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1.
Adv Mater ; : e2406682, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837816

RESUMEN

The utilization of rare earth elements to regulate the interaction between catalysts and oxygen-containing species holds promising prospects in the field of oxygen electrocatalysis. Through structural engineering and adsorption regulation, it is possible to achieve high-performance catalytic sites with a broken activity-stability tradeoff. Herein, this work fabricates a hierarchical CeO2/NiCo hydroxide for electrocatalytic oxygen evolution reaction (OER). This material exhibits superior overpotentials and enhanced stability. Multiple potential-dependent experiments reveal that CeO2 promotes oxygen-species exchange, especially OH- ions, between catalyst and environment, thereby optimizing the redox transformation of hydroxide and the adsorption of oxygen-containing intermediates during OER. This is attributed to the reduction in the adsorption energy barrier of Ni to *OH facilitated by CeO2, particularly the near-interfacial Ni sites. The less-damaging adsorbate evolution mechanism and the CeO2 hierarchical shell significantly enhance the structural robustness, leading to exceptional stability. Additionally, the observed "self-healing" phenomenon provides further substantiation for the accelerated oxygen exchange. This work provides a neat strategy for the synthesis of ceria-based complex hollow electrocatalysts, as well as an in-depth insight into the co-catalytic role of CeO2 in terms of oxygen transfer.

2.
Cell Death Discov ; 10(1): 132, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38472215

RESUMEN

Small bowel vascular malformation disease (SBVM) commonly causes obscure gastrointestinal bleeding (OGIB). However, the pathogenetic mechanism and the role of lncRNAs in SBVM remain largely unknown. Here, we found that hypoxia and low-glucose environments co-augment angiogenesis and existed in SBVM. Mechanistically, hypoxia and low-glucose environments supported angiogenesis via activation of hypoxia and glucose deprivation-induced lncRNA (HGDILnc1) transcription by increasing binding of the NeuroD1 transcription factor to the HGDILnc1 promoter. Raised HGDILnc1 acted as a suppressor of α-Enolase 1 (ENO1) small ubiquitin-like modifier modification (SUMOylation)-triggered ubiquitination, and an activator of transcription of Aldolase C (ALDOC) via upregulation of Histone H2B lysine 16 acetylation (H2BK16ac) level in the promoter of ALDOC, and consequently promoting glycolysis and angiogenesis. Moreover, HGDILnc1 was clinically positively correlated with Neurogenic differentiation 1 (NeuroD1), ENO1, and ALDOC in SBVM tissues, and could function as a biomarker for SBVM diagnosis and therapy. These findings suggest that hypoxia and low-glucose environments were present in SBVM tissues, and co-augmented angiogenesis. Hypoxia and low-glucose environments co-induced HGDILnc1, which is higher expressed in SBVM tissue compared with normal tissue, could promoted glycolysis and angiogenesis.

3.
J Am Chem Soc ; 146(8): 5324-5332, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38355103

RESUMEN

The low coverage rate of anode OH adsorption under high current density conditions has become an important factor restricting the development of an industrial alkaline water electrolyzer (AWE). Here, we present our rare earth modification promotion strategy on using the rare earth oxygen-friendly interface to increase the OH coverage of the NiS2 surface for efficient AWE anode catalysis. Density functional theory calculations predict that rare earths can enhance the coverage of surface OH, and the synthesis reaction mechanism is discussed in the synthesis process spectrum. Experimentally, by preparing a series of rare-earth-modified NiS2, the relationship between OH coverage, active site density, and catalytic activity was established by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, time-resolved absorption spectra, and so on. The unique oxygenophilic properties of rare earths enhance OH coverage, thereby increasing the density of active sites for efficient catalysis. Furthermore, Eu2O3/NiS2 was assembled into the AWE equipment and operated stably for over 240 h at a current density of 300 mA cm-2 under industrial conditions of 80 °C and 30% KOH. Rare-earth-modified NiS2 exhibits better catalytic activity than traditional non-noble metal anode catalysts Ni(OH)2 and NiS2, providing a new approach for rare earth promotion to solve the problem of low OH coverage in the AWE anode.

4.
Small ; 19(40): e2303099, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37269214

RESUMEN

Copper-based electrocatalysts effectively produce multicarbon (C2+ ) compounds during the electrochemical CO2 reduction (CO2 RR). However, big challenges still remain because of the chemically unstable active sites. Here, cerium is used as a self-sacrificing agent to stabilize the Cu+ of CuS, due to the facile Ce3+ /Ce4+ redox. CeO2 -modified CuS nanoplates achieve high ethanol selectivity, with FE up to 54% and FEC2+ ≈ 75% in a flow cell. Moreover, in situ Raman spectroscopy and in situ Fourier-transform infrared spectroscopy indicate that the stable Cu+ species promote CC coupling step under CO2 RR. Density functional theory calculations further reveal that the stronger * CO adsorption and lower CC coupling energy, which is conducive to the selective generation of ethanol products. This work provides a facile strategy to convert CO2 into ethanol by retaining Cu+ species.

5.
Nat Commun ; 14(1): 1949, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37029185

RESUMEN

Dynamic reconstruction of metal sulphides during electrocatalytic oxygen evolution reaction (OER) has hampered the acquisition of legible evidence for comprehensively understanding the phase-transition mechanism and electrocatalytic activity origin. Herein, modelling on a series of cobalt-nickel bimetallic sulphides, we for the first time establish an explicit and comprehensive picture of their dynamic phase evaluation pathway at the pre-catalytic stage before OER process. By utilizing the in-situ electrochemical transmission electron microscopy and electron energy loss spectroscopy, the lattice sulphur atoms of (NiCo)S1.33 particles are revealed to be partially substituted by oxygen from electrolyte to form a lattice oxygen-sulphur coexisting shell surface before the generation of reconstituted active species. Such S-O exchange process is benefitted from the subtle modulation of metal-sulphur coordination form caused by the specific Ni and Co occupation. This unique oxygen-substitution behaviour produces an (NiCo)OxS1.33-x surface to reduce the energy barrier of surface reconstruction for converting sulphides into active oxy/hydroxide derivative, therefore significantly increasing the proportion of lattice oxygen-mediated mechanism compared to the pure sulphide surface. We anticipate this direct observation can provide an explicit picture of catalysts' structural and compositional evolution during the electrocatalytic process.

6.
Int J Mol Sci ; 24(6)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36982619

RESUMEN

Short-chain fatty acids (SCFAs) are important metabolites of the intestinal flora that are closely related to the development of non-alcoholic fatty liver disease (NAFLD). Moreover, studies have shown that macrophages have an important role in the progression of NAFLD and that a dose effect of sodium acetate (NaA) on the regulation of macrophage activity alleviates NAFLD; however, the exact mechanism of action remains unclear. This study aimed to assess the effect and mechanism of NaA on regulating the activity of macrophages. RAW264.7 and Kupffer cells cell lines were treated with LPS and different concentrations of NaA (0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, and 5 mM). Low doses of NaA (0.1 mM, NaA-L) significantly increased the expression of inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin 1 beta (IL-1ß); it also increased the phosphorylation of inflammatory proteins nuclear factor-κB p65 (NF-κB p65) and c-Jun (p < 0.05), and the M1 polarization ratio of RAW264.7 or Kupffer cells. Contrary, a high concentration of NaA (2 mM, NaA-H) reduced the inflammatory responses of macrophages. Mechanistically, high doses of NaA increased intracellular acetate concentration in macrophages, while a low dose had the opposite effect, consisting of the trend of changes in regulated macrophage activity. Besides, GPR43 and/or HDACs were not involved in the regulation of macrophage activity by NaA. NaA significantly increased total intracellular cholesterol (TC), triglycerides (TG), and lipid synthesis gene expression levels in macrophages and hepatocytes at either high or low concentrations. Furthermore, NaA regulated the intracellular AMP/ATP ratio and AMPK activity, achieving a bidirectional regulation of macrophage activity, in which the PPARγ/UCP2/AMPK/iNOS/IκBα/NF-κB signaling pathway has an important role. In addition, NaA can regulate lipid accumulation in hepatocytes by NaA-driven macrophage factors through the above-mentioned mechanism. The results revealed that the mode of NaA bi-directionally regulating the macrophages further affects hepatocyte lipid accumulation.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Acetato de Sodio/farmacología , FN-kappa B/metabolismo , Metabolismo de los Lípidos , Proteínas Quinasas Activadas por AMP/metabolismo , Macrófagos/metabolismo , Hepatocitos/metabolismo , Lípidos/farmacología , Lipopolisacáridos/farmacología
7.
Nanoscale ; 15(9): 4477-4487, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36752707

RESUMEN

Electrocatalytic reduction of CO2 to formate is considered as a promising method to achieve carbon neutrality, and the introduction of heteroatoms is an effective strategy to improve the catalytic activity and selectivity of catalysts. However, the structural reconstruction behavior of catalysts driven by voltage is usually ignored. Therefore, we used Cu/Bi2S3 as a model to reveal the dynamic reduction process in different atmospheric environments. The catalyst showed an outstanding faradaic efficiency of 94% for formate and a long-term stability of 100 h, and exhibited a high current density of 280 mA cm-2 in a flow cell. The experimental results and theoretical calculations show that the introduction of copper enhances the adsorption of CO2, accelerates the charge transfer and reduces the formation barrier of *OCHO, thus promoting the formation of formate. This work draws attention to the effects of saturated gases in the electrolyte during structural evolution and provides a possibility for designing catalysts with high catalytic activity.

8.
EMBO Rep ; 24(4): e56325, 2023 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-36794620

RESUMEN

The frequency of p53 mutations in colorectal cancer (CRC) is approximately 40-50%. A variety of therapies are being developed to target tumors expressing mutant p53. However, potential therapeutic targets for CRC expressing wild-type p53 are rare. In this study, we show that METTL14 is transcriptionally activated by wild-type p53 and suppresses tumor growth only in p53-wild-type (p53-WT) CRC cells. METTL14 deletion promotes both AOM/DSS and AOM-induced CRC growth in mouse models with the intestinal epithelial cell-specific knockout of METTL14. Additionally, METTL14 restrains aerobic glycolysis in p53-WT CRC, by repressing SLC2A3 and PGAM1 expression via selectively promoting m6 A-YTHDF2-dependent pri-miR-6769b/pri-miR-499a processing. Biosynthetic mature miR-6769b-3p and miR-499a-3p decrease SLC2A3 and PGAM1 levels, respectively, and suppress malignant phenotypes. Clinically, METTL14 only acts as a beneficial prognosis factor for the overall survival of p53-WT CRC patients. These results uncover a new mechanism for METTL14 inactivation in tumors and, most importantly, reveal that the activation of METTL14 is a critical mechanism for p53-dependent cancer growth inhibition, which could be targeted for therapy in p53-WT CRC.


Asunto(s)
Neoplasias Colorrectales , MicroARNs , Animales , Ratones , Carcinogénesis/genética , Línea Celular Tumoral , Proliferación Celular/genética , Transformación Celular Neoplásica/genética , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , Glucólisis/genética , MicroARNs/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
9.
Commun Biol ; 5(1): 1248, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36376440

RESUMEN

To explore highly selective targeting molecules of colorectal cancer (CRC) is a challenge. We previously identified a twelve-amino acid peptide (LPKTVSSDMSLN, namely P-LPK) by phage display technique which may specifically binds to CRC cells. Here we show that P-LPK selectively bind to a panel of human CRC cell lines and CRC tissues. In vivo, Gallium-68 (68Ga) labeled P-LPK exhibits selective accumulation at tumor sites. Then, we designed a peptide-conjugated drug comprising P-LPK and camptothecin (CPT) (namely P-LPK-CPT), and found P-LPK-CPT significantly inhibits tumor growth with fewer side effects in vitro and in vivo. Furthermore, through co-immunoprecipitation and molecular docking experiment, the glutamine transporter solute carrier 1 family member 5 (SLC1A5) was identified as the possible target of P-LPK. The binding ability of P-LPK and SLC1A5 is verified by surface plasmon resonance and immunofluorescence. Taken together, P-LPK-CPT is highly effective for CRC and deserves further development as a promising anti-tumor therapeutic for CRC, especially SLC1A5-high expression type.


Asunto(s)
Camptotecina , Neoplasias Colorrectales , Humanos , Camptotecina/farmacología , Camptotecina/química , Simulación del Acoplamiento Molecular , Péptidos/metabolismo , Glutamina/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Antígenos de Histocompatibilidad Menor/metabolismo , Sistema de Transporte de Aminoácidos ASC/metabolismo
10.
Anal Methods ; 13(43): 5144-5156, 2021 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-34727151

RESUMEN

Symbiotic gut microbiota in early life plays a vital role in human health, and changes in its communication and function are associated with various complex disorders. In this study, we analyzed the gut flora communication of 6 infants at 4 months of age and determined the disturbances related to antibiotic treatment. By the culturomics and Single Molecule Real-time sequencing methods, a total of 6234 strains were divided into 16 genera and 45 species. The alpha diversity of culturable microorganisms in amoxicillin-treated infants was significantly less than that in healthy infants (p <0.05), as indicated by Chao 1, observed species and Faith's PD index. According to metagenomics, the dominant genus and species were Bifidobacterium and B. longum in the healthy group. After treatment with amoxicillin, the dominant genus and species shifted to Enterococcus and E. faecium. Based on the functional annotation of metagenomics, amoxicillin affected the metabolic function of the gut microbiome by activating carbohydrate and lipid metabolism and inhibiting amino acid metabolism. Besides, the intake of antibiotics in early life increased the risk of neurodegenerative disease, virus infectious disease and antimicrobial resistance. The Antibiotic Resistance Genes Database annotation result indicated that the abundance of drug-resistance genes in the antibiotic group was higher than that in the healthy group. These genes were associated with resistance to bacitracin, most of which were associated with K. pneumonia. These findings can provide guidance in the clinic on the proper usage of antibiotics.


Asunto(s)
Microbioma Gastrointestinal , Enfermedades Neurodegenerativas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Microbioma Gastrointestinal/genética , Humanos , Lactante , Metagenómica/métodos , Análisis de Secuencia de ADN
11.
Cell Death Differ ; 28(11): 3105-3124, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34021267

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human cancers. It thrives in a malnourished environment; however, little is known about the mechanisms by which PDAC cells actively promote aerobic glycolysis to maintain their metabolic needs. Gene Expression Omnibus (GEO) was used to identify differentially expressed miRNAs. The expression pattern of miR-30d in normal and PDAC tissues was studied by in situ hybridization. The role of miR-30d/RUNX1 in vitro and in vivo was evaluated by CCK8 assay and clonogenic formation as well as transwell experiment, subcutaneous xenograft model and liver metastasis model, respectively. Glucose uptake, ATP and lactate production were tested to study the regulatory effect of miR-30d/RUNX1 on aerobic glycolysis in PDAC cells. Quantitative real-time PCR, western blot, Chip assay, promoter luciferase activity, RIP, MeRIP, and RNA stability assay were used to explore the molecular mechanism of YTHDC1/miR-30d/RUNX1 in PDAC. Here, we discover that miR-30d expression was remarkably decreased in PDAC tissues and associated with good prognosis, contributed to the suppression of tumor growth and metastasis, and attenuation of Warburg effect. Mechanistically, the m6A reader YTHDC1 facilitated the biogenesis of mature miR-30d via m6A-mediated regulation of mRNA stability. Then, miR-30d inhibited aerobic glycolysis through regulating SLC2A1 and HK1 expression by directly targeting the transcription factor RUNX1, which bound to the promoters of the SLC2A1 and HK1 genes. Moreover, miR-30d was clinically inversely correlated with RUNX1, SLC2A1 and HK1, which function as adverse prognosis factors for overall survival in PDAC tissues. Overall, we demonstrated that miR-30d is a functional and clinical tumor-suppressive gene in PDAC. Our findings further uncover that miR-30d is a novel target for YTHDC1 through m6A modification, and miR-30d represses pancreatic tumorigenesis via suppressing aerobic glycolysis.


Asunto(s)
Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , MicroARNs/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Factores de Empalme de ARN/metabolismo , Adenocarcinoma/patología , Animales , Carcinogénesis , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Desnudos , Pronóstico , Efecto Warburg en Oncología
12.
Exp Gerontol ; 150: 111376, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-33905875

RESUMEN

Gut microbial metabolites, SCFAs, were related with the occurrence and development of Parkinson's disease (PD). But the effects of different short-chain fatty acids (SCFAs) on PD and involving mechanisms are still undefined. In this study we evaluate the effects of three dominant SCFAs (acetate, propionate and butyrate) on motor damage, dopaminergic neuronal degeneration and underlying neuroinflammation related mechanisms in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced PD mice. High (2.0 g/kg) or low doses (0.2 g/kg) of sodium acetate (NaA), sodium propionate (NaP) or sodium butyrate (NaB) were gavaged into PD mice for 6 weeks. High doses of NaA reduced the turning time of PD mice. NaB significantly reduced the turning and total time in pole test, and increased the average velocity in open field test when compared with PD mice, indicating the most effective alleviation of PD-induced motor disorder. Low and high doses of NaB significantly increased the content of tyrosine hydroxylase (TH) by 12.3% and 20.2%, while reduced α-synuclein activation by 159.4% and 132.7% in the substantia nigra pars compacta (SNpc), compared with PD groups. Butyrate reached into the midbrain SNpc and suppressed microglia over-activation. It inhibited the levels of pro-inflammatory factors (IL-6, IL-1ß and TNF-α) (P < 0.01) and iNOS. Besides, butyrate inhibited the activation of NF-κB and MAPK signaling pathways in the SNpc region. Consequently, sodium butyrate could inhibit neuroinflammation and alleviate neurological damage of PD.


Asunto(s)
Intoxicación por MPTP , Fármacos Neuroprotectores , Enfermedad de Parkinson , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Animales , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas , Ácidos Grasos Volátiles , Ratones , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , Enfermedad de Parkinson/tratamiento farmacológico
13.
Oncogenesis ; 10(1): 4, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33419984

RESUMEN

Exploring novel anticancer drugs to optimize the efficacy may provide a benefit for the treatment of colorectal cancer (CRC). Disulfiram (DSF), as an antialcoholism drug, is metabolized into diethyldithiocarbamate-copper complex (CuET) in vivo, which has been reported to exert the anticancer effects on various tumors in preclinical studies. However, little is known about whether CuET plays an anti-cancer role in CRC. In this study, we found that CuET had a marked effect on suppressing CRC progression both in vitro and in vivo by reducing glucose metabolism. Mechanistically, using RNA-seq analysis, we identified ALDH1A3 as a target gene of CuET, which promoted cell viability and the capacity of clonal formation and inhibited apoptosis in CRC cells. MicroRNA (miR)-16-5p and 15b-5p were shown to synergistically regulate ALDH1A3, which was negatively correlated with both of them and inversely correlated with the survival of CRC patients. Notably, using co-immunoprecipitation followed with mass spectrometry assays, we identified PKM2 as a direct downstream effector of ALDH1A3 that stabilized PKM2 by reducing ubiquitination. Taken together, we disclose that CuET treatment plays an active role in inhibiting CRC progression via miR-16-5p and 15b-5p/ALDH1A3/PKM2 axis-mediated aerobic glycolysis pathway.

15.
Neoplasia ; 22(11): 590-603, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32992138

RESUMEN

Most colorectal cancer (CRC) are characterized by allele loss of the genes located on the short arm of chromosome 17 (17p13.1), including the tumor suppressor p53 gene. Although important, p53 is not the only driver of chromosome 17p loss. In this study, we explored the biological and prognostic significance of genes around p53 on 17p13.1 in CRC. The Cancer Genome Atlas (TCGA) were used to identify differentially expressed genes located between 1000 kb upstream and downstream of p53 gene. The function of CLDN7 was evaluated by both in vitro and in vivo experiments. Quantitative real-time PCR, western blot, and promoter luciferase activity, immunohistochemistry were used to explore the molecular drivers responsible for the development and progression of CRC. The results showed that CLDN7, located between 1000 kb upstream and downstream of p53 gene, were remarkably differentially expressed in tumor and normal tissues. CLDN7 expression also positively associated with p53 level in different stages of the adenoma-carcinoma sequence. Both in vitro and in vivo assays showed that CLDN7 inhibited cell proliferation in p53 wild type CRC cells, but had no effects on p53 mutant CRC cells. Mechanistically, p53 could bind to CLDN7 promoter region and regulate its expression. Clinically, high CLDN7 expression was negatively correlated with tumor size, invasion depth, lymphatic metastasis and AJCC III/IV stage, but was positively associated with favorable prognosis of CRC patients. Collectively, our work uncovers the tumor suppressive function for CLDN7 in a p53-dependent manner, which may mediate colorectal tumorigenesis induced by p53 deletion or mutation.


Asunto(s)
Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Claudinas/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteína p53 Supresora de Tumor/metabolismo , Animales , Línea Celular Tumoral , Cromosomas Humanos Par 17 , Claudinas/metabolismo , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Biología Computacional/métodos , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Ontología de Genes , Humanos , Estimación de Kaplan-Meier , Masculino , Ratones , Mutación , Pronóstico , Proteína p53 Supresora de Tumor/genética , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Food Funct ; 11(7): 5799-5814, 2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32568317

RESUMEN

Lipopolysaccharides (LPS), a main component of the Gram-negative bacterial cell wall, can damage the epithelial wall barrier and induce chronic intestinal inflammation. The purpose of this study is to evaluate whether the novel L. rhamnosus could alleviate intestinal inflammation and damage induced by LPS and explore the possible underlying molecular mechanism. L. rhamnosus JL-1 was selected from five L. rhamnosus strains due to its strong adherence capacity to Caco-2 cells (92.89%) and it could survive in simulated gastrointestinal juices. Whole genome sequencing analysis showed that there were no translocation and inversion regions in the genome of L. rhamnosus JL-1 compared with L. rhamnosus GG. Comparative genomic analysis showed that there were encoding genes related to adhesion, acid resistance and bile salt resistance in the genome of L. rhamnosus JL-1. Both in vitro and in vivo experiments indicated that LPS challenge inhibited the mRNA and protein expression of pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6). However, the mRNA and protein expressions of pro-inflammatory cytokines were inhibited by pre-treatment with L. rhamnosus JL-1 in a dose-dependent manner. The result of histopathology analysis of ileum showed that oral administration of L. rhamnosus JL-1 reduced pathological damage induced by LPS. Furthermore, it was revealed that L. rhamnosus JL-1 could inhibit the mRNA and protein expressions of TLR4 and NF-κB. These results strongly suggested that L. rhamnosus JL-1 relieved LPS-induced intestinal inflammation by inhibiting the TLR4/NF-κB signaling pathway. To sum up, L. rhamnosus JL-1 has a potential probiotic function and plays an important role in preventing LPS-induced intestinal inflammation and damage.


Asunto(s)
Inflamación/terapia , Intestinos/microbiología , Lacticaseibacillus rhamnosus/metabolismo , Lipopolisacáridos/toxicidad , Probióticos , Animales , Adhesión Bacteriana , Células CACO-2 , Citocinas/metabolismo , Microbioma Gastrointestinal , Regulación Bacteriana de la Expresión Génica , Genómica , Humanos , Inflamación/etiología , Lacticaseibacillus rhamnosus/genética , Masculino , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Probióticos/administración & dosificación , ARN Bacteriano/genética , ARN Bacteriano/aislamiento & purificación , Transducción de Señal , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
17.
Oncogene ; 39(2): 469-485, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31597953

RESUMEN

The development of chemoresistance remains a major challenge that accounts for colorectal cancer (CRC) lethality. Dichloroacetate (DCA) was originally used as a metabolic regulator in the treatment of metabolic diseases; here, DCA was assayed to identify the mechanisms underlying the chemoresistance of CRC. We found that DCA markedly enhanced chemosensitivity of CRC cells to fluorouracil (5-FU), and reduced the colony formation due to high levels of apoptosis. Using the microarray assay, we noted that miR-149-3p was involved in the chemoresistance of CRC, which was modulated by wild-type p53 after DCA treatment. In addition, PDK2 was identified as a direct target of miR-149-3p. Mechanistic analyses showed that overexpression of miR-149-3p enhanced 5-FU-induced apoptosis and reduced glucose metabolism, similar to the effects of PDK2 knockdown. In addition, overexpression of PDK2 partially reversed the inhibitory effect of miR-149-3p on glucose metabolism. Finally, both DCA treatment and miR-149-3p overexpression in 5-FU-resistant CRC cells were found to markedly sensitize the chemotherapeutic effect of 5-FU in vivo, and this effect was also validated in a small retrospective cohort of CRC patients. Taken together, we determined that the p53/miR-149-3p/PDK2 signaling pathway can potentially be targeted with DCA treatment to overcome chemoresistant CRC.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Ácido Dicloroacético/farmacología , Glucosa/metabolismo , MicroARNs/genética , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis/efectos de los fármacos , Secuencia de Bases , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Ácido Dicloroacético/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Fluorouracilo/farmacología , Células HCT116 , Humanos , Masculino , Ratones
18.
J Cancer ; 10(24): 6037-6047, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31762813

RESUMEN

Chemoresistance is responsible for most colorectal cancer (CRC) related deaths. In this study, we found that dichloroacetate (DCA), a pyruvate dehydrogenase kinase (PDK) inhibitor, can be used as a sensitizer for oxaliplatin (L-OHP) chemoresistant CRC cells. The aim of this study was to explore the ability of DCA to overcome L-OHP resistance in CRC cells and to identify the underlying molecular mechanisms. We found that DCA sensitizes chemoresistant CRC cells to L-OHP-induced cytotoxic effects by inhibiting clone formation capacity and promoting cell apoptosis. A microRNA (miRNA) array was used for screen, and miR-543 was identified and shown to be downregulated after DCA treatment. The expression of miR-543 was higher in chemoresistant CRC cells than in chemosensitive CRC cells. Overexpression of miR-543 increased chemoresistance in CRC cells. The validated target gene, PTEN, was negatively regulated by miR-543 both in vitro and in vivo, and PTEN was upregulated by DCA through miR-543. In addition, overexpression of miR-543 reversed the inhibition of colony formation after DCA treatment. Furthermore, the Akt/mTOR pathway is activated by miR-543 and is involved in the miR-543 induced chemoresistance. There was a significant inverse relationship between miR-543 expression and PTEN level in CRC patients, and high miR-543 expression was associated with worse prognosis. In conclusion, DCA restored chemosensitivity through miR-543/PTEN/Akt/mTOR pathway, and miR-543 may be a potential marker or therapeutic target for chemoresistance in CRC.

19.
J Dairy Sci ; 102(9): 7684-7696, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31255276

RESUMEN

Oxidative stress is the basic reason for aging and age-related diseases. In this study, we investigated the protective effect of 2 strains of lactic acid bacteria (LAB), Lactobacillus rhamnosus GG and L. plantarum J26, against oxidative stress in Caco-2 cells, and gave an overview of the mechanisms of lactic acid bacteria antioxidant activity using digital gene expression profiling. The 2 LAB strains provided significant protection against hydrogen peroxide (H2O2)-induced reduction in superoxide dismutase activity and increase in glutathione peroxidase activity in Caco-2 cells. However, inactive bacteria had little effect on alleviating oxidation stress in Caco-2 cells. Eight genes related to oxidative stress-FOSB, TNF, PPP1R15A, NUAK2, ATF3, TNFAIP3, EGR2, and FBN2-were significantly upregulated in H2O2-induced Caco-2 cells compared with untreated Caco-2 cells. After incubation of the H2O2-induced Caco-2 cells with L. rhamnosus GG and L. plantarum J26, 5 genes (TNF, EGR2, NUAK2, FBN2, and TNFAIP3) and 2 genes (NUAK2 and FBN2) were downregulated, respectively. In addition, the Kyoto Encyclopedia of Genes and Genomes indicated that some signaling pathways associated with inflammation, immune response, and apoptosis, such as Janus kinase/signal transducers and activators of transcription (Jak-STAT), mitogen-activated protein kinase (MAPK), nuclear factor-κB, and tumor necrosis factor, were all negatively modulated by the 2 strains, especially L. rhamnosus GG. In this paper, we reveal the mechanism of LAB in relieving oxidative stress and provide a theoretical basis for the rapid screening and evaluation of new LAB resources.


Asunto(s)
Enterocitos/metabolismo , Lacticaseibacillus rhamnosus/fisiología , Lactobacillus plantarum/fisiología , Estrés Oxidativo/genética , Transcriptoma/genética , Animales , Apoptosis/genética , Células CACO-2 , Enterocitos/efectos de los fármacos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/fisiología , Humanos , Peróxido de Hidrógeno/farmacología , Inmunidad/genética , Inflamación/genética , Probióticos/farmacología
20.
J Cancer ; 8(8): 1498-1506, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28638466

RESUMEN

Background: Colon Cancer-Associated Transcript 2 (CCAT2) has been demonstrated associated with clinical outcomes in various tumors. However, the results from each study were unfortunately insufficient and not completely consistent. Therefore, we conduct a systematic meta-analysis to evaluate the value for a feasible biomarker for metastasis and prognosis. Methods: A meta-analysis was performed using data obtained through a systematic search of PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, Wanfang database and VIP database. The pooled odds ratio (OR) and hazard ratio (HR) with 95% Confidence interval (CI ) using random-effect were used to identify the relationship of CCAT2 with clinical outcome of cancer patients. Subgroup analysis and sensitivity analysis were performed. Results: A total of 867 patients from eight studies were finally included. Patients with high CCAT2 expression underwent an increased risk of lymph node metastasis (LNM) (OR=3.09, 95% CI: 1.53-6.26) and distant metastasis (DM) (OR=7.70, 95% CI: 3.26-18.17). CCAT2 was also significantly correlated with overall survival (OS) (HR=2.19, 95%CI: 1.70-2.82) and progression-free survival (PFS) (HR=2.59, 95% CI: 1.78-3.76). Moderate heterogeneity was observed in meta-analysis for LNM. However, the results remained robust in multiple sensitivity analyses. Conclusions: High expression of CCAT2 was linked with poor clinical outcome. CCAT2 can serve as a potential molecular marker for prognosis in different types of cancers.

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