Flavonoids interfere with NLRP3 inflammasome activation.

NOD-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome is a component of innate immunity, and is responsible for producing mature IL-1ß and -18. Several flavonoids were found to affect inflammasome pathway, but the mechanism of action is still obscure. To elucidate the effects on NLRP3 inflammasome pathway and to determine the structure-activity relationships, NLRP3 inflammasome in differentiated THP-1 cells was activated via treatment with monosodium urate (MSU) crystals. Levels of mature IL-1ß, NLRP3 inflammasome components and apoptosis-associated speck-like protein containing a CARD (caspase recruitment domain) (ASC) oligomerization were investigated and the mechanisms of action were also elucidated. Among the 56 flavonoids initially tested, only flavone, 2',4'-dihhydroxyflavone, 3',4'-dichloroflavone, 4',5,7-trihydroxyflavone (apigenin), 3,4',5,7-tetrahydroxyflavone (kaempferol) and 3,3',4',5,7-pentahydroxyflavone (quercetin) significantly inhibited IL-1ß production at 10 µM. Apigenin, kaempferol and 3',4'-dichloroflavone inhibited ASC oligomerization without affecting the ASC level in cell lysates. Apigenin also inhibited absent in melanoma 2 (AIM2) inflammasome-related pathway, but not NLR family CARD domain-containing protein 4 (NLRC4) inflammasome activation. The action of apigenin on NLRP3 inflammasome activation is mediated partly via inhibition of phosphorylation of spleen tyrosine kinase/protein tyrosine kinase 2 (Syk/Pyk2) pathway. Furthermore, orally administered apigenin (100 mg/kg) strongly reduced the number of neutrophils and monocytes in MSU-induced peritonitis in mice. The present study, for the first time, demonstrated the structure-activity profiles of flavonoids in NLRP3 inflammasome activation and mechanisms of cellular action. Certain flavonoids including apigenin are expected to ameliorate the inflammatory symptoms in autoinflammatory diseases associated with NLRP3 inflammasome activation.

Aurantio-obtusin, an anthraquinone from cassiae semen, ameliorates lung inflammatory responses.

The purpose of the present study is to find the natural compound(s) having a therapeutic potential to treat lung inflammatory disorders. In our screening procedure, the methanol extract of the seeds of Cassia obtusifolia (cassiae semen) inhibited inducible nitric oxide synthase-catalyzed nitric oxide production in alveolar macrophages (MH-S). From the extract, 8 major anthraquinone derivatives were successfully isolated. They are chrysophanol, physcion, 2-hydroxy-emodin 1-methyl ether, obtusifolin, obtusin, aurantio-obtusin, chryso-obtusin, and gluco-obtusifolin, among which aurantio-obtusin (IC50  = 71.7 µM) showed significant inhibitory action on nitric oxide production from lipopolysaccharide-treated MH-S cells, mainly by downregulation of inducible nitric oxide synthase expression. This down-regulatory action of aurantio-obtusin was mediated at least in part via interrupting c-Jun N-terminal kinase/IκB kinase/nuclear transcription factor-κB pathways. Aurantio-obtusin also inhibited IL-6 production in IL-1ß-treated lung epithelial cells, A549. Importantly, this compound (10 and 100 mg/kg) by oral administration attenuated lung inflammatory responses in a mouse model of lipopolysaccharide-induced acute lung injury. Therefore, it is for the first time found that aurantio-obtusin may have a therapeutic potential for treating lung inflammatory diseases.

State-of-the-art separation of ginsenosides from Korean white and red ginseng by countercurrent chromatography.

Ginseng (Panax ginseng C. A. Meyer) has been one of the most popular herbs used for nutritional and medicinal purposes by the people of eastern Asia for thousands of years. Ginsenosides, the mostly widely studied chemical components of ginseng, are quite different depending on the processing method used. A number of studies demonstrate the countercurrent chromatography (CCC) separation of ginsenosides from several sources; however, there is no single report demonstrating a one-step separation of all of these ginsenosides from different sources. In the present study, we have successfully developed an efficient CCC separation methodology in which the flow-rate gradient technique was coupled with a new solvent gradient dilution strategy for the isolation of ginsenosides from Korean white (peeled off dried P. ginseng) and red ginseng (steam-treated P. ginseng). The crude samples were initially prepared by extraction with butanol and were further purified with CCC using solvent gradients composed of methylene chloride-methanol-isopropanol-water (different ratios, v/v). Gas chromatography coupled with flame ionization detector was used to analyze the components of the two-phase solvent mixture. Each phase solvent mixture was prepared without presaturation, which saves time and reduces the solvent consumption. Finally, 13 ginsenosides have been purified from red ginseng with the new technique, including Rg1, Re, Rf, Rg2, Rb1, Rb2, Rc, Rd, Rg3, Rk1, Rg5, Rg6, and F4. Meanwhile, eight ginsenosides have been purified from white ginseng, including Rg1, Re, Rf, Rh1, Rb1, Rb2, Rc, and Rd by using a single-solvent system. Thus, the present technique could be used for the purification of ginsenosides from all types' ginseng sources. To our knowledge, this is the first report involving the separation of ginsenoside Rg2 and Rg6 and the one-step separation of thirteen ginsenosides from red ginseng by CCC.

The rhizomes of Alisma orientale and alisol derivatives inhibit allergic response and experimental atopic dermatitis.

The 70% ethanol extract of the rhizome of Alisma orientale (Alismatis rhizome) (AOE) was prepared and found to significantly inhibit 5-lipoxygenase (5-LOX)-catalyzed leukotriene (LT) production from rat basophilic leukemia (RBL)-1 cells and ß-hexosaminidase release by antigen-stimulated RBL-2H3 cells. It also attenuated delayed-type hypersensitivity (DTH) reaction in mice. Among the three major triterpene constituents isolated (i.e., alisol B, alisol B 23-acetate, alisol C 23-acetate) as active principles, alisol B and its 23-acetate strongly and significantly inhibited LT production and ß-hexosaminidase release between 1-10 µM. On the other hand, all these alisol derivatives significantly and strongly inhibited DTH response after oral administration. In addition, AOE (200 mg/kg/d) was for the first time found to considerably alleviate hapten-induced dermatitis symptoms in NC/Nga mice, an animal model of atopic dermatitis. These results indicate that alisol derivatives possess inhibitory activities on immediate-type as well as delayed-type hypersensitivity reactions and may contribute to the anti-allergic action of AOE.

The Long Search for Pharmacologically Useful Anti-Inflammatory Flavonoids and Their Action Mechanisms: Past, Present, and Future.

Flavonoids are known to exert anti-inflammatory effects. Their pharmacological activities have been proved using various in vitro and in vivo models. Although their action spectrum and potencies are not adequate to alleviate acute inflammatory disorders, they have the potential to treat chronic inflammatory diseases. Recent investigations have revealed that inflammatory processes are involved in many disease processes and conditions. Some examples are skin disorders, cartilage diseases, metabolic inflammatory diseases, and aging. The effects of flavonoids on these disorders have been examined. Several possible application areas for flavonoids have been studied. Local treatment of these disorders with flavonoids is favorable to avoid systemic transformation. In this review, the findings based on the experimental results from my laboratory are summarized and the future possibility of using flavonoids clinically is discussed.

Effects of flavonoids on matrix metalloproteinase-13 expression of interleukin-1ß-treated articular chondrocytes and their cellular mechanisms: inhibition of c-Fos/AP-1 and JAK/STAT signaling pathways.

To identify the therapeutic potential for cartilage degradation and its action mechanisms, the effects of naturally-occurring flavonoids on matrix metalloproteinase-13 (MMP-13) induction were examined in the human chondrocyte cell line SW1353. Flavones including apigenin and wogonin strongly inhibited MMP-13 induction in interleukin (IL)-1ß-treated SW1353 cells, while flavonols such as kaempferol, quercetin, and flavanone (naringenin) did not at 5 - 25 µM. Apigenin and wogonin primarily inhibit MMP-13 by blocking the c-Fos / activator protein-1 (AP-1) and Janus kinase 2 (JAK2) / signal transducer and activator of transcription 1/2 (STAT1/2) pathways, but not nuclear factor-κB (NF-κB) signaling. Apigenin was also shown to inhibit extracellular matrix degradation in rabbit cartilage culture. The following study using some synthetic flavones demonstrated that A-ring C-5,7-dihydroxyl and B-ring dihydroxyl substitution at C-2,3, C-2,4, or C-3,4 are important for the suppression of MMP-13 expression. Among these flavones, 2',3',5,7-tetrahydroxyflavone also inhibited both the c-Fos/AP-1 and STAT1/2 pathways. Taken together, these results indicate that certain flavonoids, especially flavones, inhibit MMP-13 expression in IL-1ß-treated chondrocytes, at least in part, by suppressing the c-Fos/AP-1 and JAK2/STAT1/2 pathways. Furthermore, these findings suggest that some flavonoids have the potential for protecting against collagen matrix breakdown in the cartilage of diseased tissues such as those found in arthritic disorders.

Development of a Sleeping Beauty-based telomerase gene delivery system for hepatocytes.

Telomerase is a particular reverse transcriptase that not only synthesizes and maintains the telomere but also promotes the proliferation of resting cells and prevents cellular senescence. The advantages of the Sleeping Beauty transposon system include prolonged transgene expression without eliciting an immunogenic response, no possibility of RCV and ease of construction. Tissue-specific therapeutic gene expression is extremely important in gene therapy, because non-specific expression can cause an immune response of the transduced cells that can severely limit the stability of the transgene. The SB system containing the telomerase gene controlled by two chimeric transthyretin (TTR) gene promoters/enhancers, the human alcohol dehydrogenase gene promoter (ADHp), and the SV40 viral enhancer (SV40VE) was constructed in order to activate hepatocyte cell growth. The higher expression was achieved using these elements and FACS analysis showed that this system was effective in hepatocyte targeted gene therapy. Our new SB mediated telomerase delivery system for hepatocytes can be used in human gene therapy applications.

Downregulation of matrix metalloproteinase-13 by the root extract of Cyathula officinalis Kuan and its constituents in IL-1ß-treated chondrocytes.

The roots of Cyathula officinalis Kuan are widely used in Chinese medicine for the treatment of inflammatory disorders. Here, the ability of C. officinalis Kuan to downregulate matrix metalloproteinase (MMP)-13 was examined since MMP-13 is an important enzyme for the degradation of the cartilage collagen matrix, especially under arthritic conditions. The ethanol extract of C. officinalis Kuan as well as the N-hexane and chloroform soluble fractions were found to potently inhibit MMP-13 induction in IL-1 ß-treated SW1353 cells, a human chondrosarcoma cell line, at 50-200 µg/mL. Activity-guided separation led to the isolation of six compounds, palmitic acid (1), ß-sitosterol (2), α-spinasterol (3), atractylenolide I (4), 1,3-diacetoxy-tetradeca-6E,12E-dien-8,10-dyn (5), and N-trans-feruloyl-3-methyldopamine (6). Among these, 4 and 5 exhibited MMP-13 downregulating activity in IL-1 ß-treated SW1353 cells. And 4 also showed anti-oedematous activity against λ-carageenan-induced paw edema in mice at 20-200 mg/kg, p. o. The results of this study provide information that can help elucidate the action mechanism of C. officinalis Kuan. In addition, the results presented here suggest that C. officinalis Kuan and its constituents may have the potential for chondroprotection against cartilage degrading disorders.

Inhibition of experimental atopic dermatitis by rhubarb (rhizomes of Rheum tanguticum) and 5-lipoxygenase inhibition of its major constituent, emodin.

The antiallergic activity of rhubarb and its constituents, anthraquinones, has been reported previously. For further evaluation of the antiallergic activity, a 70% ethanol extract of the rhizomes of Rheum tanguticum (RTE) was prepared and its inhibitory activity on an animal model of atopic dermatitis (AD) was examined for the first time. Oral administration of RTE (30-300 mg/kg/day) for 5 weeks significantly inhibited hapten-induced dermatitis in NC/Nga mice based on the skin severity score. In addition, treatment with RTE at 100 mg/kg/day also reduced the numbers of white blood cells, neutrophils and eosinophils in the blood, and led to a significant reduction in the IgE concentration in the serum. In rat basophilic leukemia (RBL)-1 cells, RTE inhibited 5-lipoxygenase (5-LOX)-catalysed leukotriene production (IC(50) = 43.6 µg/mL). Among the anthraquinone derivatives isolated, emodin strongly inhibited this parameter (IC(50) = 4.3 µM). Taken together, these findings suggest that rhubarb exerts inhibitory activity against AD, and that the 5-LOX inhibitory activity of its major constituent, emodin, may contribute to this inhibitory action.

Interruption of Helicobacter pylori-Induced NLRP3 Inflammasome Activation by Chalcone Derivatives.

Helicobacter pylori causes chronic gastritis through cag pathogenicity island (cagPAI), vacuolating cytotoxin A (VacA), lipopolysaccharides (LPS), and flagellin as pathogen-related molecular patterns (PAMPs), which, in combination with the pattern recognition receptors (PRRs) of host cells promotes the expression and secretion of inflammation-causing cytokines and activates innate immune responses such as inflammasomes. To identify useful compounds against H. pylori-associated gastric disorders, the effect of chalcone derivatives to activate the nucleotide-binding oligomerization domain (NOD)-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome was examined in an H. pylori-infected human monocytic THP-1 cell line in this study. Among the five synthetic structurally-related chalcone derivatives examined, 2'-hydroxy-4',6'-dimethoxychalcone (8) and 2'-hydroxy-3,4,5- trimethoxychalcone (12) strongly blocked the NLRP3 inflammasome in H. pylori-infected THP-1 cells. At 10 µM, these compounds inhibited the production of active IL-1ß, IL-18, and caspase-1, and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) oligomerization, but did not affect the expression levels of NLRP3, ASC, and pro-caspase-1. The interruption of NLRP3 inflammasome activation by these compounds was found to be mediated via the inhibition of the interleukin-1 receptor-associated kinase 4 (IRAK4)/IκBα/NF-κB signaling pathway. These compounds also inhibited caspase-4 production associated with non-canonical NLRP3 inflammasome activation. These results show for the first time that certain chalcones could interrupt the activation of the NLRP3 inflammasome in H. pylori-infected THP-1 cells. Therefore, these chalcones may be helpful in alleviating H. pylori-related inflammatory disorders including chronic gastritis.

Improvement of testosterone deficiency by fermented Momordica charantia extracts in aging male rats.

This study evaluated the efficacy of Momordica charantia (MC; bitter melon) extracts against andropause symptoms. We fermented MC with Lactobacillus plantarum and verified the ability of the fermented MC extracts (FMEs) to control testosterone deficiency by using aging male rats as an animal model of andropause. FME administration considerably increased total and free testosterone levels, muscle mass, forced swimming time, and total and motile sperm counts in aging male rats. In contrast, sex hormone-binding globulin, retroperitoneal fat, serum cholesterol, and triglyceride levels were significantly reduced in the treated groups compared to the non-treated control aging male rats. Furthermore, we observed that FME enhanced the expression of testosterone biosynthesis-related genes but reduced the expression of testosterone degradation-related genes in a mouse Leydig cell line. These results suggest that FME has effective pharmacological activities that increase and restore free testosterone levels and that FME may be employed as a promising natural product for alleviating testosterone deficiency syndrome. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-020-00872-x.

1,5-Diarylimidazoles with strong inhibitory activity against COX-2 catalyzed PGE2 production from LPS-induced RAW 264.7 cells.

A series of 1,5-diarylimidazoles with 4-methylsulfonylphenyl group were prepared and evaluated for the inhibitory activities against COX-2 catalyzed PGE(2) production from LPS-induced RAW 264.7 cells. Most of synthesized 1,5-diarylimidazoles exhibited strong inhibitory activities regardless of the position of the 4-methylsulfonylphenyl group. The 1,5-diarylimidazoles with a halogen atom (3c-3h, 3n-3p) gave mostly excellent inhibitory activities regardless of the position and species of the halogen atom. Whereas the 1,5-diarylimidazoles with two fluorine atoms (3k, 3l, 3r, 3s) showed rather reduced inhibitory activities.

Flavonoids from Scutellaria baicalensis inhibit senescence-associated secretory phenotype production by interrupting IκBζ/C/EBPß pathway: Inhibition of age-related inflammation.

BACKGROUND: Prolonged exposure to the senescence-associated secretory phenotype (SASP) with age leads to chronic low-grade inflammation in neighboring cells and tissues, causing many chronic degenerative diseases. PURPOSE: The effects on SASP production of the ethanol extract from Scutellaria radix and 17 isolated flavonoid constituents were examined in vitro and in vivo. METHODS: Cellular senescence was induced by bleomycin. Expression of the SASP and cell signaling molecules was detected using ELISA, RT-qPCR, Western blotting, and immunofluorescence staining. To investigate the in vivo effects, 21-month-old aged rats were used. RESULTS: The ethanol extract and 5 compounds including 1 (Oroxylin A; 5,7-dihydroxy-6-methoxyflavone), 5 (2',6',5,7-tetrahydroxy-8-methoxyflavone), 8 (2',5,7-trihydroxyflavone), 10 (2',5,7-trihydroxy-8-methoxyflavone) and 11 (2',5,7-trihydroxy-6-methoxyflavone) potently reduced IL-6 and IL-8 production and gene expression of the SASP, including IL-1α, IL-1ß, IL-6, IL-8, GM-CSF, CXCL1, MCP-2, and MMP-3. This finding indicates the important role of the B-ring 2'­hydroxyl group in flavonoid molecules. Furthermore, compounds 8 and 11, the strongest SASP inhibitors, decreased the expression of IκBζ and C/EBPß protein without affecting either BrdU uptake or the expression of senescence markers, such as pRb and p21. Finally, the oral administration of compound 8 to aged rats at 2 and 4 mg/kg/day for 10 days significantly inhibited the gene expression of SASP and IκBζ in kidneys. This is the first report of the strong SASP inhibitory action of flavonoids from Scutellaria radix on in vitro and in vivo senescence models. The inhibitory action was shown to be mediated mainly by interfering with the IκBζ/C/EBPß signaling pathway. CONCLUSION: Targeting production of the SASP using flavonoids from Scutellaria radix or its extract might help reduce low-grade sterile inflammation and control age-related diseases.

Potential Moracin M Prodrugs Strongly Attenuate Airway Inflammation In Vivo.

This study aims to develop new potential therapeutic moracin M prodrugs acting on lung inflammatory disorders. Potential moracin M prodrugs (KW01-KW07) were chemically synthesized to obtain potent orally active derivatives, and their pharmacological activities against lung inflammation were, for the first time, examined in vivo using lipopolysaccharide (LPS)-induced acute lung injury model. In addition, the metabolism of KW02 was also investigated using microsomal stability test and pharmacokinetic study in rats. When orally administered, some of these compounds (30 mg/kg) showed higher inhibitory action against LPSinduced lung inflammation in mice compared to moracin M. Of them, 2-(3,5-bis((dimethylcarbamoyl)oxy)phenyl)benzofuran-6-yl acetate (KW02) showed potent and dose-dependent inhibitory effect on the same animal model of lung inflammation at 1, 3, and 10 mg/kg. This compound at 10 mg/kg also significantly reduced IL-1ß concentration in the bronchoalveolar lavage fluid of the inflamed-lungs. KW02 was rapidly metabolized to 5-(6-hydroxybenzofuran-2-yl)-1,3-phenylene bis(dimethylcarbamate) (KW06) and moracin M when it was incubated with rat serum and liver microsome as expected. When KW02 was administered to rats via intravenous or oral route, KW06 was detected in the serum as a metabolite. Thus, it is concluded that KW02 has potent inhibitory action against LPS-induced lung inflammation. It could behave as a potential prodrug of moracin M to effectively treat lung inflammatory disorders.

Inhibitory Mechanisms of Water Extract of Oplopanax elatus on Lipopolysaccharide-Induced Inflammatory Responses in RAW 264.7 Murine Macrophage Cells.

OBJECTIVE: To study the anti-inflammatory action and cellular mechanism of Oplopanax elatus. METHODS: A hot water extract of OE (WOE) was prepared and a major constituent, syringin, was successfully isolated. Its content in WOE was found to be 214.0 µg/g dried plant (w/w). Their anti-inflammatory activities were examined using RAW 264.7 macrophages and a mouse model of croton oil-induced ear edema. RESULTS: In lipopolysaccharide (LPS)-treated RAW 264.7 cells, a mouse macrophage cell line, WOE was found to significantly and strongly inhibit cyclooxygenase-2 (COX-2)-induced prostaglandin E2 (PGE2) production [half maximal inhibitory concentration (IC50)=135.2 µg/mL] and inducible nitric oxide synthase (iNOS)-induced NO production (IC50=242.9 µg/mL). In the same condition, WOE was revealed to inhibit NO production by down-regulating iNOS expression, mainly by interrupting mitogen activated protein kinases (MAPKs)/activator protein-1 (AP-1) pathway. The activation of all three major MAPKs, p38 MAPK, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase, was inhibited by WOE (50-300 µg/mL). On the other hand, WOE reduced PGE2 production by inhibiting COX-2 enzyme activity, but did not affect COX-2 expression levels. In addition, WOE inhibited the production of proinflammatory cytokines such as interleukin-6 and tumor necrosis factor-α. In croton oil-induced ear edema in mice, oral administration of WOE (50-300 mg/kg) dose-dependently inhibited edematic inflammation. CONCLUSION: Water extract of OE exhibited multiple anti-inflammatory action mechanisms and may have potential for treating inflammatory disorders.

Inhibitory activity of prostaglandin E2 production by the synthetic 2'-hydroxychalcone analogues: Synthesis and SAR study.

A series of 2'-hydroxychalcones has been synthesized and screened for their in vitro inhibitory activities of cyclooxygenase-2 catalyzed prostaglandin production from lipopolysaccharide-treated RAW 264.7 cells. Structure-activity relationship study suggested that inhibitory activity against prostaglandin E(2) production was governed to a greater extent by the substituent on B ring of the chalcone, and most of the active compounds have at least two methoxy or benzyloxy groups on B ring. The relationship between chalcone structures and their PGE(2) inhibitory activities was also interpreted by docking study on cyclooxygenase-2.

Synthesis of biflavones having a 6-O-7'' linkage and effects on cyclooxygenase-2 and inducible nitric oxide synthase.

In order to establish anti-inflammatory potential of biflavonoids, 17 biflavone derivatives having a 6-O-7'' linkage were synthesized and their effects on cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were evaluated. The basic molecule (6-O-7'' biflavone) potently inhibited COX-2-mediated PGE(2) production (IC(50): <2 microM), being less active on iNOS-mediated NO production (IC(50): >50 microM) from lipopolysaccharide-treated RAW 264.7 cells, a mouse macrophage cell line. Generally, the hydroxyl/methoxyl substitution(s) on the basic biflavone (6-O-7'') reduced the inhibitory activity of PGE(2) production, while the effects on NO production were varied. It is suggested that the basic biflavone (6-O-7'') may have a potential for new anti-inflammatory agent.

5-lipoxygenase-inhibitory constituents from Schizandra fructus and Magnolia flos.

In order to establish the antiallergic properties of Schisandra fructus and Magnolia flos, several compounds isolated from these plants were tested for 5-lipoxygenase (5-LOX) inhibitory activity in vitro, for the first time. The compounds including schizandrins, schisandrols, gomisins, fargesin, eudesmin and lirioresinol B dimethyl ether, inhibited 5-LOX-catalysed leukotriene production from A23187-treated rat basophilic leukemia (RBL-1) cells at concentrations of 1-100 microm. In particular, constituents such as schisandrol A and gomisins showed potent inhibitory activity (IC(50)s < 10 microm) on 5-LOX-catalysed leukotriene production, but were much less active on cyclooxygenase-2-catalysed prostaglandin E(2) and inducible nitric oxide-catalysed NO production. These compounds have the potential to be developed as novel antiallergic agents and may contribute to the antiallergic pharmacological use of these plant materials in Chinese medicine.

Inhibition of prostaglandin E2 production by synthetic wogonin analogs.

Effects of wogonin analogs on cyclooxygenase-2 (COX-2) catalyzed prostaglandin E2 production on lipopolysaccharide (LPS)-induced RAW 264.7 cells were investigated. Wogonin analogs were prepared via several different synthetic pathways. Among wogonin analogs tested, 8-halogeno and 8-nitro analogs showed strong inhibitory activities against COX-2 catalyzed PGE2 production from LPS-induced RAW 264.7 cells. Effect of wogonin was largely dependent on structural alteration of the 8-methoxy group.

(-)-Nyasol (cis-hinokiresinol), a norneolignan from the rhizomes of Anemarrhena asphodeloides, is a broad spectrum inhibitor of eicosanoid and nitric oxide production.

To assess the anti-inflammatory activity of constituents from the rhizomes of Anemarrhena asphodeloides, (-)-nyasol {cis-hinokiresinol, 4,4-[1Z,3R]-3-ethenyl-1-propene-1,3-diyl]bisphenol} was isolated and its anti-inflammatory activity was examined in lipopolysaccharide (LPS)-treated RAW 264.7 cells and A23187-treated RBL-1 cells. In vivo activity was measured using carrageenan-induced paw edema assay. At > 1 microM, (-)-nyasol significantly inhibited cyclooxygenase-2 (COX-2)-mediated PGE2 production and inducible nitric oxide synthase (iNOS)-mediated NO production in LPS-treated RAW 264.7 cells, a mouse macrophage-like cell line, but did not affect the expression levels of COX-2 and iNOS. (-)-Nyasol also inhibited 5-lipoxygenase (5-LOX)-mediated leukotriene production in A23187-treated RBL-1 cells. Furthermore, (-)-nyasol potently inhibited carrageenan-induced paw edema in mice (28.6-77.1% inhibition at 24-120 mg/kg). Therefore, (-)-nyasol is a potential new lead compound and may contribute to the anti-inflammatory action of A. asphodeloides, possibly by inhibiting COX-2, iNOS and 5-LOX.