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.

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.

Effects of grape seed extract and its ethylacetate/ethanol fraction on blood glucose levels in a model of type 2 diabetes.

The present study observed the effects of grape seed extract (GSE) and its ethylacetate (E) and ethylacetate/ethanol (EE) fractions on blood glucose levels in C57BL/KsJ-lepr(db)/lepr(db) (db/db) mice at 4-12 weeks of age. In the GSE- and EE fraction-treated db/db group, the blood glucose concentration began to be lower than that in the vehicle-treated db/db group at 6 weeks after treatment, while the blood glucose concentration in the E fraction-treated db/db group was similar to that in the vehicle-treated db/db group. The glycosylated hemoglobin (HbA1c) level in the vehicle-treated db/db groups was 9.3%, whereas HbA1c levels in the GSE- and EE fraction-treated db/db group decreased significantly to 5.7% and 6.1%, respectively, at 8 weeks after treatment. However, administration of GSE and its EE fraction did not show any significant effects on body weights and food consumption in db/db mice. These results suggest that GSE and its EE fraction have a potential to decrease the blood glucose and HbA1c level, which is applicable to good healthy foods for reducing blood glucose levels.

Anti-tumor metastatic activity of beta-glucan purified from mutated Saccharomyces cerevisiae.

The beta-glucans isolated from Saccharomyces cerevisiae (S. cerevisiae) enhance the innate immune system, but there is little evidence for its antitumor activity. To examine the antitumor and immunostimulating activities of beta-glucan (IS-2) purified from mutated S. cerevisiae, we made an experiment on innate immune response against metastasis of cancer cells by comparing with the beta-glucan from wild-type S. cerevisiae. In experimental lung metastasis of colon 26-M3.1 carcinoma or B16-BL6 melanoma cells, prophylactic administration of beta-glucan purified from mutated S. cerevisiae significantly inhibited lung metastasis in a dose-dependent manner. Furthermore, therapeutic administration of IS-2 also significantly inhibited the colon 26-M3.1 cell growth in mice. In an assay of liver and spleen metastasis produced by i.v. inoculation of L5178Y-ML25 lymphoma cells, IS-2 also significantly inhibited metastasis in CDF1 mice. Furthermore, pretreatment with IS-2 two days before tumor inoculation significantly prolonged the survival time of tumor-bearing mice. In an in vitro cytotoxicity analysis, IS-2 (up to 100 microg/ml) did not affect the growth of colon 26-M3.1 cells. In contrast, IS-2 enhanced splenocyte proliferating activity in a dose-dependent manner. Peritoneal macrophages stimulated with IS-2 produced various cytokines, such as IL-1beta, IFN-gamma, and IL-12. In addition, treatment with IS-2 (20 microg/mouse) induced tumoricidal activity of peritoneal macrophages against colon 26-M3.1 cells. In an assay for natural killer (NK) cell activity, IS-2 (20 microg/mouse, i.v.) significantly augmented NK cytotoxicity against Yac-1 tumor cells at 2 days after IS-2 treatment. The depletion of NK cells by injection of rabbit anti-asialo GM1 serum abolished the inhibitory effect of IS-2 on lung metastasis of colon 26-M3.1 cells. These data suggest that IS-2 inhibits tumor metastasis via activation of macrophages and NK cells.

Parvalbumin immunoreactivity and protein content alter in the hippocampus after adrenalectomy in seizure sensitive gerbils.

OBJECTIVES: Neurons containing parvalbumin (PV), a calcium-binding protein, in the hippocampus, play an important role in hippocampal excitability in epilepsy. In this study, we examined temporal and spatial changes of PV immunoreactivity and protein content in the hippocampus after adrenalectomy (ADX) in seizure sensitive (SS) gerbils, which are hereditarily seizure-prone. METHODS: PV distribution and change in SS gerbils after ADX were examined in the hippocampal CA1 region and in the dentate gyrus (DG) using immunohistochemistry and Western blot analysis. RESULTS: PV immunoreactivity in sham-operated SS gerbils was detected in many CA1 pyramidal cells. Three hours after ADX, PV immunoreactivity significantly decreased in CA1 pyramidal cells and thereafter PV immunoreactivity began to increase by 4 days after ADX. Four days after ADX, PV immunoreactivity was significantly higher than that in the sham-operated SS gerbils. In the DG of sham-operated SS gerbils, PV immunoreactivity was mainly detected in polymorphic cells. Three hours after ADX, PV immunoreactivity in the DG significantly decreased in the polymorphic layer. Thereafter, PV-immunoreactive neurons decreased with time after ADX. Western blot analysis showed that change in PV protein content was similar to immunohistochemical data after ADX in SS gerbils. CONCLUSION: Our results indicate that PV is changed in hippocampus after ADX and PV may be associated with the regulation of seizure activity.

Coenzyme Q_{10} effects on manganese superoxide dismutase and glutathione peroxidase in the hairless mouse skin induced by ultraviolet B irradiation.

Coenzyme Q_{10} (CoQ_{10}) is a naturally occurring antioxidant and a prominent component of mitochondrial electron transport chain. In the present study, we investigated the effect of CoQ_{10} nanoparticle against photoaging using immunohistochemistry and Western blot analysis in the hairless mouse skin induced by ultraviolet B (UVB) irradiation (300 mJ/cm;{2}, 3 min/day for 21 days). In the UVB-irradiated distilled water (DW)-treated group, manganese superoxide dismutase (SOD2) and glutathione peroxidase (GPx) immunoreactivity and their protein levels in the skin were significantly lower than those in the control group. However, SOD2 and GPx immunoreactivity and their protein levels in the skin of the UVB-irradiated CoQ_{10}-treated group were higher than those in the UVB-irradiated DW-treated group. GPx activity in the skin in the UVB-irradiated DW-treated group significantly decreased compared to that in the control group; whereas GPx activity in the UVB-irradiated CoQ_{10}-treated group was similar to that in the control group. These results suggest that CoQ_{10} strongly inhibits oxidative stress in the skin induced by UVB via increasing SOD2 and GPx.

Neuroprotective effects of roasted licorice, not raw form, on neuronal injury in gerbil hippocampus after transient forebrain ischemia.

AIM: To observe neuroprotective effects of raw and roasted licorice against hypoxia and ischemic damage. METHODS: When elucidating the protective effects of raw and roasted licorice, we analyzed the lactate dehydrogenase (LDH) release using PC12 cells after hypoxia in an in vitro study and after transient forebrain ischemia in an in vivo study on Mongolian gerbils. RESULTS: Raw and roasted licorice significantly reduced LDH release from PC12 cells exposed to an hypoxic chamber for 1 h. In the roasted licorice-treated group, the decrease of LDH release was more pronounced compared to that of the raw licorice-treated group. In roasted licorice-treated animals, approximately 66%-71% of CA1 pyramidal cells in the ischemic hippocampus were stained with cresyl violet compared to the control group. However, in the raw licorice-treated animals, no significant neuroprotection against ischemic damage was shown. In addition, ischemic animals in roasted licorice-treated group maintained the Cu, Zn-superoxide dismutase (SOD1) activity and protein levels compared to the control group, while in raw licorice-treated group SOD1 activity and protein levels were reduced significantly. High pressure liquid chromatography analysis showed that non-polar compounds containing glycyrrhizin-degraded products, such as glycyrrhetinic acid (GA) and glycyrrhetinic acid monoglucuronide (GM), were increased in roasted licorice. CONCLUSION: Roasted licorice had neuroprotective effects against ischemic damage by maintaining the SOD1 levels. In addition, the difference in protective ability between raw and roasted licorice may be associated with non-polar compounds, such as GA and GM.

Hypoxia activates the cyclin D1 promoter via the Jak2/STAT5b pathway in breast cancer cells.

Hypoxia, a common consequence of solid tumor growth in breast cancer or other cancers, serves to propagate a cascade of molecular pathways which include angiogenesis, glycolysis, and various cell-cycle control proteins. As we have shown previously, hypoxia activates STAT5 (signal transducer and activator of transcription 5) and increases its binding activity to the GAS element in mammary epithelial cells. In this study we attempted to elucidate the mechanism by which cyclin D1 is regulated by the STAT5 protein under hypoxic conditions. Our data demonstrate that hypoxia (2% O(2)) or desferrioxamine (DFO) induces tyrosine and serine phosphorylation of STAT5 in human breast cancer cells (MCF-7) and mammary epithelial cells (HC11). Imunoprecipitation and subsequent Western analysis showed that Jak2 leads to the tyrosine phosphorylation and activation of STAT5a or STAT5b under hypoxic conditions. Using a transfected COS-7 cell model system, we demonstrate that the activity of a cyclin D1 promoter-luciferase construct increased under hypoxic conditions or DFO treatment. The activity of the STAT5b/cyclin D1 promoter increased significantly by 12 h of hypoxia, whereas the activity of the STAT5a/cyclin D1 promoter was unaffected under hypoxic conditions. These increases in promoter activity are predominantly mediated by the Jak2/STAT5b signaling pathway. We have shown by EMSA that hypoxia induces STAT5 to bind to the cyclin D1 promoter (GAS-1) in MCF-7 and HC11 cells. These data suggest that STAT5b may mediate the transcriptional activation of cyclin D1 after hypoxic stimulation.

Seizure-induced changes of mineralocorticoid and glucocorticoid receptors in the hippocampus in seizure sensitive gerbils.

Abnormal corticosteroid hormone levels during stress and resultant mineralocorticoid receptor (MR)/glucocorticoid receptor (GR) imbalance enhance the vulnerability of specific hippocampal neurons. In the present study, we investigated the distribution of MR and GR in seizure resistant (SR) and seizure sensitive (SS) gerbils, and observed the seizure-induced changes of MR and GR in the hippocampus of SS gerbils using immunohistochemistry and western blot analysis. MR and GR immunoreactivities were higher in the SS pre-seizure gerbils than that in SR gerbils. In the SR gerbils, the immunodensity of GR was high compared to that of MR. The changes of MR and GR immunoreactivities were significant in the stratum pyramidale of the hippocampal CA1 region and the infrablade of the dentate gyrus after seizure on-set. MR immunoreactivity in the CA1 region was significantly increased at 12h after seizure on-set, thereafter MR immunoreactivity was decreased. MR immunoreactivity in the dentate gyrus was decreased time-dependently after seizure on-set. GR immunoreactivity was decreased in the CA1 region and dentate gyrus time-dependently after seizure on-set. At 12h after seizure on-set, differences in MR and GR immunodensity diminished in the CA1 region and dentate gyrus. This imbalance of MR and GR immunoreactivity in these regions may be associated with seizure generation in the Mongolian gerbil, which is a hereditary seizure model.