Crab shell polypeptides enhance calcium dynamics and osteogenic activity in osteoporosis

Area of Science:

• Biochemistry
• Biomaterials
• Bone Biology

Background:

• Osteoporosis (OP) is a global health issue characterized by bone loss and increased fracture risk.
• Current OP treatments have limitations including adverse effects, high costs, and limited long-term efficacy.
• Novel therapeutic agents are needed to address the challenges of osteoporosis management.

Purpose of the Study:

• To identify and characterize snow crab shell-derived polypeptides (SCSP) as a potential osteoprotective agent.
• To investigate the efficacy of SCSP in an ovariectomized (OVX) mouse model of osteoporosis.
• To elucidate the molecular mechanisms underlying SCSP's effects on bone metabolism.

Main Methods:

• SCSP were extracted and characterized.
• An OVX mouse model was used to assess SCSP's in vivo effects on bone microstructure, histomorphometry, and serum bone turnover markers.
• In vitro studies evaluated SCSP's impact on osteogenic and adipogenic differentiation in mesenchymal stem cells (MSCs) and preosteoblasts using various assays and molecular analyses.

Main Results:

• SCSP treatment significantly improved bone mineral density, restored trabecular architecture, and preserved bone integrity in OVX mice.
• SCSP demonstrated no detectable systemic toxicity.
• Molecular analyses revealed that SCSP promotes osteogenesis by upregulating cell cycle regulators and motor protein pathways while suppressing pro-inflammatory signaling, re-establishing osteoblast-osteoclast balance and homeostasis.

Conclusions:

• SCSP is a potent osteoprotective agent with potential as a natural therapeutic for osteoporosis.
• SCSP acts through a dual mechanism of promoting osteogenesis and suppressing adipogenesis.
• These findings provide mechanistic insights for developing future bone-targeted interventions.