Lobeglitazone Attenuates Airway Inflammation and Mucus Hypersecretion in a Murine Model of Ovalbumin-Induced Asthma

Protective effects of Angelica decursiva Franchet & Savatier on allergic responses through enhancement of Nrf2 and suppression of NF-kB/MMP-9 in ovalbumin-exposed mice

ETHNOPHARMACOLOGICAL RELEVANCE

Angelica decursiva Franchet & Savatier is a traditional medicinal plant used to treat asthma, cough, headache, pyrexia and thick phlegm in China, Japan and Korea. A. decursiva contains many types of coumarins, which can exert several pharmacological activities including anti-inflammatory and antioxidant properties for treating various diseases such as pneumonitis, atopic dermatitis, diabetes, and Alzheimer's disease.

AIM OF THE STUDY

In this study, we analyzed the components of A. decursiva ethanol extract (ADE) by high performance liquid chromatography (HPLC) and investigated the therapeutic effects of ADE against allergic asthma using lipopolysaccharide (LPS) stimulated RAW264.7 cells and an ovalbumin (OVA)-exposed allergic asthma model. To elucidate the mechanism of action of ADE, we examined the protein expression through network pharmacological analysis.

MATERIALS AND METHODS

To establish asthma model, the mice were sensitized on day 0 and 14 via intraperitoneal injection of OVA with aluminum hydroxide. The mice were inhaled with OVA using an ultrasonic nebulizer on day 21, 22 and 23. ADE (50 and 100 mg/kg) was administered to mice by oral gave form day 18-23. On day 24, airway hyperresponsiveness (AHR) was measured using flexivent. On day 25, the mice were sacrificed and collected bronchoalveolar lavage fluids (BALF), serum and lung tissue. In LPS-stimulated RAW264.7 cell, nitric oxide and cytokines were measured. Additionally, expression of nuclear factor erythroid-2-related factor (Nrf2) and suppression of nuclear factor (NF)-κB were detected using double-immunofluorescence.

RESULTS

We detected the five coumarin components which included nodakenin, umbelliferon, (-)-marmesin (=nodakenetin), bergapten, and decursin, in ADE by high performance liquid chromatography. Treatment with ADE decreased the production of nitric oxide, interleukin (IL)-6 and tumor necrosis factor (TNF)-α in LPS-stimulated RAW264.7 cells accompanied by the enhanced expression of nuclear factor erythroid-2-related factor (Nrf2) and suppression of nuclear factor (NF)-κB. In the asthma model, the administration of ADE reduced inflammatory cell count and airway hyperresponsiveness in OVA-exposed animals with decreased levels of IL-4, IL-13, and OVA-specific immunoglobulin E. These results were accompanied by the reduction of pulmonary inflammation and mucus secretion. Furthermore, ADE administration inhibited the expression of NF-κB and matrix metalloproteinase (MMP)-9 in OVA-exposed animals, which was consistent with the results of network pharmacological analysis.

CONCLUSION

This study demonstrated that ADE effectively attenuated allergic inflammation induced by OVA inhalation through the enhancement of Nrf2 expression and suppression of NF-κB expression. Therefore, ADE may be a potential therapeutic agent for controlling asthma.

Gleditsia sinensis Lam. aqueous extract attenuates nasal inflammation in allergic rhinitis by inhibiting MUC5AC production through suppression of the STAT3/STAT6 pathway

Allergic rhinitis (AR), a chronic respiratory inflammatory disease, is among the most common chronic diseases reported worldwide. Mucus hypersecretion is a critical feature of AR pathogenesis. Although the Gleditsia sinensis extract has several beneficial effects on human health, its effects on allergic inflammation have not yet been investigated. In this study, we examined the effects of G. sinensis aqueous extract (GSAE) on nasal inflammation in an ovalbumin (OVA)-induced AR mouse model. GSAE was administered orally for 1 week and then the clinical nasal symptoms were evaluated. The levels of histamine, OVA-specific immunoglobulin (Ig) E, and interleukin (IL)-13 were measured in the serum using an enzyme-linked immunosorbent assay (ELISA). Inflammatory cells were then counted in the nasal lavage fluid (NALF) and histopathology in the nasal epithelium was evaluated. STAT3/STAT6 phosphorylation was examined in primary human nasal epithelial cells (HNEpCs) using western blot analysis. Oral administration of GSAE to OVA-induced AR mice alleviated nasal clinical symptoms and reduced OVA-specific immunoglobulin E, interleukin (IL)-13, and histamine levels. The accumulation of eosinophils in nasal lavage fluid, nasal mucosa, mast cells, goblet cells, and mucin 5AC (MUC5AC) in the nasal epithelium was also inhibited by GSAE. Treatment with GSAE inhibited the production of MUC5AC in IL-4/IL-13-stimulated primary human nasal epithelial cells through the signal transducer and activator of transcription (STAT)3/STAT6 signaling pathway. These results indicated that GSAE reduces nasal inflammation suggesting that it is a potential treatment option for AR.

Type 2 Diabetes Mellitus and Asthma: Pathomechanisms of Their Association and Clinical Implications

Type 2 diabetes mellitus (T2DM) and asthma are chronic illnesses concomitantly present in a significant percentage of the population. Their comorbidity is associated with poor disease control and lower quality of life, thus imposing a substantial medical and economic burden worldwide. This review investigates the association between asthma and T2DM, in terms of pathogenesis, clinical outcomes, and therapeutic opportunities. Our review found an increased risk of asthma among diabetics, and vice versa. Having diabetes and poor glycemic control is associated with an increased rate of asthma exacerbations and increased mortality among those hospitalized for asthma exacerbations. The mechanisms postulated for the diabetes-asthma association include chronic low-grade inflammation, obesity, hyperinsulinemia, and possibly diabetic pneumopathy. Usage of metformin, which is the first-line drug for type 2 diabetes, was found to be associated with a decreased asthma occurrence, asthma exacerbations, and asthma-related hospitalizations. Glucagon-like peptide 1 receptor agonists were also found to be associated with a lower occurrence of asthma exacerbations. Thiazolidinediones are also associated with lower rates of asthma exacerbations, but their clinical efficacy for the same was suggested to be limited. This literature review supports a partly causative association between asthma and diabetes. This comorbidity leads to poor patient compliance, worse disease outcomes, and poor quality of life. Thus, further studies are warranted to explore the prognostic implications, therapeutic opportunities, and specific clinical practice algorithms for patients with concurrent asthma and type 2 diabetes mellitus.

Anti-asthmatic effects of Phlomis umbrosa Turczaninow using ovalbumin induced asthma murine model and network pharmacology analysis

BACKGROUND

Phlomis umbrosa Turczaninow has been used as a tradition herbal medicine for treating various inflammatory diseases.

PURPOSE

In present study, we explored the effects of P. umbrosa on asthma induced by ovalbumin (OVA) and elucidated the mechanism via in vivo verification and network pharmacology prediction.

METHODS

The animals were intraperitoneally injected OVA on day 1 and 14, followed by OVA inhalation on days 21, 22, and 23. The animals were daily treated P. umbrosa extract (PUE, 20 and 40 mg/kg) by oral gavage from day 18 to day 23.

RESULTS

PUE significantly decreased airway hyperresponsiveness, eosinophilia, and the production of inflammatory cytokines and OVA specific immunoglobulin E in animals with asthma, along with a reduction in airway inflammation and mucus secretion in lung tissue. In network analysis, antiasthmatic effects of PUE were closely related with suppression of mitogen-activated protein kinases and matrix metalloproteinases (MMPs). Consistent with the results from network analysis, PUE suppressed the phosphorylation of ERK and p65, which was accompanied by a decline in MMP-9 expression.

CONCLUSION

Administration of PUE effectively reduced allergic responses in asthmatic mice, which was associated with the suppressed phosphorylation of ERK and p65, and expression of MMP-9. These results indicate that PUE has therapeutic potential to treat allergic asthma.

Adiponectin and Asthma: Knowns, Unknowns and Controversies

Adiponectin is an adipokine associated with the healthy obese phenotype. Adiponectin increases insulin sensitivity and has cardio and vascular protection actions. Studies related to adiponectin, a modulator of the innate and acquired immunity response, have suggested a role of this molecule in asthma. Studies based on various asthma animal models and on the key cells involved in the allergic response have provided important insights about this relation. Some of them indicated protection and others reversed the balance towards negative effects. Many of them described the cellular pathways activated by adiponectin, which are potentially beneficial for asthma prevention or for reduction in the risk of exacerbations. However, conclusive proofs about their efficiency still need to be provided. In this article, we will, briefly, present the general actions of adiponectin and the epidemiological studies supporting the relation with asthma. The main focus of the current review is on the mechanisms of adiponectin and the impact on the pathobiology of asthma. From this perspective, we will provide arguments for and against the positive influence of this molecule in asthma, also indicating the controversies and sketching out the potential directions of research to complete the picture.

Mechanisms Mediating the Regulation of Peroxisomal Fatty Acid Beta-Oxidation by PPARα

In mammalian cells, two cellular organelles, mitochondria and peroxisomes, share the ability to degrade fatty acid chains. Although each organelle harbors its own fatty acid β-oxidation pathway, a distinct mitochondrial system feeds the oxidative phosphorylation pathway for ATP synthesis. At the same time, the peroxisomal β-oxidation pathway participates in cellular thermogenesis. A scientific milestone in 1965 helped discover the hepatomegaly effect in rat liver by clofibrate, subsequently identified as a peroxisome proliferator in rodents and an activator of the peroxisomal fatty acid β-oxidation pathway. These peroxisome proliferators were later identified as activating ligands of Peroxisome Proliferator-Activated Receptor α (PPARα), cloned in 1990. The ligand-activated heterodimer PPARα/RXRα recognizes a DNA sequence, called PPRE (Peroxisome Proliferator Response Element), corresponding to two half-consensus hexanucleotide motifs, AGGTCA, separated by one nucleotide. Accordingly, the assembled complex containing PPRE/PPARα/RXRα/ligands/Coregulators controls the expression of the genes involved in liver peroxisomal fatty acid β-oxidation. This review mobilizes a considerable number of findings that discuss miscellaneous axes, covering the detailed expression pattern of PPARα in species and tissues, the lessons from several PPARα KO mouse models and the modulation of PPARα function by dietary micronutrients.

Trigonelline, An Alkaloid From Leonurus japonicus Houtt., Suppresses Mast Cell Activation and OVA-Induced Allergic Asthma

Trigonelline, one of the active compounds from Leonurus japonicus Houtt., has been proven to have pharmacological value in diabetes, the central nervous system and cardiovascular diseases. Recent studies have shown that it may also be beneficial in controlling inflammation. However, the mechanism of the antiallergic effects of trigonelline has not been well studied. As the key effector cells participating in the development of allergies, mast cells have been linked to the pathogenesis of asthma for ages. In this study, we demonstrated the inhibitory effect of trigonelline on activated bone marrow-derived mast cells (BMMCs) and verified its anti-inflammatory properties using an ovalbumin (OVA)-induced asthma model. Trigonelline suppressed BMMC degranulation and decreased the production of the cytokines, prostaglandin D2 (PGD2) and leukotriene C4 (LTC4) in a dose-dependent manner. The potent mechanism is mainly through the suppression of the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Trigonelline can alleviate pathological damage in lung tissue and reduce the levels of serum immunoglobulin E (IgE) and T helper 2 (Th2) cytokines. RNA-seq results revealed the HIF-1α to be a potential target for the allergic reaction. Taken together, our study demonstrated that trigonelline can inhibit allergic inflammation in vitro and in vivo, which may provide a basis for novel anti-inflammatory drug development.

Effect of Yijin-Tang, an Oriental Traditional Formula, on Allergic Responses Using an Ovalbumin-Induced Murine Asthma Model

Yijin-tang is an oriental traditional herb used to treat inflammatory diseases. In the present study, we investigated the protective effects of Yijin-tang water extract (YTE) using an ovalbumin- (OVA-) induced asthma model, focusing on the antioxidant and anti-inflammatory properties of the herb. BALB/c mice were intraperitoneally injected with OVA on days 0 and 14 and then challenged with OVA on days 21, 22, and 23. The animals were orally administered YTE (200 and 400 mg/kg) from days 18 to 23, and this was found to significantly decrease airway hyperresponsiveness and release of inflammatory cells, cytokines, and OVA-specific immunoglobulin E in mice with asthma. In addition, YTE was associated with a marked reduction in airway inflammation and mucus production in lung tissue of mice with asthma. Furthermore, YTE suppressed the expression of matrix metalloproteinase-9 and phosphorylation of ERK in the lungs, which in turn led to a reduction in inducible nitric oxide synthases and an elevation in reduced glutathione and heme oxygenase-1. In conclusion, YTE effectively suppressed allergic responses in mice with asthma and the effect was closely related to antioxidant and anti-inflammatory properties of the herb. Our results indicate that YTE may be a potential agent for the treatment of allergic asthma.

Lobeglitazone: A Novel Thiazolidinedione for the Management of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance and β-cell dysfunction. Among available oral antidiabetic agents, only the thiazolidinediones (TZDs) primarily target insulin resistance. TZDs improve insulin sensitivity by activating peroxisome proliferator-activated receptor γ. Rosiglitazone and pioglitazone have been used widely for T2DM treatment due to their potent glycemic efficacy and low risk of hypoglycemia. However, their use has decreased because of side effects and safety issues, such as cardiovascular concerns and bladder cancer. Lobeglitazone (Chong Kun Dang Pharmaceutical Corporation), a novel TZD, was developed to meet the demands for an effective and safe TZD. Lobeglitazone shows similar glycemic efficacy to pioglitazone, with a lower effective dose, and favorable safety results. It also showed pleiotropic effects in preclinical and clinical studies. In this article, we summarize the pharmacologic, pharmacokinetic, and clinical characteristics of lobeglitazone.

Synthesis and biological evaluation of Ginsenoside Compound K analogues as a novel class of anti-asthmatic agents

Ginsenoside Compound K (CK) showed potent activity against IgE for the treatment of asthma. A series of CK analogues were then synthesized by straightforward procedures. The in vivo anti-IgE activity evaluations using the OVA-induced asthmatic mouse model revealed preliminary SARs of the CK analogues, which showed that the sugar type, modifications on A-ring and the C20 side chain of CK all affected much on the activities. Primary SARs optimization led to the discovery of compounds T1, T2, T3, T8 and T12, which displayed superior or comparable anti-asthmatic effects (IgE value = 1237.11 ± 106.28, 975.82 ± 160.32, 1136.96 ± 121.85, 1191.08 ± 107.59 and 1258.27 ± 148.70 ng/mL, respectively) in comparison with CK (1501.85 ± 184.66 ng/mL). These potent compounds could serve as leads for further development.