Strontium chelate with Achyranthes bidentata polysaccharide as a carrier promotes bone regeneration through mediating gut-liver-bone axis: The TD chicken model

This study investigates the effect of Achyranthes bidentata polysaccharide-strontium (ABPS-Sr) chelate on tibial dyschondroplasia (TD) in broilers and its underlying mechanisms. TD is a prevalent leg disorder in commercial broilers characterized by reduced angiogenesis in the tibial growth plate (TGP), with limited effective interventions in modern poultry farming. ABPS-Sr was synthesized as a novel chelate, leveraging Achyranthes bidentata polysaccharide to target lower limb bone repair by delivering osteogenic and angiogenic strontium. In a thiram-induced TD broiler model, ABPS-Sr significantly improved growth performance and tibial bone microstructure, while promoting angiogenesis in the TGP. Mechanistically, ABPS-Sr promoted angiogenesis within the TGP by upregulating the expression of vascular endothelial growth factors and restored osteogenic differentiation by activating the ITGB1/FAK/PI3K/AKT1 signaling pathway. Additionally, ABPS-Sr regulated gut microbiota composition, restored intestinal barrier function, and corrected hepatic lipid metabolism disorders, particularly by reducing plasma glycerophospholipid (e.g., phosphatidylcholine) accumulation that exerts negative effects on bone health. Fecal microbiota transplantation experiments further confirmed that the gut microbiota is essential for mediating the bone-protective effects of ABPS-Sr. Collectively, these findings reveal that ABPS-Sr effectively alleviates TD through direct actions on bone repair and angiogenesis as well as by orchestrating recovery along the gut-liver-bone axis, which provides a promising nutritional intervention strategy for improving poultry bone health.