Anti-asthmatic effects of baicalin in a mouse model of allergic asthma

Sanfeng Tongqiao Dripping Pills alleviate House Dust Mite-induced allergic rhinitis in mice by inhibiting Th2 differentiation and repairing the nasal epithelial barrier

BACKGROUND

Sanfeng Tongqiao Dripping Pills (SFTQ) has clinically demonstrated a promising therapeutic effect on allergic rhinitis (AR). However, the active ingredients and underlying mechanisms of SFTQ remain unclear.

PURPOSE

Exploring the effects, mechanisms, and active ingredients of SFTQ in the treatment of AR is valuable.

STUDY DESIGN

The mechanisms of SFTQ and its active ingredients in treating AR were investigated through in vivo and in vitro studies.

METHODS

A HDM-induced AR model was established in BALB/c mice. The effects of SFTQ in treating AR were evaluated by AR-like symptoms, EOS count, and pathological changes in the nasal tissue in vivo. The effects of SFTQ active components on epithelial cells (ECs) were evaluated in Poly(I:C) and TNF-α co-stimulated human nasal ECs (RPMI-2650). Additionally, the effects of SFTQ active components on splenocytes proliferation and Th cell differentiation were assessed. A co-culture system of ECs and T lymphocytes was established to investigate the impact of Th2 cells on the structure and function of ECs. The effects of SFTQ ingredients on ECs, T lymphocytes, and the HDM-induced AR model were further confirmed through in vivo and in vivo studies, respectively.

RESULTS

SFTQ significantly alleviated AR-like symptoms and pathological changes in the nasal tissue of AR mice. The treatment elevated the expression of Occludin and E-cadherin in the nasal epithelium and reduced the percentage of Th2 cells in cervical lymph nodes (CLN). Among the active compounds of SFTQ, L-Menthone and Pulegone notably downregulated IL-33 levels in activated ECs, while Hesperetin significantly decreased TSLP and IL-33 levels. In the co-culture system of ECs and Th2 cells, exposure to Baicalin, Wogonin, and Pulegone increased the TEER value of ECs, while notably inhibiting the production of TSLP and IL-33. Furthermore, in HDM-induced AR mice, treatments with Baicalin, Luteolin, and Hesperetin effectively inhibited AR-like symptoms. Additionally, Luteolin and Hesperetin significantly reduced the inflammatory cells infiltration and the population of Th2 cells in AR mice.

CONCLUSION

SFTQ and its active ingredients effectively alleviated HDM-induced AR in mice by inhibiting Th2 cell differentiation and repairing the nasal epithelial barrier. Our study can provide a scientific basis for SFTQ to be used in clinical treatment of AR.

Wogonoside Ameliorates Airway Inflammation and Mucus Hypersecretion via NF-κB/STAT6 Signaling in Ovalbumin-Induced Murine Acute Asthma

Asthma is recognized as a chronic respiratory illness characterized by airway inflammation and airway hyperresponsiveness. Wogonoside, a flavonoid glycoside, is reported to significantly alleviate the inflammation response and oxidative stress. Herein, this study aimed to investigate the therapeutic effect and underlying mechanism of wogonoside on airway inflammation and mucus hypersecretion in a murine asthma model and in human bronchial epithelial cells (16HBE). BALB/c mice were sensitized and challenged with ovalbumin (OVA). Pulmonary function and the number of cells in the bronchoalveolar lavage fluid (BALF) were examined. Pathological changes in lung tissue in each group were evaluated via hematoxylin and eosin and periodic acid-Schiff staining, and changes in levels of cytokines in BALF and of immunoglobulin E in serum were determined via an enzyme-linked immunosorbent assay. The expression of relevant genes in lung tissue was analyzed via real-time PCR. Western blotting and immunofluorescence were employed to detect the expression of relevant proteins in lung tissue and 16HBE cells. Treatment with 10 and 20 mg/kg wogonoside significantly attenuated the OVA-induced increase of inflammatory cell infiltration, mucus secretion, and goblet cell percentage and improved pulmonary function. Wogonoside treatment reduced the level of T-helper 2 cytokines including interleukin (IL)-4, IL-5, and IL-13 in BALF and of IgE in serum and decreased the mRNA levels of cytokines (IL-4, IL-5, IL-6, IL-13, and IL-1β and tumor necrosis factor-α), chemokines (CCL-2, CCL-11, and CCL-24), and mucoproteins (MUC5AC, MUC5B, and GOB5) in lung tissues. The expression of MUC5AC and the phosphorylation of STAT6 and NF-κB p65 in lung tissues and 16HBE cells were significantly downregulated after wogonoside treatment. Thus, wogonoside treatment may effectively decrease airway inflammation, airway remodeling, and mucus hypersecretion via blocking NF-κB/STAT6 activation.

Preparation and in vivo evaluation of nano sized cubosomal dispersion loaded with Ruta graveolens extracts as a novel approach to reduce asthma-mediated lung inflammation

Asthma is a chronic disease affecting people of all ages. Asthma medications are associated with adverse effects restricting their long-term usage, demanding newer alternative therapies. This study aimed to investigate the anti-asthmatic properties of Ruta graveolens extract and its prepared nano-cubosomal dispersion (Ruta-ND). Firstly, the R. graveolens methanolic extract exhibited higher anti-inflammatory activity on Lipopolysaccharide (LPS)-activated BEAS-2B cells. To ensure best bioavailability and hence best cellular uptake, R. graveolens extract was loaded in nano-cubosomal dispersion (ND). Then, the anti-asthmatic effects of Ruta extract and ND were simultaneously evaluated in rats' model with ovalbumin-induced allergic asthma. R. graveolens extract and Ruta-ND subsided asthma score and improved lung function by restoring FEV1/FVC ratio to the expected values in control rats. Also, it showed strong antioxidant and anti-inflammatory activities manifested by lowering levels of malondialdehyde (MDA), IL-4, IL-7, TGF-β, and Ig-E, and increasing levels of superoxide dismutase (SOD) and INF-γ in bronchoalveolar lavage fluid. Our research findings also indicate autophagy induction and apoptosis inhibition by Ruta extract and Ruta-ND. Finally, the HPLC MS/MS phytochemical profiling of R. graveolens extract evident production of various alkaloids, flavonoids, coumarins, and other phenolics with reported pharmacological properties corresponding to/emphasize our study findings. In conclusion, R. graveolens exhibited promise in managing Ova-induced allergic asthma and could be developed as an alternative anti-allergic asthma drug.

The protective effects of baicalin for respiratory diseases: an update and future perspectives

Background: Respiratory diseases are common and frequent diseases. Due to the high pathogenicity and side effects of respiratory diseases, the discovery of new strategies for drug treatment is a hot area of research. Scutellaria baicalensis Georgi (SBG) has been used as a medicinal herb in China for over 2000 years. Baicalin (BA) is a flavonoid active ingredient extracted from SBG that BA has been found to exert various pharmacological effects against respiratory diseases. However, there is no comprehensive review of the mechanism of the effects of BA in treating respiratory diseases. This review aims to summarize the current pharmacokinetics of BA, baicalin-loaded nano-delivery system, and its molecular mechanisms and therapeutical effects for treating respiratory diseases.

Method: This review reviewed databases such as PubMed, NCBI, and Web of Science from their inception to 13 December 2022, in which literature was related to “baicalin”, “Scutellaria baicalensis Georgi”, “COVID-19”, “acute lung injury”, “pulmonary arterial hypertension”, “asthma”, “chronic obstructive pulmonary disease”, “pulmonary fibrosis”, “lung cancer”, “pharmacokinetics”, “liposomes”, “nano-emulsions”, “micelles”, “phospholipid complexes”, “solid dispersions”, “inclusion complexes”, and other terms.

Result: The pharmacokinetics of BA involves mainly gastrointestinal hydrolysis, the enteroglycoside cycle, multiple metabolic pathways, and excretion in bile and urine. Due to the poor bioavailability and solubility of BA, liposomes, nano-emulsions, micelles, phospholipid complexes, solid dispersions, and inclusion complexes of BA have been developed to improve its bioavailability, lung targeting, and solubility. BA exerts potent effects mainly by mediating upstream oxidative stress, inflammation, apoptosis, and immune response pathways. It regulates are the NF-κB, PI3K/AKT, TGF-β/Smad, Nrf2/HO-1, and ERK/GSK3β pathways.

Conclusion: This review presents comprehensive information on BA about pharmacokinetics, baicalin-loaded nano-delivery system, and its therapeutic effects and potential pharmacological mechanisms in respiratory diseases. The available studies suggest that BA has excellent possible treatment of respiratory diseases and is worthy of further investigation and development.

Pharmacological effects of baicalin in lung diseases

The flavonoids baicalin and baicalein were discovered in the root of Scutellaria baicalensis Georgi and are primarily used in traditional Chinese medicine, herbal supplements and healthcare. Recently, accumulated investigations have demonstrated the therapeutic benefits of baicalin in treating various lung diseases due to its antioxidant, anti-inflammatory, immunomodulatory, antiapoptotic, anticancer, and antiviral effects. In this review, the PubMed database and ClinicalTrials website were searched with the search string "baicalin" and "lung" for articles published between September 1970 and March 2023. We summarized the therapeutic role that baicalin plays in a variety of lung diseases, such as chronic obstructive pulmonary disease, asthma, pulmonary fibrosis, pulmonary hypertension, pulmonary infections, acute lung injury/acute respiratory distress syndrome, and lung cancer. We also discussed the underlying mechanisms of baicalin targeting in these lung diseases.

Modified BuShenYiQi formula alleviates experimental allergic asthma in mice by negative regulation of type 2 innate lymphoid cells and CD4+ type 9 helper T cells and the VIP-VPAC2 signalling pathway

CONTEXT

Modified BuShenYiQi formula (M-BYF) is derived from BuShenYiQi formula, used for the treatment of allergic asthma. The exact effect and mechanism of M-BYF on the improvement of asthma remain unclear.

OBJECTIVE

We investigated the mechanism underlying the therapeutic effect of M-BYF on allergic asthma.

MATERIALS AND METHODS

The asthma model was established in female BALB/c mice that were sensitized and challenged with ovalbumin (OVA). Mice in the treated groups were orally treated once a day with M-BYF (7, 14 and 28 g/kg/d) or dexamethasone before OVA challenge. Control and Model group received saline. Pathophysiological abnormalities and percentages of lung type 2 innate lymphoid cells (ILC2s) and Th9 cells were measured. Expression levels of type 2 cytokines and transcription factors required for these cells function and differentiation were analysed. Expression of vasoactive intestinal polypeptide (VIP)-VPAC2 signalling pathway-related proteins, and percentages of VIP expressing (VIP⁺) cells and VPAC2, CD90 co-expressing (VPAC2⁺CD90⁺) cells were detected.

RESULTS

M-BYF alleviated airway hyperresponsiveness, inflammation, mucus hypersecretion and collagen deposition in asthmatic mice. M-BYF down-regulated percentages of ILC2s and Th9 cells with lower expression of GATA3, PU.1 and IRF4, reduced IL-5, IL-13, IL-9 and VIP production. The decrease in the expression of VIP-VPAC2 signalling pathway and percentages of VIP⁺ cells, VPAC2⁺CD90⁺ cells were observed after M-BYF treatment. The LD₅₀ value of M-BYF was higher than 90 g/kg.

DISCUSSION AND CONCLUSIONS

M-BYF alleviated experimental asthma by negatively regulating ILC2s and Th9 cells and the VIP-VPAC2 signalling pathway. These findings provide the theoretical basis for future research of M-BYF in asthma patient population.

Polyphenols affect the humoral response in cancer, infectious and allergic diseases and autoimmunity by modulating the activity of TH1 and TH2 cells

Polyphenols are a wide class of natural substances, pleiotropic molecules capable of modulating several processes, involved in the humoral and cellular immune response. The activation, differentiation of B cells, and production of antibodies to protein antigens by plasma cells depend on T helper (T_H) CD4⁺ cells and secreted cytokines. Cancer, infectious, allergic, and autoimmune diseases are characterized by an imbalance of T_H1/T_H2 immunity and abnormal activation of the humoral response. Accordingly, polyphenols modulate the T_H1/T_H2 ratio, the secretion of multiple cytokines, the levels of antibodies, and therefore could contribute to recovering the state of health in these diseases. In this review, we summarize the current knowledge on the effects of polyphenols in modulating the humoral response in cancer, infectious and allergic diseases and in autoimmunity by affecting the activity of T_H1 and T_H2 cells.

Protective effect of Asarum sieboldii essential oil on ovalbumin induced allergic rhinitis in rat

BACKGROUND

The study was aimed to investigate the protective effect of Asarum sieboldii Miq. essential oil (AEO) on ovalbumin (OVA)-induced allergic rhinitis (AR) in rats.

METHODS AND RESULTS

Sixty Sprague-Dawley male rats were randomly divided into six groups (n=10): control, model, cetirizine (Cet, 4.65 g/kg), and AEO (0.5, 1.5, 3 g/kg) groups. All animals except the control group received repeated intranasal instillation with 20 μl of 20% OVA in Al(OH)3 saline solvent for 15 days. The control group was intranasally instilled with 5 mg/ml of Al(OH)3 instead of the same procedure. In the 15 days, Cet and AEO were orally administrated for 28 days. At the end of the drug administration, 20 μl of 5% OVA was given to animals to stimulate allergic reaction, then the rat behavioral detection, assessment of the patho-morphological changes in nasal mucosa, and the serum biomarkers were determined. The result showed that AEO could significantly reduce the amount of nasal secretions, sneezing, and the degree of nasal scratching in AR rats with EC50 = 1.5 and 2.8 g/kg, respectively. The degree of nasal mucosal inflammation in AEO group improved, the levels of immunoglobulin E (IgE), histamine, IL-4, IL-5, IL-17 were decreased, and the level of IFN-γ was increased obviously with EC50 = 2 g/kg.

CONCLUSION

The study suggested that the possible mechanism might be related with the inhibition of histamine release and regulation of the cytokine levels, which plays an important role in the treatment of AR.

Baicalin regulates the development of pediatric asthma via upregulating microRNA-103 and mediating the TLR4/NF-κB pathway

Pediatric asthma seriously endangers the well-being and health of children worldwide. Baicalin (BA) protects against diverse disorders, including asthma. Therefore, this study explored the mechanism of BA in pediatric asthma. The ovalbumin (OVA)-induced asthmatic mouse model was established to evaluate BA efficacy from aspects of oxidative stress, inflammation, blood cells in bronchoalveolar lavage fluid (BALF) and collagen deposition. Differentially expressed microRNAs (miRs) in BA-treated mice were analyzed. Effects of BA on PDGF-BB-induced smooth muscle cells (SMCs) were assessed. miR downstream mRNA and the related pathway were predicted and verified, and their effects on asthmatic mice were evaluated. BA effectively reversed OVA-induced oxidative stress and inflammation, as well as decreased the number of total cells, eosinophils and neutrophils in BALF, and collagen deposition. miR-103 was significantly upregulated after BA treatment. BA inhibited the abnormal proliferation of PDGF-BB-induced SMCs, which was prevented by miR-103 knockdown. miR-103 targeted TLR4 and regulated the extent of NF-κB phosphorylation. In vivo, miR-103 inhibition weakened the alleviating effects of BA on asthma, which was then reversed after silencing of TLR4. We highlighted that BA has the potency to halt the pediatric asthma progression via miR-103 upregulation and the TLR4/NF-κB axis inhibition.

Baicalin suppresses type 2 immunity through breaking off the interplay between mast cell and airway epithelial cell

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Japanese herbal medicine Shin'iseihaito was reported to ameliorate the airway type 2 inflammatory response in clinical and experimental studies. Airway type 2 inflammatory diseases, including bronchial asthma and eosinophilic chronic rhinosinusitis (ECRS), often coexist and interact with each other. However, it is still unclear how Shin'iseihaito exerts its pharmacological effects on cells involved in airway mucosa.

AIM OF THE STUDY

This study aims to examine the direct effect of baicalin, a representative bioactive compound of Shin'iseihaito, on type 2 immune responses in human airway epithelial cells and mast cells.

MATERIAL AND METHODS

We measured the plasma pharmacokinetics of flavonoids derived from Shin'iseihaito and investigated the effects of baicalin on type 2 immune responses in human airway epithelial cells and human mast cells.

RESULTS

Baicalin, wogonin, and wogonoside were detected in the plasma. The maximum plasma concentration of baicalin was highest at 1610 ng/ml (3.6 μM). In the normal human bronchial epithelial cells treated with baicalin, with or without stimulation by IFN-γ, the IL-33 expression was significantly downregulated. However, baicalin treatment did not affect the levels of thymic stromal lymphopoietin and IL-25. We noted that IL-33-dependent expression of tryptase mRNA in mast cells was significantly inhibited by baicalin. Also, the expression of IL-5 in mast cells enhanced by stimulation with TSLP plus IL-1β was significantly downregulated by baicalin treatment. Moreover, the enhancement of IL-13 expression in mast cells by IL-33 simulation was also significantly inhibited by baicalin.

CONCLUSIONS

Our results prove that by breaking off the vicious circle of mast cells and airway epithelial cells, baicalin may be an effective alternative therapeutic option for the treatment of type 2 inflammatory diseases, such as ECRS and comorbid asthma.

Active ingredients from Chinese medicine plants as therapeutic strategies for asthma: Overview and challenges

Although considerable advance has been made in diagnosing and treating, asthma is still a serious public health challenge. Traditional Chinese medicine (TCM) is an effective therapy of complementary and alternative medicine. More and more scientific evidences support the use of TCM for asthma treatment, and active ingredients from Chinese medicine plants are becoming a hot issue.

PURPOSE OF REVIEW

To summarize the frontier knowledge on the function and underlying mechanisms of the active ingredients in asthma treatments and provide a fully integrated, reliable reference for exploring innovative treatments for asthma.

METHODS

The cited literature was obtained from the PubMed and CNIK databases (up to September 2020). Experimental studies on the active ingredients of Chinese medicine and their therapeutic mechanisms were identified. The key words used in the literature retrieval were "asthma" and "traditional Chinese medicine" or "Chinese herbal medicine". The literature on the active ingredients was then screened manually.

RESULTS

We summarized the effect of these active ingredients on asthma, primarily including the effect through which these ingredients can regulate the immunologic equilibrium mechanism by acting on a number of signalling pathways, such as Notch, JAK-STAT-MAPK, adiponectin-iNOS-NF-κB, PGD2-CRTH2, PI3K/AKT, Keap1-Nrf2/HO-1, T-bet/Gata-3 and Foxp3-RORγt, thereby regulating the progression of asthma.

CONCLUSION

The active ingredients from Chinese medicine have multilevel effects on asthma by regulating the immunologic equilibrium mechanism or signalling pathways, giving them great clinical value. However, the safety and functional mechanism of these ingredients still must be further determined.

Present Status and Future Trends of Natural-Derived Compounds Targeting T Helper (Th) 17 and Microsomal Prostaglandin E Synthase-1 (mPGES-1) as Alternative Therapies for Autoimmune and Inflammatory-Based Diseases

Several natural-based compounds and products are reported to possess anti-inflammatory and immunomodulatory activity both in vitro and in vivo. The primary target for these activities is the inhibition of eicosanoid-generating enzymes, including phospholipase A2, cyclooxygenases (COXs), and lipoxygenases, leading to reduced prostanoids and leukotrienes. Other mechanisms include modulation of protein kinases and activation of transcriptases. However, only a limited number of studies and reviews highlight the potential modulation of the coupling enzymatic pathway COX-2/mPGES-1 and Th17/Treg circulating cells. Here, we provide a brief overview of natural products/compounds, currently included in the Italian list of botanicals and the BELFRIT, in different fields of interest such as inflammation and immunity. In this context, we focus our opinion on novel therapeutic targets such as COX-2/mPGES-1 coupling enzymes and Th17/Treg circulating repertoire. This paper is dedicated to the scientific career of Professor Nicola Mascolo for his profound dedication to the study of natural compounds.

Baicalin suppresses Th1 and Th17 responses and promotes Treg response to ameliorate sepsis-associated pancreatic injury via the RhoA-ROCK pathway

Recent studies have reported that the imbalance of T helper 1 cell (Th1), Th17 and regulatory T cell (Treg) have been confirmed to play a vital role in the development of sepsis and other inflammatory diseases. Baicalin (BA) has anti-inflammatory properties and improves survival in sepsis. We investigated whether baicalin could regulate Th1, Th17 and Treg responses to ameliorate sepsis-associated pancreatic injury through the ras homolog family member A (RhoA)-Rho kinase (ROCK) pathway. The sepsis model was established by using the cecal ligation and puncture (CLP) method. Fifty mice were randomly divided into five groups (n = 10): sham group, model group, low-dose group (BA-L, 100 mg/kg of baicalin), medium-dose group (BA-M, 200 mg/kg of baicalin) and highdose group (BA-H, 300 mg/kg of baicalin). The effects of baicalin on the pancreatic injury, on changes of Th1, Th17 and Treg cells in vivo and in vitro, on RhoA, ROCK1 and signal transducer and activator of transcription (STAT) signaling pathways, and on levels of interferon-γ (IFN-γ), interleukin-17 (IL-17) and IL-10 were examined. Treatment of the CLP mice with baicalin significantly reduced the extent, scope and severity of the pathological changes of sepsis-associated pancreatic injury. Baicalin evidently reduced Th1 and Th17 cells and increased Treg cells in peripheral blood, spleen, pancreatic tissue and significantly inhibited T-box protein expressed in T cells (T-bet), retinoic acid receptor-related orphan receptor γt (RORγt) and increased forkhead/winged helix transcription factor (Foxp3) expressions in the pancreatic tissue. Baicalin reduced the expressions of RhoA, ROCK1, phosphorylated STAT4 (p-STAT4), p-STAT3 and increased the expression of p-STAT5 in peripheral blood, spleen and pancreatic tissue. Baicalin reduced the expressions of IFN-γ and IL-17 and increased the IL-10 in serum and pancreatic tissue. Baicalin is capable of ameliorating sepsis-associated pancreatic injury and regulating Th1, Th17 and Treg responses in sepsis. The present study provided a potential adjunctive therapy for treating pancreatic injury in sepsis, and further study is needed to reveal its deeper mechanisms.

Mangiferin suppresses allergic asthma symptoms by decreased Th9 and Th17 responses and increased Treg response

Mangiferin is the major bioactive ingredient in the leaves of Mangifera indica L., Aqueous extract of such leaves have been traditionally used as an indigenous remedy for respiratory diseases including cough and asthma in Traditional Chinese Medicine. Mangiferin was shown to exert its anti-asthmatic effect by modulating Th1/Th2 cytokines imbalance via STAT6 signaling pathway. However, compelling evidence indicated that subtypes of T helpers and regulatory T cells other than Th1/Th2 were also involved in the pathogenesis of asthma. In current study, we investigated the effects of mangiferin on the differentiation and function of Th9, Th17 and Treg cells in a chicken egg ovalbumin (OVA)-induced asthmatic mouse model. Mangiferin significantly attenuated the symptoms of asthma attacks, reduced the total number of leukocytes, EOS and goblet cells infiltration in lung. Simultaneously, treatment with mangiferin remarkably decreased the proportion of Th9 and Th17 cells; reduced the levels of IL-9, IL-17A; inhibited the expression of PU.1 and RORγt in lung. However, the proportion of Treg cells, the expression of IL-10, TGF-β1 and Foxp3 were increased by mangiferin. Our data suggest that mangiferin exerted anti-asthmatic effect through decreasing Th9 and Th17 responses and increasing Treg response in OVA-induced asthmatic mouse model.

Protective Effects of Baicalin on Experimental Myocardial Infarction in Rats

Objective

This study aimed to investigate the protective effects of baicalin on myocardial infarction in rats and explore the related mechanisms.

Methods

Fifty Sprague Dawley rats were randomly divided into the control, model, and low-, medium- and high-dose baicalin groups. The latter 3 groups were intraperitoneally injected with baicalin, with a dose of 12.5, 25 and 50 mg/kg, respectively. Then, the myocardial infarction model was established. The hemodynamic of rats was tested, the serum lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), prostacyclin (PGI₂) and thromboxane A₂ (TXA₂) were determined, the myocardial superoxide dismutase (SOD) and malondialdehyde (MDA) levels were detected, and the myocardial B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X (Bax) protein expressions were determined.

Results

Compared with the model group, in the high-dose baicalin group the ST segment height and LVEDP were significantly decreased (P<0.05), the LVSP was significantly increased (P<0.05), the serum LDH, CK-MB and TXA2 levels were significantly decreased (P<0.05), the PGI₂ level was significantly increased (P<0.05), the myocardial SOD level was significantly increased (P<0.05), and the myocardial MDA level was significantly decreased (P<0.05); the myocardial Bcl-2 protein level was significantly increased, and the Bax protein level was significantly decreased (P<0.05).

Conclusion

Baicalin has protective effects on myocardial infarction in rats. The possible mechanisms may be related to its resistance to oxidative stress, and up-regulation of Bcl-2 protein expression and down-regulation of Bax protein expression in myocardial tissue.

Baicalin inhibits IgG production by regulating Treg/Th17 axis in a mouse model of red blood cell transfusion

This study was conducted to evaluate whether baicalin inhibits red blood cell (RBC) immunization and elucidate the underlying mechanism. We used human RBCs with adjuvant lipopolysaccharide (LPS) and transfused mice to induce antibodies as an experimental system for studying the effect of baicalin on RBC immunization. Mice were divided into a human RBC transfused positive control group administered with human RBC and LPS intravenously once or weekly for 4 weeks, control group administered dexamethasone (DEX) intraperitoneally daily for 4 weeks, and treatment group administered baicalin intraperitoneally daily for 4 weeks. Assessment of human RBC immunization was performed by measuring serum immunoglobulin G (IgG) and immunoglobulin M (IgM) against human RBC weekly. Lymphocyte changes in spleen were monitored by flow cytometry. We found that baicalin treatment significantly decreased serum IgG but not IgM production in a time and does dependent manner, with a concomitant reduction in Th17 cells and increase in CD4 regulatory T cells in the spleen. The percentage of CD4-positive cells in the spleen was not decreased in the baicalin-treated group but was decreased in the dexamethasone-treated group. In conclusion, baicalin inhibited RBC immunization, particularly IgG production by regulating the Treg/Th17 axis without damaging spleen function.

Metabolic profiling of endogenous bile acids: a novel method to assess hepatoprotective effect of Tanreqing capsule on carbon-tetrachloride-induced liver injury in rats

Tanreqing (TRQ), a traditional Chinese medicine (TCM) formula, can alleviate liver injury and improve liver function. Its pharmacological mechanisms of actions are still unclear due to its complex components and multi-target natures. Metabolomic study is an effective approach to investigating drug pharmacological actions, new diagnostic markers, and potential mechanisms of actions. In the present study, a new strategy was used to evaluate the protective effect of TRQ capsule against carbon tetrachloride (CCl₄)-induced hepatotoxicity in rats, by analyzing metabolic profiling of endogenous bile acids (BAs) along with biochemical and histological analyses. BAs concentrations were determined by ultra-performance liquid chromatography coupled with quadrupole mass spectrometry (UPLC-MS). Principal component analysis and partial least squares discriminant analysis were then employed to analyze the UPLC-MS results and compare the hepatoprotective effect of TRQ capsule in different groups at the doses of 0.36, 1.44, and 2.88 g·kg^-1 body weight, respectively. Moreover, our results suggested that taurocholic acid (TCA) and taurohyodesoxycholic acid (THDCA) were the most important biochemical markers, which were indicative of CCl₄-induced acute hepatic damage and hepatoprotective effect of TRQ capsule. Therefore, this new strategy would be an excellent alternative method for evaluating hepatoprotective effect and proposing potential mechanisms of action for other drugs as well.

Flavonoids as Th1/Th2 cytokines immunomodulators: A systematic review of studies on animal models

BACKGROUND

Flavonoids are naturally occurring compounds, extensively distributed in plants. T helper (Th)1 and Th2 cytokines balance plays an essential role in the reaction of inflammatory, allergic and infectious processes and transplantation rejection.

PURPOSE

This systematic review focuses on various classes of flavonoids with a view to evaluate whether Th1/Th2 cytokine-mediated pathways of immunoenhancement could reduce immune overwhelming reactions.

METHODS

Articles in English published from inception to December 2017 reporting flavonoids with immunomodulatory activity for the management of immune-mediated disorders were acquired from PubMed, EMBASE, Scopus and Web of Science and a animal experiments where Th1 and Th2 cytokines were investigated to assess the outcome of immunoregulatory therapy were included.

CHAPTERS

1809 publications were identified and 26 were included in this review. Ten articles described the effect of flavonoids on allergic inflammation in an animal model of asthma; eleven in vivo studies evaluated the immunomodulating and immunosuppressive effects of flavonoids on Th1/Th2 cytokines production and five reports described the regulatory role of flavonoids for Th1/Th2 cytokine responses to experimental arthritis and myocarditis. Modulation of Th1/Th2 cytokine balance, inhibition of eosinophil accumulation and remodeling of the airways and lungs, downregulation of Notch and PI3K signaling pathways, regulation of CD4 + /CD8 + lymphocytes ratio and decreasing inflammatory mediator expressions levels are among the most important immunopharmacological mechanisms for the retrieved flavonoids.

CONCLUSION

Naturally occurring flavonoids discussed in the present article have optimal immunomodulation to prevent immune-mediated disorders through management of Th1/Th2 cytokine balance.

Bioactive compounds of Shuang-Huang-Lian prescription and an insight into its binding mechanism by β2 -adrenoceptor chromatography coupled with site-directed molecular docking

Owing to the promising clinical efficacy and relatively simple composition, Shuang-Huang-Lian prescription is widely prescribed for the treatment of acute upper respiratory tract infection and acute bronchitis in practice. This necessitates the understanding of the bioactive compounds of the prescription and their binding mechanism to β₂ -adrenoceptor, which mediates the aforementioned ailments. In this work, a column containing immobilized β₂ -adrenoceptor was prepared using a diazonium salt reaction. The bioactive compound collected from the β₂ -adrenoceptor column was identified as chlorogenic acid by using high-performance liquid chromatography coupled with ion trap mass spectrometry. Using an injection amount dependent method, chlorogenic acid proved the binding to β₂ -adrenoceptor through two kinds of sites. The numbers of the sites were (1.42 ± 0.03) × 10^-8 and (9.06 ± 0.49) × 10^-8  M. The association constants were (2.72 ± 0.01) × 10⁵ and (2.80 ± 0.01) × 10⁴  M^-1 , respectively. Molecular docking analysis of the interaction between chlorogenic acid and β₂ -adrenoceptor indicated that the binding mainly occurred on Ser¹⁶⁹ , Ser¹⁷³ , and Phe²⁸⁷ of β₂ -adrenoceptor. These results paved the way to screen bioactive compounds of other traditional medicines by receptor chromatography.

Regulatory effect of baicalin on the imbalance of Th17/Treg responses in mice with allergic asthma

ETHNOPHARMACOLOGY RELEVANCE

Baicalin, a flavonoid compound, was isolated from traditional Chinese medicine Scutellaria baicalensis Georgi. The study aimed to explore the regulatory effect of baicalin on immunological balance of Th17/Treg responses and the possible mechanisms in mice with allergic asthma.

MATERIALS AND METHODS

Mice were sensitized and challenged with OVA+LPS by intranasal instillation, and were intragastrically treated with baicalin from days 22-36 after sensitization. The organ coefficient of lung was determined. Immunoglobulin E (IgE) level in serum and cytokine IL-17A, IL-6, IL-10 levels in bronchoalveolar lavage fluid (BALF) were measured by ELISA. Histological changes in lung and airway tissues were observed by hematoxylin and eosin (H&E) and periodic acid-Schiff staining (PAS). The expressions of signal transducer and activator of transcription 3 (STAT3) and forkhead box P3 (FOXP3) in lung tissues were evaluated by immunohistochemistry and western blot methods.

RESULTS

Baicalin obviously decreased OVA+LPS-induced organ coefficient of lung, inhibited serum IgE and BALF IL-7A and IL-6 secrection, promoted BALF IL-10 secrection in a dose-dependent manner. Histological studies demonstrated that baicalin significantly alleviated OVA+LPS-induced inflammatory responses and mucus secretion in lung and airway tissues. Immunohistochemistry and western blot studies showed that baicalin substantially suppressed STAT3 expression and promoted FOXP3 expression in lung tissues of mice.

CONCLUSIONS

These findings suggest that baicalin effectively protects against OVA+LPS-induced allergic asthma in mice by regulating the immunological imbalance of Th17/Treg responses.

Discovery of a novel series of α-terpineol derivatives as promising anti-asthmatic agents: Their design, synthesis, and biological evaluation

A series of novel α-terpineol derivatives were designed and synthesized through structural derivatization of the tertiary hydroxyl moiety or reduction of the double bond. Of the resulting compounds, eight compounds enhanced relaxation of airway smooth muscle (ASM) compared to the α-terpineol precursor, and four compounds (4a, 4d, 4e, and 4i)were superior or comparable to aminophylline at a concentration of 0.75 mmol/L. Assays for 3'-5'-Cyclic adenosine monophpsphate (cAMP) activation revealed that some representative α-terpineol derivatives in this series were capable of upregulating the level of cAMP in ASM cells. Further in vivo investigation using the asthmatic rat model, illustrated that treatment with the compounds 4a and 4e resulted in significantly lowered lung resistance (RL) and enhanced dynamic lung compliance (Cldyn), two important parameters for lung fuction. Moreover, treatment with 4e downregulated the levels of both IL-4 and IL-17. Due to its several favorable physiological functions, including ASM relaxation activity, cAMP activation capability, and in vivo anti-asthmatic efficacy, 4e is a promising remedy for bronchial asthma, meriting extensive development.

Baicalin inhibits biofilm formation, attenuates the quorum sensing-controlled virulence and enhances Pseudomonas aeruginosa clearance in a mouse peritoneal implant infection model

The quorum sensing (QS) circuit plays a role in the precise regulation of genes controlling virulence factors and biofilm formation in Pseudomonas aeruginosa. QS-controlled biofilm formation by Pseudomonas aeruginosa in clinical settings has remained controversial due to emerging drug resistance; therefore, screening diverse compounds for anti-biofilm or anti-QS activities is important. This study demonstrates the ability of sub-minimum inhibitory concentrations (sub-MICs) of baicalin, an active natural compound extracted from the traditional Chinese medicinal Scutellaria baicalensis, to inhibit the formation of Pseudomonas aeruginosa biofilms and enhance the bactericidal effects of various conventional antibiotics in vitro. In addition, baicalin exerted dose-dependent inhibitory effects on virulence phenotypes (LasA protease, LasB elastase, pyocyanin, rhamnolipid, motilities and exotoxin A) regulated by QS in Pseudomonas aeruginosa. Moreover, the expression levels of QS-regulatory genes, including lasI, lasR, rhlI, rhlR, pqsR and pqsA, were repressed after sub-MIC baicalin treatment, resulting in significant decreases in the QS signaling molecules 3-oxo-C12-HSL and C4-HSL, confirming the ability of baicalin-mediated QS inhibition to alter gene and protein expression. In vivo experiments indicated that baicalin treatment reduces Pseudomonas aeruginosa pathogenicity in Caenorhabditis elegans. Greater worm survival in the baicalin-treated group manifested as an increase in the LT₅₀ from 24 to 96 h. In a mouse peritoneal implant infection model, baicalin treatment enhanced the clearance of Pseudomonas aeruginosa from the implants of mice infected with Pseudomonas aeruginosa compared with the control group. Moreover, the combination of baicalin and antibiotics significantly reduced the numbers of colony-forming units in the implants to a significantly greater degree than antibiotic treatment alone. Pathological and histological analyses revealed mitigation of the inflammatory response and reduced cell infiltration in the peritoneal tissue surrounding the implants after baicalin treatment. Measurement of the cytokine levels in the peritoneal lavage fluid of mice in the baicalin treatment group revealed a decrease in IL-4, an increase in interferon γ (IFN-γ), and a reversed IFN-γ/IL-4 ratio compared with the control group, indicating that baicalin treatment activated the Th1-induced immune response to expedite bacterial load clearance. Based on these results, baicalin might be a potent QS inhibitor and anti-biofilm agent for combating Pseudomonas aeruginosa biofilm-related infections.

Early Postnatal Exposure to Cigarette Smoke Leads to Later Airway Inflammation in Asthmatic Mice

Background and objective

Asthma is one of the most common airway inflammatory diseases. In most cases, asthma development is related to ubiquitous harmful environmental exposure factors in early-life. Previous studies have indicated that smoking can promote asthma development and increase the difficulty of asthma control. The aim of this study was to determine the effects of early-life CS exposure on ovalbumin (OVA)-sensitized asthmatic mice.

Methods

Pathological and immunological functions were analyzed in an adult asthma mice model in which mice were sensitized with OVA combined with early-life CS exposure.

Results

Mice exposed to CS for only 5 weeks demonstrated significantly reduced pulmonary compliance, increased airway inflammation, and augmented cellular and humoral immune responses. In addition, CS inhalation was sufficient to facilitate OVA sensitization and challenge asthmatic development. Meanwhile, CS exposure amplified regulatory T cell-mediated immunity inhibition, but still did not offset the increased effector T cell-mediated inflammatory response.

Conclusion

Early-life CS exposure is significantly associated with later pulmonary injury and aggravation of T-cell immunologic derangement in asthmatic mice.

Esculetin Attenuates Th2 and Th17 Responses in an Ovalbumin-Induced Asthmatic Mouse Model

The purpose of the current study was to investigate the anti-asthmatic effect of esculetin (ES) and explore its potential mechanism with a mouse model of allergic asthma. A total number of 50 mice were randomly assigned to five groups: control, model, dexamethasone (Dex, 2 mg/kg), and ES (20 mg/kg, 40 mg/kg). Mouse asthma model was developed with the sensitization and challenge of ovalbumin (OVA). The levels of IgE in serum, eosinophilia infiltration, Th2/Th17 cytokines, Th17 cell frequency, histological condition, and the protein expressions of RORγt, GATA3 were detected. Our study demonstrated that ES inhibited, OVA-induced eosinophil count, interleukin-4 (IL-4), IL-5, IL-13, and IL-17A levels were recovered in bronchoalveolar lavage fluid. Flow cytometry (FCM) studies revealed that ES substantially inhibited Th17 cells' percentage. Western blot study also indicated that ES downregulated RORγt and GATA3 expressions. Meanwhile, ES had beneficial effects on the histological alteration. These findings suggested that ES might effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma.

Baicalin attenuates inflammation in mice with OVA-induced asthma by inhibiting NF-κB and suppressing CCR7/CCL19/CCL21

Baicalin, extracted and purified from the Chinese medicinal plant, Scutellaria baicalensis Georgi (Huang qin in Chinese), exhibits potent anti-inflammatory activity against asthma. However, it remains unknown whether baicalin inhibits the activity of CC chemokine receptor 7 (CCR7) and its ligands, which are crucial for the initiation of airway inflammation. In the present study, we investigated the effects of baicalin on CCR7 and its ligands, CCL19 and CCL21, as well as on the nuclear factor-κB (NF-κB) pathway in a mouse model of asthma. A mouse model of acute asthma was established by exposing the mice to ovalbumin (OVA) (by intraperitoneal injection and inhalational challenge). Within 24 h of the final OVA challenge, lung function was detected by direct airway resistance analysis. Lung tissues were examined for pathological changes. Inflammatory cell counts in bronchoalveolar lavage fluid (BALF) were assessed. ELISA was utilized to evaluate the OVA-IgE, CCL19 and CCL21 levels in BALF. The interleukin (IL)-6 and tumor necrosis factor (TNF)-α levels in serum were also detected by ELISA. The protein expression levels of CCR7, as well as that of phosphorylated IκBα (p-IκBα) and phosphorylated p65 (p-p65) were determined by western blot analysis and RT-qPCR was used to determine the CCR7 mRNA levels. Our data demonstrated that the oral administration of baicalin significantly improved pulmonary function and attenuated inflammatory cell infiltration into the lungs. Baicalin also decreased the levels of OVA-IgE, IL-6, TNF-α and CCR7, as well as those of its ligand, CCL19; the levels of NF-κB were also markedly suppressed by baicalin. The CCR7 mRNA level was substantially decreased. Our results thus suggest that baicalin exerts an inhibitory effect on airway inflammation, and this effect may be associated with the inhibition of CCR7 and CCL19/CCL21, which may provide new mechanistic insight into the anti‑inflammatory effects of baicalin.

Anti-inflammatory and anti-allergic effects and underlying mechanisms of Huang-Lian-Jie-Du extract: Implication for atopic dermatitis treatment

ETHNOPHARMACOLOGICAL RELEVANCE

Huang-Lian-Jie-Du Decoction (HLJDD), a well-known Chinese herbal formula recorded in the Tang dynasty, is composed of Coptidis rhizoma (Huang-Lian), Scutellariae radix (Huang-Qin), Phellodendri Chinensis cortex (Huang-Bai) and Gardenia fructus (Zhi-Zi). It has clinical efficacy of purging fire for removing toxin and is commonly used for the treatment of disease including Alzheimer's disease, stroke and gastrointestinal disorders. HLJDD is also frequently applied for the treatment of various skin diseases, such as atopic dermatitis (AD) and various types of eczema. The aim of this study is to investigate the anti-inflammatory and anti-allergic actions of Huang-Lian-Jie-Du ethanolic extract (HLJDE) and to elucidate underlying molecular mechanisms of action using relevant in vitro experimental models.

MATERIALS AND METHODS

The anti-inflammatory effects of HLJDE were investigated through evaluating the change of nitric oxide (NO) and the production of several cytokines and chemokines in lipopolysaccharide (LPS)-stimulated RAW264.7 cell line. Expression of mitogen-activated protein kinases (MAPKs), NF-κB p65 phosphorylation, inhibitor-κBα (IκBα) degradation were further investigated to elucidate its anti-inflammatory molecular mechanisms. Meanwhile, the anti-allergic activities of HLJDE was also evaluated using antigen-induced RBL-2H3 cell line. β-hexosaminidase and histamine release and selected cytokines and chemokines were measured to evaluate the anti-allergic activities of HLJDE. In addition, intracellular Ca(2+)level, MAPKs and Lyn phosphorylation were further investigated to reveal its anti-allergic molecular mechanisms.

RESULTS

HLJDE could significantly suppress the secretion of NO, IL-1β, IL-4, MCP-1 and GM-CSF in RAW264.7 cells in a dose-dependent manner. In addition, HLJDE also markedly reduced the phosphorylation of MAPKs, and inhibited the transcriptional activity of NF-κB and IκBα degradation. Furthermore, HLJDE exerted marked anti-allergic activity through inhibiting the release of β-hexosaminidase and histamine. The release of cytokines and chemokines (IL-4, TNF-α, MCP-1) from activated RBL-2H3 cells were also attenuated by pretreatment with HLJDE. The inhibitory effects on intracellular Ca(2+)level, and reduced phosphorylation of MAPKs and Lyn are believed to be the anti-allergic mechanisms.

CONCLUSIONS

HLJDE exerted significant anti-inflammatory and anti-allergic effects through suppressing the production of allergic and inflammatory mediators via the NF-κB and MAPKs inactivation and IκBα degradation in the LPS-stimulated RAW24.7 cells, inactivation of MAPKs and Lyn pathway in antigen-induced RBL-2H3 cells. The present study provides in vitro experimental evidence to support the use of HLJDE for the clinical treatment of AD.

Anti-NDV activity of baicalin from a traditional Chinese medicine in vitro

The purpose of this study was to investigate the anti-Newcastle disease virus (NDV) activities of baicalin from Scutellaria baicalensis, a Traditional Chinese Medicine in vitro. Chicken embryo fibroblasts (CEFs) were infected with NDV, and quantitative analysis of apoptotic cells was performed using flow cytometry. Cytotoxicity and anti-viral activities of baicalin were studied using the MTT method. The results showed that the maximal safe concentrations of baicalin to CEFs was 1 × 2(-2) mg/ml. Baicalin could directly kill NDV, inhibit the infectivity of NDV to CEF and block intracellular NDV. It inhibited the apoptosis of NDV-infected CEFs and suppressed the spread of NDV. These results indicate that baicalin has strong anti-NDV activity and has the potential for use as components of an antiviral drug.

Therapeutic effect of baicalin on experimental autoimmune encephalomyelitis is mediated by SOCS3 regulatory pathway

Natural compounds derived from medicinal plants have long been considered a rich source of novel therapeutic agents. Baicalin (Ba) is a bioactive flavonoid compound derived from the root of Scutellaria baicalensis, an herb widely used in traditional medicine for the treatment of various inflammatory diseases. In this study, we investigate the effects and mechanism of action of Ba in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Ba treatment effectively ameliorated clinical disease severity in myelin oligodendrocyte glycoprotein (MOG)35–55 peptide-induced EAE, and reduced inflammation and demyelination of the central nervous system (CNS). Ba reduced infiltration of immune cells into the CNS, inhibited expression of proinflammatory molecules and chemokines, and prevented Th1 and Th17 cell differentiation via STAT/NFκB signaling pathways. Further, we showed that SOCS3 induction is essential to the effects of Ba, given that the inhibitory effect of Ba on pathogenic Th17 responses was largely abolished when SOCS3 signaling was knocked down. Taken together, our findings demonstrate that Ba has significant potential as a novel anti-inflammatory agent for therapy of autoimmune diseases such as MS.

The effect of synthetic salidroside on cytokines and airway inflammation of asthma induced by diisocyanate (TDI) in mice by regulating GATA3/T-bet

This study was conducted to explore the anti-asthma effects of synthetic salidroside on cytokines and airway inflammation of asthma induced by diisocyanate (TDI) in mice. The experiment was carried out 60 female BALB/C mice which were randomly assigned to six experimental groups: control, vehicle, model, dexamethasone (2 mg/kg), and salidroside (24 and 48 mg/kg). After the experiment, histological studies were evaluated by the hematoxylin and eosin staining, the bronchoalveolar lavage fluid (BALF) and blood were collected from the animals, and the composition of the induced inflammatory cells, and the concentrations of certain cytokines (IL-4, INF-γ) were evaluated. GATA3 and T-bet mRNAs were evaluated by QPCR. Our study demonstrated that salidroside inhibited TDI-induced increases in eosinophil count; IL-4 and INF-γ were recovered. Histological studies demonstrated that salidroside substantially inhibited TDI-induced eosinophilia in lung tissue. Salidroside can improve T-bet mRNA and reduce GATA3 mRNA in lung. These findings suggest that salidroside may effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma by regulating GATA3/T-bet balance.

Early-Life Exposure to Clostridium leptum Causes Pulmonary Immunosuppression

INTRODUCTION

Low Clostridium leptum levels are a risk factor for the development of asthma. C. leptum deficiency exacerbates asthma; however, the impact of early-life C. leptum exposure on cesarean-delivered mice remains unclear. This study is to determine the effects of early-life C. leptum exposure on asthma development in infant mice.

METHODS

We exposed infant mice to C. leptum (fed-CL) and then induced asthma using the allergen ovalbumin (OVA).

RESULTS

Fed-CL increased regulatory T (Treg) cells in cesarean-delivered mice compared with vaginally delivered mice. Compared with OVA-exposed mice, mice exposed to C. leptum + OVA did not develop the typical asthma phenotype, which includes airway hyper-responsiveness, cell infiltration, and T helper cell subset (Th1, Th2, Th9, Th17) inflammation. Early-life C. leptum exposure induced an immunosuppressive environment in the lung concurrent with increased Treg cells, resulting in the inhibition of Th1, Th2, Th9, and Th17 cell responses.

CONCLUSION

These findings demonstrate a mechanism whereby C. leptum exposure modulates adaptive immunity and leads to failure to develop asthma upon OVA sensitization later in life.

Identification and Characterization of Baicalin as a Phosphodiesterase 4 Inhibitor

Asthma is a chronic inflammatory disease of lung airways, and pharmacological inhibitors of cyclic adenosine monophosphate-specific phosphodiesterase 4 (PDE4) have been considered as therapeutics for the treatment of asthma. However, development of PDE4 inhibitors in clinical trials has been hampered because of the severe side effects of non-selective PDE4 inhibitors. Here, screening of a plant extract library in conjunction with dereplication technology led to identification of baicalin as a new type of PDE4-selective inhibitor. We demonstrated that while rolipram inhibited the enzyme activity of a range of PDE4 subtypes in in vitro enzyme assays, baicalin selectively inhibited the enzyme activity of PDE4A and 4B. In addition, baicalin suppressed lipopolysaccharide-induced TNF-α expression in macrophage where PDE4B plays a key role in lipopolysaccharide-induced signaling. Furthermore, baicalin treatment in an animal model of allergic asthma reduced inflammatory cell infiltration and TNF-α levels in bronchoalveolar lavage fluids, indicating that the antiinflammatory effects of baicalin in vivo are attributable, in part, to its ability to inhibit PDE4.

Soshiho-tang water extract inhibits ovalbumin-induced airway inflammation via the regulation of heme oxygenase-1

Background

Soshiho-tang, known as Xio-hai-Hu-Tang in Chinese and Sho-Saiko-to in Japanese, has been widely used as a therapeutic agent. Its pharmacological effects include anti-inflammatory, antioxidant, antihepatic fibrosis, antitumor and immunomodulating activities. However, little is known regarding its effects on allergic asthma. Therefore, the aim of the present study was to investigate whether the Soshiho-tang water extract (SSTW) has antiasthmatic effects on airway inflammation in an ovalbumin (OVA)-induced mouse model.

Methods

BALB/c mice were used as a model of asthma after induction by sensitization and challenge with OVA. We measured change in eosinophils, other inflammatory cells, and T helper 2 (Th2)-type cytokines, such as interleukin (IL)-4, IL-5, IL-13, IL-17, IL-33, and chemokine (eotaxin) in bronchoalveolar lavage fluid (BALF), presence of total and OVA-specific immunoglobulin (Ig)E in plasma, and expression of mucus production and heme oxygenase (HO)-1 protein in lung tissue.

Results

Our results show that SSTW had a suppressive effect on eosinophil influx into BALF and decreased the levels of Th2-type cytokines. Moreover, SSTW exhibited a marked decrease in mucus hypersecretion, total and OVA-specific IgE levels, and significantly induced HO-1 protein expression.

Conclusions

These results suggest that SSTW may be used as a valuable therapeutic agent for treating various inflammatory diseases including allergic asthma.

Spectroscopic investigation on the food components-drug interaction: the influence of flavonoids on the affinity of nifedipine to human serum albumin

Nifedipine (NDP) is used extensively for the clinical treatment of a number of cardiovascular diseases. Herein, the interaction between human serum albumin (HSA) and NDP and the influence of flavonoids, rutin and baicalin, on their binding properties were investigated in vitro by means of fluorescence and absorption spectroscopy. The fluorescence of HSA was quenched remarkably by NDP and the quenching mechanism was considered as static quenching by forming a complex. The results of thermodynamic parameters indicate that both hydrogen bonds and hydrophobic interactions play the main role in the binding process and the binding process was spontaneous. The binding distance between the amino acid residue of HSA and NDP is 2.608 nm, which indicates that the energy transfer from HSA to NDP can occur with high probability. The decreased association constants and the increased binding distance of NDP binding to HSA in the presence of flavonoids were both due to their competitive binding to the site I of HSA. The results obtained from synchronous fluorescence and three-dimensional fluorescence spectra showed that the interaction between HSA and NDP caused the conformational changes of HSA and the synergism effects of NDP and flavonoids induced the further conformational changes of HSA.

Immunosuppressive effect of Chinese medicine on T helper 17 cells

T helper (Th)17 cells have been proposed to play important roles in several human diseases. The literatures about Chinese medicine studies, which related to inhibiting Th17, were reviewed, and the Chinese medicine which could inhibit Th17 cells was summarized in this paper.

Inhibitory effect of sihuangxiechai decoction on ovalbumin-induced airway inflammation in Guinea pigs

The aim of this study was to investigate the effect of sihuangxiechai decoction on asthmatic Guinea pig model which was sensitized by intraperitoneal (i.p.) injection of ovalbumin (OVA) and challenged by OVA inhalation to induce chronic airway inflammation. Differential cell counts of cytospins were performed after staining with Giemsa solution. The quantity of leukocytes and its classification in bronchoalveolar lavage fluid (BALF) and blood were evaluated by blood cell analyzer and microscope. Histological analysis of the lung was performed by hematoxylin and eosin (H&E) staining. The levels of interleukin-4 (IL-4) and tumor necrosis factor-alpha (TNF-α) in BALF and serum were detected by radioimmunoassay (RIA). The total number of leukocytes in BALF and blood has no significant difference between Sihuangxiechaitang decoction treated group and dexamethasone (DXM) treated group but was significantly lower than those of asthma group. The percentage of eosinophils in lung tissues of sihuangxiechai decoction treated group was significantly lower than that of asthma group. The results demonstrated that the levels of IL-4 and TNF-α in the sihuangxiechai decoction treated group were significantly reduced compared with the asthma group. In conclusion, these findings demonstrate that sihuangxiechai decoction has a protective effect on OVA-induced asthma in reducing airway inflammation and airway hyperresponsiveness (AHR) in a Guinea pig model and may be useful as an adjuvant therapy for the treatment of bronchial asthma.