Date of Award
Master of Science (MS)
Objective: The goal of this study was to investigate the effects of different dietary fatty acids in the context of diet-induced obesity on bone and cartilage in the humerus. It is known that obesity increases the severity of injury-induced osteoarthritis in the knee, however it is not fully understood what pathological changes have occurred due to diet alone1. Additionally, while it is known that shoulder osteoarthritis has a link to obesity, the alterations in this joint are incompletely described.
Methods: In order to examine diet-induced changes in both bone and cartilage, this research utilized mice that had been previously fed diets high in saturated fat (SF), omega-6 fatty polyunsaturated fatty acids (ω-6 PUFA) or omega-3 polyunsaturated fatty acids (ω-3 PUFA) for an earlier study1. Humeral heads were obtained for testing. Analysis for bone morphometry, bone mineral density, cartilage micro-scale mechanical properties using atomic force microscopy, and histological grading was performed.
Results: Differences in bone morphology and mineral density were seen between diet groups. The high-fat diets in general showed decreased bone quality with the ω-3 PUFA diet being partially protected. Micro-scale cartilage stiffness and overall modified Mankin scores showed no diet-dependence.
Discussion: This study showed that specific types of fatty acids differentially alter bone morphology and mineral density, with no observable changes in the articular cartilage. These findings suggest that in the shoulder, diet-induced obesity by itself may not be a risk factor for osteoarthritis, but may result in other musculoskeletal changes.
Spencer Lake Amit Pathak