scholarly journals An Immunological Approach to Increase the Brain’s Resilience to Insults

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
En-Ju D. Lin ◽  
C. Wymond Symes ◽  
Andrea Townsend-Nicholson ◽  
Matthias Klugmann ◽  
Claudia B. Klugmann ◽  
...  

We have previously demonstrated the therapeutic potential of inducing a humoral response with autoantibodies to the N-methyl D-aspartate (NMDA) receptor using a genetic approach. In this study, we generated three recombinant proteins to different functional domains of the NMDA receptor, which is implicated in mediating brain tolerance, specifically NR1[21–375], NR1[313–619], NR1[654–800], and an intracellular scaffolding protein, Homer1a, with a similar anatomical expression pattern. All peptides showed similar antigenicity and antibody titers following systemic vaccination, and all animals thrived. Two months following vaccination, rats were administered the potent neurotoxin, kainic acid. NR1[21–375] animals showed an antiepileptic phenotype but no neuroprotection. Remarkably, despite ineffective antiepileptic activity, 6 of 7 seizing NR1[654–800] rats showed absolutely no injury with only minimal changes in the remaining animal, whereas the majority of persistently seizing rats in the other groups showed moderate to severe hippocampal injury. CREB, BDNF, and HSP70, proteins associated with preconditioning, were selectively upregulated in the hippocampus of NR1[654–800] animals, consistent with the observed neuroprotective phenotype. These results identify NR1 epitopes important in conferring anticonvulsive and neuroprotective effects and support the concept of an immunological strategy to induce a chronic state of tolerance in the brain.

2020 ◽  
Author(s):  
Joseph Bryant ◽  
Sanketh Andhavarapu ◽  
Christopher Bever ◽  
Poornachander Guda ◽  
Akhil Katuri ◽  
...  

Abstract Background: The combined antiretroviral therapy (cART) era has significantly increased the lifespan of HIV patients, turning a fatal disease to a chronic one. However, this lower but persistent level of HIV infection increases the susceptibility of HIV-associated neurocognitive disorder (HAND). Therefore, research is currently seeking improved treatment for this complication of HIV. In HIV+ patients, low levels of brain derived neurotrophic factor (BDNF) has been associated with worse neurocognitive impairment. Hence, BDNF administration has been gaining relevance as a possible adjunct therapy for HAND. However, systemic administration of BDNF is impractical because of poor pharmacological profile.Methods: We investigated the neuroprotective effects of BDNF-mimicking 7,8 dihydroxyflavone (DHF), a bioactive high-affinity TrkB agonist, in the memory-involved hippocampus and brain cortex of Tg26 mice, a murine model for HAND. We immunohistochemically stained brain tissue sections from vehicle-treated wild type (WT), vehicle-treated Tg26, and DHF (5 mg/kg, i.p)-treated Tg26 mice to examine activation of TrkB and downstream signaling, expression of HIV-1 chemokine co-receptors CXCR4 and CCR5, neuroinflammation, and mitochondrial damage. A one-way ANOVA with a Bonferroni Comparison post-hoc test was performed to analyze the data sets. Results: In the brain regions of Tg26 mice, we observed astrogliosis, increased CXCR4 and CCR5 expression, neuroinflammation, and mitochondrial damage. Hippocampi and cortices of DHF treated mice exhibited a reversal of these pathological changes, suggesting the therapeutic potential of DHF in HAND. Our data indicates that DHF increases the phosphorylation of TrkB, providing new insights about the role of the TrkB-Akt-NFkB signaling pathway in mediating these pathological hallmarks.Conclusions: Our study provides an overview of how targeting BDNF-TrkB signaling in the pathophysiology of HAND may be relevant for future therapies, and sheds light on 7,8 Dihydroxyflavone as a potential adjunct therapeutic agent to current antiviral therapy.


2021 ◽  
Vol 14 ◽  
Author(s):  
Lisha Ye ◽  
Yechao Sun ◽  
Zhenglin Jiang ◽  
Guohua Wang

Central nervous system (CNS) lesions are major causes of human death and disability worldwide, and they cause different extents of motor and sensory dysfunction in patients. Thus, it is crucial to develop new effective neuroprotective drugs and approaches targeted to the heterogeneous nature of CNS injury and disease. L-serine is an indispensable neurotrophic factor and a precursor for neurotransmitters. Although L-serine is a native amino acid supplement, its metabolic products have been shown to be essential not only for cell proliferation but also for neuronal development and specific functions in the brain. Growing evidence has suggested that L-serine regulates the release of several cytokines in the brain under some neuropathological conditions to recover cognitive function, improve cerebral blood flow, inhibit inflammation, promote remyelination and exert other neuroprotective effects on neurological injury. L-serine has also been used to treat epilepsy, schizophrenia, psychosis, and Alzheimer’s Disease as well as other neurological diseases. Furthermore, the dosing of animals with L-serine and human clinical trials investigating the therapeutic effects of L-serine generally support the safety of L-serine. The high significance of this review lies in its emphasis on the therapeutic potential of using L-serine as a general treatment for numerous CNS diseases and injuries. Because L-serine performs a broad spectrum of functions, it may be clinically used as an effective neuroprotective agent.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joseph Bryant ◽  
Sanketh Andhavarapu ◽  
Christopher Bever ◽  
Poornachander Guda ◽  
Akhil Katuri ◽  
...  

AbstractThe combined antiretroviral therapy era has significantly increased the lifespan of people with HIV (PWH), turning a fatal disease to a chronic one. However, this lower but persistent level of HIV infection increases the susceptibility of HIV-associated neurocognitive disorder (HAND). Therefore, research is currently seeking improved treatment for this complication of HIV. In PWH, low levels of brain derived neurotrophic factor (BDNF) has been associated with worse neurocognitive impairment. Hence, BDNF administration has been gaining relevance as a possible adjunct therapy for HAND. However, systemic administration of BDNF is impractical because of poor pharmacological profile. Therefore, we investigated the neuroprotective effects of BDNF-mimicking 7,8 dihydroxyflavone (DHF), a bioactive high-affinity TrkB agonist, in the memory-involved hippocampus and brain cortex of Tg26 mice, a murine model for HAND. In these brain regions, we observed astrogliosis, increased expression of chemokine HIV-1 coreceptors CXCR4 and CCR5, neuroinflammation, and mitochondrial damage. Hippocampi and cortices of DHF treated mice exhibited a reversal of these pathological changes, suggesting the therapeutic potential of DHF in HAND. Moreover, our data indicates that DHF increases the phosphorylation of TrkB, providing new insights about the role of the TrkB–Akt–NFkB signaling pathway in mediating these pathological hallmarks. These findings guide future research as DHF shows promise as a TrkB agonist treatment for HAND patients in adjunction to the current antiviral therapies.


Neurology ◽  
2016 ◽  
Vol 88 (4) ◽  
pp. 366-370 ◽  
Author(s):  
Franziska Scheibe ◽  
Harald Prüss ◽  
Annerose M. Mengel ◽  
Siegfried Kohler ◽  
Astrid Nümann ◽  
...  

Objective:We assessed the therapeutic potential of the plasma-cell-depleting proteasome inhibitor bortezomib in severe and therapy-refractory cases of anti–NMDA receptor (anti-NMDAR) encephalitis.Methods:Five severely affected patients with anti-NMDAR encephalitis with delayed treatment response or resistance to standard immunosuppressive and B-cell-depleting drugs (corticosteroids, IV immunoglobulins, plasma exchange, immunoadsorption, rituximab, cyclophosphamide) who required medical treatment and artificial ventilation on intensive care units were treated with 1–6 cycles of 1.3 mg/m2 bortezomib. Occurrence of adverse events was closely monitored.Results:Bortezomib treatment showed clinical improvement or disease remission, which was accompanied by a partial NMDAR antibody titer decline in 4 of 5 patients. With respect to disease severity, addition of bortezomib to the multimodal immunosuppressive treatment regimen was associated with an acceptable safety profile.Conclusions:Our study identifies bortezomib as a promising escalation therapy for severe and therapy-refractory anti-NMDAR encephalitis.Classification of evidence:This retrospective case series provides Class IV evidence that bortezomib reduces antibody titers and improves the clinical course of patients with severe anti-NMDAR encephalitis.


Author(s):  
Hannah R. Brown ◽  
Anthony F. Nostro ◽  
Halldor Thormar

Subacute sclerosing panencephalitis (SSPE) is a slowly progressing disease of the CNS in children which is caused by measles virus. Ferrets immunized with measles virus prior to inoculation with the cell associated, syncytiogenic D.R. strain of SSPE virus exhibit characteristics very similar to the human disease. Measles virus nucleocapsids are present, high measles antibody titers are found in the sera and inflammatory lesions are prominent in the brains. Measles virus specific immunoglobulin G (IgG) is present in the brain,and IgG/ albumin ratios indicate that the antibodies are synthesized within the CNS.


Author(s):  
Hannah R. Brown ◽  
Tammy L. Donato ◽  
Halldor Thormar

Measles virus specific immunoglobulin G (IgG) has been found in the brains of patients with subacute sclerosing panencephalitis (SSPE), a slowly progressing disease of the central nervous system (CNS) in children. IgG/albumin ratios indicate that the antibodies are synthesized within the CNS. Using the ferret as an animal model to study the disease, we have been attempting to localize the Ig's in the brains of animals inoculated with a cell associated strain of SSPE. In an earlier report, preliminary results using Protein A conjugated to horseradish peroxidase (PrAPx) (Dynatech Diagnostics Inc., South Windham, ME.) to detect antibodies revealed the presence of immunoglobulin mainly in antibody-producing plasma cells in inflammatory lesions and not in infected brain cells.In the present experiment we studied the brain of an SSPE ferret with neutralizing antibody titers of 1:1024 in serum and 1:512 in CSF at time of sacrifice 7 months after i.c. inoculation with SSPE measles virus-infected cells. The animal was perfused with saline and portions of the brain and spinal cord were immersed in periodate-lysine-paraformaldehyde (P-L-P) fixative. The ferret was not perfused with fixative because parts of the brain were used for virus isolation.


2018 ◽  
Vol 25 (28) ◽  
pp. 3333-3352 ◽  
Author(s):  
Natalia Pessoa Rocha ◽  
Ana Cristina Simoes e Silva ◽  
Thiago Ruiz Rodrigues Prestes ◽  
Victor Feracin ◽  
Caroline Amaral Machado ◽  
...  

Background: The Renin-Angiotensin System (RAS) is a key regulator of cardiovascular and renal homeostasis, but also plays important roles in mediating physiological functions in the central nervous system (CNS). The effects of the RAS were classically described as mediated by angiotensin (Ang) II via angiotensin type 1 (AT1) receptors. However, another arm of the RAS formed by the angiotensin converting enzyme 2 (ACE2), Ang-(1-7) and the Mas receptor has been a matter of investigation due to its important physiological roles, usually counterbalancing the classical effects exerted by Ang II. Objective: We aim to provide an overview of effects elicited by the RAS, especially Ang-(1-7), in the brain. We also aim to discuss the therapeutic potential for neuropsychiatric disorders for the modulation of RAS. Method: We carried out an extensive literature search in PubMed central. Results: Within the brain, Ang-(1-7) contributes to the regulation of blood pressure by acting at regions that control cardiovascular functions. In contrast with Ang II, Ang-(1-7) improves baroreflex sensitivity and plays an inhibitory role in hypothalamic noradrenergic neurotransmission. Ang-(1-7) not only exerts effects related to blood pressure regulation, but also acts as a neuroprotective component of the RAS, for instance, by reducing cerebral infarct size, inflammation, oxidative stress and neuronal apoptosis. Conclusion: Pre-clinical evidence supports a relevant role for ACE2/Ang-(1-7)/Mas receptor axis in several neuropsychiatric conditions, including stress-related and mood disorders, cerebrovascular ischemic and hemorrhagic lesions and neurodegenerative diseases. However, very few data are available regarding the ACE2/Ang-(1-7)/Mas receptor axis in human CNS.


2020 ◽  
Vol 26 ◽  
Author(s):  
Nimra Javaid ◽  
Muhammad Ajmal Shah ◽  
Azhar Rasul ◽  
Zunera Chauhdary ◽  
Uzma Saleem ◽  
...  

: Neurodegeneration is a multifactorial process involved the different cytotoxic pathways that lead towards neuronal cell death. Alzheimer’s disease (AD) is a persistent neurodegenerative disorder that normally has a steady onset yet later on it worsens. The documented evidence of AD neuropathology manifested the neuro-inflammation, increased reactive oxygen, nitrogen species and decreased antioxidant protective process; mitochondrial dysfunction as well as increased level of acetylcholinesterase activity. Moreover, enhanced action of proteins leads towards neural apoptosis which have a vital role in the degeneration of neurons. The inability of commercial therapeutic options to treat AD with targeting single mechanism leads the attraction towards organic drugs. Ellagic acid is a dimer of gallic acid, latest studies expressed that ellagic acid can initiate the numerous cell signaling transmission and decrease the progression of disorders, involved in the degeneration of neurons. The influential property of ellagic acid to protect the neurons in neurodegenerative disorders is due to its antioxidant effect, iron chelating and mitochondrial protective effect. The main goal of this review is to critically analyze the molecular mode of action of ellagic acid against neurodegeneration.


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