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1.
Stem Cells ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804841

RESUMO

Cisplatin is widely employed in tumor chemotherapy, but nephrotoxicity is an unavoidable side effect of cisplatin. Several studies have demonstrated that mesenchymal stromal cells (MSCs) ameliorate cisplatin-induced kidney injury, but the underlying mechanisms are unknown. In this study, the cisplatin-induced kidney injury mouse model was established by subjecting a single intraperitoneal injection with cisplatin. One hour before cisplatin injection, the mice received human bone marrow MSCs (hBM-MSCs) with or without siRNA-transfection, recombinant human tumor necrosis factor (TNF)-α-stimulated gene/protein 6 (rhTSG-6), or PBS through tail vein. In addition, cisplatin-stimulated HK-2 cells were treated with hBM-MSCs or rhTSG-6. hBM-MSCs treatment remarkably ameliorated cisplatin-induced acute and chronic kidney injury, as evidenced by significant reductions in serum creatinine (Scr), blood urea nitrogen (BUN), tubular injury, collagen deposition, α-smooth muscle actin accumulation, as well as inflammatory responses, and by remarkable increased anti-inflammatory factor expression and Treg cells infiltration in renal tissues. Furthermore, we found that only a few hBM-MSCs engrafted into damaged kidney and that the level of human TSG-6 in serum of mice increased significantly following hBM-MSCs administration. Moreover, hBM-MSCs significantly increased the viability of damaged HK-2 cells and decreased the levels of inflammatory cytokines in the culture supernatant. However, knockdown of TSG-6 gene in hBM-MSCs significantly attenuated their beneficial effects in vivo and in vitro. On the contrary, treated with rhTSG-6 achieved similar beneficial effects of hBM-MSCs. Our results indicate that systemic administration of hBM-MSCs alleviate cisplatin-induced acute and chronic kidney injury in part by paracrine TSG-6 secretion.

2.
Biotechnol Bioeng ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38924076

RESUMO

In this study, a novel array electrospinning collector was devised to generate two distinct regenerated silk fibroin (SF) fibrous membranes: ordered and disordered. Leveraging electrostatic forces during the electrospinning process allowed precise control over the orientation of SF fiber, resulting in the creation of membranes comprising both aligned and randomly arranged fiber layers. This innovative approach resulted in the development of large-area membranes featuring exceptional stability due to their alternating patterned structure, achievable through expansion using the collector, and improving the aligned fiber membrane mechanical properties. The study delved into exploring the potential of these membranes in augmenting wound healing efficiency. Conducting in vitro toxicity assays with adipose tissue-derived mesenchymal stem cells (AD-MSCs) and normal human dermal fibroblasts (NHDFs) confirmed the biocompatibility of the SF membranes. We use dual perspectives on exploring the effects of different conditioned mediums produced by cells and structural cues of materials on NHDFs migration. The nanofibers providing the microenvironment can directly guide NHDFs migration and also affect the AD-MSCs and NHDFs paracrine effects, which can improve the chemotaxis of NHDFs migration. The ordered membrane, in particular, exhibited pronounced effectiveness in guiding directional cell migration. This research underscores the revelation that customizable microenvironments facilitated by SF membranes optimize the paracrine products of mesenchymal stem cells and offer valuable physical cues, presenting novel prospects for enhancing wound healing efficiency.

3.
J Chem Inf Model ; 64(13): 5207-5218, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38913174

RESUMO

Nirmatrelvir, a pivotal component of the oral antiviral Paxlovid for COVID-19, targets the SARS-CoV-2 main protease (Mpro) as a covalent inhibitor. Here, we employed combined computational methods to explore how the prevalent Omicron variant mutation P132H, alone and in combination with A173V (P132H-A173V), affects nirmatrelvir's efficacy. Our findings suggest that P132H enhances the noncovalent binding affinity of Mpro for nirmatrelvir, whereas P132H-A173V diminishes it. Although both mutants catalyze the rate-limiting step more efficiently than the wild-type (WT) Mpro, P132H slows the overall rate of covalent bond formation, whereas P132H-A173V accelerates it. Comprehensive analysis of noncovalent and covalent contributions to the overall binding free energy of the covalent complex suggests that P132H likely enhances Mpro sensitivity to nirmatrelvir, while P132H-A173V may confer resistance. Per-residue decompositions of the binding and activation free energies pinpoint key residues that significantly affect the binding affinity and reaction rates, revealing how the mutations modulate these effects. The mutation-induced conformational perturbations alter drug-protein local contact intensities and the electrostatic preorganization of the protein, affecting noncovalent binding affinity and the stability of key reaction states, respectively. Our findings inform the mechanisms of nirmatrelvir resistance and sensitivity, facilitating improved drug design and the detection of resistant strains.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Mutação , SARS-CoV-2 , SARS-CoV-2/enzimologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/química , Proteases 3C de Coronavírus/genética , Antivirais/farmacologia , Antivirais/química , Humanos , Tratamento Farmacológico da COVID-19 , Simulação de Dinâmica Molecular , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Leucina/química , Termodinâmica , Sulfonamidas/farmacologia , Sulfonamidas/química , Sulfonamidas/metabolismo , Ligação Proteica , Succinatos/química , Succinatos/farmacologia , Succinatos/metabolismo , Lactamas , Nitrilas , Prolina
4.
Child Dev ; 95(1): e21-e34, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37561124

RESUMO

Loneliness is a perceived deficit in social relationships that is nested within broader cultural meaning systems. This longitudinal study examined predictors of loneliness in Chinese and U.S. children with the hypothesis that peer relationship parameters (number of friends, social preference, and popularity) mediate the associations between behavior qualities and loneliness differently across countries. Fifth-grade Chinese (n = 576, Mage = 10.58 years) and U.S. (White, Black, Asian, n = 540; Mage = 10.23 years) children completed two waves of assessment within an academic year. Shyness and athletic competence more strongly predicted loneliness for U.S. children, and academic ability, and aggression more strongly predicted loneliness for Chinese children. Popularity was a mediator for U.S. children but not Chinese children.


Assuntos
Relações Interpessoais , Solidão , Criança , Humanos , Estados Unidos , Estudos Longitudinais , Grupo Associado , China
5.
PLoS Genet ; 17(3): e1009383, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33657091

RESUMO

As both host and pathogen require iron for survival, iron is an important regulator of host-pathogen interactions. However, the molecular mechanism by which how the availability of iron modulates host innate immunity against bacterial infections remains largely unknown. Using the metazoan Caenorhabditis elegans as a model, we demonstrate that infection with a pathogenic bacterium Salmonella enterica serovar Typhimurium induces autophagy by inactivating the target of rapamycin (TOR). Although the transcripts of ftn-1 and ftn-2 encoding two H-ferritin subunits are upregulated upon S. Typhimurium infection, the ferritin protein is kept at a low level due to its degradation mediated by autophagy. Autophagy, but not ferritin, is required for defense against S. Typhimurium infection under normal circumstances. Increased abundance of iron suppresses autophagy by activating TOR, leading to an increase in the ferritin protein level. Iron sequestration, but not autophagy, becomes pivotal to protect the host from S. Typhimurium infection in the presence of exogenous iron. Our results show that TOR acts as a regulator linking iron availability with host defense against bacterial infection.


Assuntos
Infecções Bacterianas/metabolismo , Sinais (Psicologia) , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Ferro/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagia , Infecções Bacterianas/etiologia , Caenorhabditis elegans , Resistência à Doença/genética , Suscetibilidade a Doenças , Ferritinas/metabolismo , Interações Hospedeiro-Patógeno/genética , Humanos , Modelos Biológicos , Salmonella typhimurium/imunologia
6.
J Biol Chem ; 298(3): 101637, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35085555

RESUMO

Adaptation to nutrient deprivation depends on the activation of metabolic programs to use reserves of energy. When outside a host plant, second-stage juveniles (J2) of the root-knot nematode (Meloidogyne spp.), an important group of pests responsible for severe losses in the production of crops (e.g., rice, wheat, and tomato), are unable to acquire food. Although lipid hydrolysis has been observed in J2 nematodes, its role in fitness and the underlying mechanisms remain unknown. Using RNA-seq analysis, here, we demonstrated that in the absence of host plants, the pathway for the biosynthesis of polyunsaturated fatty acids was upregulated, thereby increasing the production of arachidonic acid in middle-stage J2 Meloidogyne incognita worms. We also found that arachidonic acid upregulated the expression of the transcription factor hlh-30b, which in turn induced lysosomal biogenesis. Lysosomes promoted lipid hydrolysis via a lysosomal lipase, LIPL-1. Furthermore, our data demonstrated that blockage of lysosomal lipolysis reduced both lifespan and locomotion of J2 worms. Strikingly, disturbance of lysosomal lipolysis resulted in a decline in infectivity of these juveniles on tomato roots. Our findings not only reveal the molecular mechanism of lipolysis in J2 worms but also suggest potential novel strategies for the management of root-knot nematode pests.


Assuntos
Solanum lycopersicum , Tylenchoidea , Animais , Ácidos Araquidônicos/metabolismo , Metabolismo dos Lipídeos , Lipólise , Solanum lycopersicum/parasitologia , Lisossomos , Tylenchoidea/metabolismo , Tylenchoidea/fisiologia
7.
Nat Prod Rep ; 40(3): 646-675, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36597965

RESUMO

Covering: 2010 to 2021Natural nematicidal metabolites are important sources of nematode control. This review covers the isolation and structural determination of nematicidal metabolites from 2010 to 2021. We summarise chemical structures, bioactivity, metabolic regulation and biosynthesis of potential nematocides, and structure-activity relationship and application potentiality of natural metabolites in plant parasitic nematodes' biocontrol. In doing so, we aim to provide a comprehensive overview of the potential roles that natural metabolites can play in anti-nematode strategies.


Assuntos
Antinematódeos , Nematoides , Animais , Antinematódeos/farmacologia , Antinematódeos/metabolismo , Plantas/metabolismo
8.
Small ; 19(22): e2205833, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36876447

RESUMO

Thermochromic smart windows with rational modulation in indoor temperature and brightness draw considerable interest in reducing building energy consumption, which remains a huge challenge to meet the comfortable responsive temperature and the wide transmittance modulation range from visible to near-infrared (NIR) light for their practical application. Herein, a novel thermochromic Ni(II) organometallic of [(C2 H5 )2 NH2 ]2 NiCl4 for smart windows is rationally designed and synthesized via an inexpensive mechanochemistry method, which processes a low phase-transition temperature of 46.3 °C for the reversible color evolution from transparent to blue with a tunable visible transmittance from 90.5% to 72.1%. Furthermore, cesium tungsten bronze (CWO) and antimony tin oxide (ATO) with excellent NIR absorption in 750-1500 and 1500-2600 nm are introduced in the [(C2 H5 )2 NH2 ]2 NiCl4 -based smart windows, realizing a broadband sunlight modulation of a 27% visible light modulation and more than 90% of NIR shielding ability. Impressively, these smart windows demonstrate stable and reversible thermochromic cycles at room temperature. Compared with the conventional windows in the field tests, these smart windows can significantly reduce the indoor temperature by 16.1 °C, which is promising for next-generation energy-saving buildings.

9.
Appl Environ Microbiol ; 89(9): e0098323, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37655869

RESUMO

The asexual sporulation of filamentous fungi is an important mechanism for their reproduction, survival, and pathogenicity. In Aspergillus and several filamentous fungi, BrlA, AbaA, and WetA are the key elements of a central regulatory pathway controlling conidiation, and MedA is a developmental modifier that regulates temporal expression of central regulatory genes; however, their roles are largely unknown in nematode-trapping (NT) fungi. Arthrobotrys oligospora is a representative NT fungus, which can capture nematodes by producing adhesive networks (traps). Here, we characterized the function of AoMedA and three central developmental regulators (AoBrlA, AoAbaA, and AoWetA) in A. oligospora by gene disruption, phenotypic comparison, and multi-omics analyses, as these regulators are required for conidiation and play divergent roles in mycelial development, trap formation, lipid droplet accumulation, vacuole assembly, and secondary metabolism. A combined analysis of phenotypic traits and transcriptome showed that AoMedA and AoWetA are involved in the regulation of peroxisome, endocytosis, and autophagy. Moreover, yeast one-hybrid analysis showed that AoBrlA can regulate AoMedA, AoAbaA, and AoWetA, whereas AoMedA and AoAbaA can regulate AoWetA. Our results highlight the important roles of AoMedA, AoBrlA, AoAbaA, and AoWetA in conidiation, mycelia development, trap formation, and pathogenicity of A. oligospora and provide a basis for elucidating the relationship between conidiation and trap formation of NT fungi. IMPORTANCE Conidiation is the most common reproductive mode for many filamentous fungi and plays an essential role in the pathogenicity of fungal pathogens. Nematode-trapping (NT) fungi are a special group of filamentous fungi owing to their innate abilities to capture and digest nematodes by producing traps (trapping devices). Sporulation plays an important role in the growth and reproduction of NT fungi, and conidia are the basic components of biocontrol reagents for controlling diseases caused by plant-parasitic nematodes. Arthrobotrys oligospora is a well-known NT fungus and is a routinely used model fungus for probing the interaction between fungi and nematodes. In this study, the functions of four key regulators (AoMedA, AoBrlA, AoAbaA, and AoWetA) involved in conidiation were characterized in A. oligospora. A complex interaction between AoMedA and three central regulators was noted; these regulators are required for conidiation and trap formation and play a pleiotropic role in multiple intracellular activities. Our study first revealed the role of AoMedA and three central regulators in conidiation, trap formation, and pathogenicity of A. oligospora, which contributed to elucidating the regulatory mechanism of conidiation in NT fungi and helped in developing effective reagents for biocontrol of nematodes.


Assuntos
Ascomicetos , Nematoides , Animais , Metabolismo Secundário , Ascomicetos/fisiologia , Saccharomyces cerevisiae
10.
FASEB J ; 36(10): e22561, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36125044

RESUMO

Previous studies have found microRNA-1 (miR-1) and hyperpolarization-activated cyclic nucleotide-gated channel 2 (HCN2) may be involved in the pathogenesis of thyroid hormone (TH) induced cardiac hypertrophy. However, little is known about the role of miR-1 and HCN2 in thyroid stimulation hormone (TSH)-induced cardiac dysfunction. In order to investigate the molecular mechanisms of TSH induced cardiac dysfunction and the role of miR-1/HCN2 in that process, we evaluated the expression of miR-1a/HCN2 in the ventricular myocardium of hypothyroid mice and in TSH-stimulated H9c2 cardiomyocytes. Our data revealed that hypothyroidism mice had smaller hearts, ventricular muscle atrophy, and cardiac contractile dysfunction compared with euthyroid controls. The upregulation of miR-1a and downregulation of HCN2 were found in ventricular myocardium of hypothyroid mice and TSH-stimulated H9c2 cardiomyocytes, indicating that miR-1a and HCN2 may be involved in TSH-induced cardiac dysfunction. We also found that the regulation of miR-1a and HCN2 expression and HCN2 channel activity by TSH requires TSHR, while the regulation of HCN2 expression and HCN2 channel function by TSH requires miR-1a. Thus, our data revealed the potential mechanism of TSH-induced cardiac dysfunction and might shed new light on the pathological role of miR-1a/HCN2 in hypothyroid heart disease.


Assuntos
Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Hipotireoidismo , MicroRNAs , Canais de Potássio/metabolismo , Animais , Cardiomegalia/metabolismo , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/genética , Camundongos , MicroRNAs/genética , Hormônios Tireóideos , Tireotropina/metabolismo
11.
Anim Cogn ; 26(4): 1423-1430, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37231181

RESUMO

Birds have the ability to assess the risk of predation in their environment and adjust their antipredation strategies based on this risk information. However, whether nest site selection has effect on subsequent nest defence behaviour has not been studied. In this study, we aimed to determine whether the Japanese tit (Parus minor) exhibits a nest-box hole size preference and whether the entrance hole sizes of nest boxes influence the nest defence behaviour of tits. We hung nest boxes with three different entrance hole sizes (diameters: 6.5 cm, 4.5 cm and 2.8 cm) in our study sites and investigated which nest boxes were occupied by tits. In addition, by using dummy-presentation experiments, we observed the nest defence behaviours of tits that nested in boxes with 2.8 cm and 4.5 cm entrance holes towards common chipmunks (Tamias sibiricus, a small nest predator able to enter these holes) and Eurasian red squirrels (Sciurus vulgaris, a large nest predator unable to enter the 2.8 cm entrance hole). The tits that bred in nest boxes with 2.8 cm entrance holes exhibited more intense nest defence responses to chipmunks than to squirrels. In contrast, the tits that bred in nest boxes with 4.5 cm entrance holes exhibited similar nest defence responses to chipmunks and squirrels. Additionally, Japanese tits that bred in nest boxes with 2.8 cm entrance holes exhibited more intense behavioural responses to chipmunks than those that bred in nest boxes with 4.5 cm entrance holes. Our results suggested that Japanese tits prefer to occupy nest boxes with small holes for breeding and that nest-box characteristics influenced their nest defence behaviour.


Assuntos
Comportamento de Nidação , Passeriformes , Animais , Comportamento de Nidação/fisiologia , Passeriformes/fisiologia , Comportamento Predatório , Sciuridae , Japão
12.
Acta Pharmacol Sin ; 44(2): 446-453, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35896694

RESUMO

The current study evaluated the efficacy and safety of a denosumab biosimilar, QL1206 (60 mg), compared to placebo in postmenopausal Chinese women with osteoporosis and high fracture risk. At 31 study centers in China, a total of 455 postmenopausal women with osteoporosis and high fracture risk were randomly assigned to receive QL1206 (60 mg subcutaneously every 6 months) or placebo. From baseline to the 12-month follow-up, the participants who received QL1206 showed significantly increased bone mineral density (BMD) values (mean difference and 95% CI) in the lumbar spine: 4.780% (3.880%, 5.681%), total hip :3.930% (3.136%, 4.725%), femoral neck 2.733% (1.877%, 3.589%) and trochanter: 4.058% (2.791%, 5.325%) compared with the participants who received the placebo. In addition, QL1206 injection significantly decreased the serum levels of C-terminal crosslinked telopeptides of type 1 collagen (CTX): -77.352% (-87.080%, -66.844%), and N-terminal procollagen of type l collagen (P1NP): -50.867% (-57.184%, -45.217%) compared with the placebo over the period from baseline to 12 months. No new or unexpected adverse events were observed. We concluded that compared with placebo, QL1206 effectively increased the BMD of the lumbar spine, total hip, femoral neck and trochanter in postmenopausal Chinese women with osteoporosis and rapidly decreased bone turnover markers. This study demonstrated that QL1206 has beneficial effects on postmenopausal Chinese women with osteoporosis and high fracture risk.


Assuntos
Medicamentos Biossimilares , Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Osteoporose , Feminino , Humanos , Medicamentos Biossimilares/efeitos adversos , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea , Denosumab/uso terapêutico , Denosumab/farmacologia , Método Duplo-Cego , População do Leste Asiático , Osteoporose/tratamento farmacológico , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Pós-Menopausa
13.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688763

RESUMO

Enrofloxacin as a special fish medicine is widely used in aquaculture fishes in China. But the effect of enrofloxacin exposure to the gut of aquatic animals is still unclear. In our investigation, enrofloxacin (300 mg/kg feed) was experimentally exposed to the juvenile American shad for 7 days and monitored for alterations in metabolomic and transcriptomic responses. The results showed the similar subset of affected pathways (P-value < 0.05), but there were still many differences in the number of identified biomarkers (520 differentially expressed genes genes and 230 metabolites). Most gut metabolic profiles were related to oxidative stress, inflammation, and lipid metabolism. These multiomic results reveal the specific metabolic disruption by enrofloxacin altering many signaling pathways (P-value < 0.05), such as arginine and proline metabolism pathways, pyrimidine metabolism, the FoxO signaling pathway, and purine metabolism. In addition, the predicted functions of proteins analysis showed that enrofloxacin exposure in an aquaculture environment could prevent the occurrence of organic diseases, including Vibrio cholerae infection and bacterial toxins, in aquatic systems. This is the first research indicating that enrofloxacin affects the relationship between environmental microorganisms and intestinal metabolism, and a study of the ecotoxicity of enrofloxacin occurrences in the aquatic system is warranted.


Assuntos
Microbiota , Estresse Oxidativo , Animais , Enrofloxacina/farmacologia , Peixes , Metabolismo dos Lipídeos
14.
Medicina (Kaunas) ; 59(9)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37763718

RESUMO

Background and Objectives: Asymptomatic bacteriuria (ASB) is prevalent in kidney transplant recipients (KTRs) and is hypothesized to heighten the risk of subsequent urinary tract infections (UTIs). Whether antibiotic treatment of ASB in KTRs is beneficial has not been elucidated. Materials and Methods: We carried out a systematic review and meta-analysis of all randomized controlled trials (RCTs) and quasi-RCTs that examined the merits of managing asymptomatic bacteriuria in KTRs. The primary outcomes were rates of symptomatic urinary tract infections (UTIs) and antimicrobial resistance. Results: Five studies encompassing 566 patients were included. No significant difference in symptomatic UTI rates was found between antibiotics and no treatment groups (relative risk (RR) 1.05, 95% confidence interval (CI) = 0.78-1.41), with moderate heterogeneity (I2 = 36%). Antibiotic treatment was found to present an uncertain risk for the development of drug-resistant strains (RR = 1.51, 95% CI = 0.95-2.40, I2 = 0%). In all trials, no significant difference between study arms was demonstrated regarding patient and graft outcomes, such as graft function, graft loss, hospitalization due to UTI, all-cause mortality, or acute rejection. Conclusions: The practice of screening and treating kidney transplant patients for asymptomatic bacteriuria does not curtail the incidence of future symptomatic UTIs, increase antimicrobial resistance, or affect graft outcomes. Whether early treatment of ASB after kidney transplantation (<2 months) is beneficial requires more RCTs.


Assuntos
Bacteriúria , Transplante de Rim , Humanos , Bacteriúria/tratamento farmacológico , Transplante de Rim/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Antibacterianos/uso terapêutico , Hospitalização
15.
Environ Microbiol ; 24(12): 6524-6538, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36260054

RESUMO

The cyclic adenosine monophosphate-protein kinase A (cAMP-PKA) signalling pathway is evolutionarily conserved in eukaryotes and plays a crucial role in defending against external environmental challenges, which can modulate the cellular response to external stimuli. Arthrobotrys oligospora is a typical nematode-trapping fungus that specializes in adhesive networks to kill nematodes. To elucidate the biological roles of the cAMP-PKA signalling pathway, we characterized the orthologous adenylate cyclase AoAcy, a regulatory subunit (AoPkaR), and two catalytic subunits (AoPkaC1 and AoPkaC2) of PKA in A. oligospora by gene disruption, transcriptome, and metabolome analyses. Deletion of Aoacy significantly reduced the levels of cAMP and arthrobotrisins. Results revealed that Aoacy, AopkaR, and AopkaC1 were involved in hyphal growth, trap morphogenesis, sporulation, stress resistance, and autophagy. In addition, Aoacy and AopkaC1 were involved in the regulation of mitochondrial morphology, thereby affecting energy metabolism, whereas AopkaC2 affected sporulation, nuclei, and autophagy. Multi-omics results showed that the cAMP-PKA signalling pathway regulated multiple metabolic and cellular processes. Collectively, these data highlight the indispensable role of cAMP-PKA signalling pathway in the growth, development, and pathogenicity of A. oligospora, and provide insights into the regulatory mechanisms of signalling pathways in sporulation, trap formation, and lifestyle transition.


Assuntos
Ascomicetos , Nematoides , Animais , Ascomicetos/genética , Nematoides/microbiologia , AMP Cíclico/metabolismo , Morfogênese , Autofagia/genética
16.
Environ Microbiol ; 24(4): 1714-1730, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34431203

RESUMO

Resistance to inhibitors of cholinesterase 8 (Ric8) is a conserved guanine nucleotide exchange factor that is involved in the regulation of G-protein signalling in filamentous fungi. Here, we characterized an orthologous Ric8 (AoRic8) in Arthrobotrys oligospora by multi-omics analyses. The Aoric8 deletion (ΔAoric8) mutants lost an ability to produce traps essential for nematode predation, accompanied by a marked reduction in cAMP level. Yeast two-hybrid assay revealed that AoRic8 interacted with G-protein subunit Gα1. Moreover, the mutants were compromised in mycelia growth, conidiation, stress resistance, endocytosis, cellular components and intrahyphal hyphae. Revealed by transcriptomic analysis differentially upregulated genes in the absence of Aoric8 were involved in cell cycle, DNA replication and recombination during trap formation while downregulated genes were primarily involved in organelles, carbohydrate metabolism and amino acid metabolism. Metabolomic analysis showed that many compounds were markedly downregulated in ΔAoric8 mutants versus the wild-type strain. Our results demonstrated a crucial role for AoRic8 in the fungal growth, environmental adaption and nematode predation through control of cell cycle, organelle and secondary metabolism by G-protein signalling.


Assuntos
Ascomicetos , Nematoides , Animais , Ascomicetos/genética , Colinesterases/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Nematoides/genética , Nematoides/microbiologia
17.
PLoS Pathog ; 16(8): e1008766, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32857822

RESUMO

Pathogens commonly disrupt the intestinal epithelial barrier; however, how the epithelial immune system senses the loss of intestinal barrier as a danger signal to activate self-defense is unclear. Through an unbiased approach in the model nematode Caenorhabditis elegans, we found that the EGL-44/TEAD transcription factor and its transcriptional activator YAP-1/YAP (Yes-associated protein) were activated when the intestinal barrier was disrupted by infections with the pathogenic bacterium Pseudomonas aeruginosa PA14. Gene Ontology enrichment analysis of the genes containing the TEAD-binding sites revealed that "innate immune response" and "defense response to Gram-negative bacterium" were two top significantly overrepresented terms. Genetic inactivation of yap-1 and egl-44 significantly reduced the survival rate and promoted bacterial accumulation in worms after bacterial infections. Furthermore, we found that disturbance of the E-cadherin-based adherens junction triggered the nuclear translocation and activation of YAP-1/YAP in the gut of worms. Although YAP is a major downstream effector of the Hippo signaling, our study revealed that the activation of YAP-1/YAP was independent of the Hippo pathway during disruption of intestinal barrier. After screening 10 serine/threonine phosphatases, we identified that PP2A phosphatase was involved in the activation of YAP-1/YAP after intestinal barrier loss induced by bacterial infections. Additionally, our study demonstrated that the function of YAP was evolutionarily conserved in mice. Our study highlights how the intestinal epithelium recognizes the loss of the epithelial barrier as a danger signal to deploy defenses against pathogens, uncovering an immune surveillance program in the intestinal epithelium.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Permeabilidade da Membrana Celular , Células Epiteliais/imunologia , Microbioma Gastrointestinal/imunologia , Salmonelose Animal/imunologia , Salmonella typhimurium/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Camundongos , Salmonelose Animal/metabolismo , Salmonelose Animal/microbiologia , Salmonelose Animal/patologia , Transdução de Sinais , Proteínas de Sinalização YAP
18.
Langmuir ; 38(20): 6376-6386, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35561306

RESUMO

In recent years, adsorption-based membranes have been widely investigated to remove and separate textile pollutants. However, cyclic adsorption-desorption to reuse a single adsorbent and clear scientific evidence for the adsorption-desorption mechanism remains challenging. Herein, silk nanofibers were used to assess the adsorption potential for the typical anionic dyes from an aqueous medium, and they show great potential toward the removal of acid dyes from the aqueous solution with an adsorption rate of ∼98% in a 1 min interaction. Further, we measured the filtration proficiency of a silk nanofiber membrane in order to propose a continuous mechanism for the removal of acid blue dye, and a complete rejection was observed with a maximum permeability rate of ∼360 ± 5 L·m-2·h-1. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy studies demonstrate that this fast adsorption occurs due to multiple interactions between the dye molecule and the adsorbent substrate. The as-prepared material also shows remarkable results in desorption. A 50-time cycle exhibits complete adsorption and desorption ability, which not only facilitates high removal aptitude but also produces less solid waste than other conventional adsorbents. Additionally, fluorescent 2-bromo-2-methyl-propionic acid (abbreviated as EtOxPY)-silk nanofibers can facilitate to illustrate a clear adsorption and desorption mechanism. Therefore, the above-prescribed results make electrospun silk nanofibers a suitable choice for removing anionic dyes in real-time applications.


Assuntos
Corantes , Membranas Artificiais , Nanofibras , Seda , Descoloração da Água , Poluentes Químicos da Água , Ácidos/química , Adsorção , Ânions/química , Corantes/química , Filtração/instrumentação , Filtração/métodos , Concentração de Íons de Hidrogênio , Cinética , Nanofibras/química , Espectroscopia Fotoeletrônica , Seda/química , Espectroscopia de Infravermelho com Transformada de Fourier , Descoloração da Água/instrumentação , Descoloração da Água/métodos , Poluentes Químicos da Água/química
19.
Microb Ecol ; 83(4): 869-885, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34279697

RESUMO

The emergence and spread of azole resistance alleles in clinical and environmental isolates of Aspergillus fumigatus is a global human health concern and endangers the "One Health" approach in our fight against antifungal resistance (AFR) in this pathogen. A major challenge to combat AFR in A. fumigatus is the massive aerial dispersal ability of its asexual spores. Our recent fine-scale survey of greenhouse populations of A. fumigatus near Kunming, Yunnan, China, suggested that the use of azole fungicides for plant protection was likely a major driver of the high-frequency azole-resistant A. fumigatus (ARAF) in greenhouses. Here, we investigated the potential spread of those ARAF and the structure of geographic populations of A. fumigatus by analyzing 452 isolates from 19 geographic locations across Yunnan. We found lower frequencies of ARAF in these outdoor populations than those in greenhouses near Kunming, but there were abundant new alleles and new genotypes, including those associated with azole resistance, consistent with multiple independent origins of ARAF across Yunnan. Interestingly, among the four ecological niches, the sediments of a large lake near Kunming were found to have the highest frequency of ARAF (~ 43%). While most genetic variations were observed within the 19 local populations, statistically significant genetic differentiations were found between many subpopulations within Yunnan. Furthermore, similar to greenhouse populations, these outdoor populations of A. fumigatus in Yunnan were significantly different from those in other parts of the world. Our results call for increased attention to local and regional studies of this fungal pathogen to help develop targeted control strategies against ARAF.


Assuntos
Aspergillus fumigatus , Azóis , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Azóis/farmacologia , China , Variação Genética , Humanos
20.
J Appl Microbiol ; 132(3): 2144-2156, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34797022

RESUMO

AIMS: Phospholipase C (PLC) is a hydrolase involved in signal transduction in eukaryotic cells. This study aimed to understand the function of PLC in the nematode-trapping fungus Arthrobotrys oligospora. METHODS AND RESULTS: Orthologous PLC (AoPLC2) of A. oligospora was functionally analysed using gene disruption and multi-phenotypic analysis. Disrupting Aoplc2 caused a deformation of partial hyphal cells (about 10%) and conidia (about 50%), decreased the number of nuclei in both conidia and hyphal cells, and increased the accumulation of lipid droplets. Meanwhile, the sporulation-related genes fluG and abaA were downregulated in ΔAoplc2 mutants than in the wild-type strain. Moreover, ΔAoplc2 mutants were more sensitive to osmotic stressors. Importantly, the number of traps, electron-dense bodies in traps, and nematicidal activity of ΔAoplc2 mutants were reduced, and the shape of the traps was deformed. In addition, AoPLC2 was involved in the biosynthesis of secondary metabolites in A. oligospora. CONCLUSIONS: AoPLC2 plays an important role in the development of hyphae, spores, and cell nuclei, responses to stress, formation of traps, and predation of nematodes in A. oligospora. SIGNIFICANCE AND IMPACT OF STUDY: This study reveals the various functions of phospholipase C and elucidates the regulation of trap morphogenesis in nematode-trapping fungi.


Assuntos
Ascomicetos , Nematoides , Fosfolipases Tipo C , Animais , Ascomicetos/enzimologia , Ascomicetos/genética , Morfogênese , Nematoides/microbiologia , Fosfolipases Tipo C/genética , Fosfolipases Tipo C/metabolismo , Virulência/genética
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