Puerarin attenuates airway inflammation by regulation of eotaxin-3

Phytochemicals as treatment for allergic asthma: Therapeutic effects and mechanisms of action

BACKGROUND

Allergic asthma is an inflammatory disease caused by the immune system's reaction to allergens, inflammation and narrowing of the airways, and the production of more than normal mucus. One of the main reasons is an increased production of inflammatory cytokines in the lungs that leads to the appearance of symptoms of asthma, including inflammation and shortness of breath. On the other hand, it has been proven that phytochemicals with their antioxidant and anti-inflammatory properties can be useful in improving allergic asthma.

PURPOSE

Common chemical treatments for allergic asthma include corticosteroids, which have many side effects and temporarily relieve symptoms but are not a cure. Therefore, taking the help of natural compounds to improve the quality of life of asthmatic patients can be a valuable issue that has been evaluated in the present review.

STUDY DESIGN AND METHODS

In this study, three databases (Scopus, PubMed, and Cochrane) with the keywords: allergic asthma, phytochemical, plant, and herb were evaluated. The primary result was 5307 articles. Non-English, repetitive, and review articles were deleted from the study.

RESULTS AND DISCUSSION

Finally, after carefully reading the articles, 102 were included in the study (2006-2022). The results of this review state that phytochemicals suppress the inflammatory pathways via inhibition of inflammatory cytokines production/secretion, genes, and proteins involved in the inflammation process, reducing oxidative stress indicators and symptoms of allergic asthma, such as cough and mucus production in the lungs.

CONCLUSION

With their antioxidant effects, this study concluded that phytochemicals suppress cytokines and other inflammatory indicators and thus can be considered an adjunctive treatment for improving allergic asthma.

CX3CR1+ Macrophage Facilitates the Resolution of Allergic Lung Inflammation via Interacting CCL26

Rationale: The resolution of inflammation is an active process coordinated by mediators and immune cells to restore tissue homeostasis. However, the mechanisms for resolving eosinophilic allergic lung inflammation triggered by inhaled allergens have not been fully elucidated. Objectives: Our objectives were to investigate the cellular mechanism of tissue-resident macrophages involved in the resolution process of eosinophilic lung inflammation. Methods: For the study, we used the institutional review board-approved protocol for human subsegmental bronchoprovocation with allergen, mouse models for allergic lung inflammation, and novel transgenic mice, including a conditional CCL26 knockout. The samples were analyzed using mass cytometry, single-cell RNA sequencing, and biophysical and immunological analyses. Measurements and Main Results: We compared alveolar macrophage (AM) subsets in the BAL before and after allergen provocation. In response to provocation with inhaled allergens, the subsets of AMs are dynamically changed in humans and mice. In the steady state, the AM subset expressing CX3CR1 is a relatively small fraction in bronchoalveolar space and lung tissue but drastically increases after allergen challenges. This subset presents unique patterns of gene expression compared with classical AMs, expressing high C1q family genes. CX3CR1+ macrophages are activated by airway epithelial cell-derived CCL26 via a receptor-ligand interaction. The binding of CCL26 to the CX3CR1+ receptor induces CX3CR1+ macrophages to secrete C1q, subsequently facilitating the clearance of eosinophils. Furthermore, the depletion of CX3CR1 macrophages or CCL26 in airway epithelial cells delays the resolution of allergic lung inflammation displaying prolonged tissue eosinophilia. Conclusions: These findings indicate that the CCL26-CX3CR1 pathway is pivotal in resolving eosinophilic allergic lung inflammation.

Natural isoflavone formononetin inhibits IgE-mediated mast cell activation and allergic inflammation by increasing IgE receptor degradation

Immunoglobulin (Ig)E-associated mast cell (MC) activation triggers pro-inflammatory signals that underlie type I allergic diseases. Here, we examined the effects of the natural isoflavone formononetin (FNT) on IgE-mediated MC activation and associated mechanisms of high-affinity IgE receptor (FcεRI) signal inhibition. The effects of FNT on the mRNA expression of inflammatory factors, release of histamine and β-hexosaminidase (β-hex), and expression of signaling proteins and ubiquitin (Ub)-specific proteases (USPs) were analyzed in two sensitized/stimulated MC lines. FcεRIγ-USP interactions were detected by co-immunoprecipitation (IP). FNT dose-dependently inhibited β-hex activity, histamine release, and inflammatory cytokine expression in FcεRI-activated MCs. FNT suppressed IgE-induced NF-κB and MAPK activity in MCs. The oral administration of FNT attenuated passive cutaneous anaphylaxis (PCA) reactions and ovalbumin (OVA)-induced active systemic anaphylaxis (ASA) reactions in mice. FNT reduced the FcεRIγ chain expression, via increased proteasome-mediated degradation, and induced FcεRIγ ubiquitination by inhibiting USP5 and/or USP13. FNT and USP inhibition may be useful for suppressing IgE-mediated allergic diseases.

Reversal of NADPH Oxidase-Dependent Early Oxidative and Inflammatory Responses in Chronic Obstructive Pulmonary Disease by Puerarin

In the present study, we investigated effects of Puerarin on the early oxidative and inflammatory responses in the lung triggered by acute cigarette smoking (ACS). C57BL/6 mice were exposed to ACS for 1 hr in the presence or absence of Puerarin and harvested at 2, 6, and 24 hours. ACS induced significant increases in superoxide production in mouse lungs at 2 and 6 hours; and superoxide production was also elevated in a time and concentration dependent manner in cigarette smoke extract (CSE) stimulated human small airway epithelial cells (HSAECs), which was dose-dependently abrogated by Puerarin. ACS exposure upregulated NOX1, NOX2, and NOX4 protein expression in mouse lungs. Likewise, NOX1 and NOX4 were upregulated in CSE-stimulated HSAECs. These responses were significantly or completely attenuated by Puerarin. ACS induced significant infiltrations of neutrophils and macrophages in mouse lung parenchyma and BAL fluid, which were completely or significantly abrogated by Puerarin, so was the activation of the NF-кB pathway and the upregulation in inflammatory mediators including TNF-α, KC (murine homolog of IL-8), COX-2, IL-6 and MCP-1. Nuclear translocation of p65, IL-8 secretion, and upregulation of COX-2 in CSE stimulated HSAECs were also markedly attenuated by Puerarin. Moreover, ACS or CSE stimulated upregulation in reactive oxygen species (ROS) production and expression of inflammatory mediators were alleviated by ROS scavenger TEMPO in vivo and vitro, with no synergy combining with Puerarin, indicating that the effects of Puerarin are redox-sensitive following activation of NOX. In summary, our data for the first time demonstrate that Puerarin robustly attenuates NOX isoform-dependent ROS production and inflammatory activation in ACS exposed mice and CSE treated HSAECs, indicating that Puerarin might be used as a robust therapeutic agent for early or early stage COPD.

Puerarin attenuates cisplatin-induced apoptosis of hair cells through the mitochondrial apoptotic pathway

Puerarin, one of the main components of Pueraria lobata, has been reported to possess a wide range of pharmacological activities, including anti-inflammatory, antioxidative and anti-apoptotic effects. However, the role of puerarin in ototoxic drug-induced hair cell injury has not been well characterized. This study explored whether puerarin protects against cisplatin-induced hair cell damage and its potential mechanisms. The viability of puerarin-treated HEI-OC1 cells was assessed by CCK8 assay. Reactive oxygen species (ROS) was estimated with flow cytometric analysis using Cellrox Green fluorescent probe. Apoptosis-related protein levels were detected by western blot analysis. Immunostaining of the organ of Corti was performed to determine mice cochlear hair cell survival. Our results showed that puerarin improved cell viability and suppressed apoptosis in the cisplatin-damaged HEI-OC1 cells and cochlear hair cells. Mechanistic studies revealed that puerarin attenuated mitochondrial apoptosis pathway by regulating apoptotic related proteins, such as Bax and cleaved caspase-3, and attenuated ROS accumulation after cisplatin damage. Moreover, puerarin was involved in regulating the Akt pathway in HEI-OC1 cells in response to cisplatin. Our results demonstrated that puerarin administration decreased the sensitivity to apoptosis dependent on the mitochondrial apoptotic pathway by reducing ROS generation, which could be used as a new protective agent against cisplatin-induced ototoxicity.

Pectin-zein based stigmasterol nanodispersions ameliorate dextran sulfate sodium-induced colitis in mice

Due to the insolubility of phytosterols in both water and oil, their application in the medicine and health and food industries is limited. In this study, zein and pectin were selected as wall materials of phytosterol nanoparticles to enhance the solubility and bioactivity of phytosterols. The colitis-inhibitory effects of zein-based stigmasterol nanodispersions (ZNs) and zein/pectin-based stigmasterol nanodispersions (ZPNs) were investigated in the sodium dextran sulfate (DSS)-induced colitis mouse model. The results showed that ZPNs' therapeutic effect was better than that of ZNs. According to electron microscopy observation, pectin adsorbed on the surface of zein appeared to form an elastic network structure, which increased the stability of stigmasterol nanodispersions. ZPNs not only relieved the adverse physiological symptoms of colitis in mice, but additionally prevented colonic length shortening and reduced fecal hemoglobin content. Immunohistochemical analysis showed that ZPNs could alleviate colitis by inhibiting the NF-κB signaling pathway involved in the expression of inflammatory factors TNF-α, IL-6, IL-1β, CSF-1 and coenzyme COX-2. This study suggests that supplement of nano-embedded stigmasterol based on zein and pectin has a positive therapeutic effect on alleviating colitis in mice. Such activities of nano-embedded stigmasterol in humans remain to be investigated.

Potential therapeutic interventions of plant-derived isoflavones against acute lung injury

Acute lung injury (ALI) is a life-threatening syndrome that possibly leads to high morbidity and mortality as no therapy exists. Several natural ingredients with negligible adverse effects have recently been investigated to possibly inhibit the inflammatory pathways associated with ALI at the molecular level. Isoflavones, as phytoestrogenic compounds, are naturally occurring bioactive compounds that represent the most abundant category of plant polyphenols (Leguminosae family). A broad range of therapeutic activities of isoflavones, including antioxidants, chemopreventive, anti-inflammatory, antiallergic and antibacterial potentials, have been extensively documented in the literature. Our review exclusively focuses on the possible anti-inflammatory, antioxidant role of botanicals'-derived isoflavones against ALI and their immunomodulatory effect in experimentally induced ALI. Despite the limited scope covering their molecular mechanisms, isoflavones substantially contributed to protecting from ALI via inhibiting toll-like receptor 4 (TLR4)/Myd88/NF-κB pathway and subsequent cytokines, chemokines, and adherent proteins. Nonetheless, future research is suggested to fill the gap in elucidating the protective roles of isoflavones to alleviate ALI concerning antioxidant potentials, inhibition of the inflammatory pathways, and associated molecular mechanisms.

Lactic Acid Bacteria and Natural Product Complex Ameliorates Ovalbumin-Induced Airway Hyperresponsiveness in Mice

The incidence of respiratory diseases, such as asthma, has substantially increased in recent times owing to environmental changes, such as air pollution. Induction of a chronic inflammatory response begins with production of biologically active mediators from the airway epithelium, which attracts and recruits inflammatory cells into the lung airway. In our previous study, we confirmed that Lactobacillus casei HY2782 and Bifidobacterium animalis spp. lactis HY8002 could improve lung inflammation in the COPD animal model. In this study, we investigated the effect of the HY2782 complex against airway hyperresponsiveness by using an ovalbumin (OVA)-induced animal model. An orally administered HY2782 complex on OVA-induced allergic asthma in a BALB/c mouse model was used. The present results showed that the HY2782 complex suppressed total immunoglobulin E in serum and bronchoalveolar lavage fluid (BALF). The cytokine production profile in BALF and serum revealed that the HY2782 complex showed reduced levels of Th2 cytokines among immune factors released due to the elevated allergic response. Levels of inflammatory mediators in BALF, MCP-1, MIP-2, and CXCL-9 were decreased by oral administration of the HY2782 complex. Lower numbers of eosinophils and neutrophils in BALF suggested that inflammation was ameliorated by the HY2782 complex. Histological observation of lung sections also showed infiltration of fewer cells. From results, we suggested that the HY2782 complex effectively responds to improvement of the immune response and airway hypersensitivity reaction because of the anti-inflammatory effect of the Pueraria lobata root extract and antioxidant effect of HY2782.

Protective effect of puerarin against burn-induced heart injury in rats

The present study evaluated the potential protective effects of puerarin and its associated mechanism on burn-induced myocardial damage. A total of 40 healthy adult Wistar rats were randomly divided into four groups: i) Sham; ii) burn; iii) burn + puerarin; and iv) puerarin. Serum levels of interleukin (IL)-1β, tumor necrosis factor-α (TNF-α) and IL-6 were measured using ELISA. Myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels were determined in myocardial homogenates using a commercial assay kit. TUNEL staining and western blot analysis of cleaved and pro-caspase-3 were also performed to assess apoptosis. Activation of p38-MAPK, ERK, JNK and AKT were measured using western blot analysis. Left ventricular systolic pressure, maximum rates of increase/decrease in left ventricular pressure, creatine kinase MB activity and cardiac troponin T levels were found to be altered in the burn group 12 h after burn, which were reversed by puerarin treatment. Injection of puerarin following burn injury also reduced heart water content. Serum levels of IL-1β, TNF-α and IL-6 were significantly higher in the burn group compared with those in the sham group. Puerarin treatment reduced serum levels of IL-1β, TNF-α and IL-6, in addition to reducing MPO activity and MDA levels in myocardial tissues. Puerarin inhibited the activation of caspase-3, p38, ERK and JNK following severe burn, but elevated Akt activation following severe burn. In conclusion, puerarin improved cardiac function in rats following severe burn injury, which may be due to reduced myocardial injury, inhibition of cardiomyocyte apoptosis and reduced oxidative inflammatory stress; the MAPK and AKT signaling pathways are proposed to the underlying mechanism of these findings.

Unraveling the Molecular Mechanism of Traditional Chinese Medicine: Formulas Against Acute Airway Viral Infections as Examples

Herbal medicine, including traditional Chinese medicine (TCM), is widely used worldwide. Herbs and TCM formulas contain numerous active molecules. Basically, they are a kind of cocktail therapy. Herb-drug, herb-food, herb-herb, herb-microbiome, and herb-disease interactions are complex. There is potential for both benefit and harm, so only after understanding more of their mechanisms and clinical effects can herbal medicine and TCM be helpful to users. Many pharmacologic studies have been performed to unravel the molecular mechanisms; however, basic and clinical studies of good validity are still not enough to translate experimental results into clinical understanding and to provide tough evidence for better use of herbal medicines. There are still issues regarding the conflicting pharmacologic effects, pharmacokinetics, drug interactions, adverse and clinical effects of herbal medicine and TCM. Understanding study validation, pharmacologic effects, drug interactions, indications and clinical effects, adverse effects and limitations, can all help clinicians in providing adequate suggestions to patients. At present, it would be better to use herbs and TCM formulas according to their traditional indications matching the disease pathophysiology and their molecular mechanisms. To unravel the molecular mechanisms and understand the benefits and harms of herbal medicine and TCM, there is still much work to be done.

The isoflavone puerarin induces Foxp3+ regulatory T cells by augmenting retinoic acid production, thereby inducing mucosal immune tolerance in a murine food allergy model

The disruption of intestinal mucosal immune tolerance can lead to the development of intestinal immune diseases such as food allergy (FA). Regulatory T cells (Tregs) in the mucosa play a critical role in maintaining peripheral immune tolerance in the intestine, and retinoic acid (RA) is absolutely required for the induction of Tregs. We have previously reported that kakkonto, a traditional Japanese herbal medicine, suppresses FA in a murine FA model due to the induction of Tregs in the colonic mucosa. However, the precise molecular mechanisms underlying the induction of Tregs remain unclear. Puerarin, an isoflavone derivative, is a major constituent of kakkonto. Thus, we investigated the effect of puerarin on the induction of Tregs. BALB/c mice were systemically sensitized and then orally challenged with ovalbumin (OVA) as an FA model. Puerarin treatment suppressed the development of allergic diarrhea in FA mice. The gene expression levels of IL-4 and mast cell protease I (mMCP-1) were significantly upregulated in the proximal colon of FA mice but were reduced by puerarin. The proportions of Foxp3⁺CD4⁺ cells and CD103⁺CD11c⁺ dendritic cells (DCs) were significantly higher among the colonic lamina propria (cLP) cells of puerarin-treated FA mice than among those of untreated FA mice. The gene expression of Aldh1a1, an RA synthesis enzyme, in colonic epithelial cells (CECs) was significantly higher in the puerarin-treated FA mouse colon than in the untreated FA mouse colon. In addition, the preventive effect of puerarin was suppressed in the FA model by pretreatment with LE540, an RA receptor (RAR) antagonist. The induction of Foxp3⁺CD4⁺ cells and CD103⁺CD11c⁺ DCs by puerarin was reduced by pretreatment with LE540. The present findings indicate that the augmentation of RA production in CECs induced by puerarin enhances the induction of Tregs and suppresses the development of FA in a mouse model. Thus, a natural enhancer of RA production, such as puerarin, has the potential to treat immune diseases attributed to Treg deficiency.

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

BACKGROUND

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

PURPOSE

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

METHODS

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

CHAPTERS

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

CONCLUSION

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

Puerarin alleviates delayed-type hypersensitivity via cytokine inhibition by modulating Th1/Th2 balance

Puerarin has long been used as a traditional Chinese medicine, which possesses various physiological properties, including anti-inflammation, anti-oxidative, anti-diabetic and anti-cancer activities. The aim of the current study was to investigate the effect of puerarin on delayed-type hypersensitivity (DTH) induced by ovalbumin (OVA) in mice and explore its underlying mechanisms. The results showed that puerarin significantly attenuated DTH, resulting from a decrement in footpad swelling, reduction in inflammatory cell as well as a decline in anti-OVA IgG in serum. In the homogenized supernatant of footpad tissues, the classic Th1-cytokines, including interferon (IFN)-γ was suppressed following puerarin treatment. Furthermore, a high dose of puerarin inhibited interleukin (IL)-4 production, the classic Th2-cytokine. The concanavalin A stimulation and MTT assays indicated a suppressive effect of puerarin on Th1 response via decreasing IFN-γ production in OVA-primed lymphocytes. Detailed studies revealed that puerarin modulated the Th1/Th2 balance in DTH responses, attributing to lower T-bet/GATA binding protein-3 mRNA and protein level ratios, which led to the shift change of IFN-γ/IL-4 with puerarin treatment. These findings demonstrate that puerarin alleviated inflammation in DTH triggered by OVA application via curbing inflammatory cytokines by modulating the Th1/Th2 balance. These results suggest that puerarin may be an alternative therapeutic option for the treatment of DTH.

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

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

PLAG (1-Palmitoyl-2-Linoleoyl-3-Acetyl-rac-Glycerol) Modulates Eosinophil Chemotaxis by Regulating CCL26 Expression from Epithelial Cells

Increased number of eosinophils in the circulation and sputum is associated with the severity of asthma. The respiratory epithelium produces chemokine (C-C motif) ligands (CCL) which recruits and activates eosinophils. A chemically synthesized monoacetyl-diglyceride, PLAG (1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol) is a major constituent in the antlers of Sika deer (Cervus nippon Temminck) which has been used in oriental medicine. This study was aimed to investigate the molecular mechanism of PLAG effect on the alleviation of asthma phenotypes. A549, a human alveolar basal epithelial cell, and HaCaT, a human keratinocyte, were activated by the treatment of interleukin-4 (IL-4), and the expression of chemokines, known to be effective on the induction of eosinophil migration was analyzed by RT-PCR. The expression of IL-4 induced genes was modulated by the co-treatment of PLAG. Especially, CCL26 expression from the stimulated epithelial cells was significantly blocked by PLAG, which was confirmed by ELISA. The transcriptional activity of signal transducer and activator of transcription 6 (STAT6), activated by IL-4 mediated phosphorylation and nuclear translocation, was down-regulated by PLAG in a concentration-dependent manner. In ovalbumin-induced mouse model, the infiltration of immune cells into the respiratory tract was decreased by PLAG administration. Cytological analysis of the isolated bronchoalveolar lavage fluid (BALF) cells proved the infiltration of eosinophils was significantly reduced by PLAG. In addition, PLAG inhibited the migration of murine bone marrow-derived eosinophils, and human eosinophil cell line, EoL-1, which was induced by the addition of A549 culture medium.

Puerarin attenuates smoke inhalation injury by regulation of Th1/Th2 expression and inhibition of Th17 cells in rats

OBJECTIVE

Puerarin, a kind of traditional Chinese medicine, possesses immunomodulatory property. However, the immunomodulatory effects of puerarin on smoke inhalation injury have not been determined. The aim of the current study was to investigate the therapeutic efficacy of puerarin on gunpowder smog-induced acute lung injury in rats via regulation of Th1/Th2/Th17 expression.

MATERIALS AND METHODS

Wistar rats were equally randomized to four groups (normal control group, puerarin control group, smoke inhalation injury group, puerarin treatment plus smoke inhalation injury group). The severity of lung injury was evaluated by histopathology, myeloperoxidase (MPO) activity in lung homogenates, cell counting in bronchoalveolar lavage fluid (BALF), and lung vascular permeability parameters including lung wet to dry weight ratio and protein concentration in BALF. Flow cytometry was used to analyze the expression of Th1/Th2/Th17 lymphocytes in blood of rats.

RESULTS

Puerarin showed significant therapeutic effects against neutrophil infiltration and tissue injury, as evidenced by histopathological findings and MPO activity. Lung vascular permeability was also relieved by puerarin administration. Additionally, puerarin significantly decreased the number of neutrophils and lymphocytes in BALF compared with smoke inhalation injury group. Furthermore, puerarin increased Th1 immunity and reduced Th2 and Th17 responses and thereby altering the Th1/Th2/Th17 imbalance induced by smoke inhalation.

CONCLUSIONS

Our findings suggested that puerarin suppressed inflammatory responses in gunpowder smog-induced acute lung injury by regulation of Th1/Th2/Th17 expression, and may be a potential therapeutic agent for smoke inhalation injury.

Cordycepin alleviates airway hyperreactivity in a murine model of asthma by attenuating the inflammatory process

Cordycepin (Cor), which is a naturally occurring nucleoside derivative isolated from Cordyceps militaris, has been shown to exert excellent antiinflammatory activity in a murine model of acute lung injury. Thus, this study aimed to evaluate the antiasthmatic activity of Cor (10, 20, and 40 mg/kg) and to investigate the possible underlying molecular mechanisms. We found that Cor attenuated airway hyperresponsiveness, mucus hypersecretion, and ovalbumin (Ova)-specific immunoglobulin (Ig) E, and alleviated lung inflammation with decreased eosinophils and macrophages in the bronchoalveolar lavage (BAL) fluid. Notably, Cor reduced the upregulation of eotaxin, intercellular cell adhesion molecule-1 (ICAM-1), IL-4, IL-5, and IL-13 in the BAL fluid. Furthermore, Cor markedly blocked p38-MAPK and nuclear factor-kappaB (NF-κB) signalling pathway activation in the Ova-driven asthmatic mice. In conclusion, this study demonstrated that some of the antiasthmatic benefits of Cor attributable to diets and/or tonics may result from reductions in inflammatory processes and that these antiasthmatic properties involve the inhibition of Th2-type responses through the suppression of the p38-MAPK and NF-κB signalling pathways.