Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Plant Cell ; 36(3): 626-641, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-37950906

RESUMO

Sphingolipids are components of plant membranes, and their heterogeneous distribution gives different membrane systems distinct properties. For example, glycosyl inositol phosphoceramides (GIPCs), 1 major type of sphingolipids, aggregate in the outer layer of the plasma membrane (PM), as well as in extracellular vesicles (EVs), including the small (30 to 100 nm) EVs termed exosomes. How these sphingolipids are sorted and trafficked is not clear. In this work, we report that Arabidopsis thaliana TETRASPANIN8 (TET8) acts as a sphingolipid carrier and thus regulates the export of GIPCs from the Golgi apparatus. TET8 recognized the coat protein complex I (COPI) subunit γ2-COPI and moved to its proper location in the PM; this recognition required the TET8 C-terminal tail. Deleting the C-terminal tail of TET8 largely restricted its roles in GIPC transport and endosomal trafficking. Further, we show that TET8 affects EV secretion in association with GIPCs. Thus, our findings shed light on GIPC transport and the molecular machinery involved in EV biogenesis.


Assuntos
Arabidopsis , Exossomos , Arabidopsis/genética , Arabidopsis/metabolismo , Exossomos/metabolismo , Inositol/metabolismo , Esfingolipídeos , Complexo I de Proteína do Envoltório/metabolismo
2.
J Biol Chem ; : 107568, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019215

RESUMO

Acid-sensing ion Channel 1 (Asic1) is critical in acidotoxicity and significantly contributes to neuronal death in cerebral stroke. Pharmacological inhibition of Asic1 has been shown to reduce neuronal death. However, the potential of utilising exosomes derived from pluripotent stem cells to achieve inhibition of Asic1 remains to be explored. Developing qualified exosome products with precise and potent active ingredients suitable for clinical application is also ongoing. Here, we adopt small RNA sequencing to interrogate the miRNA contents in pluripotent stem cell-derived induced Mesenchymal Stem Cell (iMSC) derived exosomes. RNAseq was used to compare the oxygen-glucose deprivation (OGD)-damaged neurons before and after the delivery of exosomes. We used western blot to quantify the Asic1 protein abundance in neurons before and after exosome treatment. An in vivo test on rats validated the neuroprotective effect of iMSC-derived exosome and its active potent miRNA hsa-mir-125b-5p. We demonstrate that pluripotent stem cell-derived iMSCs produce exosomes with consistent miRNA contents and sustained expression. These exosomes efficiently rescue injured neurons, alleviate the pathological burden and restore neuron function in rats under oxygen-glucose deprivation (OGD) stress. Furthermore, we identify hsa-mir-125b-5p as the active component responsible for inhibiting the Asic1a protein and protecting neurons. We validated a novel therapeutic strategy to enhance acidosis resilience in cerebral stroke by utilising exosomes derived from pluripotent stem cells with specific miRNA content. This holds promise for cerebral stroke treatment with the potential to reduce neuronal damage and improve clinical patient outcomes.

3.
Diabet Med ; 41(4): e15268, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38140919

RESUMO

AIMS: There is limited research on the relationship between food insecurity and mortality among individuals with diabetes. This study aims to investigate the impact of food insecurity on all-cause and cause-specific mortality in adults with diabetes. RESEARCH DESIGN AND METHODS: This study included 5749 adults with diabetes from the National Health and Nutrition Examination Survey cycles 2003-2018 and followed up until 31 December 2019. Food insecurity was measured by the Food Security Survey Module. Cox proportional hazard models were employed to estimate hazard ratios (HRs) and 95% confidence intervals for both all-cause mortality and cause-specific mortality. RESULTS: The weighted prevalence of full food security, marginal food security, low food security, and very low food security was 70.8%, 11.0%, 10.4%, and 7.8%, respectively. Food insecurity demonstrated a significant correlation with diminished diet quality and reduced consumption of healthy foods. Over the course of 42,272.0 person-years of follow-up, we documented 1091 deaths, of which 370 were attributed to cardiovascular disease and 180 to cancer. After adjusting for multiple variables, food insecurity scores were significantly and linearly associated with increased all-cause mortality. Comparing to full food security, participants experiencing very low food security had a multivariate-adjusted HR of 1.48 (1.12, 1.95) for all-cause mortality (ptrend = 0.010). CONCLUSIONS: Food insecurity was associated with increased all-cause mortality and compromised diet quality, especially in individuals experiencing very low food security. Future strategies may necessitate the monitoring of and interventions for food insecurity among individuals with diabetes.


Assuntos
Diabetes Mellitus , Abastecimento de Alimentos , Adulto , Humanos , Inquéritos Nutricionais , Estudos Retrospectivos , Diabetes Mellitus/epidemiologia , Insegurança Alimentar
4.
Nat Chem Biol ; 16(3): 250-256, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31932723

RESUMO

In plants, lineage-specific metabolites can be created by activities derived from the catalytic promiscuity of ancestral proteins, although examples of recruiting detoxification systems to biosynthetic pathways are scarce. The ubiquitous glyoxalase (GLX) system scavenges the cytotoxic methylglyoxal, in which GLXI isomerizes the α-hydroxy carbonyl in the methylglyoxal-glutathione adduct for subsequent hydrolysis. We show that GLXIs across kingdoms are more promiscuous than recognized previously and can act as aromatases without cofactors. In cotton, a specialized GLXI variant, SPG, has lost its GSH-binding sites and organelle-targeting signal, and evolved to aromatize cyclic sesquiterpenes bearing α-hydroxyketones to synthesize defense compounds in the cytosol. Notably, SPG is able to transform acetylated deoxynivalenol, the prevalent mycotoxin contaminating cereals and foods. We propose that detoxification enzymes are a valuable source of new catalytic functions and SPG, a standalone enzyme catalyzing complex reactions, has potential for toxin degradation, crop engineering and design of novel aromatics.


Assuntos
Aromatase/metabolismo , Lactoilglutationa Liase/química , Lactoilglutationa Liase/metabolismo , Aromatase/química , Produtos Biológicos , Catálise , Citosol/metabolismo , Glutationa/metabolismo , Gossypium/metabolismo , Complexos Multienzimáticos , Aldeído Pirúvico/química , Aldeído Pirúvico/metabolismo
5.
Proc Natl Acad Sci U S A ; 116(28): 14331-14338, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31221756

RESUMO

Insects have evolved effectors to conquer plant defense. Most known insect effectors are isolated from sucking insects, and examples from chewing insects are limited. Moreover, the targets of insect effectors in host plants remain unknown. Here, we address a chewing insect effector and its working mechanism. Cotton bollworm (Helicoverpa armigera) is a lepidopteran insect widely existing in nature and severely affecting crop productivity. We isolated an effector named HARP1 from H. armigera oral secretion (OS). HARP1 was released from larvae to plant leaves during feeding and entered into the plant cells through wounding sites. Expression of HARP1 in Arabidopsis mitigated the global expression of wounding and jasmonate (JA) responsive genes and rendered the plants more susceptible to insect feeding. HARP1 directly interacted with JASMONATE-ZIM-domain (JAZ) repressors to prevent the COI1-mediated JAZ degradation, thus blocking JA signaling transduction. HARP1-like proteins have conserved function as effectors in noctuidae, and these types of effectors might contribute to insect adaptation to host plants during coevolution.


Assuntos
Gossypium/genética , Interações Hospedeiro-Parasita/genética , Mariposas/patogenicidade , Doenças das Plantas/genética , Animais , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Ciclopentanos/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/genética , Gossypium/crescimento & desenvolvimento , Gossypium/parasitologia , Mariposas/metabolismo , Oxilipinas/metabolismo , Doenças das Plantas/parasitologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Transdução de Sinais/genética
6.
Antimicrob Agents Chemother ; 65(12): e0029121, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34516252

RESUMO

Aspergillus fumigatus causes a series of invasive diseases, including the high-mortality invasive aspergillosis, and has been a serious global health threat because of its increased resistance to the first-line clinical triazoles. We analyzed the whole-genome sequence of 15 A. fumigatus strains from China and found that long terminal repeat retrotransposons (LTR-RTs), including Afut1, Afut2, Afut3, and Afut4, are most common and have the largest total nucleotide length among all transposable elements in A. fumigatus. Deleting one of the most enriched Afut4977-sac1 in azole-resistant strains decreased azole resistance and downregulated its nearby gene, sac1, but it did not significantly affect the expression of genes of the ergosterol synthesis pathway. We then discovered that 5'LTR of Afut4977-sac1 had promoter activity and enhanced the adjacent sac1 gene expression. We found that sac1 is important to A. fumigatus, and the upregulated sac1 caused elevated resistance of A. fumigatus to azoles. Finally, we showed that Afut4977-sac1 has an evolution pattern similar to that of the whole genome of azole-resistant strains due to azoles; phylogenetic analysis of both the whole genome and Afut4977-sac1 suggests that the insertion of Afut4977-sac1 might have preceded the emergence of azole-resistant strains. Taking these data together, we found that the Afut4977-sac1 LTR-RT might be involved in the regulation of azole resistance of A. fumigatus by upregulating its nearby sac1 gene.


Assuntos
Aspergillus fumigatus , Azóis , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergillus fumigatus/genética , Azóis/farmacologia , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Testes de Sensibilidade Microbiana , Filogenia , Retroelementos/genética , Sequências Repetidas Terminais/genética
7.
Environ Microbiol ; 23(12): 7373-7381, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34347340

RESUMO

Coronavirus disease 2019 (COVID-19) pandemic has caused high number of infections and deaths of healthcare workers globally. Distribution and possible transmission route of SARS-CoV-2 in hospital environment should be clarified. We herein collected 431 environmental (391 surface and 40 air) samples in the intensive care unit (ICU) and general wards (GWs) of three hospitals in Wuhan, China from February 21 to March 4, 2020, and detected SARS-CoV-2 RNA by real-time quantitative PCR. The viral positive rate in the contaminated areas was 17.8% (28/157), whereas there was no virus detected in the clean areas. Higher positive rate (22/59, 37.3%) was found in ICU than that in GWs (3/63, 4.8%). The surfaces of computer keyboards and mouse in the ICU were the most contaminated (8/10, 80.0%), followed by the ground (6/9, 66.7%) and outer glove (2/5, 40.0%). From 17 air samples in the contaminated areas, only one sample collected at a distance of around 30 cm from the patient was positive. Enhanced surface disinfection and hand hygiene effectively decontaminated the virus from the environment. This finding might help understand the transmission route and contamination risk of SARS-CoV-2 and evaluate the effectiveness of infection prevention and control measures in healthcare facilities.


Assuntos
COVID-19 , Hospitais , Humanos , Pandemias , RNA Viral/genética , SARS-CoV-2
8.
Artigo em Inglês | MEDLINE | ID: mdl-29483117

RESUMO

Through some specific amino acid residues, cofilin, a ubiquitous actin depolymerization factor, can significantly affect mitochondrial function related to drug resistance and apoptosis in Saccharomyces cerevisiae; however, this modulation in a major fungal pathogen, Aspergillus fumigatus, was still unclear. Hereby, it was found, first, that mutations on several charged residues in cofilin to alanine, D19A-R21A, E48A, and K36A, increased the formation of reactive oxygen species and induced apoptosis along with typical hallmarks, including mitochondrial membrane potential depolarization, cytochrome c release, upregulation of metacaspases, and DNA cleavage, in A. fumigatus Two of these mutations (D19A-R21A and K36A) increased acetyl coenzyme A and ATP concentrations by triggering fatty acid ß-oxidation. The upregulated acetyl coenzyme A affected the ergosterol biosynthetic pathway, leading to overexpression of cyp51A and -B, while excess ATP fueled ATP-binding cassette transporters. Besides, both of these mutations reduced the susceptibility of A. fumigatus to azole drugs and enhanced the virulence of A. fumigatus in a Galleria mellonella infection model. Taken together, novel and key charged residues in cofilin were identified to be essential modules regulating the mitochondrial function involved in azole susceptibility, apoptosis, and virulence of A. fumigatus.


Assuntos
Fatores de Despolimerização de Actina/genética , Antifúngicos/farmacologia , Apoptose/genética , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Azóis/farmacologia , Farmacorresistência Fúngica/genética , Mitocôndrias/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Acetilcoenzima A/biossíntese , Aspergillus fumigatus/patogenicidade , Sistema Enzimático do Citocromo P-450/biossíntese , Ergosterol/biossíntese , Proteínas Fúngicas/biossíntese , Humanos , Virulência/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-29507067

RESUMO

The use of azole fungicides in agriculture is believed to be one of the main reasons for the emergence of azole resistance in Aspergillus fumigatus Though widely used in agriculture, imidazole fungicides have not been linked to resistance in A. fumigatus This study showed that elevated MIC values of imidazole drugs were observed against A. fumigatus isolates with TR34/L98H/S297T/F495I mutation, but not among isolates with TR34/L98H mutation. Short-tandem-repeat (STR) typing analysis of 580 A. fumigatus isolates from 20 countries suggested that the majority of TR34/L98H/S297T/F495I strains from China were genetically different from the predominant major clade comprising most of the azole-resistant strains and the strains with the same mutation from the Netherlands and Denmark. Alignments of sterol 14α-demethylase sequences suggested that F495I in A. fumigatus was orthologous to F506I in Penicillium digitatum and F489L in Pyrenophora teres, which have been reported to be associated with imidazole resistance. In vitro antifungal susceptibility testing of different recombinants with cyp51A mutations further confirmed the association of the F495I mutation with imidazole resistance. In conclusion, this study suggested that environmental use of imidazole fungicides might confer selection pressure for the emergence of azole resistance in A. fumigatus.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Imidazóis/farmacologia , Esterol 14-Desmetilase/genética , Agricultura/métodos , Sequência de Aminoácidos , Aspergilose/tratamento farmacológico , Aspergillus fumigatus/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Seleção Genética/genética , Alinhamento de Sequência
10.
Fungal Genet Biol ; 120: 30-41, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30205199

RESUMO

Aspergillus fumigatus is a major pathogen of invasive pulmonary aspergillosis. The small GTPase, Rho1, of A. fumigatus is reported to comprise a potential regulatory subunit of ß-1,3-glucan synthase and is indispensable for fungal viability; however, the role of AfRho1 on the growth, cell wall integrity, and pathogenesis of A. fumigatus is still poorly understood. We constructed A. fumigatus mutants with conditional- and overexpression of Rho1 and found that defects of AfRho1 expression led to the reduction of ß-1,3-glucan and glucosamine moieties on the cell wall, with down-regulated transcription of genes in the cell wall integrity signaling pathway and a decrease of calcofluor white (CFW)-stimulated mitogen-activated protein kinase (MpkA) phosphorylation and cytoplasmic leakage compared to those of the wild-type strain (WT). In addition, down-regulation of AfRho1 expression caused much higher sensitivity of A. fumigatus to H2O2 and alkaline pH compared to that of WT. Decrease of AfRho1 expression also attenuated the A. fumigatus pathogenicity in Galleria mellonella and inhibited conidial internalization into lung epithelial cells and inflammatory factor release. In contrast, overexpression of Rho1 did not alter A. fumigatus morphology, susceptibility to cell wall stresses, or pathogenicity relative to its parental strain. Taken together, our findings support AfRho1 as an essential regulator of the cell wall integrity, stress response, and pathogenesis of A. fumigatus.


Assuntos
Aspergillus fumigatus/enzimologia , Parede Celular/fisiologia , Proteínas Fúngicas/fisiologia , Proteínas rho de Ligação ao GTP/fisiologia , Células A549 , Animais , Aspergilose/microbiologia , Aspergillus fumigatus/patogenicidade , Aspergillus fumigatus/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mariposas/microbiologia , Estresse Fisiológico , Virulência/genética
11.
Microb Pathog ; 123: 169-176, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30017941

RESUMO

The destruction of pulmonary epithelium is a major feature of lung diseases caused by the fungal pathogen Aspergillus fumigatus (A. fumigatus). Gliotoxin, a major mycotoxin of A. fumigatus, is widely postulated to be associated with the tissue invasion. However, the mechanism is unclear. In this study, we first discovered that cofilin, a regulator of actin dynamics in the pulmonary epithelial cells, existed mainly in the form of oligomer, which kept it unable to depolymerize actin filaments. Gliotoxin could reduce the formation of cofilin oligomer and promote the release of active cofilin monomer by regulating cofilin phosphorylation balance. Then, the active cofilin induced the dissolution of actin stress fibers to result in the disruption of pulmonary epithelium barrier function. Collectively, our study revealed a novel mechanism of gliotoxin destructing lung epithelium barrier function and for the first time indicated the role of cofilin oligomer in this process.


Assuntos
Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Gliotoxina/toxicidade , Pulmão/efeitos dos fármacos , Fibras de Estresse/metabolismo , Células A549/efeitos dos fármacos , Animais , Aspergillus fumigatus/patogenicidade , Linhagem Celular/efeitos dos fármacos , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Humanos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Solubilidade
12.
BMC Infect Dis ; 18(1): 491, 2018 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-30268099

RESUMO

BACKGROUND: Carbapenem resistance in Acinetobacter baumannii in China was mainly mediated by OXA-23-like carbapenemases, while OXA-24/40-like carbapenemases were rarely identified. OXA-72 is one variant of OXA-24/40-like carbapenemases. This study aimed to demonstrate the epidemiology and characterizations of OXA-72-producing A. baumannii in a Chinese hospital. METHODS: A total of 107 clinical A. calcoaceticus-A. baumannii (Acb) complex isolates were collected in a Chinese hospital during between 2014 and 2016. These isolates were identified using Vitek 2 system and gyrB multiplex PCR. Vitek 2 system was used for antibiotic susceptibility testing. Genes encoding for major classes of carbapenemases were investigated by PCR. Rep-PCR was used for genotyping of all the A. baumannii isolates. The risk factors for carriage of OXA-72-producing or OXA-23-producing A. baumannii were analyzed through univariate and multivariate logistic regression. RESULTS: Of the 107 Acb isolates collected, 101 isolates (94.4%) and 6 isolates (5.6%) were identified as A. baumannii and A. pittii, respectively. 78 A. baumannii isolates (77.2%) were carbapenem resistant and mainly cultured from intensive care unit (ICU). blaOXA-72 and blaOXA-23 genes were identified in 45(57.7%) and 33(42.3%) carbapenem-resistant A. baumannii (CRAB), respectively. Multivariate risk factor analyses showed that prior carbapenem usage and nasogastric intubation were significantly associated with carriage of OXA-72-producing A. baumannii or OXA-23-producing A. baumannii. Rep-PCR analysis showed that 9 and 22 Rep-PCR types were assigned to 78 CRAB isolates and 23 carbapenem-susceptible A. baumannii (CSAB) isolates, respectively. A higher diverstiy of Rep-PCR patterns was observed among OXA-72-producing A. baumannii isolates than OXA-23-producing A. baumannii isolates, but all of them belonged to the same clone complex. MLST analysis suggested that the OXA-72 isolates from this study correspond to CC92/CC2 clone complex. CONCLUSIONS: This study demonstrates high prevalence and potential clonal spread of closely related genotypes of OXA-72-producing A. baumannii within a Chinese hospital. Continuous surveillance is necessary to monitor the dissemination of these strains in other healthcare settings to guide infection control policies in order to curb the spread of this bacterium.


Assuntos
Infecções por Acinetobacter/diagnóstico , Acinetobacter baumannii/metabolismo , Proteínas de Bactérias/genética , beta-Lactamases/genética , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , China/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana/genética , Feminino , Humanos , Unidades de Terapia Intensiva , Modelos Logísticos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Adulto Jovem , beta-Lactamases/metabolismo
13.
Antimicrob Agents Chemother ; 60(10): 5878-84, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27431231

RESUMO

Azole resistance in Aspergillus fumigatus has emerged as a worldwide public health problem. We sought here to demonstrate the occurrence and characteristics of azole resistance in A. fumigatus from different parts of China. A total of 317 clinical and 144 environmental A. fumigatus isolates from 12 provinces were collected and subjected to screening for azole resistance. Antifungal susceptibility, cyp51A gene sequencing, and genotyping were carried out for all suspected azole-resistant isolates and a subset of azole-susceptible isolates. As a result, 8 (2.5%) clinical and 2 (1.4%) environmental A. fumigatus isolates were identified as azole resistant. Five azole-resistant strains exhibit the TR34/L98H mutation, whereas four carry the TR34/L98H/S297T/F495I mutation in the cyp51A gene. Genetic typing and phylogenetic analysis showed that there was a worldwide clonal expansion of the TR34/L98H isolates, while the TR34/L98H/S297T/F495I isolates from China harbored a distinct genetic background with resistant isolates from other countries. High polymorphisms existed in the cyp51A gene that produced amino acid changes among azole-susceptible A. fumigatus isolates, with N248K being the most common mutation. These data suggest that the wide distribution of azole-resistant A. fumigatus might be attributed to the environmental resistance mechanisms in China.


Assuntos
Antifúngicos/farmacologia , Aspergilose/epidemiologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Farmacorresistência Fúngica/efeitos dos fármacos , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Aspergillus fumigatus/isolamento & purificação , Azóis/farmacologia , China/epidemiologia , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Humanos , Repetições de Microssatélites , Filogenia
14.
BMC Microbiol ; 15: 161, 2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26268695

RESUMO

BACKGROUND: The internalization of Aspergillus fumigatus into alveolar epithelial cells (AECs) is tightly controlled by host cellular actin dynamics, which require close modulation of the ADF (actin depolymerizing factor)/cofilin family. However, the role of cofilin in A. fumigatus internalization into AECs remains unclear. RESULTS: Here, we demonstrated that germinated A. fumigatus conidia were able to induce phosphorylation of cofilin in A549 cells during the early stage of internalization. The modulation of cofilin activity by overexpression, knockdown, or mutation of the cofilin gene in A549 cells decreased the efficacy of A. fumigatus internalization. Reducing the phosphorylation status of cofilin with BMS-5 (LIM kinase inhibitor) or overexpression of the slingshot phosphatases also impeded A. fumigatus internalization. Both the C. botulimun C3 transferase (a specific RhoA inhibitor) and Y27632 (a specific ROCK inhibitor) reduced the internalization of A. fumigatus and the level of phosphorylated cofilin. ß-1,3-glucan (the major component of the conidial cell wall) and its host cell receptor dectin-1 did not seem to be associated with cofilin phosphorylation during A. fumigatus infection. CONCLUSION: These results indicated that cofilin might be involved in the modulation of A. fumigatus internalization into type II alveolar epithelial cells through the RhoA-ROCK-LIM kinase pathway.


Assuntos
Fatores de Despolimerização de Actina/metabolismo , Aspergillus fumigatus/fisiologia , Endocitose , Células Epiteliais/microbiologia , Interações Hospedeiro-Patógeno , Linhagem Celular , Humanos
15.
Wei Sheng Wu Xue Bao ; 55(12): 1537-42, 2015 Dec 04.
Artigo em Chinês | MEDLINE | ID: mdl-27101695

RESUMO

Invasion of pathogens into host cells is the key process to consequently induce the infection, which depends on the actin cytoskeleton rearrangement. Cofilin in the host cell is one of the most important actin depolymerization factor that is essential responsing to the infection of several viruses, bacteria and fungi. Pathogenic microbes can induce biphasic remodeling of the actin cytoskeleton in host cells, accompanied by changes of phosphorylation of cofilin, which results in changes of cofilin activity. The modulation of host cofilin activity by mutation, knockdown, or overexpression can effectively inhibit the infection. Here we review the function and possible regulatory mechanism of host cofilin during the process of infection.


Assuntos
Fatores de Despolimerização de Actina/metabolismo , Infecções Bacterianas/metabolismo , Fungos/fisiologia , Interações Hospedeiro-Patógeno , Micoses/metabolismo , Micoses/microbiologia , Fatores de Despolimerização de Actina/genética , Animais , Infecções Bacterianas/genética , Infecções Bacterianas/microbiologia , Fenômenos Fisiológicos Bacterianos , Humanos , Micoses/genética
16.
Proteomics ; 14(17-18): 1977-86, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24995952

RESUMO

Activated hepatic stellate cell (HSC) is the main myofibroblast cell in the liver fibrosis (LF). An important characteristic of the recovery of LF is not only the apoptosis of activated HSCs but also reversal of myofibroblast-like phenotype to a quiescent-like phenotype. Understanding the changes of secreted proteins in the reversion of activated HSCs may provide the broader view of cellular regulatory networks and discover candidate markers or targets for therapeutic strategies of LF. In this study, stable isotope labeling with amino acids (SILAC) combined with linear ion trap-Fourier transform ion cyclotron resonance mass spectrometer (LTQ-FT MS) was performed on in vitro activated HSCs and reverted HSCs to obtain a proteomic view of secretory proteins. In total, 330 proteins showed significant differences in reverted HSCs. Among these, 109 upregulated proteins were mainly involved in amino acid metabolism pathway and glucose metabolism pathway using GeneGO/MetaCore software, while 221 downregulated proteins are closely associated with HSCs activation, such as cytoskeleton remodeling, chemokines, and cell adhesion. Additionally, a set of novel proteins associated with HSCs activation and reversion were validated by Western blotting in the cell secretion and in the sera of LF, including vitronectin, laminin beta 1, and ubiquitin conjugation factor E4B. Our study provided the valuable insight into the mechanisms in the reversion of activated HSCs and identified some potential biomarkers of LF in clinical studies. All MS data have been deposited in the ProteomeXchange with identifier PXD000773 (http://proteomecentral.proteomexchange.org/dataset/PXD000773).


Assuntos
Células Estreladas do Fígado/metabolismo , Marcação por Isótopo/métodos , Proteoma/análise , Proteoma/química , Proteômica/métodos , Western Blotting , Linhagem Celular , Células Estreladas do Fígado/química , Humanos , Espectrometria de Massas/métodos , Proteínas/análise , Proteínas/química , Proteínas/classificação , Reprodutibilidade dos Testes
17.
Front Plant Sci ; 15: 1361959, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38576787

RESUMO

Artemisinin biosynthesis, unique to Artemisia annua, is suggested to have evolved from the ancestral costunolide biosynthetic pathway commonly found in the Asteraceae family. However, the evolutionary landscape of this process is not fully understood. The first oxidase in artemisinin biosynthesis, CYP71AV1, also known as amorpha-4,11-diene oxidase (AMO), has specialized from ancestral germacrene A oxidases (GAOs). Unlike GAO, which exhibits catalytic promiscuity toward amorpha-4,11-diene, the natural substrate of AMO, AMO has lost its ancestral activity on germacrene A. Previous studies have suggested that the loss of the GAO copy in A. annua is responsible for the abolishment of the costunolide pathway. In the genome of A. annua, there are two copies of AMO, each of which has been reported to be responsible for the different product profiles of high- and low-artemisinin production chemotypes. Through analysis of their tissue-specific expression and comparison of their sequences with those of other GAOs, it was discovered that one copy of AMO (AMOHAP) exhibits a different transcript compared to the reported artemisinin biosynthetic genes and shows more sequence similarity to other GAOs in the catalytic regions. Furthermore, in a subsequent in vitro enzymatic assay, the recombinant protein of AMOHAP unequivocally demonstrated GAO activity. This result clearly indicates that AMOHAP is a GAO rather than an AMO and that its promiscuous activity on amorpha-4,11-diene has led to its misidentification as an AMO in previous studies. In addition, the divergent expression pattern of AMOHAP compared to that of the upstream germacrene A synthase may have contributed to the abolishment of costunolide biosynthesis in A. annua. Our findings reveal a complex evolutionary landscape in which the emergence of a new metabolic pathway replaces an ancestral one.

18.
Clin Nutr ; 43(8): 1740-1750, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38924998

RESUMO

BACKGROUND: Uncertainties still existed about the effect of high-quality protein supplementation on cardiovascular disease (CVD) risk factors, although high-quality proteins such as soy and milk proteins have proposed to be beneficial for cardiometabolic health. METHODS: A systematic search in PubMed, Web of Science, Cochrane Library, Scopus, and Embase was conducted to quantify the impact of high-quality protein on CVD risk factors. RESULTS: 63 RCTs on 4 types of high-quality protein including soy protein, milk protein, whey, and casein were evaluated. Soy protein supplementation decreased systolic blood pressure (SBP, -1.42 [-2.68, -0.17] mmHg), total cholesterol (TC, -0.18 [-0.30, -0.07] mmol/L), and low-density lipoprotein cholesterol (LDL-C, -0.16 [-0.27, -0.05] mmol/L). Milk protein supplementation decreased SBP (-2.30 [-3.45, -1.15] mmHg) and total cholesterol (-0.27 [-0.51, -0.03] mmol/L). Whey supplementation decreased SBP (-2.20 [-3.89, -0.51] mmHg), diastolic blood pressure (DBP, -1.07 [-1.98, -0.16] mmHg), triglycerides (-0.10 [-0.17, -0.03] mmol/L), TC (-0.18 [-0.35, -0.01] mmol/L), LDL-C (-0.09 [-0.16, -0.01] mmol/L) and fasting blood insulin (FBI, -2.02 [-3.75, -0.29] pmol/L). Casein supplementation decreased SBP (-4.10 [-8.05, -0.14] mmHg). In the pooled analysis of four high-quality proteins, differential effects were seen in individuals with different health status. In hypertensive individuals, high-quality proteins decreased both SBP (-2.69 [-3.50, -1.87] mmHg) and DBP (-1.34 [-2.09, -0.60] mmHg). In overweight/obese individuals, high-quality proteins improved SBP (-1.40 [-2.22, -0.59] mmHg), DBP (-2.59 [-3.20, -1.98] mmHg), triglycerides (-0.09 [-0.15, -0.02] mmol/L), TC (-0.14 [-0.22, -0.05] mmol/L), LDL-C (-0.12 [-0.16, -0.07] mmol/L), and HDL-C levels (0.02 [0.01, 0.04] mmol/L). According to the benefits on CVD risks factors, whey ranked top for improving cardiometabolic health in hypertensive or overweight/obese individuals. CONCLUSION: Our study supports a beneficial role of high-quality protein supplementation to reduce CVD risk factors. Further studies are still warranted to investigate the effects of different high-quality proteins on CVD risks in individuals with cardiometabolic disorders.

19.
J Colloid Interface Sci ; 661: 840-852, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38330656

RESUMO

Magnetic carbon-based catalysts with environmental friendliness have exhibited prominent effects on advanced oxidation processes. Herein, a multi-level FeCo/N-doped carbon nanosheet (FeCo/CNS) was synthesized by facile impregnation iron-cobalt salt onto cotton and followed by confined pyrolysis. We identified excellent advantages of the modified FeCo/CNS materials: (i) The convenience of the synthesis method and (ii) The dual effect of sterilization and contaminant degradation achieved through the FeCo/CNS-activated Peroxymonosulfate (PMS). The comparative experimental showed that FeCo/CNS could provide favorable catalytic performance, completely removing bisphenol A (BPA) and tetracycline (TC) within 5 min. Moreover, the potent sterilization properties against Staphylococcus aureus and Escherichia coli were also verified. Analysis of the degradation pathway confirmed the existence of intermediates, and toxicological research demonstrated that the toxicity of the degradation intermediates of BPA gradually decreased over time. Our research provided an excellent application of FeCo/CNS in PMS oxidation and sterilization inactivation.


Assuntos
Compostos Benzidrílicos , Carbono , Compostos de Ferro , Fenóis , Peróxidos , Ferro
20.
Psychol Res Behav Manag ; 16: 521-533, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36855598

RESUMO

Introduction: Kindergarten teachers who empathize with toddlers experience a great risk of burnout and emotional disturbance. This is referred to as compassion fatigue, in which teachers' empathy experience is reduced. This study proposed a moderated mediation model to identify the risks of compassion fatigue and its protective factors for developing evidence-based clinical interventions. Methods: In this cross-sectional study, self-report measures were administered to 1049 kindergarten teachers to observe their mindsets toward children, motivation for teacher empathy, job stress, social support, and compassion fatigue. The PROCESS macro (SPSS 23.0) was used to assess the moderated mediation model. Results: The results demonstrated that motivation for teacher empathy mediated the negative relationship between kindergarten teachers' mindsets toward children and compassion fatigue. Moreover, job stress and social support moderated the relationship between kindergarten teachers' mindsets toward children and motivation for teacher empathy. However, this effect was not observed in the negative relationship between kindergarten teachers' mindsets toward children and compassion fatigue. Conclusion: The proposed moderated mediation model was found to be valid. Furthermore, the study findings have practical implications for developing evidence-based interventions for addressing kindergarten teachers' compassion fatigue.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa