Anti-inflammatory and anti-asthmatic effects of Viola mandshurica W. Becker (VM) ethanolic (EtOH) extract on airway inflammation in a mouse model of allergic asthma

Anti-inflammatory effect of Trichospira verticillata via suppression of the NLRP3 inflammasome in neutrophilic asthma

Trichospira verticillata is an annual herb that belongs to the family Asteraceae. Trichospira verticillata extract (TVE) elicits anti-plasmodial activity; however, there has been no detailed report about its anti-inflammatory effects and molecular mechanisms. In addition, herbal plants exhibit anti-inflammatory effects by suppressing the NLRP3 inflammasome. Therefore, the primary goal of this study was to examine the effects of TVE on NLRP3 inflammasome activation by measuring interleukin-1β (IL-1β) secretion. We treated lipopolysaccharides (LPS)-primed J774A.1 and THP-1 cells with TVE, which attenuated NLRP3 inflammasome activation. Notably, TVE did not affect nuclear factor-kappa B (NF-κB) signalling or intracellular reactive oxygen species (ROS) production and potassium efflux, suggesting that it inactivates the NLRP3 inflammasome via other mechanisms. Moreover, TVE suppressed the formation of apoptosis-associated speck-like protein (ASC) speck and oligomerization. Immunoprecipitation data revealed that TVE reduced the binding of NLRP3 to NIMA-related kinase 7 (NEK7), resulting in reduced ASC oligomerization and speck formation. Moreover, TVE alleviated neutrophilic asthma (NA) symptoms in mice. This study demonstrates that TVE modulates the binding of NLPR3 to NEK7, thereby reporting novel insights into the mechanism by which TVE inhibits NLRP3 inflammasome. These findings suggest TVE as a potential therapeutic of NLRP3 inflammasome-mediated diseases, particularly NA.

Medicinal Plant-derived Phytochemicals in Detoxification

The average worldwide human life expectancy is 70 years, with a significantly higher value in Western societies. Many modern diseases are not associated with premature mortality but with a decreased quality of life in aged patients and an excessive accumulation of various toxic compounds in the human body during life. Today, scientists are especially interested in finding compounds that can help increase a healthy lifespan by detoxifying the body. Phytotherapy with specific approaches is used in alternative medicine to remove toxins from the body. Worldwide, research is conducted to identify medicinal plant-derived molecules that, with few or no side effects, may protect the liver and other organs. This review provides updated information about the detoxification process, the traditional and modern use of the most effective medicinal plants, their active metabolites as detoxifying agents, and the mechanisms and pathways involved in the detoxification process. Among medicinal plants with substantial detoxifying properties, a major part belongs to the Asteraceae family (Silybum marianum, Cynara scolymus, Arctium lappa, Helichrysum species, Inula helenium, and Taraxacum officinale). The most widely used hepatoprotective phytocomponent is silymarin, a standardized extract from the Silybum marianum seeds containing a mixture of flavonolignans. Many polysaccharides, polyphenols, and terpenoids have a detoxifying effect. Overall, scientific data on medicinal plants used in phytotherapeutic practice worldwide provides an understanding and awareness of their efficacy in detoxification.

A Systematic Review of Phytochemistry, Nutritional Composition, and Pharmacologic Application of Species of the Genus Viola in Noncommunicable Diseases (NCDs)

Viola L. is the largest genus of the Violaceae family with more than 500 species across the globe. The present extensive literature survey revealed Viola species to be a group of important nutritional and medicinal plants used for the ethnomedicinal treatment of noncommunicable diseases (NCDs) such as diabetes, asthma, lung diseases, and fatigue. Many plant species of this genus have also received scientific validation of their pharmacological activities including neuroprotective, immunomodulatory, anticancer, antihypertensive, antidyslipidemic, analgesic, antipyretic, diuretic, anti-inflammatory, anthelmintic, and antioxidant. Viola is highly rich in different natural products some of which have been isolated and identified in the past few decades; these include flavonoids terpenoids and phenylpropanoids of different pharmacological activities. The pharmacokinetics and clinical studies on this genus are lacking, and the present review is aimed at summarizing the current understanding of the ethnopharmacology, phytochemistry, nutritional composition, and pharmacological profile of medicinal plants from the Viola genus to reveal its therapeutic potentials, gaps, and subsequently open a new window for future pharmacological research.

A comprehensive review of phytochemistry, pharmacology and quality control of plants from the genus Viola

OBJECTIVES

The genus Viola belongs to the family Violaceae, and the plants from this genus are essential folk herb medicine extensively used in many areas. The plants from the genus Viola are used to treat various diseases and exert a significant role in protecting people's health. This review summarized the genus Viola plants' phytochemistry, pharmacology, and quality control methods.

KEY FINDINGS

The information on chemical constituents and pharmacological effects of the genus Viola was obtained by searching the Web of Science, Pubmed, CNKI, and other databases. A total of 208 valuable articles were selected and analyzed in this review. The main chemical components of plants from the genus Viola consist of flavonoids, coumarins, alkaloids, lignans, sesquiterpenes, cyclotides, etc. The active chemical components of medicinal plants from this genus exert antibacterial, antiviral, antioxidant, anti-inflammatory, anti-tumor, neuroprotective, hepatoprotective activities, and so on. The quality control of these plants is not sufficient and needs further research.

SUMMARY

The chemical constituents, pharmacological effects, and quality control of plants from the genus Viola were systematically summarized in this paper, and this review provides a literature basis for the further research of plants from this genus.

Standardized Extract of Atractylodis Rhizoma Alba and Fructus Schisandrae Ameliorates Coughing and Increases Expectoration of Phlegm

Cough and phlegm frequently occur in respiratory diseases like upper respiratory tract infections, acute bronchitis, and chronic obstructive pulmonary diseases. To relieve these symptoms and diseases, various ingredients are being used despite the debates on their clinical efficacy. We aimed to investigate the effects of the extract CKD-497, composed of Atractylodis Rhizoma Alba and Fructus Schisandrae, in relieving cough and facilitating expectoration of phlegm. CKD-497 was found to inhibit inflammatory mediators such as interleukin-8 (IL-8) and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-treated mouse macrophages and transient receptor potential cation channel 1 (TRPV-1)-overexpressed human bronchial epithelial cells stimulated by capsaicin. CKD-497 decreased the viscosity of the mucin solution. During in vivo experiments, CKD-497 reduced coughing numbers and increased expectoration of phlegm via mucociliary clearance enhancement. Collectively, these data suggest that CKD-497 possesses potential for cough and phlegm expectoration treatment.

Modulation of interleukin expression by medicinal plants and their secondary metabolites: A systematic review on anti-asthmatic and immunopharmacological mechanisms

BACKGROUND

Asthma is one of the most common chronic inflammatory conditions of the lungs in modern society. Asthma is associated with airway hyperresponsiveness and remodeling of the airways, with typical symptoms of cough, wheezing, shortness of breath and chest tightness. Interleukins (IL) play an integral role in its inflammatory pathogenesis. Medicinal herbs and secondary metabolites are gaining considerable attention due to their potential therapeutic role and pharmacological mechanisms as adjunct tools to synthetic bronchodilator drugs.

PURPOSE

To systematically review the literature on the use of single or mixed plants extracts therapy in vivo experimental systems for asthma, emphasizing their regulations on IL production to improve lung.

METHODS

Literature searches were performed on PubMed, EMBASE, Scopus and Web of Science databases. All articles in English were extracted from 1999 up to September 2019, assessed critically for data extraction. Studies investigating the effectiveness and safety of plant extracts administered; inflammatory cell count, immunoglobulin E (IgE) production and regulation of pro-inflammatory cytokine and T helper (Th) 1 and Th2-driven cytokine expression in bronchoalveolar lavage fluid (BALF) and lung of asthmatic animals were included.

RESULTS

Four hundred and eighteen publications were identified and 51 met the inclusion criteria. Twenty-six studies described bioactive compounds from plant extracts. The most frequent immunopharmacological mechanisms described included reduction in IgE and eosinophilic recruitment, decreased mucus hypersecretion and airway hyperreactivity, enhancement of the balance of Th1/Th2 cytokine ratio, suppression of matrix metallopeptidase 9 (MMP-9) and reversal of structural alterations.

CONCLUSION

Plant extract therapies have potential control activities on asthma symptoms by modulating the secretion of pro-inflammatory (IL-1β, IL-8), Th17 (IL-17), anti-inflammatory (IL-10, IL-23, IL-31, IL-33), Th1 (IL-2, IL-12) and Th2 (IL-4, IL-5, IL-6, IL-13) cytokines, reducing the level of biomarkers of airway inflammation.

Anti-obesity activity, acute toxicity, and chemical constituents of aqueous and ethanol Viola mandshurica extracts

Background

Viola mandshurica has traditionally been used as an expectorant, diuretic, and anti-inflammatory drug. The present study was designed to test the hypothesis that low doses of two different V. mandshurica extracts have anti-obesity effects.

Methods

We evaluated the effects of ethanol extract (VME) and aqueous extract (VMA) from V. mandshurica on high-fat diet (HFD)-induced obese mice as well as the acute oral toxicities and chemical compositions of both extracts.

Results

Oral administration of VME or VMA (50, 100, or 200 mg/kg) decreased body weight gain, liver and adipose tissue mass, adipocyte size, and serum lipid levels. Both extracts increased adiponectin serum concentrations and mRNA expression in epididymal adipose tissue. VME and VMA also reversed the HFD-induced mRNA expression of lipogenic genes such as CCAAT/enhancer binding protein (C/EBP)α, C/EBPβ, sterol regulatory element-binding protein 1c, and leptin in adipose tissue, whereas they increased mRNA expression of uncoupling protein 2 and adenosine monophosphate-activated protein kinase (AMPK). VME and VMA increased the phosphorylation of AMPK and acetyl-coA carboxylase with a concomitant decrease in fat accumulation in the liver. High performance liquid chromatography analysis revealed that both VME and VMA contained esculetin (0.566% for VME, 0.231% for VMA) and schaftoside (0.147% for VME, 0.126% for VMA). In a 2-week acute toxicity study, administration of a single oral dose of VME or VMA (5000 mg/kg) caused no signs of toxicity or mortality.

Conclusions

These results suggest that both VM extracts exert anti-obesity effects in HFD-induced obese mice by suppressing lipogenesis and activating AMPK in the liver and adipose tissue. Our findings suggest that VM extracts could be a safe and effective treatment for obesity.

Effects of Viola mandshurica on Atherosclerosis and Hepatic Steatosis in ApoE−∕− via the AMPK Pathway

Atherosclerosis was previously thought to be a disease that primarily involves lipid accumulation in the arterial wall. In this report, we investigated the effect of Viola mandshurica W. Becker (V. mandshurica) water extract on atherosclerosis in apolipoprotein E deficient (ApoE[Formula: see text]) mice. The administration of V. mandshurica to high-fat diet-fed mice reduced body weight, liver weight, and serum levels of lipids (total cholesterol, low-density lipoprotein-cholesterol, triglycerides), glucose, alanine transaminase, and aspartate transaminase. Histopathologic analyses of the aorta and liver revealed that V. mandshurica attenuated atherosclerotic lesions and reduced lipid accumulation, inflammatory responses and fatty acid synthesis. V. mandshurica also increased phosphorylation of adenosine monophosphate-activated protein kinase (AMPK), thereby reducing acetyl-CoA carboxylase (ACC) in liver tissue and inhibiting sterol regulatory element-binding protein 1c (SREBP-1c). V. mandshurica reduced protein expression levels of adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin) as well as ACC, fatty acid synthase, and SREBP-1c. In addition, quantitative analysis of V. mandshurica by high-performance liquid chromatography revealed the presence of esculetin and scopoletin. Esculetin and scopoletin reduced adhesion molecules in human aortic smooth muscle cells. Our results indicate that the anti-atherosclerotic effects of V. mandshurica may be associated with activation of the AMPK pathway. Therefore, AMPK-dependent phosphorylation of SREBP-1c by V. mandshurica may be an effective therapeutic strategy for combatting atherosclerosis and hepatic steatosis.

Phytochemical profiles and inhibitory effects of Tiger Milk mushroom (Lignosus rhinocerus) extract on ovalbumin-induced airway inflammation in a rodent model of asthma

Background

Lignosus rhinocerus (L. rhinocerus), which is known locally as Tiger Milk mushroom, is traditionally used in the treatment of asthma by indigenous communities in Malaysia. However, to date, its efficacy on asthma has not been confirmed by scientific studies and there is also sparse information available on its active constituents. In this study, the volatile constituent of L. rhinocerus hot water extract was investigated using gas chromatography mass spectrometry (GC-MS). The potential effects of L. rhinocerus extract for anti-asthmatic activity was further investigated on ovalbumin (OVA)-sensitized asthmatic Sprague Dawley rats.

Methods

Sequential extraction using five solvents (petroleum ether, diethyl ether, hexane, ethyl acetate and methanol) was conducted prior to GC-MS analysis. Male Sprague Dawley rats were divided into the following four groups of five animals each: 1) normal rats, 2) sensitization plus OVA-challenged rats 3) sensitization plus OVA-challenged with L. rhinocerus treatment and 4) sensitization plus OVA-challenged with dexamethasone treatment. The levels of immunoglobulin E (IgE) in the serum and T-helper 2 cytokines, including interleukin (IL)-4, IL-5 and IL-13, in bronchoalveolar lavage fluid (BALF), as well as eosinophil infiltration in the lungs, were investigated.

Results

GC-MS analysis revealed the presence of five main groups (alkane, fatty acids, benzene, phenol and dicarboxylic acid) with a total of 18 constituents. Linoleic acid (21.35 %), octadecane (11.82 %) and 2,3-dihydroxypropyl elaidate (10.47 %) were present in high amounts. The extract significantly ameliorated the increase in total IgE in serum and IL-4, IL-5 and IL-13 levels in BALF and also effectively suppressed eosinophils numbers in BALF while attenuating eosinophil infiltrations in the lungs.

Conclusion

L. rhinocerus hot water extract has the potential to be used as an alternative for the treatment of acute asthma.

The Effect of Viola odorata Flower Syrup on the Cough of Children With Asthma: A Double-Blind, Randomized Controlled Trial

This study aimed to investigate the effect of violet syrup on cough alleviation in children with intermittent asthma. In a parallel, double-blind, randomized controlled trial, 182 children aged 2 to 12 years with intermittent asthma were randomly assigned 1:1 to receive violet syrup or placebo along with the common standard treatments in both groups (short-acting β-agonist). Both groups were evaluated in terms of the duration until cough suppression was achieved. No significant difference was observed in basic characteristics. The duration lasting to yield more than 50% cough reduction and 100% cough suppression was significantly less in the violet syrup group compared to placebo (P = .001, P < .001, respectively). There was no significant difference in therapeutic effects between boys and girls. There was a significant inverse correlation between the age of children and rate of cough alleviation and suppression by violet syrup. This study showed that the adjuvant use of violet syrup with short-acting β-agonist can enhance the cough suppression in children with intermittent asthma.

The upregulated expression of OX40/OX40L and their promotion of T cells proliferation in the murine model of asthma

OBJECTIVE

To investigate whether the expression of OX40/OX40 ligand (OX40L) was upregulated in a murine model of asthma and their significance in the pathogenesis of asthma.

METHODS

After an ovalbumin-sensitized/challenged murine model of asthma was established, the expressions of OX40, OX40L in peripheral blood mononuclear cells (PBMCs) and bronchoalveolar lavage fluid (BALF) cell pellets were measured. Then T cell proliferation was analyzed by cell counting kit-8 (CCK8), and the protein levels of OX40 and OX40L in the lungs were determined by immunohistochemistry. The concentrations of IL-4 and IFN-γ in BALF and T cell culture supernatant were evaluated by ELISA.

RESULTS

The percentages of CD4(+)OX40(+), CD19(+)OX40L(+), F4/80(+)OX40L(+) in PBMCs and BALF cell pellets were higher in asthma group than in control group (all P<0.01). The proliferation capacity of T cells in asthma group was higher than that in control group (P<0.05). In asthma group, stimulation of OX40 by anti-OX40 mAb obviously promoted T cell proliferation and secretion of IL-4 and IFN-γ. Immunohistochemistry assay showed that OX40 and OX40L protein levels were higher in asthma group than those in control group (all P<0.05).

CONCLUSIONS

The expressions of OX40 and OX40L were upregulated in the murine asthmatic model. The upregulation of OX40/OX40L signals could induce the proliferation and cytokines secretion of T cells in asthmatic mice, indicating that OX40/OX40L signal was involved in the pathogenesis of asthma.

Viola mandshurica ethanolic extract prevents high-fat-diet-induced obesity in mice by activating AMP-activated protein kinase

Viola mandshurica W. Becker has been used as an expectorant, diuretic, and anti-inflammatory agent. We evaluated the effects of V. mandshurica ethanol extract (VME) on high-fat-diet (HFD)-induced obesity in mice. HPLC analysis showed that the VME contained 11.95 ± 0.37 mg/g esculetin and 0.13 ± 0.01 mg/g scopoletin. Orally administered VME decreased the body weight, adipose tissue mass, adipocyte size, and triglyceride and leptin serum concentrations. In contrast, VME increased serum adiponectin concentrations and adiponectin expression levels in epididymal adipose tissues. VME also significantly reversed the HFD-induced elevation of the mRNA and protein levels of lipogenic genes such as peroxisome proliferator-activated receptor γ, sterol regulatory element-binding protein-1c, fatty-acid synthase, and adipocyte protein 2. Moreover, VME reversed the HFD-induced inhibition of AMP-activated protein kinase (AMPK) and acetyl-coA carboxylase phosphorylation in epididymal adipose tissues. Furthermore, treatment of VME and esculetin in 3T3-L1 cells inhibited adipocyte differentiation and fat accumulation. These results suggest that VME exerts anti-obesity effects in HFD-induced obese mice by activating AMPK and suppressing PPARγ expression in adipose tissues.

Tinospora cordifolia extract modulates COX-2, iNOS, ICAM-1, pro-inflammatory cytokines and redox status in murine model of asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Tinospora cordifolia (Willd.) Miers is an important constituent of several ayurvedic medicinal preparations. In Ayurveda it is mentioned as "rasayan" and traditionally used for the treatment of asthma, chronic cough besides other ailments. This study was carried out to study the mechanisms involved in protection accorded by extract of Tinospora cordifolia (Tc) stem to asthmatic mice by regulation of oxidative stress, pro-inflammatory mediator release and redox signaling involving NFκB.

MATERIALS AND METHODS

BALB/c mice were sensitized with intraperitoneal (i.p.) Ovalbumin (Ova) on days 0 and 14, followed by intranasal Ovalbumin (Ova) challenge on days 24 and 27 to generate an in vivo asthma model. Tc extract (hydroalcoholic, 100 mg/kg) and dexamethasone (1 mg/kg) were given orally from day 15 to 23 to the Tc+Ova treated group and Dex+Ova treated group respectively. Oxidative stress parameters e.g. activity of superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx) and catalase, lipid peroxidation, GSH/GSSG ratio, protein carbonyl content, eosinophil peroxidase, myeloperoxidase activity, and NO release were measured in tissue, blood and bronchoalveolar lavage fluid (BALF). Estimation of cytokines was done in BALF. Western blot analysis was done for IκB α, iNOS, COX-2, iCAM-1 and pJNK MAPKs along with histopathology.

RESULTS

Tc extract treated mice showed decreased airway hyper-responsiveness, eosinophil count and IgE content in blood as compared to Ova treated asthmatic mice. Increase in activities of SOD, catalase, glutathione reductase, glutathione peroxidase as well as GSH/GSSG ratio was observed while a decrease in MDA formation, protein carbonyl content, eosinophil peroxidase, myeloperoxidase activity and NO release in BALF was seen in Tc treated mice. In BALF, levels of cytokines IL-4 and TNF-α were reduced and IFN-γ levels increased in extract treated mice. At the same time Tc treatment of Ova-challenged mice significantly increased the level of IκB α, cytosolic inhibitor of redox sensitive transcription factor NFκB. Immunoblot analysis revealed considerable decrease in the levels of COX-2, ICAM-1, iNOS, and pJNK. Histopathology and PAS staining also indicate a protective effect of Tc extract in inflammation and mucus hyper-secretion due to goblet cell hyperplasia.

CONCLUSION

The results suggest a protective effect of Tc extract against oxidative stress, pro-inflammatory mediator release and redox signaling in the murine model of asthma. The Tc extract shows therapeutic potential for management of asthmatic inflammation and other lung inflammatory conditions.

Pinellia ternata Breitenbach attenuates ovalbumin-induced allergic airway inflammation and mucus secretion in a murine model of asthma

OBJECTIVE

Pinellia ternata is an important plant in traditional Chinese medicine. This study describes the anti-inflammatory effects of a water extract of P. ternata (PTE) in allergic airway inflammation in a model of asthma in mice.

MATERIALS AND METHODS

BALB/c mice were sensitized with ovalbumin (OVA) and, upon an OVA aerosol challenge, developed airway eosinophilia, mucus hypersecretion, elevations in cytokine, chemokine, and immunoglobulin levels and overexpression of inducible nitric oxide (iNOS).

RESULTS

Intragastric administration of PTE significantly attenuated OVA-induced influx of total leukocytes, eosinophils, neutrophils, macrophages and lymphocytes into lungs, and attenuated levels of interleukin (IL)-4, IL-13 and tumor necrosis factor-α (TNF-α), in a dose-dependent manner. PTE also significantly reduced the plasma levels of total and OVA-specific immunoglobulin (Ig)E release into the airspace. Histological studies showed that PTE inhibited OVA-induced lung tissue eosinophilia and airway mucus production. Moreover, in whole lung tissue lysates, immunohistology showed that PTE markedly attenuated the OVA-induced increase in mucin 5AC and iNOS expression.

CONCLUSIONS

These results indicate that PTE has protective effects against allergic airway inflammation.

Anti-inflammatory effects of ethanolic extract from Lagerstroemia indica on airway inflammation in mice

AIM OF THE STUDY

In the present study, we investigated whether the Lagerstroemia indica Linn (LI) extract has an anti-inflammatory effect on lung inflammation in ovalbumin-induced asthmatic mice.

MATERIALS AND METHODS

The LI extract was obtained from dried and powdered whole plants of LI using 80% ethanol. ELISA was performed to evaluate cytokine concentration. BALB/c mice were used as a mouse model of asthma after asthmatic induction by ovalbumin sensitization and inhalation. We examined the effects of the LI extract on leukocyte infiltration and mucus secretion using cell count and histological stain.

RESULTS

The amount of cytokines, such as interleukin (IL)-2, IL-4, IL-5, IL-13, and TNF-α, was increased in Jurkat cells using the extract from house dust mites. Increased cytokine concentrations were inhibited by the LI extract. The LI extract suppressed the increased expression of IL-6 after treatment with mite extract of EoL-1 cells and THP-1 cells. In an in vivo experiment using asthmatic mice, the LI extract significantly inhibited leukocytosis and eosinophilia in bronchoalveolar lavage (BAL) fluid and lung tissue samples. The LI extract inhibited the increase in mucus secretion by goblet cells, blocked the production of reactive oxygen species in BAL fluid cells, and blocked the protein expression of IL-5 in BAL fluid. The concentration of ovalbumin-specific IgE in BAL fluid was weakly inhibited by the LI extract.

CONCLUSIONS

These results suggest that the LI extract may be used as a valuable agent for treating allergic diseases such as asthma due to its anti-inflammatory property.

Anti-inflammatory, immunomodulatory, and heme oxygenase-1 inhibitory activities of ravan napas, a formulation of uighur traditional medicine, in a rat model of allergic asthma

Ravan Napas (RN) is a traditional formula used to treat pulmonary symptoms and diseases such as coughing, breathing difficulty, and asthma in traditional Uighur medicine. The purpose of this study was to investigate the anti-inflammatory, and immuno-modulatory activity of RN in a well-characterized animal model of allergic asthma. Rats were sensitized with intraperitoneal (ip) ovalbumin (OVA) and alum, and then challenged with OVA aerosols. The asthma model rats were treated with RN; saline- and dexamethasone- (DXM-) treated rats served as normal and model controls. The bronchoalveolar lavage fluid (BALF) cellular differential and the concentrations of sICAM-1, IL-4, IL-5, TNF-α, INF-γ, and IgE in serum were measured. Lung sections underwent histological analysis. The immunohistochemistry S-P method was used to measure the expression of ICAM-1 and HO-1 in the lung. RN significantly reduced the number of inflammatory cells in BALF and lung tissues, decreased sICAM-1, IL-4, IL-5, TNF-α, and IgE in serum, and increased serum INF-γ. There was a marked suppression of ICAM-1 and HO-1 expression in the lung. Our results suggest that RN may have an anti-inflammatory and immuneregulatory effect on allergic bronchial asthma by modulating the balance between Th1/Th2 cytokines.