Black Ginseng Extract Exerts Potentially Anti-Asthmatic Activity by Inhibiting the Protein Kinase Cθ-Mediated IL-4/STAT6 Signaling Pathway.

Asthma is a chronic inflammatory lung disease that causes respiratory difficulties. Black ginseng extract (BGE) has preventative effects on respiratory inflammatory diseases such as asthma. However, the pharmacological mechanisms behind the anti-asthmatic activity of BGE remain unknown. To investigate the anti-asthmatic mechanism of BGE, phorbol 12-myristate 13-acetate plus ionomycin (PMA/Iono)-stimulated mouse EL4 cells and ovalbumin (OVA)-induced mice with allergic airway inflammation were used. Immune cells (eosinophils/macrophages), interleukin (IL)-4, -5, -13, and serum immunoglobulin E (IgE) levels were measured using an enzyme-linked immunosorbent assay. Inflammatory cell recruitment and mucus secretion in the lung tissue were estimated. Protein expression was analyzed via Western blotting, including that of inducible nitric oxide synthase (iNOS) and the activation of protein kinase C theta (PKCθ) and its downstream signaling molecules. BGE decreased T helper (Th)2 cytokines, serum IgE, mucus secretion, and iNOS expression in mice with allergic airway inflammation, thereby providing a protective effect. Moreover, BGE and its major ginsenosides inhibited the production of Th2 cytokines in PMA/Iono-stimulated EL4 cells. In EL4 cells, these outcomes were accompanied by the inactivation of PKCθ and its downstream transcription factors, such as nuclear factor of activated T cells (NFAT), nuclear factor kappa B (NF-κB), activator of transcription 6 (STAT6), and GATA binding protein 3 (GATA3), which are involved in allergic airway inflammation. BGE also inhibited the activation of PKCθ and the abovementioned transcriptional factors in the lung tissue of mice with allergic airway inflammation. These results highlight the potential of BGE as a useful therapeutic and preventative agent for allergic airway inflammatory diseases such as allergic asthma.

Daphnodorin C isolated from the stems of Daphne kiusiana Miquel attenuates airway inflammation in a mouse model of chronic obstructive pulmonary disease.

BACKGROUND: Since long-term or high-dose use of COPD medication causes adverse effects in patients with COPD, more effective and safer ways to manage COPD symptoms are required. Daphne kiusiana Miquel is a medicinal plant, but its anti-COPD efficacy was little studied. PURPOSE: We investigated the anti-COPD activity and molecular mechanism of action of active compounds isolated from D. kiusiana to find drug candidates for COPD. METHODS: We isolated seven compounds (1-7) in an ethyl acetate (EtOAc) fraction from D. kiusiana, and determined that seven compounds effectively control the inflammatory responsiveness in both PMA-stimulated lung epithelial cells (in vitro) and/or in COPD model mice using cigarette smoke- and lipopolysaccharides-exposed animals in vivo. RESULTS: We show that the ethyl acetate (EtOAc) fraction from D. kiusiana. suppresses inflammatory response in both PMA-stimulated human lung epithelial cells (in vitro) and COPD model mice (in vivo). The EtOAc fraction effectively suppresses various inflammatory responses, such as mucus secretion, ROS production, bronchial recruitment of inflammatory cells, and release of proinflammatory cytokines. Additionally, we isolated three compounds with anti-inflammatory efficacy from the EtOAc fraction, out of which daphnodorin C was the most effective. Finally, we demonstrated that daphnodorin C negatively regulates inflammatory gene expression by suppressing NF-κB and specific MAPK signaling pathways (JNK and p38) in vitro and in vivo. CONCLUSIONS: These results suggest that daphnodorin C could be a promising therapeutic alternative for managing COPD symptoms.

Piscroside C inhibits TNF-α/NF-κB pathway by the suppression of PKCδ activity for TNF-RSC formation in human airway epithelial cells.

BACKGROUND: Piscroside C, isolated from Pseudolysimachion rotundum var. subintegrum, is a novel iridoid glycoside with therapeutic efficacy in a mouse model of chronic obstructive pulmonary disease (COPD). Piscroside C has been reported as a constituent of YPL-001 (under Phase 2a study, ClinicalTrials.gov identifier NCT02272634). PURPOSE: To investigate the mechanisms behind piscroside C therapeutic effects on COPD in human airway epithelial NCI-H292 cells. METHODS: We tested if piscroside C effectively suppresses MUC5AC gene expression and TNF-RSC/IKK/NF-κB cascades in TNF-α-stimulated NCI-H292 cells by employing, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, luciferase reporter assays, chromatin immunoprecipitation assays and immunoprecipitation. RESULTS: Piscroside C markedly suppressed the expression of TNF-α-induced MUC5AC mucus protein by inhibiting the transcriptional activity of NF-κB in NCI-H292 cells. Indeed, piscroside C negatively regulated the function of TNF receptor 1 signaling complex (TNF-RSC, an upstream regulator of the NF-κB pathway) without affecting its extracellular interaction with the TNF-α ligand. This inhibitory effect by piscroside C is mediated by the inactivation of protein kinase C (PKC), an essential regulator of TNF-RSC. PKC inactivation by piscroside C results in decreased PKCδ binding to a TRAF2 subunit of TNF-RSC and subsequent reduced IKK phosphorylation, resulting in NF-κB inactivation. CONCLUSION: We propose that piscroside C is a promising therapeutic constituent of YPL-001 through its inhibition of PKCδ activity in the TNF-RSC/IKK/NF-κB/MUC5AC signaling cascade.

In vitro maintenance of Clonorchis sinensis adult worms.

Clonorchis sinensis is a biological carcinogen inducing human cholangiocarcinoma, and clonorchiasis is one of the important endemic infectious diseases in East Asia. The present study investigated survival longevity of C. sinensis adult worms in various in vitro conditions to find the best way of keeping the worms longer. The worms were maintained in 0.85% NaCl, 1×PBS, 1×Locke's solution, RPMI-1640, DMEM, and IMDM media, and in 1×Locke's solution with different supplements. All of the worms died within 3 and 7 days in 0.85% NaCl and 1×PBS, respectively, but survived up to 57 days in 1×Locke's solution. The worms lived for 106 days in DMEM, and 114 days in both RPMI-1640 and IMDM media. The survival rate in RPMI-1640 medium was the highest (50%) compared to that in DMEM (20±10%) and in IMDM (33.3±25.2%) after 3 months. The 1×Locke's solution with 0.005% bovine bile supplement showed increased duration of maximum survival from 42 days to 70 days. Higher concentration of bile supplements than 0.005% or addition of glucose were disadvantageous for the worm survival. The worms died rapidly in solutions containing L-aspartic acid, L-glutamic acid, and adenine compared to L-arginine, L-serine, and L-tryptophan. In conclusion, the 1×Locke's solution best supports the worms alive among inorganic solutions for 57 days, and the RPMI-1640 medium maintains living C. sinensis adults better and longer up to 114 days in vitro than other media.