Role of Immunity and Inflammation in the Pathophysiology of Neurodegenerative Diseases

Masitinib as a neuroprotective agent: a scoping review of preclinical and clinical evidence

OBJECTIVES

Masitinib, originally developed as a tyrosine kinase inhibitor for cancer treatment, has shown potential neuroprotective effects in various neurological disorders by modulating key pathways implicated in neurodegeneration. This scoping review aimed to summarize the current evidence of masitinib's neuroprotective activities from preclinical to clinical studies.

METHODS

This scoping review was conducted following the guidelines described by Arksey and O'Malley and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The inclusion criteria covered all original studies reporting on the neuroprotective effects of masitinib, including clinical studies, animal studies, and in vitro studies.

RESULTS

A total of 16 studies met the inclusion criteria and were included in the review. These comprised five randomized controlled trials (RCTs), one post-hoc analysis study, one case report, and nine animal studies. The RCTs focused on Alzheimer's disease (two studies), multiple sclerosis (two studies), and amyotrophic lateral sclerosis (one study). Across all included studies, masitinib consistently demonstrated neuroprotective properties. However, the majority of RCTs reported concerns regarding the safety profile of masitinib. Preclinical studies revealed the neuroprotective mechanisms of masitinib, which include inhibition of certain kinases interfering with cell proliferation and survival, reduction of neuroinflammation, and exhibition of antioxidant activity.

CONCLUSION

The current evidence suggests a promising therapeutic benefit of masitinib in neurodegenerative diseases. However, further research is necessary to validate and expand upon these findings, particularly regarding the precise mechanisms through which masitinib exerts its therapeutic effects. Future studies should also focus on addressing the safety concerns associated with masitinib use.

Understanding the Role of Galectin-1 in Heart Failure: A Comprehensive Narrative Review

Heart failure (HF) is the fastest-growing cardiovascular condition worldwide. The immune system may play a role in the development of HF since this condition is associated with elevated pro-inflammatory cytokine levels. HF is a life-threatening disease, and there is an increasing demand for diagnostic biomarkers, prognostic factors, and therapeutic agents that can help treat it. Galectin-1 (Gal-1) is the prototype galectin of the lectin family. Multiple signal transduction pathways are regulated by Ras proteins, which act as a molecular switch in cells. Gal-1 regulates T and B cell activation, differentiation, and survival. Gal-1 has been linked to inflammation. Activated T cells produce Gal-1 through an autocrine apoptotic mechanism involving MEK1/ERK and p38 MAPK. In the cardiovascular system, atherosclerosis is facilitated by Gal-1. Heart disease, myocardial infarction, hypertension, and stroke can be caused by atherosclerotic plaque. HF and heart hypertrophy are caused by decreased cardiac L-type Ca2+ channel activity. Deregulation of Gal-1 and CaV1.2 in pathological cardiac hypertrophy suggests a possible target for anti-hypertrophic therapy. Rat hypertrophic cardiomyocytes express Gal-1 and CaV1.2 channels simultaneously. It has been reported that diastolic dysfunction (DD) is associated with elevated Gal-1 levels. The high Gal-1 level in subjects led to the lowest cumulative survival as a composite endpoint. Incidences of HF, DD, and serum Gal-1 levels correlated significantly. The ejection fraction was negatively correlated with Gal-1 and CRP concentrations. Based on two different approaches in mice and humans, Gal-1 was identified as a potential mediator of HF.

Peripheral immune function and Alzheimer's disease: a living systematic review and critical appraisal

BACKGROUND

A growing body of literature examines the relationship between peripheral immune function and Alzheimer's Disease (AD) in human populations. Our living systematic review summarizes the characteristics and findings of these studies, appraises their quality, and formulates recommendations for future research.

METHODS

We searched the electronic databases PubMed, PsycINFO, and Web of Science, and reviewed references of previous reviews and meta-analyses to identify human studies examining the relationship between any peripheral immune biomarkers and AD up to September 7th, 2023. We examined patterns of reported statistical associations (positive, negative, and null) between each biomarker and AD across studies. Evidence for each biomarker was categorized into four groups based on the proportion of studies reporting different associations: corroborating a positive association with AD, a negative association, a null association, and presenting contradictory findings. A modified Newcastle-Ottawa scale (NOS) was employed to assess the quality of the included studies.

FINDINGS

In total, 286 studies were included in this review. The majority were cross-sectional (n = 245, 85.7%) and hospital-based (n = 248, 86.7%), examining relationships between 187 different peripheral immune biomarkers and AD. Cytokines were the most frequently studied group of peripheral immune biomarkers. Evidence supported a positive association with AD for six biomarkers, including IL-6, IL-1β, IFN-γ, ACT, IL-18, and IL-12, and a negative association for two biomarkers, including lymphocytes and IL-6R. Only a small proportion of included studies (n = 22, 7.7%) were deemed to be of high quality based on quality assessment.

INTERPRETATION

Existing research on peripheral immune function and AD exhibits substantial methodological variations and limitations, with a notable lack of longitudinal, population-based studies investigating a broad range of biomarkers with prospective AD outcomes. The extent and manner in which peripheral immune function can contribute to AD pathophysiology remain open questions. Given the biomarkers that we identified to be associated with AD, we posit that targeting peripheral immune dysregulation may present a promising intervention point to reduce the burden of AD.

Mesenchymal stem cells (MSCs) and MSC-derived exosomes in animal models of central nervous system diseases: Targeting the NLRP3 inflammasome

The NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) inflammasome is a multimeric protein complex that is engaged in the innate immune system and plays a vital role in inflammatory reactions. Activation of the NLRP3 inflammasome and subsequent release of proinflammatory cytokines can be triggered by microbial infection or cellular injury. The NLRP3 inflammasome has been implicated in the pathogenesis of many disorders affecting the central nervous system (CNS), ranging from stroke, traumatic brain injury, and spinal cord injury to Alzheimer's disease, Parkinson's disease, epilepsy, multiple sclerosis, and depression. Furthermore, emerging evidence has suggested that mesenchymal stem cells (MSCs) and their exosomes may modulate NLRP3 inflammasome activation in a way that might be promising for the therapeutic management of CNS diseases. In the present review, particular focus is placed on highlighting and discussing recent scientific evidence regarding the regulatory effects of MSC-based therapies on the NLRP3 inflammasome activation and their potential to counteract proinflammatory responses and pyroptotic cell death in the CNS, thereby achieving neuroprotective impacts and improvement in behavioral impairments.

Biogenic silver NPs alleviate LPS-induced neuroinflammation in a human fetal brain-derived cell line: Molecular switch to the M2 phenotype, modulation of TLR4/MyD88 and Nrf2/HO-1 signaling pathways, and molecular docking analysis

Silver nanoparticles (AgNPs) have inconsistent findings against inflammation. Although a wealth of literature on the beneficial effects of green-synthesized AgNPs has been published, a detailed mechanistic study of green AgNPs on the protective effects against lipopolysaccharide (LPS)-induced neuroinflammation using human microglial cells (HMC3) has not yet been reported. For the first time, we studied the inhibitory effect of biogenic AgNPs on inflammation and oxidative stress induced by LPS in HMC3 cells. X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and transmission electron microscopy were used to characterize AgNPs produced from honeyberry. Co-treatment with AgNPs significantly reduced mRNA expressions of inflammatory molecules such as interleukin (IL)-6 and tumor necrosis factor-α, while increasing the expressions of anti-inflammatory markers such as IL-10 and transforming growth factor (TGF)-β. HMC3 cells were also switched from M1 to M2, as shown by lower expression of M1 markers such as cluster of differentiation (CD)80, CD86, and CD68 and higher expression of M2 markers such as CD206, CD163, and triggering receptors expressed on myeloid cells (TREM2). Furthermore, AgNPs inhibited LPS-induced toll-like receptor (TLR)4 signaling, as evidenced by decreased expression of myeloid differentiation factor 88 (MyD88) and TLR4. In addition, AgNPs reduced the production of reactive oxygen species (ROS) and enhanced the expression of nuclear factor-E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), while decreasing the expression of inducible nitric oxide synthase. The docking score of the honeyberry phytoconstituents ranged from -14.93 to - 4.28 KJ/mol. In conclusion, biogenic AgNPs protect against neuroinflammation and oxidative stress by targeting TLR4/MyD88 and Nrf2/HO-1 signaling pathways in a LPS-induced in vitro model. Biogenic AgNPs could be utilized as potential nanomedicine against LPS-induced inflammatory disorders.

Longitudinal body weight dynamics in relation to cognitive decline over two decades: A prospective cohort study

OBJECTIVE

The aim of this study was to investigate the associations of body weight change (BWC) and body weight variability (BWV) with changes in cognitive function.

METHODS

In 10,340 Health and Retirement Study participants (mean age: 68.0 years), body weight was reported biennially from 1993/1994 to 2016, and cognitive function was measured biennially from 1998 to 2016. We calculated BWC and BWV as the slope and root-mean-square error by regressing body weight on time for each individual. BWC was categorized by quintiles (Q): stable weight (Q2 to Q4), weight loss (Q1), and weight gain (Q5). BWV was categorized by tertiles. We used linear mixed regression models to assess associations with cognitive change.

RESULTS

Compared with stable weight (median: 0 kg/y), weight loss (median: -1.3 kg/y) predicted faster cognitive decline as demonstrated by mean difference of -0.023 (95% CI: -0.027 to -0.019) in cognitive change z score per year, whereas weight gain (median: 1 kg/y) was related to slower cognitive decline (β = 0.006; 95% CI: 0.003 to 0.009). Larger BWV was also associated with faster cognitive decline (β comparing the top with bottom tertile = -0.003; 95% CI: -0.006 to -0.0002). Similar associations were observed for episodic and working memory.

CONCLUSIONS

Weight loss and large BWV over a long time independently predicted faster cognitive decline in middle-aged and older adults, underscoring the importance of long-term dynamic body weight monitoring.

Neurodegenerative Diseases: Implications of Environmental and Climatic Influences on Neurotransmitters and Neuronal Hormones Activities

Neurodegenerative and neuronal-related diseases are major public health concerns. Human vulnerability to neurodegenerative diseases (NDDs) increases with age. Neuronal hormones and neurotransmitters are major determinant factors regulating brain structure and functions. The implications of environmental and climatic changes emerged recently as influence factors on numerous diseases. However, the complex interaction of neurotransmitters and neuronal hormones and their depletion under environmental and climatic influences on NDDs are not well established in the literature. In this review, we aim to explore the connection between the environmental and climatic factors to NDDs and to highlight the available and potential therapeutic interventions that could use to improve the quality of life and reduce susceptibility to NDDs.

Bioinformatics-Guided Identification of Ethyl Acetate Extract of Citri Reticulatae Pericarpium as a Functional Food Ingredient with Anti-Inflammatory Potential

Citri Reticulatae Pericarpium (CRP) is one of the most commonly used food supplements and folk medicines worldwide, and possesses cardiovascular, digestive, and respiratory protective effects partially through its antioxidant and anti-inflammatory functions. The unique aromatic flavor and mild side effects make CRP a promising candidate for the development of anti-inflammatory functional food. However, recent studies show that the crude alcoholic extract and some isolated compounds of CRP show compromised anti-inflammatory activity, which became the main factor hindering its further development. To identify the bioactive compounds with anti-inflammatory potential, and improve the anti-inflammatory effects of the extract, a bioinformatics-guided extraction protocol was employed in this study. The potential bioactive candidates were identified by combing network pharmacology analysis, molecular docking, principal components analysis, k-means clustering, and in vitro testing of reference compounds. Our results demonstrated that 66 compounds in CRP could be grouped into four clusters according to their docking score profile against 24 receptors, while the cluster containing flavonoids and phenols might possess a more promising anti-inflammatory function. In addition, in vitro anti-inflammatory tests of the seven reference compounds demonstrated that hesperitin, naringenin, and gardenin B, which were grouped into a cluster containing flavonoids and phenols, significantly decreased LPS-induced NO, TNF-α, and IL-6 production of macrophages. While the compounds outside of that cluster, such as neohesperidin, naringin, hesperidin, and sinensetin showed little effect on alleviating LPS-induced NO and proinflammatory cytokine production. Based on the chemical properties of selected compounds, ethyl acetate (EtOAc) was selected as the solvent for extraction, because of its promising solubility of flavonoids and phenols. Furthermore, the ethanol alcoholic extract was used as a reference. The chemical profiling of EtOAc and crude alcoholic extract by HPLC/MS/MS also demonstrated the decreased abundance of flavonoid glycosides in EtOAc extract but increased abundance of phenols, phenolic acid, and aglycones. In accordance with the prediction, the EtOAc extract of CRP, but not the crude alcoholic extract, significantly decreased the NO, IL-6, and TNF-α production. Taken together, the results suggested selective extraction of phenols and flavonoids rich extract was able to increase the anti-inflammatory potential of CRP partially because of the synergistic effects between flavonoids, phenols, and enriched polymethoxyflavones. Our study might pave the road for the development of ethyl acetate extract of CRP as a novel functional food with anti-inflammatory function.

Improving cognitive function through high-intensity interval training in breast cancer patients undergoing chemotherapy – the CLARITY Trial: Protocol for a randomized study. (Preprint)

BACKGROUND

More than 75% of patients with breast cancer treated with chemotherapy experience cognitive impairments (eg, memory and attention problems), commonly known as chemo-brain. Exercise, especially aerobic high-intensity interval training (HIIT), is associated with better cognitive function in healthy populations. However, clinical trials testing the impact of exercise interventions on chemotherapy-induced cognitive decline in patients with cancer are lacking, and the mechanisms through which exercise could improve cognitive function are unclear.

OBJECTIVE

The objective of the Improving Cognitive Function Through High-Intensity Interval Training in Breast Cancer Patients Undergoing Chemotherapy trial is to examine the effects of HIIT on cognitive function in patients with breast cancer undergoing chemotherapy.

METHODS

This 2-arm, single-center, pilot randomized controlled trial will randomize 50 patients with breast cancer undergoing chemotherapy to HIIT or attention control. The HIIT group will perform a supervised 16-week, thrice-weekly intervention, with each session including a 5-minute warm-up at 10% maximal power output (POmax), 10 sets of alternating 1-minute high-intensity (90% POmax) and 1-minute recovery (10% POmax) intervals, and a 5-minute cooldown (10% POmax). The attention control group will receive a stretching program with no exercise components and be asked to maintain their exercise levels for 16 weeks. The primary outcomes of the study are executive function and memory measured using the National Institutes of Health toolbox and resting-state connectivity and diffusion tensor imaging microstructure evaluated using magnetic resonance imaging. The secondary and tertiary outcomes include cardiorespiratory fitness, body composition, physical fitness, and psychosocial health. The study has been approved by the institutional review board of the Dana-Farber Cancer Institute (20-222).

RESULTS

The trial was funded in January 2019, with recruitment started in June 2021. As of May 2022, a total of 4 patients have consented and been randomized (n=2, 50% to exercise; n=1, 25% to control; and n=1, 25% nonrandomized). Trial completion is expected in January 2024.

CONCLUSIONS

This first-of-its-kind study incorporates a novel exercise intervention (ie, HIIT) and comprehensive cognitive measures. If positive, our findings will establish the pilot efficacy of HIIT on chemotherapy-induced cognitive function in patients with breast cancer, providing the foundation for future larger phase-II and phase-III trials to confirm the findings and potentially establish HIIT as a standard of care for women undergoing chemotherapy for breast cancer.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04724499; https://clinicaltrials.gov/ct2/show/NCT04724499.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/39740.

The Role of Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RA) in Diabetes-Related Neurodegenerative Diseases

Recent clinical guidelines have emphasized the importance of screening for cognitive impairment in older adults with diabetes, however, there is still a lack of understanding about the drug therapy. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) are widely used in the treatment of type 2 diabetes and potential applications may include the treatment of obesity as well as the adjunctive treatment of type 1 diabetes mellitus in combination with insulin. Growing evidence suggests that GLP-1 RA has the potential to treat neurodegenerative diseases, particularly in diabetes-related Alzheimer’s disease (AD) and Parkinson’s disease (PD). Here, we review the molecular mechanisms of the neuroprotective effects of GLP-1 RA in diabetes-related degenerative diseases, including AD and PD, and their potential effects.

A New Insight into an Alternative Therapeutic Approach to Restore Redox Homeostasis and Functional Mitochondria in Neurodegenerative Diseases

Neurodegenerative diseases are accompanied by oxidative stress and mitochondrial dysfunction, leading to a progressive loss of neuronal cells, formation of protein aggregates, and a decrease in cognitive or motor functions. Mitochondrial dysfunction occurs at the early stage of neurodegenerative diseases. Protein aggregates containing oxidatively damaged biomolecules and other misfolded proteins and neuroinflammation have been identified in animal models and patients with neurodegenerative diseases. A variety of neurodegenerative diseases commonly exhibits decreased activity of antioxidant enzymes, lower amounts of antioxidants, and altered cellular signalling. Although several molecules have been approved clinically, there is no known cure for neurodegenerative diseases, though some drugs are focused on improving mitochondrial function. Mitochondrial dysfunction is caused by oxidative damage and impaired cellular signalling, including that of peroxisome proliferator-activated receptor gamma coactivator 1α. Mitochondrial function can also be modulated by mitochondrial biogenesis and the mitochondrial fusion/fission cycle. Mitochondrial biogenesis is regulated mainly by sirtuin 1, NAD⁺, AMP-activated protein kinase, mammalian target of rapamycin, and peroxisome proliferator-activated receptor γ. Altered mitochondrial dynamics, such as increased fission proteins and decreased fusion products, are shown in neurodegenerative diseases. Due to the restrictions of a target-based approach, a phenotype-based approach has been performed to find novel proteins or pathways. Alternatively, plasma membrane redox enzymes improve mitochondrial function without the further production of reactive oxygen species. In addition, inducers of antioxidant response elements can be useful to induce a series of detoxifying enzymes. Thus, redox homeostasis and metabolic regulation can be important therapeutic targets for delaying the progression of neurodegenerative diseases.

Immune function, cortisol, and cognitive decline & dementia in an aging latino population

BACKGROUND

The etiology of dementias and cognitive decline remain largely unknown. It is widely accepted that inflammation in the central nervous system plays a critical role in the pathogenesis of dementia. However, less is known about the role of the peripheral immune system and interactions with cortisol, though evidence suggests that these, too, may play a role.

METHODS

Using data from 1337 participants aged 60+ years from the Sacramento Area Latino Study of Aging (observational cohort) we investigated variation in trajectories of cognitive decline by pathogen IgG and cytokine levels. Linear mixed effects models were used to examine the association between baseline Interleukin (IL)-6, C-reactive protein, tumor necrosis factor (TNF)-α, and five persistent pathogens' IgG response and trajectories of cognition over 10 years, and to examine interactions between immune biomarkers and cortisol. Stratified cumulative incidence functions were used to assess the relation between biomarkers and incident dementia. Inverse probability weights accounted for loss-to-follow-up and confounding.

RESULTS

IL-6, TNF-α, and CMV IgG were statistically significantly associated with a higher log of Modified Mini-Mental State Examination errors (IL-6, β=0.0935 (95%CI: 0.055, 0.13), TNF-alpha β= 0.0944 (95%CI: 0.032, 0.157), and CMV, β= 0.0409 (95%CI: 0.013, 0.069)). Furthermore, cortisol interacted with HSV-1 and IL-6, and CRP for both cross-sectional cognitive function and rate of decline. No statistically significant relationship was detected between biomarkers and incidence of dementia.

CONCLUSIONS

These findings support the theory that the peripheral immune system may play a role in cognitive decline but not incident dementia. Furthermore, they identify specific markers amenable for intervention for slowing decline.

Neuroprotective effects of oleuropein: Recent developments and contemporary research

Neurological disorders are increasing at a faster pace due to oxidative stress, protein aggregation, excitotoxicity, and neuroinflammation. It is reported that the Mediterranean diet including olives as a major dietary component prevents and ameliorates neurological anomalies. Oleuropein is the major bioactive component in different parts of the Olive (Olea europaea L.) tree. Several mechanisms have been reported for the neuroprotective role of oleuropein including induction of apoptosis and autophagy, enhancing the antioxidant pool of the cerebral region, decreasing the unnecessary release of proinflammatory cytokines and chemokines by deactivating the microglia cells and astrocytes thus preventing the occurrence of neuroinflammation. Regular intake of oleuropein seems to be correlated with decreased risks of neural disorders including Alzheimer's, Parkinson's, strokes, depression, anxiety, epilepsy, and others. This review majorly discusses the chemistry, biosynthesis, and metabolism of oleuropein along with an updated vision of its neuroprotective role in counteracting the acute and chronic neurodegenerative and neuropsychiatric disorders. Moreover, mechanisms by which oleuropein may prevent neurodegeneration are reviewed. PRACTICAL APPLICATION: Neurological disorders are negatively affecting the health and life quality of individuals around the globe. Although various medicinal solutions are available to tackle such ailments, none has proven to fully cure and being deprived of side effects. In this respect, the prevention of such disorders using natural remedies may be an effective strategy to overcome the incidence of the increasing cases. Furthermore, the natural compounds provide a safer alternative to pharmaceutical drugs. Hence, oleuropein from olive tree products is found to be efficacious against neurological disorders. This review provides an updated insight on the positive effects of oleuropein against neurodegenerative and neuropsychiatric disorders. The diet practitioners and nutraceutical companies may benefit from the provided information to design and develop strategies to improve the mental health of suffering individuals.

NLRP3 inflammasome activation mediates sleep deprivation-induced pyroptosis in mice

Background

Sleep deprivation (SD) has many deleterious health effects, including cognitive decline, work ability decline, inadequate alertness, etc. Neuroinflammation plays an important role in sleep deprivation. However, the underlying mechanism is still unclear.

Methods

In the present study, we detected the activation of microglia and apoptosis of nerve cells in sleep deprivation (SD) mice model using IHC, HE staining and TUNEL apoptosis assay. RT-PCR array data were used to detect the expression of inflammatory bodies in hippocampal CA1 region after sleep deprivation, to explore how NLRP3 inflammasome regulates neuronal apoptosis and how specific signaling pathways are involved in SD-induced activation of NLRP3/pyrosis axis.

Results

We found the number of microglia significantly increased in SD mice, while this effect was blocked by sleep recovery. RT-PCR array data suggested that NLRP3 inflammasome, but not other inflammasomes, was obviously increased in hippocampus CA1 region after sleep deprivation. Mechanistically, we found that NLRP3 mediated the pyroptosis of neurocyte through GSDMD-dependent way , and P38 and ERK-MAPK signaling pathway is involved in SD-induced activation of NLRP3/pyroptosis axis. All these results suggested that MAPK/NLRP3 axis mediated SD-induced pyroptosis.

Conclusion

NLRP3 plays an important role in SD-induced neuroinflammation. Thus, NLRP3 inflammasome is expected to be a potential therapeutic target for SD-induced neuroinflammation.

Association Between Immune Response to Cytomegalovirus and Cognition in the Health and Retirement Study

Chronic infections and the subsequent immune response have recently been shown to be risk factors for cognitive decline and Alzheimer disease and related dementias (ADRD). While some studies have shown an association between cytomegalovirus (CMV), a chronic and highly prevalent infection, and cognition and/or ADRD, these studies have been limited by nonrepresentative and small samples. Using 2016 data on 5,617 adults aged 65 years or more from the Health and Retirement Study, we investigated the cross-sectional associations of both CMV serostatus and immunoglobulin G (IgG) antibody response with cognitive function using linear regression models adjusting for age, sex, race/ethnicity, and educational attainment. We further investigated potential effect-measure modification by educational attainment. Overall, both CMV seropositivity and higher IgG antibody response were associated with lower cognitive function, though the relationship was not statistically significant in adjusted models. Among participants with less than a high school diploma, CMV seropositivity and being in the first tertile of IgG response, relative to seronegative persons, were associated with lower scores on the Telephone Interview for Cognitive Status (-0.56 points (95% confidence interval: -1.63, 0.52) and -0.89 points (95% confidence interval: -2.07, 0.29), respectively), and the relationship was attenuated among those with higher education. Our results suggest that CMV may be a risk factor for cognitive impairment, particularly among persons with fewer educational resources.

Elucidating the Multi-Targeted Role of Nutraceuticals: A Complementary Therapy to Starve Neurodegenerative Diseases

The mechanisms underlying multifactorial diseases are always complex and challenging. Neurodegenerative disorders (NDs) are common around the globe, posing a critical healthcare issue and financial burden to the country. However, integrative evidence implies some common shared mechanisms and pathways in NDs, which include mitochondrial dysfunction, neuroinflammation, oxidative stress, intracellular calcium overload, protein aggregates, oxidative stress (OS), and neuronal destruction in specific regions of the brain, owing to multifaceted pathologies. The co-existence of these multiple pathways often limits the advantages of available therapies. The nutraceutical-based approach has opened the doors to target these common multifaceted pathways in a slow and more physiological manner to starve the NDs. Peer-reviewed articles were searched via MEDLINE and PubMed published to date for in-depth research and database collection. Considered to be complementary therapy with current clinical management and common drug therapy, the intake of nutraceuticals is considered safe to target multiple mechanisms of action in NDs. The current review summarizes the popular nutraceuticals showing different effects (anti-inflammatory, antioxidant, neuro-protectant, mitochondrial homeostasis, neurogenesis promotion, and autophagy regulation) on vital molecular mechanisms involved in NDs, which can be considered as complementary therapy to first-line treatment. Moreover, owing to its natural source, lower toxicity, therapeutic interventions, biocompatibility, potential nutritional effects, and presence of various anti-oxidative and neuroprotective constituents, the nutraceuticals serve as an attractive option to tackle NDs.

Antibodies Against the NH2-Terminus of the GluA Subunits Affect the AMPA-Evoked Releasing Activity: The Role of Complement

Antibodies recognizing the amino-terminal domain of receptor subunit proteins modify the receptor efficiency to controlling transmitter release in isolated nerve endings (e.g., synaptosomes) indirectly confirming their presence in these particles but also allowing to speculate on their subunit composition. Western blot analysis and confocal microscopy unveiled the presence of the GluA1, GluA2, GluA3, and GluA4 receptor subunits in cortical synaptosomes. Functional studies confirmed the presence of presynaptic release-regulating AMPA autoreceptors in these terminals, whose activation releases [3H]D-aspartate ([3H]D-Asp, here used as a marker of glutamate) in a NBQX-dependent manner. The AMPA autoreceptors traffic in a constitutive manner, since entrapping synaptosomes with the pep2-SVKI peptide (which interferes with the GluA2-GRIP1/PICK1 interaction) amplified the AMPA-evoked releasing activity, while the inactive pep2-SVKE peptide was devoid of activity. Incubation of synaptosomes with antibodies recognizing the NH2 terminus of the GluA2 and the GluA3 subunits increased, although to a different extent, the GluA2 and 3 densities in synaptosomal membranes, also amplifying the AMPA-evoked glutamate release in a NBQX-dependent fashion. We then analyzed the releasing activity of complement (1:300) from both treated and untreated synaptosomes and found that the complement-induced overflow occurred in a DL-t-BOA-sensitive, NBQX-insensitive fashion. We hypothesized that anti-GluA/GluA complexes in neuronal membranes could trigger the classic pathway of activation of the complement, modifying its releasing activity. Accordingly, the complement-evoked release of [3H]D-Asp from antiGluA2 and anti-GluA3 antibody treated synaptosomes was significantly increased when compared to untreated terminals and facilitation was prevented by omitting the C1q component of the immunocomplex. Antibodies recognizing the NH2 terminus of the GluA1 or the GluA4 subunits failed to affect both the AMPA and the complement-evoked tritium overflow. Our results suggest the presence of GluA2/GluA3-containing release-regulating AMPA autoreceptors in cortical synaptosomes. Incubation of synaptosomes with commercial anti-GluA2 or anti-GluA3 antibodies amplifies the AMPA-evoked exocytosis of glutamate through a complement-independent pathway, involving an excessive insertion of AMPA autoreceptors in plasma membranes but also affects the complement-dependent releasing activity, by promoting the classic pathway of activation of the immunocomplex. Both events could be relevant to the development of autoimmune diseases typified by an overproduction of anti-GluA subunits.

Anti-inflammatory effect of rosmarinic acid isolated from Blechnum brasiliense in adult zebrafish brain

Neuroinflammation has been associated to neurodegenerative disease development, with evidence suggesting that high levels of proinflammatory cytokines promote neuronal dysfunction and death. Therefore, it is necessary to study new compounds that may be used as adjuvant treatments of neurodegenerative diseases by attenuating the inflammatory response in the central nervous system (CNS). The aim of this study was to utilize the lipopolysaccharide (LPS) induction model of neuroinflammation to evaluate the modulation of inflammation by rosmarinic acid (RA) isolated from Blechnum brasiliense in adult zebrafish. First, we investigated the toxicity and antioxidant properties of fractionated B. brasiliense extract (ethyl acetate fraction- EAF) and the isolated RA in zebrafish embryos. Next, we developed a model of neuroinflammation induction by intraperitoneal (i.p.) injection of LPS to observe the RA modulation of proinflammatory cytokines. The median lethal concentration (LC50) calculated was 185.2 ± 1.24 μg/mL for the ethyl acetate fraction (EAF) and 296.0 ± 1.27 μM for RA. The EAF showed free radical inhibition ranging from 23.09% to 63.44% at concentrations of 10-250 μg/mL. The RA presented a concentration-dependent response ranging from 18.24% to 47.63% at 10-250 μM. Furthermore, the RA reduced LPS induction of TNF-α and IL-1β levels, with the greatest effect observed 6 h after LPS administration. Thus, the data suggested an anti-inflammatory effect of RA isolated from B. brasiliense and reinforced the utility of the new model of neuroinflammation to test the possible neuroprotective effects of novel drugs or compounds.

Dexmedetomidine Alleviates LPS-Induced Neuronal Dysfunction by Modulating the AKT/GSK-3β/CRMP-2 Pathway in Hippocampal Neurons

OBJECTIVE

Dexmedetomidine, an α2-adrenergic receptor agonist, mitigates cognitive dysfunction in elderly patients after surgery with general anesthesia. However, the underlying mechanism by which dexmedetomidine reduces cognitive dysfunction remains to be fully elucidated. The aim of this study was to investigate the effects of dexmedetomidine on lipopolysaccharide (LPS)-induced neuronal dysfunction in cultured hippocampal neurons.

METHODS

LPS, in the presence and absence of dexmedetomidine, was applied to cultured hippocampal neurons to mimic post-surgical inflammation. Neuronal morphology, including neurite outgrowth and synaptic transmission, was observed, and miniature excitatory postsynaptic currents were recorded by electrophysiological patch-clamp.

RESULTS

LPS significantly impaired neurite outgrowth in hippocampal neurons in a concentration- and time-dependent manner, which was reversed by dexmedetomidine treatment. Electrophysiological patch-clamp results showed that LPS induced synaptic transmission dysfunction, which was restored after dexmedetomidine addition. Furthermore, Western blotting assays showed that LPS suppressed the AKT/GSK-3β/CRMP-2 signaling pathway and dexmedetomidine countered the inhibitory effect of LPS by re-activating this pathway.

CONCLUSION

In general, dexmedetomidine protected against the effects of LPS-induced hippocampal neuron damage, including neurite outgrowth and synaptic transmission. Overall, dexmedetomidine modulated the AKT/GSK-3β/CRMP-2 signaling pathway to alleviate LPS-induced neurological dysfunction.

Peripheral Leukocytosis Predicts Cognitive Decline but Not Behavioral Disturbances: A Nationwide Study of Alzheimer's and Parkinson's Disease Patients

INTRODUCTION

Peripheral and central nervous system inflammation have been linked to the classic symptoms of Parkinson's disease (PD) and Alzheimer's disease (AD). However, it remains unclear whether the analysis of routine systemic inflammatory markers could represent a useful prediction tool to identify clinical subtypes in patients with Parkinson's and Alzheimer's at higher risk of dementia-associated symptoms, such as behavioral and psychological symptoms of dementia (BPSD).

METHODS

We performed a multivariate logistic regression using the 2016 and 2017 National Inpatient Sample with International Classification of Diseases 10th edition codes to assess if pro-inflammatory white blood cells (WBCs) anomalies correlate with dementia and BPSD in patients with these disorders.

RESULTS

We found that leukocytosis was the most common WBC inflammatory marker identified in 3.9% of Alzheimer's and 3.3% Parkinson's patients. Leukocytosis was also found to be an independent risk factor for Parkinson's dementia. Multivariate analysis of both cohorts showed that leukocytosis is significantly decreased in patients with BPSD compared to patients without BPSD.

CONCLUSIONS

These results suggest a link between leukocytosis and the pathophysiology of cognitive dysfunction in both PD and AD. A better understanding of the role of systemic neuroinflammation on these devastating neurodegenerative disorders may facilitate the development of cost-effective blood biomarkers for patient's early diagnosis and more accurate prognosis.

Vanillic Acid, a Bioactive Phenolic Compound, Counteracts LPS-Induced Neurotoxicity by Regulating c-Jun N-Terminal Kinase in Mouse Brain

The receptor for advanced glycation end products (RAGE), a pattern recognition receptor signaling event, has been associated with several human illnesses, including neurodegenerative diseases, particularly in Alzheimer’s disease (AD). Vanillic acid (V.A), a flavoring agent, is a benzoic acid derivative having a broad range of biological activities, including antioxidant, anti-inflammatory, and neuroprotective effects. However, the underlying molecular mechanisms of V.A in exerting neuroprotection are not well investigated. The present study aims to explore the neuroprotective effects of V.A against lipopolysaccharides (LPS)-induced neuroinflammation, amyloidogenesis, synaptic/memory dysfunction, and neurodegeneration in mice brain. Behavioral tests and biochemical and immunofluorescence assays were applied. Our results indicated increased expression of RAGE and its downstream phospho-c-Jun n-terminal kinase (p-JNK) in the LPS-alone treated group, which was significantly reduced in the V.A + LPS co-treated group. We also found that systemic administration of LPS-injection induced glial cells (microglia and astrocytes) activation and significantly increased expression level of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-KB) and secretion of proinflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin-1 β (IL1-β), and cyclooxygenase (COX-2). However, V.A + LPS co-treatment significantly inhibited the LPS-induced activation of glial cells and neuroinflammatory mediators. Moreover, we also noted that V.A treatment significantly attenuated LPS-induced increases in the expression of AD markers, such as β-site amyloid precursor protein (APP)–cleaving enzyme 1 (BACE1) and amyloid-β (Aβ). Furthermore, V.A treatment significantly reversed LPS-induced synaptic loss via enhancing the expression level of pre- and post-synaptic markers (PSD-95 and SYP), and improved memory performance in LPS-alone treated group. Taken together; we suggest that neuroprotective effects of V.A against LPS-induced neurotoxicity might be via inhibition of LPS/RAGE mediated JNK signaling pathway; and encourage future studies that V.A would be a potential neuroprotective and neurotherapeutic candidate in various neurological disorders.

Adiponectin/leptin ratio increases after a 12-week very low-carbohydrate, high-fat diet, and exercise training in healthy individuals: A non-randomized, parallel design study

This study aimed to investigate the effect of a 12-week very low-carbohydrate, high-fat (VLCHF) diet and exercise on biomarkers of inflammation in healthy individuals. Since the anti-inflammatory effects of a ketogenic diet have been established, we hypothesized that the VLCHF diet, along with exercise, would have an additional favorable effect on biomarkers of inflammation. Twenty-four healthy individuals were allocated to the VLCHF diet (VLCHF: N = 12, age 25.3 ± 2.0 years, body mass 66.7 ± 9.8 kg, fat mass 21.5% ± 4.9%), or habitual diet (HD: N = 12, age 23.9 ± 3.8 years, body mass 72.7 ± 15.0 kg, fat mass 23.4 ± 8.4 %) group. Biomarkers of inflammation (adiponectin, leptin, and high-sensitive interleukin-6 [hs-IL-6]) and substrate metabolism (glycated hemoglobin, fasting glucose, triacylglycerides, and cholesterol) were analyzed from blood at baseline and after 12 weeks. The adiponectin-leptin ratio significantly increased in the VLCHF group after the intervention period (ES [95% CL]: -0.90 [-0.96, -0.77], P ≤ .001, BF₁₀ = 22.15). The adiponectin-leptin ratio changes were associated with both a significant increase in adiponectin (-0.79 [-0.91, -0.54], P ≤ .001, BF₁₀ = 9.43) and a significant decrease in leptin (0.58 [0.19, 0.81], P = .014, BF₁₀ = 2.70). There was moderate evidence of changes in total cholesterol (-1.15 [-2.01, -0.27], P = .010, BF₁₀ = 5.20), and LDL cholesterol (-1.12 [-2.01, -0.21], P = .016, BF₁₀ = 4.56) in the VLCHF group. Body weight (kg) and fat mass (%) decreased in the VLCHF group by 5.4% and 14.9%, respectively. We found that in healthy young individuals, consuming a VLCHF diet while performing regular exercise over a 12-week period produced favorable changes in body weight and fat mass along with beneficial changes in serum adiponectin and leptin concentrations. These data support the use of a VLCHF diet strategy for the primary prevention of chronic diseases associated with systemic low-grade inflammation.

Inhibition of β-amyloid Aggregation of Ugni molinae Extracts

The β-amyloid peptide (1-42) is a molecule capable of aggregating into neurotoxic structures that have been implicated as potential etiological factors of Alzheimer's Disease. The aim of this study was to evaluate the inhibition of β-amyloid aggregation of ethyl acetate and ethanolic extracts obtained from Ugni molinae leaves on neurotoxic actions of β-amyloid aggregates. Chemical analyses were carried out with the extracts in order to determine their phenolic profile and its quantification. Both extracts showed a tendency to reduce neuronal deaths caused by β-amyloid. This tendency was inversely proportional to the evaluated concentrations. Moreover, the effect of EAE and ETE on β-amyloid aggregation was studied by fluorimetric T Thioflavin assay and transmission electronic microscopy (TEM); the extracts showed a modulation in the aggregation process. Partly, it is believed that these effects can be attributed to the polyphenolic compounds present in the extracts.

Role of Peripheral Immune Cells-Mediated Inflammation on the Process of Neurodegenerative Diseases

Neurodegenerative diseases are characterized by progressive loss of selectively vulnerable neuronal populations, which contrasts with selectively static loss of neurons due to toxic or metabolic disorders. The mechanisms underlying their progressive nature remain unknown. To date, a timely and well-controlled peripheral inflammatory reaction is verified to be essential for neurodegenerative diseases remission. The influence of peripheral inflammation on the central nervous system is closely related to immune cells activation in peripheral blood. The immune cells activation participated in the uncontrolled and prolonged inflammation that drives the chronic progression of neurodegenerative diseases. Thus, the dynamic modulation of this peripheral inflammatory reaction by interrupting the vicious cycle might become a disease-modifying therapeutic strategy for neurodegenerative diseases. This review focused on the role of peripheral immune cells on the pathological progression of neurodegenerative diseases.

The immune system on the TRAIL of Alzheimer's disease

Alzheimer's disease (AD) is the most common form of dementia, characterized by progressive degeneration and loss of neurons in specific regions of the central nervous system. Chronic activation of the immune cells resident in the brain, peripheral immune cell trafficking across the blood-brain barrier, and release of inflammatory and neurotoxic factors, appear critical contributors of the neuroinflammatory response that drives the progression of neurodegenerative processes in AD. As the neuro-immune network is impaired in course of AD, this review is aimed to point out the essential supportive role of innate and adaptive immune response either in normal brain as well as in brain recovery from injury. Since a fine-tuning of the immune response appears crucial to ensure proper nervous system functioning, we focused on the role of the TNF superfamily member, TNF-related apoptosis-inducing ligand (TRAIL), which modulates both the innate and adaptive immune response in the pathogenesis of several immunological disorders and, in particular, in AD-related neuroinflammation. We here summarized mounting evidence of potential involvement of TRAIL signaling in AD pathogenesis, with the aim to provide clearer insights about potential novel therapeutic approaches in AD.

Stimulus-Responsive Nanomedicines for Disease Diagnosis and Treatment

Stimulus-responsive drug delivery systems generally aim to release the active pharmaceutical ingredient (API) in response to specific conditions and have recently been explored for disease treatments. These approaches can also be extended to molecular imaging to report on disease diagnosis and management. The stimuli used for activation are based on differences between the environment of the diseased or targeted sites, and normal tissues. Endogenous stimuli include pH, redox reactions, enzymatic activity, temperature and others. Exogenous site-specific stimuli include the use of magnetic fields, light, ultrasound and others. These endogenous or exogenous stimuli lead to structural changes or cleavage of the cargo carrier, leading to release of the API. A wide variety of stimulus-responsive systems have been developed-responsive to both a single stimulus or multiple stimuli-and represent a theranostic tool for disease treatment. In this review, stimuli commonly used in the development of theranostic nanoplatforms are enumerated. An emphasis on chemical structure and property relationships is provided, aiming to focus on insights for the design of stimulus-responsive delivery systems. Several examples of theranostic applications of these stimulus-responsive nanomedicines are discussed.

Dietary natural products as epigenetic modifiers in aging-associated inflammation and disease

Covering: up to 2020Chronic, low-grade inflammation is linked to aging and has been termed "inflammaging". Inflammaging is considered a key contributor to the development of metabolic dysfunction and a broad spectrum of diseases or disorders including declines in brain and heart function. Genome-wide association studies (GWAS) coupled with epigenome-wide association studies (EWAS) have shown the importance of diet in the development of chronic and age-related diseases. Moreover, dietary interventions e.g. caloric restriction can attenuate inflammation to delay and/or prevent these diseases. Common themes in these studies entail the use of phytochemicals (plant-derived compounds) or the production of short chain fatty acids (SCFAs) as epigenetic modifiers of DNA and histone proteins. Epigenetic modifications are dynamically regulated and as such, serve as potential therapeutic targets for the treatment or prevention of age-related disease. In this review, we will focus on the role for natural products that include phytochemicals and short chain fatty acids (SCFAs) as regulators of these epigenetic adaptations. Specifically, we discuss regulators of methylation, acetylation and acylation, in the protection from chronic inflammation driven metabolic dysfunction and deterioration of neurocognitive and cardiac function.

Natural Products and Their Bioactive Compounds: Neuroprotective Potentials against Neurodegenerative Diseases

In recent years, natural products, which originate from plants, animals, and fungi, together with their bioactive compounds have been intensively explored and studied for their therapeutic potentials for various diseases such as cardiovascular, diabetes, hypertension, reproductive, cancer, and neurodegenerative diseases. Neurodegenerative diseases, including Alzheimer's disease, Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis are characterized by the progressive dysfunction and loss of neuronal structure and function that resulted in the neuronal cell death. Since the multifactorial pathological mechanisms are associated with neurodegeneration, targeting multiple mechanisms of actions and neuroprotection approach, which involves preventing cell death and restoring the function to damaged neurons, could be promising strategies for the prevention and therapeutic of neurodegenerative diseases. Natural products have emerged as potential neuroprotective agents for the treatment of neurodegenerative diseases. This review focused on the therapeutic potential of natural products and their bioactive compounds to exert a neuroprotective effect on the pathologies of neurodegenerative diseases.

Effects of a four-week very low-carbohydrate high-fat diet on biomarkers of inflammation: Non-randomised parallel-group study

BACKGROUND

It is commonly assumed that increased dietary fat and/or caloric excess induces chronic inflammatory processes, since the association between obesity and chronic adipose tissue with systemic inflammation has been shown previously. As far as we know, the reported health benefits of a VLCHF or ketogenic diet have not adequately involved an evaluation of biomarkers of inflammation.

AIM

This study investigated the effects of a four-week very low-carbohydrate high-fat (VLCHF) diet in healthy young individuals on biomarkers of inflammation.

METHODS

Eighteen moderately trained males (age 23.8 ± 2.1 years) were assigned to two groups. One group switched to a non-standardised VLCHF diet for four weeks, while the second group remained consuming their normal habitual diet (HD). Biomarkers of inflammation (adiponectin, leptin, resistin and interleukin-6) and substrate metabolism (fasting glucose and triacylglyceride concentrations) were analysed from blood at baseline and after four weeks.

RESULTS

There was moderate evidence for substantial changes in leptin serum concentrations in the VLCHF group, with small to large decreases compared to the HD group after four weeks (effect size = 0.78, 95% CI 0.42, 0.93, p = 0.008; Bayes Factor₁₀ = 5.70). No substantial between-group change differences over time were found across any other biomarkers.

CONCLUSIONS

A four-week period of consuming a VLCHF diet in healthy young men was not associated with any considerable changes in markers of inflammation but showed evidence for lowered serum leptin concentrations relative to the HD group.

Neurodegenerative diseases as proteinopathies-driven immune disorders

In the pathophysiology of neurodegenerative disorders, the role of misfolded protein deposition leading to neurodegeneration has been primarily discussed. In the last decade, however, it has been proposed a parallel involvement of innate immune activation, chronic inflammation and adaptive immunity in the neurodegeneration mechanisms triggered by proteinopathies. New insights in the neurodegenerative field strongly suggest a role for the immune system in the pathophysiology of neurodegenerative disorders. Therefore, the hypothesis underlining the modulation of the innate and the adaptive immune system in the events linked to brain deposition of misfolded proteins could open new perspectives in the setting of specific immunotherapeutic strategies for the treatment of neurodegenerative diseases. Therefore, we have reviewed the pathogenic hypothesis in neurodegenerative pathologies, underling the links between the deposition of misfolded protein mechanisms and the immune activation.

Hypothalamic transcriptome of tame and aggressive silver foxes (Vulpes vulpes) identifies gene expression differences shared across brain regions

The underlying neurological events accompanying dog domestication remain elusive. To reconstruct the domestication process in an experimental setting, silver foxes (Vulpes vulpes) have been deliberately bred for tame vs aggressive behaviors for more than 50 generations at the Institute for Cytology and Genetics in Novosibirsk, Russia. The hypothalamus is an essential part of the hypothalamic-pituitary-adrenal axis and regulates the fight-or-flight response, and thus, we hypothesized that selective breeding for tameness/aggressiveness has shaped the hypothalamic transcriptomic profile. RNA-seq analysis identified 70 differentially expressed genes (DEGs). Seven of these genes, DKKL1, FBLN7, NPL, PRIMPOL, PTGRN, SHCBP1L and SKIV2L, showed the same direction expression differences in the hypothalamus, basal forebrain and prefrontal cortex. The genes differentially expressed across the three tissues are involved in cell division, differentiation, adhesion and carbohydrate processing, suggesting an association of these processes with selective breeding. Additionally, 159 transcripts from the hypothalamus demonstrated differences in the abundance of alternative spliced forms between the tame and aggressive foxes. Weighted gene coexpression network analyses also suggested that gene modules in hypothalamus were significantly associated with tame vs aggressive behavior. Pathways associated with these modules include signal transduction, interleukin signaling, cytokine-cytokine receptor interaction and peptide ligand-binding receptors (eg, G-protein coupled receptor [GPCR] ligand binding). Current studies show the selection for tameness vs aggressiveness in foxes is associated with unique hypothalamic gene profiles partly shared with other brain regions and highlight DEGs involved in biological processes such as development, differentiation and immunological responses. The role of these processes in fox and dog domestication remains to be determined.

Genetic deletion of soluble epoxide hydrolase delays the progression of Alzheimer's disease

Background

Soluble epoxide hydrolase (sEH) is a bifunctional enzyme with COOH-terminal hydrolase and NH2-terminal lipid phosphatase activities. It is expressed in various cell types in the brain and is involved in the pathogenesis of inflammatory and neurodegenerative diseases. Alzheimer’s disease (AD) is a progressive neuroinflammatory and neurodegenerative disease. However, the pathological significance of sEH and underlying molecular mechanism in AD remain unclear.

Methods

To examine the role of sEH in pathogenesis of AD, we used wild-type (WT) mice, soluble epoxide hydrolase deficient (sEH^−/−) and two mouse models of AD, including amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (APP/PS1 Tg) and APP/PS1 Tg/sEH^−/− mice. Western blotting analysis and immunohistochemistry assay were performed to evaluate the protein expression. Locomotion, nesting building ability, Y-maze, and Morris water maze tests were conducted to study mouse behavior. The levels of interleukin (IL)-1β, IL-4, IL-6, and IL-10 and the activities of NF-κB and nuclear factor of activated T cells (NFAT) were measured by commercial assay kits. The quantitative protein level profiling in the brain lysate was analyzed using LC-MS/MS approaches.

Results

We demonstrated that the level of sEH was increased in the brain and predominantly appeared in hippocampal astrocytes of APP/PS1 Tg mice. Genetic ablation of sEH in APP/PS1 Tg mice delayed the progression of AD as evidenced by the alleviation in behavior outcomes and Aβ plaque deposition. In addition, loss of the function of sEH in APP/PS1 Tg mice increased astrogliosis and the production of astrocyte-derived anti-inflammatory cytokines including IL-1β, IL-4, and IL-10, as well as the activity of NF-kB and NFAT. Moreover, analysis of gene ontology in the AD brain revealed that important signaling pathways and processes related to AD pathogenesis such as translational regulation, oxidative stress, cytoskeleton reorganization, and small GTPase signal transduction were altered in APP/PS1 Tg/sEH^−/− mice compared with APP/PS1 Tg mice.

Conclusion

Our results suggest that sEH is a crucial regulator in the progression of AD and might be a potential therapeutic target for the treatment of AD.

Peroxisome Proliferator-Activated Receptor γ Agonist Rosiglitazone Protects Blood-Brain Barrier Integrity Following Diffuse Axonal Injury by Decreasing the Levels of Inflammatory Mediators Through a Caveolin-1-Dependent Pathway

Our early experiments confirmed that rosiglitazone (RSG), a peroxisome proliferator-activated receptor γ (PPARγ) agonist, had therapeutic potential for the treatment of diffuse axonal injury (DAI) by inhibiting the expression of amyloid-beta precursor protein and reducing the loss and abnormal phosphorylation of tau, but the underlying mechanisms were not fully defined. In this study, we aimed to investigate a possible role for PPARγ in the protection of blood-brain barrier (BBB) integrity in a rat model of DAI, and the underlying mechanisms. PPAR agonists and antagonists were intraperitoneally injected after DAI. Treatment with RSG ameliorated axonal injury, cell apoptosis, glia activation, and the release of inflammatory factors such as TNF-α, IL-1β, and IL-6. It also increased the expression of tight junction-associated proteins like ZO-1, claudin-5, and occludin-1, whereas the PPARγ antagonist GW9662 had the opposite effects. These effects were also studied in a BBB in vitro model, consisting of a monolayer of human microvascular endothelial cells (HBMECs) subjected to oxygen and glucose deprivation (OGD). Treatment with RSG ameliorated the loss of BBB integrity and the increased permeability induced by OGD by reducing the release of inflammatory factors and maintaining the expression of tight junction-associated proteins. Interestingly, caveolin-1 was found located mainly in endothelial cells, and RSG increased the expression of caveolin-1, which decreased following OGD. In contrast, caveolin-1 siRNA abrogated the protective effects of RSG in the in vitro BBB model. In conclusion, we provide evidence that PPARγ plays an important role in a series of processes associated with DAI, and that the PPARγ agonist RSG can protect BBB integrity by decreasing the levels of inflammatory mediators through a caveolin-1-dependent pathway.

Many Faces of TRIM Proteins on the Road from Pluripotency to Neurogenesis

Tripartite motif (TRIM) proteins participate in numerous biological processes. They are the key players in immune system and are involved in the oncogenesis. Moreover, TRIMs are the highly conserved regulators of developmental pathways in both vertebrates and invertebrates. In particular, numerous data point to the participation of TRIMs in the determination of stem cell fate, as well as in the neurogenesis. TRIMs apply various mechanisms to perform their functions. Their common feature is the ability to ubiquitinate proteins mediated by the Really Interesting New Gene (RING) domain. Different C-terminal domains of TRIMs are involved in DNA and RNA binding, protein/protein interactions, and chromatin-mediated transcriptional regulation. Mutations and alterations of TRIM expression cause significant disturbances in the stem cells' self-renewal and neurogenesis, which result in the various pathologies of the nervous system (neurodegeneration, neuroinflammation, and malignant transformation). This review discusses the diverse molecular mechanisms of participation of TRIMs in stem cell maintenance and self-renewal as well as in neural differentiation processes and neuropathology.

Therapeutic utility of glucocorticoids and antihistamines cotreatment. Rationale and perspectives

Antihistamines and glucocorticoids (GCs) are often used together in the clinic, in several inflammatory-related situations. Even though there is no clear rationale for this drug association, the clinical practice is based on the assumption that due to their concomitant antiinflammatory effects, there should be an intrinsic benefit in their coadministration. Our group has studied the molecular interaction between the histamine H1 receptor and the glucocorticoid receptor (GR) signaling pathways, showing an enhancing effect on GC-induced GR transcriptional activity induced by antihistamines. We hypothesize that the existence of this synergistic effect could contribute in reducing the GCs clinical doses, ineffective by itself but effective in combination with an antihistamine. This could result in a therapeutic advantage as the GC-desired effects may be reinforced by the addition of an antihistamine and, as a consequence of the dose reduction, GC-related adverse effects could be reduced or at least mitigated. Here we discuss the potential therapeutic applications of this cotreatment seeking to evaluate its usefulness, especially in inflammatory-related conditions.

Dexmedetomidine protects aged rats from postoperative cognitive dysfunction by alleviating hippocampal inflammation

The present study investigated the effect of dexmedetomidine on hippocampal inflammation and cognitive function in rats with postoperative cognitive dysfunction (POCD). A total of 80 healthy male Sprague Dawley rats were used, 72 of which developed POCD. The rats were randomly divided into four groups: The control, model, low-dose and high-dose dexmedetomidine anesthesia groups. A POCD model was established and dexmedetomidine was administered. Cognitive function tests were performed and expression levels of interleukin 1β (IL-1β), tumor necrosis factor-α (TNF-α) and NF-κB biomarkers were evaluated on the first, third and seventh day following modeling. The cognitive function of rats was measured using a Y-maze test. The expression levels of IL-1β and TNF-α in the hippocampus were determined by ELISA. The protein expression levels of NF-κB p65 in the hippocampus were determined by western blotting. It was revealed that at 1, 3 and 7 days after surgery, there were no alterations in the exercise ability of rats in the different groups, as reflected by the number of rats passing the alternative arms in the Y-maze. On the first and third day after surgery, the cognitive dysfunction reflected by the alteration scores of the low-dose and high-dose dexmedetomidine anesthesia groups were significantly higher than those of the model group, and the increase in the high-dose group was more pronounced. Additionally, on the first day after surgery, the expression levels of IL-1β, TNF-α and NF-κB in the hippocampi of rats in the low- and high-dose dexmedetomidine anesthesia groups were significantly lower than those in the model group, and the decrease was more pronounced in the high-dose group. At 7 days after surgery, the differences in expression levels of IL-1β, TNF-α and NF-κB in the hippocampus among groups were not identified to be statistically significantly different. Taken together, the results of the present study indicated that dexmedetomidine may inhibit hippocampal inflammation induced by surgical trauma, and that dexmedetomidine may effectively improve postoperative cognitive function in rats.

Evaluation of Endothelial Dysfunction in Bipolar Affective Disorders: Serum Endocan and Urotensin-II Levels

Objective

This study investigated changes in urotensin-II (U-II) and endocan levels which can be used as an early biological marker of endothelial injury in the episode and remission phases of bipolar affective disorder (BAD).

Methods

We compared endocan and U-II levels, which has been shown to be closely associated with neurotransmitter systems in addition to continuity of endothelial structure and inflammatory response, in patients with BAD in remission for at least one year (n=42) and in patients still in manic or depressive episodes (n=16) with healthy controls (n=30).

Results

Both endocan and U-II levels were significantly higher in the bipolar patients than in the controls. Endocan and U-II levels were also significantly correlated with one another (p=0.000, r=0.833). Both endocan (p=0.000) and U-II levels (p=0.000) were significantly higher in the bipolar attack group compared to the subjects in remission, and in the remission group compared to the controls.

Conclusion

In this study we determined significantly higher endocan and U-II levels in BAD compared to the controls, while serum endocan and U-II levels of patients undergoing attacks were also significantly higher than those of the controls and also those of patients in remission.

Toll-like receptors in the pathogenesis of neuroinflammation

Toll-like receptors (TLRs) are discovered as crucial pattern recognition receptors (PRRs) involved in the recognition of pathogen-associated molecular patterns (PAMPs). Later studies showed their involvement in the recognition of various damage/danger-associated molecular patterns (DAMPs) generated by host itself. Thus, TLRs are capable of recognizing wide-array of patterns/molecules derived from pathogens and host as well and initiating a proinflammatory immune response through the activation of NF-κB and other transcription factors causing synthesis of proinflammatory molecules. The process of neuroinflammation is seen under both sterile and infectious inflammatory diseases of the central nervous system (CNS) and may lead to the development of neurodegeneration. The present article is designed to highlight the importance of TLRs in the pathogenesis of neuroinflammation under diverse conditions. TLRs are expressed by various immune cells present in CNS along with neurons. However out of thirteen TLRs described in mammals, some are present and active in these cells, while some are absent and are described in detail in main text. The role of various immune cells present in the brain and their role in the pathogenesis of neuroinflammation depending on the type of TLR expressed is described. Thereafter the role of TLRs in bacterial meningitis, viral encephalitis, stroke, Alzheimer's disease (AD), Parkinson's disease (PD), and autoimmune disease including multiple sclerosis (MS) is described. The article is designed for both neuroscientists needing information regarding TLRs in neuroinflammation and TLR biologists or immunologists interested in neuroinflammation.

Influence of different rehabilitative aerobic exercise programs on (anti-) inflammatory immune signalling, cognitive and functional capacity in persons with MS - study protocol of a randomized controlled trial

BACKGROUND

Studies have shown positive effects of therapeutic exercise on motor- and cognitive function as well as on psychosocial outcomes in persons with multiple sclerosis (MS). A reduction of inflammatory stress through physical exercise has been suspected as one key mechanism, mediating the positive effects of exercise in the context of MS. The primary objective of this trial is to investigate the acute and chronic effects of different exercise modalities on (anti-)inflammatory immune signalling as well as on cognitive and functional capacity in persons with MS.

METHODS

A two armed single-blind randomized controlled design will investigate 72 persons with relapsing remitting or secondary progressive MS (EDSS 3.0-6.0), during 3 weeks of inpatient rehabilitation. Participants will be randomized into either a high-intensity interval training (HIIT) or a moderate continuous training group; the latter represents the local standard therapy (ST). Both groups will exercise 3x per week. The HIIT group will perform 5 × 1.5-min high-intensive exercise bouts at 95-100% of their maximum heart rate (HRmax) followed by active breaks of unloaded pedalling (60% HRmax) for 2 min. In contrast, the ST group will exercise for 24 min continuously at 65% of HRmax. The proportion of circulating regulatory T-cells will be measured as primary outcome. Secondary outcomes comprise numbers and proportions of further immune cells including Th17-cells, soluble factors ((anti-) inflammatory cytokines, tryptophan metabolites), endurance capacity, cognitive performance, processing skills for activities of daily living, fatigue, depression and healthcare-related quality of life. Outcomes will be assessed before (T0) and after (T3) the 3-week exercise intervention program. Blood samples of T0 will be taken immediately before the first exercise session. Additionally, blood samples for the soluble factors will be collected immediately after (T1) and three hours (T2) after the first exercise session of each group.

DISCUSSION

This study will be the first to investigate both acute and chronic effects of aerobic exercise on immune function and disease associated biomarkers in persons with MS. Combining biological analyses with cognitive and functional capacity assessments may contribute to a better understanding of responses to rehabilitative training, needed to improve exercise recommendations for persons with MS.

TRIAL REGISTRATION

This trial was prospectively registered at ClinicalTrials.gov ( NCT03652519 ; 29 August 2018).

Evaluation of the anti-oxidant and anti-inflammatory effects of the methanolic extract of Ferula szowitsiana root on PHA-induced inflammation in human lymphocytes

Inflammation is defined as a defensive response of the body against either the endogenous or exogenous triggers, while this process becomes chronic leading to various disorders such as asthma, cancers, and multiple sclerosis. Recently, pharmacological properties of different constituents of F. szowitsiana have been reported. In the present study, we aimed to evaluate the anti-oxidative and anti-inflammatory effects of the methanolic extract of F. szowitsiana root on human isolated lymphocytes. The effects of either F. szowitsiana (10, 40 and 160 μg/ml) or dexamethasone (0.1 mM) were evaluated on the levels of cell proliferation, reactive oxygen species (ROS), nitric oxide (NO) production, malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) activities, and total glutathione content (GSH) as well as the secretion of inflammatory cytokines [interleukin 6 (IL-6) and tumor necrosis factor (TNF)-α] in the presence or absence of phytohemagglutinin (PHA) stimulation (n = 8 for each group). PHA stimulation notably elevated ROS, NO, MDA, IL-6, and TNF-α levels as well as diminished GSH, CAT and SOD levels. In PHA-stimulated, the results also revealed that F. szowitsiana (10-160 µg/ml) significantly decreased MDA, ROS, NO, IL-6 and TNF-α levels as well as increased CAT, SOD and GSH levels. Collectively, F. szowitsiana is able to attenuate the overproduction of inflammatory and oxidative stress markers in the presence of PHA-stimulated T lymphocytes, while to propagate the anti-oxidative defense. Contextually, the plant has promising healing effects in the different inflammatory disorders associated with the interference of the acquired immune system such as multiple sclerosis and asthma.

Activation of microglia synergistically enhances neurodegeneration caused by MPP+ in human SH-SY5Y cells

While MPP⁺ may not directly activate microglia, the initial neuronal damage inflicted by the toxin may trigger microglia, possibly leading to synergistic pro-apoptotic interaction between neuro-inflammation and toxin-induced neurotoxicity, which may further aggravate neurodegeneration. However, what molecular targets are synergistically up or downregulated during this interaction is not well understood. Here, we addressed this by co-culturing fully differentiated human SH-SY5Y cells treated with parkinsonian toxin 1-Methyl-4-phenylpyridinium (MPP⁺), with endotoxin-activated microglial cell line EOC 20 to determine how this interaction affects pro-apoptotic (p38, JNK, and bax:bcl2 ratios) and pro-survival (NF-κB, MEK1) signaling at both mRNA and protein levels. Concurrent MPP⁺ and endotoxin-treatment aggravated a decrease in SH-SY5Y cell viability and caused strong synergistic increases in the bax:bcl2 ratio, but also NF-κB and JNK signaling. These effects were attenuated by microglia inhibitor minocycline. Altogether, these data provide further molecular insights into the important role or even conditional requirement of microglia activation in the progressive neurodegenerative nature of PD.

The Prophylactic and Therapeutic Effects of Fermented Cordyceps sinensis Powder, Cs-C-Q80, on Subcortical Ischemic Vascular Dementia in Mice

Corbrin Capsule, a preparation of Cordyceps sinensis analogue, is a pleiotropic traditional Chinese patent medicine with the main component of fermentative cordyceps fungus powder (Cs-C-Q80). The neuroprotective effects of Cs-C-Q80, as a substitution of Cordyceps sinensis, have not been fully identified. The objectives of this study were to explore the prophylactic and therapeutic effects of Cs-C-Q80 in vascular dementia mice model. The efficacy of Cs-C-Q80 was investigated in a molecular level as well. The subcortical ischemic vascular dementia was modelled by permanent right unilateral common carotid arteries occlusion (rUCCAO) in adult male mice. The animals were randomly divided and treated by gavage with vehicle (1% CMC-Na solution) (rUCCAO model) or Cs-C-Q80 powder at 0.2 g/kg or 1.0 g/kg, respectively. Preventive treatment was administrated by gavage daily for 7 days before rUCCAO, while therapeutic treatment was administrated continuously from 28 days after rUCCAO. Object recognition test and Morris water maze test were performed to evaluate the learning and working memory. The luxol fast blue stain (Kluver-Barrera method) and immunohistochemistry for myelin basic protein (MBP) were employed to determine the severity of white matter damage. Both preventive and therapeutic treatment with Cs-C-Q80 protected against the rUCCAO-induced memory impair in mice as determined by object recognition and Morris water maze tests. The histopathological analyses revealed significant white matter rarefaction and reduction of MBP expression in corpus callosum after rUCCAO, which could be counteracted by either preventive or therapeutic treatment with Cs-C-Q80. Moreover, the Cs-C-Q80 treatments inhibited rUCCAO-induced astrocytes activation and the tumor necrosis factor α (TNF-α) and interleukin-1β expression, indicating the anti-inflammatory roles of Cs-C-Q80 against subcortical ischemia. Cs-C-Q80 is a potential preparation for the prophylaxis and treatment of subcortical ischemic vascular dementia. The underlying pharmacological efficacy might be associated with suppression of myelin degeneration, glia activation, and inflammatory cytokines release.

Computational Studies Applied to Flavonoids against Alzheimer's and Parkinson's Diseases

Neurodegenerative diseases, such as Parkinson's and Alzheimer's, are understood as occurring through genetic, cellular, and multifactor pathophysiological mechanisms. Several natural products such as flavonoids have been reported in the literature for having the capacity to cross the blood-brain barrier and slow the progression of such diseases. The present article reports on in silico enzymatic target studies and natural products as inhibitors for the treatment of Parkinson's and Alzheimer's diseases. In this study we evaluated 39 flavonoids using prediction of molecular properties and in silico docking studies, while comparing against 7 standard reference compounds: 4 for Parkinson's and 3 for Alzheimer's. Osiris analysis revealed that most of the flavonoids presented no toxicity and good absorption parameters. The Parkinson's docking results using selected flavonoids as compared to the standards with four proteins revealed similar binding energies, indicating that the compounds 8-prenylnaringenin, europinidin, epicatechin gallate, homoeriodictyol, capensinidin, and rosinidin are potential leads with the necessary pharmacological and structural properties to be drug candidates. The Alzheimer's docking results suggested that seven of the 39 flavonoids studied, being those with the best molecular docking results, presenting no toxicity risks, and having good absorption rates (8-prenylnaringenin, europinidin, epicatechin gallate, homoeriodictyol, aspalathin, butin, and norartocarpetin) for the targets analyzed, are the flavonoids which possess the most adequate pharmacological profiles.

Polydatin Prevents Lipopolysaccharide (LPS)-Induced Parkinson's Disease via Regulation of the AKT/GSK3β-Nrf2/NF-κB Signaling Axis

Parkinson's disease (PD) is a common neurodegenerative disease characterized by selective loss of dopaminergic neurons in the substantia nigra (SN). Neuroinflammation induced by over-activation of microglia leads to the death of dopaminergic neurons in the pathogenesis of PD. Therefore, downregulation of microglial activation may aid in the treatment of PD. Polydatin (PLD) has been reported to pass through the blood-brain barrier and protect against motor degeneration in the SN. However, the molecular mechanisms underlying the effects of PLD in the treatment of PD remain unclear. The present study aimed to determine whether PLD protects against dopaminergic neurodegeneration by inhibiting the activation of microglia in a rat model of lipopolysaccharide (LPS)-induced PD. Our findings indicated that PLD treatment protected dopaminergic neurons and ameliorated motor dysfunction by inhibiting microglial activation and the release of pro-inflammatory mediators. Furthermore, PLD treatment significantly increased levels of p-AKT, p-GSK-3βSer9, and Nrf2, and suppressed the activation of NF-κB in the SN of rats with LPS-induced PD. To further explore the neuroprotective mechanism of PLD, we investigated the effect of PLD on activated microglial BV-2 cells. Our findings indicated that PLD inhibited the production of pro-inflammatory mediators and the activation of NF-κB pathways in LPS-induced BV-2 cells. Moreover, our results indicated that PLD enhanced levels of p-AKT, p-GSK-3βSer9, and Nrf2 in BV-2 cells. After BV-2 cells were pretreated with MK2206 (an inhibitor of AKT), NP-12 (an inhibitor of GSK-3β), or Brusatol (BT; an inhibitor of Nrf2), treatment with PLD suppressed the activation of NF-κB signaling pathways and the release of pro-inflammatory mediators in activated BV-2 cells via activation of the AKT/GSK3β-Nrf2 signaling axis. Taken together, our results are the first to demonstrate that PLD prevents dopaminergic neurodegeneration due to microglial activation via regulation of the AKT/GSK3β-Nrf2/NF-κB signaling axis.

Microglia in the Neurovascular Unit: Blood-Brain Barrier-microglia Interactions After Central Nervous System Disorders

Over the past few decades, microglial cells have been regarded as the main executor of inflammation after acute and chronic central nervous system (CNS) disorders, responding rapidly to exogenous stimuli during acute trauma or infections, or signals released by cells undergoing cell death during conditions such as stroke, Alzheimer's disease (AD) and Parkinson's disease (PD). Barriers of the nervous system, and in particular the blood-brain barrier (BBB), play a key role in the normal physiological and cognitive functions of the brain. Being at the interface between the central and peripheral compartment, the BBB is regarded as a sensor of homeostasis, and any disruption within the brain or the systemic compartment triggers BBB dysfunction and neuroinflammation, both contributing to the pathogenesis of cerebrovascular disease. This involves a dynamic response mediated by all components of the neurovascular unit (NVU), and ongoing research suggests that BBB-microglia interaction is critical to dictate the microglial response to NVU injury. The present review aims to give an up-to-date account of the emerging critical role of BBB-microglia interactions during neuroinflammation, and how these could be targeted for the therapeutic treatment of major central inflammatory disease.