Cinnamophilin Isolated from Cinnamomum philippinense Protects against Collagen Degradation in Human Chondrocytes

To investigate the therapeutic potential of naturally occurring cinnamophilin against cartilage degradation and its action mechanisms, its effects on matrix metalloproteinase (MMP)‐1 and ?13 induction were examined in the human SW1353 chondrocytic cell line. Human chondrocytes (SW1353) were stimulated with interleukin (IL)‐1β, and then mitogen‐activated protein kinase (MAPK) and c‐Jun activations, inhibitory κB‐α (IκB‐α) degradation, and MMP‐1, and 13 expressions were assayed by a Western blot analysis. Cinnamophilin strongly inhibited MMP‐1 and ?13 induction in IL‐1β‐treated (30 ng/mL) SW1353 cells in a concentration‐dependent manner, and it also reduced MAPK family members including extracellular signal‐regulated kinase (ERK), p38 MAPKs, and c‐Jun N‐terminal kinase. Moreover, nuclear factor (NF)‐κB signaling activation through IκB‐α degradation, IκB kinase (IKK)‐α/β, and p‐65 phosphorylation was restored by cinnamophilin upon IL‐1β stimulation. Importantly, results showed that IL‐1β‐induced activation of phosphorylated (p)‐c‐Jun in chondrocytes was significantly inhibited by cinnamophilin. These results indicate that cinnamophilin inhibited MMP‐1 and ?13 expressions in IL‐1β‐treated chondrocytes through either NF‐κB or ERK/p38 MAPK downregulation and/or suppressing p‐c‐Jun pathways. Furthermore, these findings suggest that cinnamophilin may have the potential for chondroprotection against collagen matrix breakdown in cartilage of diseased tissues such as those found in arthritic disorders. Copyright © 2012 John Wiley & Sons, Ltd.     

Antiallergic effect of KOB03, a polyherbal medicine, on mast cell-mediated allergic responses in ovalbumin-induced allergic rhinitis mouse and human mast cells

Ethnopharmacological relevance

KOB03 is a polyherbal medicine consisting of five different herbs and has commonly been used for the treatment of various allergic diseases. However, its precise anti-allergic effect and mechanism remain unknown.

Aim of the study

The aim of this study was to investigate the effect of KOB03 on allergic responses through the regulation of mast-cell mediated allergic inflammation.

Materials and methods

To determine the effect of KOB03 on mast cell-mediated allergic reactions, we investigated the parameter changes of in vivo models such as compound 48/80-induced systemic anaphylaxis and ovalbumin (OVA)-induced allergic rhinitis, and the release of allergic inflammatory mediators such as histamine, immunoglobulin (Ig) E, and inflammatory cytokines via the MAPKs and NF-kappaB pathways.

Results

The oral administration of KOB03 at doses of 100 and 200 mg/kg inhibited histamine release and mortality in compound 48/80-induced anaphylactic rats. KOB03 also improved rhinitis symptoms, inhibited the histopathological changes of nasal mucosa, and decreased the serum levels of histamine, OVA-specific IgE and TNF-α in OVA-induced allergic rhinitis in mice. In vitro, KOB03 suppressed compound 48/80-induced histamine release by blocking mast cell degranulation. In addition, KOB03 inhibited the production of inflammatory cytokines such as TNF-α, IL-1β, IL-6 and IL-8 in PMA/A23187-stimulated HMC-1 mast cells by suppressing their gene expression and blocking the ERK1/2 and p38 MAPK and NF-κB pathways.

Conclusions

These results suggest that KOB03 has an anti-allergic effect by modulating mast cell-mediated allergic responses in allergic rhinitis.     

Hyperoside Regulates the Level of Thymic Stromal Lymphopoietin through Intracellular Calcium Signalling

Hyperoside (HYP) is the principle active component of Crataegus pinnatifida. Thymic stromal lymphopoietin (TSLP) plays a vital role in the pathogenesis of allergic reactions. Here, we investigated how HYP regulates the levels of TSLP in a human mast cell line, HMC‐1 cells. We analyzed the levels of TSLP by treatment with HYP in phorbol myristate acetate plus calcium ionophore A23187‐stimulated HMC‐1 cells with ELISA and a polymerase chain reaction analysis. We also analyzed the pathway that HYP regulates TSLP by measuring the level of fluorescent intracellular calcium and using a Western blot analysis. HYP decreased the level of intracellular calcium in stimulated HMC‐1 cells. It also significantly decreased the production and mRNA expression of TSLP in stimulated HMC‐1 cells. It significantly decreased the levels of receptor‐interacting protein 2 and active caspase‐1 in stimulated HMC‐1 cells. HYP significantly decreased the translocation of NF‐κB into the nucleus and degradation of IκBα in the cytoplasm in stimulated HMC‐1 cells. Furthermore, it significantly decreased the production and mRNA expression of interleukin‐1β and interleukin‐6 in stimulated HMC‐1 cells. Taken together, our findings establish HYP as a potential agent for the treatment of allergic reactions. Copyright © 2013 John Wiley & Sons, Ltd.     

Rhynchophylline Attenuates LPS‐induced Pro‐inflammatory Responses through Down‐regulation of MAPK/NF‐κB Signaling Pathways in Primary Microglia

Excessive activation of microglial cells has been implicated in various types of neuroinflammation. Suppression of microglial activation would have therapeutic benefits, leading to the alleviation of the progression of neurodegeneration. In this study, the inhibitory effects of rhynchophylline (RIN), a tetracyclic oxindole alkaloid component isolated from Uncaria rhynchophylla (Miq.) Jacks., on the production of pro‐inflammatory mediators were investigated in lipopolysaccharide (LPS)‐stimulated microglia. The results showed that RIN markedly reduced the production of nitric oxide (NO), prostaglandins E₂ (PGE₂), monocyte chemoattractant protein (MCP‐1), tumor necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β) in LPS‐activated microglia. The mRNA expression levels of iNOS and COX‐2 were also depressed by RIN in a concentration‐dependent manner. Further studies revealed that RIN blocked IκBα phosphorylation and degradation, inhibited the phosphorylation of mitogen‐activated protein kinases (MAPKs). In summary, these data suggest that RIN suppresses inflammatory responses of microglia and may act as a potential therapeutic agent for various neurodegenerative diseases involving neuroinflammation. Copyright © 2012 John Wiley & Sons, Ltd.     

Cheongyeolsaseuptang inhibits production of TNF-alpha, IL-6 and IL-8 as well as NF-kappa B activation in human mast cells

Traditional Korean medicine, Cheongyeolsaseuptang (CYSST) has been widely applied as a treatment of rheumatoid arthritis (RA) in Korea. However, its effect in experimental models remains unknown. Recent reports suggest that in patients with RA, synovial mast cells increase in number and show signs of activation and production of cytokines. In this study, we investigated the effect of CYSST on production of cytokines by activated human mast cell line, HMC-1. When CYSST (1mg/ml) was added, the production of tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8 was significantly inhibited about 37, 33.6, and 48%, respectively on phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated HMC-1 cells. In addition, CYSST inhibited PMA plus A23187-induced activation of nuclear factor-kappaB. These findings may help understanding the mechanism of action of this medicine leading to control activated mast cells on inflammatory condition like RA.     

The anti‐anaphylactoid effects of Piperine through regulating MAS‐related G protein‐coupled receptor X2 activation

Mast cells play an important role in inflammatory and allergic diseases. MAS‐related G protein‐coupled receptor X2 (MRGPRX2) is a novel G protein‐coupled receptor in mast cells that mediates drug‐induced anaphylactoid reactions. Piperine has been reported to have anti‐inflammatory and anti‐allergic pharmacological activities. However, whether the pharmacological effects are regulated by MRGPRX2 has not yet been reported. The purpose of this study was to assess the anti‐anaphylactoid effect of Piperine and to explore its potential mechanism. The anti‐anaphylactoid effect of Piperine was assessed by an in vivo mouse hindpaw extravasation model. Mast cell intracellular calcium mobilization was measured by a calcium imaging assay. An enzyme immunoassay was used to evaluate the release of pro‐inflammatory factors from stimulated mast cells. Activated mast cell related signals were assessed by western blot. A cell membrane chromatography assay was used to determine the binding characteristics of Piperine and MRGPRX2. The results showed that Piperine suppressed mast cell intracellular Ca²⁺ mobilization, inhibited cytokines and chemokines release, and down‐regulated the phosphorylation level of phospholipase Cγ1, protein kinase C, inositol 1,4,5‐triphate receptor, P38, protein kinase B, and ERK. Meanwhile, Piperine can bind to MRGPRX2 as a specific antagonist. Hence, Piperine can be served as a novel therapeutic drug candidate for MRGPRX2‐mediated anaphylactoid reactions.     

Blockade of IL-6 secretion pathway by the sesquiterpenoid atractylenolide III

Atractylenolide III (1) is the major bioactive component of Atractylodes lancea. The aim of this study was to analyze the effect on the regulation of interleukin (IL)-6 secretion pathway caused by 1. This sesquiterpenoid inhibited the secretion and expression of IL-6 in phorbol 12-myristate 13-acetate- and calcium ionophore A23187-stimulated human mast cells (HMC)-1. In addition, 1 inhibited histamine release in stimulated HMC-1 cells. In stimulated HMC-1 cells, 1 suppressed activation of p38 mitogen-activated protein kinase, C-Jun-N-terminal protein kinase, and nuclear factor-κB. In addition, 1 suppressed the activation of caspase-1 and the expression of receptor interacting protein-2. These results provide new insights that atractylenolide III (1) may control immunological reactions by regulating the cellular functions of IL-6 in mast cells.     

Phlomis umbrosa root inhibits mast cell-dependent allergic reactions and inflammatory cytokine secretion

The effect of an aqueous extract of Phlomis umbrosa Turcz. (Labiatae) root (PUAE) on mast cell-dependent allergic reactions and inflammatory cytokine secretion were investigated. PUAE (0.01-1 g/kg) inhibited compound 48/80-induced systemic allergic reaction. When PUAE was employed in a systemic allergic reaction test, the plasma histamine levels were reduced in a dose-dependent manner. PUAE (0.1 and 1 g/kg) also significantly inhibited the local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. PUAE (0.001-1 mg/mL) dose-dependently inhibited the histamine release from rat peritoneal mast cells activated by compound 48/80 or anti-DNP IgE. PUAE (0.01-1 mg/mL) inhibited the secretion of interleukin (IL)-1beta in phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated human mast cell line (HMC-1) cells. PUAE (1 mg/mL) inhibited the gene expression and production of the main inflammatory cytokine, TNF-alpha, in HMC-1 cells. These results provide evidence that PUAE may be beneficial in the treatment of allergic diseases.     

Nimbolide Inhibits Nuclear Factor‐КB Pathway in Intestinal Epithelial Cells and Macrophages and Alleviates Experimental Colitis in Mice

Nimbolide is a limonoid extracted from neem tree (Azadirachta indica) that has antiinflammatory properties. The effect of nimbolide on the nuclear factor‐kappa B (NF‐κB) pathway in intestinal epithelial cells (IECs), macrophages and in murine colitis models was investigated. The IEC COLO 205, the murine macrophage cell line RAW 264.7, and peritoneal macrophages from interleukin‐10‐deficient (IL‐10^?/?) mice were preconditioned with nimbolide and then stimulated with tumor necrosis factor‐α (TNF‐α) or lipopolysaccharide. Dextran sulfate sodium‐induced acute colitis model and chronic colitis model in IL‐10^?/? mice were used for in vivo experiments. Nimbolide significantly suppressed the expression of inflammatory cytokines (IL‐6, IL‐8, IL‐12, and TNF‐α) and inhibited the phosphorylation of IκBα and the DNA‐binding affinity of NF‐κB in IECs and macrophages. Nimbolide ameliorated weight loss, colon shortening, disease activity index score, and histologic scores in dextran sulfate sodium colitis. It also improved histopathologic scores in the chronic colitis of IL‐10^?/? mice. Staining for phosphorylated IκBα was significantly decreased in the colon tissue after treatment with nimbolide in both models. Nimbolide inhibits NF‐κB signaling in IECs and macrophages and ameliorates experimental colitis in mice. These results suggest nimbolide could be a potentially new treatment for inflammatory bowel disease. Copyright © 2016 John Wiley & Sons, Ltd.     

Transgenic Panax ginseng inhibits the production of TNF-alpha, IL-6, and IL-8 as well as COX-2 expression in human mast cells

The most well-known medicinal plant, Panax ginseng (P. ginseng), contains various phytosterols and bioactive triterpene saponins (ginsenosides). Squalene synthase is a key regulatory enzyme for triterpene biosynthesis and overexpression of the squalene synthase confers the hyper-production of triterpene saponins to form transgenic ginseng. In this study, we have investigated whether and how transgenic P. ginseng modulates an inflammatory reaction in a stimulated human mast cell line, HMC-1. It was found that transgenic P. ginseng inhibited the production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, and the expression of cyclooxygenase-2 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (PMACI)-stimulated HMC-1. Additionally, we have shown that transgenic P. ginseng suppressed the intracellular calcium level induced by PMACI. These results provide new insights into the pharmacological actions of transgenic P. ginseng as a potential molecule for use in therapy in mast cell-mediated inflammatory diseases.     

Ramalin Isolated from Ramalina Terebrata Attenuates Atopic Dermatitis‐like Skin Lesions in Balb/c Mice and Cutaneous Immune Responses in Keratinocytes and Mast Cells

Atopic dermatitis (AD) is a chronic inflammatory skin disease that involves eczematous skin lesions with pruritic erythematous papules. In this study, we investigated the mitigating effects of ramalin, a component of the Antarctic lichen Ramalina terebrata against AD in vivo and in vitro. Oral administration of ramalin lessened scratching behaviors and significantly reduced both serum immunoglobulin E and IL‐4 levels, and mRNA levels of IL‐4 and IL‐10 in AD‐induced Balb/c mice. In vitro, treatment with ramalin produced significantly less inflammatory chemokines and cytokines, including TARC, MCP‐1, RANTES, and IL‐8 in TNF‐α‐stimulated HaCaT cells. In addition, ramalin inhibited the activation of nuclear factor‐kappa B as well as the phosphorylation of mitogen‐activated protein kinases (MAPK). Furthermore, ramalin treatment resulted in decreased production of β‐hexosaminidase and proinflammatory cytokines IL‐4, IL‐6, and TNF‐α in 2,4 dinitrophenyl‐human serum albumin‐stimulated RBL‐2H3 cells through blocking MAPK signaling pathways. The results suggest that ramalin modulates the production of immune mediators by inhibiting the nuclear factor‐kappa B and MAPK signaling pathways. Taken together, ramalin effectively attenuated the development of AD and promoted the mitigating effects on Th2 cell‐mediated immune responses and the production of inflammatory mediators in mast cells and keratinocytes. Thus, ramalin may be a potential therapeutic agent for AD. Copyright © 2016 John Wiley & Sons, Ltd.     

Inhibitory activity of Chrysanthemi sibirici herba extract on RBL-2H3 mast cells and compound 48/80-induced anaphylaxis

The effects of extracts from various oriental medicinal herbs on mast cell-mediated allergic reaction were investigated. Among them, Chrysanthemi sibirici herba ethanol extract exerted the potent inhibitory activity on antigen-induced degranulation in RBL-2H3 mast cells. Chrysanthemi sibirici herba dose-dependently inhibited DNP-BSA or compound 48/80-induced degranulation in RBL-2H3 mast cells, with IC(50) values of approximately 49 microg/ml and 76 microg/ml, respectively. This extract strongly suppressed compound 48/80-induced systemic anaphylaxis by 48.7% at a dose of 300 mg/kg in mice. Chrysanthemi sibirici herba also inhibited the expression of TNF-alpha and the activation of the MAP kinase, ERK1/2, which is critical for the production of inflammatory cytokines in mast cells, as indicated by the suppression of activating phosphorylation of ERK1/2. These results lead us to conclude that Chrysanthemi sibirici herba may be used clinically to treat various allergic diseases.     

Neohesperidin suppresses IgE‐mediated anaphylactic reactions and mast cell activation via Lyn‐PLC‐Ca2+ pathway

Mast cells play an essential role in IgE‐FcεR1‐mediated allergic diseases. Citrus aurantium is a prolific source of flavonoids with various biological activities, including anti‐inflammatory, antioxidant, and anti‐tumor efficacies. Neohesperidin is a novel flavonoid isolated from the leaves of C. aurantium. In this study, the anti‐allergic and anti‐inflammatory potentials of neohesperidin were investigated along with its molecular mechanism. The anti‐anaphylactic activity of neohesperidin was evaluated through hind paw extravasation study in mice. Calcium imaging was used to assess intracellular Ca²⁺ mobilization. The levels of cytokines and chemokines were measured using enzyme immunoassay kits. Western blotting was used to explore the related molecular signaling pathways. Neohesperidin suppressed IgE‐induced mast cell activations, including degranulation and secretion of cytokines and eicosanoids through inhibiting phosphorylation of Lyn kinase. Neohesperidin inhibited the release of histamine and other proinflammatory cytokines through a mast cell‐dependent passive cutaneous anaphylaxis animal model. Histological studies demonstrated that neohesperidin substantially inhibited IgE‐induced cellular infiltration and attenuated mast cell activation in skin tissue. In conclusion, our study revealed that neohesperidin could inhibit allergic responses in vivo and in vitro, and the molecule may be regarded as a novel agent for preventing mast cell‐immediate and delayed allergic diseases.     

Effects of taraxasterol on iNOS and COX-2 expression in LPS-induced RAW 264.7 macrophages

Ethnopharmacological relevance

Taraxasterol was isolated from the Chinese medicinal herb Taraxacum officinale which has been frequently used as a remedy for inflammatory diseases. Our previous study has shown that taraxasterol inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in RAW 264.7 macrophages. To elucidate the underlying mechanism responsible for these effects, in the present study, we investigated the effects of taraxasterol on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, and mitogen-activated protein kinases (MAPKs) signaling pathway in LPS-induced RAW 264.7 macrophages.

Materials and methods

RAW 264.7 cells were pretreated with 2.5, 5 and 12.5 μg/ml of taraxasterol 1 h prior to treatment with 1 μg/ml of LPS. The mRNA expression levels of iNOS and COX-2 were examined by RT-PCR. The protein expression levels of iNOS and COX-2, and the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), p38 and c-Jun N-terminal kinase (JNK) MAPKs were measured by Western blot.

Results

The mRNA and protein expression levels of iNOS and COX-2 were inhibited by taraxasterol in a concentration-dependent manner. Further studies revealed that taraxasterol suppressed the phosphorylation of ERK1/2 and p38 in LPS-induced RAW 264.7 macrophages.

Conclusions

These results indicate that taraxasterol inhibits iNOS and COX-2 expression by blocking ERK1/2 and p38 MAPKs signaling pathway.