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1.
São Paulo; s.n; s.n; 2019. 98 p. tab, ilus, graf.
Tesis en Portugués | LILACS | ID: biblio-1024842

RESUMEN

O carcinoma hepatocelular (HCC) é a neoplasia primária mais frequente que acomete o fígado, a quarta principal causa de morte relacionada ao câncer e apresenta mau prognóstico. A fibrose hepática está presente em grande parte dos casos de HCC e é um dos principais fatores de risco para esta afecção. Segundo estudos prévios do grupo, a ß-ionona (BI), presente em uvas e aromatizantes de vinho, apresenta potencial quimiopreventivo na hepatocarcinogênese principalmente por reduzir o número e tamanho de lesão pré neoplásica (LPN) e inibir a proliferação celular. No entanto, até o presente não foram identificados na literatura estudos que investigaram o efeito deste isoprenóide no processo fibrótico e na hepatocarcinogênese a ele associada. Desta forma, este estudo pretendeu investigar o potencial efeito quimiopreventivo da BI na hepatocarcinogênese associada à fibrose hepática. Para tanto, ratos machos Wistar foram tratados com óleo de milho (OM) [0,25 ml / 100 g de peso corporal (p.c.); Grupo de OM] ou BI (16mg / 100g p.c.; Grupo BI) durante 18 semanas. A partir da 2ª semana, todos os animais receberam uma dose intraperitoneal de dietilnitrosamina (DEN - 50 mg / Kg p.c.) uma vez por semana até a 16ª semana. Os animais foram eutanasiados em diferentes períodos do protocolo experimental: na 10a semana (grupos OMP1 e BIP1), na 14a semana (grupos OMP2 e BIP2) e na 18ª semana (grupos OMP3 e BIP3). O isoprenóide demonstrou, de maneira inédita na literatura, inibir o desenvolvimento da fibrose hepática em diferentes estágios da hepatocarcinogênese (pontos 1, 2 e 3) por reduzir (p < 0,05) a porcentagem de área marcada para picrosirius. Além disso, BI reduziu a porcentagem de área positiva para α- SMA (p < 0,05) e as concentrações de hidroxiprolina (p < 0,05) no ponto 2. Foi observada ação quimiopreventiva da BI nas fases iniciais da hepatocarcinogênese (pontos 1 e 2) mesmo em modelo associada a fibrose por reduzir (p < 0,05) o número e porcentagem de área do corte ocupada por LPN GSTP positivas. Este efeito não foi observado em fase mais avançada da hepatocarcinogênese (ponto 3). Corroborando este dado não foram observadas diferenças em relação ao número de tumores (p>=0,05) avaliados por imageamento e por análise histopatológica. No entanto, quando comparados ao seu controle (OMP3), os animais do grupo BIP3 apresentaram menor mortalidade e menor incidência (p < 0,05) de HCC high, considerado um tipo mais agressivo de HCC, sugerindo que este composto possa atuar na agressividade das células tumorais. O grupo BIP2 demonstrou ainda menor proliferação celular (p < 0,05) quando comparado ao grupo OMP2. Assim foram avaliadas as vias de proliferação celular PI3K/AKT e MAPK/ERK, bem como as proteínas p21 e p53, relacionadas a progressão do ciclo celular. Não foram observadas(p≥0,05) alterações nestas vias por parte do isoprenóide. O presente estudo demonstrou ação protetora da BI no desenvolvimento de fibrose, bem como na hepatocarcinogênese a ela associada. Contudo, são necessárias análises complementares para elucidar mecanismos pelos quais a BI atua na carcinigênese hepática associada à fibrose


Hepatocellular carcinoma (HCC) is the primary liver cancer, the fourth leading cause of death related to cancer and presents a poor prognosis. Hepatic fibrosis is present in most cases of HCC and represents one of the main risk factors for this condition. According to previous studies of the group, ß-ionone (BI), present in grapes and wine flavorings, has a potential chemopreventive in hepatocarcinogenesis mainly by reducing the number and size of preneoplastic lesions (LPN) and inhibiting cell proliferation. However, to date, no studies have been identified in the literature that investigated the effect of this isoprenoid on the fibrotic process and in its association with hepatocarcinogenesis. Thus, this study aimed to investigate the potential chemopreventive effect of BI in hepatocarcinogenesis associated with hepatic fibrosis. Male Wistar rats were treated with corn oil (OM) [0.25 ml / 100 g body weight (b.w.); OM] or BI group (16mg / 100g b.w; BI group) for 18 weeks. From week 2, all animals received an intraperitoneal dose of diethylnitrosamine (DEN - 50 mg / kg b.w.) once in a week until week 16. The animals were euthanized at different periods of the experimental protocol: at week 10 (groups OMP1 and BIP1), at week 14 (groups OMP2 and BIP2) and week 18 (groups OMP3 and BIP3). The isoprenoid, for the first time in the literature, shown to inhibit the development of liver fibrosis at different stages of hepatocarcinogenesis (points 1, 2 and 3) by reducing (p <0.05) the percentage of the area labeled for picrosirius. Also, BI reduced the percentage of α-SMA positive area (p <0.05) and hydroxyproline concentrations (p <0.05) at point 2. BI chemopreventive action was observed in the early stages of hepatocarcinogenesis (point 1 and 2) even in a model associated with fibrosis for reducing (p <0.05) the number and percentage of the liver section area occupied by GSTP positive LPN. This effect was not observed at a later stage of hepatocarcinogenesis (point 3). Corroborating this data, no differences were observed regarding the number of tumors (p>=0.05) evaluated by imaging and histopathological analysis. However, when compared to its control (OMP3), animals from the BIP3 group had lower mortality and lower incidence (p<0.05) of HCC high, considered a more aggressive type of HCC, suggesting that this compound may act in aggressiveness of tumor cells. The BIP2 group also showed lower cell proliferation (p <0.05) when compared to the OMP2 group. Thus, PI3K / AKT and MAPK / ERK cell proliferation pathways were evaluated, as well as p21 and p53 proteins, related to cell cycle progression. No changes were observed in these pathways by the isoprenoid (p≥0.05). The present study demonstrated the protective action of BI in the development of fibrosis, as well as its association with hepatocarcinogenesis. However, further analysis is needed to elucidate mechanisms by which BI acts on fibrosis-associated liver carcinogenesis


Asunto(s)
Animales , Masculino , Ratas , Norisoprenoides/efectos adversos , Cirrosis Hepática/complicaciones , Neoplasias/prevención & control , Terpenos/uso terapéutico , Fibrosis/tratamiento farmacológico , Carcinoma Hepatocelular/clasificación , Células Estrelladas Hepáticas , Carcinogénesis/patología
2.
PLoS One ; 9(1): e85110, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24416348

RESUMEN

Olfactory receptors (ORs) are expressed in the olfactory epithelium, where they detect odorants, but also in other tissues with additional functions. Some ORs are even overexpressed in tumor cells. In this study, we identified ORs expressed in enterochromaffin tumor cells by RT-PCR, showing that single cells can co-express several ORs. Some of the receptors identified were already reported in other tumors, but they are orphan (without known ligand), as it is the case for most of the hundreds of human ORs. Thus, genes coding for human ORs with known ligands were transfected into these cells, expressing functional heterologous ORs. The in vitro stimulation of these cells by the corresponding OR odorant agonists promoted cell invasion of collagen gels. Using LNCaP prostate cancer cells, the stimulation of the PSGR (Prostate Specific G protein-coupled Receptor), an endogenously overexpressed OR, by ß-ionone, its odorant agonist, resulted in the same phenotypic change. We also showed the involvement of a PI3 kinase γ dependent signaling pathway in this promotion of tumor cell invasiveness triggered by OR stimulation. Finally, after subcutaneous inoculation of LNCaP cells into NSG immunodeficient mice, the in vivo stimulation of these cells by the PSGR agonist ß-ionone significantly enhanced metastasis emergence and spreading.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Proteínas de Neoplasias/agonistas , Norisoprenoides/efectos adversos , Neoplasias de la Próstata/genética , Receptores Odorantes/agonistas , Animales , Calcio/metabolismo , Línea Celular Tumoral , Colágeno/química , Células Enterocromafines/efectos de los fármacos , Células Enterocromafines/metabolismo , Células Enterocromafines/patología , Geles , Humanos , Masculino , Ratones , Ratones SCID , Invasividad Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Trasplante de Neoplasias , Neuronas Receptoras Olfatorias/efectos de los fármacos , Neuronas Receptoras Olfatorias/metabolismo , Neuronas Receptoras Olfatorias/patología , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Transducción de Señal
3.
Contact Dermatitis ; 53(6): 320-3, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16364118

RESUMEN

The purpose of this study is to determine the frequency of responses to selected fragrances in patients with suspected fragrance allergy and to evaluate the risk factors. 9 dermatology departments of university hospitals have participated in this study for the past 1 year. To determine allergic response to fragrances, 18 additional fragrances in addition to the Korean standard and a commercial fragrance series were patch-tested in patients with suspecting cosmetic contact dermatitis. Over 80% of the patients were women, and the most common site was the face. Cinnamic alcohol and sandalwood oil (Santalum album L.) showed high frequencies of positive responses. Of the specific fragrances, ebanol, alpha-isomethyl-ionone (methyl ionone-gamma) and Lyral (hydroxyisohexyl 3-cyclohexane carboxdaldehyde) showed high positive responses. We compared the results obtained during this study with those of other studies and concluded that including additional fragrance allergens may be useful for the detection of fragrance allergy.


Asunto(s)
Dermatitis Alérgica por Contacto/diagnóstico , Perfumes/efectos adversos , Aldehídos/efectos adversos , Alérgenos , Ciclohexenos , Ciclopentanos/efectos adversos , Dermatitis Alérgica por Contacto/etiología , Femenino , Humanos , Corea (Geográfico) , Masculino , Norisoprenoides/efectos adversos , Pruebas del Parche , Pentanoles/efectos adversos , Aceites de Plantas/efectos adversos , Propanoles/efectos adversos , Sesquiterpenos/efectos adversos
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