Shaoying Gong,Jiachen Zheng,Junjie Zhang,Yucong Wang,Zhixin Xie,Yubao Wang,Jianchun Han
Intestinal epithelial barrier dysfunction can cause several intestinal diseases. Flavonoids have been shown to be beneficial to the intestinal epithelial barrier function. However, the effects of taxifolin (TAX), a naturally occurring flavonoid, on the intestinal epithelial barrier function are unclear. Thus, the aims of this study were to investigate the protective effect and potential mechanism of TAX against lipopolysaccharide (LPS)-induced intestinal epithelial barrier dysfunction in a Caco-2 cell monolayer model. Our results showed that TAX increased the transepithelial electrical resistance (TEER) and decreased the fluorescein isothiocyanate (FITC)-dextran (4 kDa) flux in the damaged intestinal epithelial barrier. Meanwhile, TAX inhibited an LPS-induced decrease in mRNA and protein expression of tight junction (TJ) proteins (claudin-1, zonula occludens [ZO]-1, and occludin), and ameliorating the continuous distribution pattern disrupted of TJs. These results suggested that TAX ameliorated intestinal epithelial barrier dysfunction. Regarding the underlying mechanism, TAX reduced the LPS-induced secretion of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in Caco-2 cell monolayers. In addition, TAX suppressed the phosphorylation of nuclear factor kappa-B (NF-κB), inhibitor protein of NF-κBα (IκBα), and myosin light chain (MLC), and downregulated the expression of myosin light chain kinase (MLCK) in LPS-treated Caco-2 cells. In summary, TAX can maintain TJ proteins by inhibiting the NF-κB/MLCK pathway and pro-inflammatory factor secretion to ameliorate LPS-induced intestinal epithelial barrier dysfunction. Thus, TAX is a promising candidate agent for use in functional food to ameliorate intestinal barrier dysfunction.
Ye Wang,Shao-jie Chen,Ting Ma,Qiu Long,Lan Chen,Ke-xin Xu,Yu Cao
Melanoma is a skin cancer originating from melanocytes. The global incidence rate of melanoma is rapidly increasing, posing significant public health challenges. Identifying effective therapeutic agents is crucial in addressing this growing problem. Natural products have demonstrated promising anti-tumor activity. In this study, a plant flavonoid, taxifolin, was screened using Weighted Correlation Network Analysis (WGCNA) in combination with the Connectivity Map (CMAP) platform. Taxifolin was confirmed to inhibit the proliferation, migration, and invasion ability of melanoma A375 and MV-3 cells by promoting apoptosis. Additionally, it suppressed the Epithelial-Mesenchymal Transition (EMT) process of melanoma cells. Cyber pharmacological analysis revealed that taxifolin exerts its inhibitory effect on melanoma through the PI3K/AKT signaling pathway, specifically by downregulating the protein expression of p-PI3K and p-AKT. Notably, the addition of SC-79, an activator of the PI3K/AKT signaling pathway, reversed the effects of taxifolin on cell migration and apoptosis. Furthermore, in vivo experiments demonstrated that taxifolin treatment slowed tumor growth in mice without significant toxic effects. Based on these findings, taxifolin holds promise as a potential drug for melanoma treatment.