A research team at Shinshu University, led by Associate Professor Takakazu Mitani, has identified pterostilbene—a naturally occurring polyphenol found in blueberries, grapes, and other berries—as a dietary compound that can influence fat metabolism within skeletal muscle cells. The study, published in Volume 83 of the Food Bioscience journal on September 1, 2026, demonstrates that pterostilbene reduces abnormal fat accumulation in cultured C2C12 mouse skeletal muscle cells without impeding normal muscle growth and differentiation. The compound achieves this by increasing the expression of genes involved in fatty acid oxidation and enhancing the release of glycerol, indicating the breakdown of stored lipids for energy utilization.
The researchers further elucidated the molecular mechanism behind pterostilbene’s effects, discovering that it stabilizes peroxisome proliferator-activated receptor delta (PPARδ) by preventing its degradation through the ubiquitin-proteasome pathway. This stabilization leads to increased PPARδ transcriptional activity, thereby boosting the activity of genes associated with lipid metabolism. Unlike many experimental compounds that directly activate PPARδ, pterostilbene enhances the availability of the PPARδ protein within cells, thereby promoting fatty acid oxidation and limiting lipid accumulation. While the findings establish a scientific framework for developing functional foods and nutritional supplements targeting muscle fat metabolism, the researchers emphasize that additional in vivo research is necessary to determine the compound’s efficacy and safety in animal models and humans before potential nutritional or pharmaceutical applications can be pursued. Source