Saturated fatty acids negatively affect musculoskeletal tissues in vitro and in vivo

• Published in: Matrix biology plus Vol. 23; p. 100153
• Main Authors: Lin, Ryan T., Osipov, Benjamin, Steffen, Danielle, Chamberlin, Marin, Pathak, Suraj J., Christiansen, Blaine A., Paulussen, Kevin J.M., Baar, Keith
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.08.2024; Elsevier
• Subjects: Bone; Diet; Exercise; Muscle; Palmitate; Tendon; Muscle; Exercise; Bone; Diet; Palmitate; Tendon
• ISSN: 2590-0285; 2590-0285
• DOI: 10.1016/j.mbplus.2024.100153

•The saturated fatty acid palmitate deceased engineered human ligament mechanics and collagen content.•A 14-week high fat diet decreased the collagen content of the Achilles tendon resulting in a decrease in relative stength.•A high fat diet similarly decreased bone collagen content and bone mineral density and increased trabecular spacing.•In vitro, palmitic acid decreased procollagen synthesis in the first twenty-four hours after feeding.•A high fat diet decreases collagen synthesis in musculoskeletal tissues which may contribute to increased fracture and tendon/ligament injury rates. Fish oils rank among the world’s most popular nutritional supplements and are purported to have numerous health benefits. Previous work suggested that fish oils increase collagen production; however, the effect of fish oils on musculoskeletal health is poorly understood. Further, the divergent effects of omega-3 (Ω3FA) and saturated fatty acids (SFA) remains poorly understood. We tested the effects of Ω3FA and SFAs on in vitro-engineered human ligament (EHL) function. EHLs were treated with bovine serum albumin (BSA)-conjugated eicosapentaenoic acid (EPA, 20:5(n-3)), palmitic acid (PA, 16:0), or a BSA control for 6 days. EPA did not significantly alter, whereas PA significantly decreased EHL function and collagen content. To determine whether this was an in vitro artifact, mice were fed a control or high-lard diet for 14 weeks and musculoskeletal mass, insulin sensitivity, and the collagen content, and mechanics of tendon and bone were determined. Body weight was 40 % higher on a HFD, but muscle, tendon, and bone mass did not keep up with body weight resulting in relative losses in muscle mass, tendon, and bone collagen, as well as mechanical properties. Importantly, we show that PA acutely decreases collagen synthesis in vitro to a similar extent as the decrease in collagen content with chronic treatment. These data suggest that Ω3FAs have a limited effect on EHLs, whereas SFA exert a negative effect on collagen synthesis resulting in smaller and weaker musculoskeletal tissues both in vitro and in vivo.