Abstract. The aim of the present study was to investigate the therapeutic effect of deer antler extract on avascular necrosis of the femoral head (ANFH) induced by steroids, and to confirm that 11β-hydroxysteroid dehydrogenases (11β-HSD) are one of the targets of treatment with antler extract. A total of 30 rabbits were randomly divided into 5 groups (n=6): A control, ANFH, ANFH + antler (250 mg/kg), ANFH + antler (500 mg/kg) and ANFH + antler (1,000 mg/kg) group. Rabbits in the experimental groups were injected with methylprednisolone and horse serum to establish a steroid-induced ANFH (SANFH) model. Rabbits in the ANFH + antler (250 mg/kg), ANFH + antler (500 mg/kg) and ANFH + antler (1,000 mg/kg) groups were treated with intraperitoneal injection of 250, 500 or 1,000 mg/kg antler extract/day, respectively, for 60 days. Serum samples were then extracted to determine total cholesterol (CT) and triglyceride levels, treat osteoblasts, measure 11β-HSD (11β-HSD1) and 11β-HSD2 and alkaline phosphatase (ALP) levels and cellular apoptosis, and determine the proportion of osteoblasts in each phase of the cell cycle. Serum CT and triglyceride levels in SANFH rabbits significantly decreased as the concentration of antler increased (P<0.05). 11β-HSD1 levels in the femoral heads of SANFH rabbits and osteoblasts following treatment with antler-containing serum decreased as the concentration of antler used increased, whereas levels of 11β-HSD1 increased significantly (P<0.05). The proliferation of osteoblasts and ALP levels in osteoblasts increased as the antler concentration increased, whereas the number of osteoblasts in the G0/G1 phase decreased significantly (P<0.05). The current study demonstrated that treatment with antler extract has a therapeutic effect on ANFH induced by steroids in rabbits and may regulate the expression of 11β-HSD in femoral heads and osteoblasts, as well as promoting the proliferation of osteoblasts.
IntroductionOsteonecrosis of the femoral head (ONFH) is caused by the interruption of the blood supply to the femoral head or the pathological process of osteoblast death (1,2). Steroid-induced avascular necrosis of the femoral head (SANFH) is a type of non-traumatic ANFH and the most common type of femoral head necrosis. It occurs following the long-term use of adrenocorticotropic hormones (ACTH) or the use of high doses of ACTHs (3-5). The major clinical characteristics of ANFH include hip pain, limited mobility, lameness and a high disability rate, which negatively impact patient health and quality of life (6-8). It is estimated that ~50% of all ONFH cases are induced by ACTH (5,9,10). In China, there are 5-7.5 million patients with ONFH requiring treatment and the number of new ONFH cases was 150,000-200,000 in 1998, with the majority of cases diagnosed in young adults (11).Corticosteroids are widely used to treat several diseases, including asthma (12), nephritic syndrome (13) and leukemia (14), as they suppress inflammation, allergic reactions and the immune response. However, in the process of...