An anti-aging dietary supplement inhibits dipeptidyl peptidase-4 (DPP-4) and arginase in vitro and improves quality of life factors of middle-aged adults

Abstract

Somatopause is the progressive and age-related decline of growth hormone (GH) production due to changes in hypothalamic-pituitary axis signaling and results in typical physiological changes associated with the aging process. Dipeptidylpeptidase-4 (DPP-4) influences hypothalamic-pituitary axis signaling and reduces GH production and secretion. Since DPP-4 concentrations increase with age, we investigated the anti-aging potential of several botanical ingredients, including noni fruit juice, by evaluating their abilities to inhibit this enzyme in vitro. We discovered that a blend of these botanical ingredients synergistically inhibited DPP-4 by up to approximately 99%. We subsequently formulated an anti-aging dietary supplement with this blend of botanical ingredients by adding amino acids (L-arginine, L-Lysine, citrulline and beta-alanine), gamma-aminobutyric acid (GABA), flax seed oil and several nutrients. The supplement was evaluated for anti-arginase activity in vitro, as the expression of this enzyme also increases with age. A concentration-dependent reduction in arginase activity was observed. The dietary supplement was also provided to three men and one woman, ages 56 to 62, with relevant but disparate medical histories. Following short-term ingestion of the supplement, these volunteers were interviewed to ascertain any changes in health status. All reported positive improvements in at least one quality of life factor, which included more restful sleep, reduced musculoskeletal discomfort, increased energy, improved physical stamina and better skin quality. These initial findings suggest that the anti-aging dietary supplement can mitigate declines in quality of life associated with aging by reducing DPP-4 and arginase activities, thereby supporting healthy GH production and endothelial nitric oxide production.