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1.
Materials (Basel) ; 17(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612017

RESUMO

The microbial hybrid system modified by magnetic nanomaterials can enhance the interfacial electron transfer and energy conversion under the stimulation of a magnetic field. However, the bioelectrocatalytic performance of a hybrid system still needs to be improved, and the mechanism of magnetic field-induced bioelectrocatalytic enhancements is still unclear. In this work, γ-Fe2O3 magnetic nanoparticles were coated on a Shewanella putrefaciens CN32 cell surface and followed by placing in an electromagnetic field. The results showed that the electromagnetic field can greatly boost the extracellular electron transfer, and the oxidation peak current of CN32@γ-Fe2O3 increased to 2.24 times under an electromagnetic field. The enhancement mechanism is mainly due to the fact that the surface modified microorganism provides an elevated contact area for the high microbial catalytic activity of the outer cell membrane's cytochrome, while the magnetic nanoparticles provide a networked interface between the cytoplasm and the outer membrane for boosting the fast multidimensional electron transport path in the magnetic field. This work sheds fresh scientific light on the rational design of magnetic-field-coupled electroactive microorganisms and the fundamentals of an optimal interfacial structure for a fast electron transfer process toward an efficient bioenergy conversion.

2.
Bioelectrochemistry ; 158: 108712, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38636365

RESUMO

The main challenges (sluggish electron transfer, low energy density) hinder the future application of enzymatic biofuel cells (EBFCs), which urgent to take effective measures to solve these issues. In this work, a composite of Au nanoparticles decorated graphdiyne (AuNPs@GDY) is fabricated and employed as the carrier of enzyme (G6PDH), and a mechanism based on π-π interaction of electron transfer is proposed to understand bioelectrocatalysis processes. The results show that the AuNPs@GDY composite exhibits the highest current density among the three materials (GDY, AuNPs, and AuNPs@GDY), which is 3.4 times higher than that of GDY and 2.5 times higher than that of AuNPs. Furthermore, the results reveal that the AuNPs could increase the loading of enzymes and provide more active site for reaction, while GDY provides highly π-conjugated structure and unique sp/sp2-hybridized linkages interface. This work provides new insights to explore a theoretical basis for the development of more efficient bioelectrocatalytic systems.

3.
Lasers Med Sci ; 38(1): 188, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596454

RESUMO

Metastatic prostate cancer (mPCa) patients complicated with bladder outlet obstruction (BOO) are often referred to a urologist. Androgen deprivation therapy (ADT) combined with indwelling catheter usually be the initial management. To retrospectively analysis the safety and efficacy of simultaneous thulium laser resection of the prostate (TmLRP) and transperineal prostate biopsy in metastatic prostate cancer with bladder outlet obstruction. From January 2016 to December 2021, 67 clinically diagnosed mPCa with BOO patients were included in this study. All patients were preoperatively assessed with international prostate symptom score (IPSS), QoL, serum prostate-specific antigen (PSA), prostate volume evaluation by transrectal ultrasound, postvoid residual urine volume (PVR), and maximum flow rate (Qmax). Preoperative and perioperative parameters at 1-, 3-, and 6-month follow-up were also evaluated. All complications were recorded. Simultaneous TmLRP and transperineal prostate biopsy had obvious advantages for clinically diagnosed mPCa patients with BOO, including short overall operation time (52 ± 23.3 min), little hemoglobin decrease (0.6 ± 0.7 g/l), and short hospital stay (average 3.8 days). In addition, simultaneous TmLRP and transperineal prostate biopsy also brought them significant improvement on IPSS, QoL score, Qmax, and PVR volume (P < 0.001) at 1-, 3-, and 6-month follow-up after operation compared to preoperative parameters. Complications were in a low incidence. Simultaneous TmLRP and transperineal prostate biopsy is a bloodless operation with immediate effect and little perioperative complication. Importantly, it is a promising technology in the diagnosis and treatment of clinically diagnosed mPCa patients with BOO.


Assuntos
Neoplasias da Próstata , Obstrução do Colo da Bexiga Urinária , Masculino , Humanos , Próstata/cirurgia , Neoplasias da Próstata/complicações , Neoplasias da Próstata/cirurgia , Túlio , Antagonistas de Androgênios , Qualidade de Vida , Estudos Retrospectivos , Obstrução do Colo da Bexiga Urinária/diagnóstico , Obstrução do Colo da Bexiga Urinária/etiologia , Obstrução do Colo da Bexiga Urinária/cirurgia , Biópsia , Lasers
4.
Int J Biol Sci ; 19(11): 3441-3455, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497009

RESUMO

Benign prostatic hyperplasia (BPH) is a condition that becomes more common with age and manifests itself primarily as the expansion of the prostate and surrounding tissues. However, to date, the etiology of BPH remains unclear. In this respect, we performed single-cell RNA sequencing of prostate transition zone tissues from elderly individuals with different prostate volumes to reveal their distinct tissue microenvironment. Ultimately, we demonstrated that a reduced Treg/CD4+ T-cell ratio in the large-volume prostate and a relatively activated immune microenvironment were present, characterized partially by increased expression levels of granzymes, which may promote vascular growth and profibrotic processes and further exacerbate BPH progression. Consistently, we observed that the prostate gland of patients taking immunosuppressive drugs usually remained at a smaller volume. Furthermore, in mouse models, we confirmed that both suppression of the immune system with rapamycin and induction of Treg proliferation with low doses of IL-2 therapy indeed prevented the progression of BPH. Taken together, our findings suggest that an activated immune microenvironment is necessary for prostate volume growth and that Tregs can reverse this immune activation state, thereby inhibiting the progression of BPH.


Assuntos
Hiperplasia Prostática , Humanos , Masculino , Animais , Camundongos , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/genética , Hiperplasia Prostática/metabolismo , Interleucina-2 , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Próstata/metabolismo , Modelos Animais de Doenças
5.
J Colloid Interface Sci ; 645: 371-379, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37156145

RESUMO

The sluggish extracellular electron transfer has been known as one of the bottlenecks to limit the power density of microbial fuel cells (MFCs). Herein, molybdenum oxides (MoOx) are doped with various types of non-metal atoms (N, P, and S) by electrostatic adsorption, followed by high-temperature carbonization. The as-prepared material is further used as MFC anode. Results indicate that all different elements-doped anodes can accelerate the electron transfer rate, and the great enhancement mechanism is attributed to synergistic effect of dopped non-metal atoms and the unique MoOx nanostructure, which offers high proximity and a large reaction surface area to promote microbe colonization. This not only enables efficient direct electron transfer but also enriches the flavin-like mediators for fast extracellular electron transfer. This work renders new insights into doping non-metal atoms onto metal oxides toward the enhancement of electrode kinetics at the anode of MFC.


Assuntos
Fontes de Energia Bioelétrica , Molibdênio , Óxidos , Transporte de Elétrons , Eletrodos
6.
Materials (Basel) ; 16(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36984359

RESUMO

The sluggish electron transfer at the interface of microorganisms and an electrode is a bottleneck of increasing the output power density of microbial fuel cells (MFCs). Mo-doped carbon nanofibers (Mo-CNFs) prepared with electrostatic spinning and high-temperature carbonization are used as an anode in MFCs here. Results clearly indicate that Mo2C nanoparticles uniformly anchored on carbon nanowire, and Mo-doped anodes could accelerate the electron transfer rate. The Mo-CNF ΙΙ anode delivered a maximal power density of 1287.38 mW m-2, which was twice that of the unmodified CNFs anode. This fantastic improvement mechanism is attributed to the fact that Mo doped on a unique nanofiber surface could enhance microbial colonization, electrocatalytic activity, and large reaction surface areas, which not only enable direct electron transfer, but also promote flavin-like mediated indirect electron transfer. This work provides new insights into the application of electrospinning technology in MFCs and the preparation of anode materials on a large scale.

7.
Commun Biol ; 5(1): 1105, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261573

RESUMO

Patients with peripheral nerve injury, viral infection or metabolic disorder often suffer neuropathic pain due to inadequate pharmacological options for relief. Developing novel therapies has been challenged by incomplete mechanistic understanding of the cellular microenvironment in sensory nerve that trigger the emergence and persistence of pain. In this study, we report a high resolution transcriptomics map of the cellular heterogeneity of naïve and injured rat sensory nerve covering more than 110,000 individual cells. Annotation reveals distinguishing molecular features of multiple major cell types totaling 45 different subtypes in naïve nerve and an additional 23 subtypes emerging after injury. Ligand-receptor analysis revealed a myriad of potential targets for pharmacological intervention. This work forms a comprehensive resource and unprecedented window into the cellular milieu underlying neuropathic pain and demonstrates that nerve injury is a dynamic process orchestrated by multiple cell types in both the endoneurial and epineurial nerve compartments.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Neuropatia Ciática , Ratos , Animais , Traumatismos dos Nervos Periféricos/genética , Traumatismos dos Nervos Periféricos/metabolismo , Nervo Isquiático/lesões , Ratos Sprague-Dawley , Ligantes , Análise de Célula Única , Neuropatia Ciática/genética , Neuralgia/genética , Neuralgia/metabolismo
8.
Materials (Basel) ; 15(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36295423

RESUMO

Multi-layered NiO nanowires linked with a nitrogen-doped carbon backbone grown directly on flexible carbon cloth (NiO/NCBN/CC) was successfully fabricated with a facile synthetic strategy. The NiO/NCBN/CC was further used as a binding-free electrode for flexible energy storage devices, showing a boosted performance including a high capacitance of 1039.4 F g-1 at 1 A g-1 and an 83.4% capacitance retention ratio. More importantly, after 1500 cycles, the capacitance retention can achieve 72.5% at a current density of 20 A g-1. The excellent electrochemical properties of the as-prepared NiO/NCBN/CC are not only attributed to the multi-layered structure that can help to tender unimpeded channels and accommodate the electrolyte ions around the electrode interface during the charge-discharge process, but is also due to the link between the NiO and N-doped carbon backbone and the nitrogen doping on the carbon substrate, which results in extra defects on the surface that could boost the interfacial electron transfer rate of the electrode.

9.
Oncogene ; 41(37): 4259-4270, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35931888

RESUMO

Intratumoral hypoxia is associated with castration-resistant prostate cancer (CRPC), a lethal disease. FOXA1 is an epithelial transcription factor that is down-regulated in CRPC. We have previously reported that FOXA1 loss induces epithelial-mesenchymal transition (EMT) and cell motility through elevated TGFß signaling. However, whether FOXA1 directly regulates hypoxia pathways of CRPC tumors has not been previously studied. Here we report that FOXA1 down-regulation induces hypoxia transcriptional programs, and FOXA1 level is negatively correlated with hypoxia markers in clinical prostate cancer (PCa) samples. Mechanistically, FOXA1 directly binds to an intragenic enhancer of HIF1A to inhibit its expression, and HIF1A, in turn, is critical in mediating FOXA1 loss-induced hypoxia gene expression. Further, we identify CCL2, a chemokine ligand that modulates tumor microenvironment and promotes cancer progression, as a crucial target of the FOXA1-HIF1A axis. We found that FOXA1 loss leads to immunosuppressive macrophage infiltration and increased cell invasion, dependent on HIF1A expression. Critically, therapeutic targeting of HIF1A-CCL2 using pharmacological inhibitors abolishes FOXA1 loss-induced macrophage infiltration and PCa cell invasion. In summary, our study reveals an essential role of FOXA1 in controlling the hypoxic tumor microenvironment and establishes the HIF1A-CCL2 axis as one mechanism of FOXA1 loss-induced CRPC progression.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Linhagem Celular Tumoral , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Neoplasias de Próstata Resistentes à Castração/patologia , Microambiente Tumoral/genética
10.
J Cell Physiol ; 237(3): 1923-1935, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35023144

RESUMO

The sterile inflammation (SI) of the urinary tract is a common problem requiring serious consideration after prostatectomy. This study mainly focuses on the role of the reactive oxygen species-NLR family, pyrin domain-containing 3 (ROS-NLRP3) signaling pathway in SI after thulium laser resection of the prostate (TmLRP). Urinary cytokines were determined in patients who received TmLRP, and heat shock protein 70 (HSP70) was detected in the resected tissues. The involvement of ROS signaling in HSP70-induced inflammation was explored in THP-1 cells with or without N-acetyl- l-cysteine (NAC) pretreatment. The function of NLRP3 and Caspase-1 was determined by Western blot analysis, enzyme-linked immunosorbent assay (ELISA), and polymerase chain reaction. These phenomena and mechanisms were verified by the beagle models that received TmLRP. Clinical urine samples after TmLRP showed high expression of inflammatory factors and peaked 3-5 days after surgery. The high expression of HSP70 in the resected tissues was observed. After HSP70 stimulation, the expression of ROS, NLRP3, Caspase-1, and interleukin-18 (IL-18) increased significantly and could be reduced by ROS inhibitor NAC. The expression of IL-1ß and IL-18 could be inhibited by NLRP3 or Caspase-1 inhibitors. In beagle models that received TmLRP, HSP70, NLRP3, Caspase-1, IL-1ß, and IL-18 were highly expressed in the wound tissue or urine, and could also be reduced by NAC pretreatment. Activation of the ROS-NLRP3 signaling pathway induces SI in the wound after prostatectomy. Inhibition of this pathway may be effective for clinical prevention and treatment of SI and related complications after prostatectomy.


Assuntos
Inflamação , Proteína 3 que Contém Domínio de Pirina da Família NLR , Próstata , Espécies Reativas de Oxigênio , Acetilcisteína/farmacologia , Animais , Caspase 1/genética , Caspase 1/metabolismo , Cães , Humanos , Inflamassomos/metabolismo , Interleucina-18 , Interleucina-1beta/metabolismo , Lasers , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Próstata/metabolismo , Próstata/cirurgia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Túlio
11.
J Cancer Res Clin Oncol ; 147(11): 3225-3243, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34258652

RESUMO

PURPOSE: FOXA1, as a pioneering transcription factor, has been shown to drive prostate cancer progression. Previous studies showed that FOXA1 expression in prostate cancer was positively associated with cancer angiolymphatic invasion and metastasis. However, the mechanism underlying the correlation between FOXA1 and prostate cancer angiolymphatic invasion and metastasis remains largely unclear. METHODS: Herein, we set out to investigate the role of FOXA1 in the interactions between prostate cancer cells and endothelial cells. Endothelial cells' phenotypes were assessed through CCK-8 assay, Transwell migration assay, and tube formation assay. The angiogenic factors acting on endothelial cells mediated by FOXA1were characterized by RNA-seq, qPCR array, angiogenesis cytokines array, and ELISA assay. The impact of FOXA1 on tumor angiogenesis was examined in a xenograft model in nude mice. The effect of FOXA1 on prostate cancer angiogenesis was validated on a primary prostate cancer tissue microarray. RESULTS: FOXA1 expression in prostate cancer cells promoted endothelial cell proliferation, migration, and tube formation in vitro. Mechanistically, FOXA1 increased pro-angiogenic factors production, including EGF, Endothelin-1, and Endoglin. Moreover, in vivo study showed that FOXA1 facilitated tumor angiogenesis. Furthermore, clinical samples investigation indicated that FOXA1 enhanced prostate cancer angiogenesis. CONCLUSION: Overall, these findings illustrated a tumor angiogenesis-promoting role of FOXA1 in prostate cancer.


Assuntos
Indutores da Angiogênese/metabolismo , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Neoplasias da Próstata/irrigação sanguínea , Animais , Comunicação Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Técnicas de Cocultura , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Expressão Gênica , Células HEK293 , Fator 3-alfa Nuclear de Hepatócito/biossíntese , Fator 3-alfa Nuclear de Hepatócito/genética , Xenoenxertos , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
12.
Front Surg ; 8: 657869, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026814

RESUMO

Background: Until recently, most enucleation techniques of the prostate were performed with the application of morcellator. We introduce a modified enucleation technique of thulium laser with non-morcellator approach, which is about incising and vaporizing remaining prostate tissue instead of a morcellator. Methods: A retrospective evaluation of 223 patients undergoing ThuLEP from January 2014 to December 2015 was performed in our institution. One hundred five of the patients used morcellator while the other 118 used non-morcellator approach. All patients were assessed with the International Prostate Symptom Score (IPSS), quality of life (Qol), ultrasonography, serum prostate-specific antigen (PSA), maximal urine flow rate (Qmax), and postvoid residual urine volume (PVR). We reassessed these parameters at 1-, 3-, 6-, and 12-months after operation. Operative time, perioperative, and postoperative complications were also recorded. Results: Significant improvement was noted in the IPSS, QoL, Qmax, and PVR in both groups at the 12-month follow-up, and assessment showed no differences in these parameters between the two groups. Comparisons of the total operation time and enucleation time demonstrated no significant differences between the two groups. Our non-morcellator approach needed more time to incise and vaporize the enucleated tissue compared to morcellation when the prostate volume was about 40-80 ml (p < 0.05), while it showed a significant lower rate of superficial bladder injury than using morcellator (p < 0.05). There were no significant differences in other complications between the two groups (p > 0.05). Conclusions: Our modified technique is a safe and effective procedure for the treatment of BPH avoiding the potential complications caused by morcellator.

13.
Asian J Androl ; 23(4): 415-420, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33473011

RESUMO

To improve the diagnostic efficiency of prostate cancer (PCa) and reduce unnecessary biopsies, we defined and analyzed the diagnostic efficiency of peripheral zone prostate-specific antigen (PSA) density (PZ-PSAD). Patients who underwent systematic 12-core prostate biopsies in Shanghai General Hospital (Shanghai, China) between January 2012 and January 2018 were retrospectively identified (n = 529). Another group of patients with benign prostatic hyperplasia (n = 100) were randomly preselected to obtain the PSA density of the non-PCa cohort (N-PSAD). Prostate volumes and transition zone volumes were measured using multiparameter magnetic resonance imaging (mpMRI) and were combined with PSA and N-PSAD to obtain the PZ-PSAD from a specific algorithm. Receiver operating characteristic (ROC) curve analysis was used to assess the PCa detection efficiency in patients stratified by PSA level, and the area under the ROC curve (AUC) of PZ-PSAD was higher than that of PSA, PSA density (PSAD), and transition zone PSA density (TZ-PSAD). PZ-PSAD could amend the diagnosis for more than half of the patients with inaccurate transrectal ultrasonography (TRUS) and mpMRI results. When TRUS and mpMRI findings were ambiguous to predict PCa (PIRADS score ≤3), PZ-PSAD could increase the positive rate of biopsy from 21.7% to 54.7%, and help 63.8% (150/235) of patients avoid unnecessary prostate biopsy. In patients whose PSA was 4.0-10.0 ng ml-1, 10.1-20.0 ng ml-1, and >20.0 ng ml-1, the ideal PZ-PSAD cut-off value for predicting clinically significant PCa was 0.019 ng ml-2, 0.297 ng ml-2, and 1.180 ng ml-2, respectively (sensitivity >90%). Compared with PSA, PSAD, and TZ-PSAD, the efficiency of PZ-PSAD for predicting PCa is the highest, leading to fewer missed diagnoses and unnecessary biopsies.


Assuntos
Valor Preditivo dos Testes , Antígeno Prostático Específico/análise , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , China , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Estudos Retrospectivos , Sensibilidade e Especificidade , Estatísticas não Paramétricas
14.
J Exp Clin Cancer Res ; 39(1): 282, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317606

RESUMO

BACKGROUND: Androgen deprivation therapy (ADT) is the backbone of therapy for advanced prostate cancer (PCa). Despite the good initial response, castration resistance and metastatic progression will inevitably occur. Cancer-associated fibroblasts (CAFs) may be implicated in promoting metastasis of PCa after ADT. Our aim is to investigate the role and mechanism of CAFs-derived exosomes involving in metastasis of PCa after ADT. METHODS: PCa cells were co-cultured with exosomes derived from 10 nM dihydrotestosterone (DHT)-treated (simulating the high androgen level of prostate cancer microenvironment) or ethanol (ETOH) -treated (simulating the castration level of prostate cancer microenvironment after ADT) CAFs, and their migration and invasion differences under castration condition were examined both in vitro and in vivo. The miRNA profiles of exosomes derived from DHT-treated CAFs and matched ETOH-treated CAFs were analysed via next generation sequencing. The transfer of exosomal miR-146a-5p from CAFs to PCa cells was identified by fluorescent microscopy. The function and direct target gene of exosomal miR-146a-5p in PCa cells were confirmed through Transwell assays, luciferase reporter, and western blot. RESULTS: Compared with DHT-treated CAFs, exosomes derived from ETOH-treated CAFs dramatically increased migration and invasion of PCa cells under castration condition. MiR-146a-5p level in exosomes from ETOH-treated CAFs was significantly reduced. The loss of miR-146a-5p may strengthen the epithelial-mesenchymal transition (EMT) to accelerate cancer cells metastasis by modulating epidermal growth factor receptor (EGFR)/ERK pathway. CONCLUSIONS: CAFs-derived exosomal miR-146a-5p confers metastasis in PCa cells under ADT through the EGFR/ERK pathway and it may present a new treatment for PCa.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Fibroblastos Associados a Câncer/patologia , Exossomos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/secundário , MicroRNAs/genética , Neoplasias da Próstata/tratamento farmacológico , Animais , Apoptose , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Prognóstico , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Pharmacol Exp Ther ; 374(2): 252-263, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32493725

RESUMO

Deposition of hyperphosphorylated and aggregated tau protein in the central nervous system is characteristic of Alzheimer disease and other tauopathies. Tau is subject to O-linked N-acetylglucosamine (O-GlcNAc) modification, and O-GlcNAcylation of tau has been shown to influence tau phosphorylation and aggregation. Inhibition of O-GlcNAcase (OGA), the enzyme that removes O-GlcNAc moieties, is a novel strategy to attenuate the formation of pathologic tau. Here we described the in vitro and in vivo pharmacological properties of a novel and selective OGA inhibitor, MK-8719. In vitro, this compound is a potent inhibitor of the human OGA enzyme with comparable activity against the corresponding enzymes from mouse, rat, and dog. In vivo, oral administration of MK-8719 elevates brain and peripheral blood mononuclear cell O-GlcNAc levels in a dose-dependent manner. In addition, positron emission tomography imaging studies demonstrate robust target engagement of MK-8719 in the brains of rats and rTg4510 mice. In the rTg4510 mouse model of human tauopathy, MK-8719 significantly increases brain O-GlcNAc levels and reduces pathologic tau. The reduction in tau pathology in rTg4510 mice is accompanied by attenuation of brain atrophy, including reduction of forebrain volume loss as revealed by volumetric magnetic resonance imaging analysis. These findings suggest that OGA inhibition may reduce tau pathology in tauopathies. However, since hundreds of O-GlcNAcylated proteins may be influenced by OGA inhibition, it will be critical to understand the physiologic and toxicological consequences of chronic O-GlcNAc elevation in vivo. SIGNIFICANCE STATEMENT: MK-8719 is a novel, selective, and potent O-linked N-acetylglucosamine (O-GlcNAc)-ase (OGA) inhibitor that inhibits OGA enzyme activity across multiple species with comparable in vitro potency. In vivo, MK-8719 elevates brain O-GlcNAc levels, reduces pathological tau, and ameliorates brain atrophy in the rTg4510 mouse model of tauopathy. These findings indicate that OGA inhibition may be a promising therapeutic strategy for the treatment of Alzheimer disease and other tauopathies.


Assuntos
Inibidores Enzimáticos/farmacologia , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Proteínas tau/metabolismo , Animais , Atrofia/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Inibidores Enzimáticos/uso terapêutico , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Células PC12 , Ratos , Tauopatias/patologia , Tauopatias/fisiopatologia
16.
Curr Top Behav Neurosci ; 45: 209-245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32451955

RESUMO

The α7 nicotinic acetylcholine receptor (nAChR) is a promising target for the treatment of cognitive deficits associated with psychiatric and neurological disorders, including schizophrenia and Alzheimer's disease (AD). Several α7 nAChR agonists and positive allosteric modulators (PAMs) have demonstrated procognitive effects in preclinical models and early clinical trials. However, despite intense research efforts in the pharmaceutical industry and academia, none of the α7 nAChR ligands has been approved for clinical use. This chapter will focus on the α7 nAChR ligands that have advanced to clinical studies and explore the reasons why these agents have not met with unequivocal clinical success.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Receptores Nicotínicos , Esquizofrenia , Disfunção Cognitiva/tratamento farmacológico , Humanos , Agonistas Nicotínicos/farmacologia , Agonistas Nicotínicos/uso terapêutico , Receptor Nicotínico de Acetilcolina alfa7
17.
J Pharmacol Exp Ther ; 373(2): 311-324, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32094294

RESUMO

Treatments for cognitive deficits associated with central nervous system (CNS) disorders such as Alzheimer disease and schizophrenia remain significant unmet medical needs that incur substantial pressure on the health care system. The α7 nicotinic acetylcholine receptor (nAChR) has garnered substantial attention as a target for cognitive deficits based on receptor localization, robust preclinical effects, genetics implicating its involvement in cognitive disorders, and encouraging, albeit mixed, clinical data with α7 nAChR orthosteric agonists. Importantly, previous orthosteric agonists at this receptor suffered from off-target activity, receptor desensitization, and an inverted U-shaped dose-effect curve in preclinical assays that limit their clinical utility. To overcome the challenges with orthosteric agonists, we have identified a novel selective α7 positive allosteric modulator (PAM), BNC375. This compound is selective over related receptors and potentiates acetylcholine-evoked α7 currents with only marginal effect on the receptor desensitization kinetics. In addition, BNC375 enhances long-term potentiation of electrically evoked synaptic responses in rat hippocampal slices and in vivo. Systemic administration of BNC375 reverses scopolamine-induced cognitive deficits in rat novel object recognition and rhesus monkey object retrieval detour (ORD) task over a wide range of exposures, showing no evidence of an inverted U-shaped dose-effect curve. The compound also improves performance in the ORD task in aged African green monkeys. Moreover, ex vivo 13C-NMR analysis indicates that BNC375 treatment can enhance neurotransmitter release in rat medial prefrontal cortex. These findings suggest that α7 nAChR PAMs have multiple advantages over orthosteric α7 nAChR agonists for the treatment of cognitive dysfunction associated with CNS diseases. SIGNIFICANCE STATEMENT: BNC375 is a novel and selective α7 nicotinic acetylcholine receptor (nAChR) positive allosteric modulator (PAM) that potentiates acetylcholine-evoked α7 currents in in vitro assays with little to no effect on the desensitization kinetics. In vivo, BNC375 demonstrated robust procognitive effects in multiple preclinical models across a wide exposure range. These results suggest that α7 nAChR PAMs have therapeutic potential in central nervous system diseases with cognitive impairments.


Assuntos
Benzetônio/farmacologia , Clorobenzenos/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Regulação Alostérica , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cognição/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Macaca mulatta , Masculino , Neurotransmissores/metabolismo , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Escopolamina/farmacologia
18.
Front Oncol ; 10: 584505, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33425737

RESUMO

Docetaxel is a first-line chemotherapy for the treatment of patients with castration-resistant prostate cancer (CRPC). Despite the good initial response of docetaxel, drug resistance will inevitably occur. Mechanisms underlying docetaxel resistance are not well elaborated. Endothelial cells (ECs) have been implicated in the progression and metastasis of prostate cancer. However, little attention has been paid to the role of endothelial cells in the development of docetaxel resistance in prostate cancer. Here, we sought to investigate the function and mechanism of endothelial cells involving in the docetaxel resistance of prostate cancer. We found that endothelial cells significantly promoted the proliferation of prostate cancer cells and decreased their sensitivity to docetaxel. Mechanistically, basic fibroblast growth factor (FGF2) secreted by endothelial cells leads to the upregulation of ETS related gene (ERG) expression and activation of the Akt/mTOR signaling pathway in prostate cancer cells to promote docetaxel resistance. In summary, these findings demonstrate a microenvironment-dependent mechanism mediating chemoresistance of prostate cancer and suggest that targeting FGF/FGFR signaling might represent a promising therapeutic strategy to overcome docetaxel resistance.

19.
Int J Med Microbiol ; 309(8): 151337, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31477487

RESUMO

Salmonella Enteritidis (SE) is a highly adapted pathogen causing severe economic losses in the poultry industry worldwide. Chickens infected by SE are a major source of human food poisoning. Vaccination is an effective approach to control SE infections. This study evaluated the immunogenicity and protective efficacy of a SE sptP deletion mutant (C50336ΔsptP) as a live attenuated vaccine (LAV) candidate in chickens. 14 day-old specific pathogen-free (SPF) chickens were intramuscularly immunized with various doses of C50336ΔsptP. Several groups of chickens were challenged with the virulent wild-type SE strain Z-11 via the same route at 14 days post vaccination. Compared to the control group, the groups vaccinated with 1 × 106, 1 × 107 and 1 × 108 colony-forming units (CFU) of C50336ΔsptP exhibited no clinical symptoms after immunization. Only slight pathological changes occurred in the organs of the 1 × 109 CFU vaccinated group. C50336ΔsptP bacteria were cleared from the organs of immunized chickens within 14 days after vaccination. Lymphocyte proliferation and serum cytokine analyses indicated that significant cellular immune responses were induced after the vaccination of C50336ΔsptP. Compared to the control group, specific IgG antibody levels increased significantly in vaccinated chickens, and the levels increased markedly after the challenge. The 1 × 107, 1 × 108, and 1 × 109 CFU vaccinated chickens groups showed no clinical symptoms or pathological changes, and no death after the lethal challenge. Whereas severe clinical signs of disease and pathological changes were observed in the control group chickens after the challenge. These results suggest that a single dose of C50336ΔsptP could be an effective LAV candidate to against SE infection in chickens.


Assuntos
Proteínas de Bactérias/genética , Imunogenicidade da Vacina , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/prevenção & controle , Vacinas contra Salmonella/imunologia , Deleção de Sequência , Animais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/imunologia , Galinhas , Citocinas/sangue , Imunoglobulina G/sangue , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/imunologia , Salmonella enteritidis/genética , Salmonella enteritidis/imunologia , Organismos Livres de Patógenos Específicos , Vacinação/veterinária , Vacinas Atenuadas/imunologia
20.
J Med Chem ; 62(22): 10062-10097, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31487175

RESUMO

Inhibition of O-GlcNAcase (OGA) has emerged as a promising therapeutic approach to treat tau pathology in neurodegenerative diseases such as Alzheimer's disease and progressive supranuclear palsy. Beginning with carbohydrate-based lead molecules, we pursued an optimization strategy of reducing polar surface area to align the desired drug-like properties of potency, selectivity, high central nervous system (CNS) exposure, metabolic stability, favorable pharmacokinetics, and robust in vivo pharmacodynamic response. Herein, we describe the medicinal chemistry and pharmacological studies that led to the identification of (3aR,5S,6S,7R,7aR)-5-(difluoromethyl)-2-(ethylamino)-3a,6,7,7a-tetrahydro-5H-pyrano[3,2-d]thiazole-6,7-diol 42 (MK-8719), a highly potent and selective OGA inhibitor with excellent CNS penetration that has been advanced to first-in-human phase I clinical trials.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Cães , Descoberta de Drogas , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/farmacocinética , Humanos , Macaca mulatta , Masculino , Células PC12 , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Tauopatias/tratamento farmacológico , beta-N-Acetil-Hexosaminidases/química , beta-N-Acetil-Hexosaminidases/metabolismo
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