Sulfur-dioxide derivatives aggravated Ovalbumin-induced asthma through targeting TRPV1 and tight junctions

This study aimed to investigate the effects of Sulfur dioxide (SO2) derivatives on asthma induced by ovalbumin (OVA). Sprague Dawley (SD) rats were sensitized to and challenged with OVA and SO2 derivatives (NaHSO3 and Na2SO3, 1:3 M/M) to establish 28-day (short-term) and 42-day (long-term) asthma models. Exposure to SO2 derivatives aggravated asthma and hence, promoted lung injury in OVA-induced asthma. In addition, it upregulated the protein expression of TRPV1 and downregulated the expression of TJs. These changes were dose-dependent and were more pronounced in the presence of a high concentration of SO2 derivatives. In vitro, SO2 derivatives also increased the calcium influx and TRPV1 protein expression, and decreased TJs expression. Besides, no significant difference in the TJs expression was found between the WT and TRPV1-/- mice. The underlying mechanism might be related regulating the effects of TRPV1 and TJs.

Development of an Orally Bioavailable Isoliquiritigenin Self-Nanoemulsifying Drug Delivery System to Effectively Treat Ovalbumin-Induced Asthma

Purpose

Isoliquiritigenin (ILQ), an important component of Anti-Asthma Herbal Medicine Intervention (ASHMI), had shown potent anti-asthma effect in vitro in our previous study. However, poor solubility and low bioavailability hindered in vivo application to treat asthma. This study was to develop a novel ILQ loaded self-nanoemulsifying drug delivery system (ILQ-SMEDDS) with enhanced bioavailability.

Methods

The optimized SMEDDS formulation was composed of ethyl oleate (oil phase), Tween 80 (surfactant) and PEG400 (co-surfactant) at a mass ratio of 3:6:1. The physiochemical properties of ILQ-SMEDDS, including drug content, globule size, zeta potential, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, were characterized. And the in vitro release profile, in situ intestinal absorption, in vivo pharmacokinetic parameters and the anti-asthma effect of ILQ suspension and ILQ-SMEDDS were evaluated.

Results

The ILQ-SMEDDS had an average globule size of 20.63 ± 1.95 nm with a polydispersity index (PDI) of 0.11 ± 0.03, and its zeta potential was −12.64 ± 2.12 mV. The cumulative release rate of ILQ from ILQ-SMEDDS to the simulated gastrointestinal tract was significantly higher than that of free ILQ suspension. And area under curve with ILQ-SMEDDS was found to be 3.95 times higher than that of ILQ suspension indicating improved bioavailability by SMEDDS. Although ILQ-SMEDDS showed a slight less effective inhibitory effect on eotaxin-1 in human lung fibroblast (HFL-1) cells than free ILQ, in an ovalbumin-induced asthma model, ILQ-SMEDDS exhibited more efficacy than ILQ suspension in improving asthma-associated inflammation, including eosinophil production, ovalbumin-specific immunoglobulin E (OVA-sIgE), interleukin 4 (IL 4), interleukin 5 (IL 5) and interferon-γ (IFN-γ). Even the low dose of ILQ-SMEDDS group (10 mg/kg) showed better anti-asthma effect than that of the ILQ suspension group (20 mg/kg).

Conclusion

Compared with ILQ suspension, ILQ-SMEDDS showed significantly improved bioavailability and anti-asthma effect, revealing its potential as a favorable pharmaceutical agent for treating asthma.

Interleukin-16 aggravates ovalbumin-induced allergic inflammation by enhancing Th2 and Th17 cytokine production in a mouse model

Asthma is a chronic inflammatory disease that involves a variety of cytokines and cells. Interleukin-16 (IL-16) is highly expressed during allergic airway inflammation and is involved in its development. However, its specific mechanism of action remains unclear. In the present study, we used an animal model of ovalbumin (OVA)-induced allergic asthma with mice harboring an IL-16 gene deletion to investigate the role of this cytokine in asthma, in addition to its underlying mechanism. Increased IL-16 expression was observed during OVA-induced asthma in C57BL/6J mice. However, when OVA was used to induce asthma in IL-16^-/- mice, a diminished inflammatory reaction, decreased bronchoalveolar lavage fluid (BALF) eosinophil numbers, and the suppression of OVA-specific IgE levels in the serum and BALF were observed. The results also demonstrated decreased levels of T helper type 2 (Th2) and Th17 cytokines upon OVA-induced asthma in IL-16^-/- mice. Hence, we confirmed that IL-16 enhances the lung allergic inflammatory response and suggest a mechanism possibly associated with the up-regulation of IgE and the promotion of Th2 and Th17 cytokine production. This work explored the mechanism underlying the regulation of IL-16 in asthma and provides a new target for the clinical treatment of asthma.

Nebivolol attenuates oxidative stress and inflammation in a guinea pig model of ovalbumin-induced asthma: a possible mechanism for its favorable respiratory effects

An experimental model of ovalbumin (OVA) induced asthma was used to assess the effects of nebivolol, the third-generation selective β₁-adrenergic receptor blocker, on airway reactivity, lung inflammation, and oxidative stress markers. The asthma induction protocol was done by OVA sensitization and challenge. Guinea pigs were classified into control, asthmatic, or asthmatic receiving nebivolol either 7.5 or 15 mg·kg^-1·day^-1 orally. At the end of the study respiratory, the anti-inflammatory and antioxidative effects of nebivolol were assessed. The asthmatic group exhibited a significant increase in early and late airway resistance, airway hyperreactivity to histamine, total and absolute leucocytic count, tumor necrosis factor-α, and interleukin-6 in bronchoalveolar lavage fluid and lung lipid peroxidation and a significant decrease in superoxide dismutase and glutathione compared to the control group. Additionally, there was a significant decrease in lung endothelial nitric oxide synthase (eNOS) and a significant increase in inducible nitric oxide synthase (iNOS) mRNA expression compared to the control group. The high dose of nebivolol counteracted the increased airway resistance induced by OVA, whereas it had no effect on airway hyperresponsiveness. Moreover, nebivolol exhibited significant anti-inflammatory and antioxidant effects and restored the altered levels of eNOS and iNOS compared to the asthmatic group. Collectively, these results suggest a beneficial effect of nebivolol in asthma.

Opuntia humifusa modulates morphological changes characteristic of asthma via IL-4 and IL-13 in an asthma murine model

Asthma is a chronic pulmonary disease that affects an estimated 235 million people worldwide, but asthma drugs have many adverse effects. Opuntia humifusa (eastern prickly pear) has been used as a food and traditional medicine worldwide; however, its anti-asthmatic effects have not been reported. We evaluated O. humifusa as a potential therapeutic or preventive component of anti-asthmatic drugs. We divided ovalbumin-sensitized mice into the following groups: normal control, asthma-induced control, dexamethasone-treated group (positive control), 50 mg/kg O. humifusa-treated group, 100 mg/kg O. humifusa-treated group, and 500 mg/kg O. humifusa-treated group. Levels of Th1/Th2/Th17-related cytokines were evaluated using RT-PCR, ELISA, and immunohistochemistry. O. humifusa dose-dependently suppressed the morphological changes typically observed in asthma, such as goblet cell hyperplasia, inflammatory cell infiltration, mucous hypersecretion, and relative basement membrane thickening in the respiratory system. These results may be attributable to regulation of Th1-/Th2-/Th17-related factors, especially interleukin (IL)-4 and IL-13. We conclude that O. humifusa is a potential anti-asthmatic functional food.

Abbreviations: O. humifusa: Opuntia humifusa; Th: helper T; RT-PCR: real-time polymerase chain reaction; ELISA: enzyme-linked immunosorbent assay; IL: interleukin; WHO: World Health Organization; IFN-γ: interferon gamma; TNF-α: tumor necrosis factor-alpha; IgE: immunoglobulin E; CD: cluster of differentiation; OVA: ovalbumin; DEX: dexamethasone; BALF: bronchoalveolar fluid; H&E: hematoxylin and eosin; PAS: periodic acid-schiff; PBS: phosphate-buffered saline; BM: basement membrane; cDNA: complementary deoxyribonucleic acid; RNA: ribo nucleic acid; RIPA: radioimmunoprecipitation assay; IHC: immunohistochemistry; HPLC: high-performance liquid chromatography; SD: standard deviation; WBC: white blood cells; APCs: antigen-presenting cells