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1.
Mol Cell ; 81(16): 3294-3309.e12, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34293321

RESUMO

Temperature is a variable component of the environment, and all organisms must deal with or adapt to temperature change. Acute temperature change activates cellular stress responses, resulting in refolding or removal of damaged proteins. However, how organisms adapt to long-term temperature change remains largely unexplored. Here we report that budding yeast responds to long-term high temperature challenge by switching from chaperone induction to reduction of temperature-sensitive proteins and re-localizing a portion of its proteome. Surprisingly, we also find that many proteins adopt an alternative conformation. Using Fet3p as an example, we find that the temperature-dependent conformational difference is accompanied by distinct thermostability, subcellular localization, and, importantly, cellular functions. We postulate that, in addition to the known mechanisms of adaptation, conformational plasticity allows some polypeptides to acquire new biophysical properties and functions when environmental change endures.


Assuntos
Adaptação Fisiológica/genética , Proteoma/genética , Estresse Fisiológico/genética , Transcriptoma/genética , Aclimatação/genética , Animais , Exposição Ambiental/efeitos adversos , Regulação Fúngica da Expressão Gênica/genética , Temperatura Alta/efeitos adversos , Saccharomycetales/genética
2.
Mol Cell ; 81(12): 2656-2668.e8, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33930332

RESUMO

A deficient interferon (IFN) response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been implicated as a determinant of severe coronavirus disease 2019 (COVID-19). To identify the molecular effectors that govern IFN control of SARS-CoV-2 infection, we conducted a large-scale gain-of-function analysis that evaluated the impact of human IFN-stimulated genes (ISGs) on viral replication. A limited subset of ISGs were found to control viral infection, including endosomal factors inhibiting viral entry, RNA binding proteins suppressing viral RNA synthesis, and a highly enriched cluster of endoplasmic reticulum (ER)/Golgi-resident ISGs inhibiting viral assembly/egress. These included broad-acting antiviral ISGs and eight ISGs that specifically inhibited SARS-CoV-2 and SARS-CoV-1 replication. Among the broad-acting ISGs was BST2/tetherin, which impeded viral release and is antagonized by SARS-CoV-2 Orf7a protein. Overall, these data illuminate a set of ISGs that underlie innate immune control of SARS-CoV-2/SARS-CoV-1 infection, which will facilitate the understanding of host determinants that impact disease severity and offer potential therapeutic strategies for COVID-19.


Assuntos
Antígenos CD/genética , Interações Hospedeiro-Patógeno/genética , Fatores Reguladores de Interferon/genética , Interferon Tipo I/genética , SARS-CoV-2/genética , Proteínas Virais/genética , Animais , Antígenos CD/química , Antígenos CD/imunologia , Sítios de Ligação , Linhagem Celular Tumoral , Chlorocebus aethiops , Retículo Endoplasmático/genética , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/virologia , Proteínas Ligadas por GPI/química , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Regulação da Expressão Gênica , Complexo de Golgi/genética , Complexo de Golgi/imunologia , Complexo de Golgi/virologia , Células HEK293 , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Fatores Reguladores de Interferon/classificação , Fatores Reguladores de Interferon/imunologia , Interferon Tipo I/imunologia , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , SARS-CoV-2/imunologia , Transdução de Sinais , Células Vero , Proteínas Virais/química , Proteínas Virais/imunologia , Internalização do Vírus , Liberação de Vírus/genética , Liberação de Vírus/imunologia , Replicação Viral/genética , Replicação Viral/imunologia
3.
Nature ; 600(7889): 536-542, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34819669

RESUMO

The cell is a multi-scale structure with modular organization across at least four orders of magnitude1. Two central approaches for mapping this structure-protein fluorescent imaging and protein biophysical association-each generate extensive datasets, but of distinct qualities and resolutions that are typically treated separately2,3. Here we integrate immunofluorescence images in the Human Protein Atlas4 with affinity purifications in BioPlex5 to create a unified hierarchical map of human cell architecture. Integration is achieved by configuring each approach as a general measure of protein distance, then calibrating the two measures using machine learning. The map, known as the multi-scale integrated cell (MuSIC 1.0), resolves 69 subcellular systems, of which approximately half are to our knowledge undocumented. Accordingly, we perform 134 additional affinity purifications and validate subunit associations for the majority of systems. The map reveals a pre-ribosomal RNA processing assembly and accessory factors, which we show govern rRNA maturation, and functional roles for SRRM1 and FAM120C in chromatin and RPS3A in splicing. By integration across scales, MuSIC increases the resolution of imaging while giving protein interactions a spatial dimension, paving the way to incorporate diverse types of data in proteome-wide cell maps.


Assuntos
Cromossomos , Proteoma , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Cromatina/genética , Cromossomos/metabolismo , Humanos , Proteínas Associadas à Matriz Nuclear/metabolismo , Proteoma/metabolismo , RNA Ribossômico , Proteínas de Ligação a RNA/genética
4.
PLoS Biol ; 21(8): e3002247, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37590302

RESUMO

Mitochondria are in a constant balance of fusion and fission. Excessive fission or deficient fusion leads to mitochondrial fragmentation, causing mitochondrial dysfunction and physiological disorders. How the cell prevents excessive fission of mitochondria is not well understood. Here, we report that the fission yeast AAA-ATPase Yta4, which is the homolog of budding yeast Msp1 responsible for clearing mistargeted tail-anchored (TA) proteins on mitochondria, plays a critical role in preventing excessive mitochondrial fission. The absence of Yta4 leads to mild mitochondrial fragmentation in a Dnm1-dependent manner but severe mitochondrial fragmentation upon induction of mitochondrial depolarization. Overexpression of Yta4 delocalizes the receptor proteins of Dnm1, i.e., Fis1 (a TA protein) and Mdv1 (the bridging protein between Fis1 and Dnm1), from mitochondria and reduces the localization of Dnm1 to mitochondria. The effect of Yta4 overexpression on Fis1 and Mdv1, but not Dnm1, depends on the ATPase and translocase activities of Yta4. Moreover, Yta4 interacts with Dnm1, Mdv1, and Fis1. In addition, Yta4 competes with Dnm1 for binding Mdv1 and decreases the affinity of Dnm1 for GTP and inhibits Dnm1 assembly in vitro. These findings suggest a model, in which Yta4 inhibits mitochondrial fission by inhibiting the function of the mitochondrial divisome composed of Fis1, Mdv1, and Dnm1. Therefore, the present work reveals an uncharacterized molecular mechanism underlying the inhibition of mitochondrial fission.


Assuntos
Demência Frontotemporal , Schizosaccharomyces , Humanos , ATPases Associadas a Diversas Atividades Celulares/genética , Dinâmica Mitocondrial , Adenosina Trifosfatases , Mitocôndrias , Schizosaccharomyces/genética
5.
Cell ; 147(5): 1159-70, 2011 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-22100643

RESUMO

Entorhinal grid cells have periodic, hexagonally patterned firing locations that scale up progressively along the dorsal-ventral axis of medial entorhinal cortex. This topographic expansion corresponds with parallel changes in cellular properties dependent on the hyperpolarization-activated cation current (Ih), which is conducted by hyperpolarization-activated cyclic nucleotide-gated (HCN) channels. To test the hypothesis that grid scale is determined by Ih, we recorded grid cells in mice with forebrain-specific knockout of HCN1. We find that, although the dorsal-ventral gradient of the grid pattern was preserved in HCN1 knockout mice, the size and spacing of the grid fields, as well as the period of the accompanying theta modulation, was expanded at all dorsal-ventral levels. There was no change in theta modulation of simultaneously recorded entorhinal interneurons. These observations raise the possibility that, during self-motion-based navigation, Ih contributes to the gain of the transformation from movement signals to spatial firing fields.


Assuntos
Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Córtex Entorrinal/citologia , Córtex Entorrinal/fisiologia , Canais de Potássio/metabolismo , Animais , Mapeamento Encefálico , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Interneurônios , Masculino , Camundongos , Camundongos Knockout , Canais de Potássio/genética
6.
J Biol Chem ; 300(3): 105754, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38360270

RESUMO

KDELR (Erd2 [ER retention defective 2] in yeasts) is a receptor protein that retrieves endoplasmic reticulum (ER)-resident proteins from the Golgi apparatus. However, the role of the KDELR-mediated ER-retrieval system in regulating cellular homeostasis remains elusive. Here, we show that the absence of Erd2 triggers the unfolded protein response (UPR) and enhances mitochondrial respiration and reactive oxygen species in an UPR-dependent manner in the fission yeast Schizosaccharomyces pombe. Moreover, we perform transcriptomic analysis and find that the expression of genes related to mitochondrial respiration and the tricarboxylic acid cycle is upregulated in a UPR-dependent manner in cells lacking Erd2. The increased mitochondrial respiration and reactive oxygen species production is required for cell survival in the absence of Erd2. Therefore, our findings reveal a novel role of the KDELR-Erd2-mediated ER-retrieval system in modulating mitochondrial functions and highlight its importance for cellular homeostasis in the fission yeast.


Assuntos
Retículo Endoplasmático , Mitocôndrias , Schizosaccharomyces , Resposta a Proteínas não Dobradas , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Mitocôndrias/genética , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo
7.
Small ; : e2405164, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39180458

RESUMO

Photodynamic therapy (PDT) is a promising cancer treatment, but limited oxygen supply in tumors (hypoxia) can hinder its effectiveness. This is because traditional PDT relies on Type-II reactions that require oxygen. Type-I photosensitizers (PSs) offer a promising approach to overcome the limitations of tumor photodynamic therapy (PDT) in hypoxic environments. To leverage the advantages of Type-I PDT, the design and evaluation of a series of Type-I PSs for developing pure Type-1 PSs, by incorporating benzene, thiophene, or bithiophene into the donor-acceptor molecular skeleton are reported. Among them, CTTI (with bithiophene) shows the best performance, generating the most superoxide radical (O2 •-) upon light irradiation. Importantly, CTTI exclusively produced superoxide radicals, avoiding the less effective Type-II pathway. This efficiency is due to CTTI's energy gap and low reduction potential, which favor electron transfer to oxygen for O2 •- generation. Finally, CTTI NPs are successfully fabricated by encapsulating CTTI into liposomes, and validated to be effective in killing tumor cells, even under hypoxic conditions, making them promising hypoxia-tolerant tumor phototheranostic agents in both in vitro and in vivo applications.

8.
Cell Biol Toxicol ; 40(1): 86, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39382800

RESUMO

BACKGROUND: Renal interstitial fibrosis (RIF) is a common feature of chronic kidney diseases (CKD), with epithelial-mesenchymal transition (EMT) being one of its important mechanisms. S100A2 is a protein associated with cell proliferation and differentiation, but its specific functions and molecular mechanisms in RIF remain to be determined. METHODS: S100A2 levels were evaluated in three mouse models, including unilateral ureteral obstruction (UUO), ischemia-reperfusion injury (IRI), and aristolochic acid nephropathy (AAN), as well as in TGF-ß1- treated HK-2 cells and in kidney tissue samples. Furthermore, the role of S100A2 and its interaction with FoxO1 was investigated using RT-qPCR, immunoblotting, immunofluorescence staining, co-immunoprecipitation (Co-IP), transcriptome sequencing, and gain- or loss-of-function approaches in vitro. RESULTS: Elevated expression levels of S100A2 were observed in three mouse models and TGF-ß1-treated HK2 cells, as well as in kidney tissue samples. Following siRNA silencing of S100A2, exposure to TGF-ß1 in cultured HK-2 cells suppressed EMT process and extracellular matrix (ECM) accumulation. Conversely, Overexpression of S100A2 induced EMT and ECM deposition. Notably, we identified that S100A2-mediated EMT depends on FoxO1. Immunofluorescence staining indicated that S100A2 and FoxO1 colocalized in the nucleus and cytoplasm, and their interaction was verified in Co-IP assay. S100A2 knockdown decreased TGF-ß1-induced phosphorylation of FoxO1 and increased its protein expression, whereas S100A2 overexpression hampered FoxO1 activation. Furthermore, pharmacological blockade of FoxO1 rescued the induction of TGF-ß1 on EMT and ECM deposition in S100A2 siRNA-treated cells. CONCLUSION: S100A2 activation exacerbates interstitial fibrosis in kidneys by facilitating FoxO1-mediated EMT.


Assuntos
Transição Epitelial-Mesenquimal , Proteína Forkhead Box O1 , Rim , Proteínas S100 , Fator de Crescimento Transformador beta1 , Animais , Humanos , Masculino , Camundongos , Linhagem Celular , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Fibrose , Proteína Forkhead Box O1/metabolismo , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Nefropatias/induzido quimicamente , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Proteínas S100/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia , Obstrução Ureteral/complicações
9.
Phys Chem Chem Phys ; 26(33): 22220-22229, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39129471

RESUMO

In this study, we explore the mass transfer and separation mechanism of Li+ and Mg2+ confined within the flexible nanoporous zeolite imidazolate framework ZIF-8 under the influence of an electric field, employing molecular dynamics simulation. Our results highlight that the electric field accelerates the dehydration process of ions and underscore the critical importance of ZIF-8 framework flexibility in determining the separation selectivity of the ZIF-8 membrane. The electric field is shown to diminish ion hydration in the confined space of ZIF-8, notably disrupting the orientation of water molecules in the first hydration shells of ions, leading to an asymmetrical ionic hydration structure characterized by the uniform alignment of water dipoles. Furthermore, despite the geometrical constraints imposed by the ZIF-8 framework, the electric field significantly enhances ionic mobility. Notably, the less stable hydration shell of Li+ facilitates its rapid, dehydration-induced transit through ZIF-8 nanopores, unlike Mg2+, whose stable hydration shell impedes dehydration. Further investigation into the structural characteristics of the six-ring windows traversed by Li+ and Mg2+ ions reveals distinct mechanisms of passage: for Mg2+ ions, significant window expansion is necessary, while for Li+ ions, the mechanism involves both window expansion and partial dehydration. These findings reveal the profound impact of the electric field and framework flexibility on the separation of Li+ and Mg2+, offering critical insights for the potential application of flexible nanoporous materials in the selective extraction of Li+ from salt-lake brine.

10.
Acta Pharmacol Sin ; 45(3): 545-557, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37932403

RESUMO

The matrix glycoprotein thrombospondin-1 (THBS1) modulates nitric oxide (NO) signaling in endothelial cells. A high-salt diet induces deficiencies of NO production and bioavailability, thereby leading to endothelial dysfunction. In this study we investigated the changes of THBS1 expression and its pathological role in the dysfunction of mesenteric artery endothelial cells (MAECs) induced by a high-salt diet. Wild-type rats, and wild-type and Thbs1-/- mice were fed chow containing 8% w/w NaCl for 4 weeks. We showed that a high salt diet significantly increased THBS1 expression and secretion in plasma and MAECs, and damaged endothelium-dependent vasodilation of mesenteric resistance arteries in wild-type animals, but not in Thbs1-/- mice. In rat MAECs, we demonstrated that a high salt environment (10-40 mM) dose-dependently increased THBS1 expression accompanied by suppressed endothelial nitric oxide synthase (eNOS) and phospho-eNOS S1177 production as well as NO release. Blockade of transforming growth factor-ß1 (TGF-ß1) activity by a TGF-ß1 inhibitor SB 431542 reversed THBS1 up-regulation, rescued the eNOS decrease, enhanced phospho-eNOS S1177 expression, and inhibited Smad4 translocation to the nucleus. By conducting dual-luciferase reporter experiments in HEK293T cells, we demonstrated that Smad4, a transcription promoter, upregulated Thbs1 transcription. We conclude that THBS1 contributes to endothelial dysfunction in a high-salt environment and may be a potential target for treatment of high-salt-induced endothelium dysfunction.


Assuntos
Células Endoteliais , Cloreto de Sódio , Humanos , Ratos , Camundongos , Animais , Cloreto de Sódio/metabolismo , Células Endoteliais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Células HEK293 , Endotélio Vascular/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Vasodilatação , Artérias Mesentéricas , Trombospondinas/metabolismo , Óxido Nítrico/metabolismo
11.
Ann Plast Surg ; 93(3): e9-e25, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39158343

RESUMO

BACKGROUND: Fat grafting and repositioning may serve as a convenient, economical, and effective surgical method for correcting lower eyelid pouch with a tear trough deformity or lid-cheek junction. However, comprehensive systematic reviews and meta-analyses investigating the complications associated with this technique are lacking. OBJECTIVE: This study aimed to summarize and gather data on complications related to fat grafting and repositioning for the correction of tear trough deformity or lid-cheek junction in lower eyelid blepharoplasty. METHODS: A thorough search was performed across multiple databases including PubMed, Cochrane, Embase, ProQuest, Ovid, Scopus, and Web of Science. Specific inclusion and exclusion criteria were applied to screen the articles. The occurrence of complications was analyzed using a random-effects model. RESULTS: A total of 33 studies involving 4671 patients met the criteria for systematic evaluation and were included in this meta-analysis. The overall complication rates were 0.112 (95% confidence interval [CI]: 0.060-0.177) for total complications, 0.062 (95% CI: 0.003-0.172) for unsatisfactory correction or contour irregularity, 0.062 (95% CI: 0.009-0.151) for hematoma, swelling (not specified as bulbar conjunctiva), ecchymosis, or oozing of blood, and 0.024 (95% CI: 0.013-0.038) for reoperation. CONCLUSIONS: Fat grafting and repositioning for correcting a lower eyelid pouch with tear trough deformity or lid-cheek junction was associated with high rates of complications. Therefore, it is crucial to closely monitor the rates of unsatisfactory correction or contour irregularity, hematoma, swelling (not specified as bulbar conjunctiva), ecchymosis, or oozing of blood, and reoperation. In addition, effective communication with patients should be prioritized.


Assuntos
Tecido Adiposo , Blefaroplastia , Complicações Pós-Operatórias , Humanos , Blefaroplastia/métodos , Tecido Adiposo/transplante , Complicações Pós-Operatórias/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Pálpebras/cirurgia , Bochecha/cirurgia
12.
Nano Lett ; 23(12): 5770-5778, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37314049

RESUMO

Understanding the atomistic mechanisms of non-equilibrium processes during solid-state synthesis, such as nucleation and grain structure formation of a layered oxide phase, is a critical challenge for developing promising cathode materials such as Ni-rich layered oxide for Li-ion batteries. In this study, we found that the aluminum oxide coating layer transforms into lithium aluminate as an intermediate, which has favorable low interfacial energies with the layered oxide to promote the nucleation of the latter. The fast and uniform nucleation and formation of the layered oxide phase at relatively low temperatures were evidenced using solid-state nuclear magnetic resonance and in situ synchrotron X-ray diffraction. The resulting Ni-rich layered oxide cathode has fine primary particles, as visualized by three-dimensional tomography constructed using a focused-ion beam and scanning electron microscopy. The densely packed fine primary particles enable the excellent mechanical strength of the secondary particles, as demonstrated by in situ compression tests. This strategy provides a new approach for developing next-generation, high-strength battery materials.

13.
J Community Health Nurs ; 41(4): 256-264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38909288

RESUMO

We aimed to analyze the effects of exclusive breastfeeding duration on the occurrence and course of pneumonia in infants aged up to 6 months. Prospective case-control study. This study was conducted from August 2020 to August 2022 at a maternity and child health hospital in China. A total of 218 infants up to 6 months of age with pneumonia were included in the analyses. Health data were obtained using a hospitalization information system or an interview-based questionnaire. Univariate and multivariate logistic regression analyses were performed to analyze the data. The incidence of pneumonia, hospitalization duration, and costs to participants were significantly affected by the duration of exclusive breastfeeding (p < 0.01). The incidence of pneumonia among participants with different exclusive breastfeeding durations also differed significantly (p < 0.01). The shorter the duration of exclusive breastfeeding, the higher the incidence of pneumonia among infants. We found that the longer the exclusive breastfeeding duration in infants up to 6 months of age, the lower the recurrence of pneumonia, the shorter the hospital stay, and the lower the hospital costs. The rate of exclusive breastfeeding for infants up to 6 months of age should be increased as much as possible to reduce the occurrence of pneumonia and hospital costs.


Assuntos
Aleitamento Materno , Pneumonia , Humanos , Aleitamento Materno/estatística & dados numéricos , Estudos de Casos e Controles , Lactente , Feminino , Pneumonia/epidemiologia , Pneumonia/prevenção & controle , Masculino , Estudos Prospectivos , China/epidemiologia , Recém-Nascido , Incidência , Fatores de Tempo , Inquéritos e Questionários , Hospitalização/estatística & dados numéricos
14.
Phys Rev Lett ; 131(15): 156302, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897744

RESUMO

With the rapid development of ultrafast experimental techniques for the research of carrier dynamics in solid-state systems, a microscopic understanding of the related phenomena, particularly a first-principle calculation, is highly desirable. Nonadiabatic molecular dynamics (NAMD) offers a real-time direct simulation of the carrier transfer or carrier thermalization. However, when applied to a periodic supercell, there is no cross-k-point transitions during the NAMD simulation. This often leads to a significant underestimation of the transition rate with the single-k-point band structure in a supercell. In this work, based on the surface hopping scheme used for NAMD, we propose a practical method to enable the cross-k transitions for a periodic system. We demonstrate our formalism by showing that the hot electron thermalization process by the multi-k-point NAMD in a small silicon supercell is equivalent to such simulation in a large supercell with a single Γ point. The simulated hot carrier thermalization process of the bulk silicon is compared with the recent ultrafast experiments, which shows excellent agreements. We have also demonstrated our method for the hot carrier coolings in the amorphous silicons and the GaAlAs_{2} solid solutions with the various cation distributions.

15.
Org Biomol Chem ; 21(24): 5063-5071, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37272329

RESUMO

As a chronic inflammatory disease, rheumatoid arthritis (RA) can cause progressive damage to joints and various organs. Hydrogen peroxide plays a significant role in the pathogenesis and progression of RA and thus serves as a biomarker for diagnosing this disease. Although fluorescent probes have emerged as promising tools for detecting H2O2, most available ones suffer from the aggregation-caused quenching (ACQ) effect, short-wavelength emission, low sensitivity, and poor water solubility. Herein, a new type of "turn-on" AIE probe based on excited state intramolecular proton transfer (ESIPT) was developed, with phenylboronic acid pinacol ester-appended quinolinium as the H2O2 recognition site, which is in the quenched state due to the twisted intramolecular charge transfer (TICT) effect. The probe HTQ-R exhibits good water solubility, high sensitivity, a low detection limit (210 nM), rapid response ability, and good biocompatibility towards hydrogen peroxide, and has shown the ability to accurately target mitochondria. Furthermore, HTQ-R was successfully used to detect exogenous and endogenous hydrogen peroxide in living cells, which enabled real-time monitoring of H2O2 in RA mice, demonstrating its potential significance in the diagnosis and treatment of RA.


Assuntos
Corantes Fluorescentes , Prótons , Animais , Camundongos , Humanos , Peróxido de Hidrogênio , Mitocôndrias , Água , Células HeLa
16.
Eur J Nutr ; 62(5): 2177-2194, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37024732

RESUMO

PURPOSE: Pu-erh tea can be classified into raw pu-erh tea and ripened pu-erh tea. Theabrownin (TB) is one of the major components of pu-erh tea. The difference of the anti-obesity activity between raw pu-erh tea TB (R-TB) and ripened pu-erh tea TB (F-TB) has not been comprehensively investigated yet. Therefore, this article aimed to systemically study the anti-obesity activity and the underlying mechanism of R-TB and F-TB. METHOD: High-fat diet (HFD)-induced C57BL/6J mice with obesity were gavaged with R-TB or F-TB to assess the effect of R-TB and F-TB on the amelioration of obesity, the expression of lipid metabolism-related genes, and the regulation of gut flora imbalance. RESULTS: Administration of both R-TB and F-TB could suppress body weight gain, improve insulin sensitivity and glucose homeostasis, regulate the lipid level and reduce the chronic inflammation in obese mice. The underlying anti-obesity mechanism of R-TB and F-TB might involve the regulation of lipogenesis and lipolysis, amelioration of the gut microbiota disorder and promotion of microbial metabolism. Interestingly, R-TB was more efficient in the regulation of blood glucose, reduction of inflammation and suppression of partial adipogenesis-related genes and protein, while F-TB was more effective in the inhibition of lipolysis-related genes and protein. In addition, F-TB might be more effective in adjusting the dysbacteria caused by HFD back to normal by promoting the proliferation of the beneficial microbiota, such as Lactobacillus and Lachnospiraceae_NK4A136_group. CONCLUSION: Taken together, both R-TB and F-TB had the potential to be developed as beneficial dietary supplements or functional foods for ameliorating obesity and obesity-related metabolic disorders, but their effects and the ability to regulate the intestinal flora varied.


Assuntos
Microbioma Gastrointestinal , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Chá , Camundongos Endogâmicos C57BL , Obesidade , Inflamação
17.
J Integr Neurosci ; 22(6): 153, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38176930

RESUMO

Spinal cord injury (SCI) is a serious central nervous system (CNS) injury disease related to hypoxia-ischemia and inflammation. It is characterized by excessive reactive oxygen species (ROS) production, oxidative damage to nerve cells, and mitochondrial dysfunction. Mitochondria serve as the primary cellular origin of ROS, wherein the electron transfer chain complexes within oxidative phosphorylation frequently encounter electron leakage. These leaked electrons react with molecular oxygen, engendering the production of ROS, which culminates in the occurrence of oxidative stress. Oxidative stress is one of the common forms of secondary injury after SCI. Mitochondrial oxidative stress can lead to impaired mitochondrial function and disrupt cellular signal transduction pathways. Hence, restoring mitochondrial electron transport chain (ETC), reducing ROS production and enhancing mitochondrial function may be potential strategies for the treatment of SCI. This article focuses on the pathophysiological role of mitochondrial oxidative stress in SCI and evaluates in detail the neuroprotective effects of various mitochondrial-targeted antioxidant therapies in SCI, including both drug and non-drug therapy. The objective is to provide valuable insights and serve as a valuable reference for future research in the field of SCI.


Assuntos
Traumatismos da Medula Espinal , Humanos , Espécies Reativas de Oxigênio/metabolismo , Traumatismos da Medula Espinal/metabolismo , Estresse Oxidativo , Antioxidantes/farmacologia , Neuroproteção , Medula Espinal/metabolismo
18.
Int J Mol Sci ; 24(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37047790

RESUMO

Radiation-induced brain injury is a serious complication with complex pathogenesis that may accompany radiotherapy of head and neck tumors. Although studies have shown that calcium (Ca2+) signaling may be involved in the occurrence and development of radiation-induced brain injury, the underlying molecular mechanisms are not well understood. In this study, we used real-time quantitative polymerase chain reaction and Western blotting assays to verify our previous finding using next-generation sequencing that the mRNA and protein expression levels of Orai3 in rat brain microvascular endothelial cells (rBMECs) increased after X-ray irradiation. We next explored the role of Orai3 and Orai3-mediated store-operated Ca2+ entry (SOCE) in radiation-induced brain injury. Primary cultured rBMECs derived from wild-type and Orai3 knockout (Orai3(-/-)) Sprague-Dawley rats were used for in vitro experiments. Orai3-mediated SOCE was significantly increased in rBMECs after X-ray irradiation. However, X-ray irradiation-induced SOCE increase was markedly reduced in Orai3 knockout rBMECs, and the percentage of BTP2 (a nonselective inhibitor of Orai channels)-inhibited SOCE was significantly decreased in Orai3 knockout rBMECs. Functional studies indicated that X-ray irradiation decreased rBMEC proliferation, migration, and tube formation (a model for assessing angiogenesis) but increased rBMEC apoptosis, all of which were ameliorated by BTP2. In addition, occurrences of all four functional deficits were suppressed in X-ray irradiation-exposed rBMECs derived from Orai3(-/-) rats. Cerebrovascular damage caused by whole-brain X-ray irradiation was much less in Orai3(-/-) rats than in wild-type rats. These findings provide evidence that Orai3-mediated SOCE plays an important role in radiation-induced rBMEC damage and brain injury and suggest that Orai3 may warrant development as a potential therapeutic target for reducing or preventing radiation-induced brain injury.


Assuntos
Lesões Encefálicas , Canais de Cálcio , Células Endoteliais , Animais , Ratos , Encéfalo/metabolismo , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Células Endoteliais/metabolismo , Ratos Sprague-Dawley
19.
Cell Mol Life Sci ; 78(1): 373-384, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32318758

RESUMO

Faithful chromosome segregation during mitosis requires the correct assembly of kinetochore on the centromere. CENP-A is a variant of histone H3, which specializes the centromere region on chromatin and mediates the kinetochore assembly. The Mis18 complex plays a critical role in initiating the centromere loading of the newly-synthesized CENP-A. However, it remains unclear how Mis18 complex (spMis18, spMis16 and spMis19) is located to the centromere to license the recruitment of Cnp1CENP-A in Schizosaccharomyces pombe. We found that spMis18 directly binds to nucleosomal DNA through its extreme C-terminus and interacts with H2A-H2B dimer via the acidic region on the surface of its Yippee-like domain. Live-cell imaging confirmed that mutation of the acidic region and deletion of the extreme C-terminus significantly impairs the localization of spMis18 and Cnp1 to the centromere and delays chromosome segregation during mitosis. Our findings illustrate that the interaction of spMis18 with histone H2A-H2B and DNA plays important roles in the recruitment of spMis18 and Cnp1 to the centromere in fission yeast.


Assuntos
Proteínas de Transporte/metabolismo , DNA/metabolismo , Histonas/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/metabolismo , Proteínas de Transporte/química , Proteínas de Transporte/genética , Centrômero/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Segregação de Cromossomos , Cristalografia por Raios X , DNA/química , Dimerização , Histonas/genética , Microscopia de Fluorescência , Mitose , Simulação de Dinâmica Molecular , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Mutagênese , Ligação Proteica , Domínios Proteicos , Estrutura Terciária de Proteína , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/química , Proteínas de Schizosaccharomyces pombe/genética , Imagem com Lapso de Tempo
20.
Immun Ageing ; 19(1): 42, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167546

RESUMO

BACKGROUND: Assessment of immune function is of key importance in recognition of disease or healthy status, which still faces challenge in clinical practice. We conducted a 10-center study to investigate lymphocyte parameters including the number, phenotype and IFN-γ-producing ability, and routine laboratory indicators by using the standard method. RESULTS: Although the heterogeneity of lymphocyte parameters was widely found, we have established the normal ranges of these parameters by using pooled data which showed no significant difference among centers. Cluster analysis of 35 parameters found 3 interesting clusters which represented different immunological status. Cluster 1 (parameters: IFN-γ+CD4+ T cell percentage and IFN-γ+CD8+ T cell percentage) represented current lymphocyte function, which was associated with indicators such as body mass index and red blood cell; Cluster 2 (parameters: NK cell number and CD45RA+CD4+ T cell percentage) represented potential of lymphocytes, which was associated with indicators such as albumin and high-density lipoprotein. Cluster 3 (parameters: HLA-DR+CD8+ T cell percentage) represented inflammatory status, which was associated with indicators such as low-density lipoprotein, globulin and age. Correlation analysis found that nutritional indicator albumin is significantly positively correlated with lymphocyte potential. Triglyceride and body mass index were positively correlated with current lymphocyte function rather than lymphocyte potential. The loss of CD8+ T cells was extremely pronounced with increasing age and was one of the most important factors to cause immunosenescence, which may be associated with increased glucose. CONCLUSIONS: We have established the normal ranges of lymphocyte parameters in different areas. This study elucidates the key indicators used to reflect the current function or potential of lymphocytes, which may provide a valuable clue for how to keep immunity healthy.

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