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1.
Int J Mol Sci ; 25(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38256022

RESUMO

Our study investigated the embryo-ototoxic effects of deodorant2 (DA2) on zebrafish embryos, which serve as valuable model organisms due to genetic and physiological similarities to humans. We focused on understanding DA2's impact on zebrafish hair cells, which are vital for sensory perception and balance regulation. DA2, provided by the Ministry of Environment, Republic of Korea, was used at 460 µg/mL in dimethyl sulfoxide (DMSO), with a 0.43% DMSO solvent control group. Three experiments, each using 10 zebrafish specimens from each group, showed an initial 13% hair cell count reduction in the DA2-exposed group. Subsequent experiments demonstrated reductions of 37% and 22%, each with one mortality case. Statistical analysis revealed a significant 24% hair cell count reduction in the DA2-exposed group. We also assessed DA2's impact on zebrafish behavior. Although not statistically significant, differences in distances traveled (0.33-0.39, 95% confidence interval: -0.46-1.1, p = 0.2033) and latencies (-0.016-0.018, 95% confidence interval: -0.052-0.021, p = 0.1917) hinted at negative effects. These results highlight DA2's ototoxic properties affecting zebrafish auditory systems and behavior. Further investigation into DA2's effects on aquatic organisms and potential mitigation strategies are essential. These findings contribute to understanding DA2's safety profile, benefiting aquatic ecosystems and human health assessments.


Assuntos
Desodorantes , Ototoxicidade , Perciformes , Humanos , Animais , Dimetil Sulfóxido , Ecossistema , Peixe-Zebra , Embrião de Mamíferos
2.
EMBO Rep ; 22(3): e49804, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33369874

RESUMO

A long-standing problem in biology is how to dissect traits for which no tractable model exists. Here, we screen for genes like the nude locus (Foxn1)-genes central to mammalian hair and thymus development-using animals that never evolved hair, thymi, or Foxn1. Fruit flies are morphologically disrupted by the FOXN1 transcription factor and rescued by weak reductions in fly gene function, revealing molecules that potently synergize with FOXN1 to effect dramatic, chaotic change. Strong synergy/effectivity in flies is expected to reflect strong selection/functionality (purpose) in mammals; the more disruptive a molecular interaction is in alien contexts (flies), the more beneficial it will be in its natural, formative contexts (mammals). The approach identifies Aff4 as the first nude-like locus, as murine AFF4 and FOXN1 cooperatively induce similar cutaneous/thymic phenotypes, similar gene expression programs, and the same step of transcription, pre-initiation complex formation. These AFF4 functions are unexpected, as AFF4 also serves as a scaffold in common transcriptional-elongation complexes. Most likely, the approach works because an interaction's power to disrupt is the inevitable consequence of its selected-for power to benefit.


Assuntos
Fatores de Transcrição Forkhead , Pele , Animais , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica , Camundongos , Camundongos Nus , Fenótipo , Pele/metabolismo , Timo/metabolismo
3.
J Integr Neurosci ; 22(1): 18, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722243

RESUMO

BACKGROUND AND PURPOSE: REM sleep behavior disorder (RBD) in Parkinson's disease (PD) is associated with characteristic clinical subtypes and prognosis. In addition, nigrostriatal pathway, the most vulnerable anatomical area in PD, formed neuronal network interplaying with cortical and subcortical structures, and which may cause PD clinical phenotype. We evaluated the regional selectivity of presynaptic striatal dopaminergic denervation associated with RBD in PD. METHODS: We compared two groups (n = 16) of PD patients with and without RBD in terms of specific binding ratios (SBR) in subregions of the striatum, which were measured using positron emission tomography with 18F-FP-CIT. SBRs of the anterior and posterior caudate, ventral striatum, and posterior and ventral putamen regions were measured in more or less affected side, and right or left side, or bilateral sum of the striatum. RESULTS: Age, disease duration, and severity of parkinsonism were not significantly different between groups. Although group differences in all areas were not significant with multiple comparison corrections, SBR of the ventral striatum and anterior caudate in sum of both sides was significantly less in the RBD than in the non-RBD group without correction (p < 0.05). In the right anterior caudate and left ventral striatum, SBR was also lower in the RBD than in the non-RBD group without correction (p < 0.05). Attention function was impaired in the RBD group compared with the non-RBD group (p < 0.05). However, these statistical significances were not definite after correction of multiple comparisons (p > 0.05). CONCLUSIONS: There is a possibility that RBD in early PD may be associated with presynaptic dopaminergic denervation in the ventral striatum and anterior caudate, which may explain decreased attention in our RBD group. RBD in PD may imply a distinct pathological progression. However, further study using large numbers of participants or longitudinal observation is necessary for the statistical conclusion because of small sample size.


Assuntos
Corpo Estriado , Doença de Parkinson , Transtorno do Comportamento do Sono REM , Humanos , Corpo Estriado/diagnóstico por imagem , Dopamina , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Transtorno do Comportamento do Sono REM/etiologia
4.
Knee Surg Sports Traumatol Arthrosc ; 23(2): 555-61, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23370982

RESUMO

PURPOSE: This study examined the early effect of a subacromial steroid injection on injured rotator cuff tendon. METHODS: Forty rats were allocated into two groups: a steroid injection (group 1) and no injection as control (group 2). A full-thickness defect was made at the unilateral infraspinatus tendon in both groups. A single dose of methylprednisolone was injected in steroid group. The tendon was harvested at 1, 3, 7, 14, and 42 days after surgery; gene expression and immunohistochemical study were performed for type-I/III collagen, tumour necrosis factor (TNF)-α, and extracellular matrix molecules. RESULTS: The type-III to type-I collagen ratio was at 7 days higher in the steroid group than that in the control group and decreased to the control level at 14 days and was maintained until 42 days. The general expression of the MMPs and TIMPs between two groups showed similar pattern regardless of the steroid injection. The gene expression of aggrecan and fibronectin in the steroid group was significantly higher than that in the control group (p < 0.05) at 3 days after surgery. They decreased to the equal level with control group at 7 days after surgery. Both groups showed no significant difference between aggrecan and fibronectin until 42 days after surgery (n.s.). CONCLUSIONS: A subacromial steroid injection may alter the collagen composition and extracellular matrix and interfere with the healing process in an acute tear of rat infraspinatus tendon at the early phase after the injection. However, these alterations seem to become normalized after the early inflammatory healing phase.


Assuntos
Glucocorticoides/administração & dosagem , Metilprednisolona/administração & dosagem , Manguito Rotador/efeitos dos fármacos , Traumatismos dos Tendões/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Animais , Colágeno/metabolismo , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Imuno-Histoquímica , Injeções , Masculino , Ratos , Ratos Sprague-Dawley , Manguito Rotador/metabolismo , Manguito Rotador/fisiopatologia , Lesões do Manguito Rotador , Traumatismos dos Tendões/metabolismo , Traumatismos dos Tendões/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo
5.
BMC Complement Altern Med ; 14: 109, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24666969

RESUMO

BACKGROUND: Activation of the Wnt pathway is known to promote tumorigenesis and tumor metastasis, and targeting Wnt pathway inhibition has emerged as an attractive approach for controlling tumor invasion and metastasis. The major pathway for inhibiting Wnt is through the degradation of ß-catenin by the GSK3-beta/CK1/Axin/APC complex. It was found that Hep3B hepato-carcinoma cells respond to anthocyanins through GSK3-beta-induced suppression of beta-catenin; however, they cannot dephosphorylate GSK3-beta without AMPK activation. METHODS: We tested the effects of anthocyanins on proliferation and apoptosis by MTT and Annexin V-PI staining in vitro. Mouse xenograft models of hepato-carcinomas were established by inoculation with Hep3B cells, and mice were injected with 50 mg/kg/ml of anthocyanins. In addition, protein levels of p-GSK3-beta, beta-catenin, p-AMPK, MMP-9, VEGF, and Ang-1 were also analyzed using western blot. RESULTS: Anthocyanins decrease phospho-GSK3-beta and beta-catenin expression in an in vivo tumor xenograft model, increase AMPK activity in this model, and inhibit cell migration and invasion, possibly by inhibiting MMP-2 (in vitro) and the panendothelial marker, CD31 (in vivo). To elucidate the role of the GSK3-beta/beta-catenin pathway in cancer control, we conditionally inactivated this pathway, using activated AMPK for inhibition. Further, we showed that AMPK siRNA treatment abrogated the ability of anthocyanins to control cell proliferation and metastatic potential, and Compound C, an AMPK inhibitor, could not restore GSK3-beta regulation, as exhibited by anthocyanins in Hep3B cells. CONCLUSION: These observations imply that the AMPK-mediated GSK3-beta/beta-catenin circuit plays crucial roles in inhibiting cancer cell proliferation and metastasis in anthocyanin-treated hepato-carcinoma cells of Meoru origin.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antocianinas/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Neoplasias/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Vitis/química , Animais , Antocianinas/uso terapêutico , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Proliferação de Células , Modelos Animais de Doenças , Frutas/química , Glicogênio Sintase Quinase 3 beta , Humanos , Masculino , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Neoplasias/metabolismo , Neoplasias/patologia , Extratos Vegetais/uso terapêutico , República da Coreia , Transplante Heterólogo , Via de Sinalização Wnt , beta Catenina/metabolismo
6.
Genesis ; 50(11): 783-800, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22611050

RESUMO

Hair follicles are simple, accessible models for many developmental processes. Here, using mutant mice, we show that Bmpr2, a known receptor for bone morphogenetic proteins (Bmps), and Acvr2a, a known receptor for Bmps and activins, are individually redundant but together essential for multiple follicular traits. When Bmpr2/Acvr2a function is reduced in cutaneous epithelium, hair follicles undergo rapid cycles of hair generation and loss. Alopecia results from a failure to terminate hair development properly, as hair clubs never form, and follicular retraction is slowed. Hair regeneration is rapid due to premature activation of new hair-production programs. Hair shafts differentiate aberrantly due to impaired arrest of medullary-cell proliferation. When Bmpr2/Acvr2a function is reduced in melanocytes, gray hair develops, as melanosomes differentiate but fail to grow, resulting in organelle miniaturization. We conclude that Bmpr2 and Acvr2a normally play cell-type-specific, necessary roles in organelle biogenesis and the shutdown of developmental programs and cell division.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo II/fisiologia , Cor de Cabelo , Cabelo/fisiopatologia , Receptores de Activinas Tipo II/deficiência , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/fisiologia , Alopecia/genética , Alopecia/metabolismo , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/deficiência , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Feminino , Cabelo/crescimento & desenvolvimento , Cabelo/patologia , Folículo Piloso/patologia , Masculino , Melanócitos/metabolismo , Melanossomas/metabolismo , Melanossomas/fisiologia , Camundongos , Camundongos Transgênicos , Cultura Primária de Células
7.
Cell Tissue Res ; 347(2): 303-10, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22105920

RESUMO

We compared the bone regeneration potentials of autologous cultured osteoblasts and of bone-marrow-derived autologous MSCs in combination with allogeneic cancellous bone granules in a rabbit radial defect model. Radial shaft defects over 15 mm were made in 26 New Zealand white rabbits. The animals underwent insertion of allogeneic cancellous bone granules containing autologous osteoblasts into right-side defects (the experimental group) and of allogeneic cancellous bone granules with autologous MSCs into left-side defects (the control group). To quantitatively assess bone regeneration, radiographic evaluations as well as BMD and BMC measurements were performed 3, 6, 9 and 12 weeks post-implantation and histology as well as micro-CT image analysis were performed at 6 and 12 weeks. Radiographic evaluations 3 weeks post-implantation showed that the experimental group had a higher mean bone quantity index (p < 0.05) and micro-CT image analysis showed that experimental sides had a greater mean total regenerated bone volume and surface area than the control sides (p < 0.05). Histologic evaluations obtained at 6 and 12 weeks revealed distinctly greater granule resorption and new bone formation in the experimental group. This in vivo study demonstrates that a combination of autologous osteoblasts and small-sized, allogeneic cancellous bone granules leads to more rapid bone regeneration than autologous MSCs and small-sized, allogeneic cancellous bone granules.


Assuntos
Osso e Ossos/metabolismo , Durapatita/metabolismo , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Animais , Regeneração Óssea , Osso e Ossos/cirurgia , Osso e Ossos/ultraestrutura , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Masculino , Osteoblastos/metabolismo , Coelhos , Engenharia Tecidual/métodos , Transplante Autólogo , Transplante Homólogo , Microtomografia por Raio-X
8.
Mol Metab ; 66: 101618, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36283677

RESUMO

OBJECTIVES: Insulin treatment remains the sole effective intervention for Type 1 Diabetes. Here, we investigated the therapeutic potential of converting intestinal epithelial cells to insulin-producing, glucose-responsive ß-like cells by targeted inhibition of FOXO1. We have previously shown that this can be achieved by genetic ablation in gut Neurogenin3 progenitors, adenoviral or shRNA-mediated inhibition in human gut organoids, and chemical inhibition in Akita mice, a model of insulin-deficient diabetes. METHODS: We profiled two novel FOXO1 inhibitors in reporter gene assays, and hepatocyte gene expression studies, and in vivo pyruvate tolerance test (PTT) for their activity and specificity. We evaluated their glucose-lowering effect in mice rendered insulin-deficient by administration of streptozotocin. RESULTS: We provide evidence that two novel FOXO1 inhibitors, FBT432 and FBT374 have glucose-lowering and gut ß-like cell-inducing properties in mice. FBT432 is also highly effective in combination with a Notch inhibitor in this model. CONCLUSION: The data add to a growing body of evidence suggesting that FOXO1 inhibition be pursued as an alternative treatment to insulin administration in diabetes.


Assuntos
Diabetes Mellitus Experimental , Proteína Forkhead Box O1 , Animais , Camundongos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Proteína Forkhead Box O1/antagonistas & inibidores , Glucose/metabolismo , Insulina/metabolismo , Estreptozocina
9.
Mol Metab ; 66: 101624, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36341906

RESUMO

OBJECTIVE: Lifelong insulin replacement remains the mainstay of type 1 diabetes treatment. Genetic FoxO1 ablation promotes enteroendocrine cell (EECs) conversion into glucose-responsive ß-like cells. Here, we tested whether chemical FoxO1 inhibitors can generate ß-like gut cells. METHODS: We used Ngn3-or Villin-driven FoxO1 ablation to capture the distinctive developmental effects of FoxO1 on EEC pool. We combined FoxO1 ablation with Notch inhibition to enhance the expansion of EEC pool. We tested the ability of an orally available small molecule of FoxO1 inhibitor, Cpd10, to phenocopy genetic ablation of FoxO1. We evaluated the therapeutic impact of genetic ablation or chemical inhibition of FoxO1 on insulin-deficient diabetes in Ins2Akita/+ mice. RESULTS: Pan-intestinal epithelial FoxO1 ablation expanded the EEC pool, induced ß-like cells, and improved glucose tolerance in Ins2Akita/+ mice. This genetic effect was phenocopied by Cpd10. Cpd10 induced ß-like cells that released insulin in response to glucose in gut organoids, and this effect was enhanced by the Notch inhibitor, DBZ. In Ins2Akita/+ mice, a five-day course of either Cpd10 or DBZ induced intestinal insulin-immunoreactive ß-like cells, lowered glycemia, and increased plasma insulin levels without apparent adverse effects. CONCLUSION: These results provide proof of principle of gut cell conversion into ß-like cells by a small molecule FoxO1 inhibitor, paving the way for clinical applications.


Assuntos
Diabetes Mellitus , Células Secretoras de Insulina , Animais , Camundongos , Células Enteroendócrinas , Proteína Forkhead Box O1/genética , Glucose/farmacologia , Insulina/genética , Organoides , Receptores Notch/antagonistas & inibidores
10.
Mol Metab ; 49: 101187, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33577983

RESUMO

OBJECTIVE: Forkhead box protein O1 (FOXO1) plays a key role in regulating hepatic glucose production, but investigations of FOXO1 inhibition as a potential therapeutic approach have been hampered by a lack of selective chemical inhibitors. By profiling structurally diverse FOXO1 inhibitors, the current study validates FOXO1 as a viable target for the treatment of diabetes. METHODS: Using reporter gene assays, hepatocyte gene expression studies, and in vivo studies in mice, we profiled our leading tool compound 10 and a previously characterized FOXO1 inhibitor, AS1842856 (AS). RESULTS: We show that AS has significant FOXO1-independent effects, as demonstrated by testing in FOXO1-deficient cell lines and animals, while compound 10 is highly selective for FOXO1 both in vitro and in vivo and fails to elicit any effect in genetic models of FOXO1 ablation. Chronic administration of compound 10 improved insulin sensitivity and glucose control in db/db mice without causing weight gain. Furthermore, chronic compound 10 treatment combined with FGF21 led to synergistic glucose lowering in lean, streptozotocin-induced diabetic mice. CONCLUSIONS: We show that the widely used AS compound has substantial off-target activities and that compound 10 is a superior tool molecule for the investigation of FOXO1 function. In addition, we provide preclinical evidence that selective FOXO1 inhibition has potential therapeutic benefits for diabetes as a monotherapy or in combination with FGF21.


Assuntos
Glicemia/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Proteína Forkhead Box O1/metabolismo , Animais , Diabetes Mellitus Tipo 2/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Proteína Forkhead Box O1/efeitos dos fármacos , Proteína Forkhead Box O1/genética , Glucose/metabolismo , Hepatócitos/metabolismo , Resistência à Insulina , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Quinolonas/farmacologia
11.
Carcinogenesis ; 31(6): 1092-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20164123

RESUMO

Activation of the mammalian target of rapamycin (mTOR) pathway promotes tumorigenesis, and inhibiting the mammalian target of rapamycin complex 1 (mTORC1) has emerged as an attractive target for suppressing tumor growth. We found that selenium treatment of HT-29 colon cancer cells suppressed mTORC1 through Akt-independent and -dependent pathways. In Akt-independent mTORC1 inhibition in selenium-treated colon cancer cells, adenosine monophosphate-activated protein kinase (AMPK) alpha(1) was crucial for suppression of mTORC1 activity. In contrast, the Akt-dependent mTORC1 inhibition by selenium did not require AMPKalpha(1). The importance of the AMPKalpha(1)-mTORC1 pathway in mediating the antiproliferative action of selenium was examined in xenograft tumors, and the suppression of mTORC1 as well as Akt was concomitant with an increase in AMPKalpha(1) activity. These findings suggest that the antiproliferative effect of selenium is mediated by an Akt-independent AMPKalpha(1)/mTORC1 pathway or by the Akt/tuberous sclerosis complex 2 /mTORC1 pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias do Colo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Selênio/farmacologia , Animais , Western Blotting , Proliferação de Células , Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Ativação Enzimática , Células HT29 , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosforilação , RNA Interferente Pequeno , Serina-Treonina Quinases TOR
12.
Exp Mol Med ; 41(3): 201-7, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-19293639

RESUMO

AMPK (AMP-activated protein kinase) is highly conserved in eukaryotes, where it functions primarily as a sensor of cellular energy status. Recent studies indicate that AMPK activation strongly suppresses cell proliferation in non-malignant cells as well as in tumor cells. In this study, quercetin activated AMPK in MCF breast cancer cell lines and HT-29 colon cancer cells, and this activation of AMPK seemed to be closely related to a decrease in COX-2 expression. The application of a COX-2 inhibitor or cox-2-/- cells supported the idea that AMPK is an upstream signal of COX-2, and is required for the anti-proliferatory and pro-apoptotic effects of quercetin. The suppressive or growth inhibitory effects of quercetin on COX-2 were abolished by treating cancer cells with an AMPK inhibitor Compound C. These results suggest that AMPK is crucial to the anti-cancer effect of quercetin and that the AMPK-COX-2 signaling pathway is important in quercetin-mediated cancer control.


Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Anticarcinógenos/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/fisiologia , Quercetina/farmacologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ativação Enzimática , Humanos , Pirazóis/farmacologia , Pirimidinas/farmacologia
13.
Nat Protoc ; 14(11): 3059-3081, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31586162

RESUMO

The study of cerebral microvessels is becoming increasingly important in a wide variety of conditions, such as stroke, sepsis, traumatic brain injury and neurodegenerative diseases. However, the molecular mechanisms underlying cerebral microvascular dysfunction in these conditions are largely unknown. The molecular characterization of cerebral microvessels in experimental disease models has been hindered by the lack of a standardized method to reproducibly isolate intact cerebral microvessels with consistent cellular compositions and without the use of enzymatic digestion, which causes undesirable molecular and metabolic changes. Herein, we describe an optimized protocol for microvessel isolation from mouse brain cortex that yields microvessel fragments with consistent populations of discrete blood-brain barrier (BBB) components (endothelial cells, pericytes and astrocyte end feet) while retaining high RNA integrity and protein post-translational modifications (e.g., phosphorylation). We demonstrate that this protocol allows the quantification of changes in gene expression in a disease model (stroke) and the activation of signaling pathways in mice subjected to drug administration in vivo. We also describe the isolation of genomic DNA (gDNA) and bisulfite treatment for the assessment of DNA methylation, as well as the optimization of chromatin extraction and shearing from cortical microvessels. This optimized protocol and the described applications should improve the understanding of the molecular mechanisms governing cerebral microvascular dysfunction, which may help in the development of novel therapies for stroke and other neurologic conditions.


Assuntos
Encéfalo/irrigação sanguínea , Microvasos/citologia , Animais , Astrócitos/química , Astrócitos/citologia , Barreira Hematoencefálica/química , Barreira Hematoencefálica/citologia , Química Encefálica , DNA/análise , Células Endoteliais/química , Células Endoteliais/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microvasos/química , Pericitos/química , Pericitos/citologia , RNA/análise
14.
Oncol Rep ; 35(3): 1566-72, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26707164

RESUMO

Selenium has received much attention as an anticancer agent, although the mechanisms of action underlying its pro-apoptotic properties remain unclear. Tumors that respond well to antioxidant treatments, such as hepatocellular carcinoma (HCC), may benefit from treatment with selenium as this compound also has antioxidant properties. Furthermore, a major oncogenic driver in HCC is the nuclear transcription co-activator, ß-catenin. In the present study, we examined the mechanism by which selenium reduces survival of HCC cells, and whether this was associated with modulation of the ß-catenin pathway. Hep3B cell lines and cancer cell xenografted animals were treated with selenium, and apoptotic events or signals such as AMPK, ß-catenin and GSK3ß were determined. Further interactions among ß-catenin, glycogen synthase kinase 3ß (GSK3ß), and AMPK were explored by applying AMPK small interfering RNA (siRNA) or GSK3ß siRNA with western blotting or immunofluorescence microscopic observation. Selenium activated AMPK, which in turn suppressed ß-catenin. Selenium induced the translocation of AMPK into the nucleus and prevented the accumulation of ß-catenin therein. Upon inactivation of AMPK by AMPK siRNA, selenium no longer modulated ß-catenin, implying that AMPK is an upstream signal for ß-catenin. We found that the binding between AMPK and ß-catenin occurs in the cytosolic fraction, and therefore concluded that the cancer cell antiproliferative effects of selenium are mediated by a GSK3ß-independent AMPK/ß-catenin pathway, although AMPK-mediated GSK3ß regulation was also observed. We primarily discovered that AMPK is a crucial regulator initiating selenium-induced inhibition of ß-catenin expression. Taken together, these novel findings help to illuminate the molecular mechanisms underlying the anticancer effect of selenium and highlight the regulation of ß-catenin by selenium.


Assuntos
Proteínas Quinases Ativadas por AMP/biossíntese , Carcinoma Hepatocelular/tratamento farmacológico , Quinase 3 da Glicogênio Sintase/biossíntese , Neoplasias Hepáticas/tratamento farmacológico , Selênio/administração & dosagem , beta Catenina/biossíntese , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citosol , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Ligação Proteica , RNA Interferente Pequeno , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética , beta Catenina/metabolismo
15.
Exp Toxicol Pathol ; 65(1-2): 1-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21724378

RESUMO

Cyclooxygenase-2 (COX-2), the key enzyme of the conversion of arachidonic acid to prostaglandins is an important regulator of inflammation and perhaps apoptosis. Genistein is an active component of legumes and other related food associated with prevention of degenerative diseases possibly through modulating certain signaling pathways. It was investigated whether the induction of apoptosis with genistein was carried out via COX-2 suppression through the regulation of NF-κB. The cox-2 positive and negative cells were used to compare the effect of genistein on the modulation of NF-κB in COX-2 expressed or non-expressed genotypic systems. Suppression of COX-2 as well as decreasing NF-κB DNA binding activity was accompanied with the induction of apoptosis in genistein-treated COX-2 expressed cells. However, in cox-2 negative cells, apoptosis occurred without any involvement of NF-κB with genistein treatement. Genistein induced apoptosis through the generation of reactive oxygen species (ROS) both of cox-2 positive and negative cells. These results suggested that genistein is capable of exihibiting NF-κB-dependent and NF-κB-independent apoptotic control via ROS generation depending on genetic cell types.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Genisteína/farmacologia , Glycine max/química , NF-kappa B/metabolismo , Animais , Western Blotting , Celecoxib , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Dinoprostona/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Ensaio de Imunoadsorção Enzimática , Genisteína/isolamento & purificação , Marcação In Situ das Extremidades Cortadas , Pirazóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sulfonamidas/farmacologia
16.
Oncol Rep ; 24(6): 1493-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21042744

RESUMO

In lieu of elucidating bidirectional connecting mechanism between AMP-activated protein kinase (AMPK) and survival signal Akt we applied MCF-7 breast cancer cells to determine whether AMPK modulation alters Akt signals and vice versa. Suppression of Akt activities with a synthetic Akt inhibitor alleviated AMPK activities suggesting that Akt is capable of inhibiting AMPK. Also the activation of AMPK with quercetin strongly abrogated Akt activities. Treating cancer cells with AMPK siRNA or Compound C resulted in marked increment of Akt dephosphorylation indicating that AMPK has antagonistic activities towards Akt. However, quercetin exerted Akt inhibitory activities in the absence of AMPK activation. Quercetin induced partial co-localization of phospho-Akt and phospho-AMPK in the nucleus even though their interaction seems to be indirect since the immunoprecipitation data indicate there was no direct binding between total Akt and AMPK. These results suggest there is a mutual suppressive interaction between AMPK and Akt. The investigation of mutual suppression between Akt and AMPK by chemo-preventive agents such as quercetin may provide a mechanistic rational for controlling breast tumor cell growth.


Assuntos
Adenilato Quinase/antagonistas & inibidores , Adenilato Quinase/metabolismo , Neoplasias da Mama/patologia , Carcinoma/patologia , Proteína Oncogênica v-akt/antagonistas & inibidores , Proteína Oncogênica v-akt/metabolismo , Quercetina/farmacologia , Adenilato Quinase/fisiologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Modelos Biológicos , Proteína Oncogênica v-akt/fisiologia , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Quercetina/uso terapêutico , RNA Interferente Pequeno/farmacologia
17.
Oncol Rep ; 24(6): 1471-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21042741

RESUMO

AMP-activated protein kinase (AMPK) has emerged as a therapeutic target of cancer. AMPK functions as an upstream regulator of proliferative signals such as mammalian target of rapamycin (mTOR), tuberous sclerosis complex (TSC), p70S6 and elongation factor-2, indicating that AMPK can be applied for the inhibition of cancer cell proliferation via modulating the proliferative signaling network. The Akt/mTOR signaling pathway is activated in colon cancer. The well known mTOR inhibitor rapamycin has a disadvantage of feedback stimulation of Akt. Anthocyanins are naturally-occurring mTOR inhibitor possessing Akt inhibitory activities. We have investigated the mTOR inhibitory effect of anthocyanins through the activation of AMPK. In this study, anthocyanins were applied to colon cancer cells and tumor-bearing xenograft models to investigate their anti-proliferative and pro-apoptotic effects, and elucidate the mechanisms that link AMP-activated protein kinase (AMPK) α1 activation to the survival signal of mTOR. Our results indicated that anthocyanins significantly decreased phospho-mTOR comparable to rapamycin, a synthetic mTOR inhibitor, and this inhibitory effect of anthocyanins on mTOR was completely abrogated by inactivating AMPKα1. Furthermore, suppression of cell growth with anthocyanins was also alleviated in the absence of noticeable AMPKα1 activities. For the first time we have found anthocyanins as novel AMPKα1 activators, and in conditions of AMPKα1 inactivation, anthocyanins lost their ability to inhibit mTOR in HT-29 colon cancer cells. The activation of AMPKα1, and the deactivation of mTOR and Akt were observed in anthocyanins-treated tumor-bearing xenograft models. The results from this study suggest that there is a complex interaction between AMPKα1 and mTOR signaling, and anthocyanins are powerful AMPKα1 activators that inhibit cancer cell growth by inhibiting mTOR phosphorylation.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antocianinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias/patologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Antineoplásicos/farmacologia , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Células HT29 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Cancer Lett ; 292(2): 228-36, 2010 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-20083342

RESUMO

Effective strategies for cancer prevention and treatment can be identified by understanding the mechanism of apoptotic pathways. In this study, we investigated the regulatory mechanism of quercetin-induced apoptosis through apoptosis signal-regulating kinase (ASK)-1 and mitogen-activated protein kinase pathways. Our results showed that quercetin increased apoptotic cell death through reactive oxygen species (ROS) generation and was responsible for ASK1 activation. Increasing ASK1 activity was accompanied by p38 activation. Interestingly, AMP-activated protein kinase (AMPK) seemed to be a critical controller of quercetin-regulated ASK1/p38 activation. Blocking AMPKalpha1 activity using Compound C, a synthetic inhibitor or siRNA showed that quercetin-activated ASK1 could not stimulate p38 activity. Thus, we suggested that quercetin-exerted apoptotic effects involve ROS/AMPKalpha1/ASK1/p38 signaling pathway, and AMPKalpha1 is a necessary element for apoptotic event induced by ASK1.


Assuntos
Adenilato Quinase/metabolismo , Apoptose/efeitos dos fármacos , MAP Quinase Quinase Quinase 5/metabolismo , Quercetina/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Microscopia de Fluorescência , Espécies Reativas de Oxigênio/metabolismo
19.
Immune Netw ; 10(6): 212-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21286382

RESUMO

BACKGROUND: The stem bark of Kalopanax pictus (KP) has been used in traditional medicine to treat rheumatoidal arthritis, neurotic pain and diabetes mellitus in China and Korea. In this study, the mechanism responsible for anti-inflammatory effects of KP was investigated. METHODS: We examined the effects of KP on NO production, nitric oxide synthase (iNOS) and HO-1 expression, NF-κB, Nrf2 and MAPK activation in mouse peritoneal macrophages. RESULTS: The aqueous extract of KP inhibited LPS-induced NO secretion as well as inducible iNOS expression, without affecting cell viability. KP suppressed LPS-induced NF-κB activation, phosphorylation and degradation of IκB-α, phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK). Furthermore, KP induced HO-1 expression and Nrf2 nuclear translocation. CONCLUSION: These results suggest that KP has the inhibitory effects on LPS-induced NO production in macrophages through NF-κB suppression and HO-1 induction.

20.
Food Chem Toxicol ; 48(3): 903-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20060025

RESUMO

We isolated anthocyanins from fruits of Vitis coignetiae Pulliat, characterized the anthocyanin profile, and investigated the anti-invasive effects of the anthocyanins on human colon cancer cells. The anthocyanins inhibited cell invasion in a dose-dependent manner, as measured by Matrigel invasion assays, by suppression of matrix metalloproteinase (MMP)-2 and MMP-9 expression. The anti-invasive activity of the anthocyanins was associated with modulation of constitutive nuclear factor kappaB (NF-kappaB) activation. The activation of NF-kappaB triggered by tumor necrosis factor-alpha was also inhibited by the anthocyanins through suppression IkappaBalpha phosphorylation. AIMs inhibited the expression of NF-kappaB-regulated proteins. In conclusion, this study suggested that the anthocyanins isolated from fruits of V. coignetiae Pulliat should have anti-invasive activities on human colon cancer cells and the activities should be related to the inhibition of NF-kappaB-regulated proteins such as MMP-2 and MMP-9 expression through the inhibition of NF-kappaB activation.


Assuntos
Antocianinas/química , Antocianinas/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Vitis/química , Western Blotting , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Citometria de Fluxo , Células HT29 , Humanos , Quinase I-kappa B/metabolismo , Imuno-Histoquímica , Luciferases/biossíntese , Luciferases/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/biossíntese , NF-kappa B/genética , Invasividade Neoplásica , Espectrometria de Massas por Ionização por Electrospray , Transfecção , Cicatrização/efeitos dos fármacos
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