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Updated: Jun 20, 2026

Estrogen-Like Effect of Bazi Bushen Capsule in Ovariectomized Rats
Published on: April 7, 2023
M1 macrophage-conditioned medium and Vitex agnus-castus effects on bone tissue organization in ovariectomized rats:
Sayuri Poli Suguimoto1, Maria Carolina Coelho1, Laysa Tauana Rosado da Silva1
1Bone Research Laboratory, Department of Basic and Oral Biology, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, SP, Brazil.
Background:
Bone repair is a highly coordinated process regulated by the local microenvironment, in which macrophage polarization plays a key role, particularly under estrogen-deficient conditions. Natural immunomodulatory compounds, such as Vitex agnus-castus (monk's pepper; VAC), may influence macrophage-mediated responses and exert osteoprotective effects. This study investigated how M1 macrophage-conditioned medium (CM) and VAC, alone or in combination, influence bone tissue organization and osteogenic activity in ovariectomized (OVX) rats.
Methods:
Ovariectomized and SHAM rats received M1 macrophage-conditioned medium in calvarial defects and/or oral Vitex agnus-castus for 60 days. Bone neoformation, osteocyte density, and collagen organization were evaluated histomorphometrically. In vitro, mesenchymal stem cells were assessed for viability, alkaline phosphatase activity, and mineralization.
Results:
Despite systemic osteoporotic changes, OVX and SHAM groups showed similar bone formation patterns in calvarial defects, suggesting site-specific responses to estrogen deficiency. However, CM treatment significantly enhanced osteocyte density and improved the structural organization of newly formed bone in OVX animals. In contrast, VAC alone had limited effects on tissue architecture, while the combined treatment increased osteocyte numbers without improving overall bone organization. Cytokine profiling confirmed a pro-inflammatory macrophage phenotype, supporting a microenvironment-driven mechanism. In vitro, CM enhanced cell viability, alkaline phosphatase activity, and mineralization in OVX-derived cells, whereas VAC showed modest effects. The combined treatment underperformed compared to CM alone.
Conclusions:
These findings indicate that macrophage-derived factors modulate the bone microenvironment, promoting structurally improved tissue repair under osteoporotic conditions and highlighting the complex interplay between immune signaling and bone tissue organization.
