Cycloastragenol alleviates airway inflammation in asthmatic mice by inhibiting autophagy.

Cycloastragenol (CAG), a secondary metabolite from the roots of Astragalus zahlbruckneri, has been reported to exert anti­inflammatory effects in heart, skin and liver diseases. However, its role in asthma remains unclear. The present study aimed to investigate the effect of CAG on airway inflammation in an ovalbumin (OVA)­induced mouse asthma model. The current study evaluated the lung function and levels of inflammation and autophagy via measurement of airway hyperresponsiveness (AHR), lung histology examination, inflammatory cytokine measurement and western blotting, amongst other techniques. The results demonstrated that CAG attenuated OVA­induced AHR in vivo. In addition, the total number of leukocytes and eosinophils, as well as the secretion of inflammatory cytokines, including interleukin (IL)­5, IL­13 and immunoglobulin E were diminished in bronchoalveolar lavage fluid of the OVA­induced murine asthma model. Histological analysis revealed that CAG suppressed inflammatory cell infiltration and goblet cell secretion. Notably, based on molecular docking simulation, CAG was demonstrated to bind to the active site of autophagy­related gene 4­microtubule­associated proteins light chain 3 complex, which explains the reduced autophagic flux in asthma caused by CAG. The expression levels of proteins associated with autophagy pathways were inhibited following treatment with CAG. Taken together, the results of the present study suggest that CAG exerts an anti­inflammatory effect in asthma, and its role may be associated with the inhibition of autophagy in lung cells.

Cellular clocks in hyperoxia effects on [Ca2+]i regulation in developing human airway smooth muscle.

Supplemental O2 (hyperoxia) is necessary for preterm infant survival but is associated with development of bronchial airway hyperreactivity and childhood asthma. Understanding early mechanisms that link hyperoxia to altered airway structure and function are key to developing advanced therapies. We previously showed that even moderate hyperoxia (50% O2) enhances intracellular calcium ([Ca2+]i) and proliferation of human fetal airway smooth muscle (fASM), thereby facilitating bronchoconstriction and remodeling. Here, we introduce cellular clock biology as a novel mechanism linking early oxygen exposure to airway biology. Peripheral, intracellular clocks are a network of transcription-translation feedback loops that produce circadian oscillations with downstream targets highly relevant to airway function and asthma. Premature infants suffer circadian disruption whereas entrainment strategies improve outcomes, highlighting the need to understand relationships between clocks and developing airways. We hypothesized that hyperoxia impacts clock function in fASM and that the clock can be leveraged to attenuate deleterious effects of O2 on the developing airway. We report that human fASM express core clock machinery (PER1, PER2, CRY1, ARNTL/BMAL1, CLOCK) that is responsive to dexamethasone (Dex) and altered by O2. Disruption of the clock via siRNA-mediated PER1 or ARNTL knockdown alters store-operated calcium entry (SOCE) and [Ca2+]i response to histamine in hyperoxia. Effects of O2 on [Ca2+]i are rescued by driving expression of clock proteins, via effects on the Ca2+ channels IP3R and Orai1. These data reveal a functional fASM clock that modulates [Ca2+]i regulation, particularly in hyperoxia. Harnessing clock biology may be a novel therapeutic consideration for neonatal airway diseases following prematurity.

Qingfei oral liquid alleviates airway hyperresponsiveness and mucus hypersecretion via TRPV1 signaling in RSV-infected asthmatic mice.

Pediatric asthma is exacerbated by Respiratory Syncytial Virus (RSV) infection, and Transient Receptor Potential Vanilloid 1 (TRPV1) promotes production of inflammatory cytokines and mucus hypersecretion in the pathology of this disease. Our previous research revealed that Qingfei oral liquid (QF) inhibited airway inflammation and mucus hypersecretion in RSV-infected asthmatic mice models and that this may be associated with the TRPV1-regulation of NF-κB and Mucin 5AC (MUC5AC) expression, but the exact mechanism is unknown. In the present study, LC-MS was used for analyzing the chemicals in QF, ovalbumin (OVA)-induced asthmatic mice inhaled RSV three consecutive times to create an RSV-infected asthmatic model. We found treatment from QF alleviated airway hyperresponsiveness (AHR) and reduced congestion, edema, and infiltration of inflammatory cells into pulmonary tissues. Additionally, QF was found to decrease expression of NF-κB and its downstream inflammatory cytokines IL-1ß, IL-4, IL-5, and IL-13, as well as a decrease in MUC5AC and pro-inflammatory cytokines in PKC via a reduction in Protein Kinase C-dependent signaling. These findings suggest that QF can alleviate AHR and mucus hypersecretion caused by RSV infection in asthmatic mice, and its mechanism may be associated with the regulation of the TRPV1 signaling pathway.

Myxopyrum serratulum ameliorates airway inflammation in LPS-stimulated RAW 264.7 macrophages and OVA-induced murine model of allergic asthma.

ETHNOPHARMACOLOGICAL RELEVANCE: Myxopyrum serratulum A. W. Hill. (Oleaceae) is a traditionally used Indian medicinal plant for the treatment of cough, asthma and many other inflammatory diseases. AIM OF THE STUDY: In this study, the protective effects of M. serratulum on airway inflammation was investigated in ovalbumin (OVA)-induced murine model of allergic asthma and lipopolysaccharide (LPS)-stimulated inflammation in RAW 264.7 murine macrophages, and the possible mechanisms were elucidated. MATERIALS AND METHODS: The phytochemicals present in the methanolic leaf extract of M. serratulum (MEMS) were identified by reverse phase high performance liquid chromatography (RP-HPLC) analysis. In vitro anti-inflammatory activity of MEMS were evaluated by estimating the levels of nitric oxide (NO), reactive oxygen species (ROS) and cytokines (IL-1α, IL-1ß, IL-2, IL-4, IL-6, IL-10, IL-12, IL-17A, IFN-γ, TNF-α, G-CSF and GM-CSF) in LPS-stimulated RAW 264.7 macrophages. In vivo anti-asthmatic activity of MEMS was studied using OVA-induced murine model. Airway hyperresponsiveness (AHR), was measured; total and differential cell counts, eosinophil peroxidase (EPO), prostaglandin E2 (PGE2), NO, ROS, and cytokines (IL-4, IL-5 and IL-13), were estimated in bronchoalveolar lavage fluid (BALF). Serum total IgE level was measured; and the histopathological changes of lung tissues were observed. The expressions of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in lung tissue homogenates were detected by Western blot. RESULTS: The chromatographic analysis of MEMS identified the presence of gallic acid, protocatechuic acid, catechin, ellagic acid, rutin, p-coumaric acid, quercetin, naringenin and apigenin. MEMS (125 and 250 µg/mL) dose-dependently reduced the levels of NO, ROS and pro-inflammatory cytokines in LPS-stimulated RAW 264.7 macrophages. MEMS (200 and 400 mg/kg, p.o.) significantly (p < 0.05) alleviated AHR; number of inflammatory cells, EPO, PGE2, NO, ROS, and cytokines (IL-4, IL-5 and IL-13) in BALF; serum total IgE and the histopathological changes associated with lung inflammation. Western blot studies showed that MEMS substantially suppressed COX-2 and iNOS protein expressions in the lung tissues of OVA-sensitized/challenged mice. CONCLUSIONS: The present study corroborates for the first time the ameliorative effects of MEMS on airway inflammation by reducing the levels of oxidative stress, pro-inflammatory cytokines and inhibiting COX-2, iNOS protein expressions, thereby validating the ethnopharmacological uses of M. serratulum.

The TLR4-TRIF pathway can protect against the development of experimental allergic asthma.

The Toll-like receptor (TLR) adaptor proteins myeloid differentiating factor 88 (MyD88) and Toll, interleukin-1 receptor and resistance protein (TIR) domain-containing adaptor inducing interferon-ß (TRIF) comprise the two principal limbs of the TLR signalling network. We studied the role of these adaptors in the TLR4-dependent inhibition of allergic airway disease and induction of CD4+ ICOS+ T cells by nasal application of Protollin™, a mucosal adjuvant composed of TLR2 and TLR4 agonists. Wild-type (WT), Trif-/- or Myd88-/- mice were sensitized to birch pollen extract (BPEx), then received intranasal Protollin followed by consecutive BPEx challenges. Protollin's protection against allergic airway disease was TRIF-dependent and MyD88-independent. TRIF deficiency diminished the CD4+ ICOS+ T-cell subsets in the lymph nodes draining the nasal mucosa, as well as their recruitment to the lungs. Overall, TRIF deficiency reduced the proportion of cervical lymph node and lung CD4+ ICOS+ Foxp3- cells, in particular. Adoptive transfer of cervical lymph node cells supported a role for Protollin-induced CD4+ ICOS+ cells in the TRIF-dependent inhibition of airway hyper-responsiveness. Hence, our data demonstrate that stimulation of the TLR4-TRIF pathway can protect against the development of allergic airway disease and that a TRIF-dependent adjuvant effect on CD4+ ICOS+ T-cell responses may be a contributing mechanism.

Imperatorin exerts antiallergic effects in Th2-mediated allergic asthma via induction of IL-10-producing regulatory T cells by modulating the function of dendritic cells.

Imperatorin is a furanocoumarin compound which exists in many medicinal herbs and possesses various biological activities. Herein, we investigated the antiallergic effects of imperatorin in asthmatic mice and explored the immunomodulatory actions of imperatorin on immune cells. We used a murine model of ovalbumin (OVA)-induced asthma to evaluate the therapeutic potential of imperatorin. Additionally, bone marrow-derived dendritic cells (DCs; BMDCs) were used to clarify whether imperatorin exerts an antiallergic effect through altering the ability of DCs to regulate T cells. Oral administration of imperatorin to OVA-sensitized and -challenged mice decreased serum OVA-specific immunoglobulin E (IgE) production, attenuated the airway hyperresponsiveness (AHR), and alleviated airway inflammation in a dose-dependent manner. Notably, secretions of Th2 cytokines and chemokines were reduced, and numbers of interleukin (IL)-10-producing regulatory T cells (Tregs) increased in imperatorin-treated mice. Imperatorin inhibited proinflammatory cytokines and IL-12 production but enhanced IL-10 secretion by lipopolysaccharide (LPS)-stimulated BMDCs. Compared to fully mature DCs, imperatorin-treated DCs expressed high levels of the inducible costimulatory ligand (ICOSL) and Jagged1 molecules, and had the regulatory capacity to promote the generation of IL-10-producing CD4(+) T cells in vitro. Additionally, imperatorin directly suppressed activated CD4(+) T-cell proliferation and cytokine production. Imperatorin may possess therapeutic potential against Th2-mediated allergic asthma not only via stimulating DC induction of Tregs but also via direct inhibition of Th2 cell activation. These findings provide new insights into how imperatorin affects the Th2 immune response and the development of imperatorin as a Treg-type immunomodulatory agent to treat allergic asthma.

Obesity, metabolic syndrome, and airway disease: a bioenergetic problem?

Multiple studies have determined that obesity increases asthma risk or severity. Metabolic changes of obesity, such as diabetes or insulin resistance, are associated with asthma and poorer lung function. Insulin resistance is also found to increase asthma risk independent of body mass. Conversely, asthma is associated with abnormal glucose and lipid metabolism, insulin resistance, and obesity. Here we review our current understanding of how dietary and lifestyle factors lead to changes in mitochondrial metabolism and cellular bioenergetics, inducing various components of the cardiometabolic syndrome and airway disease.

Dietary long-chain omega-3 fatty acids do not diminish eosinophilic pulmonary inflammation in mice.

Although the effects of fish oil supplements on airway inflammation in asthma have been studied with varying results, the independent effects of the fish oil components, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), administered separately, are untested. Here, we investigated airway inflammation and hyperresponsiveness using a mouse ovalbumin exposure model of asthma assessing the effects of consuming EPA (1.5% wt/wt), DHA (1.5% wt/wt), EPA plus DHA (0.75% each), or a control diet with no added omega-3 polyunsaturated fatty acids. Consuming these diets for 6 weeks resulted in erythrocyte membrane EPA contents (molar %) of 9.0 (± 0.6), 3.2 (± 0.2), 6.8 (± 0.5), and 0.01 (± 0.0)%; DHA contents were 6.8 (± 0.1), 15.6 (± 0.5), 12.3 (± 0.3), and 3.8 (± 0.2)%, respectively. The DHA group had the highest bronchoalveolar lavage (BAL) fluid eosinophil and IL-6 levels (P < 0.05). Similar trends were seen for macrophages, IL-4, and IL-13, whereas TNF-α was lower in omega-3 polyunsaturated fatty acid groups than the control (P < 0.05). The DHA group also had the highest airway resistance, which differed significantly from the EPA plus DHA group (P < 0.05), which had the lowest. Oxylipins were measured in plasma and BAL fluid, with DHA and EPA suppressing arachidonic acid-derived oxylipin production. DHA-derived oxylipins from the cytochrome P450 and 15-lipoxygenase pathways correlated significantly with BAL eosinophil levels. The proinflammatory effects of DHA suggest that the adverse effects of individual fatty acid formulations should be thoroughly considered before any use as therapeutic agents in asthma.

The effects of pycnogenol on antioxidant enzymes in a mouse model of ozone exposure.

BACKGROUND/AIMS: Ozone is an environmentally reactive oxidant, and pycnogenol is a mixture of flavonoid compounds extracted from pine tree bark that have antioxidant activity. We investigated the effects of pycnogenol on reactive nitrogen species, antioxidant responses, and airway responsiveness in BALB/c mice exposed to ozone. METHODS: Antioxidant levels were determined using high performance liquid chromatography with electrochemical detection. Nitric oxide (NO) metabolites in bronchoalveolar lavage (BAL) fluid from BALB/c mice in filtered air and 2 ppm ozone with pycnogenol pretreatment before ozone exposure (n = 6) were quantified colorimetrically using the Griess reaction. RESULTS: Uric acid and ascorbic acid concentrations were significantly higher in BAL fluid following pretreatment with pycnogenol, whereas γ-tocopherol concentrations were higher in the ozone exposed group but were similar in the ozone and pycnogenol pretreatment groups. Retinol and γ-tocopherol concentrations tended to increase in the ozone exposure group but were similar in the ozone and pycnogenol pretreatment groups following ozone exposure. Malonylaldehyde concentrations increased in the ozone exposure group but were similar in the ozone and pycnogenol plus ozone groups. The nitrite and total NO metabolite concentrations in BAL fluid, which parallel the in vivo generation of NO in the airways, were significantly greater in the ozone exposed group than the group exposed to filtered air, but decreased with pycnogenol pretreatment. CONCLUSIONS: Pycnogenol may increase levels of antioxidant enzymes and decrease levels of nitrogen species, suggesting that antioxidants minimize the effects of acute ozone exposure via a protective mechanism.

Curcumin attenuates allergic airway inflammation by regulation of CD4+CD25+ regulatory T cells (Tregs)/Th17 balance in ovalbumin-sensitized mice.

The present study aimed to determine the protective effects and the underlying mechanisms of curcumin on ovalbumin (OVA)-induced allergic inflammation in a mouse model of allergic asthma. Asthma mice model was established by ovalbumin. A total of 60 mice were randomly assigned to six experimental groups: control, model, dexamethasone (2 mg/kg), and curcumin (50 mg/kg, 100 mg/kg, 200 mg/kg). Airway resistance (Raw) was measured by the forced oscillation technique, differential cell count in BAL fluid (BALF) was measured by Wright-Giemsa staining, histological assessment was measured by hematoxylin and eosin (HE) staining, BALF levels of Treg/Th17 cytokines were measured by enzyme-linked immunosorbent assay, Treg cells and Th17 cells were evaluated by flow cytometry (FCM). Our study demonstrated that curcumin inhibited OVA-induced increases in eosinophil count; interleukin (IL)-17A level were recovered in bronchoalveolar lavage fluid increased IL-10 level in bronchoalveolar lavage fluid. Histological studies demonstrated that curcumin substantially inhibited OVA-induced eosinophilia in lung tissue. Flow cytometry (FCM) studies demonstrated that curcumin remarkably inhibited Th17 cells and significantly increased Treg cells. The results in vivo show ovalbumin-induced significantly broke Treg/Th17 balance; curcumin treatments markedly attenuated the inflammatory in asthma model by regulating Treg/Th17 balance. Our findings support the possible use of curcumin as a therapeutic drug for patients with allergic asthma.

Molecular mechanisms underpinning laser printer and photocopier induced symptoms, including chronic fatigue syndrome and respiratory tract hyperresponsiveness: pharmacological treatment with cinnamon and hydrogen.

Emissions of laser printers and photocopiers (LP&P) may be associated with health problems. The aim of this review is to describe the clinical picture that is triggered by exposure to LP&P and the molecular mechanisms underpinning the symptoms. Exposure to LP&P to vulnerable subjects may cause a symptom complex consisting of 1) irritation and hyperresponsiveness of the upper and lower respiratory tract; and 2) chronic fatigue (syndrome, CFS). Symptoms occur within hours after L&P exposure and may last for some days or become chronic with exacerbations following LP&P exposure. Substances that can be found in toners or are generated during the printing process are Silica nanoparticles, Titanium Dioxide nanoparticles, Carbon Black, metals, ozone, volatile organic compounds (VOC), etc. The latter may generate oxidative and nitrosative stress (O&NS), damage-associated molecular patterns molecules, pulmonary and systemic inflammation, and modulate Toll Like Receptor 4 (TRL4)­related mechanisms. It is concluded that LP&P emissions may cause activation of the TLR4 Radical Cycle and thus be associated with the onset of chronic inflammatory and O&NS illnesses, such as CFS, in some vulnerable individuals. Cinnamon, an antagonist of the TLR4 complex, and Hydrogen, a potent antiinflammatory and oxygen radical scavenger, may have efficacy treating LP&P-induced illness.

Astragalus extract attenuates allergic airway inflammation and inhibits nuclear factor κB expression in asthmatic mice.

BACKGROUND: Astragalus membranaceus from traditional Chinese herbal medicines previously showed that it possesses a strong anti-inflammatory activity. The purpose of this study was to elucidate the effect of astragalus on allergen-induced airway inflammation and airway hyperresponsiveness and investigate its possible molecular mechanisms. METHODS: Female BALB/c mice sensitized and challenged with ovalbumin (OVA) developed airway inflammation. Bronchoalveolar lavage fluid was assessed for total and differential cell counts and cytokine and chemokine levels. In vivo airway responsiveness to increasing concentrations of methacholine was measured 24 hours after the last OVA challenge using whole-body plethysmography. The expression of inhibitory κB-α and p65 in lung tissues was measured by Western blotting. RESULTS: Astragalus extract attenuated lung inflammation, goblet cell hyperplasia and airway hyperresponsiveness in OVA-induced asthma and decreased eosinophils and lymphocytes in bronchoalveolar lavage fluid. In addition, astragalus extract treatment reduced expression of the key initiators of allergic T(H)2-associated cytokines (interleukin 4, interleukin 5) (P < 0.05). Furthermore, astragalus extract could inhibit nuclear factor κB (NF-κB) expression and suppress NF-κB translocation from the cytoplasm to the nucleus in lung tissue samples. CONCLUSIONS: Taken together, our current study demonstrated a potential therapeutic value of astragalus extract in the treatment of asthma and it may act by inhibiting the expression of the NF-κB pathway.

Effects and mechanism of arsenic trioxide on reversing the asthma pathologies including Th17-IL-17 axis in a mouse model.

In traditional Chinese medicine, arsenous compounds, including arsenic trioxide (ATO), are often used to treat many diseases, which are safe and effective. Recently, studies have indicated that Th17- IL-17 involved in the pathogenesis and development of asthma. The goal of this study was to investigate the effect and mechanism of ATO on asthma, especially the Th17- IL-17 axis.We used oval bumin (OVA)-immunized mice as a model for asthma and treated mice with ATO or dexamethasone. The mice were then monitored airway responsiveness, airway inflammation, mucus production, IL-17 levels in BALF and the positive rate of Th17 cells. In vitro, CD4+ T cells from splenic cell suspensions were separated and purified. We measured the expression of IL-17 and caspase-12 protein in purified CD4+ T cells, and detected IL-17 levels in CD4+ T lymphocyte culture solution with or without ATO. Moreover, apoptosis, mitochondrial membrane potential, cytosolic calcium were analyzed. We found that ATO could reduce airway responsiveness, airway inflammation, mucus hyperplasia, the expression of IL-17 in BALF and the positive rate of Th17 cells at a level comparable to treatment with DXM. In vitro data suggested that ATO can induce CD4+ T cells apoptosis, cause mitochondrial dysfunction, Ca2+ overload and promote caspase-12 activation. Our study suggested that ATO had potential medical value for the treatment of human asthma..

Triphala (PADMA) extract alleviates bronchial hyperreactivity in a mouse model through liver and spleen immune modulation and increased anti-oxidative effects.

OBJECTIVES: Triphala (TRP), a herbal extract from Tibetan medicine, has been shown to affect lymphocytes and natural killer T (NKT) cell function. We hypothesize that TRP could ameliorate bronchial hyperreactivity through immune-cell modulations. METHODS: Asthma mouse models were generated through intraperitoneal (IP) injections of ovalbumin (OVA)/2 weeks followed by repeated intranasal OVA challenges. Mice were then treated with normal saline (OVA/NS) or Triphala (OVA/TRP). Data were compared with mice treated with inhaled budesonide. All groups were assessed for allergen-induced hyperreactivity; lymphocytes from lungs, livers and spleens were analyzed for OVA-induced proliferation and their alterations were determined by flow cytometry. Oxidative reactivity using chemiluminescence, serum anti-OVA antibodies level and lung histology were assessed. RESULTS: Both TRP and budesonide significantly ameliorated functional and histological OVA-induced bronchial hyperreactivity. TRP had no effect on serum anti-OVA antibodies as compared with decreased levels following budesonide treatment. Furthermore, a significant increase in lung and spleen CD4 counts and a decrease in the liver were noted after TRP treatments. Bronchoalveolar fluid from TRP-treated animals but not from the budesonide-treated animals showed anti-oxidative effects. CONCLUSION: TRP and budesonide caused a significant decrease in bronchial reactivity. TRP treatment altered immune-cell distributions and showed anti-oxidative properties. These findings suggest that immune-cell modulation with TRP can ameliorate lung injury.

Xiao-Qing-Long-Tang attenuates allergic airway inflammation and remodeling in repetitive Dermatogoides pteronyssinus challenged chronic asthmatic mice model.

ETHNOPHARMACOLOGICAL RELEVANCE: Xiao-Qing-Long-Tang (XQLT) has been used for centuries in Asia to effectively treat patients with bronchial asthma. AIM OF THE STUDY: We previously found that single and multiple doses of XQLT administered to sensitized mice before allergen challenge resulted in suppressed airway hyper-responsiveness and airway inflammation. In this study we aimed to investigate whether XQLT has the potential to attenuate the severity of asthma symptoms, and immunomodulatory mechanism of XQLT in a repetitive Dermatogoides pteronyssinus (D. pteronyssinus)-challenged chronic asthmatic mice model. MATERIALS AND METHODS: BALB/c mice were intratracheally (i.t.) inoculated with five doses of D. pteronyssinus (50 µl, 1mg/ml) and orally administered of XQLT (1 g/kg) at 1-week intervals. At three days after the last challenge, mice were sacrificed to evaluate airway remodeling, inflammation, lung histological features, and the expression profiles of cytokines and various genes. RESULTS: XQLT significantly reduced bronchial inflammatory cell infiltration and airway remodeling. It inhibited D. pteronyssinus-induced total IgE and D. pteronyssinus-specific IgG1 in serum, and changed the "T(H)2-bios" in BALF by inhibiting the activation of NF-κB. Collagen assay and Histopathology indicated that XQLT reduced airway remodeling in the lung. Simultaneously, the RT-PCR analysis showed that XQLT downregulated IL-10, IL-13, RANTES, Eotaxin, and MCP-1 mRNA expression in the lung. Moreover, EMSA and immunohistochemistry staining demonstrated that XQLT inhibited NF-κB expression in the nucleus of bronchial epithelial cells. CONCLUSIONS: These results suggest that XQLT exhibits anti-airway inflammatory, anti-airway remodeling, and specific immunoregulatory effects in a chronic asthmatic mice model.

Partially purified extract and viscolin from Viscum coloratum attenuate airway inflammation and eosinophil infiltration in ovalbumin-sensitized mice.

AIM OF THE STUDY: Viscum coloratum Nakai is used in traditional Chinese medicine to treat various diseases, including hemorrhage, hypertension, and inflammatory diseases. A previous study demonstrated a partially purified extract (PPE-SVC) and viscolin from Viscum coloratum Nakai inhibited phosphodiesterase activity. In this study, we evaluated the anti-asthmatic effects of PPE-SVC and viscolin, from Viscum coloratum Nakai, in OVA-sensitized mice. MATERIALS AND METHODS: Female BALB/c mice were sensitized and challenged with ovalbumin (OVA). The mice were randomized into groups and treated with PPE-SVC, viscolin, or rolipram by intraperitoneal injection on 1h before each inhalation of OVA and airway hyperresponsiveness (AHR). RESULTS: PPE-SVC and viscolin suppressed AHR and reduced eosinophil infiltration of the lungs in OVA-sensitized mice. Moreover, PPE-SVC and viscolin inhibited chemokines, including CCL11 and CCL24, and Th2-associated cytokines in bronchoalveolar lavage fluid. However, PPE-SVC and viscolin could not decrease IL-4, IL-5, and IL-13 levels in cultures of OVA-activated spleen cells. CONCLUSION: PPE-SVC and viscolin attenuate airway inflammation and eosinophil infiltration in OVA-sensitized mice.

Inhibition of airway inflammation, hyperresponsiveness and remodeling by soy isoflavone in a murine model of allergic asthma.

Epidemiologic studies have associated higher dietary consumption of soy isoflavones with decreased self-report of cough and allergic respiratory symptoms, but the pharmacodynamic effects of soy isoflavone on asthmatic model have not been well-described. Here, we hypothesized that soy isoflavone may have potential effects on airway hyperresponsiveness, inflammation and airway remodeling in a murine of asthma. Mice sensitized and challenged with ovalbumin developed airway inflammation. Bronchoalveolar lavage fluid was assessed for inflammatory cell counts, and for cytokine levels. Lung tissues were examined for cell infiltration, mucus hypersecretion and airway remodeling, and for the expression of inflammatory biomarkers. Airway hyperresponsiveness was monitored by direct airway resistance analysis. Oral administration of soy isoflavone significantly reduced ovalbumin-induced airway hyperresponsiveness to intravenous methacholine, and inhibited ovalbumin-induced increases in eosinophil counts. RT-PCR analysis of whole lung lysates revealed that soy isoflavone markedly suppressed ovalbumin-induced mRNA expression of eotaxin, interleukin(IL)-5, IL-4 and matrix metalloproteinase-9, and increased mRNA expression of interferon (IFN)-γ and tissue inhibitor of metalloproteinase-1 in a dose-dependent manner. Soy isoflavone also substantially recovered IFN-γ/IL-4 (Th1/Th2) levels in bronchoalveolar lavage fluid. In addition, histologic studies showed that soy isoflavone dramatically inhibited ovalbumin-induced lung tissue eosinophil infiltration, airway mucus production and collagen deposition in lung tissues. Our findings suggest that soy isoflavone as nutritional supplement may provide a novel means for the treatment of airway inflammatory disease.

Effects of astragaloside IV on IFN-gamma level and prolonged airway dysfunction in a murine model of chronic asthma.

Astragaloside IV (AST) is the main active constituent of Radix Astragali, a Chinese herb traditionally used to prevent asthma attack from chronic asthma patients. Its efficacy and action mechanisms in asthma attack prevention remain nonetheless to be further explored. In this study, chronic asthma was induced exposing ovalbumin (OVA) sensitized mice to repeated OVA challenges twice every two weeks for 12 weeks. Mice were treated with AST for 4 weeks just after the final challenge. In this murine model of chronic asthma, the airway dysfunction and remodeling remained severe and was accompanied with suppression of the IFN-gamma level in the bronchoalveolar lavage fluid (BALF) even four weeks after the final challenge, indicating that the airway structural changes continued to develop even after interruption of OVA challenges. However, after AST treatment, the airway hyperresponsiveness was sharply relieved, accompanied by the reduction of collagen deposition and mucus production, meanwhile the inflammatory cells were decreased but the IFN-gamma level increased in BALF. In conclusion, AST could prevent the development of chronic asthma, thus reducing asthma attacks. Our results indicated that it should be used as a supplementary therapy on preventing asthma attacks from chronic asthma patients.

A standardized aqueous extract of Anoectochilus formosanus modulated airway hyperresponsiveness in an OVA-inhaled murine model.

Anoectochilus formosanus HAYATA, a Chinese herb, is a valued folk medicine for fever, pain, and diseases of the lung and liver. Allergic asthma is characterized by increased serum IgE level and inflammation of the airways with high levels of interleukin (IL)-4 and IL-5 in bronchoalveolar lavage fluids (BALF). Constriction of airway smooth muscle and development of airway hyperresponsiveness (AHR) are the most important symptoms of allergic asthma. In our previous study, a standardized aqueous extract of A. formosanus (SAEAF) was used to modulate innate immunity of normal mice. In this study, airway inflammatory infiltrations, including T cell differentiation, cytokine modulation, allergic antibodies estimation, pulmonary pathology, and enhanced pause (Penh) of AHR were used to evaluate SAEAF treatment of an ovalbumin (OVA)-inhaled airway allergic murine model. The resulting cytokine profiles demonstrated that SAEAF can significantly reduce Th2 polarization after administration of SAEAF in OVA inhalation. These results also suggest that SAEAF modulates cytokine secretion in allergic asthma. Modulated natural T regulatory cells (CD25+/CD4+, Treg) were also shown to increase immuno-suppression in the allergic lung inflammation and further down-regulate airway inflammatory infiltration in eosinophils and macrophages. Finally, decreased airway anti-OVA IgE secretion and reduced AHR were observed. Our results indicate that the administration of SAEAF can modulate cytokines and T cell subpopulation by regulating inflammatory cell infiltration and modulating the allergic response.

The plant extract Isatis tinctoria L. extract (ITE) inhibits allergen-induced airway inflammation and hyperreactivity in mice.

BACKGROUND: The herbal Isatis tinctoria extract (ITE) inhibits the inducible isoform of cyclooxygenase (COX-2) as well as lipoxygenase (5-LOX) and therefore possesses anti-inflammatory properties. The extract might also be useful in allergic airway diseases which are characterized by chronic inflammation. METHODS: ITE obtained from leaves by supercritical carbon dioxide extraction was investigated in ovalbumin (OVA) immunised BALB/c mice given intranasally together with antigen challenge in the murine model of allergic airway disease (asthma) with the analysis of the inflammatory and immune parameters in the lung. RESULTS: ITE given with the antigen challenge inhibited in a dose related manner the allergic response. ITE diminished airway hyperresponsiveness (AHR) and eosinophil recruitment into the bronchoalveolar lavage (BAL) fluid upon allergen challenge, but had no effect in the saline control mice. Eosinophil recruitment was further assessed in the lung by eosinophil peroxidase (EPO) activity at a dose of 30 microg ITE per mouse. Microscopic investigations revealed less inflammation, eosinophil recruitment and mucus hyperproduction in the lung in a dose related manner. Diminution of AHR and inflammation was associated with reduced IL-4, IL-5, and RANTES production in the BAL fluid at the 30 microg ITE dose, while OVA specific IgE and eotaxin serum levels remained unchanged. CONCLUSION: ITE, which has been reported inhibiting COX-2 and 5-LOX, reduced allergic airway inflammation and AHR by inhibiting the production of the Th2 cytokines IL-4 and IL-5, and RANTES.