Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
1.
Nutrients ; 15(7)2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37049564

RESUMEN

To explore the mechanism by which Akkermansia muciniphila cell-free supernatant improves glucose and lipid metabolisms in Caenorhabditis elegans, the present study used different dilution concentrations of Akkermansia muciniphila cell-free supernatant as an intervention for with Caenorhabditis elegans under a high-glucose diet. The changes in lifespan, exercise ability, level of free radicals, and characteristic indexes of glucose and lipid metabolisms were studied. Furthermore, the expression of key genes of glucose and lipid metabolisms was detected by qRT-PCR. The results showed that A. muciniphila cell-free supernatant significantly improved the movement ability, prolonged the lifespan, reduced the level of ROS, and alleviated oxidative damage in Caenorhabditis elegans. A. muciniphila cell-free supernatant supported resistance to increases in glucose and triglyceride induced by a high-glucose diet and downregulated the expression of key genes of glucose metabolism, such as gsy-1, pygl-1, pfk-1.1, and pyk-1, while upregulating the expression of key genes of lipid metabolism, such as acs-2, cpt-4, sbp-1, and tph-1, as well as down-regulating the expression of the fat-7 gene to inhibit fatty acid biosynthesis. These findings indicated that A. muciniphila cell-free supernatant, as a postbiotic, has the potential to prevent obesity and improve glucose metabolism disorders and other diseases.


Asunto(s)
Glucosa , Metabolismo de los Lípidos , Animales , Glucosa/metabolismo , Caenorhabditis elegans/metabolismo , Verrucomicrobia , Lípidos
2.
Sci Rep ; 12(1): 16399, 2022 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-36180511

RESUMEN

Malignant brain tumors consist of malignancies originated primarily within the brain and the metastatic lesions disseminated from other organs. In spite of intensive studies, malignant brain tumors remain to be a medical challenge. Patient-derived organoid (PDO) can recapitulate the biological features of the primary tumor it was derived from and has emerged as a promising drug-screening model for precision therapy. Here we show a proof-of-concept based on early clinical study entailing the organoids derived from the surgically resected tumors of 26 patients with advanced malignant brain tumors enrolled during December 2020 to October 2021. The tumors included nine glioma patients, one malignant meningioma, one primary lymphoma patient, and 15 brain metastases. The primary tumor sites of the metastases included five from the lungs, three from the breasts, two from the ovaries, two from the colon, one from the testis, one of melanoma origin, and one of chondrosarcoma. Out of the 26 tissues, 13 (50%) organoids were successfully generated with a culture time of about 2 weeks. Among these patients, three were further pursued to have the organoids derived from their tumor tissues tested for the sensitivity to different therapeutic drugs in parallel to their clinical care. Our results showed that the therapeutic effects observed by the organoid models were consistent to the responses of these patients to their treatments. Our study suggests that PDO can recapitulate patient responses in the clinic with high potential of implementation in personalized medicine of malignant brain tumors.


Asunto(s)
Neoplasias Encefálicas , Organoides , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Humanos , Masculino , Medicina de Precisión/métodos
3.
Front Oncol ; 12: 851795, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35992877

RESUMEN

The cGAS-STING axis is one of the key mechanisms guarding cells from pathogen invasion in the cytoplasmic compartment. Sensing of foreign DNA in the cytosol by the cGAS-STING axis triggers a stress cascade, culminating at stimulation of the protein kinase TBK1 and subsequently activation of inflammatory response. In cancer cells, aberrant metabolism of the genomic DNA induced by the hostile milieu of tumor microenvironment or stresses brought about by cancer therapeutics are the major causes of the presence of nuclear DNA in the cytosol, which subsequently triggers a stress response. However, how the advanced tumors perceive and tolerate the potentially detrimental effects of cytosolic DNA remains unclear. Here we show that growth limitation by serum starvation activated the cGAS-STING pathway in breast cancer cells, and inhibition of cGAS-STING resulted in cell death through an autophagy-dependent mechanism. These results suggest that, instead of being subject to growth inhibition, tumors exploit the cGAS-STING axis and turn it to a survival advantage in the stressful microenvironment, providing a new therapeutic opportunity against advanced cancer. Concomitant inhibition of the cGAS-STING axis and growth factor signaling mediated by the epidermal growth factor receptor (EGFR) synergistically suppressed the development of tumor organoids derived from primary tumor tissues of triple-negative breast cancer (TNBC). The current study unveils an unexpected function of the cGAS-STING axis in promoting cancer cell survival and the potential of developing the stress-responding pathway as a therapeutic target, meanwhile highlights the substantial concerns of enhancing the pathway's activity as a means of anti-cancer treatment.

4.
World J Surg Oncol ; 20(1): 273, 2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36045445

RESUMEN

BACKGROUND: Previous studies have found that lncRNA polymorphisms are associated with the prognosis of gastric cancer (GC), but the specific roles of many lncRNA polymorphism sites in gastric cancer are still unclear. Our study aims to deeply explore the relationship between genetic polymorphism of lncRNA and the prognosis of GC. METHODS: The genotypes of candidate SNP locus were detected by Sequenom Mass ARRAY SNP. We deeply analyzed the association of lncRNA polymorphisms with GC prognosis by univariate and multivariate Cox regression, stratified analysis, conjoint analysis, and log-rank test. RESULTS: We found that mutations at rs2579878 and rs10036719 loci reduced the risk of poor prognosis of GC. Stratified analysis showed that rs2795025, rs10036719, and rs12516079 polymorphisms were all associated with tumor prognosis. In addition, conjoint analyses showed that the interaction between these two polymorphic sites (rs2795025 and rs12516079) could increase the risk of poor prognosis. Multivariate analysis also found that the AG/AA genotype of rs10036719 and AG genotype of rs12516079 were independent prognostic factors. Moreover, the high expression of both CCDC26 and LINC02122 were shown to be associated with the poor survival status of GC patients. CONCLUSIONS: We find that the genetic polymorphism of lncRNA plays a role in the development of GC and is closely related to the survival time of patients. It could serve as a predictor of the prognosis of GC.


Asunto(s)
ARN Largo no Codificante , Neoplasias Gástricas , Predisposición Genética a la Enfermedad , Humanos , Polimorfismo de Nucleótido Simple , Pronóstico , ARN Largo no Codificante/genética , Neoplasias Gástricas/patología
5.
Int J Mol Sci ; 23(10)2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35628489

RESUMEN

Invasion is the most prominent lethal feature of malignant cancer. However, how cell proliferation, another important feature of tumor development, is integrated with tumor invasion and the subsequent cell dissemination from primary tumors is not well understood. Proliferating cell nuclear antigen (PCNA) is essential for DNA replication in cancer cells. Loss of phosphorylation at tyrosine 211 (Y211) in PCNA (pY211-PCNA) mitigates PCNA function in proliferation, triggers replication fork arrest/collapse, which in turn sets off an anti-tumor inflammatory response, and suppresses distant metastasis. Here, we show that pY211-PCNA is important in stromal activation in tumor tissues. Loss of the phosphorylation resulted in reduced expression of mesenchymal proteins as well as tumor progenitor markers, and of the ability of invasion. Spontaneous mammary tumors that developed in mice lacking Y211 phosphorylation contained fewer tumor-initiating cells compared to tumors in wild-type mice. Our study demonstrates a novel function of PCNA as an essential factor for maintaining cancer stemness through Y211 phosphorylation.


Asunto(s)
Invasividad Neoplásica , Neoplasias , Células Madre Neoplásicas , Antígeno Nuclear de Célula en Proliferación , Animales , Proliferación Celular , Replicación del ADN , Ratones , Fosforilación , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo
6.
Comput Struct Biotechnol J ; 20: 241-251, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35024096

RESUMEN

Programmed cell death protein 1 (PD-1)/ programmed cell death protein ligand 1 (PD-L1) is the key immune checkpoint governing evasion of advanced cancer from immune surveillance. Immuno-oncology (IO) therapy targeting PD-1/PD-L1 with traditional antibodies is a promising approach to multiple cancer types but to which the response rate remains moderate in breast cancer, calling for the need of exploring alternative IO targeting approaches. A miRNA-gene network was integrated by a bioinformatics approach and corroborated with The Cancer Genome Atlas (TCGA) to screen miRNAs regulating immune checkpoint genes and associated with patient survival. Here we show the identification of a novel microRNA miR-4759 which repressed RNA expression of the PD-L1 gene. miR-4759 targeted the PD-L1 gene through two binding motifs in the 3' untranslated region (3'-UTR) of PD-L1. Reconstitution of miR-4759 inhibited PD-L1 expression and sensitized breast cancer cells to killing by immune cells. Treatment with miR-4759 suppressed tumor growth of orthotopic xenografts and promoted tumor infiltration of CD8+ T lymphocytes in immunocompetent mice. In contrast, miR-4759 had no effect to tumor growth in immunodeficient mice. In patients with breast cancer, expression of miR-4759 was preferentially downregulated in tumors compared to normal tissues and was associated with poor overall survival. Together, our results demonstrated miR-4759 as a novel non-coding RNA which promotes anti-tumor immunity of breast cancer.

7.
Am J Cancer Res ; 11(9): 4455-4469, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34659898

RESUMEN

Anti-estrogens as hormone therapy are the mainstay treatment for estrogen receptor (ER)-positive breast cancer. ER inhibitors through modulating the transcriptional function of ER have been the frontline anti-estrogens to which refractory phenotype often developed in advanced cancer. The anti-estrogen fulvestrant is currently the only clinically approved pure anti-estrogen which causes ER degradation. However, resistance to fulvestrant still occurs and unfortunately it leaves few choices other than chemotherapy as the later-line treatments to fulvestrant-resistant tumors. Here we show that fulvestrant resistance was accompanied by increased expression of a number of innate immune response genes including the natural killer (NK) cell ligand B7-H6 on the cell surface. In an attempt to overcome the drug resistance phenotype, a NK-based molecular approach taking advantage of a chimeric antigen receptor (CAR) system targeting B7-H6 was established and tested in cells with acquired resistance to fulvestrant. The results demonstrate that the cell therapy approach as a single agent can effectively induce cell death of the resistant cancer cells which is enhanced by the increased expression of cell surface B7-H6. This approach departs from the traditional strategies of conquering anti-estrogen resistant breast cancer and offers a new avenue to eradicate hormone-refractory malignant solid tumors.

8.
Cancer Metab ; 9(1): 34, 2021 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-34565479

RESUMEN

BACKGROUND: Metabolite genome-wide association studies (mGWAS) are key for understanding the genetic regulation of metabolites in complex diseases including cancers. Although mGWAS has revealed hundreds of metabolomics quantitative trait loci (mQTLs) in the general population, data relating to gastric cancer (GC) are still incomplete. METHODS: We identified mQTLs associated with GC by analyzing genome-wide and metabolome-wide datasets generated from 233 GC patients and 233 healthy controls. RESULTS: Twenty-two metabolites were statistically different between GC cases and healthy controls, and all of them were associated with the risk of gastric cancer. mGWAS analyses further revealed that 9 single nucleotide polymorphisms (SNPs) were significantly associated with 3 metabolites. Of these 9 SNPs, 6 loci were never reported in the previous mGWAS studies. Surprisingly, 4 of 9 SNPs were significantly enriched in genes involved in the T cell receptor signaling pathway. CONCLUSIONS: Our study unveiled several novel GC metabolite and genetic biomarkers, which may be implicated in the prevention and diagnosis of gastric cancer.

9.
Ecotoxicol Environ Saf ; 225: 112725, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34492628

RESUMEN

Despite the wide application of cobalt nanoparticles (CoNPs), its neurotoxicity and the underlying mechanisms are not fully understood. In this study, CoNPs-induced toxic effect was examined in both C57BL/6J mice and microglial BV2 cells. CoNPs-induced brain weight loss and the reduction of Nissl bodies, assuring neural damage. Moreover, both total unphosphorylated Tau and phosphorylated Tau (pTau; T231 and S262) expressions in the hippocampus and cortex were upregulated, unveiling Tau phosphorylation. Besides, the increase in inflammation-related proteins NLRP3 and IL-1ß were found in mice brain. Corroborating that, microglial marker Iba-1 expression was also increased, suggesting microglia-involved inflammation. Among the NADPH oxidase (NOX) family proteins tested, only NOX2 was activated by CoNPs in hippocampus. Therefore, BV2 cells were employed to further investigate the role of NOX2. In BV2 cells, NOX2 expression was upregulated, corresponding to the production of ROS. Moreover, similar induction in Tau phosphorylation and inflammation-related protein expressions were observed in CoNPs-exposed BV2 cells. Treatment of apocynin, a NOX2 inhibitor, reduced ROS generation and reversed Tau phosphorylation and inflammation caused by CoNPs. Thus, CoNPs induced ROS production, Tau phosphorylation and inflammation specially via NOX2 activation.


Asunto(s)
Microglía , Nanopartículas , Animales , Cobalto , Ratones , Ratones Endogámicos C57BL , Fosforilación
10.
Cell Rep ; 36(8): 109537, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34433039

RESUMEN

Increased DNA replication and metastasis are hallmarks of cancer progression, while deregulated proliferation often triggers sustained replication stresses in cancer cells. How cancer cells overcome the growth stress and proceed to metastasis remains largely elusive. Proliferating cell nuclear antigen (PCNA) is an indispensable component of the DNA replication machinery. Here, we show that phosphorylation of PCNA on tyrosine 211 (pY211-PCNA) regulates DNA metabolism and tumor microenvironment. Abrogation of pY211-PCNA blocks fork processivity, resulting in biogenesis of single-stranded DNA (ssDNA) through a MRE11-dependent mechanism. The cytosolic ssDNA subsequently induces inflammatory cytokines through a cyclic GMP-AMP synthetase (cGAS)-dependent cascade, triggering an anti-tumor immunity by natural killer (NK) cells to suppress distant metastasis. Expression of pY211-PCNA is inversely correlated with cytosolic ssDNA and associated with poor survival in patients with cancer. Our results pave the way to biomarkers and therapies exploiting immune responsiveness to target metastatic cancer.


Asunto(s)
Neoplasias Experimentales/inmunología , Antígeno Nuclear de Célula en Proliferación/inmunología , Escape del Tumor , Microambiente Tumoral/inmunología , Animales , Femenino , Humanos , Células MCF-7 , Ratones , Ratones Transgénicos , Neoplasias Experimentales/genética , Neoplasias Experimentales/mortalidad , Fosforilación , Antígeno Nuclear de Célula en Proliferación/genética , Microambiente Tumoral/genética , Tirosina/genética , Tirosina/inmunología
11.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34203261

RESUMEN

A group of clinically approved cancer therapeutic tyrosine kinase inhibitors was screened to test their effects on the expression of angiotensin-converting enzyme 2 (ACE2), the cell surface receptor for SARS-CoV-2. Here, we show that the receptor tyrosine kinase inhibitor imatinib (also known as STI571, Gleevec) can inhibit the expression of the endogenous ACE2 gene at both the transcript and protein levels. Treatment with imatinib resulted in inhibition of cell entry of the viral pseudoparticles (Vpps) in cell culture. In FVB mice orally fed imatinib, tissue expression of ACE2 was reduced, specifically in the lungs and renal tubules, but not in the parenchyma of other organs such as the heart and intestine. Our finding suggests that receptor tyrosine kinases play a role in COVID-19 infection and can be therapeutic targets with combined treatments of the best conventional care of COVID-19.


Asunto(s)
Enzima Convertidora de Angiotensina 2/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Mesilato de Imatinib/farmacología , SARS-CoV-2/fisiología , Internalización del Virus/efectos de los fármacos , Enzima Convertidora de Angiotensina 2/química , Enzima Convertidora de Angiotensina 2/genética , Animales , COVID-19/patología , COVID-19/virología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Femenino , Genes Reporteros , Humanos , Ratones , Regiones Promotoras Genéticas , SARS-CoV-2/aislamiento & purificación
12.
J Hazard Mater ; 419: 126378, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34175703

RESUMEN

Cobalt is a hazardous material that has harmful effects on neurotoxicity. Excessive exposure to cobalt or inactivation of the unique proline isomerase Pin1 contributes to age-dependent neurodegeneration. However, nothing is known about the role of Pin1 in cobalt-induced neurodegeneration. Here we find that out of several hazardous materials, only cobalt dose-dependently decreased Pin1 expression and alterations in its substrates, including cis and trans phosphorylated Tau in human neuronal cells, concomitant with neurotoxicity. Cobalt-induced neurotoxicity was aggravated by Pin1 genetic or chemical inhibition, but rescued by Pin1 upregulation. Furthermore, less than 4 µg/l of blood cobalt induced dose- and age-dependent Pin1 downregulation in murine brains, ensuing neurodegenerative changes. These defects were corroborated by changes in Pin1 substrates, including cis and trans phosphorylated Tau, amyloid precursor protein, ß amyloid and GSK3ß. Moreover, blood Pin1 was downregulated in human hip replacement patients with median blood cobalt level of 2.514 µg/l, which is significantly less than the safety threshold of 10 µg/l, suggesting an early role Pin1 played in neurodegenerative damages. Thus, Pin1 inactivation by cobalt contributes to age-dependent neurodegeneration, revealing that cobalt is a hazardous material triggering AD-like neurodegenerative damages.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Cobalto/toxicidad , Humanos , Ratones , Peptidilprolil Isomerasa de Interacción con NIMA/genética , Fosforilación
13.
Nat Commun ; 12(1): 2788, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33986289

RESUMEN

Human ribonuclease 1 (hRNase 1) is critical to extracellular RNA clearance and innate immunity to achieve homeostasis and host defense; however, whether it plays a role in cancer remains elusive. Here, we demonstrate that hRNase 1, independently of its ribonucleolytic activity, enriches the stem-like cell population and enhances the tumor-initiating ability of breast cancer cells. Specifically, secretory hRNase 1 binds to and activates the tyrosine kinase receptor ephrin A4 (EphA4) signaling to promote breast tumor initiation in an autocrine/paracrine manner, which is distinct from the classical EphA4-ephrin juxtacrine signaling through contact-dependent cell-cell communication. In addition, analysis of human breast tumor tissue microarrays reveals a positive correlation between hRNase 1, EphA4 activation, and stem cell marker CD133. Notably, high hRNase 1 level in plasma samples is positively associated with EphA4 activation in tumor tissues from breast cancer patients, highlighting the pathological relevance of the hRNase 1-EphA4 axis in breast cancer. The discovery of hRNase 1 as a secretory ligand of EphA4 that enhances breast cancer stemness suggests a potential treatment strategy by inactivating the hRNase 1-EphA4 axis.


Asunto(s)
Neoplasias de la Mama/patología , Carcinogénesis/patología , Efrina-A4/metabolismo , Células Madre Neoplásicas/patología , Ribonucleasa Pancreática/metabolismo , Antígeno AC133/metabolismo , Animales , Neoplasias de la Mama/genética , Carcinogénesis/genética , Línea Celular , Femenino , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Unión Proteica/genética , Ribonucleasa Pancreática/sangre , Ribonucleasa Pancreática/genética , Resultado del Tratamiento
14.
Am J Cancer Res ; 11(3): 945-954, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33791165

RESUMEN

Long non-coding RNAs (lncRNAs) are increasingly recognized as promising targets in cancer treatment. However, compared to targeting the ordinary protein-coding genes, suppressing non-coding RNAs expressed in cancer cells has been a more challenging task. The major hurdles lay on the requirement of a tumor-specific delivery system for the designated inhibitor to suppress the target transcripts within the cellular compartment. EGFR is a cancer driver gene which is frequently associated with the triple-negative phenotype of breast cancer. Prior studies have shown that expression of the tumor-promoting lncRNA HOTAIR (HOX antisense intergenic RNA) is positively regulated by the epithelial growth factor receptor (EGFR) in triple-negative breast cancer (TNBC), and consistently the expression of both genes is closely correlated in breast cancer. Here we show that a chimeric aptamer recognizing the epithelial growth factor receptor (EGFR) coupled with a siRNA against HOTAIR (EGFR aptamer-coupled siHOTAIR) preferentially and effectively down-regulated HOTAIR in EGFR-expressing cancer cells. Functionally, the EGFR aptamer-coupled siHOTAIR more potently inhibited the growth, migration, and invasion of EGFR-expressing TNBC cells as well as cells with reconstituted EGFR compared to cancer cells with low EGFR expression. Our results demonstrate a novel strategy of targeting cancer progression by aptamer-directed delivery of anti-lncRNA RNA interference that can be applicable to other cellular contexts and cancer types.

15.
Ecotoxicol Environ Saf ; 209: 111832, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33383341

RESUMEN

Cobalt has been known for its neurotoxicity in numerous studies. However, the molecular mechanism underlying cobalt-induced neurotoxicity remains largely unknown. In this study, two neuroblastoma (SHSY5Y and N2a) cell lines and a phaeochromocytoma (PC12) line were used as in vitro models. Cells were treated for 24 h with 50, 100, 200, 300, 400 µM cobalt chloride (CoCl2) or cultured with 300 µM CoCl2 for 4, 8, 12 and 24 h to investigate the effects of histone acetylation on CoCl2-induced neurodegenerative damages. Our findings demonstrate that CoCl2 suppresses the acetylation of histone H3 and H4 in a time-dependent and dosage-dependent manner. Furthermore, CoCl2 selectively decreases the expression and activity of histone acetyltransferase (HAT) but has no effects on histone deacetylase (HDAC) in SHSY5Y cells. More importantly, we show that 100 ng/mL HDAC inhibitor trichostatin (TSA) pre-treatment partly attenuates 300 µM CoCl2-induced neurodegenerative damages in SHSY5Y cells. Mechanistic analyses show that CoCl2-induced neurodegenerative damages are associated with the dysfunction of APP, BACE1, PSEN1, NEP and HIF-1α genes, whose expression are partly mediated by histone modification. In summary, we demonstrate that histone acetylation is involved in CoCl2-induced neurodegenerative damages. Our study indicates an important connection between histone modification and the pathological process of neurodegenerative damages and provides a mechanism for cobalt-mediated epigenetic regulation.


Asunto(s)
Cobalto/toxicidad , Histonas/fisiología , Sistema Nervioso/efectos de los fármacos , Acetilación/efectos de los fármacos , Secretasas de la Proteína Precursora del Amiloide/genética , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/genética , Ácido Aspártico Endopeptidasas/metabolismo , Línea Celular Tumoral , Cobalto/metabolismo , Epigénesis Genética/efectos de los fármacos , Inhibidores de Histona Desacetilasas/metabolismo , Histonas/metabolismo , Humanos , Ácidos Hidroxámicos , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patología , Pruebas de Toxicidad
16.
J Cell Physiol ; 236(5): 3660-3674, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33034385

RESUMEN

The underlying mechanisms of complement activation in Stargardt disease type 1 (STGD1) and age-related macular degeneration (AMD) are not fully understood. Overaccumulation of all-trans-retinal (atRAL) has been proposed as the pathogenic factor in both diseases. By incubating retinal pigment epithelium (RPE) cells with atRAL, we showed that C5b-9 membrane attack complexes (MACs) were generated mainly through complement alternative pathway. An increase in complement factor B (CFB) expression as well as downregulation of complement regulatory proteins CD46, CD55, CD59, and CFH were observed in RPE cells after atRAL treatment. Furthermore, interleukin-1ß production was provoked in both atRAL-treated RPE cells and microglia/macrophages. Coincubation of RPE cells with interleukin-1 receptor antagonist (IL1Ra) and atRAL ameliorated complement activation and downregulated CFB expression by attenuating both p38 and c-Jun N-terminal kinase (JNK) signaling pathways. Our findings demonstrate that atRAL induces an autocrine/paracrine IL-1/IL-1R signaling to promote complement alternative pathway activation in RPE cells and provide a novel perspective on the pathomechanism of macular degeneration.


Asunto(s)
Activación de Complemento/efectos de los fármacos , Vía Alternativa del Complemento/efectos de los fármacos , Interleucina-1/metabolismo , Receptores de Interleucina-1/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Retinaldehído/farmacología , Transducción de Señal , Acetilcisteína/farmacología , Animales , Células Cultivadas , Factor B del Complemento/metabolismo , Regulación hacia Abajo , Humanos , Interleucina-1/genética , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Microglía/efectos de los fármacos , Microglía/metabolismo , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Modelos Biológicos , Epitelio Pigmentado de la Retina/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Porcinos , Transcripción Genética/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
17.
Nanotoxicology ; 15(10): 1358-1379, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-35077651

RESUMEN

Broad applications of cobalt nanoparticles (CoNPs) have raised increased concerns regarding their potential toxicity. However, the underlining mechanisms of their toxicity have yet to be characterized. Here, we demonstrated that CoNPs reduced cell viability and induced membrane leakage. CoNPs induced oxidative stress, as indicated by the generation of reactive oxygen species (ROS) secondary to the increased expression of hypoxia-induced factor 1 alpha. Moreover, CoNPs led to mitochondrial damage, including generation of mitochondrial ROS, reduction in ATP content, morphological damage and autophagy. Interestingly, exogenous mitochondria were observed between neurons and astrocytes upon CoNPs exposure. Concomitantly, tunneling nanotubes (TNTs)-like structures were observed between neurons and astrocytes upon CoNPs exposure. These structures were further verified to be TNTs as they were found to be F-actin rich and lacking tubulin. We then demonstrated that TNTs were utilized for mitochondrial transfer between neurons and astrocytes, suggesting a novel crosstalk phenomenon between these cells. Moreover, we found that the inhibition of TNTs (using actin-depolymerizing drug latrunculin B) intensified apoptosis triggered by CoNPs. Therefore, we demonstrate, for the first time, that the inhibition of intercellular mitochondrial transfer via TNTs aggravates CoNPs-induced cellular and mitochondrial toxicity in neuronal cells, implying a novel intercellular protection mechanism in response to nanoparticle exposure.


Asunto(s)
Nanopartículas , Nanotubos , Estructuras de la Membrana Celular , Cobalto/toxicidad , Mitocondrias , Nanopartículas/toxicidad , Nanotubos/toxicidad
18.
Ecotoxicol Environ Saf ; 208: 111424, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33120262

RESUMEN

Emerging evidences having suggested that particular lncRNAs have a potential effect on PD progression through provoking damage and inflammatory responses of microglia/ dopaminergic cells. In addition, paraquat can be accumulated in human body through various approaches and have an increased risk for Parkinson's disease. However, the specific role and mechanism of lncRNA related to neurotoxic in the progression of PD is unclear. In our study, a mouse PD model was established induced by the intraperitoneal injection of paraquat (5 mg/kg and 10 mg/kg) every three days (10 times). We determined differential expression of lncRNA AK039862 and its potential targeted genes Pafah1b1/Foxa1 in PD mouse model, then we used fluorescence in situ hybridization (FISH) to visualize the cellular distribution of AK039862. Short interfering RNAs (siRNAs) and overexpression plasmids were designed for knockdown or overexpression of AK039862. To simulate the coexisting dopaminergic cells and microglia cells in vitro, we applied several non-contact co-culture models, including conditioned medium and Transwell co-culture systems. Cytotoxicity of PQ was evaluated using bv2 cells with the concentrations: 30, 60 µM, and mn9d cells with the concentrations: 50, 100 µM. As a result, we depicted multiple interesting individual and interactive features of inflammatory lncRNA AK039862 involved in PQ-induced cellular functional effects. First, we detected that AK039862 contributed to the neuronal injury process in PQ-treated mice and co-localization of AK039862 with dopaminergic cells in vivo. And interestingly, we demonstrated that PQ significantly inhibited microglia and dopaminergic cells proliferation and microglia migration in vitro. Further research indicated that the PQ-induced low expression of AK039862 rescued microglia proliferation and migration inhibition via the AK039862/Pafah1b1/Foxa1 pathway. Meanwhile, AK039862 also participated in the interaction between microglia and dopaminergic cells with PQ treatment in non-contact co-culture models. In summary, we found that PQ inhibited the proliferation and migration of microglial cells, and elucidated AK039862 played a key role in PQ-induced neuroinflammatory damage through Pafah1b1/Foxa1. Finally, inflammatory AK039862 is involved in the complex communication between microglia and dopaminergic cells in the environment of PQ damage.


Asunto(s)
Herbicidas/toxicidad , Paraquat/toxicidad , ARN Largo no Codificante/metabolismo , 1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , 1-Alquil-2-acetilglicerofosfocolina Esterasa/farmacología , Animales , Proliferación Celular , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/metabolismo , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Factor Nuclear 3-alfa del Hepatocito/farmacología , Hibridación Fluorescente in Situ , Masculino , Ratones , Microglía/efectos de los fármacos , Proteínas Asociadas a Microtúbulos/metabolismo , Síndromes de Neurotoxicidad/metabolismo
19.
Front Public Health ; 8: 390, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32923419

RESUMEN

Background: It is generally accepted that learning engagement is predictive of better learning outcomes. Yet, there might be some underlying motives for students to engage in or disengage from learning. Aims: Grounded in self-determination theory, this study aimed to examine whether satisfaction of international students' innate needs for autonomy, competence, and relatedness correlated positively with their engagement in learning and improvement of health literacy in China. Sample: Forty-three international undergraduates from a medical university in China participated in the study. Methods: Both qualitative and quantitative methods were used to deal with data collected from surveys on health literacy, perceived need satisfaction and the need satisfaction intervention, and from observation log recording dynamic changes in the students' performance while implementing a need-satisfying scheme in Hygiene education. In addition, final examination scores of with/without-intervention parts were compared to unveil the effect of the intervention. Results: Perceived autonomy support motivated the participants to engage actively in learning; close relation to peers and teachers encouraged them to take on challenges; satisfying their need for competence enabled them to have better performance and academic achievements as well as an improvement on health literacy. Conclusions: The present study suggested that fulfillment of the students' basic needs contributes to their engagement in learning and improvement of health literacy.


Asunto(s)
Alfabetización en Salud , China , Humanos , Motivación , Autonomía Personal , Estudiantes
20.
Environ Pollut ; 266(Pt 2): 115326, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32827984

RESUMEN

Excessive exposure to cobalt (Co) is known to make adverse impact on the nervous system, but its detailed mechanisms of neurotoxicity have yet to be determined. In this study, C57BL/6 mice (0, 4, 8, 16 mg/kg CoCl2, 30 days) and human neuroblastoma H4 cells (0, 100, 400, 600 µM CoCl2) were used as in vivo and in vitro models. Our results revealed that CoCl2 intraperitoneal injection caused significant impairments in learning and memory, as well as pathological damage in the nervous system. We further certificated the alteration of m6A methylation induced by CoCl2 exposure. Our findings demonstrate for the first time, significant differences in the degree of m6A modification, the biological function of m6A-modified transcripts between cortex and H4 cell samples. Specifically, MeRIP-seq and RNA-seq elucidate that CoCl2 exposure results in differentially m6A-modified and expressed genes, which were enriched in pathways involving synaptic transmission, and central nervous system (CNS) development. Mechanistic analyses revealed that CoCl2 remarkably changed m6A modification level by affecting the expression of m6A methyltransferase and demethylase, and decreasing the activity of demethylase. We observed variation of m6A modification in neurodegenerative disease-associated genes upon CoCl2 exposure and identified regulatory strategy between m6A and potential targets mRNA. Our novel findings provide novel insight into the functional roles of m6A modification in neurodegenerative damage caused by environmental neurotoxicants and identify Co-mediated specific RNA regulatory strategy for broadening the epigenetic regulatory mechanism of RNA induced by heavy metals.


Asunto(s)
Cobalto , Neuroblastoma , Enfermedades Neurodegenerativas , ARN , Adenosina/análogos & derivados , Animales , Cobalto/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Aprendizaje , Memoria , Ratones , Ratones Endogámicos C57BL , ARN/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA