Isorhapontigenin attenuates allergic asthma by reducing airway inflammation and oxidative stress.

Abstract

Gnetum cleistostachyum has been used in traditional Chinese medicine to treat arthritis and bronchitis. Isorhapontigenin, a naturally occurring stilbenoid structurally related to resveratrol, is isolated from G. cleistostachyum and has been reported to exhibit anti-inflammatory and antioxidant properties. Here, we examined whether isorhapontigenin can ameliorate airway inflammation, oxidative stress, and airway hyperresponsiveness (AHR) in an ovalbumin (OVA)-induced mouse model of allergic asthma. Female BALB/c mice were sensitized and challenged with OVA and subsequently administered isorhapontigenin. Lung function and AHR were evaluated, along with histopathological alterations. Inflammatory profiles and oxidative stress-associated indices were determined using bronchoalveolar lavage fluid (BALF) and lung tissues. Complementary in vitro studies were conducted in human bronchial epithelial BEAS-2B cells to assess cytokine-related responses, intracellular reactive oxygen species (ROS) generation, and monocyte-epithelial adhesion. Isorhapontigenin treatment markedly improved AHR and mitigated airway pathology in asthmatic mice, including inflammatory cell influx, mucus-producing goblet cell expansion, and airway remodeling features such as collagen accumulation. Consistently, BALF analysis showed reduced Th2-associated cytokines, eotaxins, and other pro-inflammatory mediators. Isorhapontigenin also alleviated oxidative stress-related disturbances and was associated with improved inflammatory status in lung tissues. In BEAS-2B cells, isorhapontigenin suppressed the expression of eotaxins, intercellular adhesion molecule-1, and pro-inflammatory cytokines, accompanied by decreased ROS production and reduced monocyte adhesion. These data indicate that isorhapontigenin attenuates key asthma phenotypes by concurrently dampening inflammatory responses and oxidative stress. Isorhapontigenin may therefore represent a promising candidate for the development of adjunctive strategies for asthma management.