Single-cell transcriptomic analysis reveals AP-1 downregulation remodels bone marrow environment and contributes to osteopenia in ovariectomized mice

AP-1 downregulation drives estrogen deficiency-related osteopenia by disrupting bone marrow homeostasis, primarily through excessive B cell expansion and elevated osteoclastogenic signaling. Targeting B cell proliferation via IL-7 blockade presents a potential therapeutic strategy for mitigating osteoporosis in estrogen-deficient conditions.