RESUMO
Fluoride (F) and sulfur dioxide (SO2) contamination is recognized as a public health concern worldwide. Our previous research has shown that Co-exposure to F and SO2 can cause abnormal enamel mineralization. Ameloblastin (AMBN) plays a crucial role in the process of enamel mineralization. However, the process by which simultaneous exposure to F and SO2 influences enamel formation by regulating AMBN expression still needs to be understood. This study aimed to establish in vivo and in vitro models of F-SO2 Co-exposure and investigate the relationship between AMBN and abnormal enamel mineralization. By overexpressing/knocking out the Fibroblast Growth Factor 9 (FGF9) gene, we investigated the impact of FGF9-mediated Mitogen-Activated Protein Kinase (MAPK) signaling on AMBN synthesis to elucidate the mechanism underlying the induction of abnormal enamel mineralization by F-SO2 Co-exposure in rats. The results showed that F-SO2 exposure damaged the structure of rat enamel and ameloblasts. When exposed to F or SO2, gradual increases in the protein expression of FGF9 and phosphorylated p38 mitogen-activated protein kinase (p-P38) were observed. Conversely, the protein levels of AMBN, phosphorylated extracellular signal-regulated kinase (p-ERK), and phosphorylated c-Jun N-terminal kinase (p-JNK) were decreased. AMBN expression was significantly correlated with FGF9, p-ERK, and p-JNK expression in ameloblasts. Interestingly, FGF9 overexpression reduced the levels of p-ERK and p-JNK, worsening the inhibitory effect of F-SO2 on AMBN. Conversely, FGF9 knockout increased the phosphorylation of ERK and JNK, partially reversing the F-SO2-induced downregulation of AMBN. Taken together, these findings strongly demonstrate that FGF9 plays a critical role in F-SO2-induced abnormal enamel mineralization by regulating AMBN synthesis through the JNK and ERK pathways.
Assuntos
Esmalte Dentário , Fator 9 de Crescimento de Fibroblastos , Fluoretos , Sistema de Sinalização das MAP Quinases , Dióxido de Enxofre , Animais , Fator 9 de Crescimento de Fibroblastos/genética , Fator 9 de Crescimento de Fibroblastos/metabolismo , Ratos , Fluoretos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Esmalte Dentário/efeitos dos fármacos , Dióxido de Enxofre/toxicidade , Masculino , Ratos Sprague-Dawley , Proteínas do Esmalte Dentário/genética , Proteínas do Esmalte Dentário/metabolismo , Calcificação de Dente/efeitos dos fármacos , Ameloblastos/efeitos dos fármacos , Ameloblastos/metabolismoRESUMO
Cytosolic DNA activates cGAS (cytosolic DNA sensor cyclic AMP-GMP synthase)-STING (stimulator of interferon genes) signaling, which triggers interferon and inflammatory responses that help defend against microbial infection and cancer. However, aberrant cytosolic self-DNA in Aicardi-Goutière's syndrome and constituently active gain-of-function mutations in STING in STING-associated vasculopathy with onset in infancy (SAVI) patients lead to excessive type I interferons and proinflammatory cytokines, which cause difficult-to-treat and sometimes fatal autoimmune disease. Here, in silico docking identified a potent STING antagonist SN-011 that binds with higher affinity to the cyclic dinucleotide (CDN)-binding pocket of STING than endogenous 2'3'-cGAMP. SN-011 locks STING in an open inactive conformation, which inhibits interferon and inflammatory cytokine induction activated by 2'3'-cGAMP, herpes simplex virus type 1 infection, Trex1 deficiency, overexpression of cGAS-STING, or SAVI STING mutants. In Trex1-/- mice, SN-011 was well tolerated, strongly inhibited hallmarks of inflammation and autoimmunity disease, and prevented death. Thus, a specific STING inhibitor that binds to the STING CDN-binding pocket is a promising lead compound for STING-driven disease.
Assuntos
Proteínas de Membrana/antagonistas & inibidores , Nucleotídeos Cíclicos/metabolismo , Animais , Sítios de Ligação , Biotinilação , Morte Celular , Exodesoxirribonucleases/deficiência , Humanos , Inflamação/patologia , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Mutação/genética , Fosfoproteínas/deficiência , Domínios Proteicos , Transdução de SinaisRESUMO
BACKGROUND: Myoglobin (MB), a pigmentation protein, can adversely affect the antibacterial activity of carvacrol (CAR) and weaken its bacteriostasis effect. This study aimed to clarify the influence of MB on the antibacterial activity of CAR and ascertain the mechanism involved in the observed influence, especially the interaction between the two compounds. RESULTS: Microbiological analysis indicated that the presence of MB significantly suppressed the antibacterial activity of CAR against Listeria monocytogenes. Ultraviolet-visible spectrometry and fluorescence spectroscopic analysis confirmed the interaction between CAR and MB. The stoichiometric number was determined as ~0.7 via double logarithmic Stern-Volmer equation analysis, while thermodynamic analysis showed that the conjugation of the two compounds occurred as an exothermal reaction (ΔH° = -32.3 ± 11.4 kJ mol-1 and ΔS° = -75 J mol-1 K-1 ). Circular dichroism, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy showed hydrogen bonding in the carvacrol-myoglobin complex (CAR-MB). Molecular docking analysis confirmed that amino acid residues, including GLY80 and HIS82, were most likely to form hydrogen bonds with CAR, while hydrogen bonds represented the main driving force for CAR-MB formation. CONCLUSION: CAR antibacterial activity was significantly inhibited by the presence of MB in the environment due to the notable reduction in the effective concentration of CAR caused by CAR-MB formation. © 2023 Society of Chemical Industry.
Assuntos
Antibacterianos , Mioglobina , Simulação de Acoplamento Molecular , Mioglobina/química , Espectrometria de Fluorescência , Ligação Proteica , Termodinâmica , Antibacterianos/farmacologia , Dicroísmo Circular , Sítios de Ligação , Espectroscopia de Infravermelho com Transformada de Fourier/métodosRESUMO
Many geographical areas of the world are polluted by both fluoride and sulfur dioxide (SO2). However, the effects of simultaneous exposure to fluoride and SO2 on teeth are unknown. Fibroblast growth factor-9 (FGF9) and transforming growth factor-ß1 (TGF-ß1) are key signaling molecules in enamel development. The purpose of the study was to explore the effects of co-exposure to fluoride and sulfur dioxide on enamel and to investigate the role and mechanism of FGF9 and TGF-ß1. First, sodium fluoride (NaF) and SO2 derivatives were used to construct rat models and evaluate the enamel development of rats. Then, TGF-ß1 (cytokine) treatment, SIS3 (inhibitor) treatment and FGF9 gene knockdown were used to explore the mechanism of enamel damage in vitro. The results showed that enamel column crystals in the exposed group were characterized by enamel hypoplasia, as indicated by alterations such as disarrangement of enamel column crystals, space widening and breakage. Ameloblasts also showed pathological changes such as ribosome loss, mitochondrial swelling, nuclear fragmentation and chromatin aggregation. The protein expression of FGF9 was higher and the protein expression of AMBN, TGF-ß1 and p-Smad2/3 protein was lower in the groups treated with fluoride and SO2 individually or in combination compared with the control group. Further studies showed that TGF-ß1 significantly upregulated p-Smad2/3 and AMBN protein expression and reduced the inhibitory effects of fluoride and SO2; furthermore, SISI blocked the effect of TGF-ß1. In addition, knockdown of FGF9 upregulated TGF-ß1 protein expression, further activated Smad2/3 phosphorylation, eliminated the inhibitory effects of fluoride and SO2, and increased the protein expression of AMBN. In brief, the study confirms that co-exposure to fluoride and SO2 can result in enamel hypoplasia in rats and indicates that the underlying mechanism may be closely related to the effect of FGF9 on enamel matrix protein secretion through inhibition of the TGF-ß1/Smad signaling pathway.
Assuntos
Hipoplasia do Esmalte Dentário , Fator de Crescimento Transformador beta1 , Ratos , Animais , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fluoretos/farmacologia , Dióxido de Enxofre/farmacologia , Transdução de SinaisRESUMO
Pachymic acid, a well-known natural lanostane-type triterpenoid, exhibits various pharmacological properties. In this study, 18 derivatives of pachymic acid were synthesized by modifying their molecular structures and evaluated for their anticancer activity against two human cancer cell lines using the CCK-8 assay. Structure-activity relationship studies according to the in vitro cytotoxicity unexpectedly found one promising derivative A17 (namely tumulosic acid, also found in Poria cocos), which had stronger anti-proliferative activity than the positive drug cisplatin against HepG2 and HSC-2 cell lines with IC50 values of 7.36 ± 0.98 and 2.50 ± 0.15 µM, respectively. Further pharmacological analysis demonstrated that A17 induced HSC-2 cell cycle arrest at the S phase, cell apoptosis, and autophagy. Western blotting confirmed the regulatory effects of A17 on cell cycle arrest-, apoptosis-, and autophagy-related proteins expression. In addition, A17 regulated the AKT and AMPK pathways in HSC-2 cells. These results demonstrated that A17 possesses great potential as an anticancer agent.
RESUMO
Sulphur dioxide (SO2) and fluoride are among the most common environmental pollutants affecting human health, and both co-exist in areas predominantly consuming coal. It is vital to analyse the combined toxicity of SO2 and fluoride, and their effects on health and the underlying mechanisms of their co-exposure have not yet been adequately assessed. In the present study, we used ICR mice and LS8 cells to investigate the toxicity of SO2 and fluoride exposure to the enamel, alone or in combination. Factorial design analysis was used to reveal the combined toxicity in vitro and in vivo. Co-exposure to SO2 and fluoride exacerbated enamel injury, resulting in more severe hypomineralization of incisor, and enamel structure disorders in mice, and could induce the accumulation of protein residue in the matrix of the enamel. Amelogenin expression was increased upon exposure to SO2 and fluoride, but enamel matrix proteases were not affected. Consistent with our in vivo results, co-exposure of SO2 and fluoride aggravated amelogenin expression in LS8 cells, and increased the YAP and RUNX2 levels. Co-exposure to SO2 and fluoride resulted in greater toxicity than individual exposure, both in vitro and in vivo, indicating that residents of areas exposed to SO2 and fluoride may have an increased risk of developing enamel damage.
Assuntos
Poluentes Ambientais , Fluoretos , Amelogenina , Animais , Carvão Mineral , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Poluentes Ambientais/farmacologia , Fluoretos/toxicidade , Humanos , Incisivo , Camundongos , Camundongos Endogâmicos ICR , Peptídeo Hidrolases , Transdução de Sinais , Dióxido de Enxofre/toxicidade , Regulação para Cima , Proteínas de Sinalização YAPRESUMO
Herein, we evaluated the potential therapeutic effects of water extracts from Eucommia on periodontitis in experimental rats. We ligated the maxillary second molars of Sprague-Dawley(SD) rats with 4.0 silk threads and locally smeared Porphyromonas gingivalis(P. gingivalis) to induce gingivitis and periodontitis.After the model was successfully established, we exposed the rats to Eucommia water extracts through topical smearing and intragastric administration and evaluated the therapeutic effect of the extracts on gingivitis (for a 2 week treatment period) and periodontitis (over 4 weeks). We analyzed histopathological sections of the periodontal tissue and quantified the alveolar bone resorption levels, molecules related to periodontal oxidative stress, and periodontal inflammatory factors to assess the feasibility of Eucommia in treating gingivitis and periodontitis. We found that damage to the periodontal tissue was reduced after treatment with extracts,indicating that Eucommia has a positive effect in treating gingivitis and periodontitis in experimental rats. These findings are expected to provide the foothold for future research on secondary metabolites derived from Eucommia and guide the development of novel approaches for preventing and treating periodontal disease.
Assuntos
Perda do Osso Alveolar , Gengivite , Periodontite , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/prevenção & controle , Animais , Gengivite/tratamento farmacológico , Gengivite/prevenção & controle , Periodontite/complicações , Periodontite/tratamento farmacológico , Periodontite/prevenção & controle , Porphyromonas gingivalis , Ratos , Ratos Sprague-Dawley , ÁguaRESUMO
Human RNase MRP ribonucleoprotein complex is an essential endoribonuclease involved in the processing of ribosomal RNAs, mitochondrial RNAs and certain messenger RNAs. Its RNA subunit RMRP catalyzes the cleavage of substrate RNAs, and the protein components of RNase MRP are required for activity. RMRP mutations are associated with several types of inherited developmental disorders, but the pathogenic mechanism is largely unknown. Recent structural studies shed lights on the catalytic mechanism of yeast RNase MRP and the closely related RNase P; however, the structural and catalytic mechanism of RMRP in human RNase MRP complex remains unclear. Here we report the crystal structure of the P3 domain of RMRP in complex with the RPP20 and RPP25 proteins of human RNase MRP, which shows that the P3 RNA binds to a conserved positively-charged surface of the RPP20-RPP25 heterodimer through its distal stem and internal loop regions. The disease-related mutations of RMRPP3 are mostly located at the protein-RNA interface and are likely to weaken the binding of P3 to RPP20-RPP25. Moreover, the structure reveals a homodimeric organization of the entire RPP20-RPP25-RMRPP3 complex, which might mediate the dimerization of human RNase MRP complex in cells. These findings provide structural clues to the assembly and pathogenesis of human RNase MRP complex and also reveal a tetrameric feature of RPP20-RPP25 evolutionarily conserved with that of the archaeal Alba proteins.
Assuntos
Autoantígenos/química , RNA Longo não Codificante/química , Ribonuclease P/química , Proteínas Arqueais/química , Autoantígenos/metabolismo , Cristalografia por Raios X , Dimerização , Humanos , Modelos Moleculares , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Conformação de Ácido Nucleico , Conformação Proteica , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ribonuclease P/metabolismoRESUMO
BACKGROUND: We previously demonstrated that nasal administration of periodontitis gene vaccine (pVAX1-HA2-fimA) or pVAX1-HA2-fimA plus IL-15 as adjuvant provoked protective immunity in the periodontal tissue of SD rats. This study evaluated the immune effect of pVAX1-HA2-fimA plus CpG-ODN 1826 as an adjuvant in the SD rat periodontitis models to improve the efficacy of the previously used vaccine. METHODS: Periodontitis was induced in maxillary second molars in SD rats receiving a ligature and infected with Porphyromonas gingivalis. Forty-two SD rats were randomly assigned to six groups: A, control without P. gingivalis; B, P. gingivalis with saline; C, P. gingivalis with pVAX1; D, P. gingivalis with pVAX1-HA2-fimA; E, P. gingivalis with pVAX1-HA2-fimA/IL-15; F, P. gingivalis with pVAX1-HA2-fimA+CpG ODN 1826 (30 µg). The levels of FimA-specific and HA2-specific secretory IgA antibodies in the saliva of rats were measured by ELISA. The levels of COX-2 and RANKL were detected by immunohistochemical assay. Morphometric analysis was used to evaluate alveolar bone loss. Major organs were observed by HE staining. RESULTS: 30 µg could be the optimal immunization dose for CpG-ODN 1826 and the levels of SIgA antibody were consistently higher in the pVAX1-HA2-fimA+CpG-ODN 1826 (30 µg) group than in the other groups during weeks 1-8 (P < 0.05, except week 1 or 2). Morphometric analysis demonstrated that pVAX1-HA2-fimA+CpG-ODN 1826 (30 µg) significantly reduced alveolar bone loss in ligated maxillary molars in group F compared with groups B-E (P < 0.05). Immunohistochemical assays revealed that the levels of COX-2 and RANKL were significantly lower in group F compared with groups B-E (P < 0.05). HE staining results of the major organs indicated that pVAX1-HA2-fimA with or without CpG-ODN 1826 was not toxic for in vivo use. CONCLUSIONS: These results indicated that CpG-ODN 1826 (30 µg) could be used as an effective and safe mucosal adjuvant for pVAX1-HA2-fimA in SD rats since it could elicit mucosal SIgA responses and modulate COX-2 and RANKL production during weeks 1-8, thereby inhibiting inflammation and decreasing bone loss.
Assuntos
Periodontite , Vacinas , Animais , Imunização , Oligodesoxirribonucleotídeos , Periodontite/prevenção & controle , Porphyromonas gingivalis , Ratos , Ratos Sprague-DawleyRESUMO
Head and neck cancer (HNC) remains one of the most malignant tumors with a significantly high mortality. DNA methylation exerts a vital role in the prognosis of HNC. In this study, we try to screen abnormal differential methylation genes (DMGs) and pathways in Head-Neck Squamous Cell Carcinoma via integral bioinformatics analysis. Data of gene expression microarrays and gene methylation microarrays were obtained from the Cancer Genome Atlas database. Aberrant DMGs were identified by the R Limma package. We conducted the Cox regression analysis to select the prognostic aberrant DMGs and site-speciï¬c methylation. Five aberrant DMGs were recognized that significantly correlated with overall survival. The prognostic model was constructed based on five DMGs (PAX9, STK33, GPR150, INSM1, and EPHX3). The five DMG models acted as prognostic biomarkers for HNC. The area under the curve based on the five DMGs predicting 5-year survival is 0.665. Moreover, the correlation between the DMGs/site-speciï¬c methylation and gene expression was also explored. The findings demonstrated that the five DMGs can be used as independent prognostic biomarkers for predicting the prognosis of patients with HNC. Our study might lay the groundwork for further mechanism exploration in HNC and may help identify diagnostic biomarkers for early stage HNC.
Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA , Epigênese Genética , Epigenoma , Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Idoso , Epóxido Hidrolases/genética , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Fator de Transcrição PAX9/genética , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Receptores Acoplados a Proteínas G/genética , Proteínas Repressoras/genética , Fatores de Risco , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Fatores de TempoRESUMO
Chronic bacterial infections in the oral cavity influence the development of dental caries. Mutans streptococci are the major pathogenic cause of dental caries. The World Health Organization (WHO) ranks dental caries, cancer, and cardiovascular diseases as the three major global diseases that need urgent preventative and curative measures. However, substantial evidence suggests that traditional prevention and treatment strategies are inefficient in reducing the prevalence of dental caries. For protection against caries, it is important to develop effective vaccines that induce anticolonizing immunity against Streptococcus mutans infections. In the present investigation, we constructed a fusion anti-caries DNA vaccine (PAcA-ctxB) through fusing A region of cell surface protein PAc (PAcA) coding gene of mutans streptococci with cholera toxin B subunit coding gene (CTB). Afterward, the plasmids were integrated into tomato genomes through agrobacterium-mediated plant transformation technology. The presence of transgenes in the tomato genome was confirmed by PCR, ß-glucuronidase gene (GUS), and western blot. The expression of genes was confirmed at transcription and protein level. Altogether, the results presented herein showed that transgenic tomatoes may provide a useful system for the production of human caries antigen.
Assuntos
Proteínas de Bactérias/genética , Toxina da Cólera/genética , Cárie Dentária/prevenção & controle , Plantas Geneticamente Modificadas/genética , Solanum lycopersicum/genética , Streptococcus mutans/genética , Vacinas de DNA/genética , Cárie Dentária/imunologia , Vacinas de DNA/imunologiaRESUMO
A growing body of studies has demonstrated that long non-coding RNA (lncRNA) are regarded as the primary section of the ceRNA network. This is thought to be the case owing to its regulation of protein-coding gene expression by functioning as miRNA sponges. However, functional roles and regulatory mechanisms of lncRNA-mediated ceRNA in cervical squamous cell carcinoma (CESC), as well as their use for potential prediction of CESC prognosis, remains unknown. The aberrant expression profiles of mRNA, lncRNA, and miRNA of 306 cervical squamous cancer tissues and three adjacent cervical tissues were obtained from the TCGA database. A lncRNA-mRNA-miRNA ceRNA network in CESC was constructed. Meanwhile, Gene Ontology (GO) and KEGG pathway analysis were performed using Cytoscape plug-in BinGo and DAVID database. We identified a total of 493 lncRNA, 70 miRNA, and 1921 mRNA as differentially expressed profiles. An aberrant lncRNA-mRNA-miRNA ceRNA network was constructed in CESC, it was composed of 50 DElncRNA, 18 DEmiRNA, and 81 DEmRNA. According to the overall survival analysis, 3 out of 50 lncRNA, 10 out of 81 mRNA, and 1 out of 18 miRNA functioned as prognostic biomarkers for patients with CESC (P value < 0.05). We extracted the sub-network in the ceRNA network and found that two novel lncRNA were recognized as key genes. These included lncRNA MEG3 and lncRNA ADAMTS9-AS2. The present study provides a new insight into a better understanding of the lncRNA-related ceRNA network in CESC, and the novel recognized ceRNA network will help us to improve our understanding of lncRNA-mediated ceRNA regulatory mechanisms in the pathogenesis of CESC.
Assuntos
Biomarcadores Tumorais/biossíntese , Carcinoma de Células Escamosas/metabolismo , MicroRNAs/biossíntese , RNA Longo não Codificante/biossíntese , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Neoplasias do Colo do Útero/metabolismo , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA Neoplásico/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologiaRESUMO
BACKGROUND/AIMS: Kidney renal clear cell carcinoma (KIRC) is one of the most fatal malignancies due to late diagnosis and poor treatment. To improve its prognosis, a screening for molecular biomarkers of KIRC is urgently needed. Long non-coding RNAs (lncRNAs) play important roles in tumorigenesis and prognosis of cancers. However, it is not clear whether lncRNAs can be used as molecular biomarkers in predicting the survival of KIRC patients. METHODS: In this study, our aim was to identify lncRNAs/mRNAs signatures and their prognostic values in KIRC. The aberrant expression profile of mRNAs and lncRNAs in 529 KIRC tissues and 72 adjacent non-tumor pancreatic tissues were obtained from the Cancer Genome Atlas (TCGA). A weighted gene co-expression network analysis (WGCNA) of two key lncRNAs was constructed. We constructed an aberrant lncRNA-mRNA-miRNA ceRNA network in CESC. In addition, Gene Ontology (GO) and KEGG pathway analysis were performed. RESULTS: Using lncRNA/mRNA expression profiling data, the overall analysis revealed that two novel lncRNA signatures (DNM1P35 and MIR155HG) and several mRNAs were found to be significantly correlated with KIRC patient's overall analysis. Based on the target gene of the two lncRNA in co-expression network, the GO and KEGG analysis were also performed. A dysregulated lncRNA-related ceRNA network was also observed. CONCLUSION: These results suggested that the two novel lncRNAs signatures may act as independent prognostic biomarkers for predicting the survival of KIRC patient.
Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , RNA Longo não Codificante/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Bases de Dados Genéticas , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/genética , Neoplasias Renais/mortalidade , Masculino , Prognóstico , Modelos de Riscos Proporcionais , RNA Longo não Codificante/genética , RNA Mensageiro/metabolismoRESUMO
Pyoverdine I (PVDI) is a water-soluble fluorescein siderophore with strong iron chelating ability from the gram-negative pathogen Pseudomonas aeruginosa PAO1. Compared to common siderophores, PVDI is a relatively large compound whose synthesis requires a group of enzymes with different catalytic activities. In addition to four nonribosomal peptide synthetases (NRPS) which are responsible for the production of the peptide backbone of PVDI, several additional enzymes are associated with the modification of the side chains. PvdO is one of these enzymes and participates in PVDI precursor maturation in the periplasm. We determined the crystal structure of PvdO at 1.24 Å resolution. The PvdO structure shares a common fold with some FGly-generating enzymes (FGE) and is stabilized by Ca2+. However, the catalytic residues in FGE are not observed in PvdO, indicating PvdO adopts a unique catalytic mechanism.
Assuntos
Proteínas de Bactérias/química , Peptídeo Sintases/química , Pseudomonas aeruginosa/química , Cálcio/química , Varredura Diferencial de Calorimetria , Domínio Catalítico , Cristalografia por Raios X , Modelos Moleculares , Conformação ProteicaRESUMO
PURPOSE: To study the therapeutic effect of hemagglutinin-2 and fimbrial (HA2-FimA) vaccine on experimental periodontitis in rats. MATERIALS AND METHODS: The first batch of rats was divided into two groups and immunised with pure water or pVAX1-HA2-FimA at the age of 6, 7, and 9 weeks. After sacrificing the animals, total RNA was extracted from the spleens for RNA high-throughput sequencing (RNA-Seq) analysis. The second batch of rats was divided into four groups (A, B, C, D), and an experimental periodontitis rat model was established by suturing silk thread around the maxillary second molars of rats in groups B, C, and D for 4 weeks. The rats were immunised with pure water, pVAX1-HA2-FimA vaccine, empty pVAX1 vector, and pure water at 10, 11, and 13 weeks of age, respectively. Secretory immunoglobulin A (SIgA) antibodies and cathelicidin antimicrobial peptide (CAMP) levels in saliva were measured by enzyme-linked immunosorbent assay (ELISA). All rats were euthanised at 17 weeks of age, and alveolar bone loss was examined using micro-computed tomography (Micro-CT). RESULTS: Through sequencing analysis, six key genes, including Camp, were identified. Compared with the other three groups, the rats in the periodontitis+pVAX1-HA2-FimA vaccine group showed higher levels of SIgA and CAMP (p < 0.05). Micro-CT results showed significantly less alveolar bone loss in the periodontitis+pVAX1-HA2-FimA vaccine group compared to the periodontitis+pVAX1 group and periodontitis+pure water group (p < 0.05). CONCLUSION: HA2-FimA DNA vaccine can increase the levels of SIgA and CAMP in the saliva of experimental periodontitis model rats and reduce alveolar bone loss.
Assuntos
Periodontite , Vacinas de DNA , Animais , Periodontite/prevenção & controle , Periodontite/imunologia , Ratos , Modelos Animais de Doenças , Imunoglobulina A Secretora/análise , Proteínas de Fímbrias/imunologia , Perda do Osso Alveolar/prevenção & controle , Catelicidinas , Ratos Sprague-Dawley , Ensaio de Imunoadsorção Enzimática , Saliva/imunologia , Hemaglutininas/imunologia , Microtomografia por Raio-X , MasculinoRESUMO
OBJECTIVES: Calcifying nanoparticles (CNPs), referred to as nanobacteria (NB), are recognized to be associated with ectopic calcification. This study aims to isolate and culture CNPs from the dental plaque of patients with periodontal disease and investigate their possible role in unravelling the aetiology of periodontal disease. MATERIAL AND METHODS: Supragingival and subgingival plaques were sampled from 30 periodontitis patients for CNPs isolation and culture. Alkaline phosphatase (ALP) content changes were tracked over time. Positive samples underwent thorough morphological identification via hematoxylin and eosin (HE) staining, Alizarin red S (ARS), and transmission electron microscopy (TEM). The chemical composition of CNPs analysis involved calcium (Ca) and phosphorus (P) content determination, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). RESULTS: The subgingival plaque dental group exhibited a higher CNPs isolation rate at 36.67% (11/30) compared to the supragingival dental plaque group at 66.67% (20/30). ALP activity varied among the positive, negative and control groups. Morphological observation characterized the CNPs as round, oval, and ellipsoid particles with Ca deposits. Chemical analysis revealed the Ca/P ratio was 0.6753. Hydroxyl, methyl, carbonate, phosphate, hydrogen phosphate, and dihydrogen phosphate were detected by FTIR; the main chemical components detected by XRD were hydroxyapatite and tricalcium phosphate. CONCLUSION: CNPs were found in periodontitis-related dental plaque and exhibited the potential to develop calcified structures resembling dental calculus. However, the potential involvement of ALP in CNPs formation requires deeper exploration, as does the precise nature of its role and the interrelation with periodontitis demand a further comprehensive investigation.
Assuntos
Fosfatase Alcalina , Nanopartículas Calcificantes , Placa Dentária , Difração de Raios X , Humanos , Nanopartículas Calcificantes/metabolismo , Placa Dentária/microbiologia , Placa Dentária/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Fosfatase Alcalina/metabolismo , Fósforo/análise , Fósforo/metabolismo , Periodontite/microbiologia , Periodontite/patologia , Microscopia Eletrônica de Transmissão , Feminino , Adulto , Cálcio/metabolismo , Cálcio/análise , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: The removal of impacted third molars by surgery may occur with a series of complications, whereas limited information about the postoperative pathogenesis is available. The objective of this study is to identify changes in gene expression after flap surgical removal of impacted third molars and provide potential information to reduce postoperative complications. METHODS: The gingival tissues of twenty patients with flap surgical removal of impacted third molars and twenty healthy volunteers were collected for gene expression testing. The collected gingival tissues were used RNA sequencing technology and quantitative real-time PCR validation was performed. DEG was mapped to protein databases such as GO and KEGG for functional annotation and, based on annotation information, for mining of differential expression genes in patients with mpacted third molars. RESULTS: A total of 555 genes were differentially expressed. Among the top up-regulated genes, HLA-DRB4, CCL20, and CXCL8 were strongly associated with immune response and signal transduction. Among the top down-regulated genes, SPRR2B, CLDN17, LCE3D and LCE3E were related to keratinocyte differentiation, IFITM5, and BGLAP were related to bone mineralization, UGT2B17 is associated with susceptibility to osteoporosis. KEGG results showed that the DEGs were related to multiple disease-related pathways. CONCLUSION: This first transcriptome analysis of gingival tissues from patients with surgical removal of impacted third molars provides new insights into postoperative genetic changes. The results may establish a basis for future research on minimizing the incidence of complications after flap-treated third molars.
RESUMO
BACKGROUND: Portal shunt and immune status related to the spleen are related to the occurrence of hepatic encephalopathy (HE). It is unknown whether spleen volume before transjugular intrahepatic portosystemic shunt (TIPS) is related to postoperative HE. AIM: To investigate the relationship between spleen volume and the occurrence of HE. METHODS: This study included 135 patients with liver cirrhosis who underwent TIPS, and liver and spleen volumes were elevated upon computed tomography imaging. The Kaplan-Meier curve was used to compare the difference in the incidence rate of HE among patients with different spleen volumes. Univariate and multivariate Cox regression analyses were performed to identify the factors affecting overt HE (OHE). Restricted cubic spline was used to examine the shapes of the dose-response association between spleen volumes and OHE risk. RESULTS: The results showed that 37 (27.2%) of 135 patients experienced OHE during a 1-year follow-up period. Compared with preoperative spleen volume (901.30 ± 471.90 cm3), there was a significant decrease in spleen volume after TIPS (697.60 ± 281.0 cm3) in OHE patients. As the severity of OHE increased, the spleen volume significantly decreased (P < 0.05). Compared with patients with a spleen volume ≥ 782.4 cm3, those with a spleen volume < 782.4 cm3 had a higher incidence of HE (P < 0.05). Cox regression analysis showed that spleen volume was an independent risk factor for post-TIPS OHE (hazard ratio = 0.494, P < 0.05). Restricted cubic spline model showed that with an increasing spleen volume, OHE risk showed an initial increase and then decrease (P < 0.05). CONCLUSION: Spleen volume is related to the occurrence of OHE after TIPS. Preoperative spleen volume is an independent risk factor for post-TIPS OHE.
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Prostate cancer (PCa) is one of the most fundamental causes of cancerrelated mortality and morbidity among males. However, the underlying mechanisms have not yet been fully clarified. The present study aimed to investigate the effects of plasmacytoma variant translocation 1 (PVT1) on the malignant behaviors of PCa cells and to explore the possible molecular mechanisms involved. The expression levels of PVT1 and microRNA (miRNA/miR)27b3p in PCa tissues and cell lines were measured using reversetranscritpionquantitative polymerase chain reaction. Methyltransferase 3 (METTL3)mediated PVT1 N6methyladenosine (m6A) modifications were detected using RNA immunoprecipitation (RIP) and RNA pulldown assays. Bioinformatics analysis was used to predict the interactions of miR27b3p with PVT1 and bloom syndrome protein (BLM), and these interactions were validated using RIP, dualluciferase reporter and biotin pulldown assays. The functional importance of miR27b3p, PVT1 and BLM within PCa cells was assessed through the in vitro utilization of Cell Counting Kit8, Transwell, wound healing and colony formation assays, and the in vivo use of a mouse xenograft model. The results revealed the high expression level of PVT1 in PCa tissues and cells, and epigenetic analyses revealed the upregulation of PVT1 expression following METTL3mediated m6A modification. PVT1 overexpression induced PCa cells to become more proliferative, migratory and invasive, whereas PVT1 knockdown led to the opposite phenotype. Furthermore, miR27b3p was found to target both PVT1 and BLM, and PVT1 functioned to sequester miR27b3p within cells, thereby indirectly promoting the BLM expression level. BLM overexpression reversed the adverse effects of PVT1 knockdown on the migratory, proliferative and invasive capabilities of PCa cells in vitro and in vivo. The overexpression of PVT1 contributed to the aggressive phenotype of PCa cells by regulating the miR27b3p/BLM axis. On the whole, the findings of the present study may provide novel potential targets for the treatment of PCa.
Assuntos
MicroRNAs , Neoplasias da Próstata , RNA Longo não Codificante , Humanos , Camundongos , Animais , Masculino , RNA Longo não Codificante/genética , Neoplasias da Próstata/genética , MicroRNAs/genética , MetiltransferasesRESUMO
Monascus pigments (MPs) were adsorbed using calcium carbonate to produce CaCO3-MPs lakes. The fundamental properties and formation mechanism of the lakes were investigated. Results indicated that CaCO3 displayed a high enough affinity for the MPs to form colorant lakes, while the MPs tended to transform the CaCO3 crystals from calcite to vaterite. The adsorption of MPs by CaCO3 followed the Freundlich isothermal model with n value higher than 1, confirming it as physical adsorption. The ΔG0 (-29 to â¼-33 kJ/mol) and ΔH0(30-55 kJ/mol) indicated that lake formation was a spontaneous and endothermic process. UV/Vis spectroscopic analysis verified the complex formation between Ca2+ and MPs via physical bonding, suggesting a possible attraction between the Ca2+ and glutamate residues of the MPs. EDS showed that the MPs were trapped inside the particles. FTIR spectroscopy and XPS further confirmed that the physical bonding was the primary driving force behind the lake formation.