Gold nanoparticles attenuate LPS-induced NO production through the inhibition of NF-kappaB and IFN-beta/STAT1 pathways in RAW264.7 cells.

Macrophage-derived nitric oxide (NO) plays an important role in protection against microbial infection in immune responses. Overproduction of NO by inducible nitric synthase (iNOS) is known to be closely correlated with the pathology of a variety of diseases and inflammations. In this study, we investigated the inhibitory effect of polyethylene glycol coated gold nanoparticles (GNP) on NO production and its molecular mechanism in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. It was found that GNP inhibited LPS-induced NO production and iNOS expression in RAW264.7 cells. Furthermore, GNP suppressed LPS-induced activation of NF-kappaB through the inhibition of Akt activity. GNP also inhibited LPS-induced phosphorylation of signal transducer and activator of transcription 1 (STAT1) via down-regulation of interferon-beta (IFN-beta) expression. Our results suggest that GNP inhibits NO production and iNOS expression through blocking the activation of NF-kappaB and STAT1 in LPS-stimulated RAW264.7 cells.

Enterococcus faecalis EF-2001 protects DNBS-induced inflammatory bowel disease in mice model.

Recent studies have demonstrated the immunomodulatory effects of heat-killed lactic acid bacteria. The aim of this study was to evaluate the protective effect of heat-killed Enterococcus faecalis EF-2001 (EF-2001) on a model of inflammatory bowel disease (IBD). A total of 28 female NC/Nga mice were divided into 4 treatment groups. Controls were fed a normal commercial diet. In the experimental groups, colitis was induced by rectal administration of dinitrobenzene sulfonic acid. Two groups were orally administered 2 and 17 mg/kg EF-2001, respectively. EF-2001 treatment decreased the expression of several cytokines, including cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), interferon (IFN)-γ, interleukin (IL)-1ß, and IL-6 in inflamed colon compared to the DNBS alone group. In addition, EF-2001 suppressed DNBS-induced colonic tissue destruction. Therefore, this study strongly suggests that EF-2001 could alleviate the inflammation associated with mouse IBD.

Effect of Enterococcus faecalis EF-2001 on experimentally induced atopic eczema in mice.

Here, the effects of heat-killed Enterococcus faecalis EF-2001 (EF-2001) on atopic eczema (AE) were assessed. An AE model was established in vivo by repetitious topical exposure to 1-chloro-2,4-dinitrobenzene (CDNB) and dermatophagoidesfarinae extract (DFE) via application on each ear. Mice were administered EF-2001 orally for 4 weeks, dermal and epidermal ear thickness, mast cell infiltration of the ear tissue, and serum IgE and IgG2a levels were evaluated. Moreover, pathogenic cytokines levels of the ears, splenocytes, and cervical lymph nodes were determined. EF-2001 reduced AE symptoms grounded in the ear thickness, histopathological analysis, and serum IgE levels. Furthermore, EF-2001 attenuated mast cell infiltration in the ears and CDNB/DFE-induced various pathogenic cytokines levels of the ears, splenocytes and cervical lymph nodes. Thus, our data suggested that EF-2001 may have potential medicinal applications in the treatment of AE through its immunomodulatory properties.

Heat-Killed Enterococcus faecalis EF-2001 Ameliorates Atopic Dermatitis in a Murine Model.

Recent reports have shown the immunomodulatory effect of heat-killed lactic acid bacteria. Atopic dermatitis (AD) is an allergic skin disease, caused by immune dysregulation among other factors. The aim of this study was to assess the effect of heat-killed Enterococcus faecalis EF-2001 (EF-2001) on AD. We established an in vivo AD model by repeated local exposure of Dermatophagoides farinae extract (DFE; house dust mite extract) and 2,4-dinitrochlorobenzene (DNCB) to the ears of mice. After oral administration of EF-2001 for four weeks, the epidermal and dermal ear thickness, mast cell infiltration, and serum immunoglobulin levels were measured. In addition, the gene expression levels of pathogenic cytokines in the ears, lymph nodes, and splenocytes were assayed. EF-2001 attenuated AD symptoms based on the ear thickness, histopathological analysis, and serum immunoglobulin levels. Moreover, EF-2001 decreased the DFE/DNCB-induced expression of various pathogenic cytokines in the ears, lymph nodes, and splenocytes. These results suggest that EF-2001 has therapeutic potential in the treatment of AD owing to its immunomodulatory effects.

Carpesium macrocephalum attenuates lipopolysaccharide-induced inflammation in macrophages by regulating the NF-κB/IκB-α, Akt, and STAT signaling pathways.

Carpesium macrocephalum (CM) Fr. et Sav. (Compositae) has been used in Chinese folk medicine as an analgesic, hemostatic, antipyretic, and to suppress inflammatory conditions. In the present study we aimed to provide scientific evidence for the anti-inflammatory properties of CM extract and evaluate the intrinsic mechanisms involved in both in vitro and in vivo experimental models. In in vitro findings, CM significantly inhibited the LPS-stimulated release of proinflammatory mediators such as nitric oxide, tumor necrosis factor-alpha, prostaglandin E2, and interleukin-6 in RAW264.7 macrophages in a concentration-dependent fashion. The attenuation of inflammatory responses in LPS-activated RAW264.7 cells by CM was closely associated with the suppression of nuclear factor-kappa B (NF-κB) phosphorylation, IκB-α degradation, and phosphorylation of Akt. CM treatment also attenuated the phosphorylation of STAT through TRIF dependent pathways in LPS-activated RAW264.7 cells. In vivo studies revealed that CM extract concentration dependently suppressed the acetic acid-induced vascular permeability in mice. Considering the data obtained regulation of multiple signaling mechanisms involving TRIF and Akt/NF-κB pathways might be responsible for the potent anti-inflammatory action of CM, substantiating its traditional use in inflammatory diseases.

Valeriana officinalis extract and its main component, valerenic acid, ameliorate D-galactose-induced reductions in memory, cell proliferation, and neuroblast differentiation by reducing corticosterone levels and lipid peroxidation.

Valeriana officinalis is used in herbal medicine of many cultures as mild sedatives and tranquilizers. In this study, we investigated the effects of extract from valerian root extracts and its major component, valerenic acid on memory function, cell proliferation, neuroblast differentiation, serum corticosterone, and lipid peroxidation in adult and aged mice. For the aging model, D-galactose (100 mg/kg) was administered subcutaneously to 6-week-old male mice for 10 weeks. At 13 weeks of age, valerian root extracts (100 mg/kg) or valerenic acid (340 µg/kg) was administered orally to control and D-galactose-treated mice for 3 weeks. The dosage of valerenic acid (340 µg/kg), which is the active ingredient of valerian root extract, was determined by the content of valerenic acid in valerian root extract (3.401±0.066 mg/g) measured by HPLC. The administration of valerian root extract and valerenic acid significantly improved the preferential exploration of new objects in novel object recognition test and the escape latency, swimming speeds, platform crossings, and spatial preference for the target quadrant in Morris water maze test compared to the D-galactose-treated mice. Cell proliferation and neuroblast differentiation were significantly decreased, while serum corticosterone level and lipid peroxidation in hippocampus were significantly increased in the D-galactose-treated group compared to that in the control group. The administration of valerian root extract significantly ameliorated these changes in the dentate gyrus of both control and D-galactose-treated groups. In addition, valerenic acid also mitigated the D-galactose-induced reduction of these changes. These results indicate that valerian root extract and valerenic acid enhance cognitive function, promote cell proliferation and neuroblast differentiation, and reduce serum corticosterone and lipid peroxidation in aged mice.

Inhibitory effects of Acorus calamus extracts on mast cell-dependent anaphylactic reactions using mast cell and mouse model.

ETHNOPHARMACOLOGICAL RELEVANCE: Acorus calamus Linn. (Araceae) is a traditional herbal plant used for centuries to treat various allergic symptoms including asthma and bronchitis. AIM OF THE STUDY: The present study was focused to provide a pharmacological basis for the traditional use of Acorus calamus in allergic symptoms using the mast cell-dependent anaphylactic reactions in in vitro and in vivo models. MATERIALS AND METHODS: Cell viabilities were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Dinitrophenyl-human serum albumin (DNP-HSA) induced ß-hexosaminidase and interleukin (IL)-4 productions in IgE-sensitized rat basophilic leukaemia (RBL-2H3) cells were measured by enzymatic assay and enzyme-linked immunosorbent assay (ELISA). Passive cutaneous anaphylaxis (PCA) reaction mouse model was implemented for in vivo studies. RESULTS: Hot water (HW), butylene glycol (BG), hexane (HE) and steam distilled (SD) extracts of Acorus calamus showed different cytoxicity levels evaluated in RBL-2H3 cells. Sub-toxic doses of HW extract suppressed the ß-hexosaminidase secretion and IL-4 production significantly and dose dependently in DNP-HSA induced IgE-sensitized RBL-2H3 cells compared to other extracts of Acorus calamus. Further, in vivo studies also revealed that the HW extract significantly inhibited the PCA reaction in mouse compared to the normal control group. CONCLUSION: HW extract of Acorus calamus most effectively inhibited degranulation and IL-4 secretion in DNP-HSA-stimulated RBL-2H3 cells and also reduced the mast cell-mediated PCA reaction in mouse, providing a therapeutic evidence for its traditional use in ameliorating allergic reactions.

Major constituents and antimicrobial activity of Korean herb Acorus calamus.

The constituents and antimicrobial activity of the essential oil from Acorus calamus were analysed. Methyl isoeugenol and cyclohexanone were identified as the major constituents of the essential oil. The essential oil was tested for antimicrobial activity against bacteria and yeast, and has shown strong antibiotic activities against most of the tested microbes, except Escherichia coli. The hexane extract has shown a similar pattern of antimicrobial activity as the essential oil. Methyl isoeugenol, the most abundant constituent in the essential oil, has also shown similar antimicrobial activity, except against Bacillus subtilis. The essential oil as well as the hexane extract and methyl isoeugenol have shown antimicrobial activity against Propionibacterium acne, which is known to be involved in acne vulgaris.

MyD88-dependent Toll-like receptor signaling is required for murine macrophages response to IS2.

IS2, a soluble ß-glucan isolated from the cell wall of mutated Saccharomyces cerevisiae (S. cerevisiae) enhances the immune response compared to the wild type (WT) ß-glucan. In the present investigation we report that Toll-like receptor (TLR)/MyD88 signaling pathway was responsible in IS2 ß-glucan-mediated cellular response in RAW264.7 murine macrophages. Data revealed that IS2 ß-glucan significantly up-regulated the TLR2/TLR4 expression. Moreover, TLR2/TLR4 responds to IS2 resulting in murine macrophage activation. In addition, the IS2 signal led to cytokine secretions of IL-6 and TNF-α. In the case of thioglycolate-elicited peritoneal macrophages from MyD88-deficient mice, the decrease in cytokines was observed. Further the mitogen-activated protein kinases (MAPKs) phosphorylation was evident and degradation of IκB-α was increased after stimulation with IS2 ß-glucan. Further examination with MyD88-deficient mice revealed that the MyD88 pathway might play an important role for IS2 ß-glucan-mediated activation of macrophages.

A novel cellulolytic, anaerobic, and thermophilic bacterium, Moorella sp. strain F21.

A cellulolytic and thermophilic anaerobe was isolated from soil. This bacterium made a halo on a roll-tube culture containing Avicel. Analysis of the PCR-based 16S rRNA gene sequence showed that the bacterium was closely related to Moorella thermoacetica. Scanning electron microscopy showed the bacterium is a rod and has no protuberant structure on the surface of cells growing on cellulose, suggesting that this strain is a non-cellulosomal cellulolytic bacterium. Carboxymethyl cellulase and xylanase activities were detected in the culture broth. A major fermentation product from ball-milled cellulose was acetate. This strain has a potential to convert cellulosic biomass to acetate, directly.