Combined high-fat-resveratrol diet and RIP140 knockout mice reveal a novel relationship between elevated bone mitochondrial content and compromised bone microarchitecture, bone mineral mass, and bone strength in the tibia

Abstract

Scope: While resveratrol (RSV) is associated with the prevention of high-fat (HF) diet-induced insulin resistance, the effects on bone health combined with an HF-diet is unknown. Therefore, we determined the effect of RSV on bone microarchitecture in the presence of an HF-diet, while also elucidating molecular adaptations within bone that could contribute to bone health status.

Methods and results: Male C57BL6 mice were provided control (10% fat) or HF-diet (60% fat) in the presence or absence of RSV for 12 weeks. While RSV prevented HF diet-induced glucose intolerance, HF-RSV compromised tibial microarchitecture, mineral mass, and strength. The compromised outcomes following HF-RSV corresponded with higher markers of osteoclast-activation and bone-resorption (decreased OPG/RANKL ratio; increased cathepsin K), as well as higher markers of tibial mitochondrial content. A molecular model of elevated mitochondrial content (RIP140 knock out (KO) mice) was utilized to determine proof-of-principle that increasing mitochondrial content coincides with decrements in bone health. RIP140 KO mice displayed higher markers of mitochondrial content, and similar to HF-RSV, had compromised bone microarchitecture, lower BMD/strength, and higher markers of osteoclast-activation/bone-resorption.

Conclusion: These data show that in the presence of an HF-diet, RSV negatively alters bone health, a process associated with increased mitochondrial content and markers of bone resorption.

Keywords: Bone health; Bone turnover; Mitochondria; Resveratrol; Type 2 diabetes.