The role of osteoprotegerin on the estradiol effects in energy homeostasis

• Grant number: 17/16696-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2017
• End date: September 30, 2018
• Field of knowledge: Biological Sciences - Physiology - General Physiology
• Principal Investigator: Lucila Leico Kagohara Elias
• Grantee: Marina Saavedra Azzem
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Energy homeostasis is regulated by hypothalamic neurons sensitive to circulating factors such as hormones and nutrients. Among the hormones, estradiol influences energy homeostasis, metabolism in adipocytes and energy expenditure. In addition, estradiol plays a key role in bone remodeling, reducing osteoclastogenesis. Bone remodeling involves the RANK/RANKL/OPG system, whose activity is influenced by different factors, including estrogens. A reduction of OPG mRNA expression in osteoblastic cells was observed in ovariectomized rats, suggesting a protective effect of estradiol in the bone tissue. Furthermore, the expression of estradiol receptors in adipose tissue was also shown, as well as the expression of OPG in differentiated 3T3-L1 adipocyte cells. Therefore, it is important to investigate the interplay of osteoprotegerin and estradiol in the energy homeostasis. Thus, the present project aims to investigate the participation of osteoprotegerin on estradiol effects in the control of energy homeostasis. To attain this purpose, food intake, energy expenditure and body weight will be assessed in female osteoprotegerin knockout (OPG-/-) or control (OPG+/+) mice will subjected to bilateral ovariectomy, with or without estradiol replacement, and treated with leptin under regular or high fat diet. (AU)