Diets Differently Affect Bone Health: Murine Models

Area of Science:

• Bone Biology
• Nutritional Science
• Skeletal Physiology

Background:

• Bone remodeling is crucial for maintaining skeletal health.
• Dietary factors, including fat content, significantly influence bone metabolism.
• Western diets (WD) and ketogenic diets (KD) are increasingly prevalent, necessitating an understanding of their skeletal effects.

Purpose of the Study:

• To investigate the impact of varying dietary fat content, including normal (ND), Western (WD), and ketogenic (KD) diets, on mouse femur microarchitecture.
• To assess the effects of diet transitions on bone remodeling markers, specifically osteoclast and osteoblast activity.
• To evaluate the potential for dietary interventions to mitigate diet-induced bone changes.

Main Methods:

• Mice were fed ND or WD for 16 or 20 weeks, followed by combinations with KD for 20 weeks.
• Femurs were analyzed using micro-computed tomography (Micro-CT) to assess bone volume fraction (BV/TV), trabecular thickness, and cortical bone thickness.
• Histological analyses, including Masson staining, were performed to quantify osteoclast and osteoblast numbers and evaluate bone structure.

Main Results:

• Western diets significantly reduced cortical bone thickness compared to normal diets.
• Ketogenic diets, especially in combination with Western diets, showed a trend toward decreased trabecular bone volume fraction and thickness.
• Histological analysis revealed increased osteoclast numbers and decreased osteoblast numbers in specific dietary groups, indicating altered bone remodeling.

Conclusions:

• Transitioning from a high-fat diet to a normal diet may partially restore cortical bone health.
• Ketogenic diets appear to exert detrimental effects on trabecular bone, potentially exacerbating diet-induced bone loss.
• Dietary fat content and composition play a critical role in maintaining bone health, with implications for nutritional strategies.