Article

The Effect of Wasabi Rhizome Extract on Atopic Dermatitis-Like Symptoms in HR-1 Hairless Mice

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Abstract

We investigated the effect of wasabi rhizome extract on atopic dermatitis (AD) model mice. The wasabi extract was fed to the HR-1 hairless mice, which develop AD-like symptoms with a special diet (HR-AD diet). The extract was expected to reduce the symptoms induced. Wasabi rhizome-containing HR-AD diet (5% and 10%) reduced the scratching behavior, and the 10% wasabi rhizome HR-AD diet significantly reduced scratching behavior on days 28, 35 and 42. Plasma components (histamine, eotaxin, IgE and thymus and activation-regulated chemokine (TARC)) were decreased in the 10% wasabi rhizome HR-AD diet. In histopathological examinations (toluidine blue (T.B.), major basic protein (MBP), CD4, IL-4, IL-5, eotaxin, TARC and IgE), the wasabi rhizome-containing HR-AD diet (5% and 10%) significantly reduced the number of positive stained cells. These results suggested that the wasabi rhizome extract improved the AD-like symptoms of HR-1 hairless mice.

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... Stud ies have shown that Wasabi has multifarious functions such as antimicrobial, anticoagulation, antiinflammatory, anti obesity, and anticancer. [1][2][3][4][5] These activities can be attributed to a group of bioactive compounds identified as isothio cyanates (ITCs). 6 They include 4(methylsulfinyl)butyl iso thiocyanate (4MSITC, usually called sulforaphane, SFN), 6(methylsulfinyl)hexyl isothiocyanate (6MSITC), and 6(methylthio)hexyl isothiocyanate (6MTITC; Fig. 1). ...
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6-(Methylsulfinyl)hexyl isothiocyanate (6-MSITC), 6-(methylthio)hexyl isothiocyanate (6-MTITC), and 4-(methylsulfinyl)butyl isothiocyanate (4-MSITC) are isothiocyanate (ITC) bioactive compounds from Japanese Wasabi. Previous in vivo studies highlighted the neuroprotective potential of ITCs since ITCs enhance the production of antioxidant-related enzymes. Thus, in this present study, a genome-wide DNA microarray analysis was designed to profile gene expression changes in a neuron cell line, IMR-32, stimulated by these ITCs. Among these ITCs, 6-MSITC caused the expression changes of most genes (263), of which 100 genes were upregulated and 163 genes were downregulated. Gene categorization showed that most of the differentially expressed genes are involved in oxidative stress response, and pathway analysis further revealed that Nrf2-mediated oxidative stress pathway is the top of the ITC-modulated signaling pathway. Finally, real-time polymerase chain reaction (PCR) and Western blotting confirmed the gene expression and protein products of the major targets by ITCs. Taken together, Wasabi-derived ITCs might target the Nrf2-mediated oxidative stress pathway to exert neuroprotective effects.
... Wasabi leaf extract also inhibits the differentiation of preadipocytes, suggesting that the extract may be able to prevent obesity and insulin resistance (Ogawa et al., 2010). In addition, wasabi rhizome extract improved the atopic dermatitis-like symptoms of HR-1 hairless mice (Nagai and Okunishi, 2009). ...
Article
Wasabi (Wasabia japonica) is a traditional condiment used in Japanese dishes. The wasabi rhizome shows potent amylolytic activity. The amylase activities of 12 Brassicaceae vegetables, including wasabi and three non-Brassicaceae root vegetables, were determined and compared. Among the 15 vegetables, wasabi showed the highest amylase activity (203 U g-1 fresh weight). The second and third highest activities were found in horseradish (14 U g-1 fresh weight) and sweet potato (8.6 U g-1 fresh weight), respectively. The 12 other vegetables exhibited activities less than 3 U g-1 fresh weight. Immunoblot analyses using an anti-radish (Raphanus sativus) β-amylase antibody indicated that wasabi contained an abundance of the antigen. Tissue printing indicated that the β-amylase antigen is generally distributed throughout the wasabi rhizome. These results suggest that wasabi contains a large amount of β-amylase, and therefore shows strong amylolytic activity.
... 6-MSITC has been studied for its physiological function, including antiplatelet (Morimitsu et al., 2000), anticancer (Morimitsu et al., 2000;Watanabe et al., 2003), detoxifying (Morimitsu et al., 2000;Toyama et al., 2011), anti-inflammatory (Uto et al., 2005), antidiabetic (Fukuchi et al., 2004;Yoshida et al., 2011), and antiallergic activities (Nagai and Okunishi, 2009;Yamada-Kato et al., 2012). ...
Article
Wasabi is a member of the Brassicaceae family and produces various isothiocyanates (ITCs). Because 6-methylsulfinylhexyl ITC (6-MSITC) is stable among wasabi ITCs, it has potential as a functional compound. Hair loss can have psychological and social effects on an individual because of its impact on appearance. In this study, we investigated the stimulatory effects of 6-MSITC by culturing on human follicle dermal papilla cells (DPCs). Results showed that 6-MSITC significantly promoted DPC proliferation and upregulated vascular endothelial growth factor (VEGF) mRNA levels compared to control. Furthermore, 6-MSITC significantly upregulated adenosine A2b receptor (ADORA2b) mRNA levels. Previous studies have reported that VEGF was induced through ADORA1 and ADORA2 pathways. We suggest that 6-MSITC stimulates hair growth on DPCs related to the upregulation of ADORA2b mRNA level. Thus, 6-MSITC may be used as a functional compound.
... In this context, a major role is exerted by ITCs, a broad group of highly reactive compounds characterised by a common sulphur-containing functional group (-N = C = S) and a variable alkyl or allyl portion. In particular, 6-MITC, the main ITC derived from the rhizome of Wasabia japonica, has recently stimulated the interest of researchers through its proven anti-inflammatory, antioxidant and neuroprotective properties that have led to its hypothesised use as a chemopreventive agent [23,[30][31][32]. ...
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Numerous laboratory and epidemiological studies show that the risk of developing several types of cancer can be reduced with the employment of natural substances that act with multiple mechanisms. In this context, an important role is played by the isothiocyanates. Recently, 6-(methylsulfonyl)hexyl isothiocyanate (6-MITC), present in the root of Wasabia Japonica, has stimulated the interest of researchers as a chemopreventive agent. In this particular study we have focused on evaluating 6-MITC's in vitro cytotoxic, cytostatic and cytodifferentiating activities, as well as its pro-apoptotic potential. These effects were investigated by way of flow cytometric analysis of Jurkat and HL-60 cells as well as of healthy lymphocytes extracted from the blood of AVIS donors, in order to verify a potential selectivity of action. The results demonstrate that 6-MITC exerts a stronger cytotoxic effect on tumour cells than on healthy cells. The apoptosis induction exerted by 6-MITC on transformed cells is triggered by an extrinsic pathway, as demonstrated by the statistically significant increase in the percentage of cells with activated caspase-8. It was also observed that 6-MITC is able to limit tumour growth by slowing down and blocking the cell cycle of Jurkat and HL-60 cells respectively, in a dose- and time-related manner, while exerting no activity of any kind on the replication of healthy cells. Finally, by measuring the expression levels of CD-14 and CD-15, 6-MITC showed the ability to induce cytodifferentiation of HL-60 cells into macrophage and granulocytic phenotypes.
... 6-MSITC has been studied for its physiological function, including antiplatelet (Morimitsu et al., 2000), anticancer (Morimitsu et al., 2000;Watanabe et al., 2003), detoxifying (Morimitsu et al., 2000;Toyama et al., 2011), anti-inflammatory (Uto et al., 2005), antidiabetic (Fukuchi et al., 2004;Yoshida et al., 2011), and antiallergic activities (Nagai and Okunishi, 2009;Yamada-Kato et al., 2012). ...
Article
Wasabi is a plant of Japanese origin. It belongs to the Brassicaceae family and produces various isothiocyanates (ITCs). Because 6-methylsulfinylhexyl isothiocyanate (6-MSITC) is particularly stable among wasabi ITCs, it has potential as a functional compound. To clarify the antioxidative activity of 6-MSITC, we investigated its inhibitory effect on superoxide anion (O2•⁻) generation from phorbol 12-myristate 13-acetate (PMA)-stimulated differentiated HL-60 human promyelocytic leukemia cells. Our results showed that 6-MSITC inhibited O2•⁻ generation in these cells (IC50 value: 28.9 µM). 6-MSITC at 0.8, 4, and 20 µM significantly inhibited the consumption of exogenously added NADH compared with the control. On the other hand, < 263 µM 6-MSITC did not scavenge O2•⁻ in cell-free experiments. Therefore, we suggest that 6-MSITC inhibited O2•⁻ generation by decreasing an enzymatic reaction with NADPH oxidase. Thus, 6-MSITC may be useful as a functional compound.
... They are 6-methylsulfinylhexyl isothiocyanate (6-MSITC) and 6-methylthiohexyl isothiocyanate (6-MTITC). These ITCs contributed to the antimicrobial (9), antiplatelet (10), anti-inflammatory (11), and anti-obesity (12) activities. In particular, 6-MSITC mediated important inflammatory factors, by suppressing cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and cytokines (13). ...
Article
6-MSITC and 6-MTITC are sulforaphane (SFN) analogs found in Japanese Wasabi. As we reported previously, Wasabi isothiocyanates (ITCs) are activators of Nrf2-antioxidant response element pathway, and also inhibitors of pro-inflammatory cyclooxygenase-2. This study is the first to assess the global changes in transcript levels by Wasabi ITCs, comparing with SFN, in HepG2 cells. We performed comparative gene expression profiling by treating HepG2 cells with ITCs, followed by DNA microarray analyses using HG-U133 plus 2.0 oligonucleotide array. Partial array data on selected gene products were confirmed by RT-PCR and Western blotting. Ingenuity Pathway Analysis (IPA) was used to identify functional subsets of genes and biologically significant network pathways. 6-MTITC showed the highest number of differentially altered (≥2 folds) gene expression, of which 114 genes were upregulated and 75 were downregulated. IPA revealed that Nrf2-mediated pathway, together with glutamate metabolism, is the common significantly modulated pathway across treatments. Interestingly, 6-MSITC exhibited the most potent effect toward Nrf2-mediated pathway. Our data suggest that 6-MSITC could exert chemopreventive role against cancer through its underlying antioxidant activity via the activation of Nrf2-mediated subsequent induction of cytoprotective genes.
... Grated wasabi rhizome, which contains various isothiocyanates, is a popular condiment in Japan. These isothiocyanates have many physiological functions, including anti-microbial (Isshiki et al., 1992), anti-platelet (Morimitsu et al., 2000), anti-cancer, antioxidative (Morimitsu et al., 2000(Morimitsu et al., , 2002, anti-inflammatory (Uto et al., 2005), anti-diabetic (Fukuchi et al., 2004;Yoshida et al., 2011), and anti-allergic (Nagai and Okunishi, 2009;Yamada-Kato et al., 2012) activities. Furthermore, isothiocyanates are known ligands of transient receptor potential ankyrin 1 (TRPA1) (Jordt et al., 2004;Terada et al., 2015;Uchida et al., 2012). ...
Article
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Wasabi is a plant of Japanese origin belonging to the Brassicaceae family. Although the wasabi rhizome is a popular condiment in Japan, the leaf is typically discarded. For utilization of the wasabi leaf, we investigated its antiobesity effect on Wistar rats fed a high-fat diet containing wasabi leaf extract (WLE) prepared with 50% ethanol. At the experimental endpoint, WLE had significantly decreased the body weight of rats and upregulated the mRNA expression of the β3-adrenergic receptor (Adrb3) in the interscapular brown adipose tissue (BAT). WLE may have promoted lipid absorption from the dietary fat, as the fecal lipid content was considerably lower in the WLE group. These results suggest that WLE suppressed obesity in rats fed a high-fat diet, which was related to the upregulation of Adrb3 mRNA expression in the interscapular BAT without increased fecal lipid excretion. Thus, wasabi leaves may be used as a functional food material for the suppression of obesity.
... However, besides producing a unique flavour, the isothiocyanates have been linked to health benefits in a number of studies. These include the inhibition of platelet aggregation (blood clotting) (Kumagai et al. 1994), anti-cancerous and chemopreventative properties (Chen et al. 2014;Wu et al. 2015;Hsuan et al. 2016), anti-oxidant properties (Lee et al. 2008;Sekiguchi et al. 2010), anti-hypercholesterolemic properties (Lee et al. 2008), anti-allergic effects (Yamada-Kato et al. 2012), as well as reducing dermatitis-like symptoms (Nagai & Okunishi 2009). Although there are five known isothiocyanates reported to be medicinally active in wasabi, Hao et al. (2016) found that two closely related Eutrema species may possess higher concentrations when compared to the commercially cultivated W. japonica, and could provide a better source of isothiocyanates for study and medicinal use. ...
Thesis
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Wasabi (Wasabia japonica L.) is a high-value crop in British Columbia and is cultivated in greenhouses where diseases cause economic losses and insect pest issues are emerging. A review of the current literature on wasabi reveals a lack of information on wasabi pest and disease management, especially in North America. The objective of this research was to identify current diseases affecting wasabi in BC isolates from plants showing symptoms of leaf blight, leaf spot, and white blister rust were identified by molecular and morphological methods. Results revealed that Botrytis cinerea, Collectotrichum higginsianum, and Albugo candida were present. Inoculation studies showed B. cinerea was weakly pathogenic, while C. higginsianum caused lesions on wasabi and Brassica juncea, but not on alfalfa (Medicago sativa). In culture, fastest growth of C. higginsianum occurred at 25 and 30°C, and the highest conidial production occurred under continuous darkness. Isolates of A. candida from shepherd’s purse (Capsella bursa-pastoris) plants were identical to those from wasabi, suggesting a source of inoculum. Disease control in an integrated pest management system will remain an important aspect of mitigating economic losses.
... In particular, allyl isothiocyanate (AITC)-a colorless liquid with a boiling point of 148-154°C-and 6-(methylthio) hexyl isothiocyanate (MHITC) give the characteristic green tone and pungent odor to Wasabi (Wasabia japonica (Miquel) Matsumura) [112]. Wasabi extract has been used as a domestic medicine for many purposes, such as antimicrobial, deodorization and detoxification [113] treatments as well as to improve the atopic-dermatitis-like symptoms of HR-1 hairless mice [114]. One study reported that sulforaphane (4-methylsulfinyl butyl isothiocyanate)-found in broccoli sprouts with five other isothiocyanates-exhibited potent anti-helicobacter activity [115]. ...
Article
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TRPA1 has been proposed to be associated with diverse sensory allergic reactions, including thermal (cold) nociception, hearing and allergic inflammatory conditions. Some naturally occurring compounds are known to activate TRPA1 by forming a Michael addition product with a cysteine residue of TRPA1 through covalent protein modification and, in consequence, to cause allergic reactions. The anti-allergic property of TRPA1 agonists may be due to the activation and subsequent desensitization of TRPA1 expressed in sensory neurons. In this review, naturally occurring TRPA1 antagonists, such as camphor, 1,8-cineole, menthol, borneol, fenchyl alcohol and 2-methylisoborneol, and TRPA1 agonists, including thymol, carvacrol, 1'S-1'- acetoxychavicol acetate, cinnamaldehyde, α-n-hexyl cinnamic aldehyde and thymoquinone as well as isothiocyanates and sulfides are discussed.
... This staining allows observing both rodent and human connective tissues; purple colored, metachromatic staining reactive cells are observed and evaluated (Lee et al., 2006). It was previously demonstrated that decreased in numbers of mast cells might be due to efficacy of therapeutic agents (Ahn et al., 2009;Nagai & Okunishi, 2009;Li et al., 2010;Zheng et al., 2011;Li et al., 2013). As we demonstrated, PTC significantly lowered the numbers of mast cells in mice dorsal skin, suggesting its suppressing potential against AD like symptoms and providing a possibility to utilize PTN as a raw material for the development of therapeutic agents. ...
Article
In the present study, we investigated the effects of Polygonum tinctoria Niram (PTN) on atopic dermatitis (AD) in BALB/c mice induced by 2,4-dinitrochlorobenzene (DNCB). They were divided into four groups; Control, DNCB, DNCB+1%PTN (1% PTN extract) and DNCB+5%PTN (5% PTN extract), for evaluating the change of appearance of skin surface, skin hydration, thickness of epidermis and mast cell numbers during 4 weeks. PTN suppressed symptoms of AD in appearance of skin and increased skin hydration for DNCB+1%PTN and DNCB+5%PTN. Treatment with PTN significantly decreased the levels of eosinophils. In histopathological examination, DNCB+1%PTN and DNCB+5%PTN significantly reduced the thickness of epidermis and number of mast cell in dermis. These results suggested that the PTN improved symptoms of AD in BALB/c mice.
... AITC has an asthma-protective effect when administered orally to guinea pigs (28). A wasabi rhizome extract diet (including 6-MSITC without other ITCs) improves atopic dermatitis-like symptoms in HR-1 hairless mice (29). Morimitsu et al. (26) reported that 6-MSITC is absorbed into the body following its oral administration and enters the circulatory system. ...
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Wasabi is a plant of Japanese origin. It belongs to the family Brassicaceae and produces various isothiocyanates (ITCs). To clarify the type I allergies inhibited by wasabi ITCs, we investigated the inhibitory effect on chemical mediator release from dinitrophenylated bovine serum albumin (DNP-BSA)-stimulated RBL-2H3 rat basophilic leukemia cells. Allyl ITC (AITC), sec-butyl ITC (s-BuITC), and 3-butenyl ITC (3-BuITC), which have 3 or 4 carbon chains, inhibited histamine release but did not inhibit the release of leukotriene B4 (LTB4) or cysteinyl LTs (CysLTs). 4-Pentenyl ITC (4-PeITC) and 5-hexenyl ITC (5-HeITC), which have 5 or 6 carbon chains and an unsaturated bond at the end, inhibited LTB4 release but did not inhibit the release of histamine or CysLTs. 6-Methylthiohexyl ITC (6-MTITC), 6-methylsulfinylhexyl ITC (6-MSITC), and 6-methylsulfonylhexyl ITC (6-MSFITC), which have a sulfur atom inserted at the end of a 6-carbon chain, inhibited the release of histamine, LTB4, and CysLTs and the elevation in intracellular Ca(2+). These results suggest that wasabi ITCs inhibited type I allergies by inhibiting chemical mediator release and that the inhibitory effects on each chemical mediator were due to differences in the side chain structure of the wasabi ITCs.
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Skin aging is a natural, unavoidable, and complex process caused by oxidative stress. As a consequence, it leads to an increase in the activation of extracellular matrix disruption enzymes and DNA damage. The search for natural sources that inhibit these mechanisms can be a good approach to prevent skin aging. The purpose of our study was to evaluate the composition of flavonoids and phenolic acids in the extracts obtained from the flowers, roots, and leaves of Eutrema japonicum cultivated in Poland. Then, the resultant extracts were subjected to an assessment of antioxidant, anti-collagenase, anti-elastase, anti-hyaluronidase, antibacterial, and cytotoxic properties. It was demonstrated that the extract from the flowers had the highest content of flavonoid glycosides (17.15 mg/g DE). This extract showed the greatest antioxidant, anti-collagenase, anti-elastase, and anti-hyaluronidase activities compared to the other samples. Importantly, the collagenase inhibitory activity of this extract (93.34% ± 0.77%) was better than that of positive control epigallocatechin gallate (88.49% ± 0.45%). An undeniable advantage of this extract was also to possess moderate antibacterial properties and no cytotoxicity towards normal human skin fibroblasts. Our results suggest that extracts from E. japonicum flowers may be considered as a promising antiaging compound for applications in cosmetic formulations.
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While the pathomechanisms of respiratory atopy are rather well established, the role of IgE-mediated hypersensitivity in the elicitation and maintenance of eczematous skin lesions in atopic eczema is still controversial. Few diseases are characterized by an equally elevated production of IgE antibodies as atopic eczema. Many authors, however, regard this only as epiphenomenon. On the other hand, there is clearcut clinical evidence for exogenous elicitation of atopic eczema by contact with aero or food allergens. A variety of hypotheses may help to explain the participation of IgE antibodies in the induction of eczema: vasoactive mediators secreted by skin mast cells or basophils after allergen contact may produce itch, contact urticaria or a 'late-phase-reaction' with consequent eczematous skin changes further maintained by scratch responses. Recent investigations stress a possible role of Langerhans cells in the epidermis with a low affinity receptor for IgE with possible function for antigen presentation, mediator release or regulatory interactions. Certain cytokines such as interleukin-4 or gamma-interferon are able to enhance the expression of the IgE-receptor on the surface of Langerhans cells. IL-4 and gamma-interferon act synergistically in this respect on Langerhans cells, contrary to B cells. Furthermore lymphocytes may act directly via certain cytokines (e.g. histamine releasing factor, chemotactic factors etc.) on mast cells or eosinophil granulocytes in a proinflammatory sense. Eosinophils seem also to be involved in the inflammatory response in atopic eczema by releasing products such as major basic protein (MBP) or eosinophil cationic protein (ECP) which has been found to be elevated in severe atopic eczema.(ABSTRACT TRUNCATED AT 250 WORDS)
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Plasma histamine concentrations were determined using a radio-enzymatic assay in fifty-four patients suffering from atopic eczema and in thirty-nine controls (contact dermatitis, psoriasis and normal non-atopic healthy volunteers). While in none of the controls histamine levels in plasma exceeded 1 ng/ml, seventeen out of fifty-four patients with atopic eczema showed increased plasma histamine concentrations ranging between 1.2 and 5.2 ng/ml. Elevated plasma histamine levels were found mostly in patients with severe eczema and high serum IgE levels. Longitudinal studies in seven patients revealed normal plasma histamine values during clinical remission.
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Skin-associated T cells are defined by the cutaneous lymphocyte-associated antigen (CLA). In atopic dermatitis (AD), CLA+ T cells harbor allergen-reactive memory cells, spontaneously secrete TH2 cytokines, and display signs of increased in vivo activation, thus relating the subset to the central disease pathomechanisms. It is not known whether the proportion of circulating CLA+ T cells might be expanded in AD. We were therefore prompted to compare the peripheral blood lymphocyte subpopulations of patients with AD with those of control subjects. We used 3-color flow cytometry to investigate age-matched peripheral blood samples of pediatric and young adult patients with mild (n = 21) or severe (n = 15) AD, patients with allergic/atopic diseases not involving the skin (n = 9), and healthy control subjects (n = 14). We found no differences among the study groups with respect to the general proportions of T cells, CD4(+) T cells, CD8(+) T cells, B cells, NK cells, CD103(+) T cells, and CD25(+) T cells among total circulating lymphocytes. However, there were slightly more CD4(+) memory cells and clearly more HLA-DR+ T cells in patients with severe AD. Most remarkably, patients with severe AD had a significantly expanded proportion of CLA+ T cells (P =.024) and CLA+/CD4(+) T cells (P =.006) but similar proportions of CLA+/CD8(+) T cells compared with control subjects. Patients with severe AD also had distinctly more HLA-DR+/CLA+ T cells than control subjects (P =. 005). Similar alterations were seen in patients with mild AD, but these were not statistically significant. After correction for age, all differences were significant only in probands less than 10 years of age. Circulating skin-associated T cells (CLA+) show signs of subset expansion and enhanced activation in patients with AD. These alterations, compared with control values, affect CD4(+) memory T cells in particular and are prominent only in children less than 10 years of age.
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Accumulating evidence indicates that eotaxin plays an integral role in tissue recruitment of eosinophils in humans as well as in animals. To clarify which types of cells are actually important as sources of human eotaxin, we used a specific enzyme-linked immunosorbent assay (ELISA) to compare various types of hemopoietic and nonhemopoietic cells for the ability to produce eotaxin protein. Regardless of various conditioning, we failed to determine any significant eotaxin generation by peripheral leukocytes and vein endothelial cells (less than 20 pg/ml). A small amount of immunoreactive eotaxin was detected in cultures of A549 bronchial epithelial cell line cells. In contrast, dermal fibroblasts were capable of generating extremely high, and potentially biologically relevant, amounts of eotaxin protein (on the order of ng/ml). The eotaxin generation was induced by tumour necrosis factor alpha (TNF-alpha) or IL-4, and the production was drastically increased by combined use of these cytokines. Because fibroblasts are ideally situated within the interstium at the sites of allergic responses, our finding that these cells represent an important cellular source of eotaxin suggests that fibroblast-derived eotaxin may act to regulate eosinophil recruitment in a paracrine fashion.
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Deposition of eosinophil granule major basic protein (MBP) often occurs in acute and chronic lesions of atopic dermatitis, but it is not clear what the factors may be that are related to the MBP deposition in some skin lesions of the disease. The purpose of this study was to determine whether a personal or family history of respiratory atopy is related to the intensity of MBP deposition in acute lesions. We immunohistochemically stained biopsy specimens from acute, non-oozing indurated erythematous lesions of atopic dermatitis with BMK-13, a monoclonal antibody which recognizes MBP. The subjects were 40 adult patients with atopic dermatitis. Of the 40 patients, 22 had a personal history of respiratory atopy, 8 had a family history of respiratory atopy, and 10 had neither a personal nor a family history of respiratory atopy. Deposition of MBP was observed in the specimens from 24 (60%) of the 40 patients examined. Furthermore, there were great individual differences in the intensity of MBP deposition. A strong MBP deposition was often seen in specimens from patients with atopic dermatitis who had a personal or family history of respiratory atopy, but was absent in specimens from those patients with atopic dermatitis who had neither a personal nor a family history of respiratory atopy. We conclude that a strong MBP deposition seems to occur in acute lesions of those patients with atopic dermatitis who have a predisposition to respiratory atopy.
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6-Methylsulfinylhexyl isothiocyanate (MS-ITC) was isolated from wasabi (Wasabia japonica, Japanese domestic horseradish) as a potential inhibitor of human platelet aggregation in vitro through our extensive screening of vegetables and fruits. In the course of an another screening for the induction of glutathione S-transferase (GST) activity in RL34 cells, MS-ITC was inadvertently isolated from wasabi as a potential inducer of GST. MS-ITC administered to rats or mice also showed both activities in vivo. As a result from elucidation of the platelet aggregation inhibition and the GST induction mechanisms of MS-ITC, the isothiocyanate moiety of MS-ITC plays an important role for antiplatelet and anticancer activities because of its high reactivity with sulfhydryl (RSH) groups in biomolecules (GSH, cysteine residue in a certain protein, etc.).
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Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease characterized by the predominant infiltration of TH2-type cells in lesional skin. Thymus and activation-regulated chemokine (TARC/CCL17) is a chemokine that attracts CC chemokine receptor 4-positive (CCR4+) or CCR8+ cells. The purpose of this study was to investigate the participation of TARC in AD. We measured serum TARC levels in 40 patients with AD, 20 healthy control subjects, and 20 patients with psoriasis. We also examined disease activity by using SCORAD score; serum soluble E-selectin, soluble IL-2 receptor, IgE, and GM-CSF levels; and eosinophil numbers in peripheral blood, as well as correlations between TARC levels and these factors. The positivity of CCR4 of CD4+CD45RO+ cells in PBMCs was examined by using FACS analysis. Immunohistochemical staining of TARC and GM-CSF was performed in the lesional skin of patients with AD. The serum TARC levels of patients with AD were significantly higher than those of healthy control subjects and patients with psoriasis. The serum TARC levels significantly correlated with eosinophil number (r = 0.61), SCORAD score (r = 0.60), and serum soluble E-selectin levels (r = 0.58) and weakly correlated with serum soluble IL-2 receptor levels (r = 0.34) in patients with AD. The TARC levels of patients with AD decreased after the treatment in accordance with the improvement of clinical symptoms. The CCR4 positivity of CD4+CD45RO+ cells in PBMCs of patients with AD was also higher than that of healthy control subjects. Immunohistochemical staining revealed that TARC was positive in keratinocytes in the epidermis and in vascular endothelial cells, T cells, and dendritic cells in the dermis. Serum TARC levels are associated with disease activity of AD, and TARC may play an important role in the pathogenesis of AD.
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The pathogenesis of atopic dermatitis (AD) is still unknown. A recent study has shown that inducible nitric oxide synthase (iNOS) is expressed in the atopic skin lesion, suggesting the involvement of nitric oxide in the skin inflammation of AD. The purpose of the study was to examine serum nitrate (NO3) levels in relation to the disease severity in children with AD. Serum nitrate levels were assessed in relation to the skin scores in 88 patients with atopic dermatitis (AD) (aged 0.4-8 years: mean+/-SD, 2.2+/-1.9, 41 boys and 47 girls) and 12 nonatopic children (aged 0.8-4 years: mean+/-SD, 1.8+/-0.9, seven boys and five girls). Serum nitrate levels of patients with AD were significantly increased as compared to nonatopic controls and were also correlated with the disease severity. The skin scores were significantly correlated with serum nitrate levels as well as peripheral eosinophil counts. Our results indicate that nitric oxide may be involved in the pathogenesis of vasodilation and erythema in AD skin.
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T(H)2 cells and eosinophils selectively express CC chemokine receptor 4 and CCR3, respectively, and their chemokine ligands are likely to play important roles in the pathogenesis of atopic dermatitis (AD). The purpose of this study was to demonstrate the presence of thymus and activation-regulated chemokine (TARC) in platelets and its release during clotting and to evaluate the circulating levels of TARC, macrophage-derived chemokine (MDC), and eotaxin in control subjects and patients with AD. We compared plasma and serum contents of TARC, MDC, and eotaxin. We measured TARC contents in platelet lysates. We analyzed the correlation of plasma levels of TARC, MDC, and eotaxin with various clinicolaboratory parameters in patients with AD. Serum contents of TARC rapidly increased during clotting, whereas those of MDC and eotaxin increased only slightly. We demonstrated that platelets contained TARC, and its levels were dramatically elevated in patients with AD. Platelets also released TARC on stimulation with thrombin. We therefore evaluated circulating levels of these chemokines in control subjects and patients with AD by using plasma samples. Plasma TARC levels were significantly increased in patients with AD (P <.0001) and showed significant correlations with severity scoring of atopic dermatitis (SCORAD) index (r = 0.665, P <.00001), serum lactate dehydrogenese levels (r = 0.696, P =.00001), eosinophil counts (r = 0.381, P =.007), and platelet counts (r = 0.562, P <.0001). Similarly, plasma MDC levels were significantly increased in patients with AD (P <.0001) and showed significant correlations with SCORAD index (r = 0.727, P <.0001), serum lactate dehydrogenese levels (r = 0.861, P <.0001), eosinophil counts (r = 0.505, P =.005), and platelet counts (r = 0.370, P =.01). On treatment, plasma TARC and MDC levels were dramatically decreased in accordance with improved SCORAD scores (P =.0012 and P =.0007, respectively). On the other hand, plasma eotaxin levels did not show any significant increase or correlation with any of the clinical parameters in patients with AD. Platelets from patients with AD contain high levels of TARC. Thus platelets might play an important role in AD pathogenesis by releasing T(H)2-attracting TARC on activation. Furthermore, circulating levels of TARC and MDC, but not those of eotaxin, correlate well with the disease activity of AD.
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To investigate the pathological findings in conjunctiva of NC/Nga mice, which develop atopic dermatitis spontaneously, we focused our study on the density of mast cells as determined by histological methods. NC/Nga mice were divided into five groups; the 4W-group comprised four 4-week-old mice without treatment, the 10W-group comprised four 10-week-old mice without treatment, the 16W-group comprised four 16-week-old mice without treatment, the Dx group comprised three 16-week-old mice undergoing topical 0.1% dexamethasone (Dx) ointment treatment, and the FK506 group comprised three 16-week-old mice undergoing topical 0.1% FK506 ointment treatment. For the histological examination, the lids and eyeballs of the mice were removed and fixed with Carnoy's solution and thin sections were made. The Carnoy-fixed specimens were stained with toluidine blue or H&E and examined histologically. Toluidine blue-stained tissue sections were examined for the density per square millimeter of mast cells, which were identified as metachromatic cells in the conjunctival tissue and lid cutaneous tissue by light microscopy. Mast cell density in the conjunctiva was 8.6 +/- 8.2 cells/mm(2) in the 4W-group, 29.2 +/- 22.0 cells/mm(2) in the 10W-group, 41.0 +/- 21.1 cells/mm(2) in the 16W-group, 22.7 +/- 17.1 cells/mm(2) in the Dx group, and 33.6 +/- 27.7 cells/mm(2) in the FK506 group. Mast cell density increased significantly with age among the 4W-, 10W-, and 16W-groups ( P < 0.001). The mast cell density of lid cutaneous tissue was higher than the conjunctival mast cell density. Mast cell density was significantly higher in the 16W-group than in the Dx group, but not significantly higher than in the FK506 group. An increase in mast cell density with age indicates that NC/Nga mice develop atopic keratoconjunctivitis-like signs. Dexamethasone ointment has a suppressive effect on the increase in mast cell density.
Article
Expression of CCR4 ligands, such as thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC), leads to preferential influx of T-helper (Th) 2-type lymphocytes to the lesional skin in atopic dermatitis (AD). Eotaxin, like the CCR3 ligand, is an important contributor of eosinophils recruitment in the course of AD. These chemokines are assumed to play an important role in the pathomechanism of AD. In this study, the serum concentration of TARC, MDC, eotaxin and total immunoglobulin E (IgE) in AD patients and healthy people were compared. Correlation between the studied indices and activity of AD was established. Severity of AD was assessed according to the SCORAD score. The study comprised 44 healthy people and 43 patients with AD. The serum concentrations of TARC, MDC, eotaxin and IgE were measured with the use of enzyme-linked immunosorbent assay kits. The serum levels of TARC, MDC, eotaxin and IgE appeared to be significantly higher in patients with AD than in healthy people. A strong positive correlation was revealed between the levels of TARC, MDC, total IgE in serum of patients with AD and SCORAD. In contrast, no significant relationship was found for the serum eotaxin concentration and TARC, MDC, IgE or disease severity. Our findings indicate that TARC and MDC are actively involved in the pathogenesis of AD and their expression, opposite to that of eotaxin, is strongly associated with clinical picture of atopic dermatitis.
Article
Dry skin/barrier dysfunction is considered to be one of the characteristic features of atopic dermatitis (AD). When HR-1 hairless mice are fed a special diet, HR-AD, dry red skin is induced. We examined whether HR-AD-fed mouse could be used as a model for AD by showing itch-associated scratching behaviour and by analysing the immunological change. HR-1 mice were fed HR-AD from 4 weeks old. HR-AD-fed mice showed severe dry skin symptoms accompanied by a decrease in dermal water content and an increase in transepidermal water loss and prolonged scratching bout duration on day 14 or 28. These symptoms became gradually worse until day 56. Marked epidermal hyperplasia and slight increase in CD4+ cells in the skin were observed from day 28. In contrast, increases in circulating T cells and serum immunoglobulin E were seen from day 41. Other skin-infiltrating inflammatory cells, such as eosinophils and mast cells, were increased on day 56 but not on day 28. Though daily oral treatment with dexamethasone reduced the increased numbers of these cells, it did not affect the dry skin symptoms or the prolonged scratching episodes. In contrast, the development of dry skin was inhibited by feeding with 10% normal diet-containing HR-AD. The skin barrier dysfunction in HR-AD-fed mice is closely associated with the development of AD-like pruritus. Changes in the immunological parameters observed may be the consequence of skin barrier dysfunction. Our findings suggest that HR-AD-fed mouse could be used as a dry skin-based experimental model for AD.
Article
Nitric oxide (NO) and reactive nitrogen species (RNS) have been implicated in the pathogenesis of inflammatory diseases. However, the involvement of NO and RNS in atopic dermatitis (AD), a pruritic inflammatory skin diseases, is not fully understood. In this study, we investigated the contribution of NO and RNS to the development of AD-like skin lesions in NC/Nga mice, an animal model for human AD. AD-like skin lesions were observed in NC/Nga mice kept under conventional conditions but not in specific pathogen-free conditions. The expression of inducible NO synthase (iNOS) and endothelial NOS (eNOS) proteins was upregulated in the dermal lesions, and that of neuronal NOS (nNOS) was downregulated in the epidermal lesions of the skin. Although the concentrations of NO2(-) and NO3(-) were lower, protein-bound nitrotyrosine content was significantly increased in the skin lesions. Immunohistochemical localization of nitrotyrosine was observed in almost all eosinophils. These results suggest that RNS formation in eosinophils and imbalance of NO metabolism are involved in the pathogenesis of AD-like skin lesions in NC/Nga mice.
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6-(Methylsulfinyl)hexyl isothiocyanate (6-MITC) is an active ingredient of Wasabi (Wasabia japonica (Miq.) Matsumura), which is a very popular pungent spice in Japan. To clarify the cellular signaling mechanism underlying the anti-inflammatory action of 6-MITC, we investigated the effects of 6-MITC on the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-activated murine macrophage RAW264 cells. 6-MITC showed a dose-dependent inhibition of LPS-induced nitric oxide (NO), iNOS mRNA and protein. LPS caused the c-Jun phosphorylation (a major component of AP-1) and IkappaB-alpha degradation. 6-MITC suppressed LPS-induced c-Jun phosphorylation, but did not inhibit IkappaB-alpha degradation. Cellular signaling analysis using MAPK-(U0126 for MEK1/2, SB203580 for p38 kinase and SP600125 for JNK) and Jak2-specific (AG490) inhibitors demonstrated that LPS stimulated iNOS expression via activating Jak2-mediated JNK, but not ERK and p38, pathway. 6-MITC suppressed iNOS expression through the inhibition of Jak2-mediated JNK signaling cascade with the attendant to AP-1 activation. In addition, the structure-activity study revealed that the inhibitory potency of methylsulfinyl isothiocyanates (MITCs) depended on the methyl chain length. These findings provide the molecular basis for the first time that 6-MITC is an effective agent to attenuate iNOS production.
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6-(Methylsulfinyl)hexyl isothiocyanate (6-MITC) is a chemopreventive compound occurring in Wasabi (Wasabia japonica (Miq.) Matsumura), which is a very popular pungent spice in Japan. We investigated the effects of 6-MITC on the expression of cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-activated murine macrophage RAW264 cells. Treatment with 6-MITC suppressed LPS-mediated induction of COX-2 protein in a dose-dependent manner. Transfections with various COX-2 promoter reporter constructs revealed that the inhibitory effects of 6-MITC on COX-2 gene expression were directed by the core promoter elements including nuclear factor kappaB (NF-kappaB), CCAAT/enhancer-binding protein (C/EBP) and cyclic AMP-response element (CRE) sites. Western blotting analysis showed that 6-MITC inhibited LPS-induced activation of MAPK (ERK, p38 kinase and JNK) and transcriptional factors (CREB, c-Jun and C/EBPdelta) binding the core elements of COX-2 promoter, substantiating the involvement of these signal transduction pathways in the regulation of COX-2 expression by 6-MITC. Moreover, Western blotting experiments with MAPK-specific inhibitors (U0126 for MEK1/2, SB203580 for p38 kinase and SP600125 for JNK) demonstrated that 6-MITC suppressed LPS-induced COX-2 expression by blocking the activation of JNK-mediated AP-1 and ERK/p38 kinase-mediated CREB or C/EBPdelta. Finally, the structure-activity study revealed that the inhibitory potency of methylsulfinyl isothiocyanates (MITCs) depended on the methyl chain length. These findings demonstrate for the first time that 6-MITC is an effective agent to attenuate COX-2 production, and enhance our understanding of the anti-inflammation properties of 6-MITC.