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1.
J Immunol Res ; 2020: 9473497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32377540

RESUMO

C-type lectin domain family 5-member A (CLEC5A) associates with adaptor DAP12 (DNAX activation protein 12) to form receptor complexes involved in inflammatory responses. We postulated a potential role of CLEC5A in the pathogenesis of adult-onset Still's disease (AOSD) and aimed to investigate CLEC5A expression and its association with activity parameters and disease course. In 34 AOSD patients and 12 healthy controls (HC), circulating levels of CLEC5A-expressing monocytes or granulocytes were determined by flow cytometry analysis, the mRNA expression of CLEC5A and DAP12 on PBMCs by quantitative PCR, and plasma levels of proinflammatory cytokines by ELISA. AOSD patients had significantly higher percentages and mean fluorescence intensity (MFI) of CLEC5A-expressing monocytes (median 62.1% and 3.20, respectively) or granulocytes (72.6% and 3.22, respectively) compared with HC (in monocytes: 17.0% and 0.65, both p < 0.001; in granulocytes: 67.3%, p < 0.05 and 0.90, p < 0.001; respectively). Patients also had significantly higher levels of CLEC5A mRNA expression on PBMCs compared with HC (median 1.77 vs. 0.68, p < 0.05). The levels of CLEC5A-expressing monocytes or granulocytes were positively associated with activity scores and levels of IL-1ß and IL-18 in AOSD patients. The patients with a systemic pattern had significantly higher levels of CLEC5A-expressing granulocytes and IL-18 compared to those with a chronic articular pattern of disease course. After 6 months of therapy, levels of CLEC5A-expressing monocytes and granulocytes significantly declined, paralleling the decrease of AOSD activity. Elevated CLEC5A levels and their positive association with activity parameters suggest that CLEC5A is involved in the pathogenesis and may serve as an activity indicator of AOSD.

2.
Clin Rheumatol ; 39(6): 1945-1952, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31960208

RESUMO

OBJECTIVES: With galectin-3 playing an important role in inflammatory responses, elevated galectin-3 levels have been shown in patients with autoimmune diseases. However, there are limited data regarding galectin-3 expression in patients with autoinflammatory diseases such as adult-onset Still's disease (AOSD). This study aimed to investigate the extracellular galectin-3 expression and examine its association with activity parameters and disease outcome in AOSD patients. METHOD: Plasma levels of galectin-3 and inflammasome downstream cytokines including interleukin (IL)-1ß and IL-18 were determined by ELISA in 42 active AOSD patients and 20 healthy controls (HC). The protein levels of galectin-3 and cytokines were determined using immunoblotting. RESULTS: Plasma levels of galectin-3 and inflammasome downstream cytokines including IL-1ß and IL-18 were significantly higher in AOSD patients (median 5.02 ng/ml, interquartile range [IQR] 3.12-7.88 ng/ml; 3.42 pg/ml, IQR 1.48-6.70 pg/ml; and 5758 pg/ml, IQR 859-11,895 pg/ml, respectively) compared with HC (1.86 ng/ml, IQR 1.09-2.89 ng/ml; 0.99 pg/ml, IQR 0.62-1.35 pg/ml; and 129 pg/ml, IQR 71-155 pg/ml, respectively, all p < 0.001). Plasma galectin-3 levels were positively correlated with clinical activity scores, inflammatory parameters values, and the levels of IL-1ß and IL-18 in AOSD patients. AOSD patients with systemic pattern had significantly higher galectin-3 levels (median 6.08 ng/ml, IQR 4.01-9.54 ng/ml) compared with those with chronic articular pattern (3.56 ng/ml, IQR 3.04-4.98 ng/ml, p < 0.05). After 6-month therapy, galectin-3 levels significantly declined, paralleling the decreases in clinical activity scores and plasma levels of IL-1ß and IL-18. CONCLUSIONS: Elevated galectin-3 levels and their positive correlation with disease activity scores, inflammatory parameter, and inflammasome downstream cytokines suggest the involvement of galectin-3 in AOSD pathogenesis.Key Points• We revealed for the first time the association of plasma galectin-3 levels with AOSD activity parameters.• We explored the link between galectin-3 levels and NLRP3-inflammasome downstream cytokines in AOSD disease.

3.
Sci Rep ; 9(1): 15558, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664140

RESUMO

In this study, we sought to enhance the cutting properties of the various blades by coating them with Zr- and Fe-based thin film metallic glasses (TFMGs) to a thickness of 234-255 nm via sputter deposition. In oil-repellency/sliding tests on kitchen blades, the sliding angle and friction forces were as follows: bare blades (31.6°) and (35 µN), Ti-coated blades (20.3°) and (23.7 µN), and Z-TFMG coated blades (16.2°) and (19.2 µN). Comparisons were conducted with bare blades and those with a Teflon coating (a low-friction material commonly used for the coating of microtome blades). We also found that the Teflon coating reduced the cutting forces of an uncoated microtome blade by ~80%, whereas the proposed Z-TFMG achieved a ~51% reduction. The Z-TFMG presented no indications of delamination after being used 30 times for cutting; however, the Teflon coating proved highly susceptible to peeling and the bare blade was affected by surface staining. These results demonstrate the efficacy of the TFMG coating in terms of low friction, non-stick performance, and substrate adhesion. The performance of Z-TFMG and F-TFMG was also evaluated in split-thickness skin graft surgery using dermatome blades aimed at elucidating the influence of TFMG coatings on the healing of surgical incisions. When tested repeatedly on hairless skin, the surface roughness of uncoated blades increased by approximately 70%, whereas the surface roughness of TFMG-coated blades increases by only 8.6%. In the presence of hair, the surface roughness of uncoated blades increased by approximately ~108%, whereas the surface roughness of TFMG-coated blades increases by only ~23%. By Day 7, the wounds produced using TFMG-coated blades were noticeably smaller than those produced using uncoated blades, and these effects were particularly evident in hairy samples. This is a clear demonstration of the efficacy of TFMG surface coatings in preserving the cutting quality of surgical instruments.

4.
Int J Nanomedicine ; 14: 6539-6553, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496699

RESUMO

Aim: This paper reports on the incorporation of oleic acid (OA) within nanostructured lipid carriers (OA-NLC) to improve the anti-inflammatory effects in the presence of albumin. Materials and methods: NLCs produced via hot high-shear homogenization/ultrasonication were characterized in terms of particle size, zeta potential, and toxicity. We examined the effects of OA-NLC on neutrophil activities. Dermatologic therapeutic potential was also elucidated by using a murine model of leukotriene B4-induced skin inflammation. Results: In the presence of albumin, OA-NLC but not free OA inhibited superoxide generation and elastase release. Topical administration of OA-NLC alleviated neutrophil infiltration and severity of skin inflammation. Conclusion: OA incorporated within NLC can overcome the interference of albumin, which would undermine the anti-inflammatory effects of OA. OA-NLC has potential therapeutic effects in topical ointments.


Assuntos
Portadores de Fármacos/química , Inflamação/patologia , Lipídeos/química , Nanoestruturas/química , Neutrófilos/fisiologia , Ácido Oleico/química , Soroalbumina Bovina/farmacologia , Pele/patologia , Administração Tópica , Adulto , Animais , Cálcio/metabolismo , Bovinos , Morte Celular/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Humanos , Leucotrieno B4 , Lipídeos/toxicidade , Masculino , Camundongos Endogâmicos BALB C , Nanoestruturas/administração & dosagem , Nanoestruturas/toxicidade , Nanoestruturas/ultraestrutura , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Ácido Oleico/toxicidade , Elastase Pancreática/metabolismo , Superóxidos/metabolismo , Adulto Jovem
5.
Redox Biol ; 26: 101273, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31325723

RESUMO

Neutrophil infiltration plays a significant pathological role in inflammatory diseases. NADPH oxidase type 2 (NOX2) is a respiratory burst oxidase that generates large amounts of superoxide anion (O2•-) and subsequent other reactive oxygen species (ROS). NOX2 is an emerging therapeutic target for treating neutrophilic inflammatory diseases. Herein, we show that 4-[(4-(dimethylamino)butoxy)imino]-1-methyl-1H-benzo[f]indol-9(4H)-one (CYR5099) acts as a NOX2 inhibitor and exerts a protective effect against complete Freund's adjuvant (CFA)-induced inflammatory arthritis in mice. CYR5099 restricted the production of O2•- and ROS, but not the elastase release, in human neutrophils activated with various stimulators. The upstream signaling pathways of NOX2 were not inhibited by CYR5099. Significantly, CYR5099 inhibited NOX2 activity in activated human neutrophils and in reconstituted subcellular assays. In addition, CYR5099 reduced ROS production, neutrophil infiltration, and edema in CFA-induced arthritis in mice. Our findings suggest that CYR5099 is a NOX2 inhibitor and has therapeutic potential for treating neutrophil-dominant oxidative inflammatory disorders.


Assuntos
Artrite/metabolismo , Inibidores Enzimáticos/farmacologia , NADPH Oxidase 2/antagonistas & inibidores , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Artrite/tratamento farmacológico , Artrite/etiologia , Artrite/patologia , Biomarcadores , Cálcio/metabolismo , Células Endoteliais , Inibidores Enzimáticos/química , Espaço Extracelular/metabolismo , Adjuvante de Freund , Humanos , Masculino , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidase 2/química , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
6.
Opt Express ; 27(3): 1808-1815, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732228

RESUMO

An advanced laser headlight module (LHM) employing highly reliable glass phosphor is demonstrated. The novel glass-based YAG phosphor-converter layers fabricated by low-temperature of 750°C exhibited better thermal stability. The LHM consisted of a 5 × 1 blue laser diode array, an aspherical lens, a glass phosphor-converter layer with an aluminum thermal dissipation substrate, and a dichroic filter to allow pass blue light and reflect yellow phosphor light. The 5 × 1 blue laser array was packaged with five blue lasers having optical power of 1.2 W per laser. The LHM exhibited total output optical power of 6 W, luminous flux of 1860 lm, relative color temperature of 4100 K, and efficiency of more than 310 lm/W. The high-beam patterns of the LHMs were measured to be 45,000 luminous intensity (cd) at 0°, 31,000 cd at ± 2.5°, and 12,500 cd at ± 5°, which were well satisfied the ECE R112 class B regulation. The proposed high-performance LHM with highly reliable glass-based phosphor-converter layer fabricated by low temperature is favorable as one of the promising LHM candidates for use in the next-generation automobile headlight applications.

7.
Mol Neurobiol ; 56(1): 465-489, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29721855

RESUMO

Amyloid beta-peptide (Aß), the neurotoxic component of senile plaques in Alzheimer's disease (AD) brains, is known to trigger cell cycle reentry in post-mitotic neurons followed by apoptosis. However, the underlying mechanisms remain unclear. Recently, we have reported that Aßs stimulate the expression of inhibitor of differentiation-1 (Id1) to induce sonic hedgehog (SHH) (Hung et al., Mol Neurobiol 53(2):793-809, 2016), and both are mitogens capable of triggering cell cycle progression. In this work, we tested the hypothesis that Aß-induced Id1 and SHH contribute to cell cycle reentry leading to apoptosis in neurons. We found that Aß triggered cell cycle progression in the post-mitotic neurons, as indicated by the increased expression of two G1-phase markers including cyclin D1 and phosphorylated retinoblastoma protein (pRb), two G2-phase markers such as proliferating cell nuclear antigen (PCNA) and incorporation of 5-bromo-2'-deoxyuridine (BrdU) into newly synthesized DNA, as well as the mitotic marker histone H3 phosphorylated at Ser-10. As expected, Aß also enhanced caspase-3 cleavage in the cortical neurons. Id1 siRNA, the neutralization antibody against SHH (SHH-Ab), and the cyclin-dependent kinase (CDK)-4/6 inhibitor PD0332991 all attenuated, in part or in full, the Aß-induced expression of these cell cycle markers. Indeed, exogenous recombinant Id1 protein and the biologically active N-terminal fragment of SHH (SHH-N) were both sufficient to enhance the expression of cell cycle markers independent of Aß. Taken together, our results revealed the critical roles of Id1 and SHH mediating Aß-dependent cell cycle reentry and subsequently caspase-dependent apoptosis in the fully differentiated post-mitotic neurons, at least in vitro.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Apoptose/efeitos dos fármacos , Córtex Cerebral/patologia , Proteínas Hedgehog/metabolismo , Proteína 1 Inibidora de Diferenciação/metabolismo , Mitose/efeitos dos fármacos , Neurônios/patologia , Fragmentos de Peptídeos/toxicidade , Animais , Canabidiol/farmacologia , Caspase 3/metabolismo , Células Cultivadas , Humanos , Modelos Biológicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurotoxinas/toxicidade , Fosforilação/efeitos dos fármacos , Piperazinas/farmacologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , RNA Interferente Pequeno/metabolismo , Ratos Sprague-Dawley , Fase S/efeitos dos fármacos
8.
Cell Physiol Biochem ; 51(6): 2776-2793, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30562761

RESUMO

BACKGROUND/AIMS: Formyl peptide receptors (FPRs) recognize different endogenous and exogenous molecular stimuli and mediate neutrophil activation. Dysregulation of excessive neutrophil activation and the resulting immune responses can induce acute lung injury (ALI) in the host. Accordingly, one promising approach to the treatment of neutrophil-dominated inflammatory diseases involves therapeutic FPR1 inhibition. METHODS: We extracted a potent FPR1 antagonist from Garcinia multiflora Champ. (GMC). The inhibitory effects of GMC on superoxide anion release and elastase degranulation from activated human neutrophils were determined with spectrophotometric analysis. Reactive oxygen species (ROS) production and the FPR1 binding ability of neutrophils were assayed by flow cytometry. Signaling transduction mediated by GMC in response to chemoattractants was assessed with a calcium influx assay and western blotting. A lipopolysaccharide (LPS)-induced ALI mouse model was used to determine the therapeutic effects of GMC in vivo. RESULTS: GMC significantly reduced superoxide anion release, the reactive oxidants derived therefrom, and elastase degranulation mediated through selective, competitive FPR1 blocking in N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLF)-stimulated human neutrophils. In cell-free systems, GMC was unable to scavenge superoxide anions or suppress elastase activity. GMC produced a right shift in fMLF-activated concentration-response curves and was confirmed to be a competitive FPR1 antagonist. GMC binds to FPR1 not only in neutrophils, but also FPR1 in neutrophil-like THP-1 and hFPR1-transfected HEK293 cells. Furthermore, the mobilization of calcium and phosphorylation of mitogen-activated protein kinases and Akt, which are involved in FPR1-mediated downstream signaling, was competitively blocked by GMC. In an in vivo study, GMC significantly reduced pulmonary edema, neutrophil infiltration, and alveolar damage in LPS-induced ALI mice. CONCLUSION: Our findings demonstrate that GMC is a natural competitive FPR1 inhibitor, which makes it a possible anti-inflammatory treatment option for patients critically inflicted with FPR1-mediated neutrophilic lung damage.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Anti-Inflamatórios/uso terapêutico , Garcinia/química , Ativação de Neutrófilo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Receptores de Formil Peptídeo/antagonistas & inibidores , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/patologia , Animais , Anti-Inflamatórios/farmacologia , Linhagem Celular , Humanos , Camundongos Endogâmicos C57BL , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/patologia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Espécies Reativas de Oxigênio/imunologia , Receptores de Formil Peptídeo/imunologia , Superóxidos/imunologia
9.
Free Radic Biol Med ; 129: 372-382, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30312762

RESUMO

Critically ill patients have a high risk of sepsis. Various studies have demonstrated that propofol has anti-inflammatory effects that may benefit critically ill patients who require anesthesia. However, the mechanism and therapeutic effect remain incompletely understood. Our previous data suggest that propofol can act as a formyl peptide receptor 1 (FPR1) antagonist. Here, we hypothesize that propofol mitigates sepsis-induced acute lung injury (ALI) by inhibiting mitochondria-derived N-formyl peptide-mediated neutrophil activation. Oxidative stress caused by activated neutrophils is involved in the pathogenesis of ALI. In human neutrophils, propofol competitively reduced the release of superoxide and associated reactive oxygen species induced by fMMYALF, a human mitochondria-derived N-formyl peptide, suggesting that propofol effectively suppresses neutrophilic oxidative stress. In addition, propofol significantly inhibited fMMYALF-induced elastase release, chemotaxis, calcium mobilization, and phosphorylation of protein kinase B and mitogen-activated protein kinases. These results indicate that propofol suppresses neutrophil activation by blocking the interaction between endogenous N-formyl peptide and its receptor, FPR1, thus inhibiting downstream signaling. Furthermore, propofol alleviated alveolar wall disruption, edematous changes, and neutrophil infiltration in lipopolysaccharide-induced ALI in mice. Noticeably, propofol improved the survival of sepsis mice. This study indicates that the anti-neutrophil effects of propofol may benefit critically ill septic patients.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Propofol/farmacologia , Sepse/tratamento farmacológico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/mortalidade , Animais , Movimento Celular/efeitos dos fármacos , Fatores Quimiotáticos/farmacologia , Regulação da Expressão Gênica , Humanos , L-Lactato Desidrogenase/metabolismo , Elastase de Leucócito/genética , Elastase de Leucócito/metabolismo , Lipopolissacarídeos/administração & dosagem , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neutrófilos/imunologia , Neutrófilos/patologia , Oligopeptídeos/farmacologia , Peroxidase/genética , Peroxidase/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Receptores de Formil Peptídeo/genética , Receptores de Formil Peptídeo/metabolismo , Sepse/induzido quimicamente , Sepse/genética , Sepse/mortalidade , Transdução de Sinais , Análise de Sobrevida
10.
Biochem Pharmacol ; 154: 384-396, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29883707

RESUMO

Neutrophils play a significant role in inflammatory tissue injury. Activated neutrophils produce reactive oxygen species (ROS), release proteases, and form neutrophil extracellular traps (NETs), significantly affecting the pathogenesis of inflammatory arthritis. We examined the therapeutic effects of luteolin, a flavone found in many plants, in neutrophilic inflammation and on acute inflammatory arthritis. Luteolin significantly inhibited superoxide anion generation, ROS production, and NET formation in human neutrophils. The increase in elastase release, CD11b expression, and chemotaxis was also inhibited by luteolin. Luteolin significantly suppressed phosphorylation of extracellular signal-regulated kinase (Erk) and mitogen-activated protein kinase kinase-1 (MEK-1), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Analysis of the molecular mechanism further revealed that luteolin acts as a Raf-1 inhibitor. In mice with complete Freund's adjuvant-induced arthritis, luteolin ameliorated neutrophil infiltration as well as the thickness of paw edema and ROS production. In conclusion, in addition to its known ROS scavenging effect, this study is the first to provide evidence that luteolin diminishes human neutrophil inflammatory responses by inhibiting Raf1-MEK-1-Erk. Our results focused on the importance of neutrophil activation in inflammatory tissue injury and offer opportunities for the development of luteolin's therapeutic potential to attenuate neutrophilic inflammatory diseases.


Assuntos
Artrite/metabolismo , Luteolina/uso terapêutico , Ativação de Neutrófilo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-raf/metabolismo , Animais , Artrite/tratamento farmacológico , Células Cultivadas , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Edema/metabolismo , Humanos , Luteolina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ativação de Neutrófilo/fisiologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Estresse Oxidativo/fisiologia
11.
Exp Ther Med ; 14(5): 4853-4861, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29201190

RESUMO

A previous study by our group showed that a 44-amino-acid fragment of pigment epithelium-derived factor (PEDF) facilitated corneal epithelial wound healing. In the present study this fragment was shortened to obtain peptides of 18, 20 and 29 amino acids in length, and their promoting effects on the healing of full-thickness skin wounds were assessed. Peptides were delivered periodically by topical application to punch wounds of mice. The wound healing speed was evaluated by measuring the reduction of wound areas at 4 and 7 days after injury. Histological analysis with Masson's trichrome staining was used to confirm epithelialization and dermal collagen deposition. Proliferation of epithelial basal cells was documented by 5-bromo-2'-deoxyuridine incorporation. Hair follicle stem cells were identified by immunostaining for leucine-rich repeat-containing G protein-coupled receptor 6. The results indicated that the 20- and 29-amino-acid short peptides significantly reduced the time required for wound healing compared to the vehicle. Histological analysis confirmed faster epithelial cell coverage of open wounds. Treatment with the PEDF peptide fragments also contributed to granulation, tissue formation by increasing the fibroblast population and enhancing collagen deposition in the dermis. Wounds treated with PEDF peptide fragments contained more basal cells proliferated in the epithelium. Moreover, hair follicle stem cells were also stimulated to proliferate by peptide exposure. In conclusion, the present study reported the identification of two short peptides that can enhance the healing of full-thickness skin wounds following topical application. The underlying mechanisms may involve activation of basal cell proliferation and mobilization of hair follicle stem cells.

12.
Sci Rep ; 7(1): 6718, 2017 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-28751674

RESUMO

Formyl peptide receptor 1 (FPR1) mediates bacterial and mitochondrial N-formyl peptides-induced neutrophil activation. Therefore, FPR1 is an important therapeutic target for drugs to treat septic or sterile inflammatory diseases. Honokiol, a major bioactive compound of Magnoliaceae plants, possesses several anti-inflammatory activities. Here, we show that honokiol exhibits an inhibitory effect on FPR1 binding in human neutrophils. Honokiol inhibited superoxide anion generation, reactive oxygen species formation, and elastase release in bacterial or mitochondrial N-formyl peptides (FPR1 agonists)-activated human neutrophils. Adhesion of FPR1-induced human neutrophils to cerebral endothelial cells was also reduced by honokiol. The receptor-binding results revealed that honokiol repressed FPR1-specific ligand N-formyl-Nle-Leu-Phe-Nle-Tyr-Lys-fluorescein binding to FPR1 in human neutrophils, neutrophil-like THP-1 cells, and hFPR1-transfected HEK293 cells. However, honokiol did not inhibit FPR2-specific ligand binding to FPR2 in human neutrophils. Furthermore, honokiol inhibited FPR1 agonist-induced calcium mobilization as well as phosphorylation of p38 MAPK, ERK, and JNK in human neutrophils. In conclusion, our data demonstrate that honokiol may have therapeutic potential for treating FPR1-mediated inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Compostos de Bifenilo/farmacologia , Células Endoteliais/efeitos dos fármacos , Lignanas/farmacologia , Neutrófilos/efeitos dos fármacos , Oligopeptídeos/antagonistas & inibidores , Receptores de Formil Peptídeo/genética , Animais , Anti-Inflamatórios/isolamento & purificação , Compostos de Bifenilo/isolamento & purificação , Encéfalo/citologia , Encéfalo/metabolismo , Adesão Celular/efeitos dos fármacos , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Lignanas/isolamento & purificação , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/imunologia , Magnolia/química , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/citologia , Neutrófilos/imunologia , Oligopeptídeos/farmacologia , Extratos Vegetais/química , Receptores de Formil Peptídeo/antagonistas & inibidores , Receptores de Formil Peptídeo/imunologia , Receptores de Lipoxinas/genética , Receptores de Lipoxinas/imunologia , Células THP-1 , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
13.
Free Radic Biol Med ; 106: 379-392, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28263828

RESUMO

Over-activated neutrophils produce enormous oxidative stress and play a key role in the development of acute and chronic inflammatory diseases. 6-Hydroxy-5,7-dimethoxy-flavone (UFM24), a flavone isolated from the Annonaceae Uvaria flexuosa, showed inhibitory effects on human neutrophil activation and salutary effects on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. UFM24 potently inhibited superoxide anion (O2•-) generation, reactive oxidants, and CD11b expression, but not elastase release, in N-formyl-l-methionyl-l-leucyl-l-phenylalanine (fMLF)-activated human neutrophils. However, UFM24 failed to scavenge O2•- and inhibit the activity of subcellular NADPH oxidase. fMLF-induced phosphorylation of protein kinase B (Akt) was inhibited by UFM24. Noticeably, UFM24 increased cyclic adenosine monophosphate (cAMP) concentration and protein kinase (PK) A activity in activated human neutrophils. PKA inhibitors significantly reversed the inhibitory effects of UFM24, suggesting that the effects of UFM24 were through cAMP/PKA-dependent inhibition of Akt activation. Additionally, activity of cAMP-related phosphodiesterase (PDE)4, but not PDE3 or PDE7, was significantly reduced by UFM24. Furthermore, UFM24 attenuated neutrophil infiltration, myeloperoxidase activity, and pulmonary edema in LPS-induced ALI in mice. In conclusion, our data demonstrated that UFM24 inhibits oxidative burst in human neutrophils through inhibition of PDE4 activity. UFM24 also exhibited significant protection against endotoxin-induced ALI in mice. UFM24 has potential as an anti-inflammatory agent for treating neutrophilic lung damage.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Antígeno CD11b/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Flavonas/administração & dosagem , Ativação de Neutrófilo/efeitos dos fármacos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Animais , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Lipopolissacarídeos/toxicidade , Camundongos , N-Formilmetionina Leucil-Fenilalanina/administração & dosagem , NADPH Oxidases/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Inibidores da Fosfodiesterase 4/administração & dosagem , Explosão Respiratória/efeitos dos fármacos , Superóxidos/metabolismo
14.
Free Radic Biol Med ; 106: 254-269, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28232203

RESUMO

Formyl peptide receptor 1 (FPR1) is an emerging therapeutic target for the discovery of drugs to treat neutrophilic inflammatory diseases. However, development of FPR1 antagonists for clinical use is still inadequate. The purpose of this study was to identify a synthetic dipeptide N-(N-benzoyl-L-tryptophanyl)-D-phenylanlanine methyl ester (HCH6-1) as a FPR1 inhibitor and to investigate its protective effects against acute lung injury (ALI). HCH6-1 inhibited superoxide anion generation, elastase release, and chemotaxis in human neutrophils specifically activated by formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLF), an FPR1 agonist. HCH6-1 produced right shifts in the concentration-response curves of fMLF, suggesting that HCH6-1 was a competitive antagonist of FPR1. Indeed, HCH6-1 bound to FPR1 in human neutrophils and neutrophil-like THP-1 as well as hFPR1-transfected HEK293 cells. Also, the FPR1 downstream signaling pathways were competitively inhibited by HCH6-1. Furthermore, HCH6-1 prevented pulmonary neutrophil infiltration and edema along with alveolar damage in LPS-induced ALI in mice. Our findings suggest that HCH6-1, a FPR1 antagonist, may have potential as a new therapeutic agent for treating FPR1-involved inflammatory lung diseases.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Dipeptídeos/administração & dosagem , Ativação de Neutrófilo/efeitos dos fármacos , Receptores de Formil Peptídeo/genética , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Animais , Quimiotaxia/efeitos dos fármacos , Dipeptídeos/síntese química , Modelos Animais de Doenças , Células HEK293 , Humanos , Lipopolissacarídeos/toxicidade , Camundongos , Ativação de Neutrófilo/genética , Infiltração de Neutrófilos/efeitos dos fármacos , Receptores de Formil Peptídeo/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Superóxidos/metabolismo
15.
Mol Neurobiol ; 53(2): 793-809, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25502463

RESUMO

One major pathological hallmark of Alzheimer's disease (AD) is the accumulation of senile plaques mainly composed of neurotoxic amyloid beta-peptide (Aß) in the patients' brains. Sonic hedgehog (SHH) is a morphogen critically involved in the embryonic development of the central nervous system (CNS). In the present study, we tested whether Aß may induce SHH expression and explored its underlying mechanisms. We found that both Aß25-35 and Aß1-42 enhanced SHH expression in the primary cortical neurons derived from fetal rat brains. Immunohistochemistry revealed heightened expression of SHH in the cortex and hippocampus of aged (9 and 12 months old) AD transgenic mouse brains as compared to age-matched littermate controls. Chromatin immunoprecipitation (ChIP) assay demonstrated that Aß25-35 enhanced binding of hypoxia-inducible factor-1 (HIF-1) to the promoter of the Shh gene in primary cortical cultures; consistently, Aß25-35 induction of SHH was abolished by HIF-1α small interfering RNA (siRNA). Aß25-35 also time-dependently induced inhibitor of differentiation-1 (Id1) that has been shown to stabilize HIF-1α; further, Aß25-35-mediated induction of HIF-1α and SHH was both suppressed by Id1 siRNA. Pharmacological induction of HIF-1α by cobalt chloride and application of the cell-permeable recombinant Id1 proteins were both sufficient to induce SHH expression. Finally, both the SHH pathway inhibitor cyclopamine and its neutralizing antibody attenuated Aß cytotoxicity, albeit to a minor extent. These results thus established a signaling cascade of "Aß â†’ Id1 → HIF-1 → SHH" in primary rat cortical cultures; furthermore, SHH may in part contribute to Aß neurotoxicity.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Córtex Cerebral/citologia , Proteínas Hedgehog/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteína 1 Inibidora de Diferenciação/metabolismo , Neurônios/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Ratos Sprague-Dawley
16.
J Biomater Sci Polym Ed ; 26(13): 855-67, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26155720

RESUMO

A tri-layered chitosan-based scaffold was successfully made to replicate the striation of a full-thickness skin more accurately than a single- or bi-layered scaffold, which needed weeks of co-culturing of fibroblasts and keratinocytes to achieve similar striation. Chitosan solution was freeze-dried and made into porous disks. Chitosan or chitosan-pectin in acetic acid solution was electrospun onto the chitosan disk to form a nanofibrous layer and a thin film. Examinations based on scanning electron spectroscopy showed that the scaffold was composed of a porous layer (2 mm) to simulate the dermis, a thin film (25-45 µm) to mimic the basement membrane, and a layer of nanofibers (100-200 µm) to serve as the protective epidermis. The tensile strength and modulus of the composite scaffold were significantly higher than those of the chitosan disk (p < 0.01). The composite was able to quickly absorb water and stayed intact throughout the course of the 14-day cell culture tests. The fibroblast cells seeded on both sides of the scaffolds were able to proliferate and stayed separated by the thin film.


Assuntos
Quitosana , Pele Artificial , Tecidos Suporte , Ácido Acético , Linhagem Celular , Proliferação de Células , DNA/metabolismo , Módulo de Elasticidade , Fibroblastos/fisiologia , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanofibras , Pectinas , Porosidade , Espectrometria de Fluorescência , Estresse Mecânico , Resistência à Tração , Água
17.
Biomed Mater ; 10(3): 035004, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25970802

RESUMO

A 3D plotting system was used to make chitosan-based tissue scaffolds with interconnected pores using pure chitosan (C) and chitosan cross-linked with pectin (CP) and genipin (CG). A freeze-dried chitosan scaffold (CF/D) was made to compare with C, to observe the effects of structural differences. The fiber size, pore size, porosity, compression strength, swelling ratio, drug release efficacy, and cumulative weight loss of the scaffolds were measured. Osteoblasts were cultured on the scaffolds and their proliferation, type I collagen production, alkaline phosphatase activity, calcium deposition, and morphology were observed. C had a lower swelling ratio, degradation, porosity and drug release efficacy and a higher compressional stiffness and cell proliferation compared to CF/D (p < 0.05). Of the 3D-plotted samples, cells on CP exhibited the highest degree of mineralization after 21 d (p < 0.05). CP also had the highest swelling ratio and fastest drug release, followed by C and CG (p < 0.05). Both CP and CG were stiffer and degraded more slowly in saline solution than C (p < 0.05). In summary, 3D-plotted scaffolds were stronger, less likely to degrade and better promoted osteoblast cell proliferation in vitro compared to the freeze-dried scaffolds. C, CP and CG were structurally similar, and the different crosslinking caused significant changes in their physical and biological performances.


Assuntos
Substitutos Ósseos/química , Quitosana/química , Osteoblastos/citologia , Osteoblastos/metabolismo , Tecidos Suporte/química , Fosfatase Alcalina/metabolismo , Animais , Materiais Biocompatíveis/química , Calcificação Fisiológica , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Colágeno Tipo I/biossíntese , Hidrogéis , Iridoides/química , Teste de Materiais , Camundongos , Microscopia Eletrônica de Varredura , Pectinas/química , Porosidade , Impressão Tridimensional , Engenharia Tecidual
18.
Biochim Biophys Acta ; 1853(10 Pt A): 2306-25, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25986861

RESUMO

Oncostatin M (OSM), a cytokine in the interleukin-6 (IL-6) family, has been proposed to play a protective role in the central nervous system, such as attenuation of excitotoxicity induced by N-methyl-D-aspartate (NMDA) and glutamate. However, the potential neuroprotective effects of OSM against mitochondrial dysfunction have never been reported. In the present study, we tested the hypothesis that OSM may confer neuronal resistance against 3-nitropropionic acid (3-NP), a plant toxin that irreversibly inhibits the complex II of the mitochondrial electron transport chain, and characterized the underlying molecular mechanisms. We found that OSM preconditioning dose- and time-dependently protected cortical neurons against 3-NP toxicity. OSM stimulated expression of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic Bcl-2 family member expressed in differentiating myeloid cells, that required prior phosphorylation of Janus kinase-1 (JAK1), JAK2, extracellular signal-regulated kinase-1/2 (ERK1/2), signal transducer and activator of transcription-3 (STAT3), STAT1, and cAMP-response element-binding protein (CREB). Pharmacological inhibitors of JAK1, JAK2, ERK1/2, STAT3, STAT1, and CREB as well as the siRNA targeting at STAT3 and Mcl-1 all abolished OSM-dependent 3-NP resistance. Finally, OSM-dependent Mcl-1 induction contributed to the enhancements of mitochondrial bioenergetics including increases in spare respiratory capacity and ATP production. In conclusion, our findings indicated that OSM induces Mcl-1 expression via activation of ERK1/2, JAK1/2, STAT1/3, and CREB; furthermore, OSM-mediated Mcl-1 induction contributes to bioenergetic improvements and neuroprotective effects against 3-NP toxicity in cortical neurons. OSM may thus serve as a novel neuroprotective agent against mitochondrial dysfunction commonly associated with pathogenic mechanisms underlying neurodegeneration.


Assuntos
Córtex Cerebral/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Metabolismo Energético/fisiologia , Janus Quinase 1/metabolismo , Janus Quinase 2/metabolismo , Mitocôndrias/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neurônios/metabolismo , Oncostatina M/metabolismo , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/farmacologia , Córtex Cerebral/citologia , Metabolismo Energético/efeitos dos fármacos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Neurônios/citologia , Nitrocompostos/efeitos adversos , Nitrocompostos/farmacologia , Propionatos/efeitos adversos , Propionatos/farmacologia , Ratos
19.
Chemphyschem ; 16(4): 812-6, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25572260

RESUMO

ZnO is a defect-governed oxide and emits light at both visible and UV regimes. This work employs atomic layer deposition to produce oxide particles on oxygenated carbon nanotubes, and the composites only show emission profiles at short wavelengths. The quenching of defect-related emissions at long wavelengths is verified, owing to carboxyl diffusion into oxygen vacancies, and doping is supported by ZnCO3 formation in oxide lattice. Fully coated tubes display an increased photocurrent and the quantum efficiency increases by 22 % relative to the bare nanotubes.

20.
Vet Parasitol ; 205(3-4): 540-50, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25269988

RESUMO

Anisakid nematodes are distributed worldwide in a wide variety of marine fishes and they are known to cause the zoonotic disease, anisakiasis. The temperature control is commonly applied for prevention and control of anisakiasis. To analyze the cellular response to temperature stress in Anisakis, the heat shock protein 90 (Hsp90) was chosen in the present study, as it plays a key role in many cellular processes and responds to stress conditions such as heat or cold shock. Anisakids were sampled from spotted mackerel Scomber australasicus caught from the coastal waters of Yilan, in northeastern Taiwan (25 °N, 121 °E). Anisakid nematodes were pre-identified morphologically and later molecularly by PCR-RFLP. In total, we obtained six species of the genus Anisakis, A. typica, A. pegreffii, A. paggiae, A. brevispiculata, A. physeteris, and a recombinant genotype between A. pegreffii and A. simplex sensu stricto. Thereby we provide new host and locality records for A. paggiae, A. brevispiculata and A. physeteris. The Hsp90 genes of five species (except the recombinant genotype) were cloned by rapid amplification of cDNA ends (RACE) and their deduced amino acid sequences were further characterized. Quantitative real-time PCR and Western blot analysis were used to examine the expression levels of the Hsp90 in A. pegreffii under different temperature conditions. Quantitative RT-PCR showed that Hsp90 transcript levels increased slightly under heat shock (50 °C) treatment, and increased gradually during the first 3h, and thereafter, returned to its baseline value at 37 °C. Under cold shock (4 °C) treatment, the mRNA expression of Hsp90 did not change significantly. In addition, we found a clear time-dependent Hsp90 protein expression pattern of A. pegreffii exposed to high temperature. Our results suggest that the mRNA and protein expression patterns of Hsp90 are related to the temperature, and are especially significantly increased under heat stress.


Assuntos
Anisaquíase/veterinária , Anisakis/isolamento & purificação , Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Animais , Anisaquíase/parasitologia , Anisakis/classificação , Anisakis/genética , DNA Espaçador Ribossômico/genética , Proteínas de Choque Térmico/genética , Larva , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Especificidade da Espécie , Taiwan , Temperatura
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