Improvement of Glucose Intolerance in Asian-Type Diabetes Model Mice Using Pentadecyl, Pentadecanoic Acid-Based Triglyceride

<jats:p>Even-chain saturated fatty acid concentrations are associated with an increased risk of coronary heart disease, whereas oddchain saturated fatty acid concentrations, such as pentadecanoic acid (15:0) and heptadecanoic acid (17:0), are associated with a decreased risk. Similarly, even-chain saturated fatty acids are positively associated with type 2 diabetes (T2D), whereas odd-chain saturated fatty acids are thought to be inversely associated with T2D. We purified pentadecyl, pentadecanoic acidbased triglycerides from Aurantiochytrium limacinum, a type of marine microalgae, and demonstrated the effect of pentadecyl on insulin secretion both in vitro and in vivo. Pentadecyl increased the cell viability of immortalized mouse pancreatic beta cells in a dose-dependent manner and induced high glucose-stimulated insulin secretion in the cells. Pancreatic beta cellspecific CDKAL1-deficient mice, a model of Asian-type T2D, were given pentadecyl with a low- or high-fat diet for 9 weeks, and glucose tolerance tests were performed. Pentadecyl improved the glucose intolerance of the mice and decreased the expressions of ER stress-related genes in the islets of the mice. These results suggest that pentadecyl can improve insulin secretion through the reduction of ER stress in patients with Asian-type T2D.</jats:p>