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1.
In many neurodegenerative diseases and particularly in Parkinson’s disease, deficits in olfaction are reported to occur early in the disease process and may be a useful behavioral marker for early detection. Earlier detection in neurodegenerative disease is a major goal in the field because this is when neuroprotective therapies have the best potential to be effective. Therefore, in preclinical studies testing novel neuroprotective strategies in rodent models of neurodegenerative disease, olfactory assessment could be highly useful in determining therapeutic potential of compounds and translation to the clinic. In the present study we describe a battery of olfactory assays that are useful in measuring olfactory function in mice. The tests presented in this study were chosen because they measure olfaction abilities in mice related to food odors, social odors, and non-social odors. These tests have proven useful in characterizing novel genetic mouse models of Parkinson’s disease as well as in testing potential disease-modifying therapies.  相似文献   

2.
The development of effective neuroprotective therapies for Parkinson''s disease (PD) has been severely hindered by the notable lack of an appropriate animal model for preclinical screening. Indeed, most models currently available are either acute in nature or fail to recapitulate all characteristic features of the disease. Here, we present a novel progressive model of PD, with behavioural and cellular features that closely approximate those observed in patients. Chronic exposure to dietary phytosterol glucosides has been found to be neurotoxic. When fed to rats, β-sitosterol β-d-glucoside (BSSG) triggers the progressive development of parkinsonism, with clinical signs and histopathology beginning to appear following cessation of exposure to the neurotoxic insult and continuing to develop over several months. Here, we characterize the progressive nature of this model, its non-motor features, the anatomical spread of synucleinopathy, and response to levodopa administration. In Sprague Dawley rats, chronic BSSG feeding for 4 months triggered the progressive development of a parkinsonian phenotype and pathological events that evolved slowly over time, with neuronal loss beginning only after toxin exposure was terminated. At approximately 3 months following initiation of BSSG exposure, animals displayed the early emergence of an olfactory deficit, in the absence of significant dopaminergic nigral cell loss or locomotor deficits. Locomotor deficits developed gradually over time, initially appearing as locomotor asymmetry and developing into akinesia/bradykinesia, which was reversed by levodopa treatment. Late-stage cognitive impairment was observed in the form of spatial working memory deficits, as assessed by the radial arm maze. In addition to the progressive loss of TH+ cells in the substantia nigra, the appearance of proteinase K-resistant intracellular α-synuclein aggregates was also observed to develop progressively, appearing first in the olfactory bulb, then the striatum, the substantia nigra and, finally, hippocampal and cortical regions. The slowly progressive nature of this model, together with its construct, face and predictive validity, make it ideal for the screening of potential neuroprotective therapies for the treatment of PD.  相似文献   

3.

Acute inhalation of combustion smoke produces long-term neurologic deficits in survivors. To study the mechanisms that contribute to the development of neurologic deficits and identify targets for prevention, we developed a mouse model of acute inhalation of combustion smoke, which supports longitudinal investigation of mechanisms that underlie the smoke induced inimical sequelae in the brain. Using a transgenic mouse engineered to overexpress neuroglobin, a neuroprotective oxygen-binding globin protein, we previously demonstrated that elevated neuroglobin preserves mitochondrial respiration and attenuates formation of oxidative DNA damage in the mouse brain after smoke exposure. In the current study, we show that elevated neuronal neuroglobin attenuates the persistent inflammatory changes induced by smoke exposure in the mouse brain and mitigates concordant smoke-induced long-term neurobehavioral deficits. Specifically, we found that increases in hippocampal density of GFAP and Iba-1 positive cells that are detected post-smoke in wild-type mice are absent in the neuroglobin overexpressing transgenic (Ngb-tg) mice. Similarly, the smoke induced hippocampal myelin depletion is not observed in the Ngb-tg mice. Importantly, elevated neuroglobin alleviates behavioral and memory deficits that develop after acute smoke inhalation in the wild-type mice. Taken together, our findings suggest that the protective effects exerted by neuroglobin in the brains of smoke exposed mice afford protection from long-term neurologic sequelae of acute inhalation of combustion smoke. Our transgenic mouse provides a tool for assessing the potential of elevated neuroglobin as possible strategy for management of smoke inhalation injury.

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4.
Vanillin (4-hydroxy-3-methoxybenzaldehyde), a pleasant smelling organic aromatic compound, is widely used as a flavoring additive in food, beverage, cosmetic and drug industries. It is reported to cross the blood brain barrier and also displayed antioxidant and neuroprotective activities. We previously reported the neuroprotective effect of vanillin against rotenone induced in in vitro model of PD. The present experiment was aimed to analyze the neuroprotective effect of vanillin on the motor and non-motor deficits, neurochemical variables, oxidative, anti-oxidative indices and the expression of apoptotic markers against rotenone induced rat model of Parkinson’s disease (PD). Rotenone treatment exhibited motor and non-motor impairments, neurochemical deficits, oxidative stress and apoptosis, whereas oral administration of vanillin attenuated the above-said indices. However further studies are needed to explore the mitochondrial protective and anti-inflammatory properties of vanillin, as these processes play a vital role in the cause and progression of PD.  相似文献   

5.
Possible strategies for treating ischemic stroke include: (1) Neuroprotection: preventing damaged neurons from undergoing apoptosis in the acute phase of cerebral ischemia; (2) Stem cell therapy: the repair of broken neuronal networks with newly born neurons in the chronic phase of cerebral ischemia. Firstly, we studied the neuroprotective effect of a calcium channel blocker, azelnidipine, or a by-product of heme degradation, biliverdin, in the ischemic brain. These results revealed both azelnidipine and biliverdin had a neuroprotective effect in the ischemic brain through their anti-oxidative property. Secondly, we investigated the role of granulocyte colony-stimulating factor (G-CSF) by administering G-CSF to rats after cerebral ischemia and found G-CSF plays a critical role in neuroprotection. Lastly, we developed a restorative stroke therapy with a bio-affinitive scaffold, which is able to provide an appropriate environment for newly born neurons. In the future, we will combine these strategies to develop more effective therapies for treatment of strokes. Special issue article in honor of Dr. Akitane Mori.  相似文献   

6.
Efforts to develop animal models for human immunodeficiency virus type-1 (HIV-1) vaccine testing have focused on lentivirus infection of nonhuman primates. A long-term goal of this primate research is to utilize the models to understand the mechanisms of pathogenesis leading to AIDS. Because the time to disease is compressed relative to HIV infection in humans, therapeutic strategies and compounds can be tested in nonhuman primate models in a shorter time frame and under more controlled conditions than are possible in many clinical studies. Recent interventive studies in primates using antiviral drugs or passive immune globulin (IgG) have demonstrated that multiple log reductions in plasma virus can be achieved and sustained, with accompanying health benefits. Information gained about timing and dosage may be of utility in designing clinical studies. The development of reliable and predictable animal models for effective therapies and vaccines against AIDS remains a critical priority for primate research.  相似文献   

7.
Oxidative stress is a common feature in neurodegenerative diseases associated with neuroinflammation, and therefore, has been proposed as a key target for novel therapies for these diseases. Recently, adipose-derived stem cell (ASC)-based cell therapy has emerged as a novel strategy for neuroprotection. In this study, we evaluate the therapeutic role of ASC-conditioned medium (ASC-CM) against H2O2-induced neurotoxicity in a new in vitro model of ec23/brain-derived neurotrophic factor (BDNF)-differentiated human SH-SY5Y neuron-like cells (SH-SY5Yd). In the presence of ASC-CM, stressed SH-SY5Yd cells recover normal axonal morphology (with an almost complete absence of H2O2-induced axonal beading), electrophysiological features, and cell viability. This beneficial effect of ASC-CM was associated with its antioxidant capacity and the presence of growth factors, namely, BDNF, glial cell line-derived neurotrophic factor, and transforming growth factor β1. Moreover, the neuroprotective effect of ASC-CM was very similar to that obtained from treatment with BDNF, an essential factor for SH-SY5Yd cell survival. Importantly, we also found that the addition of the antioxidant agent N-acetyl cysteine to ASC-CM abolished its restorative effect; this was associated with a strong reduction in reactive oxygen species (ROS), in contrast to the moderate decrease in ROS produced by ASC-CM alone. These results suggest that neuronal restorative effect of ASC-CM is associated with not only the release of essential neurotrophic factors, but also the maintenance of an appropriate redox state to preserve neuronal function.  相似文献   

8.
Pinna A  Wardas J  Simola N  Morelli M 《Life sciences》2005,77(26):3259-3267
The development of non-dopaminergic therapies for the treatment of Parkinson's disease (PD) has attracted much interest in recent years. Among new different classes of drugs, adenosine A2A receptor antagonists have emerged as best candidates. The present review will provide an updated summary of the results reported in literature concerning the effects of adenosine A2A antagonists in rodent and primate models of PD. These results show that A2A receptor antagonists improve motor deficits without inducing dyskinesia and counteract parkinsonian tremor. In progress clinical trials have shown that a low dose of L-DOPA plus KW-6002 produced symptomatic relief no different from that produced by an optimal dose of L-DOPA alone, whereas dyskinesias were reduced rendering this class of compounds particularly attractive.  相似文献   

9.
Abnormalities in mitochondrial function and epigenetic regulation are thought to be instrumental in Huntington's disease (HD), a fatal genetic disorder caused by an expanded polyglutamine track in the protein huntingtin. Given the lack of effective therapies for HD, we sought to assess the neuroprotective properties of the mitochondrial energizing ketone body, D-β-hydroxybutyrate (DβHB), in the 3-nitropropionic acid (3-NP) toxic and the R6/2 genetic model of HD. In mice treated with 3-NP, a complex II inhibitor, infusion of DβHB attenuates motor deficits, striatal lesions, and microgliosis in this model of toxin induced-striatal neurodegeneration. In transgenic R6/2 mice, infusion of DβHB extends life span, attenuates motor deficits, and prevents striatal histone deacetylation. In PC12 cells with inducible expression of mutant huntingtin protein, we further demonstrate that DβHB prevents histone deacetylation via a mechanism independent of its mitochondrial effects and independent of histone deacetylase inhibition. These pre-clinical findings suggest that by simultaneously targeting the mitochondrial and the epigenetic abnormalities associated with mutant huntingtin, DβHB may be a valuable therapeutic agent for HD.  相似文献   

10.
Computational, systems-based approaches can provide a quantitative construct for evaluating risk in the context of mechanistic data. Previously, we developed computational models for the rat, mouse, rhesus monkey, and human, describing the acquisition of adult neuron number in the neocortex during the key neurodevelopmental processes of neurogenesis and synaptogenesis. Here we apply mechanistic data from the rat describing ethanol-induced toxicity in the developing neocortex to evaluate the utility of these models for analyzing neurodevelopmental toxicity across species. Our model can explain long-term neocortical neuronal loss in the rodent model after in utero exposure to ethanol based on inhibition of proliferation during neurogenesis. Our human model predicts a significant neuronal deficit after daily peak BECs reaching 10-20 mg/dl, which is the approximate BEC reached after drinking one standard drink within one hour. In contrast, peak daily BECs of 100 mg/dl are necessary to predict similar deficits in the rat. Our model prediction of increased sensitivity of primate species to ethanol-induced inhibition of proliferation is based on application of in vivo experimental data from primates showing a prolonged rapid growth period in the primate versus rodent neuronal progenitor population. To place our predictions into a broader context, we evaluate the evidence for functional low-dose effects across rats, monkeys, and humans. Results from this critical evaluation suggest subtle effects are evident at doses causing peak BECs of approximately 20 mg/dl daily, corroborating our model predictions. Our example highlights the utility of a systems-based modeling approach in risk assessment.  相似文献   

11.
Nonhuman primate models of Parkinson's disease   总被引:3,自引:0,他引:3  
Nonhuman primate (NHP) models of Parkinson's disease (PD) play an essential role in the understanding of PD pathophysiology and the assessment of PD therapies. NHP research enabled the identification of environmental risk factors for the development of PD. Electrophysiological studies in NHP models of PD identified the neural circuit responsible for PD motor symptoms, and this knowledge led to the development of subthalamic surgical ablation and deep brain stimulation. Similar to human PD patients, parkinsonian monkeys are responsive to dopamine replacement therapies and present complications associated with their long-term use, a similarity that facilitated the assessment of new symptomatic treatments, such as dopaminergic agonists. New generations of compounds and novel therapies that use directed intracerebral delivery of drugs, cells, and viral vectors benefit from preclinical evaluation in NHP models of PD. There are several NHP models of PD, each with characteristics that make it suitable for the study of different aspects of the disease or potential new therapies. Investigators who use the models and peer scientists who evaluate their use need information about the strengths and limitations of the different PD models and their methods of evaluation. This article provides a critical review of available PD monkey models, their utilization, and how they compare to emerging views of PD as a multietiologic, multisystemic disease. The various models are particularly useful for representing different aspects of PD at selected time points. This conceptualization provides clues for the development of new NHP models and facilitates the clinical translation of findings. As ever, successful application of any model depends on matching the model to the scientific question to be answered. Adequate experimental designs, with multiple outcome measures of clinical relevance and an appropriate number of animals, are essential to minimize the limitations of models and increase their predictive clinical validity.  相似文献   

12.
HIV and antiretroviral therapy in the brain: neuronal injury and repair   总被引:4,自引:0,他引:4  
Approximately 40 million people worldwide are infected with human immunodeficiency virus (HIV). Despite HIV's known propensity to infect the CNS and cause neurological disease, HIV neurocognitive disorders remain under-recognized. Although combination antiretroviral therapy has improved the health of millions of those living with HIV, the penetration into the CNS of many such therapies is limited, and patients' quality of life continues to be diminished by milder, residual neurocognitive impairment. Synaptodendritic neuronal injury is emerging as an important mediator of such deficits in HIV. By carefully selecting specific antiretrovirals and supplementing them with neuroprotective agents, physicians might be able to facilitate innate CNS repair, promoting enhanced synaptodendritic plasticity, neural function and clinical neurological status.  相似文献   

13.
Oligodendrocyte progenitor cells (OPCs) are the focus of intense research for the purpose of cell replacement therapies in acquired or inherited neurodegenerative disorders, accompanied by ongoing hypo/demyelination. Recently, it has been postulated that these glia-committed cells exhibit certain properties of neural stem cells. Advances in stem cell biology have shown that their therapeutic effect could be attributed to their ability to secret numerous active compounds which modify the local microenvironment making it more susceptible to restorative processes. To verify this hypothesis, we set up an ex vivo co-culture system of OPCs isolated from neonatal rat brain with organotypic hippocampal slices (OHC) injured by oxygen-glucose deprivation (OGD). The presence of OPCs in such co-cultures resulted in a significant neuroprotective effect manifesting itself as a decrease in cell death rate and as an extension of newly formed cells in ischemically impaired hippocampal slices. A microarray analysis of broad spectrum of trophic factors and cytokines expressed by OPCs was performed for the purpose of finding the factor(s) contributing to the observed effect. Three of them—BDNF, IL-10 and SCF—were selected for the subsequent functional assays. Our data revealed that BDNF released by OPCs is the potent factor that stimulates cell proliferation and survival in OHC subjected to OGD injury. At the same time, it was observed that IL-10 attenuates inflammatory processes by promoting the formation of the cells associated with the immunological response. Those neuroprotective qualities of oligodendroglia-biased progenitors significantly contribute to anticipating a successful cell replacement therapy.  相似文献   

14.
Ischemic stroke, although causing brain infarction and neurological deficits, can activate innate neuroprotective mechanisms, including regional mechanisms within the ischemic brain and distant mechanisms from non-ischemic organs such as the liver, spleen, and pancreas, supporting neuronal survival, confining brain infarction, and alleviating neurological deficits. Both regional and distant mechanisms are defined as systems neuroprotective mechanisms. The regional neuroprotective mechanisms involve release and activation of neuroprotective factors such as adenosine and bradykinin, inflammatory responses, expression of growth factors such as nerve growth factors and neurotrophins, and activation and differentiation of resident neural stem cells to neurons and glial cells. The distant neuroprotective mechanisms are implemented by expression and release of endocrine neuroprotective factors such as fibroblast growth factor 21, resistin like molecule γ, and trefoil factor 3 from the liver; brain-derived neurotrophic factor and nerve growth factor from the spleen; and neurotrophin 3 and vascular endothelial growth factor C from the pancreas. Furthermore, ischemic stroke induces mobilization of bone marrow hematopoietic stem cells and endothelial progenitor cells into the circulatory system and brain, contributing to neuroprotection. The regional and distant mechanisms may act in coordination and synergy to protect the ischemic brain from injury and death. This paper addresses these mechanisms and associated signaling networks.  相似文献   

15.

Background & Aims

The therapeutic benefits of mesenchymal stem cells (MSCs), such as homing ability, multipotent differentiation capacity and secretion of soluble bioactive factors which exert neuroprotective, anti-inflammatory and immunomodulatory properties, have been attributed to attenuation of autoimmune, inflammatory and neurodegenerative disorders. In this study, we aimed to determine the earliest time point at which locally administered MSC-based therapies avert enteric neuronal loss and damage associated with intestinal inflammation in the guinea-pig model of colitis.

Methods

At 3 hours after induction of colitis by 2,4,6-trinitrobenzene-sulfonate (TNBS), guinea-pigs received either human bone marrow-derived MSCs, conditioned medium (CM), or unconditioned medium by enema into the colon. Colon tissues were collected 6, 24 and 72 hours after administration of TNBS. Effects on body weight, gross morphological damage, immune cell infiltration and myenteric neurons were evaluated. RT-PCR, flow cytometry and antibody array kit were used to identify neurotrophic and neuroprotective factors released by MSCs.

Results

MSC and CM treatments prevented body weight loss, reduced infiltration of leukocytes into the colon wall and the myenteric plexus, facilitated repair of damaged tissue and nerve fibers, averted myenteric neuronal loss, as well as changes in neuronal subpopulations. The neuroprotective effects of MSC and CM treatments were observed as early as 24 hours after induction of inflammation even though the inflammatory reaction at the level of the myenteric ganglia had not completely subsided. Substantial number of neurotrophic and neuroprotective factors released by MSCs was identified in their secretome.

Conclusion

MSC-based therapies applied at the acute stages of TNBS-induced colitis start exerting their neuroprotective effects towards enteric neurons by 24 hours post treatment. The neuroprotective efficacy of MSC-based therapies can be exerted independently to their anti-inflammatory effects.  相似文献   

16.

Background  

The major difficulty in postoperative care in patients after craniotomy is to distinguish the intracranial deficits from the residual effect of general anesthesia. In present study, we used cerebral state index (CSI) monitoring in patients after craniotomy with delayed recovery, and evaluated the prediction probability of CSI for long-term postoperative unconsciousness.  相似文献   

17.
In previous work, we have shown that perinatal asphyxia (PA) in the rat leads to life-long neurotransmitter deficits and impairment of cognitive functions and behavior. This observation made us examine protein expression in hippocampus of rats with PA at the end of the life span. We applied a well-documented and characterized animal model of PA. Pups, normoxic and asphyxiated for 20 min, were brought up until the age of 24 months and then were sacrificed. Hippocampal tissue was dissected from the brains, and proteins were run on two-dimensional gel electrophoresis with in-gel digestion and subsequent identification of proteins by MALDI-TOF followed by quantification of protein spots by specific software. In hippocampus of rats with PA, the stress proteins protein disulfide isomerase A3 precursor and stress-induced phosphoprotein-1 were significantly increased, whereas the microtubule-associated protein dynamin-1 was significantly reduced. Increased stress protein levels may represent long-term effects of PA or, alternatively, could reflect conditioning of the stress protein machinery known to occur as a neuroprotective principle following hypoxic-ischemic conditions. Decreased dynamin-1 levels may be considered as a long-term effect on the exocytotic system possibly reflecting or leading to impaired neuronal transport and vesicle-trafficking in PA of the rat of advanced age.  相似文献   

18.
β-Amyloid (Aβ) is the main component of amyloid plaques developed in the brain of patients with Alzheimer's disease (AD). The increasing burden of Aβ in the cortex and hippocampus is closely correlated with memory loss and cognition deficits in AD. Recently, leptin, a 16 kD peptide derived mainly from white adipocyte tissue, has been appreciated for its neuroprotective function, although less is known about the effects of leptin on spatial memory and synaptic plasticity. The present study investigated the neuroprotective effects of leptin against Aβ-induced deficits in spatial memory and in vivo hippocampal late-phase long-term potentiation (L-LTP) in rats. Y maze spontaneous alternation was used to assess short term working memory, and the Morris water maze task was used to assess long term reference memory. Hippocampal field potential recordings were performed to observe changes in L-LTP. We found that chronically intracerebroventricular injection of leptin (1 μg) effectively alleviated Aβ1–42 (20 μg)-induced spatial memory impairments of Y maze spontaneous alternation and Morris water maze. In addition, chronic administration of leptin also reversed Aβ1–42-induced suppression of in vivo hippocampal L-LTP in rats. Together, these results suggest that chronic leptin treatments reversed Aβ-induced deficits in learning and memory and the maintenance of L-LTP.  相似文献   

19.
Despite advances in neonatal care, hypoxic-ischemic brain injury is still a serious clinical problem, which is responsible for many cases of perinatal mortality, cerebral palsy, motor impairment and cognitive deficits. Resveratrol, a natural polyphenol with important anti-oxidant and anti-inflammatory properties, is present in grapevines, peanuts and pomegranates. The aim of the present work was to evaluate the possible neuroprotective effect of resveratrol when administered before or immediately after a hypoxic-ischemic brain event in neonatal rats by analyzing brain damage, the mitochondrial status and long-term cognitive impairment. Our results indicate that pretreatment with resveratrol protects against brain damage, reducing infarct volume, preserving myelination and minimizing the astroglial reactive response. Moreover its neuroprotective effect was found to be long lasting, as behavioral outcomes were significantly improved at adulthood. We speculate that one of the mechanisms for this neuroprotection may be related to the maintenance of the mitochondrial inner membrane integrity and potential, and to the reduction of reactive oxygen species. Curiously, none of these protective features was observed when resveratrol was administered immediately after hypoxia-ischemia.  相似文献   

20.
Intracerebral hemorrhage (ICH) is a severe form of brain injury, which is a major cause of mortality in humans. Hydrocephalus and cerebral hematoma lead to severe neurological deficits. A single autologous blood (ALB) injection in rats' brains induces hemorrhage and other conditions that regularly interfere with the standard treatment of several cellular and molecular pathways. Several studies have found that IGF-1/GLP-1 decreases the production of inflammatory markers in peripheral tissues, while some have found that they also have pro-inflammatory functions. Since these receptors are down-regulated in hemorrhagic situations, we looked into the potential neuroprotective effect of 4-hydroxyisoleucine (4-HI); 50 mg/kg and 100 mg/kg, an active compound Trigonellafoenum-graecum, on post-hemorrhagic deficits in rats. Long-term oral administration of 4-HI for 35 days has improved behavioral and neurochemical deficits and severe pathological changes and improved cellular and molecular markers, apoptotic markers in the ALB-induced ICH experimental model.Furthermore, the findings revealed that 4-HI also improved the levels of other neurotransmitters (Ach, DOPA, GABA, glutamate); inflammatory cytokines (TNF-alpha, IL-1β, IL-17), and oxidative stress markers (MDA, nitrite, LDH, AchE, SOD, CAT, GPx, GSH) in the brain when evaluated after Day 35. There is no proven treatment available for the prevention of post-brain hemorrhage and neurochemical malfunction; available therapy is only for symptomatic relief of the patient. Thus, 4-HI could be a potential clinical approach for treating post-brain haemorrhage and neurochemical changes caused by neurological damage. Furthermore, 4-HI may be linked to other standard therapeutic therapies utilized in ICH as a potential pharmacological intervention.  相似文献   

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