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Membranous Nephropathy (MN) is characterized by the presence of subepithelial deposits. MN has been traditionally classified as primary if it is not associated with other pathologies, or secondary if it is associated with autoimmune diseases, infections or malignancies. The identification of target podocyte antigen was a critical point in the understanding of the disease: firstly in 2009 with M-type phospholipase A2 receptor (PLA2R) and then in 2014 with Thrombospondin Type 1 Domain Containing 7A (THSD7A). In the last years using an innovative approach based on laser microdissection and tandem mass spectrometry (MS/MS) has allowed the identification of new target antigen/protein as EXT1/2, NELL-1, NCAM1, SEMA3B, PCHD7, HTRA1, TGFBR3. Some of these proteins have been found in both primary and secondary MN, blurring the line between the two forms. Further studies are necessary to define and understand the clinical features of different antigen associated diseases. The aim of this review is to take a closer look at the new antigens and to evaluate how their discovery can change MN classification. Show less

The endothelial glycocalyx regulates vascular permeability, inflammation, and coagulation, and acts as a mechanosensor. The loss of glycocalyx can cause endothelial injury and contribute to several microvascular complications and, therefore, may promote diabetic retinopathy. Studies have shown a partial loss of retinal glycocalyx in diabetes, but with few molecular details of the changes in glycosaminoglycan (GAG) composition. Therefore, the purpose of our study was to investigate the effect of hyperglycemia on GAGs of the retinal endothelial glycocalyx. GAGs were isolated from rat retinal microvascular endothelial cells (RRMECs), media, and retinas, followed by liquid chromatography-mass spectrometry assays. Quantitative real-time polymerase chain reaction was used to study mRNA transcripts of the enzymes involved in GAG biosynthesis. Hyperglycemia significantly increased the shedding of heparan sulfate (HS), chondroitin sulfate (CS), and hyaluronic acid (HA). There were no changes to the levels of HS in RRMEC monolayers grown in high-glucose media, but the levels of CS and HA decreased dramatically. Similarly, while HA decreased in the retinas of diabetic rats, the total GAG and CS levels increased. Hyperglycemia in RRMECs caused a significant increase in the mRNA levels of the enzymes involved in GAG biosynthesis (including EXTL-1,2,3, EXT-1,2, ChSY-1,3, and HAS-2,3), with these increases potentially being compensatory responses to overall glycocalyx loss. Both RRMECs and retinas of diabetic rats exhibited glucose-induced alterations in the disaccharide compositions and sulfation of HS and CS, with the changes in sulfation including N,6-O-sulfation on HS and 4-O-sulfation on CS. Show less

Hepatitis B virus (HBV) related hepatocellular carcinoma (HCC) is heterogeneous and frequently contains multifocal tumors, but how the multifocal tumors relate to each other in terms of HBV integration and other genomic patterns is not clear. To interrogate heterogeneity of HBV-HCC, we developed a HBV genome enriched single cell sequencing (HGE-scSeq) procedure and a computational method to identify HBV integration sites and infer DNA copy number variations (CNVs). We performed HGE-scSeq on 269 cells from four tumor sites and two tumor thrombi of a HBV-HCC patient. HBV integrations were identified in 142 out of 269 (53%) cells sequenced, and were enriched in two HBV integration hotspots chr1:34,397,059 (CSMD2) and chr8:118,557,327 (MED30/EXT1). There were also 162 rare integration sites. HBV integration sites were enriched in DNA fragile sites and sequences around HBV integration sites were enriched for microhomologous sequences between human and HBV genomes. CNVs were inferred for each individual cell and cells were grouped into four clonal groups based on their CNVs. Cells in different clonal groups had different degrees of HBV integration heterogeneity. All of 269 cells carried chromosome 1q amplification, a recurrent feature of HCC tumors, suggesting that 1q amplification occurred before HBV integration events in this case study. Further, we performed simulation studies to demonstrate that the sequential events (HBV infecting transformed cells) could result in the observed phenotype with biologically reasonable parameters. Our HGE-scSeq data reveals high heterogeneity of HCC tumor cells in terms of both HBV integrations and CNVs. There were two HBV integration hotspots across cells, and cells from multiple tumor sites shared some HBV integration and CNV patterns. Show less

Langer-Giedion syndrome (LGS) is caused by a contiguous deletion at 8q23q24, characterized by exostoses, facial, ectodermal, and skeletal anomalies, and, occasionally, intellectual disability. LGS patients have been diagnosed clinically or by routine cytogenetic techniques, hampering the definition of an accurate genotype-phenotype correlation for the syndrome. We report two unrelated patients with 8q23q24 deletions, characterized by cytogenomic techniques, with one of them, to our knowledge, carrying the smallest deletion reported in classic LGS cases. We assessed the pathogenicity of the deletion of genes within the 8q23q24 region and reviewed other molecularly confirmed cases from the literature. Our findings suggest a 3.2-Mb critical region for a typical presentation of the syndrome, emphasizing the contribution of the TRPS1, RAD21, and EXT1 genes' haploinsufficiency, and facial dysmorphisms as well as bone anomalies as the most frequent features among patients with LGS. We also suggest a possible role for the CSMD3 gene, whose deletion seems to contribute to central nervous system anomalies. Since studies performing such correlation for LGS patients are limited, our data contribute to improving the ge-notype-phenotype characterization for LGS patients. Show less

Epithelial-mesenchymal transition (EMT) is involved in the pathophysiology of lung cancer (LC) and COPD, and the latter is an important risk factor for LC. We hypothesised that the EMT gene expression profile and signalling cascade may differ in LC patients with COPD from those with no respiratory diseases. In lung tumour specimens obtained through video-assisted thoracoscopic surgery from LC (n=20, control group) and LC-COPD patients (n=30), gene expression (quantitative real-time PCR amplification) of EMT markers Show less

The role of macrophages (Mo) and their prognostic impact in diffuse large B-cell lymphomas (DLBCL) remain controversial. By regulating the lipid metabolism, Liver-X-Receptors (LXRs) control Mo polarization/inflammatory response, and their pharmacological modulation is under clinical investigation to treat human cancers, including lymphomas. Herein, we surveyed the role of LXRs in DLBCL for prognostic purposes. Comparing bulk tumors with purified malignant and normal B-cells, we found an intriguing association of NR1H3, encoding for the LXR-α isoform, with the tumor microenvironment (TME). CIBERSORTx-based purification on large DLBCL datasets revealed a high expression of the receptor transcript in M1-like pro-inflammatory Mo. By determining an expression cut-off of NR1H3, we used digital measurement to validate its prognostic capacity on two large independent on-trial and real-world cohorts. Independently of classical prognosticators, NR1H3 Show less

The pathogenic mechanism of dilated cardiomyopathy (DCM) remains to be defined. This study aimed to identify hub genes and immune cells that could serve as potential therapeutic targets for DCM. We downloaded four datasets from the Gene Expression Omnibus (GEO) database: GSE141910, GSE3585, GSE42955 and GSE79962. Weighted gene coexpression network analysis (WGCNA) and differential expression analysis were performed to identify gene panels related to DCM. Meanwhile, the CIBERSORT algorithm was used to estimate the immune cells in DCM tissues. Multiple machine learning approaches were used to screen the hub genes and immune cells. Finally, the diagnostic value of the hub genes was assessed by receiver operating characteristic (ROC) analysis. An experimental mouse model of dilated cardiomyopathy was used to validate the bioinformatics results. FRZB and EXT1 were identified as hub biomarkers, and the ROC curves suggested an excellent diagnostic ability of the above genes for DCM. In addition, naive B cells were upregulated in DCM tissues, while eosinophils, M2 macrophages, and memory CD4 T cells were downregulated in DCM tissues. The increase in two hub genes and naive B cells was validated in animal experiments. These results indicated that FRZB and EXT1 could be used as promising biomarkers, and eosinophils, M2 macrophages, resting memory CD4 T cells and naive B cells may also affect the occurrence of DCM. Show less

Alzheimer's disease (AD) is a neurodegenerative condition that causes cognitive decline over time. Because existing diagnostic approaches for AD are limited, improving upon previously established diagnostic models based on genetic biomarkers is necessary. Firstly, four AD gene expression datasets were collected from the Gene Expression Omnibus (GEO) database. Two datasets were used to establish diagnostic models, and the other two datasets were used to verify the model effect. We merged GSE5281 with GSE44771 as the training dataset and found 120 DEGs. Then, we used random forest (RF) to screen 6 key genes (KLF15, MAFF, ITPKB, SST, DDIT4, and NRXN3) as being critical for separating AD and normal samples. The weights of these key genes were measured, and a diagnostic model was created using an artificial neural network (ANN). The area under the curve (AUC) of the model is 0.953, while the accuracy is 0.914. In the final step, two validation datasets were utilized to assess AUC performance. In GSE109887, our model had an AUC of 0.854, and in GSE132903, it had an AUC of 0.810. To summarize, we successfully identified key gene biomarkers and developed a new AD diagnostic model. Show less

The intestinal hormone, glucose-dependent insulinotropic polypeptide (GIP), is involved in important physiological functions, including postprandial blood glucose homeostasis, bone remodeling, and lipid metabolism. While mutations leading to physiological changes can be identified in large-scale sequencing, no systematic investigation of GIP missense variants has been performed. Here, we identified 168 naturally occurring missense variants in the human GIP genes from three independent cohorts comprising ~720,000 individuals. We examined amino acid changing variants scattered across the pre-pro-GIP peptide using Show less

Weight management is recommended in overweight or obese breast cancer patients, as they have an increased risk of cancer recurrence and poor prognosis. Furthermore, identifying the relationships between genetic factors and nutrition could help suggest possible individualized nutritional solutions in weight management. The objective of this pilot randomized controlled trial was to investigate the influence of two obesity-associated single nucleotide polymorphisms and the Mediterranean diet intervention on weight loss and modification of nutrient intake and metabolic parameters in overweight or obese, postmenopausal, breast cancer patients receiving adjuvant hormone therapy. Seventy-eight breast cancer patients were randomly assigned to the Mediterranean diet (MeDiet) group or control group, and seventy-one were finally analyzed. Body composition, nutrient intake, and metabolic parameters were assessed at baseline and after the 8-week intervention. Fat mass and obesity-associated ( We found that both variants did not influence weight loss or improvement of metabolic parameters within the Mediterranean diet intervention. Intake of saturated fatty acid (SFA) and trans fat was significantly increased in C carriers compared with the TT genotype of Our data suggest that considering the effects of genotype may be more necessary when the Mediterranean diet is not followed and that this diet may have a protective role against the effects of certain genotypes. Further studies are required to determine the potential mechanism of the observed gene-diet interaction. [www.ClinicalTrials.gov], identifier [NCT04045392]. Show less

Obesity plays an important role in type 2 diabetes mellitus (T2DM) and myocardial infarction (MI). Ferroptosis and ferritinophagy are related to metabolic pathways, such as fatty acid metabolism and mitochondrial respiration. We aimed to investigate the ferroptosis- and autophagy-related differentially expressed genes (DEGs) that might be potential targets for MI progression. GSE116250 was analyzed to obtain DEGs. A Venn diagram was used to obtain the overlapping ferroptosis- and autophagy-related DEGs. The enrichment pathway analysis was performed and the hub genes were obtained. Pivotal miRNAs, transcription factors, and drugs with the hub genes interactions were also predicted. The MI mice model was constructed, and qPCR analysis and single-cell sequencing were used to validate the hub genes. Utilizing the limma package and the Venn diagram, 26 ferroptosis-related and 29 autophagy-related DEGs were obtained. The list of ferroptosis-related DEGs was analyzed, which were involved in the cellular response to a toxic substance, cellular oxidant detoxification, and the IL-17 signaling pathway. The list of autophagy-related DEGs was involved in the regulation of autophagy, the regulation of JAK-STAT signaling pathway, and the regulation of MAPK cascade. In the protein-protein interaction network, the hub DEGs, such as IL-6, PTGS2, JUN, NQO1, NOS3, LEPR, NAMPT, CDKN2A, CDKN1A, and Snai1, were obtained. After validation using qPCR analysis in the MI mice model and single-cell sequencing, the 10 hub genes can be the potential targets for MI deterioration. The screened hub genes, IL-6, PTGS2, JUN, NQO1, NOS3, LEPR, NAMPT, CDKN2A, CDKN1A, and Snai1, may be therapeutic targets for patients with MI and may prevent adverse cardiovascular events. Show less

ANGPTL4, a member of the angiopoietin-like protein family, is reported to be involved in angiogenesis regulation, lipid metabolism, glucose metabolism and redox reactions, among others. Our previous study showed that the plasma ANGPTL4 level was lower in coronary atherosclerotic heart disease (CAHD) and could be a useful predictor of coronary atherosclerosis. However, the molecular mechanism underlying the function of ANGPTL4 in atherosclerosis is poorly understood. In this study, we found that overexpression of ANGPTL4 in HUVECs enhanced cell proliferation and clone-forming ability in vitro, whereas knockdown of ANGPTL4 resulted in the opposite. The expression of ANGPTL4 was upregulated in palmitic acid (PA)-treated HUVECs. Overexpression of ANGPTL4 protected against PA-induced endothelial injury. Knockdown of ANGPTL4 exacerbated the effects of PA on HUVECs. Mechanistically, we demonstrated that ANGPTL4 promoted endothelial cell proliferation through the regulation of autophagy. Knockdown of ATG7 or 3-MA (an autophagy inhibitor) attenuated the effects of ANGPTL4 on endothelial cells. The serum level of ANGPTL4 was downregulated in atherosclerosis mice. Furthermore, the expression of ANGPTL4 was correlated with autophagy-related proteins in aortic tissues of atherosclerotic mice. ANGPTL4 promotes endothelial cell proliferation and suppresses PA-induced endothelial cell injury by increasing autophagy, which may protect against the development of atherosclerosis. Show less

The amyloid cascade is the most frequently accepted hypothesis of Alzheimer's Disease (AD). According to this hypothesis, the formation of plaques precedes the appearance of fibrillary tangles. Therapeutic agents able to inhibit the formation of plaques are therefore considered as potential disease-modifying treatments (DMT) that could prevent or limit the progression of AD. Plaques are deposits formed by aggregates of amyloid-β (Aβ)-peptides. These peptides are metabolites of amyloid precursor protein (APP) first mediated by two enzymes: β-secretase 1 (BACE1) and γ-secretase. Molecular identification of these two enzymes has stimulated the development of their inhibitors. The clinical testing of these two classes of molecules has not been successful to date. The oligomerization of Aβ-peptides into plaques is now targeted by immunological approaches such as antibodies and vaccines. Structural consideration of the Aβ-peptide sequence led to the launch of the antibody Aducanumab. Several other antibodies are in late clinical phases. Progress in the understanding of the effects of N-truncated Aβ-peptides such as pE3-42, formed by the action of recently well characterized enzymes (aminopeptidase A, dipeptidylpeptidase-4 and glutaminyl cyclase) suggests that oligomerization can be limited either by enzyme inhibitors or antibody approaches. This strategy associating two structurally interconnected mechanisms is focused in this review. Show less

Lysyl-oxidase-like 3 (LOXL3) was reported to be essential in epithelial-mesenchymal transition (EMT) of cancers. However, the role of LOXL3 in hepatocellular carcinoma (HCC) remained unclear. In this study, we explored clinical significance, biological functions, and regulatory mechanisms of LOXL3 in HCC. Our study found that LOXL3 expression was markedly associated with the tumor size and clinical stage of HCC, and it was highly expressed in tumor tissues of metastatic HCC patients. High expression of LOXL3 predicted a poor prognosis of HCC. TGF-β1 treatment elevated LOXL3 protein expression and cell invasion, and reduced cell apoptosis in HCC cell lines (SMMC-7721 and Huh-7), while downregulation of LOXL3 reversed the promotive effects of TGF-β1 treatment on LOXL3 protein expression and cell invasion, and the inhibitory effect on cell apoptosis. Mechanistically, LOXL3 interacted with snail family transcriptional repressor 1 (Snail1) through STRING database and RIP assay, and Snail1 bound to ubiquitin-specific peptidase 4 (USP4) promoter by JASPAR database, luciferase reporter gene and Co-IP assays. Overexpression of USP4 reversed the inhibitory effect of LOXL3 silence on EMT in HCC cells through deubiquitinating and stabilizing the expression of Snail1. Moreover, LOXL3-promoted HCC EMT through Wnt/β-catenin/Snail1 signaling pathway. In vivo study revealed that silence of LOXL3-inhibited HCC tumor growth. In conclusion, LOXL3 silence inhibited HCC invasion and EMT through Snail1/USP4-mediated circulation loop and Wnt/β-catenin signaling pathway. Show less

Cancer stemness, defined as the self-renewal and tumor-initiation potential of cancer stem cells (CSCs), is a cancer biology property featuring activation of CSC signaling networks. Canonical WNT signaling through Frizzled and LRP5/6 receptors is transmitted to the β-catenin-TCF/LEF-dependent transcription machinery to up-regulate MYC, CCND1, LGR5, SNAI1, IFNG, CCL28, CD274 (PD-L1) and other target genes. Canonical WNT signaling causes expansion of rapidly cycling CSCs and modulates both immune surveillance and immune tolerance. In contrast, noncanonical WNT signaling through Frizzled or the ROR1/2 receptors is transmitted to phospholipase C, Rac1 and RhoA to control transcriptional outputs mediated by NFAT, AP-1 and YAP-TEAD, respectively. Noncanonical WNT signaling supports maintenance of slowly cycling, quiescent or dormant CSCs and promotes epithelial-mesenchymal transition via crosstalk with TGFβ (transforming growth factor-β) signaling cascades, while the TGFβ signaling network induces immune evasion. The WNT signaling network orchestrates the functions of cancer-associated fibroblasts, endothelial cells and immune cells in the tumor microenvironment and fine-tunes stemness in human cancers, such as breast, colorectal, gastric and lung cancers. Here, WNT-related cancer stemness features, including proliferation/dormancy plasticity, epithelial-mesenchymal plasticity and immune-landscape plasticity, will be discussed. Porcupine inhibitors, β-catenin protein-protein interaction inhibitors, β-catenin proteolysis targeting chimeras, ROR1 inhibitors and ROR1-targeted biologics are investigational drugs targeting WNT signaling cascades. Mechanisms of cancer plasticity regulated by the WNT signaling network are promising targets for therapeutic intervention; however, further understanding of context-dependent reprogramming trajectories might be necessary to optimize the clinical benefits of WNT-targeted monotherapy and applied combination therapy for patients with cancer. Show less

Long-term treatment of olanzapine, the most widely-prescribed second-generation antipsychotic, remarkably increases the risk of non-alcoholic fatty liver disease (NAFLD), whereas the mechanism for olanzapine-induced NAFLD remains unknown. Excessive hepatic fat accumulation is the basis for the pathogenesis of NAFLD, which results from the disturbance of TG metabolism in the liver. Apolipoprotein A5 (ApoA5) is a key regulator for TG metabolism in vivo that promotes TG accumulation in hepatocytes, thereby resulting in the development of NAFLD. However, there are no data indicating the role of apoA5 in olanzapine-induced NAFLD. Therefore, this study aims to investigate the role of apoA5 in olanzapine-induced NAFLD. This study was carried out via animal studies, cell experiment, and ApoA5 gene knockdown experiment. Six-week-old male C57BL/6J mice were randomized into a control group, a low-dose group, and a high-dose group, which were treated by 10% DMSO, 3 mg/(kg·d) olanzapine, and 6 mg/(kg·d) olanzapine, respectively for 8 weeks. The lipid levels in plasma, liver function indexes, and expression levels of ApoA5 were detected. HepG2 cells were treated with 0.1% DMSO (control group), 25 μmol/L olanzapine (low-dose group), 50 μmol/L olanzapine (medium-dose group), and 100 μmol/L olanzapine (high-dose group) for 24 h. HepG2 cells pretreated with 100 μmol/L olanzapine were transfected with siRNA and scrambled siRNA (negative control), respectively. We observed the changes in lipid droplets within liver tissues and cells using oil red O staining and fat deposition in liver tissues using HE staining. The mRNA and protein levels of ApoA5 were determined by real-time PCR and Western blotting, respectively. After intervention with 3 and 6 mg/(kg·d) olanzapine for 8 weeks, there was no significant difference in body weight among the 3 groups ( The short-term intervention of olanzapine does not significantly increase body weight of mice, but it can directly induce hypertriglyceridemia and NAFLD in mice. Olanzapine inhibits hepatic apoA5 secretion but does not affect hepatic apoA5 synthesis, resulting in the pathogenesis of NAFLD. Inhibition of apoA5 secretion plays a key role in the development of olanzapine-related NAFLD, which may serve as an intervention target for this disease. Show less

DNA methylation plays a significant role in transducing external environmental signals to a cellular response in reptiles; however, whether the methylation patterns are conserved across species remains unclear. Here, we examined the genome-wide DNA methylation differentiation between male and female hatchling gonads of the temperature-dependent sex determination (TSD) Mauremys mutica (M. mutica) using methylation-dependent restriction-site associated DNA sequencing (MethylRAD-seq) to test differentially methylated genes underlying sexual development. Several categories, including heat-shock genes (HSP90A, HSP30C), histone- (KDM8) and ubiquitin-related genes (TRIM39), kinases (WNK3), and gonad differentiation or gonadal-development-related genes (HSD17B8, HSD17B12), were identified as candidates for future study. Additionally, we identified several regulatory pathways potentially mediating TSD thermosensitivity such as the GnRH signaling pathway and calcium signaling pathway. These findings provide evidence that sexually dimorphic DNA methylation may be associated with sex determination or sex differentiation in TSD M. mutica. Show less

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and is clinically characterized by the impairment of memory and cognition. Accumulation of β-amyloid (Aβ) in the brain is considered as a key process in the development of AD because it impairs the synapses' function to impair memory formation. Recent research studies have indicated that a group of edible plant-derived Show less

The aim of this study was to perform familial co-segregation analysis and functional trial in vivo during mixed meal tolerance test (MMTT) of novel variants in diabetes candidate genes. It is a continuation of the project "Genetic diabetes in Lithuania" with the cohort of 1209 patients with diabetes. Prior screening for autoimmune markers confirmed type 1 diabetes (T1D) diagnosis in 88.1% (n=1065) of patients, and targeted next-generation sequencing identified 3.5% (n=42) pathogenic variants in MODY genes. Subsequently, 102 patients were classified as having diabetes of unknown etiology. 12/102 were found to have novel variants in potential diabetes genes ( MMTT analysis showed that probands with variants in Functional beta-cell study in vivo allowed to select five most probable genes for monogenic diabetes. Familial co-segregation analysis showed that novel variant in Show less

The preset neurodegenerations in Alzheimer disease (AD) are due to several mechanisms such as amyloidogenic proteolysis, neuroinflammation, mitochondrial dysfunction, neurofibrillary tangles, cholinergic dysfunction, among others. The aim of this work was to develop multitarget molecules for the treatment of AD. Therefore, a family of 64 molecules was designed based on ligand structure pharmacophores able to inhibit the activity of beta secretase (BACE1) and acetylcholinesterase (AChE) as well as to avoid amyloid beta (Aβ1-42) oligomerization. The backbone of designed molecules consisted of a trisubstituted aromatic ring, one of the substituents was a heterocyclic amine (piperidine, morpholine, pyrrolidine or N-methyl pyrrolidine) separated from the aromatic system by three carbon atoms. The set of compounds was screened in silico employing molecular docking calculations and chemoinformatic analyses. Based on Gibbs free energy of binding, binding mode and in silico predicted toxicity results, three of the best candidates were selected, synthesized, and evaluated in vitro; F3S4-m, F2S4-m, and F2S4-p. All three compounds prevented Aβ1-42 aggregation (F3S4-m in 30.5%, F2S4-p in 42.1%, and F2S4-m in 60.9%). Additionally, inhibitory activity against AChE (ki 0.40 μM and 0.19 μM) and BACE1 (IC50 15.97 μM and 8.38 μM) was also observed for compounds F2S4-m and F3S4-m, respectively. Despite the BACE IC50 results demonstrated that all compounds are very less potent respect to peptidomimetic inhibitor (PI-IV IC50 3.20 nM), we can still say that F3S4-m is capable to inhibit AChE and BACE1. Show less

Directed evolution is a widely-used engineering strategy for improving the stabilities or biochemical functions of proteins by repeated rounds of mutation and selection. A protein of interest is selected as the template and expressed on a molecular display platform such as a bacteriophage for engineering. Initially, the surface-displayed protein template needs to be checked against the desired target Show less

NALCN channel mediates sodium leak currents and is important for maintaining proper resting membrane potential. NALCN and FAM155A form the core complex of the channel, the activity of which essentially depends on the presence of both UNC79 and UNC80, two auxiliary proteins. NALCN, FAM155A, UNC79, and UNC80 co-assemble into a large hetero-tetrameric channel complex. Genetic mutations of NALCN channel components lead to neurodevelopmental diseases. However, the structure and mechanism of the intact channel complex remain elusive. Here, we present the cryo-EM structure of the mammalian NALCN-FAM155A-UNC79-UNC80 quaternary complex. The structure shows that UNC79-UNC80 form a large piler-shaped heterodimer which was tethered to the intracellular side of the NALCN channel through tripartite interactions with the cytoplasmic loops of NALCN. Two interactions are essential for proper cell surface localization of NALCN. The other interaction relieves the self-inhibition of NALCN by pulling the auto-inhibitory CTD Interacting Helix (CIH) out of its binding site. Our work defines the structural mechanism of NALCN modulation by UNC79 and UNC80. Show less

It is considered that brain ischemia can be causative connected to Alzheimer's disease. In the CA1 and CA3 regions of the hippocampus and temporal cortex, genes related to Alzheimer's disease, such as the Show less

We propose a model to explain the pathogenesis of Alzheimer's disease (AD) based on the theory that any disease affecting a healthy organism originates from a bistable feedback loop that shifts the system from a physiological to a pathological condition. We focused on the known double inhibitory loop involving the cellular prion protein (PrPC) and the enzyme BACE1 that produces amyloid-beta (Aβ) peptides. BACE1 is inhibited by PrPC, but its inhibitory activity is lost when PrPC binds to Aβ oligomers (Aβo). Excessive Aβo formation would switch the loop to a pathogenic condition involving the Aβo-PrPC-mGluR5 complex, Fyn kinase activation, tau, and NMDAR phosphorylation, ultimately leading to neurodegeneration. Based on the emerging role of cyclic nucleotides in Aβ production, and thereby in synaptic plasticity and cognitive processes, cAMP and cGMP can be considered as modulatory factors capable of inducing the transition from a physiological steady state to a pathogenic one. This would imply that critical pharmacological targets for AD treatment lie within pathways that lead to an imbalance of cyclic nucleotides in neurons. If this hypothesis is confirmed, it will provide precise indications for the development of preventive or therapeutic treatments for the disease. Show less

We previously identified four Alzheimer's disease (AD) subgroups with increasingly higher cerebrospinal fluid (CSF) levels of tau phosphorylated at threonine 181 (p-tau). These subgroups included individuals across the cognitive spectrum, suggesting p-tau subgroups could reflect distinct biological changes in AD, rather than disease severity. Therefore, in the current study, we further investigated which potential processes may be related with p-tau subgroups, by comparing individuals on CSF markers for presynaptic structure [vesicle-associated membrane protein 2 (VAMP2)], postsynaptic structure [neurogranin (NRGN)], axonal damage [neurofilament light (NfL)], and amyloid production [beta-secretase 1 (BACE1) and amyloid-beta 1-40 (Aβ40)]. We selected 348 amyloid-positive (A+) individuals (53 preclinical, 102 prodromal, 193 AD dementia) and 112 amyloid-negative (A-) cognitively normal (CN) individuals from the Amsterdam Dementia Cohort (ADC). Individuals were labeled according to their p-tau subgroup (subgroup 1: p-tau ≤ 56 pg/ml; subgroup 2: 57-96 pg/ml; subgroup 3: 97-159 pg/ml; subgroup 4: > 159 pg/ml). CSF protein levels were measured with ELISA (NRGN, BACE1, Aβ40, NfL) or single-molecule array (Simoa) (VAMP2). We tested whether protein levels differed between the p-tau subgroups within A+ individuals with linear models corrected for age and sex and whether disease stage influenced these relationships. Among A+ individuals, higher p-tau subgroups showed a higher percentage of AD dementia [subgroup 1: n = 41/94 (44%); subgroup 2: n = 81/147 (55%); subgroup 3: n = 59/89 (66%); subgroup 4: n = 7/11 (64%)]. Relative to controls, subgroup 1 showed reduced CSF levels of BACE1, Aβ40, and VAMP2 and higher levels of NfL. Subgroups 2 to 4 showed gradually increased CSF levels of all measured proteins, either across the first three (NfL and Aβ40) or across all subgroups (VAMP2, NRGN, BACE1). The associations did not depend on the clinical stage (interaction p-values ranging between 0.19 and 0.87). The results suggest that biological heterogeneity in p-tau levels in AD is related to amyloid metabolism and synaptic integrity independent of clinical stage. Biomarkers reflecting amyloid metabolism and synaptic integrity may be useful outcome measures in clinical trials targeting tau pathology. Show less

Abnormal accumulation of β-amyloid (Aβ) peptides is a culprit in Alzheimer's disease (AD); blocking Aβ generation is therefore being explored as a logical approach for AD treatment. Here, we demonstrate that targeted inhibition of β-site amyloid precursor protein (APP) cleaving enzyme-1 (BACE-1) in microglia has unique advantages. When Show less

Early feeding regime has a substantial lifelong effect on lambs and weaning ewe's milk can lead to the intestinal injury of lambs. To explore the molecular regulatory mechanism of intestinal injury of lambs under weaning stress, the jejunum was conducted transcriptome and then integrated analyzed with our previous proteome data. A total of 255 upregulated genes and 285 downregulated genes were significantly identified. These genes showed low overlapping with differentially expressed proteins identified by isobaric tags for relative and absolute quantification (iTRAQ). However, according to their functions, the differentially expressed genes (DEGs) and proteins with the same expression trend were enriched for the similar Gene Ontology (GO) terms and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, such as intestinal lipid absorption, urea cycle, peroxisome proliferator-activated receptor (PPAR) signaling pathway, and ferroptosis. Furthermore, the DEGs, including Show less

In Alzheimer's disease (AD), the accumulation of amyloid-β plaques, overactivity of MAO-B, and phosphorylated tau protein in the central nervous system result in neuroinflammation and cognitive impairments. Therefore, the multi-targeting of these therapeutic targets has emerged as a promising strategy for the development of AD treatments. The current study reports the isolation and identification of seven amide alkaloids, namely, Show less

Complex neurological disorders, including Alzheimer's disease, are one of the major therapeutic areas to which multitarget drug discovery strategies have been applied in the last twenty years. Due to the complex multifactorial etiopathogenesis of Alzheimer's disease, it has been proposed that to be successful the pharmaceutical agents should act on multiple targets in order to restore the complex disease network and to provide disease modifying effects. Here we report on the synthesis and the anticholinergic activity profiles of seven multitarget anti-Alzheimer compounds designed by combining galantamine, a well-known acetylcholinesterase inhibitor, with different peptide fragments endowed with inhibitory activity against BACE-1. A complementary approach based on molecular docking simulations of the galantamine-peptide derivatives in the active sites of acetylcholinesterase and of the related butyrylcholinesterase, as well as on inhibition kinetics, by global fitting of the reaction progress curves, allowed to gain insights into the enzyme-inhibitor mechanism of interaction. The resulting structure-activity relationships pave the way towards the design of more effective pharmacodynamic/pharmacokinetic multitarget inhibitors. Show less