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1.
Cell Commun Signal ; 22(1): 220, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589923

RESUMO

Endosomal single-stranded RNA-sensing Toll-like receptor-7/8 (TLR7/8) plays a pivotal role in inflammation and immune responses and autoimmune diseases. However, the mechanisms underlying the initiation of the TLR7/8-mediated autoimmune signaling remain to be fully elucidated. Here, we demonstrate that miR-574-5p is aberrantly upregulated in tissues of lupus prone mice and in the plasma of lupus patients, with its expression levels correlating with the disease activity. miR-574-5p binds to and activates human hTLR8 or its murine ortholog mTlr7 to elicit a series of MyD88-dependent immune and inflammatory responses. These responses include the overproduction of cytokines and interferons, the activation of STAT1 signaling and B lymphocytes, and the production of autoantigens. In a transgenic mouse model, the induction of miR-574-5p overexpression is associated with increased secretion of antinuclear and anti-dsDNA antibodies, increased IgG and C3 deposit in the kidney, elevated expression of inflammatory genes in the spleen. In lupus-prone mice, lentivirus-mediated silencing of miR-574-5p significantly ameliorates major symptoms associated with lupus and lupus nephritis. Collectively, these results suggest that the miR-574-5p-hTLR8/mTlr7 signaling is an important axis of immune and inflammatory responses, contributing significantly to the development of lupus and lupus nephritis.


Assuntos
Nefrite Lúpica , MicroRNAs , Humanos , Camundongos , Animais , Nefrite Lúpica/genética , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/genética , Receptor 8 Toll-Like/metabolismo , Rim/metabolismo , Camundongos Transgênicos , MicroRNAs/genética
2.
Environ Res ; 242: 117713, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38000633

RESUMO

Urban green waste and food waste are often used as bulking agents to prepare home compost in combination with animal manure in urban horticulture and community gardening. Although it is known that antimicrobial resistance genes (ARGs) persist in home compost, their origins have not been determined. In addition, the factors contributing to ARGs persistence remain unclear. In this study, we aim to (i) characterize the changes in the microbiome and antimicrobial resistome during the composting process of home compost using metagenomics shotgun sequencing, (ii) identify the source of the ARGs persisted in home compost using SourceTracker, and (iii) elucidate the collective effect of compost microbiome and environmental factors, including the physicochemical properties and antibiotics concentration of home compost, in contributing to ARG persistence using Procrustes analysis, co-occurrence network analysis, variation partitioning analysis, and structural equation modeling. SourceTracker analysis indicated that urban green waste bulking agent was the major source of the persisting ARGs in home compost instead of animal manure. Procrustes analysis and co-occurrence network analysis revealed a strong association between microbiome and antimicrobial resistome. Variation partitioning analysis and structural equation modeling suggested that physicochemical properties shaped the antimicrobial resistome directly and indirectly by influencing the microbiome. Our results indicated that the persistence of ARGs in home compost might be due to the succession of microbial species from the urban green waste bulking agent, and the physicochemical properties might have defined the compost environment to shape the microbiome in the compost, thus, in turn, the persisting antimicrobial resistome.


Assuntos
Compostagem , Oxazolidinonas , Eliminação de Resíduos , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Esterco/análise , Alimentos , Genes Bacterianos
3.
Front Oncol ; 13: 1227016, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37675218

RESUMO

Although the role of METTL3 has been extensively studied in many cancers, its role in isoform switching in prostate cancer (PCa) has been poorly explored. To investigate its role, we applied standard RNA-sequencing and long-read direct RNA-sequencing from Oxford Nanopore to examine how METTL3 affects alternative splicing (AS) in two PCa cell lines. By dissecting genome-wide METTL3-regulated AS events, we noted that two PCa cell lines (representing two different PCa subtypes, androgen-sensitive or resistant) behave differently in exon skipping and intron retention events following METTL3 depletion, suggesting AS heterogeneity in PCa. Moreover, we revealed that METTL3-regulated AS is dependent on N6-methyladenosine (m6A) and distinct splicing factors. Analysis of the AS landscape also revealed cell type specific AS signatures for some genes (e.g., MKNK2) involved in key functions in PCa tumorigenesis. Finally, we also validated the clinical relevance of MKNK2 AS events in PCa patients and pointed to the possible regulatory mechanism related to m6A in the exon14a/b region and SRSF1. Overall, we characterize the role of METTL3 in regulating PCa-associated AS programs, expand the role of METTL3 in tumorigenesis, and suggest that MKNK2 AS events may serve as a new potential prognostic biomarker.

4.
Int J Mol Sci ; 24(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37629036

RESUMO

Imbalance of the immune system caused by alterations of the gut microbiome is considered to be a critical factor in the pathogenesis of infant eczema, but the exact role of the gut microbiome in adult atopic dermatitis (AD) patients remains to be clarified. To investigate the differences of the gut microbiome between adult AD patients and healthy individuals, stool samples of 234 adults, containing 104 AD patients and 130 healthy subjects, were collected for 16S rRNA gene amplicon. Altered structure and metabolic dysfunctions of the gut microbiome were identified in adult AD patients. Our results illustrated that the adult AD patients were more likely to have allergies, particularly non-food allergies. In addition, the gut microbiome composition of the AD and normal groups were considerably different. Moreover, Romboutsia and Clostridi-um_sensu_stricto_1 was enriched in the normal group, whereas Blautia, Butyricicoccus, Lachnoclostridium, Eubacterium_hallii_group, Erysi-pelatoclostridium, Megasphaera, Oscillibacter, and Flavonifractor dominated in the AD group. Additionally, purine nucleotide degradation pathways were significantly enriched in the AD group, and the enrichment of proteinogenic amino acid biosynthesis pathways was found in the normal group. This study provides insights into new therapeutic strategies targeting the gut microbiome for AD and evidence for the involvement of the gut-skin axis in AD patients.


Assuntos
Dermatite Atópica , Microbioma Gastrointestinal , Hipersensibilidade , Lactobacillales , Lactente , Humanos , Adulto , Microbioma Gastrointestinal/genética , População do Leste Asiático , RNA Ribossômico 16S/genética , Clostridiaceae
5.
Front Genet ; 14: 1153847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124612

RESUMO

Observational studies revealed altered gut microbial composition in patients with allergic diseases, which illustrated a strong association between the gut microbiome and the risk of allergies. However, whether such associations reflect causality remains to be well-documented. Two-sample mendelian randomization (2SMR) was performed to estimate the potential causal effect between the gut microbiota and the risk of allergic diseases. 3, 12, and 16 SNPs at the species, genus, and family levels respectively of 15 microbiome features were obtained as the genetic instruments of the exposure dataset from a previous study. GWAS summary data of a total of 17 independent studies related to allergic diseases were collected from the IEU GWAS database for the outcome dataset. Significant causal relationships were obtained between gut microbiome features including Ruminococcaceae, Eggerthella, Bifidobacterium, Faecalibacterium, and Bacteroides and the risk of allergic diseases. Furthermore, our results also pointed out a number of putative associations between the gut microbiome and allergic diseases. Taken together, this study was the first study using the approach of 2SMR to elucidate the association between gut microbiome and allergic diseases.

6.
Biomedicines ; 10(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36428472

RESUMO

Atopic dermatitis (AD) has been shown to be closely related to gut dysbiosis mediated through the gut−skin axis, and thus the gut microbiome has recently been explored as a potential therapeutic target for the treatment of AD. Contrasting and varying efficacy have been reported since then. In order to investigate the determining factor of probiotics responsiveness in individuals with AD, we initiated the analysis of 41 AD patients with varying disease severity in Hong Kong, whereas the severity was assessed by Eczema Area and Severity Index (EASI) by board certified dermatologist. 16S rRNA sequencing on the fecal samples from AD patients were performed to obtain the metagenomics profile at baseline and after 8 weeks of oral administration of a novel E3 probiotics formula (including prebiotics, probiotics and postbiotics). While EASI of the participants were significantly lower after the probiotics treatment (p < 0.001, paired Wilcoxon signed rank), subjects with mild AD were found to be more likely to respond to the probiotics treatment. Species richness among responders regardless of disease severity were significantly increased (p < 0.001, paired Wilcoxon signed rank). Responders exhibited (1) elevated relative abundance of Clostridium, Fecalibacterium, Lactobacillus, Romboutsia, and Streptococcus, (2) reduced relative abundance of Collinsella, Bifidobacterium, Fusicatenibacter, and Escherichia-Shigella amid orally-intake probiotics identified using the machine learning algorithm and (3) gut microbiome composition and structure resembling healthy subjects after probiotics treatment. Here, we presented the gut microbiome dynamics in AD patients after the administration of the E3 probiotics formula and delineated the unique gut microbiome signatures in individuals with AD who were responding to the probiotics. These findings could guide the future development of probiotics use for AD management.

7.
Microbiol Spectr ; 10(3): e0012922, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35546575

RESUMO

Despite distinct nasopharyngeal microbiome (NPM) profiles between asthmatics and healthy subjects, little is known about the NPM dynamics and its relation to childhood asthma exacerbation (AE). We investigated NPM changes by longitudinally collecting 135 flocked nasopharyngeal swabs (FNPSs) from 33 school-age asthmatic children at six time points (2 to 4-week intervals) from September to December 2017 in Hong Kong. Subjects were categorized into AE and stable asthma (AS) groups according to whether they experienced any exacerbation during follow-up. One-off FNPSs from nine nonasthmatic children were included as controls. Microbiota profiles were analyzed using 16S rRNA gene sequencing. All 144 NPMs were classified into six microbiome profile groups (MPGs), each dominated by Moraxella, Corynebacterium 1, Dolosigranulum, Staphylococcus, Streptococcus, or Anoxybacillus. The microbial diversity and compositions of NPM in exacerbation samples were different from both baseline samples and those from healthy controls. Moraxella and Dolosigranulum-dominated NPM exhibited high temporal stability revealed by MPG transition analysis. NPM diversity decreased whereas microbial composition remained similar over time. The relative abundances of Moraxella increased while Corynebacterium 1, Anoxybacillus, and Pseudomonas decreased longitudinally. However, these temporal patterns did not differ between AE and AS groups, suggesting that short-term dynamic patterns were not sufficient to predict AE occurrence. Asthmatic NPM underwent Moraxella expansion during AE and presented a high microbiome resilience (recovery potential) after AE resolution. Microbial pathways involved in methane, ketone bodies, and vitamin B3 metabolisms were enhanced during AE and primarily contributed by Moraxella. IMPORTANCE Evidence on the dynamic changes of NPM in asthmatic patients remains limited. Here, we present that asthmatic NPMs deviating from a healthy status still showed resilience after disturbance. Our data imply from a longitudinal perspective that Moraxella increase is closely related to AE occurrence. The finding of functional dysbiosis (imbalance) during AE offers a plausible explanation for the known association between nasopharyngeal Moraxella expansion and increased AE risk. This work serves as a basis for future long-term prospective studies leveraging multiomics approaches to elucidate the temporal association between NPM and pediatric AE.


Assuntos
Asma , Microbiota , Criança , Corynebacterium/genética , Humanos , Microbiota/genética , Moraxella/genética , Nasofaringe/microbiologia , Estudos Prospectivos , RNA Ribossômico 16S/genética
8.
Mol Biol Evol ; 39(5)2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35535514

RESUMO

Highly diversified astigmatic mites comprise many medically important human household pests such as house dust mites causing ∼1-2% of all allergic diseases globally; however, their evolutionary origin and diverse lifestyles including reversible parasitism have not been illustrated at the genomic level, which hampers allergy prevention and our exploration of these household pests. Using six high-quality assembled and annotated genomes, this study not only refuted the monophyly of mites and ticks, but also thoroughly explored the divergence of Acariformes and the diversification of astigmatic mites. In monophyletic Acariformes, Prostigmata known as notorious plant pests first evolved, and then rapidly evolving Astigmata diverged from soil oribatid mites. Within astigmatic mites, a wide range of gene families rapidly expanded via tandem gene duplications, including ionotropic glutamate receptors, triacylglycerol lipases, serine proteases and UDP glucuronosyltransferases. Gene diversification after tandem duplications provides many genetic resources for adaptation to sensing environmental signals, digestion, and detoxification in rapidly changing household environments. Many gene decay events only occurred in the skin-burrowing parasitic mite Sarcoptes scabiei. Throughout the evolution of Acariformes, massive horizontal gene transfer events occurred in gene families such as UDP glucuronosyltransferases and several important fungal cell wall lytic enzymes, which enable detoxification and digestive functions and provide perfect drug targets for pest control. This comparative study sheds light on the divergent evolution and quick adaptation to human household environments of astigmatic mites and provides insights into the genetic adaptations and even control of human household pests.


Assuntos
Adaptação Fisiológica , Genômica , Adaptação Fisiológica/genética , Genoma , Humanos , Difosfato de Uridina
9.
Cancers (Basel) ; 13(23)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34885177

RESUMO

Early diagnosis and treatment do not prevent the high morbidity and poor prognosis of oral tongue squamous cell carcinoma (TSCC). Earlier studies have shown that ARG1 signaling is deregulated in TSCC. Here, we investigated the complexity of ARG1 metabolism in this cancer subsite to appreciate the therapeutic potential of this potential biological vulnerability. Various functional studies show that ARG1 overexpression in oral cancer cells inhibits cell proliferation and invasion compared with controls. Further, RNA-sequencing revealed numerous differentially expressed genes (DEGs) and associated networks were dysregulated by ARG1 overexpression, including hypoxia-inducible factor (HIFα) signaling, the natural killer cell signaling pathway and interferon signaling. Our work provides a foundation for understanding the mechanism of action of disrupted arginine metabolism in oral tongue squamous cell carcinoma. This may impact the community for developing further therapeutic approaches.

10.
Front Microbiol ; 12: 792556, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35250904

RESUMO

Microbiome mediates early life immune deviation in asthma development. Recurrent wheeze (RW) in pre-school years is a risk factor for asthma diagnosis in school-age children. Dysbiosis exists in asthmatic airways, while its origin in pre-school years and relationship to RW is not clearly defined. This study investigated metagenomics of nasopharyngeal microbiome in pre-school children with RW. We applied whole-genome shotgun sequencing and human rhinovirus (HRV) detection on nasopharyngeal samples collected from three groups of pre-school children: (i) RW group: 16 children at-risk for asthma who were hospitalized for RW, (ii) inpatient control (IC): 18 subjects admitted for upper respiratory infection, and (iii) community control (CC): 36 children without respiratory syndromes. Sequence reads were analyzed by MetaPhlAn2 and HUMAnN2 algorithm for taxonomic and functional identification. Linear discriminant analysis effect size (LEfSe) analysis was used to identify discriminative features. We identified that Moraxella catarrhalis and Dolosigranulum pigrum were predominant species in nasopharynx. RW had lower alpha diversity (Shannon diversity index) than CC (0.48 vs. 1.07; P adj = 0.039), characterized by predominant Proteobacteria. LEfSe analysis revealed D. pigrum was the only discriminative species across groups (LDA = 5.57, P = 0.002), with its relative abundance in RW, IC, and CC being 9.6, 14.2, and 37.3%, respectively (P < 0.05). LEfSe identified five (ribo)nucleotides biosynthesis pathways to be group discriminating. Adjusting for HRV status, pre-school children with RW have lower nasopharyngeal biodiversity, which is associated with Proteobacteria predominance and lower abundance of D. pigrum. Along with discriminative pathways found in RW and CC, these microbial biomarkers help to understand RW pathogenesis.

11.
Microb Pathog ; 145: 104231, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32344179

RESUMO

Mycoplasma genitalium is one of the sexually transmitted pathogens that cause significant morbidity in the host. The development of effective therapeutic procedures is urgently needed to counter the multi-drug resistant events imposed by this pathogen. In the current version of M. genitalium G37 genome, 512 open reading frames have been identified. The function of 91 proteins encoded by M. genitalium genes was found to be hypothetical and these proteins were termed hypothetical proteins (HPs). This study aims to carry out functional characterization of HPs by a systems biology approach. Functional assignments of 61 HPs were made with high confidence. They belong to different functional groups, such as DNA-binding proteins, helicases and transporters. Approximately 26% of HPs were identified as transporters, suggesting that M. genitalium is likely to rely on the exogenous nutrient supply for survival. A group of 20 proteins was predicted to be virulence factors, indicating the pathogenic characteristics of M. genitalium. Among the coding proteins, six proteins were pathogen-specific and could serve as potential drug targets by subtractive proteomics analysis. Network analysis of the HPs suggested that several critical proteins were involved in SOS response and stringent response in M. genitalium. These findings provided a better picture of M. genitalium genome and novel clues for studying the potential infection mechanism in this bacterium.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Preparações Farmacêuticas , Humanos , Mycoplasma genitalium/genética , Fases de Leitura Aberta , Proteômica , Biologia de Sistemas
12.
Pediatr Allergy Immunol ; 30(6): 624-631, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31132163

RESUMO

BACKGROUND: Allergic rhinoconjunctivitis (ARC) is a prevalent allergic condition in the pediatric population. Microbial dysbiosis has increasingly been recognized to influence on host immunity and allergic diseases. However, the microbial profile of ARC has not been characterized. This cross-sectional study aims to evaluate the changes in nasal and ocular surface microbiome of children with ARC. METHODS: Ocular and nasopharyngeal swabs were collected from controls and pediatric ARC cases for 16S rRNA amplicon sequencing. The bacterial community profile was analyzed. The correlation of the microbial diversity with the ARC-related clinical scores was studied. RESULTS: A total of 23 patients with ARC and 17 healthy controls were recruited;30 were ocular samples (15 controls vs 15 ARC), while 40 were nasal samples (17controls vs 23 ARC) The alpha diversity of nasopharyngeal microbiome was significantly higher in ARC patients than healthy controls (P < 0.01), but not for ocular microbiome. The clinical scores in all subjects were negatively correlated with the Shannon diversity for ocular (P = 0.014) and positively correlated with nasopharyngeal (P = 0.010) microbiome. While the ocular microbiome remained significantly distinct from nasopharyngeal microbiome in terms of both alpha and beta diversity in both healthy subjects and ARC patients, significant differences of relative abundance of certain phyla (Bacteroidetes, Cyanobacteria, and Deinococcus-Thermus) and genera (Dolosigranulum and Moraxella) between nasal and ocular surfaces were only detected in healthy controls, but not in the ARC subjects, suggesting the microbial composition at both body sites becoming more similar at disease state. CONCLUSION: This study reported (a) a higher alpha diversity in ocular than nasopharyngeal microbiome in both ARC patients and controls, and (b) nasopharyngeal microbiome became more diverse in ARC patients than in controls. Our results suggested an interaction of the microbiome between ocular and nasal compartments in patients with ARC.


Assuntos
Conjuntivite Alérgica/microbiologia , Disbiose/imunologia , Olho/microbiologia , Microbiota/genética , Nasofaringe/microbiologia , RNA Ribossômico 16S/genética , Rinite Alérgica/microbiologia , Adolescente , Criança , Estudos Transversais , Olho/imunologia , Fezes/microbiologia , Feminino , Interações entre Hospedeiro e Microrganismos , Humanos , Masculino , Nasofaringe/imunologia
13.
Front Genet ; 7: 193, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27857721

RESUMO

Lung cancer is the most common cause of cancer deaths all over the world, in which non-small cell lung cancer (NSCLC) accounts for ~85% of cases. It is well known that microRNAs (miRNAs) play a critical role in various cellular processes, mediating post-transcriptional silencing either by mRNA degradation through binding the 3' UTR of target mRNA or by translational inhibition of the protein. In the past decade, miRNAs have also been increasingly identified in biological fluids such as human serum or plasma known as circulating or cell-free miRNAs, and may function as non-invasive diagnostic markers for various cancer types including NSCLC. Circulating tumor cells (CTCs) are those cells that are shed from solid tumors and then migrate into the circulation. However, reports concerning the roles of CTCs are quite rare, which may be attributed to the difficulties in the enrichment and detection of CTCs in the circulation. Although, there have been reassuring advances in identifying circulating miRNA-panels, which are assumed to be of diagnostic value in NSCLC early stage, some issues remain concerning the reliability of using miRNA panels as a diagnostic tool for NSCLC. In the current review, we are aiming at providing insights into the miRNAs biology, the mechanisms of miRNAs release into the bloodstream, cell-free miRNAs as the diagnostic markers for NSCLC and the current limitations of CTCs as diagnostic markers in NSCLC.

14.
Biochim Biophys Acta ; 1839(2): 97-106, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24389345

RESUMO

Sfmbt2-hosted miR-466a-3p and its close relatives are often among the most significantly up-regulated or down-regulated miRNAs in responses to numerous deleterious environmental stimuli. The exact roles of these miRNAs in cellular stress responses, however, are not clear. Here we showed that many Sfmbt2-hosted miRNAs were highly hypertonic stress responsive in vitro and in vivo. In renal medulla, water deprivation induced alterations in the expression of miR-466(a/b/c/e/p)-3p in a pattern similar to that of miR-200b-3p, a known regulator of osmoresponsive transcription factor Nfat5. Remarkably, exposure of mIMCD3 cells to an arginine vasopressin analog time-dependently down-regulated the expression of miR-466(a/b/c/e/p)-3p and miR-200b-3p, which provides a novel regulatory mechanism for these osmoresponsive miRNAs. In cultured mIMCD3 cells we further demonstrated that miR-466a-3p and miR-466g were capable of targeting Nfat5 by interacting with its 3'UTR. In transgenic mice overexpressing miR-466a-3p, significant down-regulation of Nfat5 and many other osmoregulation-related genes was observed in both the renal cortex and medulla. Moreover, sustained transgenic over-expression of miR-466a-3p was found to be associated with polydipsia, polyuria and disturbed ion homeostasis and kidney morphology. Since the mature sequence of miR-466a-3p is completely equivalent to that of miR-466e-3p and that the seed sequence of miR-466a-3p is completely equivalent to that of miR-297(a/b/c)-3p, miR-466d-3p, miR-467g and miR-669d-3p, and that miR-466a-3p differs from miR-466(b/c/p)-3p only in a 5' nucleotide, we propose that miR-466a-3p and many of its close relatives are important epigenetic regulators of renal Nfat5 signaling, osmoregulation and urine concentration in mice.


Assuntos
Íntrons/genética , Capacidade de Concentração Renal/genética , MicroRNAs/genética , Fatores de Transcrição NFATC/genética , Osmorregulação/genética , Fatores de Transcrição/genética , Regiões 3' não Traduzidas/genética , Animais , Arginina Vasopressina/análogos & derivados , Arginina Vasopressina/farmacologia , Sequência de Bases , Western Blotting , Linhagem Celular , Creatina/sangue , Creatina/urina , Epigênese Genética , Expressão Gênica/efeitos dos fármacos , Córtex Renal/metabolismo , Medula Renal/metabolismo , Camundongos , Camundongos Transgênicos , Fatores de Transcrição NFATC/metabolismo , Potássio/sangue , Potássio/urina , Proteínas Repressoras , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Transdução de Sinais/genética , Sódio/sangue , Sódio/urina , Ureia/sangue , Ureia/urina
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