Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work had as main objective the development of nanostructured formulations containing rutin, using nanoparticles prepared with alternative vegetables oils. In the first chapter it was demonstrated the feasibility of preparing nanocapsules and nanoemulsions using grape seed or almond kernel oil. Nanocapsule suspensions and nanoemulsions were prepared by the interfacial deposition of preformed polymer and spontaneous emulsification, respectively. All formulations presented nanometric mean size, polydispersity index below 0.30, negative zeta potential, pH values between 6.5 and 7.5 remaining stable after 6 storage months. These formulations promoted the protection of the active against UV degradation, regardless of the type of the oily phase or vesicle. In the second chapter, formulations prepared with grape seed oil were selected for the development of rutin-loaded nanoparticles, as well as to evaluate its in vitro antioxidant activity and photostability. All formulations presented nanometric size, low polydispersity index, acid pH values, negative zeta potential and encapsulation efficiency close to 100 %. Nanoparticles were able to protect rutin against UV photodegradation, if compared to rutin ethanolic solution. In the study of the in vitro antioxidant activity, rutin-loaded nanocapsules and nanoemulsions showed a lower rutin decay rate compared to the rutin ethanolic solution when exposed to UV radiation in the presence of OH radical. However, its presence in nanocapsules led to a prolonged in vitro antioxidant activity compared to the rutin-loaded nanoemulsions. Finally, in the third chapter we studied the development of hydrogels containing rutin (free or associated to polymeric nanocapsules). Their activity on the cutaneous wound healing in rats was evaluated. The developed formulations showed adequate properties regarding their cutaneous administration. In vivo response concerning the healing effect of hydrogels was evaluated by the regression of skin lesions after six days of treatment. Markers of oxidative stress in the lesions of rats were also evaluated, as levels of lipid peroxidation analyzed by the method of thiobarbituric acid reactive substances (TBARS), determination of protein carbonyls levels, total proteins levels, glutathione (GSH) levels, vitamin C and evaluation of the antioxidant enzyme catalase (CAT). This last chapter showed for the first time the feasibility of the dermatological use of such formulations containing rutin to promote the in vivo wound healing. / Este trabalho teve como principal objetivo o desenvolvimento de formulações nanoestruturadas contendo rutina, a partir de nanopartículas contendo óleos vegetais até então não estudados no preparo destas formulações. No primeiro capítulo foi demonstrada a viabilidade de preparar nanocápsulas e nanoemulsões contendo o óleo de semente de uva e de amêndoas doce como fase oleosa. As suspensões de nanocápsulas e nanoemulsões foram preparadas pelo método da deposição interfacial do polímero pré-formado e emulsificação espontânea, respectivamente. Todas as formulações apresentaram tamanho médio nanométrico, índice de polidispersão inferior a 0,30, potencial zeta negativo e valores de pH entre 6,5 e 7,5, permanecendo estáveis após 6 meses de armazenamento. As formulações promoveram a fotoproteção do ativo frente à degradação UV, independente do tipo de fase oleosa e do tipo de vesícula. No segundo capítulo, as formulações contendo o óleo de semente de uva foram selecionadas para o estudo do desenvolvimento de nanopartículas contendo rutina, bem como avaliação de sua atividade antioxidante in vitro e fotoestabilidade. Após o preparo, todas as formulações apresentaram tamanho nanométrico de partículas, baixo índice de polidispersão, valores de pH ácido, potencial zeta negativo e eficiência de encapsulação próxima à 100%. As nanopartículas protegeram a rutina frente à fotodegradação UV, quando comparadas à solução etanólica. No estudo da atividade antioxidante in vitro, as nanocápsulas e nanoemulsões apresentaram uma menor taxa de decaimento da rutina comparada com a solução etanólica, quando expostas à radiação UV em presença do radical ·OH. No entanto, a presença das nanocápsulas levou a uma atividade antioxidante in vitro mais prolongada comparada com as nanoemulsões contendo rutina. Finalmente, no terceiro capítulo estudamos o desenvolvimento de hidrogéis contendo rutina livre ou associada a nanocápsulas poliméricas, avaliando a sua atividade sobre a cicatrização de lesões cutâneas em ratos. As formulações desenvolvidas apresentaram propriedades adequadas para aplicação tópica. A resposta in vivo do efeito cicatrizante foi avaliada através da regressão de lesões na pele após 6 dias de tratamento. Marcadores do estresse oxidativo nas lesões dos ratos foram também avaliados, como os níveis da peroxidação lipídica através do método de TBARS, níveis de proteína carbonilada, níveis de proteínas totais, níveis de glutationa (GSH), vitamina C e avaliação da enzima antioxidante catalase (CAT). Este terceiro capítulo demonstrou pela primeira vez a potencialidade do emprego dermatológico de hidrogéis contendo rutina para a promoção de cicatrização de feridas in vivo.

Le but de notre étude visait à déterminer si les matrices ECM (extracellular matrix) préparés à partir d'un modèle vertébré (Axolotl) capables de régénérer ses tissus suite à une blessure sont plus efficaces pour stimuler les réponses régénératives chez les animaux non régénérant (par exemple les mammifères). Nous avons testé la capacité de matrice ECM axolotl à améliorer la guérison des plaies cutanées dans des souris et nous les avons comparés à une matrice disponible commercialement (échafaudage Symbios PerioDerm) pour leur efficacité à favoriser la guérison des plaies. Des lésions d'excision ont été créées sur le dos de souris et les animaux ont été regroupés dans différents groupes; a-) ECM de peau axolotl décellularisée (groupe Axolotl), b-) matrice de derme acellulaire Symbios Perioderm (groupe PerioDerm), c-) grillage en titane (groupe témoin); respectivement. Les tissus des plaies ont été récoltés à des moments précis : 7 jours et 30 jours après la blessure pour évaluer la guérison des plaies. La guérison des blessures ayant reçu les différentes matrices a été comparées entre elles en utilisant le test de transillumination et des analyses histologiques. Les résultats indiquent que la ECM de peau d’axolotl décellularisée est bien tolérée par les souris, car aucun rejet n'a été observé. Le groupe qui a reçu l'ECM de la peau axolotl décellularisé a démontré une réépithélialisation, une densité cellulaire, une teneur en collagène (avec une organisation similaire à un tissu intact) et une vascularisation (angiogenèse) élevées par rapport aux groupes PerioDerm et témoins. La présence de follicules pileux était également observé dans le groupe axolotl (qui n'est pas présent dans PerioDerm et groupes de contrôle). Sur la base de nos résultats, l'hypothèse de base semble être correcte en ce qu'une matrice ECM provenant d'un régénérateur puissant semble favoriser la guérison plus efficacement chez les animaux normalement non régénérants. Cependant, des recherches supplémentaires devront être menées pour confirmer ces résultats. / The aim of our study sought to determine whether ECM scaffolds prepared from a vertebrate model (Axolotl) capable of regenerating tissues following injury are more effective at stimulating regenerative responses in non-regenerating animals (e.g., mammals). We tested the ability of axolotl decellularized ECM scaffolds to improve skin wound healing in mammalian models and compare the axolotl skin ECM scaffold to a commercially available one (Symbios PerioDerm scaffold) for efficiency in promoting wound healing. Excisional lesions were created on the back of mice, and animals in different groups were treated by; a-) decellularized axolotl skin ECM (Axolotl group), b-) Symbios Perioderm acellular dermis scaffold (PerioDerm group), d-) Titanized mesh only (Control group); respectively. Wound tissues were harvested at time points: 7- and 30-days post-wounding to assess the scaffolds impact on wound healing. Wound healing was compared between the Axolotl, PerioDerm and Control groups using transillumination test and histological analyses, Results indicate that the decellularized axolotl skin ECM is well tolerated by mammalian models, as no immune rejection was observed. The axolotl group that received the decellularized Axolotl Skin ECM demonstrated high reepithelialization, cellular density, collagen content (in a porous pattern similar to intact skin), vascularization (angiogenesis) compared to PerioDerm and control groups. The presence of hair follicles was also observed in the axolotl group (which is not present in PerioDerm and control groups). Based on our results, the basic hypothesis appears to be correct in that an ECM scaffold from a strong regenerator seems to promote healing more efficiently in non-regenerating animals. However, further research should be conducted to confirm these findings.