RESUMO
Helminth infections and their components has been recognized to have a positive impact on the immune system. This study aimed to investigate the potential of Metagonimus yokogawai-derived proteins (MYp) to provide protection against ankylosing spondylitis (AS) through modulation of immune responses. The cytotoxicity of MYp at various doses was first assessed using MTS and flow cytometry. Peripheral blood mononuclear cells (PBMCs) were collected from AS patients, and the production of inflammatory cytokines was analyzed through flow cytometry. In the experiments with SKG mice, MYp or vehicle was administered and inflammation was evaluated through immunohistochemistry and enzyme-linked immunosorbent assay. The results showed that MYp did not decrease cell viability of PBMCs even after 48 h. Additionally, the frequencies of IFN-γ and IL-17A producing cells were significantly reduced after MYp treatment in the PBMC cultures. Furthermore, MYp treatment significantly suppressed arthritis and enthesitis in the SKG mouse model. The results suggest the first evidence that MYp can effectively alleviate clinical symptoms and restore cytokine balance in patients with AS.
Assuntos
Heterophyidae , Espondilite Anquilosante , Humanos , Animais , Camundongos , Espondilite Anquilosante/tratamento farmacológico , Leucócitos Mononucleares , Citocinas/metabolismo , Inflamação/tratamento farmacológicoRESUMO
The present study firstly reports surface sediment from the subsea depth of 200 m as a potential natural peloid. The fine-silt sediment exhibited a consistent clay mineral composition dominated by illite, chlorite, kaolinite, and diatomite. The most abundant clay mineral was illite/mica, with other minerals loosely packed in a face-to-face orientation. The thermal conductivity, specific heat capacity, and cation-exchange capacity of the sediment were in the range 0.855-0.885 W/m K, 2.718-2.821 J/g °C, and 23.06-32.96 cmol/kg, respectively. The concentrations of most toxic elements in the sediment were considerably lower than the limits set by domestic cosmetic regulations and other international standards. The analyzed samples exhibited similar properties to those of previously reported peloids, thus making them suitable for use in the field of pelotherapy; furthermore, the consistency in data across a wide peloid-distribution area is expected to enable economically viable mining. Future investigations should aim to to evaluate the long-term effects on the skin, the bioavailability of potentially hazardous substances, and the therapeutic efficacy for various skin conditions.
Assuntos
Argila , Sedimentos Geológicos , Peloterapia , Sedimentos Geológicos/química , República da Coreia , Argila/química , Silicatos de Alumínio/química , Minerais/química , Minerais/análise , Monitoramento Ambiental/métodosRESUMO
OBJECTIVES: Th17 cells are known to play a significant role in AS. C-C motif chemokine ligand 20 (CCL20) binds to C-C chemokine receptor 6 (CCR6) on Th17 cells, promoting their migration to inflammation sites. The aim of this research is to examine the effectiveness of CCL20 inhibition in treating inflammation in AS. METHODS: Mononuclear cells from peripheral blood (PBMC) and SF (SFMC) were collected from healthy individuals and AS. Flow cytometry was used to analyse cells producing inflammatory cytokines. CCL20 levels were determined using ELISA. The impact of CCL20 on Th17 cell migration was verified using a Trans-well migration assay. The in vivo efficacy of CCL20 inhibition was evaluated using an SKG mouse model. RESULTS: The presence of Th17 cells and CCL20 expressing cells was higher in SFMCs from AS patients compared with their PBMCs. The CCL20 level in AS SF was significantly higher than in OA patients. The percentage of Th17 cells in PBMCs from AS patients increased when exposed to CCL20, whereas the percentage of Th17 cells in SFMCs from AS patients decreased when treated with CCL20 inhibitor. The migration of Th17 cells was found to be influenced by CCL20, and this effect was counteracted by the CCL20 inhibitor. In the SKG mouse model, the use of CCL20 inhibitor significantly reduced joint inflammation. CONCLUSION: This research validates the critical role of CCL20 in AS and suggests that targeting CCL20 inhibition could serve as a novel therapeutic approach for AS treatment.
Assuntos
Espondilite Anquilosante , Camundongos , Animais , Humanos , Espondilite Anquilosante/metabolismo , Ligantes , Leucócitos Mononucleares/metabolismo , Quimiocina CCL20/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Células Th17/metabolismo , Modelos Animais de Doenças , Receptores CCR6/metabolismoRESUMO
Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease, which is characterized by inflammation of the axial skeleton and the peripheral arthritis. An increase in the number of Th17 cells in patients with AS has been reported. Although Th17 cells have been involved in the induction of inflammation, recent data suggest that not all Th17 cells are pathogenic, showing regulatory function of Th17 cell. Cells producing both interferon-gamma (IFN-γ) and interleukin (IL)-17 have been reported to be the main pathologic Th17 (pTh17) cells that induce inflammation at sites of joint. Emerging evidence demonstrated that IL-6 has a main role in regulating the balance between inflammatory and regulatory T cells. However, there is no direct study to assess pTh17 cell with IL-6 in AS. Therefore, we evaluated the effect of IL-6 on pTh17 cell activation, and it's mechanism, using ex vivo and mouse model of AS. As a result, we found that pTh17 cell is dependent on the cytokine milieu with IL-6. We confirmed pTh17 cells play a pathogenic role at sites of inflammation. As a mechanism, it was revealed that IL-6 induced STAT 3 phosphorylation contributes to the increased pTh17 responses in AS patients with peripheral arthritis. Though validation of our results is required, IL-6 inhibitor can be a promising treatment for inflammation in AS patients with peripheral arthritis.
Assuntos
Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Espondilite Anquilosante , Células Th17 , Animais , Humanos , Inflamação , Camundongos , Fosforilação , Espondilite Anquilosante/patologia , Células Th17/patologiaRESUMO
OBJECTIVE: To assess the associations between the triglyceride glucose (TyG) index and modified TyG indices with nonalcoholic fatty liver disease (NAFLD) and evaluate their ability as predictors of NAFLD in youths. STUDY DESIGN: We analyzed the cross-sectional data of 3728 individuals aged 10-19 years using the Korea National Health and Nutrition Examination Survey, a nationally representative survey. Logistic regression analysis was performed, and ORs and 95% CIs of tertiles 2 and 3 for each variable for predicting NAFLD were calculated and compared with those of tertile 1 as the reference. Receiver operating characteristic (ROC) curves were plotted to evaluate the ability of each variable for NAFLD prediction. RESULTS: All TyG and modified TyG indices exhibited progressively increased ORs and 95% CIs for NAFLD across all tertiles (all P < .001). In addition, all TyG and modified TyG indices significantly predicted NAFLD through ROC curves. All modified TyG indices were superior to the TyG index for predicting NAFLD in all subjects and in males. Among females, the TyG-waist-to-height ratio was superior to the TyG index, TyG-body mass index (BMI), and TyG-waist circumference (WC), and the TyG-BMI SDS and TyG-WC were superior to the TyG index. CONCLUSIONS: The TyG and modified TyG indices are markers for NAFLD prediction in youths, and the modified TyG indices are superior to the TyG index. Modified TyG indices have the potential to be simple and cost-effective markers in screening for NAFLD in youths.
Assuntos
Hepatopatia Gordurosa não Alcoólica , Adolescente , Biomarcadores , Glicemia , Estudos Transversais , Feminino , Glucose , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Inquéritos Nutricionais , TriglicerídeosRESUMO
This paper proposes a collision avoidance algorithm for the detection and avoidance capabilities of Unmanned Aerial Vehicles (UAVs). The proposed algorithm aims to ensure minimum separation between UAVs and geofencing with multiple no-fly zones, considering the sensor uncertainties. The main idea is to compute the collision probability and to initiate collision avoidance manoeuvres determined by the differential geometry concept. The proposed algorithm is validated by both theoretical and numerical analysis. The results indicate that the proposed algorithm ensures minimum separation, efficiency, and scalability compared with other benchmark algorithms.
Assuntos
Algoritmos , Benchmarking , Probabilidade , IncertezaRESUMO
Osteopenia or osteoporosis occurs frequently in alcoholics and patients with alcoholic fatty liver disease. Methoxsalen (MTS), 8-methoxypsoralen, improved osteoporosis in ovariectomized and diabetic mouse models; however, its effects on alcohol-induced osteopenia and steatosis have not been reported. This study examined the effects of MTS on alcohol-induced bone loss and steatosis. Rats in the alcohol groups were fed a Liber-DeCarli liquid diet containing 36% of its calories as alcohol. MTS was at 0.005% in their diet, while alendronate (positive control; 500 µg/kg BW/day) was administered orally for eight weeks. The pair-fed group received the same volume of isocaloric liquid diet containing dextrin-maltose instead of alcohol as the alcohol control group consumed the previous day. In the alcohol-fed rats, the MTS and alendronate increased the bone volume density, bone surface density and trabecular number, while the bone specific surface, trabecular separation and structure model index were decreased in the tibia. MTS down-regulated tibial tartrate-resistant acid phosphatase 5 (TRAP) expression compared to the alcohol control group. MTS or alendronate prevented chronic alcohol-induced hepatic lipid accumulation and the triglyceride level in the alcohol-fed rats by decreasing the lipogenic enzyme activities and increasing the fatty acid oxidation enzyme activities. MTS reduced significantly the serum levels of alcohol, TRAP and tumor necrosis factor-α compared to the alcohol control group. Overall, these results suggest that MTS is likely to be an alternative agent for alcoholic osteopenia and hepatosteatosis.
Assuntos
Alcoolismo/complicações , Doenças Ósseas Metabólicas/etiologia , Suplementos Nutricionais , Fígado Gorduroso/etiologia , Metoxaleno/farmacologia , Substâncias Protetoras/farmacologia , Animais , Biomarcadores , Doenças Ósseas Metabólicas/tratamento farmacológico , Doenças Ósseas Metabólicas/patologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Citocinas/sangue , Citocinas/metabolismo , Modelos Animais de Doenças , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/patologia , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , RatosRESUMO
Gentiopicroside is a major active component of the Gentiana scabra Bge., which is commonly used as herbal medicine for the treatment of inflammation in Asia. Gentiopicroside significantly down-regulated expression of key adipogenic transcription factors (PPARγ, C/EBPα, SREBP-1c) and dose-dependently inhibited the lipid uptake-related gene (LPL), fatty acid transport-related gene (FABP4) and triglyceride (TG) synthesis-related gene (DGAT2), as well as fatty acid synthesis-related genes (FAS, SCD1), which resulted in reduced intracellular lipid droplet accumulation and TG content in 3T3-L1 cells. Gentiopicroside also down-regulated expression of inflammatory cytokine genes (NFκB1, TNFα, IL6) compared with vehicle. Oral administration of gentiopicroside (50â¯mg/kg) in mice fed with high-fat diet for 12â¯weeks resulted in reduced body weight and visceral fat mass compared with the control group. Overall, the results of this study showed that gentiopicroside had positive anti-obesity effects by regulating the expression of adipogenesis/lipogenesis-related genes and inflammatory genes in 3T3-L1, and that it effectively reduced body weight and visceral fat mass in vivo.
Assuntos
Células 3T3-L1/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Fármacos Antiobesidade/uso terapêutico , Peso Corporal/efeitos dos fármacos , Gentiana/química , Glucosídeos Iridoides/uso terapêutico , Animais , Fármacos Antiobesidade/farmacologia , Glucosídeos Iridoides/farmacologia , Masculino , Camundongos , Camundongos ObesosRESUMO
This study evaluated whether bergapten and methoxsalen could prevent diabetes-induced osteoporosis and its underlying mechanism. For 10 weeks, bergapten or methoxsalen (0.02%, w/w) was applied to diabetic mice that were provided with a high-fat diet and streptozotocin. Bone mineral density (BMD) and microarchitecture quality were significantly reduced in the diabetic control group; however, both bergapten and methoxsalen reversed serum osteocalcin, bone-alkaline phosphatase and femur BMD. These coumarin derivatives significantly increased bone volume density and trabecular number, whereas they decreased the structure model index of femur tissue in diabetic mice. Conversely, tartrate-resistant acid phosphatase 5 (TRAP) staining revealed that these derivatives reduced osteoclast numbers and formation in diabetic bone tissue. Additionally, both bergapten and methoxsalen tended to downregulate the expression of osteoclast-related genes such as receptor activator of nuclear factor kappa-B ligand (RANKL), nuclear of activated T-cells, cytoplasmic 1 (NFATc1) and TRAP in diabetic femurs, with NFATc1 and TRAP expression showing significant reductions. Our data suggest that both bergapten and methoxsalen prevent diabetic osteoporosis by suppressing bone resorption.
Assuntos
5-Metoxipsoraleno/administração & dosagem , Diabetes Mellitus Experimental/complicações , Metoxaleno/administração & dosagem , Osteogênese/efeitos dos fármacos , Osteoporose/prevenção & controle , 5-Metoxipsoraleno/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Densidade Óssea/efeitos dos fármacos , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/genética , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Metoxaleno/farmacologia , Camundongos , Fatores de Transcrição NFATC/genética , Osteocalcina/sangue , Osteoporose/genética , Ligante RANK/genética , Estreptozocina , Fosfatase Ácida Resistente a Tartarato/genéticaRESUMO
KCNK1 (K(+) channel, subfamily K, member 1) is a member of the inwardly rectifying K(+) channel family, which drives the membrane potential towards the K(+) balance potential. Here, we investigated its functional relevance during osteoclast differentiation. KCNK1 was significantly induced during osteoclast differentiation, but its functional overexpression significantly inhibited osteoclast differentiation induced by RANKL (also known as TNFSF11), which was accompanied by the attenuation of the RANKL-induced Ca(2+) oscillation, JNK activation and NFATc1 expression. In contrast, KCNK1 knockdown enhanced the RANKL-induced osteoclast differentiation, JNK activation and NFATc1 expression. In conclusion, we suggest that KCNK1 is a negative regulator of osteoclast differentiation; the increase of K(+) influx by its functional blockade might inhibit osteoclast differentiation by inhibiting Ca(2+) oscillation and the JNK-NFATc1 signaling axis. Together with the increased attention on the pharmacological possibilities of using channel inhibition in the treatment of osteoclast-related disorders, further understanding of the functional roles and mechanisms of K(+) channels underlying osteoclast-related diseases could be helpful in developing relevant therapeutic strategies.
Assuntos
Sinalização do Cálcio , Sistema de Sinalização das MAP Quinases , Osteoclastos/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Regulação para Baixo , Técnicas de Silenciamento de Genes , Camundongos , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/citologia , Canais de Potássio de Domínios Poros em Tandem/genética , Ligante RANK/metabolismoRESUMO
Photostimulation with low-level light emitting diode therapy (LED-T) modulates neurological and psychological functions. The purpose of this study was to evaluate the effects of LED-T pretreatment on the mouse brain after ischemia/reperfusion and to investigate the underlying mechanisms. Ischemia/reperfusion brain injury was induced by middle cerebral artery occlusion. The mice received LED-T twice a day for 2 days prior to cerebral ischemia. After reperfusion, the LED-T group showed significantly smaller infarct and edema volumes, fewer behavioral deficits compared to injured mice that did not receive LED-T and significantly higher cerebral blood flow compared to the vehicle group. We observed lower levels of endothelial nitric oxide synthase (eNOS) phosphorylation in the injured mouse brains, but significantly higher eNOS phosphorylation in LED-T-pretreated mice. The enhanced phospho-eNOS was inhibited by LY294002, indicating that the effects of LED-T on the ischemic brain could be attributed to the upregulation of eNOS phosphorylation through the phosphoinositide 3-kinase (PI3K)/Akt pathway. Moreover, no reductions in infarct or edema volume were observed in LED-T-pretreated eNOS-deficient (eNOS-/-) mice. Collectively, we found that pretreatment with LED-T reduced the amount of ischemia-induced brain damage. Importantly, we revealed that these effects were mediated by the stimulation of eNOS phosphorylation via the PI3K/Akt pathway.
Assuntos
Lesões Encefálicas/enzimologia , Lesões Encefálicas/terapia , Isquemia Encefálica/enzimologia , Isquemia Encefálica/terapia , Óxido Nítrico Sintase Tipo III/metabolismo , Fototerapia/instrumentação , Animais , Lesões Encefálicas/etiologia , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico , Luz , Iluminação/instrumentação , Iluminação/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fototerapia/métodos , Cuidados Pré-Operatórios/métodos , Doses de Radiação , Semicondutores , Resultado do TratamentoRESUMO
Scopoletin is a bioactive component in many edible plants and fruits. This study investigated the effects of scopoletin on hepatic steatosis and inflammation in a high-fat diet fed type 1 diabetic mice by comparison with metformin. Scopoletin (0.01%, w/w) or metformin (0.5%, w/w) was provided with a high-fat diet to streptozotocin-induced diabetic mice for 11 weeks. Both scopoletin and metformin lowered blood glucose and HbA1c , serum ALT, TNF-α and IL-6 levels, glucose intolerance, and hepatic lipid accumulation compared with the diabetic control group. Scopoletin or metformin down-regulated hepatic gene expression of triglyceride (Pparg, Plpp2, and Dgat2) and cholesterol (Hmgcr) synthesis as well as inflammation (Tlr4, Myd88, Nfkb1, Tnfa, and Il6), while it up-regulated Cyp7a1 gene. Hepatic PPARγ and DGAT2 protein levels were also down-regulated in scopoletin or metformin group compared with the control group. Scopoletin or metformin also inhibited hepatic fatty acid synthase and phosphatidate phosphohydrolase activities. These results suggest that scopoletin protects against diabetes-induced steatosis and inflammation by inhibiting lipid biosynthesis and TLR4-MyD88 pathways. Copyright © 2017 John Wiley & Sons, Ltd.
Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Fígado Gorduroso/tratamento farmacológico , Inflamação/tratamento farmacológico , Escopoletina/farmacologia , Animais , Glicemia/efeitos dos fármacos , Colesterol/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Dieta Hiperlipídica , Suplementos Nutricionais , Fígado Gorduroso/sangue , Intolerância à Glucose , Hemoglobinas/análise , Interleucina-6/sangue , Fígado/efeitos dos fármacos , Masculino , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
Nanostructured silicon (Si) is useful in many applications and has typically been synthesized by bottom-up colloid-based solution processes or top-down gas phase reactions at high temperatures. These methods, however, suffer from toxic precursors, low yields, and impractical processing conditions (i.e., high pressure). The magnesiothermic reduction of silicon oxide (SiO2) has also been introduced as an alternative method. Here, we demonstrate the reduction of SiO2 by a simple milling process using a lab-scale planetary-ball mill and industry-scale attrition-mill. Moreover, an ignition point where the reduction begins was consistently observed for the milling processes, which could be used to accurately monitor and control the reaction. The complete conversion of rice husk SiO2 to high purity Si was demonstrated, taking advantage of the rice husk's uniform nanoporosity and global availability, using a 5L-scale attrition-mill. The resulting porous Si showed excellent performance as a Li-ion battery anode, retaining 82.8% of the initial capacity of 1466 mAh g-1 after 200 cycles.
RESUMO
The caudal subnucleus of the spinal trigeminal nucleus (medullary dorsal horn; MDH) receives direct inputs from small diameter primary afferent fibers that predominantly transmit nociceptive information in the orofacial region. Recent studies indicate that reactive oxygen species (ROS) is involved in persistent pain, primarily through spinal mechanisms. In this study, we aimed to investigate the role of xanthine/xanthine oxidase (X/XO) system, a known generator of superoxide anion (O2·-), on membrane excitability in the rat MDH neurons. For this, we used patch clamp recording and confocal imaging. An application of X/XO (300 µM/30 mU) induced membrane depolarization and inward currents. When slices were pretreated with ROS scavengers, such as phenyl N-tert-butylnitrone (PBN), superoxide dismutase (SOD), and catalase, X/XO-induced responses decreased. Fluorescence intensity in the DCF-DA and DHE-loaded MDH cells increased on the application of X/XO. An anion channel blocker, 4,4-diisothiocyanatostilbene-2,2-disulfonic acid (DIDS), significantly decreased X/XO-induced depolarization. X/XO elicited an inward current associated with a linear current-voltage relationship that reversed near -40 mV. X/XO-induced depolarization reduced in the presence of La3+, a nonselective cation channel (NSCC) blocker, and by lowering the external sodium concentration, indicating that membrane depolarization and inward current are induced by influx of Na+ ions. In conclusion, X/XO-induced ROS modulate the membrane excitability of MDH neurons, which was related to the activation of NSCC.
RESUMO
Peucedanum japonicum Thunb is a medicinal plant belonging to the family Umbelliferae. This study evaluated the anti-diabetic and anti-obesity effects of cis-3',4'-diisovalerylkhellactone (cDIVK) isolated from Peucedanum japonicum Thunb leaves. cDIVK (30 and 50µM) effectively inhibited adipocyte differentiation and fat accumulation, whereas it stimulated glucose uptake compared with the control in 3T3-L1 cells. cDIVK significantly increased AMPK activation and suppressed protein and mRNA expression of major adipogenic transcriptional factors such as C/EBPα, PPARγ and SREBP-1c in 3T3-L1 cells. In addition, cDIVK had potential α-glucosidase inhibitory activity. These results indicated that cDIVK may act as a natural dual therapeutic agent for diabetes and obesity.
Assuntos
Fármacos Antiobesidade/farmacologia , Apiaceae/química , Cumarínicos/farmacologia , Hipoglicemiantes/farmacologia , Folhas de Planta/química , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Diferenciação Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Camundongos , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria UltravioletaRESUMO
The Bradyrhizobium japonicum NtrBC two-component system is a critical regulator of cellular nitrogen metabolism, including the acquisition and catabolism of nitrogenous compounds. To better define the roles of this system, genome-wide transcriptional profiling was performed to identify the NtrC regulon during the response to nitrogen limitation. Upon cells perceiving low intracellular nitrogen, they stimulate the phosphorylation of NtrC, which induces genes responsible for alteration of the core glutamine synthetase/glutamate synthase nitrogen assimilation pathway, including the genes for the glutamine synthetases and PII proteins. In addition, genes responsible for the import and utilization of multiple nitrogen sources, specifically nitrate and nitrite, were upregulated by NtrC activation. Mutational analysis of a candidate nitrite reductase revealed a role for NtrC in regulating the assimilation of nitrite, since mutations in both ntrC and the gene encoding the candidate nitrite reductase abolished the ability to grow on nitrite as a sole nitrogen source.
Assuntos
Proteínas de Bactérias/metabolismo , Bradyrhizobium/genética , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Regulon , Bradyrhizobium/metabolismo , DNA Bacteriano/química , DNA Bacteriano/genética , Dados de Sequência Molecular , Nitrogênio/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Sequência de DNARESUMO
A polyphasic approach was used to characterize a novel nitrogen-fixing bacterial strain, designated YC6995(T), isolated from the rhizosphere soil of Iris ensata var. spontanea (Makino) Nakai inhabiting a wetland located at an altitude of 960 m on Jiri Mountain, Korea. Strain YC6995(T) cells were Gram-negative, and rod-shaped, with motility provided by a single polar flagellum. Optimal growth conditions were 30 °C and pH 7.0. The major fatty acids of strain YC6995(T) were C18:1 ω7c, C18:1 2-OH and C16:0 3-OH. The major respiratory quinone was ubiquinone-10 (Q-10). The polar lipids were phosphatidylethanolamine, phosphatidyldimethylethanolamine, phosphatidylcholine, phosphatidylglycerol and unidentified glycolipids. The genomic DNA G+C content was 64.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed strain YC6995(T) to form a phyletic lineage with Nitrospirillum amazonense DSM 2787(T) with a high sequence similarity (97.2 %), but it displayed low sequence similarity with other remotely related genera, including Azospirillum (<93 %), Rhodocista (93.1-93.4 %), and Skermanella (91.2-93.3 %) in the family Alphaproteobacteria. Based on the phenotypic, chemotaxonomic, and phylogenetic evidences, strain YC6995(T) represents a novel species within the genus Nitrospirillum, for which the name Nitrospirillum irinus sp. nov. is proposed. The type strain is YC6995(T) (= KACC 13777(T) = DSM 22198(T)). An emended description of the genus Nitrospirillum is also proposed.
Assuntos
Rhodospirillaceae/classificação , Rhodospirillaceae/isolamento & purificação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Flagelos/fisiologia , Glicolipídeos/análise , Concentração de Íons de Hidrogênio , Iris/microbiologia , Locomoção , Dados de Sequência Molecular , Fixação de Nitrogênio , Fosfolipídeos/análise , Filogenia , Quinonas/análise , RNA Ribossômico 16S/genética , República da Coreia , Rizosfera , Rhodospirillaceae/genética , Rhodospirillaceae/fisiologia , Análise de Sequência de DNA , TemperaturaRESUMO
Bradyrhizobium japonicum is a nitrogen-fixing symbiont of soybean. In previous studies, transcriptomic profiling of B. japonicum USDA110, grown under various environmental conditions, revealed the highly induced gene aceA, encoding isocitrate lyase (ICL). The ICL catalyzes the conversion of isocitrate to succinate and glyoxylate in the glyoxylate bypass of the TCA cycle. Here, we evaluated the functional role of B. japonicum ICL under desiccation-induced stress conditions. We purified AceA (molecular mass = 65 kDa) from B. japonicum USDA110, using a His-tag and Ni-NTA column approach, and confirmed its ICL enzyme activity. The aceA mutant showed higher sensitivity to desiccation stress (27% relative humidity (RH)), compared to the wild type. ICL activity of the wild type strain increased approximately 2.5-fold upon exposure to 27% RH for 24 h. The aceA mutant also showed an increased susceptibility to salt stress. Gene expression analysis of aceA using qRT-PCR revealed a 148-fold induction by desiccation, while other genes involved in the glyoxylate pathway were not differentially expressed in this condition. Transcriptome analyses revealed that stress-related genes, such as chaperones, were upregulated in the wild-type under desiccating conditions, even though fold induction was not dramatic (ca. 1.5-2.5-fold).
Assuntos
Proteínas de Bactérias/metabolismo , Bradyrhizobium/metabolismo , Isocitrato Liase/metabolismo , Estresse Fisiológico , Proteínas de Bactérias/genética , Bradyrhizobium/enzimologia , Bradyrhizobium/genética , Dessecação , Isocitrato Liase/genética , TranscriptomaRESUMO
Nitric oxide (NO) is an important signaling molecule involved in nociceptive transmission. It can induce analgesic and hyperalgesic effects in the central nervous system. In this study, patch-clamp recording was used to investigate the effect of NO on neuronal excitability in substantia gelatinosa (SG) neurons of the spinal cord. Different concentrations of sodium nitroprusside (SNP; NO donor) induced a dual effect on the excitability of neuronal membrane: 1 mM of SNP evoked membrane hyperpolarization and an outward current, whereas 10 µM induced depolarization of the membrane and an inward current. These effects were prevented by hemoglobin and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt (c-PTIO) (NO scavengers), phenyl N-tert-butylnitrone (PBN; nonspecific reactive oxygen species scavenger), and through inhibition of soluble guanylyl cyclase (sGC). Pretreatment with n-ethylmaleimide (NEM; thiol-alkylating agent) also decreased effects of both 1 mM and 10 µM SNP, suggesting that these responses were mediated by direct S-nitrosylation. Charybdotoxin (CTX) and tetraethylammonium (TEA) (large-conductance Ca(2+)-activated K(+) channel blockers) and glybenclamide (ATP-sensitive K(+) channel blocker) decreased SNP-induced hyperpolarization. La(3+) (nonspecific cation channel blocker), but not Cs(+) (hyperpolarization-activated K(+) channel blocker), blocked SNP-induced membrane depolarization. In conclusion, NO dually affects neuronal excitability in a concentration-dependent manner via modification of various K(+) channels.
Assuntos
Neurônios/efeitos dos fármacos , Óxido Nítrico/farmacologia , Substância Gelatinosa/citologia , Substância Gelatinosa/efeitos dos fármacos , Alquilantes/farmacologia , Animais , Sequestradores de Radicais Livres , Guanilato Ciclase/metabolismo , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Microscopia de Fluorescência , Óxido Nítrico/antagonistas & inibidores , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Técnicas de Patch-Clamp , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/farmacologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Nitrogênio/metabolismo , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos , Compostos de Sulfidrila/farmacologiaRESUMO
Ursolic acid (UA) is a pentacyclic triterpenoid compound that naturally occurs in fruits, leaves and flowers of medicinal herbs. This study investigated the dose-response efficacy of UA (0.01 and 0.05%) on glucose metabolism, the polyol pathway and dyslipidemia in streptozotocin/nicotinamide-induced diabetic mice. Supplement with both UA doses reduced fasting blood glucose and plasma triglyceride levels in non-obese type 2 diabetic mice. High-dose UA significantly lowered plasma free fatty acid, total cholesterol and VLDL-cholesterol levels compared with the diabetic control mice, while LDL-cholesterol levels were reduced with both doses. UA supplement effectively decreased hepatic glucose-6-phosphatase activity and increased glucokinase activity, the glucokinase/glucose-6-phosphatase ratio, GLUT2 mRNA levels and glycogen content compared with the diabetic control mice. UA supplement attenuated hyperglycemia-induced renal hypertrophy and histological changes. Renal aldose reductase activity was higher, whereas sorbitol dehydrogenase activity was lower in the diabetic control group than in the non-diabetic group. However, UA supplement reversed the biochemical changes in polyol pathway to normal values. These results demonstrated that low-dose UA had preventive potency for diabetic renal complications, which could be mediated by changes in hepatic glucose metabolism and the renal polyol pathway. High-dose UA was more effective anti-dyslipidemia therapy in non-obese type 2 diabetic mice.