Orientin suppresses osteoclastogenesis and ameliorates ovariectomy-induced osteoporosis via suppressing ROS production

Yan Zheng; Xing Wang; Ya-Jing Pan; Xiao-Feng Shi; Lei Yang; Yong-Liang Lou

doi:10.1002/fsn3.3516

Orientin suppresses osteoclastogenesis and ameliorates ovariectomy-induced osteoporosis via suppressing ROS production

Food Sci Nutr. 2023 Jun 28;11(9):5582-5595. doi: 10.1002/fsn3.3516. eCollection 2023 Sep.

Authors

Yan Zheng^{1

2}, Xing Wang¹, Ya-Jing Pan¹, Xiao-Feng Shi¹, Lei Yang³, Yong-Liang Lou¹

Affiliations

¹ Wenzhou Key Laboratory of Sanitary Microbiology, Key Laboratory of Laboratory Medicine, Ministry of Education, School of Laboratory Medicine and Life Sciences Wenzhou Medical University Wenzhou China.
² Department of Endocrinology Affiliated Yueqing Hospital Wenzhou China.
³ Department of Orthopedic The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University Wenzhou China.

Abstract

The aberrant differentiation of osteoclasts is a key feature of the pathogenesis of osteoporosis, which has a devastating impact on human health. While the effects of Orientin (Ori) on osteoporosis, particularly on RANKL-stimulated osteoclast production and activation, remain still unclear, Ori has been found to display several biological activities, including antioxidant and anti-inflammatory. In this work, we investigated the possible pathways through which Ori suppressed RANKL-induced osteoclast development and showed for the first time that it does so. The macrophages from the bone marrow (BMMs) were cultivated and then treated with Ori after being stimulated with RANKL. Then, TRAP-positive multinucleated cells were counted, and F-actin ring analysis was used to assess Ori's impact on mature osteoclast development. In addition, dihydroethidium (DHE) staining was used to evaluate the impact of Ori on RANKL-induced reactive oxygen species (ROS). In addition, we performed western blotting and quantitative RT-PCR analysis to investigate probable causes of these downregulation effects. We discovered that Ori inhibits the creation of osteoclasts, the gene and protein expressions unique to osteoclasts, and the ROS production. By activating Nrf2 and other ROS-scavenging enzymes, Ori reduces intracellular ROS levels. The expression of the main transcription factor of osteoclast development, c-Fos, was downregulated together with NFATc1, CTSK, and NFATc2, thanks to Ori's inhibition of RANKL-induced NF-κB. Consistent with its in vitro antiosteoclastogenic action, Ori therapy in the ovariectomized (OVX) rat model was also able to restore bone mass and improve microarchitecture in the distal femurs. Together, our results demonstrate that Ori is a flavonoid molecule with therapeutic promise for bone illnesses associated with osteoclasts, such as osteoporosis.

Keywords: NF‐κB/Nrf2 pathway; Orientin; osteoclast; osteoporosis; reactive oxygen species.