CNS & Neurological Disorders - Drug Targets - Volume 16, Issue 10, 2017

Background: NF-ΚB is a ubiquitous transcription factor that was discovered three decades ago. Since its discovery, this protein complex has been implicated in numerous physiological and pathophysiological processes such as synaptic plasticity, learning and memory, inflammation, insulin resistance, and oxidative stress among other factors that are intricately involved and dysregulated in Alzheimer's disease (AD). Methods: We embarked on a methodical and an objective review of contemporary literature to integrate the indispensable physiological functions of NF-ΚB in neuronal phsyiology with the undesirable pathophysiological attributes of NF-ΚB in the etiopathogenesis of Alzheimer's disease. In our approach, we first introduced Alzheimer's disease and subsequently highlighted the multifaceted roles of NF-ΚB in the biological processes altered in the progression of Alzheimer's disease including synaptic transmission, synaptic plasticity, learning, and memory, neuronal survival and apoptosis, adult neurogenesis, regulation of neural processes and structural plasticity, inflammation, and Amyloid-β production and toxicity. Results: Our comprehensive review highlights and dissects the physiological role of NF-ΚB from its pathological role in the brain and delineates both, its beneficial as well as deleterious, role in the etiopathogenesis of Alzheimer's disease. Conclusion: In light of our understanding of the duality of the role of NF-ΚB in the pathogenesis of Alzheimer's disease, further studies are warranted to dissect and understand the basis of the dichotomous effects of NF-ΚB, so that certain selective benevolent and benign attributes of NF-ΚB can be spared while targeting its deleterious attributes and facets that are integral in the pathogenesis of Alzheimer's disease.

Background & Objective: Since its initial discovery, current understanding on the functional role of the Receptor for Advanced Glycation End-products (RAGE) in physiology and in pathology has impressively grown, especially in consideration of its large ligand repertoire (AGEs, HMGB-1, β amyloid, S100B/S100A12) and its potential involvement in the pathophysiology of several chronic human disorders. Downstream RAGE engagement by its ligands, NF-ΚB signaling activation has been demonstrated in several cell phenotypes, including neurons and glia. Based on the observation that in Alzheimer's Disease (AD) brain expression of RAGE and its ligands is upregulated and that RAGE/NF-ΚB axis activation can trigger an autoregulatory loop which further amplifies neuroinflammation and neurodegeneration, this signaling pathway has been hypothesized to greatly contribute to AD pathophysiology. Herein we review the vast array of information supporting a detrimental role of RAGE/NF-ΚB axis activation in AD brain and discuss those data in the context of recent findings obtained in our laboratory pointing to an unexpected effect elicited by this signaling pathway which may rather contribute to reparative mechanisms in AD, namely positive modulation of adult neurogenesis. Interestingly, the proneurogenic effect resulting from RAGE/NF-ΚB axis activation could be induced by molecules which are commonly considered as mediators of toxicity, like Aβ oligomers and HMGB-1. Conclusion: Altogether, despite a large set of data suggesting that RAGE may represent an interesting target for the pharmacological treatment of AD, the complex functional roles of the receptor would require the use of molecules able to counteract RAGE negative effects without altering the positive ones such as the promotion of adult neurogenesis.

Background & Objective: The innate immune response is a common occurrence in many neuroinflammatory diseases. Central Nervous System (CNS) resident immune cells are able to detect and react to infections and sterile trauma. Peripheral immune cell migration into CNS is regulated by the blood-brain barrier, although peripheral immune cells can invade CNS through meninges, choroid plexus, perivascular spaces, and cerebrospinal fluid. Consequently, in the brain, immune reactions can be mediated by both resident and peripheral immune cells. Both in the periphery and within the CNS, innate immune response is regulated by a wide array of pattern recognition receptors, including Tolllike, scavenger, Retinoic Acid-inducible Gene-1 like, and nucleotide-binding oligomerization domainslike responsible for inflammasome formation. Inflammasome pathway activation induces pyroptosis, a highly inflammatory cell death pattern that occurs to remove intracellular pathogens. Legionella pneumophila is an intracellular microorganism responsible for Legionnaires' disease, a lung infection always associated to neurological dysfunctions. Recent studies have been shown that Toll-like receptors, nucleotide-binding oligomerization domains-like receptors, and RIG-1 like, are activated by L. pneumophila. This flagellated bacterium is able to replicate in phagocytic cells, including macrophages and microglia, responding by activating inflammasome pathways that may be the cause of CNS dysfunction detected in several infected patients. Conclusion: The aim of this review is to bring together the latest findings concerning L. pneumophila infection and innate immune host cell responses. A deeper knowledge of these processes could allow the use of immunomodulatory compounds able to counteract CNS involvement following L. pneumophila infection.

Background & Objective: Gliomas constitute 81% of malignant brain tumors and exhibit a poor prognosis. Two main events involved in the progression of gliomas are the deregulation of genes via genetic events and the cellular damage resulting from the formation of reactive oxygen species (ROS). In gliomas, epigenetic abnormalities implicated in the deregulation of deoxyribonucleic acid (DNA) methylation, nucleosome rearrangement, and acetylation of histones, have been depicted. The overproduction of ROS has been implicated in the promotion of these modifications. Conclusion: In this review, we discuss the epigenetic mechanisms and oxidative events that impact gene silencing and its association with the establishment and development of gliomas. Some of these epigenetic marks, or their related proteins, are under investigation for their potential use as biomarkers in clinical trials to propose personalized therapies for patients with glioblastoma.

Background & Objective: 6-[(1S)-1-[1-[5-(2-hydroxyethoxy)-2-pyridyl]pyrazol-3-yl]ethyl]- 3H-1,3-benzothiazol-2-one (LY3130481 or CERC-611) is a selective antagonist of AMPA receptors containing transmembrane AMPA receptor regulatory protein (TARP) γ-8 that is under development for epilepsy. The present study provided a broad inquiry into its anticonvulsant properties. LY3130481 was anticonvulsant in multiple acute seizure provocation models in mice and rats. In addition, LY3130481 was effective against absence seizures in the GAERS genetic model and in the Frings mouse model. Likewise, LY3130481 attenuated convulsions in mice and rats with long-term induction of seizures (e.g., corneal, pentylenetetrazole, hippocampal, and amygdala kindled seizures). In slices of epileptic human cortex, LY3130481 significantly decreased neuronal firing frequencies. LY3130481 displaced from rat brain a radioligand specific for AMPA receptors associated with TARP γ-8 whereas non-TARP-selective molecules did not. Binding was also observed in hippocampus freshly transected from a patient. Results & Conclusion: Taken as a whole, the findings reported here establish the broad anticonvulsant efficacy of LY3130481 indicating that blockade of AMPA receptors associated with TARP γ-8 is sufficient for these protective effects.

Background: Chronic cerebral hypoperfusion is a common pathophysiological state in various cerebrovascular diseases. Anisodine has been reported to exert neuroprotective effects in cerebral ischemia/reperfusion (I/R) animal model. However, it is unclear whether anisodine hydrobromide, the hydrobromide format of anisodine, one of the tropic alkanes alkaloids, exhibits the same neuroprotective effect on chronic cerebral hypoperfusion(CCH) rats. Herein, we tried to unravel these issues. Methods: CCH model in adult male Sprague-Dawley rats was established by permanent ligation of the bilateral common carotid arteries [two-vessel occlusion (2-VO)] surgery. Rats were randomly divided into six groups: sham, 2-VO, 2-VO + Butyl phthalide and sodium chloride injection (NBP, as positive control group), 2-VO + anisodine hydrobromide (AH)1.2mg/kg, 2-VO +AH0.6mg/kg, 2-VO +AH0.3mg/kg. Cognitive behavior was examined by Morris Water Maze Test. Neuronal survival and apoptosis were evaluated by Nissl staining and Terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL staining). The relative monoamine neurotransmitter (5-hydroxytryptamine (5-HT), norepinephrine (NA)), the content of Ach, the activity of acetylcholin esterase (AchE) were measured in cholinergic system, and the protein expressions of Bcl-2, Bax, p-Akt and p-GSK-3βwere detected by Western blot assay. Results: The results showed that there is significant memory impairment and a remarkable neuron necrosis and apoptosis, along with the dysfunction of the neurotransmitter systems and central cholinergic system in CCH rats. AH treatment could significantly improve cognitive deficits, while reducing neuron necrosis and apoptosis, apart from increasing the content of 5-HT and decreasing the activity of AchE markedly. Further study revealed that AH could promote the protein expression of Bcl-2, phosphorylation of Akt and GSK-3β, and downregulate the protein of Bax. Conclusion: AH was demonstrated to ameliorate memory deficits by revising the imbalance of the monoamine neurotransmitter and cholinergic dysfunction. Moreover, AH can attenuate neuronal cell death and apoptosis by activating the Akt/GSK-3βsignaling pathway.

Background: Migraine is an episodic headache, which is an endothelial disorder with neurological inflammation. Intercellular Adhesion Molecule-1 (ICAM-1), as an endothelial factor, leads to the adhesion of leukocytes to the walls of the cerebral blood vessels, which is an important step in the inflammation process. Curcumin and omega-3 fatty acids, by affecting transcription factors, can regulate the gene expression and serum levels of ICAM-1. Thus, this study aimed to evaluate the synergistic effects of ω-3 fatty acids and nano-curcumin on ICAM-1 gene expression and serum levels in migraine patients. Method: This clinical trial study was conducted on 72 episodic migraine patients in 4 groups for 2 months, with patients receiving ω-3 fatty acids, nano-curcumin, a combination of them, or a placebo during the study. At the beginning and end of the study, the gene expression and serum level of ICAM-1 were measured by real-time PCR and ELISA. Result: The results showed no significant change in ICAM-1 gene expression in any of the 4 groups. The ICAM-1 serum concentration in the combination group, and omega-3 alone, showed a significant reduction at the end of the study compared to the beginning. In addition, a significant reduction in attack frequency was observed in the combination group. Conclusion: Considering the results of supplementation with omega-3 fatty acids plus curcumin led to reductions of both attack frequency and ICAM-1 serum level in patients, it seems that supplementation with these two nutrients not only can lead to improvements in the function of metabolic pathways, but can also be used effectively as a treatment or prevention of migraine complications.

Background and Objective: Asenapine is an atypical antipsychotic approved by US Food and Drug Administration in 2009 and by European Medicines Agency in 2010 for Schizophrenia and Bipolar Disorder treatment. Currently, many studies have been developed in an attempt to clarify and minimize the risks related to the use of psychotropic during pre/postnatal period on patients with a history of mental disorders. Conclusion: The aim of this study was to test the impact of pre and/or postnatal exposition to asenapine on mice offspring behavior. Four groups of animals, previously treated with a dosage equivalent to 50% of the bioavailability obtained with a 20 mg daily use for human treatment, were exposed to the Open Field and Elevated plus Maze test. Only the group exposed to asenapine during both pre and postnatal periods showed response difference in the Elevated Plus Maze test, which was restricted to urination. However, our data suggest that the administration of asenapine does not induce significant anxiety-like behaviors in mice.