation of Canada(HHC,AFRS)the Canadian Institutes of Health Research(to HHC and AFRS)supported by a Mid-Career Investigator Award from the Heart and Stroke Foundation of Ontario
文摘Ischemic brain injury triggers neuronal cell death by apoptosis via caspase activation and by necroptosis through activation of the receptor-interacting protein kinases (RIPK) associated with the tumor necrosis factor-alpha (TNF-a)/death receptor. Recent evidence shows RIPK inhibitors are neuroprotective and al- leviate ischemic brain injury in a number of animal models, however, most have not yet undergone clinical trials and safety in humans remains in question. Dabrafenib, originally identified as a B-raf inhibitor that is currently used to treat melanoma, was later revealed to be a potent RIPK3 inhibitor at micromolar con- centrations. Here, we investigated whether Dabrafenib would show a similar neuroprotective effect in mice subjected to ischemic brain injury by photothrombosis. Dabrafenib administered intraperitoneally at 10 mg/ kg one hour after photothrombosis-induced focal ischemic injury significantly reduced infarct lesion size in C57BL6 mice the following day, accompanied by a markedly attenuated upregulation of TNF-u. However, subsequent lower doses (5 mg/kg/day) failed to sustain this neuroprotective effect after 4 days. Dabrafenib bl ocked lipopolysaccharides-induced activation of TNF-ct in bone marrow-derived macrophages, suggesting that Dabrafenib may attenuate TNF-ct-induced necroptotic pathway after ischemic brain injury. Since Dab- rafenib is already in clinical use for the treatment of melanoma, it might be repurposed for stroke therapy.
基金supported by the Chinese Traditional Medical Science Foundation of Zhejiang Province in China,No.2010ZA072the Health Bureau Foundation of Zhejiang Province in China,No.2012ZDA023the Qianjiang Project of Zhejiang Science and Technology Bureau in China,No.2010 R10073
文摘Puerarin, a traditional Chinese medicine, exerts a powerful neuroprotective effect in cerebral ischemia/reperfusion injury, but its mechanism is unknown. Here, we established rat models of middle cerebral artery ischemia/reperfusion injury using the suture method. Puerarin (100 mg/kg) was administered intraperitoneally 30 minutes before middle cerebral artery occlusion and 8 hours after reperfusion. Twenty-four hours after reperfusion, we found that puerarin significantly improved neurological deficit, reduced infarct size and brain water content, and notably diminished the expression of Toll-like receptor-4, myeloid differentiation factor 88, nuclear factor kappa B and tumor necrosis factor-α in the ischemic region. These data indicate that puerarin exerts an anti-inflammatory protective effect on brain tissue with ischemia/reperfusion damage by downregulating the expression of multiple inflammatory factors.
文摘Previous studies have shown that vagus nerve stimulation can improve the prognosis of trau- matic brain injury. The aim of this study was to elucidate the mechanism of the neuroprotective effects of vagus nerve stimulation in rabbits with brain explosive injury. Rabbits with brain ex- plosive injury received continuous stimulation (10 V, 5 Hz, 5 ms, 20 minutes) of the right cervical vagus nerve. Tumor necrosis factor-a, interleukin-l~ and interleukin-10 concentrations were detected in serum and brain tissues, and water content in brain tissues was measured. Results showed that vagus nerve stimulation could reduce the degree of brain edema, decrease tumor necrosis factor-a and interleukin-1β concentrations, and increase interleukin-10 concentration after brain explosive injury in rabbits. These data suggest that vagus nerve stimulation may exert neuroprotective effects against explosive injury via regulating the expression of tumor necrosis factor-a, interleukin-1 β and interleukin-10 in the serum and brain tissue.
基金the Program of Kyung Hee University for Young Researchers in Medical Science,No.KHU-20081253
文摘Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Berberine, the effective ingredient of Coptidis Rhizoma and Cortex Phellodendti, has a wide range of pharmacological functions, including anti-inflammatory, anti-atherosclerotic and anti-cancer effects. The neuroprotective potential of berberine has previously been demonstrated. The present study aimed to examine whether berberine could repress microglial activation and can be considered a potential therapeutic candidate to target neurodegenerative diseases. Primary microglial cells and BV2 microglial cells were cultured and stimulated with bacterial lipopolysaccharide (LPS). Berberine chloride was treated prior to LPS or simultaneously with LPS stimulation. Results revealed that berberine was effective at inhibiting nitric oxide release from primary microglial cells when cells were exposed to the compound prior to LPS or simultaneously with LPS. It also reduced the LPS-stimulated production of tumor necrosis factor-α, interleukin-1β, prostaglandin E2, and intracellular reactive oxygen species and nuclear factor-kappa activation. Additionally, berberine reduced nitric oxide release from microglia stimulated with interferon-γ and amyloid β. These results suggest that berberine provides neuroprotection by reducing the production of various neurotoxic molecules from activated microglia.
基金Supported by: the Scientific Technology Research and Development Plan of Hebei Province, No. 06276103Dthe Natural Science Foundation of Hebei Province, No. C2006000915
文摘BACKGROUND: Certain components of tetramethylpyrazine, a traditional Chinese medicine, exhibit protective effects against brain injury. OBJECTIVE: To investigate the effects of different Naoxintong doses on expression of nuclear factor-kappa B ( kB), interleukin-6, tumor necrosis factor-α, and complement 3 in rats following focal cerebral ischemia. DESIGN, TIME AND SETTING: The randomized experiment was performed at the Laboratory of Neurology, Second Hospital of Hebei Medical University from June 2004 to June 2006. MATERIALS: A total of 150 adult, healthy, male, Sprague Dawley rats, weighing 280-320g, were selected. Naoxintong powder (mainly comprising szechwan lovage rhizome, milkvetch root, danshen root, and radix angelicae sinensis) was obtained from Buchang Pharmacy Co., Ltd. in Xianyang City of Shanxi Province of China, lot number 040608. METHODS: The rats were randomly assigned into sham operation, saline, high-dose Naoxintong, moderate-dose Naoxintong, and low-dose Naoxintong groups, with 30 rats in each group. Rat models of middle cerebral artery occlusion were established using the suture method, with the exception of the sham operation group. Rats in the high-dose, moderate-dose and low-dose Naoxintong groups received 4, 2, and 1 g/kg Naoxintong respectively, by gavage. Rats in the saline group were treated with 1 mL saline by gavage All rats were administered by gavage at 5 and 23 hours following surgery, and subsequently, once per day. MAIN OUTCOME MEASURES: At 6, 24, 48, 72 hours, and 7 days following model establishment, brain water content was measured. Histopathological changes in brain tissues were detected using hematoxylin-eosin staining. Expression of nuclear factor- kB, interleukin-6, tumor necrosis factor- α, and complement 3 was examined by immunohistochemistry. RESULTS: A total of 150 rats were included in the final analysis with no loss. Brain water content was significantly increased in the ischemic hemisphere of rats from the saline, as well as the high-dose, moderate-dose, and low-dose Naoxintong groups at 24 hours, which reached a peak at 48 hours. At 6, 24, 48, 72 hours, and 7 days, brain water content was greater in the ischemic hemisphere of rats from the saline, as well as the high-dose, moderate-dose, and low-dose Naoxintong groups, compared with the sham operation group (P 〈 0.05). At 24 and 48 hours, brain water content was reduced in the high-dose and moderate-dose Naoxintong groups, compared to the saline and low-dose Naoxintong groups (P 〈 0.05). In the saline, as well as high-dose, moderate-dose, and low-dose Naoxintong groups, neuronal edema was observed at 6 hours surrounding the ischemic sites. Inflammatory cells appeared at 24 hours, reached a peak at 48 hours, and gradually diminished. A small amount of glial cell proliferation and neuronal degeneration were observed in the hippocampus at 72 hours following infarction. Microglial proliferation and aggregation were detected at 7 days after infarction. Expression of nuclear factor- kB, interleukin-6, tumor necrosis factor-α, and complement 3 was significantly less in the high-dose, moderate-dose, and low-dose Naoxintong groups, compared to the sham operation group (P 〈 0.05). Expression of the above-mentioned inflammatory cytokines was lower in rat brain tissues of the high-dose Naoxintong group, compared to the low-dose Naoxintong group (P 〈 0.05). CONCLUSION: High-dose Naoxintong and moderate-dose Naoxintong significantly alleviated rat brain edema and decreased expression of nuclear factor-kB, interleukin-6, tumor necrosis factor-α, and complement 3 in brain tissues. The protective effect of high-dose Naoxintong was most significant.