Participation of Engrailed 1 protein in differentiation of bone cells, skeletal growth, bone regeneration and osseointegration of titanium implants

• Grant number: 23/06782-2
• Support Opportunities: Research Projects - Thematic Grants
• Start date: April 01, 2025
• End date: March 31, 2030
• Field of knowledge: Health Sciences - Dentistry - Oral and Maxillofacial Surgery
• Principal Investigator: Adalberto Luiz Rosa
• Grantee: Adalberto Luiz Rosa
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Pesquisadores principais: Márcio Mateus Beloti
• Associated researchers: Emanuela Prado Ferraz ; Gary S Stein ; Gustavo Pompermaier Garlet ; Janet L Stein ; Luciana Oliveira de Almeida

Abstract

The engrailed 1 (EN1) protein belongs to a transcription factor family with DNA binding domain (homeobox) and alterations in its expression results in abnormalities in terms of development and ossification of sternum, phalanges and calvaria bones. Considering the relevance of En1 to osteogenesis, we hypothesized that this protein acts on molecular and cellular mechanisms that impacts skeletal growth, bone regeneration and osseointegration of titanium (Ti) implants. This research proposal is original as En1 has not been explored in bone regeneration and osseointegration, especially with loss and gain of function of En1 synthesized by osteoblasts and osteocytes. In this context, the general aim of this study is to investigate the participation of En1 in differentiation of bone cells, skeletal growth, bone regeneration and osseointegration of Ti implants. The project consists of four subprojects with eleven specific goals as follows.Subproject 1: Characterization of expression and effects of En1 on mesenchymal stem cells (MSCs) and osteoblast and osteocyte differentiation1.To characterize En1 expression in MSCs and during osteoblast and osteocyte differentiation.2To investigate the effects of En1 silencing and overexpression on MSCs and osteoblast and osteocyte differentiation.3.To investigate the cellular mechanisms, focused on fibroblast growth factor, Wnt, transforming growth factor beta and epigenetic regulation, involved in the effects of En1 on MSCs and osteoblast and osteocyte differentiation.Subproject 2: Evaluation of the participation of En1 expressed by osteoblasts and osteocytes on skeletal growth of mice4.To generate two lineages of mice with deletion of En1 in osteoblasts and osteocytes.5.To evaluate the effects of the deletion of En1 in osteoblasts and osteocytes on skeletal growth of mice.Subproject 3: Evaluation of the participation of En1 expressed by osteoblasts and osteocytes on bone regeneration6.To evaluate the bone regeneration of non-critical calvaria defects in mice with deletion of En1 in osteoblasts and osteocytes.7.To investigate the effects of MSCs injected into critical calvaria defects in mice with deletion of En1 in osteoblasts and osteocytes.8.To investigate the effects of MSCs with silenced and overexpressed En1 injected into critical calvaria defects of mice.Subproject 4: Evaluation of the participation of En1 expressed by osteoblasts and osteocytes on osseointegration of Ti implants9.To characterize the expression of En1 during differentiation of osteoblasts and osteocytes growth on Ti with nanotopography.10. To investigate the effects of En1 silencing and overexpression on differentiation of osteoblasts and osteocytes growth on Ti with nanotopography.11. To evaluate the osseointegration of Ti implants with nanotopography in mice with deletion of En1 in osteoblasts and osteocytes.The four subprojects will address from characterization of En1 expression by bone cells to its participation in osteogenesis processes, using advanced molecular and cellular biology tools and generating genetically modified animal models. In this scenario, we will contribute to the understanding of the molecular and cellular mechanisms involved in the effects of En1 on bone tissue and to the establishment of new treatments to promote bone regeneration and osseointegration in challenging sites, with applications in the areas of Oral and Maxillofacial Surgery, Periodontics, Implantology and Orthopedics. (AU)