Abstract
The skin is an important organ in the human body that protects the body from environmentally hazardous substances. Reactive oxygen species (ROS) cause inflammatory reactions and degradation of the extracellular matrix leading to skin aging and various cutaneous lesions. This study evaluated the potential of isoflavones isolated from Maclura tricuspidata fruit to prevent TNF-α-induced skin inflammation in normal human dermal fibroblasts (HDFs). It focused on alpinumisoflavone (AIF) that suppressed the accumulation of ROS and nitric oxide (NO) in tumor necrosis factor-alpha (TNF-α)-treated HDFs. AIF inhibited the TNF-α-induced increase in matrix metalloproteinase-1, decreased procollagen I α1, and suppressed pro-inflammatory mediators and pro-inflammatory cytokines, including NO synthase, cyclooxygenase-2, interleukin (IL)-1β, IL-6, and IL-8 that trigger inflammatory responses. AIF inhibited nuclear factor-κB and activating protein 1 mitogen-activated protein kinases that were increased by TNF-α stimulation. These results suggest that AIF may protect skin from aging and various cutaneous lesions.