Airway Inflammation In Asthmatic Rats Research Articles

Acupoint Autohemotherapy Alleviates Airway Inflammation in Asthmatic Rats via Upregulating Expression of Hemeoxygenase-1.

Acupoint autohemotherapy (AA), a therapeutic technique involving the subcutaneous injection of autologous blood into acupoints, has been empirically validated as safe and effective for treating asthma by alleviating symptoms and decreasing acute attacks, though its mechanism is not well understood. The role of heme oxygenase-1 (HO-1) in AA-induced suppression of asthmatic airway inflammation is examined. Twenty rats were assigned randomly to four groups, namely the Control, OVA, OVA + AA, and (OVA + Snpp) + AA. Rats in the OVA + AA and (OVA + Snpp) + AA received autologous blood injections into acupoints (BL13 and BL23) following OVA challenge. Rats in the (OVA + Snpp) + AA were concurrently subjected to intraperitoneal injections of Snpp, a inhibitor of HO-1. Airway inflammation was evaluated through HE staining, while the concentrations of cytokines in BALF were quantified using ELISA. The mRNA and protein levels of RORγt (Th17-specific transcription factor), Foxp3 (Treg-specific transcription factor), and HO-1 in lung tissue were assessed through qRT-PCR and WB. HE staining indicated that airway inflammation was alleviated in the OVA + AA. The OVA + AA displayed significantly lower counts of total cells and eosinophils in the BALF compared to both the OVA and (OVA + Snpp) + AA. The ELISA demonstrated a significant decrease in levels of pro-inflamatory cytokines (IL-4, IL-17A), and an increase in levels of anti-inflamatory cytokines (IFN-γ, IL-10), in the OVA + AA when compared to both OVA and (OVA + Snpp) + AA. The qRT-PCR and WB analyses revealed an upregulation of HO-1 and Foxp3 expression, and a downregulation of RORγt expression, in the OVA + AA when compared to OVA and (OVA + Snpp) + AA. The involvement of HO-1 in the underlying mechanism responsible for the anti-inflammatory effects of AA is evident.

Effect of "joint treatment of lung and intestine" with moxibustion on lung function and airway inflammation in asthmatic rats

To investigate the role of moxibustion of "Feishu" (BL13)，"Tianshu" (ST25) for asthma by simultaneously treating lung and intestine (i.e., treating both lung and intestine at the same time) in asthmatic rats. A total of 48 SD rats were randomly divided into normal, model, lung treatment and joint-treatment of lung and intestine (joint-treatment) groups, with 12 rats in each. The asthma model was established by subcutaneous (bilateral back and inguinal regions) and intraperitoneal injection of mixture solution of albumin and Aluminium Hydroxide gel (on day 1st, and 9th) and followed by inhalation of atomized 1% ovalbumin (on day 15th, 20 min each time, once daily for 1 week). Moxibustion was applied to bilateral BL13 for rats of the lung treatment group or bilateral BL13 and ST25 for rats of the joint-treatment group. One hour after the intervention, the rats in the later three groups were separately given nebulized 1% ovalbumin solution inhalation for 20 min. The treatments were conducted once daily for 14 consecutive days. After intervention, the lung functions including the forced expiratory flow 25% (FEF 25%), maximal mid-expiratory flow (MMEF), dynamic lung compliance (Cdyn), forced expiratory volume/ forced vital capacity (FEV/FVC), peak expiratory flow (PEF), and lung resistance (RL) were measured by using a small animal lung function detector, and pathological changes and collagen deposition in the lung tissues were observed by H.E. and Masson staining, separately. The levels of interleukin (IL)-17, IL-4, IL-13, IL-33, IL-5, leukotriene (LT) and thymic stromal lymphocyte (TSLP) in the lung tissue were measured by ELISA. Compared with the normal group, the FEF 25%, MMEF， Cdyn， FEV/FVC and PEF were significantly decreased (P<0.05, P<0.01)， and the pulmonary RL, collagen deposition, and contents of IL-17, IL-4, IL-13, IL-33, IL-5, TSLP and LT were notably increased (P<0.05, P<0.01) in the model group. After intervention, the MMEF and Cdyn in the lung treatment group, PEF, MMEF, Cdyn, FEV/FVC, FEF 25% in the joint-treatment group, were markedly increased (P<0.05, P<0.01), whereas the collagen deposition, IL-17, IL-4 and TSLP in both the lung treatment and joint-treatment groups, RL, IL-13, IL-33, IL-5 and LT in the joint-treatment group were considerably down-regulated (P<0.05, P<0.01). The effects of the joint treatment were apparently superior to those of lung treatment in down-regulating the contents of TSLP and LT (P<0.05, P<0.01). H.E. staining showed thickened alveolar wall, infiltration of a large number of inflammatory cells in the bronchus of the model group, which was relatively milder in the joint-treatment group. "Joint treatment of lung and intestine" with moxibustion is superior to "lung treatment" alone in ameliorating the lung function and mitigating airway inflammation in rats with asthma.

Effects of Houpo Mahuang Decoction on serum metabolism and TRPV1/Ca2+/TJs in asthma

Ethnopharmacological relevanceHoupo Mahuang Decoction (HPMHD is one of the classic traditional Chinese prescriptions that has been used in the treatment of asthma. The therapeutic effects and mechanism of HPMHD in aggravated asthma remain to be explored, especially from the perspective of metabolomics and Transient Receptor Potential Vanilloid-1 (TRPV1)/Ca2+/Tight junction (TJ) regulation. Aim of the studyTo investigate the therapeutic and metabolic regulatory effects and the underlying mechanism of HPMHD in asthmatic rats. Materials and methodsThe asthmatic rats were administered with the corresponding HPMHD (at dosages of 5.54, 11.07, 22.14 mg/kg). Then inflammatory cells in peripheral blood and bronchoalveolar lavage fluid (BALF) were counted, the levels of interleukin (IL)-4 and IL-13 in BALF were measured, and the changes in enhanced pause (Penh) and pathological damage of lung tissues were also detected to evaluate the protective effects of HPMHD. The serum metabolic profile of HPMHD in asthmatic rats was explored using Ultra-High-Performance Liquid Chromatography-mass spectrometer (UHPLC-MS), and the regulatory effects on TRPV1 and TJs of HPMHD in asthmatic rats were detected by Western blotting analysis. In vitro, 16HBE cells were stimulated with IL-4 plus SO2 derivatives and then administered HPMHD. The intracellular Ca2+ regulated by TRPV1, and the expression levels of TRPV1 and TJ proteins (TJs) were then detected by calcium imaging and Western blotting. The effects were verified by inhibition of TRPV1 and in short hairpin RNA (shRNA)-mediated TRPV1 silencing cells. ResultsHPMHD significantly attenuated the airway inflammation of asthmatic rats, and reduced the levels of inflammatory cells in peripheral blood and BALF as well as the levels of IL-4 plus IL-13 in BALF. In addition, the airway hyperresponsiveness and lung pathological damage were alleviated. Serum metabolomic analysis showed that 31 metabolites were differentially expressed among the normal saline-, model-, and HPMHD-treated rats. Pathway enrichment analysis showed that the metabolites were involved in 45 pathways, among which, TJs regulation-relevant pathway was associated with the Ca2+ concentration change mediated by the TRP Vanilloid channel. In vivo and in vitro experiments indicated that HPMHD reduced the concentration of intracellular Ca2+ via suppressing the expression and activation of TRPV1, increased the expression of ZO-1, Occludin, and Claudin-3, and protected the integrity of TJs. ConclusionThe current study indicates that HPMHD alleviates rat asthma and participates in the regulation of serum metabolism. The anti-asthma effects of HPMHD might be related to the protection of TJs by inhibiting the intracellular Ca2+ concentration via TRPV1.

Effect of acupuncture preconditioning combined with PI3K blocker LY294002 on airway inflammation in asthmatic rats

To observe the effect of acupuncture preconditioning combined with PI3K blocker LY294002 on the expression of PI3K and Akt proteins and genes in the lung tissue and the contents of serum IL-12 and IL-13 in asthmatic rats, so as to explore its preprotective mechanism underlying improving asthma. Sixty male Wistar rats were randomly divided into blank control, model, acupuncture pretreatment + blank, acupuncture pretreatment, acupuncture pretreatment + LY294002 and LY294002 groups (n=10 in each group). The asthma model was established by intraperitoneal injection of mixture solution of OVA and Al(OH)3 and followed inhalation of 1%OVA for 30 min, once daily for 7 days. Rats of the blocker groups received inhalation of atomized LY294002 solution for 30 min before inhalation of 1% OVA, and acupuncture was applied to "Feishu"(BL13), "Dazhui"(GV14) and "Fengmen"(BL12) for 20 min, once daily for 7 days before modeling. H.E. staining was used to assess histopathological changes of the lung tissue, and ELISA was used to detect the contents of serum IL-12 and IL-13. The immunoactivity of PI3K and Akt and expression of Akt mRNA of the lung tissue were detected by using immunohistochemistry and fluorescence quantitative real-time PCR, separately. Compared with the blank control group, the content of serum IL-12 was significantly decreased (P<0.01), and the content of serum IL-13, the expression levels of PI3K, Akt protein and Akt mRNA were remarkably increased (P<0.01) in the model group. In comparison with the model group, the content of serum IL-12 in the pretreatment, pretreatment + LY294002 and LY294002 groups was significantly increased (P<0.01, P<0.05), while the content of IL-13 and the expression levels of PI3K, Akt protein and Akt mRNA were considerably decreased (P<0.01, P<0.05) in the acupuncture pretreatment, acupuncture pretreatment+LY294002 and LY294002 groups. The therapeutic effect of acupuncture pretreatment+LY294002 was obviously superior to that of simple acupuncture pretreatment and LY294002 (except PI3K and Akt in the LY294002 group) in up-regulating serum IL-12 level, and in down-regulating serum IL-13, and PI3K and Akt protein levels in the lung tissue (P<0.01). H.E. staining showed severe inflammatory factor infiltration in the bronchus and pulmonary interstitium, and obvious bronchial lumen narrowing with increased exudate in rats of the model group, which was relatively milder in rats of the acupuncture pretreatment, acupuncture pretreatment+LY294002 and LY294002 groups. There were no significant diffe-rences between blank control and pretreatment+blank groups in all of the above indicators （P>0.05）. Acupuncture preconditioning can inhibit airway inflammation in asthmatic rats, which may be associated with its functions in down-regulating the levels of pulmonary PI3K and Akt and serum IL-13 and up-regulating the content of serum IL-12. Acupuncture preconditioning combined with LY294002 has the best effect.

Effect of Huai Qi Huang on asthma in rats and the mechanism research

To study the role and mechanism of action of Huai Qi Huang (HQH) in the rat model of asthma. Forty Sprague-Dawley rats were randomly divided into a control group, an asthma model group, a budesonide group, and an HQH group, with 10 rats in each group. A rat model of asthma was established by ovalbumin sensitization and challenge. The budesonide group was given budesonide aerosol 2 mg before each challenge. The HQH group was given HQH 4 g/kg dissolved in water by gavage before each challenge. Hematoxylin and eosin staining was used to observe the pathological changes of lung tissues. The percentage of eosinophils in bronchoalveolar lavage fluid (BALF) was measured. Enzyme-linked immunosorbent assay was used to determine the levels of interleukin-3 (IL-3), interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-10 (IL-10), interferon gamma (INF-γ), and immunoglobulin E (IgE) in BALF. Flow cytometry was used to determine T-helper type 1 (Th1)/T-helper type 2 (Th2) ratio in peripheral blood and the spleen. RT-PCR and Western blot were used to measure the mRNA and protein expression of T-bet and GATA-3 in lung tissue. Compared with the control group, the asthma model group showed significant increases in the degree of airway inflammation, the percentage of eosinophils in BALF, and the levels of IL-3, IL-4, IL-5 and IgE in BALF (P<0.05), however, the asthma model group showed significant reductions in the levels of IL-10 and INF-γ in BALF (P<0.05). The asthma model group had significantly lower percentage of Th1 cells but significantly higher percentage of Th2 cells in peripheral blood and the spleen compared with the control group (P<0.05). The mRNA and protein expression of T-bet in lung tissue was significantly lower, but the mRNA and protein expression of GATA-3 in lung tissue was significantly higher in the asthma group than those in the control group (P<0.05). Both HQH and budesonide significantly improved airway inflammation and the above markers in asthmatic rats (P<0.05), with comparable effects between them. However, there were still significant differences in these indices between the control group and the HQH or budesonide group (P<0.05). HQH can reduce the airway inflammation of asthmatic rats and alleviate the symptoms of asthma, possibly by regulating the levels of related cytokines and Th1/Th2 ratio through the T-bet/GATA-3 pathway.

Tobacco smoking aggravates airway inflammation by upregulating endothelin-2 and activating the c-Jun amino terminal kinase pathway in asthma

BackgroundAsthma is closely associated with tobacco smoking (TS) and is more difficult to effectively treat after exposure to TS. ObjectiveTo observe the effects of TS on the expression of endothelin-2 (ET-2) and airway inflammation in asthmatic rats and to explore the related mechanisms. MethodsWe established an animal model of asthma with ovalbumin (OVA)/Al(OH)3 and subjected different animal groups to TS and/or dexamethasone/bosentan. The differences in the inflammatory cell infiltration, the pathological changes to the bronchial wall and the bronchial smooth muscle thickness, and the expression of ET-2, c-Jun amino terminal kinase (JNK1/2), malondialdehyde (MDA), and glutathione peroxidase (GSH) in the lung tissue and of interleukin (IL)-7 in bronchoalveolar lavage fluid (BALF) were assessed. ResultsExposure to TS or OVA caused an obvious increase in the inflammatory cells in the BALF over what was observed in the control group. In asthma models, the expression of ET-1, JNK1/2, MDA, and GSH in the lung tissues, as well as that of IL-17 in the BALF, was increased. After treatment with dexamethasone/bosentan, the expression of IL-17, JNK1/2, MDA, and GSH decreased compared to the smoking group; airway inflammation and the staining intensity in the lung tissue were also reduced. ConclusionTS exposure can clearly exacerbate airway inflammation in asthmatic rats, while bosentan can alleviate airway inflammation through regulation of the ET-2/JNK1/2 signalling pathway.

Nobiletin Stimulates Chloride Secretion in Human Bronchial Epithelia via a cAMP/PKA-Dependent Pathway

Background/Aims: Nobiletin, a citrus flavonoid isolated from tangerines, alters ion transport functions in intestinal epithelia, and has antagonistic effects on eosinophilic airway inflammation of asthmatic rats. The present study examined the effects of nobiletin on basal short-circuit current (I_SC) in a human bronchial epithelial cell line (16HBE14o-), and characterized the signal transduction pathways that allowed nobiletin to regulate electrolyte transport. Methods: The I_SC measurement technique was used for transepithelial electrical measurements. Intracellular calcium ([Ca²⁺]_i) and cAMP were also quantified. Results: Nobiletin stimulated a concentration-dependent increase in I_SC, which was due to Cl^- secretion. The increase in I_SC was inhibited by a cystic fibrosis transmembrane conductance regulator inhibitor (CFTR_inh-172), but not by 4,4'-diisothiocyano-stilbene-2,2'-disulphonic acid (DIDS), Chromanol 293B, clotrimazole, or TRAM-34. Nobiletin-stimulated I_SC was also sensitive to a protein kinase A (PKA) inhibitor, H89, and an adenylate cyclase inhibitor, MDL-12330A. Nobiletin could not stimulate any increase in I_SC in a cystic fibrosis (CF) cell line, CFBE41o-, which lacked a functional CFTR. Nobiletin stimulated a real-time increase in cAMP, but not [Ca²⁺]_i. Conclusion: Nobiletin stimulated transepithelial Cl^- secretion across human bronchial epithelia. The mechanisms involved activation of adenylate cyclase- and cAMP/PKA-dependent pathways, leading to activation of apical CFTR Cl^- channels.

Regulatory effects of luteolin on airway inflammation in asthmatic rats

To explore the regulatory effects of luteolin on airway inflammation in asthmatic rats. A total of 48 male Sprague-Dawley (SD) rats were randomly divided into 3 groups of control, asthmatic and luteolin(n = 16 each). The rat model of bronchial asthma was established in asthmatic and luteolin groups. The model was induced by intraperitoneally injecting a mixture of ovalbumin and aluminum hydroxide at Day 1 and 8. After two weeks, aomization excitation of normal saline (containing 1% ovalbumin) was induced thrice weekly. The treatment lasted 8 weeks. In control group, the mixture of ovalbumin, aluminum hydroxide and normal saline containing 1% ovalbumin was replaced by normal saline. At 30 min after aomization excitation, normal saline was given to rats in control and asthmatic groups, while 1 mg/kg luteolin was given intraperitoneally to luteolin group. The inflammatory cell number and level of interleukin-4 (IL-4) were measured in bronchoalveolar lavage fluid (BALF). The histopathological changes were observed under light microscope. The activities of peroxisome proliferator-activated receptors (PPARγ) and p38 mitogen-activated protein kinases (p38MAPK) in pulmonary tissues were detected by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). The bronchial wall thickness of asthma group, along with smooth muscle thickness ((93.3 ± 7.4), (34.9 ± 2.3) µm) was more than that of control ((61.9 ± 8.2), (19.3 ± 1.5) µm) and luteolin ((76.6 ± 6.7), (25.4 ± 4.6) µm) groups (all P < 0.05). The total cell count ((5.61 ± 0.63)×10(9)/L), neutrophil count ((1.83 ± 0.09)×10(9)/L), eosinophil count ((0.59 ± 0.09)×10(9)/L) and level of IL-4 ((78.23 ± 12.73) pg/ml) in BALF of asthmatic group were markedly higher than those of control ((1.53 ± 0.31)×10(9)/L, (0.45 ± 0.21)×10(9)/L, (0.07 ± 0.03) ×10(9)/L and (21.21 ± 2.53) pg/ml) and luteolin ((3.24 ± 0.25)×10(9)/L, (1.54 ± 0.10)×10(9)/L, (0.33 ± 0.05)×10(9)/L and (43.24 ± 8.65) pg/ml) groups (all P < 0.05). The results of semi-quantitative immunohistochemical analysis showed that the p38 protein level in control group (0.143 ± 0.017) and luteolin group (0.251 ± 0.021) was significantly less than that in asthmatic group (0.362 ± 0.008) (both P < 0.01). As compared with asthmatic group, the expression of PPARγ protein markedly increased (0.247 ± 0.034) in control (0.331 ± 0.056) and luteolin (0.442 ± 0.031) groups (all P < 0.05). The level of p38 mRNA in asthmatic group (0.718 ± 0.064) was significantly higher than that of control (0.312 ± 0.052) and luteolin (0.426 ± 0.067) groups (all P < 0.01). However, the PPARγ mRNA level in asthmatic group (0.266 ± 0.036) was much less than that in control (0.573 ± 0.042) and luteolin (0.687 ± 0.054) groups (all P < 0.01). The anti-inflammatory effects of luteolin may be associated with the regulation of PPARγ expression and p38MAPK signaling pathway in asthmatic rats.

Effect of low-level laser therapy on allergic asthma in rats

Asthma is a complex chronic inflammatory disease of the airways that involves the activation of many inflammatory and other types of cells. We investigated the effect of low-level laser therapy (LLLT) on allergic asthma in rats and compared its effect with that of the glucocorticoid budesonide. Asthma was induced by challenge and repeated exposure to ovalbumin. Asthmatic rats were then treated with LLLT or budesonide suspension. LLLT at 8 J/cm(2) once daily for 21 days could relieve pathological damage and airway inflammation in asthmatic rats. LLLT could decrease the total numbers of cells and eosinophils in bronchoalveolar lavage fluid. LLLT could reduce levels of IL-4 and increase IFN-γ levels in bronchoalveolar lavage fluid and serum, meanwhile reduce serum IgE levels. Flow cytometry assay showed that LLLT can regulate the Th1/Th2 imbalance of asthmatic rats. LLLT had a similar effect to that of budesonide. These findings suggest that the mechanism of LLLT treatment of asthma is by adjustment of Th1/Th2 imbalance. Thus, LLLT could take over some of the effects of budesonide for the treatment of asthma, thereby reducing some of the side effects of budesonide.

Interleukin (IL)-4 induces production of cytokine-induced neutrophil chemoattractants (CINCs) and intercellular adhesion molecule (ICAM)-1 in lungs of asthmatic rats

The present study aimed to examine the effect of interleukin (IL)-4 on neutrophil chemotaxis in airway inflammation in asthmatic rats and the possible mechanism. Male Wistar rats were intranasally instilled with recombinant rat (rr) IL-4 (rrIL-4) at different doses [2, 4 or 8 μg/animal, dissolved in 200 μL normal saline (NS)] or rrIL-4 at 4 μg/animal (dissolved in 200 μL NS). NS (200 μL) and LPS (6 mg/kg/animal, dissolved in 200 μL NS) were intranasally given respectively in the negative and positive control groups. Moreover, the asthmatic lung inflammation was induced in rats which were then intranasally treated with rrIL-4 (4 μg/animal) or LPS (6 mg/kg/animal). The normal rats treated with different doses of rrIL-4 and those asthmatic rats were sacrificed 6 h later. And animals instilled with rrIL-4 at 4 μg were sacrificed 6, 12 or 24 h later. The bronchoalveolar lavage fluid (BALF) and lungs were harvested for detection of leukocyte counts by Wright-Giemsa staining and lung histopathology by haematoxylin-eosin (HE) staining. The levels of cytokine-induced neutrophil chemoattractant (CINC)-1 and intercellular adhesion molecule (ICAM)-1 in BALF were determined by ELISA. Real-time PCR was used to measure the mRNA expression of CINCs (CINC-1, CINC-2α, CINC-2β, CINC-3) and ICAM-1 in lung tissues. The results showed that the intranasal instillation of IL-4 did not induce a recruitment of neutrophils in BALF in rats. However, IL-4 could increase the CINC-1 level in BALF in a dose-dependent manner at 6 h. But the mRNA expression levels of CINC-1, CINC-2α, CINC-2β, CINC-3 were not significantly increased in lungs of IL-4-treated rats relative to NS negative control group. Moreover, IL-4 was found to augment the mRNA expression of ICAM-1 in lungs and the ICAM-1 level in BALF at 6 h. However, the increase in CINC-1 and ICAM-1 levels in BALF of IL-4-treated asthmatic rats was not significantly different from that in untreated asthmatic rats. These findings indicate that IL-4 does not directly recruit neutrophils in the rat lungs, but it may contribute to airway neutrophilia through up-regulation of CINC-1 and ICAM-1.

Zinc Suppressed the Airway Inflammation in Asthmatic Rats: Effects of Zinc on Generation of Eotaxin, MCP-1, IL-8, IL-4, and IFN-γ

Airway epithelium is rich in labile zinc (Zn), which may have an important protective role in the airway epithelium. The aim of this study is to investigate the effects of Zn on the airway inflammation and the generation of eotaxin, monocyte chemoattractant protein-1 (MCP-1), interleukin-8 (IL-8), interleukin-4 (IL-4), and interferon-γ (IFN-γ) in rat models of ovalbumin (OVA)-induced allergic airway inflammation. For this purpose, animal model of asthma was established by OVA challenge and zinc-deficient and zinc-supplemented diets were given. Thirty-two Sprague-Dawley rats were divided into four groups: zinc-deficient diet with OVA treatment group, zinc-supplemented diet with OVA treatment group, zinc-normal diet with OVA treatment group, and zinc-normal diet with saline treatment group. Twenty-four hours after asthma was induced, lung histomorphological changes, cells in bronchoalveolar lavage fluid (BALF), contents of eotaxin, MCP-1, and IL-8 in BALF, and the expression of IFN-γ and IL-4 mRNAs were observed. Compared with the group of zinc-normal diet with OVA challenge rats, the group of zinc-deficient rats had higher numbers of eosinophils, neutrophils, and monocytes in BALF, as well as higher contents of eotaxin and MCP-1 in BALF and lower expression of lung IFN-γ mRNA. Conversely, Zn supplementation would decrease the numbers of eosinophils, neutrophils, and monocytes in BALF; suppress eotaxin and MCP-1 protein secretion; and increase lung IFN-γ mRNA expression. No significant difference was observed in IL-8 and IL-4 among OVA-challenged rats with different zinc diets. These studies suggested that Zn may be an important anti-inflammatory mediator of airway inflammation.

Study on Th1/Th2 transcriptional regulatory mechanism of San'ao Tang in bronchial asthmatic rats

To study the regulatory effect of San'ao Tang on Thl/Th2 cells and its interference on transcription factor GATA-3 and T-bet-mRNA in asthmatic rats. Rat asthma model was established by abdominal injection and aerosol inhalation of OVA. The content of cytokines IL-4 and IFN-gamma in alveolus lavage fluid of asthmatic rats was detected before and after the oral administration with large, medium, low dose of San'ao Tang and dexamethasone. T-bet and GATA-3 mRNA expressions in lung tissues were determined by RT-PCR. Compared with other groups, the medium-dose group showed a notable decrease in IL-4 in rat BALF and an increasing IFN-gamma. Its IL-4/IFN-gamma is significant lower than the asthma group, with expressions of lung tissue GATA-3 and transcription factor T-bet-mRNA in line with changes in IL-4 and IFN-gamma. San'ao Tang may have a inhibitory effect on airway inflammation of asthmatic rats by regulating Th1/Th2 transfer factors.

Danshen injection decrease interleukin-13 and eotaxin expression in the lung of asthmatic rats

Objective To investigate the molecular mechanism of inhibitory effect of Danshen injection on allergic airway inflamma-tion of asthma. Methods 30 SD rats were random divided into control group, asthma group and Danshen injection group. Bronchoalveolar lavage fluid (BALF) was collected, and cytology study was conducted. The lung tissue was obtained and pathologic analysis was done through HE staining, lnterleukin-13 (IL-13) and Eotaxin in lung tissue were measured by RT - PCR and immunohistochemistry SP method. Results Compared with the asthma group, less infiltration of inflammatory cells in lung tissues was observed in the Danshen injection group. Total cell number, the percentage of lymphocytes, neutrophils and eosinophils (Eos) in BALF of Danshen injection group were lower than that of asthma group (P<0.05, P<0.01). The expression of IL-13 and eotaxin in lung tissue of asthma group was higher than that of control group and Danshen injection group (P<0.05). The expression of IL-13 was negatively correlated with eotaxin (r=0.90, P< 0.05). Conclusion Danshen injection could suppress airway inflammation of asthmatic rats, which probably be through decreasing the ex-pression of IL-13 and eotaxin in the lung tissue of asthmatic rats. Key words: DANSHEN INJECTION/PD; Asthma; Interleukin-13; Chemotactic factors,eosinophil

Influence of danshen injection combined with dexamethasone on CD4+CD25+ regulatory T cells of asthmatic rats

Objective To investigate the immunological mechanism of inhibitory effect of Danshen injection combined with dexamethasone(DXM) on asthmatic airway inflammation.Methods 50 Wistar rats were randomly divided into normal control(NC),asthma,Danshen,DXM and Danshen+DXM group.Cytology study of Bronchoalveolar lavage fluid(BALF) was conducted.Pathology of lung tissue was done through HE.Flow eytometry was used to detect CD4+CD25+ regulatory T Cells(CD4+CD25+ Treg) ratio in peripheral blood mononuclear cells(PBMCs).IL-4 and IL-5 levels in BALF were detected by ELISA.Results Total cells number,percentage of lymphocytes,neutrophils and eosinophils(Eos) in BALF of the three treated groups were lower than that in asthma group(P<0.05,P<0.01),particularly in Danshen+DXM group,which showed significant difference as compared with the other two treated groups(P<0.05).There was severe inflammation in lung tissue of asthma group,moderate inflammation in Danshen group and DXM group,and no inflammation of Danshen+DXM group.CD4+CD25+ Treg/CD4+ T ratio in the three treated groups were higher than that in asthma group,and the levels of IL-4 and IL-5 were lower than those in asthma group(P<0.05).In Dansben+DXM group,it showed significant difference on the change of CD4+CD25+ Treg,IL-4 and IL-5 as compared with other treated groups(P<0.05).Conclision Danshen injection combined with DXM could suppress airway inflammation in asthmatic rats,which may be through increasing the expression of CD4+CD25+ Treg,decreasing the levels of IL-4 and IL-5 and resuming the balance of Th1/Th2. Key words: DANSHEN INJECTION/PD; Dexamethasone/PD; Antigens,CD4; Receptors,interleukin-2; T-lymphocytes

Antagonistic effects of nobiletin, a polymethoxyflavonoid, on eosinophilic airway inflammation of asthmatic rats and relevant mechanisms

Eosinophils are known to be the important effector cells in asthmatic airway inflammation. The purpose of this study was to investigate the effects of nobiletin, a polymethoxyflavonoid, on eosinophilic airway inflammation of asthmatic rats, and explore its possible mechanisms. Animals were actively sensitized by subcutaneous injection of ovalbumin (OVA). The inflammation in lung tissues of asthmatic rats was observed by hematoxylin and eosin (HE) staining. The eosinophils in blood and BALF were separated by Percoll density gradient centrifugation and counted under microscope. The level of Eotaxin was detected by enzyme-linked immunosorbent assay (ELISA). In addition, the apoptosis of eosinophils was labeled by TdT-mediated dUTP nick end labeling (TUNEL) technique, the semi-quantitative detection for Fas mRNA expression of eosinophils was performed by reverse transcription-polymerase chain reaction (RT-PCR). The airway inflammation of asthmatic rats pretreated with nobiletin was obviously alleviated. Nobiletin (1.5 and 5.0 mg/kg given intraperitoneally) significantly reduced OVA-induced increases in eosinophils, remarkably lowered the level of Eotaxin in blood and broncho-alveolar lavage fluid (BALF) of asthmatic rats. On the other hand, semi-quantitative RT-PCR analysis for Fas of eosinophils from OVA aerosol-challenged sensitized rats showed that Fas mRNA expression of eosinophils was obviously enhanced by nobiletin. Meanwhile, the apoptosis index of cultured eosinophils was significantly elevated after treatment with different doses of nobiletin. These results indicated that nobiletin could inhibit the eosinophilic airway inflammation. Lowering the levels of Eotaxin, relieving airway infiltration of eosinophils and promoting apoptosis of eosinophils by enhancing expression of Fas mRNA may be important mechanisms for nobiletin to antagonize eosinophilic airway inflammation of asthmatic rats.

Effect of all-trans retinoic acid on airway inflammation in asthmatic rats and its mechanism.

The inhibitive effects of all-trans retinoic acid (ARTA) on airway inflammation in asthmatic rats and its mechanism on the basis of the regulation of nuclear factor kappaB (NF-kappaB) were explored. Thirty-two SD rats were randomly divided into 4 groups: control group, asthma group, dexamethasone treatment group and retinotic acid treatment group. The total and differential cell counts in the collected bronchoalveolar lavage fluid (BALF) were measured. The pathological changes in lung tissues were estimated by scoring. The expression of NF-kappaB inhibitor (IkappaBa), NF-kappaB, intercellular adhering molecule-1 (ICAM-1) in lung tissue was detected by immunohistochemical method. The results showed that in the two treatment groups, the total cell counts and proportion of inflammatory cells in BALF were significantly reduced, but there was no significant difference in differential cell counts in BALF between them. The pathological changes in lung tissues in the treatment groups were significantly attenuated as compared with asthma group. Except the epithelial injury in retinotic acid treatment group was milder than in dexamethasone treatment group, the remaining lesions showed no significant difference between them. In the two treatment groups, the expression of IkappaBa was increased, while the expression of NF-kappaB and ICAM-1 decreased with the difference between the two groups being not significant. It was concluded that the similar anti-inflammatory effects and mechanism of ATRA on airway in asthmatic rats to those of dexamethasone were contributed to the increase of cytoplasmic IkappaBa content and suppression of NF-kappaB activation and expression.