BIOL 3051 Lecture Notes - Lecture 7: Medroxyprogesterone Acetate, Bone Resorption, Aromatase Inhibitor
20 Apr 2020
School
Department
Course
Professor
Document Summary
Glucocorticoids (prednisone) lead to an increase in bone resorption and decrease bone formation, this is dose and duration dependant; rapid bone loss within the first 6-12 months of therapy at prednisone doses of more than 7. 5mg/day. Note that glucocorticoids enhance the apoptosis of osteoblasts, reduces the testosterone and estrogen concentrations of individuals, and can create a negative calcium balance via calcium excretion and reduced absorption. It can also decrease osteoprotegerin and increase rankl, causing osteoclasts to be generated and increase bone resorption. Anti-androgens (bicalutamide) can lead to hypogonadism, which in turn can lead to osteoporosis (especially in men). Due to the anti-testosterone effects (note that testosterone helps to increase and maintain muscle mass, as well as maintain bone density), it causes a decrease in bone mineral density. Aromatase inhibitors (letrozole) are anti-estrogen agents and estrogen plays a major role in maintaining bone density by preventing calcium resorption and increasing levels of bone formation.
