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1.
慢性牙周炎属于慢性感染性疾病,与多种全身疾病存在双向关系。帕金森病是一种常见的神经退行性变性疾病,炎症反应在其进展中起到一定作用。近年来,大量研究提示慢性牙周炎与帕金森病等神经退行性变性疾病之间存在潜在联系,帕金森病患者牙周状况较差,其口腔菌群组成与健康人群存在差异;与此同时,慢性牙周炎患者罹患帕金森病的风险更高,定期牙周治疗可能在一定程度上降低该风险。慢性牙周炎与帕金森病的相互作用机制尚未明确,部分研究认为帕金森病患者可能由于运动及非运动症状,无法有效维护口腔卫生,增加牙周炎患病风险;小胶质细胞介导的神经炎症则可能是慢性牙周炎影响帕金森病的关键,牙周致病菌及炎症介质或可通过多种途径进入大脑并激活小胶质细胞,最终影响帕金森病的发生发展。本文就慢性牙周炎与帕金森病相关性及可能的交互作用机制的最新研究进展作一综述,以期为进一步探讨两者相互影响的研究提供思路。  相似文献   
2.
Objectives: Increases in astrocytes and one of their markers, glial fibrillary acidic protein (GFAP) have been reported in the brains of patients with Alzheimer’s disease (AD). N-3 polyunsaturated fatty acids (PUFA) modulate neuroinflammation in animal models; however, their effect on astrocytes is unclear.

Methods: Fat-1 mice and their wildtype littermates were fed either a fish oil diet or a safflower oil diet deprived of n-3 PUFA. At 12 weeks, mice underwent intracerebroventricular infusion of amyloid-β 1-40. Astrocyte phenotype in the hippocampus was assessed at baseline and 10 days post-surgery using immunohistochemistry with various microscopy and image analysis techniques.

Results: GFAP increased in all groups in response to amyloid-β, with a greater increase in fish oil-fed mice than either fat-1 or wildtype safflower oil-fed mice. Astrocytes in this group were also more hypertrophic, suggesting increased activation. Both fat-1- and fish oil-fed mice had greater increases in branch number and length in response to amyloid-β infusion than wildtype safflower animals.

Conclusion: Fish oil feeding, and to a lesser extent the fat-1 transgene, enhances the astrocyte activation phenotype in response to amyloid-β 1-40. Astrocytes in mice fed fish oil were more activated in response to amyloid-β than in fat-1 mice despite similar levels of hippocampal n-3 PUFA, which suggests that other fatty acids or dietary factors contribute to this effect.  相似文献   

3.
Parkinson's disease (PD) is characterized by the degeneration of dopaminergic (DA) neurons constituting the nigrostriatal pathway. Neuroinflammation, related to microglial activation, plays an important role in this process. Exploration of animal models of PD using neuroimaging modalities allows to better understand the pathophysiology of the disease. Here, we fully explored a moderate lesion model in the rat in which 6‐hydroxydopamine was unilaterally delivered in three sites along the striatum. The degenerative process was assessed through in vivo Positron Emission Tomography (PET) imaging and in vitro autoradiographic quantitation of the striatal dopamine transporter (DAT) and immunostaining of tyrosine hydroxylase (TH). The microglial activation was studied through in vitro autoradiographic quantitation of the 18 kDa translocator protein (TSPO) in the striatum and CD11b staining in the SN. In addition, a targeted metabolomics exploration was performed in both these structures using mass spectrometry coupled to HPLC. Our results showed a reproducible decrease in the striatal DAT density associated with a reduction in the number of TH‐positive cells in the SN and striatum, reflecting a robust moderate degeneration of nigrostriatal DA neurons. In addition, we observed strong microglia activation in both the striatum and SN ipsilateral to the lesion, highlighting that this moderate degeneration of DA neurons was associated with a marked neuroinflammation. Our metabolomics studies revealed alterations of specific metabolites and metabolic pathways such as carnitine, arginine/proline, and histidine metabolisms. These results bring new insights in the PD mechanism knowledge and new potential targets for future therapeutic strategies.  相似文献   
4.
In the past decade, numerous studies have demonstrated the close relationship between gut microbiota and the occurrence and development of Alzheimer’s disease (AD). However, the specific mechanism is still unclear. Both the neuroinflammation and systemic inflammation serve as the key hubs to accelerate the process of AD by promoting pathology and damaging neuron. What's more, the gut microbiota is also crucial for the regulation of inflammation. Therefore, this review focused on the role of gut microbiota in AD through inflammatory pathways. Firstly, this review summarized the relationship and interaction among gut microbiota, inflammation, and AD. Secondly, the direct and indirect regulatory effects of gut microbiota on AD through inflammatory pathways were described. These effects were mainly mediated by the component of the gut microbiota (lipopolysaccharides (LPS) and amyloid peptides), the metabolites of bacteria (short-chain fatty acids, branched amino acids, and neurotransmitters) and functional by-products (bile acids). In addition, potential treatments (fecal microbiota transplantation, antibiotics, probiotics, prebiotics, and dietary interventions) for AD were also discussed through these mechanisms. Finally, according to the current research status, the key problems to be solved in the future studies were proposed.  相似文献   
5.
【摘要】 目的 研究髓样细胞 2触发受体(TREM2)是否参与成年小鼠手术诱发的围术期神经认知障碍(PND)。方法 将20只雄性野生型C57BL/6小鼠随机分为对照组和手术组各10只,在手术前24小时对小鼠进行恐惧条件训练,恐惧条件测试(FCT)分别在术后1、3和7天进行,并采用旷场实验评估小鼠的运动能力。在最后一次行为评估后,将动物处死进行Western blot检测TREM2的表达。将40只小鼠随机分为对照组、手术组、Hsp60+手术组和TREM2 siRNA+HSP60+手术组,每组各10只。手术前30分钟将TREM2 siRNA立体定向注射入侧脑室。选择性TREM2受体激动剂HSP60,在麻醉苏醒后立即腹腔注射5μg/小鼠,按前述方法每24小时注射一次,连续7天,在手术前24小时对小鼠进行恐惧条件训练,FCT分别分别在术后1、3和7天进行,并采用旷场实验评估小鼠的运动能力。在最后一次行为评估后,一半小鼠(n=5)用于Western blot和ELISA分析,另一半(n=5)用于免疫荧光检测。结果 在异氟烷麻醉下对成年C57BL/6小鼠行胫骨骨折髓内固定术,发现该手术不会损害小鼠的运动能力,但会恶化学习和记忆功能,并降低TREM2表达。通过使用选择性TREM2激动剂HSP60,发现TREM2在小鼠脑海马组织中的表达明显增加,从而改善了学习和记忆,并减轻了小鼠的神经炎症反应。TREM2 siRNA消除了HSP60诱导的TREM2表达的增加,并逆转了HSP60诱导的小鼠学习和记忆功能以及小鼠脑神经炎症水平的改善。结论 TREM2的上调可能与减轻神经炎症和改善学习记忆功能有关,并减少PND的发生。  相似文献   
6.
Sepsis-associated encephalopathy (SAE) increases not only morbidity and mortality but has been associated with long-lasting mental impairment after hospital discharge in septic patients. Recently, studies have shown that these mental impairments are caused by infection-induced neuroinflammation. However, the role of T cells in the pathogenesis of SAE and mental impairments remains unclear. Thus, in this study, we aimed to clarify how immune cells, especially T cells, influence the development and recovery of these disorders. In the cecal slurry (CS)-induced septic mouse model, we performed three different kinds of behavioral tests, open-field test, marble burying test, and forced swimming test, and observed anxiety-like behavior in septic mice. Additionally, increased interleukin (IL)-1β and IL-6 expression levels, and infiltration of neutrophils and T cells were examined in the brain of septic mice, 10 days after sepsis onset. Twenty days after sepsis onset, the septic mice could recover the number of astrocytes. At day 30, expression levels of IL-1β and tumor necrosis factor (TNF)-α returned to normal levels in the cerebral cortex of septic mice. Interestingly, resolution of neuroinflammation and alleviation of depression were delayed in septic mice treated with FTY720, which inhibits sphingosine-1-phosphate (S1P)-dependent lymphocyte egress from lymph nodes. On analyzing the brain T cells with or without FTY720 in septic mice, the FTY720 untreated mice presented increased regulatory T cells (Treg) and Th2 cells in the brain, whereas the FTY720 treated mice demonstrated increased Th17 in the brain at day 30. Furthermore, in FTY720 treated septic mice, the number of astrocytes in the cerebral cortex remained reduced at day 30. These results suggest that infiltrated Treg and Th2 cells contribute to the attenuation SAE and alleviate SAE-induce mental disorder by resolving neuroinflammation in the chronic phase of sepsis.  相似文献   
7.
CNS inflammation is a key factor in Alzheimer’s Disease (AD), but its relation to pathological Aβ, tau, and APOE4 is poorly understood, particularly prior to the onset of cognitive symptoms. To better characterize early relationships between inflammation, APOE4, and AD pathology, we assessed correlations between cerebrospinal fluid (CSF) inflammatory markers and brain levels of Aβ and tau in cognitively normal older adults.Each participant received a lumbar puncture to collect and quantify CSF levels of TNFα, IL-6, IL-8, and IL-10, a T1-weighted MRI, and PET scanning with [18F]flortaucipir (FTP; n = 57), which binds to tau tangles and/or [18F]florbetapir (FBP; n = 58), which binds to Aβ. Parallel voxelwise regressions assessed relationships between each CSF inflammatory marker and FTP and FBP SUVR, as well as APOE4*CSF inflammation interactions.Unexpectedly, we detected significant negative associations between regional Aβ and tau PET uptake and CSF inflammatory markers. For Aβ PET, we detected negative associations with CSF IL-6 and IL-8 in regions known to show early accumulation of Aβ (i.e. lateral and medial frontal lobes). For tau PET, negative relationships were observed with CSF TNFα and IL-8, predominantly in regions known to exhibit early tau accumulation (i.e. medial temporal lobe). In subsequent analyses, significant interactions between APOE4 status and IL-8 on Aβ and tau PET levels were observed in spatially distinct regions from those showing CSF–Aβ/tau relationships.Results from the current cross-sectional study support previous findings that neuroinflammation may be protective against AD pathology at a given stage of the disease, and extend these findings to a cognitively normal aging population. This study provides new insight into a dynamic relationship between neuroinflammation and AD pathology and may have implications for whom and when neuroinflammatory therapies may be appropriate.  相似文献   
8.
Emerging evidence indicates an important role for neuroinflammation in depression. Brief maternal separation promotes resilience to depression in offspring, but relatively little is known about the effects of different durations of postpartum separation (PS) from offspring on anxiety and depressive-like behaviors in dams following immune challenge. Lactating C57BL/6J mice were subjected to no separation (NPS), brief PS (15 min/day, PS15) or prolonged PS (180 min/day, PS180) from postpartum day (PPD) 1 to PPD21 and then injected with lipopolysaccharide (LPS). Behavioral tests, including the open field test (OFT) and forced swimming test (FST), were carried out at 24 h after the injection. LPS resulted in anxiety and depressive-like behaviors in NPS dams and activated ionized calcium-binding adaptor molecule (Iba1), an important biomarker of microglia, in the hippocampus. However, compared with NPS + LPS dams, PS15 + LPS dams spent significantly more time in the center of the OFT (anxiety-like behavior) and exhibited lower immobility time in the FST (depressive-like behavior), which indicated a phenomenon of resilience. Furthermore, the activation of neuroinflammation was inhibited in PS15 dams. Specifically, levels of the Iba1 mRNA and protein were decreased, while the mRNA expression of NLR family pyrin domain containing 3 (NLRP3) inflammasome/interleukin-18 (IL-18)/nuclear factor kappa-B (NF-κB) was decreased in the hippocampus. Furthermore, positive linear correlations were observed between microglial activation and LPS-induced depressive-like behaviors in dams. Collectively, the findings of this study confirm that brief PS from offspring promotes resilience to LPS immune challenge-induced behavioral deficits and inhibits neuroinflammation in dams separated from their offspring during lactation.  相似文献   
9.
目的研究白藜芦醇对蛛网膜下腔出血(subarachnoid hemorrhage,SAH)后血肿区脑组织神经炎症的作用和机制。方法将48只成年雄性SD大鼠随机分为三组:假手术组,SAH组和SAH+白藜芦醇处理组,每组16只。采用枕大池两次注血法构建SAH模型。SAH组和SAH+白藜芦醇组在构建模型前15 min和构建模型后5min分别给予生理盐水或白藜芦醇各一次。于构建模型后72小时利用NSS评分评估大鼠的神经功能,然后处死大鼠并获取保存脑组织。利用ELISA检测脑组织内促炎因子IL-1,IL-6、TNF-α和抗炎因子IL-4,IL-10、TGF-β的表达水平,利用RT-PCR检测小胶质细胞M1型特征性基因IL-1β、CD32和M2型特征性基因CD206、Arginase-1的表达水平。结果与假手术组相比,SAH组大鼠神经功能下降(P0.05),脑组织中促炎因子IL-1,IL-6、TNF-α和抗炎因子IL-4,IL-10、TGF-β的表达水平升高(P0.05),小胶质细胞M1型特征性基因IL-1β、CD32和M2型特征性基因CD206、Arginase-1的表达水平也升高(P 0.05)。与生理盐水处理组相比,白藜芦醇处理组神经功能损伤程度下降(P 0.05),脑组织中促炎因子IL-1,IL-6、TNF-α表达水平降低、抗炎因子IL-4,IL-10、TGF-β的表达水平升高(P 0.05),小胶质细胞M1型特征性基因IL-1β、CD32表达水平降低、M2型特征性基因CD206、Arginase-1的表达水平升高(P0.05)。结论白藜芦醇通过促进SAH后小胶质细胞由M1型向M2型转换,从而减轻了神经炎症和神经功能损伤。  相似文献   
10.
Estradiol, either from peripheral or central origin, activates multiple molecular neuroprotective and neuroreparative responses that, being mediated by estrogen receptors or by estrogen receptor independent mechanisms, are initiated at the membrane, the cytoplasm or the cell nucleus of neural cells. Estrogen-dependent signaling regulates a variety of cellular events, such as intracellular Ca2+ levels, mitochondrial respiratory capacity, ATP production, mitochondrial membrane potential, autophagy and apoptosis. In turn, these molecular and cellular actions of estradiol are integrated by neurons and non-neuronal cells to generate different tissue protective responses, decreasing blood-brain barrier permeability, oxidative stress, neuroinflammation and excitotoxicity and promoting synaptic plasticity, axonal growth, neurogenesis, remyelination and neuroregeneration. Recent findings indicate that the neuroprotective and neuroreparative actions of estradiol are different in males and females and further research is necessary to fully elucidate the causes for this sex difference.  相似文献   
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