Targeting osteoblastic 11β-HSD1 to combat high-fat diet-induced bone loss and obesity

Area of Science:

• Endocrinology
• Metabolic Disorders
• Bone Biology

Background:

• Excessive glucocorticoid (GC) action is implicated in metabolic disorders.
• Skeletal GC signaling influences obesity and bone loss, particularly in high-fat diet (HFD) models.
• Osteoblasts play a role in GC metabolism and signaling within bone.

Purpose of the Study:

• To investigate the role of osteoblastic 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in high-fat diet-induced obesity and bone loss.
• To determine the mechanistic link between 11β-HSD1 in osteoblasts and metabolic dysfunction.
• To evaluate the therapeutic potential of inhibiting osteoblastic 11β-HSD1.

Main Methods:

• Utilized male mice fed a high-fat diet (HFD).
• Generated osteoblast-specific 11β-HSD1 knockout mice.
• Administered a bone-targeted 11β-HSD1 inhibitor.
• Assessed bone parameters, glucose metabolism, and obesity markers.

Main Results:

• Elevated osteoblastic 11β-HSD1 expression correlated with obesity and bone loss in HFD-fed mice.
• Osteoblast-specific 11β-HSD1 knockout mice were resistant to HFD-induced metabolic and bone deficits.
• Inhibition of osteoblastic 11β-HSD1 enhanced bone formation, improved glucose handling, and reduced obesity.
• Mechanistically, 11β-HSD1 was found to restrain osteoblast glucose uptake and osteogenic activity.

Conclusions:

• Osteoblastic 11β-HSD1 is a key mediator of high-fat diet-induced obesity, bone loss, and impaired glucose metabolism.
• Targeting 11β-HSD1 within osteoblasts represents a promising therapeutic strategy for metabolic and bone disorders.