Objective To investigate the effect of Xianlinggubao capsule on the expression of H3K36me3 (histone H3 lysine 36 trimethylation), H3K9me3 (histone H3 lysine 9 trimethylation), and JMJD2A in bone tissues of ovariectomized rats. Methods Twenty-four female SD rats were randomly divided into four groups: blank control group, negative control group, experimental group, and positive control group, with 6 rats in each group. The rats in the blank control group retained bilateral ovaries and only some fat beside the ovaries were excised. Osteoporosis model was established in the other 3 groups of rats by resection of bilateral ovaries. One week after the operation, rats in the experimental group received 30.85 mg/100 g of Xianlinggubao capsule. Rats in the positive control group received 11.7 mg/100 g of Fumeijia. Rats in the blank control and the negative control group received the same volume of distilled water at the same time. After 3 months of continuous administration, HE staining was used to observe the microstructure of bone; RT-PCR was used to detect the mRNA expressions of histone H3 and JMJD2A. Western blotting (WB) was used to detect the protein expressions of H3K36me3, H3K9me3, and JMJD2A. Results The bone microstructure in the blank group, experimental group, and positive control group was superior to that in the negative control group. The expression of JMJD2A in bone tissue of blank group, experimental group, and positive control group was significantly higher than that in the negative control group (P<0.05). The expression of histone H3 mRNA in blank group, experimental group, and positive control group was lower than that in the negative control group (P<0.05). The protein expressions of H3K9me3 and H3K36me3 in the blank group, experimental group and positive control group were lower than that in the negative control group (P<0.05). Conclusion Xianlinggubao capsule relieves osteoporosis symptoms in ovariectomized rats. Its mechanism may be related to the increase of JMJD2A expression in bone tissues of ovariectomized rats and the inhibition of H3K36 me3 and H3K9 me3 expression. |