ABSTRACT
Propolis, an apitherapic product widely employed in natural medicine, presents various biological properties, such as bactericidal and anti-inflammatory activities, but only few reports have looked at the Brazilian red propolis variety. Collagen films have been employed to improve wound healing and some studies have investigated the effect of natural products incorporated into these films. Thus, the aim of this study was to analyze the effect of collagen-based films containing red propolis on wound healing. Therefore, wounds performed in the back of rats were dressed with collagen-based films (G2), and collagen-based films containing red propolis (G3); undressed worked as control (G1). After 3, 7 and 14 days the animals were euthanized, and the wounds were microscopically evaluated. In 7 days, G3 showed switch of the inflammatory profile from acute into chronic, increased plasma cells differentiation, replacement of Type-III for type-I collagen fibers, and better architectural organization of those fibers. Furthermore, a slight tendency for a better epithelization was verified in G3, but it was not statistically significant. Also in 7 days, the microvessels count was higher in G1 than in G2 (p=0.000) and G3 (p=0.001), but similar between the last groups (p=0,15), whereas the microvessels perimeter was higher in G1 than in G2 (p=0.000) and G3 (p=0.002), but equivalent in G2 and G3 (p=0.175) in 14 days. In conclusion, the incorporation of Brazilian red propolis into collagen-based films was able to improve wound healing, probably by modulating the dynamics of the inflammatory evolution and collagen deposition process.
El propóleo es un producto apiterápico ampliamente usado en medicina natural, que presenta diversas propiedades biológicas, como actividad bactericida y anti-inflamatoria, pero pocos informes han examinado la variedad brasileña del propóleo rojo. Películas de colágeno han sido empleadas para mejorar la cicatrización de heridas y en algunos estudios se ha investigado el efecto de los productos naturales incorporados en estas películas. Así el objetivo de este estudio fue analizar el efecto de las películas a base de colágeno que contienen propóleo rojo en la cicatrización de heridas. Heridas realizadas en el dorso de ratas fueron revestidas con películas a base de colágeno (G2) y con películas a base de colágeno con propóleo rojo (G3), heridas sin revestimiento fueron utilizadas como control (G1). Después de 3, 7 y 14 días, las heridas fueron evaluadas microscópicamente. A los 7 días G3 mostró un cambio del perfil de la respuesta inflamatoria de aguda a crónica, con aumento de la diferenciación de las células plasmáticas, sustitución de fibras de colágeno tipo III por tipo I con mejora de la organización arquitectónica de estas fibras. Además, una ligera tendencia a una mejor epitelización se verificó en G3, pero no fue estadísticamente significativa. También a los 7 días, el conteo de microvasos fue mayor en G1 que en G2 (p=0,000) y G3 (p=0,001), pero similar entre los últimos grupos (p=0,15), mientras que el perímetro de los microvasos fue mayor en G1 que en G2 (p=0,000) y G3 (p=0,002), pero equivalente en G2 y G3 (p=0,175) en 14 días. En conclusión, la incorporación de la variedad brasileña de propóleo rojo en películas a base de colágeno fue capaz de mejorar la cicatrización de la herida, probablemente por la modulación de la dinámica de la evolución inflamatoria y del proceso de depósito de colágeno.
Subject(s)
Male , Animals , Rats , Wound Healing , Collagen Type I/therapeutic use , Occlusive Dressings , Propolis/therapeutic use , Collagen Type I/chemistry , Models, Animal , Propolis/chemistry , Rats, WistarABSTRACT
Aim: This study aimed to evaluate the effect of low-level laser therapy (LLLT) associated to mineral trioxide aggregate (MTA) on the alveolar bone repair process. Methods: Forty Wistar rats had the upper right incisor extracted and were assigned to 4 groups according to the treatment of the alveolar wound: G1 - no treatment (control group); G2 - sockets were filled with MTA; G2 - sockets were treated with LLLT(l780 nm, 40 mW, 16 J/cm2); and G4 sockets were treated with LLLT and filled with MTA. The animals were sacrificed 14 days after the surgical procedures. The maxillas were removed, fixed in formalin, decalcified in 0.5% nitric acid and processed histologically. Results: In G1, there was bone formation on the bottom of the socket, but it was not noticeable on the superficial areas, as well as the presence of an intense granulation tissue. In G2, the bone trabeculae were irregular and thin, and were associated with intense vascular hyperemia and chronic inflammation. In G3, there was substantial formation of thick interwoven osteocyte-rich trabecular bone, with an evident osteoblastic rimming. In G4, it was observed an intense deposition of thin irregular bone trabeculae, but vascular hyperemia was quite distinguishable. Conclusion: LLLT was the most successful treatment to improve alveolar bone repair.