Liquid Extract from the Bark of Magnolia officinalis Rejuvenates Skin Aging Through Mitochondrial ROS Reduction

Reactive oxygen species (ROS) are a major cause of skin aging, leading to oxidation and cleavage of collagen that supports skin structure. Previous studies have demonstrated that Magnolia officinalis var. officinalis (M. officinalis) dry extract reduces mitochondria-enriched ROS production and improves senescence-related phenotypes in vitro. However, its effects on human skin aging have not been investigated. In this study, we conducted both in vitro and clinical trials using an M. officinalis liquid extract, which can be directly applied to cosmetic formulations. The M. officinalis liquid extract restored mitochondrial function and reduced mitochondria-enriched ROS production. Furthermore, M. officinalis liquid extract activated mitophagy, which removes defective mitochondria, a major source of ROS production. In clinical trials, the M. officinalis liquid extract reduced the mean depth of neck wrinkles by 12.73% and the maximum depth by 17.44%. It also reduced the mean roughness (Ra), root mean square roughness (Rq), and maximum depth of roughness (Rmax) by 12.73%, 10.16%, and 10.81%, respectively. Furthermore, the key to the skin-improving effects of M. officinalis liquid extract lies in its ability to increase skin elasticity by 3.76% and brighten skin tone by 0.76%. In conclusion, this study identified a novel mechanism by which M. officinalis liquid extract rejuvenates skin aging. M. officinalis can be utilized as a cosmetic ingredient to improve skin aging and therapeutic candidate for the development of anti-aging treatments.