Manganese Deficiency and Mn₂O₃ Nanoparticles Supplementation Disrupt Bone Remodeling and Mineral Matrix Maturation in...

Area of Science:

• Biochemistry
• Bone Biology
• Nutritional Science

Background:

• Manganese is essential for bone health and metabolism.
• The comparative effects of manganese macroparticles and nanoparticles on bone remodeling are not well understood.

Purpose of the Study:

• To investigate the impact of dietary manganese deficiency on bone remodeling and metabolism.
• To compare the effects of manganese macroparticles (MnCO₃) and manganese oxide nanoparticles (Mn₂O₃NPs) on bone health in rats.

Main Methods:

• Wistar rats were fed a standard diet, a manganese-deficient diet, or a diet supplemented with Mn₂O₃NPs for 12 weeks.
• Bone-related markers (enzymes, cytokines, hormones, collagen turnover) and gene expression were analyzed in femur and blood samples.

Main Results:

• Manganese deficiency significantly reduced plasma and femur levels of key bone formation and resorption markers, including BALP, TRAP5b, IFN-β, and collagen turnover markers.
• Supplementation with Mn₂O₃NPs altered plasma levels of IFN-β and IFN-γ, and reduced femur BALP and calcitonin.
• Mn₂O₃NPs treatment decreased the RANKL:OPG ratio and increased Sp7 and Ctsk gene expression, suggesting complex effects on bone remodeling.

Conclusions:

• Dietary manganese deficiency leads to suppressed bone turnover and disrupted mineral metabolism.
• Replacing standard manganese with Mn₂O₃ nanoparticles did not demonstrate clear benefits for bone remodeling and warrants further investigation due to observed imbalances.