Protein bioactive complexes promote osteogenesis under microgravity environment

Area of Science:

• Biomedical Engineering
• Space Medicine
• Materials Science

Background:

• Space microgravity and cosmic radiation negatively impact bone mass.
• The mechanisms of space-induced bone loss, particularly the role of oxidative stress, are not fully understood.
• Existing treatments for bone loss have limitations in efficacy and side effects.

Purpose of the Study:

• To investigate the effects of simulated microgravity (SMG) on osteoblasts and identify underlying mechanisms.
• To develop and evaluate a novel antioxidant delivery system for mitigating space-induced bone loss.
• To assess the potential of this new treatment for maintaining bone health in space.

Main Methods:

• Simulated microgravity (SMG) was used to induce bone loss in MC3T3/MG63 osteoblasts and zebrafish scales.
• Zein nanocages loaded with a chimeric antioxidant cocktail (ZNAC) were designed and characterized.
• The efficacy of ZNAC in reducing reactive oxygen species (ROS), preserving cytoskeletal integrity, and promoting osteogenesis was evaluated.
• Osteogenic gene expression, alkaline phosphatase (ALP) activity, and calcification were measured.

Main Results:

• SMG induced ROS production, cytoskeletal damage, and downregulated osteogenic genes in osteoblasts.
• ZNAC demonstrated excellent stability, biocompatibility, and antioxidant properties.
• ZNAC effectively reduced SMG-induced ROS, preserved cytoskeletal integrity, and enhanced osteogenic markers in cell cultures.
• In zebrafish scales, ZNAC promoted regeneration, increased osteogenic gene expression, and improved calcification.

Conclusions:

• ZNAC is a promising therapeutic candidate for preventing and treating space-induced bone loss.
• The developed zein nanocage system effectively delivers antioxidants to combat oxidative stress.
• This approach holds potential for maintaining astronaut musculoskeletal health during long-duration space missions.