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1.
bioRxiv ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39185155

RESUMEN

While increased mutation rates typically have negative consequences in multicellular organisms, hypermutation can be advantageous for microbes adapting to the environment. Previously, we identified two hypermutator Cryptococcus neoformans clinical isolates that rapidly develop drug resistance due to transposition of a retrotransposon, Cnl1. Cnl1-mediated hypermutation is caused by a nonsense mutation in the gene encoding a novel RNAi component, Znf3, combined with a tremendous transposon burden. To elucidate adaptative mechanisms following RNAi loss, two bioinformatic pipelines were developed to identify RNAi loss-of-function mutations in a collection of 387 sequenced C. neoformans isolates. Remarkably, several RNAi-loss isolates were identified that are not hypermutators and have not accumulated transposons. To test if these RNAi loss-of-function mutations can cause hypermutation, the mutations were introduced into a non-hypermutator strain with a high transposon burden, which resulted in a hypermutator phenotype. To further investigate if RNAi-loss isolates can become hypermutators, in vitro passaging was performed. Although no hypermutators were found in two C. neoformans RNAi-loss strains after short-term passage, hypermutation was observed in a passaged C. deneoformans strain with increased transposon burden. Additionally, when an RNAi-loss isolate was crossed with an isolate containing a high Cnl1 burden, F1 hypermutator progeny were identified with distinct mutational spectra. In addition to Cnl1 transpositions, insertions of a novel gigantic DNA transposon KDZ1 (~11 kb), contributed to hypermutation in the progeny. Our results suggest that RNAi loss is relatively common (7/387, ~1.8%) and enables distinct evolutionary trajectories: hypermutation following transposon accumulation or survival without hypermutation.

2.
Cell Rep ; 43(7): 114447, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38963761

RESUMEN

Obesity and type 2 diabetes cause a loss in brown adipose tissue (BAT) activity, but the molecular mechanisms that drive BAT cell remodeling remain largely unexplored. Using a multilayered approach, we comprehensively mapped a reorganization in BAT cells. We uncovered a subset of macrophages as lipid-associated macrophages (LAMs), which were massively increased in genetic and dietary model of BAT expansion. LAMs participate in this scenario by capturing extracellular vesicles carrying damaged lipids and mitochondria released from metabolically stressed brown adipocytes. CD36 scavenger receptor drove LAM phenotype, and CD36-deficient LAMs were able to increase brown fat genes in adipocytes. LAMs released transforming growth factor ß1 (TGF-ß1), which promoted the loss of brown adipocyte identity through aldehyde dehydrogenase 1 family member A1 (Aldh1a1) induction. These findings unfold cell dynamic changes in BAT during obesity and identify LAMs as key responders to tissue metabolic stress and drivers of loss of brown adipocyte identity.


Asunto(s)
Tejido Adiposo Pardo , Macrófagos , Obesidad , Animales , Obesidad/patología , Obesidad/metabolismo , Macrófagos/metabolismo , Tejido Adiposo Pardo/metabolismo , Ratones , Adipocitos Marrones/metabolismo , Ratones Endogámicos C57BL , Antígenos CD36/metabolismo , Antígenos CD36/genética , Factor de Crecimiento Transformador beta1/metabolismo , Masculino , Lípidos , Mitocondrias/metabolismo
3.
mBio ; 15(8): e0166124, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38980037

RESUMEN

Mucormycoses are emerging fungal infections caused by a variety of heterogeneous species within the Mucorales order. Among the Mucor species complex, Mucor circinelloides is the most frequently isolated pathogen in mucormycosis patients and despite its clinical significance, there is an absence of established genome manipulation techniques to conduct molecular pathogenesis studies. In this study, we generated a spontaneous uracil auxotrophic strain and developed a genetic transformation procedure to analyze molecular mechanisms conferring antifungal drug resistance. With this new model, phenotypic analyses of gene deletion mutants were conducted to define Erg3 and Erg6a as key biosynthetic enzymes in the M. circinelloides ergosterol pathway. Erg3 is a C-5 sterol desaturase involved in growth, sporulation, virulence, and azole susceptibility. In other fungal pathogens, erg3 mutations confer azole resistance because Erg3 catalyzes the production of a toxic diol upon azole exposure. Surprisingly, M. circinelloides produces only trace amounts of this toxic diol and yet, it is still susceptible to posaconazole and isavuconazole due to alterations in membrane sterol composition. These alterations are severely aggravated by erg3Δ mutations, resulting in ergosterol depletion and, consequently, hypersusceptibility to azoles. We also identified Erg6a as the main C-24 sterol methyltransferase, whose activity may be partially rescued by the paralogs Erg6b and Erg6c. Loss of Erg6a function diverts ergosterol synthesis to the production of cholesta-type sterols, resulting in resistance to amphotericin B. Our findings suggest that mutations or epimutations causing loss of Erg6 function may arise during human infections, resulting in antifungal drug resistance to first-line treatments against mucormycosis. IMPORTANCE: The Mucor species complex comprises a variety of opportunistic pathogens known to cause mucormycosis, a potentially lethal fungal infection with limited therapeutic options. The only effective first-line treatments against mucormycosis consist of liposomal formulations of amphotericin B and the triazoles posaconazole and isavuconazole, all of which target components within the ergosterol biosynthetic pathway. This study uncovered M. circinelloides Erg3 and Erg6a as key enzymes to produce ergosterol, a vital constituent of fungal membranes. Absence of any of those enzymes leads to decreased ergosterol and consequently, resistance to ergosterol-binding polyenes such as amphotericin B. Particularly, losing Erg6a function poses a higher threat as the ergosterol pathway is channeled into alternative sterols similar to cholesterol, which maintain membrane permeability. As a result, erg6a mutants survive within the host and disseminate the infection, indicating that Erg6a deficiency may arise during human infections and confer resistance to the most effective treatment against mucormycoses.


Asunto(s)
Antifúngicos , Vías Biosintéticas , Farmacorresistencia Fúngica , Ergosterol , Mucor , Ergosterol/biosíntesis , Ergosterol/metabolismo , Antifúngicos/farmacología , Farmacorresistencia Fúngica/genética , Vías Biosintéticas/genética , Humanos , Mucor/genética , Mucor/efectos de los fármacos , Mucor/metabolismo , Mucormicosis/microbiología , Mucormicosis/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Triazoles/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Eliminación de Gen , Nitrilos/farmacología , Piridinas/farmacología , Oxidorreductasas
4.
J Am Chem Soc ; 146(28): 19295-19302, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38943666

RESUMEN

Oxygen vacancies are generally considered to play a crucial role in the oxygen evolution reaction (OER). However, the generation of active sites created by oxygen vacancies is inevitably restricted by their condensation and elimination reactions. To overcome this limitation, here, we demonstrate a novel photoelectric reconstruction strategy to incorporate atomically dispersed Cu into ultrathin (about 2-3 molecular) amorphous oxyhydroxide (a-CuM, M = Co, Ni, Fe, or Zn), facilitating deprotonation of the reconstructed oxyhydroxide to generate high-valence Cu. The in situ XAFS results and first-principles calculations reveal that Cu atoms are stabilized at high valence during the OER process due to Jahn-Teller distortion, resulting in para-type double oxygen vacancies as dynamically stable catalytic sites. The optimal a-CuCo catalyst exhibits a record-high mass activity of 3404.7 A g-1 at an overpotential of 300 mV, superior to the benchmarking hydroxide and oxide catalysts. The developed photoelectric reconstruction strategy opens up a new pathway to construct in situ stable oxygen vacancies by high-valence Cu single sites, which extends the design rules for creating dynamically stable active sites.

5.
Sci Total Environ ; 945: 174121, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38901593

RESUMEN

The widespread use of surfactants raise challenges to biological wastewater treatment. Anaerobic ammonium oxidation (anammox) process has the potential to treat wastewater containing anionic surfactants, but the response of anammox consortia at the molecular level under long-term exposure is unclear. Using high-throughput sequencing and gene quantification, combined with molecular docking, the effect of sodium dodecyl sulfonate (SDS) on anammox consortia were investigated. Levels of reactive oxygen species (ROS) might be lower than the threshold of oxidative damage, while the increase of lactate dehydrogenase (LDH) represented the cell membrane damage. Decreased abundance of functional genes (hdh, hzsA and nirS) indicated the decrease of the anammox bacterial abundance. Trace amounts of N-acyl homoserine lactone (AHL, C6-HSL, C8-HSL and C12-HSL) contained in influent could induce endogenous quorum sensing (QS), which could regulate the correlation between functional bacteria to optimize the microbial community and strengthen the resistance of anammox consortia to SDS. In addition, the proliferation of disinfectant resistance genes might increase the environmental pathogenicity of sewage discharge. This work highlights the potential response mechanism of anammox consortium to surfactants and provides a universal microbial-friendly bioenhancement strategy based on QS.


Asunto(s)
Percepción de Quorum , Tensoactivos , Eliminación de Residuos Líquidos , Tensoactivos/metabolismo , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/microbiología , Oxidación-Reducción , Anaerobiosis , Compuestos de Amonio/metabolismo , Simulación del Acoplamiento Molecular , Consorcios Microbianos/fisiología
6.
J Am Chem Soc ; 146(19): 13527-13535, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38691638

RESUMEN

Closing the carbon and nitrogen cycles by electrochemical methods using renewable energy to convert abundant or harmful feedstocks into high-value C- or N-containing chemicals has the potential to transform the global energy landscape. However, efficient conversion avenues have to date been mostly realized for the independent reduction of CO2 or NO3-. The synthesis of more complex C-N compounds still suffers from low conversion efficiency due to the inability to find effective catalysts. To this end, here we present amorphous bismuth-tin oxide nanosheets, which effectively reduce the energy barrier of the catalytic reaction, facilitating efficient and highly selective urea production. With enhanced CO2 adsorption and activation on the catalyst, a C-N coupling pathway based on *CO2 rather than traditional *CO is realized. The optimized orbital symmetry of the C- (*CO2) and N-containing (*NO2) intermediates promotes a significant increase in the Faraday efficiency of urea production to an outstanding value of 78.36% at -0.4 V vs RHE. In parallel, the nitrogen and carbon selectivity for urea formation is also enhanced to 90.41% and 95.39%, respectively. The present results and insights provide a valuable reference for the further development of new catalysts for efficient synthesis of high-value C-N compounds from CO2.

7.
J Phys Chem A ; 128(17): 3273-3284, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38635947

RESUMEN

Herein, we report a computation study based on the density functional theory calculations to understand the mechanism and ligand effect of the base-stabilized dialumenes toward dihydrogen activation. Among all of the examined modes of dihydrogen activation using the base-stabilized dialumene, we found that the concerted 1,2-hydrogenation of the Al═Al double bond is kinetically more preferable. The concerted 1,2-hydrogenation of the Al═Al double bond adopts an electron-transfer model with certain asynchrony. That is, the initial electron donation from the H-H σ bonding orbital to the empty 3p orbital of the Al1 center is followed by the backdonation from the lone pair electron of the Al2 center to the H-H σ antibonding orbital. Combined with the energy decomposition analysis on the transition states of the concerted 1,2-hydrogenation of the Al═Al double bond and the topographic steric mapping analysis on the free dialumenes, we ascribe the higher reactivity of the aryl-substituted dialumene over the silyl-substituted analogue in dihydrogen activation to the stronger electron-withdrawing effect of the aryl group, which not only increases the flexibility of the Al═Al double bond but also enhances the Lewis acidity of the Al═Al core. Consequently, the aryl-substituted dialumene fragment suffers less geometric deformation, and the orbital interactions between the dialumene and dihydrogen moieties are more attractive during the 1,2-hydrogenation process. Moreover, our calculations also predict that the Al═Al double bond has a good tolerance with the stronger electron-withdrawing group (-CF3) and the weaker σ-donating N-heterocyclic carbene (NHC) analogue (e.g., triazol carbene and NHSi). The reactivity of the dialumene in dihydrogen activation can be further improved by introducing these groups as the supporting ligand and the stabilizing base on the Al═Al core, respectively.

8.
Phytomedicine ; 126: 155053, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38359483

RESUMEN

BACKGROUND: Cigarette smoke impairs mucociliary clearance via mechanisms such as inflammatory response and oxidative injury, which in turn induces various respiratory diseases. Naringenin, a naturally occurring flavonoid in grapes and grapefruit, has exhibited pharmacological properties such as anti-inflammatory, expectorant, and antioxidant properties. However, it is still unclear whether naringenin protects airway cilia from injury caused by cigarette smoke. PURPOSE: This study aimed to investigate the effect of naringenin on cigarette smoke extract (CSE)-induced structural and functional abnormalities in airway cilia and highlight the potential regulatory mechanism. METHODS: Initially, network pharmacology was used to predict the mechanism of action of naringenin in ciliary disease. Next, HE staining, immunofluorescence, TEM, qRT-PCR, western blot, and ELISA were performed to assess the effects of naringenin on airway cilia in tracheal rings and air-liquid interface (ALI) cultures of Sprague Dawley rats after co-exposure to CSE (10% or 20%) and naringenin (0, 25, 50, 100 µM) for 24 h. Finally, transcriptomics and molecular biotechnology methods were conducted to elucidate the mechanism by which naringenin protected cilia from CSE-induced damage in ALI cultures. RESULTS: The targets of ciliary diseases regulated by naringenin were significantly enriched in inflammation and oxidative stress pathways. Also, the CSE decreased the number of cilia in the tracheal rings and ALI cultures and reduced the ciliary beat frequency (CBF). However, naringenin prevented CSE-induced cilia damage via mechanisms such as the downregulation of cilia-related genes (e.g., RFX3, DNAI1, DNAH5, IFT88) and ciliary marker proteins such as DNAI2, FOXJ1, and ß-tubulin IV, the upregulation of inflammatory factors (e.g., IL-6, IL-8, IL-13), ROS and MDA. IL-17 signaling pathway might be involved in the protective effect of naringenin on airway cilia. Additionally, the cAMP signaling pathway might also be related to the enhancement of CBF by naringenin. CONCLUSION: In this study, we first found that naringenin reduces CSE-induced structural disruption of airway cilia in part via modulation of the IL-17 signaling pathway. Furthermore, we also found that naringenin enhances CBF by activating the cAMP signaling pathway. This is the first report to reveal the beneficial effects of naringenin on airway cilia and the potential underlying mechanisms.


Asunto(s)
Fumar Cigarrillos , Cilios , Flavanonas , Animales , Ratas , Ratas Sprague-Dawley , Cilios/metabolismo , Interleucina-17/metabolismo , Células Epiteliales
9.
Nat Commun ; 15(1): 1381, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360860

RESUMEN

Soft tissue sarcoma is a broad family of mesenchymal malignancies exhibiting remarkable histological diversity. We portray the proteomic landscape of 272 soft tissue sarcomas representing 12 major subtypes. Hierarchical classification finds the similarity of proteomic features between angiosarcoma and epithelial sarcoma, and elevated expression of SHC1 in AS and ES is correlated with poor prognosis. Moreover, proteomic clustering classifies patients of soft tissue sarcoma into 3 proteomic clusters with diverse driven pathways and clinical outcomes. In the proteomic cluster featured with the high cell proliferation rate, APEX1 and NPM1 are found to promote cell proliferation and drive the progression of cancer cells. The classification based on immune signatures defines three immune subtypes with distinctive tumor microenvironments. Further analysis illustrates the potential association between immune evasion markers (PD-L1 and CD80) and tumor metastasis in soft tissue sarcoma. Overall, this analysis uncovers sarcoma-type-specific changes in proteins, providing insights about relationships of soft tissue sarcoma.


Asunto(s)
Hemangiosarcoma , Sarcoma , Neoplasias de los Tejidos Blandos , Humanos , Proteómica , Sarcoma/metabolismo , Biomarcadores , Análisis por Conglomerados , Neoplasias de los Tejidos Blandos/genética , Neoplasias de los Tejidos Blandos/patología , Microambiente Tumoral
10.
ACS Chem Biol ; 19(3): 592-598, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38380973

RESUMEN

As ligand-gated ion channels, nicotinic acetylcholine receptors (nAChRs) are widely distributed in the central and peripheral nervous systems and are associated with the pathogenesis of various degenerative neurological diseases. Here, we report the results of phage display-based de novo screening of an 11-residue linear peptide (named LKP1794) that targets the α7 nAChR, which is among the most abundant nAChR subtypes in the brain. Moreover, two d-peptides were generated through mirror image and/or primary sequence inverso isomerization (termed DRKP1794 and DKP1794) and displayed improved inhibitory effects (IC50 = 0.86 and 0.35 µM, respectively) on α7 nAChR compared with the parent l-peptide LKP1794 (IC50 = 2.48 µM), which markedly enhanced serum stability. A peptide-based fluorescence probe was developed using proteolytically resistant DKP1794 to specifically image the α7 nAChR in living cells. This work provides a new peptide tool to achieve inhibitory modulation and specifically image the α7 nAChR.


Asunto(s)
Receptores Nicotínicos , Receptor Nicotínico de Acetilcolina alfa 7 , Receptor Nicotínico de Acetilcolina alfa 7/química , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Isomerismo , Receptores Nicotínicos/metabolismo , Péptidos/farmacología , Péptidos/química , Encéfalo/metabolismo
11.
Phytomedicine ; 124: 155256, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38181527

RESUMEN

BACKGROUND: Alveolar macrophages are one of the momentous regulators in pulmonary inflammatory responses, which can secrete extracellular vesicles (EVs) packing miRNAs. Ferroptosis, an iron-dependent cell death, is associated with cigarette smoke-induced lung injury, and EVs have been reported to regulate ferroptosis by transporting intracellular iron. However, the regulatory mechanism of alveolar macrophage-derived EVs has not been clearly illuminated in smoking-related pulmonary ferroptosis. Despite the known anti-ferroptosis effects of naringenin in lung injury, whether naringenin controls EVs-mediated ferroptosis has not yet been explored. PURPOSE: We explore the effects of EVs from cigarette smoke-stimulated alveolar macrophages in lung epithelial ferroptosis, and elucidate the EV miRNA-mediated pharmacological mechanism of naringenin. STUDY DESIGN AND METHODS: Differential and ultracentrifugation were conducted to extract EVs from different alveolar macrophages treatment groups in vitro. Both intratracheal instilled mice and treated epithelial cells were used to investigate the roles of EVs from alveolar macrophages involved in ferroptosis. Small RNA sequencing analysis was performed to distinguish altered miRNAs in EVs. The ferroptotic effects of EV miRNAs were examined by applying dual-Luciferase reporter assay and miRNA inhibitor transfection experiment. RESULTS: Here, we firstly reported that EVs from cigarette smoke extract-induced alveolar macrophages (CSE-EVs) provoked pulmonary epithelial ferroptosis. The ferroptosis inhibitor ferrostatin-1 treatment reversed these changes in vitro. Moreover, EVs from naringenin and CSE co-treated alveolar macrophages (CSE+Naringenin-EVs) markedly attenuated the lung epithelial ferroptosis compared with CSE-EVs. Notably, we identified miR-23a-3p as the most dramatically changed miRNA among Normal-EVs, CSE-EVs, and CSE+Naringenin-EVs. Further experimental investigation showed that ACSL4, a pro-ferroptotic gene leading to lipid peroxidation, was negatively regulated by miR-23a-3p. The inhibition of miR-23a-3p diminished the efficacy of CSE+Naringenin-EVs. CONCLUSION: Our findings firstly provided evidence that naringenin elevated the EV miR-23a-3p level from CSE-induced alveolar macrophages, thereby inhibiting the mouse lung epithelial ferroptosis via targeting ACSL4, and further complemented the mechanism of cigarette-induced lung injury and the protection of naringenin in a paracrine manner. The administration of miR-23a-3p-enriched EVs has the potential to ameliorate pulmonary ferroptosis.


Asunto(s)
Fumar Cigarrillos , Vesículas Extracelulares , Ferroptosis , Flavanonas , Lesión Pulmonar , MicroARNs , Ratones , Animales , Macrófagos Alveolares/metabolismo , Fumar Cigarrillos/efectos adversos , Pulmón/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Vesículas Extracelulares/metabolismo , Hierro/metabolismo
12.
Cancer Discov ; 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38241033

RESUMEN

The limited efficacy of currently approved immunotherapies in EGFR-driven lung adenocarcinoma (LUAD) underscores the need to better understand alternative mechanisms governing local immunosuppression to fuel novel therapies. Elevated surfactant and GM-CSF secretion from the transformed epithelium induces tumor-associated alveolar macrophage (TA-AM) proliferation which supports tumor growth by rewiring inflammatory functions and lipid metabolism. TA-AM properties are driven by increased GM-CSF-PPARγ signaling and inhibition of airway GM-CSF or PPARγ in TA-AMs suppresses cholesterol efflux to tumor cells, which impairs EGFR phosphorylation and restrains LUAD progression. In the absence of TA-AM metabolic support, LUAD cells compensate by increasing cholesterol synthesis, and blocking PPARγ in TA-AMs simultaneous with statin therapy further suppresses tumor progression and increases proinflammatory immune responses. These results reveal new therapeutic combinations for immunotherapy resistant EGFR-mutant LUADs and demonstrate how cancer cells can metabolically co-opt TA-AMs through GM-CSF-PPARγ signaling to provide nutrients that promote oncogenic signaling and growth.

13.
Cancer Discov ; : OF1-OF22, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38270272

RESUMEN

The limited efficacy of currently approved immunotherapies in EGFR-driven lung adenocarcinoma (LUAD) underscores the need to better understand alternative mechanisms governing local immunosuppression to fuel novel therapies. Elevated surfactant and GM-CSF secretion from the transformed epithelium induces tumor-associated alveolar macrophage (TA-AM) proliferation, which supports tumor growth by rewiring inflammatory functions and lipid metabolism. TA-AM properties are driven by increased GM-CSF-PPARγ signaling and inhibition of airway GM-CSF or PPARγ in TA-AMs suppresses cholesterol efflux to tumor cells, which impairs EGFR phosphorylation and restrains LUAD progression. In the absence of TA-AM metabolic support, LUAD cells compensate by increasing cholesterol synthesis, and blocking PPARγ in TA-AMs simultaneous with statin therapy further suppresses tumor progression and increases proinflammatory immune responses. These results reveal new therapeutic combinations for immunotherapy-resistant EGFR-mutant LUADs and demonstrate how cancer cells can metabolically co-opt TA-AMs through GM-CSF-PPARγ signaling to provide nutrients that promote oncogenic signaling and growth. SIGNIFICANCE: Alternate strategies harnessing anticancer innate immunity are required for lung cancers with poor response rates to T cell-based immunotherapies. This study identifies a targetable, mutually supportive, metabolic relationship between macrophages and transformed epithelium, which is exploited by tumors to obtain metabolic and immunologic support to sustain proliferation and oncogenic signaling.

14.
Sci Total Environ ; 914: 169958, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38211863

RESUMEN

Aquaculture wastewater, rich in organic nutrients, is an essential environmental factor. When applied to seaweed cultivation systems, this wastewater holds the potential to notably increase the growth rate and carbon capture of Sarcodia suae. Sarcodia suae has the potential to be a healthy food due to its various biological activities; however, its chemical composition has yet to be completely defined. In this study, we applied a UHPLC-HRMS-based foodomics strategy to determine and classify possible bioactive metabolites in S. suae. From pooled seaweed samples (S. suae cultured in filtered running, FR, aquaponic recirculation, AR systems), we identified 179 and 146 compounds in POS and NEG modes, respectively. These compounds were then classified based on their structures using the Classyfire classification. Results show that S. suae in AR exhibited higher growth performance, and ten upregulated metabolites were determined. We also validated the anti-inflammatory and antioxidative bioactivities of some selected compounds. Our study provided important insights into the potential use of fish wastewater in aquaponic systems to profile and produce bioactive compounds in S. suae comprehensively. This has significant implications for the development of sustainable food and the promotion of environmental health.


Asunto(s)
Algas Marinas , Aguas Residuales , Animales , Antioxidantes , Peces , Acuicultura/métodos , Verduras , Antiinflamatorios , Cromatografía Líquida de Alta Presión
15.
Nat Commun ; 14(1): 8252, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38086788

RESUMEN

Telomeres are nucleoprotein structures at the ends of linear chromosomes. In humans, they consist of TTAGGG repeats, which are bound by dedicated proteins such as the shelterin complex. This complex blocks unwanted DNA damage repair at telomeres, e.g. by suppressing nonhomologous end joining (NHEJ) through its subunit TRF2. Here, we describe ZNF524, a zinc finger protein that directly binds telomeric repeats with nanomolar affinity, and reveal base-specific sequence recognition by cocrystallization with telomeric DNA. ZNF524 localizes to telomeres and specifically maintains the presence of the TRF2/RAP1 subcomplex at telomeres without affecting other shelterin members. Loss of ZNF524 concomitantly results in an increase in DNA damage signaling and recombination events. Overall, ZNF524 is a direct telomere-binding protein involved in the maintenance of telomere integrity.


Asunto(s)
Telómero , Proteína 2 de Unión a Repeticiones Teloméricas , Humanos , Proteína 2 de Unión a Repeticiones Teloméricas/genética , Telómero/genética , Telómero/metabolismo , Complejo Shelterina , Proteínas de Unión a Telómeros/metabolismo , ADN/genética , ADN/metabolismo
16.
Front Immunol ; 14: 1298186, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38155971

RESUMEN

For decades, the therapeutic goal of conventional treatment among inflammatory bowel disease (IBD) patients is alleviating exacerbations in acute phase, maintaining remission, reducing recurrence, preventing complications, and increasing quality of life. However, the persistent mucosal/submucosal inflammation tends to cause irreversible changes in the intestinal structure, which can barely be redressed by conventional treatment. In the late 1990s, monoclonal biologics, mainly anti-TNF (tumor necrosis factor) drugs, were proven significantly helpful in inhibiting mucosal inflammation and improving prognosis in clinical trials. Meanwhile, mucosal healing (MH), as a key endoscopic and histological measurement closely associated with the severity of symptoms, has been proposed as primary outcome measures. With deeper comprehension of the mucosal microenvironment, stem cell niche, and underlying mucosal repair mechanisms, diverse potential strategies apart from monoclonal antibodies have been arising or undergoing clinical trials. Herein, we elucidate key steps or targets during the course of MH and review some promising treatment strategies capable of promoting MH in IBD.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Calidad de Vida , Humanos , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Mucosa Intestinal/patología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/diagnóstico , Inflamación/patología
17.
Front Plant Sci ; 14: 1236145, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37908827

RESUMEN

Ephedra is an important plant in Chinese medicine; however, there are few reports on two species of Ephedra which are distributed at high altitudes from 3000 to 5200 meters. We collected a total of 84 individuals representing five Ephedra gerardiana and nine Ephedra saxatilis populations respectively located from 3158 to 5200 meters altitude, and determined the relative content of 213 metabolites using UHPLC-MS/MS (Ultra-High-Performance Liquid Chromatography-tandem mass spectrometry). 37 Chemical compositions were annotated using the KEGG (Kyoto Encyclopaedia of Genes and Genomes) database. From the top five significant enrichments in metabolic KEGG pathway analysis, we found a total of 166 compounds belonging to phenylpropanoids, 123 flavonoids, 67 metabolites carried by ABC transporters, and 61 in purine metabolism. We identified the top 8 altitude-related compounds in two species. Ephedrine and pseudoephedrine were found to be associated with altitude in both E. saxatilis and E. gerardiana. To verify which environmental factors influenced the metabolic content, the soil moisture and temperature of each population site were collected, and quantitative analysis of ephedrine and pseudoephedrine was performed using UHPLC-MS (Ultra-High-Performance liquid chromatography-tandem mass spectrometry). After detection, soil moisture ranged from 0.074 to 0.177 mm3/mm3, and temperature ranged from 9.7°C to 23.9°C. The content of ephedrine ranged from (0.84 ± 0.49)% to (2.01 ± 0.41)% in E. saxatilis, which was positively correlated with soil moisture; the content of pseudoephedrine ranged from (0.72 ± 0.45)% to (1.11 ± 0.57)% and was negatively correlated with soil moisture. In contrast to these results, in E. gerardiana, the content of ephedrine and pseudoephedrine was negatively correlated with soil moisture. Furthermore, the trends of alkaloid contents in two kinds of Ephedra were similar when the temperature was lower than 17°C even if the sum was various. With the increase in soil moisture and temperature, the total alkaloid content of E. saxatilis was higher than that of E. gerardiana. When the soil moisture was lower, the alkaloid content of the two Ephedra species was higher. These results provide useful data for the future separation of new compounds, and for seed homogeneous growth to determine artificial breeding of Ephedra located at high altitudes.

18.
JACS Au ; 3(10): 2660-2676, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37885575

RESUMEN

There is ever-growing research interest in nanomaterials because of the unique properties that emerge on the nanometer scale. While crystalline nanomaterials have received a surge of attention for exhibiting state-of-the-art properties in various fields, their amorphous counterparts have also attracted attention in recent years owing to their unique structural features that crystalline materials lack. In short, amorphous nanomaterials only have short-range order at the atomic scale, and their atomic packing lacks long-range periodic arrangement, in which the coordinatively unsaturated environment, isotropic atomic structure, and modulated electron state all contribute to their outstanding performance in various applications. Given their intriguing characteristics, we herein present a series of representative works to elaborate on the structural advantages of amorphous nanomaterials as well as their enhanced electrocatalytic, surface-enhanced Raman scattering (SERS), and mechanical properties, thereby elucidating the underlying structure-function relationship. We hope that this proposed relationship will be universally applicable, thus encouraging future work in the design of amorphous materials that show promising performance in a wide range of fields.

19.
Neuroimage ; 281: 120374, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37729795

RESUMEN

The study of neural circuits, which underlies perception, cognition, emotion, and behavior, is essential for understanding the mammalian brain, a complex organ consisting of billions of neurons. To study the structure and function of the brain, in vivo neuronal labeling and imaging techniques are crucial as they provide true physiological information that ex vivo methods cannot offer. In this paper, we present a new strategy for in vivo neuronal labeling and quantification using MRI. We demonstrate the efficacy of this method by delivering the oatp1a1 gene to the target neurons using rAAV2-retro virus. OATP1A1 protein expression on the neuronal membrane increased the uptake of a specific MRI contrast agent (Gd-EOB-DTPA), leading to hyperintense signals on T1W images of labeled neuronal populations. We also used dynamic contrast enhancement-based methods to obtain quantitative information on labeled neuronal populations in vivo.

20.
Immunity ; 56(9): 2086-2104.e8, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37572655

RESUMEN

The limited efficacy of immunotherapies against glioblastoma underscores the urgency of better understanding immunity in the central nervous system. We found that treatment with αCTLA-4, but not αPD-1, prolonged survival in a mouse model of mesenchymal-like glioblastoma. This effect was lost upon the depletion of CD4+ T cells but not CD8+ T cells. αCTLA-4 treatment increased frequencies of intratumoral IFNγ-producing CD4+ T cells, and IFNγ blockade negated the therapeutic impact of αCTLA-4. The anti-tumor activity of CD4+ T cells did not require tumor-intrinsic MHC-II expression but rather required conventional dendritic cells as well as MHC-II expression on microglia. CD4+ T cells interacted directly with microglia, promoting IFNγ-dependent microglia activation and phagocytosis via the AXL/MER tyrosine kinase receptors, which were necessary for tumor suppression. Thus, αCTLA-4 blockade in mesenchymal-like glioblastoma promotes a CD4+ T cell-microglia circuit wherein IFNγ triggers microglia activation and phagocytosis and microglia in turn act as antigen-presenting cells fueling the CD4+ T cell response.


Asunto(s)
Glioblastoma , Ratones , Animales , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Antígeno CTLA-4 , Células TH1 , Microglía , Linfocitos T CD8-positivos , Fagocitosis , Células Dendríticas , Linfocitos T CD4-Positivos
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