Neurodegenerative diseases (NDDs) are predicted to be the biggest health concern in this century and the second leading cause of death by 2050. The main risk factor of these diseases is aging, and as ...the aging population in Western societies is increasing, the prevalence of these diseases is augmenting exponentially. Despite the great efforts to find a cure, current treatments remain ineffective or have low efficacy. Increasing lines of evidence point to exacerbated oxidative stress, mitochondrial dysfunction and chronic neuroinflammation as common pathological mechanisms underlying neurodegeneration. We will address the role of the nuclear factor E2-related factor 2 (Nrf2) as a potential target for the treatment of NDDs. The Nrf2-ARE pathway is an intrinsic mechanism of defence against oxidative stress. Nrf2 is a transcription factor that induces the expression of a great number of cytoprotective and detoxificant genes. There are many evidences that highlight the protective role of the Nrf2-ARE pathway in neurodegenerative conditions, as it reduces oxidative stress and neuroinflammation. Therefore, the Nrf2 pathway is being increasingly considered a therapeutic target for NDDs. Herein we will review the deregulation of the Nrf2 pathway in different NDDs and the recent studies with Nrf2 inducers as "proof-of-concept" for the treatment of those devastating pathologies.
Activation of the peripheral immune system elicits a coordinated response from the central nervous system. Key to this immune to brain communication is that glia, microglia, and astrocytes, interpret ...and propagate inflammatory signals in the brain that influence physiological and behavioral responses. One issue in glial biology is that morphological analysis alone is used to report on glial activation state. Therefore, our objective was to compare behavioral responses after in vivo immune (lipopolysaccharide, LPS) challenge to glial specific mRNA and morphological profiles. Here, LPS challenge induced an immediate but transient sickness response with decreased locomotion and social interaction. Corresponding with active sickness behavior (2–12 h), inflammatory cytokine mRNA expression was elevated in enriched microglia and astrocytes. Although proinflammatory cytokine expression in microglia peaked 2‐4 h after LPS, astrocyte cytokine, and chemokine induction was delayed and peaked at 12 h. Morphological alterations in microglia (Iba‐1+) and astrocytes (GFAP+), however, were undetected during this 2–12 h timeframe. Increased Iba‐1 immunoreactivity and de‐ramified microglia were evident 24 and 48 h after LPS but corresponded to the resolution phase of activation. Morphological alterations in astrocytes were undetected after LPS. Additionally, glial cytokine expression did not correlate with morphology after four repeated LPS injections. In fact, repeated LPS challenge was associated with immune and behavioral tolerance and a less inflammatory microglial profile compared with acute LPS challenge. Overall, induction of glial cytokine expression was sequential, aligned with active sickness behavior, and preceded increased Iba‐1 or GFAP immunoreactivity after LPS challenge. GLIA 2016;64:300–316
Main points
Glial induction of cytokines was sequential, aligned with active sickness behavior, and preceded increased Iba1 or GFAP immunoreactivity after LPS challenge.
Microglial Iba1 or astrocytic GFAP immunoreactivity are unreliable indicators of activation.
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Nicotinic acetylcholine receptors (nAChRs) are widely distributed throughout the central nervous system, being expressed in neurons and non-neuronal cells, where they participate in a ...variety of physiological responses like memory, learning, locomotion, attention, among others. We will focus on the α7 nAChR subtype, which has been implicated in neuroprotection, synaptic plasticity and neuronal survival, and is considered as a potential therapeutic target for several neurological diseases. Oxidative stress and neuroinflammation are currently considered as two of the most important pathological mechanisms common in neurodegenerative diseases such as Alzheimer, Parkinson or Huntington diseases. In this review, we will first analysed the distribution and expression of nAChR in mammalian brain. Then, we focused on the function of the α7 nAChR subtype in neuronal and non-neuronal cells and its role in immune responses (cholinergic anti-inflammatory pathway). Finally, we will revise the anti-inflammatory pathway promoted via α7 nAChR activation that is related to recruitment and activation of Jak2/STAT3 pathway, which on the one hand inhibits NF-κB nuclear translocation, and on the other hand, activates the master regulator of oxidative stress Nrf2/HO-1. This review provides a profound insight into the role of the α7 nAChR subtype in microglia and point out to microglial α7/HO-1 pathway as an anti-inflammatory therapeutic target.
Genome-Wide Association Studies (GWAS) have elucidated the genetic components of Parkinson's Disease (PD). However, because the vast majority of GWAS association signals fall within non-coding ...regions, translating these results into an interpretable, mechanistic understanding of the disease etiology remains a major challenge in the field. In this review, we provide an overview of the approaches to prioritize putative causal variants and genes as well as summarise the primary findings of previous studies. We then discuss recent efforts to integrate multi-omics data to identify likely pathogenic cell types and biological pathways implicated in PD pathogenesis. We have compiled full summary statistics of cell-type, tissue, and phentoype enrichment analyses from multiple studies of PD GWAS and provided them in a standardized format as a resource for the research community (https://github.com/RajLabMSSM/PD_omics_review). Finally, we discuss the experimental, computational, and conceptual advances that will be necessary to fully elucidate the effects of functional variants and genes on cellular dysregulation and disease risk.
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A review of: Laura Fernández-González, Philip II of Spain and the Architecture of Empire, Pittsburgh: Penn State Press, 2021, 176 pages, ISBN 978-0-271-08724-5. This is a review of the publication by ...Laura Fernández-González, Philip II of Spain and the Architecture of Empire (2021). Through a detailed analysis of buildings and building regulation, the architecture of archives, festivals and celebratory frescoes, the author shows the complexity and diversity of the architecture of the Spanish empire. The book is a refreshing study on the self-fashioning of Philip II and the role of architecture in the construction of the Spanish Empire.
SCOPE: We have studied if curcumin can protect glial cells under an oxidative stress and inflammatory environment, which is known to be deleterious in neurodegeneration. METHODS AND RESULTS: Primary ...rat glial cultures exposed to the combination of an oxidative (rotenone/oligomycin A) and a proinflammatory LPS stimuli reduced by 50% glial viability. Under these experimental conditions, curcumin afforded significant glial protection and reduction of reactive oxygen species; these effects were blocked by the HO‐1 inhibitor tin protoporphyrin‐IX (SnPP). These findings correlate with the observation that curcumin induced the antioxidative protein HO‐1. Most interesting was the observation that the glial protective effects related to HO‐1 induction were microglial specific as shown in glial cultures from LysMCʳᵉHmox∆/∆ mice where curcumin lost its protective effect. Under LPS conditions, curcumin reduced the microglial proinflammatory markers iNOS and tumor necrosis factor, but increased the anti‐inflammatory cytokine IL4. Analysis of the microglial phenotype showed that curcumin favored a ramified morphology toward a microglial alternative activated state against LPS insult also by a HO‐1‐dependent mechanism. CONCLUSION: The curry constituent curcumin protects glial cells and promotes a microglial anti‐inflammatory phenotype by a mechanism that implicates HO‐1 induction; these effects may have impact on brain protection under oxidative and inflammatory conditions.
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Naringin is one of the main flavonoids in citrus fruits and byproducts. This flavanone has been shown to be a good antioxidant nutraceutical component, and it also has potential as a ...gut microbiome modulator, although its applications in final formulations represent a challenge due to its low solubility, both in water and in organic solvents. This work addresses this problem by functionalizing naringin through enzymatic acylation.
The enzymatic acylation catalyzed by the lipase Novozym® 435 and using acyl donors of different chain lengths, acetate (C2), propionate (C3), and laurate (C12), yielded in conversions of 95% at 24 h and 100% at 48 h, generating a monoacylated product. Both the aqueous and solvent solubility of acylated naringin products were improved while maintaining or even increasing their antioxidant activity.
This acylation process significantly enhanced both the water and solvent solubility of the acylated naringin products while preserving or even enhancing their antioxidant activity. In addition to the gut-modulating properties of flavonoids, acylating them with short- and medium-chain fatty acids could enhance their potential applications in the emerging field of research dedicated to understanding and modulating gut health.
How to cite: Gutiérrez-Navarro E, Padilla-de la Rosa JD, Macías A, et al. Enzymatically acylated naringin with gut modulation potential. Electron J Biotechnol 2024; 68. https://doi.org/10.1016/j.ejbt.2023.12.003.
Subchronic oxidative stress and inflammation are being increasingly implicated in the pathogenesis of numerous diseases, such as Alzheimer's or Parkinson's disease. This study was designed to ...evaluate the potential protective role of α7 nicotinic receptor activation in an in vitro model of neurodegeneration based on subchronic oxidative stress. Rat organotypic hippocampal cultures (OHCs) were exposed for 4 days to low concentration of lipopolysaccharide (LPS) and the complex III mitochondrial blocker, antimycin-A. Antimycin-A (0.1μM) and lipopolysaccharide (1ng/ml) caused low neurotoxicity on their own, measured as propidium iodide fluorescence in CA1 and CA3 regions. However, their combination (LPS/AA) caused a greater detrimental effect, in addition to mitochondrial depolarization, overproduction of reactive oxygen species (ROS) and Nox4 overexpression. Antimycin-A per se increased ROS and mitochondrial depolarization, although these effects were significantly higher when combined with LPS. More interesting was the finding that exposure of OHCs to the combination of LPS/AA triggered aberrant protein aggregation, measured as thioflavin S immunofluorescence. The α7 nicotinic receptor agonist, PNU282987, prevented the neurotoxicity and the pathological hallmarks observed in the LPS/AA subchronic toxicity model (oxidative stress and protein aggregates); these effects were blocked by α-bungarotoxin and tin protoporphyrin, indicating the participation of α7 nAChRs and heme-oxygenase I induction. In conclusion, subchronic exposure of OHCs to low concentration of antimycin-A plus LPS reproduced pathological features of neurodegenerative disorders. α7 nAChR activation ameliorated these alterations by a mechanism involving heme-oxygenase I induction.
Recent human genetic studies suggest that cells of the innate immune system have a primary role in the pathogenesis of neurodegenerative diseases. However, the results from these studies often do not ...elucidate how the genetic variants affect the biology of these cells to modulate disease risk. Here, we applied a tensor decomposition method to uncover disease associated gene networks linked to distal genetic variation in stimulated human monocyte and macrophage gene expression profiles. We report robust evidence that some disease associated genetic variants affect the expression of multiple genes in trans. These include a Parkinson's disease locus influencing the expression of genes mediated by a protease that controls lysosomal function, and Alzheimer's disease loci influencing the expression of genes involved in type 1 interferon signaling, myeloid phagocytosis, and complement cascade pathways. Overall, we uncover gene networks in induced innate immune cells linked to disease associated genetic variants, which may help elucidate the underlying biology of disease.
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