Brain Protein Research Articles

Protein glycosylation and glycoinformatics for novel biomarker discovery in neurodegenerative diseases.

Glycosylation is a common post-translational modification of brain proteins including cell surface adhesion molecules, synaptic proteins, receptors and channels, as well as intracellular proteins, with implications in brain development and functions. Using advanced state-of-the-art glycomics and glycoproteomics technologies in conjunction with glycoinformatics resources, characteristic glycosylation profiles in brain tissues are increasingly reported in the literature and growing evidence shows deregulation of glycosylation in central nervous system disorders, including aging associated neurodegenerative diseases. Glycan signatures characteristic of brain tissue are also frequently described in cerebrospinal fluid due to its enrichment in brain-derived molecules. A detailed structural analysis of brain and cerebrospinal fluid glycans collected in publications in healthy and neurodegenerative conditions was undertaken and data was compiled to create a browsable dedicated set in the GlyConnect database of glycoproteins (https://glyconnect.expasy.org/brain). The shared molecular composition of cerebrospinal fluid with brain enhances the likelihood of novel glycobiomarker discovery for neurodegeneration, which may aid in unveiling disease mechanisms, therefore, providing with novel therapeutic targets as well as diagnostic and progression monitoring tools.

125I]INFT: Synthesis and Evaluation of a New Imaging Agent for Tau Protein in Post-Mortem Human Alzheimer's Disease Brain.

Aggregation of Tau protein into paired helical filaments causing neurofibrillary tangles (NFT) is a neuropathological feature in Alzheimer's disease (AD). This study aimed to develop and evaluate the effectiveness of a novel radioiodinated tracer, 4-[125I]iodo-3-(1H-pyrrolo[2,3-c]pyridine-1-yl)pyridine ([125I]INFT), for binding to Tau protein in postmortem human AD brain. Radiosynthesis of [125I]INFT was carried out using electrophilic destannylation by iodine-125 and purified chromatographically. Computational modeling of INFT binding on Tau fibril was compared with IPPI. In vitro, autoradiography studies were conducted with [125I]INFT for Tau in AD and cognitively normal (CN) brains. [125I]INFT was produced in >95% purity. Molecular modeling of INFT revealed comparable binding energies to IPPI at site-1 of the Tau fibril with an affinity of IC50 = 7.3 × 10-8 M. Binding of [125I]INFT correlated with the presence of Tau in the AD brain, confirmed by anti-Tau immunohistochemistry. The ratio of average grey matter (GM) [125I]INFT in AD versus CN was found to be 5.9, and AD GM/white matter (WM) = 2.5. Specifically bound [125I]INFT to Tau in AD brains was displaced by IPPI (>90%). Monoamine oxidase inhibitor deprenyl had no effect and clorgyline had little effect on [125I]INFT binding. [125I]INFT is a less lipophilic imaging agent for Tau in AD.

Homocysteine Metabolites Inhibit Autophagy, Elevate Amyloid Beta, and Induce Neuropathy by Impairing Phf8/H4K20me1-dependent Epigenetic Regulation of mTOR in Cystathionine β-Synthase-Deficient Mice.

The loss of cystathionine β-synthase (CBS), an important homocysteine (Hcy)-metabolizing enzyme or the loss of PHF8, an important histone demethylase participating in epigenetic regulation, causes severe intellectual disability in humans. Similar neuropathies were also observed in Cbs-/- and Phf8-/- mice. How CBS or PHF8 depletion can cause neuropathy was unknown. To answer this question, we examined a possible interaction between PHF8 and CBS using Cbs-/- mouse and neuroblastoma cell models. We quantified gene expression by RT-qPCR and Western blotting, mTOR-bound H4K20me1 by chromatin immunoprecipitation (CHIP) assay, and amyloid β (Aβ) by confocal fluorescence microscopy using anti-Aβ antibody. We found significantly reduced expression of Phf8, increased H4K20me1, increased mTOR expression and phosphorylation, and increased App, both on protein and mRNA levels in brains of Cbs-/- mice vs. Cbs+/- sibling controls. Autophagy-related Becn1, Atg5, and Atg7 were downregulated while p62, Nfl, and Gfap were upregulated on protein and mRNA levels, suggesting reduced autophagy and increased neurodegeneration in Cbs-/- brains. In mouse neuroblastoma N2a or N2a-APPswe cells, treatments with Hcy-thiolactone, N-Hcy-protein or Hcy, or Cbs gene silencing by RNA interference significantly reduced Phf8 expression and increased total H4K20me1 as well as mTOR promoter-bound H4K20me1. This led to transcriptional mTOR upregulation, autophagy downregulation, and significantly increased APP and Aβ levels. The Phf8 gene silencing increased Aβ, but not APP, levels. Taken together, our findings identify Phf8 as a regulator of Aβ synthesis and suggest that neuropathy of Cbs deficiency is mediated by Hcy metabolites, which transcriptionally dysregulate the Phf8- > H4K20me1- > mTOR- > autophagy pathway thereby increasing Aβ accumulation. This article is protected by copyright. All rights reserved.

Compilation of reported protein changes in the brain in Alzheimer’s disease

Proteomic studies of human Alzheimer’s disease brain tissue have potential to identify protein changes that drive disease, and to identify new drug targets. Here, we analyse 38 published Alzheimer’s disease proteomic studies, generating a map of protein changes in human brain tissue across thirteen brain regions, three disease stages (preclinical Alzheimer’s disease, mild cognitive impairment, advanced Alzheimer’s disease), and proteins enriched in amyloid plaques, neurofibrillary tangles, and cerebral amyloid angiopathy. Our dataset is compiled into a searchable database (NeuroPro). We found 848 proteins were consistently altered in 5 or more studies. Comparison of protein changes in early-stage and advanced Alzheimer’s disease revealed proteins associated with synapse, vesicle, and lysosomal pathways show change early in disease, but widespread changes in mitochondrial associated protein expression change are only seen in advanced Alzheimer’s disease. Protein changes were similar for brain regions considered vulnerable and regions considered resistant. This resource provides insight into Alzheimer’s disease brain protein changes and highlights proteins of interest for further study.

Detection, visualization and quantification of protein complexes in human Alzheimer’s disease brains using proximity ligation assay

Examination of healthy and diseased human brain is essential to translational neuroscience. Protein–protein interactions play a pivotal role in physiological and pathological processes, but their detection is difficult, especially in aged and fixed human brain tissue. We used the in-situ proximity ligation assay (PLA) to broaden the range of molecular interactions assessable in-situ in the human neuropathology. We adapted fluorescent in-situ PLA to detect ubiquitin-modified proteins in human brains with Alzheimer’s disease (AD), including approaches for the management of autofluorescence and quantification using a high-content image analysis system. We confirmed that phosphorylated microtubule-associated protein tau (Serine202, Threonine205) aggregates were modified by ubiquitin and that phospho-tau-ubiquitin complexes were increased in hippocampal and frontal cortex regions in AD compared to non-AD brains. Overall, we refined PLA for use in human neuropathology, which has revealed a profound change in the distribution of ubiquitin in AD brain and its association with characteristic tau pathologies.

Cdk5-Mediated Brain Unfolded Protein Response Upregulation Associated with Cognitive Impairments in Type 2 Diabetes and Ameliorative Action of NAC.

The role of cyclin-dependent kinase 5 (Cdk5) in the normal functioning of the central nervous system and synaptic plasticity is well established. However, dysregulated kinase activity can have a significant impact on neurodegeneration and cognitive impairment. Cdk5 hyperactivation is linked to diabetes-associated neurodegeneration, but the underlying mechanism is not fully understood. Our study reveals that oxidative stress can lead to Cdk5 hyperactivity, which in turn is linked to neurodegeneration and cognitive impairment. Specifically, our experiments with N2A cells overexpressing Cdk5 and its activators p35 and p25 show ER stress, resulting in activation of the unfolded protein response (UPR) pathway. We identified Cdk5 as the epicenter of this regulatory process, leading to the activation of the CDK5-IRE1-XBP1 arm of UPR. Moreover, our study demonstrated that Cdk5 hyperactivation can lead to ER stress and activation of the UPR pathway, which may contribute to cognitive impairments associated with diabetes. Our findings also suggest that antioxidants such as NAC and GSH can decrease deregulated Cdk5 kinase activity and rescue cells from UPR-mediated ER stress. The accumulation of phosphorylated Tau protein in AD brain protein has been widely described earlier. Notably, we observed that oral treatment with NAC decreased Cdk5 kinase activity in the hippocampus, attenuated high levels of phospho-tau (ser396), and ameliorated memory and learning impairments in a type 2 diabetic (T2D) mouse model. Additionally, the high-fat-induced T2D model exhibits elevated phospho-tau levels, which are rescued by the NAC treatment. Taken together, these results suggest that targeting Cdk5 may be a promising therapeutic strategy for treating diabetes-associated cognitive impairments.

Regulation of tight junction proteins and cell death by peroxisome proliferator-activated receptor γ agonist in brainstem of hypertensive rats.

The decrease in tight junction proteins and their adapter proteins in the hypertensive brain is remarkable. Here, we aimed to investigate tight junction proteins and peroxisome proliferator-activated receptor (PPARγ) activation as well as inflammation factors and cell death proteins in the brainstem of hypertension models, namely spontaneously hypertensive rats (SHR) and borderline hypertensive rats (BHR). At first, SHR and BHR groups were treated with PPARγ agonist, pioglitazone. Then, occludin, claudin-1, claudin-2, claudin-12, ZO-1, and NF-κB p65 gene expression levels; pIKKβ, NF-κB p65, TNF, IL-1β, caspase-3, caspase-9 levels, and PARP-1 cleavage were evaluated. Significantly lower pIKKβ, NF-κB p65, TNF, and IL-1β levels were measured in pioglitazone-treated SHR. Results from this study confirm higher occludin (1.35-fold), claudin-2 (7.45-fold), claudin-12 (1.12-fold), and NF-κB p65 subunit (4.76-fold) expressions in the BHR group when compared to the SHR group. Pioglitazone was found effective in terms of regulating gene expression in SHR. Pioglitazone significantly increased occludin (8.17-fold), claudin-2 (2.41-fold), and claudin-12 (1.85-fold) mRNA levels, which were accompanied by decreased cleaved caspase-3, caspase-9 levels, PARP-1 activation, and proinflammatory factor levels in SHR (p ˂ 0.05). Our work has led us to conclude that alterations in tight junction proteins, particularly occludin, and cell death parameters in the brainstem following PPARγ activation may contribute to neuroprotection in essential hypertension.

Integrated proteomics and metabolomics reveals metabolism disorders in the α-syn mice and potential therapeutic effect of Acanthopanax senticosus extracts

Ethnopharmacological relevanceAcanthopanax senticosus (Rupr.et.Maxim.)Harms(AS) is an extract of Eleutherococcus senticocus Maxim(Rupr.et.Maxim.). In modern medical interpretation, Acanthopanax senticosus can be used to treat Parkinson's disease, and a large number of modern pharmacological and clinical studies also support this application. Our study demonstrated that AS extracts can increase the activity of various antioxidant enzymes and improve the symptoms of Parkinson's disease in mice. Aim of the studyThe current study looked at the protective effect of Acanthopanax senticosus extracts(ASE) in preventing PD. Methods and materialsFirst, the α-syn-overexpressing mice were chosen as suitable models for Parkinson's disease in vivo. HE staining was used to observe the pathological changes in the substantia nigra. Meanwhile, TH expression in substantia nigra was analyzed by immunohistochemistry. Behavioral and biochemical tests evaluated neuroprotective effects of ASE on PD mice. Subsequently, combined with proteomics and metabolomics analysis, the changes in brain proteins and metabolites in mice treated with ASE for PD were studied. Finally, Western blot was used to detect metabolome-related and proteomic proteins in the brain tissue of α-syn mice. ResultsForty-nine common differentially expressed proteins were screened by proteomics analysis, among which 28 were significantly up-regulated,and 21 were significantly down-regulated. Metabolomics analysis showed that twenty-five potentially important metabolites were involved in the therapeutic effect of ASE on PD. Most of the different proteins and metabolites were considered to be enriched in a variety of species in metabolic pathways, including glutathione metabolism and alanine aspartate and glutamate metabolism and other pathways, which means that ASE may have molecular mechanisms to ameliorate PD dysfunction. In addition, we found that decreases in glutathione and glutathione disulfide levels may play a critical role in these systemic changes and warrant further investigation. In the glutathione metabolic pathway, ASE also acts on GPX4, GCLC and GCLM. ConclusionsASE can effectively relieve behavioral symptoms of α-syn mice and relieve oxidative stress in brain tissue. These findings suggest that ASE offers a potential solution to target these pathways for the treatment of PD.

Ischemic Stroke Shifts the Protein and Metabolite Profiles of Colon in Mice

Over half of all stroke patients present gastrointestinal complications. It has been speculated that there is an intriguing brain-gut connection. However, molecular mechanisms of the connection remain poorly illuminated. Thus, this study is aimed to investigate molecular alternations regarding proteins and metabolites in the colon upon ischemic stroke using multi-omics analyses. Here, stroke mouse model was induced by means of transient middle cerebral artery occlusion. After the confirmation of successful model evaluated as evidenced by neurological deficit and cerebral blood flow decrease, the proteins and metabolites of colon and brain were respectively measured using multiple omics. Functional analysis of differentially expressed proteins (DEPs) and differential metabolites was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation. There were 434 common DEPs in the colon and brain after stroke. The DEPs in the two tissues displayed common enrichment in several pathways upon GO/KEGG analyses. The common KEGG pathways of DEPs were mainly linked to the inflammation and immune network. Although there was no common differential metabolite and its corresponding pathway in the two tissues, several metabolism pathways in the colon were also changed after stroke. In conclusion, we have demonstrated that the proteins and metabolites in the colon are significantly changed after ischemic stroke, which provides molecular-level evidence regarding the brain-gut connection. In this light, several common enriched pathways of DEPs may become potential therapeutic targets for stroke upon the brain-gut axis. Notably, we have discovered a promising colon-derived metabolite enterolactone possibly beneficial for tackling stroke.

High frequency of cerebrospinal fluid autoantibodies in patients with seizures or epilepsies of unknown etiology.

The increasing identification of specific autoantibodies against brain structures allows further refinement of the group of autoimmune-associated epilepsies and affects diagnostic and therapeutic algorithms. The early etiological allocation of a first seizure is particularly challenging, and the contribution of cerebrospinal fluid (CSF) analysis is not fully understood. In this retrospective study with a mean of 7.8 years follow-up involving 39 well-characterized patients with the initial diagnosis of new-onset seizure or epilepsy of unknown etiology and 24 controls, we determined the frequency of autoantibodies to brain proteins in CSF/serum pairs using cell-based assays and unbiased immunofluorescence staining of unfixed murine brain sections. Autoantibodies were detected in the CSF of 30.8% of patients. Underlying antigens involved glial fibrillary acidic protein (GFAP) and N-methyl-D-aspartate (NMDA) receptors, but also a range of yet undetermined epitopes on neurons, glial and vascular cells. While antibody-positive patients had higher frequencies of cancer, they did not differ from antibody-negative patients with respect to seizure type, electroencephalography (EEG) and cranial magnetic resonance imaging (cMRI) findings, neuropsychiatric comorbidities or pre-existing autoimmune diseases. In 5.1% of patients with seizures or epilepsy of initially presumed unknown etiology, mostly CSF findings resulted in etiological reallocation as autoimmune-associated epilepy. These findings strengthen the potential role for routine CSF analysis. Further studies are needed to understand the autoantibody contribution to etiologically unclear epilepsies, including determining the antigenic targets of underlying autoantibodies.

Hypophyseal acetylcholinesterase, and growth hormones of broiler chicken fed Ficus carica and vitamin C supplemented diets

The research was conducted to investigate hypophyseal acetylcholinesterase and growth hormones of broiler chickens fed Ficus carica and Vitamin C supplemented diets. 160-day-old chicks were randomly assigned to 4 treatments supplemented with Ficus carica and vitamin C in 4 replicates and 10 birds per replicate. At the end of the 8th week, the brains and hypophyses of 3 randomly selected birds per treatment were removed and tested for Acetylcholinesterase activities and total protein determination while blood samples were collected for hormonal assay. Results showed that total protein of the whole brain (0.50 mg/dl) and cerebellum (0.12 mg/dl) were significantly (p<0.05) lower in birds fed control diet while that of the olfactory lobe was significantly higher than that of the control (0.25 mg/dl). However, the acetylcholinesterase activities (µmol/g tissue) of the optic lobe (0.36), Cerebellum (0.22), and medulla (0.25) of birds fed the control diet were significantly (p<0.05) higher than those fed supplemented diets. Also, all hormonal assays tested were significantly influenced by the treatments with the exception of thyroxine. Birds fed diet 4 had the highest record for most growth hormonal assay. From the results obtained, Diet IV could be recommended in broiler chickens’ diets for superior growth promotion.

The females' response to male attractiveness: Mate choice, larvae production and differential brain protein expression

AbstractSexual Selection has been studied predominantly from a functional perspective with relatively limited investigation of the mechanistic basis of female choice. In this study, we evaluated female choice and larvae production in response to attractive or less attractive males and concurrently examined the protein profile in the brains of females, using the mealworm beetle Tenebrio molitor as a model system. Females were found to prefer males with high levels of pheromones, which requires the secretion of juvenile hormone (JH). Male attractiveness was enhanced using the JH analog methoprene, resulting in less female rejection and higher mating frequency and offspring production. Importantly, reproductive success was not due to differences in testis size or sperm production, or viability. Out of the 1833 proteins detected in the brain, only 32 were differentially expressed in females mating with attractive versus less attractive males. These proteins involved memory, metabolism, olfactory detection, reproduction, and movement. Although some brain proteins have been linked to mate choice in vertebrates, most of the differentially expressed molecules found in this study have not been previously reported concerning mate choice.

Bmal1 downregulation leads to diabetic cardiomyopathy by promoting Bcl2/IP3R-mediated mitochondrial Ca2+ overload

Brain and muscle arnt-like protein 1 (Bmal1) is a crucial transcription factor, regulating circadian rhythm and involved in multiple heart diseases. However, it is unknown whether Bmal1 promotes diabetic cardiomyopathy (DCM) pathogenesis. The objective of this investigation was to ascertain the vital role of Bmal1 in the progression of DCM. Mice with T2D and H9c2 cardiomyoblasts exposed to high glucose and palmitic acid (HGHP) were used. Cardiomyocyte-specific knockout mouse of Bmal1 (CKB) was also generated, and cardiac Bmal1 was overexpressed in type 2 diabetes (T2D) mice using an adeno-associated virus. Bmal1 gene recombinant adenovirus was used to either knockdown or overexpress in H9c2 cardiomyoblasts. Bmal1 expression was significantly altered in diabetic mice hearts. Bmal1 downregulation in CKB and T2D mice heart accelerated cardiac hypertrophy and diastolic dysfunction, while Bmal1 overexpression ameliorated these pathological changes in DCM mice. Furthermore, DCM mice had significant mitochondrial ultrastructural defects, reactive oxygen species accumulation, and apoptosis, which could be alleviated by overexpressing Bmal1. In H9c2 cardiomyoblasts, genetic downregulation of Bmal1 or HGHP markedly decreased the binding of Bcl2 to IP3R, thus increasing Ca2+ release to mitochondria through mitochondria-associated endoplasmic reticulum membranes. Importantly, chromatin immunoprecipitation revealed Bmal1 could bind directly to the Bcl2 gene promoter region. Bmal1 overexpression augmented the Bmal1/Bcl2 binding, enhancing the inhibition of Bcl2 on IP3R activity, thus alleviating mitochondrial Ca2+ overload and subsequent cell apoptosis. These results show that Bmal1 is involved in the DCM development through Bcl2/IP3R-mediated mitochondria Ca2+ overload. Therapy targeting the circadian clock (Bmal1) can treat DCM.

Proteome Profiling of Rat Brain Cortical Changes during Early Postnatal Brain Development.

Label-free quantitation (LFQ) was applied to proteome profiling of rat brain cortical development during the early postnatal period. Male and female rat brain extracts were prepared using a convenient, detergent-free sample preparation technique at postnatal days (PND) 2, 8, 15, and 22. The PND protein ratios were calculated using Proteome Discoverer, and the PND protein change profiles were constructed separately for male and female animals for key presynaptic, postsynaptic, and adhesion brain proteins. The profiles were compared to the analogous profiles assembled from the published mouse and rat cortex proteomic data, including the fractionated-synaptosome data. The PND protein-change trendlines, Pearson correlation coefficient (PCC), and linear regression analysis of the statistically significant PND protein changes were used in the comparative analysis of the datasets. The analysis identified similarities and differences between the datasets. Importantly, there were significant similarities in the comparison of the rat cortex PND (current work) vs mouse (previously published) PND profiles, although in general, a lower abundance of synaptic proteins in mice than in rats was found. The male and female rat cortex PND profiles were expectedly almost identical (98-99% correlation by PCC), which also substantiated this LFQ nanoflow liquid chromatography-high-resolution mass spectrometry approach.

An improved sulfur-nitroso-proteome strategy for global profiling of sulfur-nitrosylated proteins and sulfur-nitrosylation sites in mice

Comprehensive sulfur-nitrosylation (SNO) proteome coverage in complex biological systems remains challenging as a result of the low level of endogenous S-nitrosylation and its chemical instability. Herein, we optimized the synthesis route of SNOTRAP (SNO trapping by triaryl phosphine) probe and the proteomics pipeline (including preventing over-alkylation, sample washing, trypsin digestion). Preventing overalkylation was found to be the key factor resulting in a higher number of identified SNO proteins by evaluating various experimental conditions. With the improved SNOTRAP-based proteomic pipeline, we achieved an improvement of ∼10-fold on identification efficiency, and identified 1181 SNO proteins (1714 SNO sites) in mouse brain, representing the largest repository of endogenous S-nitrosylation. Moreover, we identified the consensus motif of SNO sites, suggesting the correlation with local hydrophobicity, acid-base catalysis, and the surrounding secondary structures for modification of specific cysteines by NO. Collectively, we provide a universal pipeline for the high-coverage identification of low-abundance SNO proteins with high enrichment efficiency, high specificity (98%), good reproducibility, and easy implementation, contributing to the elucidation of the mechanism(s) of nitrosative stress in multiple diseases.

Melatonin Alters Innate Immune Function in Infants with Neonatal Encephalopathy

Introduction: Melatonin has been suggested an adjunctive therapy in neonatal encephalopathy (NE). Melatonin reduces oxidative stress and neutrophil activation; however, the immunological effects in NE have not been studied. Methods: Infants with NE and neonatal controls were prospectively recruited. Whole blood was sampled in the first week of life. Following endotoxin and or melatonin treatment, diurnal variation was measured by RT PCR for circadian rhythm genes (brain and Muscle Arnt-Like protein [BMAL1], circadian locomotor output cycles kaput [CLOCK], Nuclear Receptor Subfamily 1 Group D Member 2 [REV Erβ], and cryptochrome circadian clock [CRY]). Neutrophil and monocyte cell surface markers of activation CD11b, reactive oxygen intermediates (ROIs), and Toll-like receptor (TLR)-4 were also examined by flow cytometry in matching samples. Results: Serum and RNA samples from forty infants were included (controls n = 20; NE n = 20) over the first week of life. Melatonin reduced neutrophil CD11b and TLR-4 expression in response to LPS in infants with NE compared to controls. There were no differences in ROIs. BMAL1 and CLOCK baseline gene expression levels were similar. BMAL1 was significantly decreased with LPS stimulation in NE. There was no significant diurnal variation in melatonin, neutrophil, and monocyte function or circadian genes. Conclusions: Melatonin alters immune function ex vivo in infants with NE. Infants with NE have altered immune circadian responses following LPS stimulation, which have potential for modulation.

Sleep-promoting activity of amylase-treated Ashwagandha (Withania somnifera L. Dunal) root extract via GABA receptors.

Ashwagandha (Withania somnifera L. Dunal), an Indian medicinal plant that has been used for centuries to treat insomnia, exhibits a variety of biological activities, such as improving cognitive function, immunity and anxiety. In this study, the effect of enzyme-treated Ashwagandha root extract (EA) and on sleep was evaluated using rodent models. Starch contained in the Ashwagandha root extract was removed by amylase treatment to prepare EA. To evaluate the sleep-promoting activity of EA, a pentobarbital-induced sleep test and electroencephalogram analysis were performed. In addition, the sleep-promoting mechanism of EA was elucidated by analyzing the expression of sleep-related receptors. In the pentobarbital-induced sleep test, EA dose-dependently increased sleep duration. Additionally, electroencephalogram analysis revealed that EA significantly increased δ-wave and non-rapid eye movement sleep times, which are involved in deep sleep, thereby improving sleep quality and quantity. EA also effectively relieved caffeine-induced insomnia symptoms. Furthermore, the γ-aminobutyric acid (GABA) content in the brain and mRNA and protein expression of GABAA, GABAB1, and serotonin receptors were significantly increased by EA compared to the normal group. In particular, EA showed sleep-promoting activity by binding to various GABAA receptor sites. Collectively, EA exhibited sleep-promoting activity through the GABAergic system and may be used as a functional material to improve sleep deprivation.

Hydroxyquinoline sulfanilamide ameliorates STZ-induced hyperglycemia-mediated amyleoid beta burden and memory impairment in adult mice

Abstract The aim of the current study was to evaluate therapeutic potentials of Hydroxyquinoline Sulfanilamide (HSM) for Alzheimer’s disease in a mice model of Streptozotocin (STZ)-induced diabetes. The antioxidant analysis of mice brain homogenates was carried out by catalase (CAT) assay, reduced glutathione (GSH) assay, and lipid peroxidation (LPO) assay. Biochemical analysis of blood plasma was conducted by peroxidase (POD) assay and superoxide dismutase (SOD) assay. The expression of mice brain proteins was evaluated using Western Blotting analysis. The administration of HSM increased the activity of antioxidant enzymes including CAT, SOD, GSH, and POD and lowered LPO actions. These findings indicate that STZ may lead to diabetes in mice, followed by hypercholesterolemia, expressed as triglycerides in mice blood. However, HSM significantly decreased STZ-induced hyperglycemia and hypercholesterolemia in adult albino mice. The data confirmed that HSM lowered STZ-induced oxidative stress, inhibited phosphorylated JNK, NF-kB, and upregulated Nrf-2 to improve and restore the synapse and memory defects in adult albino mice. Conclusively, the current findings suggested that HSM is a safe, novel, and potential drug candidate against metabolic dysfunction and induced cognitive impairment.

Identification of Mild cognitive impairment based on quadruple GCN model constructed with multiple features from higher-order brain connectivity

Mild cognitive impairment (MCI) is the early stage of Alzheimer's disease, which is associated with abnormal brain proteins, the recognition of MCI being a challenging task. Recent studies have shown that the performance of MCI identification can be improved by combining protein features captured in Positron Emission Computed Tomography(PET). Nevertheless, there are still great challenges in extracting effective features from the vast amount of information. Most brain networks only considered the unilateral features of nodes or edges, ignored the interactions between them. In response to this problem, our study proposed to combine the quadruple Siamese network and GCN with self-attention pooling(QS-SAGCN) for MCI identification. In detail, we constructed the multiple protein features network(MPN) and higher-order MPN(MPHN) by PET images to promote the MCI identification. Furthermore, a pooling operation with self-attention mechanism was incorporated into GCN(SAGCN), which considered the node characteristics and topology in the graph network to facilitate the acquisition of robust biomarkers, simultaneously. Additionally we combined quadruple Siamese network with SAGCN as classification framework to improve the identification accuracy. Our proposed MCI identification method was evaluated on 230 subjects (including 117 MCI subjects, 113 normal control subjects) with both 18F-AV-1451 PET and 18F-AV-45 PET data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database. Experimental results showed that 1) QS-SAGCN enhanced the ability of feature identification, laying the foundation for obtaining more effective biomarkers for MCI patients; 2) The MCI identification accuracy (93.5%) was obtained by combining QS-SAGCN and higher-order network, indicating that the framework had advantages in mental disorders recognition. Finally, through comparison, the accuracy of our proposed MCI recognition method was superior to some of the existing state-of-the-art methods. Overall, the MCI identification method in this study was effective and promising to assist in the diagnosis of MCI in future clinical practice.

Herpes Simplex Virus‐1 Proteins as Drivers for Alzheimer’s Disease Pathologies

AbstractBackgroundDNA and RNA of Herpes Simplex Virus 1 (HSV‐1) were found in the brains and serological samples of Alzheimer’s disease (AD) patients. Such molecular presence of HSV‐1 in AD patients is especially intriguing as HSV‐1 virions are rarely detected in AD brains.MethodTo follow the molecular footsteps detected, we imaged viral proteins in postmortem human AD brains at superior resolution using expansion microscopy, a tissue manipulation method that physically expands the samples by a factor of 4.5x, allowing a 40 nm imaging resolution, and immunolabeled herpetic proteins, AD pathologies and cell markers.ResultWe found an abundance of herpetic proteins, previously undetectable with standard methods, across large brain areas. Importantly, we found that HSV‐1 proteins strongly co‐localized with AD pathologies. Consequently, we hypothesized that expression of HSV‐1 proteins during latency may be linked to AD pathology. We are now in the process of characterizing the HSV‐1 proteome in AD brains by imaging key proteins in expanded AD brain slices and examining their colocalization with AD pathologies across brain areas and disease stages. As a complementary system to the fixed human brain slices, we are exposing live human brain organoids, to HSV‐1, and imaging the relationships between viral proteins and the formation of AD pathologies via expansion microscopy.ConclusionPathogens may be triggers of immune responses driving AD; this study would shed light on one common pathogen, HSV‐1, while serving as a framework to unveiling molecular causation between infectious agents and AD hallmarks.