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1.
J Cell Biochem ; 122(11): 1749-1760, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34383347

RESUMO

Bone is the common extra-hepatic site for cancer metastasis. Hepatic cancer is associated with a higher incidence of pathological fracture. However, this important regulatory mechanism remains unexplored. Thus, exosome-mediated cell-cell communication between hepatocellular cancer and bone might be key to osteolytic bone destruction. Huh-7 exosomes were characterized for size and exosome marker expressions (CD63, Alix). Exosome mediated osteoclast differentiation in the RAW 264.7 cells was monitored from day 1 to 6 and multinucleated osteoclast formation and bone resorption activity were analyzed. The osteoclastogenic factor expressions in the exosomes and osteoclast differentiation markers such as tumor necrosis factor receptor 6 (TRAF6), nuclear factor κB (NF-κB), nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), and cathepsin K (CTSK) were analyzed using western blot. Exosomes released by liver cancer cells (Huh-7) promoted osteoclast differentiation in RAW 264.7 cells. Analysis of osteoclastogenic factors in the exosomes showed that exosomes were specifically enriched with tumor necrosis factor α (TNF-α). Huh-7 exosomes promoted osteoclast differentiation by significantly increasing the number of TRAP-positive multi nucleated osteoclasts and resorption pits. Importantly, exosomes upregulated osteoclast markers TRAF6, NF-κB, and CTSK expressions. Further, neutralizing exosomal TNF-α reverted exosome-mediated osteoclast differentiation in RAW 264.7 cells. Collectively, our findings show that cellular communication of exosomal TNF-α from hepatocellular cancer cells (Huh-7) regulates osteoclast differentiation through NF-κB/CTSK/TRAP expressions. Thus, exosomal TNF-α might act as an important therapeutic target to prevent hepatocellular cancer mediated pathological bone disease.


Assuntos
Diferenciação Celular/fisiologia , Exossomos/metabolismo , Neoplasias Hepáticas/patologia , Osteoclastos/citologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Catepsina K/metabolismo , Meios de Cultivo Condicionados/farmacologia , Exossomos/patologia , Humanos , Camundongos , NF-kappa B/metabolismo , Células RAW 264.7 , Fosfatase Ácida Resistente a Tartarato/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
2.
FASEB J ; 34(11): 15300-15313, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32959404

RESUMO

The aryl hydrocarbon receptor (AhR) is a ligand-dependent-activated transcriptional factor that regulates the metabolism of xenobiotic and endogenous compounds. Recent studies have shown that AhR is a novel master regulator of the mucosal immune system, including lungs and intestine. To elucidate the role of AhR in chronic severe asthma, AhR wild-type and knockout mice (AhR-/- ) were sensitized and challenged with ovalbumin for 4 weeks. To uncover the underlying mechanisms, inflammatory cells profile and cytokines production were analyzed in bronchial lavage fluid (BALF) and lung tissue. Compared to wild-type mice, AhR-/- mice had exacerbated asthma symptoms, including airway inflammation, mucus production, airway hyperresponsiveness, and airway remodeling. BALF monocytes, neutrophils, eosinophils, and lymphocytes were all enhanced in OVA-immunized AhR-/- mice. In OVA-immunized AhR-/- mice, T helper (Th) 17 cell-specific cytokine IL-17A, as well as airway remodeling factors, including epithelial-mesenchymal transition (EMT) markers and vascular endothelial growth factor (VEGF), were all enhanced in lung tissue. Moreover, human cohort studies showed that AhR gene expression in bronchial epithelial cells decreases in severe asthma patients. Loss of AhR leads to worsening of allergic asthma symptoms, indicating its importance in maintaining normal lung function and mediating disease severity.


Assuntos
Asma/complicações , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal , Inflamação/etiologia , Receptores de Hidrocarboneto Arílico/fisiologia , Hipersensibilidade Respiratória/etiologia , Células Th17/imunologia , Animais , Asma/induzido quimicamente , Movimento Celular , Citocinas/metabolismo , Feminino , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina/toxicidade , Hipersensibilidade Respiratória/metabolismo , Hipersensibilidade Respiratória/patologia
3.
Part Fibre Toxicol ; 18(1): 4, 2021 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-33422125

RESUMO

BACKGROUND: Depending on their distinct properties, titanium dioxide nanoparticles (TiO2-NPs) are manufactured extensively and widely present in our daily necessities, with growing environmental release and public concerns. In sunscreen formulations, supplementation of TiO2-NPs may reach up to 25% (w/w). Ocular contact with TiO2-NPs may occur accidentally in certain cases, allowing undesirable risks to human vision. This study aimed to understand the barrier integrity of retinal endothelial cells in response to TiO2-NP exposure. bEnd.3 cells and human retinal endothelial cells (HRECs) were exposed to TiO2-NP, followed by examination of their tight junction components and functions. RESULTS: TiO2-NP treatment apparently induced a broken structure of the junctional plaques, conferring decreased transendothelial electrical resistance, a permeable paracellular cleft, and improved cell migration in vitro. This might involve rapid activation of metalloproteinase, a disintegrin and metalloproteinase 17 (ADAM17), and ADAM17-mediated claudin-5 degradation. For the in vivo study, C57BL/6 mice were administered a single dose of TiO2-NP intravitreally and then subjected to a complete ophthalmology examination. Fluorescein leakage and reduced blood flow at the optical disc indicated a damaged inner blood-retinal barrier induced by TiO2-NPs. Inappreciable change in the thickness of retinal sublayers and alleviated electroretinography amplitude were observed in the TiO2-NP-treated eyes. CONCLUSIONS: Overall, our data demonstrate that TiO2-NP can damage endothelial cell function, thereby affecting retinal electrophysiology.


Assuntos
Nanopartículas Metálicas , Titânio/toxicidade , Animais , Barreira Hematorretiniana , Claudina-5 , Eletrofisiologia , Células Endoteliais , Nanopartículas Metálicas/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas
4.
Int J Mol Sci ; 22(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34576152

RESUMO

Aryl hydrocarbon receptor (AHR) genomic pathway has been well-characterized in a number of respiratory diseases. In addition, the cytoplasmic AHR protein may act as an adaptor of E3 ubiquitin ligase. In this study, the physiological functions of AHR that regulate cell proliferation were explored using the CRISPR/Cas9 system. The doubling-time of the AHR-KO clones of A549 and BEAS-2B was observed to be prolonged. The attenuation of proliferation potential was strongly associated with either the induction of p27Kip1 or the impairment in mitogenic signal transduction driven by the epidermal growth factor (EGF) and EGF receptor (EGFR). We found that the leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1), a repressor of EGFR, was induced in the absence of AHR in vitro and in vivo. The LRIG1 tends to degrade via a proteasome dependent manner by interacting with AHR in wild-type cells. Either LRIG1 or a disintegrin and metalloprotease 17 (ADAM17) were accumulated in AHR-defective cells, consequently accelerating the degradation of EGFR, and attenuating the response to mitogenic stimulation. We also affirmed low AHR but high LRIG1 levels in lung tissues of chronic obstructive pulmonary disease (COPD) patients. This might partially elucidate the sluggish tissue repairment and developing inflammation in COPD patients.


Assuntos
Receptores ErbB/metabolismo , Glicoproteínas de Membrana/metabolismo , Mitógenos/metabolismo , Proteólise , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Células A549 , Proteína ADAM17/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Clonais , Fator de Crescimento Epidérmico/farmacologia , Humanos , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteólise/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Regulação para Cima/efeitos dos fármacos
5.
J Cell Biochem ; 121(11): 4522-4534, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32030803

RESUMO

Autophagy, an important cellular homeostatic mechanism regulates cell survival under stress and protects against acute kidney injury. However, the role of long noncoding RNA (lncRNA) in autophagy regulation in renal tubular cells (HK-2) is unclear. The study was aimed to understand the importance of lncRNA in hypoxia-induced autophagy in HK-2 cells. LncRNA eosinophil granule ontogeny transcript (EGOT) was identified as autophagy-associated lncRNA under hypoxia. The lncRNA EGOT expression was significantly downregulated in renal tubular cells during hypoxia-induced autophagy. Gain- and loss-of-EGOT functional studies revealed that EGOT overexpression reduced autophagy by downregulation of ATG7, ATG16L1, LC3II expressions and LC 3 puncta while EGOT knockdown reversed the suppression of autophagy. Importantly, RNA-binding protein, (ELAVL1)/Hu antigen R (HuR) binds and stabilizes the EGOT expression under normoxia and ATG7/16L1 expressions under hypoxia. Furthermore, HuR mediated stabilization of ATG7/16L1 expressions under hypoxia causes a decline in EGOT levels and thereby promotes autophagy. Altogether, the study first reveals the functional interplay of lncRNA EGOT and HuR on the posttranscriptional regulation of the ATG7/16L1 expressions. Thus, the HuR/EGOT/ATG7/16L1 axis is crucial for hypoxia-induced autophagy in renal tubular cells.


Assuntos
Autofagia , Proteína Semelhante a ELAV 1/metabolismo , Hipóxia/fisiopatologia , Túbulos Renais/patologia , RNA Longo não Codificante/genética , Proliferação de Células , Células Cultivadas , Proteína Semelhante a ELAV 1/genética , Humanos , Túbulos Renais/metabolismo
6.
Cell Biol Toxicol ; 36(3): 223-242, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31748929

RESUMO

The aryl hydrocarbon receptor (AHR) is a ligand-activated receptor that regulates the metabolism of several xenobiotics and participates in ocular inflammation. Although severe inflammation is a major risk of retinal damage, the underlying mechanism is not well established. In this study, to elucidate how AHR mediates inflammation homeostasis, we hypothesized that AHR expression may diminish during long-term exposure to benzo [a] pyrene (B [a]P), a carcinogen in cigarette smoke. The blockage of AHR function considerably impaired suppressor of cytokine signaling 3 (SOCS3) negative feedback regulation and upregulated B [a]P-induced pro-inflammation. Signal transducer and activator of transcription 3 (STAT3) was activated by B [a] P due to AHR dysfunction in human adult retinal pigment epithelial cells (ARPE-19). The STAT3-inducible element revealed higher activity in AHR knockout cells with B [a] P treatment, but not in wild type ARPE-19 cells. Moreover, AHR dysfunction led to STAT3 hypo-ubiquitination and changed the STAT3-SOCS3 interaction. Increased STAT3-SOCS3 complex during AHR dysfunction by B [a] P was suppressed by nifuroxazide in ARPE-19 cells. Furthermore, the in vivo results showed that STAT3 inhibition during AHR impairment by long-term B [a] P exposure preserved the retina thickness and reversed the visual function in male C57Bl/6 mice. Overall, long-term B [a] P exposure may attenuate AHR function, dysregulating the homeostasis of the SOCS3-STAT3 axis with intensive STAT3 activation. This finding is significant given that the disintegration of the AHR-SOCS3 axis is a sensitive factor involved in AMD-like lesion development in the retina, revealing that the low AHR level may be associated with cigarette smoking or xenobiotics exposure, causing retina inflammation and damage.


Assuntos
Receptores de Hidrocarboneto Arílico/metabolismo , Fator de Transcrição STAT3/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Animais , Benzo(a)pireno/toxicidade , Carcinógenos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Hidrocarboneto Arílico/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Ativação Transcricional
8.
Part Fibre Toxicol ; 16(1): 37, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619255

RESUMO

BACKGROUND: Gold nanoparticles (Au-NPs) have extensive applications in electronics and biomedicine, resulting in increased exposure and prompting safety concerns for human health. After absorption, nanoparticles enter circulation and effect endothelial cells. We previously showed that exposure to Au-NPs (40-50 nm) collapsed endothelial tight junctions and increased their paracellular permeability. Inhaled nanoparticles have gained significant attention due to their biodistribution in the brain; however, little is known regarding their role in cerebral edema. The present study investigated the expression of aquaporin 1 (AQP1) in the cerebral endothelial cell line, bEnd.3, stimulated by Au-NPs. RESULTS: We found that treatment with Au-NPs induced AQP1 expression and increased endothelial permeability to water. Au-NP exposure rapidly boosted the phosphorylation levels of focal adhesion kinase (FAK) and AKT, increased the accumulation of caveolin 1 (Cav1), and reduced the activity of extracellular regulated protein kinases (ERK). The inhibition of AKT (GDC-0068) or FAK (PF-573228) not only rescued ERK activity but also prevented AQP1 induction, whereas Au-NP-mediated Cav1 accumulation remained unaltered. Neither these signaling molecules nor AQP1 expression responded to Au-NPs while Cav1 was silenced. Inhibition of ERK activity (U0126) remarkably enhanced Cav1 and AQP1 expression in bEnd.3 cells. These data demonstrate that Au-NP-mediated AQP1 induction is Cav1 dependent, but requires the repression on ERK activity. Mice receiving intranasally administered Au-NPs displayed cerebral edema, significantly augmented AQP1 protein levels; furthermore, mild focal lesions were observed in the cerebral parenchyma. CONCLUSIONS: These data suggest that the subacute exposure of nanoparticles might induce cerebral edema, involving the Cav1 dependent accumulation on endothelial AQP1.


Assuntos
Aquaporina 1/metabolismo , Edema Encefálico/induzido quimicamente , Caveolina 1/metabolismo , Células Endoteliais/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Ouro/toxicidade , Exposição por Inalação/efeitos adversos , Nanopartículas Metálicas/toxicidade , Animais , Edema Encefálico/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Ouro/química , Humanos , Masculino , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos ICR , Tamanho da Partícula , Propriedades de Superfície , Água/metabolismo
9.
Int J Mol Sci ; 20(1)2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30609861

RESUMO

Chloramphenicol is an inexpensive and excellent bactericidal antibiotic. It is used to combat anaerobic infections in the Third World countries, whereas its systemic application has been abandoned in developed countries. However, in recent years, clinicians have reintroduced chloramphenicol in clinical practice. In this study, chloramphenicol was found to repress the oxygen-labile transcription factor, hypoxia inducible factor-1 alpha (HIF-1α), in hypoxic A549 and H1299 cells. Furthermore, it suppressed the mRNA levels of vascular endothelial growth factor (VEGF) and glucose transporter 1, eventually decreasing VEGF release. Chloramphenicol initiated the autophagy pathway in treated cells, as observed by the increase in formation of Atg12-Atg5 conjugates, and in beclin-1 and LC3-II levels. The chloramphenicol-mediated HIF-1α degradation was completely reverted by autophagic flux blockage. In HIF-1α-overexpressing cells, the formation of HIF-1α/SENP-1 (Sentrin/SUMO-specific protease 1) protein complex seemed to facilitate the escape of HIF-1α from degradation. Chloramphenicol inhibited HIF-1α/SENP-1 protein interaction, thereby destabilizing HIF-1α protein. The enhancement in HIF-1α degradation due to chloramphenicol was evident during the incubation of the antibiotic before hypoxia and after HIF-1α accumulation. Since HIF-1α plays multiple roles in infections, inflammation, and cancer cell stemness, our findings suggest a potential clinical value of chloramphenicol in the treatment of these conditions.


Assuntos
Autofagia/efeitos dos fármacos , Cloranfenicol/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células A549 , Proteína Beclina-1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisteína Endopeptidases/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Ligação Proteica , Proteína Sequestossoma-1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Arch Toxicol ; 91(5): 2165-2178, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27752740

RESUMO

Aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, has been studied extensively in carcinogenesis through the genomic pathway. In recent years, AHR has also been reported to exert positive or negative effects on epithelial-mesenchymal transition (EMT), the crucial step in tumor malignant progression. However, the detailed mechanism remains controversial. Analysis of AHR-expression levels in non-small cell lung cancer cell lines and lung cancer tissues revealed an inverse correlation between AHR protein levels and tumor cell invasion and metastasis. Overexpression of wild-type AHR in H1299 cells (AHR poorly expressed, potently invasive) not only accelerated mesenchymal vimentin degradation, but also prevented cell invasion in vitro and in vivo. In the absence of AHR agonists, the overexpressed AHR protein was predominantly localized in the cytoplasm, where it interacted with vimentin and functioned as an E3 ubiquitin ligase. A 6-h incubation with the proteasome inhibitor MG-132 fully rescued vimentin from AHR-mediated proteasomal degradation. In AHR-overexpressing H1299 cells, either vimentin degradation or invasive suppression could be reversed when glycogen synthase kinase 3 beta (GSK3ß) was inactivated by CHIR-99021 treatment. In contrast, silencing of AHR in A549 cells (AHR highly expressed, weakly invasive) resulted in the downregulation of epithelial biomarkers (E-cadherin and claudin-1), augmentation of mesenchymal vimentin level, and GSK3ß Ser-9 hyper-phosphorylation, which led to enhanced invasiveness. This work demonstrates that cytoplasmic, resting AHR protein may act as an EMT suppressor via a non-genomic pathway. Depletion of cytoplasmic AHR content represents a potential switch for EMT, thereby leading to the scattering of tumor cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Pulmonares/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Vimentina/metabolismo , Idoso , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Citoplasma/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Arch Toxicol ; 88(3): 659-71, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24292262

RESUMO

Hypoxia-mediated stress responses are important in tumor progression, especially when tumor growth causes the tumor to become deprived of its blood supply. The oxygen-labile transcription factor hypoxia-inducible factor-1 alpha (HIF-1α) plays a critical role in regulating hypoxia stress-related gene expression and is considered a novel therapeutic target. Lung adenocarcinoma cell lines were exposed to minocycline, followed by incubation at hypoxic condition for 3-6 h. Here, we show that minocycline, a second-generation tetracycline, can induce HIF-1α proteasomal degradation under hypoxia by increasing the expression prolyl hydroxylase-2 and HIF-1α/von Hippel-Lindau protein interaction, thereby overcoming hypoxia-induced HIF-1α stabilization. Neither repression of hypoxia-induced phosphatidylinositol-3 kinase/Akt/mammalian target of rapamycin pathway nor inhibition of Hsp90 was required for minocycline-induced HIF-1α degradation. The HIF-1α degradation-enhancing effect of minocycline was evident in both cancerous and primary cells. Minocycline-pretreated, hypoxia-conditioned cells showed a clear reduction in hypoxia response element reporter expression and amelioration of vascular endothelial growth factor C/D (VEGF-C/D), matrix metalloproteinase 2, and glucose transporter 1 expression. By decreasing VEGF secretion of cancerous cells, minocycline could suppress endothelial cell neovasculogenesis. These findings suggest a novel application of minocycline in the treatment of tumor angiogenesis as well as hypoxia-related diseases.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Minociclina/farmacologia , Neovascularização Patológica/tratamento farmacológico , Prolil Hidroxilases/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Transportador de Glucose Tipo 1/genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator C de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo
12.
Biochem Pharmacol ; 215: 115700, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37482199

RESUMO

Diabetic retinopathy (DR) is a severe consequence of long-term diabetes mellitus and may lead to vision loss. Retinal pigment epithelial (RPE) cells are a diverse group of retinal cells with varied metabolic and functional roles. In hypoxic conditions, RPE cells have been shown to produce angiogenic factors, such as vascular endothelial growth factor (VEGF), which is regulated by hypoxia-inducible factor 1-alpha (HIF1A). VEGF plays a crucial role in angiogenesis in DR. In the present study, we investigated whether azatyrosine-phenylbutyric hydroxamide (AZP) has therapeutic effect on DR therapy. In this study, we treated high glucose-activated human retinal pigment epithelial cells (ARPE-19) with and without AZP. The effector proteins were evaluated using western blotting. In the in vivo study, AZP was administered to the db/db mice as a DR animal model. Moreover, invasive imaging techniques such as optical coherence tomography (OCT), fundus photography, and fundus fluorescein angiography (FFA) were performed on the mice to assess DR progression. We found that treatment of AZP for 12 weeks reversed increasing DR retinal alterations in db/db mice, decreasing vascular density, retinal blood perfusion, retinal thickness, decreasing DR lesion, lipofuscin accumulation, HIF1A, VEGF, and inflammation factor expression. In addition, AZP treatment could activate the aryl hydrocarbon receptor AHR and reverse the high-glucose-induced HIF1A and VEGF in ARPE-19 cells and db/db mice. In conclusion, AZP activated AHR while inhibiting HIF1A and VEGF. This study indicates that AZP may be a promising therapeutic agent for treating DR.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Camundongos , Humanos , Animais , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Glucose , Pigmentos da Retina/uso terapêutico
13.
Fluids Barriers CNS ; 20(1): 31, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095509

RESUMO

Blue light is part of the natural light spectrum that emits high energy. Currently, people are frequently exposed to blue light from 3C devices, resulting in a growing incidence of retinopathy. The retinal vasculature is complex, and retinal vessels not only serve the metabolic needs of the retinal sublayers, but also maintain electrolyte homeostasis by forming the inner blood-retinal barrier (iBRB). The iBRB, which is primarily composed of endothelial cells, has well-developed tight junctions. However, with exposure to blue light, the risks of targeting retinal endothelial cells are currently unknown. We found that endothelial claudin-5 (CLDN5) was rapidly degraded under blue light, coinciding with the activation of a disintegrin and metalloprotease 17 (ADAM17), even at non-cytotoxic lighting. An apparently broken tight junction and a permeable paracellular cleft were observed. Mice exposed to blue light displayed iBRB leakage, conferring attenuation of the electroretinogram b-wave and oscillatory potentials. Both pharmacological and genetic inhibition of ADAM17 remarkably alleviated CLDN5 degradation induced by blue light. Under untreated condition, ADAM17 is sequestered by GNAZ (a circadian-responsive, retina-enriched inhibitory G protein), whereas ADAM17 escapes from GNAZ by blue light illuminance. GNAZ knockdown led to ADAM17 hyperactivation, CLDN5 downregulation, and paracellular permeability in vitro, and retinal damage mimicked blue light exposure in vivo. These data demonstrate that blue light exposure might impair the iBRB by accelerating CLDN5 degradation through the disturbance of the GNAZ-ADAM17 axis.


Assuntos
Barreira Hematorretiniana , Células Endoteliais , Camundongos , Animais , Barreira Hematorretiniana/metabolismo , Claudina-5/metabolismo , Células Endoteliais/metabolismo , Retina/metabolismo , Junções Íntimas/metabolismo
14.
Exp Dermatol ; 21(7): 546-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22716253

RESUMO

Ageing is a complex and multifactorial process resulting in several functional and aesthetic changes to the skin. We found that α-Naphthoflavone (α-NF) concentration-dependently induced pro-collagen type I protein expression and inhibited MMP-1 protein expression, in both normal and UVB-irradiated cells. SB431542 and SIS3 - inhibitors of TGF-ß and Smad3, respectively - significantly alleviate α-NF-caused response of MMP-1 and pro-collagen. LY294002 (PI3K inhibitor) can reverse α-NF-induced ERK, Akt, Smad-3 activation, pro-collagen synthesis and α-NF-suppressed AP-1 activation. PD (ERK inhibitor) was not involved in pro-collagen generation and MMP-1 inhibition. We concluded that α-NF promotes pro-collagen production and inhibits MMP-1 expression via the activation of a PI3K/Akt/Smad-3 pathway in normal and UVB-irradiated human skin fibroblasts, while TGF-ß may play an important role in transducing this pathway. These results suggest that α-NF, a natural plant product, has the potential to become a novel anti-ageing skin application.


Assuntos
Benzoflavonas/farmacologia , Colágeno Tipo I/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Envelhecimento da Pele/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Pró-Colágeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteína Smad3/metabolismo , Raios Ultravioleta
15.
Nutrients ; 14(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36145135

RESUMO

High fructose intake has been implicated in obesity and metabolic syndrome, which are related to increased cardiovascular mortality. However, few studies have experimentally examined the role of renin-angiotensin system blockers and calcium channel blockers (CCB) in obesity. We investigated the effects of valsartan (an angiotensin II receptor blocker) and amlodipine (a CCB) on lipolysis through the potential mechanism of PU.1 inhibition. We observed that high fructose concentrations significantly increased adipose size and triglyceride, monoacylglycerol lipase, adipose triglyceride lipase, and stearoyl-CoA desaturase-1 (SCD1), activating transcription factor 3 and PU.1 levels in adipocytes in vitro. Subsequently, PU.1 inhibitor treatment was able to reduce triglyceride, SCD1, and PU.1 levels. In addition, elevated levels of triglyceride and PU.1, stimulated by a high fructose concentration, decreased with valsartan and amlodipine treatment. Overall, these findings suggest that high fructose concentrations cause triacylglycerol storage in adipocytes through PU.1-mediated activation. Furthermore, valsartan and amlodipine treatment reduced triacylglycerol storage in adipocytes by inhibiting PU.1 activation in high fructose concentrations in vitro. Thus, the benefits of valsartan and amlodipine in lipolysis may be through PU.1 inhibition in fructose-induced adiposity, and PU.1 inhibition might have a potential therapeutic role in lipolysis in fructose-induced obesity.


Assuntos
Anlodipino , Hipertensão , Fator 3 Ativador da Transcrição/metabolismo , Adiposidade , Anlodipino/farmacologia , Antagonistas de Receptores de Angiotensina , Anti-Hipertensivos/farmacologia , Pressão Sanguínea , Bloqueadores dos Canais de Cálcio/farmacologia , Frutose/efeitos adversos , Humanos , Hipertensão/tratamento farmacológico , Lipase/metabolismo , Lipólise , Monoacilglicerol Lipases/metabolismo , Obesidade/tratamento farmacológico , Obesidade/etiologia , Estearoil-CoA Dessaturase/metabolismo , Tetrazóis/farmacologia , Tetrazóis/uso terapêutico , Triglicerídeos/farmacologia , Valsartana/metabolismo , Valsartana/farmacologia , Valsartana/uso terapêutico
16.
Front Med (Lausanne) ; 9: 997379, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36203771

RESUMO

Whether valacyclovir-associated neurotoxicity (VAN) occurs more frequently in patients with end-stage renal disease (ESRD) on dialysis is unknown. This is the first population-based study to examine the risk of VAN associated with ESRD patients on dialysis. Among 2,284,800 patients diagnosed as having herpes zoster from 2002 to 2016, patients with ESRD on dialysis and individuals with normal renal function were enrolled in this study. Following propensity score matching, we compared the risk of altered mental status between valacyclovir users and non-users in the ESRD and normal renal function cohorts over a 30-day follow-up period. In the ESRD cohort, the incidence of altered mental status was 1.68 and 0.52 per 1,000 person-day in valacyclovir users and non-users, respectively, with an adjusted hazard ratio (HR) of 3.22 (95% confidence interval [CI]: 2.04-4.99, P < 0.001). The incidence of altered mental status of valacyclovir users on hemodialysis (HD) and peritoneal dialysis (PD) was higher than that of non-users. The adjusted HR was 3.20 (95% CI: 1.98-5.15, P < 0.001) for those on HD and 3.44 (95% CI: 1.13-10.49, P = 0.030) for those with PD. However, altered mental status was not observed in patients on HD receiving ≤500 mg of valacyclovir three times per week or in those on PD receiving ≤500 mg of valacyclovir per day. The findings demonstrate that adjusting the valacyclovir dosage and monitoring VAN in patients with HD and PD who have herpes zoster is crucial.

17.
Front Oncol ; 12: 840142, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600378

RESUMO

Objective: Plasma dipeptidyl peptidase-4 (DPP4) levels were significantly lower in patients with colorectal and liver cancers, and animal studies also showed DPP4 inhibitors (DPP4is) have procarcinogenic effects in colorectal cancer. Until now, whether DPP4is therapy affects the progression of liver cancer and colorectal cancer in patients with T2DM has not been well investigated. We investigated the association between cumulative defined daily dose (cDDD) of DPP4is exposure and risks of liver and colorectal cancers in patients with type 2 diabetes. Materials and Methods: We identified 268,520 patients with diabetes receiving DPP4is as second-line agents between March 1, 2009, and December 31, 2013, from Taiwan's National Health Insurance Research Database, Taiwan Cancer Registry, and National Death Registry of Taiwan. The amount of DPP4is were divided into three groups (low, medium, and high) based on the interquartile range of the cDDD of the DPP4is. Results: The data showed that the low cDDD of DPP-4is was associated with a reducing risk of colorectal cancer [adjusted odds ratio (OR), 0.49; 95% CI, 0.32-0.75; P=0.001]. However, the high cDDD of DPP-4is was associated with an increasing risk of colorectal cancer (adjusted OR, 1.86; 95% CI, 1.32-2.61; P<0.001). No association between DPP4is use and liver cancer risk was observed. Conclusions: This nested case study revealed a J-shaped association between the cDDD of DPP-4is and colorectal cancer risk, but not liver cancer risk. Therefore, the effects of long-term DPP4is use on colorectal cancer risk warrant further study.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34770192

RESUMO

Periodontitis is the most prevalent chronic inflammatory oral disease that is characterized by tooth loss and is commonly associated with several systemic inflammatory diseases. Some epidemiological studies suggest that those suffering from periodontitis might be at a greater risk of developing gastric Helicobacter pylori (Hp) infection; however, evidence that showing the association between periodontitis and the risk of gastric Hp infection is less clear. We conducted a large-scale, population-based study in Taiwan with a 13-year follow-up period to evaluate the risk of gastric Hp in a periodontitis patient cohort. To conduct this study, we used epidemiological data from the Taiwanese Longitudinal National Health Insurance Research Database (NHIRD) from 2000 to 2013. We selected 134,474 participants (64,868 males and 69,606 females with a minimum age of 20 years), with and without periodontitis, and matched patient cohort groups for age, sex, index year, and co-morbidities. The Cox proportional hazards regression model was used to examine the risk of gastric Hp infection in patients with periodontitis. Patients with periodontitis exhibited a higher risk of developing gastric Hp infection compared to those individuals/groups without periodontitis (1.35 vs. 0.87 per 1000 person-years, adjusted the hazards ratio (aHR 1.52), and 95% confidence intervals (CIs) 1.38-1.67, p < 0.001). The risk of gastric Hp infection persisted even after stratifying by age (aHR = 1.96 (1.79-2.13) for 50-64 years and 1.70 (1.49-1.94) for ≥65 years), gender (aHR = 1.20 (1.11-1.29) for men), and presence of comorbidities of hypertension (aHR = 1.24 (1.11-1.38)), hyperlipidemia (aHR = 1.28 (1.14-1.42)), COPD (aHR = 1.45 (1.31-1.61)), CLD (aHR = 1.62 (1.47-1.77)) and CKD (aHR = 1.44 (1.04-1.99)). Overall, our findings showed that periodontitis patients have a greater risk for gastric Hp than individuals without periodontitis. Clinicians should perform regular good oral hygiene practices, along with newer treatments, for patients with periodontitis, especially those at higher risk of gastric Hp infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Periodontite , Adulto , Estudos de Coortes , Comorbidade , Feminino , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Periodontite/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
19.
Nutrients ; 12(7)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708678

RESUMO

Non-insulin-dependent diabetes mellitus (NIDDM) is a common metabolic disorder worldwide. In addition to the chief feature of long-standing hyperglycemia, dyslipidemia, hyperinsulinemia, and a number of complications develop in parallel. It is believed that an adequate control of blood glucose levels can cause these complications to go into remission. This study was performed to evaluate the antidiabetic activity of Eurycoma longifolia Jack (EL) in vivo. The blood-glucose-lowering activity of EL was studied in db/db mice administered crude powdered EL root (25, 50, and 100 mg/kg) orally for eight weeks. At the end of the study, HbA1c, insulin, plasma lipid levels, and histopathology were performed. Powdered EL root showed significant antihyperglycemic activity along with the control of body weight. After eight weeks of treatment, both the blood cholesterol level and the glycogen deposit in hepatocytes were remarkably lower, whereas the secreting insulin level was elevated. An improvement in islet performance was manifested as an increase in beta-cell number and pancreatic and duodenal homeobox 1 (PDX1) expression. Neogenesis or formation of new islets from pancreatic duct epithelial cells seen in the EL-treated group was encouraging. This study confirms the antihyperglycemic activity of EL through PDX1-associated beta-cell expansion resulting in an enhancement of islet performance.


Assuntos
Eurycoma/química , Proteínas de Homeodomínio/metabolismo , Hiperglicemia/tratamento farmacológico , Células Secretoras de Insulina/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Transativadores/metabolismo , Administração Oral , Animais , Contagem de Células , Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Hiperglicemia/fisiopatologia , Hipoglicemiantes , Células Secretoras de Insulina/fisiologia , Ilhotas Pancreáticas/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Fitoterapia , Extratos Vegetais/isolamento & purificação , Transativadores/genética
20.
Biochim Biophys Acta Mol Cell Res ; 1867(2): 118564, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31672612

RESUMO

Recently, histone deacetylase inhibitors (HDACi) have become widely used in anti-cancer treatment; however, due to acquired drug resistance and their relatively low specificity, they are largely ineffective against late-stage cancer. Thus, it is critical to elucidate the molecular mechanisms underlying these issues, so as to identify novel therapeutic targets to prevent late-stage cancer progression and resistance acquisition. The present study investigated the Aryl hydrocarbon receptor (AHR), that has been shown to mediate histone acetylation by regulating histone deacetylase (HDAC) activity during HDACi treatment in human gastric-cancer cell lines (i.e. AGS and NCI-N87 cells). The potent HDACi, Aza-PBHA, was thus shown to upregulate AHR expression in both AGS and NCI-N87 cell lines, and to increase histone acetylation levels by facilitating AHR/HDAC interactions. Conversely, AHR knockdown increased HDAC activity. Aza-PBHA also increased PKCα phosphorylation and membrane translocation; however, interestingly, PKCα inhibition reduced the Aza-PBHA-increased AHR and histone acetylation levels, and inhibited the formation of the AHR/HDAC complex, likely upregulating Aza-PBHA-inhibited cell migration. Thus, our results suggest that Aza-PBHA treatment increased AHR levels to suppress HDAC activity, and inhibited cell migration by activating PKCα activation. These findings support the use of drugs to control AHR-related epigenetic regulation as a promising potential method to prevent acquired resistance to cancer treatments.


Assuntos
Movimento Celular/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Proteína Quinase C-alfa/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Acetilação/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/química , Humanos , Fosforilação/efeitos dos fármacos , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Regulação para Cima/efeitos dos fármacos
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