Desmethoxyyangonin, a Potent Cannabinoid Receptor 2 Agonist, Alleviates Bone Loss in Ovariectomized Mice via Dual Regulation of Osteoblast and Osteoclast Function

Osteoporosis is a prevalent skeletal disorder characterized by imbalanced bone remodeling, leading to excessive bone loss. Cannabinoid receptor 2 (CB2) has emerged as a promising therapeutic target in bone metabolism due to its peripheral expression and dual regulation of osteoblast and osteoclast activity. Desmethoxyyangonin (DMY) has demonstrated CB2 agonist activity, yet its therapeutic efficacy and molecular mechanisms in bone remain incompletely understood. Here, we investigated the anti-osteoporotic effects of DMY and its mechanistic insight on CB2 signaling. An ovariectomized (OVX) mouse model was used to assess the in vivo effects of DMY on trabecular bone microarchitecture and biomechanical properties. The impact of DMY on osteoblast and osteoclast differentiation was examined in vitro using MC3T3-E1 cells and bone marrow-derived macrophages (BMMs), respectively. Molecular docking and molecular dynamics simulations were conducted to investigate the potential interactions between DMY and CB2. Untargeted metabolomics was performed to explore metabolic alterations associated with DMY treatment. Western blot studies evaluated key osteogenic and signaling markers. DMY treatment significantly restored bone mineral density and improved trabecular microarchitecture. In vitro, DMY promoted osteoblast differentiation and mineralization while concurrently suppressing osteoclast formation and function. Pharmacological blockade of CB2 with its antagonist (SR144528) abrogated DMY's effects on both cell types, indicating CB2-mediated action. Molecular docking and dynamics simulations predicted a stable interaction between DMY and CB2. Untargeted metabolomics revealed DMY-induced shifts in metabolic pathways related to bone remodeling. Mechanistically, DMY upregulated osteogenic markers and activated PI3K/Akt and Wnt/β-catenin signaling cascades. Collectively, these findings demonstrate that DMY exerts bone-protective effects via CB2-dependent modulation of bone formation and resorption, offering a dual-target strategy for osteoporosis intervention.