Intermittent Fasting Improves Bone Fracture Healing in Obese Mice

Voiceover

Presenter(s)

Aaron Tran

Abstract or Description

Obesity is a risk factor for delayed fracture healing and fracture nonunion, which results in pain, disability, and increased medical costs. Studies on fractures in obese mice have revealed a reduction in cartilage and bone tissues crucial for endochondral new bone formation within the fracture callus, particularly noticeable at 21-day mark post-fracture, indicating delayed healing. Intermittent fasting (IF) is a dietary regimen known for its metabolic benefits, which have been shown to alleviate obesity-related pathologies.

This study aims to investigate whether IF can mitigate the adverse effect of obesity on fracture healing by enhancing callus cartilage content and promoting new bone formation. For this study, 18-week-old high-fat diet (HFD) fed obese male mice were divided into two groups: 1) continued free access to HFD (HFD-Adlib), and 2) subjected to every-other-day access to HFD (HFD-IF). After four weeks, mice underwent unilateral tibial fracture surgery. At 21 days post-surgery, fracture calluses were assessed using micro-CT and histology. Micro-CT scans of the tibiae were analyzed using a Scanco scanner and software was used for manual segmentation to measure bone volume/total volume of the calluses. Tissue segmentation and measurement of cartilage area within the calluses were performed using Qu Path software. Results were compared among HFD-Ad lib, HFD-IF, and a group of non-obese mice on a control diet.

Micro-CT and histology analyses revealed deteriorated callus mineralization and reduced cartilage content in HFD-Ad lib mice, which were restored to levels comparable to the control group in HFD-IF mice.

In conclusion, our study confirms that IF can enhance impaired fracture healing in obese mice and warrants further investigation as a potential strategy to mitigate the risk of fracture nonunion in obese patients.

Mentor

Dr. Honey Hendesi