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1.
Small ; : e2310409, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477694

RESUMO

Electrochemical nitrite reduction reaction ( NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^{\mathrm{ - }}{\mathrm{RR}}$ ), as a green and sustainable ammonia synthesis technology, has broad application prospects and environmental friendliness. Herein, an unconventional p-d orbital hybridization strategy is reported to realize the fabrication of defect-rich CuSb porous nanonetwork (CuSb PNs) electrocatalyst for NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^ - {\mathrm{RR}}$ . The crystalline/amorphous heterophase structure is cleverly introduced into the porous nanonetworks, and this defect-rich structure exposes more atoms and activated boundaries. CuSb PNs exhibit a large NH3 yield ( r N H 3 ${{r}_{{\mathrm{N}}{{{\mathrm{H}}}_{\mathrm{3}}}}}$ ) of 946.1 µg h-1 m cat - 1 ${\mathrm{m}}_{{\mathrm{cat}}}^{ - {\mathrm{1}}}$ and a high faradaic efficiency (FE) of 90.7%. Experimental and theoretical studies indicate that the excellent performance of CuSb PNs results from the defect-rich porous nanonetworks structure and the p-d hybridization of Cu and Sb elements. This work describes a powerful pathway for the fabrication of p-d orbital hybrid defect-rich porous nanonetworks catalysts, and provides hope for solving the problem of nitrogen oxide pollution in the field of environment and energy.

2.
Pharm Biol ; 61(1): 1431-1445, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37674371

RESUMO

CONTEXT: Duhuo Jisheng pill (DHJS) is a classic traditional Chinese medicine (TCM) formula for rheumatoid arthritis (RA). The effective components and therapeutic mechanisms of DHJS for treating RA are still unclear. OBJECTIVE: To explore the potential mechanism of DHJS against RA by means of network pharmacology and experimental verification. MATERIALS AND METHODS: A network pharmacology and molecular docking analysis based on phytochemistry was used to elucidate the mechanism of DHJS against RA. The targets of DHJS anti-RA active ingredient were obtained by searching TCMSP, ETCM and TCMSID. The RA model induced by collagen was established in Wistar rats. The rats in the DHJS group were administered doses of 0.5, 1.0 and 2.0 g/kg for a period of 10 d. The expression of targets was measured with Western blot. RESULTS: Network pharmacology analysis showed that the anti-RA effect of DHJS was mediated by targets involved in immunity, inflammation and apoptosis, as well as PI3K-Akt and NF-κB signalling pathways. Of 2.0 g/kg DHJS significantly alleviated the ankle inflammation (IL-6: 62.73 ± 8.39 pg/mL, IL-1ß: 50.49 ± 11.47 pg/mL, TNF-α: 16.88 ± 3.05 pg/mL, IL-17A: 12.55 ± 1.87 pg/mL, IL-10: 16.24 ± 3.00 pg/mL), comparing with the model group (IL-6: 92.02 ± 13.25 pg/mL, IL-1ß: 71.85 ± 4.12 pg/mL, TNF-α: 25.64 ± 3.69 pg/mL, IL-17A: 22.14 ± 4.56 pg/mL, IL-10: 9.51 ± 3.03 pg/mL) (p < 0.05). Moreover, the protein expression of p-PI3K, p-AKT and p-p65 significantly decreased after DHJS administration. CONCLUSIONS: DHJS could alleviate the collagen-induced arthritis (CIA) by the PI3K/AKT/NF-κB signalling pathway.


Assuntos
Artrite Reumatoide , NF-kappa B , Animais , Ratos , Ratos Wistar , Simulação de Acoplamento Molecular , Interleucina-10 , Interleucina-17 , Interleucina-6 , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fator de Necrose Tumoral alfa , Artrite Reumatoide/tratamento farmacológico , Inflamação
3.
J Environ Manage ; 232: 574-583, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30508777

RESUMO

The ecological stormwater processes of a sponge city include the ecological processes of runoff and confluence, the thermal landscape and decontamination. In this study, elements of stormwater processes - short-duration heavy rainfall, rainstorm intensity, drainage networks, surface temperature, the scouring process and the cumulative process of pollutants (SS, COD, TP and NH3_N), and, finally, the low impact development (LID) facilities at different recurrence periods-are simulated using the rainstorm intensity model, the scoured exponential model and the split-window algorithm. Land-use types and LID facilities in sponge cities greatly influence the spatial distribution of ecological stormwater processes. Rainstorm intensity, cumulative volume, flow rate and drainage capacity all increase in the initial stage of rainfall and decrease in the later stage, with an increase in rainfall duration. Rainfall, infiltration amount, runoff and rainstorm intensity all increase; however, the runoff coefficient and infiltration proportion decrease with an increase in the rainfall recurrence period. LID facilities can increase rainfall, peak flood delay time, area of low temperature zone, annual runoff control rate and runoff pollutant reduction rate at the recurrence periods of 1 a, 3 a, 5 a, 10 a, 20 a, 30 a and 50 a, especially during short-duration rainfall. The paper concludes LID facilities of sponge cities play an important role in weakening the effects of rain-, heat- and pollution-islands.


Assuntos
Monitoramento Ambiental , Movimentos da Água , China , Cidades , Ilhas , Chuva
4.
Molecules ; 22(12)2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29189741

RESUMO

As a TCM, Hedyotis diffusa Willd. has been using to treat malignant tumors, and many studies also showed that the extracts from Hedyotis diffusa Willd. possessed evident antitumor activities. Therefore, we carried out chemical study on Hedyotis diffusa Willd. and investigated the cytotoxicity of the obtained compounds on a panel of eight tumor cell lines. As a result, four new compounds were isolated from Hedyotis diffusa Willd., including three iridoid glycosides of Shecaoiridoidside A-C (1-3) and a cerebroside of shecaocerenoside A (4). Also, six known iridoid compounds (5-10) were also obtained. The cytotoxicity of all compounds against human tumor cell lines of HL-60, HeLa, HCT15, A459, HepG2, PC-3, CNE-2, and BCG-823 were also evaluated in vitro. New compound 3 exhibited evident cytotoxicity to all tumor cell lines except the Hela, and the IC50 values are from 9.6 µM to 62.2 µM, while new compound 4 showed moderate cytotoxicity to all the cell lines, and the IC50 values are from 33.6 µM to 89.3 µM. By contrast, new compound 1 and known compound 9 showed moderate cytotoxicity to HCT15, A459, and HepG2 selectively. Known compound 7 also exhibited moderate cytotoxicity to HCT15 and A459 selectively.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Hedyotis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Hidrólise , Glicosídeos Iridoides/química , Glicosídeos Iridoides/farmacologia , Iridoides/química , Iridoides/farmacologia , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética
5.
Biochem Biophys Res Commun ; 447(1): 158-64, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24704453

RESUMO

Fbx4 is a specific substrate recognition component of SCF ubiquitin ligases that catalyzes the ubiquitination and subsequent degradation of cyclin D1 and Trx1. Two isoforms of human Fbx4 protein, the full length Fbx4α and the C-terminal truncated Fbx4ß have been identified, but their functions remain elusive. In this study, we demonstrated that the mRNA level of Fbx4 was significantly lower in hepatocellular carcinoma tissues than that in the corresponding non-tumor tissues. More importantly, we identified three novel splicing variants of Fbx4: Fbx4γ (missing 168-245 nt of exon1), Fbx4δ (missing exon6) and a N-terminal reading frame shift variant (missing exon2). Using cloning sequencing and RT-PCR, we demonstrated these novel splice variants are much more abundant in human cancer tissues and cell lines than that in normal tissues. When expressed in Sk-Hep1 and NIH3T3 cell lines, Fbx4ß, Fbx4γ and Fbx4δ could promote cell proliferation and migration in vitro. Concordantly, these isoforms could disrupt cyclin D1 degradation and therefore increase cyclin D1 expression. Moreover, unlike the full-length isoform Fbx4α that mainly exists in cytoplasm, Fbx4ß, Fbx4γ, and Fbx4δ locate in both cytoplasm and nucleus. Since cyclin D1 degradation takes place in cytoplasm, the nuclear distribution of these Fbx4 isoforms may not be involved in the down-regulation of cytoplasmic cyclin D1. These results define the impact of alternative splicing on Fbx4 function, and suggest that the attenuated cyclin D1 degradation by these novel Fbx4 isoforms provides a new insight for aberrant cyclin D1 expression in human cancers.


Assuntos
Carcinoma Hepatocelular/metabolismo , Ciclina D1/metabolismo , Proteínas F-Box/genética , Proteínas F-Box/fisiologia , Neoplasias Hepáticas/metabolismo , Processamento Alternativo , Animais , Carcinoma Hepatocelular/química , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Regulação para Baixo , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/química , Camundongos , Células NIH 3T3 , Isoformas de Proteínas/fisiologia , Proteólise
6.
Chem Pharm Bull (Tokyo) ; 62(12): 1173-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25450625

RESUMO

The liquid self-emulsifying drug delivery system (L-SEDDS), commonly used to deliver effective but poorly water-soluble oleanolic acid (OA), has many limitations such as high manufacturing costs, few choices of dosage forms, risk of leakage from hard gelatin capsules, low stability, limited portability, incompatibility with capsule materials, and relatively restricted storage conditions. Thus the main purpose of our study was to develop a promising solid lipid-based drug delivery system (S-SEDDS) for OA. The S-SEDDS, prepared from wet granulation with an optimized L-SEDDS formulation and mannitol, was characterized by particle size analysis, scanning electron microscopy, differential scanning calorimetry, and X-ray powder diffraction. Finally, the solubility of the OA-loaded S-SEDDS was compared with that of OA powder in the dissolution assay. Our new S-SEDDS for OA was developed from the optimum L-SEDDS with ethyl oleate (oil phase), Labrasol (surfactant), and Transcutol P (cosurfactant) at a volume ratio of 15:71:14 with 1.5% w/v OA and mannitol. The dissolution of OA was improved by 60% compared with that of the pure OA powder. All the problems associated with the L-SEDDS were resolved. The methodologies we developed for OA delivery could also be utilized for the delivery of other drugs with the S-SEDDS.


Assuntos
Química Farmacêutica , Sistemas de Liberação de Medicamentos , Lipídeos/química , Formas de Dosagem , Composição de Medicamentos , Etilenoglicóis/química , Excipientes , Glicerídeos , Técnicas In Vitro , Manitol , Ácido Oleanólico/química , Compostos Orgânicos/química , Tamanho da Partícula , Pós , Solubilidade , Tensoativos
7.
ACS Omega ; 6(24): 15940-15947, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34179638

RESUMO

Lignocellulosic biorefineries have received considerable attention for the purpose of producing high-value chemicals and materials. Levulinic acid (LA) is an important biomass-derived platform chemical that is produced from sugar-based biomass. Unfortunately, the catalysts reported thus far have shortcomings, such as expensive starting materials, complicated synthesis or purification operations, and a low LA yield under harsh reaction conditions. Herein, we develop a novel dual-functional catalyst, HScCl4, by combining Brønsted acid (HCl) and Lewis acid (ScCl3) sites. The as-prepared HScCl4 catalyst shows high efficiency and high selectivity for converting 5-hydroxymethylfurfural (HMF) to LA in a biphasic system consisting of methyl isobutyl ketone (MIBK) and water. The density functional theory (DFT) results show that the synergistic catalytic effect, originating from the Brønsted and Lewis acidic sites of HScCl4, significantly decreases the energy barriers of reactants and intermediates, thus facilitating the conversion of HMF to LA. Moreover, the efficient separation of LA in the water-MIBK biphasic system by extracting LA to the MIBK phase minimizes the side reactions of LA and thus the formation of humins while significantly improving the LA yield. The conversion of HMF and the selectivity for LA are 100 and 95.6% at 120 °C for 35 min, respectively. The free energy (ΔG) and activation energy (E a) of the reaction are -30 kcal mol-1 and 13.7 kJ mol-1, respectively. The developed process provides a green, sustainable, and efficient pathway to produce LA from biomass-derived HMF under mild conditions.

8.
Zhongguo Zhong Yao Za Zhi ; 35(3): 393-6, 2010 Feb.
Artigo em Zh | MEDLINE | ID: mdl-20423014

RESUMO

The clinical or experimental study proves that Chinese medicine such as Tripteryglum wilfordii, Lignum Sappan, Caulis Sinomenii, Radix Trichosanthis and Herba Artemisiae Annuae have good immunosuppressive activity. Further researches on the immunosuppressive active components from Chinese medicine have been the main direction in recent years. The recent researches on immunosuppressive effect and possible mechanisms for the monomers such as triperine, triptolide, bazilein, potosappanin A, sinomenine, trichosanthin and artemisinin extracted from those Chinese medicine are introduced in this review.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Animais , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Compostos de Epóxi/farmacologia , Compostos de Epóxi/uso terapêutico , Humanos , Morfinanos/farmacologia , Morfinanos/uso terapêutico , Fenantrenos/farmacologia , Fenantrenos/uso terapêutico , Plantas Medicinais/química , Tricosantina/farmacologia , Tricosantina/uso terapêutico
9.
Int Immunopharmacol ; 80: 106210, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31972425

RESUMO

The JAK/STAT signaling pathway is an universally expressed intracellular signal transduction pathway and involved in many crucial biological processes, including cell proliferation, differentiation, apoptosis, and immune regulation. It provides a direct mechanism for extracellular factors-regulated gene expression. Current researches on this pathway have been focusing on the inflammatory and neoplastic diseases and related drug. The mechanism of JAK/STAT signaling is relatively simple. However, the biological consequences of the pathway are complicated due to its crosstalk with other signaling pathways. In addition, there is increasing evidence indicates that the persistent activation of JAK/STAT signaling pathway is closely related to many immune and inflammatory diseases, yet the specific mechanism remains unclear. Therefore, it is necessary to study the detailed mechanisms of JAK/STAT signaling in disease formation to provide critical reference for clinical treatments of the diseases. In this review, we focus on the structure of JAKs and STATs, the JAK/STAT signaling pathway and its negative regulators, the associated diseases, and the JAK inhibitors for the clinical therapy.


Assuntos
Doenças do Sistema Imunitário/tratamento farmacológico , Inflamação/tratamento farmacológico , Janus Quinases/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/imunologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Doenças do Sistema Imunitário/imunologia , Doenças do Sistema Imunitário/patologia , Inflamação/imunologia , Inflamação/patologia , Janus Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Fatores de Transcrição STAT/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
10.
Zhongguo Zhong Yao Za Zhi ; 33(13): 1519-23, 2008 Jul.
Artigo em Zh | MEDLINE | ID: mdl-18837304

RESUMO

OBJECTIVE: To investigate the effects of nitrogen forms on the camptothecin (CPT) content, tryptophan synthase (TSB) and tryptophan decarboxylase (TDC) activities in Camptotheca acuminata seedlings. METHOD: The seedlings of C. acuminata with 6 pairs of leaves were subjected to 5 different NH4(+) -N/NO3(-) -N ratio (0 : 100, 75 : 25, 50 : 50, 25 : 75, 100 : 0) treatments by sand culture in a greenhouse. The CPT content, TSB activity in the young leaves and TDC in the stem barks of the seedlings were determined by HPLC on the 15th, 30th, 45th, 60th and 75th day, respectively. RESULT: The obvious relationship between CPT content and nitrogen forms was observed. When NH4(+) - N /NO3(-) -N ratio was 25 : 75, CPT accumulation in young leaves displayed the best advantages (the highest value is 5.69 per thousand) and increased in the early 30 days of treatment and then declined. There was no obvious relationship between TSB activity in the young leaves and nitrogen forms. TDC activity in the stem bark was the highest when NH4(+) -N /NO3(-) -N ratio was 25 : 75, and the change of TDC activity paralleled to CPT content in the young leaves. CONCLUSION: A short-term treatment that NH4(+) -N /NO3(-) -N ratio was 25:75 may gain high CPT content in the young leaves through enhancing the TDC activity in the stem bark of C. acuminata seedlings.


Assuntos
Camptotheca/efeitos dos fármacos , Camptotheca/enzimologia , Camptotecina/metabolismo , Nitrogênio/química , Nitrogênio/farmacologia , Plântula/efeitos dos fármacos , Plântula/enzimologia , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Camptotheca/metabolismo , Medicamentos de Ervas Chinesas/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Plântula/metabolismo , Triptofano Sintase/metabolismo
11.
Zhongguo Zhong Yao Za Zhi ; 33(4): 356-9, 2008 Feb.
Artigo em Zh | MEDLINE | ID: mdl-18533483

RESUMO

OBJECTIVE: To investigate the effects of nitrogen concentration on the camptothecin (CPT) content in Camptotheca acuminata seedlings: METHOD: The seedlings of C. acuminata with 6 pair of leaves were subjected to five nitrogen concentrations treatments by sand culture in a greenhouse. The CPT content in the seedlings was determined by HPLC on the 20th, 35th, 50th, 65th and 80th day respectively. RESULT: The CPT content in the young leaves of C. acuminata seedlings supplied with different nitrogen concentration was significantly higher than that in other organs (P < 0.01), and it showed a single peak curve with the time course, the highest CPT content was observed on the 50th day after treatment. The CPT content in the young leaves obviously declined with increasing nitrogen concentration, and it reached the highest (6.72%) when nitrogen concentration was 4 mmol x L(-1), equal to 1.1 times that of 16 mmol x L(-1) nitrogen. CONCLUSION: The results demonstrate that proper deficient nitrogen stress can significantly enhance CPT accumulation in young leaves of C. acuminata seedlings.


Assuntos
Camptotheca/efeitos dos fármacos , Camptotheca/metabolismo , Camptotecina/metabolismo , Nitrogênio/farmacologia , Plântula/efeitos dos fármacos , Plântula/metabolismo , Cromatografia Líquida de Alta Pressão
12.
Fitoterapia ; 124: 152-159, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29122633

RESUMO

Seven new compounds were isolated from the aerial part of Hedyotis diffusa, including three iridoid glycosides, hedyoiridoidside A - C (1-3), two cerebrosides, hedyocerenoside F (4) and G (5), and two new ceramides, hedyoceramide A (6) and B (7). And six known iridoid glycosides (8-13) were also obtained. Their structures were established by their physico-chemical constants and spectroscopic analysis. The cytotoxicity of all compounds against tumor cell lines of human cervical cancer HeLa, human leukemia HL-60, human lung cancer A459, human hepatoma HepG2, human gastric gland carcinoma BCG-823, human nasopharyngeal cancer CNE-2, human colon cancer HCT15, and human prostate cancer PC-3 were also evaluated in vitro. As a result, new compound 1 exhibited evident cytotoxicity to all tumor cell lines, and the IC50 values are from 9.5µM to 28.2µM, while new compound 2 exhibited evident cytotoxicity to Hela, HL-60, A459, HepG2, BGC-823, CNE-2, and HCT15, and the IC50 values are from 15.8µM to 26.2µM. Known compound 11 also exhibited evident cytotoxicity to HL-60, A459, HepG2, BGC-823, CNE-2, and HCT15, and the IC50 values are from 16.5µM to 40.4µM. New compounds 4-7 and known compounds 12 and 13 showed moderate cytotoxicity to some tumor cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Hedyotis/química , Glicosídeos Iridoides/isolamento & purificação , Esfingolipídeos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Componentes Aéreos da Planta/química
13.
PLoS One ; 9(6): e98513, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24892779

RESUMO

The use of acetylsalicylic acid (ASP) is limited by its adverse effects, especially the effect on the gastric mucosa. To address this problem, we synthesized a derivative form of ASP, prepared by modification of ASP with nano-hydroxyapatite (a kind of inorganic particle containing Ca(2+)). The derivative was named Ca-ASP. Structural study showed that Ca-ASP was a kind of carboxylate containing intramolecular hydrogen bonds. Rats given a high dose of Ca-ASP (5 mmol per kg body weight) showed similar anti-thrombotic activity as those given the same dose of ASP, but had much lower gastric mucosal damage than ASP (UI: 2 versus UI: 12.5). These rats also showed reduced expression of COX-2, but their COX-1 expression was similar to that of control rats, but significantly higher than that of ASP-administered rats. Furthermore, the level of prostaglandin E2 (PGE2) was up-regulated in Ca-ASP-administered rats compared to ASP-administered rats. Taken together, the results showed that Ca-ASP possessed similar antithrombotic activity as ASP but without the side effect associated with ASP, and the underlying mechanism may center on inhibiting COX-2 without inhibiting COX-1, and thus favouring the production of PGE2, the prostaglandin that plays a vital role in the suppression of platelet aggregation and thrombosis, as well as in the repair of gastric damage.


Assuntos
Aspirina/farmacologia , Mucosa Gástrica/metabolismo , Animais , Aspirina/análogos & derivados , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/genética , Dinoprostona/metabolismo , Feminino , Mucosa Gástrica/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier
14.
PLoS One ; 8(3): e59989, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23527291

RESUMO

Trauma and sepsis can cause acute lung injury (ALI) and Acute Respiratory Distress Syndrome (ARDS) in part by triggering neutrophil (PMN)-mediated increases in endothelial cell (EC) permeability. We had shown that mitochondrial (mt) damage-associated molecular patterns (DAMPs) appear in the blood after injury or shock and activate human PMN. So we now hypothesized that mitochondrial DAMPs (MTD) like mitochondrial DNA (mtDNA) and peptides might play a role in increased EC permeability during systemic inflammation and proceeded to evaluate the underlying mechanisms. MtDNA induced changes in EC permeability occurred in two phases: a brief, PMN-independent 'spike' in permeability was followed by a prolonged PMN-dependent increase in permeability. Fragmented mitochondria (MTD) caused PMN-independent increase in EC permeability that were abolished with protease treatment. Exposure to mtDNA caused PMN-EC adherence by activating expression of adherence molecule expression in both cell types. Cellular activation was manifested as an increase in PMN calcium flux and EC MAPK phosphorylation. Permeability and PMN adherence were attenuated by endosomal TLR inhibitors. EC lacked formyl peptide receptors but were nonetheless activated by mt-proteins, showing that non-formylated mt-protein DAMPs can activate EC. Mitochondrial DAMPs can be released into the circulation by many processes that cause cell injury and lead to pathologic endothelial permeability. We show here that mitochondria contain multiple DAMP motifs that can act on EC and/or PMN via multiple pathways. This can enhance PMN adherence to EC, activate PMN-EC interactions and subsequently increase systemic endothelial permeability. Mitochondrial DAMPs may be important therapeutic targets in conditions where inflammation pathologically increases endothelial permeability.


Assuntos
Lesão Pulmonar Aguda/fisiopatologia , Permeabilidade da Membrana Celular/fisiologia , Células Endoteliais/fisiologia , Neutrófilos/metabolismo , Síndrome do Desconforto Respiratório/fisiopatologia , Partículas Submitocôndricas/metabolismo , Western Blotting , Adesão Celular/fisiologia , Técnicas de Cultura de Células , Células Cultivadas , DNA Mitocondrial/metabolismo , Humanos , Microscopia Confocal , Reação em Cadeia da Polimerase , Partículas Submitocôndricas/patologia
15.
Shock ; 39(1): 55-62, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23247122

RESUMO

Systemic inflammatory response syndrome (SIRS) is a fundamental host response common to bacterial infection and sterile tissue injury. Systemic inflammatory response syndrome can cause organ dysfunction and death, but its mechanisms are incompletely understood. Moreover, SIRS can progress to organ failure or death despite being sterile or after control of the inciting infection. Biomarkers discriminating between sepsis, sterile SIRS, and postinfective SIRS would therefore help direct care. Circulating mitochondrial DNA (mtDNA) is a damage-associated molecular pattern reflecting cellular injury. Circulating bacterial 16S DNA (bDNA) is a pathogen-associated pattern (PAMP) reflecting ongoing infection. We developed quantitative polymerase chain reaction assays to quantify these markers, and predicting their plasma levels might help distinguish sterile injury from infection. To study these events in primates, we assayed banked serum from Papio baboons that had undergone a brief challenge of intravenous Bacillus anthracis delta Sterne (modified to remove toxins) followed by antibiotics (anthrax) that causes organ failure and death. To investigate the progression of sepsis to "severe" sepsis and death, we studied animals where anthrax was pretreated with drotrecogin alfa (activated protein C), which attenuates sepsis in baboons. We also contrasted lethal anthrax bacteremia against nonlethal E. coli bacteremia and against sterile tissue injury from Shiga-like toxin 1. Bacterial DNA and mtDNA levels in timed samples were correlated with blood culture results and assays of organ function. Sterile injury by Shiga-like toxin 1 increased mtDNA, but bDNA was undetectable: consistent with the absence of infection. The bacterial challenges caused parallel early bDNA and mtDNA increases, but bDNA detected pathogens even after bacteria were undetectable by culture. Sublethal E. coli challenge only caused transient rises in mtDNA consistent with a self-limited injury. In lethal anthrax challenge (n = 4), bDNA increased transiently, but mtDNA levels remained elevated until death, consistent with persistent septic tissue damage after bacterial clearance. Critically, activated protein C pretreatment (n = 4) allowed mtDNA levels to decay after bacterial clearance with sparing of organ function and survival. In summary, host tissue injury correlates with mtDNA whether infective or sterile. Mitochondrial DNA and bDNA polymerase chain reactions can quantify tissue injury incurred by septic or sterile mechanisms and suggest the source of SIRS of unknown origin.


Assuntos
Antraz/diagnóstico , Bacteriemia/diagnóstico , DNA Bacteriano/sangue , DNA Mitocondrial/sangue , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Animais , Antraz/tratamento farmacológico , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Biomarcadores/sangue , Diagnóstico Diferencial , Progressão da Doença , Coagulação Intravascular Disseminada/diagnóstico , Coagulação Intravascular Disseminada/microbiologia , Infecções por Escherichia coli/diagnóstico , Insuficiência de Múltiplos Órgãos/diagnóstico , Insuficiência de Múltiplos Órgãos/microbiologia , Papio , Proteína C/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Análise de Sobrevida , Síndrome de Resposta Inflamatória Sistêmica/microbiologia
16.
J Ethnopharmacol ; 148(1): 37-44, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23567033

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Caesalpinia sappan L. is distributed in Southeast Asia and also used as herbal medicine for the treatment of various diseases such as burning sensations, leprosy, dysentery, osteoarthritis and rheumatoid arthritis (RA). The overproduction of IL-6 plays an important role in the prognosis of RA, but the active compounds from the extracts of Caesalpinia sappan L. suppressing IL-6 production remain unknown. AIMS OF THE STUDY: Identifying the main active compounds of Caesalpinia sappan L. extracts inhibiting the IL-6 production in LPS-stimulated RAW 264.7 cells by partial least squares (PLS). MATERIALS AND METHODS: Sixty-four samples with different proportions of compounds were prepared from Caesalpinia sappan L. by supercritical CO2 fluid extraction (SCFE) and refluxing. Each of 64 samples was applied to RAW 264.7 cells with LPS to evaluate whether IL-6 production by LPS is affected by addition of each sample. The IL-6 production in medium was determined by ELISA and the inhibitory activity of each sample was analyzed. In addition, the fingerprints of these 64 samples were also established by ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-MS). We used the PLS, a simplified method, to evaluate the results from IL-6 production and fingerprints. RESULTS: Each of 64 samples markedly suppressed LPS-induced IL-6 production in RAW cells. The fingerprints by UPLC-MS clearly revealed variations among 64 samples produced in different extract conditions. The PLS analysis with IL-6 production and fingerprints by UPLC-MS suggested that the peaks 71, 93, 150, 157, 168 have more influence on the inhibitory activity of Caesalpinia sappan L. extracts. The peaks 71, 93, 150 are likely representing sappanone A, protosappanin E and neoprotosappanin, respectively. The peaks 157 and 168 are still at large. CONCLUSION: This is the first report that sappanone A, protosappanin E, neoprotosappanin and two unidentified compounds can be considered as possible active compounds that might inhibit IL-6 production. Further studies are needed to confirm the effectiveness of these five compounds on IL-6 production and possible mechanism.


Assuntos
Caesalpinia , Interleucina-6/antagonistas & inibidores , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Etanol/química , Interleucina-6/metabolismo , Análise dos Mínimos Quadrados , Lipopolissacarídeos , Camundongos , Extratos Vegetais/análise , Solventes/química , Madeira/química
17.
J Ethnopharmacol ; 136(1): 271-8, 2011 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-21557995

RESUMO

AIM OF THIS STUDY: To confirm the anti-arthritic effect and explore the potential mechanism of the dried heartwood of Caesalpinia sappan L. (HCS) on collagen-induced arthritis (CIA) in rats, an animal model of rheumatoid arthritis. MATERIALS AND METHODS: CIA was induced in male Wistar rats by intradermal injection of bovine collagen-II in Freund's incomplete adjuvant (IFA). The rats in the onset of arthritis were treated daily with oral administration of an ethanol extract from HCS (EHCS) at different doses (1.2, 2.4 and 3.6g/kg) or olive oil-vehicle for 10 days. Paw swelling, arthritis index, radiographic and histopathologic changes were evaluated to confirm the anti-arthritic effect of EHCS on CIA in rats. Levels of proinflammatory cytokines interleukin-1 beta (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) as well as prostaglandin E2 (PGE2) in blood and expression of cyclooxygenase-2 (COX-2) and transcription factor NF-κB p65 in paw cartilage were detected to further study the molecular mechanism of the anti-arthritic effects of EHCS on CIA in rats. In addition, the adverse effects of EHCS on liver and kidney of rats were also evaluated. RESULTS: The results showed that the EHCS markedly attenuated collagen-induced arthritis and reduced the levels of IL-1ß, IL-6, TNF-α and PGE2 in serum and the expression of COX-2 and transcription factor NF-κB p65 in paw cartilage of CIA rats. EHCS (3.6g/kg) induced slight hepatotoxicity and body weight loss. CONCLUSION: These results indicate that EHCS significantly attenuates CIA in rats by decreasing the levels of IL-1ß, IL-6, TNF-α and PGE2 in serum and the expression of COX-2 and transcription factor NF-κB in paw cartilage.


Assuntos
Anti-Inflamatórios/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Caesalpinia , Cartilagem/metabolismo , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Caesalpinia/efeitos adversos , Bovinos , Colágeno Tipo II , Citocinas/metabolismo , Modelos Animais de Doenças , Adjuvante de Freund , Mediadores da Inflamação/metabolismo , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Madeira
18.
Shock ; 36(6): 548-52, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21937948

RESUMO

Bacterial DNA (bDNA) contains hypomethylated "CpG" repeats that can be recognized by Toll-like receptor 9 (TLR-9) as a pathogen-associated molecular pattern. The ability of bDNA to initiate lung injury via TLR-9 has been inferred on the basis of studies using artificial CpG DNA. But the role of authentic bDNA in lung injury is still unknown. Moreover, the mechanisms by which CpG DNA species can lead to pulmonary injury are unknown, although neutrophils (PMNs) are thought to play a key role in the genesis of septic acute lung injury. We evaluated the effects of bDNA on PMN-endothelial cell (EC) interactions thought critical for initiation of acute lung injury. Using a biocapacitance system to monitor real-time changes in endothelial permeability, we demonstrate here that bDNA causes EC permeability in a dose-dependent manner uniquely in the presence of PMNs. These permeability changes are inhibited by chloroquine, suggesting TLR-9 dependency. When PMNs were preincubated with bDNA and applied to ECs or when bDNA was applied to ECs without PMNs, no permeability changes were detected. To study the underlying mechanisms, we evaluated the effects of bDNA on PMN-EC adherence. Bacterial DNA significantly increased PMN adherence to ECs in association with upregulated adhesion molecules in both cell types. Taken together, our results strongly support the conclusion that bDNA can initiate lung injury by stimulating PMN-EC adhesive interactions predisposing to endothelial permeability. Bacterial DNA stimulation of TLR-9 appears to promote enhanced gene expression of adhesion molecules in both cell types. This leads to PMN-EC cross-talk, which is required for injury to occur.


Assuntos
DNA Bacteriano/farmacologia , Endotélio Vascular/efeitos dos fármacos , Neutrófilos/metabolismo , Receptor Toll-Like 9/metabolismo , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Antígenos CD18/genética , Antígenos CD18/metabolismo , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Linhagem Celular , Células Cultivadas , Selectina E/genética , Selectina E/metabolismo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Neutrófilos/citologia , Receptor Toll-Like 9/genética
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