Bin Fang1, Ying Li2, Chen Chen3, Qiushi Wei2, Jiaqian Zheng2, Yamei Liu3, Wei He2, Dingkun Lin4, Gang Li5, Yonghui Hou6, Liangliang Xu7. 1. Key Laboratory of Orthopaedics & Traumatology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, PR China; Laboratory of Orthopaedics & Traumatology, Lingnan Medical Research Center, Guangzhou University of Chinese Medicine, Guangzhou, PR China. 2. Key Laboratory of Orthopaedics & Traumatology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, PR China. 3. Departments of Diagnostics of Traditional Chinese Medicine, Guangzhou University of Traditional Chinese Medicine, Guangzhou, PR China. 4. The Department of Spinal Surgery, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, PR China. 5. Department of Orthopaedics & Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, PR China. 6. The Department of Spinal Surgery, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, PR China. Electronic address: hou_yonghui1982@hotmail.com. 7. Key Laboratory of Orthopaedics & Traumatology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, PR China; Laboratory of Orthopaedics & Traumatology, Lingnan Medical Research Center, Guangzhou University of Chinese Medicine, Guangzhou, PR China. Electronic address: xull-2016@gzucm.edu.cn.
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine has a long history of treating various bone diseases including osteoporosis and osteonecrosis etc. In clinical treatment, Huo Xue Tong Luo capsule (HXTL capsule) containing Peach kernel, Safflower carthamus, Angelica sinensis, Ligusticum wallichii etc, is one of the mostly used prescriptions for treating osteonecrosis of the femoral head (ONFH) with promising effects. OBJECTIVES: This study aims to identify the underlying molecular mechanism of how HXTL capsule exerts its function to ameliorate ONFH. MATERIALS AND METHODS: All femoral bone tissues were collected during surgeries. Rat bone marrow mesenchymal stem cells (rMSCs) were used. Quantitative real time PCR was used to check the relative expression levels of genes. ChIP assay was performed to evaluate the binding of H3K4me3 and H3K27me3 in Miat promoter. RESULTS: We showed that HXTL capsule promoted osteogenesis in rat MSCs as demonstrated by quantitative real time PCR and Alizarin Red S staining. Then we found silencing the endogenous lncRNA-Miat could promote osteogenesis of rMSCs. In addition, the ChIP assay showed that HXTL capsule significantly increased occupancy of H3K27me3 and decreased H3K4me3 in promoter regions of Miat, meaning HXTL capsule inhibited Miat expression through histone modifications. At last, by examining the femoral heads samples obtained from patients with ONFH during total hip arthroplasty surgery, we found the RNA level of hMiat in necrotic tissue was much higher than that of normal tissue. CONCLUSIONS: Taken together, our study shows that lncRNA-Miat might play an important role in pathogenesis of ONFH, and HXTL capsule can promote osteogenesis to ameliorate ONFH through inhibiting the transcriptional expression of Miat, at least partially.
ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine has a long history of treating various bone diseases including osteoporosis and osteonecrosis etc. In clinical treatment, Huo Xue Tong Luo capsule (HXTL capsule) containing Peach kernel, Safflower carthamus, Angelica sinensis, Ligusticum wallichii etc, is one of the mostly used prescriptions for treating osteonecrosis of the femoral head (ONFH) with promising effects. OBJECTIVES: This study aims to identify the underlying molecular mechanism of how HXTL capsule exerts its function to ameliorate ONFH. MATERIALS AND METHODS: All femoral bone tissues were collected during surgeries. Rat bone marrow mesenchymal stem cells (rMSCs) were used. Quantitative real time PCR was used to check the relative expression levels of genes. ChIP assay was performed to evaluate the binding of H3K4me3 and H3K27me3 in Miat promoter. RESULTS: We showed that HXTL capsule promoted osteogenesis in rat MSCs as demonstrated by quantitative real time PCR and Alizarin Red S staining. Then we found silencing the endogenous lncRNA-Miat could promote osteogenesis of rMSCs. In addition, the ChIP assay showed that HXTL capsule significantly increased occupancy of H3K27me3 and decreased H3K4me3 in promoter regions of Miat, meaning HXTL capsule inhibited Miat expression through histone modifications. At last, by examining the femoral heads samples obtained from patients with ONFH during total hip arthroplasty surgery, we found the RNA level of hMiat in necrotic tissue was much higher than that of normal tissue. CONCLUSIONS: Taken together, our study shows that lncRNA-Miat might play an important role in pathogenesis of ONFH, and HXTL capsule can promote osteogenesis to ameliorate ONFH through inhibiting the transcriptional expression of Miat, at least partially.