RESUMEN
Purpose@#Asthma is a chronic airway inflammatory disorder and is associated with macrophages. Statin, a well-known lipid-lowering agent, has recently been noted for its anti-inflammatory effect on macrophage. This study was designed to evaluate the antiasthmatic effect of atorvastatin via modulation of macrophage activation by using an animal model of allergic asthma. @*Methods@#Atorvastatin 40 mg/kg was given by gavage once a day for 3 days before challenge of ovalbumin (OVA); airway hyperresponsiveness (AHR), airway inflammatory cells, and cytokines were evaluated in the murine asthma model. The direct effect of atorvastatin on the activation of macrophages In vitro was determined using the alveolar macrophage cell line CRL-2456. @*Results@#Administration of atorvastatin reduced the numbers of total inflammatory cells, macrophages, and eosinophils as well as lung histology enhanced in the murine asthma model. AHR measured by enhanced pause was significantly reduced after atorvastatin administration in the murine asthma model (P< 0.05). Atorvastatin administration resulted in the reduction in serum OVA-specific IgE levels and the increase in serum OVA-specific IgG2a levels (P< 0.05). The mRNA levels of Ccr3, Il-17, and Muc5ac enhanced by OVA challenge were decreased by treatment with atorvastatin (P< 0.05). Along with these improvement in allergic inflammatory changes, the population of CD11c-CD206+ macrophages as well as the expression of Ym-1 and Relm-α in the lungs were reduced with atorvastatin (P< 0.05). In vitro test with CRL-2456 showed that atorvastatin reduced the expression of Cd206, Arg-1, and Fgf-2 induced by IL-4 stimulation (P< 0.05). @*Conclusion@#This study highlighted the antiasthmatic effect of atorvastatin on the suppression of M2 macrophage activation in allergic asthma.
RESUMEN
Purpose@#Asthma is a common chronic lung disease, in which interleukin (IL)-13 is implicated as a central regulator of IgE synthesis, mucus hypersecretion, airway hyperresponsiveness (AHR), and fibrosis. This study was designed to determine the anti-inflammatory effect of atorvastatin, a widely used lipid-lowering agent, on the IL-13-induced lung pathology through the modulation of macrophages. @*Methods@#Atorvastatin (40 mg/kg) was given to transgenic mice overexpressing IL-13 (IL-13 TG mice) and their wild type littermates by oral gavage for 2 weeks. AHR, numbers of inflammatory cells in the airway, and cytokine levels in IL-13 TG mice were measured.Using the alveolar macrophage cell line CRL-2456, the direct effect of atorvastatin on macrophages activated by recombinant IL-13 was assessed. @*Results@#Significant reduction in total leukocytes and alleviation of AHR were observed with administration of atorvastatin in IL-13 TG mice compared to those without atorvastatin treatment (P< 0.05). Atorvastatin administration resulted in upregulation of IL-10 in the lungs of IL-13 TG mice (P< 0.05). In addition, mRNA expression of connective tissue growth factor, fibronectin, and type III collagen as well as chord length enhanced by IL-13 overexpression were reduced by atorvastatin administration (P< 0.05). M2 macrophage markers, such as Ym-1 and CD206, were decreased, while M1 macrophage marker, inducible nitric oxide synthase, was increased upon atorvastatin treatment (P< 0.05). Administration of atorvastatin resulted in improved removal of apoptotic cells (P< 0.05). @*Conclusion@#The results of this study reveal a potential of atorvastatin as an effective antiasthmatic agent by reducing IL-13-induced lung inflammation via the modulation of macrophage polarization.
RESUMEN
Asthma is a chronic inflammatory disease characterized by airway hyperresponsiveness (AHR) and reversible airway obstruction. Methacholine (MCh) is widely used in broncho-provocation test to evaluate airway resistance. For experimental investigation, ovalbumin-induced sensitization is frequently used in rodents (Ova-asthma). However, albeit the inflammatory histology and AHR in vivo, it remains unclear whether the MCh sensitivity of airway smooth muscle isolated from Ova-asthma is persistently changed. In this study, the contractions of airways in precision-cut lung slices (PCLS) from control, Ova-asthma, and IL-13 overexpressed transgenic mice (IL-13TG) were compared by analyzing the airway lumen space (AW). The airway resistance in vivo was measured using plethysmograph. AHR and increased inflammatory cells in BAL fluid were confirmed in Ova-asthma and IL-13TG mice. In the PCLS from all three groups, MCh concentration-dependent narrowing of airway lumen (DeltaAW) was observed. In contrast to the AHR in vivo, the EC50 of MCh for DeltaAW from Ova-asthma and IL-13TG were not different from control, indicating unchanged sensitivity to MCh. Although the AW recovery upon MCh-washout showed sluggish tendency in Ova-asthma, the change was also statistically insignificant. Membrane depolarization-induced DeltaAW by 60 mM K+ (60K-contraction) was larger in IL-13TG than control, whereas 60K-contraction of Ova-asthma was unaffected. Furthermore, serotonin-induced DeltaAW of Ova-asthma was smaller than control and IL-13TG. Taken together, the AHR in Ova-asthma and IL-13TG are not reflected in the contractility of isolated airways from PCLS. The AHR of the model animals seems to require intrinsic agonists or inflammatory microenvironment that is washable during tissue preparation.