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1.
Braz. j. biol ; 83: 1-15, 2023. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468904

RESUMO

Background: The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. Aim: The study examined the expression of Neuroglobin (Ngb) and Hypoxia-inducible factor-1α (Hif-1α) in adult and young yak brain tissues, and provided researchers with meaningful insight into the anatomy, physiology, and biochemistry of this mammal. Method: The study employed immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR), and Western blot (WB) to obtain the results. Results: Ngb and Hif-1α were significantly (P<0.05) expressed in the cerebellar cortex, piriform lobe, medulla, and corpus callosum of the adult yak while in the young yak brain tissues, the protein expressions were significantly found in the white matter of the cerebellum, pineal gland, corpus callosum, and cerebellar cortex. The Ngb and Hif-1α expression showed similarities and differences. This may have resulted from similar animal species, source of nutrition, age factors, brain size, emotional activities, and communication. The findings documented that Ngb and Hif-1α are commonly expressed in various adult and young yak brain tissues. Multiple roles in the brain tissues of the adult and young yaks are involved in the expression and distribution and are proposed to play a significant role in the adaptation of the yak to the high altitude environment. Conclusion: This study provides meaningful data to understand the adaptive mechanism to hypoxia and recommended researchers to expand on the adaptive mechanism and brain tissues that are not recorded.


Contexto: O cérebro é um órgão que funciona como o centro do sistema nervoso em todos os animais vertebrados e na maioria dos invertebrados. Objetivo: O estudo examinou a expressão de neuroglobina (Ngb) e fator-1α indutível por hipóxia (Hif-1α) em tecidos cerebrais de iaques adultos e jovens e forneceu aos pesquisadores uma visão significativa da anatomia, fisiologia e bioquímica desse mamífero. Método: O estudo utilizou imuno-histoquímica (IHC), PCR quantitativo em tempo real (qRT-PCR) e western blot (WB) para a obtenção dos resultados. Resultados: Ngb e Hif-1α foram significativamente (P < 0,05) expressos no córtex cerebelar, lobo piriforme, medula e corpo caloso do iaque adulto, enquanto nos tecidos cerebrais do iaque jovem as expressões proteicas foram encontradas significativamente na substância branca do cerebelo, glândula pineal, corpo caloso e córtex cerebelar. A expressão de Ngb e Hif-1α apresentou semelhanças e diferenças. Isso pode ter resultado de espécies animais semelhantes, fonte de nutrição, fatores de idade, tamanho do cérebro, atividades emocionais e comunicação. Os resultados documentaram que o Ngb e o Hif-1α são comumente expressos em vários tecidos cerebrais de iaques adultos e jovens. Múltiplos papéis nos tecidos cerebrais de iaques adultos e jovens estão envolvidos na expressão e distribuição e são propostos para desempenhar um papel significativo na adaptação do iaque ao ambiente de alta altitude. Conclusão: Este estudo fornece dados significativos para compreender o mecanismo adaptativo à hipóxia e recomendou que os pesquisadores expandissem o mecanismo adaptativo e os tecidos cerebrais que não foram registrados.


Assuntos
Animais , Adulto Jovem , Adulto , Bovinos , Bovinos , Cérebro/anatomia & histologia , Cérebro/fisiologia , Fator 1 Induzível por Hipóxia/análise , Fenômenos Bioquímicos , Neuroglobina/análise
2.
Braz. j. biol ; 83: 1-11, 2023. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468926

RESUMO

The telencephalon refers to the most highly developed and anterior part of the forebrain, consisting mainly of the cerebral hemispheres. The study determined Neuroglobin (Ngb) and Hypoxia-inducible factor (HIF-1α) expression in the telencephalon of yak and cattle, and compare the expression and distribution pattern of Ngb and HIF-1α in the two animals. Immunohistochemistry (IHC), quantitative real-time Polymerase Chain Reaction (qRT-PCR), and Western blot (WB) were employed to investigate Ngb and Hif-1α expression in the telencephalon of yak and cattle. mRNA and protein expressions of Ngb and HIF-1α showed positive in different tissues of the yak and cattle telencephalon. Ngb expression in tissues of the yak recorded higher as compare to cattle while HIF-1α expression was found higher in cattle than yak. The HIF-1α expression in some tissues of yak telencephalon was consistent with the cattle. The results documented that HIF-1α may have a direct or indirect synergistic effect on Ngb expression in the yak telencephalon to improve hypoxia adaptation. It is suggested that yak may need more Ngb expression for adaptation, but the expression of HIF-1α seems to be down-regulated during long-term adaptation, and the specific causes of this phenomenon needs to be further verified.


O telencéfalo refere-se à parte anterior e mais desenvolvida do prosencéfalo, consistindo principalmente dos hemisférios cerebrais. O estudo determinou a expressão de neuroglobina (Ngb) e fator indutível por hipóxia (HIF-1α) no telencéfalo de iaques e bovinos e comparou a expressão e o padrão de distribuição de Ngb e HIF-1α nos dois animais. Imuno-histoquímica (IHC), reação em cadeia da polimerase quantitativa em tempo real (qRT-PCR) e Western blot (WB) foram empregados para investigar a expressão de Ngb e Hif-1α no telencéfalo de iaques e bovinos. As expressões de mRNA e proteínas de Ngb e HIF-1α mostraram-se positivas em diferentes tecidos do telencéfalo de iaque e bovino. A expressão de Ngb nos tecidos do iaque foi registrada mais alta em comparação com o gado, enquanto a expressão do HIF-1α foi encontrada mais alta no gado do que no iaque. A expressão de HIF-1α em alguns tecidos do telencéfalo de iaque foi consistente com o gado. Os resultados documentaram que o HIF-1α pode ter um efeito sinérgico direto ou indireto na expressão de Ngb no telencéfalo de iaque para melhorar a adaptação à hipóxia. É sugerido que o iaque pode precisar de mais expressão de Ngb para adaptação, mas a expressão de HIF-1α parece ser regulada para baixo durante a adaptação de longo prazo, e as causas específicas desse fenômeno precisam ser verificadas.


Assuntos
Animais , Bovinos , Fator 1 Induzível por Hipóxia/análise , Neuroglobina/análise , Telencéfalo , Imuno-Histoquímica , Reação em Cadeia da Polimerase em Tempo Real , Western Blotting
3.
J Biomed Mater Res A ; 109(7): 1051-1064, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32876363

RESUMO

Bioactive glasses (BGs) have shown great potential for tissue regeneration and their composition flexibility allows the incorporation of different ions with physiological activities and therapeutic properties in the glass network. Among the many ions that could be incorporated, cobalt (Co) is a significant one, as it mimics hypoxia, triggering the formation of new blood vessels by the vascular endothelial growth factor A (VEGFA), due to the stabilizing effect on the hypoxia inducible factor 1 subunit alpha (HIF1A), an activator of angiogenesis-related genes, and is therefore of great interest for tissue engineering applications. However, despite its promising properties, the effects of glasses incorporated with Co on angiogenesis, through human umbilical cord vein endothelial cells (HUVECs) studies, need to be further investigated. Therefore, this work aimed to evaluate the biocompatibility and angiogenic potential of a new sol-gel BG, derived from the SiO2 -CaO-P2 O5 -CoO system. The structural evaluation showed the predominance of an amorphous glass structure, and the homogeneous presence of cobalt in the samples was confirmed. in vitro experiments showed that Co-containing glasses did not affect the viability of HUVECs, stimulated the formation of tubes and the gene expression of HIF1A and VEGFA. in vivo experiments showed that Co-containing glasses stimulated VEGFA and HIF1A expression in blood vessels and cell nuclei, respectively, in the deep dermis layer of the dorsal region of rats, featuring considerable local stimulation of the angiogenesis process due to Co-release. Co-containing glasses showed therapeutic effect, and Co incorporation is a promising strategy for obtaining materials with superior angiogenesis properties for tissue engineering applications.


Assuntos
Materiais Biomiméticos/química , Cobalto/química , Vidro/química , Fator 1 Induzível por Hipóxia/análise , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular/análise , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biomiméticos/farmacologia , Cobalto/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Ratos Wistar
4.
BMC Complement Altern Med ; 19(1): 324, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752829

RESUMO

BACKGROUND: The present study was designed to investigate the effects of Berberis vulgaris (BV) juice consumption on plasma levels of insulin-like growth factor (IGF-1), IGF-binding proteins (IGFBPs), and the expression of PPAR-γ, VEGF and HIF in women with benign breast disease. METHODS: This parallel design randomized, double-blind controlled clinical trial was conducted on 85 eligible patients diagnosed with benign breast disease. They were assigned randomly into either BV juice group (n = 44, BV juice: 480 ml/day) or placebo group (n = 41, BV placebo juice: 480 ml/day) for 8 weeks intervention. Participants, caregivers and those who assessed laboratory analyses were blinded to the assignments. Plasma levels of biomarkers were measured at baseline and after 8 weeks by ELISA. Quantitative real-time PCR was used to measure the fold change in the expression of each interested gene. RESULTS: The compliance of participants was 95.2% and 40 available subjects analyzed in each group at last. Relative treatment (RT) effects for BV juice caused 16% fall in IGF-1 concentration and 37% reduction in the ratio of IGF-1/1GFBP1. Absolute treatment effect expressed 111 ng/ml increased mean differences of IGFBP-3 between BV group and placebo. Plasma level of PPAR-γ increased in both groups but it was not significant. Fold changes in the expressions of PPAR-γ, VEGF and HIF showed down-regulation in the intervention group compared to placebos (P < 0.05). CONCLUSIONS: The BV juice intervention over 8 weeks was accompanied by acceptable efficacy and decreased plasma IGF-1, and IGF-1/IGFBP-1 ratio partly could be assigned to enhanced IGFBP-1 level in women with BBD. The intervention caused reductions in the expression levels of PPAR, VEGF, and HIF which are remarkable genomic changes to potentially prevent breast tumorigenesis. TRIAL REGISTRATION: IRCT2012110511335N2. Registered 10 July 2013 (retrospectively registered).


Assuntos
Berberis , Neoplasias da Mama , Sucos de Frutas e Vegetais , Adulto , Mama/química , Mama/patologia , Neoplasias da Mama/química , Neoplasias da Mama/dietoterapia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Fator 1 Induzível por Hipóxia/análise , Fator 1 Induzível por Hipóxia/metabolismo , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like I/metabolismo , Pessoa de Meia-Idade , PPAR gama/análise , PPAR gama/metabolismo , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto Jovem
5.
Pancreas ; 48(10): 1312-1320, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31688595

RESUMO

OBJECTIVES: This study aimed to investigate the utility of fluorodeoxyglucose (FDG) positron emission tomography for solid pseudopapillary neoplasm (SPN) diagnosis. METHODS: The subjects included 53 cases of SPN. We compared the maximal standardized uptake volume (SUVmax) with those of 25 cases of pancreatic duct cancer and 18 cases of pancreatic neuroendocrine neoplasm. In addition, immunopathological testing for SPN with regard to FDG uptake was undertaken. RESULTS: An increase in SUVmax was observed in all tumors with increased tumor diameter. Among tumors of 20 mm or smaller, the SUVmax of SPN was significantly higher than those of pancreatic duct cancer and pancreatic neuroendocrine neoplasm. The results of a pathological study of FDG uptake in SPN revealed increased glucose transporter protein type 1 expression with tumor enlargement. Furthermore, increased hypoxia-inducible factor-1 and vascular endothelial growth factor expression under hypoxic conditions were observed in the areas of necrosis. CONCLUSIONS: In cases in which high FDG uptake is observed in small pancreatic tumors, FDG positron emission tomography is potentially useful for SPN differentiation. The factors involved in FDG uptake in SPN include cell density and glucose transporter protein expression, as well as hypoxia-inducible factor and vascular endothelia growth factor expression in the hypoxic environment of necrotic areas.


Assuntos
Carcinoma Papilar/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias Pancreáticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Adolescente , Adulto , Idoso , Carcinoma Papilar/química , Carcinoma Papilar/patologia , Criança , Feminino , Transportador de Glucose Tipo 1/análise , Humanos , Fator 1 Induzível por Hipóxia/análise , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/patologia , Fator A de Crescimento do Endotélio Vascular/análise , Adulto Jovem , Neoplasias Pancreáticas
6.
Histochem Cell Biol ; 152(5): 355-363, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520138

RESUMO

Tuftelin was originally discovered and mostly studied in the tooth, but later found also in other organs. Despite its wide distribution among tissues, tuftelin's function has so far been specified only in the formation of enamel crystals. Nevertheless, in many cases, tuftelin was suggested to be associated with cellular adaptation to hypoxia and recently even with cell differentiation. Therefore, we aimed to investigate tuftelin expression along with hypoxia-inducible factors (HIFs) during the early development of the mandibular/alveolar (m/a) bone, when osteoblasts started to differentiate in vivo and to compare their expression levels in undifferentiated versus differentiated osteoblastic cells in vitro. Immunohistochemistry demonstrated the presence of tuftelin already in osteoblastic precursors which were also HIF1-positive, but HIF2-negative. Nevertheless, HIF2 protein appeared when osteoblasts differentiated, one day later. This is in agreement with observations made with MC3T3-E1 cells, where there was no significant difference in tuftelin and Hif1 expression in undifferentiated vs. differentiated cells, although Hif2 increased upon differentiation induction. In differentiated osteoblasts of the m/a bone, all three proteins accumulated, first, prenatally, in the cytoplasm and later, particularly at postnatal stages, they displayed also peri/nuclear localization. Such a dynamic time-space pattern of tuftelin expression has recently been reported in neurons, which, as the m/a bone, differentiate under less hypoxic conditions as indicated also by a prevalent cytoplasmic expression of HIF1 in osteoblasts. However, unlike what was shown in cultured neurons, tuftelin does not seem to participate in final osteoblastic differentiation and its functions, thus, appears to be tissue specific.


Assuntos
Proteínas do Esmalte Dentário/análise , Fator 1 Induzível por Hipóxia/análise , Osteogênese/genética , Fatores de Transcrição/análise , Células 3T3 , Animais , Células Cultivadas , Proteínas do Esmalte Dentário/genética , Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Camundongos , Fatores de Transcrição/genética
7.
Med Sci Monit ; 25: 4513-4520, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31206507

RESUMO

BACKGROUND The timing of parturition is an important determinant of labor and delivery care. Early parturition is associated with increased neonatal morbidity and mortality. Most existing studies analyzed a single factor for the initiation of parturition, and the role of multiple factors in initiating parturition has not been comprehensively analyzed. MATERIAL AND METHODS We measured the levels of proinflammatory mediators, hypoxia factor, matrix metalloproteinases, hormones, and oxytocin, as well as fetal umbilical blood flow, before and after labor, and their associations with parturition. We also built a statistical model to predict the timing of parturition based on the measurement data. RESULTS IL-1ß, IL-6, TNF-alpha, MMP-9, and HIF-1alpha concentrations significantly increased from full term to labor. The PRL level significantly decreased from full term to parturition. There was no significant change in MCP-1, E3, and OT concentrations from full term to parturition. IL-1ß, IL-6, TNF-alpha, and MMP-9 concentrations were negatively correlated with the initiation of parturition. There was a small but nonsignificant increase in umbilical venous blood flow before parturition. Multiple factors showed a close correlation with the initiation of parturition, and area under the curve analysis showed that a multiple factor model was superior to single factors in the establishment of a model to predict initiation of parturition; however, these results need further confirmation. CONCLUSIONS Combined proinflammatory biomarkers have better predictive value for term labor than single biomarkers.


Assuntos
Previsões/métodos , Parto/metabolismo , Nascimento a Termo/metabolismo , Biomarcadores/sangue , Parto Obstétrico , Feminino , Sangue Fetal , Idade Gestacional , Hormônios/análise , Hormônios/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/análise , Fator 1 Induzível por Hipóxia/metabolismo , Inflamação/metabolismo , Trabalho de Parto , Metaloproteinases da Matriz/análise , Metaloproteinases da Matriz/metabolismo , Modelos Estatísticos , Ocitocina/análise , Ocitocina/metabolismo , Parto/fisiologia , Gravidez , Nascimento a Termo/fisiologia
8.
Mikrochim Acta ; 185(10): 451, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30209641

RESUMO

The authors describe a significantly improved colorimetric nanoprobe for the determination of transcription factors (TFs). It is making use of click-mediated growth of gold nanoparticles (AuNPs) to amplify the signal-to-noise ratio. Hypoxia-inducible factor-1 (HIF-1) is an important TF that acts as a mediator of cell response to hypoxia. So, the detection of HIF-1 was chosen as the model analyte. Specifically, target HIF-1 is designed to bind to the hypoxia response element within DNA duplex. The click chemistry between the DNA duplex and alkynyl-functionalized AuNPs (AF-AuNPs) is then inhibited because of significant steric hindrance. As a result, the AF-AuNPs grow into larger-sized highly-aggregated irregular nanostructures, which in turn enable colorimetric determination. The ratio of absorbances at 620 and 560 nm increases in the 0.5 to 10 nM HIF-1 concentration range, and the detection limit is 0.27 nM. This is better by a factor of 100 than that of aggregation-based colorimetric assays. The nanoprobe is selective and can be used in complex samples. Conceivably, it may also be extended to the determination of other TFs by simply changing the used DNA duplex. Graphical abstract Schematic of a nanoprobe for detecting hypoxia-inducible factor-1 (HIF-1). Three concepts are involved: the binding of HIF-1 and hypoxia response element, the Cu+-catalyzed click chemistry between P1/P2 duplex and alkynyl-functionalized AuNPs (AF-AuNPs), and the AuNPs growth with hydroxylamine and HAuCl4.


Assuntos
Colorimetria/métodos , Ouro/química , Fator 1 Induzível por Hipóxia/análise , Nanopartículas Metálicas/química , Química Click , Humanos , Limite de Detecção
10.
J Periodontal Res ; 53(3): 478-486, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29446089

RESUMO

OBJECTIVE: Grape seed proanthocyanidine extract (GSPE) is a strong antioxidant derived from the grape seeds (Vitis vinifera, Terral J.F.) and has a polyphenolic structure with a wide range of biological activity. The aim of the present study was to evaluate the effects of GSPE on alveolar bone loss and histopathological changes in rats with diabetes mellitus and ligature-induced periodontitis. MATERIAL AND METHODS: Forty rats were divided into 6 study groups. Control (C, 6 rats) group, periodontitis (P, 6 rats) group, diabetes (D, 6 rats) group, diabetes and periodontitis (D+P, 6 rats) group, diabetes, periodontitis and 100 mg/kg/day GSPE (GSPE-100, 8 rats), and diabetes, periodontitis and 200 mg/kg/day GSPE (GSPE-200, 8 rats) group. Diabetes mellitus was induced by intraperitoneal injection of a single dose of streptozotocin (60 mg/kg). Periodontitis was induced via ligation method. Silk ligatures were placed at the mandibular right first molars. GSPE was administered by oral gavage. After 30 days, all rats were killed. Alveolar bone loss was measured morphometrically via a stereomicroscope. For histopathological analyses, Alizarin red staining, and matrix metalloproteinase (MMP)-8, vascular endothelial growth factor and hypoxia inducible factor (HIF)-1α immunohistochemistry were performed. Tartrate-resistant acid phosphatase-positive osteoclast cells and relative total inflammatory cells were also determined. RESULTS: The highest alveolar bone loss was observed in the D+P group (P < .05). GSP-200 group decreased alveolar bone loss (P < .05). The D+P group had the highest osteoclast counts, but the difference was not significant compared to the P, GSPE-100 and GSPE-200 groups (P > .05). The inflammation in the D+P group was also higher than the other groups (P < .05). The osteoblast numbers increased in the GSPE-100 and GSPE-200 groups compared to the P and D+P groups (P < .05). MMP-8 and HIF-1α levels were highest in the D+P group and GSPE significantly decreased these levels (P < .05). CONCLUSION: Within the limits of this animal study, it can be suggested that GSPE administration may decrease periodontal inflammation and alveolar bone loss via decreasing MMP-8 and HIF-1α levels and increase osteoblastic activity in diabetic rats with experimental periodontitis.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/patologia , Diabetes Mellitus Experimental/complicações , Extrato de Sementes de Uva/farmacologia , Extrato de Sementes de Uva/uso terapêutico , Periodontite/tratamento farmacológico , Periodontite/patologia , Proantocianidinas/farmacologia , Proantocianidinas/uso terapêutico , Perda do Osso Alveolar/classificação , Processo Alveolar/patologia , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Glicemia/análise , Peso Corporal , Modelos Animais de Doenças , Extrato de Sementes de Uva/administração & dosagem , Fator 1 Induzível por Hipóxia/análise , Imuno-Histoquímica , Inflamação/tratamento farmacológico , Inflamação/patologia , Injeções Intraperitoneais , Ligadura/efeitos adversos , Masculino , Metaloproteinase 8 da Matriz/análise , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Proantocianidinas/administração & dosagem , Ratos , Ratos Wistar , Estreptozocina/administração & dosagem , Estreptozocina/farmacologia , Fosfatase Ácida Resistente a Tartarato/análise , Fator A de Crescimento do Endotélio Vascular/análise
11.
Int J Cancer ; 138(5): 1058-66, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25784597

RESUMO

The complex cross-talk of intricate intercellular signaling networks between the tumor and stromal cells promotes cancer progression. Hypoxia is one of the most common conditions encountered within the tumor microenvironment that drives tumorigenesis. Most responses to hypoxia are elicited by a family of transcription factors called hypoxia-inducible factors (HIFs), which induce expression of a diverse set of genes that assist cells to adapt to hypoxic environments. Among the three HIF protein family members, the role of HIF-1 is well established in cancer progression. HIF-1 functions as a signaling hub to coordinate the activities of many transcription factors and signaling molecules that impact tumorigenesis. This mini review discusses the complex role of HIF-1 and its context-dependent partners under various cancer-promoting events including inflammation and generation of cancer stem cells, which are implicated in tumor metastasis and relapse. In addition, the review highlights the importance of therapeutic targeting of HIF-1 for cancer prevention.


Assuntos
Hipóxia Celular , Fator 1 Induzível por Hipóxia/fisiologia , Inflamação/etiologia , Neoplasias/etiologia , Animais , Transição Epitelial-Mesenquimal , Humanos , Fator 1 Induzível por Hipóxia/análise , Células-Tronco Neoplásicas/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral
12.
Int J Clin Oncol ; 20(6): 1233-43, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26077139

RESUMO

BACKGROUND: Although the function of hypoxia-inducible factor 1 (HIF1) in many kinds of solid tumor has been revealed, the significance of HIF1 in osteosarcoma is still controversial and not well understood. METHODS: Immunohistochemistry was used to detect HIF1 expression. The correlation between HIF1 and clinicopathology factors was analyzed by use of chi-squared tests. The prognostic value of HIF1 was evaluated by univariate and multivariate analysis. Moreover, the function of HIF1 in osteosarcoma cells was further investigated in in-vitro experiments by regulating HIF1 and vascular endothelial growth factor-A (VEGF-A) expression. RESULTS: Expression of HIF1 was high for 56.82 % of the samples in our investigation. HIF1 expression was significantly associated with positive metastasis (P = 0.037). By use of the Kaplan-Meier method, high expression of HIF1 was proved to be related to poorer overall survival (P = 0.007). By use of a Cox-regression model, HIF1 was identified as an independent prognostic biomarker (P = 0.019). We also proved that HIF1 can promote osteosarcoma invasion in hypoxia by inducing VEGF-A expression. CONCLUSIONS: HIF1 was identified as an independent prognostic biomarker in osteosarcoma. It can promote osteosarcoma cell invasion by inducing VEGF-A expression, indicating that HIF1 is a potential drug target in osteosarcoma.


Assuntos
Neoplasias Ósseas/química , Fator 1 Induzível por Hipóxia/análise , Osteossarcoma/química , Osteossarcoma/secundário , Fator A de Crescimento do Endotélio Vascular/análise , Biomarcadores Tumorais/análise , Neoplasias Ósseas/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Feminino , Técnicas de Silenciamento de Genes , Humanos , Fator 1 Induzível por Hipóxia/genética , Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Invasividade Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto Jovem
13.
BMC Complement Altern Med ; 14: 353, 2014 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-25249371

RESUMO

BACKGROUND: Angiogenesis, which is initiated by certain tumor micro-environmental conditions and diverse protein factors, plays a pivotal role during tumor development and metastasis. Therefore, many efforts have been made to develop effective anti-angiogenic agents as anticancer therapeutics. In the current study, we investigated the anti-angiogenic potential of an ethanol extract of Annona atemoya seeds (EEAA) in vitro and in vivo. METHODS: The anti-angiogenic potential of EEAA was evaluated using various in vitro/in vivo models, including cell proliferation, migration, and tube formation by human umbilical vascular endothelial cells (HUVECs); a Matrigel plug assay; and tumor-induced angiogenesis. The expression of hypoxia-inducible factors (HIFs) and vascular endothelial growth factor (VEGF) was investigated using reverse transcription-polymerase chain reaction, immunoassays, and western blotting. RESULTS: EEAA was able to significantly inhibit the angiogenic properties of HUVECs in vitro as well as angiogenic factor-induced blood vessel formation in vivo. EEAA down-regulated the expression of VEGF and HIF-1alpha/2alpha at the mRNA and protein levels, respectively, in cancer cells under hypoxic conditions. CONCLUSIONS: EEAA shows a strong anti-angiogenic potential in both in vitro and in vivo systems, and we suggest that EEAA may be a valuable herbal source for anticancer drug development.


Assuntos
Inibidores da Angiogênese/farmacologia , Annona/química , Extratos Vegetais/farmacologia , Sementes/química , Análise de Variância , Inibidores da Angiogênese/química , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Etanol , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Fator 1 Induzível por Hipóxia/análise , Fator 1 Induzível por Hipóxia/genética , Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Nus , Extratos Vegetais/química , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Med. clín (Ed. impr.) ; 142(10): 432-437, mayo 2014.
Artigo em Espanhol | IBECS | ID: ibc-120517

RESUMO

Fundamento y objetivo: Estudios recientes evidencian que la expresión del hypoxia-inducible factor 1α (HIF-1α, «factor inducible por la hipoxia 1α») favorece la expresión del vascular endothelial growth factor A (VEGF-A, «factor de crecimiento endotelial vascular A»), así como la proliferación celular, angiogénesis y metástasis en diferentes cánceres, incluido el cáncer de pulmón. El objetivo de este estudio fue investigar la correlación de la expresión del VEGF-A y del HIF-1α con las características clinicopatológicas y el pronóstico de pacientes operados por cáncer de pulmón no microcítico. Pacientes y método: Estudio prospectivo para analizar la expresión de VEGF-A y HIF-1α mediante reacción en cadena de la polimerasa en tiempo real en 66 pacientes operados de cáncer de pulmón no microcítico. Resultados: La edad media (DE) fue de 62,7 (9,8) años y la relación varón:mujer de 7,3:1. Según la nueva clasificación TNM de 2009, los estadios i , ii y iii incluyeron a 27 (40,9%), 21 (31,8%) y 18 (27,3%) pacientes, respectivamente. La histología fue: 47% carcinomas escamosos, 33,3% adenocarcinomas y 19,7% otros. El seguimiento medio fue de 42,3 meses, la mediana de supervivencia de 43,2 meses y la supervivencia estimada a los 5 años del 42,4%. No hubo correlación entre VEGF-A y HIF-1α (p = 0,306). La sobreexpresión de VEGF-A fue más frecuente en el estadio avanzado y cuando hubo metástasis ganglionares (p = 0,034 y p = 0,059, respectivamente). En el análisis multivariante, el descriptor T y el VEGF-A fueron factores pronóstico independientes (odds ratio [OR] 2,37, p = 0,016, y OR 2,51, p = 0,008, respectivamente), mientras que HIF-1α no mostró significación estadística (p = 0,172), con una OR 0,540. Conclusiones: La sobreexpresión de VEGF-A resultó ser un factor pronóstico independiente adverso en pacientes intervenidos de cáncer de pulmón no microcítico. Por el contrario, la sobreexpresión del HIF-1α mostró una tendencia hacia un efecto protector sobre la supervivencia, pero sin significación estadística (AU)


Background and objective Studies suggest that hypoxia-inducible factor 1α (HIF-1α) expression favours expression of vascular endothelial growth factor A (VEGF-A) involving cellular proliferation, angiogenesis, and metastasis in different cancers including lung cancer. We investigated the correlation of HIF-1α and VEGF-A with clinicopathologic parameters and clinical outcomes in surgically resected non-small cell lung cancer patients. Patients and method Prospective study to analyze the expression of VEGF-A and HIF-1α with real time-polymerase chain reaction in 66 patients operated on non-small cell lung cancer. Results Mean age was 62.7 ± 9.8 and male:female ratio was 7.3:1. According to the new 2009 TNM classification, stage i , ii , and iii included 27 (40.9%), 21 (31.8%) and 18 (27.3%) patients, respectively. Histological subtypes were: 47% squamous cell carcinoma, 33.3% adenocarcinoma, and 19.7% others. Mean follow-up time was 42.3 months. Median survival was 43.2 months and 5-year overall survival was 42.4%. There was no correlation between HIF-1α and VEGF-A (P = .306). The overexpression of VEGF-A was found more frequent in advanced stage and in lymph nodes metastasis (P = .034 and P = .059, respectively). In multivariate analysis, T descriptor and VEGF-A overexpression were independent prognostic factors (odds ratio [OR] = 2.37, P = .016, and OR = 2.51, P = .008, respectively). HIF-1α overexpression showed an OR = 0.540, but without statistical significance (P = .172). Conclusions The present study revealed that VEGF-A overexpression was an adverse independent prognostic factor. On the contrary, HIF-1α overexpression showed a tendency to a protective effect on survival of surgically treated non-small cell lung cancer patients, although without statistical significance (AU)


Assuntos
Humanos , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Fator A de Crescimento do Endotélio Vascular/análise , Fator 1 Induzível por Hipóxia/análise , Estudos Prospectivos , Análise de Sobrevida , Neovascularização Patológica/diagnóstico , Metástase Neoplásica/diagnóstico
15.
Dermatol Surg ; 40(5): 511-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24684437

RESUMO

BACKGROUND: The skin color of human hypertrophic scar changes dynamically during scar progression. OBJECTIVE: To investigate whether hypoxia is dynamic during scar progression. METHODS: Thirty-five patients with early, proliferative, regressive, and mature scars were involved in this study. Tissue oxygen tension was measured before scar surgery. After surgery, the scar stage was further defined using hematoxylin and eosin staining, and microvessel density and hypoxia inducible factor-1 (HIF-1) expression were detected using immunohistochemistry to determine a correlation with oxygen level. RESULTS: Mild hypoxia is present in early scars, moderate hypoxia in proliferative scars, and severe hypoxia in regressive scars. Oxygen levels then return to normal in mature scars, which was consistent with the dynamic change in microvessel density. Meanwhile, HIF-1 expression also changed dynamically along with alteration in oxygen levels. CONCLUSION: Hypoxia is dynamic in scar tissue and is possibly correlated with scar formation and regression.


Assuntos
Cicatriz Hipertrófica/sangue , Cicatriz Hipertrófica/patologia , Progressão da Doença , Oxigênio/metabolismo , Adolescente , Adulto , Antígenos CD34/análise , Monitorização Transcutânea dos Gases Sanguíneos , Hipóxia Celular , Corantes , Amarelo de Eosina-(YS) , Feminino , Hematoxilina , Humanos , Fator 1 Induzível por Hipóxia/análise , Masculino , Microvasos , Pessoa de Meia-Idade , Coloração e Rotulagem , Adulto Jovem
16.
Mol Imaging Biol ; 15(6): 713-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23689986

RESUMO

PURPOSE: We aimed to develop a radiolabeled peptide probe for the imaging of hypoxia-inducible factor-1 (HIF-1)-active tumors. PROCEDURES: We synthesized the peptide probes that contain or lack an essential sequence of the oxygen-dependent degradation of HIF-1α in proteasomes ((123/125)I-DKOP30 or (125)I-mDKOP, respectively). The degradation of probes was evaluated in vitro using cell lysates containing proteasomes. In vivo biodistribution study, planar imaging, autoradiography, and comparison between probe accumulation and HIF-1 transcriptional activity were also performed. RESULTS: The (125)I-DKOP30 underwent degradation in a proteasome-dependent manner, while (125)I-mDKOP was not degraded. Biodistribution analysis showed (125)I-DKOP30 accumulation in tumors. The tumors were clearly visualized by in vivo imaging, and intratumoral distribution of (125)I-DKOP30 coincided with the HIF-1α-positive hypoxic regions. Tumoral accumulation of (125)I-DKOP30 was significantly correlated with HIF-1-dependent luciferase bioluminescence, while that of (125)I-mDKOP was not. CONCLUSION: (123)I-DKOP30 is a useful peptide probe for the imaging of HIF-1-active tumors.


Assuntos
Fator 1 Induzível por Hipóxia/análise , Fator 1 Induzível por Hipóxia/metabolismo , Técnicas de Sonda Molecular , Sondas Moleculares/farmacocinética , Peptídeos/química , Sequência de Aminoácidos , Animais , Autorradiografia , Hipóxia Celular , Linhagem Celular Tumoral , Feminino , Células HeLa , Humanos , Fator 1 Induzível por Hipóxia/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Nus , Sondas Moleculares/química , Dados de Sequência Molecular , Peptídeos/farmacocinética , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único
17.
J Endod ; 39(6): 768-73, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23683277

RESUMO

INTRODUCTION: Human dental pulp cells (HDPCs) are recalcitrant to hypoxic stress. We investigated whether hypoxia-induced autophagy of HDPCs offered these cells a survival advantage and the underlying mechanism of this resistance. METHODS: The viability and apoptosis of HDPCs were examined after exposure to hypoxia by Vi-CELL cell viability analyzer and flow cytometry. Autophagy was assessed by using immunofluorescence, acridine orange staining, real-time polymerase chain reaction, and Western blotting. Either 3-methyladenine or expression vectors encoding dominant negative ATG5 were used to inhibit autophagy. Rapamycin was used as an autophagic inducer. To explore the mechanisms of autophagy, adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway and hypoxia-inducible transcription factor-1 were suppressed by chemical inhibitors Compound C and YC-1, respectively. RESULTS: The exposure of HDPCs to hypoxia had no effect on viability and resulted in increasing acidic vesicular organelle-positive cells, autophagosome formation, and up-regulation of autophagy genes. Inhibition of autophagy with 3- methyladenine or expression vectors encoding dominant negative ATG5 abrogated the protective effects of HDPCs. The phosphorylation of AMPK was up-regulated, whereas the phosphorylation of mTOR was down-regulated in hypoxia-treated HDPCs, which were both attenuated by Compound C. Furthermore, treatment with Compound C rather than YC-1 reduced the autophagy. CONCLUSIONS: Our results suggested that autophagy of HDPCs might be cytoprotective against hypoxic stress via the AMPK/mTOR signaling pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Autofagia/fisiologia , Hipóxia Celular/fisiologia , Polpa Dentária/enzimologia , Serina-Treonina Quinases TOR/fisiologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Adenina/análogos & derivados , Adenina/farmacologia , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/análise , Autofagia/efeitos dos fármacos , Proteína 12 Relacionada à Autofagia , Proteína 5 Relacionada à Autofagia , Proteína Beclina-1 , Técnicas de Cultura de Células , Sobrevivência Celular/fisiologia , Células Cultivadas , Polpa Dentária/citologia , Vetores Genéticos/genética , Guanilato Ciclase/farmacologia , Humanos , Fator 1 Induzível por Hipóxia/análise , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Indazóis/farmacologia , Proteínas de Membrana/análise , Proteínas Associadas aos Microtúbulos/análise , Plasmídeos/genética , Proteínas Proto-Oncogênicas/análise , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/análise , Serina-Treonina Quinases TOR/antagonistas & inibidores , Proteínas Supressoras de Tumor/análise
18.
J Oral Maxillofac Surg ; 71(8): 1376-81, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23623199

RESUMO

PURPOSE: Oral pregnancy tumors (OPTs) arise on the inflamed gingiva of women after the first trimester of pregnancy. The expression of angiogenic markers and female hormone receptors was assessed. MATERIALS AND METHODS: Immunohistochemistry was used to analyze the expression of estrogen and progesterone receptors and the expression of angiogenic factors, such as vascular endothelial growth factor (VEGF) and its receptor, fibroblast growth factor (FGF), and hypoxia inducible factors 1α and 3α (HIF1α and HIF3α). Experimental groups included 9 OPTs, 10 oral pyogenic granulomas from nonpregnant women of the same age, and 9 oral pyogenic granulomas from postmenopausal women. RESULTS: VEGF expression in stromal histiocytes and endothelial cells of small vessels was positively correlated in the OPT group (P < .05 by χ(2) test). VEGF receptor also was overexpressed in stromal histiocytes and endothelial cells of OPTs compared with oral pyogenic granulomas from nonpregnant and postmenopausal women (P < .005 by χ(2) test). No correlation was detected among estrogen and progesterone receptors, FGF and HIF1α and HIF3α (ER and PgR respectively) in the 3 experimental groups. CONCLUSIONS: VEGF-associated angiogenesis is most likely involved in the pathogenesis of the lesion. These results imply that local inhibition of VEGF activity could be an adjuvant therapeutic approach for OPTs to control hemorrhage, which can be massive at the surgical excision of such lesions during pregnancy.


Assuntos
Indutores da Angiogênese/análise , Neoplasias Gengivais/metabolismo , Fator 1 Induzível por Hipóxia/análise , Neovascularização Patológica/metabolismo , Complicações Neoplásicas na Gravidez/metabolismo , Receptores de Progesterona/biossíntese , Receptores de Fatores de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese , Adulto , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Fatores de Crescimento de Fibroblastos/análise , Neoplasias Gengivais/complicações , Granuloma Piogênico/metabolismo , Humanos , Pessoa de Meia-Idade , Neovascularização Patológica/complicações , Pós-Menopausa , Gravidez , Receptores de Estrogênio/biossíntese , Adulto Jovem
19.
ChemMedChem ; 8(2): 265-71, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23281069

RESUMO

Diaromatic-substituted ortho- and meta-carboranes were synthesized as mimics of manassantin A. Among the carboranes synthesized, compounds 1 and 2 showed significant inhibition of hypoxia-induced HIF-1 transcriptional activity, with IC(50) values of 3.2 and 2.2 µM, respectively. Compounds 1 and 2 similarly suppressed hypoxia-induced HIF-1α accumulation in a concentration-dependent manner without affecting the expression level of HIF-1α mRNA. The hypoxia-induced accumulation and translocation of HIF-1α into nuclei were not observed in HeLa cells treated with compounds 1 and 2 by immunofluorescence analysis, revealing that the inhibition of hypoxia-induced HIF-1 transcriptional activity is induced by compounds 1 and 2 through a degradation pathway of the HIF-1α protein under hypoxic conditions.


Assuntos
Compostos de Boro/química , Compostos de Boro/farmacologia , Fator 1 Induzível por Hipóxia/genética , Lignanas/química , Lignanas/farmacologia , Ativação Transcricional/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células HeLa , Humanos , Fator 1 Induzível por Hipóxia/análise , Fator 1 Induzível por Hipóxia/metabolismo , RNA Mensageiro/genética , Transdução de Sinais/efeitos dos fármacos
20.
Reprod Biol Endocrinol ; 10: 104, 2012 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-23216940

RESUMO

BACKGROUND: Spermatic cord torsion can lead to testis ischemia (I) and subsequent ischemia-reperfusion (I/R) causing germ cell-specific apoptosis. Previously, we demonstrated that the hypoxia-inducible factor-1 (HIF-1) transcription factor, a key regulator of physiological responses to hypoxia, is abundant in Leydig cells in normoxic and ischemic testes. We hypothesize that testicular HIF-1 activates the expression of antiapoptotic target genes to protect Leydig cells from apoptosis. In silico analysis of testis genes containing a consensus hypoxia response element (HRE, 5'-RCGTG-3') identified myeloid cell leukemia-1 (Mcl-1) as a potential HIF-1 target gene. The purpose of this study was to determine whether HIF-1 shows DNA-binding activity in normoxic and ischemic testes and whether Mcl-1 is a target gene of testicular HIF-1. METHODS: The testicular HIF-1 DNA-binding capacity was analyzed in vitro using a quantitative enzyme-linked immunosorbent assay (ELISA) and electrophoretic mobility shift assays (EMSA). MCL-1 protein expression was evaluated by immunoblot analysis and immunohistochemistry. The binding of testicular HIF-1 to the Mcl-1 gene was examined via chromatin immunoprecipitation (ChIP) analysis. RESULTS: The ELISA and EMSA assays demonstrated that testicular HIF-1 from normoxic and ischemic testes binds DNA equally strongly, suggesting physiological roles for HIF-1 in the normoxic testis, unlike most tissues in which HIF-1 is degraded under normoxic conditions and is only activated by hypoxia. MCL-1 protein was determined to be abundant in both normoxic and ischemic testes and expressed in Leydig cells. In a pattern identical to that of HIF-1 expression, the steady-state levels of MCL-1 were not significantly affected by I or I/R and MCL-1 co-localized with HIF-1α in Leydig cells. Chromatin immunoprecipitation (ChIP) analysis using a HIF-1 antibody revealed sequences enriched for the Mcl-1 promoter. CONCLUSIONS: The results demonstrated that, unlike what is observed in most tissues, HIF-1 displays DNA-binding activity in both normoxic and ischemic testes, and Mcl-1 may be a key target gene of testicular HIF-1 with potential roles in the antiapoptotic protection of Leydig cells.


Assuntos
Fator 1 Induzível por Hipóxia/análise , Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Testículo/química , Animais , Apoptose , Hipóxia Celular , Imunoprecipitação da Cromatina , DNA/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Immunoblotting , Imuno-Histoquímica , Isquemia/metabolismo , Células Intersticiais do Testículo/química , Masculino , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas Proto-Oncogênicas c-bcl-2/análise , Ratos , Ratos Sprague-Dawley , Testículo/irrigação sanguínea
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