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1.
Food Funct ; 14(8): 3880-3892, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37038883

RESUMO

Previous evidence has indicated that fatigue and a high-fat diet (HFD) cause the adaptive organism responses to be dysregulated, resulting in gastrointestinal (GI) disorders. Generally, gut microbiota plays a crucial role in GI disorders. However, the impact of fatigue and an HFD on the microbiome and GI disorders remains to be fully explored. Mice were randomly divided into the control group (CCN), standing group (CSD), lard group (CLD), and standing + lard group (CSLD). Mice in the CSD and CSLD groups stood on the multiple-platform apparatus for four h per day for 14 consecutive days. From the eighth day, mice in the CLD and CSLD groups were fed intragastric lard and the CCN and CSD groups were subjected to intragastric treatment with sterile water, 0.4 mL per each, twice a day for seven days. Subsequently, we analyzed the characteristics and interaction relationship of gut content microbiota (GCM), brain-gut peptides, and lipid metabolism. Mice in the CSLD group were in a fatigued state and had diarrhea. Compared with the CCN group, high-density lipoproteins were significantly lower, and the lipid droplet optical density value was substantially higher in the CSLD group (p < 0.05). CSLD mice presented significant structural damage to the small intestine and considerably higher ß-endorphin, cholecystokinin, and somatostatin (p < 0.05). Bacillus, Gemella, and Bosea were the characteristic bacteria of the CSLD group, and Gemella was significantly negatively correlated with total cholesterol. Gut microbiota dysbiosis and dysregulated lipid metabolism contribute to diarrhea caused by an HFD diet in a fatigued state.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Metabolismo dos Lipídeos , Microbioma Gastrointestinal/fisiologia , Disbiose/microbiologia , Diarreia , Camundongos Endogâmicos C57BL
2.
Chin J Integr Med ; 29(6): 556-565, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37052766

RESUMO

Postoperative adhesion (PA) is currently one of the most unpleasant complications following surgical procedures. Researchers have developed several new strategies to alleviate the formation of PA to a great extent, but so far, no single measure or treatment can meet the expectations and requirements of clinical patients needing complete PA prevention. Chinese medicine (CM) has been widely used for thousands of years based on its remarkable efficacy and indispensable advantages CM treatments are gradually being accepted by modern medicine. Therefore, this review summarizes the formating process of PA and the efficacy and action mechanism of CM treatments, including their pharmacological effects, therapeutic mechanisms and advantages in PA prevention. We aim to improve the understanding of clinicians and researchers on CM prevention in the development of PA and promote the in-depth development and industrialization process of related drugs.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Aderências Teciduais/tratamento farmacológico , Aderências Teciduais/prevenção & controle , Desenvolvimento Industrial , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
3.
Diabetes Metab Syndr Obes ; 15: 2563-2581, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035516

RESUMO

Purpose: Type 2 diabetes mellitus (T2DM) is a complex genetic disease associated with genetic and environmental factors. Previous studies have shown that changes in the gut microbiota may affect the development of host metabolic diseases and promote the progression of T2DM. Tang-ping-san (TPS) decoction can effectively treat T2DM. However, its specific mechanisms must be evaluated. Patients and Methods: In the present study, we established an animal model of T2DM using a high­fat diet (HFD) with intraperitoneal injection streptozotocin injection. Results: The therapeutic effect of TPS decoction on T2DM in mice was initially evaluated. TPS decoction was found to improve hyperglycemia, hyperlipidemia, insulin resistance, and pathological liver, pancreatic, and colon changes. Moreover, it reduced the pro-inflammatory cytokine levels. Based on 16SrRNA sequencing, TPS decoction reduced the Firmicutes/Bacteroidetes ratio at the phylum level. At the genus level, it increased the relative abundances of Akkermansia, Muribaculaceae, and the Eubacterium coprostanoligenes group and decreased the relative abundance of Fusobacterium, Escherichia coli, Dubosiella, and Helicobacter. Conclusion: TPS decoction improves T2DM and liver function and reduces the risk of hyperglycemia, hyperlipidemia, insulin resistance, pathological organ changes, and inflammatory reactions. The mechanism of TPS decoction in T2DM can be correlated with the reversal of gut microbiota dysfunction and repair of the intestinal mucosal barrier.

4.
Front Plant Sci ; 13: 887133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651770

RESUMO

Polyploidy, or whole-genome duplication (WGD), often induces dramatic changes in gene expression due to "transcriptome shock. " However, questions remain about how allopolyploidy (the merging of multiple nuclear genomes in the same nucleus) affects gene expression within and across multiple tissues and developmental stages during the initial foundation of allopolyploid plants. Here, we systematically investigated the immediate effect of allopolyploidy on gene expression variation in an artificial allopolyploidy system consisting of a constructed allotetraploid wheat (AADD genome, accession AT2) and its diploid progenitors Triticum urartu and Aegilops tauschii. We performed comprehensive RNA sequencing of 81 samples from different genotypes, tissues, and developmental stages. First, we found that intrinsic interspecific differences between the diploid parents played a major role in establishing the expression architecture of the allopolyploid. Nonetheless, allopolyploidy per se also induced dramatic and asymmetric patterns of differential gene expression between the subgenomes, and genes from the D subgenome exhibited a more drastic response. Second, analysis of homoeolog expression bias (HEB) revealed that the D subgenome exhibited significant expression bias and that de novo-generated HEB was attributed mainly to asymmetrical differential gene expression. Homoeolog-specific expression (HSE) analyses showed that the cis-only regulatory pattern was predominant in AT2, reflecting significant divergence between the parents. Co-expression network analysis revealed that homoeolog expression connectivity (HEC) was significantly correlated with sequence divergence in cis elements between subgenomes. Interestingly, allopolyploidy-induced reconstruction of network modules was also associated with different HSE patterns. Finally, a transcriptome atlas of spike development demonstrated that the phenotypic similarity of AT2 to T. urartu may be attributed to the combination of relatively stable expression of A-subgenome genes and drastic downregulation of their D-subgenome homoeologs. These findings provide a broad, multidimensional characterization of allopolyploidy-induced transcriptomic responses and suggest that allopolyploidy can have immediate and complex regulatory effects on the expression of nuclear genes.

5.
Biomed Pharmacother ; 154: 113603, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36942596

RESUMO

Pulmonary fibrosis is an abnormal wound-healing response to repeated alveolar injury, characterized by continuous inflammation and abnormal collagen deposition. Its treatment is problematic. Astragaloside (AST) is an active component of Astragalus membranaceus with anti-inflammatory and anti-tumor properties. Although the underlying mechanisms are unknown, AST is also used to treat fibrotic diseases. This study aimed to investigate the mechanisms of action of AST in pulmonary fibrosis treatment. We found that AST significantly improved restrictive ventilatory impairment, compliance, total lung capacity, and functional residual capacity. In mice with pulmonary fibrosis, extracellular matrix deposition in the pulmonary parenchyma and intemperate inflammation were reversed. This therapeutic effect can be attributed to autophagy, activating the genes for autophagy flux and autophagic vacuoles. Impaired autophagy increased susceptibility to pulmonary fibrosis by exacerbating collagen deposition in vitro and in vivo. Using a combination of molecular docking and network pharmacology, the Ras/Raf/MEK/ERK signaling pathway was identified as a possible candidate for the pharmacologic target of AST. Functional dephosphorylation of MEK and ERK inhibited the Ras/Raf/MEK/ERK signaling pathway, which converges at the rapamycin switch to initiate autophagy. Inhibitors of Ras and MEK regulated autophagy. These findings suggest that AST might treat pulmonary fibrosis by modulating the Ras/Raf/MEK/ERK signaling pathway mediated by depression.


Assuntos
Fibrose Pulmonar , Camundongos , Animais , Fibrose Pulmonar/tratamento farmacológico , Simulação de Acoplamento Molecular , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Autofagia , Inflamação , Colágeno/metabolismo
6.
Int J Pharm ; 592: 119936, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33038455

RESUMO

Ethosomes are widely applied as the carriers for the transdermal delivery of hydrophobic and hydrophilic drugs. Herein, curcumin-loaded ethosomes (CE) with different phospholipid composition were formulated and thoroughly compared. A significant interaction between the unsaturated phosphatidylcholine (PC) and saturated hydrogenated phosphatidylcholine (HPC) was found by molecular simulation and differential scanning calorimetry (DSC), which led to the reduction of PC peroxidation with the presence of HPC. Subsequently, the composite phospholipid ethosomes containing curcumin were prepared for the first time to evaluate their properties in comparison with the conventional ethosomes composed of PC (CE-P) or HPC (CE-H). CE with PC/HPC ratio of 1:1 (CE-P1H1) with the best vesicle stability and flexibility significantly decreased the uptake by HaCaT cells compared to CE-H and free curcumin, indicating reduced skin cell toxicity. Compared with free curcumin, CE-P1H1 had the highest transdermal efficiency (p < 0.001), followed by CE-P (p < 0.05), partly due to the fact that CE-P1H1 could disturb lipid domain of stratum corneum (SC). Moreover, CE-P1H1 was found to promote curcumin for deep penetration of the skin via the hair follicles route. Our study has shown that using composite phospholipid ethosomes as lipid vesicular carriers could enhance transdermal penetration of drugs and increase in the vesicle stability.


Assuntos
Curcumina , Absorção Cutânea , Administração Cutânea , Curcumina/metabolismo , Portadores de Fármacos/metabolismo , Lipossomos/metabolismo , Permeabilidade , Fosfolipídeos/metabolismo , Pele/metabolismo
7.
Proc Natl Acad Sci U S A ; 117(25): 14561-14571, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32518116

RESUMO

Recombination between homeologous chromosomes, also known as homeologous exchange (HE), plays a significant role in shaping genome structure and gene expression in interspecific hybrids and allopolyploids of several plant species. However, the molecular mechanisms that govern HEs are not well understood. Here, we studied HE events in the progeny of a nascent allotetraploid (genome AADD) derived from two diploid progenitors of hexaploid bread wheat using cytological and whole-genome sequence analyses. In total, 37 HEs were identified and HE junctions were mapped precisely. HEs exhibit typical patterns of homologous recombination hotspots, being biased toward low-copy, subtelomeric regions of chromosome arms and showing association with known recombination hotspot motifs. But, strikingly, while homologous recombination preferentially takes place upstream and downstream of coding regions, HEs are highly enriched within gene bodies, giving rise to novel recombinant transcripts, which in turn are predicted to generate new protein fusion variants. To test whether this is a widespread phenomenon, a dataset of high-resolution HE junctions was analyzed for allopolyploid Brassica, rice, Arabidopsis suecica, banana, and peanut. Intragenic recombination and formation of chimeric genes was detected in HEs of all species and was prominent in most of them. HE thus provides a mechanism for evolutionary novelty in transcript and protein sequences in nascent allopolyploids.


Assuntos
Cromossomos de Plantas/genética , Genes de Plantas/genética , Proteínas de Plantas/genética , Poliploidia , Recombinação Genética , Arabidopsis/genética , Arachis/genética , Brassica/genética , Biologia Computacional , Evolução Molecular , Fusão Gênica , Cariotipagem , Musa/genética , Oryza/genética , Transcrição Gênica , Triticum/genética
8.
World J Gastrointest Oncol ; 12(1): 54-65, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31966913

RESUMO

BACKGROUND: Postoperative peritoneal adhesion (PPA), characterized by abdominal pain, female infertility, and even bowel obstruction after surgery, has always been a major concern. The occurrence and formation of adhesion are from complex biological processes. However, the molecular mechanisms underlying the basis of microarray data profile, followed by peritoneal adhesion formation, are largely unknown. AIM: To reveal the underlying pathogenesis of PPA at the molecular level. METHODS: The gene expression profile was retrieved from the Gene Expression Omnibus database for our analysis. We identified a panel of key genes and related pathways involved in adhesion formation using bioinformatics analysis methods. We performed quantitative PCR and western blotting in vivo to validate the results preliminarily. RESULTS: In total, 446 expressed genes were altered in peritoneal adhesion. We found that several hub genes (e.g., tumor necrosis factor, interleukin 1 beta, interleukin 6, C-X-C motif chemokine ligand 1, C-X-C motif chemokine ligand 2) were marked as significant biomarkers. Functional analysis suggested that these genes were enriched in the Toll-like receptor signaling pathway. According to the Kyoto Encyclopedia of Genes and Genomes pathway and published studies, TLR4, myeloid differentiation primary response protein 88 (MyD88), and nuclear factor kappa B (NF-κB) played essential roles in Toll-like signaling transduction. Here, we obtained a regulatory evidence chain of TLR4/MyD88/NF-κB/inflammatory cytokines/peritoneal adhesion involved in the pathogenesis of postoperative adhesion. The results of the microarray analysis were verified by the animal experiments. These findings may extend our understanding of the molecular mechanisms of PPA. CONCLUSION: The regulatory evidence chain of TLR4/MyD88/NF-κB/inflammatory cytokines/peritoneal adhesion may play key roles in the pathogenesis of PPA. Future studies are required to validate our findings.

9.
World J Psychiatry ; 10(12): 286-298, 2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33392005

RESUMO

BACKGROUND: Post-traumatic stress disorder (PTSD) is a serious stress-related disorder. AIM: To identify the key genes and pathways to uncover the potential mechanisms of PTSD using bioinformatics methods. METHODS: Gene expression profiles were obtained from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) were identified by using GEO2R. Gene functional annotation and pathway enrichment were then conducted. The gene-pathway network was constructed with Cytoscape software. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis was applied for validation, and text mining by Coremine Medical was used to confirm the connections among genes and pathways. RESULTS: We identified 973 DEGs including 358 upregulated genes and 615 downregulated genes in PTSD. A group of centrality hub genes and significantly enriched pathways (MAPK, Ras, and ErbB signaling pathways) were identified by using gene functional assignment and enrichment analyses. Six genes (KRAS, EGFR, NFKB1, FGF12, PRKCA, and RAF1) were selected to validate using qRT-PCR. The results of text mining further confirmed the correlation among hub genes and the enriched pathways. It indicated that these altered genes displayed functional roles in PTSD via these pathways, which might serve as key signatures in the pathogenesis of PTSD. CONCLUSION: The current study identified a panel of candidate genes and important pathways, which might help us deepen our understanding of the underlying mechanism of PTSD at the molecular level. However, further studies are warranted to discover the critical regulatory mechanism of these genes via relevant pathways in PTSD.

10.
Mediators Inflamm ; 2019: 1769374, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772499

RESUMO

Intraperitoneal adhesion is a common complication after abdominal surgery, which seriously affects the quality of life of patients. HuoXueTongFu Formula (HXTF) plays an important role in the prevention and treatment of intraperitoneal adhesions. However, the molecular-related mechanisms are still not fully known. In this study, the model of Intrapetitoneal adhesion was established by cecum abrasion and treated with HXTF for one week. RAW264.7 cells were given LPS, IFN-γ, IL-4, HXTF-medicated serum, and PPAR-γ agonist/antagonist, respectively. Histopathology, flow cytometry, ELISA, real-time PCR, and Western blotting were used to further detect the related protein, M1/M2 polarization tendency, and PPAR-γ nuclear translocation. The deposition of collagen fibres reduced in the local area of rats after the operation with HXTF treatment. Similar to IL-4, HXTF induced a tendency for macrophages to polarize toward M2 and promoted peroxisome proliferator-activated receptor-gamma (PPAR-γ) nuclear translocation. Furthermore, the use of HXTF and PPAR-γ agonists downregulated macrophage M1 polarization-related factors IL-1, IL-6, and TNF-alpha and upregulated M2 polarization-related factors IL-4, IL-10, and TGF-beta 1. Meanwhile, the use of HXTF and PPAR-γ agonists downregulated the SOCS3/JAK2/STAT1 pathway and activated the SOCS1/STAT6/PPAR-γ pathway. These results show that HXTF may reduce intraperitoneal adhesion by inducing macrophage M2 polarization and regulating the SOCS/JAK2/STAT/PPAR-γ pathway.


Assuntos
Janus Quinase 2/metabolismo , Macrófagos/metabolismo , PPAR gama/metabolismo , Extratos Vegetais/farmacologia , Fator de Transcrição STAT1/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Animais , Western Blotting , Polaridade Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citometria de Fluxo , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Qualidade de Vida , Células RAW 264.7 , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos
11.
Opt Lett ; 44(19): 4706-4709, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568422

RESUMO

We report successful room-temperature up-conversion random lasing by distributing CsPbBr3 quantum dots (QDs) uniformly into TiO2 nanotubes (NTs). In order to overcome the difficulty in purifying the QDs, TiO2 NTs were designed to collect QDs and enhance the optical multiple scattering effect. A threshold of 9.54 mJ/cm2 and narrow full width at half-maximum of 0.49 nm with a relatively high quality factor of 1089 were successfully observed. These results indicate that CsPbBr3QDs/TiO2 NTs can be high-performance up-conversion lasers for practical applications, especially when the phase matching required by conventional approaches cannot be fulfilled.

12.
World J Gastrointest Oncol ; 11(2): 161-171, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30788042

RESUMO

BACKGROUND: There are several surgical options for treating early gastric cancers (EGCs), such as endoscopic resection, laparoscopic or open gastrectomy with D1 or D2 lymphadenectomy. Endoscopic resection for EGC with low risk of lymph node metastasis has been widely accepted as a therapeutic alternative. The role of endoscopic submucosal dissection (ESD) in treating EGC is not well established, especially when compared with resection surgery cases in a long-term follow-up scope. AIM: To compare the safety and efficacy of the short- and long-term outcomes between ESD and resection surgery. METHODS: We searched the databases of PubMed, EMBASE, Web of Science, and the Cochrane Library from January 1990 to June 2018, enrolling studies reporting short- or long-term outcomes of ESD in comparison with resection surgery for EGC. The quality of the studies was assessed by the Newcastle-Ottawa Quality Assessment Scale. Stata software (version 12.0) was used for the analysis. Pooling analysis was conducted using either fixed- or random-effects models depending on heterogeneity across studies. RESULTS: Fourteen studies comprising 5112 patients were eligible for analysis (2402 for EGC and 2710 for radical surgery). Our meta-analysis demonstrated that the ESD approach showed advantages through decreased operation time [weighted mean difference (WMD): -140.02 min, 95%CI: -254.23 to -34.82 min, P = 0.009], shorter hospital stay (WMD: -5.41 d, 95% CI: -5.93 to -4.89 d, P < 0.001), and lower postoperative complication rate [Odds ratio (OR) = 0.39, 95%CI: 0.28-0.55, P < 0.001). Meanwhile, EGC patients who underwent ESD had higher recurrence rate (OR = 9.24, 95%CI: 5.94-14.36, P < 0.001) than resection surgery patients. However, the long-term survival including overall survival [Hazard ratio (HR) = 0.51, 95%CI: 0.26-1.00, P = 0.05] and event-free survival (HR = 1.59, 95%CI: 0.66-9.81, P = 0.300) showed no significant differences between these two groups. CONCLUSION: In the treatment of EGC, ESD was safe and feasible in comparison with resection surgery, with advantages in several surgical and post-operative recovery parameters. Although the recurrence rate was higher in ESD group, the long-term survival was still comparable in these two groups, suggesting ESD could be recommended as standard treatment for EGC with indications.

13.
New Phytol ; 220(1): 262-277, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29916206

RESUMO

Polyploidy is a prominent route to speciation in plants; however, this entails resolving the challenges of meiotic instability facing abrupt doubling of chromosome complement. This issue remains poorly understood. We subjected progenies of a synthetic hexaploid wheat, analogous to natural common wheat, but exhibiting extensive meiotic chromosome instability, to heat or salt stress. We selected stress-tolerant cohorts and generated their progenies under normal condition. We conducted fluorescent in situ hybridization/genomic in situ hybridization-based meiotic/mitotic analysis, RNA-Seq and virus-induced gene silencing (VIGS)-mediated assay of meiosis candidate genes. We show that heritability of stress tolerance concurred with increased euploidy frequency due to enhanced meiosis stability. We identified a set of candidate meiosis genes with altered expression in the stress-tolerant plants vs control, but the expression was similar to that of common wheat (cv Chinese Spring, CS). We demonstrate VIGS-mediated downregulation of individual candidate meiosis genes in CS is sufficient to confer an unstable meiosis phenotype mimicking the synthetic wheat. Our results suggest that heritable regulatory changes of preexisting meiosis genes may be hitchhiked as a spandrel of stress tolerance, which significantly improves meiosis stability in the synthetic wheat. Our findings implicate a plausible scenario that the meiosis machinery in hexaploid wheat may have already started to evolve at its onset stage.


Assuntos
Instabilidade Cromossômica/genética , Meiose/genética , Poliploidia , Estresse Fisiológico/genética , Triticum/genética , Triticum/fisiologia , Cromossomos de Plantas/genética , Regulação para Baixo/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Temperatura Alta , Padrões de Herança/genética , Cariótipo , Anotação de Sequência Molecular , Fenótipo , Tolerância ao Sal/genética
14.
Plant J ; 94(6): 1141-1156, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29660196

RESUMO

The non-random spatial packing of chromosomes in the nucleus plays a critical role in orchestrating gene expression and genome function. Here, we present a Hi-C analysis of the chromatin interaction patterns in rice (Oryza sativa L.) at hierarchical architectural levels. We confirm that rice chromosomes occupy their own territories with certain preferential inter-chromosomal associations. Moderate compartment delimitation and extensive TADs (Topologically Associated Domains) were determined to be associated with heterogeneous genomic compositions and epigenetic marks in the rice genome. We found subtle features including chromatin loops, gene loops, and off-/near-diagonal intensive interaction regions. Gene chromatin loops associated with H3K27me3 could be positively involved in gene expression. In addition to insulated enhancing effects for neighbor gene expression, the identified rice gene loops could bi-directionally (+/-) affect the expression of looped genes themselves. Finally, web-interleaved off-diagonal IHIs/KEEs (Interactive Heterochromatic Islands or KNOT ENGAGED ELEMENTs) could trap transposable elements (TEs) via the enrichment of silencing epigenetic marks. In parallel, the near-diagonal FIREs (Frequently Interacting Regions) could positively affect the expression of involved genes. Our results suggest that the chromatin packing pattern in rice is generally similar to that in Arabidopsis thaliana but with clear differences at specific structural levels. We conclude that genomic composition, epigenetic modification, and transcriptional activity could act in combination to shape global and local chromatin packing in rice. Our results confirm recent observations in rice and A. thaliana but also provide additional insights into the patterns and features of chromatin organization in higher plants.


Assuntos
Montagem e Desmontagem da Cromatina/genética , Cromatina/genética , Cromossomos de Plantas/genética , Oryza/genética , Cromatina/metabolismo , Cromossomos de Plantas/fisiologia , Epigênese Genética/genética , Marcadores Genéticos/genética , Estudo de Associação Genômica Ampla
15.
Mol Biol Evol ; 35(5): 1078-1091, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29365173

RESUMO

Although a distinct karyotype with defined chromosome number and structure characterizes each biological species, it is intrinsically labile. Polyploidy or whole-genome duplication has played a pervasive and ongoing role in the evolution of all eukaryotes, and is the most dramatic force known to cause rapid karyotypic reconfiguration, especially at the initial stage. However, issues concerning transgenerational propagation of karyotypic heterogeneity and its translation to phenotypic diversity in nascent allopolyploidy, at the population level, have yet to be studied in detail. Here, we report a large-scale examination of transgenerationally propagated karyotypic heterogeneity and its phenotypic manifestation in an artificially constructed allotetraploid with a genome composition of AADD, that is, involving two of the three progenitor genomes of polyploid wheat. Specifically, we show that 1) massive organismal karyotypic heterogeneity is precipitated after 12 consecutive generations of selfing from a single euploid founder individual, 2) there exist dramatic differences in aptitudes between subgenomes and among chromosomes for whole-chromosome gain and/or loss and structural variations, 3) majority of the numerical and structural chromosomal variations are concurrent due to mutual contingency and possible functional constraint, 4) purposed and continuous selection and propagation for euploidy over generations did not result in enhanced karyotype stabilization, and 5) extent of karyotypic variation correlates with variability of phenotypic manifestation. Together, our results document that allopolyploidization catalyzes rampant and transgenerationally heritable organismal karyotypic heterogeneity that drives population-level phenotypic diversification, which lends fresh empirical support to the still contentious notion that whole-genome duplication enhances organismal evolvability.


Assuntos
Evolução Biológica , Instabilidade Cromossômica , Cariótipo , Poliploidia , Triticum/genética , Cromossomos de Plantas , Genoma de Planta , Meiose
16.
PLoS Pathog ; 13(5): e1006384, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28475642

RESUMO

A number of nonclassical MHC Ib molecules recognizing distinct microbial antigens have been implicated in the immune response to Mycobacterium tuberculosis (Mtb). HLA-E has been identified to present numerous Mtb peptides to CD8+ T cells, with multiple HLA-E-restricted cytotoxic T lymphocyte (CTL) and regulatory T cell lines isolated from patients with active and latent tuberculosis (TB). In other disease models, HLA-E and its mouse homolog Qa-1 can act as antigen presenting molecules as well as regulators of the immune response. However, it is unclear what precise role(s) HLA-E/Qa-1 play in the immune response to Mtb. In this study, we found that murine Qa-1 can bind and present Mtb peptide antigens to CD8+ T effector cells during aerosol Mtb infection. Further, mice lacking Qa-1 (Qa-1-/-) were more susceptible to high-dose Mtb infection compared to wild-type controls, with higher bacterial burdens and increased mortality. The increased susceptibility of Qa-1-/- mice was associated with dysregulated T cells that were more activated and produced higher levels of pro-inflammatory cytokines. T cells from Qa-1-/- mice also had increased expression of inhibitory and apoptosis-associated cell surface markers such as CD94/NKG2A, KLRG1, PD-1, Fas-L, and CTLA-4. As such, they were more prone to cell death and had decreased capacity in promoting the killing of Mtb in infected macrophages. Lastly, comparing the immune responses of Qa-1 mutant knock-in mice deficient in either Qa-1-restricted CD8+ Tregs (Qa-1 D227K) or the inhibitory Qa-1-CD94/NKG2A interaction (Qa-1 R72A) with Qa-1-/- and wild-type controls indicated that both of these Qa-1-mediated mechanisms were involved in suppression of the immune response in Mtb infection. Our findings reveal that Qa-1 participates in the immune response to Mtb infection by presenting peptide antigens as well as regulating immune responses, resulting in more effective anti-Mtb immunity.


Assuntos
Antígenos de Bactérias/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/microbiologia , Animais , Apresentação de Antígeno/imunologia , Citocinas/imunologia , Humanos , Macrófagos/imunologia , Camundongos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia , Tuberculose/imunologia
17.
J Biol Chem ; 292(3): 1112-1121, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-27986811

RESUMO

Eph receptors, the largest subfamily of transmembrane tyrosine kinase receptors, have been increasingly implicated in various physiologic and pathologic processes, and the roles of the Eph family members during tumorigenesis have recently attracted growing attentions. In the present study, we explored the function of EphB3, one member of Eph family, in papillary thyroid cancer (PTC). We found that the expression of EphB3 was significantly elevated in PTC. Either overexpression of EphB3 or activation of EphB3 by EfnB1-Fc/EfnB2-Fc stimulated in vitro migration of PTC cells. In contrast, siRNA-mediated knockdown of EphB3 or EphB3-Fc treatment, which only blocked EphB3-mediated forward signaling, inhibited migration and metastasis of PTC cells. A mechanism study revealed that EphB3 knockdown led to suppressed activity of Rac1 and enhanced activity of RhoA. Moreover, we found that Vav2, an important regulator of Rho family GTPases, was activated by EphB3 in a kinase-dependent manner. Altogether, our work suggested that EphB3 acted as a tumor promoter in PTC by increasing the in vitro migration as well as the in vivo metastasis of PTC cells through regulating the activities of Vav2 and Rho GTPases in a kinase-dependent manner.


Assuntos
Carcinoma/metabolismo , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-vav/metabolismo , Receptor EphB3/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Carcinoma/genética , Carcinoma/patologia , Carcinoma Papilar , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Metástase Neoplásica , Proteínas Proto-Oncogênicas c-vav/genética , Receptor EphB3/genética , Transdução de Sinais/genética , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Proteínas rac1 de Ligação ao GTP/genética
18.
PLoS Pathog ; 12(6): e1005688, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27272249

RESUMO

MHC Ib-restricted CD8+ T cells have been implicated in host defense against Mycobacterium tuberculosis (Mtb) infection. However, the relative contribution of various MHC Ib-restricted T cell populations to anti-mycobacterial immunity remains elusive. In this study, we used mice that lack MHC Ia (Kb-/-Db-/-), MHC Ia/H2-M3 (Kb-/-Db-/-M3-/-), or ß2m (ß2m-/-) to study the role of M3-restricted and other MHC Ib-restricted T cells in immunity against Mtb. Unlike their dominant role in Listeria infection, we found that M3-restricted CD8+ T cells only represented a small proportion of the CD8+ T cells responding to Mtb infection. Non-M3, MHC Ib-restricted CD8+ T cells expanded preferentially in the lungs of Mtb-infected Kb-/-Db-/-M3-/- mice, exhibited polyfunctional capacities and conferred protection against Mtb. These MHC Ib-restricted CD8+ T cells recognized several Mtb-derived protein antigens at a higher frequency than MHC Ia-restricted CD8+ T cells. The presentation of Mtb antigens to MHC Ib-restricted CD8+ T cells was mostly ß2m-dependent but TAP-independent. Interestingly, a large proportion of Mtb-specific MHC Ib-restricted CD8+ T cells in Kb-/-Db-/-M3-/- mice were Qa-2-restricted while no considerable numbers of MR1 or CD1-restricted Mtb-specific CD8+ T cells were detected. Our findings indicate that nonclassical CD8+ T cells other than the known M3, CD1, and MR1-restricted CD8+ T cells contribute to host immune responses against Mtb infection. Targeting these MHC Ib-restricted CD8+ T cells would facilitate the design of better Mtb vaccines with broader coverage across MHC haplotypes due to the limited polymorphism of MHC class Ib molecules.


Assuntos
Antígenos de Bactérias/imunologia , Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica/imunologia , Subpopulações de Linfócitos T/imunologia , Tuberculose/imunologia , Animais , Modelos Animais de Doenças , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe I , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Mycobacterium tuberculosis/imunologia , Reação em Cadeia da Polimerase em Tempo Real
19.
Elife ; 42015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26652001

RESUMO

Group 1 CD1 molecules, CD1a, CD1b and CD1c, present lipid antigens from Mycobacterium tuberculosis (Mtb) to T cells. Mtb lipid-specific group 1 CD1-restricted T cells have been detected in Mtb-infected individuals. However, their role in protective immunity against Mtb remains unclear due to the absence of group 1 CD1 expression in mice. To overcome the challenge, we generated mice that expressed human group 1 CD1 molecules (hCD1Tg) and a CD1b-restricted, mycolic-acid specific TCR (DN1Tg). Using DN1Tg/hCD1Tg mice, we found that activation of DN1 T cells was initiated in the mediastinal lymph nodes and showed faster kinetics compared to Mtb Ag85B-specific CD4(+) T cells after aerosol infection with Mtb. Additionally, activated DN1 T cells exhibited polyfunctional characteristics, accumulated in lung granulomas, and protected against Mtb infection. Therefore, our findings highlight the vaccination potential of targeting group 1 CD1-restricted lipid-specific T cells against Mtb infection.


Assuntos
Mycobacterium tuberculosis/imunologia , Ácidos Micólicos/imunologia , Subpopulações de Linfócitos T/imunologia , Tuberculose/imunologia , Animais , Antígenos de Bactérias/imunologia , Antígenos CD1/genética , Antígenos CD1/metabolismo , Humanos , Ativação Linfocitária , Camundongos , Camundongos SCID , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo
20.
Pak J Pharm Sci ; 28(3 Suppl): 1049-54, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26051723

RESUMO

Adhesion-related complications after abdominal surgery bring out momentous morbidity and costs. Outcomes from animal experiments investigating prevention of adhesions are limited due to lack of consistency in existing animal models. Different intraperitoneal adhesion models were compared the inter observer variability was evaluated to seek for best model. Forty male SD rats weighting 250-300g were included and assigned randomly to four groups with diverse techniques, (A) postoperative adhesion cecum rat model abraded with sterile rasp; (B) postoperative adhesion cecum rat model abraded with sterile dry gauze; (C) postoperative adhesion cecum rat model abraded with sterile blade; (D) postoperative adhesion cecum rat model abraded with vascular clamp. Macroscopic adhesion scores were evaluated by Bigatti scoring system, and the incidence of adhesion were surveyed on the 7th day after the surgery. The results showed that four techniques currently used Bigatti adhesion scoring system are subjective, the sterile rasp is the most consistent and reproducible tool to establish an intraperitoneal adhesion model which is helpful for related studies and the development of new substances for adhesion prevention in the future.


Assuntos
Ceco/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Doenças Peritoneais/etiologia , Animais , Modelos Animais de Doenças , Masculino , Doenças Peritoneais/patologia , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Fatores de Tempo , Aderências Teciduais
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