Brian Chi-Yan Cheng

A herbal formula consisting of Rosae Multiflorae Fructus and Lonicerae Japonicae Flos inhibits inflammatory mediators in LPS-stimulated RAW 264.7 macrophages

ETHNOPHARMACOLOGICAL RELEVANCE A herbal formula (RL) consisting of Rosae Multiflorae Fructus (Yingshi) and Lonicerae Japonicae Flos (Jinyinhua) has been traditionally used to treat inflammatory disorders. This study aims to investigate the anti-inflammatory mode and mechanism of action of the ethanol extract of RL so as to provide a pharmacological basis for the use of RL in treating inflammatory diseases. MATERIALS AND METHOD RL consisting of Yingshi and Jinyinhua (in 5:3 ratio) was extracted using absolute ethanol. We investigated its effects on nitric oxide (NO), interleukin-6 (IL-6), tumour necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), mitogen-activated protein kinases (MAPKs) and nuclear factor κB (NFκB) in mouse RAW 264.7 macrophages activated with lipopolysaccharide (LPS). RESULTS RL could decrease the secretion of NO, IL-6 and TNF-α into the culture medium and the cellular protein levels of iNOS and COX-2, which were associated with the reduction of the phosphorylation/activation of JNK and p38, and the inhibition of the transcriptional activity of NF-κB. CONCLUSIONS The present study demonstrated an inhibitory effect of RL on the inflammatory mediators regulated by the NF-κB and MAPK signalling pathways in LPS-stimulated RAW 264.7 macrophages, providing a pharmacological basis for RL in the control of inflammatory disorders.

Inhibition of STAT3 signalling contributes to the antimelanoma action of atractylenolide II

Our previous studies showed that atractylenolide II (AT‐II) has antimelanoma effects in B16 melanoma cells. In this study, we investigated the involvement of STAT3 signalling in the antimelanoma action of AT‐II. Daily administration of AT‐II (12.5, 25 mg/kg, i.g.) for 14 days significantly inhibited tumor growth in a B16 xenograft mouse model and inhibited the activation/phosphorylation of STAT3 and Src in the xenografts. In B16 and A375 cells, AT‐II (20, 40 μm) treatment for 48 h dose‐dependently reduced protein expression levels of phospho‐STAT3, phospho‐Src, as well as STAT3‐regulated Mcl‐1 and Bcl‐xL. Overexpression of a constitutively active variant of STAT3, STAT3C in A375 cells diminished the antiproliferative and apoptotic effects of AT‐II. These data suggest that inhibition of STAT3 signalling contributes to the antimelanoma action of AT‐II. Our findings shed new light on the mechanism of action underlying the antimelanoma effects of AT‐II and provide further pharmacological basis for developing AT‐II as a novel melanoma chemopreventive/chemotherapeutic agent.

A herbal formula comprising Rosae Multiflorae Fructus and Lonicerae Japonicae Flos inhibits the production of inflammatory mediators and the IRAK-1/TAK1 and TBK1/IRF3 pathways in RAW 264.7 and THP-1 cells.

ETHNOPHARMACOLOGICAL RELEVANCE As documented in the Chinese Materia Medica Grand Dictionary (), a herbal formula (RL) consisting of Rosae Multiflorae Fructus (multiflora rose hips) and Lonicerae Japonicae Flos (Japanese honeysuckle flowers) has traditionally been used in treating inflammatory disorders. RL was previously reported to inhibit the expression of various inflammatory mediators regulated by NF-κB and MAPKs that are components of the TLR4 signalling pathways. AIM OF THE STUDY This study aims to provide further justification for clinical application of RL in treating inflammatory disorders by further delineating the involvement of the TLR4 signalling cascades in the effects of RL on inflammatory mediators. MATERIALS AND METHODS RL consisting of Rosae Multiflorae Fructus and Lonicerae Japonicae Flos (in 5:3 ratio) was extracted using absolute ethanol. We investigated the effect of RL on the production of cytokines and chemokines that are regulated by three key transcription factors of the TLR4 signalling pathways AP-1, NF-κB and IRF3 in LPS-stimulated RAW264.7 cells using the multiplex biometric immunoassay. Phosphorylation of AP-1, NF-κB, IRF3, IκB-α, IKKα/β, Akt, TAK1, TBK1, IRAK-1 and IRAK-4 were examined in LPS-stimulated RAW264.7 cells and THP-1 cells using Western blotting. Nuclear localizations of AP-1, NF-κB and IRF3 were also examined using Western blotting. RESULTS RL reduced the secretion of various pro-inflammatory cytokines and chemokines regulated by transcription factors AP-1, NF-κB and IRF3. Phosphorylation and nuclear protein levels of these transcription factors were decreased by RL treatment. Moreover, RL inhibited the activation/phosphorylation of IκB-α, IKKα/β, TAK1, TBK1 and IRAK-1. CONCLUSIONS Suppression of the IRAK-1/TAK1 and TBK1/IRF3 signalling pathways was associated with the effect of RL on inflammatory mediators in LPS-stimulated RAW264.7 and THP-1 cells. This provides further pharmacological basis for the clinical application of RL in the treatment of inflammatory disorders.

A herbal formula comprising Rosae Multiflorae Fructus and Lonicerae Japonicae Flos, attenuates collagen-induced arthritis and inhibits TLR4 signalling in rats

RL, a traditional remedy for Rheumatoid arthritis (RA), comprises two edible herbs, Rosae Multiflorae Fructus and Lonicerae Japonicae Flos. We have reported that RL could inhibit the production of inflammatory mediators in immune cells. Here we investigated the effects and the mechanism of action of RL in collagen-induced arthritis (CIA) rats. RL significantly increased food intake and weight gain of CIA rats without any observable adverse effect; ameliorated joint erythema and swelling; inhibited immune cell infiltration, bone erosion and osteophyte formation in joints; reduced joint protein expression levels of TLR4, phospho-TAK1, phospho-NF-κB p65, phospho-c-Jun and phospho-IRF3; lowered levels of inflammatory factors (TNF-α, IL-6, IL-1β, IL-17A and MCP-1 in sera and TNF-α, IL-6, IL-1β and IL-17A in joints); elevated serum IL-10 level; reinvigorated activities of antioxidant SOD, CAT and GSH-Px in the liver and serum; reduced Th17 cell proportions in splenocytes; inhibited splenocyte proliferation and activation; and lowered serum IgG level. In conclusion, RL at nontoxic doses inhibited TLR4 signaling and potently improved clinical conditions of CIA rats. These findings provide further pharmacological justifications for the traditional use of RL in RA management.

The genus Rosa and arthritis: Overview on pharmacological perspectives

The genus Rosa (roses) has long been used in traditional or folk medicine worldwide for the treatment of various types of arthritis including rheumatoid arthritis and osteoarthritis. The active constituents of Rosa spp., such as flavonoids, triterpenoids, and phytosterols, could act on different targets in the NF-κB signalling pathway, inhibit pro-inflammatory enzymes (e.g. MMPs and COX-2), lower the production of inflammatory cytokines and chemokines (e.g. TNF-α, IL-1β, IL-6, CCL5), and reduce oxidative stress, which in turn suppress inflammatory processes. Preclinical and clinical studies have demonstrated that these species possess analgesic, anti-arthritic, anti-inflammatory, anti-oxidative and bone-preserving activities. This review presents comprehensive overview of the mode and mechanism of action of various extracts, preparations, and active constituents from this genus. The dynamic beneficial effects of the products prepared from this genus in arthritis management are summarized. The Rosa genus is a treasure waiting for further exploration by researchers interested in the development of safe and effective anti-arthritic agents.

Standardization of the manufacturing procedure for Pinelliae Rhizoma Praeparatum cum Zingibere et Alumine

ETHNOPHARMACOLOGICAL RELEVANCE Pinelliae Rhizoma (PR), the dried tuber of Pinellia ternata (Thunb.) Breit., is a traditional Chinese medicinal herb. It is commonly used for treating cancer, cough and phlegm. To treat cancer, Chinese medicine practitioners often use raw PR; while to treat cough and phlegm, they usually use Pinelliae Rhizoma Praeparatum cum Zingibere et Alumine (PRZA, raw PR processed with ginger juice and alumen as adjuvant materials). Currently, the producing protocol of PRZA varies greatly among different places in China. This study aims to standardize the manufacturing procedure for PRZA. We also evaluated the impact of processing on the bioactivities and chemical profile of raw PR. MATERIALS AND METHODS We used the orthogonal design to optimize the manufacturing procedure of PRZA at bench scale, and validated the optimized procedure in pilot-scale production. The MTT assay was used to compare the cytotoxicities of raw PR and PRZA in hepatocellular carcinoma HepG2 cells. Animal models (ammonia liquor-induced cough model and phenol red secretion model) were used to compare the antitussive and expectorant effects of raw PR and PRZA, respectively. The chemical profiles of raw PR and PRZA samples were compared using a newly developed ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS) method. RESULTS The standardized manufacturing procedure for PRZA is as follows: soak raw PR in water until the center of the cut surface is devoid of a dry core, after that, boil the herb in water (for each 100kg raw PR, 12.5kg alumen and 25L freshly squeezed ginger juice are added) for 6h, and then take out and dry them. The cytotoxicity of PRZA was less potent than that of raw PR. Intragastric administration of raw PR or PRZA demonstrated antitussive and expectorant effects in mice. These effects of PRZA were more potent than that of raw PR at the dose of 3g/kg. By comparing the chemical profiles, we found that six peaks were lower, while nine other peaks were higher in PRZA than in raw PR. Six compounds corresponding to six individual changed peaks were tentatively identified by matching with empirical molecular formulae and mass fragments. CONCLUSION The manufacturing procedure for PRZA was standardized. This protocol can be used for PRZA industrial production. The bioactivity assay results of raw PR and PRZA (produced using the standardized protocol) support the common practice for the clinical applications of these two decoction pieces. Moreover, raw PR and PRZA showed different chemical profiles. Further studies are warranted to establish the relationship between the alteration of chemical profiles and the changes of medicinal properties caused by processing.

Comparison of the toxicities, bioactivities and chemical profiles of raw and processed Xanthii Fructus

BackgroundAlthough toxic, the Chinese medicinal herb Xanthii Fructus (XF) is commonly used to treat traditional Chinese medicine (TCM) symptoms that resemble cold, sinusitis and arthritis. According to TCM theory, stir-baking (a processing method) can reduce the toxicity and enhance the efficacy of XF.MethodsCytotoxicities of raw XF and processed XF (stir-baked XF, SBXF) were determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay in normal liver derived MIHA cells. Nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) mRNA expression were measured by the Griess reagent and quantitative real-time PCR, respectively. The chemical profiles of XF and SBXF were compared using an established ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS) method.ResultsSBXF was less toxic than XF in MIHA cells. Both XF and SBXF could reduce NO production and iNOS mRNA expression in lipopolysaccharide-stimulated RAW 264.7 macrophages. Interestingly, the effects of SBXF were more potent than XF in the macrophages. By comparing the chemical profiles, we found that seven peaks were lower, while nine other peaks were higher in SBXF than in XF. Eleven compounds including carboxyatractyloside, atractyloside and chlorogenic acid corresponding to eleven individual changed peaks were tentatively identified by matching with empirical molecular formulae and mass fragments, as well as literature data.ConclusionOur study showed that stir-baking significantly reduced the cytotoxicity and enhanced the bioactivity of XF; moreover, with a developed UPLC/Q-TOF-MS method we differentiated XF and SBXF by their chemical profiles. Further studies are warranted to establish the relationship between the alteration of chemical profiles and the changes of medicinal properties caused by stir-baking.

An ethanolic extract of the aerial part of Siegesbeckia orientalis L. inhibits the production of inflammatory mediators regulated by AP-1, NF-κB and IRF3 in LPS-stimulated RAW 264.7 cells

Herba Siegesbeckiae (HS, the dried aerial part of Siegesbeckia orientalis L.) is a commonly used traditional Chinese medicinal herb for treating inflammatory diseases. HS has been reported to exert anti-inflammatory effects by inhibiting the MAPKs and NF-κB pathways, the downstream effectors of TLR4 signalling. This study aims to further investigate the involvement of TLR4 signalling cascades in the effects of an ethanolic extract of HS (HS for short) on inflammatory mediators in murine macrophages. HS was extracted using 50% ethanol. Lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were used as the cell model. ELISA was used to detect cytokine/chemokine secretion. Real time-PCR and immunoblotting were used to examine mRNA and protein levels, respectively. We observed that HS dose-dependently inhibited the secretion of PGE2, MCP-1, MIP-1α and RANTES, and down-regulated mRNA levels of iNOS, COX-2, IL-1β, IL-6, TNF-α, mPGES-1, MCP-1, MIP-1α and RANTES in LPS-stimulated RAW264.7 cells. HS did not affect the protein levels of TAK1, TBK1, PI3K, Akt, IKK, c-Jun, c-Fos and IRF3, while, dose-dependently decreased levels of their phosphorylated forms. The protein levels of IRAK1 and IRAK4 were upregulated, while those of TRAF6 and TRAF3 were downregulated by HS. Moreover, the nuclear protein levels of AP-1, NF-κB and IRF3 were dose-dependently decreased by HS. These results indicate that suppression of the IRAK4/MAPKs/AP-1, IRAK4/MAPKs/NF-κB, IRAK4/PI3K/NF-κB and TRAF3/TBK1/IRF3 pathways is associated with the inhibitory effects of HS on inflammatory mediators in LPS-stimulated RAW264.7 cells. This study provides a pharmacological basis for the clinical application of this herb in the treatment of inflammatory disorders.

Sensitization of melanoma cells to alkylating agent-induced DNA damage and cell death via orchestrating oxidative stress and IKKβ inhibition

Nitrosourea represents one of the most active classes of chemotherapeutic alkylating agents for metastatic melanoma. Treatment with nitrosoureas caused severe systemic side effects which hamper its clinical use. Here, we provide pharmacological evidence that reactive oxygen species (ROS) induction and IKKβ inhibition cooperatively enhance nitrosourea-induced cytotoxicity in melanoma cells. We identified SC-514 as a ROS-inducing IKKβ inhibitor which enhanced the function of nitrosoureas. Elevated ROS level results in increased DNA crosslink efficiency triggered by nitrosoureas and IKKβ inhibition enhances DNA damage signals and sensitizes nitrosourea-induced cell death. Using xenograft mouse model, we confirm that ROS-inducing IKKβ inhibitor cooperates with nitrosourea to reduce tumor size and malignancy in vivo. Taken together, our results illustrate a new direction in nitrosourea treatment, and reveal that the combination of ROS-inducing IKKβ inhibitors with nitrosoureas can be potentially exploited for melanoma therapy.

Dingchuan tang essential oil inhibits the production of inflammatory mediators via suppressing the IRAK/NF-κB, IRAK/AP-1, and TBK1/IRF3 pathways in lipopolysaccharide-stimulated RAW264.7 cells

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.