RESUMO
OBJECTIVE: This study aimed to investigate the associations between concurrent atrial fibrillation and diabetes-related complications among patients with diabetes. RESEARCH DESIGN AND METHODS: This nationwide observational cohort study used the health checkup database from the Korean National Health Insurance Service. Patients diagnosed with diabetes who underwent health checkups between 2009 and 2012 were investigated. The patients with atrial fibrillation were matched in a 1:5 ratio with those without atrial fibrillation using propensity scores. Study outcomes included macrovascular, microvascular (diabetic retinopathy and diabetic nephropathy), and diabetic foot complications. The risks of clinical outcomes were measured using hazard ratios (HRs) with 95% CIs. RESULTS: A total of 65,760 patients with diabetes were analyzed (54,800 without atrial fibrillation and 10,960 with atrial fibrillation). After well-balanced propensity score matching, atrial fibrillation was associated with significantly higher risks of macrovascular complications (HR 1.12, 95% CI 1.09-1.16), diabetic nephropathy (HR 1.23, 95% CI 1.16-1.30), and diabetic foot complications (HR 1.13, 95% CI 1.09-1.17) compared with no atrial fibrillation, while the risk of diabetic retinopathy was comparable (HR 0.99, 95% CI 0.96-1.03). Patients with atrial fibrillation had a significantly higher risk of diabetic foot amputation (HR 4.12, 95% CI 1.98-8.56). CONCLUSIONS: Among patients with diabetes, concurrent atrial fibrillation was associated with increased risks for diabetes-related macrovascular complications, diabetic nephropathy, and diabetic foot. Such patients require holistic management to reduce the risk of adverse outcomes.
Assuntos
Fibrilação Atrial , Diabetes Mellitus , Pé Diabético , Nefropatias Diabéticas , Retinopatia Diabética , Humanos , Estudos de Coortes , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/complicações , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Nefropatias Diabéticas/complicações , Pé Diabético/complicações , Fatores de RiscoRESUMO
BACKGROUND: Patients with concurrent atrial fibrillation (AF) and diabetes mellitus (DM) [AF-DM] have a high risk of cardiovascular and diabetes-related complications, but are less engaged in a comprehensive treatment approach. We evaluated the association of early rhythm control (ERC), lifestyle modification (LSM), and a combination of ERC and LSM with cardiovascular or diabetes-related complication risk in patients with AF-DM (type 2). METHODS: From the National Health Information Database, 47,940 patients diagnosed with AF-DM in 2009-2016 were included. We defined ERC as rhythm control therapy within two years of AF diagnosis and LSM as adherence to ≥ 2 of the healthy behaviors among non-current smoking, non-drinking, and regular exercise. We compared the primary (ischemic stroke) and secondary (macro- and microvascular complications, glycemic emergency, and all-cause death) outcomes in four groups: non-ERC and non-LSM (group 1), LSM only (group 2), ERC only (group 3), and both ERC and LSM (group 4). RESULTS: Of total, 10,617 (22%), 26,730 (55.8%), 2,903 (6.1%), and 7,690 (16.0%) were classified into groups 1 to 4, in sequence. The mean duration from AF diagnosis to ERC was 25.6 ± 75.5 days. During 4.0 (interquartile range: 2.5-6.2) years' follow-up, groups 2 and 3 were associated with 23% and 33% lower risks of stroke than group 1, respectively. Group 4 was associated with the lowest risk of stroke: hazard ratio (HR) 0.58, 95% confidence interval (CI) 0.51-0.67, p < 0.001. Regarding secondary outcomes, the lowest risks were also observed in group 4; macro- and microvascular complications, glycemic emergency, and all-cause death had HRs (95% CIs) of 0.63 (0.56-0.70), 0.88 (0.82-0.94), 0.72 (0.62-0.84), and 0.80 (0.73-0.87), respectively, all p < 0.001. CONCLUSIONS: For AF-DM patients, ERC and LSM exert a synergistic effect in preventing cardiovascular and diabetes-related complications with the greatest lowered risk of stroke. A comprehensive treatment approach should be pursued in AF-DM patients.
Assuntos
Fibrilação Atrial , Prestação Integrada de Cuidados de Saúde , Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/terapia , Estudos de Coortes , Fatores de Risco , Prognóstico , Diabetes Mellitus Tipo 2/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Complicações do Diabetes/diagnóstico , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/terapia , Estilo de Vida Saudável , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapiaRESUMO
IgE is central to the development of allergic diseases, and its neutralization alleviates allergic symptoms. However, most of these antibodies are based on IgG1, which is associated with an increased risk of fragment crystallizable-mediated side effects. Moreover, omalizumab, an anti-IgE antibody approved for therapeutic use, has limited benefits for patients with high IgE levels. Here, we assess a fusion protein with extracellular domain of high affinity IgE receptor, FcεRIα, linked to a IgD/IgG4 hybrid Fc domain we term IgETRAP, to reduce the risk of IgG1 Fc-mediated side effects. IgETRAP shows enhanced IgE binding affinity compared to omalizumab. We also see an enhanced therapeutic effect of IgETRAP in food allergy models when combined with Bifidobacterium longum, which results in mast cell number and free IgE levels. The combination of IgETRAP and B. longum may therefore represent a potent treatment for allergic patients with high IgE levels.
Assuntos
Bifidobacterium longum , Hipersensibilidade Alimentar , Bifidobacterium longum/metabolismo , Suplementos Nutricionais , Hipersensibilidade Alimentar/terapia , Humanos , Imunoglobulina D , Imunoglobulina E , Imunoglobulina G , Omalizumab/uso terapêutico , Receptores de IgE/metabolismoRESUMO
Despite ongoing advances in our understanding of local single-cellular and network-level activity of neuronal populations in the human brain, extraordinarily little is known about their "intermediate" microscale local circuit dynamics. Here, we utilized ultra-high-density microelectrode arrays and a rare opportunity to perform intracranial recordings across multiple cortical areas in human participants to discover three distinct classes of cortical activity that are not locked to ongoing natural brain rhythmic activity. The first included fast waveforms similar to extracellular single-unit activity. The other two types were discrete events with slower waveform dynamics and were found preferentially in upper cortical layers. These second and third types were also observed in rodents, nonhuman primates, and semi-chronic recordings from humans via laminar and Utah array microelectrodes. The rates of all three events were selectively modulated by auditory and electrical stimuli, pharmacological manipulation, and cold saline application and had small causal co-occurrences. These results suggest that the proper combination of high-resolution microelectrodes and analytic techniques can capture neuronal dynamics that lay between somatic action potentials and aggregate population activity. Understanding intermediate microscale dynamics in relation to single-cell and network dynamics may reveal important details about activity in the full cortical circuit.
Assuntos
Córtex Cerebral/fisiologia , Neurônios/fisiologia , Estimulação Acústica , Adulto , Animais , Estimulação Elétrica , Eletroencefalografia , Fenômenos Eletrofisiológicos , Epilepsia/fisiopatologia , Espaço Extracelular/fisiologia , Feminino , Humanos , Macaca mulatta , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Microeletrodos , Pessoa de Meia-Idade , Córtex Somatossensorial/fisiologia , Análise de Ondaletas , Adulto JovemRESUMO
Purpose: Neurons carry electrical signals and communicate via electrical activities. The therapeutic potential of electrical stimulation (ES) for the nervous system, including the retina, through improvement of cell survival and function has been noted. Here we investigated the neuroprotective and regenerative potential of ES in a mouse model of inherited retinal degeneration. Methods: Rhodopsin-deficient (Rho-/-) mice received one or two sessions of transpalpebral ES or sham treatments for 7 consecutive days. Intraperitoneal injection of 5-ethynyl-2'-deoxyuridine was used to label proliferating cells. Weekly electroretinograms were performed to monitor retinal function. Retinal morphology, photoreceptor survival, and regeneration were evaluated in vivo using immunohistochemistry and genetic fate-mapping techniques. Müller cell (MC) cultures were employed to further define the optimal conditions of ES application. Results: Noninvasive transpalpebral ES in Rho-/- mice improved photoreceptor survival and electroretinography function in vivo. ES also triggered residential retinal progenitor-like cells such as MCs to reenter the cell cycle, possibly producing new photoreceptors, as shown by immunohistochemistry and genetic fate-mapping techniques. ES directly stimulated cell proliferation and the expression of progenitor cell markers in MC cultures, at least partially through bFGF signaling. Conclusions: Our study showed that transpalpebral ES improved photoreceptor survival and retinal function and induced the proliferation, probably photoreceptor regeneration, of MCs; this occurs via stimulation of the bFGF pathways. These results suggest the exciting possibility of applying noninvasive ES as a versatile tool for preventing photoreceptor loss and mobilizing endogenous progenitors for reversing vision loss in patients with photoreceptor degeneration.
Assuntos
Modelos Animais de Doenças , Terapia por Estimulação Elétrica , Células Fotorreceptoras de Vertebrados/citologia , Degeneração Retiniana/terapia , Células Ganglionares da Retina/fisiologia , Animais , Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Eletrorretinografia , Células Ependimogliais , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Knockout , Degeneração Retiniana/genética , Degeneração Retiniana/fisiopatologia , Rodopsina/genéticaRESUMO
This comprehensive Review focuses on the key challenges and recent progress regarding sodium-metal anodes employed in sodium-metal batteries (SMBs). The metal anode is the essential component of emerging energy storage systems such as sodium sulfur and sodium selenium, which are discussed as example full-cell applications. We begin with a description of the differences in the chemical and physical properties of Na metal versus the oft-studied Li metal, and a corresponding discussion regarding the number of ways in which Na does not follow Li-inherited paradigms in its electrochemical behavior. We detail the major challenges for Na-metal systems that at this time limit the feasibility of SMBs. The core Na anode problems are the following interrelated degradation mechanisms: An unstable solid electrolyte interphase with most organic electrolytes, "mossy" and "lath-like" metal dendrite growth for liquid systems, poor Coulombic efficiency, and gas evolution. Even solid-state Na batteries are not immune, with metal dendrites being reported. The solutions may be subdivided into the following interrelated taxonomy: Improved electrolytes and electrolyte additives tailored for Na-metal anodes, interfacial engineering between the metal and the liquid or solid electrolyte, electrode architectures that both reduce the current density during plating-stripping and serve as effective hosts that shield the Na metal from excessive reactions, and alloy design to tune the bulk properties of the metal per se. For instance, stable plating-stripping of Na is extremely difficult with conventional carbonate solvents but has been reported with ethers and glymes. Solid-state electrolytes (SSEs) such as beta-alumina solid electrolyte (BASE), sodium superionic conductor (NASICON), and sodium thiophosphate (75Na2S·25P2S5) present highly exciting opportunities for SMBs that avoid the dangers of flammable liquids. Even SSEs are not immune to dendrites, however, which grow through the defects in the bulk pellet, but may be controlled through interfacial energy modification. We conclude with a discussion of the key research areas that we feel are the most fruitful for further pursuit. In our opinion, greatly improved understanding and control of the SEI structure is the key to cycling stability. A holistic approach involving complementary post-mortem, in situ, and operando analyses to elucidate full battery cell level structure-performance relations is advocated.
Assuntos
Fontes de Energia Elétrica , Técnicas Eletroquímicas/instrumentação , Sódio/química , Técnicas Eletroquímicas/métodos , EletrodosRESUMO
Magnetic nanoparticle-conjugated polymeric micelles (MNP-PMs) consisting of poly(ethylene glycol)-poly(lactide) (PEG-PLA) and iron oxide nanoparticles were prepared and used as nanocarriers for combined hyperthermia and chemotherapy. Doxorubicin (DOX) was encapsulated in MNP-PMs, and an alternating magnetic field (AMF) resulted in an increase to temperature within a suitable range for inducing hyperthermia and a higher rate of drug release than observed without AMF. In vitro cytotoxicity and hyperthermia experiments were carried out using human lung adenocarcinoma A549 cells. When MNP-PMs encapsulated with an anticancer drug were used to treat A549 cells in combination with hyperthermia under AMF, 78% of the cells were killed by the double effects of heat and the drug, and the combination was more effective than either chemotherapy or hyperthermia treatment alone. Therefore, MNP-PMs encapsulated with an anticancer drug show potential for combined chemotherapy and hyperthermia.
Assuntos
Adenocarcinoma/terapia , Hipertermia Induzida , Neoplasias Pulmonares/terapia , Micelas , Nanopartículas/química , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologiaRESUMO
Hydrocarbons found in the environment are typically characterized by gas chromatography (GC). The shape of the GC chromatogram has been used to identify the source of petroleum contamination. However, the conventional practice of simply comparing the peak patterns of source products to those of environmental samples is dependent on the subjective decisions of individual analysts. We have developed and verified a quantitative analytical method for interpreting GC chromatograms to distinguish refined petroleum products in contaminated soils. We found that chromatograms for gasoline, kerosene, and diesel could be divided into three ranges with boundaries at C6, C8, C16, and C26. In addition, the relative peak area (RPA(GC)) of each range, a dimensionless ratio of the peak area within each range to that of the total range (C6-C26), had a unique value for each petroleum product. An identification index for GC chromatograms (ID(GC)), defined as the ratio of RPA(GC) of C8-C16 to that of C16-C26, was able to identify diesel and kerosene sources in samples extracted from artificially contaminated soils even after weathering. Thus, the ID(GC) can be used to effectively distinguish between refined petroleum products in contaminated soils.
Assuntos
Cromatografia Gasosa/métodos , Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Poluição por Petróleo/análise , Petróleo/análise , Poluentes do Solo/análise , Monitoramento Ambiental/instrumentação , Gasolina/análise , Solo/químicaRESUMO
OBJECTIVE: Programmed death-ligand 1 (PD-L1) has been shown to negatively regulate immune responses via its interaction with PD-1 receptor. In this study, we investigated the effects of PD-L1-Fc treatment on intestinal inflammation using two murine models of inflammatory colitis induced by dextran sulfate sodium (DSS) and T-cell transfer. DESIGN: The anti-colitis effect of adenovirus expressing Fc-conjugated PD-L1 (Ad/PD-L1-Fc) and recombinant PD-L1-Fc protein was evaluated in DSS-treated wild-type and Rag-1 knockout (KO) mice. We examined differentiation of T-helper cells, frequency of innate immune cells, and cytokine production by dendritic cells (DCs) in the colon from DSS-treated mice after PD-L1-Fc administration. In Rag-1 KO mice reconstituted with CD4 CD45RB(high) T cells, we assessed the treatment effect of PD-L1-Fc protein on the development of colitis. RESULTS: Administration of Ad/PD-L1-Fc significantly ameliorated DSS-induced colitis, which was accompanied by diminished frequency of interleukin (IL)-17A-producing CD4 T cells and increased interferon-γ-producing CD4 T cells in the colon of DSS-fed mice. The anti-colitic effect of PD-L1-Fc treatment was also observed in DSS-treated Rag-1 KO mice, indicating lymphoid cell independency. PD-L1-Fc modulated cytokine production by colonic DCs and the effect was dependent on PD-1 expression. Furthermore, PD-L1-Fc protein could significantly reduce the severity of colitis in CD4 CD45RB(high) T-cell-transferred Rag-1 KO mice. CONCLUSIONS: Based on the protective effect of PD-L1-Fc against DSS-induced and T-cell-induced colitis, our results suggest that PD-1-mediated inhibitory signals have a crucial role in limiting the development of colonic inflammation. This implicates that PD-L1-Fc may provide a novel therapeutic approach to treat inflammatory bowel disease.
Assuntos
Antígeno B7-H1/uso terapêutico , Colite Ulcerativa/prevenção & controle , Fatores Imunológicos/uso terapêutico , Doença Aguda , Adenoviridae/genética , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Antígeno B7-H1/farmacologia , Diferenciação Celular/efeitos dos fármacos , Colite Ulcerativa/etiologia , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Colo/imunologia , Citocinas/biossíntese , Células Dendríticas/imunologia , Sulfato de Dextrana , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Vetores Genéticos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Imunidade Inata , Imunidade nas Mucosas , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/metabolismo , Fragmentos Fc das Imunoglobulinas/farmacologia , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Fatores Imunológicos/genética , Fatores Imunológicos/metabolismo , Fatores Imunológicos/farmacologia , Mucosa Intestinal/imunologia , Transfusão de Linfócitos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Linfócitos T Auxiliares-Indutores/imunologia , Células Th17/imunologiaRESUMO
BACKGROUND: Rifabutin has been known to be effective in multidrug-resistant Helicobacter pylori-harboring patients undergoing treatment failure for H. pylori infection. AIM: To evaluate the efficacy of 7-day treatment regimen consisting rifabutin daily but increasing the dose of amoxicillin and lansoprazole in patients who have failed first and second eradication and to assess the side effect profiles in South Korea. METHODS: From December 2007 to May 2013, 59 H. pylori-infected patients with two previous eradication failures were enrolled for this study prospectively. The eligible patients were randomly assigned to either group A or B. Group A received lansoprazole 30 mg bid, amoxicillin 1.0 g tid and rifabutin 150 mg bid during 7 days, whereas group B received lansoprazole 60 mg bid, amoxicillin 1.0 g tid and rifabutin 150 mg bid during 7 days. RESULTS: In group A, H. pylori eradication was achieved in 25 (78.1%) of the 32 patients in the ITT analysis and in 25 (80.6%) of the 31 patients in the PP analysis. In group B, H. pylori eradication was achieved in 26 (96.3%) of the 27 patients in the ITT analysis and in 27 (100%) of the 26 patients in the PP analysis. There was statistically significant difference between the two groups in terms of the eradication rates in PP analysis (p = .047), whereas a marginally statistical significance was found in terms of the eradication rates in ITT analysis (p = .051). Reported side effects were mild, and treatment was well tolerated. No major changes in physical examination or in standard laboratory parameters were observed after treatment. CONCLUSIONS: Rifabutin-based high-dose proton-pump inhibitor (PPI)-combined therapy as empirical rescue treatment is more effective than standard dose PPI-combined rifabutin-based therapy, safe and best tolerable in third-line therapy in the Korean population. The key to successful rescue therapy with rifabutin-amoxicillin-PPI regimen may be to increase doses of PPI.
Assuntos
Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Inibidores da Bomba de Prótons/administração & dosagem , Rifabutina/administração & dosagem , Adulto , Idoso , Amoxicilina/efeitos adversos , Antibacterianos/efeitos adversos , Esquema de Medicação , Farmacorresistência Bacteriana , Quimioterapia Combinada/efeitos adversos , Feminino , Infecções por Helicobacter/microbiologia , Helicobacter pylori/fisiologia , Humanos , Masculino , Estudos Prospectivos , Inibidores da Bomba de Prótons/efeitos adversos , República da Coreia , Rifabutina/efeitos adversos , Resultado do TratamentoRESUMO
Electrical stimulation is currently used to treat a wide range of cardiovascular, sensory and neurological diseases. Despite its success, there are significant limitations to its application, including incompatibility with magnetic resonance imaging, limited control of electric fields and decreased performance associated with tissue inflammation. Magnetic stimulation overcomes these limitations but existing devices (that is, transcranial magnetic stimulation) are large, reducing their translation to chronic applications. In addition, existing devices are not effective for deeper, sub-cortical targets. Here we demonstrate that sub-millimeter coils can activate neuronal tissue. Interestingly, the results of both modelling and physiological experiments suggest that different spatial orientations of the coils relative to the neuronal tissue can be used to generate specific neural responses. These results raise the possibility that micro-magnetic stimulation coils, small enough to be implanted within the brain parenchyma, may prove to be an effective alternative to existing stimulation devices.
Assuntos
Estimulação Elétrica , Magnetoterapia/métodos , Magnetismo , Humanos , Modelos Teóricos , Neurônios/metabolismo , Estimulação Magnética TranscranianaRESUMO
Here we report a case of central retinal artery occlusion after chiropractic manipulation on the neck. A 49-year old man presented at the hospital because of sudden visual loss in his right eye after chiropractic neck manipulation. He had received chiropractic manipulation of the neck by a chiropractor eight days prior. When he first visited us, his best corrected visual acuity in his right eye was hand motion. A full ophthalmic examination was performed. There was cherry-red spot in the macula in his right eye. We performed a fluorescein angiogram and cervical color Doppler. The arterio-venous transit time in the fluorescein angiogram was delayed, and we detected stenosis of the right internal carotid artery with diffuse atherosclerotic plaques in the right common carotid artery. We prescribed ginko biloba extract (Tanamin). Three years after his first visit, the best corrected visual acuity of his right eye was 20 / 200.
Assuntos
Manipulação Quiroprática/efeitos adversos , Oclusão da Artéria Retiniana/etiologia , Transtornos da Visão/etiologia , Doenças das Artérias Carótidas/diagnóstico por imagem , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço/irrigação sanguínea , Oclusão da Artéria Retiniana/diagnóstico , Ultrassonografia , Transtornos da Visão/diagnósticoRESUMO
Myostracum, which is connected from the umbo to the edge of a scar, is not a single layer composed of prismatic layers, but a hierarchically complex multilayered shape composed of minerals and an organic matrix. Through the analysis of the secondary structure, the results revealed that a ß-antiparallel structure was predominant in the mineral phase interface between the myostracum (aragonite) and bottom folia (calcite). After the complete decalcification and deproteinization, the membrane obtained from the interface between the myostracum buried in upper folia, and the bottom folia was identified as chitin. The transitional zone in the interface between the adductor muscle scar and folia are verified. The myostracum disappeared at the edge of the scar of the posterior side. From this study, the entire structure of the myostracum from the adult oyster shell of Crassostrea gigas could be proposed.
RESUMO
Lindera obtusiloba is a medical herb traditionally used in Asia for the improvement of blood circulation, treatment of inflammation, and prevention of liver damage. The possibility that L. obtusiloba affects vascular reactivity remains to be examined. Therefore, the aim of the present study was to evaluate both the in vitro and in vivo vascular effects of an ethanolic extract of L. obtusiloba stems (LOE). Vascular reactivity was assessed in organ chambers using rat aortic rings and the activation of endothelial NO synthase (eNOS) in cultured bovine aortic endothelial cells. LOE induced endothelium-dependent relaxations, which were abolished by inhibitors of nitric oxide synthase (N (ω)-nitro-L: -arginine) and guanylyl cyclase (1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-L-one), significantly reduced by inhibitors of PI3 kinase (wortmannin and LY294002), and not affected by inhibitors of cyclooxygenase (indomethacin) and endothelium-derived hyperpolarizing factor-mediated responses (charybdotoxin plus apamin). LOE prevented contractile responses to phenylephrine and angiotensin II in rings with endothelium, but not in those without endothelium. LOE caused a concentration-dependent phosphorylation of Akt at Serine473 and eNOS at Serine1177 in endothelial cells. Thereafter, the vasoprotective effect of LOE was investigated in an experimental model of hypertension in rats. Intake of LOE prevented the angiotensin II-induced increase in systolic blood pressure, and endothelial dysfunction to acetylcholine and oxidative stress as assessed using dihydroethidine in aortic rings. The present findings indicate that LOE has vasoprotective and antihypertensive properties most likely by stimulating the endothelial formation of NO and inhibiting oxidative stress.
Assuntos
Endotélio Vascular/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Lindera/química , Extratos Vegetais/farmacologia , Angiotensina II/administração & dosagem , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Bovinos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Etanol/química , Hipertensão/fisiopatologia , Masculino , Medicina Tradicional do Leste Asiático , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Caules de Planta , Ratos , Ratos Sprague-DawleyRESUMO
Lysimachia clethroides is widely used in traditional herbal medicine for many purposes, especially for blood vessel-related diseases in Korea and East Asia. Experiments were undertaken to determine whether hydro-alcoholic extract obtained from L. clethroides (LCE) has vasorelaxant activity in the rat aorta rings and, if so, to elucidate the underlying mechanism. Rat aorta rings were suspended in organ chambers for the measurement of changes in isometric tension in the presence or absence of several inhibitors. LCE induced endothelium-dependent vasodilation (ED50 = 6.1 mug/mL) and that was abolished by nitric oxide synthase inhibitor, N-nitro-L-arginine, and guanylyl cyclase inhibitor, 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one, PI3-kinase inhibitor, wortmannin, and cell permeable superoxide dismutase. In addition, LCE decreased vessels contraction by phenylephrine. Prostaglandin synthesis inhibitor, indometacin, and inhibitors of endothelium-derived hyperpolarizing factor, charybdotoxin plus apamin, did not affect vasodilatory effect of LCE. In cultured endothelial cells, LCE-induced phosphorylation of serine 1177-endothelial nitric oxide synthase and serine 473-Akt. LCE inhibited strongly nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity in smooth muscle cells and angiotensin II-induced contraction of rat aorta. Finally, increased oxidative stress in rat aorta-induced by angiotensin II is ameliorated by LCE. Taken together, LCE induces an endothelium-dependent vasodilation and might be involved, at least in part, the activation of the nitric oxide-cyclic guanosine monophosphate pathway. In addition, LCE decreases oxidative stress in aorta by inhibition of NADPH oxidase activity. The present findings indicate that LCE could be a candidate of herbal medicine for cardiovascular diseases associated with disturbed NO production and endothelial dysfunction.
Assuntos
Aorta/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Primulaceae/química , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Aorta/enzimologia , Bovinos , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Endotélio Vascular/enzimologia , Técnicas In Vitro , Masculino , Medicina Tradicional Coreana , NADPH Oxidases/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Extratos Vegetais/isolamento & purificação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Vasodilatadores/isolamento & purificaçãoRESUMO
Soluble protein (MPSP, myostracal prism soluble protein) obtained from myostracum in oyster shell (Crassostrea gigas) was characterized using biochemical and molecular biological techniques. From an analysis of secondary protein structure, it was shown that beta-structure was predominant in MPSP. And via in vitro assays, the relation of MPSP to biomineral phase and morphology was studied. SDS-PAGE revealed one major protein band of 20 kDa. An amino acid sequence of 160 amino acids was deduced for myostracum by characterization of the complementary DNA encoding the protein. The deduced protein was composed of a high proportion of Gly and Asp, typifying a calcium-binding protein for shell formation, and a relatively high proportion of Val, Ala and Ile, typifying an adhesive protein. In contrast to prevailing expectations, (Gly-Asp)n-type sequence motifs exist in MPSP, demanding a revision of previous theories of protein-mineral interactions. The cDNA sequence of myostracum is elucidated for the first time.