Anti-asthmatic effect of schizandrin on OVA-induced airway inflammation in a murine asthma model

Preclinical Retinal Disease Models: Applications in Drug Development and Translational Research

Retinal models play a pivotal role in translational drug development, bridging preclinical research and therapeutic applications for both ocular and systemic diseases. This review highlights the retina as an ideal organ for studying advanced therapies, thanks to its immune privilege, vascular and neuronal networks, accessibility, and advanced imaging capabilities. Preclinical retinal disease models offer unparalleled insights into inflammation, angiogenesis, fibrosis, and hypoxia, utilizing clinically translatable bioimaging tools like fundoscopy, optical coherence tomography, confocal scanning laser ophthalmoscopy, fluorescein angiography, optokinetic tracking, and electroretinography. These models have driven innovations in anti-inflammatory, anti-angiogenic, and neuroprotective strategies, with broader implications for systemic diseases such as rheumatoid arthritis, Alzheimer's, and fibrosis-related conditions. By emphasizing the integration of the 3Rs principles and novel imaging modalities, this review highlights how retinal research not only enhances therapeutic precision but also minimizes ethical concerns, paving the way for more predictive and human-relevant approaches in drug development.

Guben Kechuan granule attenuates bronchial asthma by inhibiting NF-κB/STAT3 signaling pathway-mediated apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic asthma caused by allergies is a lung illness marked by airway remodeling and hyperresponsiveness. Guben Kechuan (GK) granule is a clinically proven formula for treating lung disease. It relieves cough and helps to clear phlegm, but the mechanisms underlying its treatment for asthma are not clear.

AIM OF THE STUDY

We aimed to elucidate the efficacy and potential mechanisms by which GK ameliorates allergic asthma.

MATERIALS AND METHODS

Ultra-performance liquid chromatography (UHPLC-LTQ-Orbitrap-MS) identified the main chemical components of GK. The efficacy of GK was studied in an ovalbumin/alum (OVA)/AL(OH)3-sensitized rat model of bronchial asthma by measuring cytokine concentrations in serum and alveolar lavage samples, examining tissue pathology, and performing leukocyte counts. The mechanisms underlying its effectiveness in asthma were investigated by both transcriptomic and proteomic analyses.

RESULTS

GK relieved asthma-induced airway inflammation and remodeling, reduced inflammatory cell infiltration, and decreased the levels of the inflammatory cytokines TNF-α, IL-4, IL-5, IL-6, and IL-10. Analysis of the transcriptomic and proteomic results found that asthma activated the transcription factors STAT3 and NF-κB and induced oxidative-stress damage and apoptosis. GK was found to reduce Bax and caspase-3 expression, increase Bcl-2 expression, and inhibit asthma-induced apoptosis. GK downregulated the expression of the transcription factors STAT3 and NF-kB, which decreased the inflammatory response. Decreases in CAT, SOD, and GSH reduced asthma-induced oxidative-stress damage.

CONCLUSIONS

Our findings provide evidence that GK alleviates bronchial asthma by inhibiting apoptosis and oxidative stress damage mediated by the NF-κB/STAT3 signaling pathway.

Preclinical Development of SHR-1819, a Potent Humanized IL-4Rα Antibody for Treating Type 2 Inflammatory Diseases

Background

Interleukin (IL)-4 and IL-13 are critical pathogenic factors for type 2 inflammation-related allergic diseases, sharing the mutual receptor subunit IL-4Rα. However, it was ineffective for certain type 2 inflammation diseases by targeting IL-4, IL-13 ligand alone or both in clinical studies. The work presented herein aimed to evaluate the preclinical efficacy and pharmacokinetics profile of a novel monoclonal antibody against IL-4Rα, SHR-1819, as a promising therapy for type 2 inflammation diseases.

Methods

SHR-1819 was generated through immunization by C57BL/6 mice with recombinant hIL-4Rα protein, followed by humanization and affinity maturation. Then, its binding properties with IL-4Rα were determined using surface plasmon resonance (SPR) and ELISA. In vitro inhibitory effects of SHR-1819 were assessed on hIL-4-/hIL-13-induced cell proliferation and signal transducer and activator of transcription 6 (STAT6) signaling activation. In vivo efficacy of SHR-1819 was evaluated in several type 2 inflammatory diseases models, including asthma, atopic dermatitis (AD), and allergic rhinitis (AR) by using hIL-4/hIL-4Rα transgenic mice. Furthermore, the pharmacokinetic (PK) profiles of SHR-1819 were characterized.

Results

SHR-1819 showed high binding affinity to human IL-4Rα and effectively blocked IL-4Rα at sub-nanomolar concentration. In vitro assays indicated that SHR-1819 significantly inhibited TF-1 cell proliferation and STAT6 activation induced by hIL-4/hIL-13. In the asthma model, SHR-1819 could reduce airway hyperresponsiveness, decrease serum IgE levels, and alleviated inflammatory lung cell infiltration. In the AD model, SHR-1819 could significantly alleviate inflammatory and skin symptoms. In the AR model, it could remarkably decrease the frequencies of nasal rubbing and sneezing, and inflammatory cell infiltration in nasal tissues. These in vivo efficacy studies demonstrated the therapeutic potential of SHR-1819 in preclinical disease models. Moreover, subcutaneous administration of SHR-1819 exhibited favorable bioavailability in mice.

Conclusion

The results supported SHR-1819 as a promising preclinical candidate for the treatment of type 2 inflammatory diseases, including asthma, AD and AR.

Schisandrol A, the Major Active Constitute in Schisandra chinensis: A Review of Its Preparation, Biological Activities, and Pharmacokinetics Analysis

Schisandra chinensis (S. chinensis) has a long history as a traditional Chinese medicine that is astringent, beneficial to vital energy, tonifies the kidney, tranquilizes the heart, etc. Significantly, Schisandrol A (SA) is extracted from S. chinensis and shows surprising and satisfactory biological activity, including anti-inflammatory, hepatoprotective, cardiovascular protection, and antitumor properties, among others. SA has a more pronounced protective effect on central damaged nerves among its numerous pharmacological effects, improving neurodegenerative diseases such as Alzheimer's and Parkinson's through the protection of damaged nerve cells and the enhancement of anti-oxidant capacity. Pharmacokinetic studies have shown that SA has a pharmacokinetic profile with a rapid absorption, wide distribution, maximal concentration in the liver, and primarily renal excretion. However, hepatic and intestinal first-pass metabolism can affect SA's bioavailability. In addition, the content of SA, as an index component of S. chinensis Pharmacopoeia, should not be less than 0.40%, and the content of SA in S. chinensis compound formula was determined with the help of high-performance liquid chromatography (HPLC), which is a stable and reliable method, and it can lay a foundation for the subsequent quality control. Therefore, this paper systematically reviews the preparation, pharmacological effects, pharmacokinetic properties, and content determination of SA with the goal of updating and deepening the understanding of SA, as well as providing a theoretical basis for the study of SA at a later stage.

Lonicerin alleviates ovalbumin-induced asthma of mice via inhibiting enhancer of zeste homolog 2/nuclear factor-kappa B signaling pathway

Asthma is the most common chronic disease in the respiratory system of children caused by abnormal immunity that responses to common antigens. Lonicerin exerts anti-inflammatory activity in other inflammatory models through targeting enhancer of zeste homolog 2 (EZH2) that is related to asthma. We sought to explore the role and mechanism of lonicerin in regulating allergic airway inflammation. Mice were intraperitoneally injected 10 µg ovalbumin (OVA) on postnatal day 5 (P5) and P10, and then inhaled 3% aerosolized OVA for 10 min every day on P18-20, to establish asthmatic mice model. Lonicerin (10 or 30 mg/kg) was given to mice by intragastric administration on P16-P20. Notably, the administration of lonicerin amended infiltration of inflammatory cells and mucus hypersecretion. OVA-specific IgE level, inflammatory cell count and inflammatory cytokines in asthmatic mice were reduced after lonicerin treatment. Moreover, it suppressed the activity of EZH2 and activation of nuclear factor-kappa B (NF-κB) as evidenced by decreasing tri-methylation of histone H3 at lysine 27 and reducing nuclear translocation of NF-κB p65. In a word, Lonicerin may attenuate asthma by inhibiting EZH2/NF-κB signaling pathway.

A comprehensive review on Schisandrin and its pharmacological features

Schisandrin stands as one of the primary active compounds within the widely used traditional medicinal plant Schisandra chinensis (Turcz.) Baill. This compound exhibits sedative, hypnotic, anti-aging, antioxidant, and immunomodulatory properties, showcasing its effectiveness across various liver diseases while maintaining a favorable safety profile. However, the bioavailability of schisandrin is largely affected by hepatic and intestinal first-pass metabolism, which limits the clinical efficacy of schisandrin. In this paper, we review the various pharmacological effects and related mechanisms of schisandrin, in order to provide reference for subsequent drug research and promote its medicinal value.

Camellia sinensis (L.) Kuntze Extract Attenuates Ovalbumin-Induced Allergic Asthma by Regulating Airway Inflammation and Mucus Hypersecretion

Asthma is a pulmonary disease induced by the inhalation of aeroallergens and subsequent inappropriate immune responses. Camellia sinensis (L.) Kuntze has been evaluated as an effective antioxidant supplement produced from bioactive compounds, including flavonoids. In this study, we aimed to determine the effects of Camellia sinensis (L.) Kuntze extract (CE) on ovalbumin-induced allergic asthma. The components of CE were analyzed using high-performance liquid chromatography (HPLC) chromatogram patterns, and asthmatic animal models were induced via ovalbumin treatment. The antioxidant and anti-inflammatory effects of CE were evaluated using 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and nitric oxide (NO) assays. Seven compounds were detected in the CE chromatogram. In the ovalbumin-induced mouse model, CE treatment significantly decreased the inflammation index in the lung tissue. CE also significantly decreased eosinophilia and the production of inflammatory cytokines and OVA-specific IgE in animals with asthma. Collectively, our results indicate that CE has anti-inflammatory and antioxidant activities, and that CE treatment suppresses asthmatic progression, including mucin accumulation, inflammation, and OVA-specific IgE production.

Schisandrin A ameliorates airway inflammation in model of asthma by attenuating Th2 response

Asthma is a persistent respiratory ailment that displays periodicity and is linked to the equilibrium of T cells. Several compounds obtained from Chinese herbal medicines display beneficial impacts on T cell regulation and the attenuation of inflammatory mediator synthesis. Schisandrin A, an active lignan derived from the Schisandra fruit, exhibits anti-inflammatory characteristics. In the present study, the network analysis conducted revealed that the nuclear factor-kappaB (NF-κB) signaling pathway is likely a prominent contributor to the anti-asthmatic effects of schisandrin A. In addition, it has been established that the inhibition of cyclooxygenase 2 (COX-2/PTGS2) is likely a significant factor in this process. The results of in vitro experiments have substantiated that schisandrin A can effectively lower the expression of COX-2 and inducible nitric oxide synthase (iNOS) in 16 HBE cells and RAW264.7 cells in a manner that is dependent on the dosage administered. It was able to effectively reduce the activation of the NF-κB signaling pathway while simultaneously improving the injury to the epithelial barrier function. Furthermore, an investigation utilizing immune infiltration as a metric revealed an inequity in Th1/Th2 cells and a surge in Th2 cytokines in asthma patients. In the OVA-induced asthma mice model, it was observed that schisandrin A treatment effectively suppressed inflammatory cell infiltration, reduced the Th2 cell ratio, inhibited mucus secretion, and prevented airway remodeling. To summarize, the administration of schisandrin A has been found to effectively alleviate the symptoms of asthma by impeding the production of inflammation, which includes reducing the Th2 cell ratio and improving the integrity of the epithelial barrier function. These findings offer valuable insights into the potential therapeutic applications of schisandrin A for the treatment of asthma.

Experimental animal models of chronic inflammation

Inflammation is a general term for a wide variety of both physiological and pathophysiological processes in the body which primarily prevents the body from diseases and helps to remove dead tissues. It has a crucial part in the body immune system. Tissue damage can recruit inflammatory cells and cytokines and induce inflammation. Inflammation can be classified as acute, sub-acute, and chronic. If it remained unresolved and lasted for prolonged periods, it would be considered as chronic inflammation (CI), which consequently exacerbates tissue damage in different organs. CI is the main pathophysiological cause of many disorders such as obesity, diabetes, arthritis, myocardial infarction, and cancer. Thus, it is critical to investigate different mechanisms involved in CI to understand its processes and to find proper anti-inflammatory therapeutic approaches for it. Animal models are one of the most useful tools for study about different diseases and mechanisms in the body, and are important in pharmacological studies to find proper treatments. In this study, we discussed the various experimental animal models that have been used to recreate CI which can help us to enhance the understanding of CI mechanisms in human and contribute to the development of potent new therapies.

Fingolimod attenuates ovalbumin-induced airway inflammation via inhibiting MAPK/ERK signaling in mice

The current study was designed to investigate the potential anti-inflammatory and antioxidant effects of fingolimod against Ovalbumin (Ova)-induced allergic airway inflammation compared to dexamethasone. Fingolimod was given (0.5 mg/kg/day, p.o.) for sensitized mice 1 h before Ova challenge from Days 19 to 24. Fingolimod significantly inhibited Ova-induced elevation of inflammatory cells and eosinophils numbers in bronchoalveolar lavage fluid (BALF) and reduced concentrations of immunoglobulin E in serum and of sphingosine-1-phosphate, interleukin (IL)-4, and IL-13 in BALF. Fingolimod inhibited microvascular leakage and edema as reflected by the decreased lung/body weight index. These findings were supported by histopathological examination results showing that fingolimod substantially decreased perivascular edema and inflammatory cell infiltration. Fingolimod also attenuated Ova-induced oxidative stress as evidenced by decreased malondialdehyde concentration along with increasing concentrations of reduced glutathione and superoxide dismutase in lung tissues. Fingolimod also significantly decreased monocyte chemoattractant protein-1 (MCP-1), p-ERK, and p-P38 in lung tissues of Ova-challenged mice. In conclusion, the current study demonstrated the anti-inflammatory and antioxidant effects of fingolimod in allergic airway inflammation that might be associated with the downregulation of mitogen activated kinases signaling to decrease T helper 2 cytokine secretion (IL-4 and IL-13) and MCP-1 expression, along with the inhibition of oxidative stress.

Chemical Characterization and Potential Mechanism of the Anti-Asthmatic Activity of a Subfraction from Schisandra chinensis Fruit Extract

Schisandra chinensis fruit is a widely edible and medicinal resource, whose extract had a good inhibitory effect on airway inflammation in asthmatic mice. However, the main active components remain unknown. In this work, we found that PET2, a subfraction of its ethanolic extract petroleum ether, displayed significant anti-inflammatory effects in interleukin (IL)-4/tumor necrosis factor (TNF)-α-stimulated BEAS-2B cells. Meanwhile, in the ovalbumin (OVA)-induced allergic asthma mice model, PET2 (200 and 400 mg/kg) had significant effects on attenuating airway inflammatory cell infiltration and reducing serum Th2-related cytokines. Further studies led to the isolation and identification of 14 compounds, guided by ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS)-based rapid characterization of chemical constituents. Combining network pharmacology analysis and in vitro experiments, we found that six compounds from PET2 had good anti-inflammatory properties. The potential mechanism may be involved in Fc epsilon RI, T cell receptor, and Jak-STAT signaling pathways. This study clarified the anti-inflammatory properties of the main active fraction and active compounds of S. chinensis fruit and provided a theoretical basis for its anti-asthma scientific utilization.

Schisandrin B Attenuates Airway Inflammation and Airway Remodeling in Asthma by Inhibiting NLRP3 Inflammasome Activation and Reducing Pyroptosis

Asthma is a chronic inflammatory disorder of the airways. Schisandrin B (SB) is the main effective component. This study investigated the effects of SB on airway inflammation and airway remodeling in asthma. The rat model of asthma was established. The rats were treated with SB to evaluate the effects of SB on airway inflammation, airway remodeling, NLRP3 inflammasome activation, and pyroptosis. Alveolar macrophages of rats were isolated, and the macrophage inflammatory model was established by lipopolysaccharide (LPS) induction. The LPS-induced macrophages were treated with SB. The binding relationship between miR-135a-5p and TPRC1 was analyzed. LPS + SB-treated macrophages were transfected with miR-135a-5p inhibitor. The expressions of key factors of the STAT3/NF-κB pathway were detected. SB reduced airway inflammation and airway remodeling in asthmatic rats. SB inhibited NLRP3 inflammasome activation and reduced pyroptosis in asthmatic rats and LPS-induced macrophages. SB reversely regulated the miR-135a-5p/TRPC1 axis. Downregulation of miR-135a-5p attenuated the inhibitory effect of SB on NLRP3 inflammasome activation. SB inhibited the STAT3/NF-κB pathway via the miR-135a-5p/TRPC1 axis. In conclusion, SB inhibited NLRP3 inflammasome activation and reduced pyroptosis via the miR-135a-5p/TRPC1/STAT3/NF-κB axis, thus alleviating airway inflammation and airway remodeling in asthma. This study may confer novel insights for the management of asthma.

Schisandrin Protects against Norepinephrine-Induced Myocardial Hypertrophic Injury by Inhibiting the JAK2/STAT3 Signaling Pathway

Aims. Heart failure is closely associated with norepinephrine-(NE-) induced cardiomyocyte hypertrophy. Schisandrin is derived from the traditional Chinese medicine Schisandra; it has a variety of pharmacological activities, and the mechanism of schisandrin-mediated protection of the cardiovascular system is not clear. Main Methods. NE was used to establish a cardiomyocyte hypertrophy model to explore the mechanism of action of schisandrin. An MTT assay was used for cell viability; Hoechst fluorescence staining was used to observe the cell morphology and calculate the apoptosis rate. The cell surface area was measured and the protein to DNA ratio was calculated, changes in mitochondrial membrane potential were detected, and the degree of hypertrophic cell damage was evaluated. WB, QRT-PCR, and immunofluorescence were used to qualitatively, quantitatively, and quantitatively detect apoptotic proteins in the JAK2/STAT3 signaling pathway. Key Findings. In the NE-induced model, schisandrin treatment reduced the apoptosis rate of cardiomyocytes, increased the ratio of the cell surface area to cardiomyocyte protein/DNA, and also, increased the membrane potential of the mitochondria. The expression of both JAK2 and STAT3 was downregulated, and the BAX/Bcl-2 ratio was significantly reduced. In conclusion, schisandrin may protect against NE-induced cardiomyocyte hypertrophy by inhibiting the JAK2/STAT3 signaling pathway and reducing cardiomyocyte apoptosis.

Schisandrin B inhibits epithelial‑mesenchymal transition and stemness of large‑cell lung cancer cells and tumorigenesis in xenografts via inhibiting the NF‑κB and p38 MAPK signaling pathways

Lung cancer is one of the most common types of cancer in the world, resulting in numerous cancer‑associated deaths. The properties of cancer stem cells (CSCs) are important for the initiation and deterioration of lung cancer. Schisandrin B (SchB), an active compound extracted from Schisandra chinensis, exerts anticancer effects in various malignancies, including lung cancer. Nevertheless, the potential of SchB in epithelial‑mesenchymal transition (EMT) and CSC features of large‑cell lung cancer remains unclear. The present study established cancer stem‑like cells derived from large‑cell lung cancer cells, NCI‑H460 and H661, and revealed that SchB inhibited the viability of cancer stem‑like cells at concentrations of ≥40 µmol/l. Moreover, SchB prominently inhibited cell migration, invasion and EMT. Sphere‑forming assays and western blotting demonstrated that the stemness of cancer stem‑like cells was alleviated by SchB treatment. Mechanistically, the current findings revealed that SchB contributed to the suppression of the NF‑κB and p38 MAPK signaling pathways. Notably, further results revealed that the malignant behaviors of NCI‑H460‑CSCs induced by the activation of the NF‑κB and p38 MAPK signaling pathways were suppressed by SchB treatment. Consistently, the inhibitory role of SchB in EMT and CSC activities, as well as in the activation of the NF‑κB and p38 MAPK signaling pathways, was confirmed in vivo. In conclusion, the present study demonstrated that SchB exerted inhibitory effects on large‑cell lung cancer cells via targeting the NF‑κB and p38 MAPK signaling pathways, suggesting that SchB may act as a potential therapeutic drug for large‑cell lung cancer.

The treatment of asthma using the Chinese Materia Medica

ETHNOPHARMACOLOGICAL RELEVANCE

Asthma is a costly global health problem that negatively influences the quality of life of patients. The Chinese Materia Medica (CMM) contains remedies that have been used for the treatment of asthma for millennia. This article strives to systematically summarize the current research progress so that more comprehensive examinations of various databases related to CMM anti-asthma drugs, can be performed, so as to sequentially provide effective basic data for development and application of anti-asthma drugs based on the CMM.

MATERIALS AND METHODS

The research data published over the past 20 years for asthma treatment based on traditional CMM remedies were retrieved and collected from libraries and online databases (PubMed, ScienceDirect, Elsevier, Spring Link, Web of Science, PubChem Compound, Wan Fang, CNKI, Baidu, and Google Scholar). Information was also added from classic CMM, literature, conference papers on classic herbal formulae, and dissertations (PhD or Masters) based on traditional Chinese medicine.

RESULTS

This review systematically summarizes the experimental studies on the treatment of asthma with CMM, covering the effective chemical components, typical asthma models, important mechanisms and traditional anti-asthma CMM formulae. The therapy value of the CMM for anti-asthma is clarified, and the original data and theoretical research foundation are provided for the development of new anti-asthmatic data and research for the CMM.

CONCLUSIONS

Substantial progress against asthma has been made through relevant experimental research based on the CMM. These advances improved the theoretical basis of anti-asthma drugs for CMM and provided a theoretical basis for the application of a asthma treatment that is unique. By compiling these data, it is expected that the CMM will now contain a clearer mechanism of action and a greater amount of practical data that can be used for future anti-asthma drug research.

Schizandrin attenuates inflammation induced by avian pathogenic Escherichia coli in chicken type II pneumocytes

Avian pathogenic Escherichia coli (APEC) is a kind of highly pathogenic parenteral bacteria, which adheres to chicken type II pneumocytes through pili, causing inflammatory damage of chicken type II pneumocytes. Without affecting the growth of bacteria, anti-adhesion to achieve anti-inflammatory effect is considered to be a new method for the treatment of multi-drug-resistant bacterial infections. In this study, the anti-APEC activity of schizandrin was studied in vitro. By establishing the model of chicken type II pneumocytes infected with APEC-O78, the adhesion number, the expression of virulence genes, the release of lactate dehydrogenase (LDH), levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8 and activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were detected. The results showed that schizandrin reduced the release of LDH and the adherence of APEC on chicken type II pneumocytes. Moreover, schizandrin markedly decreased the levels of IL-1β, IL-8, IL-6, and TNF-α, the mechanism responsible for these effects was attributed to the inhibitory effect of schizandrin on NF-κB and MAPK signaling activation. In conclusion, our findings revealed that schizandrin could reduce the inflammatory injury of chicken type II pneumocytes by reducing the adhesion of APEC-O78 to chicken type II pneumocytes. The results indicate that schizandrin can be a potential agent to treat inflammation caused by avian colibacillosis.

Schizandrin attenuates lung lesions induced by Avian pathogenic Escherichia coli in chickens

Avian pathogenic Escherichia coli (APEC) can cause serious pathological changes and inflammation in chickens. Schizandrin has anti-inflammatory activity and can prevent damage to various tissues and organs. The purpose of this study was to investigate the protective effect of schizandrin on APEC-induced lung lesions in chickens and explore the potential mechanism of schizandrin protection. The schizandrin (50, 100, and 200 mg/kg) was intragastrically administered for 3 days. APEC was administered using intraperitoneal (i.p.) injection to induce lung lesions. Then, chickens were sacrificed by CO2 inhalation 24 h later and the lung tissues were collected for examining histopathological changes, wet/dry (W/D) ratio, myeloperoxidase (MPO) activity, malondialdehyde (MDA), levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 and activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Our findings showed that schizandrin markedly inhibited pathological changes, pulmonary edema, MPO activity and MDA content. Moreover, schizandrin markedly reduced the levels of TNF-α, IL-1β, IL-6 and IL-8 in lung tissue. Importantly, the mechanism responsible for these effects was attributed to the inhibitory effect of schizandrin on NF-κB and MAPK signaling activation. In conclusion, our findings reveal that schizandrin displays anti-oxidant and anti-inflammatory activity against APEC-induced lung lesions in chickens, paving the way for rational use of schizandrin as a protective agent against lung-related inflammatory disease.

An experimental model of asthma in rats using ovalbumin and lipopolysaccharide allergens

Asthma is chronic and multi-factorial inflammatory disease hence single allergen induced asthma in an animal is not identical to clinical asthma. Therefore, we developed a novel experimental model of asthma in rats using ovalbumin (OVA) and lipopolysaccharide (LPS) allergens. Rats were divided into four groups; normal (NC), OVA, LPS, and OVA-LPS treated. Rats were sensitized with OVA (100 μg/kg, adsorbed in 100 mg/mL aluminum hydroxide, i.p.), LPS (10 μg/kg, i.p.) and both (OVA-LPS) on 7^th, 14^th, 21^st days and was followed by challenge with OVA (1%w/v), LPS (1%w/v), OVA (0.5%w/v) and LPS (0.5%w/v) for 30 min thrice/week for three weeks in the OVA, LPS and OVA-LPS groups, respectively. On 41 day, lung function parameters (respiration rate, tidal volume, and airflow rate), total and differential leukocytes count in the blood as well as BALf and inflammatory cytokines (IL-4, IL-5, and IL-13) in serum were measured. Histology of lungs was performed.

The results suggested that the tidal volume and airflow rate were significantly decreased while respiration rate, total and differential leukocytes count in blood as well as BALf and serum cytokines level were significantly increased in the OVA-LPS as compared to NC, OVA, and LPS.

In conclusion, the combination of OVA and LPS induced phenotypes of severe asthma with eosinophilic, neutrophilic and lymphocytic inflammation.

Dose dependence and durability of the therapeutic effects of Asparagus cochinchinensis fermented extract in an ovalbumin-challenged asthma model

The butanol extract of Asparagus cochinchinensis roots fermented with Weissella cibaria (BAfW) significantly suppressed the inflammatory response induced by lipopolysaccharide (LPS) treatment in RAW264.7 cells. To investigate the dose dependence and durability of BAfW on the anti-asthma effects, alterations in key parameters were measured in ovalbumin (OVA)-challenged Balb/c mice treated with the different doses of BAfW at three different time points. The number of immune cells, OVA-specific IgE level, thickness of respiratory epithelium and mucus score decreased significantly in a dose-dependent manner in response to treatment with 125 to 500 mg/kg BAfW (P<0.05), although the highest level was detected in the 500 mg/kg treated group. Moreover, the decrease in these parameters was maintained from 24 to 48 h in the 500 mg/kg of BAfW treated group. At 72 h, the effects of BAfW on the number of immune cells, OVA-specific IgE level and thickness of respiratory epithelium partially disappeared. Overall, this study provides the first evidence that the anti-asthma effect of BAfW may reach the maximum level in OVA-challenged Balb/c mice treated with 500 mg/kg and that these effects can last for 48 h.

Fluoxetine protects against OVA induced bronchial asthma and depression in rats

Depression is very common in asthmatic patients and may increases risk for morbidity and mortality. The present work aimed to investigate the protective effect of fluoxetine, on behavioral and biochemical changes, associated with ovalbumin (OVA) - induced bronchial asthma and depression in rats. Rats were sensitized with intraperitoneal administration of OVA plus aluminum hydroxide for 3 consecutive days then at day 11 followed by OVA intranasal challenge at days 19, 20, 21. Rats were either pretreated with dexamethasone, fluoxetine10mg/kg or fluoxetine 20 mg/kg. At the end of the experiment, various tests were performed, including open field, forced swimming and respiratory function tests. Blood was drawn for serum IgE detection. Finally, rats were euthanized, brain-derived neurotrophic factor (BDNF) was estimated in bronchoalveolar lavage (BAL) fluid and lung content of reduced glutathione (GSH), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α) and interleukin 4 (IL-4) were determined. Histopathological study was also performed. The results showed that fluoxetine significantly ameliorated OVA- induced biochemical and behavioral changes. Fluoxetine may protect against OVA-induced asthma and depression in rats. This effect may be mediated at least in part by its antioxidant, anti-inflammatory and immunosuppressant effect.

Schisandrin Attenuates Lipopolysaccharide-Induced Lung Injury by Regulating TLR-4 and Akt/FoxO1 Signaling Pathways

Objective: Acute lung injury is a severe clinic condition with limited therapeutic approaches. This study evaluated whether schisandrin (Sch), an ingredient of Schisandra chinensis, has preventive effects on endothelium and epithelium injury induced by lipopolysaccharide (LPS) and the underlying mechanisms.

Methods: Male Wistar rats were continuously infused with LPS (5 mg/kg/h) via the left jugular vein for 90 min. In some rats, Sch (2.5 mg/kg/h) was administrated through the left jugular vein 30 min before LPS infusion. Leukocyte recruitment, levels of inflammatory cytokines, lung histology and edema, vascular and alveolar barrier disruption and related proteins were evaluated at indicated time point after LPS challenge.

Results: LPS infusion for 90 min resulted in an increased leukocyte adhesion to pulmonary venules and overproduction of cytokine and chemokine in both serum and lung homogenate. At 8 h after termination of LPS infusion, obvious Evans blue extravasation and lung edema were observed, along with an increased apoptosis, a decreased expression of tight junction and adherent junction proteins, and a reduction in von Willebrand factor (vWF) and keratin, all of which were attenuated by Sch treatment. Meanwhile, the LPS-elicited activation of TLR-4/NF-κB/MAPK and FoxO1 signaling was inhibited by Sch.

Conclusion: The present study revealed that pretreatment with Sch alleviated lung endothelium and epithelium injury after LPS stimulation, which is attributable to inhibition of cell injury and activation of cell regeneration via regulation of TLR-4/NF-κB/MAPK and Akt/FoxO1 signaling pathway.

Establishment of different experimental asthma models in mice

Asthma is a complex disease. The heterogeneity of airway inflammation during asthma indicates there are different mechanisms involved. In order to further study the mechanisms of asthma, different mouse models were established to mimic corresponding subtypes of asthma in clinic. Eosinophilic asthma was established by intraperitoneal injections of ovalbumin (OVA) on day 0 and day 7, followed by inhalation of aerosolized OVA on days 14–17. Neutrophilic asthma was established by transtracheal administration of a high dose of lipopolysaccharide (LPS; 10 µg) on days 15 and 17 in combination with OVA sensitization and challenge as described previously. Mix-granulocytic asthma was established by transtracheal administration of a low dose of LPS (1 µg) on day 15, in combination with OVA sensitization and challenge as described previously. Compared with healthy controls, increased numbers of eosinophils, elevated levels of T helper (Th)2 cytokines in bronchoalveolar lavage fluid (BALF), and moderated inflammation of lung tissues was observed in eosinophilic asthma. Increased numbers of neutrophils, elevated levels of Th1 and Th17 cytokines in BALF and severe inflammation of lung tissues was observed in neutrophilic asthma. Increased numbers of both eosinophils and neutrophils, elevated levels of Th1, Th2 and Th17 cytokines in BALF and severe inflammation of lung tissues was observed in mix-granulocytic asthma. Airway hyperresponsiveness, increased bronchial mucus secretion, and elevated serum levels of immunoglobin (Ig)E and OVA-IgE were detected in all three asthma models. Dexamethasone reduced the pathogenic symptoms of the mice in eosinophilic asthma, however had no effect on neutrophilic asthma or mix-granulocytic asthma. Each model of asthma established in the present study represents corresponding subtypes of asthma in clinic.

Schisandrin B down-regulated lncRNA BCYRN1 expression of airway smooth muscle cells by improving miR-150 expression to inhibit the proliferation and migration of ASMC in asthmatic rats

OBJECTIVE

The mechanism of Schisandrin B on the proliferation and migration of airway smooth muscle cells (ASMCs) in asthmatic rats was explored.

METHODS

SD rats were divided into three groups: control (group 1), model (group 2) and model + Schisandrin B (group 3). miR-150 and lncRNA BCYRN1 levels were measured by qRT-PCR. The combination of BCYRN1 and miR-150 was detected by RNA pull down. ASMCs' viability/proliferation/migration were examined by WST-1 assay and 24-well Transwell system.

RESULTS

Schisandrin B up-regulated miR-150 expression and down-regulated BCYRN1 expression in sensitized rats. Schisandrin B reversed the expression of miR-150 and BCYRN1 in MV-treated ASMCs. In addition, Schisandrin B inhibited the viability, proliferation and migration of MV-induced ASMCs. We also found miR-150 inhibited BCYRN1 expression which was proved by experiments using ASMCs transfected with miR-150 inhibitor.

CONCLUSION

Schisandrin B increased miR-150 expression and decreased BCYRN1, and BCYRN1 expression was inhibited by miR-150, which indicated that Schisandrin B could regulate BCYRN1 through miR-150.

[Effects of vasoactive intestinal peptide on airway inflammation and Th17/Treg balance in asthmatic mice]

OBJECTIVE

To investigate the effects of vasoactive intestinal peptide (VIP) on the airway inflammation and its regulatory effect on Th17/Treg imbalance in asthmatic mice.

METHODS

A total of 30 BALB/c mice were equally and randomly divided into three groups: control, asthma, and VIP. An acute asthmatic mouse model was established by sensitization and challenge with ovalbumin (OVA). The control group received normal saline instead of OVA. Before the challenge with OVA, the VIP group was administered VIP (20 μg/mL) by aerosol inhalation for 30 minutes. The bronchoalveolar lavage fluid (BALF) and the lung tissue were collected from mice. The pathological changes in the lung tissue were observed by hematoxylin and eosin staining. The levels of Th17/Treg-related cytokines in BALF were measured by enzyme-linked immunosorbent assay. The expression of retinoid-related orphan receptor gamma t (RORγt) and forkhead box P3 (Foxp3) were measured by real-time fluorescence quantitative PCR and immunohistochemistry.

RESULTS

The histopathological results showed that the VIP group had milder symptoms of airway inflammation than the asthma group. The level of IL-17 in BALF in the asthma group was significantly higher than that in the control group and the VIP group (P<0.01), but the level of IL-17 in the control group was significantly lower than that in the VIP group (P<0.01). The level of IL-10 in BALF in the asthma group was significantly lower than that in the control group and the VIP group (P<0.01, but the level of IL-10 in the VIP group was significantly higher than that in the control group (P<0.01). The asthma group showed significantly higher expression levels of RORγt mRNA and protein in the lung tissue and significantly lower expression levels of Foxp3 mRNA and protein than the control group (P<0.01). The VIP group had significantly lower expression levels of RORγt mRNA and protein in the lung tissue and significantly higher expression levels of Foxp3 mRNA and protein than the asthma group (P<0.05).

CONCLUSIONS

The Th17/Treg imbalance may be closely related to the airway inflammation in asthmatic mice. VIP can improve airway inflammation by regulating the Th17/Treg imbalance in asthmatic mice.

Schisandra chinensis and Its Main Constituent Schizandrin Attenuate Allergic Reactions by Down-Regulating Caspase-1 in Ovalbumin-Sensitized Mice

Schisandra chinensis (SC) and its main constituent, schizandrin (SCH) exhibit anti-inflammatory and anti-allergic activities. Allergic and inflammatory reactions are aggravated via caspase-1 signaling pathway. However, the regulatory effects of SC and SCH on caspase-1 activation have not been clarified yet. In this study, we aimed to clarify the anti-allergic effects of SC and SCH using an ovalbumin (OVA)-sensitized mice and anti-CD3 and anti-CD28 antibodies-stimulated splenocytes. SC or SCH significantly inhibited the levels of immunoglobulin (Ig)E, IgG1, or interleukin (IL)-4 in serum of OVA-sensitized mice. SC or SCH significantly inhibited the levels of IL-6, tumor necrosis factor (TNF)-[Formula: see text], and IL-1[Formula: see text] in spleen of the OVA-sensitized mice. SC or SCH significantly suppressed the expression of caspase-1 and receptor-interacting protein (RIP)-2 in spleen of the OVA-sensitized mice. In activated splenocytes, SC or SCH significantly decreased the expression of caspase-1 and RIP-2 as well as the production of IL-6 and TNF-[Formula: see text]. We suggest that SC and SCH exert an anti-allergic effect by down-regulating caspase-1 signaling.

Pistacia integerrima ameliorates airway inflammation by attenuation of TNF-α, IL-4, and IL-5 expression levels, and pulmonary edema by elevation of AQP1 and AQP5 expression levels in mouse model of ovalbumin-induced allergic asthma

BACKGROUND

Natural products are considered as an essential source for the search of new drugs. Pistacia integerrima galls (PI) have been used for the treatment of asthma and cough in traditional system of medicine.

AIM/HYPOTHESIS

Current study investigates the immunomodulatory and anti-inflammatory activities of P. integerrima in mouse model of ovalbumin-induced allergic asthma.

METHODS

Mice were intraperitoneally sensitized and subsequently challenged intranasally with ovalbumin to induce allergic asthma. Experimental group mice were treated with methanol extract of P. integerrima extract (200mg/kg b. w.) and Methylprednisolone (MP) (15mg/kg b. w.) for 07 consecutive days, alongside intranasal challenge. Lung tissues were stained with Hematoxyline and Eosin (H & E), and Periodic Acid-Schiff (PAS) stains for histopathological evaluation. Lung wet/dry weight ratio was measured as an index of lung tissue edema. Albumin was injected in the right ear 24h before sacrificing the mice and difference of weight was taken as a degree of delayed type hypersensitivity (DTH). mRNA expression levels of TNF-α, IL-4, IL-5, Aquaporin-1 (AQP1), and AQP5 were evaluated using reverse transcription polymerase chain reaction (RT-PCR) followed by gel electrophoresis.

RESULTS

The data showed both PI extract and MP significantly alleviated DTH and nearly normalized total leukocyte count and differential leukocyte count in both blood and BALF. We found significantly suppressed goblet cell hyperplasia and inflammatory cell infiltration after treatment with both PI extract and MP. Expression levels of TNF-α, IL-4, and IL-5 were also found significantly reduced after treatment with both PI extract and MP, which might have resulted in the amelioration of airway inflammation. Current study displayed that both PI extract and MP significantly decreased lung wet/dry ratio, suggesting reduction in pulmonary edema. RT-PCR analysis showed significant increase in AQP1 and AQP5 expression levels after treatment with both PI extract and MP, which might have caused the alleviation of pulmonary edema.

CONCLUSION

Our study displays that P. integerrima possesses significant anti-asthmatic activity which may be attributed to reduction in TNF-α, IL-4, and IL-5 expression levels, and increase in AQP1 and AQP5 expression levels.

Schisandrin B inhibits the proliferation of airway smooth muscle cells via microRNA-135a suppressing the expression of transient receptor potential channel 1

Airway smooth muscle cell (ASMC) was known to involve in the pathophysiology of asthma. Schisandrin B was reported to have anti-asthmatic effects in a murine asthma model. However, the molecular mechanism involving in the effect of Schisandrin B on ASMCs remains poorly understood. Sprague-Dawley rats were divided into three groups: rats as the control (Group 1), sensitized rats (Group 2), sensitized rats and intragastric-administrated Schisandrin B (Group 3). The expression of miR-135a and TRPC1 was detected in the rats from three groups. Platelet-derived growth factor (PDGF)-BB was used to induce the proliferation of isolated ASMCs, and the expression of miR-135a and TRPC1 was detected in PDGF-BB-treated ASMCs. Cell viability was examined in ASMCs transfected with miR-135a inhibitor or si-TRPC1. The expression of TRPC1 was examined in A10 cells pretreated with miR-135a inhibitor or miR-135a mimic. In this study, we found that Schisandrin B attenuated the inspiratory and expiratory resistances in sensitized rats. Schisandrin B upregulated the mRNA level of miR-135a and decreased the expression of TRPC1 in sensitized rats. In addition, Schisandrin B reversed the expression of miR-135a and TRPC1 in PDGF-BB-induced ASMCs. Si-TRPC1 abrogated the increasing proliferation of ASMCs induced by miR-135a inhibitor. We also found that miR-135a regulated the expression of TRPC1 in the A10 cells. These results demonstrate that Schisandrin B inhibits the proliferation of ASMCs via miR-135a suppressing the expression of TRPC1.

Oxyresveratrol ameliorates allergic airway inflammation via attenuation of IL-4, IL-5, and IL-13 expression levels

AIM

Oxyresveratrol is known to possess anti-inflammatory property. Current study investigates the immunosuppressive effect of oxyresveratrol by using mouse model of ovalbumin (OVA)-induced allergic airway inflammation.

METHODS

BALB/c mice were randomly divided into five groups having 8 mice in each group. Treatment with low dose (7 mg/kg) and high dose (15 mg/kg) of oxyresveratrol, and methylprednisolone (15 mg/kg; standard drug) was started 2 week after immunization of mice with ovalbumin and continued for 7d. Ovalbumin was also injected into pinna of right ear 24h before sacrificing the mice to evaluate delayed type hypersensitivity (DTH). H&E and PAS staining were used for histopathological evaluation of lungs. Reverse transcription polymerase chain reaction followed by gel electrophoresis were used for evaluation of mRNA expression levels of IL-4, IL-5, and IL-13.

RESULTS

Oxyresveratrol significantly reduced total leucocyte count in both blood and bronchoalveolar lavage fluid (BALF). Treatment with oxyresveratrol normalized altered eosinophil and neutrophil counts in both blood and BALF. OVA-specific T-cell response was also significantly inhibited by oxyresveratrol. A significant attenuation of inflammatory cell infiltration and goblet cell hyperplasia was observed after treatment with oxyresveratrol. Data showed that oxyresveratrol significantly suppressed Th2 (T helper cells) type immune response which was obvious by the reduction in mRNA expression levels of IL-4, IL-5, and IL-13. Similarly, treatment with methylprednisolone also significantly reduced all the immunomodulatory and inflammatory parameters.

CONCLUSIONS

Our study demonstrates that oxyresveratrol ameliorates allergic asthma. The anti-asthmatic activity might in part occur via the down regulation of IL-4, IL-5, and IL-13 expression levels.

Anti-allergic effect of α-cubebenoate isolated from Schisandra chinensis using in vivo and in vitro experiments

AIM OF THE STUDY

In Oriental countries, the dried fruits of Schisandra chinensis are extensively used in traditional medicine to treat asthma, gonorrhea, and other diseases. Recently, α-cubebenoate was isolated as an anti-inflammatory component from Schisandra chinensis. In the present study, the authors examined the anti-allergic effect of α-cubebenoate using in vivo and in vitro experiments.

MATERIALS AND METHODS

α-Cubebenoate was isolated from an extract of Schisandra chinensis fruits. Antigen-induced degranulation and Ca(2+) mobilization were measured in RBL-2H3 mast cells. In addition, BALB/c mice were sensitized with ovalbumin and aluminum hydroxide, and then challenged with ovalbumin for three consecutive days. α-Cubebenoate (1mg/kg) was administered intraperitoneally 30min before each ovalbumin challenge.

RESULTS

In RBL-2H3 mast cells, α-cubebenoate inhibited antigen-induced degranulation and increase of intracellular Ca(2+) concentrations. In the ovalbumin-induced asthma model, α-cubebenoate suppressed bronchiolar structural changes induced by ovalbumin challenge. Furthermore, α-cubebenoate strongly inhibited accumulations of eosinophils, macrophages, and lymphocytes in bronchoalveolar lavage fluid. α-Cubebenoate also suppressed Th2 cytokines (IL-4 and IL-13) and TGF-β1 in lung tissues and in immune cells at the mRNA and protein levels.

CONCLUSION

α-Cubebenoate has an inhibitory effect on allergic inflammation and could be utilized as an agent for the treatment of asthma.

Schizandrin inhibits fibrosis and epithelial-mesenchymal transition in transforming growth factor-β1-stimulated AML12 cells

The transforming growth factor (TGF)-β1 plays a crucial role in the induction of the epithelial-to-mesenchymal transition (EMT) in hepatocytes, which contributes to the pathogenesis of liver fibrosis. The inhibition of the TGF-β1 cascade suppresses EMT and the resultant fibrosis. Schizandrin (Sch) has various therapeutic effects on a range of medical conditions such as anti-asthmatic, anti-cancer, and anti-inflammatory effects. However, the effect of Sch on TGF-β1-stimulated hepatic fibrosis and EMT is still unknown. In the present investigation, we evaluated the anti-fibrotic and anti-EMT properties of Sch and its underlying mechanisms in murine hepatocyte AML12 cells. Overall, we found that Sch inhibited the pro-fibrotic activity of TGF-β1 in AML12 cells; thus, it suppressed the accumulation of ECM proteins. Also, Sch inhibited the EMT as assessed by reduced expression of vimentin and fibronectin, and increased E-cadherin and ZO-1 in TGF-β1 induced AML12 cells. Sch reduced TGF-β1-mediated phosphorylation of Smad2/3 and Smad3/4 DNA binding activity. On the other hand, Sch reduced TGF-β1-induced ERK1/2 and PI3K/Akt phosphorylation in the non-Smad pathway. In conclusion, Sch can antagonize TGF-β1-mediated fibrosis and EMT in AML12 cells. Sch may possess potential as an anti-fibrotic molecule in the treatment of liver fibrosis.

Antidiabetic Effect of Schisandrae Chinensis Fructus Involves Inhibition of the Sodium Glucose Cotransporter

Preclinical Research Schisandrae Chinensis Fructus (SCF), the fruit of Schisandra chinensis (Turcz.) Baill. (family Schisandraceae) is traditionally used as a tonic and antidiabetic agent in Asia. In this study, SCF was investigated for its effects on sodium glucose cotransporters 1 and 2 (SGLT 1 and 2) expressed in a COS-7 cell line for its specificity in inhibiting SGLT2, which is a novel mechanism to screen for potential antidiabetic agents. Using a bioassay-guided fractionation, we then tried to isolate and identify the active fraction(s)/component(s). The ethanol extract of SCF at a concentration of 1 mg/mL significantly inhibited 89% of SGLT1 and 73% of SGLT2 activities in a [¹⁴ C]-α-methyl-d-glucopyranoside ([¹⁴ C]-AMG) uptake assay. Fractionation of the ethanol extract yielded nine fractions, of which F8, at a concentration of 1 mg/mL, was specific in inhibiting SGLT 2 (42% inhibition, P < 0.001), without inhibiting SGLT 1. Using LC/MS-MS, three compounds, deoxyschisandrin, schisandrin B (γ-schisandrin) and schisandrin were identified in F8 and their amounts quantified. However, subsequent evaluation in the [¹⁴ C]-AMG uptake assay showed that these three compounds failed to inhibit SGLT 2 activity indicating that the SGLT active component(s) from SCF have yet to be identified. Drug Dev Res 76 : 1-8, 2015.

Basophils as a primary inducer of the T helper type 2 immunity in ovalbumin-induced allergic airway inflammation

Antigen-induced allergic airway inflammation is mediated by T helper type 2 (Th2) cells and their cytokines, but the mechanism that initiates the Th2 immunity is not fully understood. Recent studies show that basophils play important roles in initiating Th2 immunity in some inflammatory models. Here we explored the role of basophils in ovalbumin (OVA) -induced airway allergic inflammation in BALB/c mice. We found that OVA sensitization and challenge resulted in a significant increase in the amount of basophils in blood and lung, along with the up-regulation of activation marker of CD200R. However, depletion of basophils with MAR-1 or Ba103 antibody attenuated airway inflammation, represented by the significantly decreased amount of the Th2 subset in spleen and draining lymph nodes, interlukin-4 level in lung and OVA-special immunoglobulin E (sIgE) levels in serum. On the other hand, adoptive transfer of basophils from OVA-challenged lung tissue to naive BALB/c mice provoked the Th2 immune response. In addition, pulmonary basophils from OVA-challenged mice were able to uptake DQ-OVA and express MHC class II molecules and CD40 in vivo, as well as to release interleukin-4 following stimulation by IgE-antigen complexes and promote Th2 polarization in vitro. These findings demonstrate that basophils may participate in Th2 immune responses in antigen-induced allergic airway inflammation and that they do so through facilitating antigen presentation and providing interleukin-4.

Icariin attenuates glucocorticoid insensitivity mediated by repeated psychosocial stress on an ovalbumin-induced murine model of asthma

Evidence shows that psychosocial stress exacerbates asthma, but there is little intervention to alleviate negative effects of psychosocial stress on asthma. We investigated the role of icariin in anti-inflammation and anti-anxiety potential in a murine model combined psychosocial stress with allergic exposure. The results indicated that icariin administered remarkable increased activity in the center of the open field, reversed airway hyperresponsivenesss, reduced inflammatory cytokine infiltration to the lung and whole body and also in part recovered glucocorticoid responsiveness. Furthermore, our data also showed that icariin significantly inhibited increases of corticosterone and markedly increased glucocorticoid receptor mRNA and protein expression in the lungs of mice exposed to both stress and allergen. Collectively, we speculate that inducing glucocorticoid receptor modulation might be the potential mechanisms of icariin to facilitate corticosteroid responsiveness of cytokine production.

Dihydroartemisinin suppresses ovalbumin-induced airway inflammation in a mouse allergic asthma model

Asthma is a complex disease characterized by reversible airway obstruction, airway hyper-responsiveness (AHR) and chronic inflammation of the airways. Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin isolated from the traditional Chinese herb Artemisia annua, has been shown to possess antimalarial and antitumor activities, but whether it can be used in asthma treatment has not been investigated. In this study, we attempted to determine whether DHA regulates inflammatory mediators in the ovalbumin (OVA)-induced mouse asthma model. BALB/c mice were sensitized and challenged by OVA to induce chronic airway inflammation. The intragastrical administration of DHA at 30 mg/kg significantly decreased the number of infiltrating inflammatory cells, T-helper type 2 (Th2) cytokines, OVA-specific immunoglobulin E (IgE) and AHR. Treatment with DHA also attenuated OVA-induced mRNA expression of Muc5ac and chitinase 3-like protein 4 (Ym2) in lung tissues. In addition, lung histopathological studies revealed that DHA inhibited inflammatory cell infiltration and mucus hypersecretion. Then signal transduction studies showed that DHA significantly inhibited extracellular signal-regulated protein kinase (ERK), p38 mitogen-activated protein kinase phosphorylation. DHA also inhibited nuclear factor-κB (NF-κB) activation via the inhibition of phosphorylation of IκBα. These findings provide new insight into the immunopharmacological role of DHA in terms of its effects in a mouse model of asthma.

Effects of schizandrin on the expression of thymic stromal lymphopoietin in human mast cell line HMC-1

AIMS

Thymic stromal lymphopoietin (TSLP) plays an important role in allergic diseases such as asthma and atopic dermatitis. Schizandrin has various effects such as anti-asthmatic, anti-cancer and anti-inflammatory effects. However, the effect of schizandrin on the production of TSLP has not been clarified. Thus, we investigated how schizandrin inhibits the production of TSLP in the human mast cell line HMC-1 cells.

MAIN METHODS

We used enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction, luciferase assay, and Western blot analysis to investigate the effects of schizandrin.

KEY FINDINGS

Schizandrin inhibited the production and mRNA expression of TSLP in HMC-1 cells. The maximal inhibition rate of TSLP production by schizandrin (10 μM) was 68.62 ± 3.47%. Schizandrin inhibited the translocation and luciferase activity of nuclear factor-κB induced by phorbol myristate acetate plus A23187. In the activated HMC-1 cells, the activation of caspase-1 was increased, whereas the activation of caspase-1 was decreased by pretreatment with schizandrin.

SIGNIFICANCE

These results suggest that schizandrin can be used to treat inflammatory and atopic diseases through the inhibition of TSLP.

Sitagliptin exerts anti-inflammatory and anti-allergic effects in ovalbumin-induced murine model of allergic airway disease

Sitagliptin, a new oral glucose lowering medication, is used for treatment of type 2 diabetes mellitus. The anti-inflammatory property of sitagliptin is reported, yet no studies have been done on asthma. In the present study, the effect of sitagliptin on allergic asthma was investigated using ovalbumin (OVA)-induced asthma model in mice. Swiss male albino mice sensitized and challenged to ovalbumin were treated with sitagliptin (8 mg/kg administered orally twice a day). Drug treatment was done on each day from days 16 to 23, 1 h before the challenge on the days of challenge. Sitagliptin treatment markedly decreased inflammatory cell accumulation in bronchoalveolar lavage (BAL) fluid and in the lungs, as revealed by histopathological examination. Furthermore, the levels of interleukin (IL)-13 in BAL fluid, total and OVA specific immunoglobulins (Ig)-E in serum, were significantly reduced as compared to the OVA group. In addition, sitagliptin significantly increased superoxidase dismutase (SOD) and reduced glutathione (GSH) activities with significant decrease in malondialdehyde (MDA) content in the lung. Importantly, sitagliptin decreased mRNA expression of the inflammatory cytokines tumor necrosis factor-α (TNF-α) and transforming growth factor-β(1) (TGF-β(1)) in lung tissues as compared to the OVA group. Moreover, nitric oxide content as well as the mRNA expression of inducible nitric oxide synthase (iNOS) was remarkably decreased by sitagliptin treatment. Sitagliptin attenuates the allergic airway inflammation suggesting that sitagliptin may have applications in the treatment of bronchial asthma.

Kochia scoparia fruit attenuates allergic airway inflammation in ovalbumin (OVA)-induced murine asthma model

Kochia scoparia fruit has been used in Asia for a long time. It possesses anti-inflammatory, antiallergic, and antipruritic actions. We investigated the role of a K. scoparia fruit ethanolic extract (KSEE) in allergic airway inflammation in a mouse asthma model. BALB/c mice were sensitized with ovalbumin (OVA) and, upon OVA aerosol challenge, developed airway eosinophilia, mucus hypersecretion, elevations in cytokine, chemokine, and immunoglobulin levels, and upregulation of MMP-9, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) expression. Intragastric administration of KSEE significantly attenuated OVA-induced influx of total leukocytes, eosinophils, neutrophils, macrophages, and lymphocytes into lungs, as well as attenuating levels of interleukin (IL)-4 and IL-5 in a dose-dependent manner. KSEE also significantly reduced the serum levels of total and OVA-specific immunoglobulin (Ig)E and OVA-specific IgG1 release into the airspace. Histological studies showed that KSEE inhibited OVA-induced lung tissue eosinophilia and airway mucus production. Moreover, in whole lung tissue lysates, immunoreactivity showed that KSEE markedly attenuated the OVA-induced increase in expression of ICAM-1, VCAM-1, and MMP-9. These results show that KSEE possesses protective effects against allergic airway inflammation, acts as an MMP-9 inhibitor, and induces a reduction in ICAM-1 and VCAM-1 expression.