Análise da expressão do IGF-1, TGF-β1 e PTHRP em calvária de ratos tratados com autoenxerto na presença e ausência de administração do análogo do hormonio de crescimento

• Autor(a) principal: Lopes, Amanda
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório do Centro Universitário Braz Cubas
• Texto Completo: https://repositorio.cruzeirodosul.edu.br/handle/123456789/2088
• topic: Hormônio do crescimento; Fatores de crescimento transformadores; Cicatrização; Osteogênese; IGF-1; PTHrP; CNPQ::CIENCIAS DA SAUDE::ODONTOLOGIA

Biomaterials taht may acts efficiently on tissue repair in the maxillofacial area remains limited within the surgical area. In this context researchers have been attracted to the systemic administration of drugs, and mainly hormonal analogues which may accelerate the bone repair and stimulate the osteoblastic activity. A hormone that interferes with the physiology of the bone repair process is growth hormone (GH). Although there are studies that demonstrate good prospects for GH and osteo (neo) genesis, data on the efficacy and safety of GH prolonged therapy in adults are scarce, and the major and alternative pathways corresponding to respectively IGF-1 and TGF expression β1, which act in a functionally antagonistic way, are not addressed in a significant way. The aim of this study was to investigate the immunohistochemical presence of IGF-1, TGF-β1 and PTHrP in the surgical beds treated with autogenous bone in the presence and absence of GH. Sixteen male rats were used in the present study, the animals were randomly assigned to two experimental groups, which consisted of a control group - which received autograft (OA), and another test, which in addition to the autograft received alternating doses of GH (transurgical irrigation using dose of 0.02 mL and applications in alternate day of 0.1 mL of GH analogue) (OA/ GH group). The results of the qualitative analysis of the histology showed that the Group (OA) presented regions suggestive of osteoconduction and bone neoformation, while the group (OA / GH) exhibited a defect filled by fibers of associated dense connective tissue, discrete chronic inflammatory process and areas compatible with mineral loss. These effects coincided with similarities of the IGF-1 protein for the groups but with discrepancies of TGF- β1 and PTHrP, which were exacerbated in the OH / GH groups. Here, it can be concluded that the use of the GH analogue leads to the expression of TGF- β1 and PTHrP proteins, which not only combine with osteolytic activity of the analyzed area, but also appear to have an effect that overlaps the IGF-1 pathway that is anabolics. Thus excess GH can lead to bone loss by an alternative mechanism via TGF- β1.