Background: Dingchuan tang (asthma-relieving decoction), a formula of nine herbs, has been used for treating respiratory inflammatory diseases for >400 years in the People’s Republic of China. However, the mechanisms underlying the anti-inflammatory action of dingchuan tang is not fully understood. This study aims to investigate the effects of Dingchuan tang essential oil (DCEO) on inflammatory mediators and the underlying mechanism of action. Materials and methods: DCEO was extracted by steam distillation. Lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were used as the cell model. Production of nitric oxide (NO) was determined by the Griess test. Protein secretion and mRNA levels of inflammatory mediators were measured by the enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR), respectively. Protein levels were examined by Western blot. Nuclear localization of nuclear factor-kappa B (NF-κB) was detected using immunofluorescence analyses. Results: DCEO significantly reduced LPS-triggered production of NO and prostaglandin E2 (PGE2) and decreased protein and mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). LPS induced upregulation of protein and mRNA levels of cytokines (interleukin-1β [IL-1β], interleukin-6 [IL-6], tumor necrosis factor-α [TNF-α]), and chemokines (monocyte chemoattractant protein-1 [MCP-1], chemokine [C-C motif] ligand 5 [CCL-5], and macrophage inflammatory protein [MIP]-1α) were suppressed by DCEO treatment. Phosphorylation and nuclear protein levels of transcription factors (activator protein-1 [AP-1], NF-κB, interferon regulatory factor 3 [IRF3]) were decreased by DCEO. Protein levels of phosphorylated IκB-α, IκB kinase α/β (IKKα/β), phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), TGF β-activated kinase 1 (TAK1), TANK-binding kinase 1 (TBK1), extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (p38), and c-Jun N-terminal kinase (JNK) were lowered by DCEO. Moreover, degradation of interleukin-1 receptor-associated kinase 1 (IRAK1) and IRAK4 induced by LPS was inhibited by DCEO treatment. Conclusion: Suppression of the interleukin-1 receptor-associated kinase (IRAK)/NF-κB, IRAK/AP-1 and TBK1/IRF3 pathways was associated with the inhibitory effects of DCEO on inflammatory mediators in LPS-stimulated RAW264.7 macrophages. This study provides a pharmacological justification for the use of dingchuan tang in managing inflammatory disorders.

Cinnamomi ramulus (CR) and Cinnamomi cortex (CC), both sourced from Cinnamomum cassia Presl, are commonly used Chinese medicines in the Chinese Pharmacopeia. However, while CR functions to dissipate cold and to resolve external problems of the body, CC functions to warm the internal organs. To clarify the material basis of these different functions and clinical effects, a simple and reliable UPLC-Orbitrap-Exploris-120-MS/MS method combined with multivariate statistical analyses was established in this study with the aim of exploring the difference in chemical compositions of aqueous extracts of CR and CC. As the results indicated, a total of 58 compounds was identified, including nine flavonoids, 23 phenylpropanoids and phenolic acids, two coumarins, four lignans, four terpenoids, 11 organic acids and five other components. Of these compounds, 26 significant differential compounds were identified statistically including six unique components in CR and four unique components in CC. Additionally, a robust HPLC method combined with hierarchical clustering analysis (HCA) was developed to simultaneously determine the concentrations and differentiating capacities of five major active ingredients in CR and CC: coumarin, cinnamyl alcohol, cinnamic acid, 2-methoxycinnamic acid and cinnamaldehyde. The HCA results showed that these five components could be used as markers for successfully distinguishing CR and CC. Finally, molecular docking analyses were conducted to obtain the affinities between each of the abovementioned 26 differential components, focusing on targets involved in diabetes peripheral neuropathy (DPN). The results indicated that the special and high-concentration components in CR showed high docking scores of affinities with targets such as HbA1c and proteins in the AMPK–PGC1–SIRT3 signaling pathway, suggesting that CR has greater potential than CC for treating DPN.

Herba Siegesbeckiae (HS, Xixiancao in Chinese) is a commonly used traditional Chinese medicinal herb for soothing joints. In ancient materia medica books, HS is recorded to be the aerial part of Siegesbeckia pubescens Makino (SP) which is also the only origin of HS in the 1963 edition of the Chinese Pharmacopeia (ChP). The aerial parts of Siegesbeckia orientalis L. (SO) and Siegesbeckia glabrescens Makino (SG) have been included as two additional origins for HS in each edition of ChP since 1977. However, chemical and pharmacological comparisons among these three species have not been conducted. An HPLC with diode array detector (HPLC-DAD) method combined with similarity analysis, hierarchical cluster analysis (HCA) and principal component analysis (PCA) was developed for comparing the fingerprint chromatograms of the three species. The inhibitory effects of the three species on NO production and IL-6 secretion in LPS-stimulated RAW264.7 macrophages were compared. Fingerprint chromatograms of the three species showed different profiles, but had 13 common peaks. Results from HCA and PCA of the common peaks demonstrated that all 14 herbal samples of the three species tended to be grouped and separated species dependently. The extents of inhibition on NO production and IL-6 secretion of the three species were different, with SG being the most and SP the least potent. Both chemical profiles and inflammatory mediator-inhibitory effects of the three species were different. These findings provide a chemical and pharmacological basis for determining whether the three species can all serve as the origins of HS.

Paederia scandens (Lour.) Merr. (P. scandens), as an edible and medicinal herb, is commonly used for treating gastric ulcer in China; however, its mechanistic and effective substances studies remain limited. This study aimed to investigate the antigastric ulcer effects of aqueous extracts of P. scandens (PS-AE) and explore the involvement of NF-κB signaling in this effect. In addition, the study aimed to identify the effective substances by exploring NF-κB inhibitors. The main components of PS-AE were identified using an UPLC-MS method. HCl/EtOH-induced acute gastric ulcer in rats, and LPS-stimulated RAW264.7 cells were used to determine the antigastric ulcer effects of PS-AE in vivo and in vitro, respectively. Histopathological changes of the ulcer tissues were observed using staining methods of HE and PAS; secretions of inflammatory cytokines and oxidative stress indexes were measured using biochemical test kits; protein levels of NF-κB signaling pathway-related molecules were measured using Western Blot. NF-κB inhibitors identification in P. scandens was performed by developing HipHop pharmacophore model, and the results were further validated by molecular docking. In vivo, PS-AE significantly attenuated gastric ulcer in rats; reduced inflammation by adjusting the inflammatory cytokines TNF-α, IL-1β, and IL-6 levels; and induced oxidative stress can be alleviated via adjusting the levels of SOD, MDA, and GSH-Px. In addition, PS-AE may play an anti-inflammatory role mainly through NF-κB signaling pathway. Following pharmacophore modeling and molecular docking, 13 potential inhibitors targeting NF-κB were identified. In addition, in vitro, PS-AE and paederoside could significantly inhibit the activation of NF-κB p65 and the productions of downstream cytokines including NO, TNF-α, and IL-6. PS-AE protective effects on gastric ulcer damage induced by HCl/EtOH in rats, which is probably associated with its antioxidant effect and the inhibitory effects on levels of inflammatory mediators regulated by NF-κB signaling pathway. 13 potential NF-κB-targeting inhibitors are probably effective substances contributing to the herbs pharmacological effect. In practical application, Paederia scandens, a traditional food and medicinal plant, possessed diversified chemical components and multiple pharmacological activities (anti-inflammatory, bacteriostasis, and antioxidative.). In China, P. scandens has been used as a traditional medicine to treat gastritis for hundreds of years, and it may be a potentially effective dietary product to improve gastric ulcer. This study shows that P. scandens exerts protective effects on gastric ulcer damage induced by HCl/EtOH in rats, which is probably associated with its antioxidant effect and the inhibitory effects on levels of inflammatory mediators regulated by NF-κB signaling pathway, which provides pharmacological justifications for the functional food use of P. scandens for treating gastric disease.