2.6. Animal Experiment
OSTEOPOROSIS
The animal studies were performed with five-week-old female ICR mice (weight 20–22 g) obtained from Raonbio Inc. (Yongin, Republic of Korea). All experiments were performed according to the guidelines of the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health and approved by the Committee on the Care and Use of Laboratory Animals of Kyung Hee University (KHUASP(SE)-18-071). Mice were grown in the well-controlled room, maintaining a 12 h light/dark cycle at 20 ± 5 °C and 55 ± 15% humidity. Tap water and a standard chow diet were provided to all mice. After 1 week of adaptation, all mice (seven mice per group) were under surgery. After recovery and induction for 8 weeks, 17β-estradiol (E2) and Osteo-F were treated intraperitoneally and orally, respectively, for 8 weeks. Mice were assigned into six groups: (1) Sham, sham-operated normal control group, (2) OVX, ovariectomized negative control group, (3) E2, 10 μg/kg of E2-injected OVX positive control group, (4) Osteo-F 0.52 (0.52 mg/kg of Osteo-F-administrated OVX group), (5) Osteo-F 5.2 (5.2 mg/kg of Osteo-F-administrated OVX group), and (6) Osteo-F 52 (52 mg/kg of Osteo-F-administrated OVX group). All samples, including vehicle, E2, and Osteo-F, were treated once a day for 5 days per week. The administration dose of Osteo-F in mice was decided based on the human equivalent dose equation. After a total of 16 weeks of experimentation, 8 weeks for induction of osteoporosis, and 8 weeks for treatment, all mice were sacrificed.