Objective:To evaluatethe therapeutic efficacy and underlying mechanism of sodium houttuyfonate in treating airway inflammation in allergic asthma induced by co-exposure to the environmental pollutant benzo[a] pyrene (BaP) and ovalbumin (OVA).Methods:Thirty BALB/c mice were randomly divided into five groups with six mice in each group using a block randomization method: control, BaP, asthma model (OVA), BaP-exacerbated asthma (BaP+ OVA), and sodium houttuyfonate-treated BaP-exacerbated asthma (BaP+ OVA+ SH) groups. A mouse model of exacerbated asthma induced by co-exposure to BaP and OVA was established. Airway hyperresponsiveness, leukocyte distribution in bronchoalveolar lavage fluid (BALF), expression of cytokines such as IL-4, IL-13, IL-25, IL-33, thymic stromal lymphopoietin (TSLP) and IFN-γ, serum OVA-specific antibodies (IgE, IgG2a and IgG1), levels of malondialdehyde and superoxide dismutase (SOD) in lung tissues, and histopathological changes in lung tissues were evaluated. Western blot and RT-qPCR were used to detect the protein and mRNA expression levels of suppression of tumorigenicity 2 (ST2), extracellular regulated protein kinases (ERK), and phosphorylated ERK (p-ERK). Statistical analysis was conducted using analysis of variance and other statistical methods.Results:Compared with the BaP+ OVA group, the mice in the BaP+ OVA+ SH group showed significantly reduced airway hyperresponsiveness ( P<0.01), decreased numbers of total leukocytes ( P<0.01), neutrophils ( P<0.05), and lymphocytes ( P<0.01) in BALF, significantly downregulated secretion of IL-4, IL-13, IL-25, IL-33 and TSLP ( P<0.01), and inhibited production of IgE ( P<0.01) and IgG1 ( P<0.05). Additionally, sodium houttuyfonate treatment significantly decreased the malondialdehyde levels in lung tissues of mice with BaP-exacerbated asthma ( P<0.05) and reduced airway inflammatory cell infiltration, mucus secretion, and collagen fiber proliferation. Sodium houttuyfonate could supress the expression of ST2 and ERK ( P<0.05), inhibit ERK phosphorylation ( P<0.01), alleviate oxidative stress injury, and reduce collagen fiber proliferation in mouse lung tissues, thereby blocking the progression of BaP-exacerbated asthmatic inflammation. Conclusions:BaP exacerbates OVA-sensitized asthmatic airway inflammation in mice by inducing airway remodeling through the IL-33-ST2/ERK pathway. Sodium houttuyfonate inhibits this pathway, thereby preventing the progression of BaP-exacerbated asthma inflammation. This study provides new insights into the prevention and treatment of different phenotypes of asthma.

Objective:To evaluatethe therapeutic efficacy and underlying mechanism of sodium houttuyfonate in treating airway inflammation in allergic asthma induced by co-exposure to the environmental pollutant benzo[a] pyrene (BaP) and ovalbumin (OVA).Methods:Thirty BALB/c mice were randomly divided into five groups with six mice in each group using a block randomization method: control, BaP, asthma model (OVA), BaP-exacerbated asthma (BaP+ OVA), and sodium houttuyfonate-treated BaP-exacerbated asthma (BaP+ OVA+ SH) groups. A mouse model of exacerbated asthma induced by co-exposure to BaP and OVA was established. Airway hyperresponsiveness, leukocyte distribution in bronchoalveolar lavage fluid (BALF), expression of cytokines such as IL-4, IL-13, IL-25, IL-33, thymic stromal lymphopoietin (TSLP) and IFN-γ, serum OVA-specific antibodies (IgE, IgG2a and IgG1), levels of malondialdehyde and superoxide dismutase (SOD) in lung tissues, and histopathological changes in lung tissues were evaluated. Western blot and RT-qPCR were used to detect the protein and mRNA expression levels of suppression of tumorigenicity 2 (ST2), extracellular regulated protein kinases (ERK), and phosphorylated ERK (p-ERK). Statistical analysis was conducted using analysis of variance and other statistical methods.Results:Compared with the BaP+ OVA group, the mice in the BaP+ OVA+ SH group showed significantly reduced airway hyperresponsiveness ( P<0.01), decreased numbers of total leukocytes ( P<0.01), neutrophils ( P<0.05), and lymphocytes ( P<0.01) in BALF, significantly downregulated secretion of IL-4, IL-13, IL-25, IL-33 and TSLP ( P<0.01), and inhibited production of IgE ( P<0.01) and IgG1 ( P<0.05). Additionally, sodium houttuyfonate treatment significantly decreased the malondialdehyde levels in lung tissues of mice with BaP-exacerbated asthma ( P<0.05) and reduced airway inflammatory cell infiltration, mucus secretion, and collagen fiber proliferation. Sodium houttuyfonate could supress the expression of ST2 and ERK ( P<0.05), inhibit ERK phosphorylation ( P<0.01), alleviate oxidative stress injury, and reduce collagen fiber proliferation in mouse lung tissues, thereby blocking the progression of BaP-exacerbated asthmatic inflammation. Conclusions:BaP exacerbates OVA-sensitized asthmatic airway inflammation in mice by inducing airway remodeling through the IL-33-ST2/ERK pathway. Sodium houttuyfonate inhibits this pathway, thereby preventing the progression of BaP-exacerbated asthma inflammation. This study provides new insights into the prevention and treatment of different phenotypes of asthma.

Objective: To synthesize a folic acid (FA)-modified pH-sensitive nanomicelle containing sorafenib (SF) and superparamagnetic iron oxide (SPIO), and to access its visibility in MRI and anti-cancer efficacy on hepatocellular carcinoma (HCC) in vitro. Methods: The copolymer FA-PEG-Pasp (DBA/DIP) of FA, poly(ethylene glycol), N,N-dibutylethylenediamine and N,N-diisopropylethylenediamine grafted poly (L-aspartic acid) were prepared. SF and SPIO were encapsulated inside the copolymer to synthesize the targeting micelle FA-PEG-PAsp (DBA/DIP)-SPIO/SF (FPASS). The folate-free micelle[PEG-PAsp (DBA/DIP)-SPIO/SF (PASS)] was used as nontargeting micelle. The physicochemical properties and drug release behavior of the micelles were analyzed. MRI of HepG2 cells incubated with FPASS and PASS with different Fe concentrations and Prussian blue staining of cells treated with the micelles (Fe concentration of 20 μg/ml) was performed to assess the drug delivery capability and imaging function of the micelles. For the FA competitive inhibition assay in these experiments, HepG2 cells were pre-treated with an excess amount of free FA prior to the incubation with FPASS. Cell viability, cell apoptosis, cell cycle and tube formation assays were conducted for evaluating the anti-HCC effects of the micelles. Comparison between groups was analyzed by one-way ANOVA, and multiple comparisons correction was performed by LSD test. Results: The diameters of FPASS and PASS were (102.3±5.2) nm and (107.1±5.7) nm, respectively; the δ potentials of them were (29.7±1.6) mV and (31.5±1.4) mV, respectively. The T₂ relaxivity of both the micelles was (5.2±0.4) ml·μg^-1·s^-1, which was much higher than that of water soluble Fe₃O₄ nanoparticles [(2.3±0.1) ml·μg^-1·s^-1; F=76.45, P<0.01]. SF released from the micelles was much faster at pH5.0 than at pH7.4, which indicated that the micelles had a pH-triggered drug release behavior. MRI of HepG2 cell samples revealed the signal intensity on T₂WI images and the T₂ value on T₂-map images decreased with the increasing Fe concentrations in the micelles. At the same Fe concentration (5, 10, 20 and 40 μg/ml), the cells of FPASS group exhibited a more significant decrease in T₂ signal intensity and T₂ value compared with those of PASS group or FA competitive inhibition group (F=8.69, 14.03, 27.27, 32.25 and 19.80, 45.76, 113.20, 66.80; P<0.01). Prussian blue staining verified the existing of SPIO in the cytoplasm of cells. Compared with PASS, FPASS presented significantly higher anticancer effects on inducing apoptosis, causing G0/G1 phase arrest on HepG2 cells and inhibiting tube formation on human umbilical vein endothelial cells (t=7.905, 4.399 and 3.454, respectively; P<0.01). Conclusions The pH-sensitive nanomicelle FPASS was successfully constructed. This micelle possessed a hypersensitive MRI-visible function and a targeting SF delivery capability which may contribute to a significant anti-HCC effect.