Our study aimed to investigate whether unripe pear extract (UP) could provide protection against UVB-induced damage to both mouse skin and keratinocytes. We observed that UVB exposure, a common contributor to skin photoaging, led to wrinkle formation, skin dryness, and inflammation in mice. Nevertheless, these effects were mitigated in the groups of UVB-irradiated mice treated with UP. Moreover, UP treatment at 400 μg/mL increased the antioxidant enzyme activities (sodium dodecyl sulfate, 2.22-fold higher; catalase, 2.91-fold higher; GPx, 1.96-fold higher) along with sphingomyelin (1.58-fold higher) and hyaluronic acid (1.31-fold higher) levels in UVB-irradiated keratinocytes. In the keratinocytes irradiated with UVB, UP 400 μg/mL resulted in reduced cytokine production (TNF-α, 33.2%; IL-1β, 45.3%; IL-6, 33.4%) and the expression of inflammatory pathway-related proteins. The findings indicate that UP has a direct protective effect on UVB-irradiated keratinocytes and is also able to shield against photoaging induced by UVB. Hence, it is suggested that UP could contribute to improved skin health by averting skin photoaging.
Keywords: UVB; keratinocytes; photoaging; unripe pear.