FSH aggravates bone loss in ovariectomised rats with experimental periapical periodontitis

Periapical bone loss is one of the prominent pathological and clinical features of periapical periodontitis. Previous studies have demonstrated that follicle-stimulating hormone (FSH) could directly affect skeletal remodelling by stimulating the formation and the function of osteoclasts in vitro and in vivo. However, the effect of FSH on periapical bone loss remained to be fully elucidated. In the current study, a rat model was established in order to verify the effect of FSH in experimental periapical lesions. It was identified that FSH aggravated the bone loss of periapical lesions. In addition, RANKL-, TRAP-, TNF-α- and IL-1β-positive cells were increased significantly in FSH-treated groups, which indicated that the function of FSH in bone loss may be mediated through the increasing activity of osteoclasts and the increased secretion of inflammatory cytokines. The results of the current study suggested that FSH, independent of oestrogen, may aggravate periapical bone loss by FSH receptors, which may serve an important role in the immune and inflammatory response of the host to root canal and periradicular infection during menopause.