Tumor necrosis factor alpha polymorphisms are associated with Parkinson's disease age at onset

Activity of a Novel Anti-Inflammatory Agent F-3,6'-dithiopomalidomide as a Treatment for Traumatic Brain Injury

Traumatic brain injury (TBI) is a major risk factor for several neurodegenerative disorders, including Parkinson's disease (PD) and Alzheimer's disease (AD). Neuroinflammation is a cause of later secondary cell death following TBI, has the potential to aggravate the initial impact, and provides a therapeutic target, albeit that has failed to translate into clinical trial success. Thalidomide-like compounds have neuroinflammation reduction properties across cellular and animal models of TBI and neurodegenerative disorders. They lower the generation of proinflammatory cytokines, particularly TNF-α which is pivotal in microglial cell activation. Unfortunately, thalidomide-like drugs possess adverse effects in humans before achieving anti-inflammatory drug levels. We developed F-3,6'-dithiopomalidomide (F-3,6'-DP) as a novel thalidomide-like compound to ameliorate inflammation. F-3,6'-DP binds to cereblon but does not efficiently trigger the degradation of the transcription factors (SALL4, Ikaros, and Aiolos) associated with the teratogenic and anti-proliferative responses of thalidomide-like drugs. We utilized a phenotypic drug discovery approach that employed cellular and animal models in the selection and development of F-3,6'-DP. F-3,6'-DP significantly mitigated LPS-induced inflammatory markers in RAW 264.7 cells, and lowered proinflammatory cytokine/chemokine levels in the plasma and brain of rats challenged with systemic LPS. We subsequently examined immunohistochemical, biochemical, and behavioral measures following controlled cortical impact (CCI) in mice, a model of moderate TBI known to induce inflammation. F-3,6'-DP decreased CCI-induced neuroinflammation, neuronal loss, and behavioral deficits when administered after TBI. F-3,6'-DP represents a novel class of thalidomide-like drugs that do not lower classical cereblon-associated transcription factors but retain anti-inflammatory actions and possess efficacy in the treatment of TBI and potentially longer-term neurodegenerative disorders.

Neurodegeneration by α-synuclein-specific T cells in AAV-A53T-α-synuclein Parkinson's disease mice

BACKGROUND

Antigen-specific neuroinflammation and neurodegeneration are characteristic for neuroimmunological diseases. In Parkinson's disease (PD) pathogenesis, α-synuclein is a known culprit. Evidence for α-synuclein-specific T cell responses was recently obtained in PD. Still, a causative link between these α-synuclein responses and dopaminergic neurodegeneration had been lacking. We thus addressed the functional relevance of α-synuclein-specific immune responses in PD in a mouse model.

METHODS

We utilized a mouse model of PD in which an Adeno-associated Vector 1/2 serotype (AAV1/2) expressing human mutated A53T-α-Synuclein was stereotactically injected into the substantia nigra (SN) of either wildtype C57BL/6 or Recombination-activating gene 1 (RAG1)^-/- mice. Brain, spleen, and lymph node tissues from different time points following injection were then analyzed via FACS, cytokine bead assay, immunohistochemistry and RNA-sequencing to determine the role of T cells and inflammation in this model. Bone marrow transfer from either CD4⁺/CD8^-, CD4^-/CD8⁺, or CD4⁺/CD8⁺ (JHD^-/-) mice into the RAG-1^-/- mice was also employed. In addition to the in vivo studies, a newly developed A53T-α-synuclein-expressing neuronal cell culture/immune cell assay was utilized.

RESULTS

AAV-based overexpression of pathogenic human A53T-α-synuclein in dopaminergic neurons of the SN stimulated T cell infiltration. RNA-sequencing of immune cells from PD mouse brains confirmed a pro-inflammatory gene profile. T cell responses were directed against A53T-α-synuclein-peptides in the vicinity of position 53 (68-78) and surrounding the pathogenically relevant S129 (120-134). T cells were required for α-synuclein-induced neurodegeneration in vivo and in vitro, while B cell deficiency did not protect from dopaminergic neurodegeneration.

CONCLUSIONS

Using T cell and/or B cell deficient mice and a newly developed A53T-α-synuclein-expressing neuronal cell culture/immune cell assay, we confirmed in vivo and in vitro that pathogenic α-synuclein peptide-specific T cell responses can cause dopaminergic neurodegeneration and thereby contribute to PD-like pathology.

Genetically Predicted Levels of Circulating Inflammatory Cytokines and the Risk and Age at Onset of Parkinson’s Disease: A Two-Sample Mendelian Randomization Study

Parkinson’s disease (PD) is widely considered to be a disabling neurodegenerative disorder, which has been ranked second worldwide just after Alzheimer’s disease. Until present, a wide range of studies has focused on the role of circulating inflammatory cytokines in the development of PD. However, the causal relationship between circulating inflammatory cytokines and the risk and age at the onset of PD has not been elucidated. Hence, to evaluate the effects of circulating inflammatory cytokines on the risk or age at the onset of PD more accurately, we conducted this two-sample Mendelian randomization (MR) study involving summary statistics from genome-wide association studies (GWASs). Totally, we included a GWAS for inflammatory cytokines (8,293 participants), a meta-analysis of GWASs for PD risk (482,730 participants), and a GWAS dataset for age at the onset of PD (17,996 patients with PD). A total of 149 and 131 polymorphisms for exploring relationships between 19 inflammatory cytokines and the risk and age at the onset of PD were obtained as instrumental variants. Then, we used a total of five MR methods, including inverse-variance weighted (IVW), Wald ratio, MR Egger regression, weighted median, and MR-pleiotropy residual sum and outlier (MR-PRESSO) methods. Finally, we found a causal association between circulating levels of macrophage inflammatory protein-1 beta (MIP1b) and PD risk in the IVW method (OR: 1.06; 95% CI: 1.02–1.10; P = 0.001). Meanwhile, other MR estimates by weighted median and MR-PRESSO methods yielded similar effect estimates. Besides, we identified a suggestive association of interleukin-16 (IL-16) levels with PD risk (OR: 1.08; 95% CI: 1.00–1.17; P = 0.037). For age at PD onset, there was no evidence supporting its correlation with inflammatory cytokines. Our findings implied that MIP1b and IL-16 may be novel biomarkers and promising therapeutic targets for PD development.

Prolactin and Its Altered Action in Alzheimer's Disease and Parkinson's Disease

BACKGROUND

Prolactin (PRL) is one of the most diverse pituitary hormones and is known to modulate normal neuronal function and neurodegenerative conditions. Many studies have described the influence that PRL has on the central nervous system and addressed its contribution to neurodegeneration, but little is known about the mechanisms responsible for the effects of PRL on neurodegenerative disorders, especially on Alzheimer's disease (AD) and Parkinson's disease (PD).

SUMMARY

We review and summarize the existing literature and current understanding of the roles of PRL on various PRL aspects of AD and PD.

KEY MESSAGES

In general, PRL is viewed as a promising molecule for the treatment of AD and PD. Modulation of PRL functions and targeting of immune mechanisms are needed to devise preventive or therapeutic strategies.

Transcriptome Analysis of Induced Pluripotent Stem Cells and Neuronal Progenitor Cells, Derived from Discordant Monozygotic Twins with Parkinson's Disease

Parkinson's Disease (PD) is a widespread severe neurodegenerative disease that is characterized by pronounced deficiency of the dopaminergic system and disruption of the function of other neuromodulator systems. Although heritable genetic factors contribute significantly to PD pathogenesis, only a small percentage of sporadic cases of PD can be explained using known genetic risk factors. Due to that, it could be inferred that changes in gene expression could be important for explaining a significant percentage of PD cases. One of the ways to investigate such changes, while minimizing the effect of genetic factors on experiment, are the study of PD discordant monozygotic twins. In the course of the analysis of transcriptome data obtained from IPSC and NPCs, 20 and 1906 differentially expressed genes were identified respectively. We have observed an overexpression of TNF in NPC cultures, derived from twin with PD. Through investigation of gene interactions and gene involvement in biological processes, we have arrived to a hypothesis that TNF could play a crucial role in PD-related changes occurring in NPC derived from twins with PD, and identified INHBA, WNT7A and DKK1 as possible downstream effectors of TNF.

Neuronal TNFα, Not α-Syn, Underlies PDD-Like Disease Progression in IFNβ-KO Mice

OBJECTIVE

Parkinson's disease (PD) manifests in motor dysfunction, non-motor symptoms, and eventual dementia (PDD). Neuropathological hallmarks include nigrostriatal neurodegeneration, Lewy body (LB) pathology, and neuroinflammation. Alpha-synuclein (α-syn), a primary component of LBs, is implicated in PD pathogenesis, accumulating, and aggregating in both familial and sporadic PD. However, as α-syn pathology is often comorbid with amyloid-beta (Aβ) plaques and phosphorylated tau (pTau) tangles in PDD, it is still unclear whether α-syn is the primary cause of neurodegeneration in sporadic PDD. We aimed to determine how the absence of α-syn would affect PDD manifestation.

METHODS

IFN-β knockout (Ifnb-/- ) mice spontaneously develop progressive behavior abnormalities and neuropathology resembling PDD, notably with α-syn+ LBs. We generated Ifnb/Snca double knockout (DKO) mice and evaluated their behavior and neuropathology compared with wild-type (Wt), Ifnb-/- , and Snca-/- mice using immunohistochemistry, electron microscopy, immunoblots, qPCR, and modification of neuronal signaling.

RESULTS

Ifnb/Snca DKO mice developed all clinical PDD-like behavioral manifestations induced by IFN-β loss. Independently of α-syn expression, lack of IFN-β alone induced Aβ plaques, pTau tangles, and LB-like Aβ+ /pTau+ inclusion bodies and neuroinflammation. IFN-β loss caused significant elevated glial and neuronal TNF-α and neuronal TNFR1, associated with neurodegeneration. Restoring neuronal IFN-β signaling or blocking TNFR1 rescued caspase 3/t-BID-mediated neuronal-death through upregulation of c-FLIPS and lowered intraneuronal Aβ and pTau accumulation.

INTERPRETATION

These findings increase our understanding of PD pathology and suggest that targeting α-syn alone is not sufficient to mitigate disease. Targeting specific aspects of neuroinflammation, such as aberrant neuronal TNF-α/TNFR1 or IFN-β/IFNAR signaling, may attenuate disease. ANN NEUROL 2021;90:789-807.

Immunomodulation with IL-17 and TNF-α in spondyloarthritis: focus on the eye and the central nervous system

Tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) are two pro-inflammatory cytokines involved in the pathophysiology of spondyloarthritis (SpA). Therapies targeting TNF-α or IL-17 are used as a second line among SpA patients failing non-steroidal anti-inflammatory drugs. The choice of such treatment has to take into account the patient’s comorbidities. Neurologic diseases are common and their association with SpA deserves to be studied. Therefore, the role of TNF-α and IL-17 cytokines is worth investigating in these neuropsychiatric diseases. This review aimed to explore the role of TNF-α and IL-17 in the pathogenesis of uveitis, multiple sclerosis, neuromyelitis optica, Alzheimer’s disease, Parkinson’s disease and depression. This update is critical to guide the therapeutic management of these co-morbidities in SpA patients.

Mild traumatic brain injury exacerbates Parkinson's disease induced hemeoxygenase-2 expression and brain pathology: Neuroprotective effects of co-administration of TiO2 nanowired mesenchymal stem cells and cerebrolysin

Mild traumatic brain injury (mTBI) is one of the leading predisposing factors in the development of Parkinson's disease (PD). Mild or moderate TBI induces rapid production of tau protein and alpha synuclein (ASNC) in the cerebrospinal fluid (CSF) and in several brain areas. Enhanced tau-phosphorylation and ASNC alters the molecular machinery of the brain leading to PD pathology. Recent evidences show upregulation of constitutive isoform of hemeoxygenase (HO-2) in PD patients that correlates well with the brain pathology. mTBI alone induces profound upregulation of HO-2 immunoreactivity. Thus, it would be interesting to explore whether mTBI exacerbates PD pathology in relation to tau, ASNC and HO-2 expression. In addition, whether neurotrophic factors and stem cells known to reduce brain pathology in TBI could induce neuroprotection in PD following mTBI. In this review role of mesenchymal stem cells (MSCs) and cerebrolysin (CBL), a well-balanced composition of several neurotrophic factors and active peptide fragments using nanowired delivery in PD following mTBI is discussed based on our own investigation. Our results show that mTBI induces concussion exacerbates PD pathology and nanowired delivery of MSCs and CBL induces superior neuroprotection. This could be due to reduction in tau, ASNC and HO-2 expression in PD following mTBI, not reported earlier. The functional significance of our findings in relation to clinical strategies is discussed.

Validation of an in vivo electrochemical immunosensing platform for simultaneous detection of multiple cytokines in Parkinson's disease mice model

Parkinson's Disease (PD) is a neurodegenerative chronic disorder which destroys brain tissue and result in impaired movement. Early diagnosis of PD before the appearance of clinical symptom is vital for effective treatment. High levels of proinflammatory cytokines found in PD patient's brains, as natural inflammation response product, are potential biomarkers for PD detection in the early stage. Herein, we developed an in vivo electrochemical immunosensing device based on glassy carbon rod to simultaneously detect three proinflammatory cytokines (IL-1β, IL-6 and TNF-α). The levels of IL-1β, IL-6 and TNF-α secreted by N2a cells significantly increased within 24 h after lipopolysaccharide (LPS) stimulation. Under in vivo conditions, the concentrations of IL-1β, IL-6 and TNF-α in PD model group achieved by injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intraperitoneally, were significantly higher than those in the control mouse group. The concentrations of three cytokines in vivo/vitro detected by this immunosensing device was comparable to that obtained by ELISA. Furthermore, this deployable immunosensing device was proved to be highly sensitive with the limits of detection (LODs) of 5 pg mL^-1 for each cytokine, specific and reliable, suggesting its potential to be a universal immunosensing platform for early identification and diagnosis of PD in vivo in the future.

Neuroinflammation as a Factor of Neurodegenerative Disease: Thalidomide Analogs as Treatments

Neuroinflammation is initiated when glial cells, mainly microglia, are activated by threats to the neural environment, such as pathogen infiltration or neuronal injury. Although neuroinflammation serves to combat these threats and reinstate brain homeostasis, chronic inflammation can result in excessive cytokine production and cell death if the cause of inflammation remains. Overexpression of tumor necrosis factor-α (TNF-α), a proinflammatory cytokine with a central role in microglial activation, has been associated with neuronal excitotoxicity, synapse loss, and propagation of the inflammatory state. Thalidomide and its derivatives, termed immunomodulatory imide drugs (IMiDs), are a class of drugs that target the 3'-untranslated region (3'-UTR) of TNF-α mRNA, inhibiting TNF-α production. Due to their multi-potent effects, several IMiDs, including thalidomide, lenalidomide, and pomalidomide, have been repurposed as drug treatments for diseases such as multiple myeloma and psoriatic arthritis. Preclinical studies of currently marketed IMiDs, as well as novel IMiDs such as 3,6'-dithiothalidomide and adamantyl thalidomide derivatives, support the development of IMiDs as therapeutics for neurological disease. IMiDs have a competitive edge compared to similar anti-inflammatory drugs due to their blood-brain barrier permeability and high bioavailability, with the potential to alleviate symptoms of neurodegenerative disease and slow disease progression. In this review, we evaluate the role of neuroinflammation in neurodegenerative diseases, focusing specifically on the role of TNF-α in neuroinflammation, as well as appraise current research on the potential of IMiDs as treatments for neurological disorders.

Differential expression of miR-4492 and IL-10 is involved in chronic rhinosinusitis with nasal polyps

Chronic rhinosinusitis (CRS) is one of the most common types of respiratory disease and affects a large proportion of the population worldwide. The clinical differences between CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP) facilitate studies on the development of polyps. In the present study, next-generation sequencing was performed to identify differentially expressed microRNAs (miRNAs/miRs) in CRSwNP vs. CRSsNP tissues and subsequently validated the expression of selected genes using reverse transcription-quantitative polymerase chain reaction analysis. In total, 6 miRNAs were identified to be downregulated in the CRSwNP samples compared with those in the CRSsNP samples. The predicted targets of these miRNAs were determined to be enriched in a number of signaling pathways, including the ErbB, Ras, cyclic adenosine monophosphate and Janus kinase (Jak)/signal transducer and activator of transcription (STAT) pathways. The expression of miR-4492 and that if its targets predicted by a bioinformatics analysis, tumor necrosis factor α (TNF-α) and interleukin (IL)-10, was validated in 96 clinical specimens. miR-4492 was downregulated and IL-10 was upregulated in CRSwNP vs. CRSsNP tissues, and an inverse correlation between miR-4492 and IL-10 was determined in CRS tissues; however no difference was identified in the expression of TNF-α between the different groups. The present results indicate that the miR-4492/IL-10 interaction in the Jak/STAT signaling pathway may be one of the key mechanisms in CRSwNP.

Heat-Shock Proteins in Neuroinflammation

The heat-shock response, one of the main pro-survival mechanisms of a living organism, has evolved as the biochemical response of cells to cope with heat stress. The most well-characterized aspect of the heat-shock response is the accumulation of a conserved set of proteins termed heat-shock proteins (HSPs). HSPs are key players in protein homeostasis acting as chaperones by aiding the folding and assembly of nascent proteins and protecting against protein aggregation. HSPs have been associated with neurological diseases in the context of their chaperone activity, as they were found to suppress the aggregation of misfolded toxic proteins. In recent times, HSPs have proven to have functions apart from the classical molecular chaperoning in that they play a role in a wider scale of neurological disorders by modulating neuronal survival, inflammation, and disease-specific signaling processes. HSPs are gaining importance based on their ability to fine-tune inflammation and act as immune modulators in various bodily fluids. However, their effect on neuroinflammation processes is not yet fully understood. In this review, we summarize the role of neuroinflammation in acute and chronic pathological conditions affecting the brain. Moreover, we seek to explore the existing literature on HSP-mediated inflammatory function within the central nervous system and compare the function of these proteins when they are localized intracellularly compared to being present in the extracellular milieu.

NR3C1, ABCB1, TNF and CYP2C19 polymorphisms association with the response to the treatment of erythema nodosum leprosum

Aim: To evaluate the effects of gene polymorphisms in the treatment of erythema nodosum leprosum with prednisone/thalidomide. Patients & methods: A total of 152 patients from different regions of Brazil were included. Generalized estimating equation was used to evaluate the influence of polymorphisms and haplotypes on the drug dose variation throughout the treatment. Results: An association between the genotype tuberculoid of polymorphism ABCB1 3435C>T (rs1045642; p = 0.02) and prednisone dose was found in the recessive model. An association between the haplotypes 1031T/-863C/-857C/-308A/-238G (p = 0.006) and 1031T/-863C/-857T/-308A/-238G (p = 0.040) of the TNF gene and the CYP2C19*2 polymorphism were also identified, in relation to thalidomide dosage variation over the course of treatment. Conclusion: This work presents the first pharmacogenetic report of association between gene polymorphisms and erythema nodosum leprosum treatment with prednisone/thalidomide.

Rosmarinic acid attenuates inflammatory responses through inhibiting HMGB1/TLR4/NF-κB signaling pathway in a mouse model of Parkinson's disease

Inflammation contributes to the pathological processes in patients and animal models of PD. Rosmarinic acid (RA) has been demonstrated to protect neurons in PD models. The present study aimed to evaluate the anti-inflammatory effect of RA on PD and reveal possible pharmacological mechanisms. 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) was injected to mice to establish PD model in vivo. BV-2 cells were exposed to 1-methyl-4-phenylpyridinium (MPP+) and α-synuclein to establish PD model in vitro. Results showed that treatment with RA dose-dependently improved motor function of PD mice, increased the number of tyrosine hydroxylase-positive cells, reduced production of pro-inflammatory cytokines, and inhibited microglia activation in ventral midbrain. In cell study, RA also decreased MPP+ or α-synuclein-induced secretion of pro-inflammatory cytokines. Furthermore, RA treatment downregulated the expression levels of HMGB1, TLR4 and Myd88 and inhibited NF-κB nuclear expression both in PD animal and cell models. These findings indicated that RA could attenuate inflammatory responses through suppressing HMGB1/TLR4/NF-κB signaling pathway, which may contribute to its anti-PD activity.

The Dual Role of Hepcidin in Brain Iron Load and Inflammation

Hepcidin is the major regulator of systemic iron metabolism, while the role of this peptide in the brain has just recently been elucidated. Studies suggest a dual role of hepcidin in neuronal iron load and inflammation. This is important since neuronal iron load and inflammation are pathophysiological processes frequently associated with neurodegeneration. Furthermore, manipulation of hepcidin activity has recently been used to recover neuronal damage due to brain inflammation in animal models and cultured cells. Therefore, understanding the mechanistic insights of hepcidin action in the brain is important to uncover its role in treating neuronal damage in neurodegenerative diseases.

A New Venue of TNF Targeting

The first Food and Drug Administration-(FDA)-approved drugs were small, chemically-manufactured and highly active molecules with possible off-target effects, followed by protein-based medicines such as antibodies. Conventional antibodies bind a specific protein and are becoming increasingly important in the therapeutic landscape. A very prominent class of biologicals are the anti-tumor necrosis factor (TNF) drugs that are applied in several inflammatory diseases that are characterized by dysregulated TNF levels. Marketing of TNF inhibitors revolutionized the treatment of diseases such as Crohn’s disease. However, these inhibitors also have undesired effects, some of them directly associated with the inherent nature of this drug class, whereas others are linked with their mechanism of action, being pan-TNF inhibition. The effects of TNF can diverge at the level of TNF format or receptor, and we discuss the consequences of this in sepsis, autoimmunity and neurodegeneration. Recently, researchers tried to design drugs with reduced side effects. These include molecules with more specificity targeting one specific TNF format or receptor, or that neutralize TNF in specific cells. Alternatively, TNF-directed biologicals without the typical antibody structure are manufactured. Here, we review the complications related to the use of conventional TNF inhibitors, together with the anti-TNF alternatives and the benefits of selective approaches in different diseases.

The Role of Immunosenescence in Neurodegenerative Diseases

Aging is characterized by the progressive decline of physiological function and tissue homeostasis leading to increased vulnerability, degeneration, and death. Aging-related changes of the innate and adaptive immune system include decline in the preservation and enhancement of many immune functions, such as changes in the number of circulating monocytic and dendritic cells, thymic involution, T cell polyfunctionality, or production of proinflammatory cytokines, and are defined as immunosenescence. Inflammatory functions are increased with age, causing the chronic low-grade inflammation, referred to as inflamm-aging, that contribute, together with immunosenescence, to neurodegenerative diseases. In this review, we discuss the link between the immune and nervous systems and how the immunosenescence and inflamm-aging can contribute to neurodegenerative diseases.