Dietary supplementation with fructooligosaccharides attenuates allergic peritonitis in mice.

Fructooligosaccharides (FOS) are a prebiotic supplement, which can enhance immunological responses in the host to activate mucosal immunity probably through regulation of gastrointestinal microflora. Nonetheless, the therapeutic potential of prebiotics on allergic pathologies has not been fully elucidated. Therefore, the purpose of this study was to evaluate the preventive and therapeutic effects of dietary supplementation with FOS on a murine model of allergic peritonitis induced by ovalbumin (OVA). Male C3H/HeN mice were intraperitoneally administrated with OVA (1 µg) bi-weekly (Day 0-42, total four times) and were fed a diet containing 0 or 2.5% FOS ad libitum (Day 7-43). At Day 43, mice were killed and several parameters were evaluated. As results, supplementation with FOS alleviated OVA-related peritoneal inflammation characterized by trafficking of polymorphonuclear leukocytes such as eosinophils and neutrophils in the peritoneal cavity. Also, FOS significantly suppressed the protein level of interleukin (IL)-5 and eotaxin in the peritoneal lavage fluid elicited by OVA. In addition, a FOS-supplemented diet significantly reduced the serum allergen specific-IgG(1) level, whereas it significantly increased total IgA levels in the cecal contents as compared with a control diet in the presence of OVA. These results suggest that dietary supplementation with FOS can prevent/ameliorate allergic peritoneal inflammation induced by OVA. The efficacy can at least partially be associated with the regulation of Ig class switching and inhibition of the local expression of IL-5 and eotaxin.

Airborne Asian sand dust enhances murine lung eosinophilia.

There is no experimental study demonstrating the effects of airborne Asian sand dust (AASD) on allergic lung eosinophilia. The organic substances adsorbed onto AASD collected from the atmosphere of Iki-island in Japan were excluded by heat treatment at 360°C for 30 min. The effects of AASD or heated-AASD (H-AASD) towards allergic lung inflammation were compared in murine lungs to investigate the role of organic substances. ICR mice were administrated with the two kinds of AASD and/or ovalbumin (OVA) intratracheally four times at 2-week intervals. AASD and H-AASD enhanced eosinophil recruitment induced by OVA in the alveoli and in the submucosa of the airway, which has a goblet cell proliferation in the bronchial epithelium. AASD and H-AASD synergistically increased Th2 cytokines-interleukin-13 (IL-13), eosinophil-relevant cytokine and chemokine, such as IL-5, and monocyte chemotactic protein-3 (MCP-3) induced by OVA in whole lung lavage fluid. The enhancing effects were much greater in AASD than in H-AASD. AASD induced adjuvant effects on OVA-specific immunoglobulin E (IgE) and IgG1 production. In an in vitro study using RAW264.7 cells, AASD increased the expression of Toll-like receptors 2 (TLR2) mRNA, but not TLR4 mRNA. AASD increased mRNA expression of NALP3, ASC, and IL-1ß compared with the control. H-AASD caused no expression of either mRNA. These results suggest that the aggravated lung eosinophilia in AASD is due to activation of a Th2-associated immune response and that the activation of TLR2 and NALP3 inflammasome by microbial materials could be participating in this phenomenon.

Urban particulate matter in Beijing, China, enhances allergen-induced murine lung eosinophilia.

It has been reported that ambient particulate matter (PM) in some large cities, such as Beijing, China, causes adverse respiratory health effects. However, there is currently no experimental report on the relationship between bronchial asthma and urban PM (UPM) in northeast Asia. In this study, the microbial and chemical substances adsorbed onto UPM collected in Beijing were excluded by heat-treatment at 360 degrees C for 30 min. The effects of UPM or heated UPM (H-UPM) toward allergic lung inflammation were compared in murine lungs to investigate the role of organic substances. ICR mice were administrated intratracheally with the two kinds of UPM and/or ovalbumin (OVA) 4 times at 2-week intervals. UPM and H-UPM enhanced eosinophil recruitment induced by OVA in the alveoli and in the submucosa of the airway, which has a goblet cell proliferation in the bronchial epithelium. UPM and H-UPM synergistically increased Th-2 cytokines--interleukin (IL)-4 and IL-13, eosinophil-relevant cytokines and chemokines, such as IL-5 and monocyte chemotactic protein-3 (MCP-3), induced by OVA in bronchoalveolar lavage fluid (BALF). The enhancing effects were much greater in UPM than in H-UPM. UPM induced adjuvant effects on specific immunoglobulin E (IgE) and IgG1 production by OVA. In an in vitro study using RAW264.7 cells, UPM increased the expression of Toll-like receptor 2 (TLR2) mRNA, but not TLR4 mRNA. H-UPM caused no expression of both TLR mRNAs. These results suggest that the aggravated lung eosinophilia in UPM was due to activation of a Th2-associated immune response via the activation of TLR2 by microbial materials. Chemical materials of air pollutant origin contained in UPM, and inorganic components (elemental carbon, mineral elements) in H-UPM, could also cause the aggravation.

Peroxiredoxin I is a negative regulator of Th2-dominant allergic asthma.

Peroxiredoxin (Prx) I, a ubiquitous antioxidant enzyme, is known to protect against inflammation; however, its role in the allergic inflammation remains unidentified. We determined whether intristic Prx I protects against allergic asthma traits using Prx-I knockout (-/-) mice. Prx I (-/-) and wild-type (WT) mice were immunized with ovalbumin (OVA) plus aluminum potassium sulfate (Alum: Th2 adjuvant) and subsequently challenged with OVA. Twenty-four hours after the last OVA challenge, leukocyte influx including eosinophils into bronchoalveolar lavage fluid was significantly greater in Prx I (-/-) mice compared to that in WT mice. On the other hand, when these mice were immunized with OVA+complete Freund's adjuvant (Th1 adjuvant), opposite phenomenon was observed. In the presence of OVA/Alum, peribronchial inflammatory leukocyte infiltration, cholinergic airway resistance, and the lung expression of interleukin (IL)-2 were significantly greater and that of interferon-gamma was significantly lesser in Prx I (-/-) than in WT mice. In vitro, OVA/Alum-sensitized Prx I (-/-) T cells proliferated more profoundly than WT T cells when they were cocultured with syngeneic bone marrow-generated dendritic cells. These results indicate that endogenous Prx I protects against allergen-related Th2-type airway inflammation and hyperresponsiveness, at least partly, via the suppression of the lung expression of IL-2 and regulation of the Th1/Th2 balance in addition to its antioxidative properties. Furthermore, Prx I can inhibit allergen-specific T-cell proliferation through immunological synapse. Our findings implicate an alternative therapeutic value of Prx I in the treatment of Th2-skewed allergic airway inflammatory diseases such as atopic asthma.

Dietary supplementation with cacao liquor proanthocyanidins prevents elevation of blood glucose levels in diabetic obese mice.

OBJECTIVE: Effective approaches should be established to prevent the onset of type 2 diabetes mellitus, which has been increasing in developed countries. The present study examined whether dietary supplementation with cacao liquor proanthocyanidins (CLPr) could prevent elevation of blood glucose levels in mice with diabetes mellitus and obesity. METHODS: C57BL/KsJ-db/db (db/db) diabetic obese mice and C57BL/KsJ-db/+m (db/+m) control mice were fed a diet containing 0% w/w CLPr (0% CLPr), 0.5% w/w CLPr (0.5% CLPr), or 1.0% w/w CLPr (1.0% CLPr) from age 3 wk to age 6 wk. Levels of blood glucose were measured at 4 and 5 wk of age. The animals were sacrificed and the levels of blood glucose and fructosamine were measured at 6 wk of age. RESULTS: The levels of blood glucose and fructosamine were higher in the db/db mice than in the db/+m mice fed a diet containing 0%, 0.5%, or 1.0% CLPr. In the db/+m mice, the levels of blood glucose or fructosamine were not significantly different across animals fed 0% CLPr, 0.5% CLPr, and 1.0% CLPr. In the db/db mice, however, a diet containing 0.5% or 1.0% CLPr decreased the levels of blood glucose and fructosamine compared with that containing 0% CLPr without significant effects on body weights or food consumption. CONCLUSION: Dietary supplementation with CLPr can dose-dependently prevent the development of hyperglycemia in diabetic obese mice. The dietary intake of food or drinks produced from cacao beans might be beneficial in preventing the onset of type 2 diabetes mellitus.

Suppression of Th1 and Th2 immune responses in mice by Sinomenine, an alkaloid extracted from the chinese medicinal plant Sinomenium acutum.

The present study was designed to investigate the effect of sinomenine (SIN), an alkaloid extracted from Sinomenium acutum, on Th1 and Th2 immune responses in mice. For this investigation, mice were S. C. immunized with ovalbumin (OVA) emulsified with complete Freund's adjuvant (day 0). Varying doses of SIN were orally administered daily over a period of 21 days, commencing on day 0. On day 21, anti-OVA IgG and proliferative responses of spleen cells to the antigen were measured. Anti-OVA IgG2a and IFN-gamma were measured as indicators of Th1 immune responses and anti-OVA IgG1, IgE, and IL-5 as those of Th2 responses. TGF-beta was measured as an indicator of Th3 immune responses. The results showed that treatment with SIN was followed by decreases in anti-OVA IgG and the antigen-specific splenocyte proliferation. Production of all isotypes of antibodies including anti-OVA IgG2a, IgG1 and IgE as well as secretion of cytokines such as IFN-gamma and IL-5 was suppressed by SIN, although the suppression of anti-OVA IgG2a and IFN-gamma by the alkaloid appeared to be greater than that of anti-OVA IgG1, IgE, and IL-5. In addition, SIN enhanced the secretion of TGF-beta. These results suggest that SIN appears to have suppressive effects on both Th1 and Th2 immune responses. The results also suggest that Th1 responses may be more preferentially suppressed by the Sinomenium acutum-derived alkaloid compared to Th2 responses. TGF-beta may at least in part contribute to the suppression of Th1 as well as Th2 immune responses.

Effects of volatile constituents of rosemary extract on lung inflammation induced by diesel exhaust particles.

Epidemiological and experimental studies have implicated that diesel exhaust particles are involved in increases in morbidity and mortality from lung diseases. Recently, we have demonstrated that rosmarinic acid, a polyphenolic liquid component in perilla, inhibits lung inflammation induced by diesel exhaust particles in vivo, partly through its antioxidative property. We have also shown the antioxidative activities of volatile constituents of rosemary extract, the gaseous component in perilla, in vitro. The purpose of this study was to evaluate the effects of intratracheal administration of volatile rosemary extract on lung inflammation induced by diesel exhaust particles. ICR mice were treated with intratracheal administration of volatile rosemary extract before intratracheal exposure to diesel exhaust particles. Twenty-four hr later, diesel exhaust particles exposure elicited lung inflammation characterized by the infiltration of neutrophils and eosinophils, which was confirmed by cellular profile of bronchoalveolar lavage fluid and histological examination. Diesel exhaust particles enhanced the protein expressions of interleukin-1beta, macrophage inflammatory protein-1alpha, macrophage chemoattractant protein-1, and keratinocyte chemoattractant in the lung. Pretreatment with rosemary extract significantly inhibited the diesel exhaust particles-induced lung inflammation. Rosemary extract treatment also suppressed the diesel exhaust particles-enhanced lung expression of macrophage inflammatory protein-1alpha, macrophage chemoattractant protein-1, and keratinocyte chemoattractant. These results suggest that intratracheal administration of rosemary extract can prevent lung inflammation induced by diesel exhaust particles. The preventive effect is mediated, at least partly, through the inhibition of the enhanced lung expressions of macrophage inflammatory protein-1alpha, macrophage chemoattractant protein-1, and keratinocyte chemoattractants.

Effects of volatile constituents of a rosemary extract on allergic airway inflammation related to house dust mite allergen in mice.

Perilla leaf extract is known to have anti-inflammatory properties. Recently, we have demonstrated that rosmarinic acid, a polyphenolic liquid component in perilla, inhibits the allergic airway inflammation induced by house dust mites (HDMs) in vivo. The purpose of this study was to evaluate the effects of intratracheal (i.t.) exposure to volatile constituents of a rosemary extract (VR), gaseous components in perilla, on a murine model of allergic asthma induced by HDM. C3H/HeN mice were treated 7 times weekly with i.t. exposure. The HDM allergen challenge elicited a pulmonary eosinophilic inflammation accompanied by an increase in the lung expression of interleukin (IL)-5, IL-13, and eotaxin. VR inhibited increases in the number of eosinophils, neutrophils, and mononuclear cells around the airways and those in the bronchoalveolar lavage fluid. VR exposure also significantly suppressed the expression of IL-13 enhanced by HDM allergen. These results suggest that i.t. exposure to VR can, at least partially, prevent allergic airway inflammation induced by HDM. The preventive effect is associated with inhibition of the enhanced local expression of IL-13.

Complementary DNA microarray analysis in acute lung injury induced by lipopolysaccharide and diesel exhaust particles.

We have recently shown that diesel exhaust particles (DEP) synergistically enhance acute lung injury related to lipopoly-saccharide (LPS) in mice. The present study used cDNA microarray to elucidate the effects of DEP on the global pattern of LPS-related gene expression in the murine lung. The number of genes upregulated >/=2-fold as compared with their expression levels in the vehicle group was greater in the LPS group than in other groups, but treatment with DEP and LPS dramatically increased the number of the genes upregulated >/=6-fold. In particular, gene expression of metallothionein-1 and -2, S100 calcium-binding protein A9, lipocalin 2, and small inducible cytokine B family member 10 was higher by >/=20-fold in the DEP + LPS group than in the vehicle group. These results were concomitant with those obtained by real-time reverse transcription-polymerase chain reaction analysis in the overall trend. Our findings suggest that intense, focused expression of genes such as S100 calcium-binding protein A9, lipocalin 2, and small inducible cytokine B family member 10 relates to the synergistic aggravation of acute lung injury by LPS and DEP rather than weak, broad expression of various genes by exposure of LPS alone.

A novel water-soluble vitamin E derivative prevents acute lung injury by bacterial endotoxin.

1. Various chemokines, such as keratinocyte chemoattractant (KC), macrophage inflammatory protein (MIP)-1alpha and macrophage chemoattractant protein (MCP)-1, are involved in the pathogenesis of acute lung injury induced by bacterial endotoxin (lipopolysaccharide; LPS). Oxidative stress is an important regulator of the expression of these chemokines, whereas vitamin E protects against LPS-induced insults. In the present study, we determined the effects of 2-(alpha-D-glucopyranosyl) methyl-2,5,7,8-tetramethylchroman-6-ol (TMG), a novel water-soluble vitamin E derivative with excellent anti-oxidant activity, on acute lung injury induced by intratracheal instillation of LPS (125 micro g/kg) in mice. 2. When TMG was administered intratracheally and intravenously (0.1, 1.0 or 10 mg/kg), it dose-dependently decreased the infiltration of neutrophils into bronchoalveolar lavage fluid after LPS challenge. 3. Histological examination showed that treatment with TMG ameliorated the LPS-induced infiltration of neutrophils into the lungs. Furthermore, TMG attenuated the LPS-induced increase in pulmonary expression of KC, MIP-1alpha and MCP-1 at both the transcriptional and translational levels. 4. These results indicate that TMG is a possible treatment for acute lung injury, especially that caused by Gram-negative bacteria. The therapeutic effect of TMG may be mediated, at least in part, by suppression of the local expression of chemokines, possibly through its strong anti-oxidant activity.

Extract of Perilla frutescens enriched for rosmarinic acid, a polyphenolic phytochemical, inhibits seasonal allergic rhinoconjunctivitis in humans.

Extract of Perilla frutescens enriched for rosmarinic acid, a polyphenolic phytochemical, suppresses allergic immunoglobulin responses and inflammation caused by polymorphonuclear leukocytes (PMNL) in mice. However, few placebo-controlled clinical trials have examined the efficacy and safety of polyphenolic phytochemicals for treatment of allergic inflammatory diseases in humans. The present study determined whether oral supplementation with rosmarinic acid is an effective intervention for patients with seasonal allergic rhinoconjunctivitis (SAR). In this 21-day, randomized, double-blind, age-matched, placebo-controlled parallel group study, patients with mild SAR were treated daily with extract of Perilla frutescens enriched for rosmarinic acid (200 mg [n=10] or 50 mg [n=9]) or placebo (n=10). Patients recorded symptoms daily in a diary. Profiles of infiltrating cells and concentrations of eotaxin, IL-1beta, IL-8, and histamine were measured in nasal lavage fluid. Serum IgE concentrations and routine blood tests were also examined. As compared with placebo supplementation, supplementation with extract of Perilla frutescens enriched for rosmarinic acid resulted in a significant increase in responder rates for itchy nose, watery eyes, itchy eyes, and total symptoms (P<0.05). Active treatment significantly decreased the numbers of neutrophils and eosinophils in nasal lavage fluid (P<0.05 vs. placebo). Patients reported no adverse events, and no significant abnormalities were detected in routine blood tests. In conclusion, extract of Perilla frutescens enriched for rosmarinic acid can be an effective intervention for mild SAR at least partly through inhibition of PMNL infiltration into the nostrils. Use of this alternative treatment for SAR might reduce treatment costs for allergic diseases.

Anti-inflammatory and anti-allergic effect of rosmarinic acid (RA); inhibition of seasonal allergic rhinoconjunctivitis (SAR) and its mechanism.

The present study was undertaken to determine whether oral supplementation with rosmarinic acid (RA) is an effective intervention for patients with SAR. In addition, the anti-inflammatory mechanism of RA also estimated in the ear edema models. CLINICAL TRIAL: Patients were treated daily with RA (200 mg or 50 mg) or placebo for 21 days. Patients recorded symptoms daily and profiles of infiltrating cells and concentration of cytokines were measured in nasal lavage fluid. Compared to placebo, supplementation with RA resulted in a significant decrease in responder rates for each symptom. RA also significantly decreased the numbers of neutrophils and eosinophils in nasal lavage fluid. ANIMAL STUDY: Topical application RA showed anti-inflammatory activity 5-hours after 12-tetradecanoylphorbol 13-acetate (TPA) treatment with marked inhibition of neutrophil infiltration. Up regulation of ICAM-1, VCAM-1 cyclooxygenase-2 (COX-2), KC and MIP-2 by TPA were markedly reduced by pre-treatment with extract of perilla (PE) or RA. Reactive oxygen radical production detected as thiobarbituric acid reactive substance (TBARS), lipid peroxide (LPO) and 8-hydroxy-2'deoxyguanosine (8OH-dG), by double treatment of TPA was reduced by pretreatment with PE or RA. RA is an effective intervention for SAR that is mediated by inhibition of PMNL infiltration. This effect of RA is due to two independent mechanisms: inhibition of the inflammatory response and scavenging of ROS.

Rosmarinic acid inhibits lung injury induced by diesel exhaust particles.

Epidemiological and experimental studies have suggested that diesel exhaust particles (DEP) may be involved in recent increases in lung diseases. DEP has been shown to generate reactive oxygen species. Intratracheal instillation of DEP induces lung inflammation and edema in mice. Rosmarinic acid is a naturally occurring polyphenol with antioxidative and anti-inflammatory activities. We investigated the effects of rosmarinic acid on lung injury induced by intratracheal administration of DEP (500 microg/body) in mice. Oral supplementation with administration of rosmarinic acid (2 mg/body for 3 d) inhibited DEP-induced lung injury, which was characterized by neutrophil sequestration and interstitial edema. DEP enhanced the lung expression of keratinocyte chemoattractant (KC), interleukin-1beta, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1alpha, which was inhibited by treatment with rosmarinic acid. DEP enhanced expression of iNOS mRNA and formation of nitrotyrosine and 8-OHdG in the lung, which was also inhibited by rosmarinic acid. These results suggest that rosmarinic acid inhibits DEP-induced lung injury by the reduction of proinflammatory molecule expression. Antioxidative activities of rosmarinic acid may also contribute to its protective effects.