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Mechanistic understanding of acetoclastic methanogenesis is pivotal for optimizing anaerobic digestion for efficient methane production. In this study, two different operational modes, continuous flow reactor (CFR) and sequencing batch reactor (SBR), accompanied with solids retention times (SRT) of 10 days (SBR10d and CFR10d) and 25 days (SBR25d and CFR25d) were implemented to elucidate their impacts on microbial communities and energy metabolism of methanogens in acetate-fed systems. Microbial community analysis revealed that the relative abundance of Methanosarcina (16.0%-46.0%) surpassed Methanothrix (3.7%-22.9%) in each reactor. SBRs had the potential to enrich both Methanothrix and Methanosarcina. Compared to SBRs, CFRs had lower total relative abundance of methanogens. Methanosarcina exhibited a superior enrichment in reactors with 10-day SRT, while Methanothrix preferred to be acclimated in reactors with 25-day SRT. The operational mode and SRT were also observed to affect the distribution of acetate-utilizing bacteria, including Pseudomonas, Desulfocurvus, Mesotoga, and Thauera. Regarding enzymes involved in energy metabolism, Ech and Vho/Vht demonstrated higher relative abundances at 10-day SRT compared to 25-day SRT, whereas Fpo and MtrA-H showed higher relative abundances in SBRs than those in CFRs. The relative abundance of genes encoding ATPase harbored by Methanothrix was higher than Methanosarcina at 25-day SRT. Additionally, the relative abundance of V/A-type ATPase (typically for methanogens) was observed higher in SBRs compared to CFRs, while the F-type ATPase (typically for bacteria) exhibited higher relative abundance in CFRs than that in SBRs.
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Reatores Biológicos , Metabolismo Energético , Metano , Reatores Biológicos/microbiologia , Metano/metabolismo , Acetatos/metabolismo , Methanosarcina/metabolismo , Methanosarcina/genética , Anaerobiose , AclimataçãoRESUMO
INTRODUCTION: Adenoidectomy is a common procedure in children who have adenoid hypertrophy (AH), but anesthesia risks should be considered. We proposed a novel classification system for adenoids based on their appearance. Additionally, we explored whether the novel classification of adenoids correlates with the response to therapy and thus might be helpful for further treatment recommendations. METHODS: We used fiberoptic nasal endoscopy to determine the degree and appearance of AH. Obstructive Sleep Apnea Questionnaire (OSA-18) was used to assess the quality of life of children with AH. The adenoids were divided into three types: edematous type, common type, and fibrous type. In adenoid tissues, the eosinophils were counted. Immunohistochemistry and Western blot were done to determine the expression of CysLTR1, CysLTR2, CGR-α, and CGR-ß in different types of adenoids. RESULTS: 70.67% (106/150) of AH patients presented with allergic rhinitis (AR), and of them, 68% (72/106) of adenoids were the edematous type. The expressions of CGR-α, CGR-ß, and eosinophil count were higher in the edematous compared with the common and fibrous types. The expression of the leukotriene receptor was similar in all types. Upon montelukast combined with nasal glucocorticoid therapy, improvement of OSA-18 scores and AH grade was significantly compared to montelukast monotherapy for edematous type. There was not any statistically significant difference between the scores upon montelukast combined with nasal glucocorticoid and montelukast monotherapy for common and fibrous type. We observed a positive correlation between eosinophil count in the blood and in the adenoid tissue. CONCLUSION: AR was the risk factor for the development of edematous AH. All subtypes of AH responded to montelukast, while there was an additional effect of nasal glucocorticoid in the edematous type. A combination therapy of nasal glucocorticoid with leukotriene receptor antagonist can be recommended for AH patients with AR, patients with edematous adenoids, and/or patients with increased eosinophils in blood routine.
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Tonsila Faríngea , Rinite Alérgica , Apneia Obstrutiva do Sono , Criança , Humanos , Tonsila Faríngea/metabolismo , Glucocorticoides , Qualidade de Vida , Rinite Alérgica/diagnóstico , Rinite Alérgica/tratamento farmacológico , Rinite Alérgica/metabolismo , Apneia Obstrutiva do Sono/metabolismoRESUMO
The functional mechanism of microbial assembly of activated sludge (AS) in urban wastewater treatment plants (UWTPs) remains unclear. A comprehensive quantitative evaluation of the contribution of influent immigration and environmental factors to AS community composition requires investigation. In this study, the microbial characteristics of six full-scale UWTPs with different influent compositions and environmental factors (altitude, temperature, dissolved oxygen (DO), pH, chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH4+-N), and total phosphorus (TP)) were analyzed to determine the main forces affecting the bacterial assembly of AS microbial communities. Abundant and core taxa were screened out based on the abundance and frequency of operational taxonomic units (OTUs) occurrence in all samples. Abundant OTUs (18.7% occurrence) accounted for 87.7% of the total 16S rRNA sequences, while rare OTUs (71.7% occurrence) accounted for only 7.8% of the total 16S rRNA sequences. A total of 135 OTUs were identified as core taxa, accounting for 14.6-26.2% of the total reads, of which 83 OTUs belonged to abundant taxa. The richness and uniformity of the influent community were significantly lower than those of the AS system. The community composition in influent varied from that in AS. Moreover, about 89.7% (86.5% of 16S rRNA sequences) OTUs in AS samples showed positive growth rates, indicating that immigration of influent communities had a limited effect on the microbial composition of AS. Redundancy analysis (RDA) combined with co-occurrence network showed that the bacterial assembly of microbial communities was significantly correlated with altitude, pH, and TN (P < 0.05), and these three parameters could explain 23.3%, 21.1%, and 17.7% of the bacterial assembly of AS microbial communities in UWTPs, respectively.
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Microbiota , Esgotos , Emigração e Imigração , RNA Ribossômico 16S/genética , Esgotos/química , Águas Residuárias/microbiologiaRESUMO
BACKGROUND: At present, there is a new variant Omicron BA.2 of SARS-CoV-2. In some previous studies, it was found that CBC, NLR, CRP, SAA, etc. in patients with SARS-CoV-2 had a series of changes, which were significantly correlated with the diagnosis and prognosis of patients. Therefore, in order to find specific diagnostic indicators, we explore the changes in these blood indicators and inflammatory indicators in patients with the SARS-CoV-2 Omicron. METHODS: A total of 127 Omicron confirmed patients who had visited fever clinic was selected as the positive group, and 75 Omicron excluded patients were selected as the negative group. We collected and analyzed the CBC, CRP, SAA test data, and clinical data of all subjects for analysis and statistics. RESULTS: WBC, NEU, LYM, EOS, PLT, PCT, LYM * NEU count compared with the negative group were significantly lower (p < 0.05); on the contrary, CNR were significantly higher (p < 0.05); The levels of CRP and SAA were not significantly different from those of the negative group (p > 0.05); the AUC of 0.781 for the diagnosis of LYM * NEU with an optimal cutoff value of 5.79, with a sensitivity and specificity of 68% and 73%, respectively, Youden index of 0.41, giving the best diagnostic performance. CONCLUSION: The decreased LYM * NEU count can be used as the early, rapid, and accurate diagnostic indicator for Omicron. While due to the attenuated toxicity of BA.2 sublineage, CRP and SAA had no significance in the differential diagnosis of confirmed patients.
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COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , China/epidemiologia , Humanos , Contagem de Linfócitos , Linfócitos , Neutrófilos , Curva ROC , Estudos RetrospectivosRESUMO
Enhancer of Zeste Homolog 2(EZH2), which can change chromatin structure by tri-methylation of the 27th lysine of H3 in nucleosome histone (H3K27me3), is involved in different types of cancers. However, the role and mechanism underlying aberrant EZH2 expression in laryngeal squamous cells carcinoma (LSCC) remain unclear. In the present study, we found that down-regulation of EZH2 and H3K27me3 in LSCC cells (Hep-2 and SCC10A) resulted in an mesenchymal-epithelial transition(MET) like cell morphology and lower invasion in vitro, weakened tumor growth, intrahepatic and pulmonary metastasis in vivo. Furthermore, EZH2 promoted the epithelial-mesenchymal transition(EMT) process through down-regulation of Ca2+ dependent cell adhesion molecule E (E-cadherin) and up-regulation of H3K27me3 in vitro and in vivo. Moreover, E-cadherin was transcriptionally induced upon stable knockdown of EZH2, and quantitative chromatin immunoprecipitation(qChIP) analysis confirmed the depletion of H3K27me3 enrichment on E-cadherin promoter upon EZH2 knockdown in Hep-2 and SCC10A cells. In addition, the expression of EZH2 was positively correlated with that of H3K27me3 and both of them were inversely correlated with E-cadherin expression in human LSCC tissues. In summary, this study indicated that EZH2 promoted invasion and metastasis of LSCC via EMT through H3K27me3.
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Carcinoma de Células Escamosas/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Neoplasias Laríngeas/metabolismo , Animais , Antígenos CD , Caderinas/metabolismo , Cálcio/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Metástase Linfática , Camundongos , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo RealRESUMO
BACKGROUND: Silence of the tumor suppressor miR-34c is implicated in the development of colorectal cancer (CRC). For the past few years, Resveratrol (Res) has been introduced to oncotherapies alone or with traditional chemotherapeutic drugs. However, the study of molecular mechanism involved in the anti-CRC effect of Res is still ongoing. METHODS: The anti-CRC effect of Res alone or with Oxaliplatin (Oxa) was determined by cell viability assay, soft agar colony formation assay, flow cytometry and real-time cellular analyzer in HT-29 (p53+) and HCT-116 (p53-) CRC cell lines. Expressions of miR-34c and its targets were detected by qPCR and/or western blot. To evaluate the role of miR-34c in anti-CRC effect by Res alone or with Oxa, miR-34c was up or down-regulated by lentiviral mediation or specific inhibitor, respectively. To investigate how miR-34c was increased by Res, the methylation status of miR-34c promoter was detected by MSP. The tumor bearing mouse model was established by subcutaneous injection of HCT-116 cells to assess anti-CRC effect of Res alone or with Oxa in vivo. IL-6 and TNF-α in xenografts were detected by ELISA. RESULTS: Res inhibited cell viability, proliferation, migration and invasion as well as promoted apoptosis both in HT-29 and HCT-116 CRC cells. The anti-CRC effect of Res was partially but specifically through up-regulating miR-34c which further knocked down its target KITLG; and the effect was enhanced in the presence of p53 probably through inactivating PI3K/Akt pathway. Besides, Res sensitized CRC cells to Oxa in a miR-34c dependent manner. The xenograft experiments showed that exposure to Res or Oxa suppressed tumor growth; and the efficacy was evidently augmented by the co-treatment of Res and Oxa. Likewise, miR-34c level was elevated in xenografts of Res-treated mice while the KITLG was decreased. Finally, Res clearly reduced IL-6 in xenografts. CONCLUSION: Res suppressed CRC by specifically activating miR-34c-KITLG in vitro and in vivo; and the effect was strengthened in the presence of p53. Besides, Res exerted a synergistic effect with Oxa in a miR-34c dependent manner. We also suggested that Res-increased miR-34c could interfere IL-6-triggered CRC progression.
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Antineoplásicos/farmacologia , Neoplasias Colorretais/genética , MicroRNAs/metabolismo , Estilbenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/efeitos dos fármacos , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Reação em Cadeia da Polimerase em Tempo Real , Resveratrol , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
This study comprehensively deciphered the effect of silver nanoparticles (AgNPs) on anammox flocculent sludge, including nitrogen removal performance, microbial community structure, functional enzyme abundance, antibiotic resistance gene (ARGs) dissemination, and horizontal gene transfer (HGT) mechanisms. After long-term exposure to 0-2.5 mg/L AgNPs for 200 cycles, anammox performance significantly decreased (P < 0.05), while the relative abundances of dominant Ca. Kuenenia and anammox-related enzymes (hzsA, nirK) increased compared to the control (P < 0.05). For antibiotic resistome, ARG abundance hardly changed with 0-0.5 mg/L AgNPs but decreased by approximately 90% with 1.5-2.5 mg/L AgNPs. More importantly, AgNPs effectively inhibited MGE-mediated HGT of ARGs. Additionally, structural equation model (SEM) disclosed the underlying relationship between AgNPs, the antibiotic resistome, and the microbial community. Overall, AgNPs suppressed the anammox-driven nitrogen cycle, regulated the microbial community, and prevented the spread of ARGs in anammox flocs. This study provides a theoretical baseline for an advanced understanding of the ecological roles of nanoparticles and resistance elements in engineered ecosystems.
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Resistência Microbiana a Medicamentos , Nanopartículas Metálicas , Prata , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Resistência Microbiana a Medicamentos/genética , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Transferência Genética Horizontal , Esgotos/microbiologia , Nitrogênio/química , Nitrogênio/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Anaerobiose , Microbiota/efeitos dos fármacos , OxirreduçãoRESUMO
Introduction: The proper operation of wastewater treatment plants is a key factor in maintaining a stable river and lake environment. Low purification efficiency in winter is a common problem in high-altitude wastewater treatment plants (WWTPs), and analysis of the microbial community involved in the sewage treatment process at high-altitude can provide valuable references for improving this problem. Methods: In this study, the bacterial communities of high- and low-altitude WWTPs were investigated using Illumina high-throughput sequencing (HTS). The interaction between microbial community and environmental variables were explored by co-occurrence correlation network. Results: At genus level, Thauera (5.2%), unclassified_Rhodocyclaceae (3.0%), Dokdonella (2.5%), and Ferribacterium (2.5%) were the dominant genera in high-altitude group. The abundance of nitrogen and phosphorus removal bacteria were higher in high-altitude group (10.2% and 1.3%, respectively) than in low-altitude group (5.4% and 0.6%, respectively). Redundancy analysis (RDA) and co-occurrence network analysis showed that altitude, ultraviolet index (UVI), pH, dissolved oxygen (DO) and total nitrogen (TN) were the dominated environmental factors (p < 0.05) affecting microbial community assembly, and these five variables explained 21.4%, 20.3%, 16.9%, 11.5%, and 8.2% of the bacterial assembly of AS communities. Discussion: The community diversity of high-altitude group was lower than that of low-altitude group, and WWTPs of high-altitude aeras had a unique microbial community structure. Low temperature and strong UVI are pivotal factors contributing to the reduced diversity of activated sludge microbial communities at high-altitudes.
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Here we report a copper-catalyzed protocol for the synthesis of α-chloroketones from aromatic alkenes including electron-deficient olefins under visible-light irradiation. Preliminary mechanistic studies show that the peroxo Cu(II) species is the key intermediate and hydroperoxyl (HOOâ ) and chlorine (Clâ ) radicals can be generated by ligand-to-metal charge transfer (LMCT).
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Alcenos , Luz , Cobre , CatáliseRESUMO
The current ecosystem services of karst protected areas cannot fully enhance human well-being, and the value of eco-products cannot be effectively realized. Research on eco-products and ecological civilization is conducive to the regional sustainability. The results of a statistical analysis of 258 related articles indicate: (1) the number of published articles has increased rapidly after slow growth, indicating that this research field has become a research hotspot and has broad research prospects; (2) the research content mainly involves five aspects, such as eco-product supply, eco-product value realization, eco-industry, ecological civilization, and monitoring and evaluation; (3) the articles research area is mainly distributed in the karst areas with a fragile ecological environment in China and the eco-product value realization and ecological civilization pilot areas; (4) the research frontiers are revealed from four aspects of eco-product supply ability, eco-product value realization, the driving force of eco-product value realization on the formation of eco-industry, model and effectiveness of ecological civilization; (5) it is necessary to deepen the research on the improvement mechanism of eco-product supply capacity, the classification systems and value accounting standards of eco-products, the formation mechanism of eco-industries under ecological threshold constraints and the driving mechanism of eco-industry to ecological civilization.
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Ecologia , Ecossistema , Civilização , Conservação dos Recursos Naturais/métodos , Ecologia/métodos , Humanos , IndústriasRESUMO
Ovarian cancer is the most fatal gynecological cancer worldwide, yet the fundamental mechanism of malignancy acquisition in ovarian cancer remains unknown. miRNA has been implicated to a variety of diseases, including cancer initiation and progression. Cyclin-D2 (CCND2) is ubiquitously implicated in cancer uncontrol cell proliferation. Bioinformatic research revealed that CCND2 is a candidate gene for miR-93-5p with a binding site in its 3'UTR region in the current study. Using our ovarian cancer sample, we verified that miR-93-5p is negatively correlated with CCND2 mRNA and protein levels. Luciferase report assay revealed miR-93-5p inhibits CCND2 production through binding to the 3'UTR region. The expression of miR-93-5p in ovarian cancer patient samples was then determined, and a survival analysis was performed. Our findings showed that miR-93-5p is downregulated in ovarian cancer and is a favorable predictive factor in ovarian cancer patient. CCK8 assay, wound healing assay and flow cytometry-based cell cycle and apoptotic cell analyses were employed here. We found that miR-93-5p suppresses ovarian cancer cell proliferation and migration while enhances cell death. Our research certified that miR-93-5p reduces ovarian cancer malignancy by targeting CCND2.
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OBJECTIVE: To investigate the effect and prognosis of subtotal intracapsular tonsillectomy. METHODS: All children (n=162) with tonsillar hypertrophy and chronic tonsillitis were randomly divided into two groups: tonsillectomy (n=75) and subtotal intracapsular tonsillectomy (n=87). Tonsillectomy: the tonsillar tissue was completely removed along with the tonsillar capsule. Subtotal intracapsular tonsillectomy: 80% to 90% of the tonsils and the complete epithelium of the tonsillar crypts were removed without damaging the tonsillar capsule. The Face, Legs, Activity, Cry, and Consolability (FLACC) and parents' postoperative pain measure (PPPM) scales were used to evaluate postoperative pain, and the obstructive sleep apnea (OSA)-18 questionnaire was used to assess the children's postoperative quality of life. The patients were followed-up for 2 years. RESULTS: 1. The FLACC and PPPM scales indicated that the children's postoperative pain after subtotal intracapsular tonsillectomy was significantly less than that of children undergoing tonsillectomy. 2. The OSA-18 scale scores indicated that subtotal intracapsular tonsillectomy significantly improved the children's quality of life. 3. Two years after subtotal intracapsular tonsillectomy, no patients required reoperation. CONCLUSION: Subtotal intracapsular tonsillectomy may be the first choice for tonsillar hypertrophy and chronic tonsillitis patients.
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Apneia Obstrutiva do Sono , Tonsilectomia , Tonsilite , Criança , Humanos , Dor Pós-Operatória , Tonsila Palatina/cirurgia , Qualidade de Vida , Apneia Obstrutiva do Sono/cirurgia , Tonsilite/cirurgiaRESUMO
Epilepsy is a chronic neurological disease which is usually associated with psychiatric comorbidities. Depsression and cognition impairment are considered to be the most common psychiatric comorbidities in epilepsy patients. However, the specific contribution of epilepsy made to these psychiatric comorbidities remains largely unknown. Here we use pentylenetetrazole (PTZ) kindling, a chronic epilepsy model, to identify neuronal nitric oxide synthase (nNOS) as a signaling molecule triggering PTZ kindling-induced cognitive impairment and depressive-like behavior. Furthermore, we identified that both hippocampal MAPK and PI3K/AKT signaling pathways were activated in response to PTZ kindling, and the increased MAPK and PI3K/AKT signaling activation was paralleled by increased level of reactive oxygen species (ROS) in the hippocampus. However, the PTZ kindling-induced MAPK, PI3K/AKT signaling activities and the ROS level were attenuated by nNOS gene deficiency, suggesting that nNOS may act through ROS-mediated MAPK and PI3K/AKT signaling pathways to trigger cognition deficit and depressive-like behavior in PTZ-kindled mice. Our findings thus define a specific mechanism for chronic epilepsy-induced cognitive impairment and depressive-like behavior, and identify a potential therapeutic target for psychiatric comorbidities in chronic epilepsy patients.
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Epilepsy is one of the most common chronic neurological disorders which provoke progressive neuronal degeneration. Endoplasmic reticulum (ER) stress has recently been recognized as pivotal etiological factors contributing to epilepsy-induced neuronal damage. However, the specific contribution of epilepsy made to ER stress remains largely elusive. Here we use pentylenetetrazole (PTZ) kindling, a chronic epilepsy model, to identify neuronal nitric oxide synthase (nNOS) as a signaling molecule triggering PTZ kindling epilepsy-induced ER stress and oxidative damage. By genetic deletion of nNOS gene, we further demonstrated that nNOS acts through peroxynitrite, an important member of reactive nitrogen species, to trigger hippocampal ER stress and oxidative damage in the PTZ-kindled mice. Our findings thus define a specific mechanism for chronic epilepsy-induced ER stress and oxidative damage, and identify a potential therapeutic target for neuroprotection in chronic epilepsy patients.
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Glycogen synthase kinase-3ß (GSK-3ß) and protein phosphatase 2A (PP2A) are the important enzymes controlling tau hyperphosphorylation. The relationship between these two enzymes and its impact on tau hyperphosphorylation are not well understood. In the present study, we determined the cross talk between PI3K-AKT-GSK-3ß and PP2A pathways and found that the former regulated the methylation of PP2Ac via GSK-3ß. Upregulation of GSK-3ß led to an increase in the methylation and activity of PP2Ac through suppression of protein phosphatase methylesterase-1 expression and phosphorylation of leucine carboxyl methyltransferase 1. PP2A also regulated GSK-3ß phosphorylation. Downregulation of PP2A enhanced Ser9 phosphorylation of GSK-3ß and inhibited its kinase activity. Thus, GSK-3ß and PP2A regulate each other and control tau phosphorylation both directly and indirectly through each other. Reduction of tau phosphorylation by inhibition of GSK-3ß may be more than offset by inhibition of PP2A through a shift in phosphatase methylesterase-1/leucine carboxyl methyltransferase 1 balance; PP2A regulates phosphorylation of tau at Ser262/356, a required site for tau pathology. These findings suggest targeting PP2A rather than GSK-3ß to inhibit tau pathology.
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Quinase 3 da Glicogênio Sintase/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteína Fosfatase 2/fisiologia , Transdução de Sinais/fisiologia , Proteínas tau/metabolismo , Animais , Encéfalo/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células HEK293 , Células HeLa , Humanos , Metilação , Camundongos Endogâmicos C57BL , Fosforilação/genética , Proteína O-Metiltransferase/metabolismo , Transdução de Sinais/genéticaRESUMO
Triptolide, an active compound extracted from Chinese herb Leigongteng (Tripterygium wilfordii Hook F.), shows a broad-spectrum of anticancer activity through its cytotoxicity. However, the efficacy of triptolide on laryngocarcinoma rarely been evaluated, and the mechanism by which triptolide-induced cellular apoptosis is still not well understood. In this study, we found that triptolide significantly inhibited the laryngocarcinoma HEp-2 cells proliferation, migration and survivability. Triptolide induces HEp-2 cell cycle arrest at the G1 phase and apoptosis through intrinsic and extrinsic pathways since both caspase-8 and -9 are activated. Moreover, triptolide enhances p53 expression by increasing its stability via down-regulation of E6 and E6AP. Increased p53 transactivates down-stream target genes to initiate apoptosis. In addition, we found that short time treatment with triptolide induced DNA damage, which was consistent with the increase in p53. Furthermore, the cytotoxicity of triptolide is decreased by p53 knockdown or use of caspases inhibitor. In conclusion, our results demonstrated that triptolide inhibits cell proliferation and induces apoptosis in laryngocarcinoma cells by enhancing p53 expression and activating p53 functions through induction of DNA damage and suppression of E6 mediated p53 degradation. These studies indicate that triptolide is a potential anti-laryngocarcinoma drug.