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1.
Nat Chem Biol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773328

RESUMO

A timely inflammatory response is crucial for early viral defense, but uncontrolled inflammation harms the host. Retinoic acid-inducible gene I (RIG-I) has a pivotal role in detecting RNA viruses, yet the regulatory mechanisms governing its sensitivity remain elusive. Here we identify PTENα, an N-terminally extended form of PTEN, as an RNA-binding protein with a preference for the CAUC(G/U)UCAU motif. Using both in vivo and in vitro viral infection assays, we demonstrated that PTENα restricted the host innate immune response, relying on its RNA-binding capacity and phosphatase activity. Mechanistically, PTENα directly bound to viral RNA and enzymatically converted its 5'-triphosphate to 5'-monophosphate, thereby reducing RIG-I sensitivity. Physiologically, brain-intrinsic PTENα exerted protective effects against viral inflammation, while peripheral PTENα restricted host antiviral immunity and, to some extent, promoted viral replication. Collectively, our findings underscore the significance of PTENα in modulating viral RNA- and RIG-I-mediated immune recognition, offering potential therapeutic implications for infectious diseases.

2.
Nat Chem Biol ; 20(2): 201-210, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012344

RESUMO

Bacteria can be programmed to create engineered living materials (ELMs) with self-healing and evolvable functionalities. However, further development of ELMs is greatly hampered by the lack of engineerable nonpathogenic chassis and corresponding programmable endogenous biopolymers. Here, we describe a technological workflow for facilitating ELMs design by rationally integrating bioinformatics, structural biology and synthetic biology technologies. We first develop bioinformatics software, termed Bacteria Biopolymer Sniffer (BBSniffer), that allows fast mining of biopolymers and biopolymer-producing bacteria of interest. As a proof-of-principle study, using existing pathogenic pilus as input, we identify the covalently linked pili (CLP) biosynthetic gene cluster in the industrial workhorse Corynebacterium glutamicum. Genetic manipulation and structural characterization reveal the molecular mechanism of the CLP assembly, ultimately enabling a type of programmable pili for ELM design. Finally, engineering of the CLP-enabled living materials transforms cellulosic biomass into lycopene by coupling the extracellular and intracellular bioconversion ability.


Assuntos
Bactérias , Engenharia Metabólica , Fluxo de Trabalho , Licopeno , Biopolímeros
3.
Nature ; 586(7827): 80-86, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32717741

RESUMO

Tandem DNA repeats vary in the size and sequence of each unit (motif). When expanded, these tandem DNA repeats have been associated with more than 40 monogenic disorders1. Their involvement in disorders with complex genetics is largely unknown, as is the extent of their heterogeneity. Here we investigated the genome-wide characteristics of tandem repeats that had motifs with a length of 2-20 base pairs in 17,231 genomes of families containing individuals with autism spectrum disorder (ASD)2,3 and population control individuals4. We found extensive polymorphism in the size and sequence of motifs. Many of the tandem repeat loci that we detected correlated with cytogenetic fragile sites. At 2,588 loci, gene-associated expansions of tandem repeats that were rare among population control individuals were significantly more prevalent among individuals with ASD than their siblings without ASD, particularly in exons and near splice junctions, and in genes related to the development of the nervous system and cardiovascular system or muscle. Rare tandem repeat expansions had a prevalence of 23.3% in children with ASD compared with 20.7% in children without ASD, which suggests that tandem repeat expansions make a collective contribution to the risk of ASD of 2.6%. These rare tandem repeat expansions included previously undescribed ASD-linked expansions in DMPK and FXN, which are associated with neuromuscular conditions, and in previously unknown loci such as FGF14 and CACNB1. Rare tandem repeat expansions were associated with lower IQ and adaptive ability. Our results show that tandem DNA repeat expansions contribute strongly to the genetic aetiology and phenotypic complexity of ASD.


Assuntos
Transtorno do Espectro Autista/genética , Expansão das Repetições de DNA/genética , Genoma Humano/genética , Genômica , Sequências de Repetição em Tandem/genética , Feminino , Fatores de Crescimento de Fibroblastos/genética , Predisposição Genética para Doença , Humanos , Inteligência/genética , Proteínas de Ligação ao Ferro/genética , Masculino , Miotonina Proteína Quinase/genética , Motivos de Nucleotídeos , Polimorfismo Genético , Frataxina
4.
Nucleic Acids Res ; 52(6): 3213-3233, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38227555

RESUMO

N 6-Threonylcarbamoyladenosine at A37 (t6A37) of ANN-decoding transfer RNAs (tRNAs) is a universal modification whose functions have been well documented in bacteria and lower eukaryotes; however, its role in organellar translation is not completely understood. In this study, we deleted the mitochondrial t6A37-modifying enzyme OSGEPL1 in HEK293T cells. OSGEPL1 is dispensable for cell viability. t6A37 hypomodification selectively stimulated N1-methyladenosine at A9 (m1A9) and N2-methylguanosine at G10 (m2G10) modifications and caused a substantial reduction in the aminoacylation of mitochondrial tRNAThr and tRNALys, resulting in impaired translation efficiency. Multiple types of amino acid misincorporation due to the misreading of near-cognate codons by t6A37-unmodified tRNAs were detected, indicating a triggered translational infidelity. Accordingly, the alterations in mitochondrial structure, function, and the activated mitochondrial unfolded protein response were observed. Mitochondrial function was efficiently restored by wild-type, but not by tRNA-binding-defective OSGEPL1. Lastly, in Osgepl1 deletion mice, disruption to mitochondrial translation was evident but resulted in no observable deficiency under physiological conditions in heart, which displays the highest Osgepl1 expression. Taken together, our data delineate the multifaceted roles of mitochondrial t6A37 modification in translation efficiency and quality control in mitochondria.


Assuntos
Genes Mitocondriais , Mitocôndrias , RNA de Transferência , Animais , Humanos , Camundongos , Células HEK293 , Mitocôndrias/genética , Mitocôndrias/metabolismo , Biossíntese de Proteínas , RNA de Transferência/metabolismo
5.
Gastroenterology ; 167(2): 264-280, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38417530

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is characterized by an immune-suppressive microenvironment, which contributes to tumor progression, metastasis, and immunotherapy resistance. Identification of HCC-intrinsic factors regulating the immunosuppressive microenvironment is urgently needed. Here, we aimed to elucidate the role of SYR-Related High-Mobility Group Box 18 (SOX18) in inducing immunosuppression and to validate novel combination strategies for SOX18-mediated HCC progression and metastasis. METHODS: The role of SOX18 in HCC was investigated in orthotopic allografts and diethylinitrosamine/carbon tetrachloride-induced spontaneous models by using murine cell lines, adeno-associated virus 8, and hepatocyte-specific knockin and knockout mice. The immune cellular composition in the HCC microenvironment was evaluated by flow cytometry and immunofluorescence. RESULTS: SOX18 overexpression promoted the infiltration of tumor-associated macrophages (TAMs) and regulatory T cells (Tregs) while diminishing cytotoxic T cells to facilitate HCC progression and metastasis in cell-derived allografts and chemically induced HCC models. Mechanistically, transforming growth factor-beta 1 (TGF-ß1) upregulated SOX18 expression by activating the Smad2/3 complex. SOX18 transactivated chemokine (C-X-C motif) ligand 12 (CXCL12) and programmed death ligand 1 (PD-L1) to induce the immunosuppressive microenvironment. CXCL12 knockdown significantly attenuated SOX18-induced TAMs and Tregs accumulation and HCC dissemination. Antagonism of chemokine receptor 4 (CXCR4), the cognate receptor of CXCL12, or selective knockout of CXCR4 in TAMs or Tregs likewise abolished SOX18-mediated effects. TGFßR1 inhibitor Vactosertib or CXCR4 inhibitor AMD3100 in combination with anti-PD-L1 dramatically inhibited SOX18-mediated HCC progression and metastasis. CONCLUSIONS: SOX18 promoted the accumulation of immunosuppressive TAMs and Tregs in the microenvironment by transactivating CXCL12 and PD-L1. CXCR4 inhibitor or TGFßR1 inhibitor in synergy with anti-PD-L1 represented a promising combination strategy to suppress HCC progression and metastasis.


Assuntos
Antígeno B7-H1 , Benzilaminas , Carcinoma Hepatocelular , Quimiocina CXCL12 , Ciclamos , Progressão da Doença , Neoplasias Hepáticas , Receptores CXCR4 , Fatores de Transcrição SOXF , Linfócitos T Reguladores , Fator de Crescimento Transformador beta1 , Microambiente Tumoral , Macrófagos Associados a Tumor , Regulação para Cima , Animais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição SOXF/metabolismo , Fatores de Transcrição SOXF/genética , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Microambiente Tumoral/imunologia , Humanos , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Fator de Crescimento Transformador beta1/metabolismo , Camundongos , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/genética , Ciclamos/farmacologia , Benzilaminas/farmacologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linhagem Celular Tumoral , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia , Camundongos Knockout , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Camundongos Endogâmicos C57BL , Dietilnitrosamina/toxicidade , Masculino
6.
Plant Physiol ; 195(2): 1461-1474, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38431527

RESUMO

Black goji berry (Lycium ruthenicum Murray) contains a rich source of health-promoting anthocyanins which are used in herbal medicine and nutraceutical foods in China. A natural variant producing white berries allowed us to identify two key genes involved in the regulation of anthocyanin biosynthesis in goji berries: one encoding a MYB transcription factor (LrAN2-like) and one encoding a basic helix-loop-helix (bHLH) transcription factor (LrAN1b). We previously found that LrAN1b expression was lost in the white berry variant, but the molecular basis for this phenotype was unknown. Here, we identified the molecular mechanism for loss of anthocyanins in white goji berries. In white goji, the LrAN1b promoter region has a 229 bp deletion that removes three MYB-binding elements and one bHLH-binding element, which are key to its expression. Complementation of the white goji berry LrAN1b allele with the LrAN1b promoter restored pigmentation. Virus-induced gene silencing of LrAN1b in black goji berry reduced fruit anthocyanin biosynthesis. Molecular analyses showed that LrAN2-like and another bHLH transcription factor LrJAF13 can activate LrAN1b by binding directly to the MYB-recognizing element and bHLH-recognizing element of its promoter-deletion region. LrAN1b expression is enhanced by the interaction of LrAN2-like with LrJAF13 and the WD40 protein LrAN11. LrAN2-like and LrAN11 interact with either LrJAF13 or LrAN1b to form two MYB-bHLH-WD40 complexes, which hierarchically regulate anthocyanin biosynthesis in black goji berry. This study on a natural variant builds a comprehensive anthocyanin regulatory network that may be manipulated to tailor goji berry traits.


Assuntos
Antocianinas , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Frutas , Regulação da Expressão Gênica de Plantas , Lycium , Proteínas de Plantas , Regiões Promotoras Genéticas , Antocianinas/biossíntese , Antocianinas/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Frutas/genética , Frutas/metabolismo , Lycium/genética , Lycium/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Deleção de Sequência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Proc Natl Acad Sci U S A ; 119(49): e2206737119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442107

RESUMO

Orphan nuclear receptor Nurr1 plays important roles in the progression of various diseases, including Parkinson's disease, neuroinflammation, Alzheimer's disease, and multiple sclerosis. It can recognize DNA as a monomer or heterodimer with retinoid X receptor α (RXRα). But the molecular mechanism of its transcriptional activity regulation is still largely unknown. Here we obtained a crystal structure of monomer Nurr1 (DNA- and ligand-binding domains, DBD and LBD) bound to NGFI-B response element. The structure exhibited two different forms with distinct DBD orientations, unveiling the conformational flexibility of nuclear receptor monomer. We then generated an integrative model of Nurr1-RXRα heterodimer. In the context of heterodimer, the structural flexibility of Nurr1 would contribute to its transcriptional activity modulation. We demonstrated that the DNA sequence may specifically modulate the transcriptional activity of Nurr1 in the absence of RXRα agonist, but the modulation can be superseded when the agonist binds to RXRα. Together, we propose a set of signaling pathways for the constitutive transcriptional activation of Nurr1 and provide molecular mechanisms for therapeutic discovery targeting Nurr1 and Nurr1-RXRα heterodimer.


Assuntos
Elementos de Resposta , Receptor X Retinoide alfa , Ativação Transcricional , Receptor X Retinoide alfa/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Domínios Proteicos
8.
Nano Lett ; 24(5): 1717-1728, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38270376

RESUMO

Surgery is the primary method to treat malignant melanoma; however, the residual microtumors that cannot be resected completely often trigger tumor recurrence, causing tumor-related mortality following melanoma resection. Herein, we developed a feasible strategy based on the combinational chemoimmunotherapy by cross-linking carboxymethyl chitosan (CMCS)-originated polymetformin (PolyMetCMCS) with cystamine to prepare stimuli-responsive nanogel (PMNG) owing to the disulfide bond in cystamine that can be cleaved by the massive glutathione (GSH) in tumor sites. Then, chemotherapeutic agent doxorubicin (DOX) was loaded in PMNG, which was followed by a hyaluronic acid coating to improve the overall biocompatibility and targeting ability of the prepared nanogel (D@HPMNG). Notably, PMNG effectively reshaped the tumor immune microenvironment by reprogramming tumor-associated macrophage phenotypes and recruiting intratumoral CD8+ T cells owing to the inherited immunomodulatory capability of metformin. Consequently, D@HPMNG treatment remarkably suppressed melanoma growth and inhibited its recurrence after surgical resection, proposing a promising solution for overcoming lethal melanoma recurrence.


Assuntos
Melanoma , Polietilenoglicóis , Polietilenoimina , Humanos , Nanogéis , Macrófagos Associados a Tumor , Cistamina , Linfócitos T CD8-Positivos , Doxorrubicina , Glutationa/química , Microambiente Tumoral , Linhagem Celular Tumoral
9.
Nano Lett ; 24(22): 6767-6777, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38771956

RESUMO

Efforts to prolong the blood circulation time and bypass immune clearance play vital roles in improving the therapeutic efficacy of nanoparticles (NPs). Herein, a multifunctional nanoplatform (BPP@RTL) that precisely targets tumor cells is fabricated by encapsulating ultrasmall phototherapeutic agent black phosphorus quantum dot (BPQD), chemotherapeutic drug paclitaxel (PTX), and immunomodulator PolyMetformin (PM) in hybrid membrane-camouflaged liposomes. Specifically, the hybrid cell membrane coating derived from the fusion of cancer cell membrane and red blood cell membrane displays excellent tumor targeting efficiency and long blood circulation property due to the innate features of both membranes. After collaboration with aPD-L1-based immune checkpoint blockade therapy, a boosted immunotherapeutic effect is obtained due to elevated dendritic cell maturation and T cell activation. Significantly, laser-irradiated BPP@RTL combined with aPD-L1 effectively eliminates primary tumors and inhibits lung metastasis in 4T1 breast tumor model, offering a promising treatment plan to develop personalized antitumor strategy.


Assuntos
Imunoterapia , Paclitaxel , Fósforo , Pontos Quânticos , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Animais , Fósforo/química , Camundongos , Paclitaxel/química , Paclitaxel/uso terapêutico , Paclitaxel/farmacologia , Paclitaxel/administração & dosagem , Feminino , Humanos , Linhagem Celular Tumoral , Lipossomos/química , Nanopartículas/química , Camundongos Endogâmicos BALB C
10.
Am J Physiol Gastrointest Liver Physiol ; 326(4): G460-G472, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38440827

RESUMO

Current therapy for hepatic injury induced by the accumulation of bile acids is limited. Leucine-rich repeat G protein-coupled receptor 4 (LGR4), also known as GPR48, is critical for cytoprotection and cell proliferation. Here, we reported a novel function for the LGR4 in cholestatic liver injury. In the bile duct ligation (BDL)-induced liver injury model, hepatic LGR4 expression was significantly downregulated. Deficiency of LGR4 in hepatocytes (Lgr4LKO) notably decreased BDL-induced liver injury measured by hepatic necrosis, fibrosis, and circulating liver enzymes and total bilirubin. Levels of total bile acids in plasma and liver were markedly reduced in these mice. However, deficiency of LGR4 in macrophages (Lyz2-Lgr4MKO) demonstrated no significant effect on liver injury induced by BDL. Deficiency of LGR4 in hepatocytes significantly attenuated S1PR2 and the phosphorylation of protein kinase B (AKT) induced by BDL. Recombinant Rspo1 and Rspo3 potentiated the taurocholic acid (TCA)-induced upregulation in S1PR2 and phosphorylation of AKT in hepatocytes. Inhibition of S1PR2-AKT signaling by specific AKT or S1PR2 inhibitors blocked the increase of bile acid secretion induced by Rspo1/3 in hepatocytes. Our studies indicate that the R-spondins (Rspos)-LGR4 signaling in hepatocytes aggravates the cholestatic liver injury by potentiating the production of bile acids in a S1PR2-AKT-dependent manner.NEW & NOTEWORTHY Deficiency of LGR4 in hepatocytes alleviates BDL-induced liver injury. LGR4 in macrophages demonstrates no effect on BDL-induced liver injury. Rspos-LGR4 increases bile acid synthesis and transport via potentiating S1PR2-AKT signaling in hepatocytes.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Colestase , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fígado/metabolismo , Colestase/complicações , Colestase/metabolismo , Hepatócitos/metabolismo , Ácidos e Sais Biliares/metabolismo , Ductos Biliares/metabolismo , Ligadura , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
11.
Anal Chem ; 96(19): 7550-7557, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38706132

RESUMO

Developing precise tumor cell-specific mitochondrial ferroptosis-related inhibition miRNA imaging methods holds enormous potential for anticancer drug screening and cancer treatment. Nevertheless, traditional amplification methods still tolerated the limited tumor specificity because of the "off-tumor" signal leakage resulting from their "always-active" sensing mode. To overcome this limitation, we herein developed a dual (exogenous 808 nm NIR light and endogenous APE1) activated nanoladder for precise imaging of mitochondrial ferroptosis-related miRNA with tumor cell specificity and improved imaging resolution. Exogenous NIR light-activation can regulate the ferroptosis-related inhibition miRNA imaging signals within mitochondria, and endogenous enzyme-activation can confine signals to tumor cells. Based on this dual activation design, off-tumor signals were greatly reduced and tumor-to-background contrast was enhanced with an improved tumor/normal discrimination ratio, realizing tumor cell-specific precise imaging of mitochondrial ferroptosis-related inhibition miRNA.


Assuntos
Ferroptose , MicroRNAs , Mitocôndrias , Ferroptose/efeitos dos fármacos , Humanos , MicroRNAs/metabolismo , MicroRNAs/análise , Mitocôndrias/metabolismo , Animais , Camundongos , Imagem Óptica , Linhagem Celular Tumoral , Raios Infravermelhos , Nanopartículas/química
12.
Plant Biotechnol J ; 22(6): 1435-1452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38194521

RESUMO

Wolfberry is a plant with medicinal and food values. However, its bioactive ingredients and the corresponding genetic bases have not been determined. Here, we de novo generated a chromosome-level genome assembly for wolfberry, yielding a genome sequence of ~1.77 Gb with contig N50 of 50.55 Mb and 39 224 predicted gene models. A variation map, using 307 re-sequenced accessions, was called based on this genome assembly. Furthermore, the fruit metabolome of these accessions was profiled using 563 annotated metabolites, which separated Lycium barbarum L. and non-L. barbarum L. The flavonoids, coumarins, alkaloids and nicotinic acid contents were higher in the former than in the latter. A metabolite-based genome-wide association study mapped 156 164 significant single nucleotide polymorphisms corresponding to 340 metabolites. This included 19 219 unique lead single nucleotide polymorphisms in 1517 significant association loci, of which three metabolites, flavonoids, betaine and spermidine, were highlighted. Two candidate genes, LbUGT (evm.TU.chr07.2692) and LbCHS (evm.TU.chr07.2738), with non-synonymous mutations, were associated with the flavonoids content. LbCHS is a structural gene that interacts with a nearby MYB transcription factor (evm.TU.chr07.2726) both in L. barbarum and L. ruthenicum. Thus, these three genes might be involved in the biosynthesis/metabolism of flavonoids. LbSSADH (evm.TU.chr09.627) was identified as possibly participating in betaine biosynthesis/metabolism. Four lycibarbarspermidines (E-G and O) were identified, and only the lycibarbarspermidines O content was higher in L. barbarum varieties than in non-L. barbarum varieties. The evm.TU.chr07.2680 gene associated with lycibarbarspermidines O was annotated as an acetyl-CoA-benzylalcohol acetyltransferase, suggesting that it is a candidate gene for spermidine biosynthesis. These results provide novel insights into the specific metabolite profile of non-L. barbarum L. and the genetic bases of flavonoids, betaine and spermidine biosynthesis/metabolism.


Assuntos
Betaína , Flavonoides , Estudo de Associação Genômica Ampla , Lycium , Polimorfismo de Nucleotídeo Único , Espermidina , Flavonoides/metabolismo , Lycium/genética , Lycium/metabolismo , Espermidina/metabolismo , Betaína/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Genoma de Planta/genética , Frutas/genética , Frutas/metabolismo
13.
FASEB J ; 37(4): e22831, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36856728

RESUMO

The metabolic benefits of intermittent fasting (IF) have been well recognized. However, limited studies have examined the relationship between long-term maternal IF before pregnancy and offspring health. In this study, a C57BL/6J mouse model of long-term IF before pregnancy was established: 4-week-old female mice were subjected to alternate-day fasting for 12 weeks and resumed normal diet after mating. Female mice in the control group were fed ad libitum. Offspring mice were weaned at 6 weeks of age and fed a normal chow diet or a 60% high-fat diet. The effects of long-term pre-pregnancy IF on offspring metabolism and its underlying mechanism were examined. We found that neonatal IF offspring weighted significantly less relevant to control mice. This difference gradually disappeared as a result of catch-up growth. In the IF offspring, adipose tissue mass was significantly increased. This alteration was associated with a considerable deterioration in glucose tolerance. No significant difference in food intake was observed. Further, lipid deposition as well as triglyceride contents in the liver were greatly increased. Maternal IF significantly decreased levels of DNA methyltransferase in the liver of offspring. DNA methylation modifications of molecules associated with the mTORC1 signaling pathway were significantly altered, leading to the significant inhibition of mTORC1 signaling. Overexpression of S6K1 activated hepatic mTORC1 signaling and reversed the metabolic dysfunction in IF offspring. In conclusion, long-term pre-pregnancy IF increases hepatic steatosis and adiposity, as well as impairs glucose metabolism in adult offspring. This occurs through DNA methylation-dependent suppression of hepatic mTORC1 signaling activity.


Assuntos
Fígado Gorduroso , Jejum Intermitente , Feminino , Gravidez , Animais , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
14.
Langmuir ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990344

RESUMO

The size or the curvature of nanoparticles (NPs) plays an important role in regulating the composition of the protein corona. However, the molecular mechanisms of how curvature affects the interaction of NPs with serum proteins still remain elusive. In this study, we employ all-atom molecular dynamics simulations to investigate the interactions between two typical serum proteins and PEGylated Au NPs with three different surface curvatures (0, 0.1, and 0.5 nm-1, respectively). The results show that for proteins with a regular shape, the binding strength between the serum protein and Au NPs decreases with increasing curvature. For irregularly shaped proteins with noticeable grooves, the binding strength between the protein and Au NPs does not change obviously with increasing curvature in the cases of smaller curvature. However, as the curvature continues to increase, Au NPs may act as ligands firmly adsorbed in the protein grooves, significantly enhancing the binding strength. Overall, our findings suggest that the impact of NP curvature on protein adsorption may be nonmonotonic, which may provide useful guidelines for better design of functionalized NPs in biomedical applications.

15.
Langmuir ; 40(2): 1295-1304, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38173387

RESUMO

The fluorinated decorations have recently been widely used in many biomedical applications. However, the potential mechanism of the fluorination effect on the cellular delivery of nanoparticles (NPs) still remains elusive. In this work, we systemically explore the penetration of a perfluoro-octanethiol-coated gold NP (PF-Au NP) and, for comparison, an octanethiol-coated gold NP (OT-Au NP) across lipid bilayers. We also investigated the effect of these two types of NPs on the properties of lipid bilayers. Our findings indicate that the lipid type and the surface tension of the lipid bilayer significantly impact the penetration capabilities of the fluorinated gold NP. By examining the distribution of ligands on the surface of the two types of NPs in water and during the penetration process, we unveil their distinct penetration characteristics. Specifically, the PF-Au NP exhibits amphiphobic behavior (both hydrophobic and lipophobic), while the OT-Au NP exhibits solely hydrophobic characteristics. Finally, we observe that the penetration capabilities can be increased by adjusting the degree of fluorination of the ligands on the NP surface. Overall, this study provides useful physical insights into the unique properties of the fluorinated decorations in NP permeation.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Bicamadas Lipídicas/química , Halogenação , Nanopartículas Metálicas/química , Nanopartículas/química , Modelos Moleculares , Ouro/química , Ligantes
16.
Gynecol Oncol ; 187: 58-63, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38733953

RESUMO

OBJECTIVES: To evaluate the impact of high-potency topical steroid use on risk of recurrence of lichen sclerosus-associated vulvar cancer. METHODS: This is a retrospective cohort study evaluating patients with lichen sclerosus (LS)- associated vulvar squamous cell cancer (VSCC). Demographic and clinical outcome data were compared between two comparison groups: patients who received steroids, mainly clobetasol, and patients who did not receive steroids following treatment of LS-related vulvar cancer. Categorical variables were compared using Fisher's exact test or chi-square test. Continuous variables were compared using a two-sided student's t-test. Time to recurrence (TTR) and overall survival (OS) were analyzed using Kaplan-Meier survival plot and compared using Mantel-Cox log rank test. Cox proportional hazard regression models were conducted to generate hazard ratios for both TTR and OS. A p value of <0.05 was considered statistically significant. RESULTS: A total of 49 patients were included, with 36 patients receiving steroid treatment and 13 patients in the expectant management group. The median age of diagnosis was 68. The average BMI was 31.7 +/- 7.0. The median length of follow up was 41 months. The majority of patients were diagnosed with stage I VSCC. There was no difference in demographics or oncologic management of vulvar cancer between the two cohorts. Overall recurrence was decreased among patients who received steroid treatment when compared to patients who did not, 12 patients (33.3%) versus 9 patients (69.2%) respectively (p = 0.048). CONCLUSIONS: High-potency topical steroid use following treatment of lichen sclerosus-associated vulvar squamous cell carcinoma is associated with decreased risk of recurrence and prolonged median time to recurrence.

17.
J Periodontal Res ; 59(1): 119-127, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37817319

RESUMO

BACKGROUND: Toll-like receptor 4 (TLR4)-mediated inflammatory responses are associated with diabetes and periodontitis, which are dysregulated by O-GlcNAcylation. OBJECTIVE: This study aimed to investigate the effects of O-GlcNAc transferase (OGT)-mediated TLR4 O-GlcNAcylation on the osteogenesis of periodontal ligament stem cells (PDLCs). METHODS: PDLCs were treated with high glucose (HG) to establish a cell model. Osteogenic differentiation was evaluated using western blotting, an alkaline phosphatase activity assay, and an alizarin red S staining assay. The regulation of OGT on the O-GlcNAcylation of TLR4 was analyzed using co-immunoprecipitation, immunoprecipitation, western blotting, and immunofluorescence staining. RESULTS: The results showed that HG inhibited osteogenic differentiation and promoted inflammatory response. Knockdown of OGT promoted osteogenic differentiation of HG-treated PDLCs. OGT interacted with TLR4 and increased the O-GlcNAcylation and protein levels of TLR4 in the cytomembrane of PDLCs. Moreover, silenced TLR4 reversed the effects on osteogenic differentiation induced by OGT in HG-treated PDLCs. CONCLUSION: O-GlcNAcylation of TLR4 induced by OGT suppresses osteogenic differentiation of PDLCs after HG stimulation. The findings suggest a promising strategy for treating DP.


Assuntos
Osteogênese , Receptor 4 Toll-Like , Receptor 4 Toll-Like/metabolismo , Ligamento Periodontal , Células Cultivadas , Diferenciação Celular , Células-Tronco
18.
Int J Equity Health ; 23(1): 97, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38735959

RESUMO

BACKGROUND: Unequal access to primary healthcare (PHC) has become a critical issue in global health inequalities, requiring governments to implement policies tailored to communities' needs and abilities. However, the place-based facility dimension of PHCs is oversimplified in current healthcare literature, and formulating the equity-oriented PHC spatial planning remains challenging without understanding the multiple impacts of community socio-spatial dynamics, particularly in remote areas. This study aims to push the boundary of PHC studies one step further by presenting a nuanced and dynamic understanding of the impact of community environments on the uneven primary healthcare supply. METHODS: Focusing on Shuicheng, a remote rural area in southwestern China, multiple data are included in this village-based study, i.e., the facility-level healthcare statistics data (2016-2019), the statistical yearbooks, WorldPop, and Chinese GDP's spatial distribution data. We evaluate villages' PHC service capacity using the number of doctors and essential equipment per capita, which are the major components of China's PHC delivery. The indicators describing community environments are selected based on extant literature and China's planning paradigms, including town- and village-level factors. Gini coefficients and local spatial autocorrelation analysis are used to present the divergences of PHC capacity, and multilevel regression model and (heterogeneous) difference in difference model are used to examine the driving role of community environments and the dynamics under the policy intervention. RESULTS: Despite the general improvement, PHC inequalities remain significant in remote rural areas. The village's location, aging, topography, ethnic autonomy, and economic conditions significantly influence village-level PHC capacity, while demographic characteristics and healthcare delivery at the town level are also important. Although it may improve the hardware setting in village clinics (coef. = 0.350), the recent equity-oriented policy attempts may accelerate the loss of rural doctors (coef. = - 0.517). Notably, the associations between PHC and community environments are affected inconsistently by this round of policy intervention. The town healthcare centers with higher inpatient service capacity (coef. = - 0.514) and more licensed doctors (coef. = - 0.587) and nurses (coef. = - 0.344) may indicate more detrimental policy effects that reduced the number of rural doctors, while the centers with more professional equipment (coef. = 0.504) and nurses (coef. = 0.184) are beneficial for the improvement of hardware setting in clinics. CONCLUSIONS: The findings suggest that the PHC inequalities are increasingly a result of joint social, economic, and institutional forces in recent years, underlining the increased complexity of the PHC resource allocation mechanism. Therefore, we claim the necessity to incorporate a broader understanding of community orientation in PHC delivery, particularly the interdisciplinary knowledge of the spatial lens of community, to support its sustainable development. Our findings also provide timely policy insights for ongoing primary healthcare reform in China.


Assuntos
Acessibilidade aos Serviços de Saúde , Atenção Primária à Saúde , Serviços de Saúde Rural , População Rural , China , Humanos , Atenção Primária à Saúde/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , População Rural/estatística & dados numéricos , Serviços de Saúde Rural/estatística & dados numéricos , Política de Saúde , Médicos/provisão & distribuição , Médicos/estatística & dados numéricos , Disparidades em Assistência à Saúde , Equipamentos e Provisões/provisão & distribuição
19.
Mol Biol Rep ; 51(1): 245, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300325

RESUMO

Nucleotide biosynthesis encompasses both de novo and salvage synthesis pathways, each characterized by significant material and procedural distinctions. Despite these differences, cells with elevated nucleotide demands exhibit a preference for the more intricate de novo synthesis pathway, intricately linked to modes of enzyme regulation. In this study, we primarily scrutinize the biological importance of a conserved yet promising mode of enzyme regulation in nucleotide metabolism-cytoophidia. Cytoophidia, comprising cytidine triphosphate synthase or inosine monophosphate dehydrogenase, is explored across diverse biological models, including yeasts, Drosophila, mice, and human cancer cell lines. Additionally, we delineate potential biomedical applications of cytoophidia. As our understanding of cytoophidia deepens, the roles of enzyme compartmentalization and polymerization in various biochemical processes will unveil, promising profound impacts on both research and the treatment of metabolism-related diseases.


Assuntos
Fenômenos Bioquímicos , Drosophila , Humanos , Animais , Camundongos , Linhagem Celular , Modelos Biológicos , Nucleotídeos
20.
Cereb Cortex ; 33(8): 4977-4989, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36227200

RESUMO

Autism is often comorbid with other psychiatric disorders. We have previously shown that Dip2a knockout (KO) induces autism-like behaviors in mice. However, the role of Dip2a in other psychiatric disorders remains unclear. In this paper, we revealed that Dip2a KO mice had comorbid anxiety. Dip2a KO led to a reduction in the dendritic length of cortical and hippocampal excitatory neurons. Molecular mechanism studies suggested that AMPK was overactivated and suppressed the mTOR cascade, contributing to defects in dendritic morphology. Deletion of Dip2a in adult-born hippocampal neurons (Dip2a conditional knockout (cKO)) increased susceptibility to anxiety upon acute stress exposure. Application of (2R,6R)-hydroxynorketamine (HNK), an inhibitor of mTOR, rescued anxiety-like behaviors in Dip2a KO and Dip2a cKO mice. In addition, 6 weeks of high-fat diet intake alleviated AMPK-mTOR signaling and attenuated the severity of anxiety in both Dip2a KO mice and Dip2a cKO mice. Taken together, these results reveal an unrecognized function of DIP2A in anxiety pathophysiology via regulation of AMPK-mTOR signaling.


Assuntos
Proteínas Quinases Ativadas por AMP , Transdução de Sinais , Camundongos , Animais , Camundongos Knockout , Serina-Treonina Quinases TOR/metabolismo , Ansiedade/genética , Proteínas Nucleares
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