Combined treatment with SB203580 and dexamethasone suppresses non-typeable Haemophilus influenzae-induced Th17 inflammation response in murine allergic asthma.

Accumulating evidence suggests that non-typeable Haemophilus influenzae (NTHi) infection drives the development of steroid-resistant allergic airway disease (SRAAD), exacerbates clinical symptoms, worsens quality of life, and accounts for most of the related healthcare burden. The poor understanding of the pathogenesis of SRAAD deters the development of more effective therapeutic strategies. Here, we established a murine model of NTHi infection-induced exacerbation of allergic airway disease. We showed that NTHi infection drove Th 17-mediated pulmonary neutrophilic inflammation, aggravated airway hyper-responsiveness, and upset the balance of MUC5AC and MUC5B expression. Dexamethasone treatment effectively inhibited the features of allergic airway disease but failed to reduce NTHi-induced exacerbation, which was associated with the hyper-phosphorylation of p38 mitogen-activated protein kinase (MAPK). Interestingly, inhibition of p38 using a specific inhibitor (SB203580) only partly suppressed the airway hyper-responsiveness and mucus hyper-secretion but failed to abrogate the infection-induced neutrophilic inflammatory response in SRAAD. However, SB203580 and dexamethasone co-treatment substantially suppressed all the features of NTHi-induced SRAAD. Our findings highlight the importance of p38 MAPK in the pathogenesis of NTHi-induced steroid resistance, and this combined treatment approach may be a novel strategy against steroid-resistant asthma.

An Updated Overview of Metabolomic Profile Changes in Chronic Obstructive Pulmonary Disease.

Chronic obstructive pulmonary disease (COPD), a common and heterogeneous respiratory disease, is characterized by persistent and incompletely reversible airflow limitation. Metabolomics is applied to analyze the difference of metabolic profile based on the low-molecular-weight metabolites (<1 kDa). Emerging metabolomic analysis may provide insights into the pathogenesis and diagnosis of COPD. This review aims to summarize the alteration of metabolites in blood/serum/plasma, urine, exhaled breath condensate, lung tissue samples, etc. from COPD individuals, thereby uncovering the potential pathogenesis of COPD according to the perturbed metabolic pathways. Metabolomic researches have indicated that the dysfunctions of amino acid metabolism, lipid metabolism, energy production pathways, and the imbalance of oxidations and antioxidations might lead to local and systematic inflammation by activating the Nuclear factor kappa-light-chain-enhancer of activated B cells signaling pathway and releasing inflammatory cytokines, like interleutin-6 (IL-6), tumor necrosis factor-α, and IL-8. In addition, they might cause protein malnutrition and oxidative stress and contribute to the development and exacerbation of COPD.

Protective effect of amygdalin on epithelial-mesenchymal transformation in experimental chronic obstructive pulmonary disease mice.

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory pulmonary disease characterized by continuous, progressive limitation of airflow. Airway remodelling, which is correlated with epithelial-mesenchymal transitions (EMTs), is a typical pathophysiological change of COPD. Amygdalin, an active ingredient in the traditional Chinese medicine bitter almond with extensive pharmacological effects, was shown to inhibit tissue fibrosis in recent studies. In this study, a human bronchial epithelial cell line (BEAS-2B) and mice were exposed to cigarette smoke, and EMT levels were investigated after treatment with different concentrations of amygdalin. Morphology was assessed by immunohistochemical staining. Evaluation of the expression of TGF-ß1, smad2/3, and p-smad2/3 in lung tissue was conducted out via ELISA, Western blot, and real-time PCR. The results showed that E-cadherin expression was significantly increased, whereas vimentin, TGF-ß1, and phosphorylated smad2/3 (p-smad2/3) expression was markedly decreased in the amygdalin-treated groups compared with the model group. Therefore, our study demonstrated a protective role of amygdalin in the murine EMT process after COPD.

Obesity-Related Asthma: Immune Regulation and Potential Targeted Therapies.

Obesity, one of the most severe public health problems of the 21st century, is a common metabolic syndrome due to excess body fat. The incidence and severity of obesity-related asthma have undergone a dramatic increase. Because obesity-related asthma is poorly controlled using conventional therapies, alternative and complementary therapies are urgently needed. Lipid metabolism may be abnormal in obesity-related asthma, and immune modulation therapies need to be investigated. Herein, we describe the immune regulators of lipid metabolism in obesity as well as the interplay of obesity and asthma. These lay the foundations for targeted therapies in terms of direct and indirect immune regulators of lipid metabolism, which ultimately help provide effective control of obesity-related asthma with a feasible treatment strategy.

The Role of Regulatory T Cell in Nontypeable Haemophilus influenzae-Induced Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

Chronic obstructive pulmonary disease (COPD) is associated with irreversible persistent airflow limitation and enhanced inflammation. The episodes of acute exacerbation (AECOPD) largely depend on the colonized pathogens such as nontypeable Haemophilus influenzae (NTHi), one of the most commonly isolated bacteria. Regulatory T cells (Tregs) are critical in controlling inflammatory immune responses and maintaining tolerance; however, their role in AECOPD is poorly understood. In this study, we hypothesized a regulatory role of Tregs, as NTHi participated in the progress of COPD. Immunological pathogenesis was investigated in a murine COPD model induced by cigarette smoke (CS). NTHi was administrated through intratracheal instillation for an acute exacerbation. Weight loss and lung function decline were observed in smoke-exposed mice. Mice in experimental groups exhibited serious inflammatory responses via histological and cytokine assessment. Expression levels of Tregs and Th17 cells with specific cytokines TGF-ß1 and IL-17 were detected to assess the balance of pro-/anti-inflammatory influence partially. Our findings suggested an anti-inflammatory activity of Tregs in CS-induced model. But this activity was suppressed after NTHi administration. Collectively, these data suggested that NTHi might play a necessary role in downregulating Foxp3 to impair the function of Tregs, helping development into AECOPD.