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1.
Mol Cell ; 72(4): 753-765.e6, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30392931

RESUMEN

DNA methylation patterns regulate gene expression programs and are maintained through a highly coordinated process orchestrated by the RING E3 ubiquitin ligase UHRF1. UHRF1 controls DNA methylation inheritance by reading epigenetic modifications to histones and DNA to activate histone H3 ubiquitylation. Here, we find that all five domains of UHRF1, including the previously uncharacterized ubiquitin-like domain (UBL), cooperate for hemi-methylated DNA-dependent H3 ubiquitin ligation. Our structural and biochemical studies, including mutations found in cancer genomes, reveal a bifunctional requirement for the UBL in histone modification: (1) the UBL makes an essential interaction with the backside of the E2 and (2) the UBL coordinates with other UHRF1 domains that recognize epigenetic marks on DNA and histone H3 to direct ubiquitin to H3. Finally, we show UBLs from other E3s also have a conserved interaction with the E2, Ube2D, highlighting a potential prevalence of interactions between UBLs and E2s.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Metilación de ADN , Histonas/metabolismo , Secuencia de Aminoácidos , Proteínas Potenciadoras de Unión a CCAAT/genética , ADN/genética , ADN/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Epigénesis Genética , Histonas/genética , Humanos , Unión Proteica , Dominios Proteicos , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
2.
Eur J Immunol ; : e2350655, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973083

RESUMEN

Sepsis arises from an uncontrolled inflammatory response triggered by infection or stress, accompanied by alteration in cellular energy metabolism, and a strong correlation exists between these factors. Alpha-ketoglutarate (α-KG), an intermediate product of the TCA cycle, has the potential to modulate the inflammatory response and is considered a crucial link between energy metabolism and inflammation. The scavenger receptor (SR-A5), a significant pattern recognition receptor, assumes a vital function in anti-inflammatory reactions. In the current investigation, we have successfully illustrated the ability of α-KG to mitigate inflammatory factors in the serum of septic mice and ameliorate tissue damage. Additionally, α-KG has been shown to modulate metabolic reprogramming and macrophage polarization. Moreover, our findings indicate that the regulatory influence of α-KG on sepsis is mediated through SR-A5. We also elucidated the mechanism by which α-KG regulates SR-A5 expression and found that α-KG reduced the N6-methyladenosine level of macrophages by up-regulating the m6A demethylase ALKBH5. α-KG plays a crucial role in inhibiting inflammation by regulating SR-A5 expression through m6A demethylation during sepsis. The outcomes of this research provide valuable insights into the relationship between energy metabolism and inflammation regulation, as well as the underlying molecular regulatory mechanism.

3.
Rev Cardiovasc Med ; 25(5): 178, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-39076490

RESUMEN

Background: The pathogenesis and development of chronic heart failure (CHF) may involve long non-coding ribonucleic acid (lncRNA) steroid receptor RNA activator 1 (SRA1), a known cardiomyopathy risk factor and regulator of cardiac myofibroblast activation. This study aimed to investigate the application of SRA1 in the early detection and prediction of CHF. Methods: SRA1 plasma expression was determined in CHF patients and healthy individuals/using real time-quantitative polymerase chain reaction (RT-qPCR). The diagnostic and prognostic value of SRA1 was assessed using receiver operating curve (ROC) and Cox regression analyses. Results: Compared with the healthy controls, the patients with CHF had increased brain natriuretic peptide (BNP) levels, left atrial end-systolic diameter (LAD), left ventricular end-diastolic diameter (LVDd), and decreased left ventricular ejection fraction (LVEF). SRA1 was significantly upregulated in CHF patients as well as positively correlated with BNP level, LAD, and LVDd, and negatively correlated with LVEF. SRA1 could sensitively discriminate CHF patients from healthy individuals and was an independent predictor of adverse event-free survival in CHF patients. Conclusions: Upregulated plasma SRA1 can discriminate patients with CHF from healthy individuals and predict adverse outcomes in CHF patients. Thus, SRA1 is a potential molecular indicator for monitoring chronic heart failure development.

4.
Biochem Genet ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38530576

RESUMEN

Age-related cataract (ARC) is the prevalent cause of useful vision loss. Circular RNAs are related to ARC pathogenesis partly through their competing endogenous RNA (ceRNA) activity. Herein, we defined the action of hsa_circ_0105558 in hydrogen peroxide (H2O2)-driven apoptosis and oxidative damage in human lens epithelial SRA01/04 cells. Hsa_circ_0105558, microRNA (miR)-182-5p and activating transcription factor 6 (ATF6) were evaluated by a qRT-PCR or immunoblotting method. The hsa_circ_0105558/miR-182-5p and miR-182-5p/ATF6 relationships were predicted by bioinformatics analysis and confirmed by dual-luciferase reporter assay. Reactive oxygen species level, glutathione peroxidase level, superoxide dismutase activity, and malondialdehyde level were measured using the matched assay kits. Hsa_circ_0105558 was upregulated in human ARC lens and H2O2-exposed SRA01/04 cells. Suppression of hsa_circ_0105558 attenuated H2O2-driven SRA01/04 cell apoptosis and oxidative damage. Hsa_circ_0105558 targeted miR-182-5p, and reduced miR-182-5p expression reversed the influence of hsa_circ_0105558 depletion on H2O2-driven oxidative damage and apoptosis. ATF6 was a target of miR-182-5p, and miR-182-5p-driven downregulation of ATF6 regulated cell oxidative damage and apoptosis under H2O2 insult. Moreover, hsa_circ_0105558 functioned as a ceRNA to post-transcriptionally control ATF6 expression through miR-182-5p competition. Our study demonstrates that hsa_circ_0105558 modulates SRA01/04 cell oxidative damage and apoptosis under H2O2 insult through the miR-182-5p/ATF6 cascade.

5.
Risk Anal ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39074844

RESUMEN

Risk science is the most updated and justified knowledge-in the form of concepts, principles, approaches, methods, and models-for understanding, assessing, characterizing, communicating, and handling risk, with applications. It is also about the practice that gives us this knowledge. It is commonly stated that risk science is politically neutral. This perspective article discusses this assertion by scrutinizing the relationship between risk science and politics. In particular, it looks into the position of The Society for Risk Analysis (SRA) on this matter. Using some current risk problems as illustrating examples, including COVID-19 and climate change risk, the article argues that defending the political neutrality aim is paramount, especially with today's increasingly divisive political landscape.

6.
Int Ophthalmol ; 44(1): 316, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38969958

RESUMEN

BACKGROUND: Diabetic cataract (DC) is a common complication of diabetes and its etiology and progression are multi-factorial. In this study, the roles of specific protein 1 (SP1) and fibroblast growth factor 7 (FGF7) in DC development were explored. METHODS: DC cell model was established by treating SRA01/04 cells with high glucose (HG). MTT assay was conducted to evaluate cell viability. Transwell assay and wound-healing assay were performed to assess cell migration and invasion. Western blot assay and qRT-PCR assay were conducted to measure the expression of N-cadherin, E-cadherin, Collagen I, Fibronectin, SP1 and FGF7 expression. CHIP assay and dual-luciferase reporter assay were conducted to analyze the combination between FGF7 and SP1. RESULTS: FGF7 was upregulated in DC patients and HG-induced SRA01/04 cells. HG treatment promoted SRA01/04 cell viability, migration, invasion and epithelial-mesenchymal transition (EMT), while FGF7 knockdown abated the effects. Transcription factor SP1 activated the transcription level of FGF7 and SP1 overexpression aggravated HG-induced SRA01/04 cell injury. SP1 silencing repressed HG-induced SRA01/04 cell viability, migration, invasion and EMT, but these effects were ameliorated by upregulating FGF7. Additionally, SP1 knockdown inhibited the PI3K/AKT pathway by regulating the transcription level of FGF7. CONCLUSION: Transcription factor SP1 activated the transcription level of FGF7 and the PI3K/AKT pathway to regulate HG-induced SRA01/04 cell viability, migration, invasion and EMT.


Asunto(s)
Movimiento Celular , Supervivencia Celular , Células Epiteliales , Transición Epitelial-Mesenquimal , Factor 7 de Crecimiento de Fibroblastos , Glucosa , Cristalino , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Factor de Transcripción Sp1 , Transición Epitelial-Mesenquimal/efectos de los fármacos , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp1/genética , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Glucosa/farmacología , Células Epiteliales/metabolismo , Factor 7 de Crecimiento de Fibroblastos/metabolismo , Factor 7 de Crecimiento de Fibroblastos/genética , Factor 7 de Crecimiento de Fibroblastos/farmacología , Cristalino/metabolismo , Cristalino/citología , Catarata/metabolismo , Células Cultivadas , Regulación de la Expresión Génica
7.
Cell Commun Signal ; 21(1): 99, 2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-37143083

RESUMEN

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a serious side effect of chemotherapy with poorly understood mechanisms and few treatments. High-mobility group box 1 (HMGB1)-induced neuroinflammation is the main cause of CIPN. Here, we aimed to illustrate the role of the macrophage scavenger receptor A1 (SR-A1) in HMGB1 clearance and CIPN resolution. METHODS: Oxaliplatin (L-OHP) was used to establish a CIPN model. Recombinant HMGB1 (rHMGB1) (his tag) was used to evaluate the phagocytosis of HMGB1 by macrophages. RESULTS: In the clinic, HMGB1 expression and MMP-9 activity were increased in the plasma of patients with CIPN. Plasma HMGB1 expression was positively correlated with the cumulative dose of L-OHP and the visual analog scale. In vitro, engulfment and degradation of rHMGB1 increased and inflammatory factor expression decreased after AMP-activated protein kinase (AMPK) activation. Neutralizing antibodies, inhibitors, or knockout of SR-A1 abolished the effects of AMPK activation on rHMGB1 engulfment. In vivo, AMPK activation increased SR-A1 expression in the dorsal root ganglion, decreased plasma HMGB1 expression and MMP-9 activity, and attenuated CIPN, which was abolished by AMPK inhibition or SR-A1 knockout in the CIPN mice model. CONCLUSION: Activation of the AMPK/SR-A1 axis alleviated CIPN by increasing macrophage-mediated HMGB1 engulfment and degradation. Therefore, promoting HMGB1 clearance may be a potential treatment strategy for CIPN. Video abstract.


Asunto(s)
Antineoplásicos , Proteína HMGB1 , Enfermedades del Sistema Nervioso Periférico , Ratones , Animales , Proteínas Quinasas Activadas por AMP , Proteína HMGB1/metabolismo , Metaloproteinasa 9 de la Matriz , Oxaliplatino/efectos adversos , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Receptores Depuradores/uso terapéutico
8.
Mol Pharm ; 20(11): 5345-5358, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37870420

RESUMEN

An endogenous transporter protein called albumin interacts with the Fc receptor to provide it with multiple substrate-binding domains, cell membrane receptor activation, and an extended circulating half-life. Albumin has the remarkable ability to bind with receptors viz. secreted protein acidic and rich in cysteine (SPARC) and scavenger protein-A (SR-A) that are overexpressed during rheumatoid arthritis (RA), enabling active targeting of the disease site instead of requiring specialized substrates to be added to the nanocarrier. RA, a chronic autoimmune illness, is characterized by the presence of a severe inflammatory response. RA patients have low serum albumin concentration, which signifies the high uptake of albumin at the inflammatory sites, giving a rationale to use albumin as a drug carrier for RA therapy. Albumin has the capacity for both passive and active targeting. It is an abundantly available protein in the bloodstream showing excellent cellular compatibility, degradability in biological tissues, nonantigenicity, and safety. There are three strategies of albumin mediated drug delivery as encapsulating therapeutics in albumin nanoparticles, chemically conjugating drugs with functional proteins, and albumin itself which is used as a targeting ligand to deliver drugs specifically to cells or tissues that express albumin-binding receptors. In the current review, an attempt has been made to highlight the significant evidence of albumin as a drug delivery carrier for the safe and effective management of RA. Evidence has been provided in the form of recent research advances, clinical trials, and patents. Additionally, this review will outline the prospective for the potential utilization of albumin as a drug vehicle for RA and suggest possible future avenues to provide the perspective for subsequent studies.


Asunto(s)
Artritis Reumatoide , Portadores de Fármacos , Humanos , Portadores de Fármacos/química , Osteonectina/metabolismo , Estudios Prospectivos , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Albúminas/metabolismo
9.
Nitric Oxide ; 134-135: 61-71, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37059259

RESUMEN

Production of nitric oxide (NO) by LPS-activated macrophages is due to a complex cellular signaling initiated by TLR4 that leads to the transcription of IFN-ß, which activates IRF-1 and STAT-1, as well as to the activation of NF-κB, required for iNOS transcription. High concentrations of LPS can also be uptaken by scavenger receptors (SRs), which, in concert with TLR4, leads to inflammatory responses. The mechanisms by which TLR4 and SRs interact, and the pathways activated by this interaction in macrophages are not elucidated. Therefore, our main goal was to evaluate the role of SRs, particularly SR-A, in LPS-stimulated macrophages for NO production. We first showed that, surprisingly, LPS can induce the expression of iNOS and the production of NO in TLR4-/- mice, provided exogenous IFN-ß is supplied. These results indicate that LPS stimulate receptors other than TLR4. The inhibition of SR-A using DSS or neutralizing antibody to SR-AI showed that SR-A is essential for the expression of iNOS and NO production in stimulation of TLR4 by LPS. The restoration of the ability to express iNOS and produce NO by addition of rIFN-ß to inhibited SR-A cells indicated that the role of SR-AI in LPS-induced NO production is to provide IFN-ß, probably by mediating the internalization of LPS/TLR4, and the differential inhibition by DSS and neutralizing antibody to SR-AI suggested that other SRs are also involved. Our results reinforce that TLR4 and SR-A act in concert in LPS activation and demonstrated that, for the production of NO, it does mainly by synthesizing IRF-3 and also by activating the TRIF/IRF-3 pathway for IFN-ß production, essential for LPS-mediated transcription of iNOS. Consequently STAT-1 is activated, and IRF-1 is expressed, which together with NF-κB from TLR4/MyD88/TIRAP, induce iNOS synthesis and NO production. SUMMARY SENTENCE: TLR4 and SRs act in concert activating IRF-3 to transcribe IFN-ß and activate STAT-1 to produce NO by LPS-activated macrophages.


Asunto(s)
FN-kappa B , Óxido Nítrico , Ratones , Animales , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Receptor Toll-Like 4/metabolismo , Lipopolisacáridos , Macrófagos/metabolismo , Receptores Depuradores/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo
10.
BMC Bioinformatics ; 23(1): 77, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35193506

RESUMEN

BACKGROUND: Genome-wide protein-DNA binding is popularly assessed using specific antibody pulldown in Chromatin Immunoprecipitation Sequencing (ChIP-Seq) or Cleavage Under Targets and Release Using Nuclease (CUT&RUN) sequencing experiments. These technologies generate high-throughput sequencing data that necessitate the use of multiple sophisticated, computationally intensive genomic tools to make discoveries, but these genomic tools often have a high barrier to use because of computational resource constraints. RESULTS: We present a comprehensive, infrastructure-independent, computational pipeline called SEAseq, which leverages field-standard, open-source tools for processing and analyzing ChIP-Seq/CUT&RUN data. SEAseq performs extensive analyses from the raw output of the experiment, including alignment, peak calling, motif analysis, promoters and metagene coverage profiling, peak annotation distribution, clustered/stitched peaks (e.g. super-enhancer) identification, and multiple relevant quality assessment metrics, as well as automatic interfacing with data in GEO/SRA. SEAseq enables rapid and cost-effective resource for analysis of both new and publicly available datasets as demonstrated in our comparative case studies. CONCLUSIONS: The easy-to-use and versatile design of SEAseq makes it a reliable and efficient resource for ensuring high quality analysis. Its cloud implementation enables a broad suite of analyses in environments with constrained computational resources. SEAseq is platform-independent and is aimed to be usable by everyone with or without programming skills. It is available on the cloud at https://platform.stjude.cloud/workflows/seaseq and can be locally installed from the repository at https://github.com/stjude/seaseq .


Asunto(s)
Cromatina , Programas Informáticos , Inmunoprecipitación de Cromatina , Secuenciación de Inmunoprecipitación de Cromatina , Nube Computacional , Secuenciación de Nucleótidos de Alto Rendimiento
11.
Med Mycol ; 60(4)2022 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-35244718

RESUMEN

Scedosporium species are emerging opportunistic fungal pathogens causing various infections mainly in immunocompromised patients, but also in immunocompetent individuals, following traumatic injuries. Clinical manifestations range from local infections, such as subcutaneous mycetoma or bone and joint infections, to pulmonary colonization and severe disseminated diseases. They are commonly found in soil and other environmental sources. To date S. aurantiacum has been reported only from a handful of countries. To identify the worldwide distribution of this species we screened publicly available sequencing data from fungal metabarcoding studies in the Sequence Read Archive (SRA) of The National Centre for Biotechnology Information (NCBI) by multiple BLAST searches. S. aurantiacum was found in 26 countries and two islands, throughout every climatic region. This distribution is like that of other Scedosporium species. Several new environmental sources of S. aurantiacum including human and bovine milk, chicken and canine gut, freshwater, and feces of the giant white-tailed rat (Uromys caudimaculatus) were identified. This study demonstrated that raw sequence data stored in the SRA database can be repurposed using a big data analysis approach to answer biological questions of interest. LAY SUMMARY: To understand the distribution and natural habitat of S. aurantiacum, species-specific DNA sequences were searched in the SRA database. Our large-scale data analysis illustrates that S. aurantiacum is more widely distributed than previously thought and new environmental sources were identified.


Asunto(s)
Enfermedades de los Perros , Micetoma , Scedosporium , Animales , Perros , Huésped Inmunocomprometido , Micetoma/microbiología , Micetoma/veterinaria , Scedosporium/genética , Especificidad de la Especie
12.
Int J Mol Sci ; 23(14)2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35887326

RESUMEN

Due to its noninvasive nature, site-confined irradiation, and high tissue penetrating capabilities, ultrasound (US)-driven sonodynamic treatment (SDT) has been proven to have broad application possibilities in neoplastic and non-neoplastic diseases. However, the inefficient buildup of sonosensitizers in the tumor site remarkably impairs SDT efficiency. The present work proposes a deep-penetrating sonochemistry nanoplatform (Pp18-lipos@SRA737&DOX, PSDL) comprising Pp18 liposomes (Pp18-lipos, Plipo), SRA737 (a CHK1 inhibitor), and doxorubicin (DOX) for the controlled formation of reactive oxygen species (ROS) and release of DOX and SRA737 upon US activation, therefore increasing chemotherapeutic effectiveness and boosting SDT efficacy. Therein, the antitumor activities of DOX have been attributed to its intercalation into the nucleus DNA and induction of cell apoptosis. CHK1 evolved to respond to DNA damage and repair the damage via cell cycle progression. SRA737 is a potent and orally bioavailable clinical drug candidate for inhibiting CHK1, demonstrating adjuvant anticancer effect in vitro and in vivo. It was interesting to find that SRA737 carried into Plipo@DOX could significantly alleviate G2/M cell cycle arrest and aggravate DNA double-strand injuries, resulting in significant cell death. The developed US-switchable nanosystem provides a promising strategy for augmenting sono-chemotherapy against breast cancer controllably and precisely.


Asunto(s)
Nanopartículas , Neoplasias de la Mama Triple Negativas , Muerte Celular , Línea Celular Tumoral , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Humanos , Liposomas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
13.
Plant Cell Physiol ; 62(9): 1494-1500, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34245304

RESUMEN

Although RNA sequencing (RNAseq) has been becoming the main transcriptomic approach in the model legume Medicago truncatula, there is currently no genome-wide gene expression atlas covering the whole set of RNAseq data published for this species. Nowadays, such a tool is highly valuable to provide a global view of gene expression in a wide range of conditions and tissues/organs. Here, we present MtExpress, a gene expression atlas that compiles an exhaustive set of published M. truncatula RNAseq data (https://medicago.toulouse.inrae.fr/MtExpress). MtExpress makes use of recent releases of M. truncatula genome sequence and annotation, as well as up-to-date tools to perform mapping, quality control, statistical analysis and normalization of RNAseq data. MtExpress combines semi-automated pipelines with manual re-labeling and organization of samples to produce an attractive and user-friendly interface, fully integrated with other available Medicago genomic resources. Importantly, MtExpress is highly flexible, in terms of both queries, e.g. allowing searches with gene names and orthologous gene IDs from Arabidopsis and other legume species, and outputs, to customize visualization and redirect gene study to relevant Medicago webservers. Thanks to its semi-automated pipeline, MtExpress will be frequently updated to follow the rapid pace of M. truncatula RNAseq data publications, as well as the constant improvement of genome annotation. MtExpress also hosts legacy GeneChip expression data originally stored in the Medicago Gene Expression Atlas, as a very valuable and complementary resource.


Asunto(s)
Bases de Datos Genéticas , Genes de Plantas , Medicago truncatula/genética , Transcriptoma , ARN de Planta/genética , Análisis de Secuencia de ARN
14.
Genes Cells ; 25(1): 22-32, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31680384

RESUMEN

DNA methylation controls gene expression, and once established, DNA methylation patterns are faithfully copied during DNA replication by the maintenance DNA methyltransferase Dnmt1. In vivo, Dnmt1 interacts with Uhrf1, which recognizes hemimethylated CpGs. Recently, we reported that Uhrf1-catalyzed K18- and K23-ubiquitinated histone H3 binds to the N-terminal region (the replication focus targeting sequence, RFTS) of Dnmt1 to stimulate its methyltransferase activity. However, it is not yet fully understood how ubiquitinated histone H3 stimulates Dnmt1 activity. Here, we show that monoubiquitinated histone H3 stimulates Dnmt1 activity toward DNA with multiple hemimethylated CpGs but not toward DNA with only a single hemimethylated CpG, suggesting an influence of ubiquitination on the processivity of Dnmt1. The Dnmt1 activity stimulated by monoubiquitinated histone H3 was additively enhanced by the Uhrf1 SRA domain, which also binds to RFTS. Thus, Dnmt1 activity is regulated by catalysis (ubiquitination)-dependent and -independent functions of Uhrf1.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Histonas/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , ADN/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN , Replicación del ADN , Histonas/fisiología , Humanos , Unión Proteica , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
15.
Arch Biochem Biophys ; 711: 109024, 2021 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-34487720

RESUMEN

This study attempted to determine the effect of EphA2 on H2O2-treated lens epithelial cells (SRA01/04) and the underlying mechanisms. MTT assay and flow cytometry were performed to assess cell viability and cell apoptosis. Western blot was carried out to examine the levels of proteins associated with apoptosis and autophagy. Our results revealed that EphA2 significantly elevated the reduced cell viability, and inhibited the increased cell apoptosis in H2O2-treated SRA01/04 cells, along with the significant up-regulated Bcl-2 and down-regulated Cleaved-caspase-3 and Bax protein levels, but which were all abolished by Rapa (autophagy activator). We also found that EphA2 significantly suppressed cell autophagy in H2O2-treated SRA01/04 cells. Additionally, EphA2 significantly up-regulated the protein levels of p-Akt and p-mTOR in H2O2-treated SRA01/04 cells, and the inhibition of Akt by MK-2206 and inhibition of mTOR by Rapa both obviously reversed EphA2-mediated the inhibition of autophagy in H2O2-treated SRA01/04 cells. In summary, these data demonstrated that EphA2 inhibited the apoptosis of SRA01/04 cells by inhibiting autophagy via activating PI3K/Akt/mTOR pathway.


Asunto(s)
Apoptosis/fisiología , Autofagia/fisiología , Receptor EphA2/metabolismo , Transducción de Señal/fisiología , Apoptosis/efectos de los fármacos , Línea Celular , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Humanos , Peróxido de Hidrógeno/farmacología , Cristalino/citología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Regulación hacia Arriba/efectos de los fármacos
16.
Int J Mol Sci ; 22(4)2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33572095

RESUMEN

Long non-coding RNA steroid receptor RNA activators (LncRNA SRAs) are implicated in the ß-cell destruction of Type 1 diabetes mellitus (T1D), but functional association remains poorly understood. Here, we aimed to verify the role of LncRNA SRA regulation in ß-cells. LncRNA SRAs were highly expressed in plasma samples and peripheral blood mononuclear cells (PBMCs) from T1D patients. LncRNA SRA was strongly upregulated by high-glucose treatment. LncRNA SRA acts as a microRNA (miR)-146b sponge through direct sequence-structure interactions. Silencing of lncRNA SRA increased the functional genes of Tregs, resulting in metabolic reprogramming, such as decreased lactate levels, repressed lactate dehydrogenase A (LDHA)/phosphorylated LDHA (pLDHA at Tyr10) expression, decreased reactive oxygen species (ROS) production, increased ATP production, and finally, decreased ß-cell apoptosis in vitro. There was a positive association between lactate level and hemoglobin A1c (HbA1c) level in the plasma from patients with T1D. Recombinant human interleukin (IL)-2 treatment repressed lncRNA SRA expression and activity in ß-cells. Higher levels of lncRNA-SRA/lactate in the plasma are associated with poor regulation in T1D patients. LncRNA SRA contributed to T1D pathogenesis through the inhibition of miR-146b in ß-cells, with activating signaling transduction of interleukin-1 receptor-associated kinase 1 (IRAK1)/LDHA/pLDHA. Taken together, LncRNA SRA plays a critical role in the function of ß-cells.


Asunto(s)
Proteínas Portadoras/genética , Diabetes Mellitus Tipo 1/patología , Células Secretoras de Insulina/patología , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Adolescente , Antagomirs/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/genética , Retroalimentación Fisiológica/efectos de los fármacos , Femenino , Técnicas de Silenciamiento del Gen , Hemoglobina Glucada/análisis , Humanos , Células Secretoras de Insulina/efectos de los fármacos , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Ácido Láctico/metabolismo , Masculino , MicroARNs/agonistas , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , ARN Largo no Codificante/genética , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Activación Transcripcional/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Adulto Joven
17.
J Cell Mol Med ; 24(20): 11729-11741, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32851768

RESUMEN

Lipid deposition in macrophages plays an important role in atherosclerosis. The WNT1-inducible signalling pathway protein 1(WISP1) can promote proliferation and migration of smooth muscle cells. Its expression is up-regulated in obesity, which is associated with atherosclerosis, but the effect of WISP1 on atherosclerosis remains unclear. Thus, the objective of our study was to elucidate the role of WISP and its mechanism of action in atherosclerosis via in vivo and in vitro experiments. In our experiment, ApoE-/- mice were divided into 5 groups: control, high-fat diet (HFD), null lentivirus (HFD + NC), lentivirus WISP1 (HFD + IvWISP1) and WISP1-shRNA (HFD + shWISP1). Oil Red O staining, immunofluorescence and immunohistochemistry of the aortic sinuses were conducted. Macrophages (RAW264.7 cell lines and peritoneal macrophages) were stimulated with 50 µg/mL oxidized low-density lipoprotein (ox-LDL); then, the reactive oxygen species (ROS) level was measured. Oil Red O staining and Dil-ox-LDL (ox-LDL with Dil dye) uptake measurements were used to test lipid deposition of peritoneal macrophages. WISP1, CD36, SR-A and PPARγ expression levels were measured via Western blotting and ELISA. The results showed that HFD mice had increased WISP1, CD36 and SR-A levels. The plaque lesion area increased when WISP1 was down-regulated, and lipid uptake and foam cell formation were inhibited when WISP1 was up-regulated. Treatment of RAW264.7 cell lines with ox-LDL increased WISP1 expression via activation of the Wnt5a/ß-catenin pathway, whereas ROS inhibition reduced WISP1 expression. Moreover, WISP1 down-regulated CD36 and SR-A expression, and Oil Red O staining and Dil-ox-LDL uptake measurement showed that WISP1 down-regulated lipid deposition in macrophages. These results clearly demonstrate that WISP1 is activated by ox-LDL at high ROS levels and can alleviate lipid deposition in atherosclerosis through the PPARγ/CD36 pathway.


Asunto(s)
Proteínas CCN de Señalización Intercelular/metabolismo , Antígenos CD36/metabolismo , Lípidos/química , Macrófagos/metabolismo , PPAR gamma/metabolismo , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patología , Proteínas Proto-Oncogénicas/metabolismo , Transducción de Señal , Animales , Apolipoproteínas E/deficiencia , Apolipoproteínas E/metabolismo , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Lipoproteínas LDL/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo , Vía de Señalización Wnt/efectos de los fármacos
18.
J Biol Chem ; 294(43): 15724-15732, 2019 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-31481468

RESUMEN

The Su(var)3-9, enhancer of zeste, and trithorax (SET) and really interesting new gene (RING) finger-associated (SRA) protein domain is conserved across bacteria and eukaryota and coordinates extrahelical or "flipped" DNA bases. A functional SRA domain is required for ubiquitin-like with PHD and RING finger domains 1 (UHRF1) E3 ubiquitin ligase activity toward histone H3, a mechanism for recruiting the DNA methylation maintenance enzyme DNA methyltransferase 1 (DNMT1). The SRA domain supports UHRF1 oncogenic activity in colon cancer cells, highlighting that UHRF1 SRA antagonism could be a cancer therapeutic strategy. Here we used molecular dynamics simulations, DNA binding assays, in vitro ubiquitination reactions, and DNA methylation analysis to identify the SRA finger loop as a regulator of UHRF1 ubiquitin targeting and DNA methylation maintenance. A chimeric UHRF1 (finger swap) with diminished E3 ligase activity toward nucleosomal histones, despite tighter binding to unmodified or asymmetric or symmetrically methylated DNA, uncouples DNA affinity from regulation of E3 ligase activity. Our model suggests that SRA domains sample DNA bases through flipping in the presence or absence of a cytosine modification and that specific interactions of the SRA finger loop with DNA are required for downstream host protein function. Our findings provide insight into allosteric regulation of UHRF1 E3 ligase activity, suggesting that UHRF1's SRA finger loop regulates its conformation and function.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/química , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Metilación de ADN/genética , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina/metabolismo , Secuencia de Aminoácidos , ADN/química , Células HCT116 , Células HEK293 , Humanos , Fosfatos/metabolismo , Dominios Proteicos , Relación Estructura-Actividad
19.
Mol Pharm ; 17(10): 3794-3812, 2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-32841040

RESUMEN

We have developed a macromolecular prodrug platform based on poly(l-lysine succinylated) (PLS) that targets scavenger receptor A1 (SR-A1), a receptor expressed by myeloid and endothelial cells. We demonstrate the selective uptake of PLS by murine macrophage, RAW 264.7 cells, which was eliminated upon cotreatment with the SR-A inhibitor polyinosinic acid (poly I). Further, we observed no uptake of PLS in an SR-A1-deficient RAW 264.7 cell line, even after 24 h incubation. In mice, PLS distributed to lymphatic organs following i.v. injection, as observed by ex vivo fluorescent imaging, and accumulated in lymph nodes following both i.v. and i.d. administrations, based on immunohistochemical analysis with high-resolution microscopy. As a proof-of-concept, the HIV antiviral emtricitabine (FTC) was conjugated to the polymer's succinyl groups via ester bonds, with a drug loading of 14.2% (wt/wt). The prodrug (PLS-FTC) demonstrated controlled release properties in vitro with a release half-life of 15 h in human plasma and 29 h in esterase-inhibited plasma, indicating that drug release occurs through both enzymatic and nonenzymatic mechanisms. Upon incubation of PLS-FTC with human peripheral blood mononuclear cells (PBMCs), the released drug was converted to the active metabolite FTC triphosphate. In a pharmacokinetic study in rats, the prodrug achieved ∼7-19-fold higher concentrations in lymphatic tissues compared to those in FTC control, supporting lymphatic-targeted drug delivery. We believe that the SR-A1-targeted macromolecular PLS prodrug platform has extraordinary potential for the treatment of infectious diseases.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Portadores de Fármacos/química , Infecciones por VIH/tratamiento farmacológico , Receptores Depuradores de Clase A/metabolismo , Animales , Fármacos Anti-VIH/farmacocinética , Liberación de Fármacos , Emtricitabina/administración & dosificación , Emtricitabina/farmacocinética , Femenino , Semivida , Humanos , Masculino , Ratones , Poli I/farmacología , Polilisina/química , Profármacos/administración & dosificación , Profármacos/farmacocinética , Prueba de Estudio Conceptual , Células RAW 264.7 , Ratas , Receptores Depuradores de Clase A/antagonistas & inhibidores , Receptores Depuradores de Clase A/genética
20.
Risk Anal ; 40(S1): 2240-2262, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33084114

RESUMEN

The 40th Anniversary of the Society for Risk Analysis presents an apt time to step back and review the field of risk communication. In this review, we first evaluate recent debates over the field's current state and future directions. Our takeaway is that efforts to settle on a single, generic version of what constitutes risk communication will be less productive than an open-minded exploration of the multiple forms that comprise today's vibrant interdisciplinary field. We then review a selection of prominent cognitive, cultural, and social risk communication scholarship appearing in the published literature since 2010. Studies on trust in risk communication messengers continued to figure prominently, while new research directions emerged on the opportunities and critical challenges of enhancing transparency and using social media. Research on message attributes explored how conceptual insights particularly relating to framing, affective and emotional responses, and uncertainty might be operationalized to improve message effectiveness. Studies consistently demonstrated the importance of evaluation and how varying single attributes alone is unlikely to achieve desired results. Research on risk communication audiences advanced on risk perception and multiway engagement with notable interest in personal factors such as gender, race, age, and political orientation. We conclude by arguing that the field's interdisciplinary tradition should be further nurtured to drive the next evolutionary phase of risk communication research.

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