Ameliorating effect of bovine bone collagen peptide/astragalus polysaccharide combination on bone mineral density and its underlying mechanism

Abstract

Bone mineral density (BMD) reduction leads to osteoporosis. Polypeptides and polysaccharides are often used individually as supplements to improve BMD; however, the efficacy of their combined use relative to single components, as well as the underlying synergistic mechanisms, remains unclear. Therefore, this study screened bovine bone collagen peptide (BBCP) and Astragalus polysaccharide (APS) based on the theories of food-medicine homology and multi-target network regulation to investigate the synergistic ameliorative effects of a BBCP/APS combination (1 : 1, w/w) on BMD and the mechanisms underlying these effects. In vitro osteoblast models, in vivo ovariectomy (OVX) rat models, and network pharmacology analyses were employed to elucidate the underlying mechanisms. In vitro, compared with BBCP or APS alone, the BBCP/APS combination significantly enhanced osteoblast proliferation by 20.3 ± 5.80% and 22.9 ± 6.15%, respectively, and markedly upregulated osteogenic markers—alkaline phosphatase, osteocalcin, and type I collagen—relative to the model group (p < 0.01). In vivo, treatment with BBCP/APS (800 mg kg⁻¹) increased femoral BMD in OVX rats from 0.193 g cm⁻³ (model group) to 0.411 g cm⁻³ (p < 0.05) and significantly improved trabecular bone microarchitecture. Concurrently, network pharmacology analysis identified ADRA1A and ADRA2A as core targets and predicted the p38 MAPK pathway as the principal signaling pathway involved. Activation of the p38 MAPK pathway by BBCP/APS was further confirmed via RT-qPCR and western blot analyses. These findings demonstrate that the BBCP/APS combination synergistically enhances BMD, overcomes single-component limitations, and provides valuable insights for functional food development.