Prunus yedoensis bark extract containing naringenin enhances hyaluronic acid synthesis and epidermal barrier function via MAPK/CREB and Akt/NF-κB pathways

Hyaluronic acid (HA) is an intrinsic glycosaminoglycan within the dermal matrix, essential for maintaining skin hydration and elasticity. Filaggrin, a crucial protein, plays a significant role in the formation of the skin barrier and the retention of moisture. Therefore, strategies aimed at augmenting HA synthesis and fortifying the epidermal barrier are vital for preserving skin health. This study investigates the efficacy of Prunus yedoensis bark ethanol extract (PYBEE) and its principal bioactive compound, naringenin, both recognized for their potent antioxidant and anti-inflammatory properties, in promoting HA synthesis and enhancing epidermal barrier function. In cultured HaCaT keratinocytes, administration of non-cytotoxic concentrations of PYBEE and naringenin resulted in a significant upregulation of HA expression and an increase in hyaluronic acid synthase-2 (HAS2) levels. Mechanistic studies revealed that both PYBEE and naringenin activate the mitogen-activated protein kinase (MAPK) signaling pathway, leading to the phosphorylation of cyclic AMP response element-binding protein (CREB), a pivotal transcription factor governing HAS2 expression. Additionally, these agents stimulated the Akt pathway, facilitating the nuclear translocation of nuclear factor kappa B (NF-κB) and enhancing HAS2 transcription, thereby elevating HA production within the extracellular matrix. Moreover, treatment with PYBEE significantly increased filaggrin expression in HaCaT cells and improved transepithelial electrical resistance (TEER), indicative of strengthened epidermal barrier integrity. These findings suggest that PYBEE, with naringenin as a key active component, holds substantial potential in promoting HA synthesis and reinforcing the epidermal barrier. Consequently, PYBEE may serve as a functional ingredient in dermatological formulations aimed at enhancing skin hydration and barrier function, supporting its prospective application in therapeutic skincare interventions.