2-Deoxy-D-glucose Ameliorates Murine Allergic Airway Inflammation Via Inhibiting Hif-1α-Mediated Glycolysis

BackgroundAs a common chronic respiratory disease,bronchial asthma is characterized by persistent chronic inflammation in the airway.It is often life-threatening due to airflow limitation during acute exacerbation,which brings a significant medical burden to patients and society.Asthma is a heterogeneous disease with multiple phenotypes.Allergic asthma is the most common type,which has a large number of inflammatory cell infiltration in the airway,and most of them are eosinophils.Allergic asthma is associated with eczema,allergic rhinitis,and food or drug allergic disorders.Inhaled glucocorticoids are the first choice for the treatment of allergic asthma.However,the use of glucocorticoids is often limited by the different sensitivity of individuals to glucocorticoids and many adverse reactions.With the rise of metabolomics,studies have found that metabolic reprogramming is significantly related to inflammation,and targeting glycolysis may have anti-inflammatory effects.Previous studies have shown that glycolysis inhibitor 2-Deoxy-D-glucose(2-DG)can reduce acute lung injury and inhibit inflammatory response in mice.However,whether 2-DG plays an anti-inflammatory role in asthma and airway inflammatory diseases,and how it works still need more experimental data to support.ObjectiveIn this study,Ovalbumin(OVA)was used as an allergen for sensitization and challenge to establish the murine model of allergic airway inflammation,and to explore whether 2-DG can play a therapeutic role in allergic airway inflammation and its possible mechanism.MethodsFemale,5-week-old,SPF grade C57BL/6J mice were used as experimental subjects.They were randomly divided into Vehicle group,OVA group and OVA+2-DG group(at a dose of 0.02 g per mouse).The total number of cells in Bronchoalveolar lavage fluid was calculated using a blood cell counting plate.Wright-Giemsa staining was used to distinguish different types of cells in lavage fluid.Hematoxylin-Eosin staining was used to evaluate the infiltration of inflammatory cells around the airway.The severity of airway mucus secretion and goblet cell proliferation was evaluated by Periodic Acid-Schiff staining.Western blot was used to observe the expression of IL-4,IL-5,IL-13,GSDMD,Caspase-1,IL-1β,HIF-1α,Glut1,HK1,HK2,HK3,PFK-1,PKM1,PKM2,LDH,PDK1,PDK4,CS,SDHA,FH,CD206,Arg1,Fizz1,iNOS and CD86 in lung tissue of mice.The expressions of HIF-1α,F4/80,CD206 and iNOS in lung tissue were detected by immunohistochemistry.The expression of CD206 and iNOS in lung tissue of mice was detected by immunofluorescence staining.Lactic acid and OVA-specific IgE(OVA-sIgE)levels were measured by enzyme-linked immunosorbent assay kits.ResultsIn the established allergic airway inflammation model,a large number of inflammatory cells(mainly eosinophil infiltration)were observed in and around the airway,accompanied by pathological manifestations such as alveolar morphology damage and increased secretion of mucus by goblet cells.The levels of Th2-type cytokines(IL-4,IL-5,IL-13),OVA-sIgE and lactic acid were increased in mice.After treatment with glycolysis inhibitor 2-DG,the above pathological changes and Th2 type immune response were alleviated,and the level of lactic acid was also significantly decreased.Meanwhile,Western Blot results showed that OVA stimulation promoted pyroptosis,glycolysis and subsequent glucose oxidation via HIF-1α,drived macrophage polarization,resulting in increased expression of the following proteins in lung tissues:GSDMD,Caspase-1 and IL-1β related to pyroptosis;HIF-1α,GLUT1,HK2,HK3,PFK-1,PKM2,LDH,PDK1,SDHA,FH related to glycolysis and glucose oxidation;CD206,Arg1,Fizz1,iNOS,and CD86 associated with macrophage polarization.In addition,the results of immunohistochemistry and immunofluorescence staining also confirmed the presence of high expression of HIF-1α and macrophage polarization in lung tissue.Most interestingly,the expression of these proteins was inhibited to varying degrees following application of 2-DG.ConclusionThese results suggest that glycolysis inhibitor 2-DG can significantly reduce the inflammatory response in the OVA-induced allergic airway inflammation murine model,and its mechanism may be related to the inhibition of HIF-1α-mediated glycolysis and macrophage polarization,which provides more theoretical basis for targeting glycolysis in the treatment of asthma.