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The medial prefrontal cortex (mPFC) is a key brain structure for higher cognitive functions such as decision-making and goal-directed behavior, many of which require awareness of spatial variables including one's current position within the surrounding environment. Although previous studies have reported spatially tuned activities in mPFC during memory-related trajectory, the spatial tuning of mPFC network during freely foraging behavior remains elusive. Here, we reveal geometric border or border-proximal representations from the neural activity of mPFC ensembles during naturally exploring behavior, with both allocentric and egocentric boundary responses. Unlike most of classical border cells in the medial entorhinal cortex (MEC) discharging along a single wall, a large majority of border cells in mPFC fire particularly along four walls. mPFC border cells generate new firing fields to external insert, and remain stable under darkness, across distinct shapes, and in novel environments. In contrast to hippocampal theta entrainment during spatial working memory tasks, mPFC border cells rarely exhibited theta rhythmicity during spontaneous locomotion behavior. These findings reveal spatially modulated activity in mPFC, supporting local computation for cognitive functions involving spatial context and contributing to a broad spatial tuning property of cortical circuits.
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Córtex Pré-Frontal , Ritmo Teta , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/citologia , Animais , Ritmo Teta/fisiologia , Masculino , Camundongos , Córtex Entorrinal/fisiologia , Neurônios/fisiologia , Hipocampo/fisiologia , Memória Espacial/fisiologia , Camundongos Endogâmicos C57BL , Memória de Curto Prazo/fisiologiaRESUMO
NADH cytochrome b5 oxidoreductase (Ncb5or) is a cytosolic ferric reductase implicated in diabetes and neurological conditions. Ncb5or comprises cytochrome b5 (b5 ) and cytochrome b5 reductase (b5 R) domains separated by a CHORD-Sgt1 (CS) linker domain. Ncb5or redox activity depends on proper inter-domain interactions to mediate electron transfer from NADH or NADPH via FAD to heme. While full-length human Ncb5or has proven resistant to crystallization, we have succeeded in obtaining high-resolution atomic structures of the b5 domain and a construct containing the CS and b5 R domains (CS/b5 R). Ncb5or also contains an N-terminal intrinsically disordered region of 50 residues that has no homologs in other protein families in animals but features a distinctive, conserved L34 MDWIRL40 motif also present in reduced lateral root formation (RLF) protein in rice and increased recombination center 21 in baker's yeast, all attaching to a b5 domain. After unsuccessful attempts at crystallizing a human Ncb5or construct comprising the N-terminal region naturally fused to the b5 domain, we were able to obtain a high-resolution atomic structure of a recombinant rice RLF construct corresponding to residues 25-129 of human Ncb5or (52% sequence identity; 74% similarity). The structure reveals Trp120 (corresponding to invariant Trp37 in Ncb5or) to be part of an 11-residue α-helix (S116 QMDWLKLTRT126 ) packing against two of the four helices in the b5 domain that surround heme (α2 and α5). The Trp120 side chain forms a network of interactions with the side chains of four highly conserved residues corresponding to Tyr85 and Tyr88 (α2), Cys124 (α5), and Leu47 in Ncb5or. Circular dichroism measurements of human Ncb5or fragments further support a key role of Trp37 in nucleating the formation of the N-terminal helix, whose location in the N/b5 module suggests a role in regulating the function of this multi-domain redox enzyme. This study revealed for the first time an ancient origin of a helical motif in the N/b5 module as reflected by its existence in a class of cytochrome b5 proteins from three kingdoms among eukaryotes.
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Citocromos b , NAD , Animais , Humanos , Citocromo-B(5) Redutase/química , Oxirredutases , Heme/químicaRESUMO
BACKGROUND: The comorbidity between schizophrenia (SCZ) and inflammatory bowel disease (IBD) observed in epidemiological studies is partially attributed to genetic overlap, but the magnitude of shared genetic components and the causality relationship between them remains unclear. METHODS: By leveraging large-scale genome-wide association study (GWAS) summary statistics for SCZ, IBD, ulcerative colitis (UC), and Crohn's disease (CD), we conducted a comprehensive genetic pleiotropic analysis to uncover shared loci, genes, or biological processes between SCZ and each of IBD, UC, and CD, independently. Univariable and multivariable Mendelian randomization (MR) analyses were applied to assess the causality across these two disorders. RESULTS: SCZ genetically correlated with IBD (rg = 0.14, p = 3.65 × 10−9), UC (rg = 0.15, p = 4.88 × 10−8), and CD (rg = 0.12, p = 2.27 × 10−6), all surpassed the Bonferroni correction. Cross-trait meta-analysis identified 64, 52, and 66 significantly independent loci associated with SCZ and IBD, UC, and CD, respectively. Follow-up gene-based analysis found 11 novel pleiotropic genes (KAT5, RABEP1, ELP5, CSNK1G1, etc) in all joint phenotypes. Co-expression and pathway enrichment analysis illustrated those novel genes were mainly involved in core immune-related signal transduction and cerebral disorder-related pathways. In univariable MR, genetic predisposition to SCZ was associated with an increased risk of IBD (OR 1.11, 95% CI 1.071.15, p = 1.85 × 10−6). Multivariable MR indicated a causal effect of genetic liability to SCZ on IBD risk independent of Actinobacteria (OR 1.11, 95% CI 1.061.16, p = 1.34 × 10−6) or BMI (OR 1.11, 95% CI 1.041.18, p = 1.84 × 10−3). CONCLUSIONS: We confirmed a shared genetic basis, pleiotropic loci/genes, and causal relationship between SCZ and IBD, providing novel insights into the biological mechanism and therapeutic targets underlying these two disorders.
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In clinical practice, depression and anxiety frequently coexist, and they are both comorbid with somatic diseases. The P2X7R is an adenosine 5'-triphosphate (ATP)-gated non-selective cation channel that is widely expressed in immune-related cells. Under conditions of stress, chronic pain, and comorbid chronic physical illness, P2X7R activation in glial cells leads to neuroinflammation. This could contribute to the development of anxiety and depression-related emotional disturbances. Previous studies have shown that the P2X7 receptor (P2X7R) plays an important role in the pathogenesis of both anxiety and depression. Thus, the P2X7R may play a role in the comorbidity of anxiety and depression. Positron emission tomography can be used to assess the degree and location of neuroinflammation by monitoring functional and expression-related changes in P2X7R, which can facilitate clinical diagnoses and guide the treatment of patients with anxiety and depression. Moreover, single nucleotide polymorphisms (SNPs) in the P2X7R gene are associated with susceptibility to different types of psychiatric disorders. Thus, evaluating the SNPs of the P2X7R gene could enable personalized mood disorder diagnoses and treatments. If the P2X7R were set as a therapeutic target, selective P2X7R antagonists may modulate P2X7R function, thereby altering the balance of intra- and extra-cellular ATP. This could have therapeutic implications for treating anxiety and depression, as well as for pain management. According to in vitro and in vivo studies, the P2X7R plays an important role in anxiety and depression. In this review, we consider the potential of the P2X7R as a therapeutic target for comorbid anxiety and depression, and discuss the potential diagnostic and therapeutic value of this receptor.
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BACKGROUND: Predicting the long-term survival in adenoid cystic carcinoma (ACC) patients remains challenging. Inflammatory cell-based indices are emerging as prognostic indicators of oncology. PURPOSE: This study aimed to determine the associations between the preoperative systemic inflammatory response index (SIRI) and the systemic immunoinflammatory index (SII) and the 10-year survival rates in patients with ACC of the head and neck (ACCHN). STUDY DESIGN, SETTING, SAMPLE: This retrospective cohort study comprised ACCHN patients treated at the Chinese People's Liberation Army General Hospital between November 2003 and December 2020. PREDICTOR VARIABLE: The inflammatory response, assessed using the SIRI and SII, was the predictor variable. The optimal cutoff values were based on the maximum Youden index values (sensitivity ï¼ specificityï¼1). The patients were divided into two groups each, based on the SIRI (low, ≤ 0.15) and (high, > 0.15), and SII (low, ≤ 562.8 and high, > 562.8) values. MAIN OUTCOME VARIABLE(S): Overall survival (OS), or the number of days, weeks, or months between treatment initiation and death (or the last follow-up date), was the primary outcome variable. COVARIATES: The covariates were classified as demographic (age, gender, body mass index), medical (hypertension, diabetes), inflammatory (neutrophils, lymphocytes, monocytes, platelets, lymphocyte-monocyte ratio, platelet-lymphocyte ratio, neutrophil-lymphocyte ratio), and perioperative (tumor stage, lymph node metastasis, tumor size, treatment type). ANALYSES: Descriptive, univariate, and multivariate Cox proportional risk regression analyses were performed to determine whether the SIRI and SII were independent prognostic factors for OS. Kaplan-Meier survival curves and log-rank tests were used to determine their associations with the OS. RESULTS: The study sample comprised 162 patients (mean age, 52 ± 14; males, 39.5%). The median follow-up time was 6.81 ± 0.23, and the 10-year OS rate was 7.68 ± 0.25. The low and high SIRI groups comprised 109 and 53 patients, while the low and high SII groups comprised 116 and 46 patients, respectively. SIRI was identified as a prognostic factor (P < .01; hazard ratio, 2.45; 95% confidence interval, 1.35-4.45). CONCLUSION AND RELEVANCE: The SIRI has the advantages of reproducibility, convenience, noninvasiveness, and affordability, making it a promising prognostic inflammatory index for patients with ACCHN.
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Carcinoma Adenoide Cístico , Humanos , Masculino , Feminino , Carcinoma Adenoide Cístico/mortalidade , Carcinoma Adenoide Cístico/patologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Taxa de Sobrevida , Adulto , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/imunologia , Prognóstico , IdosoRESUMO
The current study involved the preparation of a number of MnOx/Sep catalysts using the impregnation (MnOx/Sep-I), hydrothermal (MnOx/Sep-H), and precipitation (MnOx/Sep-P) methods. The MnOx/Sep catalysts that were produced were examined for their ability to catalytically oxidize formaldehyde (HCHO). Through the use of several technologies, including N2 adsorption-desorption, XRD, FTIR, TEM, H2-TPR, O2-TPD, CO2-TPD, and XPS, the function of MnOx in HCHO elimination was examined. The MnOx/Sep-H combination was shown to have superior catalytic activities, outstanding cycle stability, and long-term activity. It was also able to perform complete HCHO conversion at 85 °C with a high GHSV of 6000 mL/(g·h) and 50% humidity. Large specific surface area and pore size, a widely dispersed active component, a high percentage of Mn3+ species, and lattice oxygen concentration all suggested a potential reaction route for HCHO oxidation. This research produced a low-cost, highly effective catalyst for HCHO purification in indoor or industrial air environments.
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Platinum-based supported intermetallic alloys (IMAs) demonstrate exceptional performance in catalytic propane dehydrogenation (PDH) primarily because of their remarkable resistance to coke formation. However, these IMAs still encounter a significant hurdle in the form of catalyst deactivation. Understanding the complex deactivation mechanism of supported IMAs, which goes beyond conventional coke deposition, requires meticulous microscopic structural elucidation. In this study, we unravel a nonclassical deactivation mechanism over a PtZn/γ-Al2O3 PDH catalyst, dictated by the PtZn to Pt3Zn nanophase transformation accompanied with dezincification. The physical origin lies in the metal support interaction (MSI) that enables strong chemical bonding between hydroxyl groups on the support and Zn sites on the PtZn phase to selectively remove Zn species followed by the reconstruction towards Pt3Zn phase. Building on these insights, we have devised a solution to circumvent the deactivation by passivating the MSI through surface modification of γ-Al2O3 support. By exchanging protons of hydroxyl groups with potassium ions (K) on the γ-Al2O3 support, such a strategy significantly minimizes the dezincification of PtZn IMA via diminished metal-support bonding, which dramatically reduces the deactivation rate from 0.2044 to 0.0587 h-1.
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BACKGROUND: Effective risk prediction models are lacking for personalized endoscopic screening of gastric cancer (GC). We aimed to develop, validate, and evaluate a questionnaire-based GC risk assessment tool for risk prediction and stratification in the Chinese population. METHODS: In this three-stage multicenter study, we first selected eligible variables by Cox regression models and constructed a GC risk score (GCRS) based on regression coefficients in 416,343 subjects (aged 40-75 years) from the China Kadoorie Biobank (CKB, development cohort). In the same age range, we validated the GCRS effectiveness in 13,982 subjects from another independent Changzhou cohort (validation cohort) as well as in 5348 subjects from an endoscopy screening program in Yangzhou. Finally, we categorized participants into low (bottom 20%), intermediate (20-80%), and high risk (top 20%) groups by the GCRS distribution in the development cohort. RESULTS: The GCRS using 11 questionnaire-based variables demonstrated a Harrell's C-index of 0.754 (95% CI, 0.745-0.762) and 0.736 (95% CI, 0.710-0.761) in the two cohorts, respectively. In the validation cohort, the 10-year risk was 0.34%, 1.05%, and 4.32% for individuals with a low (≤ 13.6), intermediate (13.7~30.6), and high (≥ 30.7) GCRS, respectively. In the endoscopic screening program, the detection rate of GC varied from 0.00% in low-GCRS individuals, 0.27% with intermediate GCRS, to 2.59% with high GCRS. A proportion of 81.6% of all GC cases was identified from the high-GCRS group, which represented 28.9% of all the screened participants. CONCLUSIONS: The GCRS can be an effective risk assessment tool for tailored endoscopic screening of GC in China. Risk Evaluation for Stomach Cancer by Yourself (RESCUE), an online tool was developed to aid the use of GCRS.
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Neoplasias Gástricas , Humanos , Detecção Precoce de Câncer , População do Leste Asiático , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/epidemiologia , Adulto , Pessoa de Meia-Idade , IdosoRESUMO
OBJECTIVE: We aimed to identify key susceptibility gene targets in multiple datasets generated from postmortem brains and blood of Parkinson's disease (PD) patients and healthy controls (HC). METHODS: We performed a multitiered analysis to integrate the gene expression data using multiple-gene chips from 244 human postmortem tissues. We identified hub node genes in the highly PD-related consensus module by constructing protein-protein interaction (PPI) networks. Next, we validated the top four interacting genes in 238 subjects (90 sporadic PD, 125 HC and 23 Parkinson's Plus Syndrome (PPS)). Utilizing multinomial logistic regression analysis (MLRA) and receiver operating characteristic (ROC), we analyzed the risk factors and diagnostic power for discriminating PD from HC and PPS. RESULTS: We identified 1333 genes that were significantly different between PD and HCs based on seven microarray datasets. The identified MEturquoise module is related to synaptic vesicle trafficking (SVT) dysfunction in PD (P < 0.05), and PPI analysis revealed that SVT genes PPP2CA, SYNJ1, NSF and PPP3CB were the top four hub node genes in MEturquoise (P < 0.001). The levels of these four genes in PD postmortem brains were lower than those in HC brains. We found lower blood levels of PPP2CA, SYNJ1 and NSF in PD compared with HC, and lower SYNJ1 in PD compared with PPS (P < 0.05). SYNJ1, negatively correlated to PD severity, displayed an excellent power to discriminating PD from HC and PPS. CONCLUSIONS: This study highlights that SVT genes, especially SYNJ1, may be promising markers in discriminating PD from HCs and PPS.
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Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Proteínas do Tecido Nervoso , Doença de Parkinson , Mapas de Interação de Proteínas , Vesículas Sinápticas , Autopsia , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Vesículas Sinápticas/genética , Vesículas Sinápticas/metabolismoRESUMO
Marine cyanobacteria contribute to approximately half of the ocean primary production, and their biomass is limited by low iron (Fe) bioavailability in many regions of the open seas. The mechanisms by which marine cyanobacteria overcome Fe limitation remain unclear. In this study, multiple Fe uptake pathways have been identified in a coastal strain of Synechococcus sp. strain PCC 7002. A total of 49 mutants were obtained by gene knockout methods, and 10 mutants were found to have significantly decreased growth rates compared to the wild type (WT). The genes related to active Fe transport pathways such as TonB-dependent transporters and the synthesis and secretion of siderophores are found to be essential for the adaptation of Fe limitation in Synechococcus sp. PCC 7002. By comparing the Fe uptake pathways of this coastal strain with other open-ocean cyanobacterial strains, it can be concluded that the Fe uptake strategies from different cyanobacteria have a strong relationship with the Fe bioavailability in their habitats. The evolution and adaptation of cyanobacterial iron acquisition strategies with the change of iron environments from ancient oceans to modern oceans are discussed. This study provides new insights into the diversified strategies of marine cyanobacteria in different habitats from temporal and spatial scales. IMPORTANCE Iron (Fe) is an important limiting factor of marine primary productivity. Cyanobacteria, the oldest photosynthetic oxygen-evolving organisms on the earth, play crucial roles in marine primary productivity, especially in the oligotrophic ocean. How they overcome Fe limitation during the long-term evolution process has not been fully revealed. Fe uptake mechanisms of cyanobacteria have been partially studied in freshwater cyanobacteria but are largely unknown in marine cyanobacterial species. In this paper, the characteristics of Fe uptake mechanisms in a coastal model cyanobacterium, Synechococcus sp. PCC 7002, were studied. Furthermore, the relationship between Fe uptake strategies and Fe environments of cyanobacterial habitats has been revealed from temporal and spatial scales, which provides a good case for marine microorganisms adapting to changes in the marine environment.
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Ferro , Synechococcus , Ferro/metabolismo , Synechococcus/genética , Synechococcus/metabolismo , Transporte Biológico , Sideróforos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismoRESUMO
Tenomodulin (Tnmd) is a type II transmembrane glycoprotein that regulates tendon development and maturation. Our previous study indicated that mechanical stretch could induce Tnmd expression to promote tenocyte migration, associated with reinforcement of fibrous actin (F-actin) stress fibers and chromatin decondensation. However, the detailed molecular mechanisms of this processes are far from clear. Activation of mitogen-activated protein kinase (MAPK) signaling occurs in response to various extracellular stimuli and controls a large number of fundamental cellular processes. The present study we investigated the influence of MAPK signaling on mechanical stretch-induced Tnmd expression and its action way. Expression and activities of extracellular signal-related kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinases (JNK) and p38 MAPK (p38) were determined by Western blot. Cell migration was detected by Transwell assay. Immunofluorescence staining was used to detect F-actin stress fibers. Nuclear chromatin decondensation was detected by in situ DNaseI sensitivity assay. It was found that mechanical stretch promoted Tnmd expression by activating ERK1/2, JNK and p38 signaling. The inhibition of the ERK1/2, JNK or p38 repressed mechanical stretch-promoted tenocyte migration and mechanical stretch-induced reinforcement of F-actin stress fibers. However, only ERK1/2 and p38 inhibitor could repress mechanical stretch-induced chromatin decondensation, and the JNK inhibitor had no significant effect. Moreover, latrunculin (Lat A), the most widely used reagent to depolymerize actin filaments, could inhibit the stretch-induced chromatin decondensation. Taken together, our findings elucidated a molecular pathway by which a mechanical signal is transduced via activation of MAPK signaling to influence reinforcement of F-actin stress fibers and chromatin decondensation, which could further lead Tnmd expression to promote tenocyte migration.
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Actinas , Tenócitos , Actinas/metabolismo , Células Cultivadas , Cromatina , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Transdução de Sinais/fisiologia , Estresse Mecânico , Tenócitos/metabolismo , Animais , RatosRESUMO
Chronic neutrophilic leukemia (CNL) is a rare type of myeloproliferative neoplasm (MPN). Due to its nonspecific clinical symptoms and lack of specific molecular markers, it was previously difficult to distinguish it from other diseases with increased neutrophils. However, the discovery of the CSF3R mutation in CNL 10 years ago and the update of the diagnostic criteria by the World Health Organization (WHO) in 2016 brought CNL into a new era of molecular diagnosis. Next-generation sequencing (NGS) technology has led to the identification of numerous mutant genes in CNL. While CSF3R is commonly recognized as the driver mutation of CNL, other mutations have also been detected in CNL using NGS, including mutations in other signaling pathway genes (CBL, JAK2, NARS, PTPN11) and chromatin modification genes (ASXL1, SETBP1, EZH2), DNA methylation genes (DNMT3A, TET2), myeloid-related transcription factor genes (RUNX1, GATA2), and splicing and RNA metabolism genes (SRSF2, U2AF1). The coexistence of these mutated genes and CSF3R mutations, as well as the different evolutionary sequences of clones, deepens the complexity of CNL molecular biology. The purpose of this review is to summarize the genetic research findings of CNL in the last decade, focusing on the common mutated genes in CNL and their clinical significance, as well as the clonal evolution pattern and sequence of mutation acquisition in CNL, to provide a basis for the appropriate management of CNL patients.
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Myc is a pivotal protooncogenic transcription factor that contributes to the development of almost all Burkitt's lymphomas and about one-third of diffuse large B-cell lymphomas. How B-cells sustain their uncontrolled proliferation due to high Myc is not yet well defined. Here, we found that Myc trans-represses the expression of murine LAPTM5, a gene coding a lysosome-associated protein, by binding to two E-boxes in the LAPTM5 promoter. While the product of intact mRNA (CDS+3'UTR) of LAPTM5 failed to suppress the growth of B-lymphomas, either the protein coded by coding sequence (CDS) itself or the non-coding 3'-untranslated region (3'UTR) mRNA was able to inhibit the growth of B-lymphomas. Moreover, Myc trans-activated miR-17-3p, which promoted tumor growth. Strikingly, LAPTM5 3'UTR contains 11 miR-17-3p-binding sites through which the LAPTM5 protein synthesis was inhibited. The functional interplay between low LAPTM5 mRNA and high miR-17-3p due to high Myc in B-lymphomas leads to further dampening of tumor-suppressive LAPTM5 protein, which promotes tumor progression. Our results indicate that Myc inhibits LAPTM5 expression in B-lymphoma cells by transcriptional and post-transcriptional modifications.
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Linfoma de Burkitt , Linfoma Difuso de Grandes Células B , MicroRNAs , Humanos , Animais , Camundongos , Regiões 3' não Traduzidas/genética , Linfoma de Burkitt/metabolismo , Fatores de Transcrição/genética , Linfoma Difuso de Grandes Células B/genética , MicroRNAs/genética , Proteínas de Membrana/genéticaRESUMO
BACKGROUND: Type 2 diabetes mellitus (T2DM) induced diabetes-associated cognitive dysfunction (DACD) that seriously affects the self-management of T2DM patients, is currently one of the most severe T2DM-associated complications, but the mechanistic basis remains unclear. Mitochondria are highly dynamic organelles, whose function refers to a broad spectrum of features such as mitochondrial dynamics, mitophagy and so on. Mitochondrial abnormalities have emerged as key determinants for cognitive function, the relationship between DACD and mitochondria is not well understood. METHODS: Here, we explored the underlying mechanism of mitochondrial dysfunction of T2DM mice and HT22 cells treated with high glucose/palmitic acid (HG/Pal) focusing on the mitochondrial fission-mitophagy axis with drug injection, western blotting, Immunofluorescence, and electron microscopy. We further explored the potential role of caveolin-1 (cav-1) in T2DM induced mitochondrial dysfunction and synaptic alteration through viral transduction. RESULTS: As previously reported, T2DM condition significantly prompted hippocampal mitochondrial fission, whereas mitophagy was blocked rather than increasing, which was accompanied by dysfunctional mitochondria and impaired neuronal function. By contrast, Mdivi-1 (mitochondrial division inhibitor) and urolithin A (mitophagy activator) ameliorated mitochondrial and neuronal function and thereafter lead to cognitive improvement by inhibiting excessive mitochondrial fission and giving rise to mitophagy, respectively. We have previously shown that cav-1 can significantly improve DACD by inhibiting ferroptosis. Here, we further demonstrated that cav-1 could not only inhibit mitochondrial fission via the interaction with GSK3ß to modulate Drp1 pathway, but also rescue mitophagy through interacting with AMPK to activate PINK1/Parkin and ULK1-dependent signlings. CONCLUSIONS: Overall, our data for the first time point to a mitochondrial fission-mitophagy axis as a driver of neuronal dysfunction in a phenotype that was exaggerated by T2DM, and the protective role of cav-1 in DACD. Graphic Summary Illustration. In T2DM, excessive mitochondrial fission and impaired mitophagy conspire to an altered mitochondrial morphology and mitochondrial dysfunction, with a consequent neuronal damage, overall suggesting an unbalanced mitochondrial fission-mitophagy axis. Upon cav-1 overexpression, GSK3ß and AMPK are phosphorylated respectively to activate Drp1 and mitophagy-related pathways (PINK1 and ULKI), ultimately inhibits mitochondrial fission and enhances mitophagy. In the meantime, the mitochondrial morphology and neuronal function are rescued, indicating the protective role of cav-1 on mitochondrial fission-mitophagy axis. Video Abstract.
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Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Doenças Mitocondriais , Humanos , Camundongos , Animais , Mitofagia , Dinâmica Mitocondrial/genética , Diabetes Mellitus Tipo 2/complicações , Caveolina 1/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Neurônios/metabolismo , Disfunção Cognitiva/etiologia , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The basic research indicated that microglial P2Y12 receptors (P2Y12Rs) are involved in the pathophysiology of epilepsy through regulated microglial-neuronal interactions, aberrant neurogenesis, or immature neuronal projections. However, whether the clinic case of epilepsy would be associated with P2Y12 receptor gene polymorphisms is presented with few data. In our study, a total of 176 patients with epilepsy and 50 healthy controls were enrolled. Two single-nucleotide polymorphisms, namely rs1491974 and rs6798347, were selected for analysis. The results revealed that carriers of the G allele of rs1491974 G>A or rs6798347 G>A may be associated with an increased risk of epilepsy (OR = 0.576, 95% CI = 0.368-0.901, p = 0.015; OR = 0.603, 95% CI = 0.367-0.988, p = 0.043). Interestingly, we found that the rs1491974 G>A genotype and allele frequencies have only a significant difference in female instead of male case (p = 0.004 for genotype; p = 0.001 for allele). The subgroup analysis demonstrated that individuals with the rs1491974 G>A genotype might have more frequent seizure (OR = 0.476, 95% CI = 0.255-0.890; p = 0.019). These data implied that both rs1491974 and rs6798347 polymorphisms of P2Y12R would be able to play import roles in epilepsy susceptibility, whereas the rs1491974 polymorphism may be specifically related to seizure frequency.
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Epilepsia , Antagonistas do Receptor Purinérgico P2Y , Humanos , Masculino , Feminino , Genótipo , Polimorfismo de Nucleotídeo Único , Frequência do Gene , Convulsões/complicações , Receptores Purinérgicos P2Y12RESUMO
This study aimed to dig new molecular mechanisms and medications for age-related hearing loss (ARHL or presbycusis) by extracting common results of publicly available datasets. Based on five datasets (GSE153882, GSE121856, GSE98070, GSE45026, and GSE98071) in studies of cochlear hair cells, we explored the interrelationships among presbycusis-related genes, including gene interactions, enrichment analysis, miRNA-mRNA matching pairs, and potential new drugs. Together, there were 25 common increased mRNAs. A total of 183 drugs can simultaneously target 11 of these mRNAs. In the interaction network, hub genes included: Cbln1, Prl, Mpp6 and Gh. Meanwhile, there were 74 common decreased mRNAs. The hub genes include Cdkn1a, Egr1, and Ctgf. After de-duplication, the 25 common increased mRNAs had 946 matched miRNAs, with 34 decreased ones; and the 74 decreased mRNAs had 1164 matched miRNAs, with 26 increased ones. Between the inhibitors of increased mRNAs and enhancers of decreased mRNAs, there were 26 common drugs. Besides, we discovered six key genes that may play a crucial role in the onset of presbycusis. In conclusion, by jointly analyzing multiple datasets, we found 25 common increased mRNAs (e.g., Cbln1, Prl, Mpp6 and Gh) and 74 common decreased mRNAs (Cdkn1a, Egr1, and Ctgf), as well as 34 potential therapeutic miRNAs and 26 pathogenic miRNAs, and three candidate drugs (calcitriol, diclofenac, and diethylstilbestrol). They may provide new targets and strategies for mechanistic and therapeutic studies in ARHL.
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MicroRNAs , Presbiacusia , Animais , Camundongos , Presbiacusia/genética , Perfilação da Expressão Gênica , Células Ciliadas Auditivas , Calcitriol , Fator de Crescimento do Tecido Conjuntivo , MicroRNAs/genética , RNA Mensageiro/genéticaRESUMO
BACKGROUND: Sleep loss and its associated conditions (e.g. cognitive deficits) represent a large societal burden, but the underlying mechanisms of these cognitive deficits remain unknown. This study assessed the effect of dexmedetomidine (DEX) on cognitive decline induced by sleep loss. METHODS: C57BL/6 mice were subjected to chronic sleep restriction (CSR) for 20 h (5 pm-1 pm the next day) daily for 7 days, and cognitive tests were subsequently carried out. The neuromolecular and cellular changes that occurred in the presence and absence of DEX (100 µg kg-1, i.v., at 1 pm and 3 pm every day) were also investigated. RESULTS: CSR mice displayed a decline in learning and memory by 12% (P<0.05) in the Y-maze and by 18% (P<0.01) in the novel object recognition test; these changes were associated with increases in microglial activation, CD68+ microglial phagosome counts, astrocyte-derived complement C3 secretion, and microglial C3a receptor expression (all P<0.05). Synapse elimination, as indicated by a 66% decrease in synaptophysin expression (P=0.0004) and a 45% decrease in postsynaptic density protein-95 expression (P=0.0003), was associated with the occurrence of cognitive deficits. DEX activated astrocytic α2A adrenoceptors and inhibited astrocytic complement C3 release to attenuate synapse elimination through microglial phagocytosis. DEX restored synaptic connections and reversed cognitive deficits induced by CSR. CONCLUSIONS: The results demonstrate that complement pathway activation associated with synapse elimination contributes to sleep loss-related cognitive deficits and that dexmedetomidine protects against sleep deprivation-induced complement activation. Dexmedetomidine holds potential for preventing cognitive deficits associated with sleep loss, which warrants further study.
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Dexmedetomidina , Privação do Sono , Camundongos , Animais , Privação do Sono/complicações , Complemento C3/metabolismo , Complemento C3/farmacologia , Dexmedetomidina/farmacologia , Camundongos Endogâmicos C57BL , Ativação do Complemento , Cognição , Hipocampo/metabolismo , Microglia/metabolismoRESUMO
It has been assumed that patients with strict immunosuppressive treatment after solid organ transplantation have only marginal risk in developing autoimmune encephalitis. We reported a woman in her late 40 s who presented with generalized convulsions and loss of consciousness. After detailed history review, neuropsychological tests, metagenomic next-generation sequencing of serum and cerebrospinal fluid (CSF), magnetic resonance imaging (MRI) brain, and electroencephalogram, she was diagnosed as anti-CASPR2 encephalitis based on the positive anti-CASPR2 auto-antibody in serum and CSF. The patient underwent liver transplantation and has taken lenvatinib for 2 months, in addition to tacrolimus, mycophenotale mofetil, and entecavir administered for half a year. This case was the first report of anti-CASPR2 encephalitis in post-organ transplantation patients. Together with the reports of other encephalitis cases in organ transplantation, it warns the possibility of developing immune-oriented encephalitis in patients undergoing immunosuppression, especially in combination with other treatments of immunomodulatory activity.
Assuntos
Autoanticorpos , Encefalite , Feminino , Humanos , Encefalite/tratamento farmacológico , Encefalite/etiologia , Terapia de Imunossupressão/efeitos adversos , FígadoRESUMO
Genetic hearing loss is a common health problem with no effective therapy currently available. DFNA15, caused by mutations of the transcription factor POU4F3, is one of the most common forms of autosomal dominant non-syndromic deafness. In this study, we established a novel mouse model of the human DFNA15 deafness, with a Pou4f3 gene mutation (Pou4f3Δ) identical to that found in a familial case of DFNA15. The Pou4f3(Δ/+) mice suffered progressive deafness in a similar manner to the DFNA15 patients. Hair cells in the Pou4f3(Δ/+) cochlea displayed significant stereociliary and mitochondrial pathologies, with apparent loss of outer hair cells. Progression of hearing and outer hair cell loss of the Pou4f3(Δ/+) mice was significantly modified by other genetic and environmental factors. Using Pou4f3(-/+) heterozygous knockout mice, we also showed that DFNA15 is likely caused by haploinsufficiency of the Pou4f3 gene. Importantly, inhibition of retinoic acid signaling by the aldehyde dehydrogenase (Aldh) and retinoic acid receptor inhibitors promoted Pou4f3 expression in the cochlear tissue and suppressed the progression of hearing loss in the mutant mice. These data demonstrate Pou4f3 haploinsufficiency as the main underlying cause of human DFNA15 deafness and highlight the therapeutic potential of Aldh inhibitors for treatment of progressive hearing loss.
Assuntos
Aldeído Desidrogenase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Células Ciliadas Auditivas/patologia , Perda Auditiva/tratamento farmacológico , Perda Auditiva/etiologia , Proteínas de Homeodomínio/genética , Fator de Transcrição Brn-3C/genética , Animais , Benzaldeídos/farmacologia , Modelos Animais de Doenças , Haploinsuficiência/genética , Perda Auditiva/genética , Perda Auditiva/patologia , Proteínas de Homeodomínio/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Ruído/efeitos adversos , Quinolinas/farmacologia , Fator de Transcrição Brn-3C/metabolismo , Tretinoína/farmacologia , para-Aminobenzoatos/farmacologiaRESUMO
Renal interstitial fibrosis, a pathological feature of diabetic nephropathy, is closely related to endothelial-to-mesenchymal transition (EMT). This study aimed to explore the effect of H-1-2, a polysaccharide of Pseudostellaria heterophylla, on high glucose (HG) induced-podocyte EMT in vivo and ex vivo. DBA/2 mice were given five consecutive days of streptozotocin injection to induce the diabetic nephropathy model. H-1-2 treatment effectively attenuated general states (bodyweight and blood glucose level) and reduced oral glucose tolerance, insulin tolerance, kidney index, as well as the level of serum urine nitrogen, serum creatinine, and urinary albumin excretion rate in diabetic nephropathy mice. The injury and EMT of podocytes in diabetic nephropathy mice were restrained by H-1-2. After exposing podocytes to HG, the impaired cell viability, apoptosis, the downregulation of nephrin, synaptopodin, sirtuin 1 (SIRT1) and P-cadherin, and the upregulation of N-cadherin were observed in podocytes. H-1-2 treatment could reverse these effects induced by HG. To uncover the mechanism underlying H-1-2 suppressing EMT, small interference RNA for SIRT1 was transfected into podocytes. Mechanically, silencing SIRT1 largely restrained the protective effect of H-1-2 on HG-induced podocytes. In conclusion, H-1-2 exerts a potential role in alleviating HG-induced dysfunction and EMT of podocytes in vivo and ex vivo via SIRT1.