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1.
BMC Musculoskelet Disord ; 25(1): 3, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166774

RESUMO

BACKGROUND: The therapeutic efficacy of renin-angiotensin system inhibitors (RASi) in elderly patients with hypertension and at risk of fractures has been in the limelight because of accumulating evidence that localized RAS activation in bone tissue leads to osteoclastic bone resorption, resulting in osteoporosis. This study set out to investigate the association between RASi use and fracture incidence in a large cohort. METHODS: We employed a nested case-control design to investigate the association between RASi use and newly developed fractures. A case was defined as a patient newly diagnosed with a fracture between January 2004 and December 2015. We selected 1,049 cases and controls using 1:1 propensity score matching. Conditional logistic regression analysis was conducted to estimate the association between RASi exposure and fracture incidence. RESULTS: Overall, RASi usage was significantly associated with lower odds for fracture incidence (ever-users vs never-users: OR, 0.73; 95% CI, 0.59-0.91). We found that ARB-only users experienced fewer fractures than RASi-never users (OR, 0.65; 95% CI, 0.49-0.86), whereas ACEi-only users or ARB/ACEi-ever users did not. In subgroup analysis, RASi-ever users without cerebrovascular disease, those with a BMI exceeding 23, and statin exposure had significantly lower ORs. CONCLUSIONS: The present study established a significant association between RASi use and reduced fracture incidence, thus highlighting the potential clinical utility of RASi use as a preventive strategy in elderly patients at risk for osteoporotic fractures.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Fraturas por Osteoporose , Humanos , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Sistema Renina-Angiotensina , Antagonistas de Receptores de Angiotensina/efeitos adversos , Estudos de Casos e Controles , Fraturas por Osteoporose/induzido quimicamente , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle
2.
BMC Med Educ ; 23(1): 231, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37041575

RESUMO

BACKGROUND: The assessment of pharmacy students' readiness to begin the education of an advanced pharmacy practice experience (APPE) in clinical pharmacy settings continues to gain increasing attention. This study aimed to develop an objective structured clinical examination (OSCE) in the core domains acquired through an introductory pharmacy practice experience (IPPE), for evaluating its appropriateness as a tool of assessing clinical pharmacist competency for APPEs in Korean pharmacy students throughout a pilot study. METHODS: OSCE's core competency domains and case scenarios were developed through a literature review, ideation by researchers, and external experts' consensus by a Delphi method. A prospective single-arm pilot test was conducted to implement the OSCE for Korean pharmacy students who completed a 60-h course of in-class simulation IPPE. Their competencies were assessed by four assessors in each OSCE station with a pass-fail grading system accompanied by a scoring rubric. RESULTS: OSCE competency areas including patient counseling, provision of drug information, over-the-counter (OTC) counseling, and pharmaceutical care services were developed with four interactive and one non-interactive cases. Twenty pharmacy students participated in the OSCE pilot test, and their competencies were evaluated by 20 assessors. The performance rate was the lowest in the area of patient counseling for a respiratory inhaler (32.1%) and the highest (79.7%) in OTC counseling for constipation. The students had an average performance rate of 60.4% in their communication skills. Most participants agreed on the appropriateness, necessity, and effectiveness of the OSCE in evaluating pharmacy students' clinical performance and communication skills. CONCLUSIONS: The OSCE model can be used to assess pharmacy students' readiness for off-campus clinical pharmacy practice experience. Our pilot study suggests the necessity of conducting an OSCE domain-based adjustment of difficulty levels, and strengthening simulation-based IPPE education.


Assuntos
Serviço de Farmácia Hospitalar , Farmácia , Estudantes de Farmácia , Humanos , Projetos Piloto , Estudos Prospectivos , Avaliação Educacional/métodos
3.
BMC Med Educ ; 23(1): 560, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37559039

RESUMO

BACKGROUND: An effective test mechanism to evaluate clinical knowledge and skills of the entry-level healthcare professionals is important for providing clinical competency and improving patient care. This study aimed to develop novel, innovative computer-based test (Inno-CBT) item types for application in the national examination of Korean healthcare professionals. METHODS: This exploratory study was conducted from May 2021 to March 2022 by a team of faculty members from pharmacy schools in South Korea. A literature search using PubMed, Google Scholar, RISS, Web of Science, and KoreaMed was performed. Forum presentations, media articles, and previous reports by the Korea Health Personnel Licensing Examination Institute (KHPLEI) were included. Workshops were held, information and ideas were collected and conceptualized, and item types were designed, drafted, and refined. By repeating this process, the Inno-CBT item types were finalized. RESULTS: Forty-one Inno-CBT item types with 28 subtypes were developed. New digital technologies, such as a reactive responsive media interface, an animation insertion, multimedia embedding, and network surfing, were utilized in these novel types. It was anticipated that these Inno-CBT item types would effectively measure abilities in healthcare knowledge, problem-solving skills, and professional behaviors. Some potential barriers to implementing the Inno-CBT item types include item difficulty, operational unfamiliarity, complexity in scoring protocols, and network security. CONCLUSIONS: A variety of styles of novel Inno-CBT item types were developed to evaluate the multifaceted and in-depth professional abilities required for healthcare professionals. Prior to implementing these item types in the national examination, item validation and technical support should be conducted.


Assuntos
Pessoal de Saúde , Licenciamento , Humanos , República da Coreia , Docentes , Computadores
4.
FASEB J ; 34(2): 2451-2464, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31908078

RESUMO

Cellular senescence acts as an important barrier to tumorigenesis by eliminating precancerous cells. Previous studies have shown an essential role of the tumor suppressor p53 in cellular senescence, but how p53 induces cellular senescence is not fully understood. We found that p53 promoted the formation of highly interconnected and elongated mitochondria prior to the onset of cellular senescence. The inhibition of mitochondrial elongation upon p53 expression suppressed cellular senescence, suggesting that mitochondrial elongation is required for the induction of p53-dependent senescence. p53-induced mitochondrial elongation resulted in mitochondrial dysfunction and subsequent increases in intracellular reactive oxygen species (ROS) levels, an important mediator of cellular senescence. Mechanistically, the inhibitory phosphorylation of Drp1 Ser637 increased upon p53 expression, suppressing the translocation of Drp1 into mitochondria. The transcriptional function of p53 was crucial for controlling the inhibitory phosphorylation of Drp1, whereas p21 was nonessential. Protein kinase A (PKA) activity was responsible for p53-mediated Drp1 Ser637 phosphorylation and mitochondrial dysfunction. Taken together, these results suggest that p53 regulates mitochondrial dynamics through the PKA-Drp1 pathway to induce cellular senescence.


Assuntos
Senescência Celular , Dinaminas/metabolismo , Mitocôndrias/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular , Dinaminas/genética , Mitocôndrias/genética , Mitocôndrias/patologia , Fosforilação , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética
5.
Mar Drugs ; 19(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804171

RESUMO

The proteolytic processing of amyloid precursor protein (APP) by ß-secretase (BACE1) and γ-secretase releases amyloid-ß peptide (Aß), which deposits in amyloid plaques and contributes to the initial causative events of Alzheimer's disease (AD). In the present study, the regulatory mechanism of APP processing of three phlorotannins was elucidated in Swedish mutant APP overexpressed N2a (SweAPP N2a) cells. Among the tested compounds, dieckol exhibited the highest inhibitory effect on both intra- and extracellular Aß accumulation. In addition, dieckol regulated the APP processing enzymes, such as α-secretase (ADAM10), ß-secretase, and γ-secretase, presenilin-1 (PS1), and their proteolytic products, sAPPα and sAPPß, implying that the compound acts on both the amyloidogenic and non-amyloidogenic pathways. In addition, dieckol increased the phosphorylation of protein kinase B (Akt) at Ser473 and GSK-3ß at Ser9, suggesting dieckol induced the activation of Akt, which phosphorylated GSK-3ß. The specific phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 triggered GSK-3ß activation and Aß expression. In addition, co-treatment with LY294002 noticeably blocked the effect of dieckol on Aß production, demonstrating that dieckol promoted the PI3K/Akt signaling pathway, which in turn inactivated GSK-3ß, resulting in the reduction in Aß levels.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Benzofuranos/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/fisiopatologia , Animais , Linhagem Celular , Cromonas/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Taninos/farmacologia
6.
FASEB J ; 33(9): 9742-9751, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31120803

RESUMO

Mitophagy has been implicated in mitochondrial quality control and in various human diseases. However, the study of in vivo mitophagy remains limited. We previously explored in vivo mitophagy using a transgenic mouse expressing the mitochondria-targeted fluorescent protein Keima (mt-Keima). Here, we generated mt-Keima Drosophila to extend our efforts to study mitophagy in vivo. A series of experiments confirmed that mitophagy can be faithfully and quantitatively measured in mt-Keima Drosophila. We also showed that alterations in mitophagy upon environmental and genetic perturbation can be measured in mt-Keima Drosophila. Analysis of different tissues revealed a variation in basal mitophagy levels in Drosophila tissues. In addition, we found a significant increase in mitophagy levels during Drosophila embryogenesis. Importantly, loss-of-function genetic analysis demonstrated that the phosphatase and tensin homolog-induced putative kinase 1 (PINK1)-Parkin pathway is essential for the induction of mitophagy in vivo in response to hypoxic exposure and rotenone treatment. These studies showed that the mt-Keima Drosophila system is a useful tool for understanding the role and molecular mechanism of mitophagy in vivo. In addition, we demonstrated the essential role of the PINK1-Parkin pathway in mitophagy induction in response to mitochondrial dysfunction.-Kim, Y. Y., Um, J.-H., Yoon, J.-H., Kim, H., Lee, D.-Y., Lee, Y. J., Jee, H. J., Kim, Y. M., Jang, J. S., Jang, Y.-G., Chung, J., Park, H. T., Finkel, T., Koh, H., Yun, J. Assessment of mitophagy in mt-Keima Drosophila revealed an essential role of the PINK1-Parkin pathway in mitophagy induction in vivo.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Mitofagia/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica , Genótipo , Proteínas Serina-Treonina Quinases/genética , Ubiquitina-Proteína Ligases/genética
7.
Molecules ; 25(21)2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33147823

RESUMO

Amyloid beta (Aß) peptide, one of the most important pathogenic traits of Alzheimer's disease (AD), invokes a cascade of oxidative damage and eventually leads to neuronal death. In the present study, baicalein, wogonin, and oroxylin A, main active flavones in Scutellaria baicalensis, were evaluated for their neuroprotective effects against Aß25-35-stimulated damage. All tested compounds decreased Aß25-35-induced ROS generation and cell cycle arrest. In particular, baicalein exhibited the strongest antioxidant activity. In addition, these compounds suppressed apoptosis by attenuating mitochondrial dysfunction such as loss of membrane potential, Ca2+ accumulation and Bax/Bcl-2 ratio. Furthermore, all tested flavones inhibited the expression of iNOS and COX-2, which resulted in suppressing inflammatory cytokines including TNF-α, NO, and PGE2. Noticeably, all compounds exhibited the anti-inflammatory effects through downregulating NF-κB/MAPK pathway. Especially, oroxylin A was effective against both p65 and IκBα, while wogonin and baicalein were suppressed phospho-p65 and phospho-IκBα, respectively. Taken together, baicalein, wogonin, and oroxylin A can effectively relieve Aß25-35-stimulated neuronal apoptosis and inflammation in PC12 cells via downregulating NF-κB/MAPK signaling pathway.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Flavanonas/farmacologia , Flavonoides/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , NF-kappa B/metabolismo , Células PC12 , Ratos
8.
Biochem Biophys Res Commun ; 483(1): 449-455, 2017 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-28011266

RESUMO

Rebamipide, an amino acid derivative of 2(1H)-quinolinone, has been used for mucosal protection, healing of gastroduodenal ulcers, and treatment of gastritis. Induction of cyclooxygenase (COX)-2, a gastric mucosal protective factor, by rebamipide has been suggested as the major mechanism of the drug action. However, how rebamipide induces COX-2 at the molecular level needs further investigation. In this study, the molecular mechanism underlying the induction of COX-2 by rebamipide was investigated. In gastric carcinoma cells and macrophage cells, rebamipide induced phosphorylation of AMP-activated protein kinase (AMPK), leading to phosphorylation of acetyl-CoA carboxylase (ACC), a substrate of AMPK. The induction of COX-2 by rebamipide was dependent on AMPK activation because compound C, an AMPK inhibitor, abolished COX-2 induction by rebamipide. In a mouse ulcer model, rebamipide protected against hydrochloric acid/ethanol-induced gastric ulcer, and these protective effects were deterred by co-administration of compound C. In parallel, in the gastric tissues, rebamipide increased the phosphorylation AMPK, whereas compound C reduced the levels of COX-2 and phosphorylated ACC, which were increased by rebamipide. Taken together, the activation of AMPK by rebamipide may be a molecular mechanism that contributes to induction of COX-2, probably resulting in protection against gastric ulcers.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Alanina/análogos & derivados , Antiulcerosos/farmacologia , Quinolonas/farmacologia , Alanina/farmacologia , Animais , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Ativação Enzimática/efeitos dos fármacos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Masculino , Camundongos Endogâmicos ICR , Úlcera Gástrica/tratamento farmacológico
9.
Int J Clin Pharmacol Ther ; 55(11): 866-874, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28853698

RESUMO

OBJECTIVE: Drug therapy plays a critical role in most chronic diseases. Effectiveness of pharmaceutical care services in the improvement of clinical, social, or economic outcomes has been scientifically proven through numerous studies. In South Korea, to optimize and standardize pharmaceutical care for patients with chronic metabolic diseases, the development of a pharmaceutical care service model is needed. MATERIALS: To determine the priority of diseases in developing pharmaceutical care service models, analytic hierarchny process (AHP)analysis was used. A survey questionnaire standardized with detailed evaluation areas and an index, to ensure sufficient understanding and identical standards of evaluators, was designed. It was prepared for pair-wise comparisons of individual criteria of candidate diseases. METHODS: Medical specialists and pharmacists who have clinical experience and expertise in chronic metabolic diseases or at least 10 years of experience in pharmacy practice were recruited. They responded to a survey consisting of nine sections by using the pair-wise comparison method. RESULTS: A total of seven candidate diseases were selected for prioritization. Diabetes mellitus was given the highest score of 0.2695, cardiovascular disease (0.2598) being the next, followed by chronic kidney disease (0.2000), and cerebrovascular diseases (0.1087). The criteria were weighted as follows: disease characteristics (0.4964), patient-oriented care (0.3649), and improvement in services (0.1386). CONCLUSION: Diabetes, cardiovascular diseases, and chronic kidney disease were found to have high priority in developing a pharmaceutical care service model in South Korea. In the future, further research for the development and application of pharmaceutical care services models for different types of diseases is required.
.


Assuntos
Modelos Organizacionais , Assistência Farmacêutica/organização & administração , Farmacêuticos/organização & administração , Tratamento Farmacológico , Humanos , República da Coreia , Inquéritos e Questionários
10.
Ecotoxicol Environ Saf ; 126: 147-153, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26748376

RESUMO

The root elongation bioassay is one of the most straightforward test methods used for environmental monitoring in terms of simplicity, rapidity and economy since it merely requires filter paper, distilled water and Petri dishes. However, filter paper as a support material is known to be problematic as it can reduce the sensitivity of the test. The newly developed hydroponic method reported here differs from the conventional root elongation method (US EPA filter paper method) in that no support material is used and the exposure time is shorter (48 h in this test versus 120 h in the US EPA test). For metals, the hydroponic test method was 3.3 (for Hg) to 57 (for Cu) times more sensitive than the US EPA method with the rank orders of sensitivity, estimated from EC50 values, being Cu≥Cd>Ni≥Zn≥Hg for the former and Hg≥Cu≥Ni≥Cd≥Zn for the latter methods. For phenol, the results did not differ significantly; EC50 values were 124 mg L(-1) and 108-180 mg L(-1) for the hydroponic and filter paper methods, respectively. Lettuce was less sensitive than daphnids to wastewaters, but the root elongation response appears to be wastewater-specific and is especially sensitive for detecting the presence of fluorine. The new hydroponic test thus provides many practical advantages, especially in terms of cost and time-effectiveness requiring only a well plate, a small volume of distilled water and short exposure period; furthermore, no specialist expertise is required. The method is simpler than the conventional EPA technique in not using filter paper which can influence the sensitivity of the test. Additionally, plant seeds have a long shelf-life and require little or no maintenance.


Assuntos
Monitoramento Ambiental/métodos , Hidroponia/métodos , Lactuca/efeitos dos fármacos , Metais Pesados/toxicidade , Fenol/toxicidade , Raízes de Plantas/efeitos dos fármacos , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade , Bioensaio/métodos , Lactuca/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Testes de Toxicidade/métodos
11.
Molecules ; 19(11): 18493-510, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25401395

RESUMO

In Korea, soy (Glycine max (L.) Merr.) leaves are eaten as a seasonal vegetable or pickled in soy sauce. Ethyl acetate extracts of soy leaves (EASL) are enriched in pterocarpans and have potent α-glucosidase inhibitory activity. This study investigated the molecular mechanisms underlying the anti-diabetic effect of EASL in C57BL/6J mice with high-fat diet (HFD)-induced type 2 diabetes. Mice were randomly divided into normal diet (ND), HFD (60 kcal% fat diet), EASL (HFD with 0.56% (wt/wt) EASL), and Pinitol (HFD with 0.15% (wt/wt) pinitol) groups. Weight gain and abdominal fat accumulation were significantly suppressed by EASL. Levels of plasma glucose, HbA1c, and insulin in the EASL group were significantly lower than those of the HFD group, and the pancreatic islet of the EASL group had greater size than those of the HFD group. EASL group up-regulated neurogenin 3 (Ngn3), paired box 4 (Pax4), and v-maf musculoaponeurotic fibrosarcoma oncogene homolog A (MafA), which are markers of pancreatic cell development, as well as insulin receptor substrate 1 (IRS1), IRS2, and glucose transporter 4 (GLUT4), which are related to insulin sensitivity. Furthermore, EASL suppressed genes involved in hepatic gluconeogenesis and steatosis. These results suggest that EASL improves plasma glucose and insulin levels in mice with HDF-induced type 2 diabetes by regulating ß-cell proliferation and insulin sensitivity.


Assuntos
Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glycine max/química , Hipoglicemiantes/farmacologia , Células Secretoras de Insulina/metabolismo , Folhas de Planta/química , Pterocarpanos/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Hipoglicemiantes/química , Resistência à Insulina , Células Secretoras de Insulina/patologia , Camundongos , Pterocarpanos/química
12.
Sci Rep ; 14(1): 6714, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509247

RESUMO

The interplay between fatty liver disease (FLD) and metabolic dysfunction has given rise to the concept of metabolic associated fatty liver disease (MAFLD). With vitamin D insufficiency frequently co-occurring with FLD and linked to metabolic abnormalities, this study investigates the potential role of vitamin D in the development of MAFLD. In this cross-sectional analysis, 22,476 participants with baseline metabolic dysfunction and known serum 25-OH-vitamin D3 levels were examined. The fatty liver index (FLI) was utilized to predict FLD, dividing subjects into MAFLD and non-MAFLD groups. Further stratification by vitamin D levels (sufficient vs. insufficient) and gender provided a detailed assessment through binary logistic regression to determine the association of vitamin D status with MAFLD incidence. Vitamin D insufficiency correlated with a higher MAFLD incidence in metabolically impaired individuals. Post-adjustment, the correlation was stronger (men: aOR = 1.32, 95% CI = 1.22-1.43, P < 0.001; women: aOR = 1.53, 95% CI = 1.18-1.98, P = 0.001). Lower serum 25-OH-vitamin D3 levels were found in MAFLD patients across genders (men: P = 0.003; women: P = 0.014), with a higher prevalence of insufficiency in MAFLD cases (men: P = 0.007; women: P = 0.003). The vitamin D-MAFLD link was stable across subgroups and using varying FLI criteria. Our findings indicate a clear association between vitamin D insufficiency and increased MAFLD incidence, underscoring the potential of vitamin D as an anti-lipogenic and anti-fibrotic agent.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Deficiência de Vitamina D , Feminino , Humanos , Masculino , Vitamina D , Estudos Transversais , Vitaminas , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Calcifediol , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia
13.
Biochim Biophys Acta ; 1820(4): 542-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22251576

RESUMO

BACKGROUND: We synthesized (2RS,4R)-2-(2,4-dihydroxyphenyl)thiazolidine-4-carboxylic acid (MHY384) as a potential tyrosinase inhibitor and investigated its antityrosinase activity. METHODS: The structure of MHY384 was established using (1)H and (13)C NMR spectroscopy and mass spectral analyses. To investigate dual mechanisms of action of MHY384 for the inhibition of melanin synthesis, we confirmed the inhibitory effect of tyrosinase catalytic activity of MHY384. Then, we confirmed the inhibitory effect of MHY384 on transcription of tyrosinase mRNA through alpha-MSH-induced cAMP-PKA-MITF signaling. In addition, we supported the inhibitory mechanism of MHY384 against tyrosinase using a kinetic study and docking programs. RESULTS: To determine how MHY384 regulates melanogenesis, we measured melanin levels and expression of the genes for microphthalmia-associated transcription factor (MITF) and tyrosinase in α-melanocyte-stimulating hormone (α-MSH)-induced B16F10 melanoma cells. MHY384 potently inhibited tyrosinase activity and melanin production in B16F10 melanoma cells. Through docking models, we were able to construct the tertiary structure of mushroom tyrosinase and simulate its docking with MHY384. The result supports that MHY384 strongly interacts with tyrosinase residues in the active site and it can directly inhibit tyrosinase. To investigate additional mechanisms of action of MHY384, we confirmed that the inhibition of tyrosinase activity was found to be due to the modulation of the expression of tyrosinase and its transcription factor, MITF, through cAMP, which regulates protein kinase A. CONCLUSIONS: This study strongly indicates that the depigmenting effect of MHY384 results from the down-regulation of MITF and tyrosinase through direct tyrosinase inhibition. GENERAL SIGNIFICANCE: Our findings suggest that MHY384 can be an effective skin-whitening agent.


Assuntos
Melaninas/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/antagonistas & inibidores , Transdução de Sinais , Tiazolidinas/farmacologia , Animais , Domínio Catalítico , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Melaninas/genética , Melanoma/metabolismo , Camundongos , Fator de Transcrição Associado à Microftalmia/genética , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Estrutura Terciária de Proteína , Transdução de Sinais/efeitos dos fármacos , Tiazolidinas/síntese química , Tiazolidinas/química , Tiazolidinas/metabolismo , alfa-MSH/metabolismo
14.
Dig Dis Sci ; 58(5): 1226-34, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23192646

RESUMO

BACKGROUND: Co-administration of a reduction inhibitor and a colon-specific prodrug of a glucocorticoid susceptible to colonic reductive metabolism is suggested as a strategy to circumvent the therapeutic loss of the glucocorticoid delivered to and acting locally at the large intestine. AIMS: We examined whether the strategy was feasible as a pharmacotherapy for treatment of inflammatory bowel disease. METHODS: Glycyrrhizin (GCZ), a reduction inhibitor, was tested for its inhibition of the colonic metabolism of methylprednisolone (MP). Therapeutic activity against TNBS-induced rat colitis and adrenal suppression were compared after oral administration of methylprednisolone 21-sulfate sodium (MPS), a colon-specific prodrug of MP, or MPS/GCZ to colitic rats. RESULTS: Upon incubation of MP with the cecal contents, MP disappeared, and this was delayed by addition of GCZ. In addition, more MP produced from MPS in the cecal contents accumulated in the presence of GCZ. Consistent with these results, upon oral administration of MPS/GCZ, MPS or MP, MP was detected at a greater level in the large intestine for MPS/GCZ. MPS/GCZ ameliorated TNBS-induced colitis of rats, and this therapeutic effect was superior to that of MPS and MP. Moreover, MPS/GCZ decreased the plasma levels of corticosterone and ACTH to a greater extent than MPS, but less than MP. CONCLUSIONS: Co-administration of GCZ, a reduction inhibitor, may be a plausible strategy to reduce the therapeutic loss of MP produced from MPS in the large intestine, thus improving the therapeutic property of the prodrug against inflammatory bowel disease.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Ácido Glicirrízico/uso terapêutico , Metilprednisolona/uso terapêutico , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Anti-Inflamatórios/metabolismo , Colite/metabolismo , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Masculino , Metilprednisolona/metabolismo , Pró-Fármacos/uso terapêutico , Ratos , Ratos Sprague-Dawley
15.
Antioxidants (Basel) ; 12(3)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36978877

RESUMO

Increasing evidence is suggesting that amyloid-ß peptide (Aß), a characteristic of Alzheimer's disease (AD), induces oxidative stress and mitochondrial dysfunction, leading to neuronal death. This study aimed to demonstrate the antioxidant and anti-apoptotic effects of fucoxanthin, a major marine carotenoid found in brown algae, against neuronal injury caused by Aß. Non-toxic dose range of fucoxanthin (0.1-5 µM) were selected for the neuroprotective study against Aß25-35. The PC12 cells were pretreated with different concentrations of fucoxanthin for 1 h before being exposed to 10 µM Aß25-35 for another 24 h. The present results showed that fucoxanthin inhibited Aß25-35-induced cell death by recovering cell cycle arrest and decreasing intracellular reactive oxygen species (ROS) level. The compound enhanced mitochondrial recovery and regulated apoptosis related proteins including B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax) from Aß25-35-induced oxidative stress. Concomitantly, fucoxanthin increased the expression of nuclear factor E2-related factor 2 (Nrf2) and its downstream phase II detoxifying enzymes including NADPH: quinone oxidoreductase-1 (NQO-1), glutamate cysteine ligase modifier subunit (GCLm), and thioredoxin reductase 1 (TrxR1), whereas it decreased the expression of cytoplasmic Kelch-like ECH-associated protein 1 (Keap1). Moreover, pretreatment of fucoxanthin reduced Fyn phosphorylation via protein kinase B (Akt)-mediated inhibition of glycogen synthase kinase-3ß (GSK-3ß), which increased the nuclear localization of Nrf2, suggesting that the compound enhanced Nrf2 expression by the activation of upstream kinase as well as the dissociation of the Nrf2-Keap1 complex. Further validation with a specific phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 demonstrated that the fucoxanthin-mediated Nrf2 antioxidant defense system was directly associated with the Akt/GSK-3ß/Fyn signaling pathway. In silico simulation revealed that the oxygen groups of fucoxanthin participated in potent interactions with target markers in the Nrf2 signaling pathway, which may affect the biological activity of target markers. Taken together, the present results demonstrated that the preventive role of fucoxanthin on Aß-stimulated oxidative injury and apoptosis via Akt/GSK-3ß/Fyn signaling pathway. This study would provide a useful approach for potential intervention for AD prevention.

16.
Biochim Biophys Acta ; 1810(6): 612-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21397665

RESUMO

BACKGROUND: Many tyrosinase inhibitors find application in cosmetics and pharmaceutical products for the prevention of the overproduction of melanin in the epidermis. A series of 5-(substituted benzylidene)hydantoin derivatives 2a-2k were prepared, and their inhibitory activities toward tyrosinase and melanin formation were evaluated. METHODS: The structures of the compounds were established using (1)H and (13)C NMR spectroscopy and mass spectral analyses. All the synthesized compounds were evaluated for their mushroom tyrosinase inhibition activity. RESULTS: The best results were obtained for compound 2e which possessed hydroxyl group at R(2) and methoxy group at R(3), respectively. We predicted the tertiary structure of tyrosinase, simulated its docking with compound 2e and confirmed that this compound interacts strongly with mushroom tyrosinase residues as a competitive tyrosinase inhibitor. In addition, we found that 2e inhibited melanin production and tyrosinase activity in B16 cells. CONCLUSIONS: Compound 2e could be considered as a promising candidate for preclinical drug development in skin hyperpigmentation applications. GENERAL SIGNIFICANCE: This study will enhance understanding of the mechanism of tyrosinase inhibition and will contribute to the development of effective drugs for use hyperpigmentation.


Assuntos
Compostos de Benzilideno/farmacologia , Desenho de Fármacos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Hidantoínas/farmacologia , Melaninas/antagonistas & inibidores , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/química , Sobrevivência Celular , Células Cultivadas , Simulação por Computador , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Hidantoínas/síntese química , Hidantoínas/química , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Melaninas/biossíntese , Modelos Moleculares , Estrutura Molecular
17.
Mol Pharm ; 9(5): 1310-9, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22428658

RESUMO

For the purpose of development of orally active peptide therapeutics targeting NFκB for treatment of inflammatory bowel disease (IBD), two major barriers in oral delivery of therapeutic peptides, metabolic lability and tissue impermeability, were circumvented by introduction of a colon-targeted delivery system and cell permeable peptides (CPP) to NFκB inhibitory peptides (NIP). Suppression of NFκB activation was compared following treatment with various CPP conjugated NIPs (CPP-NIP). The most potent CPP-NIP was loaded in a capsule coated with a colon specific polymer, which was administered orally to colitic rats. The anti-inflammatory activity of the colon-targeted CPP-NIP was evaluated by measuring inflammatory indices in the inflamed colonic tissue. For confirmation of the local action of the CPP-NIP, the same experiment was done after rectal administration. Tissue permeability of the CPP-NIP was examined microscopically and spectrophotometrically using FITC-labeled CPP-NIP (CPP-NIP-FITC). NEMO binding domain peptide (NBD, TALDWSWLQTE) fused with a cell permeable peptide CTP (YGRRARRRARR), CTP-NBD, was most potent in inhibiting NFκB activity in cells. Colon-targeted CTP-NBD, but not colon-targeted NBD and CTP-NBD in an enteric capsule, ameliorated the colonic injury, which was in parallel with decrease in MPO activity and the levels of inflammatory mediators. Intracolonic treatment with CTP-NBD alleviated rat colitis and improved all the inflammatory indicators. CTP-NBD-FITC was detected at much greater level in the inflamed tissue than was NBD-FITC. Taken together, introduction of cell permeability and colon targetability to NIP may be a feasible strategy for an orally active peptide therapy for treatment of IBD.


Assuntos
Peptídeos Penetradores de Células/química , Colo/metabolismo , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/metabolismo , NF-kappa B/antagonistas & inibidores , Peptídeos/química , Peptídeos/uso terapêutico , Administração Oral , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Western Blotting , Células CACO-2 , Linhagem Celular Tumoral , Colo/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Síndrome do Intestino Irritável/induzido quimicamente , Masculino , Ratos , Ácido Trinitrobenzenossulfônico/toxicidade
18.
Biogerontology ; 13(2): 133-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22033706

RESUMO

Baicalin, a herb-derived flavonoid compound, has beneficial activities, including the modulation of oxidative stress and inflammation. Nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ) is a ligand-activated transcription factor that plays an important role in regulating nuclear factor-κB (NF-κB)-induced age-related inflammation. We investigated the anti-inflammatory action of baicalin, which depends on its ability to activate PPARγ, and subsequently to suppress NF-κB. We examined baicalin-treated kidney tissue from 24-month-old Fischer 344 aged rats (10 or 20 mg/kg/day for 10 days) and baicalin-fed mice (10 mg/kg/day for 3 days) for in vivo investigations, and used endothelial YPEN-1 cells for in vitro studies. In the baicalin-fed aged rats, there was a marked enhancement of both nuclear protein levels and DNA binding activity of PPARγ, and a decreased expression of NF-κB target genes (VCAM-1, IL-1ß, and IL-6) compared with non-baicalin-fed aged rats. Furthermore, to confirm the anti-inflammatory action of PPARγ activated by baicalin, we used lipopolysaccharide (LPS)-treated cells and mice. The results showed that baicalin induced PPARγ-selective activation in YPEN-1 cells, and that the effects of baicalin were blocked by the PPARγ receptor antagonist, GW9662. In addition, baicalin treatment prevented RS generation, NF-κB activation and the expression of pro-inflammatory genes, whereas it increased PPARγ expression in LPS-treated cells and mouse kidney. Our data suggest that baicalin-induced PPARγ expression reduced age-related inflammation through blocking pro-inflammatory NF-κB activation. These results indicate that baicalin is a novel PPARγ activator and that this agent may have the potential to minimize inflammation.


Assuntos
Envelhecimento , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Rim/efeitos dos fármacos , NF-kappa B/metabolismo , Nefrite/prevenção & controle , PPAR gama/agonistas , Fatores Etários , Envelhecimento/imunologia , Envelhecimento/metabolismo , Anilidas/farmacologia , Animais , Linhagem Celular , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Mediadores da Inflamação/metabolismo , Rim/imunologia , Rim/metabolismo , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/genética , Nefrite/induzido quimicamente , Nefrite/genética , Nefrite/imunologia , Nefrite/metabolismo , PPAR gama/metabolismo , Ratos , Ratos Endogâmicos F344 , Transfecção , Regulação para Cima
19.
Ann Pharmacother ; 46(9): 1141-51, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22947591

RESUMO

BACKGROUND: Cyclosporine is often used to prevent allograft rejection in renal transplant recipients. However, cyclosporine has a narrow therapeutic window and large variability in its pharmacokinetics. Individual characteristics and genetic polymorphisms can cause the variation. Hence, it is important to determine the cause(s) of the variation in cyclosporine pharmacokinetics. To our knowledge, this is the first reported population pharmacokinetic study of cyclosporine in living donor renal transplant recipients that considered the genetic polymorphism as a covariate. OBJECTIVE: To build a population pharmacokinetic model of cyclosporine in living donor renal transplant recipients and identify covariates including CYP3A5*3, ABCB1 genetic polymorphisms that affect cyclosporine pharmacokinetic parameters. METHODS: Clinical characteristics and cyclosporine concentration data for 69 patients who received cyclosporine-based immunosuppressive therapy after living donor renal transplantation were collected retrospectively for up to 400 postoperative days. CYP3A5*1/*3 and ABCB1C1236T, G2677T/A, C3435T geno-typing was performed. A population pharmacokinetic analysis was conducted using a NONMEM program. After building the final model, 1000 bootstrappings were performed to validate the final model. RESULTS: In total, 2034 blood samples were collected. A 1-compartment open model with first-order absorption and elimination was chosen to describe the pharmacokinetics of cyclosporine. A population pharmacokinetic analysis showed that postoperative days, sex, and CYP3A5 genotype significantly affected the pharmacokinetics of cyclosporine. The final estimate of mean clearance was 56 L/h, and the mean volume of distribution was 4650 L. The interindividual variability for these parameters was 22.98% and 51.48%, respectively. CONCLUSIONS: Using the present model to calculate the dose of cyclosporine with CYP3A5 genotyping can be possible for the patients whose cyclosporine concentration is not within the therapeutic range even with therapeutic drug monitoring.


Assuntos
Ciclosporina/farmacocinética , Citocromo P-450 CYP3A/genética , Imunossupressores/farmacocinética , Modelos Biológicos , Adulto , Ciclosporina/sangue , Ciclosporina/uso terapêutico , Feminino , Genótipo , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/sangue , Imunossupressores/uso terapêutico , Transplante de Rim , Doadores Vivos , Masculino , Polimorfismo Genético
20.
Ann Pharmacother ; 46(12): 1637-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23170032

RESUMO

BACKGROUND: The second-generation serotonin 5-HT(3) receptor antagonist palonosetron has shown improved efficacy in the prevention of both acute and delayed chemotherapy-induced nausea and vomiting (CINV). However, there have been no randomized controlled trials supporting the preferential use of palonosetron in triple antiemetic regimens for patients receiving multiday highly emetogenic chemotherapy (HEC). OBJECTIVE: To compare the effectiveness of palonosetron-based and first-generation 5-HT(3) receptor antagonist-based triple antiemetic regimens in cancer patients receiving multiday HEC. METHODS: This was a review and analysis of medical record data. A total of 115 patients who had received multiday HEC were included and grouped into a palonosetron-based antiemetic group (n = 73) or a first-generation 5-HT(3) receptor antagonist-based antiemetic group (n = 42). Data on CINV were collected in 24-hour intervals for 120 hours after the start of chemotherapy. RESULTS: Complete response rates did not differ significantly between the 2 groups during any of the 3 phases: acute (0-24 hours), p = 0.877; overlap (24-120 hours), p = 0.997; and overall (0-120 hours), p = 0.723. The proportion of patients with complete control was similar between the groups during each phase: acute, p = 0.862; overlap, p = 0.838; and overall, p = 0.828. There was also no significant difference in other end points between the 2 groups. Among all patients, females experienced significantly more acute nausea (p = 0.040) and vomiting (p = 0.046) than males. Compared with nondrinkers, patients who consumed alcohol had a lower overall incidence of vomiting (p = 0.020). CONCLUSIONS: Within a triple antiemetic regimen, a palonosetron-based antiemetic regimen was not significantly different from regimens based on first-generation 5-HT(3) receptor antagonists in preventing CINV during multiday HEC.


Assuntos
Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Isoquinolinas/uso terapêutico , Náusea/prevenção & controle , Quinuclidinas/uso terapêutico , Vômito/prevenção & controle , Adulto , Idoso , Consumo de Bebidas Alcoólicas/epidemiologia , Antieméticos/administração & dosagem , Antineoplásicos/administração & dosagem , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Palonossetrom , Estudos Retrospectivos , Antagonistas do Receptor 5-HT3 de Serotonina/administração & dosagem , Antagonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Fatores Sexuais , Resultado do Tratamento , Vômito/induzido quimicamente
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