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1.
Cell ; 178(1): 176-189.e15, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31155231

RESUMO

RLR-mediated type I IFN production plays a pivotal role in elevating host immunity for viral clearance and cancer immune surveillance. Here, we report that glycolysis, which is inactivated during RLR activation, serves as a barrier to impede type I IFN production upon RLR activation. RLR-triggered MAVS-RIG-I recognition hijacks hexokinase binding to MAVS, leading to the impairment of hexokinase mitochondria localization and activation. Lactate serves as a key metabolite responsible for glycolysis-mediated RLR signaling inhibition by directly binding to MAVS transmembrane (TM) domain and preventing MAVS aggregation. Notably, lactate restoration reverses increased IFN production caused by lactate deficiency. Using pharmacological and genetic approaches, we show that lactate reduction by lactate dehydrogenase A (LDHA) inactivation heightens type I IFN production to protect mice from viral infection. Our study establishes a critical role of glycolysis-derived lactate in limiting RLR signaling and identifies MAVS as a direct sensor of lactate, which functions to connect energy metabolism and innate immunity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína DEAD-box 58/antagonistas & inibidores , Proteína DEAD-box 58/metabolismo , Ácido Láctico/farmacologia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo , Animais , Feminino , Glicólise , Células HEK293 , Humanos , Interferon beta/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células RAW 264.7 , Receptores Imunológicos , Transdução de Sinais/efeitos dos fármacos , Transfecção
2.
Nature ; 623(7987): 633-642, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938770

RESUMO

Trimethylation of histone H3 lysine 9 (H3K9me3) is crucial for the regulation of gene repression and heterochromatin formation, cell-fate determination and organismal development1. H3K9me3 also provides an essential mechanism for silencing transposable elements1-4. However, previous studies have shown that canonical H3K9me3 readers (for example, HP1 (refs. 5-9) and MPP8 (refs. 10-12)) have limited roles in silencing endogenous retroviruses (ERVs), one of the main transposable element classes in the mammalian genome13. Here we report that trinucleotide-repeat-containing 18 (TNRC18), a poorly understood chromatin regulator, recognizes H3K9me3 to mediate the silencing of ERV class I (ERV1) elements such as LTR12 (ref. 14). Biochemical, biophysical and structural studies identified the carboxy-terminal bromo-adjacent homology (BAH) domain of TNRC18 (TNRC18(BAH)) as an H3K9me3-specific reader. Moreover, the amino-terminal segment of TNRC18 is a platform for the direct recruitment of co-repressors such as HDAC-Sin3-NCoR complexes, thus enforcing optimal repression of the H3K9me3-demarcated ERVs. Point mutagenesis that disrupts the TNRC18(BAH)-mediated H3K9me3 engagement caused neonatal death in mice and, in multiple mammalian cell models, led to derepressed expression of ERVs, which affected the landscape of cis-regulatory elements and, therefore, gene-expression programmes. Collectively, we describe a new H3K9me3-sensing and regulatory pathway that operates to epigenetically silence evolutionarily young ERVs and exert substantial effects on host genome integrity, transcriptomic regulation, immunity and development.


Assuntos
Retrovirus Endógenos , Inativação Gênica , Histonas , Peptídeos e Proteínas de Sinalização Intracelular , Lisina , Retroelementos , Animais , Humanos , Camundongos , Cromatina/genética , Cromatina/metabolismo , Proteínas Correpressoras/metabolismo , Retrovirus Endógenos/genética , Epigênese Genética , Perfilação da Expressão Gênica , Genoma/genética , Histona Desacetilases/metabolismo , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisina/metabolismo , Metilação , Domínios Proteicos , Retroelementos/genética , Sequências Repetidas Terminais/genética , Animais Recém-Nascidos , Linhagem Celular
3.
Mol Cell ; 81(18): 3803-3819.e7, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34547240

RESUMO

Mitochondrial dynamics regulated by mitochondrial fusion and fission maintain mitochondrial functions, whose alterations underline various human diseases. Here, we show that inositol is a critical metabolite directly restricting AMPK-dependent mitochondrial fission independently of its classical mode as a precursor for phosphoinositide generation. Inositol decline by IMPA1/2 deficiency elicits AMPK activation and mitochondrial fission without affecting ATP level, whereas inositol accumulation prevents AMPK-dependent mitochondrial fission. Metabolic stress or mitochondrial damage causes inositol decline in cells and mice to elicit AMPK-dependent mitochondrial fission. Inositol directly binds to AMPKγ and competes with AMP for AMPKγ binding, leading to restriction of AMPK activation and mitochondrial fission. Our study suggests that the AMP/inositol ratio is a critical determinant for AMPK activation and establishes a model in which AMPK activation requires inositol decline to release AMPKγ for AMP binding. Hence, AMPK is an inositol sensor, whose inactivation by inositol serves as a mechanism to restrict mitochondrial fission.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Inositol/metabolismo , Dinâmica Mitocondrial/fisiologia , Proteínas Quinases Ativadas por AMP/fisiologia , Animais , Linhagem Celular , Humanos , Inositol/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Células PC-3 , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Estresse Fisiológico/fisiologia
4.
Mol Cell ; 80(2): 263-278.e7, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33022274

RESUMO

Cancer metastasis accounts for the major cause of cancer-related deaths. How disseminated cancer cells cope with hostile microenvironments in secondary site for full-blown metastasis is largely unknown. Here, we show that AMPK (AMP-activated protein kinase), activated in mouse metastasis models, drives pyruvate dehydrogenase complex (PDHc) activation to maintain TCA cycle (tricarboxylic acid cycle) and promotes cancer metastasis by adapting cancer cells to metabolic and oxidative stresses. This AMPK-PDHc axis is activated in advanced breast cancer and predicts poor metastasis-free survival. Mechanistically, AMPK localizes in the mitochondrial matrix and phosphorylates the catalytic alpha subunit of PDHc (PDHA) on two residues S295 and S314, which activates the enzymatic activity of PDHc and alleviates an inhibitory phosphorylation by PDHKs, respectively. Importantly, these phosphorylation events mediate PDHc function in cancer metastasis. Our study reveals that AMPK-mediated PDHA phosphorylation drives PDHc activation and TCA cycle to empower cancer cells adaptation to metastatic microenvironments for metastasis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Ciclo do Ácido Cítrico , Complexo Piruvato Desidrogenase/metabolismo , Animais , Domínio Catalítico , Linhagem Celular Tumoral , Sobrevivência Celular , Ativação Enzimática , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Fosforilação , Fosfosserina/metabolismo , Transdução de Sinais , Estresse Fisiológico , Análise de Sobrevida
5.
Genome Res ; 34(5): 740-756, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38744529

RESUMO

Although DNA N 6-adenine methylation (6mA) is best known in prokaryotes, its presence in eukaryotes has recently generated great interest. Biochemical and genetic evidence supports that AMT1, an MT-A70 family methyltransferase (MTase), is crucial for 6mA deposition in unicellular eukaryotes. Nonetheless, the 6mA transmission mechanism remains to be elucidated. Taking advantage of single-molecule real-time circular consensus sequencing (SMRT CCS), here we provide definitive evidence for semiconservative transmission of 6mA in Tetrahymena thermophila In wild-type (WT) cells, 6mA occurs at the self-complementary ApT dinucleotide, mostly in full methylation (full-6mApT); after DNA replication, hemi-methylation (hemi-6mApT) is transiently present on the parental strand, opposite to the daughter strand readily labeled by 5-bromo-2'-deoxyuridine (BrdU). In ΔAMT1 cells, 6mA predominantly occurs as hemi-6mApT. Hemi-to-full conversion in WT cells is fast, robust, and processive, whereas de novo methylation in ΔAMT1 cells is slow and sporadic. In Tetrahymena, regularly spaced 6mA clusters coincide with the linker DNA of nucleosomes arrayed in the gene body. Importantly, in vitro methylation of human chromatin by the reconstituted AMT1 complex recapitulates preferential targeting of hemi-6mApT sites in linker DNA, supporting AMT1's intrinsic and autonomous role in maintenance methylation. We conclude that 6mA is transmitted by a semiconservative mechanism: full-6mApT is split by DNA replication into hemi-6mApT, which is restored to full-6mApT by AMT1-dependent maintenance methylation. Our study dissects AMT1-dependent maintenance methylation and AMT1-independent de novo methylation, reveals a 6mA transmission pathway with a striking similarity to 5-methylcytosine (5mC) transmission at the CpG dinucleotide, and establishes 6mA as a bona fide eukaryotic epigenetic mark.


Assuntos
Adenina , Metilação de DNA , Tetrahymena thermophila , Tetrahymena thermophila/genética , Tetrahymena thermophila/metabolismo , Adenina/metabolismo , Adenina/análogos & derivados , Replicação do DNA , DNA de Protozoário/genética , DNA de Protozoário/metabolismo
6.
Stem Cells ; 42(6): 554-566, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38613477

RESUMO

Microtia is a congenital auricle dysplasia with a high incidence and tissue engineering technology provides a promising strategy to reconstruct auricles. We previously described that the engineered cartilage constructed from microtia chondrocytes exhibited inferior levels of biochemical and biomechanical properties, which was proposed to be resulted of the decreased migration ability of microtia chondrocytes. In the current study, we found that Rho GTPase members were deficient in microtia chondrocytes. By overexpressing RhoA, Rac1, and CDC42, respectively, we further demonstrated that RhoA took great responsibility for the decreased migration ability of microtia chondrocytes. Moreover, we constructed PGA/PLA scaffold-based cartilages to verify the chondrogenic ability of RhoA overexpressed microtia chondrocytes, and the results showed that overexpressing RhoA was of limited help in improving the quality of microtia chondrocyte engineered cartilage. However, coculture of adipose-derived stem cells (ADSCs) significantly improved the biochemical and biomechanical properties of engineered cartilage. Especially, coculture of RhoA overexpressed microtia chondrocytes and ADSCs produced an excellent effect on the wet weight, cartilage-specific extracellular matrix, and biomechanical property of engineered cartilage. Furthermore, we presented that coculture of RhoA overexpressed microtia chondrocytes and ADSCs combined with human ear-shaped PGA/PLA scaffold and titanium alloy stent fabricated by CAD/CAM and 3D printing technology effectively constructed and maintained auricle structure in vivo. Collectively, our results provide evidence for the essential role of RhoA in microtia chondrocytes and a developed strategy for the construction of patient-specific tissue-engineered auricular cartilage.


Assuntos
Condrócitos , Técnicas de Cocultura , Microtia Congênita , Engenharia Tecidual , Proteína rhoA de Ligação ao GTP , Condrócitos/metabolismo , Condrócitos/citologia , Humanos , Engenharia Tecidual/métodos , Proteína rhoA de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/genética , Microtia Congênita/metabolismo , Microtia Congênita/genética , Cartilagem da Orelha/citologia , Cartilagem da Orelha/metabolismo , Células-Tronco/metabolismo , Células-Tronco/citologia , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Condrogênese/genética , Masculino , Alicerces Teciduais/química , Feminino
7.
J Cell Mol Med ; 28(9): e18357, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38683127

RESUMO

In our previous study, intranuclear cardiac troponin I (cTnI) may function as a co-factor of Yin Yang 1(YY1). Here, we aimed to explore the role of intranuclear cTnI in ageing hearts. Nuclear translocation of cTnI was demonstrated using Western blot and immunofluorescence. The potential nuclear localization sequences (NLSs) of cTnI were predicted by a web server and then verified in 293T cells by putative NLS-eGFP-GST and NLS-mutant transfection. The ratio of Nuclear cTnI/ Total cTnI (Nu/T) decreased significantly in ageing hearts, accompanied with ATG5-decline-related impaired cardiac autophagy. RNA sequencing was performed in cTnI knockout hearts. The differential expressed genes (DEGs) were analysed by overlapping with YY1 ChIP-sequencing data. cTnI gain and loss experiments in vitro determined those filtered DEGs' expression levels. A strong correlation was found between expression patterns cTnI and FOS. Using ChIP-q-PCR, we demonstrated that specific binding DNA sequences of cTnI were enriched in the FOS promoter -299 to -157 region. It was further verified that pcDNA3.1 (-)-cTnI could increase the promoter activity of FOS by using luciferase report assay. At last, we found that FOS can regulate the ATG5 (autophagy-related gene 5) gene by using a luciferase report assay. Taken together, our results indicate that decreased intranuclear cTnI in ageing hearts may cause impaired cardiac autophagy through the FOS/ATG5 pathway.


Assuntos
Envelhecimento , Proteína 5 Relacionada à Autofagia , Autofagia , Núcleo Celular , Miocárdio , Troponina I , Troponina I/metabolismo , Troponina I/genética , Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 5 Relacionada à Autofagia/genética , Envelhecimento/metabolismo , Envelhecimento/genética , Animais , Miocárdio/metabolismo , Humanos , Núcleo Celular/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Camundongos , Células HEK293 , Masculino , Regiões Promotoras Genéticas , Regulação da Expressão Gênica , Miócitos Cardíacos/metabolismo , Camundongos Knockout
8.
J Cell Mol Med ; 28(11): e18443, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38837873

RESUMO

The human auricle has a complex structure, and microtia is a congenital malformation characterized by decreased size and loss of elaborate structure in the affected ear with a high incidence. Our previous studies suggest that inadequate cell migration is the primary cytological basis for the pathogenesis of microtia, however, the underlying mechanism is unclear. Here, we further demonstrate that microtia chondrocytes show a decreased directional persistence during cell migration. Directional persistence can define a leading edge associated with oriented movement, and any mistakes would affect cell function and tissue morphology. By the screening of motility-related genes and subsequent confirmations, active Rac1 (Rac1-GTP) is identified to be critical for the impaired directional persistence of microtia chondrocytes migration. Moreover, Rho guanine nucleotide exchange factors (GEFs) and Rho GTPase-activating proteins (GAPs) are detected, and overexpression of Tiam1 significantly upregulates the level of Rac1-GTP and improves directional migration in microtia chondrocytes. Consistently, decreased expression patterns of Tiam1 and active Rac1 are found in microtia mouse models, Bmp5se/J and Prkralear-3J/GrsrJ. Collectively, our results provide new insights into microtia development and therapeutic strategies of tissue engineering for microtia patients.


Assuntos
Movimento Celular , Condrócitos , Microtia Congênita , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T , Proteínas rac1 de Ligação ao GTP , Animais , Feminino , Humanos , Masculino , Camundongos , Condrócitos/metabolismo , Condrócitos/citologia , Microtia Congênita/metabolismo , Microtia Congênita/genética , Microtia Congênita/patologia , Modelos Animais de Doenças , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/metabolismo , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/genética
9.
J Biol Chem ; 299(4): 104570, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36870679

RESUMO

Liver kinase B1 (LKB1) is a serine-threonine kinase that participates in multiple cellular and biological processes, including energy metabolism, cell polarity, cell proliferation, cell migration, and many others. LKB1 is initially identified as a germline-mutated causative gene in Peutz-Jeghers syndrome and is commonly regarded as a tumor suppressor due to frequent inactivation in a variety of cancers. LKB1 directly binds and activates its downstream kinases including the AMP-activated protein kinase (AMPK) and AMPK-related kinases by phosphorylation, which has been intensively investigated for the past decades. An increasing number of studies have uncovered the posttranslational modifications (PTMs) of LKB1 and consequent changes in its localization, activity, and interaction with substrates. The alteration in LKB1 function as a consequence of genetic mutations and aberrant upstream signaling regulation leads to tumor development and progression. Here, we review current knowledge about the mechanism of LKB1 in cancer and the contributions of PTMs, such as phosphorylation, ubiquitination, SUMOylation, acetylation, prenylation, and others, to the regulation of LKB1 function, offering new insights into the therapeutic strategies in cancer.


Assuntos
Proteínas Quinases Ativadas por AMP , Neoplasias , Processamento de Proteína Pós-Traducional , Humanos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Fígado/metabolismo , Síndrome de Peutz-Jeghers/genética , Síndrome de Peutz-Jeghers/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Neoplasias/enzimologia
10.
Small ; : e2310608, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461532

RESUMO

Depression is a significant global health concern that remains inadequately treated due to the limited effectiveness of conventional drug therapies. One potential therapeutic agent, hypericin (HYP), is identified as an effective natural antidepressant. However, its poor water solubility, low bioavailability, and limited ability to penetrate the brain parenchyma have hindered its clinical application. To address these shortcomings and enhance the therapeutic efficacy of HYP, it is loaded onto black phosphorus nanosheets (BP) modified with the neural cell-targeting peptide RVG29 to synthesize a nanoplatform named BP-RVG29@HYP (BRH). This platform served as a nanocarrier for HYP and integrated the advantages of BP with advanced delivery methods and precise targeting strategies. Under the influence of 808 nm near-infrared irradiation (NIR), BRH effectively traversed an in vitro BBB model. In vivo experiments validated these findings, demonstrating that treatment with BRH significantly alleviated depressive-like behaviors and oxidative stress in mice. Importantly, BRH exhibited an excellent safety profile, causing minimal adverse effects, which highlighted its potential as a promising therapeutic agent. In brief, this novel nanocarrier holds great promise in the development of antidepressant drugs and can create new avenues for the treatment of depression.

11.
Hum Reprod ; 39(2): 310-325, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38011909

RESUMO

STUDY QUESTION: What is the mechanism behind cryoinjury in human sperm, particularly concerning the interplay between reactive oxygen species (ROS) and autophagy, and how does it subsequently affect sperm fate? SUMMARY ANSWER: The freeze-thaw operation induces oxidative stress by generating abundant ROS, which impairs sperm motility and activates autophagy, ultimately guiding the sperm toward programmed cell death such as apoptosis and necrosis, as well as triggering premature capacitation. WHAT IS KNOWN ALREADY: Both ROS-induced oxidative stress and autophagy are thought to exert an influence on the quality of frozen-thawed sperm. STUDY DESIGN, SIZE, DURATION: Overall, 84 semen specimens were collected from young healthy fertile males, with careful quality evaluation. The specimens were split into three groups to investigate the ROS-induced cryoinjury: normal control without any treatment, sperm treated with 0.5 mM hydrogen peroxide (H2O2) for 1 h, and sperm thawed following cryopreservation. Samples from 48 individuals underwent computer-assisted human sperm analysis (CASA) to evaluate sperm quality in response to the treatments. Semen samples from three donors were analyzed for changes in the sperm proteome after H2O2 treatment, and another set of samples from three donors were analyzed for changes following the freeze-thaw process. The other 30 samples were used for fluorescence-staining and western blotting. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm motility parameters, including progressive motility (PR %) and total motility (PR + NP %), were evaluated using the CASA system on a minimum of 200 spermatozoa. The proteomic profiles were determined with label-free mass spectrometry (MS/MS) and protein identification was performed via ion search against the NCBI human database. Subsequently, comprehensive bioinformatics was applied to detect significant proteomic changes and functional enrichment. Fluorescence-staining and western blot analyses were also conducted to confirm the proteomic changes on selected key proteins. The ROS level was measured using 2',7'-dichlorodihydrofluorescein diacetate labeling and the abundance of bioactive mitochondria was determined by evaluating the inner mitochondrial membrane potential (MMP) level. Molecular behaviors of sequestosome-1 (p62 or SQSTM1) and microtubule-associated proteins 1A/1B light chain 3 (LC3) were monitored to evaluate the state of apoptosis in human sperm. Fluorescent probes oxazole yellow (YO-PRO-1) and propidium iodide (PI) were utilized to monitor programmed cell death, namely apoptosis and necrosis. Additionally, gradient concentrations of antioxidant coenzyme Q10 (CoQ10) were introduced to suppress ROS impacts on sperm. MAIN RESULTS AND THE ROLE OF CHANCE: The CASA analysis revealed a significant decrease in sperm motility for both the H2O2-treatment and freeze-thaw groups. Fluorescence staining showed that high ROS levels were produced in the treated sperm and the MMPs were largely reduced. The introduction of CoQ10 at concentrations of 20 and 30 µM resulted in a significant rescue of progressive motility (P < 0.05). The result suggested that excessive ROS could be the major cause of sperm motility impairment, likely by damaging mitochondrial energy generation. Autophagy was significantly activated in sperm when they were under oxidative stress, as evidenced by the upregulation of p62 and the increased conversion of LC3 as well as the upregulation of several autophagy-related proteins, such as charged multivesicular body protein 2a, mitochondrial import receptor subunit TOM22 homolog, and WD repeat domain phosphoinositide-interacting protein 2. Additionally, fluorescent staining indicated the occurrence of apoptosis and necrosis in both H2O2-treated sperm and post-thaw sperm. The cell death process can be suppressed when CoQ10 is introduced, which consolidates the view that ROS could be the major contributor to sperm cryoinjury. The freeze-thaw process could also initiate sperm premature capacitation, demonstrated by the prominent increase in tyrosine phosphorylated proteins, verified with anti-phosphotyrosine antibody and immunofluorescence assays. The upregulation of capacitation-related proteins, such as hyaluronidase 3 and Folate receptor alpha, supported this finding. LARGE SCALE DATA: The data underlying this article are available in the article and its online supplementary material. LIMITATIONS, REASONS FOR CAUTION: The semen samples were obtained exclusively from young, healthy, and fertile males with progressive motility exceeding 60%, which might overemphasize the positive effects while possibly neglecting the negative impacts of cryoinjury. Additionally, the H2O2 treatment conditions in this study may not precisely mimic the oxidative stress experienced by sperm after thawing from cryopreservation, potentially resulting in the omission of certain molecular alterations. WIDER IMPLICATIONS OF THE FINDINGS: This study provides substantial proteomic data for a comprehensive and deeper understanding of the impact of cryopreservation on sperm quality. It will facilitate the design of optimal protocols for utilizing cryopreserved sperm to improve applications, such as ART, and help resolve various adverse situations caused by chemotherapy, radiotherapy, and surgery. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from the Major Innovation Project of Research Institute of National Health Commission (#2022GJZD01-3) and the National Key R&D Program of China (#2018YFC1003600). All authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Humanos , Espécies Reativas de Oxigênio/metabolismo , Sêmen/metabolismo , Motilidade dos Espermatozoides , Peróxido de Hidrogênio , Proteômica , Espectrometria de Massas em Tandem , Espermatozoides/metabolismo , Estresse Oxidativo , Criopreservação/métodos , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Necrose/metabolismo
12.
Glob Chang Biol ; 30(4): e17274, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605677

RESUMO

Climate change and other anthropogenic disturbances are increasing liana abundance and biomass in many tropical and subtropical forests. While the effects of living lianas on species diversity, ecosystem carbon, and nutrient dynamics are receiving increasing attention, the role of dead lianas in forest ecosystems has been little studied and is poorly understood. Trees and lianas coexist as the major woody components of forests worldwide, but they have very different ecological strategies, with lianas relying on trees for mechanical support. Consequently, trees and lianas have evolved highly divergent stem, leaf, and root traits. Here we show that this trait divergence is likely to persist after death, into the afterlives of these organs, leading to divergent effects on forest biogeochemistry. We introduce a conceptual framework combining horizontal, vertical, and time dimensions for the effects of liana proliferation and liana tissue decomposition on ecosystem carbon and nutrient cycling. We propose a series of empirical studies comparing traits between lianas and trees to answer questions concerning the influence of trait afterlives on the decomposability of liana and tree organs. Such studies will increase our understanding of the contribution of lianas to terrestrial biogeochemical cycling, and help predict the effects of their increasing abundance.


Assuntos
Ecossistema , Clima Tropical , Florestas , Árvores , Carbono
13.
FASEB J ; 37(5): e22908, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37039784

RESUMO

Peroxisomal fatty acyl-CoA reductase 1 (FAR1) is a rate-limiting enzyme for ether lipid (EL) synthesis. Gene mutations in FAR1 cause a rare human disease. Furthermore, altered EL homeostasis has also been associated with various prevalent human diseases. Despite their importance in human health, the exact cellular functions of FAR1 and EL are not well-understood. Here, we report the generation and initial characterization of the first Far1 knockout (KO) mouse model. Far1 KO mice were subviable and displayed growth retardation. The adult KO male mice had smaller testes and were infertile. H&E and immunofluorescent staining showed fewer germ cells in seminiferous tubules. Round spermatids were present but no elongated spermatids or spermatozoa were observed, suggesting a spermatogenesis arrest at this stage. Large multi-nucleated giant cells (MGC) were found lining the lumen of seminiferous tubules with many of them undergoing apoptosis. The immunofluorescent signal of TEX14, an essential component of intercellular bridges (ICB) between developing germ cells, was greatly reduced and mislocalized in KO testis, suggesting the disrupted ICBs as an underlying cause of MGC formation. Integrative analysis of our total testis RNA-sequencing results and published single-cell RNA-sequencing data unveiled cell type-specific molecular alterations underlying the spermatogenesis arrest. Many genes essential for late germ cell development showed dramatic downregulation, whereas genes essential for extracellular matrix dynamics and cell-cell interactions were among the most upregulated genes. Together, this work identified the cell type-specific requirement of ELs in spermatogenesis and suggested a critical role of Far1/ELs in the formation/maintenance of ICB during meiosis.


Assuntos
Azoospermia , Éter , Camundongos , Animais , Masculino , Humanos , Camundongos Knockout , Espermatogênese/genética , Espermátides , Éteres , Etil-Éteres , Lipídeos , RNA , Fatores de Transcrição/genética
14.
Mol Cell Biochem ; 479(4): 963-973, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37266748

RESUMO

Decompensated cardiac hypertrophy is accompanied by impaired mitochondrial homeostasis, whether histone acetylation is involved in this process is yet to be determined. The role of HDAC1-mediated NRF1 histone deacetylation was investigated in transverse aortic constriction (TAC)-induced hypertrophy in rats and phenylephrine (PE)-induced hypertrophic cardiomyocytes. Administration of epigallocatechin-3-gallate (EGCG), an inhibitor of HDAC1, restored cardiac function, decreased heart/body weight and fibrosis, increased the ratio of mtDNA/nDNA and the percentage of LysoTracker+ CMs in TAC, compared with TAC without receiving EGCG. In PE-treated hypertrophic H9C2 cells, EGCG attenuated cell hypertrophy and increased LC3B II+MitoTracker+ puncta, as well as the ratio of mtDNA/nDNA. Interestingly, NRF1 but not PGC-1α expression was decreased in TAC- or PE-induced hypertrophic hearts or cells, respectively, while EGCG upregulated both NRF1 and PGC-1α in vitro. EGCG treatment also increased the interaction between PGC-1α and NRF1. In addition to inhibiting HDAC1 expression, EGCG decreased the binding of HDAC1 and increased the binding of acH3K9 or acH3K14 in the promotor regions of PGC-1α and NRF1. In neonatal rat cardiomyocytes, restored NRF1, TFAM and FUNDC1 were abolished by the overexpression of HDAC1. Collectively, data suggest that NRF1 reduction was averted by EGCG via inhibiting HDAC1-mediated histone deacetylation. Acetylation of NRF1 histone may play a key role in maintaining mitochondrial homeostasis associated with cardiac hypertrophy.


Assuntos
Cardiomegalia , Catequina/análogos & derivados , Histonas , Ratos , Animais , Histonas/metabolismo , Cardiomegalia/metabolismo , DNA Mitocondrial , Homeostase , Miócitos Cardíacos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo
15.
Environ Sci Technol ; 58(18): 7743-7757, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38652822

RESUMO

Permeabilities of various trace elements (TEs) through the blood-follicle barrier (BFB) play an important role in oocyte development. However, it has not been comprehensively described as well as its involved biological pathways. Our study aimed to construct a blood-follicle distribution model of the concerned TEs and explore their related biological pathways. We finally included a total of 168 women from a cohort of in vitro fertilization-embryo transfer conducted in two reproductive centers in Beijing City and Shandong Province, China. The concentrations of 35 TEs in both serum and follicular fluid (FF) samples from the 168 women were measured, as well as the multiomics features of the metabolome, lipidome, and proteome in both plasma and FF samples. Multiomics features associated with the transfer efficiencies of TEs through the BFB were selected by using an elastic net model and further utilized for pathway analysis. Various machine learning (ML) models were built to predict the concentrations of TEs in FF. Overall, there are 21 TEs that exhibited three types of consistent BFB distribution characteristics between Beijing and Shandong centers. Among them, the concentrations of arsenic, manganese, nickel, tin, and bismuth in FF were higher than those in the serum with transfer efficiencies of 1.19-4.38, while a reverse trend was observed for the 15 TEs with transfer efficiencies of 0.076-0.905, e.g., mercury, germanium, selenium, antimony, and titanium. Lastly, cadmium was evenly distributed in the two compartments with transfer efficiencies of 0.998-1.056. Multiomics analysis showed that the enrichment of TEs was associated with the synthesis and action of steroid hormones and the glucose metabolism. Random forest model can provide the most accurate predictions of the concentrations of TEs in FF among the concerned ML models. In conclusion, the selective permeability through the BFB for various TEs may be significantly regulated by the steroid hormones and the glucose metabolism. Also, the concentrations of some TEs in FF can be well predicted by their serum levels with a random forest model.


Assuntos
Aprendizado de Máquina , Oligoelementos , Humanos , Oligoelementos/metabolismo , Feminino , Líquido Folicular/metabolismo , Líquido Folicular/química , China , Multiômica
16.
Int J Hyperthermia ; 41(1): 2310017, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38350654

RESUMO

Objective: Gastric cancer with peritoneal metastasis is considered to be final stage gastric cancer. One current treatment approach for this condition is combined cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). However, the therapeutic mechanisms of HIPEC remain largely undescribed. Method: In order to assess the cellular effects of HIPEC in vitro, we treated AGS human gastric adenocarcinoma cells with or without 5-fluorouracil (5-Fu) at 37 °C or at 43 °C (hyperthermic temperature) for 1 h followed by incubation at 37 °C for 23 h. The impacts of hyperthermia/5-Fu on apoptosis, cell survival signals, oxidative stress, chemoresistance-related proteins and programmed death-ligand 1 (PD-L1) expression were measured. Results: Our results showed that hyperthermia potentiates 5-Fu-mediated cytotoxicity in AGS cells. Furthermore, the combination of 5-Fu and hyperthermia reduces levels of both phosphorylated STAT3 and STAT3, while increasing the levels of phosphorylated Akt and ERK. In addition, 5-Fu/hyperthermia enhances reactive oxygen species and suppresses superoxide dismutase 1. Chemoresistance-related proteins, such as multidrug resistance 1 and thymidylate synthase, are also suppressed by 5-Fu/hyperthermia. Interestingly, hyperthermia enhances 5-Fu-mediated induction of glycosylated PD-L1, but 5-Fu-mediated upregulation of PD-L1 surface expression is prevented by hyperthermia. Conclusion: Taken together, our findings provide insights that may aid in the development of novel therapeutic strategies and enhanced therapeutic efficacy of HIPEC.


Assuntos
Hipertermia Induzida , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Antígeno B7-H1/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Hipertermia Induzida/métodos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada
17.
J Nanobiotechnology ; 22(1): 122, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504208

RESUMO

Endocrine therapy is standard for hormone receptor-positive (HR+) breast cancer treatment. However, current strategies targeting estrogen signaling pay little attention to estradiol metabolism in the liver and is usually challenged by treatment failure. In a previous study, we demonstrated that the natural compound naringenin (NAR) inhibited HR+ breast cancer growth by activating estrogen sulfotransferase (EST) expression in the liver. Nevertheless, the poor water solubility, low bio-barrier permeability, and non-specific distribution limited its clinical application, particularly for oral administration. Here, a novel nano endocrine drug NAR-cell penetrating peptide-galactose nanoparticles (NCG) is reported. We demonstrated that NCG presented specific liver targeting and increased intestinal barrier permeability in both cell and zebrafish xenotransplantation models. Furthermore, NCG showed liver targeting and enterohepatic circulation in mouse breast cancer xenografts following oral administration. Notably, the cancer inhibition efficacy of NCG was superior to that of both NAR and the positive control tamoxifen, and was accompanied by increased hepatic EST expression and reduced estradiol levels in the liver, blood, and tumor tissue. Moreover, few side effects were observed after NCG treatment. Our findings reveal NCG as a promising candidate for endocrine therapy and highlight hepatic EST targeting as a novel therapeutic strategy for HR+ breast cancer.


Assuntos
Neoplasias da Mama , Flavanonas , Nanopartículas , Humanos , Camundongos , Animais , Feminino , Neoplasias da Mama/patologia , Peixe-Zebra/metabolismo , Receptores de Estrogênio/metabolismo , Estrogênios/metabolismo , Estrogênios/uso terapêutico , Tamoxifeno/farmacologia , Estradiol/farmacologia , Fígado/metabolismo
18.
Ecotoxicol Environ Saf ; 272: 116035, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309234

RESUMO

A suspension of copper oxide nanoparticles (CuO NPs) is a mixture of dissolved and particulate Cu, the relative proportions of which highly depend on the water chemistry. However, the relationship between different proportions of particulate and dissolved Cu and the overall toxicity of CuO NPs is still unknown. This study investigated the response of Chlorella vulgaris to CuO NPs at varying solution pH and at different tannic acid (TA) additions, with a focus on exploring whether and how dissolved and particulate Cu contribute to the overall toxicity of CuO NPs. The results of the exposure experiments demonstrated the involvement of both dissolved and particulate Cu in inducing toxicity of CuO NPs, and the inhibition of CuO NPs on cell density of Chlorella vulgaris was found to be significantly (p < 0.05) alleviated with increased levels of TA and pH (< 8). Using the independent action model, the contribution to toxicity of particulate Cu was found to be enhanced with increasing pH values and TA concentrations. The toxic unit indicator better (R2 = 0.86, p < 0.001) explained impacts of CuO NPs on micro-algae cells than commonly used mass concentrations (R2 = 0.27-0.77, p < 0.05) across different levels of pH and TA. Overall, our study provides an additivity-based method to improve the accuracy of toxicity prediction through including contributions to toxicity of both dissolved and particulate Cu and through eliminating the uneven distribution of data due to large variations in total Cu, particulate Cu, dissolved Cu, Cu2+ activities, Cu-TA complexes and other Cu-complexes concentrations with varying water chemistry conditions.


Assuntos
Chlorella vulgaris , Nanopartículas Metálicas , Nanopartículas , Polifenóis , Cobre/toxicidade , Cobre/química , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Água , Concentração de Íons de Hidrogênio
19.
Chem Biodivers ; 21(5): e202301741, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38477870

RESUMO

Diabetes mellitus is an endocrine disease characterized by prolonged hyperglycemia. Prolonged high blood sugar levels interfere with the differentiation and maturation process of OBs and OCs, leading to the onset of osteoporosis. However, OCs differentiation and maturation is a complex regulatory process. In this study, we used a co-culture system of RAW264.7 and MC3T3-E1 cells under HG concentration to explore the effect of CYM on OCs in a HG environment. The effects of CYM on the formation and function of OCs were observed using TRAP-positive cell counts and bone resorption pits. Then, mRNA and protein expression levels of OCs-related genes were detected by real-time qPCR and western blotting. The results showed that CYM had an inhibitory effect on OCs differentiation and bone resorption, reduced mRNAs expression of OCs-associated genes, and downregulated RANKL/RANK/TRAF6 pathway that mediates OCs differentiation. CYM could be a promising natural compound against diabetic osteoporosis.


Assuntos
Diferenciação Celular , Glucose , Osteoclastos , Ligante RANK , Animais , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/citologia , Camundongos , Glucose/metabolismo , Glucose/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células RAW 264.7 , Ligante RANK/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Células Cultivadas , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/genética , Relação Dose-Resposta a Droga , Reabsorção Óssea/metabolismo , Reabsorção Óssea/tratamento farmacológico
20.
Aesthetic Plast Surg ; 48(11): 2034-2041, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38676769

RESUMO

BACKGROUND: As a rare auricular deformity, despite numerous surgical procedures for correcting moderate-to-severe question mark ears described in past studies, there remains a need to explore a more cost-effective approach. The optimal utilization of ear cartilage and surrounding skin while achieving superior outcomes continues to pose a significant challenge. METHODS: From 2018 to 2023, twenty-four patients with unilateral question mark ear were enrolled in this study. Seven of them were severe type deformities (absence of lower part of auricle), and seventeen were moderate (only cleft between helix and lobule). All patients were treated with new method using local cartilage and flap without damage in unaffected area. RESULTS: All patients were satisfied with significant improvement of question mark ear and the overall symmetrical appearance. The surgical scar was not obvious. No complications were observed. The follow-up period revealed that the corrective procedure kept producing the symmetrical and cosmetic results. CONCLUSION: Our new method enables optimal utilization of deformed tissue and surrounding skin, rendering this method effective and reliable for correcting moderate-to-severe question mark ears. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Cartilagem da Orelha , Estética , Procedimentos de Cirurgia Plástica , Retalhos Cirúrgicos , Humanos , Feminino , Retalhos Cirúrgicos/transplante , Masculino , Cartilagem da Orelha/cirurgia , Cartilagem da Orelha/transplante , Procedimentos de Cirurgia Plástica/métodos , Adulto Jovem , Adulto , Adolescente , Resultado do Tratamento , Estudos Retrospectivos , Estudos de Coortes , Seguimentos , Satisfação do Paciente/estatística & dados numéricos , Criança , Medição de Risco , Orelha Externa/cirurgia , Orelha Externa/anormalidades , Pavilhão Auricular/cirurgia , Pavilhão Auricular/anormalidades
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