Effect of green tea extract on bone healing in ovariectomized rats

Abstract

Osteoporosis is a disease that affects a great part of world population and is characterized by bone weakening and risk of fracture due to decreased estrogen levels and accumulation of free radicals by oxidative stress, besides poor diet and physical inactivity. Green tea is an inexpensive beverage, which contains epigallocatechin gallate, a flavonoid with high antioxidant and anti-inflammatory potential. The aim of this study is to evaluate the effect of green tea extract (GTE) on bone repair of defects performed in calvaria of ovariectomized rats. Animals will receive doses of 50 mg/kg body weight of GTE by oral gavage. After 60 days of ovariectomy, bone defects will be created (5 mm wide) and after 31 days, the animals will be sacrificed for collection and fixation of calvaria fragments. The samples will be histologically processed and histological sections will be stained with Hematoxylin-Eosin and Masson's Trichrome. The amount of newly formed bone will be examined by differential point counting method to determine the relative percentage of newly formed bone area in the following groups: control/sham group (C); ovariectomized (OVX); ovariectomized + GTE administration after ovariectomy and bone defect (OVXC); ovariectomized + GTE administration only after the bone defect (OVXCD). Data obtained will be analyzed by adequate statistical softwares, and the significance set at 5%.