Objectives: Atopic dermatitis (AD) is a long-term, recurring inflammatory skin condition characterized by impaired epidermal barrier function and abnormal immune system regulation. Pine pollen has traditionally been used for dermatological treatments, though its active components remain unclear. The primary objective of this study was to pinpoint the active constituents of pine pollen and elucidate its therapeutic effects against AD. Methods: The safety concentration ranges and protective efficacy of nine pine pollen constituents against 2,4-dinitrochlorobenzene (DNCB)-induced HaCaT cell damage were evaluated using the CCK-8 assay. Furthermore, models of DNCB-induced damage were established both in vitro (HaCaT cells) and in vivo (BALB/c mice) to explore the protective effects of the key functional component. Results: Our findings identified pine pollen polysaccharides (PPPS) as the principal bioactive constituent, characterized by a unique infrared absorption spectral profile and a sponge-like architecture with three-dimensional interconnected porous networks. In vitro, PPPS inhibited DNCB-induced decreases in cell viability, morphological abnormalities, oxidative stress, and apoptosis. In vivo, PPPS alleviated DNCB-induced skin lesions by attenuating epidermal hyperplasia, suppressing mast cell infiltration, inhibiting cell apoptosis, and downregulating the expression of IL-4 and IL-17A. Conclusions: This study provides evidence that PPPS from pine pollen can alleviate epidermal damage in AD, offering a novel therapeutic strategy for AD treatment.

To investigate the therapeutic impact of Forsythia suspensa extract (FS) on RSV-infected mice and explore its antiviral pharmacodynamic foundations. Methods: An integrated analytical approach, combining UPLC-Q-TOF/MS with network pharmacology, was employed to analyze and identify the chemical constituents in FS, particularly those exhibiting antiviral properties against RSV. The study integrated network pharmacology and metabolomics for further analysis, and molecular docking and interaction experiments were conducted to validate the pharmacodynamic mechanisms. Finally, an RSV pneumonia mouse model was employed to evaluate the therapeutic influence of FS, including pathological and immunohistochemistry assessments. Twenty-five components in FS were identified through UPLC-Q-TOF/MS analysis. Integrated network pharmacology data revealed 43 effective components and predicted 113 potential targets of FS for anti-RSV activity. Metabolomics analysis identified 14 metabolite biomarkers closely linked to RSV-induced metabolic disruptions involving pathways. Moreover, molecular docking and Biacore experiments provided additional confirmation that FS primarily exerts its effects through compounds such as rutin, quercetin, and kaempferol. Immunohistochemistry experiments demonstrated a significant reduction in the expression of relevant proteins following FS administration, affirming its capacity to ameliorate lung inflammation induced by RSV infection through the modulation of Toll-like receptor signaling pathways. The data presented in this study illustrate that FS exerts its anti-RSV effects by regulating the Toll-like receptor signaling pathway and the arachidonic acid metabolism pathway via rutin, quercetin, and kaempferol. Furthermore, the approach of combining network pharmacology with metabolomics proves to be an effective research strategy for investigating the bioactive constituents of medicinal plants and elucidating their pharmacological effects.

Atopic dermatitis (AD) is a chronic inflammatory skin disorder characterized by complex cellular heterogeneity. While several studies have begun to characterize the single-cell transcriptomic landscape of human AD, comparable high-resolution data from widely used mouse models remain lacking. Here, we employed single-cell RNA sequencing to profile skin from a 2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model, which recapitulates key pathological features of human AD and is frequently used for mechanistic and therapeutic investigations. In this study, we identified 21 transcriptionally distinct clusters encompassing 11 major cell types. DNCB exposure resulted in robust immune infiltration, including Th2/Th17-skewed T cells, monocytes, macrophages, and inflamed endothelial cells. Keratinocytes were depleted and exhibited hyperproliferation, apoptosis, and differentiation defects, while novel fibroblast subsets displayed impaired maturation and pro-inflammatory states. Intercellular communication analysis revealed monocytes as dominant ligand-receptor signaling hubs. This study provides the first comprehensive single-cell atlas of the DNCB-induced AD model, revealing immune dysregulation, epithelial remodeling, and stromal reprogramming. Notably, the transcriptomic parallels with human AD validate the model’s translational relevance. Our findings establish a foundational reference for future AD research using the DNCB mouse model and offer valuable insights for interpreting drug and target discovery studies performed in this context.