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1.
Aging (Albany NY) ; 13(12): 16287-16315, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34230220

RESUMO

N6-methyladenosine (m6A) RNA methylation is associated with malignant tumor progression and is modulated by various m6A RNA methylation regulator proteins. However, its role in endometrial cancer is unclear. In this work, we analyzed sequence, copy number variation, and clinical data obtained from the TCGA database. Expression was validated using real-time quantitative polymerase chain reaction and immunohistochemistry. Changes in m6A RNA methylation regulators were closely related to the clinicopathological stage and prognosis of endometrial cancer. In particular, ZC3H13, YTHDC1, and METTL14 were identified as potential markers for endometrial cancer diagnosis and prognosis. The TIMER algorithm indicated that immune cell infiltration correlated with changes in ZC3H13, YTHDC1, and METTL14 expression. Meanwhile, ZC3H13 or YTHDC1 knockdown promoted the proliferation and invasion of endometrial cancer cells. Through gene enrichment analysis, we constructed a regulatory network in order to explore the potential molecular mechanism involving ZC3H13, YTHDC1, and METTL14. Virtual screening predicted interactions of potential therapeutic compounds with METTL14 and YTHDC1. These findings advance the understanding of RNA epigenetic modifications in endometrial cancer while identifying m6A regulators associated with immune infiltration, prognosis, and potential treatment strategies.


Assuntos
Adenosina/análogos & derivados , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/imunologia , Linfócitos do Interstício Tumoral/imunologia , Adenosina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Variações do Número de Cópias de DNA/genética , Intervalo Livre de Doença , Neoplasias do Endométrio/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Ligantes , Metilação , Pessoa de Meia-Idade , Simulação de Acoplamento Molecular , Mutação/genética , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Prognóstico , Modelos de Riscos Proporcionais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/uso terapêutico , Microambiente Tumoral/imunologia
2.
BMC Genomics ; 22(1): 493, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34210256

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) have been shown to play important roles in the regulation of plant growth and development. Recent transcriptomic analyses have revealed the gene expression profiling in wheat spike development, however, the possible regulatory roles of lncRNAs in wheat spike morphogenesis remain largely unclear. RESULTS: Here, we analyzed the genome-wide profiling of lncRNAs during wheat spike development at six stages, and identified a total of 8,889 expressed lncRNAs, among which 2,753 were differentially expressed lncRNAs (DE lncRNAs) at various developmental stages. Three hundred fifteen differentially expressed cis- and trans-regulatory lncRNA-mRNA pairs comprised of 205 lncRNAs and 279 genes were predicted, which were found to be mainly involved in the stress responses, transcriptional and enzymatic regulations. Moreover, the 145 DE lncRNAs were predicted as putative precursors or target mimics of miRNAs. Finally, we identified the important lncRNAs that participate in spike development by potentially targeting stress response genes, TF genes or miRNAs. CONCLUSIONS: This study outlines an overall view of lncRNAs and their possible regulatory networks during wheat spike development, which also provides an alternative resource for genetic manipulation of wheat spike architecture and thus yield.


Assuntos
MicroRNAs , RNA Longo não Codificante , Perfilação da Expressão Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro , Triticum/genética
3.
Anticancer Res ; 41(7): 3583-3588, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34230154

RESUMO

BACKGROUND/AIM: This study aimed to evaluate the prognostic significance of PLA2G2A expression in patients with locally advanced gastric cancer (GC). PATIENTS AND METHODS: PLA2G2A expression levels in cancerous tissue specimens and adjacent normal mucosa obtained from 134 patients with stage II/III GC who received adjuvant chemotherapy with S-1 after curative resection were measured using real-time quantitative polymerase chain reaction. Subsequently, the associations of PLA2G2A expression with clinicopathological features and survival were evaluated. RESULTS: No association was observed between clinicopathological features and PLA2G2A expression levels. Overall survival was significantly longer in patients with high PLA2G2A expression levels (p=0.022). Multivariate analysis revealed that PLA2G2A expression was a significant, independent prognostic factor (hazard ratio=0.136; 95% confidence interval=0.0185-0.992; p=0.049). CONCLUSION: PLA2G2A mRNA expression may serve as a useful prognostic marker in patients with locally advanced GC who receive curative surgery and adjuvant chemotherapy with S-1.


Assuntos
Fosfolipases A2 do Grupo II/metabolismo , Ácido Oxônico/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Tegafur/uso terapêutico , Idoso , Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante/métodos , Combinação de Medicamentos , Feminino , Gastrectomia/métodos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Masculino , Estadiamento de Neoplasias/métodos , Prognóstico , RNA Mensageiro/metabolismo , Estômago/efeitos dos fármacos , Estômago/patologia , Estômago/cirurgia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
4.
Anticancer Res ; 41(7): 3597-3606, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34230156

RESUMO

AIM: To evaluate the association between bromodomain-containing protein 4 (BRD4) expression and clinicopathological factors and prognosis in human breast cancer specimens. PATIENTS AND METHODS: We used tissue microarrays constructed from samples of patients (n=183) who underwent surgery. We validated the association between BRD4 expression and prognosis in solid tumours, including breast cancer, using The Cancer Genome Atlas (TCGA) database. RESULTS: Immunohistochemical staining showed that BRD4 was widely distributed in breast cancer tissues. BRD4 was strongly expressed in 19.7% of patients but BRD4 staining intensity was not correlated with other clinicopathological factors. Most importantly, patients with a strong BRD4 expression had a significantly longer disease-specific survival than those with a weak BRD4 expression (100.0% vs. 91.3% at 5 years, p=0.027). mRNA expression analysis showed similar results (91.2% vs. 80.2% at 6 years, p=0.047). CONCLUSION: Strong BRD4 expression was associated with a significantly better prognosis in breast cancer tumours.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/metabolismo , Fatores de Transcrição/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/metabolismo
5.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198485

RESUMO

Brain microvascular endothelial cells (BMECs) constitute the structural and functional basis for the blood-brain barrier (BBB) and play essential roles in bacterial meningitis. Although the BBB integrity regulation has been under extensive investigation, there is little knowledge regarding the roles of long non-coding RNAs (lncRNAs) in this event. The present study aimed to investigate the roles of one potential lncRNA, lncRSPH9-4, in meningitic E. coli infection of BMECs. LncRSPH9-4 was cytoplasm located and significantly up-regulated in meningitic E. coli-infected hBMECs. Electrical cell-substrate impedance sensing (ECIS) measurement and Western blot assay demonstrated lncRSPH9-4 overexpression in hBMECs mediated the BBB integrity disruption. By RNA-sequencing analysis, 639 mRNAs and 299 miRNAs were significantly differentiated in response to lncRSPH9-4 overexpression. We further found lncRSPH9-4 regulated the permeability in hBMECs by competitively sponging miR-17-5p, thereby increasing MMP3 expression, which targeted the intercellular tight junctions. Here we reported the infection-induced lncRSPH9-4 aggravated disruption of the tight junctions in hBMECs, probably through the miR-17-5p/MMP3 axis. This finding provides new insights into the function of lncRNAs in BBB integrity during meningitic E. coli infection and provides the novel nucleic acid targets for future treatment of bacterial meningitis.


Assuntos
Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Escherichia coli/fisiologia , Metaloproteinase 3 da Matriz/metabolismo , Meningites Bacterianas/genética , Meningites Bacterianas/microbiologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Sequência de Bases , Citoplasma/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , Microvasos/patologia , Modelos Biológicos , Permeabilidade , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Junções Íntimas/metabolismo , Transcrição Genética , Regulação para Cima/genética
6.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198626

RESUMO

Human stem-cell factor (hSCF) stimulates the survival, proliferation, and differentiation of hematopoietic cells by binding to the c-Kit receptor. Various applications of hSCF require the efficient and reliable production of hSCF. hSCF exists in three forms: as two membrane-spanning proteins hSCF248 and hSCF229 and truncated soluble N-terminal protein hSCF164. hSCF164 is known to be insoluble when expressed in Escherichia coli cytoplasm, requiring a complex refolding procedure. The activity of hSCF248 has never been studied. Here, we investigated novel production methods for recombinant hSCF164 and hSCF248 without the refolding process. To increase the solubility of hSCF164, maltose-binding protein (MBP) and protein disulfide isomerase b'a' domain (PDIb'a') tags were attached to the N-terminus of hSCF164. These fusion proteins were overexpressed in soluble form in the Origami 2(DE3) E. coli strain. These solubilization effects were enhanced at a low temperature. His-hSCF248, the poly-His tagged form of hSCF248, was expressed in a highly soluble form without a solubilization tag protein, which was unexpected because His-hSCF248 contains a transmembrane domain. hSCF164 was purified using affinity and ion-exchange chromatography, and His-hSCF248 was purified by ion-exchange and gel filtration chromatography. The purified proteins stimulated the proliferation of TF-1 cells. Interestingly, the EC50 value of His-hSCF248 was 1 pg/mL, 100-fold lower than 9 ng/mL hSCF164. Additionally, His-hSCF248 decreased the doubling time, increased the proportion of S and G2/M stages in the cell cycle, and increased the c-Myc expression at a 1000-fold lower concentration than hSCF164. In conclusion, His-hSCF248 was expressed in a soluble form in E. coli and had stronger activity than hSCF164. The molecular chaperone, MBP, enabled the soluble overexpression of hSCF164.


Assuntos
Fator de Células-Tronco/biossíntese , Sequência de Aminoácidos , Ciclo Celular , Proliferação de Células , Regulação da Expressão Gênica , Humanos , Plasmídeos/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade , Fator de Células-Tronco/química
7.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203850

RESUMO

Steroid receptor coactivator-1 (SRC-1) is a transcription coactivator playing a pivotal role in mediating a wide range of signaling pathways by interacting with related transcription factors and nuclear receptors. Aberrantly elevated SRC-1 activity is associated with cancer metastasis and progression, and therefore, suppression of SRC-1 is emerging as a promising therapeutic strategy. In this study, we developed a novel SRC-1 degrader for targeted degradation of cellular SRC-1. This molecule consists of a selective ligand for SRC-1 and a bulky hydrophobic group. Since the hydrophobic moiety on the protein surface could mimic a partially denatured hydrophobic region of a protein, SRC-1 could be recognized as an unfolded protein and experience the chaperone-mediated degradation in the cells through the ubiquitin-proteasome system (UPS). Our results demonstrate that a hydrophobic-tagged chimeric molecule is shown to significantly reduce cellular levels of SRC-1 and suppress cancer cell migration and invasion. Together, these results highlight that our SRC-1 degrader represents a novel class of therapeutic candidates for targeting cancer metastasis. Moreover, we believe that the hydrophobic tagging strategy would be widely applicable to develop peptide-based protein degraders with enhanced cellular activity.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Coativador 1 de Receptor Nuclear/metabolismo , Proteólise , Transativadores/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Movimento Celular , Humanos , Fator Estimulador de Colônias de Macrófagos/genética , Fator Estimulador de Colônias de Macrófagos/metabolismo , Chaperonas Moleculares/metabolismo , Invasividade Neoplásica , Peptídeos/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Estabilidade Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
9.
Front Immunol ; 12: 625732, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194422

RESUMO

The etiological agent of COVID-19 SARS-CoV-2, is primarily a pulmonary-tropic coronavirus. Infection of alveolar pneumocytes by SARS-CoV-2 requires virus binding to the angiotensin I converting enzyme 2 (ACE2) monocarboxypeptidase. ACE2, present on the surface of many cell types, is known to be a regulator of blood pressure homeostasis through its ability to catalyze the proteolysis of Angiotensin II (Ang II) into Angiotensin-(1-7) [Ang-(1-7)]. We therefore hypothesized that SARS-CoV-2 could trigger variations of ACE2 expression and Ang II plasma concentration in SARS-CoV-2-infected patients. We report here, that circulating blood cells from COVID-19 patients express less ACE2 mRNA than cells from healthy volunteers. At the level of circulating cells, this ACE2 gene dysregulation mainly affects the monocytes, which also show a lower expression of membrane ACE2 protein. Moreover, soluble ACE2 (sACE2) plasma concentrations are lower in prolonged viral shedders than in healthy controls, while the concentration of sACE2 returns to normal levels in short viral shedders. In the plasma of prolonged viral shedders, we also found higher concentrations of Ang II and angiotensin I (Ang I). On the other hand, the plasma levels of Ang-(1-7) remains almost stable in prolonged viral shedders but seems insufficient to prevent the adverse effects of Ang II accumulation. Altogether, these data evidence that the SARS-CoV-2 may affect the expression of blood pressure regulators with possible harmful consequences on COVID-19 outcome.


Assuntos
Angiotensina II/sangue , Angiotensina I/sangue , Enzima de Conversão de Angiotensina 2/sangue , COVID-19/sangue , Fragmentos de Peptídeos/sangue , Adulto , Enzima de Conversão de Angiotensina 2/genética , COVID-19/virologia , Feminino , Perfilação da Expressão Gênica , Antígenos HLA-DR , Humanos , Receptores de Lipopolissacarídeos , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Projetos Piloto , Estudos Prospectivos , RNA Mensageiro , Eliminação de Partículas Virais
10.
Elife ; 102021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34213415

RESUMO

Longer poly(A) tails improve translation in early development, but not in mature cells that have higher levels of the protein PABPC.


Assuntos
Oócitos , RNA Mensageiro
12.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204574

RESUMO

Using TSG101 pre-mRNA, we previously discovered cancer-specific re-splicing of mature mRNA that generates aberrant transcripts/proteins. The fact that mRNA is aberrantly re-spliced in various cancer cells implies there must be an important mechanism to prevent deleterious re-splicing on the spliced mRNA in normal cells. We thus postulated that mRNA re-splicing is controlled by specific repressors, and we searched for repressor candidates by siRNA-based screening for mRNA re-splicing activity. We found that knock-down of EIF4A3, which is a core component of the exon junction complex (EJC), significantly promoted mRNA re-splicing. Remarkably, we could recapitulate cancer-specific mRNA re-splicing in normal cells by knock-down of any of the core EJC proteins, EIF4A3, MAGOH, or RBM8A (Y14), implicating the EJC core as the repressor of mRNA re-splicing often observed in cancer cells. We propose that the EJC core is a critical mRNA quality control factor to prevent over-splicing of mature mRNA.


Assuntos
Éxons , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Precursores de RNA/genética , Splicing de RNA , RNA Mensageiro/genética , Linhagem Celular Tumoral , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , Humanos , Modelos Biológicos , Neoplasias/metabolismo , Ligação Proteica , Transporte de RNA , Proteínas de Ligação a RNA/metabolismo
13.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204585

RESUMO

In this study, we explored expression of microRNA (miR), miR-target genes and matrix remodelling molecules in temporal artery biopsies (TABs) from treatment-naïve patients with giant cell arteritis (GCA, n = 41) and integrated these analyses with clinical, laboratory, ultrasound and histological manifestations of GCA. NonGCA patients (n = 4) served as controls. GCA TABs exhibited deregulated expression of several miRs (miR-21-5p, -145-5p, -146a-5p, -146b-5p, -155-5p, 424-3p, -424-5p, -503-5p), putative miR-target genes (YAP1, PELI1, FGF2, VEGFA, KLF4) and matrix remodelling factors (MMP2, MMP9, TIMP1, TIPM2) with key roles in Toll-like receptor signaling, mechanotransduction and extracellular matrix biology. MiR-424-3p, -503-5p, KLF4, PELI1 and YAP1 were identified as new deregulated molecular factors in GCA TABs. Quantities of miR-146a-5p, YAP1, PELI1, FGF2, TIMP2 and MMP9 were particularly high in histologically positive GCA TABs with occluded temporal artery lumen. MiR-424-5p expression in TABs and the presence of facial or carotid arteritis on ultrasound were associated with vision disturbances in GCA patients. Correlative analysis of miR-mRNA quantities demonstrated a highly interrelated expression network of deregulated miRs and mRNAs in temporal arteries and identified KLF4 as a candidate target gene of deregulated miR-21-5p, -146a-5p and -155-5p network in GCA TABs. Meanwhile, arterial miR and mRNA expression did not correlate with constitutive symptoms and signs of GCA, elevated markers of systemic inflammation nor sonographic characteristics of GCA. Our study provides new insights into GCA pathophysiology and uncovers new candidate biomarkers of vision impairment in GCA.


Assuntos
Regulação da Expressão Gênica , Redes Reguladoras de Genes , Arterite de Células Gigantes/etiologia , Arterite de Células Gigantes/metabolismo , MicroRNAs/genética , Interferência de RNA , RNA Mensageiro/genética , Artérias Temporais/metabolismo , Biomarcadores , Biópsia , Suscetibilidade a Doenças , Perfilação da Expressão Gênica , Arterite de Células Gigantes/diagnóstico , Humanos , Imuno-Histoquímica , Avaliação de Sintomas , Artérias Temporais/patologia , Ultrassonografia
14.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204592

RESUMO

NADH dehydrogenase (ubiquinone) Fe-S protein 8 (NDUFS8) is a nuclear-encoded core subunit of human mitochondrial complex I. Defects in NDUFS8 are associated with Leigh syndrome and encephalomyopathy. Cell-penetrating peptide derived from the HIV-1 transactivator of transcription protein (TAT) has been successfully applied as a carrier to bring fusion proteins into cells without compromising the biological function of the cargoes. In this study, we developed a TAT-mediated protein transduction system to rescue complex I deficiency caused by NDUFS8 defects. Two fusion proteins (TAT-NDUFS8 and NDUFS8-TAT) were exogenously expressed and purified from Escherichia coli for transduction of human cells. In addition, similar constructs were generated and used in transfection studies for comparison. The results showed that both exogenous TAT-NDUFS8 and NDUFS8-TAT were delivered into mitochondria and correctly processed. Interestingly, the mitochondrial import of TAT-containing NDUFS8 was independent of mitochondrial membrane potential. Treatment with TAT-NDUFS8 not only significantly improved the assembly of complex I in an NDUFS8-deficient cell line, but also partially rescued complex I functions both in the in-gel activity assay and the oxygen consumption assay. Our current findings suggest the considerable potential of applying the TAT-mediated protein transduction system for treatment of complex I deficiency.


Assuntos
Complexo I de Transporte de Elétrons/deficiência , Potencial da Membrana Mitocondrial , Mitocôndrias/genética , Mitocôndrias/metabolismo , NADH Desidrogenase/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Sequência de Aminoácidos , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , NADH Desidrogenase/genética , Transporte Proteico , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
15.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199774

RESUMO

Over a thousand nucleus-encoded mitochondrial proteins are imported from the cytoplasm; however, mitochondrial (mt) DNA encodes for a small number of critical proteins and the entire suite of mt:tRNAs responsible for translating these proteins. Mitochondrial RNase P (mtRNase P) is a three-protein complex responsible for cleaving and processing the 5'-end of mt:tRNAs. Mutations in any of the three proteins can cause mitochondrial disease, as well as mutations in mitochondrial DNA. Great strides have been made in understanding the enzymology of mtRNase P; however, how the loss of each protein causes mitochondrial dysfunction and abnormal mt:tRNA processing in vivo has not been examined in detail. Here, we used Drosophila genetics to selectively remove each member of the complex in order to assess their specific contributions to mt:tRNA cleavage. Using this powerful model, we find differential effects on cleavage depending on which complex member is lost and which mt:tRNA is being processed. These data revealed in vivo subtleties of mtRNase P function that could improve understanding of human diseases.


Assuntos
Mitocôndrias/enzimologia , Processamento Pós-Transcricional do RNA/genética , RNA de Transferência/genética , Ribonuclease P/metabolismo , Alelos , Animais , Drosophila melanogaster/genética , Mitocôndrias/patologia , Mutação/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Transferência/metabolismo
16.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205604

RESUMO

Rutin (R) and quercetin (Q) are two widespread dietary flavonoids. Previous studies regarding the plasma cholesterol-lowering activity of R and Q generated inconsistent results. The present study was therefore carried out to investigate the effects of R and Q on cholesterol metabolism in both HepG2 cells and hypercholesterolemia hamsters. Results from HepG2 cell experiments demonstrate that both R and Q decreased cholesterol at doses of 5 and 10 µM. R and Q up-regulated both the mRNA and protein expression of sterol regulatory element binding protein 2 (SREBP2), low-density lipoprotein receptor (LDLR), and liver X receptor alpha (LXRα). The immunofluorescence study revealed that R and Q increased the LDLR expression, while only Q improved LDL-C uptake in HepG2 cells. Results from hypercholesterolemia hamsters fed diets containing R (5.5 g/kg diet) and Q (2.5 g/kg diet) for 8 weeks demonstrate that both R and Q had no effect on plasma total cholesterol. In the liver, only Q reduced cholesterol significantly. The discrepancy between the in vitro and in vivo studies was probably due to a poor bioavailability of flavonoids in the intestine. It was therefore concluded that R and Q were effective in reducing cholesterol in HepG2 cells in vitro, whereas in vivo, the oral administration of the two flavonoids had little effect on plasma cholesterol in hamsters.


Assuntos
Colesterol/sangue , Colesterol/metabolismo , Quercetina/farmacologia , Rutina/farmacologia , Administração Oral , Animais , Linhagem Celular Tumoral , Cricetinae , Flavonoides/farmacologia , Células Hep G2 , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Receptores X do Fígado/metabolismo , Masculino , RNA Mensageiro/metabolismo , Receptores de LDL/sangue , Receptores de LDL/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Regulação para Cima/efeitos dos fármacos
17.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208095

RESUMO

Signal recognition particle (SRP) is an RNA and protein complex that exists in all domains of life. It consists of one protein and one noncoding RNA in some bacteria. It is more complex in eukaryotes and consists of six proteins and one noncoding RNA in mammals. In the eukaryotic cytoplasm, SRP co-translationally targets proteins to the endoplasmic reticulum and prevents misfolding and aggregation of the secretory proteins in the cytoplasm. It was demonstrated recently that SRP also possesses an earlier unknown function, the protection of mRNAs of secretory proteins from degradation. In this review, we analyze the progress in studies of SRPs from different organisms, SRP biogenesis, its structure, and function in protein targeting and mRNA protection.


Assuntos
Biossíntese de Proteínas , Partícula de Reconhecimento de Sinal/metabolismo , Animais , Evolução Molecular , Humanos , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Partícula de Reconhecimento de Sinal/química
18.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208159

RESUMO

B-cell lymphoma 2 (Bcl-2) and cytochrome c (Cycs) are two important proteins relevant to cellular apoptosis. In this study, we characterized the functions of the promoter regions of two apoptosis-related genes, Bcl-2 and Cycs, in yellow catfish Pelteobagrus fulvidraco. We obtained a 1989 bp Bcl-2 promoter and an 1830 bp Cycs promoter and predicted several key transcription factor binding sites (TFBSs) on the promoters, such as Kruppel-like factor 4 (KLF4), signal transducer and activator of transcription factor 3 (STAT3), forkhead box O (FOXO), metal-responsive element (MRE) and hepatocyte nuclear factor 1α (HNF-1α). Zinc (Zn) increased the activities of the Bcl-2 promoter but decreased the activities of the Cycs promoter. Metal-responsive transcription factor 1 (MTF-1) and HNF-1α directly bound with Bcl-2 and Cycs promoters, and they positively regulated the activity of the Bcl-2 promoter but negatively regulated the activity of the Cycs promoter. Zn promoted the binding ability of HNF-1α to the Bcl-2 promoter but decreased its binding ability to the Cycs promoter. However, Zn had no significant effect on the binding capability of MTF-1 to the regions of Bcl-2 and Cycs promoters. Zn upregulated the mRNA and total protein expression of Bcl-2 but downregulated the mRNA and total protein expression of Cycs. At the same time, Annexin V-FITC/PI staining showed that Zn significantly reduced the apoptosis of primary hepatocytes. For the first time, our study provides evidence for the MRE and HNF-1α response elements on the Bcl-2 and Cycs promoters, offering new insight into the mechanism by which Zn affects apoptosis in vertebrates.


Assuntos
Apoptose/genética , Peixes-Gato/genética , Citocromos c/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-bcl-2/genética , Zinco/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sequência de Bases , Sítios de Ligação , Citocromos c/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Deleção de Sequência
19.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208173

RESUMO

Maternal malnutrition in critical periods of development increases the risk of developing short- and long-term diseases in the offspring. The alterations induced by this nutritional programming in the hypothalamus of the offspring are of special relevance due to its role in energy homeostasis, especially in the endocannabinoid system (ECS), which is involved in metabolic functions. Since astrocytes are essential for neuronal energy efficiency and are implicated in brain endocannabinoid signaling, here we have used a rat model to investigate whether a moderate caloric restriction (R) spanning from two weeks prior to the start of gestation to its end induced changes in offspring hypothalamic (a) ECS, (b) lipid metabolism (LM) and/or (c) hypothalamic astrocytes. Monitorization was performed by analyzing both the gene and protein expression of proteins involved in LM and ECS signaling. Offspring born from caloric-restricted mothers presented hypothalamic alterations in both the main enzymes involved in LM and endocannabinoids synthesis/degradation. Furthermore, most of these changes were similar to those observed in hypothalamic offspring astrocytes in culture. In conclusion, a maternal low caloric intake altered LM and ECS in both the hypothalamus and its astrocytes, pointing to these glial cells as responsible for a large part of the alterations seen in the total hypothalamus and suggesting a high degree of involvement of astrocytes in nutritional programming.


Assuntos
Astrócitos/metabolismo , Restrição Calórica , Endocanabinoides/metabolismo , Hipotálamo/metabolismo , Metabolismo dos Lipídeos , Transdução de Sinais , Animais , Animais Recém-Nascidos , Peso Corporal , Encéfalo/patologia , Feminino , Regulação da Expressão Gênica , Gliose/genética , Gliose/patologia , Inflamação/genética , Inflamação/patologia , Metabolismo dos Lipídeos/genética , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais/genética
20.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208198

RESUMO

The role of auxin in the fruit-ripening process during the early developmental stages of commercial strawberry fruits (Fragaria x ananassa) has been previously described, with auxin production occurring in achenes and moving to the receptacle. Additionally, fruit softening is a consequence of the depolymerization and solubilization of cell wall components produced by the action of a group of proteins and enzymes. The aim of this study was to compare the effect of exogenous auxin treatment on the physiological properties of the cell wall-associated polysaccharide contents of strawberry fruits. We combined thermogravimetric (TG) analysis with analyses of the mRNA abundance, enzymatic activity, and physiological characteristics related to the cell wall. The samples did not show a change in fruit firmness at 48 h post-treatment; by contrast, we showed changes in the cell wall stability based on TG and differential thermogravimetric (DTG) analysis curves. Less degradation of the cell wall polymers was observed after auxin treatment at 48 h post-treatment. The results of our study indicate that auxin treatment delays the cell wall disassembly process in strawberries.


Assuntos
Biopolímeros/metabolismo , Parede Celular/metabolismo , Fragaria/metabolismo , Frutas/metabolismo , Ácidos Indolacéticos/farmacologia , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Fragaria/efeitos dos fármacos , Fragaria/genética , Frutas/efeitos dos fármacos , Frutas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Temperatura , Termogravimetria , Transcrição Genética/efeitos dos fármacos , Ácidos Tri-Iodobenzoicos/farmacologia
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