Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 3 de 3
Filter
Add more filters










Language
Publication year range
1.
São Paulo; s.n; s.n; 2021. 60 p. tab, graf.
Thesis in English | LILACS | ID: biblio-1415547

ABSTRACT

Unprotected chronic exposure to ultraviolet radiation generates many harmful effects to human skin and UV filters are essential to health, however, traditional sunscreens do not provide enough protection against cutaneous oxidative stress, a process amplified by UV radiation. Therefore, is been proposed the development of multifunctional photoprotective formulations, acting in the absorption/reflection of UV radiation and assisting in cutaneous homeostasis. In the present study, ferulic acid is used in conjunction with two sunscreens, bemotrizinol and ethylhexyl triazone, for the determination of biosafety and efficacy methods, using techniques that better elucidate the effects of ferulic acid. Skin permeation assays were performed by applying a formulation containing the three substances in the stratum corneum of volunteers, which were removed by the tape stripping method (ex vivo) with follow quantification by high performance liquid chromatography (HPLC). The test was able to evaluate the penetration depth of the substances, characterizing them. In addition, the simultaneous quantification of the three substances was performed by a single and fast method, facilitating their analysis and improving the technique. Also, TBARS (thiobarbituric acid reactive substances) assays were performed in stratum corneum removed by tape stripping (ex vivo), evaluating the potential of cutaneous lipid peroxidation, with or without ferulic acid. To date, it is the first time that TBARS method is used to characterize the stratum corneum (ex vivo) and quantified by HPLC. The protocol developed may aid in the efficacy of antioxidant agents in studies aimed at elucidating the level of lipid peroxidation caused by drugs and cosmetics, and even in carrying out baseline studies characterizing different ethnicities and genders. As last, an anti-inflammatory in vivo assay with Laser Doppler flowmetry equipment was used to compare the sunscreen formulation with or without ferulic acid. Data indicated that the antioxidant reduced the angular coefficient of the perfusion units, mitigating the inflammatory effects. Furthermore, a significant difference was found between the genders, suggesting a more pronounced inflammatory reaction in women. Ferulic acid proved to be a valuable resource, besides being safe and raise the SPF of sunscreens, it also mitigates the effects of inflammation


A exposição crônica desprotegida à radiação ultravioleta (UV) contribui para o desenvolvimento de câncer de pele e os filtros solares são relevantes para evitar tais efeitos prejudiciais, porém, os protetores solares tradicionais não geram proteção suficiente contra o estresse oxidativo cutâneo. Logo, espera-se o desenvolvimento de formulações fotoprotetoras multifuncionais, atuando não somente na absorção e/ou reflexão da radiação UV, mas, também, auxiliando na homeostase cutânea, com presença de agentes antioxidantes. No presente estudo foi utilizado o ácido ferúlico conjuntamente com dois filtros solares, o bemotrizinol e a triazona de octila, para determinação de métodos de segurança e eficácia, utilizando técnicas que melhor elucidem e comprovem os efeitos do ácido ferúlico. Foram realizados ensaios de permeação cutânea pela aplicação tópica de formulação contendo as três substâncias em voluntários, sendo o estrato córneo retirado pelo método de tape stripping (ex vivo) com subsequente quantificação por cromatografia líquida de alta eficiência (CLAE). O ensaio pôde avaliar a profundidade de penetração das substâncias, caracterizando-as. Ademais, a quantificação simultânea das três substâncias foi efetuada por método único e rápido, facilitando análise com aprimoramento da técnica. Em adição, foi realizado ensaios de TBARS (substâncias reativas ao ácido tiobarbitúrico) em estrato córneo removido por tape stripping (ex vivo), para avaliar o potencial de peroxidação lipídica cutânea, contendo ou não o ácido ferúlico. Até o presente momento, é a primeira vez que o método TBARS é utilizado para caracterização do estrato córneo (ex vivo) e quantificada por CLAE. O protocolo desenvolvido pode auxiliar na eficácia de agentes antioxidantes, em estudos que visam elucidar o nível de peroxidação lipídica causada por medicamentos e cosméticos e, até mesmo, na realização de estudos de base, caracterizando etnias e gêneros. Ademais, um ensaio anti-inflamatório in vivo com equipamento de fluxometria Laser Doppler foi utilizado para comparar a formulação fotoprotetora com ou sem ácido ferúlico. Os dados indicaram que o antioxidante reduziu o coeficiente angular das unidades de perfusão, mitigando os efeitos inflamatórios. Ainda, foi identificada diferença entre os gêneros, sugerindo reação inflamatória mais pronunciada em mulheres. O ácido ferúlico provou ser um recurso valioso, além de ser seguro e elevar o FPS dos fotoprotetores, também atenuando os efeitos da inflamação


Subject(s)
Sunscreening Agents/analysis , Efficacy , Protective Factors , Anti-Inflammatory Agents/analysis , Antioxidants/administration & dosage , Radiation , Skin Neoplasms/classification , Ultraviolet Rays/adverse effects , Pharmaceutical Preparations/analysis , Chromatography, High Pressure Liquid/methods , Thiobarbituric Acid Reactive Substances/pharmacology , Laser-Doppler Flowmetry/methods , Oxidative Stress/drug effects , Cosmetics/classification , Diagnosis
2.
Prostate ; 79(5): 515-535, 2019 04.
Article in English | MEDLINE | ID: mdl-30585351

ABSTRACT

BACKGROUND: Chronic inflammation has been implicated in cancer etiology and angiogenesis is stimulated in this disease. In prostate, the crosstalk between malignant epithelial cells and their microenvironment is an essential step of tumorigenesis during which glandular stroma undergo changes designated as reactive stroma. Thus, the aim herewith was to evaluate the effects of associating anti-inflammatory and antiangiogenic therapies on cancer progression, correlating them with steroid hormone receptor (AR and ERα), reactive stroma (vimentin, αSMA, and TGF-ß), and cell proliferation (PCNA) markers expression in the Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) model. METHODS: TRAMP mice (12-week old) were divided into the groups: Control (TRCON): received the vehicles used for drug dilution; Celecoxib (TRCEL): received oral doses of the anti-inflammatory drug celecoxib (15 mg/kg) twice daily; Nintedanib (TRNTB): received oral doses of the antiangiogenic drug nintedanib (10 mg/kg) daily; Nintedanib+Celecoxib (TRNTCEL): received the combination of drugs. After 6 weeks, mice were euthanized and ventral prostate samples were harvested for morphological, immunohistochemical, and Western blotting analyses. RESULTS: While celecoxib led to fibromuscular hypertrophy attenuation, nintedanib significantly reduced the incidence of well-differentiated adenocarcinoma (WDAC) foci in relation to controls, both when administered per se or in association to celecoxib. Furthermore, drug combination was associated with unique effects, including lower incidence of HGPIN lesions; lower AR stromal distribution; changes in ERα localization from epithelial nuclei to stroma as well as significant decrease of TGF-ß levels and associated angiogenesis. In parallel, all treatments applied resulted in reduced inflammatory marker and vimentin (VIM) expression. CONCLUSIONS: Celecoxib plus nintedanib is an effective antitumor combination against prostate cancer progression in TRAMP mice, showing remarkable efficacy in relation to isolated therapies. Importantly, this efficacy might be due to drug association effect on driving AR and mainly ERα distribution in the prostatic tissue towards benign patterns. In addition, celecoxib and nintedanib impaired the development of a stromal reaction by reducing the recruitment of reactive stroma cells and maintaining a normal smooth muscle cell-rich prostate stroma in TRAMP mice. Collectively, these findings pointed to the beneficial effects of combining anti-inflammatory and antiangiogenic strategies to prevent or delay prostatic tumorigenesis.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Prostate/drug effects , Prostatic Neoplasms/prevention & control , Animals , Celecoxib/pharmacology , Disease Progression , Drug Synergism , Drug Therapy, Combination , Estrogen Receptor alpha/biosynthesis , Indoles/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Precancerous Conditions/drug therapy , Precancerous Conditions/pathology , Prostate/blood supply , Prostate/metabolism , Prostate/pathology , Prostatic Neoplasms/blood supply , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Receptors, Androgen/biosynthesis , Stromal Cells/drug effects , Stromal Cells/metabolism , Stromal Cells/pathology
3.
Cell Biol Int ; 42(8): 1006-1020, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29603508

ABSTRACT

Prostate cancer is the second most diagnosed cancer in the world, and alternative methods to prevent and treat different lesion grades need to be evaluated. The objective was to evaluate the morphological, hormonal, and inflammatory responses in the prostate anterior lobe in transgenic adenocarcinoma of the mouse prostate (TRAMP), following Celecoxib and Goniothalamin (GTN) treatments. All animals were treated for 4 weeks, from 8 weeks of age and euthanized either immediately after treatment (12-week-old mice: immediate response) or later (22-week-old mice: late response). The results showed a significant increase of high-grade prostatic intraepithelial neoplasia (HGPIN) and well-differentiated adenocarcinoma (WDA), according to the age in the control groups. Celecoxib treatment decreased the WDA incidence in the late response group. GTN led to a significant healthy tissue increase, and an LGPIN and HGPIN decrease in the immediate response group. In the late response group, GTN led to healthy area increase and there was no occurrence of WDA. AR and ERα immunoexpressions were reduced by both treatments in the immediate response groups. However, only GTN was able to decrease the ERα level in the late response group. Regarding COX-2 immunoreactivity, both treatments reduced the frequency of this enzyme. We can conclude that the prostate anterior lobe is a good model to study prostate cancer, considering its slow progression. Both treatments led to cancer delay in the prostate anterior lobe. However, GTN pointed towards a better treatment spectrum in the signaling pathways in the prostate microenvironment, particularly in ERα.


Subject(s)
Celecoxib/therapeutic use , Prostatic Neoplasms/drug therapy , Pyrones/therapeutic use , Adenocarcinoma/drug therapy , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Animals , Cyclooxygenase 2/metabolism , Disease Models, Animal , Estrogen Receptor alpha/metabolism , Immunohistochemistry , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neoplasm Grading , Proliferating Cell Nuclear Antigen/metabolism , Prostate/metabolism , Prostate/pathology , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Receptors, Androgen/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...