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1.
J Environ Sci (China) ; 150: 1-13, 2025 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39306387

RESUMO

Iron oxide nanoparticles (IONPs) have wide applications in the biomedical field due to their outstanding physical and chemical properties. However, the potential adverse effects and related mechanisms of IONPs in human organs, especially the lung, are still largely ignored. In this study, we found that group-modified IONPs (carboxylated, aminated and silica coated) induce slight lung cell damage (in terms of the cell cycle, reactive oxygen species (ROS) production, cell membrane integrity and DNA damage) at a sublethal dosage. However, aminated IONPs could release more iron ions in the lysosome than the other two types of IONPs, but the abnormally elevated iron ion concentration did not induce ferroptosis. Intriguingly, amino-modified IONPs aggravated the accumulation of intracellular peroxides induced by the ferroptosis activator RSL3 and thus caused ferroptosis in vitro, and the coadministration of amino-modified IONPs and RSL3 induced more severe lung injury in vivo. Therefore, our data revealed that the surface functionalization of IONPs plays an important role in determining their potential pulmonary toxicity, as surface modification influences their degradation behavior. These results provide guidance for the design of future IONPs and the corresponding safety evaluations and predictions.


Assuntos
Ferroptose , Ferro , Lisossomos , Ferroptose/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/efeitos dos fármacos , Ferro/química , Humanos , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro/toxicidade , Morte Celular/efeitos dos fármacos
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 125011, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39213831

RESUMO

Thiols function as antioxidants in food, prolonging shelf life and enhancing flavor. Moreover, thiols are vital biomolecules involved in enzyme activity, cellular signal transduction, and protein folding among critical biological processes. In this paper, the fluorescent probe PYL-NBD was designed and synthesized, which utilized the fluorescent molecule pyrazoline, the lysosome-targeted morpholine moiety, and the sensing moiety NBD. Probe PYL-NBD was tailored for the recognition of biothiols through single-wavelength excitation, yielding distinct fluorescence emission signals: blue for Cys, Hcy, and GSH; green for Cys, Hcy. Probe PYL-NBD exhibited rapid reaction kinetics (<10 min), distinct fluorescence response signals, and low detection limits (15.7 nM for Cys, 14.4 nM for Hcy, and 12.6 nM for GSH). Probe PYL-NBD enabled quantitative determination of Cys content in food samples and L-cysteine capsules. Furthermore, probe PYL-NBD had been successfully applied for confocal imaging with dual-channel detection of biothiols in various biological specimens, including HeLa cells, zebrafish, tumor sections, and Arabidopsis thaliana.


Assuntos
Cisteína , Corantes Fluorescentes , Análise de Alimentos , Glutationa , Lisossomos , Espectrometria de Fluorescência , Peixe-Zebra , Humanos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Lisossomos/química , Lisossomos/metabolismo , Células HeLa , Cisteína/análise , Animais , Análise de Alimentos/métodos , Glutationa/análise , Espectrometria de Fluorescência/métodos , Homocisteína/análise , Arabidopsis/química , Limite de Detecção , Microscopia Confocal
3.
Phytomedicine ; 134: 155958, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39241385

RESUMO

BACKGROUND: Maintaining intracellular equilibrium is essential for the viability of tumor cells, which tend to be particularly vulnerable to environmental stressors. Consequently, targeting the disruption of this homeostasis offers a promising approach for oncological treatments. LW-213, a novel derivative of wogonin, effectively induces apoptosis in cancer cells by initiating endoplasmic reticulum (ER) stress, although the precise molecular pathways involved remain intricate and multifaceted. PURPOSE: This research aimed to explore how LW-213 prompts apoptosis in non-small cell lung cancer (NSCLC) cells and to clarify the detailed mechanisms that govern this process. METHODS: Various NSCLC cell lines were utilized to delineate the apoptotic effects induced by LW-213. Advanced methodologies, including RNA sequencing (RNA-seq), Western blotting (WB), immunofluorescence (IF), immunoprecipitation (IP), flow cytometry (Fc), real-time quantitative polymerase chain reaction (RT-qPCR), and electron microscopy, were employed to investigate the underlying molecular interactions. The efficacy and mechanistic action of LW-213 were also assessed in a xenograft model using nude mice. RESULTS: We demonstrated that LW-213, a small molecule cationic amphiphilic drug (CAD), inhibited Niemann-Pick C1 (NPC1) function and induced lysosomal membrane damage, thereby activating the phosphoinositide-initiated membrane tethering and lipid transport (PITT) pathway. This activation promoted cholesterol transport from the ER to the lysosome, perpetuating a cholesterol-deficient state in the ER, including massive exocytosis of Ca2+ and activation of FAM134B-mediated reticulophagy. Ultimately, excessive reticulophagy induced lethal ER stress. CONCLUSIONS: In summary, our study elucidates an organelle domino reaction initiated by lysosome damage and a series of self-rescue mechanisms that eventually lead to irreversible lethal effects, revealing a potential drug intervention strategy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Estresse do Retículo Endoplasmático , Flavanonas , Neoplasias Pulmonares , Lisossomos , Camundongos Nus , Humanos , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Flavanonas/farmacologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Camundongos , Apoptose/efeitos dos fármacos , Proteína C1 de Niemann-Pick , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto , Autofagia/efeitos dos fármacos , Flavonoides
4.
J Cell Biol ; 223(11)2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39283311

RESUMO

Autophagy plays a crucial role in cancer cell survival by facilitating the elimination of detrimental cellular components and the recycling of nutrients. Understanding the molecular regulation of autophagy is critical for developing interventional approaches for cancer therapy. In this study, we report that migfilin, a focal adhesion protein, plays a novel role in promoting autophagy by increasing autophagosome-lysosome fusion. We found that migfilin is associated with SNAP29 and Vamp8, thereby facilitating Stx17-SNAP29-Vamp8 SNARE complex assembly. Depletion of migfilin disrupted the formation of the SNAP29-mediated SNARE complex, which consequently blocked the autophagosome-lysosome fusion, ultimately suppressing cancer cell growth. Restoration of the SNARE complex formation rescued migfilin-deficiency-induced autophagic flux defects. Finally, we found depletion of migfilin inhibited cancer cell proliferation. SNARE complex reassembly successfully reversed migfilin-deficiency-induced inhibition of cancer cell growth. Taken together, our study uncovers a new function of migfilin as an autophagy-regulatory protein and suggests that targeting the migfilin-SNARE assembly could provide a promising therapeutic approach to alleviate cancer progression.


Assuntos
Autofagia , Moléculas de Adesão Celular , Proliferação de Células , Lisossomos , Proteínas Qb-SNARE , Proteínas Qc-SNARE , Proteínas R-SNARE , Humanos , Proteínas R-SNARE/metabolismo , Proteínas R-SNARE/genética , Proteínas Qb-SNARE/metabolismo , Proteínas Qb-SNARE/genética , Proteínas Qc-SNARE/metabolismo , Proteínas Qc-SNARE/genética , Lisossomos/metabolismo , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Autofagossomos/metabolismo , Células HeLa , Linhagem Celular Tumoral , Ligação Proteica , Proteínas SNARE/metabolismo , Proteínas SNARE/genética , Fusão de Membrana , Proteínas Qa-SNARE
5.
Nat Commun ; 15(1): 8132, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284802

RESUMO

Mucopolysaccharidoses are inherited metabolic disorders caused by the deficiency in lysosomal enzymes required to break down glycosaminoglycans. Accumulation of glycosaminoglycans leads to progressive, systemic degenerative disease. The central nervous system is particularly affected, resulting in developmental delays, neurological regression, and early mortality. Current treatments fail to adequately address neurological defects. Here we explore the potential of human induced pluripotent stem cell (hiPSC)-derived microglia progenitors as a one-time, allogeneic off-the-shelf cell therapy for several mucopolysaccharidoses (MPS). We show that hiPSC-derived microglia progenitors, possessing normal levels of lysosomal enzymes, can deliver functional enzymes into four subtypes of MPS knockout cell lines through mannose-6-phosphate receptor-mediated endocytosis in vitro. Additionally, our findings indicate that a single administration of hiPSC-derived microglia progenitors can reduce toxic glycosaminoglycan accumulation and prevent behavioral deficits in two different animal models of MPS. Durable efficacy is observed for eight months after transplantation. These results suggest a potential avenue for treating MPS with hiPSC-derived microglia progenitors.


Assuntos
Modelos Animais de Doenças , Glicosaminoglicanos , Células-Tronco Pluripotentes Induzidas , Microglia , Mucopolissacaridoses , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Animais , Microglia/metabolismo , Humanos , Mucopolissacaridoses/terapia , Camundongos , Glicosaminoglicanos/metabolismo , Camundongos Knockout , Diferenciação Celular , Transplante de Células-Tronco/métodos , Lisossomos/metabolismo
6.
Nat Commun ; 15(1): 8158, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289367

RESUMO

The neurovascular unit (NVU) is a complex multicellular structure that helps maintain cerebral homeostasis and blood-brain barrier (BBB) integrity. While extensive evidence links NVU alterations to cerebrovascular diseases and neurodegeneration, the underlying molecular mechanisms remain unclear. Here, we use zebrafish embryos carrying a mutation in Scavenger Receptor B2, a highly conserved endolysosomal protein expressed predominantly in Radial Glia Cells (RGCs), to investigate the interplay among different NVU components. Through live imaging and genetic manipulations, we demonstrate that compromised acidification of the endolysosomal compartment in mutant RGCs leads to impaired Notch3 signaling, thereby inducing excessive neurogenesis and reduced glial differentiation. We further demonstrate that alterations to the neuron/glia balance result in impaired VEGF and Wnt signaling, leading to severe vascular defects, hemorrhages, and a leaky BBB. Altogether, our findings provide insights into NVU formation and function and offer avenues for investigating diseases involving white matter defects and vascular abnormalities.


Assuntos
Barreira Hematoencefálica , Lisossomos , Neurogênese , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Lisossomos/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Células Ependimogliais/metabolismo , Células Ependimogliais/patologia , Endossomos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Receptores Notch/metabolismo , Receptores Notch/genética , Neuroglia/metabolismo , Neuroglia/patologia , Diferenciação Celular , Células-Tronco/metabolismo , Via de Sinalização Wnt , Mutação , Neovascularização Fisiológica , Animais Geneticamente Modificados , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/irrigação sanguínea , Transdução de Sinais , Angiogênese
7.
Gut Microbes ; 16(1): 2400575, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39312647

RESUMO

Enteropathogenic E. coli (EPEC) is a Gram-negative bacterial pathogen that causes persistent diarrhea. Upon attachment to the apical plasma membrane of the intestinal epithelium, the pathogen translocates virulence proteins called effectors into the infected cells. These effectors hijack numerous host processes for the pathogen's benefit. Therefore, studying the mechanisms underlying their action is crucial for a better understanding of the disease. We show that translocated EspH interacts with multiple host Rab GTPases. AlphaFold predictions and site-directed mutagenesis identified glutamic acid and lysine at positions 37 and 41 as Rab interacting residues in EspH. Mutating these sites abolished the ability of EspH to inhibit Akt and mTORC1 signaling, lysosomal exocytosis, and bacterial invasion. Knocking out the endogenous Rab8a gene expression highlighted the involvement of Rab8a in Akt/mTORC1 signaling and lysosomal exocytosis. A phosphoinositide binding domain with a critical tyrosine was identified in EspH. Mutating the tyrosine abolished the localization of EspH at infection sites and its capacity to interact with the Rabs. Our data suggest novel EspH-dependent mechanisms that elicit immune signaling and membrane trafficking during EPEC infection.


Assuntos
Membrana Celular , Escherichia coli Enteropatogênica , Proteínas rab de Ligação ao GTP , Humanos , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , Membrana Celular/metabolismo , Escherichia coli Enteropatogênica/metabolismo , Escherichia coli Enteropatogênica/genética , Fosfatidilinositóis/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/metabolismo , Ligação Proteica , Lisossomos/metabolismo , Transdução de Sinais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Exocitose , Interações Hospedeiro-Patógeno , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética
8.
J Cell Biol ; 223(11)2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39325073

RESUMO

Deleterious mutations in the lipopolysaccharide responsive beige-like anchor protein (LRBA) gene cause severe childhood immune dysregulation. The complexity of the symptoms involving multiple organs and the broad range of unpredictable clinical manifestations of LRBA deficiency complicate the choice of therapeutic interventions. Although LRBA has been linked to Rab11-dependent trafficking of the immune checkpoint protein CTLA-4, its precise cellular role remains elusive. We show that LRBA, however, only slightly colocalizes with Rab11. Instead, LRBA is recruited by members of the small GTPase Arf protein family to the TGN and to Rab4+ endosomes, where it controls intracellular traffic. In patient-derived fibroblasts, loss of LRBA led to defects in the endosomal pathway promoting the accumulation of enlarged endolysosomes and lysosome secretion. Thus, LRBA appears to regulate flow through the endosomal system on Rab4+ endosomes. Our data strongly suggest functions of LRBA beyond CTLA-4 trafficking and provide a conceptual framework to develop new therapies for LRBA deficiency.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Endossomos , Homeostase , Lisossomos , Proteínas rab de Ligação ao GTP , Proteínas rab4 de Ligação ao GTP , Humanos , Endossomos/metabolismo , Lisossomos/metabolismo , Proteínas rab4 de Ligação ao GTP/metabolismo , Proteínas rab4 de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Transporte Proteico , Fibroblastos/metabolismo , Fatores de Ribosilação do ADP/metabolismo , Fatores de Ribosilação do ADP/genética , Rede trans-Golgi/metabolismo , Células HeLa , Células HEK293 , Fator 1 de Ribosilação do ADP
9.
J Med Chem ; 67(18): 16899-16911, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39253767

RESUMO

The overexpression of NEU1 has recently been certified as being associated with myocardial infarction. However, the pursuit of an efficacious human NEU1 (hNEU1) inhibitor remains challenging, and viral NEU1 (viNEU1) inhibitor drugs are significantly weaker in terms of hNEU1 inhibition. Recognizing that hNEU1 is located within the lysosome, we designed a series of lysosome-targeting compounds, derived from oseltamivir, aimed at hNEU1 inhibition. Among these compounds, OsMo exhibits the most potent activity. Our findings reveal that OsMo accumulates within lysosomes and releases its pharmacophore via enzymatic catalysis. OsMo enhances hNEU1 inhibition by accumulating pharmacophores at the target site. OsMo exhibits improved regulation of abnormal autophagy during myocardial injury, demonstrating superior efficacy in treating myocardial infarction in vivo. Furthermore, OsMo exhibits acceptable pharmacokinetic parameters. Importantly, the development of molecules with lysosome-targeting abilities represents a promising avenue for addressing myocardial injuries linked to hNEU1 overexpression.


Assuntos
Lisossomos , Infarto do Miocárdio , Lisossomos/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Humanos , Animais , Camundongos , Masculino , Relação Estrutura-Atividade , Autofagia/efeitos dos fármacos
10.
STAR Protoc ; 5(3): 103309, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39269898

RESUMO

Lysosomal function and activity are essential to support cellular adaptation to multiple stresses. For example, certain drugs can induce increased lysosomal membrane permeability to exert their anti-cancer effects. Here, we present a protocol to evaluate the lysosome alterations induced by drug treatment. We first describe the steps for inducing lysosomal alterations in cultured cells. We then show how to quantify the number of lysosomes, assess the integrity of lysosomal membranes, and determine lysosomal membrane permeabilization by using galectin puncta assay. For complete details on the use and execution of this protocol, please refer to Jiang et al.1.


Assuntos
Permeabilidade da Membrana Celular , Leucemia Mieloide Aguda , Lisossomos , Lisossomos/metabolismo , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Membranas Intracelulares/metabolismo
11.
Nat Commun ; 15(1): 8334, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333072

RESUMO

Autophagy, a highly conserved self-digestion process crucial for cellular homeostasis, is triggered by various environmental signals, including nutrient scarcity. The regulation of lysosomal and autophagy-related processes is pivotal to maintaining cellular homeostasis and basal metabolism. The consequences of disrupting or diminishing lysosomal and autophagy systems have been investigated; however, information on the implications of hyperactivating lysosomal and autophagy genes on homeostasis is limited. Here, we present a mechanism of transcriptional repression involving upstream stimulatory factor 2 (USF2), which inhibits lysosomal and autophagy genes under nutrient-rich conditions. We find that USF2, together with HDAC1, binds to the CLEAR motif within lysosomal genes, thereby diminishing histone H3K27 acetylation, restricting chromatin accessibility, and downregulating lysosomal gene expression. Under starvation, USF2 competes with transcription factor EB (TFEB), a master transcriptional activator of lysosomal and autophagy genes, to bind to target gene promoters in a phosphorylation-dependent manner. The GSK3ß-mediated phosphorylation of the USF2 S155 site governs USF2 DNA-binding activity, which is involved in lysosomal gene repression. These findings have potential applications in the treatment of protein aggregation-associated diseases, including α1-antitrypsin deficiency. Notably, USF2 repression is a promising therapeutic strategy for lysosomal and autophagy-related diseases.


Assuntos
Autofagia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Lisossomos , Fatores Estimuladores Upstream , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Lisossomos/metabolismo , Autofagia/genética , Humanos , Fatores Estimuladores Upstream/metabolismo , Fatores Estimuladores Upstream/genética , Fosforilação , Histona Desacetilase 1/metabolismo , Histona Desacetilase 1/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Células HEK293 , Animais , Histonas/metabolismo , Células HeLa , Camundongos , Acetilação
12.
Nat Commun ; 15(1): 8318, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333495

RESUMO

Autoimmune attack toward pancreatic ß cells causes permanent loss of glucose homeostasis in type 1 diabetes (T1D). Insulin secretory granules store and secrete insulin but are also thought to be tissue messengers for T1D. Here, we show that the crinophagic granules (crinosome), a minor set of vesicles formed by fusing lysosomes with the conventional insulin dense-core granules (DCG), are pathogenic in T1D development in mouse models. Pharmacological inhibition of crinosome formation in ß cells delays T1D progression without affecting the dominant DCGs. Mechanistically, crinophagy inhibition diminishes the epitope repertoire in pancreatic islets, including cryptic, modified and disease-relevant epitopes derived from insulin. These unconventional insulin epitopes are largely undetectable in the MHC-II epitope repertoire of the thymus, where only canonical insulin epitopes are presented. CD4+ T cells targeting unconventional insulin epitopes display autoreactive phenotypes, unlike tolerized T cells recognizing epitopes presented in the thymus. Thus, the crinophagic pathway emerges as a tissue-intrinsic mechanism that transforms insulin from a signature thymic self-protein to a critical autoantigen by creating a peripheral-thymic mismatch in the epitope repertoire.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Insulina , Animais , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Camundongos , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Insulina/imunologia , Epitopos/imunologia , Linfócitos T CD4-Positivos/imunologia , Vesículas Secretórias/metabolismo , Vesículas Secretórias/imunologia , Camundongos Endogâmicos NOD , Autoantígenos/imunologia , Autoantígenos/metabolismo , Feminino , Modelos Animais de Doenças , Timo/imunologia , Humanos , Lisossomos/metabolismo , Lisossomos/imunologia
13.
Cancer Med ; 13(18): e70238, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39320136

RESUMO

BACKGROUND: Lysosomal dysfunction (LD) impacts cytokine regulation, inflammation, and immune responses, influencing the development and progression of cancer. Inflammation is implicated in the pathogenesis of myeloproliferative neoplasm (MPN). With a hypothesis that LD significantly contributes to MPN carcinogenesis by inducing abnormal inflammation, our objective was to elucidate the pathophysiological mechanisms of MPN arising from an LD background. METHODS: Genotyping of the LD background was performed in a cohort of MPN patients (n = 190) and healthy controls (n = 461). Logistic regression modeling, utilizing genotype data, was employed to estimate the correlation between LD and MPN. Whole transcriptome sequencing (WTS) (LD carriers = 8, non-carriers = 6) and single-cell RNA sequencing data (LD carriers = 2, non-carriers = 2, healthy controls = 2) were generated and analyzed. RESULTS: A higher variant frequency of LD was observed in MPN compared to healthy controls (healthy, 4.9%; MPN, 7.8%), with the highest frequency seen in polycythemia vera (PV) (odds ratio = 2.33, p = 0.03). WTS revealed that LD carriers exhibited upregulated inflammatory cytokine ligand-receptor genes, pathways, and network modules in MPNs compared to non-carriers. At the single-cell level, there was monocyte expansion and elevation of cytokine ligand-receptor interactions, inflammatory transcription factors, and network modules centered on monocytes. Notably, Oncostatin-M (OSM) consistently emerged as a candidate molecule involved in the pathogenesis of LD-related PV. CONCLUSIONS: In summary, an LD background is prevalent in MPN patients and leads to increased cytokine dysregulation and inflammation. OSM, as one of the potential molecules, plays a crucial role in PV pathogenesis by impairing lysosomal function.


Assuntos
Lisossomos , Transtornos Mieloproliferativos , Humanos , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Lisossomos/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Estudos de Casos e Controles , Idoso , Inflamação/genética , Citocinas/metabolismo , Citocinas/genética , Policitemia Vera/genética , Policitemia Vera/metabolismo , Policitemia Vera/patologia , Adulto , Perfilação da Expressão Gênica , Análise de Célula Única
14.
Cell Rep ; 43(9): 114674, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39299237

RESUMO

Innate immunity in bacteria, plants, and animals requires the specialized subset of Toll/interleukin-1/resistance gene (TIR) domain proteins that are nicotinamide adenine dinucleotide (NAD+) hydrolases. Aggregation of these TIR proteins engages their enzymatic activity, but it is unknown how this protein multimerization is regulated. Here, we discover that TIR oligomerization is controlled to prevent immune toxicity. We find that p38 propagates its own activation in a positive feedback loop, which promotes the aggregation of the lone enzymatic TIR protein in the nematode C. elegans (TIR-1, homologous to human sterile alpha and TIR motif-containing 1 [SARM1]). We perform a forward genetic screen to determine how the p38 positive feedback loop is regulated. We discover that the integrity of the specific lysosomal subcompartment that expresses TIR-1 is actively maintained to limit inappropriate TIR-1 aggregation on the membranes of these organelles, which restrains toxic propagation of p38 innate immunity. Thus, innate immunity in C. elegans intestinal epithelial cells is regulated by specific control of TIR-1 multimerization.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Imunidade Inata , Lisossomos , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/imunologia , Lisossomos/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Receptores de Superfície Celular/metabolismo , Agregados Proteicos , Multimerização Proteica , Receptores Acoplados a Proteínas G
15.
CNS Neurosci Ther ; 30(9): e70054, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39306799

RESUMO

OBJECTIVES: This study aims to elucidate the role of Fe2+ overload in kainic acid (KA)-induced excitotoxicity, investigate the involvement of ferritinophagy selective cargo receptor NCOA4 in the pathogenesis of excitotoxicity. METHODS: Western blotting was used to detect the expression of FTH1, NCOA4, Lamp2, TfR, FPN, and DMT1 after KA stereotaxic injection into the unilateral striatum of mice. Colocalization of Fe2+ with lysosomes in KA-treated primary cortical neurons was observed by using confocal microscopy. Desferrioxamine (DFO) was added to chelate free iron, a CCK8 kit was used to measure cell viability, and the Fe2+ levels were detected by FerroOrange. BODIPY C11 was used to determine intracellular lipid reactive oxygen species (ROS) levels, and the mRNA levels of PTGS2, a biomarker of ferroptosis, were measured by fluorescent quantitative PCR. 3-Methyladenine (3-MA) was employed to inhibit KA-induced activation of autophagy, and changes in ferritinophagy-related protein expression and the indicated biomarkers of ferroptosis were detected. Endogenous NCOA4 was knocked down by lentivirus transfection, and cell viability and intracellular Fe2+ levels were observed after KA treatment. RESULTS: Western blot results showed that the expression of NCOA4, DMT1, and Lamp2 was significantly upregulated, while FTH1 was downregulated, but there were no significant changes in TfR and FPN. The fluorescence results indicated that KA enhanced the colocalization of free Fe2+ with lysosomes in neurons. DFO intervention could effectively rescue cell damage, reduce intracellular lipid peroxidation, and decrease the increased transcript levels of PTGS2 caused by KA. Pretreatment with 3-MA effectively reversed KA-induced ferritinophagy and ferroptosis. Endogenous interference with NCOA4 significantly improved cell viability and reduced intracellular free Fe2+ levels in KA-treated cells. CONCLUSION: KA-induced excitotoxicity activates ferritinophagy, and targeting ferritinophagy effectively inhibits downstream ferroptosis. Interference with NCOA4 effectively attenuates KA-induced neuronal damage. This study provides a potential therapeutic target for excitotoxicity related disease conditions.


Assuntos
Ferritinas , Ferroptose , Neurônios , Coativadores de Receptor Nuclear , Animais , Ferroptose/efeitos dos fármacos , Ferroptose/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Camundongos , Ferritinas/metabolismo , Coativadores de Receptor Nuclear/metabolismo , Coativadores de Receptor Nuclear/genética , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Camundongos Endogâmicos C57BL , Masculino , Receptores da Transferrina/metabolismo , Receptores da Transferrina/genética , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Ferro/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Proteína 2 de Membrana Associada ao Lisossomo/genética , Sistema y+ de Transporte de Aminoácidos , Proteínas de Transporte de Cátions
16.
Front Cell Infect Microbiol ; 14: 1442995, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39310786

RESUMO

Chlamydia are Gram-negative, obligate intracellular bacterial pathogens that infect eukaryotic cells and reside within a host-derived vacuole known as the inclusion. To facilitate intracellular replication, these bacteria must engage in host-pathogen interactions to obtain nutrients and membranes required for the growth of the inclusion, thereby sustaining prolonged bacterial colonization. Autophagy is a highly conserved process that delivers cytoplasmic substrates to the lysosome for degradation. Pathogens have developed strategies to manipulate and/or exploit autophagy to promote their replication and persistence. This review delineates recent advances in elucidating the interplay between Chlamydia trachomatis infection and autophagy in recent years, emphasizing the intricate strategies employed by both the Chlamydia pathogens and host cells. Gaining a deeper understanding of these interactions could unveil novel strategies for the prevention and treatment of Chlamydia infection.


Assuntos
Autofagia , Infecções por Chlamydia , Chlamydia trachomatis , Interações Hospedeiro-Patógeno , Autofagia/fisiologia , Chlamydia trachomatis/patogenicidade , Chlamydia trachomatis/fisiologia , Humanos , Infecções por Chlamydia/microbiologia , Vacúolos/microbiologia , Animais , Lisossomos/microbiologia , Lisossomos/metabolismo
17.
Traffic ; 25(9): e12956, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39313937

RESUMO

Limited nutrient availability in the tumor microenvironment can cause the rewiring of signaling and metabolic networks to confer cancer cells with survival advantages. We show here that the limitation of glucose, glutamine and serum from the culture medium resulted in the survival of a population of cancer cells with high viability and capacity to form tumors in vivo. These cells also displayed a remarkable increase in the abundance and size of lysosomes. Moreover, lysosomes were located mainly in the perinuclear region in nutrient-limited cells; this translocation was mediated by a rapid post-transcriptional increase in the key endolysosomal trafficking protein Rab7a. The acidic lysosomes in nutrient-limited cells could trap weakly basic drugs such as doxorubicin, mediating resistance of the cells to the drug, which could be partially reversed with the lysosomal inhibitor bafilomycin A1. An in vivo chorioallantoic membrane (CAM) assay indicated a remarkable decrease in microtumor volume when nutrient-limited cells were treated with 5-Fluorouracil (5-FU) and bafilomycin A1 compared to cells treated with either agent alone. Overall, our data indicate the activation of complementary pathways with nutrient limitation that can enable cancer cells to survive, proliferate and acquire drug resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Lisossomos , Macrolídeos , Proteínas rab de Ligação ao GTP , proteínas de unión al GTP Rab7 , Lisossomos/metabolismo , Humanos , proteínas de unión al GTP Rab7/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , Macrolídeos/farmacologia , Nutrientes/metabolismo , Linhagem Celular Tumoral , Fluoruracila/farmacologia , Animais , Doxorrubicina/farmacologia , Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/patologia , Neoplasias/tratamento farmacológico
18.
Biochemistry (Mosc) ; 89(7): 1300-1312, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39218026

RESUMO

To date, the molecular mechanisms of the common neurodegenerative disorder Parkinson's disease (PD) are unknown and, as a result, there is no neuroprotective therapy that may stop or slow down the process of neuronal cell death. The aim of the current study was to evaluate the prospects of using the mTOR molecule as a potential target for PD therapy due to the dose-dependent effect of mTOR kinase activity inhibition on cellular parameters associated with, PD pathogenesis. The study used peripheral blood monocyte-derived macrophages and SH-SY5Y neuroblastoma cell line. As a result, we have for the first time showed that inhibition of mTOR by Torin1 only at a concentration of 100 nM affects the level of the lysosomal enzyme glucocerebrosidase (GCase), encoded by the GBA1 gene. Mutations in GBA1 are considered a high-risk factor for PD development. This concentration led a decrease in pathological phosphorylated alpha-synuclein (Ser129), an increase in its stable tetrameric form with no changes in the lysosomal enzyme activities and concentrations of lysosphingolipids. Our findings suggest that inhibition of the mTOR protein kinase could be a promising approach for developing therapies for PD, particularly for GBA1-associated PD.


Assuntos
Lisossomos , Macrófagos , Doença de Parkinson , Serina-Treonina Quinases TOR , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Lisossomos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Doença de Parkinson/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Linhagem Celular Tumoral , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Neuroblastoma/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Relação Dose-Resposta a Droga , Glucosilceramidase/metabolismo , Glucosilceramidase/antagonistas & inibidores , Naftiridinas
19.
Theranostics ; 14(13): 4983-5000, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39267779

RESUMO

Rationale: Neovascular ocular diseases (NODs) represent the leading cause of visual impairment globally. Despite significant advances in anti-angiogenic therapies targeting vascular endothelial growth factor (VEGF), persistent challenges remain prevalent. As a proof-of-concept study, we herein demonstrate the effectiveness of targeted degradation of VEGF with bispecific aptamer-based lysosome-targeting chimeras (referred to as VED-LYTACs). Methods: VED-LYTACs were constructed with three distinct modules: a mannose-6-phosphate receptor (M6PR)-binding motif containing an M6PR aptamer, a VEGF-binding module with an aptamer targeting VEGF, and a linker essential for bridging and stabilizing the two-aptamer structure. The degradation efficiency of VED-LYTACs via the autophagy-lysosome system was examined using an enzyme-linked immunosorbent assay (ELISA) and immunofluorescence staining. Subsequently, the anti-angiogenic effects of VED-LYTACs were evaluated using in vitro wound healing assay, tube formation assay, three-dimensional sprouting assay, and ex vivo aortic ring sprouting assay. Finally, the potential therapeutic effects of VED-LYTACs on pathological retinal neovascularization and vascular leakage were tested by employing mouse models of NODs. Results: The engineered VED-LYTACs promote the interaction between M6PR and VEGF, consequently facilitating the translocation and degradation of VEGF through the lysosome. Our data show that treatment with VED-LYTACs significantly suppresses VEGF-induced angiogenic activities both in vitro and ex vivo. In addition, intravitreal injection of VED-LYTACs remarkably ameliorates abnormal vascular proliferation and leakage in mouse models of NODs. Conclusion: Our findings present a novel strategy for targeting VEGF degradation with an aptamer-based LYTAC system, effectively ameliorating pathological retinal angiogenesis. These results suggest that VED-LYTACs have potential as therapeutic agents for managing NODs.


Assuntos
Aptâmeros de Nucleotídeos , Lisossomos , Neovascularização Retiniana , Fator A de Crescimento do Endotélio Vascular , Animais , Aptâmeros de Nucleotídeos/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Camundongos , Neovascularização Retiniana/tratamento farmacológico , Neovascularização Retiniana/metabolismo , Humanos , Lisossomos/metabolismo , Lisossomos/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Inibidores da Angiogênese/farmacologia , Angiogênese
20.
Nano Lett ; 24(37): 11573-11580, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39225423

RESUMO

Lysosome-targeting chimera (LYTAC) shows great promise for protein-based therapeutics by targeted degradation of disease-associated membrane or extracellular proteins, yet its efficiency is constrained by the limited binding affinity between LYTAC reagents and designated proteins. Here, we established a programmable and multivalent LYTAC system by tandem assembly of DNA into a high-affinity protein degrader, a heterodimer aptamer nanostructure targeting both pathogenic membrane protein and lysosome-targeting receptor (insulin-like growth factor 2 receptor, IGF2R) with adjustable spatial distribution or organization pattern. The DNA-based multivalent LYTACs showed enhanced efficacy in removing immune-checkpoint protein programmable death-ligand 1 (PD-L1) and vascular endothelial growth factor receptor 2 (VEGFR2) in tumor cell membrane that respectively motivated a significant increase in T cell activity and a potent effect on cancer cell growth inhibition. With high programmability and versatility, this multivalent LYTAC system holds considerable promise for realizing protein therapeutics with enhanced activity.


Assuntos
Aptâmeros de Nucleotídeos , Lisossomos , Humanos , Lisossomos/metabolismo , Aptâmeros de Nucleotídeos/química , Linhagem Celular Tumoral , Nanoestruturas/química , DNA/química , DNA/metabolismo , Antígeno B7-H1/metabolismo , Receptor IGF Tipo 2/metabolismo , Receptor IGF Tipo 2/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/química , Proteólise
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