RESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Hancornia speciosa Gomes, commonly known as Mangabeira, is a Brazilian native fruit tree belonging to the Apocynaceae family. In folk medicine, the latex obtained from Mangabeira's trunk has been used as an adjunct therapy for bone fractures. Few pharmacological studies on the Hancornia speciosa latex have been developed and despite its popular use for bone healing there is no data about its biological effect on bone. AIM OF THE STUDY: The present study aimed to investigate the osteogenic potential of Hancornia speciosa latex in rat calvaria, as well as its phytochemical profile. MATERIALS AND METHODS: A neutral gel composition containing 5% latex was topical applied to a critical size bone defect and over intact calvaria of rats. Areas of newly formed bone on the borders of the defect and of calvaria periosteum were quantified, as well as the percentage of BrdU-positive cells and total cells in the periosteum at different periods of time after latex application. The cytotoxicity of the latex aqueous phase was evaluated in rat calvarial cells in vitro by MTT assay and its phytochemical profile was investigated by ESI-MS/MS. RESULTS: The area of newly formed bone on the borders of the calvaria defect was larger in rats that received latex at 15 and 30 days of healing. After 3 days of latex application over the intact calvaria, the periosteum area was increased and newly formed bone was observed after 5 and 11 days. There was also an increase in periosteum cell proliferation and population followed latex application on calvaria (p<0.05). The latex aqueous phase limited rat calvarial cell viability in vitro in concentrations larger than 0.6mg/mL. Chlorogenic acid and naringenin-7-O-glucoside were identified in the latex aqueous phase, along with catechin and procyanidin compounds. CONCLUSION: There was a stimulus for periosteum cell proliferation and bone formation when Hancornia speciosa latex was topically applied on rat calvaria. In addition, chlorogenic acid and naringenin-7-O-glucoside present in Hancornia speciosa latex may contribute to its effects on bone formation.
Assuntos
Apocynaceae/química , Látex/farmacologia , Osteogênese/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Crânio/efeitos dos fármacos , Animais , Biflavonoides/farmacologia , Brasil , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácido Clorogênico/farmacologia , Flavanonas/farmacologia , Glucosídeos/farmacologia , Masculino , Medicina Tradicional/métodos , Periósteo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Ratos , Ratos WistarRESUMO
MMP-9 and MMP-2 are metalloproteinases which degrade the denatured collagen fibers. However, there is no report about roles of these MMPs in the odontogenic region of the adult rat incisor tooth under different eruption conditions. Male Wistar rats were divided in a normofunctional group (NF) in which their lower teeth remained in a normal eruption. In a hypofunctional group (HP) rats underwent shortening of their lower left incisor tooth every 2 days during 12 days. The eruption rate as well as the expression and activities of MMP-9 and MMP-2 were evaluated using imunohistochemistry and zymography. Although the shortening increased the eruption rate, no changes in the MMP-9 and MMP-2 were observed. We conclude that in adult rats, in opposite to development of tooth, the MMP-9 and MMP-2 present in the odontogenic region does not seem to play a direct role in the remodeling matrix, even after post-shortening procedures which to lead an acceleration of the eruption process in the incisor.
Assuntos
Incisivo/crescimento & desenvolvimento , Incisivo/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Odontogênese , Ameloblastos/metabolismo , Animais , Papila Dentária/citologia , Papila Dentária/metabolismo , Saco Dentário/citologia , Saco Dentário/metabolismo , Ensaios Enzimáticos , Masculino , Odontoblastos/metabolismo , Ratos , Ratos Wistar , Erupção DentáriaRESUMO
MT1-MMP and TIMP-2 are well known for their roles in remodelling of extracellular matrix components. However, reports are emerging on the involvement of these molecules in cell kinetics. In the rat incisor tooth, a shortening treatment increases the eruption and cell proliferation rates. However, the role of MT1-MMP and TIMP-2 proteins in these processes is still to be evaluated. Male Wistar rats were divided in two groups. In the normofunctional group (NF) the lower teeth of the rats remained in a normal eruption process. In the hypofunctional group (HP) rats their lower left incisor tooth was shortened every 2 days during 12 days. The eruption rate was estimated during the shortening period and MT1-MMP, TIMP-2 and Ki-67 protein expression from the odontogenic region was measured after the treatment. In HP groups an increase in eruption rate, and in MT1-MMP/TIMP-2 and Ki-67 expression were observed. We conclude that there is a relationship between the increase in eruption rate, and in levels of MT1-MMP, TIMP-2 and Ki-67 in the HP group. This suggests that MT1-MMP and TIMP-2 may have some role in cell proliferation during the eruption of the rat incisor tooth.